[PATCH v7 0/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 support

[PATCH v7 0/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 support

[Niklas Söderlund]

From: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>

Hi,

This is the latest incarnation of R-Car MIPI CSI-2 receiver driver. It's
based on top of v4.12-rc1 and are tested on Renesas Salvator-X together
with the out of tree patches for rcar-vin to add support for Gen3 VIN
and a prototype driver for ADV7482. If anyone is interested to test
video grabbing using these out of tree patches please see [1].

It depends on the patches:

- [GIT PULL FOR v4.13] V4L2 fwnode support
- [PATCH v2 0/2] v4l2-async: add subnotifier registration for subdevices
- [PATCH v2 0/2] media: entity: add operation to help map DT node to media pad

Changes since v6:
- Rebased on top of Sakaris fwnode patches.
- Changed of RCAR_CSI2_PAD_MAX to NR_OF_RCAR_CSI2_PAD.
- Remove assumtion about unkown medis bus type, thanks Sakari for 
  pointing this out.
- Created table for supported format information instead of scattering 
  this information around the driver, thanks Sakari!
- Small newline fixes and reduce some indentation levels.

Changes since v5:
- Make use of the incremental async subnotifer and helper to map DT 
  endpoint to media pad number. This moves functionality which
  previously in the Gen3 patches for R-Car VIN driver to this R-Car
  CSI-2 driver. This is done in preparation to support the ADV7482
  driver in development by Kieran which will register more then one
  subdevice and the CSI-2 driver needs to cope wit this. Further more it
  prepares the driver for another use-case where more then one subdevice
  is present upstream for the CSI-2.
- Small cleanups.
- Add explicit include for linux/io.h, thanks Kieran.

Changes since v4:
- Match SoC part numbers and drop trailing space in documentation, 
  thanks Geert for pointing this out.
- Clarify that the driver is a CSI-2 receiver by supervised 
  s/interface/receiver/, thanks Laurent.
- Add entries in Kconfig and Makefile alphabetically instead of append.
- Rename struct rcar_csi2 member swap to lane_swap.
- Remove macros to wrap calls to dev_{dbg,info,warn,err}.
- Add wrappers for ioread32 and iowrite32.
- Remove unused interrupt handler, but keep checking in probe that there 
  are a interrupt define in DT.
- Rework how to wait for LP-11 state, thanks Laurent for the great idea!
- Remove unneeded delay in rcar_csi2_reset()
- Remove check for duplicated lane id:s from DT parsing. Broken out to a 
  separate patch adding this check directly to v4l2_of_parse_endpoint().
- Fixed rcar_csi2_start() to ask it's source subdevice for information 
  about pixel rate and frame format. With this change having
  {set,get}_fmt operations became redundant, it was only used for
  figuring out this out so dropped them.
- Tabulated frequency settings map.
- Dropped V4L2_SUBDEV_FL_HAS_DEVNODE it should never have been set.
- Switched from MEDIA_ENT_F_ATV_DECODER to 
  MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER as entity function. I can't
  find a more suitable function, and what the hardware do is to fetch
  video from an external chip and passes it on to a another SoC internal
  IP it's sort of a formatter.
- Break out DT documentation and code in two patches.

Changes since v3:
- Update DT binding documentation with input from Geert Uytterhoeven,
  thanks!

Changes since v2:
- Added media control pads as this is needed by the new rcar-vin driver.
- Update DT bindings after review comments and to add r8a7796 support.
- Add get_fmt handler.
- Fix media bus format error s/YUYV8/UYVY8/

Changes since v1:
- Drop dependency on a pad aware s_stream operation.
- Use the DT bindings format "renesas,<soctype>-<device>", thanks Geert
  for pointing this out.

1. http://elinux.org/R-Car/Tests:rcar-vin

Niklas Söderlund (2):
  media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver documentation
  media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver driver

 .../devicetree/bindings/media/rcar-csi2.txt        | 116 +++
 drivers/media/platform/rcar-vin/Kconfig            |  12 +
 drivers/media/platform/rcar-vin/Makefile           |   1 +
 drivers/media/platform/rcar-vin/rcar-csi2.c        | 867 +++++++++++++++++++++
 4 files changed, 996 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/media/rcar-csi2.txt
 create mode 100644 drivers/media/platform/rcar-vin/rcar-csi2.c

-- 
2.13.0

[PATCH v7 1/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver documentation

[Niklas Söderlund]

From: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>

Documentation for Renesas R-Car MIPI CSI-2 receiver. The CSI-2 receivers
are located between the video sources (CSI-2 transmitters) and the video
grabbers (VIN) on Gen3 of Renesas R-Car SoC.

Each CSI-2 device is connected to more then one VIN device which
simultaneously can receive video from the same CSI-2 device. Each VIN
device can also be connected to more then one CSI-2 device. The routing
of which link are used are controlled by the VIN devices. There are only
a few possible routes which are set by hardware limitations, which are
different for each SoC in the Gen3 family.

To work with the limitations of routing possibilities it is necessary
for the DT bindings to describe which VIN device is connected to which
CSI-2 device. This is why port 1 needs to to assign reg numbers for each
VIN device that be connected to it. To setup and to know which links are
valid for each SoC is the responsibility of the VIN driver since the
register to configure it belongs to the VIN hardware.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
---
 .../devicetree/bindings/media/rcar-csi2.txt        | 116 +++++++++++++++++++++
 1 file changed, 116 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/media/rcar-csi2.txt

diff --git a/Documentation/devicetree/bindings/media/rcar-csi2.txt b/Documentation/devicetree/bindings/media/rcar-csi2.txt
new file mode 100644
index 0000000000000000..f6e2027ee92b171a
--- /dev/null
+++ b/Documentation/devicetree/bindings/media/rcar-csi2.txt
@@ -0,0 +1,116 @@
+Renesas R-Car MIPI CSI-2
+------------------------
+
+The rcar-csi2 device provides MIPI CSI-2 capabilities for the Renesas R-Car
+family of devices. It is to be used in conjunction with the R-Car VIN module,
+which provides the video capture capabilities.
+
+ - compatible: Must be one or more of the following
+   - "renesas,r8a7795-csi2" for the R8A7795 device.
+   - "renesas,r8a7796-csi2" for the R8A7796 device.
+   - "renesas,rcar-gen3-csi2" for a generic R-Car Gen3 compatible device.
+
+   When compatible with a generic version nodes must list the
+   SoC-specific version corresponding to the platform first
+   followed by the generic version.
+
+ - reg: the register base and size for the device registers
+ - interrupts: the interrupt for the device
+ - clocks: Reference to the parent clock
+
+The device node should contain two 'port' child nodes according to the
+bindings defined in Documentation/devicetree/bindings/media/
+video-interfaces.txt. Port 0 should connect the node that is the video
+source for to the CSI-2. Port 1 should connect all the R-Car VIN
+modules, which can make use of the CSI-2 module.
+
+- Port 0 - Video source
+	- Reg 0 - sub-node describing the endpoint that is the video source
+
+- Port 1 - VIN instances
+	- Reg 0 - sub-node describing the endpoint that is VIN0
+	- Reg 1 - sub-node describing the endpoint that is VIN1
+	- Reg 2 - sub-node describing the endpoint that is VIN2
+	- Reg 3 - sub-node describing the endpoint that is VIN3
+	- Reg 4 - sub-node describing the endpoint that is VIN4
+	- Reg 5 - sub-node describing the endpoint that is VIN5
+	- Reg 6 - sub-node describing the endpoint that is VIN6
+	- Reg 7 - sub-node describing the endpoint that is VIN7
+
+Example:
+
+/* SoC properties */
+
+	 csi20: csi2@fea80000 {
+		 compatible = "renesas,r8a7796-csi2";
+		 reg = <0 0xfea80000 0 0x10000>;
+		 interrupts = <0 184 IRQ_TYPE_LEVEL_HIGH>;
+		 clocks = <&cpg CPG_MOD 714>;
+		 power-domains = <&sysc R8A7796_PD_ALWAYS_ON>;
+		 status = "disabled";
+
+		 ports {
+			 #address-cells = <1>;
+			 #size-cells = <0>;
+
+			 port@1 {
+				 #address-cells = <1>;
+				 #size-cells = <0>;
+
+				 reg = <1>;
+
+				 csi20vin0: endpoint@0 {
+					 reg = <0>;
+					 remote-endpoint = <&vin0csi20>;
+				 };
+				 csi20vin1: endpoint@1 {
+					 reg = <1>;
+					 remote-endpoint = <&vin1csi20>;
+				 };
+				 csi20vin2: endpoint@2 {
+					 reg = <2>;
+					 remote-endpoint = <&vin2csi20>;
+				 };
+				 csi20vin3: endpoint@3 {
+					 reg = <3>;
+					 remote-endpoint = <&vin3csi20>;
+				 };
+				 csi20vin4: endpoint@4 {
+					 reg = <4>;
+					 remote-endpoint = <&vin4csi20>;
+				 };
+				 csi20vin5: endpoint@5 {
+					 reg = <5>;
+					 remote-endpoint = <&vin5csi20>;
+				 };
+				 csi20vin6: endpoint@6 {
+					 reg = <6>;
+					 remote-endpoint = <&vin6csi20>;
+				 };
+				 csi20vin7: endpoint@7 {
+					 reg = <7>;
+					 remote-endpoint = <&vin7csi20>;
+				 };
+			 };
+		 };
+	 };
+
+/* Board properties */
+
+	&csi20 {
+		status = "okay";
+
+		ports {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			port@0 {
+				reg = <0>;
+				csi20_in: endpoint@0 {
+					clock-lanes = <0>;
+					data-lanes = <1>;
+					remote-endpoint = <&adv7482_txb>;
+				};
+			};
+		};
+	};
-- 
2.13.0

Re: [PATCH v7 1/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver documentation

[Sakari Ailus]

Hi Niklas,

On Wed, May 24, 2017 at 02:13:52AM +0200, Niklas Söderlund wrote:
> From: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> 
> Documentation for Renesas R-Car MIPI CSI-2 receiver. The CSI-2 receivers
> are located between the video sources (CSI-2 transmitters) and the video
> grabbers (VIN) on Gen3 of Renesas R-Car SoC.
> 
> Each CSI-2 device is connected to more then one VIN device which
> simultaneously can receive video from the same CSI-2 device. Each VIN
> device can also be connected to more then one CSI-2 device. The routing
> of which link are used are controlled by the VIN devices. There are only
> a few possible routes which are set by hardware limitations, which are
> different for each SoC in the Gen3 family.
> 
> To work with the limitations of routing possibilities it is necessary
> for the DT bindings to describe which VIN device is connected to which
> CSI-2 device. This is why port 1 needs to to assign reg numbers for each
> VIN device that be connected to it. To setup and to know which links are
> valid for each SoC is the responsibility of the VIN driver since the
> register to configure it belongs to the VIN hardware.
> 
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> ---
>  .../devicetree/bindings/media/rcar-csi2.txt        | 116 +++++++++++++++++++++
>  1 file changed, 116 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/media/rcar-csi2.txt
> 
> diff --git a/Documentation/devicetree/bindings/media/rcar-csi2.txt b/Documentation/devicetree/bindings/media/rcar-csi2.txt
> new file mode 100644
> index 0000000000000000..f6e2027ee92b171a
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/media/rcar-csi2.txt
> @@ -0,0 +1,116 @@
> +Renesas R-Car MIPI CSI-2
> +------------------------
> +
> +The rcar-csi2 device provides MIPI CSI-2 capabilities for the Renesas R-Car
> +family of devices. It is to be used in conjunction with the R-Car VIN module,
> +which provides the video capture capabilities.
> +
> + - compatible: Must be one or more of the following
> +   - "renesas,r8a7795-csi2" for the R8A7795 device.
> +   - "renesas,r8a7796-csi2" for the R8A7796 device.
> +   - "renesas,rcar-gen3-csi2" for a generic R-Car Gen3 compatible device.
> +
> +   When compatible with a generic version nodes must list the
> +   SoC-specific version corresponding to the platform first
> +   followed by the generic version.
> +
> + - reg: the register base and size for the device registers
> + - interrupts: the interrupt for the device
> + - clocks: Reference to the parent clock
> +
> +The device node should contain two 'port' child nodes according to the
> +bindings defined in Documentation/devicetree/bindings/media/
> +video-interfaces.txt. Port 0 should connect the node that is the video
> +source for to the CSI-2. Port 1 should connect all the R-Car VIN
> +modules, which can make use of the CSI-2 module.

Should or shall?

I guess you could add that it is possible to leave them unconnected, too.

> +
> +- Port 0 - Video source
> +	- Reg 0 - sub-node describing the endpoint that is the video source

Which endpoint properties are mandatory for the receiver? Which ones are
optional? (I.e. it shouldn't be necessary to read driver code to write board
description.)

> +
> +- Port 1 - VIN instances
> +	- Reg 0 - sub-node describing the endpoint that is VIN0
> +	- Reg 1 - sub-node describing the endpoint that is VIN1
> +	- Reg 2 - sub-node describing the endpoint that is VIN2
> +	- Reg 3 - sub-node describing the endpoint that is VIN3
> +	- Reg 4 - sub-node describing the endpoint that is VIN4
> +	- Reg 5 - sub-node describing the endpoint that is VIN5
> +	- Reg 6 - sub-node describing the endpoint that is VIN6
> +	- Reg 7 - sub-node describing the endpoint that is VIN7
> +
> +Example:
> +
> +/* SoC properties */
> +
> +	 csi20: csi2@fea80000 {
> +		 compatible = "renesas,r8a7796-csi2";
> +		 reg = <0 0xfea80000 0 0x10000>;
> +		 interrupts = <0 184 IRQ_TYPE_LEVEL_HIGH>;
> +		 clocks = <&cpg CPG_MOD 714>;
> +		 power-domains = <&sysc R8A7796_PD_ALWAYS_ON>;
> +		 status = "disabled";
> +
> +		 ports {
> +			 #address-cells = <1>;
> +			 #size-cells = <0>;
> +
> +			 port@1 {
> +				 #address-cells = <1>;
> +				 #size-cells = <0>;
> +
> +				 reg = <1>;
> +
> +				 csi20vin0: endpoint@0 {
> +					 reg = <0>;
> +					 remote-endpoint = <&vin0csi20>;
> +				 };
> +				 csi20vin1: endpoint@1 {
> +					 reg = <1>;
> +					 remote-endpoint = <&vin1csi20>;
> +				 };
> +				 csi20vin2: endpoint@2 {
> +					 reg = <2>;
> +					 remote-endpoint = <&vin2csi20>;
> +				 };
> +				 csi20vin3: endpoint@3 {
> +					 reg = <3>;
> +					 remote-endpoint = <&vin3csi20>;
> +				 };
> +				 csi20vin4: endpoint@4 {
> +					 reg = <4>;
> +					 remote-endpoint = <&vin4csi20>;
> +				 };
> +				 csi20vin5: endpoint@5 {
> +					 reg = <5>;
> +					 remote-endpoint = <&vin5csi20>;
> +				 };
> +				 csi20vin6: endpoint@6 {
> +					 reg = <6>;
> +					 remote-endpoint = <&vin6csi20>;
> +				 };
> +				 csi20vin7: endpoint@7 {
> +					 reg = <7>;
> +					 remote-endpoint = <&vin7csi20>;
> +				 };
> +			 };
> +		 };
> +	 };
> +
> +/* Board properties */
> +
> +	&csi20 {
> +		status = "okay";
> +
> +		ports {
> +			#address-cells = <1>;
> +			#size-cells = <0>;
> +
> +			port@0 {
> +				reg = <0>;
> +				csi20_in: endpoint@0 {
> +					clock-lanes = <0>;
> +					data-lanes = <1>;
> +					remote-endpoint = <&adv7482_txb>;
> +				};
> +			};
> +		};
> +	};

-- 
Kind regards,

Sakari Ailus
e-mail: sakari.ailus@iki.fi	XMPP: sailus@retiisi.org.uk

Re: [PATCH v7 1/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver documentation

[Sakari Ailus]

Hi Niklas,

On Wed, May 24, 2017 at 02:13:52AM +0200, Niklas S�derlund wrote:
> From: Niklas S�derlund <niklas.soderlund+renesas@ragnatech.se>
> 
> Documentation for Renesas R-Car MIPI CSI-2 receiver. The CSI-2 receivers
> are located between the video sources (CSI-2 transmitters) and the video
> grabbers (VIN) on Gen3 of Renesas R-Car SoC.
> 
> Each CSI-2 device is connected to more then one VIN device which
> simultaneously can receive video from the same CSI-2 device. Each VIN
> device can also be connected to more then one CSI-2 device. The routing
> of which link are used are controlled by the VIN devices. There are only
> a few possible routes which are set by hardware limitations, which are
> different for each SoC in the Gen3 family.
> 
> To work with the limitations of routing possibilities it is necessary
> for the DT bindings to describe which VIN device is connected to which
> CSI-2 device. This is why port 1 needs to to assign reg numbers for each
> VIN device that be connected to it. To setup and to know which links are
> valid for each SoC is the responsibility of the VIN driver since the
> register to configure it belongs to the VIN hardware.
> 
> Signed-off-by: Niklas S�derlund <niklas.soderlund+renesas@ragnatech.se>
> ---
>  .../devicetree/bindings/media/rcar-csi2.txt        | 116 +++++++++++++++++++++
>  1 file changed, 116 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/media/rcar-csi2.txt
> 
> diff --git a/Documentation/devicetree/bindings/media/rcar-csi2.txt b/Documentation/devicetree/bindings/media/rcar-csi2.txt
> new file mode 100644
> index 0000000000000000..f6e2027ee92b171a
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/media/rcar-csi2.txt
> @@ -0,0 +1,116 @@
> +Renesas R-Car MIPI CSI-2
> +------------------------
> +
> +The rcar-csi2 device provides MIPI CSI-2 capabilities for the Renesas R-Car
> +family of devices. It is to be used in conjunction with the R-Car VIN module,
> +which provides the video capture capabilities.
> +
> + - compatible: Must be one or more of the following
> +   - "renesas,r8a7795-csi2" for the R8A7795 device.
> +   - "renesas,r8a7796-csi2" for the R8A7796 device.
> +   - "renesas,rcar-gen3-csi2" for a generic R-Car Gen3 compatible device.
> +
> +   When compatible with a generic version nodes must list the
> +   SoC-specific version corresponding to the platform first
> +   followed by the generic version.
> +
> + - reg: the register base and size for the device registers
> + - interrupts: the interrupt for the device
> + - clocks: Reference to the parent clock
> +
> +The device node should contain two 'port' child nodes according to the
> +bindings defined in Documentation/devicetree/bindings/media/
> +video-interfaces.txt. Port 0 should connect the node that is the video
> +source for to the CSI-2. Port 1 should connect all the R-Car VIN
> +modules, which can make use of the CSI-2 module.

Should or shall?

I guess you could add that it is possible to leave them unconnected, too.

> +
> +- Port 0 - Video source
> +	- Reg 0 - sub-node describing the endpoint that is the video source

Which endpoint properties are mandatory for the receiver? Which ones are
optional? (I.e. it shouldn't be necessary to read driver code to write board
description.)

> +
> +- Port 1 - VIN instances
> +	- Reg 0 - sub-node describing the endpoint that is VIN0
> +	- Reg 1 - sub-node describing the endpoint that is VIN1
> +	- Reg 2 - sub-node describing the endpoint that is VIN2
> +	- Reg 3 - sub-node describing the endpoint that is VIN3
> +	- Reg 4 - sub-node describing the endpoint that is VIN4
> +	- Reg 5 - sub-node describing the endpoint that is VIN5
> +	- Reg 6 - sub-node describing the endpoint that is VIN6
> +	- Reg 7 - sub-node describing the endpoint that is VIN7
> +
> +Example:
> +
> +/* SoC properties */
> +
> +	 csi20: csi2@fea80000 {
> +		 compatible = "renesas,r8a7796-csi2";
> +		 reg = <0 0xfea80000 0 0x10000>;
> +		 interrupts = <0 184 IRQ_TYPE_LEVEL_HIGH>;
> +		 clocks = <&cpg CPG_MOD 714>;
> +		 power-domains = <&sysc R8A7796_PD_ALWAYS_ON>;
> +		 status = "disabled";
> +
> +		 ports {
> +			 #address-cells = <1>;
> +			 #size-cells = <0>;
> +
> +			 port@1 {
> +				 #address-cells = <1>;
> +				 #size-cells = <0>;
> +
> +				 reg = <1>;
> +
> +				 csi20vin0: endpoint@0 {
> +					 reg = <0>;
> +					 remote-endpoint = <&vin0csi20>;
> +				 };
> +				 csi20vin1: endpoint@1 {
> +					 reg = <1>;
> +					 remote-endpoint = <&vin1csi20>;
> +				 };
> +				 csi20vin2: endpoint@2 {
> +					 reg = <2>;
> +					 remote-endpoint = <&vin2csi20>;
> +				 };
> +				 csi20vin3: endpoint@3 {
> +					 reg = <3>;
> +					 remote-endpoint = <&vin3csi20>;
> +				 };
> +				 csi20vin4: endpoint@4 {
> +					 reg = <4>;
> +					 remote-endpoint = <&vin4csi20>;
> +				 };
> +				 csi20vin5: endpoint@5 {
> +					 reg = <5>;
> +					 remote-endpoint = <&vin5csi20>;
> +				 };
> +				 csi20vin6: endpoint@6 {
> +					 reg = <6>;
> +					 remote-endpoint = <&vin6csi20>;
> +				 };
> +				 csi20vin7: endpoint@7 {
> +					 reg = <7>;
> +					 remote-endpoint = <&vin7csi20>;
> +				 };
> +			 };
> +		 };
> +	 };
> +
> +/* Board properties */
> +
> +	&csi20 {
> +		status = "okay";
> +
> +		ports {
> +			#address-cells = <1>;
> +			#size-cells = <0>;
> +
> +			port@0 {
> +				reg = <0>;
> +				csi20_in: endpoint@0 {
> +					clock-lanes = <0>;
> +					data-lanes = <1>;
> +					remote-endpoint = <&adv7482_txb>;
> +				};
> +			};
> +		};
> +	};

-- 
Kind regards,

Sakari Ailus
e-mail: sakari.ailus@iki.fi	XMPP: sailus@retiisi.org.uk

Re: [PATCH v7 1/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver documentation

[Niklas Söderlund]

Hi Sakari,

Thanks for your feedback.

On 2017-05-29 14:16:25 +0300, Sakari Ailus wrote:
> Hi Niklas,
> 
> On Wed, May 24, 2017 at 02:13:52AM +0200, Niklas Söderlund wrote:
> > From: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> > 
> > Documentation for Renesas R-Car MIPI CSI-2 receiver. The CSI-2 receivers
> > are located between the video sources (CSI-2 transmitters) and the video
> > grabbers (VIN) on Gen3 of Renesas R-Car SoC.
> > 
> > Each CSI-2 device is connected to more then one VIN device which
> > simultaneously can receive video from the same CSI-2 device. Each VIN
> > device can also be connected to more then one CSI-2 device. The routing
> > of which link are used are controlled by the VIN devices. There are only
> > a few possible routes which are set by hardware limitations, which are
> > different for each SoC in the Gen3 family.
> > 
> > To work with the limitations of routing possibilities it is necessary
> > for the DT bindings to describe which VIN device is connected to which
> > CSI-2 device. This is why port 1 needs to to assign reg numbers for each
> > VIN device that be connected to it. To setup and to know which links are
> > valid for each SoC is the responsibility of the VIN driver since the
> > register to configure it belongs to the VIN hardware.
> > 
> > Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> > ---
> >  .../devicetree/bindings/media/rcar-csi2.txt        | 116 +++++++++++++++++++++
> >  1 file changed, 116 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/media/rcar-csi2.txt
> > 
> > diff --git a/Documentation/devicetree/bindings/media/rcar-csi2.txt b/Documentation/devicetree/bindings/media/rcar-csi2.txt
> > new file mode 100644
> > index 0000000000000000..f6e2027ee92b171a
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/media/rcar-csi2.txt
> > @@ -0,0 +1,116 @@
> > +Renesas R-Car MIPI CSI-2
> > +------------------------
> > +
> > +The rcar-csi2 device provides MIPI CSI-2 capabilities for the Renesas R-Car
> > +family of devices. It is to be used in conjunction with the R-Car VIN module,
> > +which provides the video capture capabilities.
> > +
> > + - compatible: Must be one or more of the following
> > +   - "renesas,r8a7795-csi2" for the R8A7795 device.
> > +   - "renesas,r8a7796-csi2" for the R8A7796 device.
> > +   - "renesas,rcar-gen3-csi2" for a generic R-Car Gen3 compatible device.
> > +
> > +   When compatible with a generic version nodes must list the
> > +   SoC-specific version corresponding to the platform first
> > +   followed by the generic version.
> > +
> > + - reg: the register base and size for the device registers
> > + - interrupts: the interrupt for the device
> > + - clocks: Reference to the parent clock
> > +
> > +The device node should contain two 'port' child nodes according to the
> > +bindings defined in Documentation/devicetree/bindings/media/
> > +video-interfaces.txt. Port 0 should connect the node that is the video
> > +source for to the CSI-2. Port 1 should connect all the R-Car VIN
> > +modules, which can make use of the CSI-2 module.
> 
> Should or shall?
> 
> I guess you could add that it is possible to leave them unconnected, too.

Which ports/endpoints are you talking about? In my mind it's not allowed 
to leave them unconnected.

If there ever is a system with only 4 VIN instances (I'm not aware of 
any such system) then yes the endpoints for those VIN not present in the 
system in port 1 should be left unconnected but other then that they 
should all be mandatory right? Or am I missing something?

> 
> > +
> > +- Port 0 - Video source
> > +	- Reg 0 - sub-node describing the endpoint that is the video source
> 
> Which endpoint properties are mandatory for the receiver? Which ones are
> optional? (I.e. it shouldn't be necessary to read driver code to write board
> description.)

I will add a note that all endpoints in port 0 are mandatory and that 
all endpoints that represents a connection to a VIN instance in the 
system is mandatory for next version. Thanks I did not think about this 
possibility.

> 
> > +
> > +- Port 1 - VIN instances
> > +	- Reg 0 - sub-node describing the endpoint that is VIN0
> > +	- Reg 1 - sub-node describing the endpoint that is VIN1
> > +	- Reg 2 - sub-node describing the endpoint that is VIN2
> > +	- Reg 3 - sub-node describing the endpoint that is VIN3
> > +	- Reg 4 - sub-node describing the endpoint that is VIN4
> > +	- Reg 5 - sub-node describing the endpoint that is VIN5
> > +	- Reg 6 - sub-node describing the endpoint that is VIN6
> > +	- Reg 7 - sub-node describing the endpoint that is VIN7
> > +
> > +Example:
> > +
> > +/* SoC properties */
> > +
> > +	 csi20: csi2@fea80000 {
> > +		 compatible = "renesas,r8a7796-csi2";
> > +		 reg = <0 0xfea80000 0 0x10000>;
> > +		 interrupts = <0 184 IRQ_TYPE_LEVEL_HIGH>;
> > +		 clocks = <&cpg CPG_MOD 714>;
> > +		 power-domains = <&sysc R8A7796_PD_ALWAYS_ON>;
> > +		 status = "disabled";
> > +
> > +		 ports {
> > +			 #address-cells = <1>;
> > +			 #size-cells = <0>;
> > +
> > +			 port@1 {
> > +				 #address-cells = <1>;
> > +				 #size-cells = <0>;
> > +
> > +				 reg = <1>;
> > +
> > +				 csi20vin0: endpoint@0 {
> > +					 reg = <0>;
> > +					 remote-endpoint = <&vin0csi20>;
> > +				 };
> > +				 csi20vin1: endpoint@1 {
> > +					 reg = <1>;
> > +					 remote-endpoint = <&vin1csi20>;
> > +				 };
> > +				 csi20vin2: endpoint@2 {
> > +					 reg = <2>;
> > +					 remote-endpoint = <&vin2csi20>;
> > +				 };
> > +				 csi20vin3: endpoint@3 {
> > +					 reg = <3>;
> > +					 remote-endpoint = <&vin3csi20>;
> > +				 };
> > +				 csi20vin4: endpoint@4 {
> > +					 reg = <4>;
> > +					 remote-endpoint = <&vin4csi20>;
> > +				 };
> > +				 csi20vin5: endpoint@5 {
> > +					 reg = <5>;
> > +					 remote-endpoint = <&vin5csi20>;
> > +				 };
> > +				 csi20vin6: endpoint@6 {
> > +					 reg = <6>;
> > +					 remote-endpoint = <&vin6csi20>;
> > +				 };
> > +				 csi20vin7: endpoint@7 {
> > +					 reg = <7>;
> > +					 remote-endpoint = <&vin7csi20>;
> > +				 };
> > +			 };
> > +		 };
> > +	 };
> > +
> > +/* Board properties */
> > +
> > +	&csi20 {
> > +		status = "okay";
> > +
> > +		ports {
> > +			#address-cells = <1>;
> > +			#size-cells = <0>;
> > +
> > +			port@0 {
> > +				reg = <0>;
> > +				csi20_in: endpoint@0 {
> > +					clock-lanes = <0>;
> > +					data-lanes = <1>;
> > +					remote-endpoint = <&adv7482_txb>;
> > +				};
> > +			};
> > +		};
> > +	};
> 
> -- 
> Kind regards,
> 
> Sakari Ailus
> e-mail: sakari.ailus@iki.fi	XMPP: sailus@retiisi.org.uk

-- 
Regards,
Niklas Söderlund

Re: [PATCH v7 1/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver documentation

[Niklas Söderlund]

Hi Sakari,

Thanks for your feedback.

On 2017-05-29 14:16:25 +0300, Sakari Ailus wrote:
> Hi Niklas,
> 
> On Wed, May 24, 2017 at 02:13:52AM +0200, Niklas S�derlund wrote:
> > From: Niklas S�derlund <niklas.soderlund+renesas@ragnatech.se>
> > 
> > Documentation for Renesas R-Car MIPI CSI-2 receiver. The CSI-2 receivers
> > are located between the video sources (CSI-2 transmitters) and the video
> > grabbers (VIN) on Gen3 of Renesas R-Car SoC.
> > 
> > Each CSI-2 device is connected to more then one VIN device which
> > simultaneously can receive video from the same CSI-2 device. Each VIN
> > device can also be connected to more then one CSI-2 device. The routing
> > of which link are used are controlled by the VIN devices. There are only
> > a few possible routes which are set by hardware limitations, which are
> > different for each SoC in the Gen3 family.
> > 
> > To work with the limitations of routing possibilities it is necessary
> > for the DT bindings to describe which VIN device is connected to which
> > CSI-2 device. This is why port 1 needs to to assign reg numbers for each
> > VIN device that be connected to it. To setup and to know which links are
> > valid for each SoC is the responsibility of the VIN driver since the
> > register to configure it belongs to the VIN hardware.
> > 
> > Signed-off-by: Niklas S�derlund <niklas.soderlund+renesas@ragnatech.se>
> > ---
> >  .../devicetree/bindings/media/rcar-csi2.txt        | 116 +++++++++++++++++++++
> >  1 file changed, 116 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/media/rcar-csi2.txt
> > 
> > diff --git a/Documentation/devicetree/bindings/media/rcar-csi2.txt b/Documentation/devicetree/bindings/media/rcar-csi2.txt
> > new file mode 100644
> > index 0000000000000000..f6e2027ee92b171a
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/media/rcar-csi2.txt
> > @@ -0,0 +1,116 @@
> > +Renesas R-Car MIPI CSI-2
> > +------------------------
> > +
> > +The rcar-csi2 device provides MIPI CSI-2 capabilities for the Renesas R-Car
> > +family of devices. It is to be used in conjunction with the R-Car VIN module,
> > +which provides the video capture capabilities.
> > +
> > + - compatible: Must be one or more of the following
> > +   - "renesas,r8a7795-csi2" for the R8A7795 device.
> > +   - "renesas,r8a7796-csi2" for the R8A7796 device.
> > +   - "renesas,rcar-gen3-csi2" for a generic R-Car Gen3 compatible device.
> > +
> > +   When compatible with a generic version nodes must list the
> > +   SoC-specific version corresponding to the platform first
> > +   followed by the generic version.
> > +
> > + - reg: the register base and size for the device registers
> > + - interrupts: the interrupt for the device
> > + - clocks: Reference to the parent clock
> > +
> > +The device node should contain two 'port' child nodes according to the
> > +bindings defined in Documentation/devicetree/bindings/media/
> > +video-interfaces.txt. Port 0 should connect the node that is the video
> > +source for to the CSI-2. Port 1 should connect all the R-Car VIN
> > +modules, which can make use of the CSI-2 module.
> 
> Should or shall?
> 
> I guess you could add that it is possible to leave them unconnected, too.

Which ports/endpoints are you talking about? In my mind it's not allowed 
to leave them unconnected.

If there ever is a system with only 4 VIN instances (I'm not aware of 
any such system) then yes the endpoints for those VIN not present in the 
system in port 1 should be left unconnected but other then that they 
should all be mandatory right? Or am I missing something?

> 
> > +
> > +- Port 0 - Video source
> > +	- Reg 0 - sub-node describing the endpoint that is the video source
> 
> Which endpoint properties are mandatory for the receiver? Which ones are
> optional? (I.e. it shouldn't be necessary to read driver code to write board
> description.)

I will add a note that all endpoints in port 0 are mandatory and that 
all endpoints that represents a connection to a VIN instance in the 
system is mandatory for next version. Thanks I did not think about this 
possibility.

> 
> > +
> > +- Port 1 - VIN instances
> > +	- Reg 0 - sub-node describing the endpoint that is VIN0
> > +	- Reg 1 - sub-node describing the endpoint that is VIN1
> > +	- Reg 2 - sub-node describing the endpoint that is VIN2
> > +	- Reg 3 - sub-node describing the endpoint that is VIN3
> > +	- Reg 4 - sub-node describing the endpoint that is VIN4
> > +	- Reg 5 - sub-node describing the endpoint that is VIN5
> > +	- Reg 6 - sub-node describing the endpoint that is VIN6
> > +	- Reg 7 - sub-node describing the endpoint that is VIN7
> > +
> > +Example:
> > +
> > +/* SoC properties */
> > +
> > +	 csi20: csi2@fea80000 {
> > +		 compatible = "renesas,r8a7796-csi2";
> > +		 reg = <0 0xfea80000 0 0x10000>;
> > +		 interrupts = <0 184 IRQ_TYPE_LEVEL_HIGH>;
> > +		 clocks = <&cpg CPG_MOD 714>;
> > +		 power-domains = <&sysc R8A7796_PD_ALWAYS_ON>;
> > +		 status = "disabled";
> > +
> > +		 ports {
> > +			 #address-cells = <1>;
> > +			 #size-cells = <0>;
> > +
> > +			 port@1 {
> > +				 #address-cells = <1>;
> > +				 #size-cells = <0>;
> > +
> > +				 reg = <1>;
> > +
> > +				 csi20vin0: endpoint@0 {
> > +					 reg = <0>;
> > +					 remote-endpoint = <&vin0csi20>;
> > +				 };
> > +				 csi20vin1: endpoint@1 {
> > +					 reg = <1>;
> > +					 remote-endpoint = <&vin1csi20>;
> > +				 };
> > +				 csi20vin2: endpoint@2 {
> > +					 reg = <2>;
> > +					 remote-endpoint = <&vin2csi20>;
> > +				 };
> > +				 csi20vin3: endpoint@3 {
> > +					 reg = <3>;
> > +					 remote-endpoint = <&vin3csi20>;
> > +				 };
> > +				 csi20vin4: endpoint@4 {
> > +					 reg = <4>;
> > +					 remote-endpoint = <&vin4csi20>;
> > +				 };
> > +				 csi20vin5: endpoint@5 {
> > +					 reg = <5>;
> > +					 remote-endpoint = <&vin5csi20>;
> > +				 };
> > +				 csi20vin6: endpoint@6 {
> > +					 reg = <6>;
> > +					 remote-endpoint = <&vin6csi20>;
> > +				 };
> > +				 csi20vin7: endpoint@7 {
> > +					 reg = <7>;
> > +					 remote-endpoint = <&vin7csi20>;
> > +				 };
> > +			 };
> > +		 };
> > +	 };
> > +
> > +/* Board properties */
> > +
> > +	&csi20 {
> > +		status = "okay";
> > +
> > +		ports {
> > +			#address-cells = <1>;
> > +			#size-cells = <0>;
> > +
> > +			port@0 {
> > +				reg = <0>;
> > +				csi20_in: endpoint@0 {
> > +					clock-lanes = <0>;
> > +					data-lanes = <1>;
> > +					remote-endpoint = <&adv7482_txb>;
> > +				};
> > +			};
> > +		};
> > +	};
> 
> -- 
> Kind regards,
> 
> Sakari Ailus
> e-mail: sakari.ailus@iki.fi	XMPP: sailus@retiisi.org.uk

-- 
Regards,
Niklas S�derlund

Re: [PATCH v7 1/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver documentation

[Sakari Ailus]

Hi Niklas,

On Tue, Jun 13, 2017 at 06:50:14PM +0200, Niklas Söderlund wrote:
> Hi Sakari,
> 
> Thanks for your feedback.
> 
> On 2017-05-29 14:16:25 +0300, Sakari Ailus wrote:
> > Hi Niklas,
> > 
> > On Wed, May 24, 2017 at 02:13:52AM +0200, Niklas Söderlund wrote:
> > > From: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> > > 
> > > Documentation for Renesas R-Car MIPI CSI-2 receiver. The CSI-2 receivers
> > > are located between the video sources (CSI-2 transmitters) and the video
> > > grabbers (VIN) on Gen3 of Renesas R-Car SoC.
> > > 
> > > Each CSI-2 device is connected to more then one VIN device which
> > > simultaneously can receive video from the same CSI-2 device. Each VIN
> > > device can also be connected to more then one CSI-2 device. The routing
> > > of which link are used are controlled by the VIN devices. There are only
> > > a few possible routes which are set by hardware limitations, which are
> > > different for each SoC in the Gen3 family.
> > > 
> > > To work with the limitations of routing possibilities it is necessary
> > > for the DT bindings to describe which VIN device is connected to which
> > > CSI-2 device. This is why port 1 needs to to assign reg numbers for each
> > > VIN device that be connected to it. To setup and to know which links are
> > > valid for each SoC is the responsibility of the VIN driver since the
> > > register to configure it belongs to the VIN hardware.
> > > 
> > > Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> > > ---
> > >  .../devicetree/bindings/media/rcar-csi2.txt        | 116 +++++++++++++++++++++
> > >  1 file changed, 116 insertions(+)
> > >  create mode 100644 Documentation/devicetree/bindings/media/rcar-csi2.txt
> > > 
> > > diff --git a/Documentation/devicetree/bindings/media/rcar-csi2.txt b/Documentation/devicetree/bindings/media/rcar-csi2.txt
> > > new file mode 100644
> > > index 0000000000000000..f6e2027ee92b171a
> > > --- /dev/null
> > > +++ b/Documentation/devicetree/bindings/media/rcar-csi2.txt
> > > @@ -0,0 +1,116 @@
> > > +Renesas R-Car MIPI CSI-2
> > > +------------------------
> > > +
> > > +The rcar-csi2 device provides MIPI CSI-2 capabilities for the Renesas R-Car
> > > +family of devices. It is to be used in conjunction with the R-Car VIN module,
> > > +which provides the video capture capabilities.
> > > +
> > > + - compatible: Must be one or more of the following
> > > +   - "renesas,r8a7795-csi2" for the R8A7795 device.
> > > +   - "renesas,r8a7796-csi2" for the R8A7796 device.
> > > +   - "renesas,rcar-gen3-csi2" for a generic R-Car Gen3 compatible device.
> > > +
> > > +   When compatible with a generic version nodes must list the
> > > +   SoC-specific version corresponding to the platform first
> > > +   followed by the generic version.
> > > +
> > > + - reg: the register base and size for the device registers
> > > + - interrupts: the interrupt for the device
> > > + - clocks: Reference to the parent clock
> > > +
> > > +The device node should contain two 'port' child nodes according to the
> > > +bindings defined in Documentation/devicetree/bindings/media/
> > > +video-interfaces.txt. Port 0 should connect the node that is the video
> > > +source for to the CSI-2. Port 1 should connect all the R-Car VIN
> > > +modules, which can make use of the CSI-2 module.
> > 
> > Should or shall?
> > 
> > I guess you could add that it is possible to leave them unconnected, too.
> 
> Which ports/endpoints are you talking about? In my mind it's not allowed 
> to leave them unconnected.
> 
> If there ever is a system with only 4 VIN instances (I'm not aware of 
> any such system) then yes the endpoints for those VIN not present in the 
> system in port 1 should be left unconnected but other then that they 
> should all be mandatory right? Or am I missing something?

I think so, yes. Then "shall" is right, isn't it?

> 
> > 
> > > +
> > > +- Port 0 - Video source
> > > +	- Reg 0 - sub-node describing the endpoint that is the video source
> > 
> > Which endpoint properties are mandatory for the receiver? Which ones are
> > optional? (I.e. it shouldn't be necessary to read driver code to write board
> > description.)
> 
> I will add a note that all endpoints in port 0 are mandatory and that 
> all endpoints that represents a connection to a VIN instance in the 
> system is mandatory for next version. Thanks I did not think about this 
> possibility.

Please list the mandatory and optional properties, too. Not just the
endpoints.

-- 
Hälsningar,

Sakari Ailus
e-mail: sakari.ailus@iki.fi	XMPP: sailus@retiisi.org.uk

Re: [PATCH v7 1/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver documentation

[Sakari Ailus]

Hi Niklas,

On Tue, Jun 13, 2017 at 06:50:14PM +0200, Niklas S�derlund wrote:
> Hi Sakari,
> 
> Thanks for your feedback.
> 
> On 2017-05-29 14:16:25 +0300, Sakari Ailus wrote:
> > Hi Niklas,
> > 
> > On Wed, May 24, 2017 at 02:13:52AM +0200, Niklas S�derlund wrote:
> > > From: Niklas S�derlund <niklas.soderlund+renesas@ragnatech.se>
> > > 
> > > Documentation for Renesas R-Car MIPI CSI-2 receiver. The CSI-2 receivers
> > > are located between the video sources (CSI-2 transmitters) and the video
> > > grabbers (VIN) on Gen3 of Renesas R-Car SoC.
> > > 
> > > Each CSI-2 device is connected to more then one VIN device which
> > > simultaneously can receive video from the same CSI-2 device. Each VIN
> > > device can also be connected to more then one CSI-2 device. The routing
> > > of which link are used are controlled by the VIN devices. There are only
> > > a few possible routes which are set by hardware limitations, which are
> > > different for each SoC in the Gen3 family.
> > > 
> > > To work with the limitations of routing possibilities it is necessary
> > > for the DT bindings to describe which VIN device is connected to which
> > > CSI-2 device. This is why port 1 needs to to assign reg numbers for each
> > > VIN device that be connected to it. To setup and to know which links are
> > > valid for each SoC is the responsibility of the VIN driver since the
> > > register to configure it belongs to the VIN hardware.
> > > 
> > > Signed-off-by: Niklas S�derlund <niklas.soderlund+renesas@ragnatech.se>
> > > ---
> > >  .../devicetree/bindings/media/rcar-csi2.txt        | 116 +++++++++++++++++++++
> > >  1 file changed, 116 insertions(+)
> > >  create mode 100644 Documentation/devicetree/bindings/media/rcar-csi2.txt
> > > 
> > > diff --git a/Documentation/devicetree/bindings/media/rcar-csi2.txt b/Documentation/devicetree/bindings/media/rcar-csi2.txt
> > > new file mode 100644
> > > index 0000000000000000..f6e2027ee92b171a
> > > --- /dev/null
> > > +++ b/Documentation/devicetree/bindings/media/rcar-csi2.txt
> > > @@ -0,0 +1,116 @@
> > > +Renesas R-Car MIPI CSI-2
> > > +------------------------
> > > +
> > > +The rcar-csi2 device provides MIPI CSI-2 capabilities for the Renesas R-Car
> > > +family of devices. It is to be used in conjunction with the R-Car VIN module,
> > > +which provides the video capture capabilities.
> > > +
> > > + - compatible: Must be one or more of the following
> > > +   - "renesas,r8a7795-csi2" for the R8A7795 device.
> > > +   - "renesas,r8a7796-csi2" for the R8A7796 device.
> > > +   - "renesas,rcar-gen3-csi2" for a generic R-Car Gen3 compatible device.
> > > +
> > > +   When compatible with a generic version nodes must list the
> > > +   SoC-specific version corresponding to the platform first
> > > +   followed by the generic version.
> > > +
> > > + - reg: the register base and size for the device registers
> > > + - interrupts: the interrupt for the device
> > > + - clocks: Reference to the parent clock
> > > +
> > > +The device node should contain two 'port' child nodes according to the
> > > +bindings defined in Documentation/devicetree/bindings/media/
> > > +video-interfaces.txt. Port 0 should connect the node that is the video
> > > +source for to the CSI-2. Port 1 should connect all the R-Car VIN
> > > +modules, which can make use of the CSI-2 module.
> > 
> > Should or shall?
> > 
> > I guess you could add that it is possible to leave them unconnected, too.
> 
> Which ports/endpoints are you talking about? In my mind it's not allowed 
> to leave them unconnected.
> 
> If there ever is a system with only 4 VIN instances (I'm not aware of 
> any such system) then yes the endpoints for those VIN not present in the 
> system in port 1 should be left unconnected but other then that they 
> should all be mandatory right? Or am I missing something?

I think so, yes. Then "shall" is right, isn't it?

> 
> > 
> > > +
> > > +- Port 0 - Video source
> > > +	- Reg 0 - sub-node describing the endpoint that is the video source
> > 
> > Which endpoint properties are mandatory for the receiver? Which ones are
> > optional? (I.e. it shouldn't be necessary to read driver code to write board
> > description.)
> 
> I will add a note that all endpoints in port 0 are mandatory and that 
> all endpoints that represents a connection to a VIN instance in the 
> system is mandatory for next version. Thanks I did not think about this 
> possibility.

Please list the mandatory and optional properties, too. Not just the
endpoints.

-- 
H�lsningar,

Sakari Ailus
e-mail: sakari.ailus@iki.fi	XMPP: sailus@retiisi.org.uk

Re: [PATCH v7 1/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver documentation

[Niklas Söderlund]

Hi Sakari,

On 2017-06-14 13:45:58 +0300, Sakari Ailus wrote:
> Hi Niklas,
> 
> On Tue, Jun 13, 2017 at 06:50:14PM +0200, Niklas Söderlund wrote:
> > Hi Sakari,
> > 
> > Thanks for your feedback.
> > 
> > On 2017-05-29 14:16:25 +0300, Sakari Ailus wrote:
> > > Hi Niklas,
> > > 
> > > On Wed, May 24, 2017 at 02:13:52AM +0200, Niklas Söderlund wrote:
> > > > From: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> > > > 
> > > > Documentation for Renesas R-Car MIPI CSI-2 receiver. The CSI-2 receivers
> > > > are located between the video sources (CSI-2 transmitters) and the video
> > > > grabbers (VIN) on Gen3 of Renesas R-Car SoC.
> > > > 
> > > > Each CSI-2 device is connected to more then one VIN device which
> > > > simultaneously can receive video from the same CSI-2 device. Each VIN
> > > > device can also be connected to more then one CSI-2 device. The routing
> > > > of which link are used are controlled by the VIN devices. There are only
> > > > a few possible routes which are set by hardware limitations, which are
> > > > different for each SoC in the Gen3 family.
> > > > 
> > > > To work with the limitations of routing possibilities it is necessary
> > > > for the DT bindings to describe which VIN device is connected to which
> > > > CSI-2 device. This is why port 1 needs to to assign reg numbers for each
> > > > VIN device that be connected to it. To setup and to know which links are
> > > > valid for each SoC is the responsibility of the VIN driver since the
> > > > register to configure it belongs to the VIN hardware.
> > > > 
> > > > Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> > > > ---
> > > >  .../devicetree/bindings/media/rcar-csi2.txt        | 116 +++++++++++++++++++++
> > > >  1 file changed, 116 insertions(+)
> > > >  create mode 100644 Documentation/devicetree/bindings/media/rcar-csi2.txt
> > > > 
> > > > diff --git a/Documentation/devicetree/bindings/media/rcar-csi2.txt b/Documentation/devicetree/bindings/media/rcar-csi2.txt
> > > > new file mode 100644
> > > > index 0000000000000000..f6e2027ee92b171a
> > > > --- /dev/null
> > > > +++ b/Documentation/devicetree/bindings/media/rcar-csi2.txt
> > > > @@ -0,0 +1,116 @@
> > > > +Renesas R-Car MIPI CSI-2
> > > > +------------------------
> > > > +
> > > > +The rcar-csi2 device provides MIPI CSI-2 capabilities for the Renesas R-Car
> > > > +family of devices. It is to be used in conjunction with the R-Car VIN module,
> > > > +which provides the video capture capabilities.
> > > > +
> > > > + - compatible: Must be one or more of the following
> > > > +   - "renesas,r8a7795-csi2" for the R8A7795 device.
> > > > +   - "renesas,r8a7796-csi2" for the R8A7796 device.
> > > > +   - "renesas,rcar-gen3-csi2" for a generic R-Car Gen3 compatible device.
> > > > +
> > > > +   When compatible with a generic version nodes must list the
> > > > +   SoC-specific version corresponding to the platform first
> > > > +   followed by the generic version.
> > > > +
> > > > + - reg: the register base and size for the device registers
> > > > + - interrupts: the interrupt for the device
> > > > + - clocks: Reference to the parent clock
> > > > +
> > > > +The device node should contain two 'port' child nodes according to the
> > > > +bindings defined in Documentation/devicetree/bindings/media/
> > > > +video-interfaces.txt. Port 0 should connect the node that is the video
> > > > +source for to the CSI-2. Port 1 should connect all the R-Car VIN
> > > > +modules, which can make use of the CSI-2 module.
> > > 
> > > Should or shall?
> > > 
> > > I guess you could add that it is possible to leave them unconnected, too.
> > 
> > Which ports/endpoints are you talking about? In my mind it's not allowed 
> > to leave them unconnected.
> > 
> > If there ever is a system with only 4 VIN instances (I'm not aware of 
> > any such system) then yes the endpoints for those VIN not present in the 
> > system in port 1 should be left unconnected but other then that they 
> > should all be mandatory right? Or am I missing something?
> 
> I think so, yes. Then "shall" is right, isn't it?

Yes shall is then the correct term, will update for next version.

> 
> > 
> > > 
> > > > +
> > > > +- Port 0 - Video source
> > > > +	- Reg 0 - sub-node describing the endpoint that is the video source
> > > 
> > > Which endpoint properties are mandatory for the receiver? Which ones are
> > > optional? (I.e. it shouldn't be necessary to read driver code to write board
> > > description.)
> > 
> > I will add a note that all endpoints in port 0 are mandatory and that 
> > all endpoints that represents a connection to a VIN instance in the 
> > system is mandatory for next version. Thanks I did not think about this 
> > possibility.
> 
> Please list the mandatory and optional properties, too. Not just the
> endpoints.

Good point, will do so.

> 
> -- 
> Hälsningar,
> 
> Sakari Ailus
> e-mail: sakari.ailus@iki.fi	XMPP: sailus@retiisi.org.uk

-- 
Regards,
Niklas Söderlund

Re: [PATCH v7 1/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver documentation

[Niklas Söderlund]

Hi Sakari,

On 2017-06-14 13:45:58 +0300, Sakari Ailus wrote:
> Hi Niklas,
> 
> On Tue, Jun 13, 2017 at 06:50:14PM +0200, Niklas S�derlund wrote:
> > Hi Sakari,
> > 
> > Thanks for your feedback.
> > 
> > On 2017-05-29 14:16:25 +0300, Sakari Ailus wrote:
> > > Hi Niklas,
> > > 
> > > On Wed, May 24, 2017 at 02:13:52AM +0200, Niklas S�derlund wrote:
> > > > From: Niklas S�derlund <niklas.soderlund+renesas@ragnatech.se>
> > > > 
> > > > Documentation for Renesas R-Car MIPI CSI-2 receiver. The CSI-2 receivers
> > > > are located between the video sources (CSI-2 transmitters) and the video
> > > > grabbers (VIN) on Gen3 of Renesas R-Car SoC.
> > > > 
> > > > Each CSI-2 device is connected to more then one VIN device which
> > > > simultaneously can receive video from the same CSI-2 device. Each VIN
> > > > device can also be connected to more then one CSI-2 device. The routing
> > > > of which link are used are controlled by the VIN devices. There are only
> > > > a few possible routes which are set by hardware limitations, which are
> > > > different for each SoC in the Gen3 family.
> > > > 
> > > > To work with the limitations of routing possibilities it is necessary
> > > > for the DT bindings to describe which VIN device is connected to which
> > > > CSI-2 device. This is why port 1 needs to to assign reg numbers for each
> > > > VIN device that be connected to it. To setup and to know which links are
> > > > valid for each SoC is the responsibility of the VIN driver since the
> > > > register to configure it belongs to the VIN hardware.
> > > > 
> > > > Signed-off-by: Niklas S�derlund <niklas.soderlund+renesas@ragnatech.se>
> > > > ---
> > > >  .../devicetree/bindings/media/rcar-csi2.txt        | 116 +++++++++++++++++++++
> > > >  1 file changed, 116 insertions(+)
> > > >  create mode 100644 Documentation/devicetree/bindings/media/rcar-csi2.txt
> > > > 
> > > > diff --git a/Documentation/devicetree/bindings/media/rcar-csi2.txt b/Documentation/devicetree/bindings/media/rcar-csi2.txt
> > > > new file mode 100644
> > > > index 0000000000000000..f6e2027ee92b171a
> > > > --- /dev/null
> > > > +++ b/Documentation/devicetree/bindings/media/rcar-csi2.txt
> > > > @@ -0,0 +1,116 @@
> > > > +Renesas R-Car MIPI CSI-2
> > > > +------------------------
> > > > +
> > > > +The rcar-csi2 device provides MIPI CSI-2 capabilities for the Renesas R-Car
> > > > +family of devices. It is to be used in conjunction with the R-Car VIN module,
> > > > +which provides the video capture capabilities.
> > > > +
> > > > + - compatible: Must be one or more of the following
> > > > +   - "renesas,r8a7795-csi2" for the R8A7795 device.
> > > > +   - "renesas,r8a7796-csi2" for the R8A7796 device.
> > > > +   - "renesas,rcar-gen3-csi2" for a generic R-Car Gen3 compatible device.
> > > > +
> > > > +   When compatible with a generic version nodes must list the
> > > > +   SoC-specific version corresponding to the platform first
> > > > +   followed by the generic version.
> > > > +
> > > > + - reg: the register base and size for the device registers
> > > > + - interrupts: the interrupt for the device
> > > > + - clocks: Reference to the parent clock
> > > > +
> > > > +The device node should contain two 'port' child nodes according to the
> > > > +bindings defined in Documentation/devicetree/bindings/media/
> > > > +video-interfaces.txt. Port 0 should connect the node that is the video
> > > > +source for to the CSI-2. Port 1 should connect all the R-Car VIN
> > > > +modules, which can make use of the CSI-2 module.
> > > 
> > > Should or shall?
> > > 
> > > I guess you could add that it is possible to leave them unconnected, too.
> > 
> > Which ports/endpoints are you talking about? In my mind it's not allowed 
> > to leave them unconnected.
> > 
> > If there ever is a system with only 4 VIN instances (I'm not aware of 
> > any such system) then yes the endpoints for those VIN not present in the 
> > system in port 1 should be left unconnected but other then that they 
> > should all be mandatory right? Or am I missing something?
> 
> I think so, yes. Then "shall" is right, isn't it?

