[PATCH v4 0/6] dt-bindings: add bindings for USB physical connector

[PATCH v4 0/6] dt-bindings: add bindings for USB physical connector

[Andrzej Hajda]

Hi,

Thanks for reviews of previous iterations.

This patchset introduces USB physical connector bindings, together with
working example.
I have removed RFC prefix - the patchset seems to be heading
to a happy end :)

v4: improved binding descriptions, added missing reg in dts.
v3: Separate binding for Samsung 11-pin connector, added full-blown USB-C
    example.
v2: I have addressed comments by Rob and Laurent, thanks 

Changes in datail are described in the patches.

Regards
Andrzej


Andrzej Hajda (5):
  dt-bindings: add bindings for USB physical connector
  dt-bindings: add bindings for Samsung micro-USB 11-pin connector
  arm64: dts: exynos: add micro-USB connector node to TM2 platforms
  arm64: dts: exynos: add OF graph between MHL and USB connector
  extcon: add possibility to get extcon device by OF node

Maciej Purski (1):
  drm/bridge/sii8620: use micro-USB cable detection logic to detect MHL

 .../connector/samsung,usb-connector-11pin.txt      | 49 +++++++++++
 .../bindings/connector/usb-connector.txt           | 75 +++++++++++++++++
 .../boot/dts/exynos/exynos5433-tm2-common.dtsi     | 39 ++++++++-
 drivers/extcon/extcon.c                            | 44 +++++++---
 drivers/gpu/drm/bridge/sil-sii8620.c               | 97 +++++++++++++++++++++-
 include/linux/extcon.h                             |  6 ++
 6 files changed, 294 insertions(+), 16 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/connector/samsung,usb-connector-11pin.txt
 create mode 100644 Documentation/devicetree/bindings/connector/usb-connector.txt

-- 
2.16.1

[PATCH v4 1/6] dt-bindings: add bindings for USB physical connector

[Andrzej Hajda]

These bindings allow to describe most known standard USB connectors
and it should be possible to extend it if necessary.
USB connectors, beside USB can be used to route other protocols,
for example UART, Audio, MHL. In such case every device passing data
through the connector should have appropriate graph bindings.

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
---
v4:
- improved 'type' description (Rob),
- improved description of 2nd example (Rob).
v3:
- removed MHL port (samsung connector will have separate bindings),
- added 2nd example for USB-C,
- improved formatting.
v2:
- moved connector type(A,B,C) to compatible string (Rob),
- renamed size property to type (Rob),
- changed type description to be less confusing (Laurent),
- removed vendor specific compatibles (implied by graph port number),
- added requirement of connector being a child of IC (Rob),
- removed max-mode (subtly suggested by Rob, it should be detected anyway
  by USB Controller in runtime, downside is that device is not able to
  report its real capabilities, maybe better would be to make it optional(?)),
- assigned port numbers to data buses (Rob).

Regards
Andrzej
---
 .../bindings/connector/usb-connector.txt           | 75 ++++++++++++++++++++++
 1 file changed, 75 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/connector/usb-connector.txt

