[V1, 0/2] media: ov8856: DT bindings and sensor mode improvements

[V1, 0/2] media: ov8856: DT bindings and sensor mode improvements

[dongchun.zhu]

From: Dongchun Zhu <dongchun.zhu@mediatek.com>

Hello,

This series adds DT bindings and some more sensor modes for users to use.

From the latest ov8856 datasheet, it is proposed to adopt the resolution of 1632*1224 and 3264*2448,
together with Bayer Order of BGGR. Thus here we provide two more scenarios.

In addition, the hardware version of ov8856 is also distinguished from one OTP SRAM register R700F.
PLL register R3614 requires to be correspondingly updated.
For instance, 0x20 is suggested for 1B camera module.

It is emphasized that I2C still actives while device is to runtime suspended.
This makes ov8856_suspend function need to remove the operation of stoping streaming.

Finally, ARM and device tree matching were added as an alternative.

Dongchun Zhu (2):
  media: dt-bindings: media: i2c: Add bindings for OV8856
  media: i2c: Add more sensor mode for OV8856 camera sensor

 .../devicetree/bindings/media/i2c/ov8856.txt       |  41 ++
 MAINTAINERS                                        |   1 +
 drivers/media/i2c/ov8856.c                         | 624 ++++++++++++++++++++-
 3 files changed, 663 insertions(+), 3 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/media/i2c/ov8856.txt

-- 
2.9.2

[V1, 1/2] media: dt-bindings: media: i2c: Add bindings for ov8856

[dongchun.zhu]

From: Dongchun Zhu <dongchun.zhu@mediatek.com>

Add device tree binding documentation for the ov8856 camera sensor.

Signed-off-by: Dongchun Zhu <dongchun.zhu@mediatek.com>
---
 .../devicetree/bindings/media/i2c/ov8856.txt       | 41 ++++++++++++++++++++++
 MAINTAINERS                                        |  1 +
 2 files changed, 42 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/media/i2c/ov8856.txt

diff --git a/Documentation/devicetree/bindings/media/i2c/ov8856.txt b/Documentation/devicetree/bindings/media/i2c/ov8856.txt
new file mode 100644
index 0000000..96b10e0
--- /dev/null
+++ b/Documentation/devicetree/bindings/media/i2c/ov8856.txt
@@ -0,0 +1,41 @@
+* Omnivision OV8856 MIPI CSI-2 sensor
+
+Required Properties:
+- compatible: shall be "ovti,ov8856"
+- clocks: reference to the xvclk input clock
+- clock-names: shall be "xvclk"
+- avdd-supply: Analog voltage supply, 2.8 volts
+- dovdd-supply: Digital I/O voltage supply, 1.8 volts
+- dvdd-supply: Digital core voltage supply, 1.2 volts
+- reset-gpios: Low active reset gpio
+
+The device node shall contain one 'port' child node with an
+'endpoint' subnode for its digital output video port,
+in accordance with the video interface bindings defined in
+Documentation/devicetree/bindings/media/video-interfaces.txt.
+The endpoint optional property 'data-lanes' shall be "<0 1 3 4>".
+
+Example:
+&i2c7 {
+	ov8856: camera-sensor@10 {
+		compatible = "ovti,ov8856";
+		reg = <0x10>;
+		pinctrl-names = "default";
+		pinctrl-0 = <&clk_24m_cam>;
+
+		clocks = <&cru SCLK_TESTCLKOUT1>;
+		clock-names = "xvclk";
+
+		avdd-supply = <&mt6358_vcama2_reg>;
+		dvdd-supply = <&mt6358_vcamd_reg>;
+		dovdd-supply = <&mt6358_vcamio_reg>;
+		reset-gpios = <&gpio2 3 GPIO_ACTIVE_LOW>;
+
+		port {
+			wcam_out: endpoint {
+				remote-endpoint = <&mipi_in_wcam>;
+				data-lanes = <0 1 3 4>;
+			};
+		};
+	};
+};
diff --git a/MAINTAINERS b/MAINTAINERS
index 783569e..7746c6b 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11889,6 +11889,7 @@ L:	linux-media@vger.kernel.org
 T:	git git://linuxtv.org/media_tree.git
 S:	Maintained
 F:	drivers/media/i2c/ov8856.c
+F:	Documentation/devicetree/bindings/media/i2c/ov8856.txt
 
 OMNIVISION OV9650 SENSOR DRIVER
 M:	Sakari Ailus <sakari.ailus@linux.intel.com>
-- 
2.9.2

Re: [V1, 1/2] media: dt-bindings: media: i2c: Add bindings for ov8856

[Sakari Ailus]

Hi Dongchun,

(Cc'ing Ben, too.)