Yes shall is then the correct term, will update for next version.

> 
> > 
> > > 
> > > > +
> > > > +- Port 0 - Video source
> > > > +	- Reg 0 - sub-node describing the endpoint that is the video source
> > > 
> > > Which endpoint properties are mandatory for the receiver? Which ones are
> > > optional? (I.e. it shouldn't be necessary to read driver code to write board
> > > description.)
> > 
> > I will add a note that all endpoints in port 0 are mandatory and that 
> > all endpoints that represents a connection to a VIN instance in the 
> > system is mandatory for next version. Thanks I did not think about this 
> > possibility.
> 
> Please list the mandatory and optional properties, too. Not just the
> endpoints.

Good point, will do so.

> 
> -- 
> H�lsningar,
> 
> Sakari Ailus
> e-mail: sakari.ailus@iki.fi	XMPP: sailus@retiisi.org.uk

-- 
Regards,
Niklas S�derlund

[PATCH v7 2/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver driver

[Niklas Söderlund]

From: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>

A V4L2 driver for Renesas R-Car MIPI CSI-2 receiver. The driver
supports the rcar-vin driver on R-Car Gen3 SoCs where separate CSI-2
hardware blocks are connected between the video sources and the video
grabbers (VIN).

Driver is based on a prototype by Koji Matsuoka in the Renesas BSP.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
---
 drivers/media/platform/rcar-vin/Kconfig     |  12 +
 drivers/media/platform/rcar-vin/Makefile    |   1 +
 drivers/media/platform/rcar-vin/rcar-csi2.c | 867 ++++++++++++++++++++++++++++
 3 files changed, 880 insertions(+)
 create mode 100644 drivers/media/platform/rcar-vin/rcar-csi2.c

diff --git a/drivers/media/platform/rcar-vin/Kconfig b/drivers/media/platform/rcar-vin/Kconfig
index af4c98b44d2e22cb..6875f30c1ae42631 100644
--- a/drivers/media/platform/rcar-vin/Kconfig
+++ b/drivers/media/platform/rcar-vin/Kconfig
@@ -1,3 +1,15 @@
+config VIDEO_RCAR_CSI2
+	tristate "R-Car MIPI CSI-2 Receiver"
+	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && OF
+	depends on ARCH_RENESAS || COMPILE_TEST
+	select V4L2_FWNODE
+	---help---
+	  Support for Renesas R-Car MIPI CSI-2 receiver.
+	  Supports R-Car Gen3 SoCs.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called rcar-csi2.
+
 config VIDEO_RCAR_VIN
 	tristate "R-Car Video Input (VIN) Driver"
 	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && OF && HAS_DMA && MEDIA_CONTROLLER
diff --git a/drivers/media/platform/rcar-vin/Makefile b/drivers/media/platform/rcar-vin/Makefile
index 48c5632c21dc060b..5ab803d3e7c1aa57 100644
--- a/drivers/media/platform/rcar-vin/Makefile
+++ b/drivers/media/platform/rcar-vin/Makefile
@@ -1,3 +1,4 @@
 rcar-vin-objs = rcar-core.o rcar-dma.o rcar-v4l2.o
 
+obj-$(CONFIG_VIDEO_RCAR_CSI2) += rcar-csi2.o
 obj-$(CONFIG_VIDEO_RCAR_VIN) += rcar-vin.o
diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
new file mode 100644
index 0000000000000000..1175f1fe4b139a13
--- /dev/null
+++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
@@ -0,0 +1,867 @@
+/*
+ * Driver for Renesas R-Car MIPI CSI-2 Receiver
+ *
+ * Copyright (C) 2017 Renesas Electronics Corp.
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_graph.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-fwnode.h>
+#include <media/v4l2-mc.h>
+#include <media/v4l2-subdev.h>
+
+/* Register offsets and bits */
+
+/* Control Timing Select */
+#define TREF_REG			0x00
+#define TREF_TREF			(1 << 0)
+
+/* Software Reset */
+#define SRST_REG			0x04
+#define SRST_SRST			(1 << 0)
+
+/* PHY Operation Control */
+#define PHYCNT_REG			0x08
+#define PHYCNT_SHUTDOWNZ		(1 << 17)
+#define PHYCNT_RSTZ			(1 << 16)
+#define PHYCNT_ENABLECLK		(1 << 4)
+#define PHYCNT_ENABLE_3			(1 << 3)
+#define PHYCNT_ENABLE_2			(1 << 2)
+#define PHYCNT_ENABLE_1			(1 << 1)
+#define PHYCNT_ENABLE_0			(1 << 0)
+
+/* Checksum Control */
+#define CHKSUM_REG			0x0c
+#define CHKSUM_ECC_EN			(1 << 1)
+#define CHKSUM_CRC_EN			(1 << 0)
+
+/*
+ * Channel Data Type Select
+ * VCDT[0-15]:  Channel 1 VCDT[16-31]:  Channel 2
+ * VCDT2[0-15]: Channel 3 VCDT2[16-31]: Channel 4
+ */
+#define VCDT_REG			0x10
+#define VCDT2_REG			0x14
+#define VCDT_VCDTN_EN			(1 << 15)
+#define VCDT_SEL_VC(n)			(((n) & 0x3) << 8)
+#define VCDT_SEL_DTN_ON			(1 << 6)
+#define VCDT_SEL_DT(n)			(((n) & 0x3f) << 0)
+
+/* Frame Data Type Select */
+#define FRDT_REG			0x18
+
+/* Field Detection Control */
+#define FLD_REG				0x1c
+#define FLD_FLD_NUM(n)			(((n) & 0xff) << 16)
+#define FLD_FLD_EN4			(1 << 3)
+#define FLD_FLD_EN3			(1 << 2)
+#define FLD_FLD_EN2			(1 << 1)
+#define FLD_FLD_EN			(1 << 0)
+
+/* Automatic Standby Control */
+#define ASTBY_REG			0x20
+
+/* Long Data Type Setting 0 */
+#define LNGDT0_REG			0x28
+
+/* Long Data Type Setting 1 */
+#define LNGDT1_REG			0x2c
+
+/* Interrupt Enable */
+#define INTEN_REG			0x30
+
+/* Interrupt Source Mask */
+#define INTCLOSE_REG			0x34
+
+/* Interrupt Status Monitor */
+#define INTSTATE_REG			0x38
+
+/* Interrupt Error Status Monitor */
+#define INTERRSTATE_REG			0x3c
+
+/* Short Packet Data */
+#define SHPDAT_REG			0x40
+
+/* Short Packet Count */
+#define SHPCNT_REG			0x44
+
+/* LINK Operation Control */
+#define LINKCNT_REG			0x48
+#define LINKCNT_MONITOR_EN		(1 << 31)
+#define LINKCNT_REG_MONI_PACT_EN	(1 << 25)
+#define LINKCNT_ICLK_NONSTOP		(1 << 24)
+
+/* Lane Swap */
+#define LSWAP_REG			0x4c
+#define LSWAP_L3SEL(n)			(((n) & 0x3) << 6)
+#define LSWAP_L2SEL(n)			(((n) & 0x3) << 4)
+#define LSWAP_L1SEL(n)			(((n) & 0x3) << 2)
+#define LSWAP_L0SEL(n)			(((n) & 0x3) << 0)
+
+/* PHY Test Interface Clear */
+#define PHTC_REG			0x58
+#define PHTC_TESTCLR			(1 << 0)
+
+/* PHY Frequency Control */
+#define PHYPLL_REG			0x68
+#define PHYPLL_HSFREQRANGE(n)		((n) << 16)
+
+struct phypll_hsfreqrange {
+	unsigned int	mbps;
+	unsigned char	reg;
+};
+
+static const struct phypll_hsfreqrange phypll_hsfreqrange_map[] = {
+	{ .mbps =   80,	.reg = 0x00 },
+	{ .mbps =   90,	.reg = 0x10 },
+	{ .mbps =  100,	.reg = 0x20 },
+	{ .mbps =  110,	.reg = 0x30 },
+	{ .mbps =  120,	.reg = 0x01 },
+	{ .mbps =  130,	.reg = 0x11 },
+	{ .mbps =  140,	.reg = 0x21 },
+	{ .mbps =  150,	.reg = 0x31 },
+	{ .mbps =  160,	.reg = 0x02 },
+	{ .mbps =  170,	.reg = 0x12 },
+	{ .mbps =  180,	.reg = 0x22 },
+	{ .mbps =  190,	.reg = 0x32 },
+	{ .mbps =  205,	.reg = 0x03 },
+	{ .mbps =  220,	.reg = 0x13 },
+	{ .mbps =  235,	.reg = 0x23 },
+	{ .mbps =  250,	.reg = 0x33 },
+	{ .mbps =  275,	.reg = 0x04 },
+	{ .mbps =  300,	.reg = 0x14 },
+	{ .mbps =  325,	.reg = 0x05 },
+	{ .mbps =  350,	.reg = 0x15 },
+	{ .mbps =  400,	.reg = 0x25 },
+	{ .mbps =  450,	.reg = 0x06 },
+	{ .mbps =  500,	.reg = 0x16 },
+	{ .mbps =  550,	.reg = 0x07 },
+	{ .mbps =  600,	.reg = 0x17 },
+	{ .mbps =  650,	.reg = 0x08 },
+	{ .mbps =  700,	.reg = 0x18 },
+	{ .mbps =  750,	.reg = 0x09 },
+	{ .mbps =  800,	.reg = 0x19 },
+	{ .mbps =  850,	.reg = 0x29 },
+	{ .mbps =  900,	.reg = 0x39 },
+	{ .mbps =  950,	.reg = 0x0A },
+	{ .mbps = 1000,	.reg = 0x1A },
+	{ .mbps = 1050,	.reg = 0x2A },
+	{ .mbps = 1100,	.reg = 0x3A },
+	{ .mbps = 1150,	.reg = 0x0B },
+	{ .mbps = 1200,	.reg = 0x1B },
+	{ .mbps = 1250,	.reg = 0x2B },
+	{ .mbps = 1300,	.reg = 0x3B },
+	{ .mbps = 1350,	.reg = 0x0C },
+	{ .mbps = 1400,	.reg = 0x1C },
+	{ .mbps = 1450,	.reg = 0x2C },
+	{ .mbps = 1500,	.reg = 0x3C },
+	/* guard */
+	{ .mbps =   0,	.reg = 0x00 },
+};
+
+/* PHY ESC Error Monitor */
+#define PHEERM_REG			0x74
+
+/* PHY Clock Lane Monitor */
+#define PHCLM_REG			0x78
+
+/* PHY Data Lane Monitor */
+#define PHDLM_REG			0x7c
+
+struct rcar_csi2_format {
+	unsigned int code;
+	unsigned int datatype;
+	unsigned int bpp;
+};
+
+static const struct rcar_csi2_format rcar_csi2_formats[] = {
+	{ .code = MEDIA_BUS_FMT_RGB888_1X24,	.datatype = 0x24, .bpp = 24},
+	{ .code = MEDIA_BUS_FMT_UYVY8_1X16,	.datatype = 0x1e, .bpp = 8 },
+	{ .code = MEDIA_BUS_FMT_UYVY8_2X8,	.datatype = 0x1e, .bpp = 8 },
+	{ .code = MEDIA_BUS_FMT_YUYV10_2X10,	.datatype = 0x1e, .bpp = 8 },
+};
+
+static const struct rcar_csi2_format *rcar_csi2_code_to_fmt(unsigned int code)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(rcar_csi2_formats); i++)
+		if (rcar_csi2_formats[i].code == code)
+			return rcar_csi2_formats + i;
+	return NULL;
+}
+
+enum rcar_csi2_pads {
+	RCAR_CSI2_SINK,
+	RCAR_CSI2_SOURCE_VC0,
+	RCAR_CSI2_SOURCE_VC1,
+	RCAR_CSI2_SOURCE_VC2,
+	RCAR_CSI2_SOURCE_VC3,
+	NR_OF_RCAR_CSI2_PAD,
+};
+
+struct rcar_csi2 {
+	struct device *dev;
+	void __iomem *base;
+
+	unsigned short lanes;
+	unsigned char lane_swap[4];
+
+	struct v4l2_subdev subdev;
+	struct media_pad pads[NR_OF_RCAR_CSI2_PAD];
+
+	struct v4l2_mbus_framefmt mf;
+
+	struct mutex lock;
+	int stream_count;
+
+	struct v4l2_async_notifier notifier;
+	struct {
+		struct v4l2_async_subdev asd;
+		struct v4l2_subdev *subdev;
+		struct fwnode_handle *fwnode;
+		unsigned int source_pad;
+	} remote;
+};
+
+static inline struct rcar_csi2 *sd_to_csi2(struct v4l2_subdev *sd)
+{
+	return container_of(sd, struct rcar_csi2, subdev);
+}
+
+static u32 rcar_csi2_read(struct rcar_csi2 *priv, unsigned int reg)
+{
+	return ioread32(priv->base + reg);
+}
+
+static void rcar_csi2_write(struct rcar_csi2 *priv, unsigned int reg, u32 data)
+{
+	iowrite32(data, priv->base + reg);
+}
+
+static void rcar_csi2_reset(struct rcar_csi2 *priv)
+{
+	rcar_csi2_write(priv, SRST_REG, SRST_SRST);
+	rcar_csi2_write(priv, SRST_REG, 0);
+}
+
+static int rcar_csi2_wait_phy_start(struct rcar_csi2 *priv)
+{
+	int timeout;
+
+	/* Wait for the clock and data lanes to enter LP-11 state. */
+	for (timeout = 100; timeout >= 0; timeout--) {
+		const u32 lane_mask = (1 << priv->lanes) - 1;
+
+		if ((rcar_csi2_read(priv, PHCLM_REG) & 1) == 1 &&
+		    (rcar_csi2_read(priv, PHDLM_REG) & lane_mask) == lane_mask)
+			return 0;
+
+		msleep(20);
+	}
+
+	dev_err(priv->dev, "Timeout waiting for LP-11 state\n");
+
+	return -ETIMEDOUT;
+}
+
+static int rcar_csi2_calc_phypll(struct rcar_csi2 *priv,
+				 struct v4l2_subdev *source,
+				 struct v4l2_mbus_framefmt *mf,
+				 u32 *phypll)
+{
+	const struct phypll_hsfreqrange *hsfreq;
+	const struct rcar_csi2_format *format;
+	struct v4l2_ext_controls ctrls;
+	struct v4l2_ext_control ctrl;
+	u64 mbps;
+	int ret;
+
+	memset(&ctrls, 0, sizeof(ctrls));
+	memset(&ctrl, 0, sizeof(ctrl));
+
+	ctrl.id = V4L2_CID_PIXEL_RATE;
+
+	ctrls.count = 1;
+	ctrls.controls = &ctrl;
+
+	ret = v4l2_g_ext_ctrls(source->ctrl_handler, &ctrls);
+	if (ret < 0) {
+		dev_err(priv->dev, "no link freq control in subdev %s\n",
+			source->name);
+		return ret;
+	}
+
+	format = rcar_csi2_code_to_fmt(mf->code);
+	if (!format) {
+		dev_err(priv->dev, "Unknown format: %d\n", mf->code);
+		return -EINVAL;
+	}
+
+	mbps = ctrl.value64 * format->bpp;
+	do_div(mbps, priv->lanes * 1000000);
+
+	for (hsfreq = phypll_hsfreqrange_map; hsfreq->mbps != 0; hsfreq++)
+		if (hsfreq->mbps >= mbps)
+			break;
+
+	if (!hsfreq->mbps) {
+		dev_err(priv->dev, "Unsupported PHY speed (%llu Mbps)", mbps);
+		return -ERANGE;
+	}
+
+	dev_dbg(priv->dev, "PHY HSFREQRANGE requested %llu got %u Mbps\n", mbps,
+		hsfreq->mbps);
+
+	*phypll = PHYPLL_HSFREQRANGE(hsfreq->reg);
+
+	return 0;
+}
+
+static int rcar_csi2_start(struct rcar_csi2 *priv)
+{
+	const struct rcar_csi2_format *format;
+	struct v4l2_subdev_format fmt;
+	struct media_pad *source_pad;
+	struct v4l2_subdev *source = NULL;
+	struct v4l2_mbus_framefmt *mf = &fmt.format;
+	u32 phycnt, phypll, tmp;
+	u32 vcdt = 0, vcdt2 = 0;
+	unsigned int i;
+	int ret;
+
+	source_pad =
+		media_entity_remote_pad(&priv->subdev.entity.pads[RCAR_CSI2_SINK]);
+	if (!source_pad) {
+		dev_err(priv->dev, "Could not find remote source pad\n");
+		return -ENODEV;
+	}
+
+	source = media_entity_to_v4l2_subdev(source_pad->entity);
+	if (!source) {
+		dev_err(priv->dev, "Could not find remote subdevice\n");
+		return -ENODEV;
+	}
+
+	dev_dbg(priv->dev, "Using source %s pad: %u\n", source->name,
+		source_pad->index);
+
+	fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
+	fmt.pad = source_pad->index;
+	ret = v4l2_subdev_call(source, pad, get_fmt, NULL, &fmt);
+	if (ret)
+		return ret;
+
+	dev_dbg(priv->dev, "Input size (%dx%d%c)\n", mf->width,
+		mf->height, mf->field == V4L2_FIELD_NONE ? 'p' : 'i');
+
+	/*
+	 * Enable all Virtual Channels
+	 *
+	 * NOTE: I'ts not possible to get individual format for each
+	 *       source virtual channel. Once this is possible in V4L2
+	 *       it should be used here.
+	 */
+	for (i = 0; i < 4; i++) {
+
+		format = rcar_csi2_code_to_fmt(mf->code);
+		if (!format) {
+			dev_err(priv->dev, "Unsupported media bus format: %d\n",
+				mf->code);
+			return -EINVAL;
+		}
+
+		tmp = VCDT_SEL_VC(i) | VCDT_VCDTN_EN | VCDT_SEL_DTN_ON |
+			VCDT_SEL_DT(format->datatype);
+
+		/* Store in correct reg and offset */
+		if (i < 2)
+			vcdt |= tmp << ((i % 2) * 16);
+		else
+			vcdt2 |= tmp << ((i % 2) * 16);
+	}
+
+	switch (priv->lanes) {
+	case 1:
+		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_0;
+		break;
+	case 2:
+		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_1 | PHYCNT_ENABLE_0;
+		break;
+	case 4:
+		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_3 | PHYCNT_ENABLE_2 |
+			PHYCNT_ENABLE_1 | PHYCNT_ENABLE_0;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	ret = rcar_csi2_calc_phypll(priv, source, mf, &phypll);
+	if (ret)
+		return ret;
+
+	/* Init */
+	rcar_csi2_write(priv, TREF_REG, TREF_TREF);
+	rcar_csi2_reset(priv);
+	rcar_csi2_write(priv, PHTC_REG, 0);
+
+	/* Configure */
+	rcar_csi2_write(priv, FLD_REG, FLD_FLD_NUM(2) | FLD_FLD_EN4 |
+			FLD_FLD_EN3 | FLD_FLD_EN2 | FLD_FLD_EN);
+	rcar_csi2_write(priv, VCDT_REG, vcdt);
+	rcar_csi2_write(priv, VCDT2_REG, vcdt2);
+	/* Lanes are zero indexed */
+	rcar_csi2_write(priv, LSWAP_REG,
+			LSWAP_L0SEL(priv->lane_swap[0] - 1) |
+			LSWAP_L1SEL(priv->lane_swap[1] - 1) |
+			LSWAP_L2SEL(priv->lane_swap[2] - 1) |
+			LSWAP_L3SEL(priv->lane_swap[3] - 1));
+
+	/* Start */
+	rcar_csi2_write(priv, PHYPLL_REG, phypll);
+	rcar_csi2_write(priv, PHYCNT_REG, phycnt);
+	rcar_csi2_write(priv, LINKCNT_REG, LINKCNT_MONITOR_EN |
+			LINKCNT_REG_MONI_PACT_EN | LINKCNT_ICLK_NONSTOP);
+	rcar_csi2_write(priv, PHYCNT_REG, phycnt | PHYCNT_SHUTDOWNZ);
+	rcar_csi2_write(priv, PHYCNT_REG, phycnt | PHYCNT_SHUTDOWNZ |
+			PHYCNT_RSTZ);
+
+	return rcar_csi2_wait_phy_start(priv);
+}
+
+static void rcar_csi2_stop(struct rcar_csi2 *priv)
+{
+	rcar_csi2_write(priv, PHYCNT_REG, 0);
+
+	rcar_csi2_reset(priv);
+}
+
+static int rcar_csi2_sd_info(struct rcar_csi2 *priv, struct v4l2_subdev **sd)
+{
+	struct media_pad *pad;
+
+	pad = media_entity_remote_pad(&priv->pads[RCAR_CSI2_SINK]);
+	if (!pad) {
+		dev_err(priv->dev, "Could not find remote pad\n");
+		return -ENODEV;
+	}
+
+	*sd = media_entity_to_v4l2_subdev(pad->entity);
+	if (!*sd) {
+		dev_err(priv->dev, "Could not find remote subdevice\n");
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static int rcar_csi2_s_stream(struct v4l2_subdev *sd, int enable)
+{
+	struct rcar_csi2 *priv = sd_to_csi2(sd);
+	struct v4l2_subdev *nextsd;
+	int ret;
+
+	mutex_lock(&priv->lock);
+
+	ret = rcar_csi2_sd_info(priv, &nextsd);
+	if (ret)
+		goto out;
+
+	priv->stream_count += enable ? 1 : -1;
+
+	if (enable && priv->stream_count == 1) {
+		ret =  rcar_csi2_start(priv);
+		if (ret)
+			goto out;
+		ret = v4l2_subdev_call(nextsd, video, s_stream, 1);
+
+	} else if (!enable && !priv->stream_count) {
+		rcar_csi2_stop(priv);
+		ret = v4l2_subdev_call(nextsd, video, s_stream, 0);
+	}
+out:
+	mutex_unlock(&priv->lock);
+
+	return ret;
+}
+
+static int rcar_csi2_s_power(struct v4l2_subdev *sd, int on)
+{
+	struct rcar_csi2 *priv = sd_to_csi2(sd);
+
+	if (on)
+		pm_runtime_get_sync(priv->dev);
+	else
+		pm_runtime_put(priv->dev);
+
+	return 0;
+}
+
+static int rcar_csi2_set_pad_format(struct v4l2_subdev *sd,
+				    struct v4l2_subdev_pad_config *cfg,
+				    struct v4l2_subdev_format *format)
+{
+	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
+
+	if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE)
+		priv->mf = format->format;
+
+	return 0;
+}
+
+static int rcar_csi2_get_pad_format(struct v4l2_subdev *sd,
+				    struct v4l2_subdev_pad_config *cfg,
+				    struct v4l2_subdev_format *format)
+{
+	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
+
+	format->format = priv->mf;
+
+	return 0;
+}
+
+static const struct v4l2_subdev_video_ops rcar_csi2_video_ops = {
+	.s_stream = rcar_csi2_s_stream,
+};
+
+static const struct v4l2_subdev_core_ops rcar_csi2_subdev_core_ops = {
+	.s_power = rcar_csi2_s_power,
+};
+
+static const struct v4l2_subdev_pad_ops rcar_csi2_pad_ops = {
+	.set_fmt = rcar_csi2_set_pad_format,
+	.get_fmt = rcar_csi2_get_pad_format,
+};
+
+static const struct v4l2_subdev_ops rcar_csi2_subdev_ops = {
+	.video	= &rcar_csi2_video_ops,
+	.core	= &rcar_csi2_subdev_core_ops,
+	.pad	= &rcar_csi2_pad_ops,
+};
+
+/* -----------------------------------------------------------------------------
+ * Async and registered of subdevices and links
+ */
+
+#define notifier_to_priv(n) container_of(n, struct rcar_csi2, notifier)
+
+static int rcar_csi2_notify_complete(struct v4l2_async_notifier *notifier)
+{
+	struct rcar_csi2 *priv = notifier_to_priv(notifier);
+	int ret;
+
+	ret = v4l2_device_register_subdev_nodes(priv->subdev.v4l2_dev);
+	if (ret) {
+		dev_err(priv->dev, "Failed to register subdev nodes\n");
+		return ret;
+	}
+
+	return media_create_pad_link(&priv->remote.subdev->entity,
+				     priv->remote.source_pad,
+				     &priv->subdev.entity, 0,
+				     MEDIA_LNK_FL_ENABLED |
+				     MEDIA_LNK_FL_IMMUTABLE);
+}
+
+static int rcar_csi2_notify_bound(struct v4l2_async_notifier *notifier,
+				   struct v4l2_subdev *subdev,
+				   struct v4l2_async_subdev *asd)
+{
+	struct rcar_csi2 *priv = notifier_to_priv(notifier);
+	int ret;
+
+	v4l2_set_subdev_hostdata(subdev, priv);
+
+	ret = media_entity_pad_from_fwnode(&subdev->entity,
+					   priv->remote.fwnode,
+					   MEDIA_PAD_FL_SOURCE,
+					   &priv->remote.source_pad);
+	if (ret) {
+		dev_err(priv->dev, "Failed to find pad for %s\n",
+			subdev->name);
+		return ret;
+	}
+
+	dev_dbg(priv->dev, "Bound %s pad: %d\n", subdev->name,
+		priv->remote.source_pad);
+	priv->remote.subdev = subdev;
+
+	return 0;
+}
+static void rcar_csi2_notify_unbind(struct v4l2_async_notifier *notifier,
+				     struct v4l2_subdev *subdev,
+				     struct v4l2_async_subdev *asd)
+{
+	struct rcar_csi2 *priv = notifier_to_priv(notifier);
+
+	dev_dbg(priv->dev, "Unbind %s\n", subdev->name);
+	priv->remote.subdev = NULL;
+}
+
+static int rcar_csi2_registered(struct v4l2_subdev *sd)
+{
+	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
+	struct v4l2_async_subdev **subdevs = NULL;
+	int ret;
+
+	subdevs = devm_kzalloc(priv->dev, sizeof(*subdevs), GFP_KERNEL);
+	if (subdevs == NULL)
+		return -ENOMEM;
+
+	subdevs[0] = &priv->remote.asd;
+
+	priv->notifier.num_subdevs = 1;
+	priv->notifier.subdevs = subdevs;
+	priv->notifier.bound = rcar_csi2_notify_bound;
+	priv->notifier.unbind = rcar_csi2_notify_unbind;
+	priv->notifier.complete = rcar_csi2_notify_complete;
+
+	ret = v4l2_async_subnotifier_register(&priv->subdev, &priv->notifier);
+	if (ret < 0) {
+		dev_err(priv->dev, "Notifier registration failed\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static void rcar_csi2_unregistered(struct v4l2_subdev *sd)
+{
+	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
+
+	v4l2_async_subnotifier_unregister(&priv->notifier);
+}
+
+static const struct v4l2_subdev_internal_ops rcar_csi2_internal_ops = {
+	.registered = rcar_csi2_registered,
+	.unregistered = rcar_csi2_unregistered,
+};
+
+static int rcar_csi2_parse_dt_subdevice(struct rcar_csi2 *priv)
+{
+	struct device_node *remote, *ep;
+	struct v4l2_fwnode_endpoint v4l2_ep;
+	int ret;
+
+	ep = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0);
+	if (!ep) {
+		dev_err(priv->dev, "Not connected to subdevice\n");
+		return -EINVAL;
+	}
+
+	ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &v4l2_ep);
+	if (ret) {
+		dev_err(priv->dev, "Could not parse v4l2 endpoint\n");
+		of_node_put(ep);
+		return -EINVAL;
+	}
+
+	if (v4l2_ep.bus_type != V4L2_MBUS_CSI2) {
+		dev_err(priv->dev, "Unknown media bus type: 0x%x\n",
+			v4l2_ep.bus_type);
+		of_node_put(ep);
+		return -EINVAL;
+	}
+
+	priv->remote.fwnode =
+		fwnode_graph_get_remote_endpoint(of_fwnode_handle(ep));
+
+	remote = of_graph_get_remote_port_parent(ep);
+	of_node_put(ep);
+	if (!remote) {
+		dev_err(priv->dev, "No subdevice found for endpoint '%s'\n",
+			of_node_full_name(ep));
+		return -EINVAL;
+	}
+
+	priv->remote.asd.match.fwnode.fwnode = of_fwnode_handle(remote);
+	priv->remote.asd.match_type = V4L2_ASYNC_MATCH_FWNODE;
+
+	dev_dbg(priv->dev, "Found '%s'\n", of_node_full_name(remote));
+
+	return 0;
+}
+
+/* -----------------------------------------------------------------------------
+ * Platform Device Driver
+ */
+
+static const struct of_device_id rcar_csi2_of_table[] = {
+	{ .compatible = "renesas,rcar-gen3-csi2" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, rcar_csi2_of_table);
+
+static const struct media_entity_operations rcar_csi2_entity_ops = {
+	.link_validate = v4l2_subdev_link_validate,
+};
+
+static int rcar_csi2_parse_dt_settings(struct rcar_csi2 *priv)
+{
+	struct v4l2_fwnode_endpoint v4l2_ep;
+	struct device_node *ep;
+	unsigned int i;
+	int ret;
+
+	ep = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0);
+	if (!ep)
+		return -EINVAL;
+
+	ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &v4l2_ep);
+	of_node_put(ep);
+	if (ret) {
+		dev_err(priv->dev, "Could not parse v4l2 endpoint\n");
+		return -EINVAL;
+	}
+
+	if (v4l2_ep.bus_type != V4L2_MBUS_CSI2) {
+		dev_err(priv->dev, "Unsupported media bus type for %s\n",
+			of_node_full_name(ep));
+		return -EINVAL;
+	}
+
+	priv->lanes = v4l2_ep.bus.mipi_csi2.num_data_lanes;
+	if (priv->lanes != 1 && priv->lanes != 2 && priv->lanes != 4) {
+		dev_err(priv->dev, "Unsupported number of data-lanes: %d\n",
+			priv->lanes);
+		return -EINVAL;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(priv->lane_swap); i++) {
+		priv->lane_swap[i] = i < priv->lanes ?
+			v4l2_ep.bus.mipi_csi2.data_lanes[i] : i;
+
+		/* Check for valid lane number */
+		if (priv->lane_swap[i] < 1 || priv->lane_swap[i] > 4) {
+			dev_err(priv->dev, "data-lanes must be in 1-4 range\n");
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+static int rcar_csi2_probe_resources(struct rcar_csi2 *priv,
+				     struct platform_device *pdev)
+{
+	struct resource *mem;
+	int irq;
+
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!mem)
+		return -ENODEV;
+
+	priv->base = devm_ioremap_resource(&pdev->dev, mem);
+	if (IS_ERR(priv->base))
+		return PTR_ERR(priv->base);
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return irq;
+
+	return 0;
+}
+
+static int rcar_csi2_probe(struct platform_device *pdev)
+{
+	struct rcar_csi2 *priv;
+	unsigned int i;
+	int ret;
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->dev = &pdev->dev;
+
+	mutex_init(&priv->lock);
+	priv->stream_count = 0;
+
+	ret = rcar_csi2_parse_dt_settings(priv);
+	if (ret)
+		return ret;
+
+	ret = rcar_csi2_parse_dt_subdevice(priv);
+	if (ret)
+		return ret;
+
+	ret = rcar_csi2_probe_resources(priv, pdev);
+	if (ret) {
+		dev_err(priv->dev, "Failed to get resources\n");
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, priv);
+
+	priv->subdev.owner = THIS_MODULE;
+	priv->subdev.dev = &pdev->dev;
+	v4l2_subdev_init(&priv->subdev, &rcar_csi2_subdev_ops);
+	v4l2_set_subdevdata(&priv->subdev, &pdev->dev);
+	snprintf(priv->subdev.name, V4L2_SUBDEV_NAME_SIZE, "%s %s",
+		 KBUILD_MODNAME, dev_name(&pdev->dev));
+	priv->subdev.flags = V4L2_SUBDEV_FL_HAS_DEVNODE;
+	priv->subdev.internal_ops = &rcar_csi2_internal_ops;
+
+	priv->subdev.entity.function = MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER;
+	priv->subdev.entity.ops = &rcar_csi2_entity_ops;
+
+	priv->pads[RCAR_CSI2_SINK].flags = MEDIA_PAD_FL_SINK;
+	for (i = RCAR_CSI2_SOURCE_VC0; i < NR_OF_RCAR_CSI2_PAD; i++)
+		priv->pads[i].flags = MEDIA_PAD_FL_SOURCE;
+
+	ret = media_entity_pads_init(&priv->subdev.entity, NR_OF_RCAR_CSI2_PAD,
+				     priv->pads);
+	if (ret)
+		return ret;
+
+	ret = v4l2_async_register_subdev(&priv->subdev);
+	if (ret < 0)
+		return ret;
+
+	pm_runtime_enable(&pdev->dev);
+
+	dev_info(priv->dev, "%d lanes found\n", priv->lanes);
+
+	return 0;
+}
+
+static int rcar_csi2_remove(struct platform_device *pdev)
+{
+	struct rcar_csi2 *priv = platform_get_drvdata(pdev);
+
+	v4l2_async_unregister_subdev(&priv->subdev);
+
+	pm_runtime_disable(&pdev->dev);
+
+	return 0;
+}
+
+static struct platform_driver __refdata rcar_csi2_pdrv = {
+	.remove	= rcar_csi2_remove,
+	.probe	= rcar_csi2_probe,
+	.driver	= {
+		.name	= "rcar-csi2",
+		.of_match_table	= of_match_ptr(rcar_csi2_of_table),
+	},
+};
+
+module_platform_driver(rcar_csi2_pdrv);
+
+MODULE_AUTHOR("Niklas Söderlund <niklas.soderlund@ragnatech.se>");
+MODULE_DESCRIPTION("Renesas R-Car MIPI CSI-2 receiver");
+MODULE_LICENSE("GPL v2");
-- 
2.13.0

Re: [PATCH v7 2/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver driver

[Hans Verkuil]

On 05/24/2017 02:13 AM, Niklas Söderlund wrote:
> From: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> 
> A V4L2 driver for Renesas R-Car MIPI CSI-2 receiver. The driver
> supports the rcar-vin driver on R-Car Gen3 SoCs where separate CSI-2
> hardware blocks are connected between the video sources and the video
> grabbers (VIN).
> 
> Driver is based on a prototype by Koji Matsuoka in the Renesas BSP.
> 
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> ---
>   drivers/media/platform/rcar-vin/Kconfig     |  12 +
>   drivers/media/platform/rcar-vin/Makefile    |   1 +
>   drivers/media/platform/rcar-vin/rcar-csi2.c | 867 ++++++++++++++++++++++++++++
>   3 files changed, 880 insertions(+)
>   create mode 100644 drivers/media/platform/rcar-vin/rcar-csi2.c
> 
> diff --git a/drivers/media/platform/rcar-vin/Kconfig b/drivers/media/platform/rcar-vin/Kconfig
> index af4c98b44d2e22cb..6875f30c1ae42631 100644
> --- a/drivers/media/platform/rcar-vin/Kconfig
> +++ b/drivers/media/platform/rcar-vin/Kconfig
> @@ -1,3 +1,15 @@
> +config VIDEO_RCAR_CSI2
> +	tristate "R-Car MIPI CSI-2 Receiver"
> +	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && OF
> +	depends on ARCH_RENESAS || COMPILE_TEST
> +	select V4L2_FWNODE
> +	---help---
> +	  Support for Renesas R-Car MIPI CSI-2 receiver.
> +	  Supports R-Car Gen3 SoCs.
> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called rcar-csi2.
> +
>   config VIDEO_RCAR_VIN
>   	tristate "R-Car Video Input (VIN) Driver"
>   	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && OF && HAS_DMA && MEDIA_CONTROLLER
> diff --git a/drivers/media/platform/rcar-vin/Makefile b/drivers/media/platform/rcar-vin/Makefile
> index 48c5632c21dc060b..5ab803d3e7c1aa57 100644
> --- a/drivers/media/platform/rcar-vin/Makefile
> +++ b/drivers/media/platform/rcar-vin/Makefile
> @@ -1,3 +1,4 @@
>   rcar-vin-objs = rcar-core.o rcar-dma.o rcar-v4l2.o
>   
> +obj-$(CONFIG_VIDEO_RCAR_CSI2) += rcar-csi2.o
>   obj-$(CONFIG_VIDEO_RCAR_VIN) += rcar-vin.o
> diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
> new file mode 100644
> index 0000000000000000..1175f1fe4b139a13
> --- /dev/null
> +++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
> @@ -0,0 +1,867 @@
> +/*
> + * Driver for Renesas R-Car MIPI CSI-2 Receiver
> + *
> + * Copyright (C) 2017 Renesas Electronics Corp.
> + *
> + * This program is free software; you can redistribute  it and/or modify it
> + * under  the terms of  the GNU General  Public License as published by the
> + * Free Software Foundation;  either version 2 of the  License, or (at your
> + * option) any later version.
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/of_graph.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +
> +#include <media/v4l2-ctrls.h>
> +#include <media/v4l2-device.h>
> +#include <media/v4l2-fwnode.h>
> +#include <media/v4l2-mc.h>
> +#include <media/v4l2-subdev.h>
> +
> +/* Register offsets and bits */
> +
> +/* Control Timing Select */
> +#define TREF_REG			0x00
> +#define TREF_TREF			(1 << 0)
> +
> +/* Software Reset */
> +#define SRST_REG			0x04
> +#define SRST_SRST			(1 << 0)
> +
> +/* PHY Operation Control */
> +#define PHYCNT_REG			0x08
> +#define PHYCNT_SHUTDOWNZ		(1 << 17)
> +#define PHYCNT_RSTZ			(1 << 16)
> +#define PHYCNT_ENABLECLK		(1 << 4)
> +#define PHYCNT_ENABLE_3			(1 << 3)
> +#define PHYCNT_ENABLE_2			(1 << 2)
> +#define PHYCNT_ENABLE_1			(1 << 1)
> +#define PHYCNT_ENABLE_0			(1 << 0)
> +
> +/* Checksum Control */
> +#define CHKSUM_REG			0x0c
> +#define CHKSUM_ECC_EN			(1 << 1)
> +#define CHKSUM_CRC_EN			(1 << 0)
> +
> +/*
> + * Channel Data Type Select
> + * VCDT[0-15]:  Channel 1 VCDT[16-31]:  Channel 2
> + * VCDT2[0-15]: Channel 3 VCDT2[16-31]: Channel 4
> + */
> +#define VCDT_REG			0x10
> +#define VCDT2_REG			0x14
> +#define VCDT_VCDTN_EN			(1 << 15)
> +#define VCDT_SEL_VC(n)			(((n) & 0x3) << 8)
> +#define VCDT_SEL_DTN_ON			(1 << 6)
> +#define VCDT_SEL_DT(n)			(((n) & 0x3f) << 0)
> +
> +/* Frame Data Type Select */
> +#define FRDT_REG			0x18
> +
> +/* Field Detection Control */
> +#define FLD_REG				0x1c
> +#define FLD_FLD_NUM(n)			(((n) & 0xff) << 16)
> +#define FLD_FLD_EN4			(1 << 3)
> +#define FLD_FLD_EN3			(1 << 2)
> +#define FLD_FLD_EN2			(1 << 1)
> +#define FLD_FLD_EN			(1 << 0)
> +
> +/* Automatic Standby Control */
> +#define ASTBY_REG			0x20
> +
> +/* Long Data Type Setting 0 */
> +#define LNGDT0_REG			0x28
> +
> +/* Long Data Type Setting 1 */
> +#define LNGDT1_REG			0x2c
> +
> +/* Interrupt Enable */
> +#define INTEN_REG			0x30
> +
> +/* Interrupt Source Mask */
> +#define INTCLOSE_REG			0x34
> +
> +/* Interrupt Status Monitor */
> +#define INTSTATE_REG			0x38
> +
> +/* Interrupt Error Status Monitor */
> +#define INTERRSTATE_REG			0x3c
> +
> +/* Short Packet Data */
> +#define SHPDAT_REG			0x40
> +
> +/* Short Packet Count */
> +#define SHPCNT_REG			0x44
> +
> +/* LINK Operation Control */
> +#define LINKCNT_REG			0x48
> +#define LINKCNT_MONITOR_EN		(1 << 31)
> +#define LINKCNT_REG_MONI_PACT_EN	(1 << 25)
> +#define LINKCNT_ICLK_NONSTOP		(1 << 24)
> +
> +/* Lane Swap */
> +#define LSWAP_REG			0x4c
> +#define LSWAP_L3SEL(n)			(((n) & 0x3) << 6)
> +#define LSWAP_L2SEL(n)			(((n) & 0x3) << 4)
> +#define LSWAP_L1SEL(n)			(((n) & 0x3) << 2)
> +#define LSWAP_L0SEL(n)			(((n) & 0x3) << 0)
> +
> +/* PHY Test Interface Clear */
> +#define PHTC_REG			0x58
> +#define PHTC_TESTCLR			(1 << 0)
> +
> +/* PHY Frequency Control */
> +#define PHYPLL_REG			0x68
> +#define PHYPLL_HSFREQRANGE(n)		((n) << 16)
> +
> +struct phypll_hsfreqrange {
> +	unsigned int	mbps;
> +	unsigned char	reg;
> +};
> +
> +static const struct phypll_hsfreqrange phypll_hsfreqrange_map[] = {
> +	{ .mbps =   80,	.reg = 0x00 },
> +	{ .mbps =   90,	.reg = 0x10 },
> +	{ .mbps =  100,	.reg = 0x20 },
> +	{ .mbps =  110,	.reg = 0x30 },
> +	{ .mbps =  120,	.reg = 0x01 },
> +	{ .mbps =  130,	.reg = 0x11 },
> +	{ .mbps =  140,	.reg = 0x21 },
> +	{ .mbps =  150,	.reg = 0x31 },
> +	{ .mbps =  160,	.reg = 0x02 },
> +	{ .mbps =  170,	.reg = 0x12 },
> +	{ .mbps =  180,	.reg = 0x22 },
> +	{ .mbps =  190,	.reg = 0x32 },
> +	{ .mbps =  205,	.reg = 0x03 },
> +	{ .mbps =  220,	.reg = 0x13 },
> +	{ .mbps =  235,	.reg = 0x23 },
> +	{ .mbps =  250,	.reg = 0x33 },
> +	{ .mbps =  275,	.reg = 0x04 },
> +	{ .mbps =  300,	.reg = 0x14 },
> +	{ .mbps =  325,	.reg = 0x05 },
> +	{ .mbps =  350,	.reg = 0x15 },
> +	{ .mbps =  400,	.reg = 0x25 },
> +	{ .mbps =  450,	.reg = 0x06 },
> +	{ .mbps =  500,	.reg = 0x16 },
> +	{ .mbps =  550,	.reg = 0x07 },
> +	{ .mbps =  600,	.reg = 0x17 },
> +	{ .mbps =  650,	.reg = 0x08 },
> +	{ .mbps =  700,	.reg = 0x18 },
> +	{ .mbps =  750,	.reg = 0x09 },
> +	{ .mbps =  800,	.reg = 0x19 },
> +	{ .mbps =  850,	.reg = 0x29 },
> +	{ .mbps =  900,	.reg = 0x39 },
> +	{ .mbps =  950,	.reg = 0x0A },
> +	{ .mbps = 1000,	.reg = 0x1A },
> +	{ .mbps = 1050,	.reg = 0x2A },
> +	{ .mbps = 1100,	.reg = 0x3A },
> +	{ .mbps = 1150,	.reg = 0x0B },
> +	{ .mbps = 1200,	.reg = 0x1B },
> +	{ .mbps = 1250,	.reg = 0x2B },
> +	{ .mbps = 1300,	.reg = 0x3B },
> +	{ .mbps = 1350,	.reg = 0x0C },
> +	{ .mbps = 1400,	.reg = 0x1C },
> +	{ .mbps = 1450,	.reg = 0x2C },
> +	{ .mbps = 1500,	.reg = 0x3C },
> +	/* guard */
> +	{ .mbps =   0,	.reg = 0x00 },
> +};
> +
> +/* PHY ESC Error Monitor */
> +#define PHEERM_REG			0x74
> +
> +/* PHY Clock Lane Monitor */
> +#define PHCLM_REG			0x78
> +
> +/* PHY Data Lane Monitor */
> +#define PHDLM_REG			0x7c
> +
> +struct rcar_csi2_format {
> +	unsigned int code;
> +	unsigned int datatype;
> +	unsigned int bpp;
> +};
> +
> +static const struct rcar_csi2_format rcar_csi2_formats[] = {
> +	{ .code = MEDIA_BUS_FMT_RGB888_1X24,	.datatype = 0x24, .bpp = 24},
> +	{ .code = MEDIA_BUS_FMT_UYVY8_1X16,	.datatype = 0x1e, .bpp = 8 },
> +	{ .code = MEDIA_BUS_FMT_UYVY8_2X8,	.datatype = 0x1e, .bpp = 8 },
> +	{ .code = MEDIA_BUS_FMT_YUYV10_2X10,	.datatype = 0x1e, .bpp = 8 },
> +};
> +
> +static const struct rcar_csi2_format *rcar_csi2_code_to_fmt(unsigned int code)
> +{
> +	int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(rcar_csi2_formats); i++)
> +		if (rcar_csi2_formats[i].code == code)
> +			return rcar_csi2_formats + i;
> +	return NULL;
> +}
> +
> +enum rcar_csi2_pads {
> +	RCAR_CSI2_SINK,
> +	RCAR_CSI2_SOURCE_VC0,
> +	RCAR_CSI2_SOURCE_VC1,
> +	RCAR_CSI2_SOURCE_VC2,
> +	RCAR_CSI2_SOURCE_VC3,
> +	NR_OF_RCAR_CSI2_PAD,
> +};
> +
> +struct rcar_csi2 {
> +	struct device *dev;
> +	void __iomem *base;
> +
> +	unsigned short lanes;
> +	unsigned char lane_swap[4];
> +
> +	struct v4l2_subdev subdev;
> +	struct media_pad pads[NR_OF_RCAR_CSI2_PAD];
> +
> +	struct v4l2_mbus_framefmt mf;
> +
> +	struct mutex lock;
> +	int stream_count;
> +
> +	struct v4l2_async_notifier notifier;
> +	struct {
> +		struct v4l2_async_subdev asd;
> +		struct v4l2_subdev *subdev;
> +		struct fwnode_handle *fwnode;
> +		unsigned int source_pad;
> +	} remote;
> +};
> +
> +static inline struct rcar_csi2 *sd_to_csi2(struct v4l2_subdev *sd)
> +{
> +	return container_of(sd, struct rcar_csi2, subdev);
> +}
> +
> +static u32 rcar_csi2_read(struct rcar_csi2 *priv, unsigned int reg)
> +{
> +	return ioread32(priv->base + reg);
> +}
> +
> +static void rcar_csi2_write(struct rcar_csi2 *priv, unsigned int reg, u32 data)
> +{
> +	iowrite32(data, priv->base + reg);
> +}
> +
> +static void rcar_csi2_reset(struct rcar_csi2 *priv)
> +{
> +	rcar_csi2_write(priv, SRST_REG, SRST_SRST);
> +	rcar_csi2_write(priv, SRST_REG, 0);
> +}
> +
> +static int rcar_csi2_wait_phy_start(struct rcar_csi2 *priv)
> +{
> +	int timeout;
> +
> +	/* Wait for the clock and data lanes to enter LP-11 state. */
> +	for (timeout = 100; timeout >= 0; timeout--) {
> +		const u32 lane_mask = (1 << priv->lanes) - 1;
> +
> +		if ((rcar_csi2_read(priv, PHCLM_REG) & 1) == 1 &&
> +		    (rcar_csi2_read(priv, PHDLM_REG) & lane_mask) == lane_mask)
> +			return 0;
> +
> +		msleep(20);
> +	}
> +
> +	dev_err(priv->dev, "Timeout waiting for LP-11 state\n");
> +
> +	return -ETIMEDOUT;
> +}
> +
> +static int rcar_csi2_calc_phypll(struct rcar_csi2 *priv,
> +				 struct v4l2_subdev *source,
> +				 struct v4l2_mbus_framefmt *mf,
> +				 u32 *phypll)
> +{
> +	const struct phypll_hsfreqrange *hsfreq;
> +	const struct rcar_csi2_format *format;
> +	struct v4l2_ext_controls ctrls;
> +	struct v4l2_ext_control ctrl;
> +	u64 mbps;
> +	int ret;
> +
> +	memset(&ctrls, 0, sizeof(ctrls));
> +	memset(&ctrl, 0, sizeof(ctrl));
> +
> +	ctrl.id = V4L2_CID_PIXEL_RATE;
> +
> +	ctrls.count = 1;
> +	ctrls.controls = &ctrl;
> +
> +	ret = v4l2_g_ext_ctrls(source->ctrl_handler, &ctrls);
> +	if (ret < 0) {
> +		dev_err(priv->dev, "no link freq control in subdev %s\n",
> +			source->name);
> +		return ret;
> +	}

Please use v4l2_ctrl_g_ctrl_int64 instead. v4l2_g_ext_ctrls is not intended to
be used by drivers.

> +
> +	format = rcar_csi2_code_to_fmt(mf->code);
> +	if (!format) {
> +		dev_err(priv->dev, "Unknown format: %d\n", mf->code);
> +		return -EINVAL;
> +	}
> +
> +	mbps = ctrl.value64 * format->bpp;
> +	do_div(mbps, priv->lanes * 1000000);
> +
> +	for (hsfreq = phypll_hsfreqrange_map; hsfreq->mbps != 0; hsfreq++)
> +		if (hsfreq->mbps >= mbps)
> +			break;
> +
> +	if (!hsfreq->mbps) {
> +		dev_err(priv->dev, "Unsupported PHY speed (%llu Mbps)", mbps);
> +		return -ERANGE;
> +	}
> +
> +	dev_dbg(priv->dev, "PHY HSFREQRANGE requested %llu got %u Mbps\n", mbps,
> +		hsfreq->mbps);
> +
> +	*phypll = PHYPLL_HSFREQRANGE(hsfreq->reg);
> +
> +	return 0;
> +}
> +
> +static int rcar_csi2_start(struct rcar_csi2 *priv)
> +{
> +	const struct rcar_csi2_format *format;
> +	struct v4l2_subdev_format fmt;
> +	struct media_pad *source_pad;
> +	struct v4l2_subdev *source = NULL;
> +	struct v4l2_mbus_framefmt *mf = &fmt.format;
> +	u32 phycnt, phypll, tmp;
> +	u32 vcdt = 0, vcdt2 = 0;
> +	unsigned int i;
> +	int ret;
> +
> +	source_pad =
> +		media_entity_remote_pad(&priv->subdev.entity.pads[RCAR_CSI2_SINK]);
> +	if (!source_pad) {
> +		dev_err(priv->dev, "Could not find remote source pad\n");
> +		return -ENODEV;
> +	}
> +
> +	source = media_entity_to_v4l2_subdev(source_pad->entity);
> +	if (!source) {
> +		dev_err(priv->dev, "Could not find remote subdevice\n");
> +		return -ENODEV;
> +	}
> +
> +	dev_dbg(priv->dev, "Using source %s pad: %u\n", source->name,
> +		source_pad->index);
> +
> +	fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
> +	fmt.pad = source_pad->index;
> +	ret = v4l2_subdev_call(source, pad, get_fmt, NULL, &fmt);
> +	if (ret)
> +		return ret;
> +
> +	dev_dbg(priv->dev, "Input size (%dx%d%c)\n", mf->width,
> +		mf->height, mf->field == V4L2_FIELD_NONE ? 'p' : 'i');
> +
> +	/*
> +	 * Enable all Virtual Channels
> +	 *
> +	 * NOTE: I'ts not possible to get individual format for each

I'ts -> It's

> +	 *       source virtual channel. Once this is possible in V4L2
> +	 *       it should be used here.
> +	 */
> +	for (i = 0; i < 4; i++) {
> +

Remove empty line.