diff --git a/Documentation/devicetree/bindings/connector/usb-connector.txt b/Documentation/devicetree/bindings/connector/usb-connector.txt
new file mode 100644
index 000000000000..e1463f14af38
--- /dev/null
+++ b/Documentation/devicetree/bindings/connector/usb-connector.txt
@@ -0,0 +1,75 @@
+USB Connector
+=============
+
+USB connector node represents physical USB connector. It should be
+a child of USB interface controller.
+
+Required properties:
+- compatible: describes type of the connector, must be one of:
+    "usb-a-connector",
+    "usb-b-connector",
+    "usb-c-connector".
+
+Optional properties:
+- label: symbolic name for the connector,
+- type: size of the connector, should be specified in case of USB-A, USB-B
+  non-fullsize connectors: "mini", "micro".
+
+Required nodes:
+- any data bus to the connector should be modeled using the OF graph bindings
+  specified in bindings/graph.txt, unless the bus is between parent node and
+  the connector. Since single connector can have multpile data buses every bus
+  has assigned OF graph port number as follows:
+    0: High Speed (HS), present in all connectors,
+    1: Super Speed (SS), present in SS capable connectors,
+    2: Sideband use (SBU), present in USB-C.
+
+Examples
+--------
+
+1. Micro-USB connector with HS lines routed via controller (MUIC):
+
+muic-max77843@66 {
+	...
+	usb_con: connector {
+		compatible = "usb-b-connector";
+		label = "micro-USB";
+		type = "micro";
+	};
+};
+
+2. USB-C connector attached to CC controller (s2mm005), HS lines routed
+to companion PMIC (max77865), SS lines to USB3 PHY and SBU to DisplayPort.
+DisplayPort video lines are routed to the connector via SS mux in USB3 PHY.
+
+ccic: s2mm005@33 {
+	...
+	usb_con: connector {
+		compatible = "usb-c-connector";
+		label = "USB-C";
+
+		ports {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			port@0 {
+				reg = <0>;
+				usb_con_hs: endpoint {
+					remote-endpoint = <&max77865_usbc_hs>;
+				};
+			};
+			port@1 {
+				reg = <1>;
+				usb_con_ss: endpoint {
+					remote-endpoint = <&usbdrd_phy_ss>;
+				};
+			};
+			port@2 {
+				reg = <2>;
+				usb_con_sbu: endpoint {
+					remote-endpoint = <&dp_aux>;
+				};
+			};
+		};
+	};
+};
-- 
2.16.1

[PATCH v4 2/6] dt-bindings: add bindings for Samsung micro-USB 11-pin connector

[Andrzej Hajda]

Samsung micro-USB 11-pin connector beside standard micro-USB pins,
has pins dedicated to route MHL traffic.

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Reviewed-by: Rob Herring <robh@kernel.org>
---
v4:
- removed description of property inherited from usb-connector (Rob),
- fixed example description.
---
 .../connector/samsung,usb-connector-11pin.txt      | 49 ++++++++++++++++++++++
 1 file changed, 49 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/connector/samsung,usb-connector-11pin.txt

diff --git a/Documentation/devicetree/bindings/connector/samsung,usb-connector-11pin.txt b/Documentation/devicetree/bindings/connector/samsung,usb-connector-11pin.txt
new file mode 100644
index 000000000000..22256e295a7a
--- /dev/null
+++ b/Documentation/devicetree/bindings/connector/samsung,usb-connector-11pin.txt
@@ -0,0 +1,49 @@
+Samsung micro-USB 11-pin connector
+==================================
+
+Samsung micro-USB 11-pin connector is an extension of micro-USB connector.
+It is present in multiple Samsung mobile devices.
+It has additional pins to route MHL traffic simultanously with USB.
+
+The bindings are superset of usb-connector bindings for micro-USB connector[1].
+
+Required properties:
+- compatible: must be: "samsung,usb-connector-11pin", "usb-b-connector",
+- type: must be "micro".
+
+Required nodes:
+- any data bus to the connector should be modeled using the OF graph bindings
+  specified in bindings/graph.txt, unless the bus is between parent node and
+  the connector. Since single connector can have multpile data buses every bus
+  has assigned OF graph port number as follows:
+    0: High Speed (HS),
+    3: Mobile High-Definition Link (MHL), specific to 11-pin Samsung micro-USB.
+
+[1]: bindings/connector/usb-connector.txt
+
+Example
+-------
+
+Micro-USB connector with HS lines routed via controller (MUIC) and MHL lines
+connected to HDMI-MHL bridge (sii8620):
+
+muic-max77843@66 {
+	...
+	usb_con: connector {
+		compatible = "samsung,usb-connector-11pin", "usb-b-connector";
+		label = "micro-USB";
+		type = "micro";
+
+		ports {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			port@3 {
+				reg = <3>;
+				usb_con_mhl: endpoint {
+					remote-endpoint = <&sii8620_mhl>;
+				};
+			};
+		};
+	};
+};
-- 
2.16.1

[PATCH v4 3/6] arm64: dts: exynos: add micro-USB connector node to TM2 platforms

[Andrzej Hajda]

Since USB connector bindings are available we can describe it on TM2(e).