On Thu, Aug 08, 2019 at 05:22:14PM +0800, dongchun.zhu@mediatek.com wrote:
> From: Dongchun Zhu <dongchun.zhu@mediatek.com>
> 
> Add device tree binding documentation for the ov8856 camera sensor.
> 
> Signed-off-by: Dongchun Zhu <dongchun.zhu@mediatek.com>
> ---
>  .../devicetree/bindings/media/i2c/ov8856.txt       | 41 ++++++++++++++++++++++
>  MAINTAINERS                                        |  1 +
>  2 files changed, 42 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/media/i2c/ov8856.txt
> 
> diff --git a/Documentation/devicetree/bindings/media/i2c/ov8856.txt b/Documentation/devicetree/bindings/media/i2c/ov8856.txt
> new file mode 100644
> index 0000000..96b10e0
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/media/i2c/ov8856.txt
> @@ -0,0 +1,41 @@
> +* Omnivision OV8856 MIPI CSI-2 sensor
> +
> +Required Properties:
> +- compatible: shall be "ovti,ov8856"
> +- clocks: reference to the xvclk input clock
> +- clock-names: shall be "xvclk"

Could you add "clock-frequency" property here, please, and specify the
upper and lower limits?

> +- avdd-supply: Analog voltage supply, 2.8 volts
> +- dovdd-supply: Digital I/O voltage supply, 1.8 volts
> +- dvdd-supply: Digital core voltage supply, 1.2 volts
> +- reset-gpios: Low active reset gpio
> +
> +The device node shall contain one 'port' child node with an
> +'endpoint' subnode for its digital output video port,
> +in accordance with the video interface bindings defined in
> +Documentation/devicetree/bindings/media/video-interfaces.txt.
> +The endpoint optional property 'data-lanes' shall be "<0 1 3 4>".

If you don't support lane reordering, then monotonically incrementing lane
numbers from 1 onwards are recommended.

Please also make the property mandatory.

> +
> +Example:
> +&i2c7 {
> +	ov8856: camera-sensor@10 {
> +		compatible = "ovti,ov8856";
> +		reg = <0x10>;
> +		pinctrl-names = "default";
> +		pinctrl-0 = <&clk_24m_cam>;
> +
> +		clocks = <&cru SCLK_TESTCLKOUT1>;
> +		clock-names = "xvclk";
> +
> +		avdd-supply = <&mt6358_vcama2_reg>;
> +		dvdd-supply = <&mt6358_vcamd_reg>;
> +		dovdd-supply = <&mt6358_vcamio_reg>;
> +		reset-gpios = <&gpio2 3 GPIO_ACTIVE_LOW>;
> +
> +		port {
> +			wcam_out: endpoint {
> +				remote-endpoint = <&mipi_in_wcam>;
> +				data-lanes = <0 1 3 4>;
> +			};
> +		};
> +	};
> +};
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 783569e..7746c6b 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -11889,6 +11889,7 @@ L:	linux-media@vger.kernel.org
>  T:	git git://linuxtv.org/media_tree.git
>  S:	Maintained
>  F:	drivers/media/i2c/ov8856.c
> +F:	Documentation/devicetree/bindings/media/i2c/ov8856.txt
>  
>  OMNIVISION OV9650 SENSOR DRIVER
>  M:	Sakari Ailus <sakari.ailus@linux.intel.com>

-- 
Regards,

Sakari Ailus
sakari.ailus@linux.intel.com

Re: [V1, 1/2] media: dt-bindings: media: i2c: Add bindings for ov8856

[Sakari Ailus]