> +		format = rcar_csi2_code_to_fmt(mf->code);
> +		if (!format) {
> +			dev_err(priv->dev, "Unsupported media bus format: %d\n",
> +				mf->code);
> +			return -EINVAL;
> +		}
> +
> +		tmp = VCDT_SEL_VC(i) | VCDT_VCDTN_EN | VCDT_SEL_DTN_ON |
> +			VCDT_SEL_DT(format->datatype);
> +
> +		/* Store in correct reg and offset */
> +		if (i < 2)
> +			vcdt |= tmp << ((i % 2) * 16);
> +		else
> +			vcdt2 |= tmp << ((i % 2) * 16);
> +	}
> +
> +	switch (priv->lanes) {
> +	case 1:
> +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_0;
> +		break;
> +	case 2:
> +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_1 | PHYCNT_ENABLE_0;
> +		break;
> +	case 4:
> +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_3 | PHYCNT_ENABLE_2 |
> +			PHYCNT_ENABLE_1 | PHYCNT_ENABLE_0;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	ret = rcar_csi2_calc_phypll(priv, source, mf, &phypll);
> +	if (ret)
> +		return ret;
> +
> +	/* Init */
> +	rcar_csi2_write(priv, TREF_REG, TREF_TREF);
> +	rcar_csi2_reset(priv);
> +	rcar_csi2_write(priv, PHTC_REG, 0);
> +
> +	/* Configure */
> +	rcar_csi2_write(priv, FLD_REG, FLD_FLD_NUM(2) | FLD_FLD_EN4 |
> +			FLD_FLD_EN3 | FLD_FLD_EN2 | FLD_FLD_EN);
> +	rcar_csi2_write(priv, VCDT_REG, vcdt);
> +	rcar_csi2_write(priv, VCDT2_REG, vcdt2);
> +	/* Lanes are zero indexed */
> +	rcar_csi2_write(priv, LSWAP_REG,
> +			LSWAP_L0SEL(priv->lane_swap[0] - 1) |
> +			LSWAP_L1SEL(priv->lane_swap[1] - 1) |
> +			LSWAP_L2SEL(priv->lane_swap[2] - 1) |
> +			LSWAP_L3SEL(priv->lane_swap[3] - 1));
> +
> +	/* Start */
> +	rcar_csi2_write(priv, PHYPLL_REG, phypll);
> +	rcar_csi2_write(priv, PHYCNT_REG, phycnt);
> +	rcar_csi2_write(priv, LINKCNT_REG, LINKCNT_MONITOR_EN |
> +			LINKCNT_REG_MONI_PACT_EN | LINKCNT_ICLK_NONSTOP);
> +	rcar_csi2_write(priv, PHYCNT_REG, phycnt | PHYCNT_SHUTDOWNZ);
> +	rcar_csi2_write(priv, PHYCNT_REG, phycnt | PHYCNT_SHUTDOWNZ |
> +			PHYCNT_RSTZ);
> +
> +	return rcar_csi2_wait_phy_start(priv);
> +}
> +
> +static void rcar_csi2_stop(struct rcar_csi2 *priv)
> +{
> +	rcar_csi2_write(priv, PHYCNT_REG, 0);
> +
> +	rcar_csi2_reset(priv);
> +}
> +
> +static int rcar_csi2_sd_info(struct rcar_csi2 *priv, struct v4l2_subdev **sd)
> +{
> +	struct media_pad *pad;
> +
> +	pad = media_entity_remote_pad(&priv->pads[RCAR_CSI2_SINK]);
> +	if (!pad) {
> +		dev_err(priv->dev, "Could not find remote pad\n");
> +		return -ENODEV;
> +	}
> +
> +	*sd = media_entity_to_v4l2_subdev(pad->entity);
> +	if (!*sd) {
> +		dev_err(priv->dev, "Could not find remote subdevice\n");
> +		return -ENODEV;
> +	}
> +
> +	return 0;
> +}
> +
> +static int rcar_csi2_s_stream(struct v4l2_subdev *sd, int enable)
> +{
> +	struct rcar_csi2 *priv = sd_to_csi2(sd);
> +	struct v4l2_subdev *nextsd;
> +	int ret;
> +
> +	mutex_lock(&priv->lock);
> +
> +	ret = rcar_csi2_sd_info(priv, &nextsd);
> +	if (ret)
> +		goto out;
> +
> +	priv->stream_count += enable ? 1 : -1;
> +
> +	if (enable && priv->stream_count == 1) {
> +		ret =  rcar_csi2_start(priv);
> +		if (ret)
> +			goto out;
> +		ret = v4l2_subdev_call(nextsd, video, s_stream, 1);
> +
> +	} else if (!enable && !priv->stream_count) {
> +		rcar_csi2_stop(priv);
> +		ret = v4l2_subdev_call(nextsd, video, s_stream, 0);
> +	}
> +out:
> +	mutex_unlock(&priv->lock);
> +
> +	return ret;
> +}
> +
> +static int rcar_csi2_s_power(struct v4l2_subdev *sd, int on)
> +{
> +	struct rcar_csi2 *priv = sd_to_csi2(sd);
> +
> +	if (on)
> +		pm_runtime_get_sync(priv->dev);
> +	else
> +		pm_runtime_put(priv->dev);
> +
> +	return 0;
> +}
> +
> +static int rcar_csi2_set_pad_format(struct v4l2_subdev *sd,
> +				    struct v4l2_subdev_pad_config *cfg,
> +				    struct v4l2_subdev_format *format)
> +{
> +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> +
> +	if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE)
> +		priv->mf = format->format;
> +
> +	return 0;
> +}
> +
> +static int rcar_csi2_get_pad_format(struct v4l2_subdev *sd,
> +				    struct v4l2_subdev_pad_config *cfg,
> +				    struct v4l2_subdev_format *format)
> +{
> +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> +
> +	format->format = priv->mf;
> +
> +	return 0;
> +}
> +
> +static const struct v4l2_subdev_video_ops rcar_csi2_video_ops = {
> +	.s_stream = rcar_csi2_s_stream,
> +};
> +
> +static const struct v4l2_subdev_core_ops rcar_csi2_subdev_core_ops = {
> +	.s_power = rcar_csi2_s_power,
> +};
> +
> +static const struct v4l2_subdev_pad_ops rcar_csi2_pad_ops = {
> +	.set_fmt = rcar_csi2_set_pad_format,
> +	.get_fmt = rcar_csi2_get_pad_format,
> +};
> +
> +static const struct v4l2_subdev_ops rcar_csi2_subdev_ops = {
> +	.video	= &rcar_csi2_video_ops,
> +	.core	= &rcar_csi2_subdev_core_ops,
> +	.pad	= &rcar_csi2_pad_ops,
> +};
> +
> +/* -----------------------------------------------------------------------------
> + * Async and registered of subdevices and links
> + */
> +
> +#define notifier_to_priv(n) container_of(n, struct rcar_csi2, notifier)
> +
> +static int rcar_csi2_notify_complete(struct v4l2_async_notifier *notifier)
> +{
> +	struct rcar_csi2 *priv = notifier_to_priv(notifier);
> +	int ret;
> +
> +	ret = v4l2_device_register_subdev_nodes(priv->subdev.v4l2_dev);
> +	if (ret) {
> +		dev_err(priv->dev, "Failed to register subdev nodes\n");
> +		return ret;
> +	}
> +
> +	return media_create_pad_link(&priv->remote.subdev->entity,
> +				     priv->remote.source_pad,
> +				     &priv->subdev.entity, 0,
> +				     MEDIA_LNK_FL_ENABLED |
> +				     MEDIA_LNK_FL_IMMUTABLE);

Shouldn't the link be created before the register subdev nodes are registered?

Usually that's done at the very end after everything else has been configured
correctly.

> +}
> +
> +static int rcar_csi2_notify_bound(struct v4l2_async_notifier *notifier,
> +				   struct v4l2_subdev *subdev,
> +				   struct v4l2_async_subdev *asd)
> +{
> +	struct rcar_csi2 *priv = notifier_to_priv(notifier);
> +	int ret;
> +
> +	v4l2_set_subdev_hostdata(subdev, priv);
> +
> +	ret = media_entity_pad_from_fwnode(&subdev->entity,
> +					   priv->remote.fwnode,
> +					   MEDIA_PAD_FL_SOURCE,
> +					   &priv->remote.source_pad);
> +	if (ret) {
> +		dev_err(priv->dev, "Failed to find pad for %s\n",
> +			subdev->name);
> +		return ret;
> +	}
> +
> +	dev_dbg(priv->dev, "Bound %s pad: %d\n", subdev->name,
> +		priv->remote.source_pad);
> +	priv->remote.subdev = subdev;
> +
> +	return 0;
> +}
> +static void rcar_csi2_notify_unbind(struct v4l2_async_notifier *notifier,
> +				     struct v4l2_subdev *subdev,
> +				     struct v4l2_async_subdev *asd)
> +{
> +	struct rcar_csi2 *priv = notifier_to_priv(notifier);
> +
> +	dev_dbg(priv->dev, "Unbind %s\n", subdev->name);
> +	priv->remote.subdev = NULL;
> +}
> +
> +static int rcar_csi2_registered(struct v4l2_subdev *sd)
> +{
> +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> +	struct v4l2_async_subdev **subdevs = NULL;
> +	int ret;
> +
> +	subdevs = devm_kzalloc(priv->dev, sizeof(*subdevs), GFP_KERNEL);
> +	if (subdevs == NULL)
> +		return -ENOMEM;
> +
> +	subdevs[0] = &priv->remote.asd;
> +
> +	priv->notifier.num_subdevs = 1;
> +	priv->notifier.subdevs = subdevs;
> +	priv->notifier.bound = rcar_csi2_notify_bound;
> +	priv->notifier.unbind = rcar_csi2_notify_unbind;
> +	priv->notifier.complete = rcar_csi2_notify_complete;
> +
> +	ret = v4l2_async_subnotifier_register(&priv->subdev, &priv->notifier);
> +	if (ret < 0) {
> +		dev_err(priv->dev, "Notifier registration failed\n");
> +		return ret;
> +	}
> +
> +	return 0;
> +}

Hmm, I'm trying to understand this, and I got one question. There are at least
two complete callbacks: rcar_csi2_notify_complete and the bridge driver's
complete callback. Am I right that the bridge driver's complete callback is
called as soon as this function exists (assuming this is the only subdev)?

So the bridge driver thinks it is complete when in reality this subdev may
be waiting on newly registered subdevs?

If I am right, then my question is if that is what we want. If I am wrong,
then what did I miss?

> +
> +static void rcar_csi2_unregistered(struct v4l2_subdev *sd)
> +{
> +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> +
> +	v4l2_async_subnotifier_unregister(&priv->notifier);
> +}
> +
> +static const struct v4l2_subdev_internal_ops rcar_csi2_internal_ops = {
> +	.registered = rcar_csi2_registered,
> +	.unregistered = rcar_csi2_unregistered,
> +};
> +
> +static int rcar_csi2_parse_dt_subdevice(struct rcar_csi2 *priv)
> +{
> +	struct device_node *remote, *ep;
> +	struct v4l2_fwnode_endpoint v4l2_ep;
> +	int ret;
> +
> +	ep = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0);
> +	if (!ep) {
> +		dev_err(priv->dev, "Not connected to subdevice\n");
> +		return -EINVAL;
> +	}
> +
> +	ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &v4l2_ep);
> +	if (ret) {
> +		dev_err(priv->dev, "Could not parse v4l2 endpoint\n");
> +		of_node_put(ep);
> +		return -EINVAL;
> +	}
> +
> +	if (v4l2_ep.bus_type != V4L2_MBUS_CSI2) {
> +		dev_err(priv->dev, "Unknown media bus type: 0x%x\n",
> +			v4l2_ep.bus_type);
> +		of_node_put(ep);
> +		return -EINVAL;
> +	}
> +
> +	priv->remote.fwnode =
> +		fwnode_graph_get_remote_endpoint(of_fwnode_handle(ep));
> +
> +	remote = of_graph_get_remote_port_parent(ep);
> +	of_node_put(ep);
> +	if (!remote) {
> +		dev_err(priv->dev, "No subdevice found for endpoint '%s'\n",
> +			of_node_full_name(ep));
> +		return -EINVAL;
> +	}
> +
> +	priv->remote.asd.match.fwnode.fwnode = of_fwnode_handle(remote);
> +	priv->remote.asd.match_type = V4L2_ASYNC_MATCH_FWNODE;
> +
> +	dev_dbg(priv->dev, "Found '%s'\n", of_node_full_name(remote));
> +
> +	return 0;
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Platform Device Driver
> + */
> +
> +static const struct of_device_id rcar_csi2_of_table[] = {
> +	{ .compatible = "renesas,rcar-gen3-csi2" },
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(of, rcar_csi2_of_table);
> +
> +static const struct media_entity_operations rcar_csi2_entity_ops = {
> +	.link_validate = v4l2_subdev_link_validate,
> +};
> +
> +static int rcar_csi2_parse_dt_settings(struct rcar_csi2 *priv)
> +{
> +	struct v4l2_fwnode_endpoint v4l2_ep;
> +	struct device_node *ep;
> +	unsigned int i;
> +	int ret;
> +
> +	ep = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0);
> +	if (!ep)
> +		return -EINVAL;
> +
> +	ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &v4l2_ep);
> +	of_node_put(ep);
> +	if (ret) {
> +		dev_err(priv->dev, "Could not parse v4l2 endpoint\n");
> +		return -EINVAL;
> +	}
> +
> +	if (v4l2_ep.bus_type != V4L2_MBUS_CSI2) {
> +		dev_err(priv->dev, "Unsupported media bus type for %s\n",
> +			of_node_full_name(ep));
> +		return -EINVAL;
> +	}
> +
> +	priv->lanes = v4l2_ep.bus.mipi_csi2.num_data_lanes;
> +	if (priv->lanes != 1 && priv->lanes != 2 && priv->lanes != 4) {
> +		dev_err(priv->dev, "Unsupported number of data-lanes: %d\n",
> +			priv->lanes);
> +		return -EINVAL;
> +	}
> +
> +	for (i = 0; i < ARRAY_SIZE(priv->lane_swap); i++) {
> +		priv->lane_swap[i] = i < priv->lanes ?
> +			v4l2_ep.bus.mipi_csi2.data_lanes[i] : i;
> +
> +		/* Check for valid lane number */
> +		if (priv->lane_swap[i] < 1 || priv->lane_swap[i] > 4) {
> +			dev_err(priv->dev, "data-lanes must be in 1-4 range\n");
> +			return -EINVAL;
> +		}
> +	}
> +
> +	return 0;
> +}
> +
> +static int rcar_csi2_probe_resources(struct rcar_csi2 *priv,
> +				     struct platform_device *pdev)
> +{
> +	struct resource *mem;
> +	int irq;
> +
> +	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!mem)
> +		return -ENODEV;
> +
> +	priv->base = devm_ioremap_resource(&pdev->dev, mem);
> +	if (IS_ERR(priv->base))
> +		return PTR_ERR(priv->base);
> +
> +	irq = platform_get_irq(pdev, 0);
> +	if (irq < 0)
> +		return irq;
> +
> +	return 0;
> +}
> +
> +static int rcar_csi2_probe(struct platform_device *pdev)
> +{
> +	struct rcar_csi2 *priv;
> +	unsigned int i;
> +	int ret;
> +
> +	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
> +
> +	priv->dev = &pdev->dev;
> +
> +	mutex_init(&priv->lock);
> +	priv->stream_count = 0;
> +
> +	ret = rcar_csi2_parse_dt_settings(priv);
> +	if (ret)
> +		return ret;
> +
> +	ret = rcar_csi2_parse_dt_subdevice(priv);
> +	if (ret)
> +		return ret;
> +
> +	ret = rcar_csi2_probe_resources(priv, pdev);
> +	if (ret) {
> +		dev_err(priv->dev, "Failed to get resources\n");
> +		return ret;
> +	}
> +
> +	platform_set_drvdata(pdev, priv);
> +
> +	priv->subdev.owner = THIS_MODULE;
> +	priv->subdev.dev = &pdev->dev;
> +	v4l2_subdev_init(&priv->subdev, &rcar_csi2_subdev_ops);
> +	v4l2_set_subdevdata(&priv->subdev, &pdev->dev);
> +	snprintf(priv->subdev.name, V4L2_SUBDEV_NAME_SIZE, "%s %s",
> +		 KBUILD_MODNAME, dev_name(&pdev->dev));
> +	priv->subdev.flags = V4L2_SUBDEV_FL_HAS_DEVNODE;
> +	priv->subdev.internal_ops = &rcar_csi2_internal_ops;
> +
> +	priv->subdev.entity.function = MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER;
> +	priv->subdev.entity.ops = &rcar_csi2_entity_ops;
> +
> +	priv->pads[RCAR_CSI2_SINK].flags = MEDIA_PAD_FL_SINK;
> +	for (i = RCAR_CSI2_SOURCE_VC0; i < NR_OF_RCAR_CSI2_PAD; i++)
> +		priv->pads[i].flags = MEDIA_PAD_FL_SOURCE;
> +
> +	ret = media_entity_pads_init(&priv->subdev.entity, NR_OF_RCAR_CSI2_PAD,
> +				     priv->pads);
> +	if (ret)
> +		return ret;
> +
> +	ret = v4l2_async_register_subdev(&priv->subdev);
> +	if (ret < 0)
> +		return ret;
> +
> +	pm_runtime_enable(&pdev->dev);
> +
> +	dev_info(priv->dev, "%d lanes found\n", priv->lanes);
> +
> +	return 0;
> +}
> +
> +static int rcar_csi2_remove(struct platform_device *pdev)
> +{
> +	struct rcar_csi2 *priv = platform_get_drvdata(pdev);
> +
> +	v4l2_async_unregister_subdev(&priv->subdev);
> +
> +	pm_runtime_disable(&pdev->dev);
> +
> +	return 0;
> +}
> +
> +static struct platform_driver __refdata rcar_csi2_pdrv = {
> +	.remove	= rcar_csi2_remove,
> +	.probe	= rcar_csi2_probe,
> +	.driver	= {
> +		.name	= "rcar-csi2",
> +		.of_match_table	= of_match_ptr(rcar_csi2_of_table),
> +	},
> +};
> +
> +module_platform_driver(rcar_csi2_pdrv);
> +
> +MODULE_AUTHOR("Niklas Söderlund <niklas.soderlund@ragnatech.se>");
> +MODULE_DESCRIPTION("Renesas R-Car MIPI CSI-2 receiver");
> +MODULE_LICENSE("GPL v2");
> 

Regards,

	Hans

Re: [PATCH v7 2/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver driver

[Niklas Söderlund]

Hi Hans,

Thanks for your comments.

On 2017-05-29 13:16:23 +0200, Hans Verkuil wrote:
> On 05/24/2017 02:13 AM, Niklas Söderlund wrote:
> > From: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> > 
> > A V4L2 driver for Renesas R-Car MIPI CSI-2 receiver. The driver
> > supports the rcar-vin driver on R-Car Gen3 SoCs where separate CSI-2
> > hardware blocks are connected between the video sources and the video
> > grabbers (VIN).
> > 
> > Driver is based on a prototype by Koji Matsuoka in the Renesas BSP.
> > 
> > Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> > ---
> >   drivers/media/platform/rcar-vin/Kconfig     |  12 +
> >   drivers/media/platform/rcar-vin/Makefile    |   1 +
> >   drivers/media/platform/rcar-vin/rcar-csi2.c | 867 ++++++++++++++++++++++++++++
> >   3 files changed, 880 insertions(+)
> >   create mode 100644 drivers/media/platform/rcar-vin/rcar-csi2.c
> > 
> > diff --git a/drivers/media/platform/rcar-vin/Kconfig b/drivers/media/platform/rcar-vin/Kconfig
> > index af4c98b44d2e22cb..6875f30c1ae42631 100644
> > --- a/drivers/media/platform/rcar-vin/Kconfig
> > +++ b/drivers/media/platform/rcar-vin/Kconfig
> > @@ -1,3 +1,15 @@
> > +config VIDEO_RCAR_CSI2
> > +	tristate "R-Car MIPI CSI-2 Receiver"
> > +	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && OF
> > +	depends on ARCH_RENESAS || COMPILE_TEST
> > +	select V4L2_FWNODE
> > +	---help---
> > +	  Support for Renesas R-Car MIPI CSI-2 receiver.
> > +	  Supports R-Car Gen3 SoCs.
> > +
> > +	  To compile this driver as a module, choose M here: the
> > +	  module will be called rcar-csi2.
> > +
> >   config VIDEO_RCAR_VIN
> >   	tristate "R-Car Video Input (VIN) Driver"
> >   	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && OF && HAS_DMA && MEDIA_CONTROLLER
> > diff --git a/drivers/media/platform/rcar-vin/Makefile b/drivers/media/platform/rcar-vin/Makefile
> > index 48c5632c21dc060b..5ab803d3e7c1aa57 100644
> > --- a/drivers/media/platform/rcar-vin/Makefile
> > +++ b/drivers/media/platform/rcar-vin/Makefile
> > @@ -1,3 +1,4 @@
> >   rcar-vin-objs = rcar-core.o rcar-dma.o rcar-v4l2.o
> > +obj-$(CONFIG_VIDEO_RCAR_CSI2) += rcar-csi2.o
> >   obj-$(CONFIG_VIDEO_RCAR_VIN) += rcar-vin.o
> > diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
> > new file mode 100644
> > index 0000000000000000..1175f1fe4b139a13
> > --- /dev/null
> > +++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
> > @@ -0,0 +1,867 @@
> > +/*
> > + * Driver for Renesas R-Car MIPI CSI-2 Receiver
> > + *
> > + * Copyright (C) 2017 Renesas Electronics Corp.
> > + *
> > + * This program is free software; you can redistribute  it and/or modify it
> > + * under  the terms of  the GNU General  Public License as published by the
> > + * Free Software Foundation;  either version 2 of the  License, or (at your
> > + * option) any later version.
> > + */
> > +
> > +#include <linux/delay.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/io.h>
> > +#include <linux/module.h>
> > +#include <linux/of.h>
> > +#include <linux/of_device.h>
> > +#include <linux/of_graph.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/pm_runtime.h>
> > +
> > +#include <media/v4l2-ctrls.h>
> > +#include <media/v4l2-device.h>
> > +#include <media/v4l2-fwnode.h>
> > +#include <media/v4l2-mc.h>
> > +#include <media/v4l2-subdev.h>
> > +
> > +/* Register offsets and bits */
> > +
> > +/* Control Timing Select */
> > +#define TREF_REG			0x00
> > +#define TREF_TREF			(1 << 0)
> > +
> > +/* Software Reset */
> > +#define SRST_REG			0x04
> > +#define SRST_SRST			(1 << 0)
> > +
> > +/* PHY Operation Control */
> > +#define PHYCNT_REG			0x08
> > +#define PHYCNT_SHUTDOWNZ		(1 << 17)
> > +#define PHYCNT_RSTZ			(1 << 16)
> > +#define PHYCNT_ENABLECLK		(1 << 4)
> > +#define PHYCNT_ENABLE_3			(1 << 3)
> > +#define PHYCNT_ENABLE_2			(1 << 2)
> > +#define PHYCNT_ENABLE_1			(1 << 1)
> > +#define PHYCNT_ENABLE_0			(1 << 0)
> > +
> > +/* Checksum Control */
> > +#define CHKSUM_REG			0x0c
> > +#define CHKSUM_ECC_EN			(1 << 1)
> > +#define CHKSUM_CRC_EN			(1 << 0)
> > +
> > +/*
> > + * Channel Data Type Select
> > + * VCDT[0-15]:  Channel 1 VCDT[16-31]:  Channel 2
> > + * VCDT2[0-15]: Channel 3 VCDT2[16-31]: Channel 4
> > + */
> > +#define VCDT_REG			0x10
> > +#define VCDT2_REG			0x14
> > +#define VCDT_VCDTN_EN			(1 << 15)
> > +#define VCDT_SEL_VC(n)			(((n) & 0x3) << 8)
> > +#define VCDT_SEL_DTN_ON			(1 << 6)
> > +#define VCDT_SEL_DT(n)			(((n) & 0x3f) << 0)
> > +
> > +/* Frame Data Type Select */
> > +#define FRDT_REG			0x18
> > +
> > +/* Field Detection Control */
> > +#define FLD_REG				0x1c
> > +#define FLD_FLD_NUM(n)			(((n) & 0xff) << 16)
> > +#define FLD_FLD_EN4			(1 << 3)
> > +#define FLD_FLD_EN3			(1 << 2)
> > +#define FLD_FLD_EN2			(1 << 1)
> > +#define FLD_FLD_EN			(1 << 0)
> > +
> > +/* Automatic Standby Control */
> > +#define ASTBY_REG			0x20
> > +
> > +/* Long Data Type Setting 0 */
> > +#define LNGDT0_REG			0x28
> > +
> > +/* Long Data Type Setting 1 */
> > +#define LNGDT1_REG			0x2c
> > +
> > +/* Interrupt Enable */
> > +#define INTEN_REG			0x30
> > +
> > +/* Interrupt Source Mask */
> > +#define INTCLOSE_REG			0x34
> > +
> > +/* Interrupt Status Monitor */
> > +#define INTSTATE_REG			0x38
> > +
> > +/* Interrupt Error Status Monitor */
> > +#define INTERRSTATE_REG			0x3c
> > +
> > +/* Short Packet Data */
> > +#define SHPDAT_REG			0x40
> > +
> > +/* Short Packet Count */
> > +#define SHPCNT_REG			0x44
> > +
> > +/* LINK Operation Control */
> > +#define LINKCNT_REG			0x48
> > +#define LINKCNT_MONITOR_EN		(1 << 31)
> > +#define LINKCNT_REG_MONI_PACT_EN	(1 << 25)
> > +#define LINKCNT_ICLK_NONSTOP		(1 << 24)
> > +
> > +/* Lane Swap */
> > +#define LSWAP_REG			0x4c
> > +#define LSWAP_L3SEL(n)			(((n) & 0x3) << 6)
> > +#define LSWAP_L2SEL(n)			(((n) & 0x3) << 4)
> > +#define LSWAP_L1SEL(n)			(((n) & 0x3) << 2)
> > +#define LSWAP_L0SEL(n)			(((n) & 0x3) << 0)
> > +
> > +/* PHY Test Interface Clear */
> > +#define PHTC_REG			0x58
> > +#define PHTC_TESTCLR			(1 << 0)
> > +
> > +/* PHY Frequency Control */
> > +#define PHYPLL_REG			0x68
> > +#define PHYPLL_HSFREQRANGE(n)		((n) << 16)
> > +
> > +struct phypll_hsfreqrange {
> > +	unsigned int	mbps;
> > +	unsigned char	reg;
> > +};
> > +
> > +static const struct phypll_hsfreqrange phypll_hsfreqrange_map[] = {
> > +	{ .mbps =   80,	.reg = 0x00 },
> > +	{ .mbps =   90,	.reg = 0x10 },
> > +	{ .mbps =  100,	.reg = 0x20 },
> > +	{ .mbps =  110,	.reg = 0x30 },
> > +	{ .mbps =  120,	.reg = 0x01 },
> > +	{ .mbps =  130,	.reg = 0x11 },
> > +	{ .mbps =  140,	.reg = 0x21 },
> > +	{ .mbps =  150,	.reg = 0x31 },
> > +	{ .mbps =  160,	.reg = 0x02 },
> > +	{ .mbps =  170,	.reg = 0x12 },
> > +	{ .mbps =  180,	.reg = 0x22 },
> > +	{ .mbps =  190,	.reg = 0x32 },
> > +	{ .mbps =  205,	.reg = 0x03 },
> > +	{ .mbps =  220,	.reg = 0x13 },
> > +	{ .mbps =  235,	.reg = 0x23 },
> > +	{ .mbps =  250,	.reg = 0x33 },
> > +	{ .mbps =  275,	.reg = 0x04 },
> > +	{ .mbps =  300,	.reg = 0x14 },
> > +	{ .mbps =  325,	.reg = 0x05 },
> > +	{ .mbps =  350,	.reg = 0x15 },
> > +	{ .mbps =  400,	.reg = 0x25 },
> > +	{ .mbps =  450,	.reg = 0x06 },
> > +	{ .mbps =  500,	.reg = 0x16 },
> > +	{ .mbps =  550,	.reg = 0x07 },
> > +	{ .mbps =  600,	.reg = 0x17 },
> > +	{ .mbps =  650,	.reg = 0x08 },
> > +	{ .mbps =  700,	.reg = 0x18 },
> > +	{ .mbps =  750,	.reg = 0x09 },
> > +	{ .mbps =  800,	.reg = 0x19 },
> > +	{ .mbps =  850,	.reg = 0x29 },
> > +	{ .mbps =  900,	.reg = 0x39 },
> > +	{ .mbps =  950,	.reg = 0x0A },
> > +	{ .mbps = 1000,	.reg = 0x1A },
> > +	{ .mbps = 1050,	.reg = 0x2A },
> > +	{ .mbps = 1100,	.reg = 0x3A },
> > +	{ .mbps = 1150,	.reg = 0x0B },
> > +	{ .mbps = 1200,	.reg = 0x1B },
> > +	{ .mbps = 1250,	.reg = 0x2B },
> > +	{ .mbps = 1300,	.reg = 0x3B },
> > +	{ .mbps = 1350,	.reg = 0x0C },
> > +	{ .mbps = 1400,	.reg = 0x1C },
> > +	{ .mbps = 1450,	.reg = 0x2C },
> > +	{ .mbps = 1500,	.reg = 0x3C },
> > +	/* guard */
> > +	{ .mbps =   0,	.reg = 0x00 },
> > +};
> > +
> > +/* PHY ESC Error Monitor */
> > +#define PHEERM_REG			0x74
> > +
> > +/* PHY Clock Lane Monitor */
> > +#define PHCLM_REG			0x78
> > +
> > +/* PHY Data Lane Monitor */
> > +#define PHDLM_REG			0x7c
> > +
> > +struct rcar_csi2_format {
> > +	unsigned int code;
> > +	unsigned int datatype;
> > +	unsigned int bpp;
> > +};
> > +
> > +static const struct rcar_csi2_format rcar_csi2_formats[] = {
> > +	{ .code = MEDIA_BUS_FMT_RGB888_1X24,	.datatype = 0x24, .bpp = 24},
> > +	{ .code = MEDIA_BUS_FMT_UYVY8_1X16,	.datatype = 0x1e, .bpp = 8 },
> > +	{ .code = MEDIA_BUS_FMT_UYVY8_2X8,	.datatype = 0x1e, .bpp = 8 },
> > +	{ .code = MEDIA_BUS_FMT_YUYV10_2X10,	.datatype = 0x1e, .bpp = 8 },
> > +};
> > +
> > +static const struct rcar_csi2_format *rcar_csi2_code_to_fmt(unsigned int code)
> > +{
> > +	int i;
> > +
> > +	for (i = 0; i < ARRAY_SIZE(rcar_csi2_formats); i++)
> > +		if (rcar_csi2_formats[i].code == code)
> > +			return rcar_csi2_formats + i;
> > +	return NULL;
> > +}
> > +
> > +enum rcar_csi2_pads {
> > +	RCAR_CSI2_SINK,
> > +	RCAR_CSI2_SOURCE_VC0,
> > +	RCAR_CSI2_SOURCE_VC1,
> > +	RCAR_CSI2_SOURCE_VC2,
> > +	RCAR_CSI2_SOURCE_VC3,
> > +	NR_OF_RCAR_CSI2_PAD,
> > +};
> > +
> > +struct rcar_csi2 {
> > +	struct device *dev;
> > +	void __iomem *base;
> > +
> > +	unsigned short lanes;
> > +	unsigned char lane_swap[4];
> > +
> > +	struct v4l2_subdev subdev;
> > +	struct media_pad pads[NR_OF_RCAR_CSI2_PAD];
> > +
> > +	struct v4l2_mbus_framefmt mf;
> > +
> > +	struct mutex lock;
> > +	int stream_count;
> > +
> > +	struct v4l2_async_notifier notifier;
> > +	struct {
> > +		struct v4l2_async_subdev asd;
> > +		struct v4l2_subdev *subdev;
> > +		struct fwnode_handle *fwnode;
> > +		unsigned int source_pad;
> > +	} remote;
> > +};
> > +
> > +static inline struct rcar_csi2 *sd_to_csi2(struct v4l2_subdev *sd)
> > +{
> > +	return container_of(sd, struct rcar_csi2, subdev);
> > +}
> > +
> > +static u32 rcar_csi2_read(struct rcar_csi2 *priv, unsigned int reg)
> > +{
> > +	return ioread32(priv->base + reg);
> > +}
> > +
> > +static void rcar_csi2_write(struct rcar_csi2 *priv, unsigned int reg, u32 data)
> > +{
> > +	iowrite32(data, priv->base + reg);
> > +}
> > +
> > +static void rcar_csi2_reset(struct rcar_csi2 *priv)
> > +{
> > +	rcar_csi2_write(priv, SRST_REG, SRST_SRST);
> > +	rcar_csi2_write(priv, SRST_REG, 0);
> > +}
> > +
> > +static int rcar_csi2_wait_phy_start(struct rcar_csi2 *priv)
> > +{
> > +	int timeout;
> > +
> > +	/* Wait for the clock and data lanes to enter LP-11 state. */
> > +	for (timeout = 100; timeout >= 0; timeout--) {
> > +		const u32 lane_mask = (1 << priv->lanes) - 1;
> > +
> > +		if ((rcar_csi2_read(priv, PHCLM_REG) & 1) == 1 &&
> > +		    (rcar_csi2_read(priv, PHDLM_REG) & lane_mask) == lane_mask)
> > +			return 0;
> > +
> > +		msleep(20);
> > +	}
> > +
> > +	dev_err(priv->dev, "Timeout waiting for LP-11 state\n");
> > +
> > +	return -ETIMEDOUT;
> > +}
> > +
> > +static int rcar_csi2_calc_phypll(struct rcar_csi2 *priv,
> > +				 struct v4l2_subdev *source,
> > +				 struct v4l2_mbus_framefmt *mf,
> > +				 u32 *phypll)
> > +{
> > +	const struct phypll_hsfreqrange *hsfreq;
> > +	const struct rcar_csi2_format *format;
> > +	struct v4l2_ext_controls ctrls;
> > +	struct v4l2_ext_control ctrl;
> > +	u64 mbps;
> > +	int ret;
> > +
> > +	memset(&ctrls, 0, sizeof(ctrls));
> > +	memset(&ctrl, 0, sizeof(ctrl));
> > +
> > +	ctrl.id = V4L2_CID_PIXEL_RATE;
> > +
> > +	ctrls.count = 1;
> > +	ctrls.controls = &ctrl;
> > +
> > +	ret = v4l2_g_ext_ctrls(source->ctrl_handler, &ctrls);
> > +	if (ret < 0) {
> > +		dev_err(priv->dev, "no link freq control in subdev %s\n",
> > +			source->name);
> > +		return ret;
> > +	}
> 
> Please use v4l2_ctrl_g_ctrl_int64 instead. v4l2_g_ext_ctrls is not intended to
> be used by drivers.

Thanks will do this for the next version.

> 
> > +
> > +	format = rcar_csi2_code_to_fmt(mf->code);
> > +	if (!format) {
> > +		dev_err(priv->dev, "Unknown format: %d\n", mf->code);
> > +		return -EINVAL;
> > +	}
> > +
> > +	mbps = ctrl.value64 * format->bpp;
> > +	do_div(mbps, priv->lanes * 1000000);
> > +
> > +	for (hsfreq = phypll_hsfreqrange_map; hsfreq->mbps != 0; hsfreq++)
> > +		if (hsfreq->mbps >= mbps)
> > +			break;
> > +
> > +	if (!hsfreq->mbps) {
> > +		dev_err(priv->dev, "Unsupported PHY speed (%llu Mbps)", mbps);
> > +		return -ERANGE;
> > +	}
> > +
> > +	dev_dbg(priv->dev, "PHY HSFREQRANGE requested %llu got %u Mbps\n", mbps,
> > +		hsfreq->mbps);
> > +
> > +	*phypll = PHYPLL_HSFREQRANGE(hsfreq->reg);
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_start(struct rcar_csi2 *priv)
> > +{
> > +	const struct rcar_csi2_format *format;
> > +	struct v4l2_subdev_format fmt;
> > +	struct media_pad *source_pad;
> > +	struct v4l2_subdev *source = NULL;
> > +	struct v4l2_mbus_framefmt *mf = &fmt.format;
> > +	u32 phycnt, phypll, tmp;
> > +	u32 vcdt = 0, vcdt2 = 0;
> > +	unsigned int i;
> > +	int ret;
> > +
> > +	source_pad =
> > +		media_entity_remote_pad(&priv->subdev.entity.pads[RCAR_CSI2_SINK]);
> > +	if (!source_pad) {
> > +		dev_err(priv->dev, "Could not find remote source pad\n");
> > +		return -ENODEV;
> > +	}
> > +
> > +	source = media_entity_to_v4l2_subdev(source_pad->entity);
> > +	if (!source) {
> > +		dev_err(priv->dev, "Could not find remote subdevice\n");
> > +		return -ENODEV;
> > +	}
> > +
> > +	dev_dbg(priv->dev, "Using source %s pad: %u\n", source->name,
> > +		source_pad->index);
> > +
> > +	fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
> > +	fmt.pad = source_pad->index;
> > +	ret = v4l2_subdev_call(source, pad, get_fmt, NULL, &fmt);
> > +	if (ret)
> > +		return ret;
> > +
> > +	dev_dbg(priv->dev, "Input size (%dx%d%c)\n", mf->width,
> > +		mf->height, mf->field == V4L2_FIELD_NONE ? 'p' : 'i');
> > +
> > +	/*
> > +	 * Enable all Virtual Channels
> > +	 *
> > +	 * NOTE: I'ts not possible to get individual format for each
> 
> I'ts -> It's
> 
> > +	 *       source virtual channel. Once this is possible in V4L2
> > +	 *       it should be used here.
> > +	 */
> > +	for (i = 0; i < 4; i++) {
> > +
> 
> Remove empty line.
> 
> > +		format = rcar_csi2_code_to_fmt(mf->code);
> > +		if (!format) {
> > +			dev_err(priv->dev, "Unsupported media bus format: %d\n",
> > +				mf->code);
> > +			return -EINVAL;
> > +		}
> > +
> > +		tmp = VCDT_SEL_VC(i) | VCDT_VCDTN_EN | VCDT_SEL_DTN_ON |
> > +			VCDT_SEL_DT(format->datatype);
> > +
> > +		/* Store in correct reg and offset */
> > +		if (i < 2)
> > +			vcdt |= tmp << ((i % 2) * 16);
> > +		else
> > +			vcdt2 |= tmp << ((i % 2) * 16);
> > +	}
> > +
> > +	switch (priv->lanes) {
> > +	case 1:
> > +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_0;
> > +		break;
> > +	case 2:
> > +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_1 | PHYCNT_ENABLE_0;
> > +		break;
> > +	case 4:
> > +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_3 | PHYCNT_ENABLE_2 |
> > +			PHYCNT_ENABLE_1 | PHYCNT_ENABLE_0;
> > +		break;
> > +	default:
> > +		return -EINVAL;
> > +	}
> > +
> > +	ret = rcar_csi2_calc_phypll(priv, source, mf, &phypll);
> > +	if (ret)
> > +		return ret;
> > +
> > +	/* Init */
> > +	rcar_csi2_write(priv, TREF_REG, TREF_TREF);
> > +	rcar_csi2_reset(priv);
> > +	rcar_csi2_write(priv, PHTC_REG, 0);
> > +
> > +	/* Configure */
> > +	rcar_csi2_write(priv, FLD_REG, FLD_FLD_NUM(2) | FLD_FLD_EN4 |
> > +			FLD_FLD_EN3 | FLD_FLD_EN2 | FLD_FLD_EN);
> > +	rcar_csi2_write(priv, VCDT_REG, vcdt);
> > +	rcar_csi2_write(priv, VCDT2_REG, vcdt2);
> > +	/* Lanes are zero indexed */
> > +	rcar_csi2_write(priv, LSWAP_REG,
> > +			LSWAP_L0SEL(priv->lane_swap[0] - 1) |
> > +			LSWAP_L1SEL(priv->lane_swap[1] - 1) |
> > +			LSWAP_L2SEL(priv->lane_swap[2] - 1) |
> > +			LSWAP_L3SEL(priv->lane_swap[3] - 1));
> > +
> > +	/* Start */
> > +	rcar_csi2_write(priv, PHYPLL_REG, phypll);
> > +	rcar_csi2_write(priv, PHYCNT_REG, phycnt);
> > +	rcar_csi2_write(priv, LINKCNT_REG, LINKCNT_MONITOR_EN |
> > +			LINKCNT_REG_MONI_PACT_EN | LINKCNT_ICLK_NONSTOP);
> > +	rcar_csi2_write(priv, PHYCNT_REG, phycnt | PHYCNT_SHUTDOWNZ);
> > +	rcar_csi2_write(priv, PHYCNT_REG, phycnt | PHYCNT_SHUTDOWNZ |
> > +			PHYCNT_RSTZ);
> > +
> > +	return rcar_csi2_wait_phy_start(priv);
> > +}
> > +
> > +static void rcar_csi2_stop(struct rcar_csi2 *priv)
> > +{
> > +	rcar_csi2_write(priv, PHYCNT_REG, 0);
> > +
> > +	rcar_csi2_reset(priv);
> > +}
> > +
> > +static int rcar_csi2_sd_info(struct rcar_csi2 *priv, struct v4l2_subdev **sd)
> > +{
> > +	struct media_pad *pad;
> > +
> > +	pad = media_entity_remote_pad(&priv->pads[RCAR_CSI2_SINK]);
> > +	if (!pad) {
> > +		dev_err(priv->dev, "Could not find remote pad\n");
> > +		return -ENODEV;
> > +	}
> > +
> > +	*sd = media_entity_to_v4l2_subdev(pad->entity);
> > +	if (!*sd) {
> > +		dev_err(priv->dev, "Could not find remote subdevice\n");
> > +		return -ENODEV;
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_s_stream(struct v4l2_subdev *sd, int enable)
> > +{
> > +	struct rcar_csi2 *priv = sd_to_csi2(sd);
> > +	struct v4l2_subdev *nextsd;
> > +	int ret;
> > +
> > +	mutex_lock(&priv->lock);
> > +
> > +	ret = rcar_csi2_sd_info(priv, &nextsd);
> > +	if (ret)
> > +		goto out;
> > +
> > +	priv->stream_count += enable ? 1 : -1;
> > +
> > +	if (enable && priv->stream_count == 1) {
> > +		ret =  rcar_csi2_start(priv);
> > +		if (ret)
> > +			goto out;
> > +		ret = v4l2_subdev_call(nextsd, video, s_stream, 1);
> > +
> > +	} else if (!enable && !priv->stream_count) {
> > +		rcar_csi2_stop(priv);
> > +		ret = v4l2_subdev_call(nextsd, video, s_stream, 0);
> > +	}
> > +out:
> > +	mutex_unlock(&priv->lock);
> > +
> > +	return ret;
> > +}
> > +
> > +static int rcar_csi2_s_power(struct v4l2_subdev *sd, int on)
> > +{
> > +	struct rcar_csi2 *priv = sd_to_csi2(sd);
> > +
> > +	if (on)
> > +		pm_runtime_get_sync(priv->dev);
> > +	else
> > +		pm_runtime_put(priv->dev);
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_set_pad_format(struct v4l2_subdev *sd,
> > +				    struct v4l2_subdev_pad_config *cfg,
> > +				    struct v4l2_subdev_format *format)
> > +{
> > +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> > +
> > +	if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE)
> > +		priv->mf = format->format;
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_get_pad_format(struct v4l2_subdev *sd,
> > +				    struct v4l2_subdev_pad_config *cfg,
> > +				    struct v4l2_subdev_format *format)
> > +{
> > +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> > +
> > +	format->format = priv->mf;
> > +
> > +	return 0;
> > +}
> > +
> > +static const struct v4l2_subdev_video_ops rcar_csi2_video_ops = {
> > +	.s_stream = rcar_csi2_s_stream,
> > +};
> > +
> > +static const struct v4l2_subdev_core_ops rcar_csi2_subdev_core_ops = {
> > +	.s_power = rcar_csi2_s_power,
> > +};
> > +
> > +static const struct v4l2_subdev_pad_ops rcar_csi2_pad_ops = {
> > +	.set_fmt = rcar_csi2_set_pad_format,
> > +	.get_fmt = rcar_csi2_get_pad_format,
> > +};
> > +
> > +static const struct v4l2_subdev_ops rcar_csi2_subdev_ops = {
> > +	.video	= &rcar_csi2_video_ops,
> > +	.core	= &rcar_csi2_subdev_core_ops,
> > +	.pad	= &rcar_csi2_pad_ops,
> > +};
> > +
> > +/* -----------------------------------------------------------------------------
> > + * Async and registered of subdevices and links
> > + */
> > +
> > +#define notifier_to_priv(n) container_of(n, struct rcar_csi2, notifier)
> > +
> > +static int rcar_csi2_notify_complete(struct v4l2_async_notifier *notifier)
> > +{
> > +	struct rcar_csi2 *priv = notifier_to_priv(notifier);
> > +	int ret;
> > +
> > +	ret = v4l2_device_register_subdev_nodes(priv->subdev.v4l2_dev);
> > +	if (ret) {
> > +		dev_err(priv->dev, "Failed to register subdev nodes\n");
> > +		return ret;
> > +	}
> > +
> > +	return media_create_pad_link(&priv->remote.subdev->entity,
> > +				     priv->remote.source_pad,
> > +				     &priv->subdev.entity, 0,
> > +				     MEDIA_LNK_FL_ENABLED |
> > +				     MEDIA_LNK_FL_IMMUTABLE);
> 
> Shouldn't the link be created before the register subdev nodes are registered?
> 
> Usually that's done at the very end after everything else has been configured
> correctly.

I think you are correct here as well, will look into it for next 
version.

> 
> > +}
> > +
> > +static int rcar_csi2_notify_bound(struct v4l2_async_notifier *notifier,
> > +				   struct v4l2_subdev *subdev,
> > +				   struct v4l2_async_subdev *asd)
> > +{
> > +	struct rcar_csi2 *priv = notifier_to_priv(notifier);
> > +	int ret;
> > +
> > +	v4l2_set_subdev_hostdata(subdev, priv);
> > +
> > +	ret = media_entity_pad_from_fwnode(&subdev->entity,
> > +					   priv->remote.fwnode,
> > +					   MEDIA_PAD_FL_SOURCE,
> > +					   &priv->remote.source_pad);
> > +	if (ret) {
> > +		dev_err(priv->dev, "Failed to find pad for %s\n",
> > +			subdev->name);
> > +		return ret;
> > +	}
> > +
> > +	dev_dbg(priv->dev, "Bound %s pad: %d\n", subdev->name,
> > +		priv->remote.source_pad);
> > +	priv->remote.subdev = subdev;
> > +
> > +	return 0;
> > +}
> > +static void rcar_csi2_notify_unbind(struct v4l2_async_notifier *notifier,
> > +				     struct v4l2_subdev *subdev,
> > +				     struct v4l2_async_subdev *asd)
> > +{
> > +	struct rcar_csi2 *priv = notifier_to_priv(notifier);
> > +
> > +	dev_dbg(priv->dev, "Unbind %s\n", subdev->name);
> > +	priv->remote.subdev = NULL;
> > +}
> > +
> > +static int rcar_csi2_registered(struct v4l2_subdev *sd)
> > +{
> > +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> > +	struct v4l2_async_subdev **subdevs = NULL;
> > +	int ret;
> > +
> > +	subdevs = devm_kzalloc(priv->dev, sizeof(*subdevs), GFP_KERNEL);
> > +	if (subdevs == NULL)
> > +		return -ENOMEM;
> > +
> > +	subdevs[0] = &priv->remote.asd;
> > +
> > +	priv->notifier.num_subdevs = 1;
> > +	priv->notifier.subdevs = subdevs;
> > +	priv->notifier.bound = rcar_csi2_notify_bound;
> > +	priv->notifier.unbind = rcar_csi2_notify_unbind;
> > +	priv->notifier.complete = rcar_csi2_notify_complete;
> > +
> > +	ret = v4l2_async_subnotifier_register(&priv->subdev, &priv->notifier);
> > +	if (ret < 0) {
> > +		dev_err(priv->dev, "Notifier registration failed\n");
> > +		return ret;
> > +	}
> > +
> > +	return 0;
> > +}
> 
> Hmm, I'm trying to understand this, and I got one question. There are at least
> two complete callbacks: rcar_csi2_notify_complete and the bridge driver's
> complete callback. Am I right that the bridge driver's complete callback is
> called as soon as this function exists (assuming this is the only subdev)?

Yes (at least for the async case).

In v4l2_async_test_notify() calls v4l2_device_register_subdev() which in 
turns calls this registered callback. v4l2_async_test_notify() then go 
on and calls the notifiers complete callback.

In my case I have (in the simplified case) AD7482 -> CSI-2 -> VIN. Where 
VIN is the video device and CSI-2 is the subdevice of VIN while the 
ADV7482 is a subdevice to the CSI-2. In that case the call graph would 
be:

v4l2_async_test_notify()                (From VIN on the CSI-2 subdev)
  v4l2_device_register_subdev()
    sd->internal_ops->registered(sd);   (sd == CSI-2 subdev)
      v4l2_async_subnotifier_register() (CSI-2 notifier for the ADV7482 subdev)
        v4l2_async_test_notify()        (From CSI-2 on the ADV7482) [1]
  notifier->complete(notifier);         (on the notifier from VIN)

> 
> So the bridge driver thinks it is complete when in reality this subdev may
> be waiting on newly registered subdevs?

Yes if the ADV7482 subdevice are not already registered in [1] above the 
VIN complete callback would be called before the complete callback have 
been called on the notifier register from the CSI-2 registered callback.  
Instead that would be called once the ADV7482 calls 
v4l2_async_register_subdev().

> 
> If I am right, then my question is if that is what we want. If I am wrong,
> then what did I miss?

I think that is what we want?

>From the VIN point of view all the subdevices it registered in it's 
notifier have been found and bound right so I think it's correct to call 
the complete callback for that notifier at this point?  If it really 
cared about that all devices be present before it calls it complete 
callback should it not also add all devices to its own notifier list? 

But I do see your point that the VIN really have no way of telling if 
all devices are present and we are ready to start to stream. This 
however will be found out with a -EPIPE error if a stream is tried to be 
started since the CSI-2 driver will fail to verify the pipeline since it 
have no subdevice attached to its source pad. What do you think?

> 
> > +
> > +static void rcar_csi2_unregistered(struct v4l2_subdev *sd)
> > +{
> > +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> > +
> > +	v4l2_async_subnotifier_unregister(&priv->notifier);
> > +}
> > +
> > +static const struct v4l2_subdev_internal_ops rcar_csi2_internal_ops = {
> > +	.registered = rcar_csi2_registered,
> > +	.unregistered = rcar_csi2_unregistered,
> > +};
> > +
> > +static int rcar_csi2_parse_dt_subdevice(struct rcar_csi2 *priv)
> > +{
> > +	struct device_node *remote, *ep;
> > +	struct v4l2_fwnode_endpoint v4l2_ep;
> > +	int ret;
> > +
> > +	ep = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0);
> > +	if (!ep) {
> > +		dev_err(priv->dev, "Not connected to subdevice\n");
> > +		return -EINVAL;
> > +	}
> > +
> > +	ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &v4l2_ep);
> > +	if (ret) {
> > +		dev_err(priv->dev, "Could not parse v4l2 endpoint\n");
> > +		of_node_put(ep);
> > +		return -EINVAL;
> > +	}
> > +
> > +	if (v4l2_ep.bus_type != V4L2_MBUS_CSI2) {
> > +		dev_err(priv->dev, "Unknown media bus type: 0x%x\n",
> > +			v4l2_ep.bus_type);
> > +		of_node_put(ep);
> > +		return -EINVAL;
> > +	}
> > +
> > +	priv->remote.fwnode =
> > +		fwnode_graph_get_remote_endpoint(of_fwnode_handle(ep));
> > +
> > +	remote = of_graph_get_remote_port_parent(ep);
> > +	of_node_put(ep);
> > +	if (!remote) {
> > +		dev_err(priv->dev, "No subdevice found for endpoint '%s'\n",
> > +			of_node_full_name(ep));
> > +		return -EINVAL;
> > +	}
> > +
> > +	priv->remote.asd.match.fwnode.fwnode = of_fwnode_handle(remote);
> > +	priv->remote.asd.match_type = V4L2_ASYNC_MATCH_FWNODE;
> > +
> > +	dev_dbg(priv->dev, "Found '%s'\n", of_node_full_name(remote));
> > +
> > +	return 0;
> > +}
> > +
> > +/* -----------------------------------------------------------------------------
> > + * Platform Device Driver
> > + */
> > +
> > +static const struct of_device_id rcar_csi2_of_table[] = {
> > +	{ .compatible = "renesas,rcar-gen3-csi2" },
> > +	{ },
> > +};
> > +MODULE_DEVICE_TABLE(of, rcar_csi2_of_table);
> > +
> > +static const struct media_entity_operations rcar_csi2_entity_ops = {
> > +	.link_validate = v4l2_subdev_link_validate,
> > +};
> > +
> > +static int rcar_csi2_parse_dt_settings(struct rcar_csi2 *priv)
> > +{
> > +	struct v4l2_fwnode_endpoint v4l2_ep;
> > +	struct device_node *ep;
> > +	unsigned int i;
> > +	int ret;
> > +
> > +	ep = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0);
> > +	if (!ep)
> > +		return -EINVAL;
> > +
> > +	ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &v4l2_ep);
> > +	of_node_put(ep);
> > +	if (ret) {
> > +		dev_err(priv->dev, "Could not parse v4l2 endpoint\n");
> > +		return -EINVAL;
> > +	}
> > +
> > +	if (v4l2_ep.bus_type != V4L2_MBUS_CSI2) {
> > +		dev_err(priv->dev, "Unsupported media bus type for %s\n",
> > +			of_node_full_name(ep));
> > +		return -EINVAL;
> > +	}
> > +
> > +	priv->lanes = v4l2_ep.bus.mipi_csi2.num_data_lanes;
> > +	if (priv->lanes != 1 && priv->lanes != 2 && priv->lanes != 4) {
> > +		dev_err(priv->dev, "Unsupported number of data-lanes: %d\n",
> > +			priv->lanes);
> > +		return -EINVAL;
> > +	}
> > +
> > +	for (i = 0; i < ARRAY_SIZE(priv->lane_swap); i++) {
> > +		priv->lane_swap[i] = i < priv->lanes ?
> > +			v4l2_ep.bus.mipi_csi2.data_lanes[i] : i;
> > +
> > +		/* Check for valid lane number */
> > +		if (priv->lane_swap[i] < 1 || priv->lane_swap[i] > 4) {
> > +			dev_err(priv->dev, "data-lanes must be in 1-4 range\n");
> > +			return -EINVAL;
> > +		}
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_probe_resources(struct rcar_csi2 *priv,
> > +				     struct platform_device *pdev)
> > +{
> > +	struct resource *mem;
> > +	int irq;
> > +
> > +	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > +	if (!mem)
> > +		return -ENODEV;
> > +
> > +	priv->base = devm_ioremap_resource(&pdev->dev, mem);
> > +	if (IS_ERR(priv->base))
> > +		return PTR_ERR(priv->base);
> > +
> > +	irq = platform_get_irq(pdev, 0);
> > +	if (irq < 0)
> > +		return irq;
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_probe(struct platform_device *pdev)
> > +{
> > +	struct rcar_csi2 *priv;
> > +	unsigned int i;
> > +	int ret;
> > +
> > +	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
> > +	if (!priv)
> > +		return -ENOMEM;
> > +
> > +	priv->dev = &pdev->dev;
> > +
> > +	mutex_init(&priv->lock);
> > +	priv->stream_count = 0;
> > +
> > +	ret = rcar_csi2_parse_dt_settings(priv);
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = rcar_csi2_parse_dt_subdevice(priv);
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = rcar_csi2_probe_resources(priv, pdev);
> > +	if (ret) {
> > +		dev_err(priv->dev, "Failed to get resources\n");
> > +		return ret;
> > +	}
> > +
> > +	platform_set_drvdata(pdev, priv);
> > +
> > +	priv->subdev.owner = THIS_MODULE;
> > +	priv->subdev.dev = &pdev->dev;
> > +	v4l2_subdev_init(&priv->subdev, &rcar_csi2_subdev_ops);
> > +	v4l2_set_subdevdata(&priv->subdev, &pdev->dev);
> > +	snprintf(priv->subdev.name, V4L2_SUBDEV_NAME_SIZE, "%s %s",
> > +		 KBUILD_MODNAME, dev_name(&pdev->dev));
> > +	priv->subdev.flags = V4L2_SUBDEV_FL_HAS_DEVNODE;
> > +	priv->subdev.internal_ops = &rcar_csi2_internal_ops;
> > +
> > +	priv->subdev.entity.function = MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER;
> > +	priv->subdev.entity.ops = &rcar_csi2_entity_ops;
> > +
> > +	priv->pads[RCAR_CSI2_SINK].flags = MEDIA_PAD_FL_SINK;
> > +	for (i = RCAR_CSI2_SOURCE_VC0; i < NR_OF_RCAR_CSI2_PAD; i++)
> > +		priv->pads[i].flags = MEDIA_PAD_FL_SOURCE;
> > +
> > +	ret = media_entity_pads_init(&priv->subdev.entity, NR_OF_RCAR_CSI2_PAD,
> > +				     priv->pads);
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = v4l2_async_register_subdev(&priv->subdev);
> > +	if (ret < 0)
> > +		return ret;
> > +
> > +	pm_runtime_enable(&pdev->dev);
> > +
> > +	dev_info(priv->dev, "%d lanes found\n", priv->lanes);
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_remove(struct platform_device *pdev)
> > +{
> > +	struct rcar_csi2 *priv = platform_get_drvdata(pdev);
> > +
> > +	v4l2_async_unregister_subdev(&priv->subdev);
> > +
> > +	pm_runtime_disable(&pdev->dev);
> > +
> > +	return 0;
> > +}
> > +
> > +static struct platform_driver __refdata rcar_csi2_pdrv = {
> > +	.remove	= rcar_csi2_remove,
> > +	.probe	= rcar_csi2_probe,
> > +	.driver	= {
> > +		.name	= "rcar-csi2",
> > +		.of_match_table	= of_match_ptr(rcar_csi2_of_table),
> > +	},
> > +};
> > +
> > +module_platform_driver(rcar_csi2_pdrv);
> > +
> > +MODULE_AUTHOR("Niklas Söderlund <niklas.soderlund@ragnatech.se>");
> > +MODULE_DESCRIPTION("Renesas R-Car MIPI CSI-2 receiver");
> > +MODULE_LICENSE("GPL v2");
> > 
> 
> Regards,
> 
> 	Hans

-- 
Regards,
Niklas Söderlund

Re: [PATCH v7 2/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver driver

[Niklas Söderlund]

Hi Hans,

Thanks for your comments.