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
---
 arch/arm64/boot/dts/exynos/exynos5433-tm2-common.dtsi | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/arch/arm64/boot/dts/exynos/exynos5433-tm2-common.dtsi b/arch/arm64/boot/dts/exynos/exynos5433-tm2-common.dtsi
index 0b61dda99569..f604f6b1a9c2 100644
--- a/arch/arm64/boot/dts/exynos/exynos5433-tm2-common.dtsi
+++ b/arch/arm64/boot/dts/exynos/exynos5433-tm2-common.dtsi
@@ -836,6 +836,13 @@
 
 		muic: max77843-muic {
 			compatible = "maxim,max77843-muic";
+
+			musb_con: musb_connector {
+				compatible = "samsung,usb-connector-11pin",
+					     "usb-b-connector";
+				label = "micro-USB";
+				type = "micro";
+			};
 		};
 
 		regulators {
-- 
2.16.1

[PATCH v4 4/6] arm64: dts: exynos: add OF graph between MHL and USB connector

[Andrzej Hajda]

OF graph describes MHL data lanes between MHL and respective USB
connector.

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
---
v4:
- added missing reg property in connector's port node (Krzysztof)
---
 .../boot/dts/exynos/exynos5433-tm2-common.dtsi     | 32 ++++++++++++++++++++--
 1 file changed, 29 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/boot/dts/exynos/exynos5433-tm2-common.dtsi b/arch/arm64/boot/dts/exynos/exynos5433-tm2-common.dtsi
index f604f6b1a9c2..2ed506df94d0 100644
--- a/arch/arm64/boot/dts/exynos/exynos5433-tm2-common.dtsi
+++ b/arch/arm64/boot/dts/exynos/exynos5433-tm2-common.dtsi
@@ -817,9 +817,22 @@
 		clocks = <&pmu_system_controller 0>;
 		clock-names = "xtal";
 
-		port {
-			mhl_to_hdmi: endpoint {
-				remote-endpoint = <&hdmi_to_mhl>;
+		ports {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			port@0 {
+				reg = <0>;
+				mhl_to_hdmi: endpoint {
+					remote-endpoint = <&hdmi_to_mhl>;
+				};
+			};
+
+			port@1 {
+				reg = <1>;
+				mhl_to_musb_con: endpoint {
+					remote-endpoint = <&musb_con_to_mhl>;
+				};
 			};
 		};
 	};
@@ -842,6 +855,19 @@
 					     "usb-b-connector";
 				label = "micro-USB";
 				type = "micro";
+
+				ports {
+					#address-cells = <1>;
+					#size-cells = <0>;
+
+					port@3 {
+						reg = <3>;
+						musb_con_to_mhl: endpoint {
+							remote-endpoint = <&mhl_to_musb_con>;
+						};
+					};
+				};
+			};
 			};
 		};
 
-- 
2.16.1

Re: [PATCH v4 4/6] arm64: dts: exynos: add OF graph between MHL and USB connector

[kbuild test robot]

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Hi Andrzej,

I love your patch! Yet something to improve:

[auto build test ERROR on robh/for-next]
[also build test ERROR on v4.16-rc2 next-20180221]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Andrzej-Hajda/dt-bindings-add-bindings-for-USB-physical-connector/20180221-185759
base:   https://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git for-next
config: arm64-defconfig (attached as .config)
compiler: aarch64-linux-gnu-gcc (Debian 7.2.0-11) 7.2.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=arm64 

All errors (new ones prefixed by >>):

>> Error: arch/arm64/boot/dts/exynos/exynos5433-tm2-common.dtsi:864.1-2 syntax error
   FATAL ERROR: Unable to parse input tree

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 38172 bytes --]

Re: [PATCH v4 4/6] arm64: dts: exynos: add OF graph between MHL and USB connector

[Krzysztof Kozlowski]