On Thu, Aug 08, 2019 at 07:54:16PM +0300, Sakari Ailus wrote:
> Hi Dongchun,
> 
> (Cc'ing Ben, too.)
> 
> On Thu, Aug 08, 2019 at 05:22:14PM +0800, dongchun.zhu@mediatek.com wrote:
> > From: Dongchun Zhu <dongchun.zhu@mediatek.com>
> > 
> > Add device tree binding documentation for the ov8856 camera sensor.
> > 
> > Signed-off-by: Dongchun Zhu <dongchun.zhu@mediatek.com>
> > ---
> >  .../devicetree/bindings/media/i2c/ov8856.txt       | 41 ++++++++++++++++++++++
> >  MAINTAINERS                                        |  1 +
> >  2 files changed, 42 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/media/i2c/ov8856.txt
> > 
> > diff --git a/Documentation/devicetree/bindings/media/i2c/ov8856.txt b/Documentation/devicetree/bindings/media/i2c/ov8856.txt
> > new file mode 100644
> > index 0000000..96b10e0
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/media/i2c/ov8856.txt
> > @@ -0,0 +1,41 @@
> > +* Omnivision OV8856 MIPI CSI-2 sensor
> > +
> > +Required Properties:
> > +- compatible: shall be "ovti,ov8856"
> > +- clocks: reference to the xvclk input clock
> > +- clock-names: shall be "xvclk"
> 
> Could you add "clock-frequency" property here, please, and specify the
> upper and lower limits?

Can you also add the link-frequencies property, please?

-- 
Sakari Ailus
sakari.ailus@linux.intel.com

Re: [V1, 1/2] media: dt-bindings: media: i2c: Add bindings for ov8856

[Dongchun Zhu]

Hi Sakari,

On Thu, 2019-08-08 at 19:54 +0300, Sakari Ailus wrote:
> Hi Dongchun,
> 
> (Cc'ing Ben, too.)
> 
> On Thu, Aug 08, 2019 at 05:22:14PM +0800, dongchun.zhu@mediatek.com wrote:
> > From: Dongchun Zhu <dongchun.zhu@mediatek.com>
> > 
> > Add device tree binding documentation for the ov8856 camera sensor.
> > 
> > Signed-off-by: Dongchun Zhu <dongchun.zhu@mediatek.com>
> > ---
> >  .../devicetree/bindings/media/i2c/ov8856.txt       | 41 ++++++++++++++++++++++
> >  MAINTAINERS                                        |  1 +
> >  2 files changed, 42 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/media/i2c/ov8856.txt
> > 
> > diff --git a/Documentation/devicetree/bindings/media/i2c/ov8856.txt b/Documentation/devicetree/bindings/media/i2c/ov8856.txt
> > new file mode 100644
> > index 0000000..96b10e0
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/media/i2c/ov8856.txt
> > @@ -0,0 +1,41 @@
> > +* Omnivision OV8856 MIPI CSI-2 sensor
> > +
> > +Required Properties:
> > +- compatible: shall be "ovti,ov8856"
> > +- clocks: reference to the xvclk input clock
> > +- clock-names: shall be "xvclk"
> 
> Could you add "clock-frequency" property here, please, and specify the
> upper and lower limits?
> 

Sorry, this frequency of the external clock to the sensor and
link-frequencies would be added in DT in next release.

> > +- avdd-supply: Analog voltage supply, 2.8 volts
> > +- dovdd-supply: Digital I/O voltage supply, 1.8 volts
> > +- dvdd-supply: Digital core voltage supply, 1.2 volts
> > +- reset-gpios: Low active reset gpio
> > +
> > +The device node shall contain one 'port' child node with an
> > +'endpoint' subnode for its digital output video port,
> > +in accordance with the video interface bindings defined in
> > +Documentation/devicetree/bindings/media/video-interfaces.txt.
> > +The endpoint optional property 'data-lanes' shall be "<0 1 3 4>".
> 
> If you don't support lane reordering, then monotonically incrementing lane
> numbers from 1 onwards are recommended.
> 
> Please also make the property mandatory.
> 

data-lanes would be required property on endpoint in next release.

> > +
> > +Example:
> > +&i2c7 {
> > +	ov8856: camera-sensor@10 {
> > +		compatible = "ovti,ov8856";
> > +		reg = <0x10>;
> > +		pinctrl-names = "default";
> > +		pinctrl-0 = <&clk_24m_cam>;
> > +
> > +		clocks = <&cru SCLK_TESTCLKOUT1>;
> > +		clock-names = "xvclk";
> > +
> > +		avdd-supply = <&mt6358_vcama2_reg>;
> > +		dvdd-supply = <&mt6358_vcamd_reg>;
> > +		dovdd-supply = <&mt6358_vcamio_reg>;
> > +		reset-gpios = <&gpio2 3 GPIO_ACTIVE_LOW>;
> > +
> > +		port {
> > +			wcam_out: endpoint {
> > +				remote-endpoint = <&mipi_in_wcam>;
> > +				data-lanes = <0 1 3 4>;
> > +			};
> > +		};
> > +	};
> > +};
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index 783569e..7746c6b 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -11889,6 +11889,7 @@ L:	linux-media@vger.kernel.org
> >  T:	git git://linuxtv.org/media_tree.git
> >  S:	Maintained
> >  F:	drivers/media/i2c/ov8856.c
> > +F:	Documentation/devicetree/bindings/media/i2c/ov8856.txt
> >  
> >  OMNIVISION OV9650 SENSOR DRIVER
> >  M:	Sakari Ailus <sakari.ailus@linux.intel.com>
> 