On 2017-05-29 13:16:23 +0200, Hans Verkuil wrote:
> On 05/24/2017 02:13 AM, Niklas S�derlund wrote:
> > From: Niklas S�derlund <niklas.soderlund+renesas@ragnatech.se>
> > 
> > A V4L2 driver for Renesas R-Car MIPI CSI-2 receiver. The driver
> > supports the rcar-vin driver on R-Car Gen3 SoCs where separate CSI-2
> > hardware blocks are connected between the video sources and the video
> > grabbers (VIN).
> > 
> > Driver is based on a prototype by Koji Matsuoka in the Renesas BSP.
> > 
> > Signed-off-by: Niklas S�derlund <niklas.soderlund+renesas@ragnatech.se>
> > ---
> >   drivers/media/platform/rcar-vin/Kconfig     |  12 +
> >   drivers/media/platform/rcar-vin/Makefile    |   1 +
> >   drivers/media/platform/rcar-vin/rcar-csi2.c | 867 ++++++++++++++++++++++++++++
> >   3 files changed, 880 insertions(+)
> >   create mode 100644 drivers/media/platform/rcar-vin/rcar-csi2.c
> > 
> > diff --git a/drivers/media/platform/rcar-vin/Kconfig b/drivers/media/platform/rcar-vin/Kconfig
> > index af4c98b44d2e22cb..6875f30c1ae42631 100644
> > --- a/drivers/media/platform/rcar-vin/Kconfig
> > +++ b/drivers/media/platform/rcar-vin/Kconfig
> > @@ -1,3 +1,15 @@
> > +config VIDEO_RCAR_CSI2
> > +	tristate "R-Car MIPI CSI-2 Receiver"
> > +	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && OF
> > +	depends on ARCH_RENESAS || COMPILE_TEST
> > +	select V4L2_FWNODE
> > +	---help---
> > +	  Support for Renesas R-Car MIPI CSI-2 receiver.
> > +	  Supports R-Car Gen3 SoCs.
> > +
> > +	  To compile this driver as a module, choose M here: the
> > +	  module will be called rcar-csi2.
> > +
> >   config VIDEO_RCAR_VIN
> >   	tristate "R-Car Video Input (VIN) Driver"
> >   	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && OF && HAS_DMA && MEDIA_CONTROLLER
> > diff --git a/drivers/media/platform/rcar-vin/Makefile b/drivers/media/platform/rcar-vin/Makefile
> > index 48c5632c21dc060b..5ab803d3e7c1aa57 100644
> > --- a/drivers/media/platform/rcar-vin/Makefile
> > +++ b/drivers/media/platform/rcar-vin/Makefile
> > @@ -1,3 +1,4 @@
> >   rcar-vin-objs = rcar-core.o rcar-dma.o rcar-v4l2.o
> > +obj-$(CONFIG_VIDEO_RCAR_CSI2) += rcar-csi2.o
> >   obj-$(CONFIG_VIDEO_RCAR_VIN) += rcar-vin.o
> > diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
> > new file mode 100644
> > index 0000000000000000..1175f1fe4b139a13
> > --- /dev/null
> > +++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
> > @@ -0,0 +1,867 @@
> > +/*
> > + * Driver for Renesas R-Car MIPI CSI-2 Receiver
> > + *
> > + * Copyright (C) 2017 Renesas Electronics Corp.
> > + *
> > + * This program is free software; you can redistribute  it and/or modify it
> > + * under  the terms of  the GNU General  Public License as published by the
> > + * Free Software Foundation;  either version 2 of the  License, or (at your
> > + * option) any later version.
> > + */
> > +
> > +#include <linux/delay.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/io.h>
> > +#include <linux/module.h>
> > +#include <linux/of.h>
> > +#include <linux/of_device.h>
> > +#include <linux/of_graph.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/pm_runtime.h>
> > +
> > +#include <media/v4l2-ctrls.h>
> > +#include <media/v4l2-device.h>
> > +#include <media/v4l2-fwnode.h>
> > +#include <media/v4l2-mc.h>
> > +#include <media/v4l2-subdev.h>
> > +
> > +/* Register offsets and bits */
> > +
> > +/* Control Timing Select */
> > +#define TREF_REG			0x00
> > +#define TREF_TREF			(1 << 0)
> > +
> > +/* Software Reset */
> > +#define SRST_REG			0x04
> > +#define SRST_SRST			(1 << 0)
> > +
> > +/* PHY Operation Control */
> > +#define PHYCNT_REG			0x08
> > +#define PHYCNT_SHUTDOWNZ		(1 << 17)
> > +#define PHYCNT_RSTZ			(1 << 16)
> > +#define PHYCNT_ENABLECLK		(1 << 4)
> > +#define PHYCNT_ENABLE_3			(1 << 3)
> > +#define PHYCNT_ENABLE_2			(1 << 2)
> > +#define PHYCNT_ENABLE_1			(1 << 1)
> > +#define PHYCNT_ENABLE_0			(1 << 0)
> > +
> > +/* Checksum Control */
> > +#define CHKSUM_REG			0x0c
> > +#define CHKSUM_ECC_EN			(1 << 1)
> > +#define CHKSUM_CRC_EN			(1 << 0)
> > +
> > +/*
> > + * Channel Data Type Select
> > + * VCDT[0-15]:  Channel 1 VCDT[16-31]:  Channel 2
> > + * VCDT2[0-15]: Channel 3 VCDT2[16-31]: Channel 4
> > + */
> > +#define VCDT_REG			0x10
> > +#define VCDT2_REG			0x14
> > +#define VCDT_VCDTN_EN			(1 << 15)
> > +#define VCDT_SEL_VC(n)			(((n) & 0x3) << 8)
> > +#define VCDT_SEL_DTN_ON			(1 << 6)
> > +#define VCDT_SEL_DT(n)			(((n) & 0x3f) << 0)
> > +
> > +/* Frame Data Type Select */
> > +#define FRDT_REG			0x18
> > +
> > +/* Field Detection Control */
> > +#define FLD_REG				0x1c
> > +#define FLD_FLD_NUM(n)			(((n) & 0xff) << 16)
> > +#define FLD_FLD_EN4			(1 << 3)
> > +#define FLD_FLD_EN3			(1 << 2)
> > +#define FLD_FLD_EN2			(1 << 1)
> > +#define FLD_FLD_EN			(1 << 0)
> > +
> > +/* Automatic Standby Control */
> > +#define ASTBY_REG			0x20
> > +
> > +/* Long Data Type Setting 0 */
> > +#define LNGDT0_REG			0x28
> > +
> > +/* Long Data Type Setting 1 */
> > +#define LNGDT1_REG			0x2c
> > +
> > +/* Interrupt Enable */
> > +#define INTEN_REG			0x30
> > +
> > +/* Interrupt Source Mask */
> > +#define INTCLOSE_REG			0x34
> > +
> > +/* Interrupt Status Monitor */
> > +#define INTSTATE_REG			0x38
> > +
> > +/* Interrupt Error Status Monitor */
> > +#define INTERRSTATE_REG			0x3c
> > +
> > +/* Short Packet Data */
> > +#define SHPDAT_REG			0x40
> > +
> > +/* Short Packet Count */
> > +#define SHPCNT_REG			0x44
> > +
> > +/* LINK Operation Control */
> > +#define LINKCNT_REG			0x48
> > +#define LINKCNT_MONITOR_EN		(1 << 31)
> > +#define LINKCNT_REG_MONI_PACT_EN	(1 << 25)
> > +#define LINKCNT_ICLK_NONSTOP		(1 << 24)
> > +
> > +/* Lane Swap */
> > +#define LSWAP_REG			0x4c
> > +#define LSWAP_L3SEL(n)			(((n) & 0x3) << 6)
> > +#define LSWAP_L2SEL(n)			(((n) & 0x3) << 4)
> > +#define LSWAP_L1SEL(n)			(((n) & 0x3) << 2)
> > +#define LSWAP_L0SEL(n)			(((n) & 0x3) << 0)
> > +
> > +/* PHY Test Interface Clear */
> > +#define PHTC_REG			0x58
> > +#define PHTC_TESTCLR			(1 << 0)
> > +
> > +/* PHY Frequency Control */
> > +#define PHYPLL_REG			0x68
> > +#define PHYPLL_HSFREQRANGE(n)		((n) << 16)
> > +
> > +struct phypll_hsfreqrange {
> > +	unsigned int	mbps;
> > +	unsigned char	reg;
> > +};
> > +
> > +static const struct phypll_hsfreqrange phypll_hsfreqrange_map[] = {
> > +	{ .mbps =   80,	.reg = 0x00 },
> > +	{ .mbps =   90,	.reg = 0x10 },
> > +	{ .mbps =  100,	.reg = 0x20 },
> > +	{ .mbps =  110,	.reg = 0x30 },
> > +	{ .mbps =  120,	.reg = 0x01 },
> > +	{ .mbps =  130,	.reg = 0x11 },
> > +	{ .mbps =  140,	.reg = 0x21 },
> > +	{ .mbps =  150,	.reg = 0x31 },
> > +	{ .mbps =  160,	.reg = 0x02 },
> > +	{ .mbps =  170,	.reg = 0x12 },
> > +	{ .mbps =  180,	.reg = 0x22 },
> > +	{ .mbps =  190,	.reg = 0x32 },
> > +	{ .mbps =  205,	.reg = 0x03 },
> > +	{ .mbps =  220,	.reg = 0x13 },
> > +	{ .mbps =  235,	.reg = 0x23 },
> > +	{ .mbps =  250,	.reg = 0x33 },
> > +	{ .mbps =  275,	.reg = 0x04 },
> > +	{ .mbps =  300,	.reg = 0x14 },
> > +	{ .mbps =  325,	.reg = 0x05 },
> > +	{ .mbps =  350,	.reg = 0x15 },
> > +	{ .mbps =  400,	.reg = 0x25 },
> > +	{ .mbps =  450,	.reg = 0x06 },
> > +	{ .mbps =  500,	.reg = 0x16 },
> > +	{ .mbps =  550,	.reg = 0x07 },
> > +	{ .mbps =  600,	.reg = 0x17 },
> > +	{ .mbps =  650,	.reg = 0x08 },
> > +	{ .mbps =  700,	.reg = 0x18 },
> > +	{ .mbps =  750,	.reg = 0x09 },
> > +	{ .mbps =  800,	.reg = 0x19 },
> > +	{ .mbps =  850,	.reg = 0x29 },
> > +	{ .mbps =  900,	.reg = 0x39 },
> > +	{ .mbps =  950,	.reg = 0x0A },
> > +	{ .mbps = 1000,	.reg = 0x1A },
> > +	{ .mbps = 1050,	.reg = 0x2A },
> > +	{ .mbps = 1100,	.reg = 0x3A },
> > +	{ .mbps = 1150,	.reg = 0x0B },
> > +	{ .mbps = 1200,	.reg = 0x1B },
> > +	{ .mbps = 1250,	.reg = 0x2B },
> > +	{ .mbps = 1300,	.reg = 0x3B },
> > +	{ .mbps = 1350,	.reg = 0x0C },
> > +	{ .mbps = 1400,	.reg = 0x1C },
> > +	{ .mbps = 1450,	.reg = 0x2C },
> > +	{ .mbps = 1500,	.reg = 0x3C },
> > +	/* guard */
> > +	{ .mbps =   0,	.reg = 0x00 },
> > +};
> > +
> > +/* PHY ESC Error Monitor */
> > +#define PHEERM_REG			0x74
> > +
> > +/* PHY Clock Lane Monitor */
> > +#define PHCLM_REG			0x78
> > +
> > +/* PHY Data Lane Monitor */
> > +#define PHDLM_REG			0x7c
> > +
> > +struct rcar_csi2_format {
> > +	unsigned int code;
> > +	unsigned int datatype;
> > +	unsigned int bpp;
> > +};
> > +
> > +static const struct rcar_csi2_format rcar_csi2_formats[] = {
> > +	{ .code = MEDIA_BUS_FMT_RGB888_1X24,	.datatype = 0x24, .bpp = 24},
> > +	{ .code = MEDIA_BUS_FMT_UYVY8_1X16,	.datatype = 0x1e, .bpp = 8 },
> > +	{ .code = MEDIA_BUS_FMT_UYVY8_2X8,	.datatype = 0x1e, .bpp = 8 },
> > +	{ .code = MEDIA_BUS_FMT_YUYV10_2X10,	.datatype = 0x1e, .bpp = 8 },
> > +};
> > +
> > +static const struct rcar_csi2_format *rcar_csi2_code_to_fmt(unsigned int code)
> > +{
> > +	int i;
> > +
> > +	for (i = 0; i < ARRAY_SIZE(rcar_csi2_formats); i++)
> > +		if (rcar_csi2_formats[i].code == code)
> > +			return rcar_csi2_formats + i;
> > +	return NULL;
> > +}
> > +
> > +enum rcar_csi2_pads {
> > +	RCAR_CSI2_SINK,
> > +	RCAR_CSI2_SOURCE_VC0,
> > +	RCAR_CSI2_SOURCE_VC1,
> > +	RCAR_CSI2_SOURCE_VC2,
> > +	RCAR_CSI2_SOURCE_VC3,
> > +	NR_OF_RCAR_CSI2_PAD,
> > +};
> > +
> > +struct rcar_csi2 {
> > +	struct device *dev;
> > +	void __iomem *base;
> > +
> > +	unsigned short lanes;
> > +	unsigned char lane_swap[4];
> > +
> > +	struct v4l2_subdev subdev;
> > +	struct media_pad pads[NR_OF_RCAR_CSI2_PAD];
> > +
> > +	struct v4l2_mbus_framefmt mf;
> > +
> > +	struct mutex lock;
> > +	int stream_count;
> > +
> > +	struct v4l2_async_notifier notifier;
> > +	struct {
> > +		struct v4l2_async_subdev asd;
> > +		struct v4l2_subdev *subdev;
> > +		struct fwnode_handle *fwnode;
> > +		unsigned int source_pad;
> > +	} remote;
> > +};
> > +
> > +static inline struct rcar_csi2 *sd_to_csi2(struct v4l2_subdev *sd)
> > +{
> > +	return container_of(sd, struct rcar_csi2, subdev);
> > +}
> > +
> > +static u32 rcar_csi2_read(struct rcar_csi2 *priv, unsigned int reg)
> > +{
> > +	return ioread32(priv->base + reg);
> > +}
> > +
> > +static void rcar_csi2_write(struct rcar_csi2 *priv, unsigned int reg, u32 data)
> > +{
> > +	iowrite32(data, priv->base + reg);
> > +}
> > +
> > +static void rcar_csi2_reset(struct rcar_csi2 *priv)
> > +{
> > +	rcar_csi2_write(priv, SRST_REG, SRST_SRST);
> > +	rcar_csi2_write(priv, SRST_REG, 0);
> > +}
> > +
> > +static int rcar_csi2_wait_phy_start(struct rcar_csi2 *priv)
> > +{
> > +	int timeout;
> > +
> > +	/* Wait for the clock and data lanes to enter LP-11 state. */
> > +	for (timeout = 100; timeout >= 0; timeout--) {
> > +		const u32 lane_mask = (1 << priv->lanes) - 1;
> > +
> > +		if ((rcar_csi2_read(priv, PHCLM_REG) & 1) == 1 &&
> > +		    (rcar_csi2_read(priv, PHDLM_REG) & lane_mask) == lane_mask)
> > +			return 0;
> > +
> > +		msleep(20);
> > +	}
> > +
> > +	dev_err(priv->dev, "Timeout waiting for LP-11 state\n");
> > +
> > +	return -ETIMEDOUT;
> > +}
> > +
> > +static int rcar_csi2_calc_phypll(struct rcar_csi2 *priv,
> > +				 struct v4l2_subdev *source,
> > +				 struct v4l2_mbus_framefmt *mf,
> > +				 u32 *phypll)
> > +{
> > +	const struct phypll_hsfreqrange *hsfreq;
> > +	const struct rcar_csi2_format *format;
> > +	struct v4l2_ext_controls ctrls;
> > +	struct v4l2_ext_control ctrl;
> > +	u64 mbps;
> > +	int ret;
> > +
> > +	memset(&ctrls, 0, sizeof(ctrls));
> > +	memset(&ctrl, 0, sizeof(ctrl));
> > +
> > +	ctrl.id = V4L2_CID_PIXEL_RATE;
> > +
> > +	ctrls.count = 1;
> > +	ctrls.controls = &ctrl;
> > +
> > +	ret = v4l2_g_ext_ctrls(source->ctrl_handler, &ctrls);
> > +	if (ret < 0) {
> > +		dev_err(priv->dev, "no link freq control in subdev %s\n",
> > +			source->name);
> > +		return ret;
> > +	}
> 
> Please use v4l2_ctrl_g_ctrl_int64 instead. v4l2_g_ext_ctrls is not intended to
> be used by drivers.

Thanks will do this for the next version.

> 
> > +
> > +	format = rcar_csi2_code_to_fmt(mf->code);
> > +	if (!format) {
> > +		dev_err(priv->dev, "Unknown format: %d\n", mf->code);
> > +		return -EINVAL;
> > +	}
> > +
> > +	mbps = ctrl.value64 * format->bpp;
> > +	do_div(mbps, priv->lanes * 1000000);
> > +
> > +	for (hsfreq = phypll_hsfreqrange_map; hsfreq->mbps != 0; hsfreq++)
> > +		if (hsfreq->mbps >= mbps)
> > +			break;
> > +
> > +	if (!hsfreq->mbps) {
> > +		dev_err(priv->dev, "Unsupported PHY speed (%llu Mbps)", mbps);
> > +		return -ERANGE;
> > +	}
> > +
> > +	dev_dbg(priv->dev, "PHY HSFREQRANGE requested %llu got %u Mbps\n", mbps,
> > +		hsfreq->mbps);
> > +
> > +	*phypll = PHYPLL_HSFREQRANGE(hsfreq->reg);
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_start(struct rcar_csi2 *priv)
> > +{
> > +	const struct rcar_csi2_format *format;
> > +	struct v4l2_subdev_format fmt;
> > +	struct media_pad *source_pad;
> > +	struct v4l2_subdev *source = NULL;
> > +	struct v4l2_mbus_framefmt *mf = &fmt.format;
> > +	u32 phycnt, phypll, tmp;
> > +	u32 vcdt = 0, vcdt2 = 0;
> > +	unsigned int i;
> > +	int ret;
> > +
> > +	source_pad =
> > +		media_entity_remote_pad(&priv->subdev.entity.pads[RCAR_CSI2_SINK]);
> > +	if (!source_pad) {
> > +		dev_err(priv->dev, "Could not find remote source pad\n");
> > +		return -ENODEV;
> > +	}
> > +
> > +	source = media_entity_to_v4l2_subdev(source_pad->entity);
> > +	if (!source) {
> > +		dev_err(priv->dev, "Could not find remote subdevice\n");
> > +		return -ENODEV;
> > +	}
> > +
> > +	dev_dbg(priv->dev, "Using source %s pad: %u\n", source->name,
> > +		source_pad->index);
> > +
> > +	fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
> > +	fmt.pad = source_pad->index;
> > +	ret = v4l2_subdev_call(source, pad, get_fmt, NULL, &fmt);
> > +	if (ret)
> > +		return ret;
> > +
> > +	dev_dbg(priv->dev, "Input size (%dx%d%c)\n", mf->width,
> > +		mf->height, mf->field == V4L2_FIELD_NONE ? 'p' : 'i');
> > +
> > +	/*
> > +	 * Enable all Virtual Channels
> > +	 *
> > +	 * NOTE: I'ts not possible to get individual format for each
> 
> I'ts -> It's
> 
> > +	 *       source virtual channel. Once this is possible in V4L2
> > +	 *       it should be used here.
> > +	 */
> > +	for (i = 0; i < 4; i++) {
> > +
> 
> Remove empty line.
> 
> > +		format = rcar_csi2_code_to_fmt(mf->code);
> > +		if (!format) {
> > +			dev_err(priv->dev, "Unsupported media bus format: %d\n",
> > +				mf->code);
> > +			return -EINVAL;
> > +		}
> > +
> > +		tmp = VCDT_SEL_VC(i) | VCDT_VCDTN_EN | VCDT_SEL_DTN_ON |
> > +			VCDT_SEL_DT(format->datatype);
> > +
> > +		/* Store in correct reg and offset */
> > +		if (i < 2)
> > +			vcdt |= tmp << ((i % 2) * 16);
> > +		else
> > +			vcdt2 |= tmp << ((i % 2) * 16);
> > +	}
> > +
> > +	switch (priv->lanes) {
> > +	case 1:
> > +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_0;
> > +		break;
> > +	case 2:
> > +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_1 | PHYCNT_ENABLE_0;
> > +		break;
> > +	case 4:
> > +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_3 | PHYCNT_ENABLE_2 |
> > +			PHYCNT_ENABLE_1 | PHYCNT_ENABLE_0;
> > +		break;
> > +	default:
> > +		return -EINVAL;
> > +	}
> > +
> > +	ret = rcar_csi2_calc_phypll(priv, source, mf, &phypll);
> > +	if (ret)
> > +		return ret;
> > +
> > +	/* Init */
> > +	rcar_csi2_write(priv, TREF_REG, TREF_TREF);
> > +	rcar_csi2_reset(priv);
> > +	rcar_csi2_write(priv, PHTC_REG, 0);
> > +
> > +	/* Configure */
> > +	rcar_csi2_write(priv, FLD_REG, FLD_FLD_NUM(2) | FLD_FLD_EN4 |
> > +			FLD_FLD_EN3 | FLD_FLD_EN2 | FLD_FLD_EN);
> > +	rcar_csi2_write(priv, VCDT_REG, vcdt);
> > +	rcar_csi2_write(priv, VCDT2_REG, vcdt2);
> > +	/* Lanes are zero indexed */
> > +	rcar_csi2_write(priv, LSWAP_REG,
> > +			LSWAP_L0SEL(priv->lane_swap[0] - 1) |
> > +			LSWAP_L1SEL(priv->lane_swap[1] - 1) |
> > +			LSWAP_L2SEL(priv->lane_swap[2] - 1) |
> > +			LSWAP_L3SEL(priv->lane_swap[3] - 1));
> > +
> > +	/* Start */
> > +	rcar_csi2_write(priv, PHYPLL_REG, phypll);
> > +	rcar_csi2_write(priv, PHYCNT_REG, phycnt);
> > +	rcar_csi2_write(priv, LINKCNT_REG, LINKCNT_MONITOR_EN |
> > +			LINKCNT_REG_MONI_PACT_EN | LINKCNT_ICLK_NONSTOP);
> > +	rcar_csi2_write(priv, PHYCNT_REG, phycnt | PHYCNT_SHUTDOWNZ);
> > +	rcar_csi2_write(priv, PHYCNT_REG, phycnt | PHYCNT_SHUTDOWNZ |
> > +			PHYCNT_RSTZ);
> > +
> > +	return rcar_csi2_wait_phy_start(priv);
> > +}
> > +
> > +static void rcar_csi2_stop(struct rcar_csi2 *priv)
> > +{
> > +	rcar_csi2_write(priv, PHYCNT_REG, 0);
> > +
> > +	rcar_csi2_reset(priv);
> > +}
> > +
> > +static int rcar_csi2_sd_info(struct rcar_csi2 *priv, struct v4l2_subdev **sd)
> > +{
> > +	struct media_pad *pad;
> > +
> > +	pad = media_entity_remote_pad(&priv->pads[RCAR_CSI2_SINK]);
> > +	if (!pad) {
> > +		dev_err(priv->dev, "Could not find remote pad\n");
> > +		return -ENODEV;
> > +	}
> > +
> > +	*sd = media_entity_to_v4l2_subdev(pad->entity);
> > +	if (!*sd) {
> > +		dev_err(priv->dev, "Could not find remote subdevice\n");
> > +		return -ENODEV;
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_s_stream(struct v4l2_subdev *sd, int enable)
> > +{
> > +	struct rcar_csi2 *priv = sd_to_csi2(sd);
> > +	struct v4l2_subdev *nextsd;
> > +	int ret;
> > +
> > +	mutex_lock(&priv->lock);
> > +
> > +	ret = rcar_csi2_sd_info(priv, &nextsd);
> > +	if (ret)
> > +		goto out;
> > +
> > +	priv->stream_count += enable ? 1 : -1;
> > +
> > +	if (enable && priv->stream_count == 1) {
> > +		ret =  rcar_csi2_start(priv);
> > +		if (ret)
> > +			goto out;
> > +		ret = v4l2_subdev_call(nextsd, video, s_stream, 1);
> > +
> > +	} else if (!enable && !priv->stream_count) {
> > +		rcar_csi2_stop(priv);
> > +		ret = v4l2_subdev_call(nextsd, video, s_stream, 0);
> > +	}
> > +out:
> > +	mutex_unlock(&priv->lock);
> > +
> > +	return ret;
> > +}
> > +
> > +static int rcar_csi2_s_power(struct v4l2_subdev *sd, int on)
> > +{
> > +	struct rcar_csi2 *priv = sd_to_csi2(sd);
> > +
> > +	if (on)
> > +		pm_runtime_get_sync(priv->dev);
> > +	else
> > +		pm_runtime_put(priv->dev);
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_set_pad_format(struct v4l2_subdev *sd,
> > +				    struct v4l2_subdev_pad_config *cfg,
> > +				    struct v4l2_subdev_format *format)
> > +{
> > +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> > +
> > +	if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE)
> > +		priv->mf = format->format;
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_get_pad_format(struct v4l2_subdev *sd,
> > +				    struct v4l2_subdev_pad_config *cfg,
> > +				    struct v4l2_subdev_format *format)
> > +{
> > +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> > +
> > +	format->format = priv->mf;
> > +
> > +	return 0;
> > +}
> > +
> > +static const struct v4l2_subdev_video_ops rcar_csi2_video_ops = {
> > +	.s_stream = rcar_csi2_s_stream,
> > +};
> > +
> > +static const struct v4l2_subdev_core_ops rcar_csi2_subdev_core_ops = {
> > +	.s_power = rcar_csi2_s_power,
> > +};
> > +
> > +static const struct v4l2_subdev_pad_ops rcar_csi2_pad_ops = {
> > +	.set_fmt = rcar_csi2_set_pad_format,
> > +	.get_fmt = rcar_csi2_get_pad_format,
> > +};
> > +
> > +static const struct v4l2_subdev_ops rcar_csi2_subdev_ops = {
> > +	.video	= &rcar_csi2_video_ops,
> > +	.core	= &rcar_csi2_subdev_core_ops,
> > +	.pad	= &rcar_csi2_pad_ops,
> > +};
> > +
> > +/* -----------------------------------------------------------------------------
> > + * Async and registered of subdevices and links
> > + */
> > +
> > +#define notifier_to_priv(n) container_of(n, struct rcar_csi2, notifier)
> > +
> > +static int rcar_csi2_notify_complete(struct v4l2_async_notifier *notifier)
> > +{
> > +	struct rcar_csi2 *priv = notifier_to_priv(notifier);
> > +	int ret;
> > +
> > +	ret = v4l2_device_register_subdev_nodes(priv->subdev.v4l2_dev);
> > +	if (ret) {
> > +		dev_err(priv->dev, "Failed to register subdev nodes\n");
> > +		return ret;
> > +	}
> > +
> > +	return media_create_pad_link(&priv->remote.subdev->entity,
> > +				     priv->remote.source_pad,
> > +				     &priv->subdev.entity, 0,
> > +				     MEDIA_LNK_FL_ENABLED |
> > +				     MEDIA_LNK_FL_IMMUTABLE);
> 
> Shouldn't the link be created before the register subdev nodes are registered?
> 
> Usually that's done at the very end after everything else has been configured
> correctly.

I think you are correct here as well, will look into it for next 
version.

> 
> > +}
> > +
> > +static int rcar_csi2_notify_bound(struct v4l2_async_notifier *notifier,
> > +				   struct v4l2_subdev *subdev,
> > +				   struct v4l2_async_subdev *asd)
> > +{
> > +	struct rcar_csi2 *priv = notifier_to_priv(notifier);
> > +	int ret;
> > +
> > +	v4l2_set_subdev_hostdata(subdev, priv);
> > +
> > +	ret = media_entity_pad_from_fwnode(&subdev->entity,
> > +					   priv->remote.fwnode,
> > +					   MEDIA_PAD_FL_SOURCE,
> > +					   &priv->remote.source_pad);
> > +	if (ret) {
> > +		dev_err(priv->dev, "Failed to find pad for %s\n",
> > +			subdev->name);
> > +		return ret;
> > +	}
> > +
> > +	dev_dbg(priv->dev, "Bound %s pad: %d\n", subdev->name,
> > +		priv->remote.source_pad);
> > +	priv->remote.subdev = subdev;
> > +
> > +	return 0;
> > +}
> > +static void rcar_csi2_notify_unbind(struct v4l2_async_notifier *notifier,
> > +				     struct v4l2_subdev *subdev,
> > +				     struct v4l2_async_subdev *asd)
> > +{
> > +	struct rcar_csi2 *priv = notifier_to_priv(notifier);
> > +
> > +	dev_dbg(priv->dev, "Unbind %s\n", subdev->name);
> > +	priv->remote.subdev = NULL;
> > +}
> > +
> > +static int rcar_csi2_registered(struct v4l2_subdev *sd)
> > +{
> > +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> > +	struct v4l2_async_subdev **subdevs = NULL;
> > +	int ret;
> > +
> > +	subdevs = devm_kzalloc(priv->dev, sizeof(*subdevs), GFP_KERNEL);
> > +	if (subdevs == NULL)
> > +		return -ENOMEM;
> > +
> > +	subdevs[0] = &priv->remote.asd;
> > +
> > +	priv->notifier.num_subdevs = 1;
> > +	priv->notifier.subdevs = subdevs;
> > +	priv->notifier.bound = rcar_csi2_notify_bound;
> > +	priv->notifier.unbind = rcar_csi2_notify_unbind;
> > +	priv->notifier.complete = rcar_csi2_notify_complete;
> > +
> > +	ret = v4l2_async_subnotifier_register(&priv->subdev, &priv->notifier);
> > +	if (ret < 0) {
> > +		dev_err(priv->dev, "Notifier registration failed\n");
> > +		return ret;
> > +	}
> > +
> > +	return 0;
> > +}
> 
> Hmm, I'm trying to understand this, and I got one question. There are at least
> two complete callbacks: rcar_csi2_notify_complete and the bridge driver's
> complete callback. Am I right that the bridge driver's complete callback is
> called as soon as this function exists (assuming this is the only subdev)?

Yes (at least for the async case).

In v4l2_async_test_notify() calls v4l2_device_register_subdev() which in 
turns calls this registered callback. v4l2_async_test_notify() then go 
on and calls the notifiers complete callback.

In my case I have (in the simplified case) AD7482 -> CSI-2 -> VIN. Where 
VIN is the video device and CSI-2 is the subdevice of VIN while the 
ADV7482 is a subdevice to the CSI-2. In that case the call graph would 
be:

v4l2_async_test_notify()                (From VIN on the CSI-2 subdev)
  v4l2_device_register_subdev()
    sd->internal_ops->registered(sd);   (sd == CSI-2 subdev)
      v4l2_async_subnotifier_register() (CSI-2 notifier for the ADV7482 subdev)
        v4l2_async_test_notify()        (From CSI-2 on the ADV7482) [1]
  notifier->complete(notifier);         (on the notifier from VIN)

> 
> So the bridge driver thinks it is complete when in reality this subdev may
> be waiting on newly registered subdevs?

Yes if the ADV7482 subdevice are not already registered in [1] above the 
VIN complete callback would be called before the complete callback have 
been called on the notifier register from the CSI-2 registered callback.  
Instead that would be called once the ADV7482 calls 
v4l2_async_register_subdev().

> 
> If I am right, then my question is if that is what we want. If I am wrong,
> then what did I miss?

I think that is what we want?

>From the VIN point of view all the subdevices it registered in it's 
notifier have been found and bound right so I think it's correct to call 
the complete callback for that notifier at this point?  If it really 
cared about that all devices be present before it calls it complete 
callback should it not also add all devices to its own notifier list? 

But I do see your point that the VIN really have no way of telling if 
all devices are present and we are ready to start to stream. This 
however will be found out with a -EPIPE error if a stream is tried to be 
started since the CSI-2 driver will fail to verify the pipeline since it 
have no subdevice attached to its source pad. What do you think?

> 
> > +
> > +static void rcar_csi2_unregistered(struct v4l2_subdev *sd)
> > +{
> > +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> > +
> > +	v4l2_async_subnotifier_unregister(&priv->notifier);
> > +}
> > +
> > +static const struct v4l2_subdev_internal_ops rcar_csi2_internal_ops = {
> > +	.registered = rcar_csi2_registered,
> > +	.unregistered = rcar_csi2_unregistered,
> > +};
> > +
> > +static int rcar_csi2_parse_dt_subdevice(struct rcar_csi2 *priv)
> > +{
> > +	struct device_node *remote, *ep;
> > +	struct v4l2_fwnode_endpoint v4l2_ep;
> > +	int ret;
> > +
> > +	ep = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0);
> > +	if (!ep) {
> > +		dev_err(priv->dev, "Not connected to subdevice\n");
> > +		return -EINVAL;
> > +	}
> > +
> > +	ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &v4l2_ep);
> > +	if (ret) {
> > +		dev_err(priv->dev, "Could not parse v4l2 endpoint\n");
> > +		of_node_put(ep);
> > +		return -EINVAL;
> > +	}
> > +
> > +	if (v4l2_ep.bus_type != V4L2_MBUS_CSI2) {
> > +		dev_err(priv->dev, "Unknown media bus type: 0x%x\n",
> > +			v4l2_ep.bus_type);
> > +		of_node_put(ep);
> > +		return -EINVAL;
> > +	}
> > +
> > +	priv->remote.fwnode =
> > +		fwnode_graph_get_remote_endpoint(of_fwnode_handle(ep));
> > +
> > +	remote = of_graph_get_remote_port_parent(ep);
> > +	of_node_put(ep);
> > +	if (!remote) {
> > +		dev_err(priv->dev, "No subdevice found for endpoint '%s'\n",
> > +			of_node_full_name(ep));
> > +		return -EINVAL;
> > +	}
> > +
> > +	priv->remote.asd.match.fwnode.fwnode = of_fwnode_handle(remote);
> > +	priv->remote.asd.match_type = V4L2_ASYNC_MATCH_FWNODE;
> > +
> > +	dev_dbg(priv->dev, "Found '%s'\n", of_node_full_name(remote));
> > +
> > +	return 0;
> > +}
> > +
> > +/* -----------------------------------------------------------------------------
> > + * Platform Device Driver
> > + */
> > +
> > +static const struct of_device_id rcar_csi2_of_table[] = {
> > +	{ .compatible = "renesas,rcar-gen3-csi2" },
> > +	{ },
> > +};
> > +MODULE_DEVICE_TABLE(of, rcar_csi2_of_table);
> > +
> > +static const struct media_entity_operations rcar_csi2_entity_ops = {
> > +	.link_validate = v4l2_subdev_link_validate,
> > +};
> > +
> > +static int rcar_csi2_parse_dt_settings(struct rcar_csi2 *priv)
> > +{
> > +	struct v4l2_fwnode_endpoint v4l2_ep;
> > +	struct device_node *ep;
> > +	unsigned int i;
> > +	int ret;
> > +
> > +	ep = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0);
> > +	if (!ep)
> > +		return -EINVAL;
> > +
> > +	ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &v4l2_ep);
> > +	of_node_put(ep);
> > +	if (ret) {
> > +		dev_err(priv->dev, "Could not parse v4l2 endpoint\n");
> > +		return -EINVAL;
> > +	}
> > +
> > +	if (v4l2_ep.bus_type != V4L2_MBUS_CSI2) {
> > +		dev_err(priv->dev, "Unsupported media bus type for %s\n",
> > +			of_node_full_name(ep));
> > +		return -EINVAL;
> > +	}
> > +
> > +	priv->lanes = v4l2_ep.bus.mipi_csi2.num_data_lanes;
> > +	if (priv->lanes != 1 && priv->lanes != 2 && priv->lanes != 4) {
> > +		dev_err(priv->dev, "Unsupported number of data-lanes: %d\n",
> > +			priv->lanes);
> > +		return -EINVAL;
> > +	}
> > +
> > +	for (i = 0; i < ARRAY_SIZE(priv->lane_swap); i++) {
> > +		priv->lane_swap[i] = i < priv->lanes ?
> > +			v4l2_ep.bus.mipi_csi2.data_lanes[i] : i;
> > +
> > +		/* Check for valid lane number */
> > +		if (priv->lane_swap[i] < 1 || priv->lane_swap[i] > 4) {
> > +			dev_err(priv->dev, "data-lanes must be in 1-4 range\n");
> > +			return -EINVAL;
> > +		}
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_probe_resources(struct rcar_csi2 *priv,
> > +				     struct platform_device *pdev)
> > +{
> > +	struct resource *mem;
> > +	int irq;
> > +
> > +	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > +	if (!mem)
> > +		return -ENODEV;
> > +
> > +	priv->base = devm_ioremap_resource(&pdev->dev, mem);
> > +	if (IS_ERR(priv->base))
> > +		return PTR_ERR(priv->base);
> > +
> > +	irq = platform_get_irq(pdev, 0);
> > +	if (irq < 0)
> > +		return irq;
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_probe(struct platform_device *pdev)
> > +{
> > +	struct rcar_csi2 *priv;
> > +	unsigned int i;
> > +	int ret;
> > +
> > +	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
> > +	if (!priv)
> > +		return -ENOMEM;
> > +
> > +	priv->dev = &pdev->dev;
> > +
> > +	mutex_init(&priv->lock);
> > +	priv->stream_count = 0;
> > +
> > +	ret = rcar_csi2_parse_dt_settings(priv);
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = rcar_csi2_parse_dt_subdevice(priv);
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = rcar_csi2_probe_resources(priv, pdev);
> > +	if (ret) {
> > +		dev_err(priv->dev, "Failed to get resources\n");
> > +		return ret;
> > +	}
> > +
> > +	platform_set_drvdata(pdev, priv);
> > +
> > +	priv->subdev.owner = THIS_MODULE;
> > +	priv->subdev.dev = &pdev->dev;
> > +	v4l2_subdev_init(&priv->subdev, &rcar_csi2_subdev_ops);
> > +	v4l2_set_subdevdata(&priv->subdev, &pdev->dev);
> > +	snprintf(priv->subdev.name, V4L2_SUBDEV_NAME_SIZE, "%s %s",
> > +		 KBUILD_MODNAME, dev_name(&pdev->dev));
> > +	priv->subdev.flags = V4L2_SUBDEV_FL_HAS_DEVNODE;
> > +	priv->subdev.internal_ops = &rcar_csi2_internal_ops;
> > +
> > +	priv->subdev.entity.function = MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER;
> > +	priv->subdev.entity.ops = &rcar_csi2_entity_ops;
> > +
> > +	priv->pads[RCAR_CSI2_SINK].flags = MEDIA_PAD_FL_SINK;
> > +	for (i = RCAR_CSI2_SOURCE_VC0; i < NR_OF_RCAR_CSI2_PAD; i++)
> > +		priv->pads[i].flags = MEDIA_PAD_FL_SOURCE;
> > +
> > +	ret = media_entity_pads_init(&priv->subdev.entity, NR_OF_RCAR_CSI2_PAD,
> > +				     priv->pads);
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = v4l2_async_register_subdev(&priv->subdev);
> > +	if (ret < 0)
> > +		return ret;
> > +
> > +	pm_runtime_enable(&pdev->dev);
> > +
> > +	dev_info(priv->dev, "%d lanes found\n", priv->lanes);
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_remove(struct platform_device *pdev)
> > +{
> > +	struct rcar_csi2 *priv = platform_get_drvdata(pdev);
> > +
> > +	v4l2_async_unregister_subdev(&priv->subdev);
> > +
> > +	pm_runtime_disable(&pdev->dev);
> > +
> > +	return 0;
> > +}
> > +
> > +static struct platform_driver __refdata rcar_csi2_pdrv = {
> > +	.remove	= rcar_csi2_remove,
> > +	.probe	= rcar_csi2_probe,
> > +	.driver	= {
> > +		.name	= "rcar-csi2",
> > +		.of_match_table	= of_match_ptr(rcar_csi2_of_table),
> > +	},
> > +};
> > +
> > +module_platform_driver(rcar_csi2_pdrv);
> > +
> > +MODULE_AUTHOR("Niklas S�derlund <niklas.soderlund@ragnatech.se>");
> > +MODULE_DESCRIPTION("Renesas R-Car MIPI CSI-2 receiver");
> > +MODULE_LICENSE("GPL v2");
> > 
> 
> Regards,
> 
> 	Hans

-- 
Regards,
Niklas S�derlund

Re: [PATCH v7 2/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver driver

[Hans Verkuil]

On 06/12/2017 04:48 PM, Niklas Söderlund wrote:
> Hi Hans,
> 
> Thanks for your comments.
> 
> On 2017-05-29 13:16:23 +0200, Hans Verkuil wrote:
>> On 05/24/2017 02:13 AM, Niklas Söderlund wrote:
>>> From: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
>>>
>>> A V4L2 driver for Renesas R-Car MIPI CSI-2 receiver. The driver
>>> supports the rcar-vin driver on R-Car Gen3 SoCs where separate CSI-2
>>> hardware blocks are connected between the video sources and the video
>>> grabbers (VIN).
>>>
>>> Driver is based on a prototype by Koji Matsuoka in the Renesas BSP.
>>>
>>> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
>>> ---
>>>    drivers/media/platform/rcar-vin/Kconfig     |  12 +
>>>    drivers/media/platform/rcar-vin/Makefile    |   1 +
>>>    drivers/media/platform/rcar-vin/rcar-csi2.c | 867 ++++++++++++++++++++++++++++
>>>    3 files changed, 880 insertions(+)
>>>    create mode 100644 drivers/media/platform/rcar-vin/rcar-csi2.c
>>>

>>> +static int rcar_csi2_registered(struct v4l2_subdev *sd)
>>> +{
>>> +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
>>> +	struct v4l2_async_subdev **subdevs = NULL;
>>> +	int ret;
>>> +
>>> +	subdevs = devm_kzalloc(priv->dev, sizeof(*subdevs), GFP_KERNEL);
>>> +	if (subdevs == NULL)
>>> +		return -ENOMEM;
>>> +
>>> +	subdevs[0] = &priv->remote.asd;
>>> +
>>> +	priv->notifier.num_subdevs = 1;
>>> +	priv->notifier.subdevs = subdevs;
>>> +	priv->notifier.bound = rcar_csi2_notify_bound;
>>> +	priv->notifier.unbind = rcar_csi2_notify_unbind;
>>> +	priv->notifier.complete = rcar_csi2_notify_complete;
>>> +
>>> +	ret = v4l2_async_subnotifier_register(&priv->subdev, &priv->notifier);
>>> +	if (ret < 0) {
>>> +		dev_err(priv->dev, "Notifier registration failed\n");
>>> +		return ret;
>>> +	}
>>> +
>>> +	return 0;
>>> +}
>>
>> Hmm, I'm trying to understand this, and I got one question. There are at least
>> two complete callbacks: rcar_csi2_notify_complete and the bridge driver's
>> complete callback. Am I right that the bridge driver's complete callback is
>> called as soon as this function exists (assuming this is the only subdev)?
> 
> Yes (at least for the async case).
> 
> In v4l2_async_test_notify() calls v4l2_device_register_subdev() which in
> turns calls this registered callback. v4l2_async_test_notify() then go
> on and calls the notifiers complete callback.
> 
> In my case I have (in the simplified case) AD7482 -> CSI-2 -> VIN. Where
> VIN is the video device and CSI-2 is the subdevice of VIN while the
> ADV7482 is a subdevice to the CSI-2. In that case the call graph would
> be:
> 
> v4l2_async_test_notify()                (From VIN on the CSI-2 subdev)
>    v4l2_device_register_subdev()
>      sd->internal_ops->registered(sd);   (sd == CSI-2 subdev)
>        v4l2_async_subnotifier_register() (CSI-2 notifier for the ADV7482 subdev)
>          v4l2_async_test_notify()        (From CSI-2 on the ADV7482) [1]
>    notifier->complete(notifier);         (on the notifier from VIN)
> 
>>
>> So the bridge driver thinks it is complete when in reality this subdev may
>> be waiting on newly registered subdevs?
> 
> Yes if the ADV7482 subdevice are not already registered in [1] above the
> VIN complete callback would be called before the complete callback have
> been called on the notifier register from the CSI-2 registered callback.
> Instead that would be called once the ADV7482 calls
> v4l2_async_register_subdev().
> 
>>
>> If I am right, then my question is if that is what we want. If I am wrong,
>> then what did I miss?
> 
> I think that is what we want?
> 
>  From the VIN point of view all the subdevices it registered in it's
> notifier have been found and bound right so I think it's correct to call
> the complete callback for that notifier at this point?  If it really
> cared about that all devices be present before it calls it complete
> callback should it not also add all devices to its own notifier list?
> 
> But I do see your point that the VIN really have no way of telling if
> all devices are present and we are ready to start to stream. This
> however will be found out with a -EPIPE error if a stream is tried to be
> started since the CSI-2 driver will fail to verify the pipeline since it
> have no subdevice attached to its source pad. What do you think?

I think this is a bad idea. From the point of view of the application you
expect that once the device nodes appear they will also *work*. In this
case it might not work because one piece is still missing. So applications
would have to know that if they get -EPIPE, then if they wait for a few
seconds it might suddenly work because the last component was finally
loaded. That's IMHO not acceptable and will drive application developers
crazy.

In the example above the CSI-2 subdev can't tell VIN that it is complete
when it is still waiting for the ADV7482. Because it *isn't* complete.

It is also unexpected: if A depends on B and B depends on C and D, then
you expect that B won't tell A that is it ready unless C and D are both
loaded.

I was planning to merge this patch today: https://patchwork.linuxtv.org/patch/41834/

But I've decided to hold off on it for a bit in case changes are needed
to solve this particular issue. I think it is better to add that patch
as part of this driver's patch series.

Regards,

	Hans

Re: [PATCH v7 2/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver driver

[Niklas Söderlund]

Hi Hans,

Thanks for your feedback.

On 2017-06-19 13:44:22 +0200, Hans Verkuil wrote:
> On 06/12/2017 04:48 PM, Niklas Söderlund wrote:
> > Hi Hans,
> > 
> > Thanks for your comments.
> > 
> > On 2017-05-29 13:16:23 +0200, Hans Verkuil wrote:
> > > On 05/24/2017 02:13 AM, Niklas Söderlund wrote:
> > > > From: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> > > > 
> > > > A V4L2 driver for Renesas R-Car MIPI CSI-2 receiver. The driver
> > > > supports the rcar-vin driver on R-Car Gen3 SoCs where separate CSI-2
> > > > hardware blocks are connected between the video sources and the video
> > > > grabbers (VIN).
> > > > 
> > > > Driver is based on a prototype by Koji Matsuoka in the Renesas BSP.
> > > > 
> > > > Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> > > > ---
> > > >    drivers/media/platform/rcar-vin/Kconfig     |  12 +
> > > >    drivers/media/platform/rcar-vin/Makefile    |   1 +
> > > >    drivers/media/platform/rcar-vin/rcar-csi2.c | 867 ++++++++++++++++++++++++++++
> > > >    3 files changed, 880 insertions(+)
> > > >    create mode 100644 drivers/media/platform/rcar-vin/rcar-csi2.c
> > > > 
> 
> > > > +static int rcar_csi2_registered(struct v4l2_subdev *sd)
> > > > +{
> > > > +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> > > > +	struct v4l2_async_subdev **subdevs = NULL;
> > > > +	int ret;
> > > > +
> > > > +	subdevs = devm_kzalloc(priv->dev, sizeof(*subdevs), GFP_KERNEL);
> > > > +	if (subdevs == NULL)
> > > > +		return -ENOMEM;
> > > > +
> > > > +	subdevs[0] = &priv->remote.asd;
> > > > +
> > > > +	priv->notifier.num_subdevs = 1;
> > > > +	priv->notifier.subdevs = subdevs;
> > > > +	priv->notifier.bound = rcar_csi2_notify_bound;
> > > > +	priv->notifier.unbind = rcar_csi2_notify_unbind;
> > > > +	priv->notifier.complete = rcar_csi2_notify_complete;
> > > > +
> > > > +	ret = v4l2_async_subnotifier_register(&priv->subdev, &priv->notifier);
> > > > +	if (ret < 0) {
> > > > +		dev_err(priv->dev, "Notifier registration failed\n");
> > > > +		return ret;
> > > > +	}
> > > > +
> > > > +	return 0;
> > > > +}
> > > 
> > > Hmm, I'm trying to understand this, and I got one question. There are at least
> > > two complete callbacks: rcar_csi2_notify_complete and the bridge driver's
> > > complete callback. Am I right that the bridge driver's complete callback is
> > > called as soon as this function exists (assuming this is the only subdev)?
> > 
> > Yes (at least for the async case).
> > 
> > In v4l2_async_test_notify() calls v4l2_device_register_subdev() which in
> > turns calls this registered callback. v4l2_async_test_notify() then go
> > on and calls the notifiers complete callback.
> > 
> > In my case I have (in the simplified case) AD7482 -> CSI-2 -> VIN. Where
> > VIN is the video device and CSI-2 is the subdevice of VIN while the
> > ADV7482 is a subdevice to the CSI-2. In that case the call graph would
> > be:
> > 
> > v4l2_async_test_notify()                (From VIN on the CSI-2 subdev)
> >    v4l2_device_register_subdev()
> >      sd->internal_ops->registered(sd);   (sd == CSI-2 subdev)
> >        v4l2_async_subnotifier_register() (CSI-2 notifier for the ADV7482 subdev)
> >          v4l2_async_test_notify()        (From CSI-2 on the ADV7482) [1]
> >    notifier->complete(notifier);         (on the notifier from VIN)
> > 
> > > 
> > > So the bridge driver thinks it is complete when in reality this subdev may
> > > be waiting on newly registered subdevs?
> > 
> > Yes if the ADV7482 subdevice are not already registered in [1] above the
> > VIN complete callback would be called before the complete callback have
> > been called on the notifier register from the CSI-2 registered callback.
> > Instead that would be called once the ADV7482 calls
> > v4l2_async_register_subdev().
> > 
> > > 
> > > If I am right, then my question is if that is what we want. If I am wrong,
> > > then what did I miss?
> > 
> > I think that is what we want?
> > 
> >  From the VIN point of view all the subdevices it registered in it's
> > notifier have been found and bound right so I think it's correct to call
> > the complete callback for that notifier at this point?  If it really
> > cared about that all devices be present before it calls it complete
> > callback should it not also add all devices to its own notifier list?
> > 
> > But I do see your point that the VIN really have no way of telling if
> > all devices are present and we are ready to start to stream. This
> > however will be found out with a -EPIPE error if a stream is tried to be
> > started since the CSI-2 driver will fail to verify the pipeline since it
> > have no subdevice attached to its source pad. What do you think?
> 
> I think this is a bad idea. From the point of view of the application you
> expect that once the device nodes appear they will also *work*. In this
> case it might not work because one piece is still missing. So applications
> would have to know that if they get -EPIPE, then if they wait for a few
> seconds it might suddenly work because the last component was finally
> loaded. That's IMHO not acceptable and will drive application developers
> crazy.
> 
> In the example above the CSI-2 subdev can't tell VIN that it is complete
> when it is still waiting for the ADV7482. Because it *isn't* complete.
> 
> It is also unexpected: if A depends on B and B depends on C and D, then
> you expect that B won't tell A that is it ready unless C and D are both
> loaded.

You are not alone, I have received additional feedback which also did 
not like this idea. So I be happy to try and find a way to sort this 
out.

> 
> I was planning to merge this patch today: https://patchwork.linuxtv.org/patch/41834/
> 
> But I've decided to hold off on it for a bit in case changes are needed
> to solve this particular issue. I think it is better to add that patch
> as part of this driver's patch series.

I think it was a good call to hold of this patch. I have been presented 
with an alternative idea from Laurent on how one could get incremental 
async feature using a single notifier hence solving the dependency 
problem. I will try to implement this idea and include it as a patch in 
the next version of this series.

> 
> Regards,
> 
> 	Hans

-- 
Regards,
Niklas Söderlund

Re: [PATCH v7 2/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver driver

[Niklas Söderlund]

Hi Hans,

Thanks for your feedback.

On 2017-06-19 13:44:22 +0200, Hans Verkuil wrote:
> On 06/12/2017 04:48 PM, Niklas S�derlund wrote:
> > Hi Hans,
> > 
> > Thanks for your comments.
> > 
> > On 2017-05-29 13:16:23 +0200, Hans Verkuil wrote:
> > > On 05/24/2017 02:13 AM, Niklas S�derlund wrote:
> > > > From: Niklas S�derlund <niklas.soderlund+renesas@ragnatech.se>
> > > > 
> > > > A V4L2 driver for Renesas R-Car MIPI CSI-2 receiver. The driver
> > > > supports the rcar-vin driver on R-Car Gen3 SoCs where separate CSI-2
> > > > hardware blocks are connected between the video sources and the video
> > > > grabbers (VIN).
> > > > 
> > > > Driver is based on a prototype by Koji Matsuoka in the Renesas BSP.
> > > > 
> > > > Signed-off-by: Niklas S�derlund <niklas.soderlund+renesas@ragnatech.se>
> > > > ---
> > > >    drivers/media/platform/rcar-vin/Kconfig     |  12 +
> > > >    drivers/media/platform/rcar-vin/Makefile    |   1 +
> > > >    drivers/media/platform/rcar-vin/rcar-csi2.c | 867 ++++++++++++++++++++++++++++
> > > >    3 files changed, 880 insertions(+)
> > > >    create mode 100644 drivers/media/platform/rcar-vin/rcar-csi2.c
> > > > 
> 
> > > > +static int rcar_csi2_registered(struct v4l2_subdev *sd)
> > > > +{
> > > > +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> > > > +	struct v4l2_async_subdev **subdevs = NULL;
> > > > +	int ret;
> > > > +
> > > > +	subdevs = devm_kzalloc(priv->dev, sizeof(*subdevs), GFP_KERNEL);
> > > > +	if (subdevs == NULL)
> > > > +		return -ENOMEM;
> > > > +
> > > > +	subdevs[0] = &priv->remote.asd;
> > > > +
> > > > +	priv->notifier.num_subdevs = 1;
> > > > +	priv->notifier.subdevs = subdevs;
> > > > +	priv->notifier.bound = rcar_csi2_notify_bound;
> > > > +	priv->notifier.unbind = rcar_csi2_notify_unbind;
> > > > +	priv->notifier.complete = rcar_csi2_notify_complete;
> > > > +
> > > > +	ret = v4l2_async_subnotifier_register(&priv->subdev, &priv->notifier);
> > > > +	if (ret < 0) {
> > > > +		dev_err(priv->dev, "Notifier registration failed\n");
> > > > +		return ret;
> > > > +	}
> > > > +
> > > > +	return 0;
> > > > +}
> > > 
> > > Hmm, I'm trying to understand this, and I got one question. There are at least
> > > two complete callbacks: rcar_csi2_notify_complete and the bridge driver's
> > > complete callback. Am I right that the bridge driver's complete callback is
> > > called as soon as this function exists (assuming this is the only subdev)?
> > 
> > Yes (at least for the async case).
> > 
> > In v4l2_async_test_notify() calls v4l2_device_register_subdev() which in
> > turns calls this registered callback. v4l2_async_test_notify() then go
> > on and calls the notifiers complete callback.
> > 
> > In my case I have (in the simplified case) AD7482 -> CSI-2 -> VIN. Where
> > VIN is the video device and CSI-2 is the subdevice of VIN while the
> > ADV7482 is a subdevice to the CSI-2. In that case the call graph would
> > be:
> > 
> > v4l2_async_test_notify()                (From VIN on the CSI-2 subdev)
> >    v4l2_device_register_subdev()
> >      sd->internal_ops->registered(sd);   (sd == CSI-2 subdev)
> >        v4l2_async_subnotifier_register() (CSI-2 notifier for the ADV7482 subdev)
> >          v4l2_async_test_notify()        (From CSI-2 on the ADV7482) [1]
> >    notifier->complete(notifier);         (on the notifier from VIN)
> > 
> > > 
> > > So the bridge driver thinks it is complete when in reality this subdev may
> > > be waiting on newly registered subdevs?
> > 
> > Yes if the ADV7482 subdevice are not already registered in [1] above the
> > VIN complete callback would be called before the complete callback have
> > been called on the notifier register from the CSI-2 registered callback.
> > Instead that would be called once the ADV7482 calls
> > v4l2_async_register_subdev().
> > 
> > > 
> > > If I am right, then my question is if that is what we want. If I am wrong,
> > > then what did I miss?
> > 
> > I think that is what we want?
> > 
> >  From the VIN point of view all the subdevices it registered in it's
> > notifier have been found and bound right so I think it's correct to call
> > the complete callback for that notifier at this point?  If it really
> > cared about that all devices be present before it calls it complete
> > callback should it not also add all devices to its own notifier list?
> > 
> > But I do see your point that the VIN really have no way of telling if
> > all devices are present and we are ready to start to stream. This
> > however will be found out with a -EPIPE error if a stream is tried to be
> > started since the CSI-2 driver will fail to verify the pipeline since it
> > have no subdevice attached to its source pad. What do you think?
> 
> I think this is a bad idea. From the point of view of the application you
> expect that once the device nodes appear they will also *work*. In this
> case it might not work because one piece is still missing. So applications
> would have to know that if they get -EPIPE, then if they wait for a few
> seconds it might suddenly work because the last component was finally
> loaded. That's IMHO not acceptable and will drive application developers
> crazy.
> 
> In the example above the CSI-2 subdev can't tell VIN that it is complete
> when it is still waiting for the ADV7482. Because it *isn't* complete.
> 
> It is also unexpected: if A depends on B and B depends on C and D, then
> you expect that B won't tell A that is it ready unless C and D are both
> loaded.