On Wed, Feb 21, 2018 at 9:55 AM, Andrzej Hajda <a.hajda@samsung.com> wrote:
> OF graph describes MHL data lanes between MHL and respective USB
> connector.
>
> Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
> ---
> v4:
> - added missing reg property in connector's port node (Krzysztof)
> ---
>  .../boot/dts/exynos/exynos5433-tm2-common.dtsi     | 32 ++++++++++++++++++++--
>  1 file changed, 29 insertions(+), 3 deletions(-)

You have a duplicated '};' so kbuild complains so I assume there will
be next iteration of this. Beside that I am okay with both, so I will
take next version when your bindings and driver changes get
acked/accepted.

Best Regards,
Krzysztof

Re: [PATCH v4 4/6] arm64: dts: exynos: add OF graph between MHL and USB connector

[Andrzej Hajda]

On 26.02.2018 16:21, Krzysztof Kozlowski wrote:
> On Wed, Feb 21, 2018 at 9:55 AM, Andrzej Hajda <a.hajda@samsung.com> wrote:
>> OF graph describes MHL data lanes between MHL and respective USB
>> connector.
>>
>> Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
>> ---
>> v4:
>> - added missing reg property in connector's port node (Krzysztof)
>> ---
>>  .../boot/dts/exynos/exynos5433-tm2-common.dtsi     | 32 ++++++++++++++++++++--
>>  1 file changed, 29 insertions(+), 3 deletions(-)
> You have a duplicated '};' so kbuild complains so I assume there will
> be next iteration of this. Beside that I am okay with both, so I will
> take next version when your bindings and driver changes get
> acked/accepted.

Yes, test robot already reported it, thanks for looking at it.
I have postponed next iteration in case anything new is spotted, but
since it is calm I will send it in few minutes.

Regards
Andrzej

>
> Best Regards,
> Krzysztof
> --
> To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>
>
>

Re: [PATCH v4 4/6] arm64: dts: exynos: add OF graph between MHL and USB connector

[Rob Herring]

On Wed, Feb 21, 2018 at 2:55 AM, Andrzej Hajda <a.hajda@samsung.com> wrote:
> OF graph describes MHL data lanes between MHL and respective USB
> connector.
>
> Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
> ---
> v4:
> - added missing reg property in connector's port node (Krzysztof)
> ---
>  .../boot/dts/exynos/exynos5433-tm2-common.dtsi     | 32 ++++++++++++++++++++--
>  1 file changed, 29 insertions(+), 3 deletions(-)
>
> diff --git a/arch/arm64/boot/dts/exynos/exynos5433-tm2-common.dtsi b/arch/arm64/boot/dts/exynos/exynos5433-tm2-common.dtsi
> index f604f6b1a9c2..2ed506df94d0 100644
> --- a/arch/arm64/boot/dts/exynos/exynos5433-tm2-common.dtsi
> +++ b/arch/arm64/boot/dts/exynos/exynos5433-tm2-common.dtsi
> @@ -817,9 +817,22 @@
>                 clocks = <&pmu_system_controller 0>;
>                 clock-names = "xtal";
>
> -               port {
> -                       mhl_to_hdmi: endpoint {
> -                               remote-endpoint = <&hdmi_to_mhl>;
> +               ports {
> +                       #address-cells = <1>;
> +                       #size-cells = <0>;
> +
> +                       port@0 {
> +                               reg = <0>;
> +                               mhl_to_hdmi: endpoint {
> +                                       remote-endpoint = <&hdmi_to_mhl>;
> +                               };
> +                       };
> +
> +                       port@1 {
> +                               reg = <1>;
> +                               mhl_to_musb_con: endpoint {
> +                                       remote-endpoint = <&musb_con_to_mhl>;
> +                               };

These ports are mutually exclusive, right? If so, it should be 1 port
with 2 endpoints. Ports should represent independent data flows.
Something muxed or replicated (1 to many connection) should be be
endpoints.