[V1, 2/2] media: i2c: Add more sensor mode for ov8856 camera sensor

[dongchun.zhu]

From: Dongchun Zhu <dongchun.zhu@mediatek.com>

This patch mainly adds two more sensor modes for OV8856 image sensor.
The OV8856 driver currently supports output format: 10-bit Raw,
the resolution of 1632*1224 and 3264*2448, and the bayer order of BGGR.
The hardware version also differs in some OTP regiser,
as well as PLL register setting.

Signed-off-by: Dongchun Zhu <dongchun.zhu@mediatek.com>
---
 drivers/media/i2c/ov8856.c | 624 ++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 621 insertions(+), 3 deletions(-)

diff --git a/drivers/media/i2c/ov8856.c b/drivers/media/i2c/ov8856.c
index cd347d6..e0610b6 100644
--- a/drivers/media/i2c/ov8856.c
+++ b/drivers/media/i2c/ov8856.c
@@ -1,12 +1,15 @@
 // SPDX-License-Identifier: GPL-2.0
 // Copyright (c) 2019 Intel Corporation.
 
+#include <linux/clk.h>
 #include <asm/unaligned.h>
 #include <linux/acpi.h>
 #include <linux/delay.h>
+#include <linux/gpio/consumer.h>
 #include <linux/i2c.h>
 #include <linux/module.h>
 #include <linux/pm_runtime.h>
+#include <linux/regulator/consumer.h>
 #include <media/v4l2-ctrls.h>
 #include <media/v4l2-device.h>
 #include <media/v4l2-fwnode.h>
@@ -19,6 +22,7 @@
 #define OV8856_LINK_FREQ_180MHZ		180000000ULL
 #define OV8856_SCLK			144000000ULL
 #define OV8856_MCLK			19200000
+#define OV8856_XVCLK_FREQ		24000000
 #define OV8856_DATA_LANES		4
 #define OV8856_RGB_DEPTH		10
 
@@ -29,6 +33,18 @@
 #define OV8856_MODE_STANDBY		0x00
 #define OV8856_MODE_STREAMING		0x01
 
+/* define 1B module */
+#define OV8856_1B_MODULE		0x02
+
+/* otp sram register */
+#define OV8856_OTP_REG			0x700f
+#define OV8856_OTP_REG_ONE		0x3d84
+#define OV8856_OTP_REG_TWO		0x3d81
+
+/* clock register */
+#define OV8856_CLK_REG			0x3614
+#define OV8856_CLK_REG_1B_VAL		0x20
+
 /* vertical-timings from sensor */
 #define OV8856_REG_VTS			0x380e
 #define OV8856_VTS_MAX			0x7fff
@@ -64,6 +80,14 @@
 
 #define to_ov8856(_sd)			container_of(_sd, struct ov8856, sd)
 
+static const char * const ov8856_supply_names[] = {
+	"dovdd",	/* Digital I/O power */
+	"avdd",		/* Analog power */
+	"dvdd",		/* Digital core power */
+};
+
+#define OV8856_NUM_SUPPLIES ARRAY_SIZE(ov8856_supply_names)
+
 enum {
 	OV8856_LINK_FREQ_720MBPS,
 	OV8856_LINK_FREQ_360MBPS,
@@ -316,6 +340,208 @@ static const struct ov8856_reg mode_3280x2464_regs[] = {
 	{0x5e00, 0x00}
 };
 