You are not alone, I have received additional feedback which also did 
not like this idea. So I be happy to try and find a way to sort this 
out.

> 
> I was planning to merge this patch today: https://patchwork.linuxtv.org/patch/41834/
> 
> But I've decided to hold off on it for a bit in case changes are needed
> to solve this particular issue. I think it is better to add that patch
> as part of this driver's patch series.

I think it was a good call to hold of this patch. I have been presented 
with an alternative idea from Laurent on how one could get incremental 
async feature using a single notifier hence solving the dependency 
problem. I will try to implement this idea and include it as a patch in 
the next version of this series.

> 
> Regards,
> 
> 	Hans

-- 
Regards,
Niklas S�derlund

Re: [PATCH v7 2/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver driver

[Sakari Ailus]

Hi Hans and Niklas,

On Mon, Jun 19, 2017 at 01:44:22PM +0200, Hans Verkuil wrote:
> On 06/12/2017 04:48 PM, Niklas Söderlund wrote:
> > Hi Hans,
> > 
> > Thanks for your comments.
> > 
> > On 2017-05-29 13:16:23 +0200, Hans Verkuil wrote:
> > > On 05/24/2017 02:13 AM, Niklas Söderlund wrote:
> > > > From: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> > > > 
> > > > A V4L2 driver for Renesas R-Car MIPI CSI-2 receiver. The driver
> > > > supports the rcar-vin driver on R-Car Gen3 SoCs where separate CSI-2
> > > > hardware blocks are connected between the video sources and the video
> > > > grabbers (VIN).
> > > > 
> > > > Driver is based on a prototype by Koji Matsuoka in the Renesas BSP.
> > > > 
> > > > Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> > > > ---
> > > >    drivers/media/platform/rcar-vin/Kconfig     |  12 +
> > > >    drivers/media/platform/rcar-vin/Makefile    |   1 +
> > > >    drivers/media/platform/rcar-vin/rcar-csi2.c | 867 ++++++++++++++++++++++++++++
> > > >    3 files changed, 880 insertions(+)
> > > >    create mode 100644 drivers/media/platform/rcar-vin/rcar-csi2.c
> > > > 
> 
> > > > +static int rcar_csi2_registered(struct v4l2_subdev *sd)
> > > > +{
> > > > +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> > > > +	struct v4l2_async_subdev **subdevs = NULL;
> > > > +	int ret;
> > > > +
> > > > +	subdevs = devm_kzalloc(priv->dev, sizeof(*subdevs), GFP_KERNEL);
> > > > +	if (subdevs == NULL)
> > > > +		return -ENOMEM;
> > > > +
> > > > +	subdevs[0] = &priv->remote.asd;
> > > > +
> > > > +	priv->notifier.num_subdevs = 1;
> > > > +	priv->notifier.subdevs = subdevs;
> > > > +	priv->notifier.bound = rcar_csi2_notify_bound;
> > > > +	priv->notifier.unbind = rcar_csi2_notify_unbind;
> > > > +	priv->notifier.complete = rcar_csi2_notify_complete;
> > > > +
> > > > +	ret = v4l2_async_subnotifier_register(&priv->subdev, &priv->notifier);
> > > > +	if (ret < 0) {
> > > > +		dev_err(priv->dev, "Notifier registration failed\n");
> > > > +		return ret;
> > > > +	}
> > > > +
> > > > +	return 0;
> > > > +}
> > > 
> > > Hmm, I'm trying to understand this, and I got one question. There are at least
> > > two complete callbacks: rcar_csi2_notify_complete and the bridge driver's
> > > complete callback. Am I right that the bridge driver's complete callback is
> > > called as soon as this function exists (assuming this is the only subdev)?
> > 
> > Yes (at least for the async case).
> > 
> > In v4l2_async_test_notify() calls v4l2_device_register_subdev() which in
> > turns calls this registered callback. v4l2_async_test_notify() then go
> > on and calls the notifiers complete callback.
> > 
> > In my case I have (in the simplified case) AD7482 -> CSI-2 -> VIN. Where
> > VIN is the video device and CSI-2 is the subdevice of VIN while the
> > ADV7482 is a subdevice to the CSI-2. In that case the call graph would
> > be:
> > 
> > v4l2_async_test_notify()                (From VIN on the CSI-2 subdev)
> >    v4l2_device_register_subdev()
> >      sd->internal_ops->registered(sd);   (sd == CSI-2 subdev)
> >        v4l2_async_subnotifier_register() (CSI-2 notifier for the ADV7482 subdev)
> >          v4l2_async_test_notify()        (From CSI-2 on the ADV7482) [1]
> >    notifier->complete(notifier);         (on the notifier from VIN)
> > 
> > > 
> > > So the bridge driver thinks it is complete when in reality this subdev may
> > > be waiting on newly registered subdevs?
> > 
> > Yes if the ADV7482 subdevice are not already registered in [1] above the
> > VIN complete callback would be called before the complete callback have
> > been called on the notifier register from the CSI-2 registered callback.
> > Instead that would be called once the ADV7482 calls
> > v4l2_async_register_subdev().
> > 
> > > 
> > > If I am right, then my question is if that is what we want. If I am wrong,
> > > then what did I miss?
> > 
> > I think that is what we want?
> > 
> >  From the VIN point of view all the subdevices it registered in it's
> > notifier have been found and bound right so I think it's correct to call
> > the complete callback for that notifier at this point?  If it really
> > cared about that all devices be present before it calls it complete
> > callback should it not also add all devices to its own notifier list?
> > 
> > But I do see your point that the VIN really have no way of telling if
> > all devices are present and we are ready to start to stream. This
> > however will be found out with a -EPIPE error if a stream is tried to be
> > started since the CSI-2 driver will fail to verify the pipeline since it
> > have no subdevice attached to its source pad. What do you think?
> 
> I think this is a bad idea. From the point of view of the application you
> expect that once the device nodes appear they will also *work*. In this
> case it might not work because one piece is still missing. So applications
> would have to know that if they get -EPIPE, then if they wait for a few
> seconds it might suddenly work because the last component was finally
> loaded. That's IMHO not acceptable and will drive application developers
> crazy.

Typically modules are loaded at system bootup, so there's not much chance
of this happening. The user can also detect this from the fact that there
are sub-devices that have pads without links. The MUST_CONNECT pad flag
should be set on such pads in any case: this is actually how the user could
detect the situation.

But then to why I replied to your e-mail, which is that there are other
problems as well. Such as the complete callback itself.

Imagine a system with a single ISP and multiple cameras. Or don't even
imagine one, just take an example from what we'll already have: even
omap3isp supports multiple cameras. The Intel CIO2 device will support
multiple cameras, too.

Each of the cameras can be used independently, but right now a fault in
probing any of the sensors (or other components in the system for that
matter, such as soon supposedly lens, flash or EEPROM devices) will render
all the cameras unusable. It'd be still quite importtant to be able to use
cameras that actually work, even if one of them does not. This is simply a
question of reliability.

The current implementation is that the initialisation of all the related
devices is required to be completed until any device nodes are registered.
This as itself is a part of the problem problem.

How that can be solved is by registering the device nodes of sub-devices
when the sub-devices are registered rather than at the time when all of
them are registered. This will have the effect of making partial device
states visible to the user space during driver probing.

I'd like to claim that it is not knowable whether a device the probing of
which has failed is going to come up in a fraction of a second or is not
going to come up during system uptime. -EPROBE_DEFER probably means that
the device will be around but there's no guarantee about it either, whereas
another error could be possibly fixed e.g. by the user.

Besides, the device nodes are even currently not created at the same
moment; they are rather created within a small window of time during which
the user will have access to the device nodes already created --- which do
not (yet) represent the complete device.

-- 
Kind regards,

Sakari Ailus
e-mail: sakari.ailus@iki.fi	XMPP: sailus@retiisi.org.uk

Re: [PATCH v7 2/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver driver

[Sakari Ailus]

Hi Hans and Niklas,

On Mon, Jun 19, 2017 at 01:44:22PM +0200, Hans Verkuil wrote:
> On 06/12/2017 04:48 PM, Niklas S�derlund wrote:
> > Hi Hans,
> > 
> > Thanks for your comments.
> > 
> > On 2017-05-29 13:16:23 +0200, Hans Verkuil wrote:
> > > On 05/24/2017 02:13 AM, Niklas S�derlund wrote:
> > > > From: Niklas S�derlund <niklas.soderlund+renesas@ragnatech.se>
> > > > 
> > > > A V4L2 driver for Renesas R-Car MIPI CSI-2 receiver. The driver
> > > > supports the rcar-vin driver on R-Car Gen3 SoCs where separate CSI-2
> > > > hardware blocks are connected between the video sources and the video
> > > > grabbers (VIN).
> > > > 
> > > > Driver is based on a prototype by Koji Matsuoka in the Renesas BSP.
> > > > 
> > > > Signed-off-by: Niklas S�derlund <niklas.soderlund+renesas@ragnatech.se>
> > > > ---
> > > >    drivers/media/platform/rcar-vin/Kconfig     |  12 +
> > > >    drivers/media/platform/rcar-vin/Makefile    |   1 +
> > > >    drivers/media/platform/rcar-vin/rcar-csi2.c | 867 ++++++++++++++++++++++++++++
> > > >    3 files changed, 880 insertions(+)
> > > >    create mode 100644 drivers/media/platform/rcar-vin/rcar-csi2.c
> > > > 
> 
> > > > +static int rcar_csi2_registered(struct v4l2_subdev *sd)
> > > > +{
> > > > +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> > > > +	struct v4l2_async_subdev **subdevs = NULL;
> > > > +	int ret;
> > > > +
> > > > +	subdevs = devm_kzalloc(priv->dev, sizeof(*subdevs), GFP_KERNEL);
> > > > +	if (subdevs == NULL)
> > > > +		return -ENOMEM;
> > > > +
> > > > +	subdevs[0] = &priv->remote.asd;
> > > > +
> > > > +	priv->notifier.num_subdevs = 1;
> > > > +	priv->notifier.subdevs = subdevs;
> > > > +	priv->notifier.bound = rcar_csi2_notify_bound;
> > > > +	priv->notifier.unbind = rcar_csi2_notify_unbind;
> > > > +	priv->notifier.complete = rcar_csi2_notify_complete;
> > > > +
> > > > +	ret = v4l2_async_subnotifier_register(&priv->subdev, &priv->notifier);
> > > > +	if (ret < 0) {
> > > > +		dev_err(priv->dev, "Notifier registration failed\n");
> > > > +		return ret;
> > > > +	}
> > > > +
> > > > +	return 0;
> > > > +}
> > > 
> > > Hmm, I'm trying to understand this, and I got one question. There are at least
> > > two complete callbacks: rcar_csi2_notify_complete and the bridge driver's
> > > complete callback. Am I right that the bridge driver's complete callback is
> > > called as soon as this function exists (assuming this is the only subdev)?
> > 
> > Yes (at least for the async case).
> > 
> > In v4l2_async_test_notify() calls v4l2_device_register_subdev() which in
> > turns calls this registered callback. v4l2_async_test_notify() then go
> > on and calls the notifiers complete callback.
> > 
> > In my case I have (in the simplified case) AD7482 -> CSI-2 -> VIN. Where
> > VIN is the video device and CSI-2 is the subdevice of VIN while the
> > ADV7482 is a subdevice to the CSI-2. In that case the call graph would
> > be:
> > 
> > v4l2_async_test_notify()                (From VIN on the CSI-2 subdev)
> >    v4l2_device_register_subdev()
> >      sd->internal_ops->registered(sd);   (sd == CSI-2 subdev)
> >        v4l2_async_subnotifier_register() (CSI-2 notifier for the ADV7482 subdev)
> >          v4l2_async_test_notify()        (From CSI-2 on the ADV7482) [1]
> >    notifier->complete(notifier);         (on the notifier from VIN)
> > 
> > > 
> > > So the bridge driver thinks it is complete when in reality this subdev may
> > > be waiting on newly registered subdevs?
> > 
> > Yes if the ADV7482 subdevice are not already registered in [1] above the
> > VIN complete callback would be called before the complete callback have
> > been called on the notifier register from the CSI-2 registered callback.
> > Instead that would be called once the ADV7482 calls
> > v4l2_async_register_subdev().
> > 
> > > 
> > > If I am right, then my question is if that is what we want. If I am wrong,
> > > then what did I miss?
> > 
> > I think that is what we want?
> > 
> >  From the VIN point of view all the subdevices it registered in it's
> > notifier have been found and bound right so I think it's correct to call
> > the complete callback for that notifier at this point?  If it really
> > cared about that all devices be present before it calls it complete
> > callback should it not also add all devices to its own notifier list?
> > 
> > But I do see your point that the VIN really have no way of telling if
> > all devices are present and we are ready to start to stream. This
> > however will be found out with a -EPIPE error if a stream is tried to be
> > started since the CSI-2 driver will fail to verify the pipeline since it
> > have no subdevice attached to its source pad. What do you think?
> 
> I think this is a bad idea. From the point of view of the application you
> expect that once the device nodes appear they will also *work*. In this
> case it might not work because one piece is still missing. So applications
> would have to know that if they get -EPIPE, then if they wait for a few
> seconds it might suddenly work because the last component was finally
> loaded. That's IMHO not acceptable and will drive application developers
> crazy.

Typically modules are loaded at system bootup, so there's not much chance
of this happening. The user can also detect this from the fact that there
are sub-devices that have pads without links. The MUST_CONNECT pad flag
should be set on such pads in any case: this is actually how the user could
detect the situation.

But then to why I replied to your e-mail, which is that there are other
problems as well. Such as the complete callback itself.

Imagine a system with a single ISP and multiple cameras. Or don't even
imagine one, just take an example from what we'll already have: even
omap3isp supports multiple cameras. The Intel CIO2 device will support
multiple cameras, too.

Each of the cameras can be used independently, but right now a fault in
probing any of the sensors (or other components in the system for that
matter, such as soon supposedly lens, flash or EEPROM devices) will render
all the cameras unusable. It'd be still quite importtant to be able to use
cameras that actually work, even if one of them does not. This is simply a
question of reliability.

The current implementation is that the initialisation of all the related
devices is required to be completed until any device nodes are registered.
This as itself is a part of the problem problem.

How that can be solved is by registering the device nodes of sub-devices
when the sub-devices are registered rather than at the time when all of
them are registered. This will have the effect of making partial device
states visible to the user space during driver probing.

I'd like to claim that it is not knowable whether a device the probing of
which has failed is going to come up in a fraction of a second or is not
going to come up during system uptime. -EPROBE_DEFER probably means that
the device will be around but there's no guarantee about it either, whereas
another error could be possibly fixed e.g. by the user.

Besides, the device nodes are even currently not created at the same
moment; they are rather created within a small window of time during which
the user will have access to the device nodes already created --- which do
not (yet) represent the complete device.

-- 
Kind regards,

Sakari Ailus
e-mail: sakari.ailus@iki.fi	XMPP: sailus@retiisi.org.uk

Re: [PATCH v7 2/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver driver

[Sakari Ailus]

Hi Niklas,

A few comments below.

On Wed, May 24, 2017 at 02:13:53AM +0200, Niklas Söderlund wrote:
> From: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> 
> A V4L2 driver for Renesas R-Car MIPI CSI-2 receiver. The driver
> supports the rcar-vin driver on R-Car Gen3 SoCs where separate CSI-2
> hardware blocks are connected between the video sources and the video
> grabbers (VIN).
> 
> Driver is based on a prototype by Koji Matsuoka in the Renesas BSP.
> 
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> ---
>  drivers/media/platform/rcar-vin/Kconfig     |  12 +
>  drivers/media/platform/rcar-vin/Makefile    |   1 +
>  drivers/media/platform/rcar-vin/rcar-csi2.c | 867 ++++++++++++++++++++++++++++
>  3 files changed, 880 insertions(+)
>  create mode 100644 drivers/media/platform/rcar-vin/rcar-csi2.c
> 
> diff --git a/drivers/media/platform/rcar-vin/Kconfig b/drivers/media/platform/rcar-vin/Kconfig
> index af4c98b44d2e22cb..6875f30c1ae42631 100644
> --- a/drivers/media/platform/rcar-vin/Kconfig
> +++ b/drivers/media/platform/rcar-vin/Kconfig
> @@ -1,3 +1,15 @@
> +config VIDEO_RCAR_CSI2
> +	tristate "R-Car MIPI CSI-2 Receiver"
> +	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && OF
> +	depends on ARCH_RENESAS || COMPILE_TEST
> +	select V4L2_FWNODE
> +	---help---
> +	  Support for Renesas R-Car MIPI CSI-2 receiver.
> +	  Supports R-Car Gen3 SoCs.
> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called rcar-csi2.
> +
>  config VIDEO_RCAR_VIN
>  	tristate "R-Car Video Input (VIN) Driver"
>  	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && OF && HAS_DMA && MEDIA_CONTROLLER
> diff --git a/drivers/media/platform/rcar-vin/Makefile b/drivers/media/platform/rcar-vin/Makefile
> index 48c5632c21dc060b..5ab803d3e7c1aa57 100644
> --- a/drivers/media/platform/rcar-vin/Makefile
> +++ b/drivers/media/platform/rcar-vin/Makefile
> @@ -1,3 +1,4 @@
>  rcar-vin-objs = rcar-core.o rcar-dma.o rcar-v4l2.o
>  
> +obj-$(CONFIG_VIDEO_RCAR_CSI2) += rcar-csi2.o
>  obj-$(CONFIG_VIDEO_RCAR_VIN) += rcar-vin.o
> diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
> new file mode 100644
> index 0000000000000000..1175f1fe4b139a13
> --- /dev/null
> +++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
> @@ -0,0 +1,867 @@
> +/*
> + * Driver for Renesas R-Car MIPI CSI-2 Receiver
> + *
> + * Copyright (C) 2017 Renesas Electronics Corp.
> + *
> + * This program is free software; you can redistribute  it and/or modify it
> + * under  the terms of  the GNU General  Public License as published by the
> + * Free Software Foundation;  either version 2 of the  License, or (at your
> + * option) any later version.
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/of_graph.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +
> +#include <media/v4l2-ctrls.h>
> +#include <media/v4l2-device.h>
> +#include <media/v4l2-fwnode.h>
> +#include <media/v4l2-mc.h>
> +#include <media/v4l2-subdev.h>
> +
> +/* Register offsets and bits */
> +
> +/* Control Timing Select */
> +#define TREF_REG			0x00
> +#define TREF_TREF			(1 << 0)
> +
> +/* Software Reset */
> +#define SRST_REG			0x04
> +#define SRST_SRST			(1 << 0)
> +
> +/* PHY Operation Control */
> +#define PHYCNT_REG			0x08
> +#define PHYCNT_SHUTDOWNZ		(1 << 17)
> +#define PHYCNT_RSTZ			(1 << 16)
> +#define PHYCNT_ENABLECLK		(1 << 4)
> +#define PHYCNT_ENABLE_3			(1 << 3)
> +#define PHYCNT_ENABLE_2			(1 << 2)
> +#define PHYCNT_ENABLE_1			(1 << 1)
> +#define PHYCNT_ENABLE_0			(1 << 0)
> +
> +/* Checksum Control */
> +#define CHKSUM_REG			0x0c
> +#define CHKSUM_ECC_EN			(1 << 1)
> +#define CHKSUM_CRC_EN			(1 << 0)
> +
> +/*
> + * Channel Data Type Select
> + * VCDT[0-15]:  Channel 1 VCDT[16-31]:  Channel 2
> + * VCDT2[0-15]: Channel 3 VCDT2[16-31]: Channel 4
> + */
> +#define VCDT_REG			0x10
> +#define VCDT2_REG			0x14
> +#define VCDT_VCDTN_EN			(1 << 15)
> +#define VCDT_SEL_VC(n)			(((n) & 0x3) << 8)
> +#define VCDT_SEL_DTN_ON			(1 << 6)
> +#define VCDT_SEL_DT(n)			(((n) & 0x3f) << 0)
> +
> +/* Frame Data Type Select */
> +#define FRDT_REG			0x18
> +
> +/* Field Detection Control */
> +#define FLD_REG				0x1c
> +#define FLD_FLD_NUM(n)			(((n) & 0xff) << 16)
> +#define FLD_FLD_EN4			(1 << 3)
> +#define FLD_FLD_EN3			(1 << 2)
> +#define FLD_FLD_EN2			(1 << 1)
> +#define FLD_FLD_EN			(1 << 0)
> +
> +/* Automatic Standby Control */
> +#define ASTBY_REG			0x20
> +
> +/* Long Data Type Setting 0 */
> +#define LNGDT0_REG			0x28
> +
> +/* Long Data Type Setting 1 */
> +#define LNGDT1_REG			0x2c
> +
> +/* Interrupt Enable */
> +#define INTEN_REG			0x30
> +
> +/* Interrupt Source Mask */
> +#define INTCLOSE_REG			0x34
> +
> +/* Interrupt Status Monitor */
> +#define INTSTATE_REG			0x38
> +
> +/* Interrupt Error Status Monitor */
> +#define INTERRSTATE_REG			0x3c
> +
> +/* Short Packet Data */
> +#define SHPDAT_REG			0x40
> +
> +/* Short Packet Count */
> +#define SHPCNT_REG			0x44
> +
> +/* LINK Operation Control */
> +#define LINKCNT_REG			0x48
> +#define LINKCNT_MONITOR_EN		(1 << 31)
> +#define LINKCNT_REG_MONI_PACT_EN	(1 << 25)
> +#define LINKCNT_ICLK_NONSTOP		(1 << 24)
> +
> +/* Lane Swap */
> +#define LSWAP_REG			0x4c
> +#define LSWAP_L3SEL(n)			(((n) & 0x3) << 6)
> +#define LSWAP_L2SEL(n)			(((n) & 0x3) << 4)
> +#define LSWAP_L1SEL(n)			(((n) & 0x3) << 2)
> +#define LSWAP_L0SEL(n)			(((n) & 0x3) << 0)
> +
> +/* PHY Test Interface Clear */
> +#define PHTC_REG			0x58
> +#define PHTC_TESTCLR			(1 << 0)
> +
> +/* PHY Frequency Control */
> +#define PHYPLL_REG			0x68
> +#define PHYPLL_HSFREQRANGE(n)		((n) << 16)
> +
> +struct phypll_hsfreqrange {
> +	unsigned int	mbps;
> +	unsigned char	reg;
> +};
> +
> +static const struct phypll_hsfreqrange phypll_hsfreqrange_map[] = {
> +	{ .mbps =   80,	.reg = 0x00 },
> +	{ .mbps =   90,	.reg = 0x10 },
> +	{ .mbps =  100,	.reg = 0x20 },
> +	{ .mbps =  110,	.reg = 0x30 },
> +	{ .mbps =  120,	.reg = 0x01 },
> +	{ .mbps =  130,	.reg = 0x11 },
> +	{ .mbps =  140,	.reg = 0x21 },
> +	{ .mbps =  150,	.reg = 0x31 },
> +	{ .mbps =  160,	.reg = 0x02 },
> +	{ .mbps =  170,	.reg = 0x12 },
> +	{ .mbps =  180,	.reg = 0x22 },
> +	{ .mbps =  190,	.reg = 0x32 },
> +	{ .mbps =  205,	.reg = 0x03 },
> +	{ .mbps =  220,	.reg = 0x13 },
> +	{ .mbps =  235,	.reg = 0x23 },
> +	{ .mbps =  250,	.reg = 0x33 },
> +	{ .mbps =  275,	.reg = 0x04 },
> +	{ .mbps =  300,	.reg = 0x14 },
> +	{ .mbps =  325,	.reg = 0x05 },
> +	{ .mbps =  350,	.reg = 0x15 },
> +	{ .mbps =  400,	.reg = 0x25 },
> +	{ .mbps =  450,	.reg = 0x06 },
> +	{ .mbps =  500,	.reg = 0x16 },
> +	{ .mbps =  550,	.reg = 0x07 },
> +	{ .mbps =  600,	.reg = 0x17 },
> +	{ .mbps =  650,	.reg = 0x08 },
> +	{ .mbps =  700,	.reg = 0x18 },
> +	{ .mbps =  750,	.reg = 0x09 },
> +	{ .mbps =  800,	.reg = 0x19 },
> +	{ .mbps =  850,	.reg = 0x29 },
> +	{ .mbps =  900,	.reg = 0x39 },
> +	{ .mbps =  950,	.reg = 0x0A },
> +	{ .mbps = 1000,	.reg = 0x1A },
> +	{ .mbps = 1050,	.reg = 0x2A },
> +	{ .mbps = 1100,	.reg = 0x3A },
> +	{ .mbps = 1150,	.reg = 0x0B },
> +	{ .mbps = 1200,	.reg = 0x1B },
> +	{ .mbps = 1250,	.reg = 0x2B },
> +	{ .mbps = 1300,	.reg = 0x3B },
> +	{ .mbps = 1350,	.reg = 0x0C },
> +	{ .mbps = 1400,	.reg = 0x1C },
> +	{ .mbps = 1450,	.reg = 0x2C },
> +	{ .mbps = 1500,	.reg = 0x3C },
> +	/* guard */
> +	{ .mbps =   0,	.reg = 0x00 },
> +};
> +
> +/* PHY ESC Error Monitor */
> +#define PHEERM_REG			0x74
> +
> +/* PHY Clock Lane Monitor */
> +#define PHCLM_REG			0x78
> +
> +/* PHY Data Lane Monitor */
> +#define PHDLM_REG			0x7c
> +
> +struct rcar_csi2_format {
> +	unsigned int code;
> +	unsigned int datatype;
> +	unsigned int bpp;
> +};
> +
> +static const struct rcar_csi2_format rcar_csi2_formats[] = {
> +	{ .code = MEDIA_BUS_FMT_RGB888_1X24,	.datatype = 0x24, .bpp = 24},
> +	{ .code = MEDIA_BUS_FMT_UYVY8_1X16,	.datatype = 0x1e, .bpp = 8 },
> +	{ .code = MEDIA_BUS_FMT_UYVY8_2X8,	.datatype = 0x1e, .bpp = 8 },
> +	{ .code = MEDIA_BUS_FMT_YUYV10_2X10,	.datatype = 0x1e, .bpp = 8 },
> +};
> +
> +static const struct rcar_csi2_format *rcar_csi2_code_to_fmt(unsigned int code)
> +{
> +	int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(rcar_csi2_formats); i++)
> +		if (rcar_csi2_formats[i].code == code)
> +			return rcar_csi2_formats + i;
> +	return NULL;
> +}
> +
> +enum rcar_csi2_pads {
> +	RCAR_CSI2_SINK,
> +	RCAR_CSI2_SOURCE_VC0,
> +	RCAR_CSI2_SOURCE_VC1,
> +	RCAR_CSI2_SOURCE_VC2,
> +	RCAR_CSI2_SOURCE_VC3,
> +	NR_OF_RCAR_CSI2_PAD,
> +};
> +
> +struct rcar_csi2 {
> +	struct device *dev;
> +	void __iomem *base;
> +
> +	unsigned short lanes;
> +	unsigned char lane_swap[4];
> +
> +	struct v4l2_subdev subdev;
> +	struct media_pad pads[NR_OF_RCAR_CSI2_PAD];
> +
> +	struct v4l2_mbus_framefmt mf;
> +
> +	struct mutex lock;
> +	int stream_count;
> +
> +	struct v4l2_async_notifier notifier;
> +	struct {
> +		struct v4l2_async_subdev asd;
> +		struct v4l2_subdev *subdev;
> +		struct fwnode_handle *fwnode;
> +		unsigned int source_pad;
> +	} remote;
> +};
> +
> +static inline struct rcar_csi2 *sd_to_csi2(struct v4l2_subdev *sd)
> +{
> +	return container_of(sd, struct rcar_csi2, subdev);
> +}
> +
> +static u32 rcar_csi2_read(struct rcar_csi2 *priv, unsigned int reg)
> +{
> +	return ioread32(priv->base + reg);
> +}
> +
> +static void rcar_csi2_write(struct rcar_csi2 *priv, unsigned int reg, u32 data)
> +{
> +	iowrite32(data, priv->base + reg);
> +}
> +
> +static void rcar_csi2_reset(struct rcar_csi2 *priv)
> +{
> +	rcar_csi2_write(priv, SRST_REG, SRST_SRST);
> +	rcar_csi2_write(priv, SRST_REG, 0);
> +}
> +
> +static int rcar_csi2_wait_phy_start(struct rcar_csi2 *priv)
> +{
> +	int timeout;
> +
> +	/* Wait for the clock and data lanes to enter LP-11 state. */
> +	for (timeout = 100; timeout >= 0; timeout--) {
> +		const u32 lane_mask = (1 << priv->lanes) - 1;
> +
> +		if ((rcar_csi2_read(priv, PHCLM_REG) & 1) == 1 &&
> +		    (rcar_csi2_read(priv, PHDLM_REG) & lane_mask) == lane_mask)
> +			return 0;
> +
> +		msleep(20);
> +	}
> +
> +	dev_err(priv->dev, "Timeout waiting for LP-11 state\n");
> +
> +	return -ETIMEDOUT;
> +}
> +
> +static int rcar_csi2_calc_phypll(struct rcar_csi2 *priv,
> +				 struct v4l2_subdev *source,
> +				 struct v4l2_mbus_framefmt *mf,
> +				 u32 *phypll)
> +{
> +	const struct phypll_hsfreqrange *hsfreq;
> +	const struct rcar_csi2_format *format;
> +	struct v4l2_ext_controls ctrls;
> +	struct v4l2_ext_control ctrl;
> +	u64 mbps;
> +	int ret;
> +
> +	memset(&ctrls, 0, sizeof(ctrls));
> +	memset(&ctrl, 0, sizeof(ctrl));
> +
> +	ctrl.id = V4L2_CID_PIXEL_RATE;
> +
> +	ctrls.count = 1;
> +	ctrls.controls = &ctrl;
> +
> +	ret = v4l2_g_ext_ctrls(source->ctrl_handler, &ctrls);

v4l2_ctrl_g_ctrl_int64(), please. Or do I miss something?

> +	if (ret < 0) {
> +		dev_err(priv->dev, "no link freq control in subdev %s\n",
> +			source->name);
> +		return ret;
> +	}
> +
> +	format = rcar_csi2_code_to_fmt(mf->code);
> +	if (!format) {
> +		dev_err(priv->dev, "Unknown format: %d\n", mf->code);
> +		return -EINVAL;
> +	}
> +
> +	mbps = ctrl.value64 * format->bpp;
> +	do_div(mbps, priv->lanes * 1000000);
> +
> +	for (hsfreq = phypll_hsfreqrange_map; hsfreq->mbps != 0; hsfreq++)
> +		if (hsfreq->mbps >= mbps)
> +			break;
> +
> +	if (!hsfreq->mbps) {
> +		dev_err(priv->dev, "Unsupported PHY speed (%llu Mbps)", mbps);
> +		return -ERANGE;
> +	}
> +
> +	dev_dbg(priv->dev, "PHY HSFREQRANGE requested %llu got %u Mbps\n", mbps,
> +		hsfreq->mbps);
> +
> +	*phypll = PHYPLL_HSFREQRANGE(hsfreq->reg);
> +
> +	return 0;
> +}
> +
> +static int rcar_csi2_start(struct rcar_csi2 *priv)
> +{
> +	const struct rcar_csi2_format *format;
> +	struct v4l2_subdev_format fmt;
> +	struct media_pad *source_pad;
> +	struct v4l2_subdev *source = NULL;
> +	struct v4l2_mbus_framefmt *mf = &fmt.format;
> +	u32 phycnt, phypll, tmp;
> +	u32 vcdt = 0, vcdt2 = 0;
> +	unsigned int i;
> +	int ret;
> +
> +	source_pad =
> +		media_entity_remote_pad(&priv->subdev.entity.pads[RCAR_CSI2_SINK]);

Over 80 characters per line. I think you could split this up differently.

> +	if (!source_pad) {
> +		dev_err(priv->dev, "Could not find remote source pad\n");
> +		return -ENODEV;
> +	}
> +
> +	source = media_entity_to_v4l2_subdev(source_pad->entity);
> +	if (!source) {
> +		dev_err(priv->dev, "Could not find remote subdevice\n");
> +		return -ENODEV;
> +	}
> +
> +	dev_dbg(priv->dev, "Using source %s pad: %u\n", source->name,
> +		source_pad->index);
> +
> +	fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
> +	fmt.pad = source_pad->index;
> +	ret = v4l2_subdev_call(source, pad, get_fmt, NULL, &fmt);
> +	if (ret)
> +		return ret;
> +
> +	dev_dbg(priv->dev, "Input size (%dx%d%c)\n", mf->width,
> +		mf->height, mf->field == V4L2_FIELD_NONE ? 'p' : 'i');
> +
> +	/*
> +	 * Enable all Virtual Channels
> +	 *
> +	 * NOTE: I'ts not possible to get individual format for each

"It's"

> +	 *       source virtual channel. Once this is possible in V4L2
> +	 *       it should be used here.
> +	 */
> +	for (i = 0; i < 4; i++) {
> +
> +		format = rcar_csi2_code_to_fmt(mf->code);
> +		if (!format) {
> +			dev_err(priv->dev, "Unsupported media bus format: %d\n",
> +				mf->code);
> +			return -EINVAL;
> +		}
> +
> +		tmp = VCDT_SEL_VC(i) | VCDT_VCDTN_EN | VCDT_SEL_DTN_ON |
> +			VCDT_SEL_DT(format->datatype);
> +
> +		/* Store in correct reg and offset */
> +		if (i < 2)
> +			vcdt |= tmp << ((i % 2) * 16);
> +		else
> +			vcdt2 |= tmp << ((i % 2) * 16);
> +	}
> +
> +	switch (priv->lanes) {
> +	case 1:
> +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_0;
> +		break;
> +	case 2:
> +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_1 | PHYCNT_ENABLE_0;
> +		break;
> +	case 4:
> +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_3 | PHYCNT_ENABLE_2 |
> +			PHYCNT_ENABLE_1 | PHYCNT_ENABLE_0;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	ret = rcar_csi2_calc_phypll(priv, source, mf, &phypll);
> +	if (ret)
> +		return ret;
> +
> +	/* Init */
> +	rcar_csi2_write(priv, TREF_REG, TREF_TREF);
> +	rcar_csi2_reset(priv);
> +	rcar_csi2_write(priv, PHTC_REG, 0);
> +
> +	/* Configure */
> +	rcar_csi2_write(priv, FLD_REG, FLD_FLD_NUM(2) | FLD_FLD_EN4 |
> +			FLD_FLD_EN3 | FLD_FLD_EN2 | FLD_FLD_EN);
> +	rcar_csi2_write(priv, VCDT_REG, vcdt);
> +	rcar_csi2_write(priv, VCDT2_REG, vcdt2);
> +	/* Lanes are zero indexed */
> +	rcar_csi2_write(priv, LSWAP_REG,
> +			LSWAP_L0SEL(priv->lane_swap[0] - 1) |
> +			LSWAP_L1SEL(priv->lane_swap[1] - 1) |
> +			LSWAP_L2SEL(priv->lane_swap[2] - 1) |
> +			LSWAP_L3SEL(priv->lane_swap[3] - 1));

How are the lanes numbered?

Do you have a fixed number of lanes per receiver?

> +
> +	/* Start */
> +	rcar_csi2_write(priv, PHYPLL_REG, phypll);
> +	rcar_csi2_write(priv, PHYCNT_REG, phycnt);
> +	rcar_csi2_write(priv, LINKCNT_REG, LINKCNT_MONITOR_EN |
> +			LINKCNT_REG_MONI_PACT_EN | LINKCNT_ICLK_NONSTOP);
> +	rcar_csi2_write(priv, PHYCNT_REG, phycnt | PHYCNT_SHUTDOWNZ);
> +	rcar_csi2_write(priv, PHYCNT_REG, phycnt | PHYCNT_SHUTDOWNZ |
> +			PHYCNT_RSTZ);
> +
> +	return rcar_csi2_wait_phy_start(priv);
> +}
> +
> +static void rcar_csi2_stop(struct rcar_csi2 *priv)
> +{
> +	rcar_csi2_write(priv, PHYCNT_REG, 0);
> +
> +	rcar_csi2_reset(priv);
> +}
> +
> +static int rcar_csi2_sd_info(struct rcar_csi2 *priv, struct v4l2_subdev **sd)
> +{
> +	struct media_pad *pad;
> +
> +	pad = media_entity_remote_pad(&priv->pads[RCAR_CSI2_SINK]);
> +	if (!pad) {
> +		dev_err(priv->dev, "Could not find remote pad\n");
> +		return -ENODEV;
> +	}
> +
> +	*sd = media_entity_to_v4l2_subdev(pad->entity);
> +	if (!*sd) {
> +		dev_err(priv->dev, "Could not find remote subdevice\n");
> +		return -ENODEV;
> +	}
> +
> +	return 0;
> +}
> +
> +static int rcar_csi2_s_stream(struct v4l2_subdev *sd, int enable)
> +{
> +	struct rcar_csi2 *priv = sd_to_csi2(sd);
> +	struct v4l2_subdev *nextsd;
> +	int ret;
> +
> +	mutex_lock(&priv->lock);
> +
> +	ret = rcar_csi2_sd_info(priv, &nextsd);
> +	if (ret)
> +		goto out;
> +
> +	priv->stream_count += enable ? 1 : -1;
> +
> +	if (enable && priv->stream_count == 1) {
> +		ret =  rcar_csi2_start(priv);
> +		if (ret)
> +			goto out;
> +		ret = v4l2_subdev_call(nextsd, video, s_stream, 1);
> +
> +	} else if (!enable && !priv->stream_count) {
> +		rcar_csi2_stop(priv);
> +		ret = v4l2_subdev_call(nextsd, video, s_stream, 0);
> +	}
> +out:
> +	mutex_unlock(&priv->lock);
> +
> +	return ret;
> +}
> +
> +static int rcar_csi2_s_power(struct v4l2_subdev *sd, int on)
> +{
> +	struct rcar_csi2 *priv = sd_to_csi2(sd);
> +
> +	if (on)
> +		pm_runtime_get_sync(priv->dev);
> +	else
> +		pm_runtime_put(priv->dev);
> +
> +	return 0;
> +}
> +
> +static int rcar_csi2_set_pad_format(struct v4l2_subdev *sd,
> +				    struct v4l2_subdev_pad_config *cfg,
> +				    struct v4l2_subdev_format *format)
> +{
> +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> +
> +	if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE)
> +		priv->mf = format->format;

How about the try formats? E.g.

*v4l2_subdev_get_try_format() = format->fmt;

> +
> +	return 0;
> +}
> +
> +static int rcar_csi2_get_pad_format(struct v4l2_subdev *sd,
> +				    struct v4l2_subdev_pad_config *cfg,
> +				    struct v4l2_subdev_format *format)
> +{
> +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> +
> +	format->format = priv->mf;

Ditto.

> +
> +	return 0;
> +}
> +
> +static const struct v4l2_subdev_video_ops rcar_csi2_video_ops = {
> +	.s_stream = rcar_csi2_s_stream,
> +};
> +
> +static const struct v4l2_subdev_core_ops rcar_csi2_subdev_core_ops = {
> +	.s_power = rcar_csi2_s_power,
> +};
> +
> +static const struct v4l2_subdev_pad_ops rcar_csi2_pad_ops = {
> +	.set_fmt = rcar_csi2_set_pad_format,
> +	.get_fmt = rcar_csi2_get_pad_format,
> +};
> +
> +static const struct v4l2_subdev_ops rcar_csi2_subdev_ops = {
> +	.video	= &rcar_csi2_video_ops,
> +	.core	= &rcar_csi2_subdev_core_ops,
> +	.pad	= &rcar_csi2_pad_ops,
> +};
> +
> +/* -----------------------------------------------------------------------------
> + * Async and registered of subdevices and links
> + */
> +
> +#define notifier_to_priv(n) container_of(n, struct rcar_csi2, notifier)
> +
> +static int rcar_csi2_notify_complete(struct v4l2_async_notifier *notifier)
> +{
> +	struct rcar_csi2 *priv = notifier_to_priv(notifier);
> +	int ret;
> +
> +	ret = v4l2_device_register_subdev_nodes(priv->subdev.v4l2_dev);
> +	if (ret) {
> +		dev_err(priv->dev, "Failed to register subdev nodes\n");
> +		return ret;
> +	}
> +
> +	return media_create_pad_link(&priv->remote.subdev->entity,
> +				     priv->remote.source_pad,
> +				     &priv->subdev.entity, 0,
> +				     MEDIA_LNK_FL_ENABLED |
> +				     MEDIA_LNK_FL_IMMUTABLE);
> +}
> +
> +static int rcar_csi2_notify_bound(struct v4l2_async_notifier *notifier,
> +				   struct v4l2_subdev *subdev,
> +				   struct v4l2_async_subdev *asd)
> +{
> +	struct rcar_csi2 *priv = notifier_to_priv(notifier);
> +	int ret;
> +
> +	v4l2_set_subdev_hostdata(subdev, priv);
> +
> +	ret = media_entity_pad_from_fwnode(&subdev->entity,
> +					   priv->remote.fwnode,
> +					   MEDIA_PAD_FL_SOURCE,
> +					   &priv->remote.source_pad);
> +	if (ret) {
> +		dev_err(priv->dev, "Failed to find pad for %s\n",
> +			subdev->name);
> +		return ret;
> +	}
> +
> +	dev_dbg(priv->dev, "Bound %s pad: %d\n", subdev->name,
> +		priv->remote.source_pad);
> +	priv->remote.subdev = subdev;
> +
> +	return 0;
> +}

A newline would be nice here.

> +static void rcar_csi2_notify_unbind(struct v4l2_async_notifier *notifier,
> +				     struct v4l2_subdev *subdev,
> +				     struct v4l2_async_subdev *asd)
> +{
> +	struct rcar_csi2 *priv = notifier_to_priv(notifier);
> +
> +	dev_dbg(priv->dev, "Unbind %s\n", subdev->name);
> +	priv->remote.subdev = NULL;
> +}
> +
> +static int rcar_csi2_registered(struct v4l2_subdev *sd)
> +{
> +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> +	struct v4l2_async_subdev **subdevs = NULL;
> +	int ret;
> +
> +	subdevs = devm_kzalloc(priv->dev, sizeof(*subdevs), GFP_KERNEL);
> +	if (subdevs == NULL)
> +		return -ENOMEM;
> +
> +	subdevs[0] = &priv->remote.asd;
> +
> +	priv->notifier.num_subdevs = 1;
> +	priv->notifier.subdevs = subdevs;
> +	priv->notifier.bound = rcar_csi2_notify_bound;
> +	priv->notifier.unbind = rcar_csi2_notify_unbind;
> +	priv->notifier.complete = rcar_csi2_notify_complete;
> +
> +	ret = v4l2_async_subnotifier_register(&priv->subdev, &priv->notifier);
> +	if (ret < 0) {
> +		dev_err(priv->dev, "Notifier registration failed\n");
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static void rcar_csi2_unregistered(struct v4l2_subdev *sd)
> +{
> +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> +
> +	v4l2_async_subnotifier_unregister(&priv->notifier);
> +}
> +
> +static const struct v4l2_subdev_internal_ops rcar_csi2_internal_ops = {
> +	.registered = rcar_csi2_registered,
> +	.unregistered = rcar_csi2_unregistered,
> +};
> +
> +static int rcar_csi2_parse_dt_subdevice(struct rcar_csi2 *priv)
> +{
> +	struct device_node *remote, *ep;
> +	struct v4l2_fwnode_endpoint v4l2_ep;
> +	int ret;
> +
> +	ep = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0);
> +	if (!ep) {
> +		dev_err(priv->dev, "Not connected to subdevice\n");
> +		return -EINVAL;
> +	}
> +
> +	ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &v4l2_ep);
> +	if (ret) {
> +		dev_err(priv->dev, "Could not parse v4l2 endpoint\n");
> +		of_node_put(ep);
> +		return -EINVAL;
> +	}
> +
> +	if (v4l2_ep.bus_type != V4L2_MBUS_CSI2) {
> +		dev_err(priv->dev, "Unknown media bus type: 0x%x\n",
> +			v4l2_ep.bus_type);
> +		of_node_put(ep);
> +		return -EINVAL;
> +	}
> +
> +	priv->remote.fwnode =
> +		fwnode_graph_get_remote_endpoint(of_fwnode_handle(ep));
> +
> +	remote = of_graph_get_remote_port_parent(ep);
> +	of_node_put(ep);
> +	if (!remote) {
> +		dev_err(priv->dev, "No subdevice found for endpoint '%s'\n",
> +			of_node_full_name(ep));
> +		return -EINVAL;
> +	}
> +
> +	priv->remote.asd.match.fwnode.fwnode = of_fwnode_handle(remote);
> +	priv->remote.asd.match_type = V4L2_ASYNC_MATCH_FWNODE;
> +
> +	dev_dbg(priv->dev, "Found '%s'\n", of_node_full_name(remote));
> +
> +	return 0;
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Platform Device Driver
> + */
> +
> +static const struct of_device_id rcar_csi2_of_table[] = {
> +	{ .compatible = "renesas,rcar-gen3-csi2" },
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(of, rcar_csi2_of_table);
> +
> +static const struct media_entity_operations rcar_csi2_entity_ops = {
> +	.link_validate = v4l2_subdev_link_validate,
> +};
> +
> +static int rcar_csi2_parse_dt_settings(struct rcar_csi2 *priv)
> +{
> +	struct v4l2_fwnode_endpoint v4l2_ep;
> +	struct device_node *ep;
> +	unsigned int i;
> +	int ret;
> +
> +	ep = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0);
> +	if (!ep)
> +		return -EINVAL;
> +
> +	ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &v4l2_ep);
> +	of_node_put(ep);
> +	if (ret) {
> +		dev_err(priv->dev, "Could not parse v4l2 endpoint\n");
> +		return -EINVAL;
> +	}
> +
> +	if (v4l2_ep.bus_type != V4L2_MBUS_CSI2) {
> +		dev_err(priv->dev, "Unsupported media bus type for %s\n",
> +			of_node_full_name(ep));
> +		return -EINVAL;
> +	}
> +
> +	priv->lanes = v4l2_ep.bus.mipi_csi2.num_data_lanes;
> +	if (priv->lanes != 1 && priv->lanes != 2 && priv->lanes != 4) {
> +		dev_err(priv->dev, "Unsupported number of data-lanes: %d\n",
> +			priv->lanes);
> +		return -EINVAL;
> +	}
> +
> +	for (i = 0; i < ARRAY_SIZE(priv->lane_swap); i++) {
> +		priv->lane_swap[i] = i < priv->lanes ?
> +			v4l2_ep.bus.mipi_csi2.data_lanes[i] : i;
> +
> +		/* Check for valid lane number */
> +		if (priv->lane_swap[i] < 1 || priv->lane_swap[i] > 4) {

Do you also support for three lanes? Based on the code elsewhere, it doesn't
seem like that.

> +			dev_err(priv->dev, "data-lanes must be in 1-4 range\n");
> +			return -EINVAL;
> +		}
> +	}
> +
> +	return 0;
> +}
> +
> +static int rcar_csi2_probe_resources(struct rcar_csi2 *priv,
> +				     struct platform_device *pdev)
> +{
> +	struct resource *mem;
> +	int irq;
> +
> +	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!mem)
> +		return -ENODEV;
> +
> +	priv->base = devm_ioremap_resource(&pdev->dev, mem);
> +	if (IS_ERR(priv->base))
> +		return PTR_ERR(priv->base);
> +
> +	irq = platform_get_irq(pdev, 0);
> +	if (irq < 0)
> +		return irq;
> +
> +	return 0;
> +}
> +
> +static int rcar_csi2_probe(struct platform_device *pdev)
> +{
> +	struct rcar_csi2 *priv;
> +	unsigned int i;
> +	int ret;
> +
> +	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
> +
> +	priv->dev = &pdev->dev;
> +
> +	mutex_init(&priv->lock);
> +	priv->stream_count = 0;
> +
> +	ret = rcar_csi2_parse_dt_settings(priv);
> +	if (ret)
> +		return ret;
> +
> +	ret = rcar_csi2_parse_dt_subdevice(priv);
> +	if (ret)
> +		return ret;
> +
> +	ret = rcar_csi2_probe_resources(priv, pdev);
> +	if (ret) {
> +		dev_err(priv->dev, "Failed to get resources\n");
> +		return ret;
> +	}
> +
> +	platform_set_drvdata(pdev, priv);
> +
> +	priv->subdev.owner = THIS_MODULE;
> +	priv->subdev.dev = &pdev->dev;
> +	v4l2_subdev_init(&priv->subdev, &rcar_csi2_subdev_ops);
> +	v4l2_set_subdevdata(&priv->subdev, &pdev->dev);
> +	snprintf(priv->subdev.name, V4L2_SUBDEV_NAME_SIZE, "%s %s",
> +		 KBUILD_MODNAME, dev_name(&pdev->dev));
> +	priv->subdev.flags = V4L2_SUBDEV_FL_HAS_DEVNODE;
> +	priv->subdev.internal_ops = &rcar_csi2_internal_ops;
> +
> +	priv->subdev.entity.function = MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER;
> +	priv->subdev.entity.ops = &rcar_csi2_entity_ops;
> +
> +	priv->pads[RCAR_CSI2_SINK].flags = MEDIA_PAD_FL_SINK;
> +	for (i = RCAR_CSI2_SOURCE_VC0; i < NR_OF_RCAR_CSI2_PAD; i++)
> +		priv->pads[i].flags = MEDIA_PAD_FL_SOURCE;
> +
> +	ret = media_entity_pads_init(&priv->subdev.entity, NR_OF_RCAR_CSI2_PAD,
> +				     priv->pads);
> +	if (ret)
> +		return ret;
> +
> +	ret = v4l2_async_register_subdev(&priv->subdev);
> +	if (ret < 0)
> +		return ret;
> +
> +	pm_runtime_enable(&pdev->dev);
> +
> +	dev_info(priv->dev, "%d lanes found\n", priv->lanes);
> +
> +	return 0;
> +}
> +
> +static int rcar_csi2_remove(struct platform_device *pdev)
> +{
> +	struct rcar_csi2 *priv = platform_get_drvdata(pdev);
> +
> +	v4l2_async_unregister_subdev(&priv->subdev);
> +
> +	pm_runtime_disable(&pdev->dev);
> +
> +	return 0;
> +}
> +
> +static struct platform_driver __refdata rcar_csi2_pdrv = {
> +	.remove	= rcar_csi2_remove,
> +	.probe	= rcar_csi2_probe,
> +	.driver	= {
> +		.name	= "rcar-csi2",
> +		.of_match_table	= of_match_ptr(rcar_csi2_of_table),
> +	},
> +};
> +
> +module_platform_driver(rcar_csi2_pdrv);
> +
> +MODULE_AUTHOR("Niklas Söderlund <niklas.soderlund@ragnatech.se>");
> +MODULE_DESCRIPTION("Renesas R-Car MIPI CSI-2 receiver");
> +MODULE_LICENSE("GPL v2");

-- 
Regards,

Sakari Ailus
e-mail: sakari.ailus@iki.fi	XMPP: sailus@retiisi.org.uk

Re: [PATCH v7 2/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver driver

[Sakari Ailus]

Hi Niklas,

A few comments below.