Rob

Re: [PATCH v4 4/6] arm64: dts: exynos: add OF graph between MHL and USB connector

[Andrzej Hajda]

On 27.02.2018 22:24, Rob Herring wrote:
> On Wed, Feb 21, 2018 at 2:55 AM, Andrzej Hajda <a.hajda@samsung.com> wrote:
>> OF graph describes MHL data lanes between MHL and respective USB
>> connector.
>>
>> Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
>> ---
>> v4:
>> - added missing reg property in connector's port node (Krzysztof)
>> ---
>>  .../boot/dts/exynos/exynos5433-tm2-common.dtsi     | 32 ++++++++++++++++++++--
>>  1 file changed, 29 insertions(+), 3 deletions(-)
>>
>> diff --git a/arch/arm64/boot/dts/exynos/exynos5433-tm2-common.dtsi b/arch/arm64/boot/dts/exynos/exynos5433-tm2-common.dtsi
>> index f604f6b1a9c2..2ed506df94d0 100644
>> --- a/arch/arm64/boot/dts/exynos/exynos5433-tm2-common.dtsi
>> +++ b/arch/arm64/boot/dts/exynos/exynos5433-tm2-common.dtsi
>> @@ -817,9 +817,22 @@
>>                 clocks = <&pmu_system_controller 0>;
>>                 clock-names = "xtal";
>>
>> -               port {
>> -                       mhl_to_hdmi: endpoint {
>> -                               remote-endpoint = <&hdmi_to_mhl>;
>> +               ports {
>> +                       #address-cells = <1>;
>> +                       #size-cells = <0>;
>> +
>> +                       port@0 {
>> +                               reg = <0>;
>> +                               mhl_to_hdmi: endpoint {
>> +                                       remote-endpoint = <&hdmi_to_mhl>;
>> +                               };
>> +                       };
>> +
>> +                       port@1 {
>> +                               reg = <1>;
>> +                               mhl_to_musb_con: endpoint {
>> +                                       remote-endpoint = <&musb_con_to_mhl>;
>> +                               };
> These ports are mutually exclusive, right? If so, it should be 1 port
> with 2 endpoints. Ports should represent independent data flows.
> Something muxed or replicated (1 to many connection) should be be
> endpoints.

No, this is HDMI -> MHL bridge, so port 0 is HDMI input, and port 1 is
MHL output.

Regards
Andrzej

>
> Rob
>
>
>

[PATCH v4 5/6] extcon: add possibility to get extcon device by OF node

[Andrzej Hajda]

Since extcon property is not allowed in DT, extcon subsystem requires
another way to get extcon device. Lets try the simplest approach - get
edev by of_node.

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
---
v2: changed label to follow local convention (Chanwoo)
---
 drivers/extcon/extcon.c | 44 ++++++++++++++++++++++++++++++++++----------
 include/linux/extcon.h  |  6 ++++++
 2 files changed, 40 insertions(+), 10 deletions(-)

diff --git a/drivers/extcon/extcon.c b/drivers/extcon/extcon.c
index cb38c2747684..c4972c4cb3bd 100644
--- a/drivers/extcon/extcon.c
+++ b/drivers/extcon/extcon.c
@@ -1336,6 +1336,28 @@ void extcon_dev_unregister(struct extcon_dev *edev)
 EXPORT_SYMBOL_GPL(extcon_dev_unregister);
 
 #ifdef CONFIG_OF
+
+/*
+ * extcon_get_edev_by_of_node - Get the extcon device from devicetree.
+ * @node	: OF node identyfying edev
+ *
+ * Return the pointer of extcon device if success or ERR_PTR(err) if fail.
+ */
+struct extcon_dev *extcon_get_edev_by_of_node(struct device_node *node)
+{
+	struct extcon_dev *edev;
+
+	mutex_lock(&extcon_dev_list_lock);
+	list_for_each_entry(edev, &extcon_dev_list, entry)
+		if (edev->dev.parent && edev->dev.parent->of_node == node)
+			goto out;
+	edev = ERR_PTR(-EPROBE_DEFER);
+out:
+	mutex_unlock(&extcon_dev_list_lock);
+
+	return edev;
+}
+
 /*
  * extcon_get_edev_by_phandle - Get the extcon device from devicetree.
  * @dev		: the instance to the given device
@@ -1363,25 +1385,27 @@ struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index)
 		return ERR_PTR(-ENODEV);
 	}
 