+static const struct ov8856_reg mode_3264x2448_regs[] = {
+	{0x0103, 0x01},
+	{0x0302, 0x3c},
+	{0x0303, 0x01},
+	{0x031e, 0x0c},
+	{0x3000, 0x00},
+	{0x300e, 0x00},
+	{0x3010, 0x00},
+	{0x3015, 0x84},
+	{0x3018, 0x72},
+	{0x3021, 0x23},
+	{0x3033, 0x24},
+	{0x3500, 0x00},
+	{0x3501, 0x9a},
+	{0x3502, 0x20},
+	{0x3503, 0x08},
+	{0x3505, 0x83},
+	{0x3508, 0x01},
+	{0x3509, 0x80},
+	{0x350c, 0x00},
+	{0x350d, 0x80},
+	{0x350e, 0x04},
+	{0x350f, 0x00},
+	{0x3510, 0x00},
+	{0x3511, 0x02},
+	{0x3512, 0x00},
+	{0x3600, 0x72},
+	{0x3601, 0x40},
+	{0x3602, 0x30},
+	{0x3610, 0xc5},
+	{0x3611, 0x58},
+	{0x3612, 0x5c},
+	{0x3613, 0xca},
+	{0x3614, 0x60},
+	{0x3628, 0xff},
+	{0x3629, 0xff},
+	{0x362a, 0xff},
+	{0x3633, 0x10},
+	{0x3634, 0x10},
+	{0x3635, 0x10},
+	{0x3636, 0x10},
+	{0x3663, 0x08},
+	{0x3669, 0x34},
+	{0x366d, 0x00},
+	{0x366e, 0x10},
+	{0x3706, 0x86},
+	{0x370b, 0x7e},
+	{0x3714, 0x23},
+	{0x3730, 0x12},
+	{0x3733, 0x10},
+	{0x3764, 0x00},
+	{0x3765, 0x00},
+	{0x3769, 0x62},
+	{0x376a, 0x2a},
+	{0x376b, 0x30},
+	{0x3780, 0x00},
+	{0x3781, 0x24},
+	{0x3782, 0x00},
+	{0x3783, 0x23},
+	{0x3798, 0x2f},
+	{0x37a1, 0x60},
+	{0x37a8, 0x6a},
+	{0x37ab, 0x3f},
+	{0x37c2, 0x04},
+	{0x37c3, 0xf1},
+	{0x37c9, 0x80},
+	{0x37cb, 0x16},
+	{0x37cc, 0x16},
+	{0x37cd, 0x16},
+	{0x37ce, 0x16},
+	{0x3800, 0x00},
+	{0x3801, 0x00},
+	{0x3802, 0x00},
+	{0x3803, 0x0c},
+	{0x3804, 0x0c},
+	{0x3805, 0xdf},
+	{0x3806, 0x09},
+	{0x3807, 0xa3},
+	{0x3808, 0x0c},
+	{0x3809, 0xc0},
+	{0x380a, 0x09},
+	{0x380b, 0x90},
+	{0x380c, 0x07},
+	{0x380d, 0x8c},
+	{0x380e, 0x09},
+	{0x380f, 0xb2},
+	{0x3810, 0x00},
+	{0x3811, 0x04},
+	{0x3812, 0x00},
+	{0x3813, 0x02},
+	{0x3814, 0x01},
+	{0x3815, 0x01},
+	{0x3816, 0x00},
+	{0x3817, 0x00},
+	{0x3818, 0x00},
+	{0x3819, 0x00},
+	{0x3820, 0x80},
+	{0x3821, 0x46},
+	{0x382a, 0x01},
+	{0x382b, 0x01},
+	{0x3830, 0x06},
+	{0x3836, 0x02},
+	{0x3862, 0x04},
+	{0x3863, 0x08},
+	{0x3cc0, 0x33},
+	{0x3d85, 0x17},
+	{0x3d8c, 0x73},
+	{0x3d8d, 0xde},
+	{0x4001, 0xe0},
+	{0x4003, 0x40},
+	{0x4008, 0x00},
+	{0x4009, 0x0b},
+	{0x400a, 0x00},
+	{0x400b, 0x84},
+	{0x400f, 0x80},
+	{0x4010, 0xf0},
+	{0x4011, 0xff},
+	{0x4012, 0x02},
+	{0x4013, 0x01},
+	{0x4014, 0x01},
+	{0x4015, 0x01},
+	{0x4042, 0x00},
+	{0x4043, 0x80},
+	{0x4044, 0x00},
+	{0x4045, 0x80},
+	{0x4046, 0x00},
+	{0x4047, 0x80},
+	{0x4048, 0x00},
+	{0x4049, 0x80},
+	{0x4041, 0x03},
+	{0x404c, 0x20},
+	{0x404d, 0x00},
+	{0x404e, 0x20},
+	{0x4203, 0x80},
+	{0x4307, 0x30},
+	{0x4317, 0x00},
+	{0x4502, 0x50},
+	{0x4503, 0x08},
+	{0x4601, 0x80},
+	{0x4800, 0x44},
+	{0x4816, 0x53},
+	{0x481b, 0x50},
+	{0x481f, 0x27},
+	{0x4823, 0x3c},
+	{0x482b, 0x00},
+	{0x4831, 0x66},
+	{0x4837, 0x16},
+	{0x483c, 0x0f},
+	{0x484b, 0x05},
+	{0x5000, 0x77},
+	{0x5001, 0x0a},
+	{0x5003, 0xc8},
+	{0x5004, 0x04},
+	{0x5006, 0x00},
+	{0x5007, 0x00},
+	{0x502e, 0x03},
+	{0x5030, 0x41},
+	{0x5780, 0x14},
+	{0x5781, 0x0f},
+	{0x5782, 0x44},
+	{0x5783, 0x02},
+	{0x5784, 0x01},
+	{0x5785, 0x01},
+	{0x5786, 0x00},
+	{0x5787, 0x04},
+	{0x5788, 0x02},
+	{0x5789, 0x0f},
+	{0x578a, 0xfd},
+	{0x578b, 0xf5},
+	{0x578c, 0xf5},
+	{0x578d, 0x03},
+	{0x578e, 0x08},
+	{0x578f, 0x0c},
+	{0x5790, 0x08},
+	{0x5791, 0x04},
+	{0x5792, 0x00},
+	{0x5793, 0x52},
+	{0x5794, 0xa3},
+	{0x5795, 0x02},
+	{0x5796, 0x20},
+	{0x5797, 0x20},
+	{0x5798, 0xd5},
+	{0x5799, 0xd5},
+	{0x579a, 0x00},
+	{0x579b, 0x50},
+	{0x579c, 0x00},
+	{0x579d, 0x2c},
+	{0x579e, 0x0c},
+	{0x579f, 0x40},
+	{0x57a0, 0x09},
+	{0x57a1, 0x40},
+	{0x59f8, 0x3d},
+	{0x5a08, 0x02},
+	{0x5b00, 0x02},
+	{0x5b01, 0x10},
+	{0x5b02, 0x03},
+	{0x5b03, 0xcf},
+	{0x5b05, 0x6c},
+	{0x5e00, 0x00},
+	{0x5e10, 0xfc}
+};
+
 static const struct ov8856_reg mode_1640x1232_regs[] = {
 	{0x3000, 0x20},
 	{0x3003, 0x08},
@@ -506,6 +732,208 @@ static const struct ov8856_reg mode_1640x1232_regs[] = {
 	{0x5e00, 0x00}
 };
 