On Wed, May 24, 2017 at 02:13:53AM +0200, Niklas S�derlund wrote:
> From: Niklas S�derlund <niklas.soderlund+renesas@ragnatech.se>
> 
> A V4L2 driver for Renesas R-Car MIPI CSI-2 receiver. The driver
> supports the rcar-vin driver on R-Car Gen3 SoCs where separate CSI-2
> hardware blocks are connected between the video sources and the video
> grabbers (VIN).
> 
> Driver is based on a prototype by Koji Matsuoka in the Renesas BSP.
> 
> Signed-off-by: Niklas S�derlund <niklas.soderlund+renesas@ragnatech.se>
> ---
>  drivers/media/platform/rcar-vin/Kconfig     |  12 +
>  drivers/media/platform/rcar-vin/Makefile    |   1 +
>  drivers/media/platform/rcar-vin/rcar-csi2.c | 867 ++++++++++++++++++++++++++++
>  3 files changed, 880 insertions(+)
>  create mode 100644 drivers/media/platform/rcar-vin/rcar-csi2.c
> 
> diff --git a/drivers/media/platform/rcar-vin/Kconfig b/drivers/media/platform/rcar-vin/Kconfig
> index af4c98b44d2e22cb..6875f30c1ae42631 100644
> --- a/drivers/media/platform/rcar-vin/Kconfig
> +++ b/drivers/media/platform/rcar-vin/Kconfig
> @@ -1,3 +1,15 @@
> +config VIDEO_RCAR_CSI2
> +	tristate "R-Car MIPI CSI-2 Receiver"
> +	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && OF
> +	depends on ARCH_RENESAS || COMPILE_TEST
> +	select V4L2_FWNODE
> +	---help---
> +	  Support for Renesas R-Car MIPI CSI-2 receiver.
> +	  Supports R-Car Gen3 SoCs.
> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called rcar-csi2.
> +
>  config VIDEO_RCAR_VIN
>  	tristate "R-Car Video Input (VIN) Driver"
>  	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && OF && HAS_DMA && MEDIA_CONTROLLER
> diff --git a/drivers/media/platform/rcar-vin/Makefile b/drivers/media/platform/rcar-vin/Makefile
> index 48c5632c21dc060b..5ab803d3e7c1aa57 100644
> --- a/drivers/media/platform/rcar-vin/Makefile
> +++ b/drivers/media/platform/rcar-vin/Makefile
> @@ -1,3 +1,4 @@
>  rcar-vin-objs = rcar-core.o rcar-dma.o rcar-v4l2.o
>  
> +obj-$(CONFIG_VIDEO_RCAR_CSI2) += rcar-csi2.o
>  obj-$(CONFIG_VIDEO_RCAR_VIN) += rcar-vin.o
> diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
> new file mode 100644
> index 0000000000000000..1175f1fe4b139a13
> --- /dev/null
> +++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
> @@ -0,0 +1,867 @@
> +/*
> + * Driver for Renesas R-Car MIPI CSI-2 Receiver
> + *
> + * Copyright (C) 2017 Renesas Electronics Corp.
> + *
> + * This program is free software; you can redistribute  it and/or modify it
> + * under  the terms of  the GNU General  Public License as published by the
> + * Free Software Foundation;  either version 2 of the  License, or (at your
> + * option) any later version.
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/of_graph.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +
> +#include <media/v4l2-ctrls.h>
> +#include <media/v4l2-device.h>
> +#include <media/v4l2-fwnode.h>
> +#include <media/v4l2-mc.h>
> +#include <media/v4l2-subdev.h>
> +
> +/* Register offsets and bits */
> +
> +/* Control Timing Select */
> +#define TREF_REG			0x00
> +#define TREF_TREF			(1 << 0)
> +
> +/* Software Reset */
> +#define SRST_REG			0x04
> +#define SRST_SRST			(1 << 0)
> +
> +/* PHY Operation Control */
> +#define PHYCNT_REG			0x08
> +#define PHYCNT_SHUTDOWNZ		(1 << 17)
> +#define PHYCNT_RSTZ			(1 << 16)
> +#define PHYCNT_ENABLECLK		(1 << 4)
> +#define PHYCNT_ENABLE_3			(1 << 3)
> +#define PHYCNT_ENABLE_2			(1 << 2)
> +#define PHYCNT_ENABLE_1			(1 << 1)
> +#define PHYCNT_ENABLE_0			(1 << 0)
> +
> +/* Checksum Control */
> +#define CHKSUM_REG			0x0c
> +#define CHKSUM_ECC_EN			(1 << 1)
> +#define CHKSUM_CRC_EN			(1 << 0)
> +
> +/*
> + * Channel Data Type Select
> + * VCDT[0-15]:  Channel 1 VCDT[16-31]:  Channel 2
> + * VCDT2[0-15]: Channel 3 VCDT2[16-31]: Channel 4
> + */
> +#define VCDT_REG			0x10
> +#define VCDT2_REG			0x14
> +#define VCDT_VCDTN_EN			(1 << 15)
> +#define VCDT_SEL_VC(n)			(((n) & 0x3) << 8)
> +#define VCDT_SEL_DTN_ON			(1 << 6)
> +#define VCDT_SEL_DT(n)			(((n) & 0x3f) << 0)
> +
> +/* Frame Data Type Select */
> +#define FRDT_REG			0x18
> +
> +/* Field Detection Control */
> +#define FLD_REG				0x1c
> +#define FLD_FLD_NUM(n)			(((n) & 0xff) << 16)
> +#define FLD_FLD_EN4			(1 << 3)
> +#define FLD_FLD_EN3			(1 << 2)
> +#define FLD_FLD_EN2			(1 << 1)
> +#define FLD_FLD_EN			(1 << 0)
> +
> +/* Automatic Standby Control */
> +#define ASTBY_REG			0x20
> +
> +/* Long Data Type Setting 0 */
> +#define LNGDT0_REG			0x28
> +
> +/* Long Data Type Setting 1 */
> +#define LNGDT1_REG			0x2c
> +
> +/* Interrupt Enable */
> +#define INTEN_REG			0x30
> +
> +/* Interrupt Source Mask */
> +#define INTCLOSE_REG			0x34
> +
> +/* Interrupt Status Monitor */
> +#define INTSTATE_REG			0x38
> +
> +/* Interrupt Error Status Monitor */
> +#define INTERRSTATE_REG			0x3c
> +
> +/* Short Packet Data */
> +#define SHPDAT_REG			0x40
> +
> +/* Short Packet Count */
> +#define SHPCNT_REG			0x44
> +
> +/* LINK Operation Control */
> +#define LINKCNT_REG			0x48
> +#define LINKCNT_MONITOR_EN		(1 << 31)
> +#define LINKCNT_REG_MONI_PACT_EN	(1 << 25)
> +#define LINKCNT_ICLK_NONSTOP		(1 << 24)
> +
> +/* Lane Swap */
> +#define LSWAP_REG			0x4c
> +#define LSWAP_L3SEL(n)			(((n) & 0x3) << 6)
> +#define LSWAP_L2SEL(n)			(((n) & 0x3) << 4)
> +#define LSWAP_L1SEL(n)			(((n) & 0x3) << 2)
> +#define LSWAP_L0SEL(n)			(((n) & 0x3) << 0)
> +
> +/* PHY Test Interface Clear */
> +#define PHTC_REG			0x58
> +#define PHTC_TESTCLR			(1 << 0)
> +
> +/* PHY Frequency Control */
> +#define PHYPLL_REG			0x68
> +#define PHYPLL_HSFREQRANGE(n)		((n) << 16)
> +
> +struct phypll_hsfreqrange {
> +	unsigned int	mbps;
> +	unsigned char	reg;
> +};
> +
> +static const struct phypll_hsfreqrange phypll_hsfreqrange_map[] = {
> +	{ .mbps =   80,	.reg = 0x00 },
> +	{ .mbps =   90,	.reg = 0x10 },
> +	{ .mbps =  100,	.reg = 0x20 },
> +	{ .mbps =  110,	.reg = 0x30 },
> +	{ .mbps =  120,	.reg = 0x01 },
> +	{ .mbps =  130,	.reg = 0x11 },
> +	{ .mbps =  140,	.reg = 0x21 },
> +	{ .mbps =  150,	.reg = 0x31 },
> +	{ .mbps =  160,	.reg = 0x02 },
> +	{ .mbps =  170,	.reg = 0x12 },
> +	{ .mbps =  180,	.reg = 0x22 },
> +	{ .mbps =  190,	.reg = 0x32 },
> +	{ .mbps =  205,	.reg = 0x03 },
> +	{ .mbps =  220,	.reg = 0x13 },
> +	{ .mbps =  235,	.reg = 0x23 },
> +	{ .mbps =  250,	.reg = 0x33 },
> +	{ .mbps =  275,	.reg = 0x04 },
> +	{ .mbps =  300,	.reg = 0x14 },
> +	{ .mbps =  325,	.reg = 0x05 },
> +	{ .mbps =  350,	.reg = 0x15 },
> +	{ .mbps =  400,	.reg = 0x25 },
> +	{ .mbps =  450,	.reg = 0x06 },
> +	{ .mbps =  500,	.reg = 0x16 },
> +	{ .mbps =  550,	.reg = 0x07 },
> +	{ .mbps =  600,	.reg = 0x17 },
> +	{ .mbps =  650,	.reg = 0x08 },
> +	{ .mbps =  700,	.reg = 0x18 },
> +	{ .mbps =  750,	.reg = 0x09 },
> +	{ .mbps =  800,	.reg = 0x19 },
> +	{ .mbps =  850,	.reg = 0x29 },
> +	{ .mbps =  900,	.reg = 0x39 },
> +	{ .mbps =  950,	.reg = 0x0A },
> +	{ .mbps = 1000,	.reg = 0x1A },
> +	{ .mbps = 1050,	.reg = 0x2A },
> +	{ .mbps = 1100,	.reg = 0x3A },
> +	{ .mbps = 1150,	.reg = 0x0B },
> +	{ .mbps = 1200,	.reg = 0x1B },
> +	{ .mbps = 1250,	.reg = 0x2B },
> +	{ .mbps = 1300,	.reg = 0x3B },
> +	{ .mbps = 1350,	.reg = 0x0C },
> +	{ .mbps = 1400,	.reg = 0x1C },
> +	{ .mbps = 1450,	.reg = 0x2C },
> +	{ .mbps = 1500,	.reg = 0x3C },
> +	/* guard */
> +	{ .mbps =   0,	.reg = 0x00 },
> +};
> +
> +/* PHY ESC Error Monitor */
> +#define PHEERM_REG			0x74
> +
> +/* PHY Clock Lane Monitor */
> +#define PHCLM_REG			0x78
> +
> +/* PHY Data Lane Monitor */
> +#define PHDLM_REG			0x7c
> +
> +struct rcar_csi2_format {
> +	unsigned int code;
> +	unsigned int datatype;
> +	unsigned int bpp;
> +};
> +
> +static const struct rcar_csi2_format rcar_csi2_formats[] = {
> +	{ .code = MEDIA_BUS_FMT_RGB888_1X24,	.datatype = 0x24, .bpp = 24},
> +	{ .code = MEDIA_BUS_FMT_UYVY8_1X16,	.datatype = 0x1e, .bpp = 8 },
> +	{ .code = MEDIA_BUS_FMT_UYVY8_2X8,	.datatype = 0x1e, .bpp = 8 },
> +	{ .code = MEDIA_BUS_FMT_YUYV10_2X10,	.datatype = 0x1e, .bpp = 8 },
> +};
> +
> +static const struct rcar_csi2_format *rcar_csi2_code_to_fmt(unsigned int code)
> +{
> +	int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(rcar_csi2_formats); i++)
> +		if (rcar_csi2_formats[i].code == code)
> +			return rcar_csi2_formats + i;
> +	return NULL;
> +}
> +
> +enum rcar_csi2_pads {
> +	RCAR_CSI2_SINK,
> +	RCAR_CSI2_SOURCE_VC0,
> +	RCAR_CSI2_SOURCE_VC1,
> +	RCAR_CSI2_SOURCE_VC2,
> +	RCAR_CSI2_SOURCE_VC3,
> +	NR_OF_RCAR_CSI2_PAD,
> +};
> +
> +struct rcar_csi2 {
> +	struct device *dev;
> +	void __iomem *base;
> +
> +	unsigned short lanes;
> +	unsigned char lane_swap[4];
> +
> +	struct v4l2_subdev subdev;
> +	struct media_pad pads[NR_OF_RCAR_CSI2_PAD];
> +
> +	struct v4l2_mbus_framefmt mf;
> +
> +	struct mutex lock;
> +	int stream_count;
> +
> +	struct v4l2_async_notifier notifier;
> +	struct {
> +		struct v4l2_async_subdev asd;
> +		struct v4l2_subdev *subdev;
> +		struct fwnode_handle *fwnode;
> +		unsigned int source_pad;
> +	} remote;
> +};
> +
> +static inline struct rcar_csi2 *sd_to_csi2(struct v4l2_subdev *sd)
> +{
> +	return container_of(sd, struct rcar_csi2, subdev);
> +}
> +
> +static u32 rcar_csi2_read(struct rcar_csi2 *priv, unsigned int reg)
> +{
> +	return ioread32(priv->base + reg);
> +}
> +
> +static void rcar_csi2_write(struct rcar_csi2 *priv, unsigned int reg, u32 data)
> +{
> +	iowrite32(data, priv->base + reg);
> +}
> +
> +static void rcar_csi2_reset(struct rcar_csi2 *priv)
> +{
> +	rcar_csi2_write(priv, SRST_REG, SRST_SRST);
> +	rcar_csi2_write(priv, SRST_REG, 0);
> +}
> +
> +static int rcar_csi2_wait_phy_start(struct rcar_csi2 *priv)
> +{
> +	int timeout;
> +
> +	/* Wait for the clock and data lanes to enter LP-11 state. */
> +	for (timeout = 100; timeout >= 0; timeout--) {
> +		const u32 lane_mask = (1 << priv->lanes) - 1;
> +
> +		if ((rcar_csi2_read(priv, PHCLM_REG) & 1) == 1 &&
> +		    (rcar_csi2_read(priv, PHDLM_REG) & lane_mask) == lane_mask)
> +			return 0;
> +
> +		msleep(20);
> +	}
> +
> +	dev_err(priv->dev, "Timeout waiting for LP-11 state\n");
> +
> +	return -ETIMEDOUT;
> +}
> +
> +static int rcar_csi2_calc_phypll(struct rcar_csi2 *priv,
> +				 struct v4l2_subdev *source,
> +				 struct v4l2_mbus_framefmt *mf,
> +				 u32 *phypll)
> +{
> +	const struct phypll_hsfreqrange *hsfreq;
> +	const struct rcar_csi2_format *format;
> +	struct v4l2_ext_controls ctrls;
> +	struct v4l2_ext_control ctrl;
> +	u64 mbps;
> +	int ret;
> +
> +	memset(&ctrls, 0, sizeof(ctrls));
> +	memset(&ctrl, 0, sizeof(ctrl));
> +
> +	ctrl.id = V4L2_CID_PIXEL_RATE;
> +
> +	ctrls.count = 1;
> +	ctrls.controls = &ctrl;
> +
> +	ret = v4l2_g_ext_ctrls(source->ctrl_handler, &ctrls);

v4l2_ctrl_g_ctrl_int64(), please. Or do I miss something?

> +	if (ret < 0) {
> +		dev_err(priv->dev, "no link freq control in subdev %s\n",
> +			source->name);
> +		return ret;
> +	}
> +
> +	format = rcar_csi2_code_to_fmt(mf->code);
> +	if (!format) {
> +		dev_err(priv->dev, "Unknown format: %d\n", mf->code);
> +		return -EINVAL;
> +	}
> +
> +	mbps = ctrl.value64 * format->bpp;
> +	do_div(mbps, priv->lanes * 1000000);
> +
> +	for (hsfreq = phypll_hsfreqrange_map; hsfreq->mbps != 0; hsfreq++)
> +		if (hsfreq->mbps >= mbps)
> +			break;
> +
> +	if (!hsfreq->mbps) {
> +		dev_err(priv->dev, "Unsupported PHY speed (%llu Mbps)", mbps);
> +		return -ERANGE;
> +	}
> +
> +	dev_dbg(priv->dev, "PHY HSFREQRANGE requested %llu got %u Mbps\n", mbps,
> +		hsfreq->mbps);
> +
> +	*phypll = PHYPLL_HSFREQRANGE(hsfreq->reg);
> +
> +	return 0;
> +}
> +
> +static int rcar_csi2_start(struct rcar_csi2 *priv)
> +{
> +	const struct rcar_csi2_format *format;
> +	struct v4l2_subdev_format fmt;
> +	struct media_pad *source_pad;
> +	struct v4l2_subdev *source = NULL;
> +	struct v4l2_mbus_framefmt *mf = &fmt.format;
> +	u32 phycnt, phypll, tmp;
> +	u32 vcdt = 0, vcdt2 = 0;
> +	unsigned int i;
> +	int ret;
> +
> +	source_pad =
> +		media_entity_remote_pad(&priv->subdev.entity.pads[RCAR_CSI2_SINK]);

Over 80 characters per line. I think you could split this up differently.

> +	if (!source_pad) {
> +		dev_err(priv->dev, "Could not find remote source pad\n");
> +		return -ENODEV;
> +	}
> +
> +	source = media_entity_to_v4l2_subdev(source_pad->entity);
> +	if (!source) {
> +		dev_err(priv->dev, "Could not find remote subdevice\n");
> +		return -ENODEV;
> +	}
> +
> +	dev_dbg(priv->dev, "Using source %s pad: %u\n", source->name,
> +		source_pad->index);
> +
> +	fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
> +	fmt.pad = source_pad->index;
> +	ret = v4l2_subdev_call(source, pad, get_fmt, NULL, &fmt);
> +	if (ret)
> +		return ret;
> +
> +	dev_dbg(priv->dev, "Input size (%dx%d%c)\n", mf->width,
> +		mf->height, mf->field == V4L2_FIELD_NONE ? 'p' : 'i');
> +
> +	/*
> +	 * Enable all Virtual Channels
> +	 *
> +	 * NOTE: I'ts not possible to get individual format for each

"It's"

> +	 *       source virtual channel. Once this is possible in V4L2
> +	 *       it should be used here.
> +	 */
> +	for (i = 0; i < 4; i++) {
> +
> +		format = rcar_csi2_code_to_fmt(mf->code);
> +		if (!format) {
> +			dev_err(priv->dev, "Unsupported media bus format: %d\n",
> +				mf->code);
> +			return -EINVAL;
> +		}
> +
> +		tmp = VCDT_SEL_VC(i) | VCDT_VCDTN_EN | VCDT_SEL_DTN_ON |
> +			VCDT_SEL_DT(format->datatype);
> +
> +		/* Store in correct reg and offset */
> +		if (i < 2)
> +			vcdt |= tmp << ((i % 2) * 16);
> +		else
> +			vcdt2 |= tmp << ((i % 2) * 16);
> +	}
> +
> +	switch (priv->lanes) {
> +	case 1:
> +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_0;
> +		break;
> +	case 2:
> +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_1 | PHYCNT_ENABLE_0;
> +		break;
> +	case 4:
> +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_3 | PHYCNT_ENABLE_2 |
> +			PHYCNT_ENABLE_1 | PHYCNT_ENABLE_0;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	ret = rcar_csi2_calc_phypll(priv, source, mf, &phypll);
> +	if (ret)
> +		return ret;
> +
> +	/* Init */
> +	rcar_csi2_write(priv, TREF_REG, TREF_TREF);
> +	rcar_csi2_reset(priv);
> +	rcar_csi2_write(priv, PHTC_REG, 0);
> +
> +	/* Configure */
> +	rcar_csi2_write(priv, FLD_REG, FLD_FLD_NUM(2) | FLD_FLD_EN4 |
> +			FLD_FLD_EN3 | FLD_FLD_EN2 | FLD_FLD_EN);
> +	rcar_csi2_write(priv, VCDT_REG, vcdt);
> +	rcar_csi2_write(priv, VCDT2_REG, vcdt2);
> +	/* Lanes are zero indexed */
> +	rcar_csi2_write(priv, LSWAP_REG,
> +			LSWAP_L0SEL(priv->lane_swap[0] - 1) |
> +			LSWAP_L1SEL(priv->lane_swap[1] - 1) |
> +			LSWAP_L2SEL(priv->lane_swap[2] - 1) |
> +			LSWAP_L3SEL(priv->lane_swap[3] - 1));

How are the lanes numbered?

Do you have a fixed number of lanes per receiver?

> +
> +	/* Start */
> +	rcar_csi2_write(priv, PHYPLL_REG, phypll);
> +	rcar_csi2_write(priv, PHYCNT_REG, phycnt);
> +	rcar_csi2_write(priv, LINKCNT_REG, LINKCNT_MONITOR_EN |
> +			LINKCNT_REG_MONI_PACT_EN | LINKCNT_ICLK_NONSTOP);
> +	rcar_csi2_write(priv, PHYCNT_REG, phycnt | PHYCNT_SHUTDOWNZ);
> +	rcar_csi2_write(priv, PHYCNT_REG, phycnt | PHYCNT_SHUTDOWNZ |
> +			PHYCNT_RSTZ);
> +
> +	return rcar_csi2_wait_phy_start(priv);
> +}
> +
> +static void rcar_csi2_stop(struct rcar_csi2 *priv)
> +{
> +	rcar_csi2_write(priv, PHYCNT_REG, 0);
> +
> +	rcar_csi2_reset(priv);
> +}
> +
> +static int rcar_csi2_sd_info(struct rcar_csi2 *priv, struct v4l2_subdev **sd)
> +{
> +	struct media_pad *pad;
> +
> +	pad = media_entity_remote_pad(&priv->pads[RCAR_CSI2_SINK]);
> +	if (!pad) {
> +		dev_err(priv->dev, "Could not find remote pad\n");
> +		return -ENODEV;
> +	}
> +
> +	*sd = media_entity_to_v4l2_subdev(pad->entity);
> +	if (!*sd) {
> +		dev_err(priv->dev, "Could not find remote subdevice\n");
> +		return -ENODEV;
> +	}
> +
> +	return 0;
> +}
> +
> +static int rcar_csi2_s_stream(struct v4l2_subdev *sd, int enable)
> +{
> +	struct rcar_csi2 *priv = sd_to_csi2(sd);
> +	struct v4l2_subdev *nextsd;
> +	int ret;
> +
> +	mutex_lock(&priv->lock);
> +
> +	ret = rcar_csi2_sd_info(priv, &nextsd);
> +	if (ret)
> +		goto out;
> +
> +	priv->stream_count += enable ? 1 : -1;
> +
> +	if (enable && priv->stream_count == 1) {
> +		ret =  rcar_csi2_start(priv);
> +		if (ret)
> +			goto out;
> +		ret = v4l2_subdev_call(nextsd, video, s_stream, 1);
> +
> +	} else if (!enable && !priv->stream_count) {
> +		rcar_csi2_stop(priv);
> +		ret = v4l2_subdev_call(nextsd, video, s_stream, 0);
> +	}
> +out:
> +	mutex_unlock(&priv->lock);
> +
> +	return ret;
> +}
> +
> +static int rcar_csi2_s_power(struct v4l2_subdev *sd, int on)
> +{
> +	struct rcar_csi2 *priv = sd_to_csi2(sd);
> +
> +	if (on)
> +		pm_runtime_get_sync(priv->dev);
> +	else
> +		pm_runtime_put(priv->dev);
> +
> +	return 0;
> +}
> +
> +static int rcar_csi2_set_pad_format(struct v4l2_subdev *sd,
> +				    struct v4l2_subdev_pad_config *cfg,
> +				    struct v4l2_subdev_format *format)
> +{
> +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> +
> +	if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE)
> +		priv->mf = format->format;

How about the try formats? E.g.

*v4l2_subdev_get_try_format() = format->fmt;

> +
> +	return 0;
> +}
> +
> +static int rcar_csi2_get_pad_format(struct v4l2_subdev *sd,
> +				    struct v4l2_subdev_pad_config *cfg,
> +				    struct v4l2_subdev_format *format)
> +{
> +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> +
> +	format->format = priv->mf;

Ditto.

> +
> +	return 0;
> +}
> +
> +static const struct v4l2_subdev_video_ops rcar_csi2_video_ops = {
> +	.s_stream = rcar_csi2_s_stream,
> +};
> +
> +static const struct v4l2_subdev_core_ops rcar_csi2_subdev_core_ops = {
> +	.s_power = rcar_csi2_s_power,
> +};
> +
> +static const struct v4l2_subdev_pad_ops rcar_csi2_pad_ops = {
> +	.set_fmt = rcar_csi2_set_pad_format,
> +	.get_fmt = rcar_csi2_get_pad_format,
> +};
> +
> +static const struct v4l2_subdev_ops rcar_csi2_subdev_ops = {
> +	.video	= &rcar_csi2_video_ops,
> +	.core	= &rcar_csi2_subdev_core_ops,
> +	.pad	= &rcar_csi2_pad_ops,
> +};
> +
> +/* -----------------------------------------------------------------------------
> + * Async and registered of subdevices and links
> + */
> +
> +#define notifier_to_priv(n) container_of(n, struct rcar_csi2, notifier)
> +
> +static int rcar_csi2_notify_complete(struct v4l2_async_notifier *notifier)
> +{
> +	struct rcar_csi2 *priv = notifier_to_priv(notifier);
> +	int ret;
> +
> +	ret = v4l2_device_register_subdev_nodes(priv->subdev.v4l2_dev);
> +	if (ret) {
> +		dev_err(priv->dev, "Failed to register subdev nodes\n");
> +		return ret;
> +	}
> +
> +	return media_create_pad_link(&priv->remote.subdev->entity,
> +				     priv->remote.source_pad,
> +				     &priv->subdev.entity, 0,
> +				     MEDIA_LNK_FL_ENABLED |
> +				     MEDIA_LNK_FL_IMMUTABLE);
> +}
> +
> +static int rcar_csi2_notify_bound(struct v4l2_async_notifier *notifier,
> +				   struct v4l2_subdev *subdev,
> +				   struct v4l2_async_subdev *asd)
> +{
> +	struct rcar_csi2 *priv = notifier_to_priv(notifier);
> +	int ret;
> +
> +	v4l2_set_subdev_hostdata(subdev, priv);
> +
> +	ret = media_entity_pad_from_fwnode(&subdev->entity,
> +					   priv->remote.fwnode,
> +					   MEDIA_PAD_FL_SOURCE,
> +					   &priv->remote.source_pad);
> +	if (ret) {
> +		dev_err(priv->dev, "Failed to find pad for %s\n",
> +			subdev->name);
> +		return ret;
> +	}
> +
> +	dev_dbg(priv->dev, "Bound %s pad: %d\n", subdev->name,
> +		priv->remote.source_pad);
> +	priv->remote.subdev = subdev;
> +
> +	return 0;
> +}

A newline would be nice here.

> +static void rcar_csi2_notify_unbind(struct v4l2_async_notifier *notifier,
> +				     struct v4l2_subdev *subdev,
> +				     struct v4l2_async_subdev *asd)
> +{
> +	struct rcar_csi2 *priv = notifier_to_priv(notifier);
> +
> +	dev_dbg(priv->dev, "Unbind %s\n", subdev->name);
> +	priv->remote.subdev = NULL;
> +}
> +
> +static int rcar_csi2_registered(struct v4l2_subdev *sd)
> +{
> +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> +	struct v4l2_async_subdev **subdevs = NULL;
> +	int ret;
> +
> +	subdevs = devm_kzalloc(priv->dev, sizeof(*subdevs), GFP_KERNEL);
> +	if (subdevs == NULL)
> +		return -ENOMEM;
> +
> +	subdevs[0] = &priv->remote.asd;
> +
> +	priv->notifier.num_subdevs = 1;
> +	priv->notifier.subdevs = subdevs;
> +	priv->notifier.bound = rcar_csi2_notify_bound;
> +	priv->notifier.unbind = rcar_csi2_notify_unbind;
> +	priv->notifier.complete = rcar_csi2_notify_complete;
> +
> +	ret = v4l2_async_subnotifier_register(&priv->subdev, &priv->notifier);
> +	if (ret < 0) {
> +		dev_err(priv->dev, "Notifier registration failed\n");
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static void rcar_csi2_unregistered(struct v4l2_subdev *sd)
> +{
> +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> +
> +	v4l2_async_subnotifier_unregister(&priv->notifier);
> +}
> +
> +static const struct v4l2_subdev_internal_ops rcar_csi2_internal_ops = {
> +	.registered = rcar_csi2_registered,
> +	.unregistered = rcar_csi2_unregistered,
> +};
> +
> +static int rcar_csi2_parse_dt_subdevice(struct rcar_csi2 *priv)
> +{
> +	struct device_node *remote, *ep;
> +	struct v4l2_fwnode_endpoint v4l2_ep;
> +	int ret;
> +
> +	ep = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0);
> +	if (!ep) {
> +		dev_err(priv->dev, "Not connected to subdevice\n");
> +		return -EINVAL;
> +	}
> +
> +	ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &v4l2_ep);
> +	if (ret) {
> +		dev_err(priv->dev, "Could not parse v4l2 endpoint\n");
> +		of_node_put(ep);
> +		return -EINVAL;
> +	}
> +
> +	if (v4l2_ep.bus_type != V4L2_MBUS_CSI2) {
> +		dev_err(priv->dev, "Unknown media bus type: 0x%x\n",
> +			v4l2_ep.bus_type);
> +		of_node_put(ep);
> +		return -EINVAL;
> +	}
> +
> +	priv->remote.fwnode =
> +		fwnode_graph_get_remote_endpoint(of_fwnode_handle(ep));
> +
> +	remote = of_graph_get_remote_port_parent(ep);
> +	of_node_put(ep);
> +	if (!remote) {
> +		dev_err(priv->dev, "No subdevice found for endpoint '%s'\n",
> +			of_node_full_name(ep));
> +		return -EINVAL;
> +	}
> +
> +	priv->remote.asd.match.fwnode.fwnode = of_fwnode_handle(remote);
> +	priv->remote.asd.match_type = V4L2_ASYNC_MATCH_FWNODE;
> +
> +	dev_dbg(priv->dev, "Found '%s'\n", of_node_full_name(remote));
> +
> +	return 0;
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Platform Device Driver
> + */
> +
> +static const struct of_device_id rcar_csi2_of_table[] = {
> +	{ .compatible = "renesas,rcar-gen3-csi2" },
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(of, rcar_csi2_of_table);
> +
> +static const struct media_entity_operations rcar_csi2_entity_ops = {
> +	.link_validate = v4l2_subdev_link_validate,
> +};
> +
> +static int rcar_csi2_parse_dt_settings(struct rcar_csi2 *priv)
> +{
> +	struct v4l2_fwnode_endpoint v4l2_ep;
> +	struct device_node *ep;
> +	unsigned int i;
> +	int ret;
> +
> +	ep = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0);
> +	if (!ep)
> +		return -EINVAL;
> +
> +	ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &v4l2_ep);
> +	of_node_put(ep);
> +	if (ret) {
> +		dev_err(priv->dev, "Could not parse v4l2 endpoint\n");
> +		return -EINVAL;
> +	}
> +
> +	if (v4l2_ep.bus_type != V4L2_MBUS_CSI2) {
> +		dev_err(priv->dev, "Unsupported media bus type for %s\n",
> +			of_node_full_name(ep));
> +		return -EINVAL;
> +	}
> +
> +	priv->lanes = v4l2_ep.bus.mipi_csi2.num_data_lanes;
> +	if (priv->lanes != 1 && priv->lanes != 2 && priv->lanes != 4) {
> +		dev_err(priv->dev, "Unsupported number of data-lanes: %d\n",
> +			priv->lanes);
> +		return -EINVAL;
> +	}
> +
> +	for (i = 0; i < ARRAY_SIZE(priv->lane_swap); i++) {
> +		priv->lane_swap[i] = i < priv->lanes ?
> +			v4l2_ep.bus.mipi_csi2.data_lanes[i] : i;
> +
> +		/* Check for valid lane number */
> +		if (priv->lane_swap[i] < 1 || priv->lane_swap[i] > 4) {

Do you also support for three lanes? Based on the code elsewhere, it doesn't
seem like that.

> +			dev_err(priv->dev, "data-lanes must be in 1-4 range\n");
> +			return -EINVAL;
> +		}
> +	}
> +
> +	return 0;
> +}
> +
> +static int rcar_csi2_probe_resources(struct rcar_csi2 *priv,
> +				     struct platform_device *pdev)
> +{
> +	struct resource *mem;
> +	int irq;
> +
> +	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!mem)
> +		return -ENODEV;
> +
> +	priv->base = devm_ioremap_resource(&pdev->dev, mem);
> +	if (IS_ERR(priv->base))
> +		return PTR_ERR(priv->base);
> +
> +	irq = platform_get_irq(pdev, 0);
> +	if (irq < 0)
> +		return irq;
> +
> +	return 0;
> +}
> +
> +static int rcar_csi2_probe(struct platform_device *pdev)
> +{
> +	struct rcar_csi2 *priv;
> +	unsigned int i;
> +	int ret;
> +
> +	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
> +
> +	priv->dev = &pdev->dev;
> +
> +	mutex_init(&priv->lock);
> +	priv->stream_count = 0;
> +
> +	ret = rcar_csi2_parse_dt_settings(priv);
> +	if (ret)
> +		return ret;
> +
> +	ret = rcar_csi2_parse_dt_subdevice(priv);
> +	if (ret)
> +		return ret;
> +
> +	ret = rcar_csi2_probe_resources(priv, pdev);
> +	if (ret) {
> +		dev_err(priv->dev, "Failed to get resources\n");
> +		return ret;
> +	}
> +
> +	platform_set_drvdata(pdev, priv);
> +
> +	priv->subdev.owner = THIS_MODULE;
> +	priv->subdev.dev = &pdev->dev;
> +	v4l2_subdev_init(&priv->subdev, &rcar_csi2_subdev_ops);
> +	v4l2_set_subdevdata(&priv->subdev, &pdev->dev);
> +	snprintf(priv->subdev.name, V4L2_SUBDEV_NAME_SIZE, "%s %s",
> +		 KBUILD_MODNAME, dev_name(&pdev->dev));
> +	priv->subdev.flags = V4L2_SUBDEV_FL_HAS_DEVNODE;
> +	priv->subdev.internal_ops = &rcar_csi2_internal_ops;
> +
> +	priv->subdev.entity.function = MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER;
> +	priv->subdev.entity.ops = &rcar_csi2_entity_ops;
> +
> +	priv->pads[RCAR_CSI2_SINK].flags = MEDIA_PAD_FL_SINK;
> +	for (i = RCAR_CSI2_SOURCE_VC0; i < NR_OF_RCAR_CSI2_PAD; i++)
> +		priv->pads[i].flags = MEDIA_PAD_FL_SOURCE;
> +
> +	ret = media_entity_pads_init(&priv->subdev.entity, NR_OF_RCAR_CSI2_PAD,
> +				     priv->pads);
> +	if (ret)
> +		return ret;
> +
> +	ret = v4l2_async_register_subdev(&priv->subdev);
> +	if (ret < 0)
> +		return ret;
> +
> +	pm_runtime_enable(&pdev->dev);
> +
> +	dev_info(priv->dev, "%d lanes found\n", priv->lanes);
> +
> +	return 0;
> +}
> +
> +static int rcar_csi2_remove(struct platform_device *pdev)
> +{
> +	struct rcar_csi2 *priv = platform_get_drvdata(pdev);
> +
> +	v4l2_async_unregister_subdev(&priv->subdev);
> +
> +	pm_runtime_disable(&pdev->dev);
> +
> +	return 0;
> +}
> +
> +static struct platform_driver __refdata rcar_csi2_pdrv = {
> +	.remove	= rcar_csi2_remove,
> +	.probe	= rcar_csi2_probe,
> +	.driver	= {
> +		.name	= "rcar-csi2",
> +		.of_match_table	= of_match_ptr(rcar_csi2_of_table),
> +	},
> +};
> +
> +module_platform_driver(rcar_csi2_pdrv);
> +
> +MODULE_AUTHOR("Niklas S�derlund <niklas.soderlund@ragnatech.se>");
> +MODULE_DESCRIPTION("Renesas R-Car MIPI CSI-2 receiver");
> +MODULE_LICENSE("GPL v2");

-- 
Regards,

Sakari Ailus
e-mail: sakari.ailus@iki.fi	XMPP: sailus@retiisi.org.uk

Re: [PATCH v7 2/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver driver

[Niklas Söderlund]

Hi Sakari,

Thanks for your comments.

On 2017-05-29 14:35:16 +0300, Sakari Ailus wrote:
> Hi Niklas,
> 
> A few comments below.
> 
> On Wed, May 24, 2017 at 02:13:53AM +0200, Niklas Söderlund wrote:
> > From: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> > 
> > A V4L2 driver for Renesas R-Car MIPI CSI-2 receiver. The driver
> > supports the rcar-vin driver on R-Car Gen3 SoCs where separate CSI-2
> > hardware blocks are connected between the video sources and the video
> > grabbers (VIN).
> > 
> > Driver is based on a prototype by Koji Matsuoka in the Renesas BSP.
> > 
> > Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> > ---
> >  drivers/media/platform/rcar-vin/Kconfig     |  12 +
> >  drivers/media/platform/rcar-vin/Makefile    |   1 +
> >  drivers/media/platform/rcar-vin/rcar-csi2.c | 867 ++++++++++++++++++++++++++++
> >  3 files changed, 880 insertions(+)
> >  create mode 100644 drivers/media/platform/rcar-vin/rcar-csi2.c
> > 
> > diff --git a/drivers/media/platform/rcar-vin/Kconfig b/drivers/media/platform/rcar-vin/Kconfig
> > index af4c98b44d2e22cb..6875f30c1ae42631 100644
> > --- a/drivers/media/platform/rcar-vin/Kconfig
> > +++ b/drivers/media/platform/rcar-vin/Kconfig
> > @@ -1,3 +1,15 @@
> > +config VIDEO_RCAR_CSI2
> > +	tristate "R-Car MIPI CSI-2 Receiver"
> > +	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && OF
> > +	depends on ARCH_RENESAS || COMPILE_TEST
> > +	select V4L2_FWNODE
> > +	---help---
> > +	  Support for Renesas R-Car MIPI CSI-2 receiver.
> > +	  Supports R-Car Gen3 SoCs.
> > +
> > +	  To compile this driver as a module, choose M here: the
> > +	  module will be called rcar-csi2.
> > +
> >  config VIDEO_RCAR_VIN
> >  	tristate "R-Car Video Input (VIN) Driver"
> >  	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && OF && HAS_DMA && MEDIA_CONTROLLER
> > diff --git a/drivers/media/platform/rcar-vin/Makefile b/drivers/media/platform/rcar-vin/Makefile
> > index 48c5632c21dc060b..5ab803d3e7c1aa57 100644
> > --- a/drivers/media/platform/rcar-vin/Makefile
> > +++ b/drivers/media/platform/rcar-vin/Makefile
> > @@ -1,3 +1,4 @@
> >  rcar-vin-objs = rcar-core.o rcar-dma.o rcar-v4l2.o
> >  
> > +obj-$(CONFIG_VIDEO_RCAR_CSI2) += rcar-csi2.o
> >  obj-$(CONFIG_VIDEO_RCAR_VIN) += rcar-vin.o
> > diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
> > new file mode 100644
> > index 0000000000000000..1175f1fe4b139a13
> > --- /dev/null
> > +++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
> > @@ -0,0 +1,867 @@
> > +/*
> > + * Driver for Renesas R-Car MIPI CSI-2 Receiver
> > + *
> > + * Copyright (C) 2017 Renesas Electronics Corp.
> > + *
> > + * This program is free software; you can redistribute  it and/or modify it
> > + * under  the terms of  the GNU General  Public License as published by the
> > + * Free Software Foundation;  either version 2 of the  License, or (at your
> > + * option) any later version.
> > + */
> > +
> > +#include <linux/delay.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/io.h>
> > +#include <linux/module.h>
> > +#include <linux/of.h>
> > +#include <linux/of_device.h>
> > +#include <linux/of_graph.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/pm_runtime.h>
> > +
> > +#include <media/v4l2-ctrls.h>
> > +#include <media/v4l2-device.h>
> > +#include <media/v4l2-fwnode.h>
> > +#include <media/v4l2-mc.h>
> > +#include <media/v4l2-subdev.h>
> > +
> > +/* Register offsets and bits */
> > +
> > +/* Control Timing Select */
> > +#define TREF_REG			0x00
> > +#define TREF_TREF			(1 << 0)
> > +
> > +/* Software Reset */
> > +#define SRST_REG			0x04
> > +#define SRST_SRST			(1 << 0)
> > +
> > +/* PHY Operation Control */
> > +#define PHYCNT_REG			0x08
> > +#define PHYCNT_SHUTDOWNZ		(1 << 17)
> > +#define PHYCNT_RSTZ			(1 << 16)
> > +#define PHYCNT_ENABLECLK		(1 << 4)
> > +#define PHYCNT_ENABLE_3			(1 << 3)
> > +#define PHYCNT_ENABLE_2			(1 << 2)
> > +#define PHYCNT_ENABLE_1			(1 << 1)
> > +#define PHYCNT_ENABLE_0			(1 << 0)
> > +
> > +/* Checksum Control */
> > +#define CHKSUM_REG			0x0c
> > +#define CHKSUM_ECC_EN			(1 << 1)
> > +#define CHKSUM_CRC_EN			(1 << 0)
> > +
> > +/*
> > + * Channel Data Type Select
> > + * VCDT[0-15]:  Channel 1 VCDT[16-31]:  Channel 2
> > + * VCDT2[0-15]: Channel 3 VCDT2[16-31]: Channel 4
> > + */
> > +#define VCDT_REG			0x10
> > +#define VCDT2_REG			0x14
> > +#define VCDT_VCDTN_EN			(1 << 15)
> > +#define VCDT_SEL_VC(n)			(((n) & 0x3) << 8)
> > +#define VCDT_SEL_DTN_ON			(1 << 6)
> > +#define VCDT_SEL_DT(n)			(((n) & 0x3f) << 0)
> > +
> > +/* Frame Data Type Select */
> > +#define FRDT_REG			0x18
> > +
> > +/* Field Detection Control */
> > +#define FLD_REG				0x1c
> > +#define FLD_FLD_NUM(n)			(((n) & 0xff) << 16)
> > +#define FLD_FLD_EN4			(1 << 3)
> > +#define FLD_FLD_EN3			(1 << 2)
> > +#define FLD_FLD_EN2			(1 << 1)
> > +#define FLD_FLD_EN			(1 << 0)
> > +
> > +/* Automatic Standby Control */
> > +#define ASTBY_REG			0x20
> > +
> > +/* Long Data Type Setting 0 */
> > +#define LNGDT0_REG			0x28
> > +
> > +/* Long Data Type Setting 1 */
> > +#define LNGDT1_REG			0x2c
> > +
> > +/* Interrupt Enable */
> > +#define INTEN_REG			0x30
> > +
> > +/* Interrupt Source Mask */
> > +#define INTCLOSE_REG			0x34
> > +
> > +/* Interrupt Status Monitor */
> > +#define INTSTATE_REG			0x38
> > +
> > +/* Interrupt Error Status Monitor */
> > +#define INTERRSTATE_REG			0x3c
> > +
> > +/* Short Packet Data */
> > +#define SHPDAT_REG			0x40
> > +
> > +/* Short Packet Count */
> > +#define SHPCNT_REG			0x44
> > +
> > +/* LINK Operation Control */
> > +#define LINKCNT_REG			0x48
> > +#define LINKCNT_MONITOR_EN		(1 << 31)
> > +#define LINKCNT_REG_MONI_PACT_EN	(1 << 25)
> > +#define LINKCNT_ICLK_NONSTOP		(1 << 24)
> > +
> > +/* Lane Swap */
> > +#define LSWAP_REG			0x4c
> > +#define LSWAP_L3SEL(n)			(((n) & 0x3) << 6)
> > +#define LSWAP_L2SEL(n)			(((n) & 0x3) << 4)
> > +#define LSWAP_L1SEL(n)			(((n) & 0x3) << 2)
> > +#define LSWAP_L0SEL(n)			(((n) & 0x3) << 0)
> > +
> > +/* PHY Test Interface Clear */
> > +#define PHTC_REG			0x58
> > +#define PHTC_TESTCLR			(1 << 0)
> > +
> > +/* PHY Frequency Control */
> > +#define PHYPLL_REG			0x68
> > +#define PHYPLL_HSFREQRANGE(n)		((n) << 16)
> > +
> > +struct phypll_hsfreqrange {
> > +	unsigned int	mbps;
> > +	unsigned char	reg;
> > +};
> > +
> > +static const struct phypll_hsfreqrange phypll_hsfreqrange_map[] = {
> > +	{ .mbps =   80,	.reg = 0x00 },
> > +	{ .mbps =   90,	.reg = 0x10 },
> > +	{ .mbps =  100,	.reg = 0x20 },
> > +	{ .mbps =  110,	.reg = 0x30 },
> > +	{ .mbps =  120,	.reg = 0x01 },
> > +	{ .mbps =  130,	.reg = 0x11 },
> > +	{ .mbps =  140,	.reg = 0x21 },
> > +	{ .mbps =  150,	.reg = 0x31 },
> > +	{ .mbps =  160,	.reg = 0x02 },
> > +	{ .mbps =  170,	.reg = 0x12 },
> > +	{ .mbps =  180,	.reg = 0x22 },
> > +	{ .mbps =  190,	.reg = 0x32 },
> > +	{ .mbps =  205,	.reg = 0x03 },
> > +	{ .mbps =  220,	.reg = 0x13 },
> > +	{ .mbps =  235,	.reg = 0x23 },
> > +	{ .mbps =  250,	.reg = 0x33 },
> > +	{ .mbps =  275,	.reg = 0x04 },
> > +	{ .mbps =  300,	.reg = 0x14 },
> > +	{ .mbps =  325,	.reg = 0x05 },
> > +	{ .mbps =  350,	.reg = 0x15 },
> > +	{ .mbps =  400,	.reg = 0x25 },
> > +	{ .mbps =  450,	.reg = 0x06 },
> > +	{ .mbps =  500,	.reg = 0x16 },
> > +	{ .mbps =  550,	.reg = 0x07 },
> > +	{ .mbps =  600,	.reg = 0x17 },
> > +	{ .mbps =  650,	.reg = 0x08 },
> > +	{ .mbps =  700,	.reg = 0x18 },
> > +	{ .mbps =  750,	.reg = 0x09 },
> > +	{ .mbps =  800,	.reg = 0x19 },
> > +	{ .mbps =  850,	.reg = 0x29 },
> > +	{ .mbps =  900,	.reg = 0x39 },
> > +	{ .mbps =  950,	.reg = 0x0A },
> > +	{ .mbps = 1000,	.reg = 0x1A },
> > +	{ .mbps = 1050,	.reg = 0x2A },
> > +	{ .mbps = 1100,	.reg = 0x3A },
> > +	{ .mbps = 1150,	.reg = 0x0B },
> > +	{ .mbps = 1200,	.reg = 0x1B },
> > +	{ .mbps = 1250,	.reg = 0x2B },
> > +	{ .mbps = 1300,	.reg = 0x3B },
> > +	{ .mbps = 1350,	.reg = 0x0C },
> > +	{ .mbps = 1400,	.reg = 0x1C },
> > +	{ .mbps = 1450,	.reg = 0x2C },
> > +	{ .mbps = 1500,	.reg = 0x3C },
> > +	/* guard */
> > +	{ .mbps =   0,	.reg = 0x00 },
> > +};
> > +
> > +/* PHY ESC Error Monitor */
> > +#define PHEERM_REG			0x74
> > +
> > +/* PHY Clock Lane Monitor */
> > +#define PHCLM_REG			0x78
> > +
> > +/* PHY Data Lane Monitor */
> > +#define PHDLM_REG			0x7c
> > +
> > +struct rcar_csi2_format {
> > +	unsigned int code;
> > +	unsigned int datatype;
> > +	unsigned int bpp;
> > +};
> > +
> > +static const struct rcar_csi2_format rcar_csi2_formats[] = {
> > +	{ .code = MEDIA_BUS_FMT_RGB888_1X24,	.datatype = 0x24, .bpp = 24},
> > +	{ .code = MEDIA_BUS_FMT_UYVY8_1X16,	.datatype = 0x1e, .bpp = 8 },
> > +	{ .code = MEDIA_BUS_FMT_UYVY8_2X8,	.datatype = 0x1e, .bpp = 8 },
> > +	{ .code = MEDIA_BUS_FMT_YUYV10_2X10,	.datatype = 0x1e, .bpp = 8 },
> > +};
> > +
> > +static const struct rcar_csi2_format *rcar_csi2_code_to_fmt(unsigned int code)
> > +{
> > +	int i;
> > +
> > +	for (i = 0; i < ARRAY_SIZE(rcar_csi2_formats); i++)
> > +		if (rcar_csi2_formats[i].code == code)
> > +			return rcar_csi2_formats + i;
> > +	return NULL;
> > +}
> > +
> > +enum rcar_csi2_pads {
> > +	RCAR_CSI2_SINK,
> > +	RCAR_CSI2_SOURCE_VC0,
> > +	RCAR_CSI2_SOURCE_VC1,
> > +	RCAR_CSI2_SOURCE_VC2,
> > +	RCAR_CSI2_SOURCE_VC3,
> > +	NR_OF_RCAR_CSI2_PAD,
> > +};
> > +
> > +struct rcar_csi2 {
> > +	struct device *dev;
> > +	void __iomem *base;
> > +
> > +	unsigned short lanes;
> > +	unsigned char lane_swap[4];
> > +
> > +	struct v4l2_subdev subdev;
> > +	struct media_pad pads[NR_OF_RCAR_CSI2_PAD];
> > +
> > +	struct v4l2_mbus_framefmt mf;
> > +
> > +	struct mutex lock;
> > +	int stream_count;
> > +
> > +	struct v4l2_async_notifier notifier;
> > +	struct {
> > +		struct v4l2_async_subdev asd;
> > +		struct v4l2_subdev *subdev;
> > +		struct fwnode_handle *fwnode;
> > +		unsigned int source_pad;
> > +	} remote;
> > +};
> > +
> > +static inline struct rcar_csi2 *sd_to_csi2(struct v4l2_subdev *sd)
> > +{
> > +	return container_of(sd, struct rcar_csi2, subdev);
> > +}
> > +
> > +static u32 rcar_csi2_read(struct rcar_csi2 *priv, unsigned int reg)
> > +{
> > +	return ioread32(priv->base + reg);
> > +}
> > +
> > +static void rcar_csi2_write(struct rcar_csi2 *priv, unsigned int reg, u32 data)
> > +{
> > +	iowrite32(data, priv->base + reg);
> > +}
> > +
> > +static void rcar_csi2_reset(struct rcar_csi2 *priv)
> > +{
> > +	rcar_csi2_write(priv, SRST_REG, SRST_SRST);
> > +	rcar_csi2_write(priv, SRST_REG, 0);
> > +}
> > +
> > +static int rcar_csi2_wait_phy_start(struct rcar_csi2 *priv)
> > +{
> > +	int timeout;
> > +
> > +	/* Wait for the clock and data lanes to enter LP-11 state. */
> > +	for (timeout = 100; timeout >= 0; timeout--) {
> > +		const u32 lane_mask = (1 << priv->lanes) - 1;
> > +
> > +		if ((rcar_csi2_read(priv, PHCLM_REG) & 1) == 1 &&
> > +		    (rcar_csi2_read(priv, PHDLM_REG) & lane_mask) == lane_mask)
> > +			return 0;
> > +
> > +		msleep(20);
> > +	}
> > +
> > +	dev_err(priv->dev, "Timeout waiting for LP-11 state\n");
> > +
> > +	return -ETIMEDOUT;
> > +}
> > +
> > +static int rcar_csi2_calc_phypll(struct rcar_csi2 *priv,
> > +				 struct v4l2_subdev *source,
> > +				 struct v4l2_mbus_framefmt *mf,
> > +				 u32 *phypll)
> > +{
> > +	const struct phypll_hsfreqrange *hsfreq;
> > +	const struct rcar_csi2_format *format;
> > +	struct v4l2_ext_controls ctrls;
> > +	struct v4l2_ext_control ctrl;
> > +	u64 mbps;
> > +	int ret;
> > +
> > +	memset(&ctrls, 0, sizeof(ctrls));
> > +	memset(&ctrl, 0, sizeof(ctrl));
> > +
> > +	ctrl.id = V4L2_CID_PIXEL_RATE;
> > +
> > +	ctrls.count = 1;
> > +	ctrls.controls = &ctrl;
> > +
> > +	ret = v4l2_g_ext_ctrls(source->ctrl_handler, &ctrls);
> 
> v4l2_ctrl_g_ctrl_int64(), please. Or do I miss something?

Thanks will fix.

> 
> > +	if (ret < 0) {
> > +		dev_err(priv->dev, "no link freq control in subdev %s\n",
> > +			source->name);
> > +		return ret;
> > +	}
> > +
> > +	format = rcar_csi2_code_to_fmt(mf->code);
> > +	if (!format) {
> > +		dev_err(priv->dev, "Unknown format: %d\n", mf->code);
> > +		return -EINVAL;
> > +	}
> > +
> > +	mbps = ctrl.value64 * format->bpp;
> > +	do_div(mbps, priv->lanes * 1000000);
> > +
> > +	for (hsfreq = phypll_hsfreqrange_map; hsfreq->mbps != 0; hsfreq++)
> > +		if (hsfreq->mbps >= mbps)
> > +			break;
> > +
> > +	if (!hsfreq->mbps) {
> > +		dev_err(priv->dev, "Unsupported PHY speed (%llu Mbps)", mbps);
> > +		return -ERANGE;
> > +	}
> > +
> > +	dev_dbg(priv->dev, "PHY HSFREQRANGE requested %llu got %u Mbps\n", mbps,
> > +		hsfreq->mbps);
> > +
> > +	*phypll = PHYPLL_HSFREQRANGE(hsfreq->reg);
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_start(struct rcar_csi2 *priv)
> > +{
> > +	const struct rcar_csi2_format *format;
> > +	struct v4l2_subdev_format fmt;
> > +	struct media_pad *source_pad;
> > +	struct v4l2_subdev *source = NULL;
> > +	struct v4l2_mbus_framefmt *mf = &fmt.format;
> > +	u32 phycnt, phypll, tmp;
> > +	u32 vcdt = 0, vcdt2 = 0;
> > +	unsigned int i;
> > +	int ret;
> > +
> > +	source_pad =
> > +		media_entity_remote_pad(&priv->subdev.entity.pads[RCAR_CSI2_SINK]);
> 
> Over 80 characters per line. I think you could split this up differently.

Will fix.

> 
> > +	if (!source_pad) {
> > +		dev_err(priv->dev, "Could not find remote source pad\n");
> > +		return -ENODEV;
> > +	}
> > +
> > +	source = media_entity_to_v4l2_subdev(source_pad->entity);
> > +	if (!source) {
> > +		dev_err(priv->dev, "Could not find remote subdevice\n");
> > +		return -ENODEV;
> > +	}
> > +
> > +	dev_dbg(priv->dev, "Using source %s pad: %u\n", source->name,
> > +		source_pad->index);
> > +
> > +	fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
> > +	fmt.pad = source_pad->index;
> > +	ret = v4l2_subdev_call(source, pad, get_fmt, NULL, &fmt);
> > +	if (ret)
> > +		return ret;
> > +
> > +	dev_dbg(priv->dev, "Input size (%dx%d%c)\n", mf->width,
> > +		mf->height, mf->field == V4L2_FIELD_NONE ? 'p' : 'i');
> > +
> > +	/*
> > +	 * Enable all Virtual Channels
> > +	 *
> > +	 * NOTE: I'ts not possible to get individual format for each
> 
> "It's"

Ops.. will fix :-)

> 
> > +	 *       source virtual channel. Once this is possible in V4L2
> > +	 *       it should be used here.
> > +	 */
> > +	for (i = 0; i < 4; i++) {
> > +
> > +		format = rcar_csi2_code_to_fmt(mf->code);
> > +		if (!format) {
> > +			dev_err(priv->dev, "Unsupported media bus format: %d\n",
> > +				mf->code);
> > +			return -EINVAL;
> > +		}
> > +
> > +		tmp = VCDT_SEL_VC(i) | VCDT_VCDTN_EN | VCDT_SEL_DTN_ON |
> > +			VCDT_SEL_DT(format->datatype);
> > +
> > +		/* Store in correct reg and offset */
> > +		if (i < 2)
> > +			vcdt |= tmp << ((i % 2) * 16);
> > +		else
> > +			vcdt2 |= tmp << ((i % 2) * 16);
> > +	}
> > +
> > +	switch (priv->lanes) {
> > +	case 1:
> > +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_0;
> > +		break;
> > +	case 2:
> > +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_1 | PHYCNT_ENABLE_0;
> > +		break;
> > +	case 4:
> > +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_3 | PHYCNT_ENABLE_2 |
> > +			PHYCNT_ENABLE_1 | PHYCNT_ENABLE_0;
> > +		break;
> > +	default:
> > +		return -EINVAL;
> > +	}
> > +
> > +	ret = rcar_csi2_calc_phypll(priv, source, mf, &phypll);
> > +	if (ret)
> > +		return ret;
> > +
> > +	/* Init */
> > +	rcar_csi2_write(priv, TREF_REG, TREF_TREF);
> > +	rcar_csi2_reset(priv);
> > +	rcar_csi2_write(priv, PHTC_REG, 0);
> > +
> > +	/* Configure */
> > +	rcar_csi2_write(priv, FLD_REG, FLD_FLD_NUM(2) | FLD_FLD_EN4 |
> > +			FLD_FLD_EN3 | FLD_FLD_EN2 | FLD_FLD_EN);
> > +	rcar_csi2_write(priv, VCDT_REG, vcdt);
> > +	rcar_csi2_write(priv, VCDT2_REG, vcdt2);
> > +	/* Lanes are zero indexed */
> > +	rcar_csi2_write(priv, LSWAP_REG,
> > +			LSWAP_L0SEL(priv->lane_swap[0] - 1) |
> > +			LSWAP_L1SEL(priv->lane_swap[1] - 1) |
> > +			LSWAP_L2SEL(priv->lane_swap[2] - 1) |
> > +			LSWAP_L3SEL(priv->lane_swap[3] - 1));
> 
> How are the lanes numbered?