-	mutex_lock(&extcon_dev_list_lock);
-	list_for_each_entry(edev, &extcon_dev_list, entry) {
-		if (edev->dev.parent && edev->dev.parent->of_node == node) {
-			mutex_unlock(&extcon_dev_list_lock);
-			of_node_put(node);
-			return edev;
-		}
-	}
-	mutex_unlock(&extcon_dev_list_lock);
+	edev = extcon_get_edev_by_of_node(node);
 	of_node_put(node);
 
-	return ERR_PTR(-EPROBE_DEFER);
+	return edev;
 }
+
 #else
+
+struct extcon_dev *extcon_get_edev_by_of_node(struct device_node *node)
+{
+	return ERR_PTR(-ENOSYS);
+}
+
 struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index)
 {
 	return ERR_PTR(-ENOSYS);
 }
+
 #endif /* CONFIG_OF */
+
+EXPORT_SYMBOL_GPL(extcon_get_edev_by_of_node);
 EXPORT_SYMBOL_GPL(extcon_get_edev_by_phandle);
 
 /**
diff --git a/include/linux/extcon.h b/include/linux/extcon.h
index 6d94e82c8ad9..b47e0c7f01fe 100644
--- a/include/linux/extcon.h
+++ b/include/linux/extcon.h
@@ -230,6 +230,7 @@ extern void devm_extcon_unregister_notifier_all(struct device *dev,
  * Following APIs get the extcon_dev from devicetree or by through extcon name.
  */
 extern struct extcon_dev *extcon_get_extcon_dev(const char *extcon_name);
+extern struct extcon_dev *extcon_get_edev_by_of_node(struct device_node *node);
 extern struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev,
 						     int index);
 
@@ -283,6 +284,11 @@ static inline struct extcon_dev *extcon_get_extcon_dev(const char *extcon_name)
 	return ERR_PTR(-ENODEV);
 }
 
+static inline struct extcon_dev *extcon_get_edev_by_of_node(struct device_node *node)
+{
+	return ERR_PTR(-ENODEV);
+}
+
 static inline struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev,
 				int index)
 {
-- 
2.16.1

Re: [PATCH v4 5/6] extcon: add possibility to get extcon device by OF node

[Andy Shevchenko]

On Wed, Feb 21, 2018 at 10:55 AM, Andrzej Hajda <a.hajda@samsung.com> wrote:
> Since extcon property is not allowed in DT, extcon subsystem requires
> another way to get extcon device. Lets try the simplest approach - get
> edev by of_node.

> +/*
> + * extcon_get_edev_by_of_node - Get the extcon device from devicetree.
> + * @node       : OF node identyfying edev
> + *
> + * Return the pointer of extcon device if success or ERR_PTR(err) if fail.
> + */
> +struct extcon_dev *extcon_get_edev_by_of_node(struct device_node *node)

First of all, the all other similar cases use "_by_node" in the name.
Second, it's not _get_, it's _find_.

> +{
> +       struct extcon_dev *edev;
> +
> +       mutex_lock(&extcon_dev_list_lock);
> +       list_for_each_entry(edev, &extcon_dev_list, entry)
> +               if (edev->dev.parent && edev->dev.parent->of_node == node)
> +                       goto out;
> +       edev = ERR_PTR(-EPROBE_DEFER);
> +out:
> +       mutex_unlock(&extcon_dev_list_lock);
> +
> +       return edev;

Can't it be done using bus_find_device()?