In the datasheet they are numbered CSIn_DATA{0,1,2,3}.

> 
> Do you have a fixed number of lanes per receiver?

Two different configurations exists a 4-lane CSI-2 receiver and a 2-lane 
CSI-2 receiver.

> 
> > +
> > +	/* Start */
> > +	rcar_csi2_write(priv, PHYPLL_REG, phypll);
> > +	rcar_csi2_write(priv, PHYCNT_REG, phycnt);
> > +	rcar_csi2_write(priv, LINKCNT_REG, LINKCNT_MONITOR_EN |
> > +			LINKCNT_REG_MONI_PACT_EN | LINKCNT_ICLK_NONSTOP);
> > +	rcar_csi2_write(priv, PHYCNT_REG, phycnt | PHYCNT_SHUTDOWNZ);
> > +	rcar_csi2_write(priv, PHYCNT_REG, phycnt | PHYCNT_SHUTDOWNZ |
> > +			PHYCNT_RSTZ);
> > +
> > +	return rcar_csi2_wait_phy_start(priv);
> > +}
> > +
> > +static void rcar_csi2_stop(struct rcar_csi2 *priv)
> > +{
> > +	rcar_csi2_write(priv, PHYCNT_REG, 0);
> > +
> > +	rcar_csi2_reset(priv);
> > +}
> > +
> > +static int rcar_csi2_sd_info(struct rcar_csi2 *priv, struct v4l2_subdev **sd)
> > +{
> > +	struct media_pad *pad;
> > +
> > +	pad = media_entity_remote_pad(&priv->pads[RCAR_CSI2_SINK]);
> > +	if (!pad) {
> > +		dev_err(priv->dev, "Could not find remote pad\n");
> > +		return -ENODEV;
> > +	}
> > +
> > +	*sd = media_entity_to_v4l2_subdev(pad->entity);
> > +	if (!*sd) {
> > +		dev_err(priv->dev, "Could not find remote subdevice\n");
> > +		return -ENODEV;
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_s_stream(struct v4l2_subdev *sd, int enable)
> > +{
> > +	struct rcar_csi2 *priv = sd_to_csi2(sd);
> > +	struct v4l2_subdev *nextsd;
> > +	int ret;
> > +
> > +	mutex_lock(&priv->lock);
> > +
> > +	ret = rcar_csi2_sd_info(priv, &nextsd);
> > +	if (ret)
> > +		goto out;
> > +
> > +	priv->stream_count += enable ? 1 : -1;
> > +
> > +	if (enable && priv->stream_count == 1) {
> > +		ret =  rcar_csi2_start(priv);
> > +		if (ret)
> > +			goto out;
> > +		ret = v4l2_subdev_call(nextsd, video, s_stream, 1);
> > +
> > +	} else if (!enable && !priv->stream_count) {
> > +		rcar_csi2_stop(priv);
> > +		ret = v4l2_subdev_call(nextsd, video, s_stream, 0);
> > +	}
> > +out:
> > +	mutex_unlock(&priv->lock);
> > +
> > +	return ret;
> > +}
> > +
> > +static int rcar_csi2_s_power(struct v4l2_subdev *sd, int on)
> > +{
> > +	struct rcar_csi2 *priv = sd_to_csi2(sd);
> > +
> > +	if (on)
> > +		pm_runtime_get_sync(priv->dev);
> > +	else
> > +		pm_runtime_put(priv->dev);
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_set_pad_format(struct v4l2_subdev *sd,
> > +				    struct v4l2_subdev_pad_config *cfg,
> > +				    struct v4l2_subdev_format *format)
> > +{
> > +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> > +
> > +	if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE)
> > +		priv->mf = format->format;
> 
> How about the try formats? E.g.
> 
> *v4l2_subdev_get_try_format() = format->fmt;

Thanks will fix.

> 
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_get_pad_format(struct v4l2_subdev *sd,
> > +				    struct v4l2_subdev_pad_config *cfg,
> > +				    struct v4l2_subdev_format *format)
> > +{
> > +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> > +
> > +	format->format = priv->mf;
> 
> Ditto.

Ditto :-)

> 
> > +
> > +	return 0;
> > +}
> > +
> > +static const struct v4l2_subdev_video_ops rcar_csi2_video_ops = {
> > +	.s_stream = rcar_csi2_s_stream,
> > +};
> > +
> > +static const struct v4l2_subdev_core_ops rcar_csi2_subdev_core_ops = {
> > +	.s_power = rcar_csi2_s_power,
> > +};
> > +
> > +static const struct v4l2_subdev_pad_ops rcar_csi2_pad_ops = {
> > +	.set_fmt = rcar_csi2_set_pad_format,
> > +	.get_fmt = rcar_csi2_get_pad_format,
> > +};
> > +
> > +static const struct v4l2_subdev_ops rcar_csi2_subdev_ops = {
> > +	.video	= &rcar_csi2_video_ops,
> > +	.core	= &rcar_csi2_subdev_core_ops,
> > +	.pad	= &rcar_csi2_pad_ops,
> > +};
> > +
> > +/* -----------------------------------------------------------------------------
> > + * Async and registered of subdevices and links
> > + */
> > +
> > +#define notifier_to_priv(n) container_of(n, struct rcar_csi2, notifier)
> > +
> > +static int rcar_csi2_notify_complete(struct v4l2_async_notifier *notifier)
> > +{
> > +	struct rcar_csi2 *priv = notifier_to_priv(notifier);
> > +	int ret;
> > +
> > +	ret = v4l2_device_register_subdev_nodes(priv->subdev.v4l2_dev);
> > +	if (ret) {
> > +		dev_err(priv->dev, "Failed to register subdev nodes\n");
> > +		return ret;
> > +	}
> > +
> > +	return media_create_pad_link(&priv->remote.subdev->entity,
> > +				     priv->remote.source_pad,
> > +				     &priv->subdev.entity, 0,
> > +				     MEDIA_LNK_FL_ENABLED |
> > +				     MEDIA_LNK_FL_IMMUTABLE);
> > +}
> > +
> > +static int rcar_csi2_notify_bound(struct v4l2_async_notifier *notifier,
> > +				   struct v4l2_subdev *subdev,
> > +				   struct v4l2_async_subdev *asd)
> > +{
> > +	struct rcar_csi2 *priv = notifier_to_priv(notifier);
> > +	int ret;
> > +
> > +	v4l2_set_subdev_hostdata(subdev, priv);
> > +
> > +	ret = media_entity_pad_from_fwnode(&subdev->entity,
> > +					   priv->remote.fwnode,
> > +					   MEDIA_PAD_FL_SOURCE,
> > +					   &priv->remote.source_pad);
> > +	if (ret) {
> > +		dev_err(priv->dev, "Failed to find pad for %s\n",
> > +			subdev->name);
> > +		return ret;
> > +	}
> > +
> > +	dev_dbg(priv->dev, "Bound %s pad: %d\n", subdev->name,
> > +		priv->remote.source_pad);
> > +	priv->remote.subdev = subdev;
> > +
> > +	return 0;
> > +}
> 
> A newline would be nice here.

Yes.

> 
> > +static void rcar_csi2_notify_unbind(struct v4l2_async_notifier *notifier,
> > +				     struct v4l2_subdev *subdev,
> > +				     struct v4l2_async_subdev *asd)
> > +{
> > +	struct rcar_csi2 *priv = notifier_to_priv(notifier);
> > +
> > +	dev_dbg(priv->dev, "Unbind %s\n", subdev->name);
> > +	priv->remote.subdev = NULL;
> > +}
> > +
> > +static int rcar_csi2_registered(struct v4l2_subdev *sd)
> > +{
> > +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> > +	struct v4l2_async_subdev **subdevs = NULL;
> > +	int ret;
> > +
> > +	subdevs = devm_kzalloc(priv->dev, sizeof(*subdevs), GFP_KERNEL);
> > +	if (subdevs == NULL)
> > +		return -ENOMEM;
> > +
> > +	subdevs[0] = &priv->remote.asd;
> > +
> > +	priv->notifier.num_subdevs = 1;
> > +	priv->notifier.subdevs = subdevs;
> > +	priv->notifier.bound = rcar_csi2_notify_bound;
> > +	priv->notifier.unbind = rcar_csi2_notify_unbind;
> > +	priv->notifier.complete = rcar_csi2_notify_complete;
> > +
> > +	ret = v4l2_async_subnotifier_register(&priv->subdev, &priv->notifier);
> > +	if (ret < 0) {
> > +		dev_err(priv->dev, "Notifier registration failed\n");
> > +		return ret;
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static void rcar_csi2_unregistered(struct v4l2_subdev *sd)
> > +{
> > +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> > +
> > +	v4l2_async_subnotifier_unregister(&priv->notifier);
> > +}
> > +
> > +static const struct v4l2_subdev_internal_ops rcar_csi2_internal_ops = {
> > +	.registered = rcar_csi2_registered,
> > +	.unregistered = rcar_csi2_unregistered,
> > +};
> > +
> > +static int rcar_csi2_parse_dt_subdevice(struct rcar_csi2 *priv)
> > +{
> > +	struct device_node *remote, *ep;
> > +	struct v4l2_fwnode_endpoint v4l2_ep;
> > +	int ret;
> > +
> > +	ep = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0);
> > +	if (!ep) {
> > +		dev_err(priv->dev, "Not connected to subdevice\n");
> > +		return -EINVAL;
> > +	}
> > +
> > +	ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &v4l2_ep);
> > +	if (ret) {
> > +		dev_err(priv->dev, "Could not parse v4l2 endpoint\n");
> > +		of_node_put(ep);
> > +		return -EINVAL;
> > +	}
> > +
> > +	if (v4l2_ep.bus_type != V4L2_MBUS_CSI2) {
> > +		dev_err(priv->dev, "Unknown media bus type: 0x%x\n",
> > +			v4l2_ep.bus_type);
> > +		of_node_put(ep);
> > +		return -EINVAL;
> > +	}
> > +
> > +	priv->remote.fwnode =
> > +		fwnode_graph_get_remote_endpoint(of_fwnode_handle(ep));
> > +
> > +	remote = of_graph_get_remote_port_parent(ep);
> > +	of_node_put(ep);
> > +	if (!remote) {
> > +		dev_err(priv->dev, "No subdevice found for endpoint '%s'\n",
> > +			of_node_full_name(ep));
> > +		return -EINVAL;
> > +	}
> > +
> > +	priv->remote.asd.match.fwnode.fwnode = of_fwnode_handle(remote);
> > +	priv->remote.asd.match_type = V4L2_ASYNC_MATCH_FWNODE;
> > +
> > +	dev_dbg(priv->dev, "Found '%s'\n", of_node_full_name(remote));
> > +
> > +	return 0;
> > +}
> > +
> > +/* -----------------------------------------------------------------------------
> > + * Platform Device Driver
> > + */
> > +
> > +static const struct of_device_id rcar_csi2_of_table[] = {
> > +	{ .compatible = "renesas,rcar-gen3-csi2" },
> > +	{ },
> > +};
> > +MODULE_DEVICE_TABLE(of, rcar_csi2_of_table);
> > +
> > +static const struct media_entity_operations rcar_csi2_entity_ops = {
> > +	.link_validate = v4l2_subdev_link_validate,
> > +};
> > +
> > +static int rcar_csi2_parse_dt_settings(struct rcar_csi2 *priv)
> > +{
> > +	struct v4l2_fwnode_endpoint v4l2_ep;
> > +	struct device_node *ep;
> > +	unsigned int i;
> > +	int ret;
> > +
> > +	ep = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0);
> > +	if (!ep)
> > +		return -EINVAL;
> > +
> > +	ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &v4l2_ep);
> > +	of_node_put(ep);
> > +	if (ret) {
> > +		dev_err(priv->dev, "Could not parse v4l2 endpoint\n");
> > +		return -EINVAL;
> > +	}
> > +
> > +	if (v4l2_ep.bus_type != V4L2_MBUS_CSI2) {
> > +		dev_err(priv->dev, "Unsupported media bus type for %s\n",
> > +			of_node_full_name(ep));
> > +		return -EINVAL;
> > +	}
> > +
> > +	priv->lanes = v4l2_ep.bus.mipi_csi2.num_data_lanes;
> > +	if (priv->lanes != 1 && priv->lanes != 2 && priv->lanes != 4) {
> > +		dev_err(priv->dev, "Unsupported number of data-lanes: %d\n",
> > +			priv->lanes);
> > +		return -EINVAL;
> > +	}
> > +
> > +	for (i = 0; i < ARRAY_SIZE(priv->lane_swap); i++) {
> > +		priv->lane_swap[i] = i < priv->lanes ?
> > +			v4l2_ep.bus.mipi_csi2.data_lanes[i] : i;
> > +
> > +		/* Check for valid lane number */
> > +		if (priv->lane_swap[i] < 1 || priv->lane_swap[i] > 4) {
> 
> Do you also support for three lanes? Based on the code elsewhere, it doesn't
> seem like that.

Yes 3-lanes should be supported but I have no way of testing this. But I 
do belive the code is prepared to handle it, see for example in the 
driver all logic around priv->lanes variable, am I missing something?

> 
> > +			dev_err(priv->dev, "data-lanes must be in 1-4 range\n");
> > +			return -EINVAL;
> > +		}
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_probe_resources(struct rcar_csi2 *priv,
> > +				     struct platform_device *pdev)
> > +{
> > +	struct resource *mem;
> > +	int irq;
> > +
> > +	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > +	if (!mem)
> > +		return -ENODEV;
> > +
> > +	priv->base = devm_ioremap_resource(&pdev->dev, mem);
> > +	if (IS_ERR(priv->base))
> > +		return PTR_ERR(priv->base);
> > +
> > +	irq = platform_get_irq(pdev, 0);
> > +	if (irq < 0)
> > +		return irq;
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_probe(struct platform_device *pdev)
> > +{
> > +	struct rcar_csi2 *priv;
> > +	unsigned int i;
> > +	int ret;
> > +
> > +	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
> > +	if (!priv)
> > +		return -ENOMEM;
> > +
> > +	priv->dev = &pdev->dev;
> > +
> > +	mutex_init(&priv->lock);
> > +	priv->stream_count = 0;
> > +
> > +	ret = rcar_csi2_parse_dt_settings(priv);
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = rcar_csi2_parse_dt_subdevice(priv);
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = rcar_csi2_probe_resources(priv, pdev);
> > +	if (ret) {
> > +		dev_err(priv->dev, "Failed to get resources\n");
> > +		return ret;
> > +	}
> > +
> > +	platform_set_drvdata(pdev, priv);
> > +
> > +	priv->subdev.owner = THIS_MODULE;
> > +	priv->subdev.dev = &pdev->dev;
> > +	v4l2_subdev_init(&priv->subdev, &rcar_csi2_subdev_ops);
> > +	v4l2_set_subdevdata(&priv->subdev, &pdev->dev);
> > +	snprintf(priv->subdev.name, V4L2_SUBDEV_NAME_SIZE, "%s %s",
> > +		 KBUILD_MODNAME, dev_name(&pdev->dev));
> > +	priv->subdev.flags = V4L2_SUBDEV_FL_HAS_DEVNODE;
> > +	priv->subdev.internal_ops = &rcar_csi2_internal_ops;
> > +
> > +	priv->subdev.entity.function = MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER;
> > +	priv->subdev.entity.ops = &rcar_csi2_entity_ops;
> > +
> > +	priv->pads[RCAR_CSI2_SINK].flags = MEDIA_PAD_FL_SINK;
> > +	for (i = RCAR_CSI2_SOURCE_VC0; i < NR_OF_RCAR_CSI2_PAD; i++)
> > +		priv->pads[i].flags = MEDIA_PAD_FL_SOURCE;
> > +
> > +	ret = media_entity_pads_init(&priv->subdev.entity, NR_OF_RCAR_CSI2_PAD,
> > +				     priv->pads);
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = v4l2_async_register_subdev(&priv->subdev);
> > +	if (ret < 0)
> > +		return ret;
> > +
> > +	pm_runtime_enable(&pdev->dev);
> > +
> > +	dev_info(priv->dev, "%d lanes found\n", priv->lanes);
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_remove(struct platform_device *pdev)
> > +{
> > +	struct rcar_csi2 *priv = platform_get_drvdata(pdev);
> > +
> > +	v4l2_async_unregister_subdev(&priv->subdev);
> > +
> > +	pm_runtime_disable(&pdev->dev);
> > +
> > +	return 0;
> > +}
> > +
> > +static struct platform_driver __refdata rcar_csi2_pdrv = {
> > +	.remove	= rcar_csi2_remove,
> > +	.probe	= rcar_csi2_probe,
> > +	.driver	= {
> > +		.name	= "rcar-csi2",
> > +		.of_match_table	= of_match_ptr(rcar_csi2_of_table),
> > +	},
> > +};
> > +
> > +module_platform_driver(rcar_csi2_pdrv);
> > +
> > +MODULE_AUTHOR("Niklas Söderlund <niklas.soderlund@ragnatech.se>");
> > +MODULE_DESCRIPTION("Renesas R-Car MIPI CSI-2 receiver");
> > +MODULE_LICENSE("GPL v2");
> 
> -- 
> Regards,
> 
> Sakari Ailus
> e-mail: sakari.ailus@iki.fi	XMPP: sailus@retiisi.org.uk

-- 
Regards,
Niklas Söderlund

Re: [PATCH v7 2/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver driver

[Niklas Söderlund]

Hi Sakari,

Thanks for your comments.

On 2017-05-29 14:35:16 +0300, Sakari Ailus wrote:
> Hi Niklas,
> 
> A few comments below.
> 
> On Wed, May 24, 2017 at 02:13:53AM +0200, Niklas S�derlund wrote:
> > From: Niklas S�derlund <niklas.soderlund+renesas@ragnatech.se>
> > 
> > A V4L2 driver for Renesas R-Car MIPI CSI-2 receiver. The driver
> > supports the rcar-vin driver on R-Car Gen3 SoCs where separate CSI-2
> > hardware blocks are connected between the video sources and the video
> > grabbers (VIN).
> > 
> > Driver is based on a prototype by Koji Matsuoka in the Renesas BSP.
> > 
> > Signed-off-by: Niklas S�derlund <niklas.soderlund+renesas@ragnatech.se>
> > ---
> >  drivers/media/platform/rcar-vin/Kconfig     |  12 +
> >  drivers/media/platform/rcar-vin/Makefile    |   1 +
> >  drivers/media/platform/rcar-vin/rcar-csi2.c | 867 ++++++++++++++++++++++++++++
> >  3 files changed, 880 insertions(+)
> >  create mode 100644 drivers/media/platform/rcar-vin/rcar-csi2.c
> > 
> > diff --git a/drivers/media/platform/rcar-vin/Kconfig b/drivers/media/platform/rcar-vin/Kconfig
> > index af4c98b44d2e22cb..6875f30c1ae42631 100644
> > --- a/drivers/media/platform/rcar-vin/Kconfig
> > +++ b/drivers/media/platform/rcar-vin/Kconfig
> > @@ -1,3 +1,15 @@
> > +config VIDEO_RCAR_CSI2
> > +	tristate "R-Car MIPI CSI-2 Receiver"
> > +	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && OF
> > +	depends on ARCH_RENESAS || COMPILE_TEST
> > +	select V4L2_FWNODE
> > +	---help---
> > +	  Support for Renesas R-Car MIPI CSI-2 receiver.
> > +	  Supports R-Car Gen3 SoCs.
> > +
> > +	  To compile this driver as a module, choose M here: the
> > +	  module will be called rcar-csi2.
> > +
> >  config VIDEO_RCAR_VIN
> >  	tristate "R-Car Video Input (VIN) Driver"
> >  	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && OF && HAS_DMA && MEDIA_CONTROLLER
> > diff --git a/drivers/media/platform/rcar-vin/Makefile b/drivers/media/platform/rcar-vin/Makefile
> > index 48c5632c21dc060b..5ab803d3e7c1aa57 100644
> > --- a/drivers/media/platform/rcar-vin/Makefile
> > +++ b/drivers/media/platform/rcar-vin/Makefile
> > @@ -1,3 +1,4 @@
> >  rcar-vin-objs = rcar-core.o rcar-dma.o rcar-v4l2.o
> >  
> > +obj-$(CONFIG_VIDEO_RCAR_CSI2) += rcar-csi2.o
> >  obj-$(CONFIG_VIDEO_RCAR_VIN) += rcar-vin.o
> > diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
> > new file mode 100644
> > index 0000000000000000..1175f1fe4b139a13
> > --- /dev/null
> > +++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
> > @@ -0,0 +1,867 @@
> > +/*
> > + * Driver for Renesas R-Car MIPI CSI-2 Receiver
> > + *
> > + * Copyright (C) 2017 Renesas Electronics Corp.
> > + *
> > + * This program is free software; you can redistribute  it and/or modify it
> > + * under  the terms of  the GNU General  Public License as published by the
> > + * Free Software Foundation;  either version 2 of the  License, or (at your
> > + * option) any later version.
> > + */
> > +
> > +#include <linux/delay.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/io.h>
> > +#include <linux/module.h>
> > +#include <linux/of.h>
> > +#include <linux/of_device.h>
> > +#include <linux/of_graph.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/pm_runtime.h>
> > +
> > +#include <media/v4l2-ctrls.h>
> > +#include <media/v4l2-device.h>
> > +#include <media/v4l2-fwnode.h>
> > +#include <media/v4l2-mc.h>
> > +#include <media/v4l2-subdev.h>
> > +
> > +/* Register offsets and bits */
> > +
> > +/* Control Timing Select */
> > +#define TREF_REG			0x00
> > +#define TREF_TREF			(1 << 0)
> > +
> > +/* Software Reset */
> > +#define SRST_REG			0x04
> > +#define SRST_SRST			(1 << 0)
> > +
> > +/* PHY Operation Control */
> > +#define PHYCNT_REG			0x08
> > +#define PHYCNT_SHUTDOWNZ		(1 << 17)
> > +#define PHYCNT_RSTZ			(1 << 16)
> > +#define PHYCNT_ENABLECLK		(1 << 4)
> > +#define PHYCNT_ENABLE_3			(1 << 3)
> > +#define PHYCNT_ENABLE_2			(1 << 2)
> > +#define PHYCNT_ENABLE_1			(1 << 1)
> > +#define PHYCNT_ENABLE_0			(1 << 0)
> > +
> > +/* Checksum Control */
> > +#define CHKSUM_REG			0x0c
> > +#define CHKSUM_ECC_EN			(1 << 1)
> > +#define CHKSUM_CRC_EN			(1 << 0)
> > +
> > +/*
> > + * Channel Data Type Select
> > + * VCDT[0-15]:  Channel 1 VCDT[16-31]:  Channel 2
> > + * VCDT2[0-15]: Channel 3 VCDT2[16-31]: Channel 4
> > + */
> > +#define VCDT_REG			0x10
> > +#define VCDT2_REG			0x14
> > +#define VCDT_VCDTN_EN			(1 << 15)
> > +#define VCDT_SEL_VC(n)			(((n) & 0x3) << 8)
> > +#define VCDT_SEL_DTN_ON			(1 << 6)
> > +#define VCDT_SEL_DT(n)			(((n) & 0x3f) << 0)
> > +
> > +/* Frame Data Type Select */
> > +#define FRDT_REG			0x18
> > +
> > +/* Field Detection Control */
> > +#define FLD_REG				0x1c
> > +#define FLD_FLD_NUM(n)			(((n) & 0xff) << 16)
> > +#define FLD_FLD_EN4			(1 << 3)
> > +#define FLD_FLD_EN3			(1 << 2)
> > +#define FLD_FLD_EN2			(1 << 1)
> > +#define FLD_FLD_EN			(1 << 0)
> > +
> > +/* Automatic Standby Control */
> > +#define ASTBY_REG			0x20
> > +
> > +/* Long Data Type Setting 0 */
> > +#define LNGDT0_REG			0x28
> > +
> > +/* Long Data Type Setting 1 */
> > +#define LNGDT1_REG			0x2c
> > +
> > +/* Interrupt Enable */
> > +#define INTEN_REG			0x30
> > +
> > +/* Interrupt Source Mask */
> > +#define INTCLOSE_REG			0x34
> > +
> > +/* Interrupt Status Monitor */
> > +#define INTSTATE_REG			0x38
> > +
> > +/* Interrupt Error Status Monitor */
> > +#define INTERRSTATE_REG			0x3c
> > +
> > +/* Short Packet Data */
> > +#define SHPDAT_REG			0x40
> > +
> > +/* Short Packet Count */
> > +#define SHPCNT_REG			0x44
> > +
> > +/* LINK Operation Control */
> > +#define LINKCNT_REG			0x48
> > +#define LINKCNT_MONITOR_EN		(1 << 31)
> > +#define LINKCNT_REG_MONI_PACT_EN	(1 << 25)
> > +#define LINKCNT_ICLK_NONSTOP		(1 << 24)
> > +
> > +/* Lane Swap */
> > +#define LSWAP_REG			0x4c
> > +#define LSWAP_L3SEL(n)			(((n) & 0x3) << 6)
> > +#define LSWAP_L2SEL(n)			(((n) & 0x3) << 4)
> > +#define LSWAP_L1SEL(n)			(((n) & 0x3) << 2)
> > +#define LSWAP_L0SEL(n)			(((n) & 0x3) << 0)
> > +
> > +/* PHY Test Interface Clear */
> > +#define PHTC_REG			0x58
> > +#define PHTC_TESTCLR			(1 << 0)
> > +
> > +/* PHY Frequency Control */
> > +#define PHYPLL_REG			0x68
> > +#define PHYPLL_HSFREQRANGE(n)		((n) << 16)
> > +
> > +struct phypll_hsfreqrange {
> > +	unsigned int	mbps;
> > +	unsigned char	reg;
> > +};
> > +
> > +static const struct phypll_hsfreqrange phypll_hsfreqrange_map[] = {
> > +	{ .mbps =   80,	.reg = 0x00 },
> > +	{ .mbps =   90,	.reg = 0x10 },
> > +	{ .mbps =  100,	.reg = 0x20 },
> > +	{ .mbps =  110,	.reg = 0x30 },
> > +	{ .mbps =  120,	.reg = 0x01 },
> > +	{ .mbps =  130,	.reg = 0x11 },
> > +	{ .mbps =  140,	.reg = 0x21 },
> > +	{ .mbps =  150,	.reg = 0x31 },
> > +	{ .mbps =  160,	.reg = 0x02 },
> > +	{ .mbps =  170,	.reg = 0x12 },
> > +	{ .mbps =  180,	.reg = 0x22 },
> > +	{ .mbps =  190,	.reg = 0x32 },
> > +	{ .mbps =  205,	.reg = 0x03 },
> > +	{ .mbps =  220,	.reg = 0x13 },
> > +	{ .mbps =  235,	.reg = 0x23 },
> > +	{ .mbps =  250,	.reg = 0x33 },
> > +	{ .mbps =  275,	.reg = 0x04 },
> > +	{ .mbps =  300,	.reg = 0x14 },
> > +	{ .mbps =  325,	.reg = 0x05 },
> > +	{ .mbps =  350,	.reg = 0x15 },
> > +	{ .mbps =  400,	.reg = 0x25 },
> > +	{ .mbps =  450,	.reg = 0x06 },
> > +	{ .mbps =  500,	.reg = 0x16 },
> > +	{ .mbps =  550,	.reg = 0x07 },
> > +	{ .mbps =  600,	.reg = 0x17 },
> > +	{ .mbps =  650,	.reg = 0x08 },
> > +	{ .mbps =  700,	.reg = 0x18 },
> > +	{ .mbps =  750,	.reg = 0x09 },
> > +	{ .mbps =  800,	.reg = 0x19 },
> > +	{ .mbps =  850,	.reg = 0x29 },
> > +	{ .mbps =  900,	.reg = 0x39 },
> > +	{ .mbps =  950,	.reg = 0x0A },
> > +	{ .mbps = 1000,	.reg = 0x1A },
> > +	{ .mbps = 1050,	.reg = 0x2A },
> > +	{ .mbps = 1100,	.reg = 0x3A },
> > +	{ .mbps = 1150,	.reg = 0x0B },
> > +	{ .mbps = 1200,	.reg = 0x1B },
> > +	{ .mbps = 1250,	.reg = 0x2B },
> > +	{ .mbps = 1300,	.reg = 0x3B },
> > +	{ .mbps = 1350,	.reg = 0x0C },
> > +	{ .mbps = 1400,	.reg = 0x1C },
> > +	{ .mbps = 1450,	.reg = 0x2C },
> > +	{ .mbps = 1500,	.reg = 0x3C },
> > +	/* guard */
> > +	{ .mbps =   0,	.reg = 0x00 },
> > +};
> > +
> > +/* PHY ESC Error Monitor */
> > +#define PHEERM_REG			0x74
> > +
> > +/* PHY Clock Lane Monitor */
> > +#define PHCLM_REG			0x78
> > +
> > +/* PHY Data Lane Monitor */
> > +#define PHDLM_REG			0x7c
> > +
> > +struct rcar_csi2_format {
> > +	unsigned int code;
> > +	unsigned int datatype;
> > +	unsigned int bpp;
> > +};
> > +
> > +static const struct rcar_csi2_format rcar_csi2_formats[] = {
> > +	{ .code = MEDIA_BUS_FMT_RGB888_1X24,	.datatype = 0x24, .bpp = 24},
> > +	{ .code = MEDIA_BUS_FMT_UYVY8_1X16,	.datatype = 0x1e, .bpp = 8 },
> > +	{ .code = MEDIA_BUS_FMT_UYVY8_2X8,	.datatype = 0x1e, .bpp = 8 },
> > +	{ .code = MEDIA_BUS_FMT_YUYV10_2X10,	.datatype = 0x1e, .bpp = 8 },
> > +};
> > +
> > +static const struct rcar_csi2_format *rcar_csi2_code_to_fmt(unsigned int code)
> > +{
> > +	int i;
> > +
> > +	for (i = 0; i < ARRAY_SIZE(rcar_csi2_formats); i++)
> > +		if (rcar_csi2_formats[i].code == code)
> > +			return rcar_csi2_formats + i;
> > +	return NULL;
> > +}
> > +
> > +enum rcar_csi2_pads {
> > +	RCAR_CSI2_SINK,
> > +	RCAR_CSI2_SOURCE_VC0,
> > +	RCAR_CSI2_SOURCE_VC1,
> > +	RCAR_CSI2_SOURCE_VC2,
> > +	RCAR_CSI2_SOURCE_VC3,
> > +	NR_OF_RCAR_CSI2_PAD,
> > +};
> > +
> > +struct rcar_csi2 {
> > +	struct device *dev;
> > +	void __iomem *base;
> > +
> > +	unsigned short lanes;
> > +	unsigned char lane_swap[4];
> > +
> > +	struct v4l2_subdev subdev;
> > +	struct media_pad pads[NR_OF_RCAR_CSI2_PAD];
> > +
> > +	struct v4l2_mbus_framefmt mf;
> > +
> > +	struct mutex lock;
> > +	int stream_count;
> > +
> > +	struct v4l2_async_notifier notifier;
> > +	struct {
> > +		struct v4l2_async_subdev asd;
> > +		struct v4l2_subdev *subdev;
> > +		struct fwnode_handle *fwnode;
> > +		unsigned int source_pad;
> > +	} remote;
> > +};
> > +
> > +static inline struct rcar_csi2 *sd_to_csi2(struct v4l2_subdev *sd)
> > +{
> > +	return container_of(sd, struct rcar_csi2, subdev);
> > +}
> > +
> > +static u32 rcar_csi2_read(struct rcar_csi2 *priv, unsigned int reg)
> > +{
> > +	return ioread32(priv->base + reg);
> > +}
> > +
> > +static void rcar_csi2_write(struct rcar_csi2 *priv, unsigned int reg, u32 data)
> > +{
> > +	iowrite32(data, priv->base + reg);
> > +}
> > +
> > +static void rcar_csi2_reset(struct rcar_csi2 *priv)
> > +{
> > +	rcar_csi2_write(priv, SRST_REG, SRST_SRST);
> > +	rcar_csi2_write(priv, SRST_REG, 0);
> > +}
> > +
> > +static int rcar_csi2_wait_phy_start(struct rcar_csi2 *priv)
> > +{
> > +	int timeout;
> > +
> > +	/* Wait for the clock and data lanes to enter LP-11 state. */
> > +	for (timeout = 100; timeout >= 0; timeout--) {
> > +		const u32 lane_mask = (1 << priv->lanes) - 1;
> > +
> > +		if ((rcar_csi2_read(priv, PHCLM_REG) & 1) == 1 &&
> > +		    (rcar_csi2_read(priv, PHDLM_REG) & lane_mask) == lane_mask)
> > +			return 0;
> > +
> > +		msleep(20);
> > +	}
> > +
> > +	dev_err(priv->dev, "Timeout waiting for LP-11 state\n");
> > +
> > +	return -ETIMEDOUT;
> > +}
> > +
> > +static int rcar_csi2_calc_phypll(struct rcar_csi2 *priv,
> > +				 struct v4l2_subdev *source,
> > +				 struct v4l2_mbus_framefmt *mf,
> > +				 u32 *phypll)
> > +{
> > +	const struct phypll_hsfreqrange *hsfreq;
> > +	const struct rcar_csi2_format *format;
> > +	struct v4l2_ext_controls ctrls;
> > +	struct v4l2_ext_control ctrl;
> > +	u64 mbps;
> > +	int ret;
> > +
> > +	memset(&ctrls, 0, sizeof(ctrls));
> > +	memset(&ctrl, 0, sizeof(ctrl));
> > +
> > +	ctrl.id = V4L2_CID_PIXEL_RATE;
> > +
> > +	ctrls.count = 1;
> > +	ctrls.controls = &ctrl;
> > +
> > +	ret = v4l2_g_ext_ctrls(source->ctrl_handler, &ctrls);
> 
> v4l2_ctrl_g_ctrl_int64(), please. Or do I miss something?

Thanks will fix.

> 
> > +	if (ret < 0) {
> > +		dev_err(priv->dev, "no link freq control in subdev %s\n",
> > +			source->name);
> > +		return ret;
> > +	}
> > +
> > +	format = rcar_csi2_code_to_fmt(mf->code);
> > +	if (!format) {
> > +		dev_err(priv->dev, "Unknown format: %d\n", mf->code);
> > +		return -EINVAL;
> > +	}
> > +
> > +	mbps = ctrl.value64 * format->bpp;
> > +	do_div(mbps, priv->lanes * 1000000);
> > +
> > +	for (hsfreq = phypll_hsfreqrange_map; hsfreq->mbps != 0; hsfreq++)
> > +		if (hsfreq->mbps >= mbps)
> > +			break;
> > +
> > +	if (!hsfreq->mbps) {
> > +		dev_err(priv->dev, "Unsupported PHY speed (%llu Mbps)", mbps);
> > +		return -ERANGE;
> > +	}
> > +
> > +	dev_dbg(priv->dev, "PHY HSFREQRANGE requested %llu got %u Mbps\n", mbps,
> > +		hsfreq->mbps);
> > +
> > +	*phypll = PHYPLL_HSFREQRANGE(hsfreq->reg);
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_start(struct rcar_csi2 *priv)
> > +{
> > +	const struct rcar_csi2_format *format;
> > +	struct v4l2_subdev_format fmt;
> > +	struct media_pad *source_pad;
> > +	struct v4l2_subdev *source = NULL;
> > +	struct v4l2_mbus_framefmt *mf = &fmt.format;
> > +	u32 phycnt, phypll, tmp;
> > +	u32 vcdt = 0, vcdt2 = 0;
> > +	unsigned int i;
> > +	int ret;
> > +
> > +	source_pad =
> > +		media_entity_remote_pad(&priv->subdev.entity.pads[RCAR_CSI2_SINK]);
> 
> Over 80 characters per line. I think you could split this up differently.

Will fix.

> 
> > +	if (!source_pad) {
> > +		dev_err(priv->dev, "Could not find remote source pad\n");
> > +		return -ENODEV;
> > +	}
> > +
> > +	source = media_entity_to_v4l2_subdev(source_pad->entity);
> > +	if (!source) {
> > +		dev_err(priv->dev, "Could not find remote subdevice\n");
> > +		return -ENODEV;
> > +	}
> > +
> > +	dev_dbg(priv->dev, "Using source %s pad: %u\n", source->name,
> > +		source_pad->index);
> > +
> > +	fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
> > +	fmt.pad = source_pad->index;
> > +	ret = v4l2_subdev_call(source, pad, get_fmt, NULL, &fmt);
> > +	if (ret)
> > +		return ret;
> > +
> > +	dev_dbg(priv->dev, "Input size (%dx%d%c)\n", mf->width,
> > +		mf->height, mf->field == V4L2_FIELD_NONE ? 'p' : 'i');
> > +
> > +	/*
> > +	 * Enable all Virtual Channels
> > +	 *
> > +	 * NOTE: I'ts not possible to get individual format for each
> 
> "It's"

Ops.. will fix :-)

> 
> > +	 *       source virtual channel. Once this is possible in V4L2
> > +	 *       it should be used here.
> > +	 */
> > +	for (i = 0; i < 4; i++) {
> > +
> > +		format = rcar_csi2_code_to_fmt(mf->code);
> > +		if (!format) {
> > +			dev_err(priv->dev, "Unsupported media bus format: %d\n",
> > +				mf->code);
> > +			return -EINVAL;
> > +		}
> > +
> > +		tmp = VCDT_SEL_VC(i) | VCDT_VCDTN_EN | VCDT_SEL_DTN_ON |
> > +			VCDT_SEL_DT(format->datatype);
> > +
> > +		/* Store in correct reg and offset */
> > +		if (i < 2)
> > +			vcdt |= tmp << ((i % 2) * 16);
> > +		else
> > +			vcdt2 |= tmp << ((i % 2) * 16);
> > +	}
> > +
> > +	switch (priv->lanes) {
> > +	case 1:
> > +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_0;
> > +		break;
> > +	case 2:
> > +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_1 | PHYCNT_ENABLE_0;
> > +		break;
> > +	case 4:
> > +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_3 | PHYCNT_ENABLE_2 |
> > +			PHYCNT_ENABLE_1 | PHYCNT_ENABLE_0;
> > +		break;
> > +	default:
> > +		return -EINVAL;
> > +	}
> > +
> > +	ret = rcar_csi2_calc_phypll(priv, source, mf, &phypll);
> > +	if (ret)
> > +		return ret;
> > +
> > +	/* Init */
> > +	rcar_csi2_write(priv, TREF_REG, TREF_TREF);
> > +	rcar_csi2_reset(priv);
> > +	rcar_csi2_write(priv, PHTC_REG, 0);
> > +
> > +	/* Configure */
> > +	rcar_csi2_write(priv, FLD_REG, FLD_FLD_NUM(2) | FLD_FLD_EN4 |
> > +			FLD_FLD_EN3 | FLD_FLD_EN2 | FLD_FLD_EN);
> > +	rcar_csi2_write(priv, VCDT_REG, vcdt);
> > +	rcar_csi2_write(priv, VCDT2_REG, vcdt2);
> > +	/* Lanes are zero indexed */
> > +	rcar_csi2_write(priv, LSWAP_REG,
> > +			LSWAP_L0SEL(priv->lane_swap[0] - 1) |
> > +			LSWAP_L1SEL(priv->lane_swap[1] - 1) |
> > +			LSWAP_L2SEL(priv->lane_swap[2] - 1) |
> > +			LSWAP_L3SEL(priv->lane_swap[3] - 1));
> 
> How are the lanes numbered?

In the datasheet they are numbered CSIn_DATA{0,1,2,3}.

> 
> Do you have a fixed number of lanes per receiver?

Two different configurations exists a 4-lane CSI-2 receiver and a 2-lane 
CSI-2 receiver.

> 
> > +
> > +	/* Start */
> > +	rcar_csi2_write(priv, PHYPLL_REG, phypll);
> > +	rcar_csi2_write(priv, PHYCNT_REG, phycnt);
> > +	rcar_csi2_write(priv, LINKCNT_REG, LINKCNT_MONITOR_EN |
> > +			LINKCNT_REG_MONI_PACT_EN | LINKCNT_ICLK_NONSTOP);
> > +	rcar_csi2_write(priv, PHYCNT_REG, phycnt | PHYCNT_SHUTDOWNZ);
> > +	rcar_csi2_write(priv, PHYCNT_REG, phycnt | PHYCNT_SHUTDOWNZ |
> > +			PHYCNT_RSTZ);
> > +
> > +	return rcar_csi2_wait_phy_start(priv);
> > +}
> > +
> > +static void rcar_csi2_stop(struct rcar_csi2 *priv)
> > +{
> > +	rcar_csi2_write(priv, PHYCNT_REG, 0);
> > +
> > +	rcar_csi2_reset(priv);
> > +}
> > +
> > +static int rcar_csi2_sd_info(struct rcar_csi2 *priv, struct v4l2_subdev **sd)
> > +{
> > +	struct media_pad *pad;
> > +
> > +	pad = media_entity_remote_pad(&priv->pads[RCAR_CSI2_SINK]);
> > +	if (!pad) {
> > +		dev_err(priv->dev, "Could not find remote pad\n");
> > +		return -ENODEV;
> > +	}
> > +
> > +	*sd = media_entity_to_v4l2_subdev(pad->entity);
> > +	if (!*sd) {
> > +		dev_err(priv->dev, "Could not find remote subdevice\n");
> > +		return -ENODEV;
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_s_stream(struct v4l2_subdev *sd, int enable)
> > +{
> > +	struct rcar_csi2 *priv = sd_to_csi2(sd);
> > +	struct v4l2_subdev *nextsd;
> > +	int ret;
> > +
> > +	mutex_lock(&priv->lock);
> > +
> > +	ret = rcar_csi2_sd_info(priv, &nextsd);
> > +	if (ret)
> > +		goto out;
> > +
> > +	priv->stream_count += enable ? 1 : -1;
> > +
> > +	if (enable && priv->stream_count == 1) {
> > +		ret =  rcar_csi2_start(priv);
> > +		if (ret)
> > +			goto out;
> > +		ret = v4l2_subdev_call(nextsd, video, s_stream, 1);
> > +
> > +	} else if (!enable && !priv->stream_count) {
> > +		rcar_csi2_stop(priv);
> > +		ret = v4l2_subdev_call(nextsd, video, s_stream, 0);
> > +	}
> > +out:
> > +	mutex_unlock(&priv->lock);
> > +
> > +	return ret;
> > +}
> > +
> > +static int rcar_csi2_s_power(struct v4l2_subdev *sd, int on)
> > +{
> > +	struct rcar_csi2 *priv = sd_to_csi2(sd);
> > +
> > +	if (on)
> > +		pm_runtime_get_sync(priv->dev);
> > +	else
> > +		pm_runtime_put(priv->dev);
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_set_pad_format(struct v4l2_subdev *sd,
> > +				    struct v4l2_subdev_pad_config *cfg,
> > +				    struct v4l2_subdev_format *format)
> > +{
> > +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> > +
> > +	if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE)
> > +		priv->mf = format->format;
> 
> How about the try formats? E.g.
> 
> *v4l2_subdev_get_try_format() = format->fmt;

Thanks will fix.

> 
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_get_pad_format(struct v4l2_subdev *sd,
> > +				    struct v4l2_subdev_pad_config *cfg,
> > +				    struct v4l2_subdev_format *format)
> > +{
> > +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> > +
> > +	format->format = priv->mf;
> 
> Ditto.

Ditto :-)

> 
> > +
> > +	return 0;
> > +}
> > +
> > +static const struct v4l2_subdev_video_ops rcar_csi2_video_ops = {
> > +	.s_stream = rcar_csi2_s_stream,
> > +};
> > +
> > +static const struct v4l2_subdev_core_ops rcar_csi2_subdev_core_ops = {
> > +	.s_power = rcar_csi2_s_power,
> > +};
> > +
> > +static const struct v4l2_subdev_pad_ops rcar_csi2_pad_ops = {
> > +	.set_fmt = rcar_csi2_set_pad_format,
> > +	.get_fmt = rcar_csi2_get_pad_format,
> > +};
> > +
> > +static const struct v4l2_subdev_ops rcar_csi2_subdev_ops = {
> > +	.video	= &rcar_csi2_video_ops,
> > +	.core	= &rcar_csi2_subdev_core_ops,
> > +	.pad	= &rcar_csi2_pad_ops,
> > +};
> > +
> > +/* -----------------------------------------------------------------------------
> > + * Async and registered of subdevices and links
> > + */
> > +
> > +#define notifier_to_priv(n) container_of(n, struct rcar_csi2, notifier)
> > +
> > +static int rcar_csi2_notify_complete(struct v4l2_async_notifier *notifier)
> > +{
> > +	struct rcar_csi2 *priv = notifier_to_priv(notifier);
> > +	int ret;
> > +
> > +	ret = v4l2_device_register_subdev_nodes(priv->subdev.v4l2_dev);
> > +	if (ret) {
> > +		dev_err(priv->dev, "Failed to register subdev nodes\n");
> > +		return ret;
> > +	}
> > +
> > +	return media_create_pad_link(&priv->remote.subdev->entity,
> > +				     priv->remote.source_pad,
> > +				     &priv->subdev.entity, 0,
> > +				     MEDIA_LNK_FL_ENABLED |
> > +				     MEDIA_LNK_FL_IMMUTABLE);
> > +}
> > +
> > +static int rcar_csi2_notify_bound(struct v4l2_async_notifier *notifier,
> > +				   struct v4l2_subdev *subdev,
> > +				   struct v4l2_async_subdev *asd)
> > +{
> > +	struct rcar_csi2 *priv = notifier_to_priv(notifier);
> > +	int ret;
> > +
> > +	v4l2_set_subdev_hostdata(subdev, priv);
> > +
> > +	ret = media_entity_pad_from_fwnode(&subdev->entity,
> > +					   priv->remote.fwnode,
> > +					   MEDIA_PAD_FL_SOURCE,
> > +					   &priv->remote.source_pad);
> > +	if (ret) {
> > +		dev_err(priv->dev, "Failed to find pad for %s\n",
> > +			subdev->name);
> > +		return ret;
> > +	}
> > +
> > +	dev_dbg(priv->dev, "Bound %s pad: %d\n", subdev->name,
> > +		priv->remote.source_pad);
> > +	priv->remote.subdev = subdev;
> > +
> > +	return 0;
> > +}
> 
> A newline would be nice here.

Yes.

> 
> > +static void rcar_csi2_notify_unbind(struct v4l2_async_notifier *notifier,
> > +				     struct v4l2_subdev *subdev,
> > +				     struct v4l2_async_subdev *asd)
> > +{
> > +	struct rcar_csi2 *priv = notifier_to_priv(notifier);
> > +
> > +	dev_dbg(priv->dev, "Unbind %s\n", subdev->name);
> > +	priv->remote.subdev = NULL;
> > +}
> > +
> > +static int rcar_csi2_registered(struct v4l2_subdev *sd)
> > +{
> > +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> > +	struct v4l2_async_subdev **subdevs = NULL;
> > +	int ret;
> > +
> > +	subdevs = devm_kzalloc(priv->dev, sizeof(*subdevs), GFP_KERNEL);
> > +	if (subdevs == NULL)
> > +		return -ENOMEM;
> > +
> > +	subdevs[0] = &priv->remote.asd;
> > +
> > +	priv->notifier.num_subdevs = 1;
> > +	priv->notifier.subdevs = subdevs;
> > +	priv->notifier.bound = rcar_csi2_notify_bound;
> > +	priv->notifier.unbind = rcar_csi2_notify_unbind;
> > +	priv->notifier.complete = rcar_csi2_notify_complete;
> > +
> > +	ret = v4l2_async_subnotifier_register(&priv->subdev, &priv->notifier);
> > +	if (ret < 0) {
> > +		dev_err(priv->dev, "Notifier registration failed\n");
> > +		return ret;
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static void rcar_csi2_unregistered(struct v4l2_subdev *sd)
> > +{
> > +	struct rcar_csi2 *priv = container_of(sd, struct rcar_csi2, subdev);
> > +
> > +	v4l2_async_subnotifier_unregister(&priv->notifier);
> > +}
> > +
> > +static const struct v4l2_subdev_internal_ops rcar_csi2_internal_ops = {
> > +	.registered = rcar_csi2_registered,
> > +	.unregistered = rcar_csi2_unregistered,
> > +};
> > +
> > +static int rcar_csi2_parse_dt_subdevice(struct rcar_csi2 *priv)
> > +{
> > +	struct device_node *remote, *ep;
> > +	struct v4l2_fwnode_endpoint v4l2_ep;
> > +	int ret;
> > +
> > +	ep = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0);
> > +	if (!ep) {
> > +		dev_err(priv->dev, "Not connected to subdevice\n");
> > +		return -EINVAL;
> > +	}
> > +
> > +	ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &v4l2_ep);
> > +	if (ret) {
> > +		dev_err(priv->dev, "Could not parse v4l2 endpoint\n");
> > +		of_node_put(ep);
> > +		return -EINVAL;
> > +	}
> > +
> > +	if (v4l2_ep.bus_type != V4L2_MBUS_CSI2) {
> > +		dev_err(priv->dev, "Unknown media bus type: 0x%x\n",
> > +			v4l2_ep.bus_type);
> > +		of_node_put(ep);
> > +		return -EINVAL;
> > +	}
> > +
> > +	priv->remote.fwnode =
> > +		fwnode_graph_get_remote_endpoint(of_fwnode_handle(ep));
> > +
> > +	remote = of_graph_get_remote_port_parent(ep);
> > +	of_node_put(ep);
> > +	if (!remote) {
> > +		dev_err(priv->dev, "No subdevice found for endpoint '%s'\n",
> > +			of_node_full_name(ep));
> > +		return -EINVAL;
> > +	}
> > +
> > +	priv->remote.asd.match.fwnode.fwnode = of_fwnode_handle(remote);
> > +	priv->remote.asd.match_type = V4L2_ASYNC_MATCH_FWNODE;
> > +
> > +	dev_dbg(priv->dev, "Found '%s'\n", of_node_full_name(remote));
> > +
> > +	return 0;
> > +}
> > +
> > +/* -----------------------------------------------------------------------------
> > + * Platform Device Driver
> > + */
> > +
> > +static const struct of_device_id rcar_csi2_of_table[] = {
> > +	{ .compatible = "renesas,rcar-gen3-csi2" },
> > +	{ },
> > +};
> > +MODULE_DEVICE_TABLE(of, rcar_csi2_of_table);
> > +
> > +static const struct media_entity_operations rcar_csi2_entity_ops = {
> > +	.link_validate = v4l2_subdev_link_validate,
> > +};
> > +
> > +static int rcar_csi2_parse_dt_settings(struct rcar_csi2 *priv)
> > +{
> > +	struct v4l2_fwnode_endpoint v4l2_ep;
> > +	struct device_node *ep;
> > +	unsigned int i;
> > +	int ret;
> > +
> > +	ep = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0);
> > +	if (!ep)
> > +		return -EINVAL;
> > +
> > +	ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &v4l2_ep);
> > +	of_node_put(ep);
> > +	if (ret) {
> > +		dev_err(priv->dev, "Could not parse v4l2 endpoint\n");
> > +		return -EINVAL;
> > +	}
> > +
> > +	if (v4l2_ep.bus_type != V4L2_MBUS_CSI2) {
> > +		dev_err(priv->dev, "Unsupported media bus type for %s\n",
> > +			of_node_full_name(ep));
> > +		return -EINVAL;
> > +	}
> > +
> > +	priv->lanes = v4l2_ep.bus.mipi_csi2.num_data_lanes;
> > +	if (priv->lanes != 1 && priv->lanes != 2 && priv->lanes != 4) {
> > +		dev_err(priv->dev, "Unsupported number of data-lanes: %d\n",
> > +			priv->lanes);
> > +		return -EINVAL;
> > +	}
> > +
> > +	for (i = 0; i < ARRAY_SIZE(priv->lane_swap); i++) {
> > +		priv->lane_swap[i] = i < priv->lanes ?
> > +			v4l2_ep.bus.mipi_csi2.data_lanes[i] : i;
> > +
> > +		/* Check for valid lane number */
> > +		if (priv->lane_swap[i] < 1 || priv->lane_swap[i] > 4) {
> 
> Do you also support for three lanes? Based on the code elsewhere, it doesn't
> seem like that.

Yes 3-lanes should be supported but I have no way of testing this. But I 
do belive the code is prepared to handle it, see for example in the 
driver all logic around priv->lanes variable, am I missing something?

> 
> > +			dev_err(priv->dev, "data-lanes must be in 1-4 range\n");
> > +			return -EINVAL;
> > +		}
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_probe_resources(struct rcar_csi2 *priv,
> > +				     struct platform_device *pdev)
> > +{
> > +	struct resource *mem;
> > +	int irq;
> > +
> > +	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > +	if (!mem)
> > +		return -ENODEV;
> > +
> > +	priv->base = devm_ioremap_resource(&pdev->dev, mem);
> > +	if (IS_ERR(priv->base))
> > +		return PTR_ERR(priv->base);
> > +
> > +	irq = platform_get_irq(pdev, 0);
> > +	if (irq < 0)
> > +		return irq;
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_probe(struct platform_device *pdev)
> > +{
> > +	struct rcar_csi2 *priv;
> > +	unsigned int i;
> > +	int ret;
> > +
> > +	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
> > +	if (!priv)
> > +		return -ENOMEM;
> > +
> > +	priv->dev = &pdev->dev;
> > +
> > +	mutex_init(&priv->lock);
> > +	priv->stream_count = 0;
> > +
> > +	ret = rcar_csi2_parse_dt_settings(priv);
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = rcar_csi2_parse_dt_subdevice(priv);
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = rcar_csi2_probe_resources(priv, pdev);
> > +	if (ret) {
> > +		dev_err(priv->dev, "Failed to get resources\n");
> > +		return ret;
> > +	}
> > +
> > +	platform_set_drvdata(pdev, priv);
> > +
> > +	priv->subdev.owner = THIS_MODULE;
> > +	priv->subdev.dev = &pdev->dev;
> > +	v4l2_subdev_init(&priv->subdev, &rcar_csi2_subdev_ops);
> > +	v4l2_set_subdevdata(&priv->subdev, &pdev->dev);
> > +	snprintf(priv->subdev.name, V4L2_SUBDEV_NAME_SIZE, "%s %s",
> > +		 KBUILD_MODNAME, dev_name(&pdev->dev));
> > +	priv->subdev.flags = V4L2_SUBDEV_FL_HAS_DEVNODE;
> > +	priv->subdev.internal_ops = &rcar_csi2_internal_ops;
> > +
> > +	priv->subdev.entity.function = MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER;
> > +	priv->subdev.entity.ops = &rcar_csi2_entity_ops;
> > +
> > +	priv->pads[RCAR_CSI2_SINK].flags = MEDIA_PAD_FL_SINK;
> > +	for (i = RCAR_CSI2_SOURCE_VC0; i < NR_OF_RCAR_CSI2_PAD; i++)
> > +		priv->pads[i].flags = MEDIA_PAD_FL_SOURCE;
> > +
> > +	ret = media_entity_pads_init(&priv->subdev.entity, NR_OF_RCAR_CSI2_PAD,
> > +				     priv->pads);
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = v4l2_async_register_subdev(&priv->subdev);
> > +	if (ret < 0)
> > +		return ret;
> > +
> > +	pm_runtime_enable(&pdev->dev);
> > +
> > +	dev_info(priv->dev, "%d lanes found\n", priv->lanes);
> > +
> > +	return 0;
> > +}
> > +
> > +static int rcar_csi2_remove(struct platform_device *pdev)
> > +{
> > +	struct rcar_csi2 *priv = platform_get_drvdata(pdev);
> > +
> > +	v4l2_async_unregister_subdev(&priv->subdev);
> > +
> > +	pm_runtime_disable(&pdev->dev);
> > +
> > +	return 0;
> > +}
> > +
> > +static struct platform_driver __refdata rcar_csi2_pdrv = {
> > +	.remove	= rcar_csi2_remove,
> > +	.probe	= rcar_csi2_probe,
> > +	.driver	= {
> > +		.name	= "rcar-csi2",
> > +		.of_match_table	= of_match_ptr(rcar_csi2_of_table),
> > +	},
> > +};
> > +
> > +module_platform_driver(rcar_csi2_pdrv);
> > +
> > +MODULE_AUTHOR("Niklas S�derlund <niklas.soderlund@ragnatech.se>");
> > +MODULE_DESCRIPTION("Renesas R-Car MIPI CSI-2 receiver");
> > +MODULE_LICENSE("GPL v2");
> 
> -- 
> Regards,
> 
> Sakari Ailus
> e-mail: sakari.ailus@iki.fi	XMPP: sailus@retiisi.org.uk

-- 
Regards,
Niklas S�derlund

Re: [PATCH v7 2/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver driver

[Sakari Ailus]

Hejssan Niklas,

On Thu, Jun 15, 2017 at 10:48:20AM +0200, Niklas Söderlund wrote:
> Hi Sakari,
> 
> Thanks for your comments.
> 
> On 2017-05-29 14:35:16 +0300, Sakari Ailus wrote:
> > Hi Niklas,
> > 
> > A few comments below.
> > 
> > On Wed, May 24, 2017 at 02:13:53AM +0200, Niklas Söderlund wrote:
> > > From: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> > > 
> > > A V4L2 driver for Renesas R-Car MIPI CSI-2 receiver. The driver
> > > supports the rcar-vin driver on R-Car Gen3 SoCs where separate CSI-2
> > > hardware blocks are connected between the video sources and the video
> > > grabbers (VIN).
> > > 
> > > Driver is based on a prototype by Koji Matsuoka in the Renesas BSP.
> > > 
> > > Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> > > ---
> > >  drivers/media/platform/rcar-vin/Kconfig     |  12 +
> > >  drivers/media/platform/rcar-vin/Makefile    |   1 +
> > >  drivers/media/platform/rcar-vin/rcar-csi2.c | 867 ++++++++++++++++++++++++++++
> > >  3 files changed, 880 insertions(+)
> > >  create mode 100644 drivers/media/platform/rcar-vin/rcar-csi2.c
> > > 
> > > diff --git a/drivers/media/platform/rcar-vin/Kconfig b/drivers/media/platform/rcar-vin/Kconfig
> > > index af4c98b44d2e22cb..6875f30c1ae42631 100644
> > > --- a/drivers/media/platform/rcar-vin/Kconfig
> > > +++ b/drivers/media/platform/rcar-vin/Kconfig
> > > @@ -1,3 +1,15 @@
> > > +config VIDEO_RCAR_CSI2
> > > +	tristate "R-Car MIPI CSI-2 Receiver"
> > > +	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && OF
> > > +	depends on ARCH_RENESAS || COMPILE_TEST
> > > +	select V4L2_FWNODE
> > > +	---help---
> > > +	  Support for Renesas R-Car MIPI CSI-2 receiver.
> > > +	  Supports R-Car Gen3 SoCs.
> > > +
> > > +	  To compile this driver as a module, choose M here: the
> > > +	  module will be called rcar-csi2.
> > > +
> > >  config VIDEO_RCAR_VIN
> > >  	tristate "R-Car Video Input (VIN) Driver"
> > >  	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && OF && HAS_DMA && MEDIA_CONTROLLER
> > > diff --git a/drivers/media/platform/rcar-vin/Makefile b/drivers/media/platform/rcar-vin/Makefile
> > > index 48c5632c21dc060b..5ab803d3e7c1aa57 100644
> > > --- a/drivers/media/platform/rcar-vin/Makefile
> > > +++ b/drivers/media/platform/rcar-vin/Makefile
> > > @@ -1,3 +1,4 @@
> > >  rcar-vin-objs = rcar-core.o rcar-dma.o rcar-v4l2.o
> > >  
> > > +obj-$(CONFIG_VIDEO_RCAR_CSI2) += rcar-csi2.o
> > >  obj-$(CONFIG_VIDEO_RCAR_VIN) += rcar-vin.o
> > > diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
> > > new file mode 100644
> > > index 0000000000000000..1175f1fe4b139a13
> > > --- /dev/null
> > > +++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
> > > @@ -0,0 +1,867 @@
> > > +/*
> > > + * Driver for Renesas R-Car MIPI CSI-2 Receiver
> > > + *
> > > + * Copyright (C) 2017 Renesas Electronics Corp.
> > > + *
> > > + * This program is free software; you can redistribute  it and/or modify it
> > > + * under  the terms of  the GNU General  Public License as published by the
> > > + * Free Software Foundation;  either version 2 of the  License, or (at your
> > > + * option) any later version.
> > > + */
> > > +
> > > +#include <linux/delay.h>
> > > +#include <linux/interrupt.h>
> > > +#include <linux/io.h>
> > > +#include <linux/module.h>
> > > +#include <linux/of.h>
> > > +#include <linux/of_device.h>
> > > +#include <linux/of_graph.h>
> > > +#include <linux/platform_device.h>
> > > +#include <linux/pm_runtime.h>
> > > +
> > > +#include <media/v4l2-ctrls.h>
> > > +#include <media/v4l2-device.h>
> > > +#include <media/v4l2-fwnode.h>
> > > +#include <media/v4l2-mc.h>
> > > +#include <media/v4l2-subdev.h>
> > > +
> > > +/* Register offsets and bits */
> > > +
> > > +/* Control Timing Select */
> > > +#define TREF_REG			0x00
> > > +#define TREF_TREF			(1 << 0)
> > > +
> > > +/* Software Reset */
> > > +#define SRST_REG			0x04
> > > +#define SRST_SRST			(1 << 0)
> > > +
> > > +/* PHY Operation Control */
> > > +#define PHYCNT_REG			0x08
> > > +#define PHYCNT_SHUTDOWNZ		(1 << 17)
> > > +#define PHYCNT_RSTZ			(1 << 16)
> > > +#define PHYCNT_ENABLECLK		(1 << 4)
> > > +#define PHYCNT_ENABLE_3			(1 << 3)
> > > +#define PHYCNT_ENABLE_2			(1 << 2)
> > > +#define PHYCNT_ENABLE_1			(1 << 1)
> > > +#define PHYCNT_ENABLE_0			(1 << 0)
> > > +
> > > +/* Checksum Control */
> > > +#define CHKSUM_REG			0x0c
> > > +#define CHKSUM_ECC_EN			(1 << 1)
> > > +#define CHKSUM_CRC_EN			(1 << 0)
> > > +
> > > +/*
> > > + * Channel Data Type Select
> > > + * VCDT[0-15]:  Channel 1 VCDT[16-31]:  Channel 2
> > > + * VCDT2[0-15]: Channel 3 VCDT2[16-31]: Channel 4
> > > + */
> > > +#define VCDT_REG			0x10
> > > +#define VCDT2_REG			0x14
> > > +#define VCDT_VCDTN_EN			(1 << 15)
> > > +#define VCDT_SEL_VC(n)			(((n) & 0x3) << 8)
> > > +#define VCDT_SEL_DTN_ON			(1 << 6)
> > > +#define VCDT_SEL_DT(n)			(((n) & 0x3f) << 0)
> > > +
> > > +/* Frame Data Type Select */
> > > +#define FRDT_REG			0x18
> > > +
> > > +/* Field Detection Control */
> > > +#define FLD_REG				0x1c
> > > +#define FLD_FLD_NUM(n)			(((n) & 0xff) << 16)
> > > +#define FLD_FLD_EN4			(1 << 3)
> > > +#define FLD_FLD_EN3			(1 << 2)
> > > +#define FLD_FLD_EN2			(1 << 1)
> > > +#define FLD_FLD_EN			(1 << 0)
> > > +
> > > +/* Automatic Standby Control */
> > > +#define ASTBY_REG			0x20
> > > +
> > > +/* Long Data Type Setting 0 */
> > > +#define LNGDT0_REG			0x28
> > > +
> > > +/* Long Data Type Setting 1 */
> > > +#define LNGDT1_REG			0x2c
> > > +
> > > +/* Interrupt Enable */
> > > +#define INTEN_REG			0x30
> > > +
> > > +/* Interrupt Source Mask */
> > > +#define INTCLOSE_REG			0x34
> > > +
> > > +/* Interrupt Status Monitor */
> > > +#define INTSTATE_REG			0x38
> > > +
> > > +/* Interrupt Error Status Monitor */
> > > +#define INTERRSTATE_REG			0x3c
> > > +
> > > +/* Short Packet Data */
> > > +#define SHPDAT_REG			0x40
> > > +
> > > +/* Short Packet Count */
> > > +#define SHPCNT_REG			0x44
> > > +
> > > +/* LINK Operation Control */
> > > +#define LINKCNT_REG			0x48
> > > +#define LINKCNT_MONITOR_EN		(1 << 31)
> > > +#define LINKCNT_REG_MONI_PACT_EN	(1 << 25)
> > > +#define LINKCNT_ICLK_NONSTOP		(1 << 24)
> > > +
> > > +/* Lane Swap */
> > > +#define LSWAP_REG			0x4c
> > > +#define LSWAP_L3SEL(n)			(((n) & 0x3) << 6)
> > > +#define LSWAP_L2SEL(n)			(((n) & 0x3) << 4)
> > > +#define LSWAP_L1SEL(n)			(((n) & 0x3) << 2)
> > > +#define LSWAP_L0SEL(n)			(((n) & 0x3) << 0)
> > > +
> > > +/* PHY Test Interface Clear */
> > > +#define PHTC_REG			0x58
> > > +#define PHTC_TESTCLR			(1 << 0)
> > > +
> > > +/* PHY Frequency Control */
> > > +#define PHYPLL_REG			0x68
> > > +#define PHYPLL_HSFREQRANGE(n)		((n) << 16)
> > > +
> > > +struct phypll_hsfreqrange {
> > > +	unsigned int	mbps;
> > > +	unsigned char	reg;
> > > +};
> > > +
> > > +static const struct phypll_hsfreqrange phypll_hsfreqrange_map[] = {
> > > +	{ .mbps =   80,	.reg = 0x00 },
> > > +	{ .mbps =   90,	.reg = 0x10 },
> > > +	{ .mbps =  100,	.reg = 0x20 },
> > > +	{ .mbps =  110,	.reg = 0x30 },
> > > +	{ .mbps =  120,	.reg = 0x01 },
> > > +	{ .mbps =  130,	.reg = 0x11 },
> > > +	{ .mbps =  140,	.reg = 0x21 },
> > > +	{ .mbps =  150,	.reg = 0x31 },
> > > +	{ .mbps =  160,	.reg = 0x02 },
> > > +	{ .mbps =  170,	.reg = 0x12 },
> > > +	{ .mbps =  180,	.reg = 0x22 },
> > > +	{ .mbps =  190,	.reg = 0x32 },
> > > +	{ .mbps =  205,	.reg = 0x03 },
> > > +	{ .mbps =  220,	.reg = 0x13 },
> > > +	{ .mbps =  235,	.reg = 0x23 },
> > > +	{ .mbps =  250,	.reg = 0x33 },
> > > +	{ .mbps =  275,	.reg = 0x04 },
> > > +	{ .mbps =  300,	.reg = 0x14 },
> > > +	{ .mbps =  325,	.reg = 0x05 },
> > > +	{ .mbps =  350,	.reg = 0x15 },
> > > +	{ .mbps =  400,	.reg = 0x25 },
> > > +	{ .mbps =  450,	.reg = 0x06 },
> > > +	{ .mbps =  500,	.reg = 0x16 },
> > > +	{ .mbps =  550,	.reg = 0x07 },
> > > +	{ .mbps =  600,	.reg = 0x17 },
> > > +	{ .mbps =  650,	.reg = 0x08 },
> > > +	{ .mbps =  700,	.reg = 0x18 },
> > > +	{ .mbps =  750,	.reg = 0x09 },
> > > +	{ .mbps =  800,	.reg = 0x19 },
> > > +	{ .mbps =  850,	.reg = 0x29 },
> > > +	{ .mbps =  900,	.reg = 0x39 },
> > > +	{ .mbps =  950,	.reg = 0x0A },
> > > +	{ .mbps = 1000,	.reg = 0x1A },
> > > +	{ .mbps = 1050,	.reg = 0x2A },
> > > +	{ .mbps = 1100,	.reg = 0x3A },
> > > +	{ .mbps = 1150,	.reg = 0x0B },
> > > +	{ .mbps = 1200,	.reg = 0x1B },
> > > +	{ .mbps = 1250,	.reg = 0x2B },
> > > +	{ .mbps = 1300,	.reg = 0x3B },
> > > +	{ .mbps = 1350,	.reg = 0x0C },
> > > +	{ .mbps = 1400,	.reg = 0x1C },
> > > +	{ .mbps = 1450,	.reg = 0x2C },
> > > +	{ .mbps = 1500,	.reg = 0x3C },
> > > +	/* guard */
> > > +	{ .mbps =   0,	.reg = 0x00 },
> > > +};
> > > +
> > > +/* PHY ESC Error Monitor */
> > > +#define PHEERM_REG			0x74
> > > +
> > > +/* PHY Clock Lane Monitor */
> > > +#define PHCLM_REG			0x78
> > > +
> > > +/* PHY Data Lane Monitor */
> > > +#define PHDLM_REG			0x7c
> > > +
> > > +struct rcar_csi2_format {
> > > +	unsigned int code;
> > > +	unsigned int datatype;
> > > +	unsigned int bpp;
> > > +};
> > > +
> > > +static const struct rcar_csi2_format rcar_csi2_formats[] = {
> > > +	{ .code = MEDIA_BUS_FMT_RGB888_1X24,	.datatype = 0x24, .bpp = 24},
> > > +	{ .code = MEDIA_BUS_FMT_UYVY8_1X16,	.datatype = 0x1e, .bpp = 8 },
> > > +	{ .code = MEDIA_BUS_FMT_UYVY8_2X8,	.datatype = 0x1e, .bpp = 8 },
> > > +	{ .code = MEDIA_BUS_FMT_YUYV10_2X10,	.datatype = 0x1e, .bpp = 8 },
> > > +};
> > > +
> > > +static const struct rcar_csi2_format *rcar_csi2_code_to_fmt(unsigned int code)
> > > +{
> > > +	int i;
> > > +
> > > +	for (i = 0; i < ARRAY_SIZE(rcar_csi2_formats); i++)
> > > +		if (rcar_csi2_formats[i].code == code)
> > > +			return rcar_csi2_formats + i;
> > > +	return NULL;
> > > +}
> > > +
> > > +enum rcar_csi2_pads {
> > > +	RCAR_CSI2_SINK,
> > > +	RCAR_CSI2_SOURCE_VC0,
> > > +	RCAR_CSI2_SOURCE_VC1,
> > > +	RCAR_CSI2_SOURCE_VC2,
> > > +	RCAR_CSI2_SOURCE_VC3,
> > > +	NR_OF_RCAR_CSI2_PAD,
> > > +};
> > > +
> > > +struct rcar_csi2 {
> > > +	struct device *dev;
> > > +	void __iomem *base;
> > > +
> > > +	unsigned short lanes;
> > > +	unsigned char lane_swap[4];
> > > +
> > > +	struct v4l2_subdev subdev;
> > > +	struct media_pad pads[NR_OF_RCAR_CSI2_PAD];
> > > +
> > > +	struct v4l2_mbus_framefmt mf;
> > > +
> > > +	struct mutex lock;
> > > +	int stream_count;
> > > +
> > > +	struct v4l2_async_notifier notifier;
> > > +	struct {
> > > +		struct v4l2_async_subdev asd;
> > > +		struct v4l2_subdev *subdev;
> > > +		struct fwnode_handle *fwnode;
> > > +		unsigned int source_pad;
> > > +	} remote;
> > > +};
> > > +
> > > +static inline struct rcar_csi2 *sd_to_csi2(struct v4l2_subdev *sd)
> > > +{
> > > +	return container_of(sd, struct rcar_csi2, subdev);
> > > +}
> > > +
> > > +static u32 rcar_csi2_read(struct rcar_csi2 *priv, unsigned int reg)
> > > +{
> > > +	return ioread32(priv->base + reg);
> > > +}
> > > +
> > > +static void rcar_csi2_write(struct rcar_csi2 *priv, unsigned int reg, u32 data)
> > > +{
> > > +	iowrite32(data, priv->base + reg);
> > > +}
> > > +
> > > +static void rcar_csi2_reset(struct rcar_csi2 *priv)
> > > +{
> > > +	rcar_csi2_write(priv, SRST_REG, SRST_SRST);
> > > +	rcar_csi2_write(priv, SRST_REG, 0);
> > > +}
> > > +
> > > +static int rcar_csi2_wait_phy_start(struct rcar_csi2 *priv)
> > > +{
> > > +	int timeout;
> > > +
> > > +	/* Wait for the clock and data lanes to enter LP-11 state. */
> > > +	for (timeout = 100; timeout >= 0; timeout--) {
> > > +		const u32 lane_mask = (1 << priv->lanes) - 1;
> > > +
> > > +		if ((rcar_csi2_read(priv, PHCLM_REG) & 1) == 1 &&
> > > +		    (rcar_csi2_read(priv, PHDLM_REG) & lane_mask) == lane_mask)
> > > +			return 0;
> > > +
> > > +		msleep(20);
> > > +	}
> > > +
> > > +	dev_err(priv->dev, "Timeout waiting for LP-11 state\n");
> > > +
> > > +	return -ETIMEDOUT;
> > > +}
> > > +
> > > +static int rcar_csi2_calc_phypll(struct rcar_csi2 *priv,
> > > +				 struct v4l2_subdev *source,
> > > +				 struct v4l2_mbus_framefmt *mf,
> > > +				 u32 *phypll)
> > > +{
> > > +	const struct phypll_hsfreqrange *hsfreq;
> > > +	const struct rcar_csi2_format *format;
> > > +	struct v4l2_ext_controls ctrls;
> > > +	struct v4l2_ext_control ctrl;
> > > +	u64 mbps;
> > > +	int ret;
> > > +
> > > +	memset(&ctrls, 0, sizeof(ctrls));
> > > +	memset(&ctrl, 0, sizeof(ctrl));
> > > +
> > > +	ctrl.id = V4L2_CID_PIXEL_RATE;
> > > +
> > > +	ctrls.count = 1;
> > > +	ctrls.controls = &ctrl;
> > > +
> > > +	ret = v4l2_g_ext_ctrls(source->ctrl_handler, &ctrls);
> > 
> > v4l2_ctrl_g_ctrl_int64(), please. Or do I miss something?
> 
> Thanks will fix.
> 
> > 
> > > +	if (ret < 0) {
> > > +		dev_err(priv->dev, "no link freq control in subdev %s\n",
> > > +			source->name);
> > > +		return ret;
> > > +	}
> > > +
> > > +	format = rcar_csi2_code_to_fmt(mf->code);
> > > +	if (!format) {
> > > +		dev_err(priv->dev, "Unknown format: %d\n", mf->code);
> > > +		return -EINVAL;
> > > +	}
> > > +
> > > +	mbps = ctrl.value64 * format->bpp;
> > > +	do_div(mbps, priv->lanes * 1000000);
> > > +
> > > +	for (hsfreq = phypll_hsfreqrange_map; hsfreq->mbps != 0; hsfreq++)
> > > +		if (hsfreq->mbps >= mbps)
> > > +			break;
> > > +
> > > +	if (!hsfreq->mbps) {
> > > +		dev_err(priv->dev, "Unsupported PHY speed (%llu Mbps)", mbps);
> > > +		return -ERANGE;
> > > +	}
> > > +
> > > +	dev_dbg(priv->dev, "PHY HSFREQRANGE requested %llu got %u Mbps\n", mbps,
> > > +		hsfreq->mbps);
> > > +
> > > +	*phypll = PHYPLL_HSFREQRANGE(hsfreq->reg);
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +static int rcar_csi2_start(struct rcar_csi2 *priv)
> > > +{
> > > +	const struct rcar_csi2_format *format;
> > > +	struct v4l2_subdev_format fmt;
> > > +	struct media_pad *source_pad;
> > > +	struct v4l2_subdev *source = NULL;
> > > +	struct v4l2_mbus_framefmt *mf = &fmt.format;
> > > +	u32 phycnt, phypll, tmp;
> > > +	u32 vcdt = 0, vcdt2 = 0;
> > > +	unsigned int i;
> > > +	int ret;
> > > +
> > > +	source_pad =
> > > +		media_entity_remote_pad(&priv->subdev.entity.pads[RCAR_CSI2_SINK]);
> > 
> > Over 80 characters per line. I think you could split this up differently.
> 
> Will fix.
> 
> > 
> > > +	if (!source_pad) {
> > > +		dev_err(priv->dev, "Could not find remote source pad\n");
> > > +		return -ENODEV;
> > > +	}
> > > +
> > > +	source = media_entity_to_v4l2_subdev(source_pad->entity);
> > > +	if (!source) {
> > > +		dev_err(priv->dev, "Could not find remote subdevice\n");
> > > +		return -ENODEV;
> > > +	}
> > > +
> > > +	dev_dbg(priv->dev, "Using source %s pad: %u\n", source->name,
> > > +		source_pad->index);
> > > +
> > > +	fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
> > > +	fmt.pad = source_pad->index;
> > > +	ret = v4l2_subdev_call(source, pad, get_fmt, NULL, &fmt);
> > > +	if (ret)
> > > +		return ret;
> > > +
> > > +	dev_dbg(priv->dev, "Input size (%dx%d%c)\n", mf->width,
> > > +		mf->height, mf->field == V4L2_FIELD_NONE ? 'p' : 'i');
> > > +
> > > +	/*
> > > +	 * Enable all Virtual Channels
> > > +	 *
> > > +	 * NOTE: I'ts not possible to get individual format for each
> > 
> > "It's"
> 
> Ops.. will fix :-)
> 
> > 
> > > +	 *       source virtual channel. Once this is possible in V4L2
> > > +	 *       it should be used here.
> > > +	 */
> > > +	for (i = 0; i < 4; i++) {
> > > +
> > > +		format = rcar_csi2_code_to_fmt(mf->code);
> > > +		if (!format) {
> > > +			dev_err(priv->dev, "Unsupported media bus format: %d\n",
> > > +				mf->code);
> > > +			return -EINVAL;
> > > +		}
> > > +
> > > +		tmp = VCDT_SEL_VC(i) | VCDT_VCDTN_EN | VCDT_SEL_DTN_ON |
> > > +			VCDT_SEL_DT(format->datatype);
> > > +
> > > +		/* Store in correct reg and offset */
> > > +		if (i < 2)
> > > +			vcdt |= tmp << ((i % 2) * 16);
> > > +		else
> > > +			vcdt2 |= tmp << ((i % 2) * 16);
> > > +	}
> > > +
> > > +	switch (priv->lanes) {
> > > +	case 1:
> > > +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_0;
> > > +		break;
> > > +	case 2:
> > > +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_1 | PHYCNT_ENABLE_0;
> > > +		break;

This is where you assume 1, 2 or 4 lanes. 3 is not included.

> > > +	case 4:
> > > +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_3 | PHYCNT_ENABLE_2 |
> > > +			PHYCNT_ENABLE_1 | PHYCNT_ENABLE_0;
> > > +		break;
> > > +	default:
> > > +		return -EINVAL;
> > > +	}
> > > +
> > > +	ret = rcar_csi2_calc_phypll(priv, source, mf, &phypll);
> > > +	if (ret)
> > > +		return ret;
> > > +
> > > +	/* Init */
> > > +	rcar_csi2_write(priv, TREF_REG, TREF_TREF);
> > > +	rcar_csi2_reset(priv);
> > > +	rcar_csi2_write(priv, PHTC_REG, 0);
> > > +
> > > +	/* Configure */
> > > +	rcar_csi2_write(priv, FLD_REG, FLD_FLD_NUM(2) | FLD_FLD_EN4 |
> > > +			FLD_FLD_EN3 | FLD_FLD_EN2 | FLD_FLD_EN);
> > > +	rcar_csi2_write(priv, VCDT_REG, vcdt);
> > > +	rcar_csi2_write(priv, VCDT2_REG, vcdt2);
> > > +	/* Lanes are zero indexed */
> > > +	rcar_csi2_write(priv, LSWAP_REG,
> > > +			LSWAP_L0SEL(priv->lane_swap[0] - 1) |
> > > +			LSWAP_L1SEL(priv->lane_swap[1] - 1) |
> > > +			LSWAP_L2SEL(priv->lane_swap[2] - 1) |
> > > +			LSWAP_L3SEL(priv->lane_swap[3] - 1));
> > 
> > How are the lanes numbered?
> 
> In the datasheet they are numbered CSIn_DATA{0,1,2,3}.
> 
> > 
> > Do you have a fixed number of lanes per receiver?
> 
> Two different configurations exists a 4-lane CSI-2 receiver and a 2-lane 
> CSI-2 receiver.

Can the PHYs share lanes? This isn't too uncommon in hardware
implementations nowadays and the driver needs to know the split. For that
reason it might be a good idea to number the lanes in a way that they are
independent of the PHY. I.e. you could give them numbers from 0 onwards, and
thus determine the PHY lane split from the lane numbers.

...

> > > +static int rcar_csi2_parse_dt_settings(struct rcar_csi2 *priv)
> > > +{
> > > +	struct v4l2_fwnode_endpoint v4l2_ep;
> > > +	struct device_node *ep;
> > > +	unsigned int i;
> > > +	int ret;
> > > +
> > > +	ep = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0);
> > > +	if (!ep)
> > > +		return -EINVAL;
> > > +
> > > +	ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &v4l2_ep);
> > > +	of_node_put(ep);
> > > +	if (ret) {
> > > +		dev_err(priv->dev, "Could not parse v4l2 endpoint\n");
> > > +		return -EINVAL;
> > > +	}
> > > +
> > > +	if (v4l2_ep.bus_type != V4L2_MBUS_CSI2) {
> > > +		dev_err(priv->dev, "Unsupported media bus type for %s\n",
> > > +			of_node_full_name(ep));
> > > +		return -EINVAL;
> > > +	}
> > > +
> > > +	priv->lanes = v4l2_ep.bus.mipi_csi2.num_data_lanes;
> > > +	if (priv->lanes != 1 && priv->lanes != 2 && priv->lanes != 4) {
> > > +		dev_err(priv->dev, "Unsupported number of data-lanes: %d\n",
> > > +			priv->lanes);
> > > +		return -EINVAL;
> > > +	}
> > > +
> > > +	for (i = 0; i < ARRAY_SIZE(priv->lane_swap); i++) {
> > > +		priv->lane_swap[i] = i < priv->lanes ?
> > > +			v4l2_ep.bus.mipi_csi2.data_lanes[i] : i;
> > > +
> > > +		/* Check for valid lane number */
> > > +		if (priv->lane_swap[i] < 1 || priv->lane_swap[i] > 4) {
> > 
> > Do you also support for three lanes? Based on the code elsewhere, it doesn't
> > seem like that.
> 
> Yes 3-lanes should be supported but I have no way of testing this. But I 
> do belive the code is prepared to handle it, see for example in the 
> driver all logic around priv->lanes variable, am I missing something?

Please see an earlier comment.

-- 
Trevliga hälsningar,

Sakari Ailus
e-mail: sakari.ailus@iki.fi	XMPP: sailus@retiisi.org.uk

Re: [PATCH v7 2/2] media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver driver

[Sakari Ailus]

Hejssan Niklas,

On Thu, Jun 15, 2017 at 10:48:20AM +0200, Niklas S�derlund wrote:
> Hi Sakari,
> 
> Thanks for your comments.
> 
> On 2017-05-29 14:35:16 +0300, Sakari Ailus wrote:
> > Hi Niklas,
> > 
> > A few comments below.
> > 
> > On Wed, May 24, 2017 at 02:13:53AM +0200, Niklas S�derlund wrote:
> > > From: Niklas S�derlund <niklas.soderlund+renesas@ragnatech.se>
> > > 
> > > A V4L2 driver for Renesas R-Car MIPI CSI-2 receiver. The driver
> > > supports the rcar-vin driver on R-Car Gen3 SoCs where separate CSI-2
> > > hardware blocks are connected between the video sources and the video
> > > grabbers (VIN).
> > > 
> > > Driver is based on a prototype by Koji Matsuoka in the Renesas BSP.
> > > 
> > > Signed-off-by: Niklas S�derlund <niklas.soderlund+renesas@ragnatech.se>
> > > ---
> > >  drivers/media/platform/rcar-vin/Kconfig     |  12 +
> > >  drivers/media/platform/rcar-vin/Makefile    |   1 +
> > >  drivers/media/platform/rcar-vin/rcar-csi2.c | 867 ++++++++++++++++++++++++++++
> > >  3 files changed, 880 insertions(+)
> > >  create mode 100644 drivers/media/platform/rcar-vin/rcar-csi2.c
> > > 
> > > diff --git a/drivers/media/platform/rcar-vin/Kconfig b/drivers/media/platform/rcar-vin/Kconfig
> > > index af4c98b44d2e22cb..6875f30c1ae42631 100644
> > > --- a/drivers/media/platform/rcar-vin/Kconfig
> > > +++ b/drivers/media/platform/rcar-vin/Kconfig
> > > @@ -1,3 +1,15 @@
> > > +config VIDEO_RCAR_CSI2
> > > +	tristate "R-Car MIPI CSI-2 Receiver"
> > > +	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && OF
> > > +	depends on ARCH_RENESAS || COMPILE_TEST
> > > +	select V4L2_FWNODE
> > > +	---help---
> > > +	  Support for Renesas R-Car MIPI CSI-2 receiver.
> > > +	  Supports R-Car Gen3 SoCs.
> > > +
> > > +	  To compile this driver as a module, choose M here: the
> > > +	  module will be called rcar-csi2.
> > > +
> > >  config VIDEO_RCAR_VIN
> > >  	tristate "R-Car Video Input (VIN) Driver"
> > >  	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && OF && HAS_DMA && MEDIA_CONTROLLER
> > > diff --git a/drivers/media/platform/rcar-vin/Makefile b/drivers/media/platform/rcar-vin/Makefile
> > > index 48c5632c21dc060b..5ab803d3e7c1aa57 100644
> > > --- a/drivers/media/platform/rcar-vin/Makefile
> > > +++ b/drivers/media/platform/rcar-vin/Makefile
> > > @@ -1,3 +1,4 @@
> > >  rcar-vin-objs = rcar-core.o rcar-dma.o rcar-v4l2.o
> > >  
> > > +obj-$(CONFIG_VIDEO_RCAR_CSI2) += rcar-csi2.o
> > >  obj-$(CONFIG_VIDEO_RCAR_VIN) += rcar-vin.o
> > > diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
> > > new file mode 100644
> > > index 0000000000000000..1175f1fe4b139a13
> > > --- /dev/null
> > > +++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
> > > @@ -0,0 +1,867 @@
> > > +/*
> > > + * Driver for Renesas R-Car MIPI CSI-2 Receiver
> > > + *
> > > + * Copyright (C) 2017 Renesas Electronics Corp.
> > > + *
> > > + * This program is free software; you can redistribute  it and/or modify it
> > > + * under  the terms of  the GNU General  Public License as published by the
> > > + * Free Software Foundation;  either version 2 of the  License, or (at your
> > > + * option) any later version.
> > > + */
> > > +
> > > +#include <linux/delay.h>
> > > +#include <linux/interrupt.h>
> > > +#include <linux/io.h>
> > > +#include <linux/module.h>
> > > +#include <linux/of.h>
> > > +#include <linux/of_device.h>
> > > +#include <linux/of_graph.h>
> > > +#include <linux/platform_device.h>
> > > +#include <linux/pm_runtime.h>
> > > +
> > > +#include <media/v4l2-ctrls.h>
> > > +#include <media/v4l2-device.h>
> > > +#include <media/v4l2-fwnode.h>
> > > +#include <media/v4l2-mc.h>
> > > +#include <media/v4l2-subdev.h>
> > > +
> > > +/* Register offsets and bits */
> > > +
> > > +/* Control Timing Select */
> > > +#define TREF_REG			0x00
> > > +#define TREF_TREF			(1 << 0)
> > > +
> > > +/* Software Reset */
> > > +#define SRST_REG			0x04
> > > +#define SRST_SRST			(1 << 0)
> > > +
> > > +/* PHY Operation Control */
> > > +#define PHYCNT_REG			0x08
> > > +#define PHYCNT_SHUTDOWNZ		(1 << 17)
> > > +#define PHYCNT_RSTZ			(1 << 16)
> > > +#define PHYCNT_ENABLECLK		(1 << 4)
> > > +#define PHYCNT_ENABLE_3			(1 << 3)
> > > +#define PHYCNT_ENABLE_2			(1 << 2)
> > > +#define PHYCNT_ENABLE_1			(1 << 1)
> > > +#define PHYCNT_ENABLE_0			(1 << 0)
> > > +
> > > +/* Checksum Control */
> > > +#define CHKSUM_REG			0x0c
> > > +#define CHKSUM_ECC_EN			(1 << 1)
> > > +#define CHKSUM_CRC_EN			(1 << 0)
> > > +
> > > +/*
> > > + * Channel Data Type Select
> > > + * VCDT[0-15]:  Channel 1 VCDT[16-31]:  Channel 2
> > > + * VCDT2[0-15]: Channel 3 VCDT2[16-31]: Channel 4
> > > + */
> > > +#define VCDT_REG			0x10
> > > +#define VCDT2_REG			0x14
> > > +#define VCDT_VCDTN_EN			(1 << 15)
> > > +#define VCDT_SEL_VC(n)			(((n) & 0x3) << 8)
> > > +#define VCDT_SEL_DTN_ON			(1 << 6)
> > > +#define VCDT_SEL_DT(n)			(((n) & 0x3f) << 0)
> > > +
> > > +/* Frame Data Type Select */
> > > +#define FRDT_REG			0x18
> > > +
> > > +/* Field Detection Control */
> > > +#define FLD_REG				0x1c
> > > +#define FLD_FLD_NUM(n)			(((n) & 0xff) << 16)
> > > +#define FLD_FLD_EN4			(1 << 3)
> > > +#define FLD_FLD_EN3			(1 << 2)
> > > +#define FLD_FLD_EN2			(1 << 1)
> > > +#define FLD_FLD_EN			(1 << 0)
> > > +
> > > +/* Automatic Standby Control */
> > > +#define ASTBY_REG			0x20
> > > +
> > > +/* Long Data Type Setting 0 */
> > > +#define LNGDT0_REG			0x28
> > > +
> > > +/* Long Data Type Setting 1 */
> > > +#define LNGDT1_REG			0x2c
> > > +
> > > +/* Interrupt Enable */
> > > +#define INTEN_REG			0x30
> > > +
> > > +/* Interrupt Source Mask */
> > > +#define INTCLOSE_REG			0x34
> > > +
> > > +/* Interrupt Status Monitor */
> > > +#define INTSTATE_REG			0x38
> > > +
> > > +/* Interrupt Error Status Monitor */
> > > +#define INTERRSTATE_REG			0x3c
> > > +
> > > +/* Short Packet Data */
> > > +#define SHPDAT_REG			0x40
> > > +
> > > +/* Short Packet Count */
> > > +#define SHPCNT_REG			0x44
> > > +
> > > +/* LINK Operation Control */
> > > +#define LINKCNT_REG			0x48
> > > +#define LINKCNT_MONITOR_EN		(1 << 31)
> > > +#define LINKCNT_REG_MONI_PACT_EN	(1 << 25)
> > > +#define LINKCNT_ICLK_NONSTOP		(1 << 24)
> > > +
> > > +/* Lane Swap */
> > > +#define LSWAP_REG			0x4c
> > > +#define LSWAP_L3SEL(n)			(((n) & 0x3) << 6)
> > > +#define LSWAP_L2SEL(n)			(((n) & 0x3) << 4)
> > > +#define LSWAP_L1SEL(n)			(((n) & 0x3) << 2)
> > > +#define LSWAP_L0SEL(n)			(((n) & 0x3) << 0)
> > > +
> > > +/* PHY Test Interface Clear */
> > > +#define PHTC_REG			0x58
> > > +#define PHTC_TESTCLR			(1 << 0)
> > > +
> > > +/* PHY Frequency Control */
> > > +#define PHYPLL_REG			0x68
> > > +#define PHYPLL_HSFREQRANGE(n)		((n) << 16)
> > > +
> > > +struct phypll_hsfreqrange {
> > > +	unsigned int	mbps;
> > > +	unsigned char	reg;
> > > +};
> > > +
> > > +static const struct phypll_hsfreqrange phypll_hsfreqrange_map[] = {
> > > +	{ .mbps =   80,	.reg = 0x00 },
> > > +	{ .mbps =   90,	.reg = 0x10 },
> > > +	{ .mbps =  100,	.reg = 0x20 },
> > > +	{ .mbps =  110,	.reg = 0x30 },
> > > +	{ .mbps =  120,	.reg = 0x01 },
> > > +	{ .mbps =  130,	.reg = 0x11 },
> > > +	{ .mbps =  140,	.reg = 0x21 },
> > > +	{ .mbps =  150,	.reg = 0x31 },
> > > +	{ .mbps =  160,	.reg = 0x02 },
> > > +	{ .mbps =  170,	.reg = 0x12 },
> > > +	{ .mbps =  180,	.reg = 0x22 },
> > > +	{ .mbps =  190,	.reg = 0x32 },
> > > +	{ .mbps =  205,	.reg = 0x03 },
> > > +	{ .mbps =  220,	.reg = 0x13 },
> > > +	{ .mbps =  235,	.reg = 0x23 },
> > > +	{ .mbps =  250,	.reg = 0x33 },
> > > +	{ .mbps =  275,	.reg = 0x04 },
> > > +	{ .mbps =  300,	.reg = 0x14 },
> > > +	{ .mbps =  325,	.reg = 0x05 },
> > > +	{ .mbps =  350,	.reg = 0x15 },
> > > +	{ .mbps =  400,	.reg = 0x25 },
> > > +	{ .mbps =  450,	.reg = 0x06 },
> > > +	{ .mbps =  500,	.reg = 0x16 },
> > > +	{ .mbps =  550,	.reg = 0x07 },
> > > +	{ .mbps =  600,	.reg = 0x17 },
> > > +	{ .mbps =  650,	.reg = 0x08 },
> > > +	{ .mbps =  700,	.reg = 0x18 },
> > > +	{ .mbps =  750,	.reg = 0x09 },
> > > +	{ .mbps =  800,	.reg = 0x19 },
> > > +	{ .mbps =  850,	.reg = 0x29 },
> > > +	{ .mbps =  900,	.reg = 0x39 },
> > > +	{ .mbps =  950,	.reg = 0x0A },
> > > +	{ .mbps = 1000,	.reg = 0x1A },
> > > +	{ .mbps = 1050,	.reg = 0x2A },
> > > +	{ .mbps = 1100,	.reg = 0x3A },
> > > +	{ .mbps = 1150,	.reg = 0x0B },
> > > +	{ .mbps = 1200,	.reg = 0x1B },
> > > +	{ .mbps = 1250,	.reg = 0x2B },
> > > +	{ .mbps = 1300,	.reg = 0x3B },
> > > +	{ .mbps = 1350,	.reg = 0x0C },
> > > +	{ .mbps = 1400,	.reg = 0x1C },
> > > +	{ .mbps = 1450,	.reg = 0x2C },
> > > +	{ .mbps = 1500,	.reg = 0x3C },
> > > +	/* guard */
> > > +	{ .mbps =   0,	.reg = 0x00 },
> > > +};
> > > +
> > > +/* PHY ESC Error Monitor */
> > > +#define PHEERM_REG			0x74
> > > +
> > > +/* PHY Clock Lane Monitor */
> > > +#define PHCLM_REG			0x78
> > > +
> > > +/* PHY Data Lane Monitor */
> > > +#define PHDLM_REG			0x7c
> > > +
> > > +struct rcar_csi2_format {
> > > +	unsigned int code;
> > > +	unsigned int datatype;
> > > +	unsigned int bpp;
> > > +};
> > > +
> > > +static const struct rcar_csi2_format rcar_csi2_formats[] = {
> > > +	{ .code = MEDIA_BUS_FMT_RGB888_1X24,	.datatype = 0x24, .bpp = 24},
> > > +	{ .code = MEDIA_BUS_FMT_UYVY8_1X16,	.datatype = 0x1e, .bpp = 8 },
> > > +	{ .code = MEDIA_BUS_FMT_UYVY8_2X8,	.datatype = 0x1e, .bpp = 8 },
> > > +	{ .code = MEDIA_BUS_FMT_YUYV10_2X10,	.datatype = 0x1e, .bpp = 8 },
> > > +};
> > > +
> > > +static const struct rcar_csi2_format *rcar_csi2_code_to_fmt(unsigned int code)
> > > +{
> > > +	int i;
> > > +
> > > +	for (i = 0; i < ARRAY_SIZE(rcar_csi2_formats); i++)
> > > +		if (rcar_csi2_formats[i].code == code)
> > > +			return rcar_csi2_formats + i;
> > > +	return NULL;
> > > +}
> > > +
> > > +enum rcar_csi2_pads {
> > > +	RCAR_CSI2_SINK,
> > > +	RCAR_CSI2_SOURCE_VC0,
> > > +	RCAR_CSI2_SOURCE_VC1,
> > > +	RCAR_CSI2_SOURCE_VC2,
> > > +	RCAR_CSI2_SOURCE_VC3,
> > > +	NR_OF_RCAR_CSI2_PAD,
> > > +};
> > > +
> > > +struct rcar_csi2 {
> > > +	struct device *dev;
> > > +	void __iomem *base;
> > > +
> > > +	unsigned short lanes;
> > > +	unsigned char lane_swap[4];
> > > +
> > > +	struct v4l2_subdev subdev;
> > > +	struct media_pad pads[NR_OF_RCAR_CSI2_PAD];
> > > +
> > > +	struct v4l2_mbus_framefmt mf;
> > > +
> > > +	struct mutex lock;
> > > +	int stream_count;
> > > +
> > > +	struct v4l2_async_notifier notifier;
> > > +	struct {
> > > +		struct v4l2_async_subdev asd;
> > > +		struct v4l2_subdev *subdev;
> > > +		struct fwnode_handle *fwnode;
> > > +		unsigned int source_pad;
> > > +	} remote;
> > > +};
> > > +
> > > +static inline struct rcar_csi2 *sd_to_csi2(struct v4l2_subdev *sd)
> > > +{
> > > +	return container_of(sd, struct rcar_csi2, subdev);
> > > +}
> > > +
> > > +static u32 rcar_csi2_read(struct rcar_csi2 *priv, unsigned int reg)
> > > +{
> > > +	return ioread32(priv->base + reg);
> > > +}
> > > +
> > > +static void rcar_csi2_write(struct rcar_csi2 *priv, unsigned int reg, u32 data)
> > > +{
> > > +	iowrite32(data, priv->base + reg);
> > > +}
> > > +
> > > +static void rcar_csi2_reset(struct rcar_csi2 *priv)
> > > +{
> > > +	rcar_csi2_write(priv, SRST_REG, SRST_SRST);
> > > +	rcar_csi2_write(priv, SRST_REG, 0);
> > > +}
> > > +
> > > +static int rcar_csi2_wait_phy_start(struct rcar_csi2 *priv)
> > > +{
> > > +	int timeout;
> > > +
> > > +	/* Wait for the clock and data lanes to enter LP-11 state. */
> > > +	for (timeout = 100; timeout >= 0; timeout--) {
> > > +		const u32 lane_mask = (1 << priv->lanes) - 1;
> > > +
> > > +		if ((rcar_csi2_read(priv, PHCLM_REG) & 1) == 1 &&
> > > +		    (rcar_csi2_read(priv, PHDLM_REG) & lane_mask) == lane_mask)
> > > +			return 0;
> > > +
> > > +		msleep(20);
> > > +	}
> > > +
> > > +	dev_err(priv->dev, "Timeout waiting for LP-11 state\n");
> > > +
> > > +	return -ETIMEDOUT;
> > > +}
> > > +
> > > +static int rcar_csi2_calc_phypll(struct rcar_csi2 *priv,
> > > +				 struct v4l2_subdev *source,
> > > +				 struct v4l2_mbus_framefmt *mf,
> > > +				 u32 *phypll)
> > > +{
> > > +	const struct phypll_hsfreqrange *hsfreq;
> > > +	const struct rcar_csi2_format *format;
> > > +	struct v4l2_ext_controls ctrls;
> > > +	struct v4l2_ext_control ctrl;
> > > +	u64 mbps;
> > > +	int ret;
> > > +
> > > +	memset(&ctrls, 0, sizeof(ctrls));
> > > +	memset(&ctrl, 0, sizeof(ctrl));
> > > +
> > > +	ctrl.id = V4L2_CID_PIXEL_RATE;
> > > +
> > > +	ctrls.count = 1;
> > > +	ctrls.controls = &ctrl;
> > > +
> > > +	ret = v4l2_g_ext_ctrls(source->ctrl_handler, &ctrls);
> > 
> > v4l2_ctrl_g_ctrl_int64(), please. Or do I miss something?
> 
> Thanks will fix.
> 
> > 
> > > +	if (ret < 0) {
> > > +		dev_err(priv->dev, "no link freq control in subdev %s\n",
> > > +			source->name);
> > > +		return ret;
> > > +	}
> > > +
> > > +	format = rcar_csi2_code_to_fmt(mf->code);
> > > +	if (!format) {
> > > +		dev_err(priv->dev, "Unknown format: %d\n", mf->code);
> > > +		return -EINVAL;
> > > +	}
> > > +
> > > +	mbps = ctrl.value64 * format->bpp;
> > > +	do_div(mbps, priv->lanes * 1000000);
> > > +
> > > +	for (hsfreq = phypll_hsfreqrange_map; hsfreq->mbps != 0; hsfreq++)
> > > +		if (hsfreq->mbps >= mbps)
> > > +			break;
> > > +
> > > +	if (!hsfreq->mbps) {
> > > +		dev_err(priv->dev, "Unsupported PHY speed (%llu Mbps)", mbps);
> > > +		return -ERANGE;
> > > +	}
> > > +
> > > +	dev_dbg(priv->dev, "PHY HSFREQRANGE requested %llu got %u Mbps\n", mbps,
> > > +		hsfreq->mbps);
> > > +
> > > +	*phypll = PHYPLL_HSFREQRANGE(hsfreq->reg);
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +static int rcar_csi2_start(struct rcar_csi2 *priv)
> > > +{
> > > +	const struct rcar_csi2_format *format;
> > > +	struct v4l2_subdev_format fmt;
> > > +	struct media_pad *source_pad;
> > > +	struct v4l2_subdev *source = NULL;
> > > +	struct v4l2_mbus_framefmt *mf = &fmt.format;
> > > +	u32 phycnt, phypll, tmp;
> > > +	u32 vcdt = 0, vcdt2 = 0;
> > > +	unsigned int i;
> > > +	int ret;
> > > +
> > > +	source_pad =
> > > +		media_entity_remote_pad(&priv->subdev.entity.pads[RCAR_CSI2_SINK]);
> > 
> > Over 80 characters per line. I think you could split this up differently.
> 
> Will fix.
> 
> > 
> > > +	if (!source_pad) {
> > > +		dev_err(priv->dev, "Could not find remote source pad\n");
> > > +		return -ENODEV;
> > > +	}
> > > +
> > > +	source = media_entity_to_v4l2_subdev(source_pad->entity);
> > > +	if (!source) {
> > > +		dev_err(priv->dev, "Could not find remote subdevice\n");
> > > +		return -ENODEV;
> > > +	}
> > > +
> > > +	dev_dbg(priv->dev, "Using source %s pad: %u\n", source->name,
> > > +		source_pad->index);
> > > +
> > > +	fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
> > > +	fmt.pad = source_pad->index;
> > > +	ret = v4l2_subdev_call(source, pad, get_fmt, NULL, &fmt);
> > > +	if (ret)
> > > +		return ret;
> > > +
> > > +	dev_dbg(priv->dev, "Input size (%dx%d%c)\n", mf->width,
> > > +		mf->height, mf->field == V4L2_FIELD_NONE ? 'p' : 'i');
> > > +
> > > +	/*
> > > +	 * Enable all Virtual Channels
> > > +	 *
> > > +	 * NOTE: I'ts not possible to get individual format for each
> > 
> > "It's"
> 
> Ops.. will fix :-)
> 
> > 
> > > +	 *       source virtual channel. Once this is possible in V4L2
> > > +	 *       it should be used here.
> > > +	 */
> > > +	for (i = 0; i < 4; i++) {
> > > +
> > > +		format = rcar_csi2_code_to_fmt(mf->code);
> > > +		if (!format) {
> > > +			dev_err(priv->dev, "Unsupported media bus format: %d\n",
> > > +				mf->code);
> > > +			return -EINVAL;
> > > +		}
> > > +
> > > +		tmp = VCDT_SEL_VC(i) | VCDT_VCDTN_EN | VCDT_SEL_DTN_ON |
> > > +			VCDT_SEL_DT(format->datatype);
> > > +
> > > +		/* Store in correct reg and offset */
> > > +		if (i < 2)
> > > +			vcdt |= tmp << ((i % 2) * 16);
> > > +		else
> > > +			vcdt2 |= tmp << ((i % 2) * 16);
> > > +	}
> > > +
> > > +	switch (priv->lanes) {
> > > +	case 1:
> > > +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_0;
> > > +		break;
> > > +	case 2:
> > > +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_1 | PHYCNT_ENABLE_0;
> > > +		break;

This is where you assume 1, 2 or 4 lanes. 3 is not included.

> > > +	case 4:
> > > +		phycnt = PHYCNT_ENABLECLK | PHYCNT_ENABLE_3 | PHYCNT_ENABLE_2 |
> > > +			PHYCNT_ENABLE_1 | PHYCNT_ENABLE_0;
> > > +		break;
> > > +	default:
> > > +		return -EINVAL;
> > > +	}
> > > +
> > > +	ret = rcar_csi2_calc_phypll(priv, source, mf, &phypll);
> > > +	if (ret)
> > > +		return ret;
> > > +
> > > +	/* Init */
> > > +	rcar_csi2_write(priv, TREF_REG, TREF_TREF);
> > > +	rcar_csi2_reset(priv);
> > > +	rcar_csi2_write(priv, PHTC_REG, 0);
> > > +
> > > +	/* Configure */
> > > +	rcar_csi2_write(priv, FLD_REG, FLD_FLD_NUM(2) | FLD_FLD_EN4 |
> > > +			FLD_FLD_EN3 | FLD_FLD_EN2 | FLD_FLD_EN);
> > > +	rcar_csi2_write(priv, VCDT_REG, vcdt);
> > > +	rcar_csi2_write(priv, VCDT2_REG, vcdt2);
> > > +	/* Lanes are zero indexed */
> > > +	rcar_csi2_write(priv, LSWAP_REG,
> > > +			LSWAP_L0SEL(priv->lane_swap[0] - 1) |
> > > +			LSWAP_L1SEL(priv->lane_swap[1] - 1) |
> > > +			LSWAP_L2SEL(priv->lane_swap[2] - 1) |
> > > +			LSWAP_L3SEL(priv->lane_swap[3] - 1));
> > 
> > How are the lanes numbered?
> 
> In the datasheet they are numbered CSIn_DATA{0,1,2,3}.
> 
> > 
> > Do you have a fixed number of lanes per receiver?
> 
> Two different configurations exists a 4-lane CSI-2 receiver and a 2-lane 
> CSI-2 receiver.

Can the PHYs share lanes? This isn't too uncommon in hardware
implementations nowadays and the driver needs to know the split. For that
reason it might be a good idea to number the lanes in a way that they are
independent of the PHY. I.e. you could give them numbers from 0 onwards, and
thus determine the PHY lane split from the lane numbers.

...

> > > +static int rcar_csi2_parse_dt_settings(struct rcar_csi2 *priv)
> > > +{
> > > +	struct v4l2_fwnode_endpoint v4l2_ep;
> > > +	struct device_node *ep;
> > > +	unsigned int i;
> > > +	int ret;
> > > +
> > > +	ep = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0);
> > > +	if (!ep)
> > > +		return -EINVAL;
> > > +
> > > +	ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &v4l2_ep);
> > > +	of_node_put(ep);
> > > +	if (ret) {
> > > +		dev_err(priv->dev, "Could not parse v4l2 endpoint\n");
> > > +		return -EINVAL;
> > > +	}
> > > +
> > > +	if (v4l2_ep.bus_type != V4L2_MBUS_CSI2) {
> > > +		dev_err(priv->dev, "Unsupported media bus type for %s\n",
> > > +			of_node_full_name(ep));
> > > +		return -EINVAL;
> > > +	}
> > > +
> > > +	priv->lanes = v4l2_ep.bus.mipi_csi2.num_data_lanes;
> > > +	if (priv->lanes != 1 && priv->lanes != 2 && priv->lanes != 4) {
> > > +		dev_err(priv->dev, "Unsupported number of data-lanes: %d\n",
> > > +			priv->lanes);
> > > +		return -EINVAL;
> > > +	}
> > > +
> > > +	for (i = 0; i < ARRAY_SIZE(priv->lane_swap); i++) {
> > > +		priv->lane_swap[i] = i < priv->lanes ?
> > > +			v4l2_ep.bus.mipi_csi2.data_lanes[i] : i;
> > > +
> > > +		/* Check for valid lane number */
> > > +		if (priv->lane_swap[i] < 1 || priv->lane_swap[i] > 4) {
> > 
> > Do you also support for three lanes? Based on the code elsewhere, it doesn't
> > seem like that.
> 
> Yes 3-lanes should be supported but I have no way of testing this. But I 
> do belive the code is prepared to handle it, see for example in the 
> driver all logic around priv->lanes variable, am I missing something?

Please see an earlier comment.

-- 
Trevliga h�lsningar,

Sakari Ailus
e-mail: sakari.ailus@iki.fi	XMPP: sailus@retiisi.org.uk