> +}

See good example in i2c-core-of.c

of_find_i2c_adapter_by_node()
of_get_i2c_adapter_by_node()

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v4 5/6] extcon: add possibility to get extcon device by OF node

[Andrzej Hajda]

On 21.02.2018 15:27, Andy Shevchenko wrote:
> On Wed, Feb 21, 2018 at 10:55 AM, Andrzej Hajda <a.hajda@samsung.com> wrote:
>> Since extcon property is not allowed in DT, extcon subsystem requires
>> another way to get extcon device. Lets try the simplest approach - get
>> edev by of_node.
>> +/*
>> + * extcon_get_edev_by_of_node - Get the extcon device from devicetree.
>> + * @node       : OF node identyfying edev
>> + *
>> + * Return the pointer of extcon device if success or ERR_PTR(err) if fail.
>> + */
>> +struct extcon_dev *extcon_get_edev_by_of_node(struct device_node *node)
> First of all, the all other similar cases use "_by_node" in the name.

OK, looks better.

> Second, it's not _get_, it's _find_.

The patch splits exisiting extcon_get_edev_by_phandle function into two
functions, nothing more.
Thus it followed naming convention present in extcon framework. I can
switch it of course to _find_.

>
>> +{
>> +       struct extcon_dev *edev;
>> +
>> +       mutex_lock(&extcon_dev_list_lock);
>> +       list_for_each_entry(edev, &extcon_dev_list, entry)
>> +               if (edev->dev.parent && edev->dev.parent->of_node == node)
>> +                       goto out;
>> +       edev = ERR_PTR(-EPROBE_DEFER);
>> +out:
>> +       mutex_unlock(&extcon_dev_list_lock);
>> +
>> +       return edev;
> Can't it be done using bus_find_device()?

There is no special extcon bus, so I am not sure. Anyway if it can, it
should be done probably in another patch.

Regards
Andrzej

[PATCH v4 6/6] drm/bridge/sii8620: use micro-USB cable detection logic to detect MHL

[Andrzej Hajda]

From: Maciej Purski <m.purski@samsung.com>

Currently MHL chip must be turned on permanently to detect MHL cable. It
duplicates micro-USB controller's (MUIC) functionality and consumes
unnecessary power. Lets use extcon attached to MUIC to enable MHL chip
only if it detects MHL cable.

Signed-off-by: Maciej Purski <m.purski@samsung.com>
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
---
This is rework of the patch by Maciej with following changes:
- use micro-USB port bindings to get extcon, instead of extcon property,
- fixed remove sequence,
- fixed extcon get state logic.

Code finding extcon node is hacky IMO, I guess ultimately it should be done
via some framework (maybe even extcon), or at least via helper, I hope it
can stay as is until the proper solution will be merged.

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
---
 drivers/gpu/drm/bridge/sil-sii8620.c | 97 ++++++++++++++++++++++++++++++++++--
 1 file changed, 94 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/bridge/sil-sii8620.c b/drivers/gpu/drm/bridge/sil-sii8620.c
index 9e785b8e0ea2..565cc352ca81 100644
--- a/drivers/gpu/drm/bridge/sil-sii8620.c
+++ b/drivers/gpu/drm/bridge/sil-sii8620.c
@@ -17,6 +17,7 @@
 
 #include <linux/clk.h>
 #include <linux/delay.h>
+#include <linux/extcon.h>
 #include <linux/gpio/consumer.h>
 #include <linux/i2c.h>
 #include <linux/interrupt.h>
@@ -25,6 +26,7 @@
 #include <linux/list.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
+#include <linux/of_graph.h>
 #include <linux/regulator/consumer.h>
 #include <linux/slab.h>
 
@@ -81,6 +83,10 @@ struct sii8620 {
 	struct edid *edid;
 	unsigned int gen2_write_burst:1;
 	enum sii8620_mt_state mt_state;
+	struct extcon_dev *extcon;
+	struct notifier_block extcon_nb;
+	struct work_struct extcon_wq;
+	int cable_state;
 	struct list_head mt_queue;
 	struct {
 		int r_size;
@@ -2175,6 +2181,77 @@ static void sii8620_init_rcp_input_dev(struct sii8620 *ctx)
 	ctx->rc_dev = rc_dev;
 }
 
+static void sii8620_cable_out(struct sii8620 *ctx)
+{
+	disable_irq(to_i2c_client(ctx->dev)->irq);
+	sii8620_hw_off(ctx);
+}
+
+static void sii8620_extcon_work(struct work_struct *work)
+{
+	struct sii8620 *ctx =
+		container_of(work, struct sii8620, extcon_wq);
+	int state = extcon_get_state(ctx->extcon, EXTCON_DISP_MHL);
+
+	if (state == ctx->cable_state)
+		return;
+
+	ctx->cable_state = state;
+
+	if (state > 0)
+		sii8620_cable_in(ctx);
+	else
+		sii8620_cable_out(ctx);
+}
+
+static int sii8620_extcon_notifier(struct notifier_block *self,
+			unsigned long event, void *ptr)
+{
+	struct sii8620 *ctx =
+		container_of(self, struct sii8620, extcon_nb);
+
+	schedule_work(&ctx->extcon_wq);
+
+	return NOTIFY_DONE;
+}
+
+static int sii8620_extcon_init(struct sii8620 *ctx)
+{
+	struct extcon_dev *edev;
+	struct device_node *musb, *muic;
+	int ret;
+
+	/* get micro-USB connector node */
+	musb = of_graph_get_remote_node(ctx->dev->of_node, 1, -1);
+	/* next get micro-USB Interface Controller node */
+	muic = of_get_next_parent(musb);
+
+	if (!muic) {
+		dev_info(ctx->dev, "no extcon found, switching to 'always on' mode\n");
+		return 0;
+	}
+
+	edev = extcon_get_edev_by_of_node(muic);
+	of_node_put(muic);
+	if (IS_ERR(edev)) {
+		if (PTR_ERR(edev) == -EPROBE_DEFER)
+			return -EPROBE_DEFER;
+		dev_err(ctx->dev, "Invalid or missing extcon\n");
+		return PTR_ERR(edev);
+	}
+
+	ctx->extcon = edev;
+	ctx->extcon_nb.notifier_call = sii8620_extcon_notifier;
+	INIT_WORK(&ctx->extcon_wq, sii8620_extcon_work);
+	ret = extcon_register_notifier(edev, EXTCON_DISP_MHL, &ctx->extcon_nb);
+	if (ret) {
+		dev_err(ctx->dev, "failed to register notifier for MHL\n");
+		return ret;
+	}
+
+	return 0;
+}
+
 static inline struct sii8620 *bridge_to_sii8620(struct drm_bridge *bridge)
 {
 	return container_of(bridge, struct sii8620, bridge);
@@ -2307,13 +2384,20 @@ static int sii8620_probe(struct i2c_client *client,
 	if (ret)
 		return ret;
 
+	ret = sii8620_extcon_init(ctx);
+	if (ret < 0) {
+		dev_err(ctx->dev, "failed to initialize EXTCON\n");
+		return ret;
+	}
+
 	i2c_set_clientdata(client, ctx);
 
 	ctx->bridge.funcs = &sii8620_bridge_funcs;
 	ctx->bridge.of_node = dev->of_node;
 	drm_bridge_add(&ctx->bridge);
 
-	sii8620_cable_in(ctx);
+	if (!ctx->extcon)
+		sii8620_cable_in(ctx);
 
 	return 0;
 }
@@ -2322,8 +2406,15 @@ static int sii8620_remove(struct i2c_client *client)
 {
 	struct sii8620 *ctx = i2c_get_clientdata(client);
 
-	disable_irq(to_i2c_client(ctx->dev)->irq);
-	sii8620_hw_off(ctx);
+	if (ctx->extcon) {
+		extcon_unregister_notifier(ctx->extcon, EXTCON_DISP_MHL,
+					   &ctx->extcon_nb);
+		flush_work(&ctx->extcon_wq);
+		if (ctx->cable_state > 0)
+			sii8620_cable_out(ctx);
+	} else {
+		sii8620_cable_out(ctx);
+	}
 	drm_bridge_remove(&ctx->bridge);
 
 	return 0;
-- 
2.16.1