+static const struct ov8856_reg mode_1632x1224_regs[] = {
+	{0x0103, 0x01},
+	{0x0302, 0x3c},
+	{0x0303, 0x01},
+	{0x031e, 0x0c},
+	{0x3000, 0x00},
+	{0x300e, 0x00},
+	{0x3010, 0x00},
+	{0x3015, 0x84},
+	{0x3018, 0x72},
+	{0x3021, 0x23},
+	{0x3033, 0x24},
+	{0x3500, 0x00},
+	{0x3501, 0x4c},
+	{0x3502, 0xe0},
+	{0x3503, 0x08},
+	{0x3505, 0x83},
+	{0x3508, 0x01},
+	{0x3509, 0x80},
+	{0x350c, 0x00},
+	{0x350d, 0x80},
+	{0x350e, 0x04},
+	{0x350f, 0x00},
+	{0x3510, 0x00},
+	{0x3511, 0x02},
+	{0x3512, 0x00},
+	{0x3600, 0x72},
+	{0x3601, 0x40},
+	{0x3602, 0x30},
+	{0x3610, 0xc5},
+	{0x3611, 0x58},
+	{0x3612, 0x5c},
+	{0x3613, 0xca},
+	{0x3614, 0x60},
+	{0x3628, 0xff},
+	{0x3629, 0xff},
+	{0x362a, 0xff},
+	{0x3633, 0x10},
+	{0x3634, 0x10},
+	{0x3635, 0x10},
+	{0x3636, 0x10},
+	{0x3663, 0x08},
+	{0x3669, 0x34},
+	{0x366d, 0x00},
+	{0x366e, 0x08},
+	{0x3706, 0x86},
+	{0x370b, 0x7e},
+	{0x3714, 0x27},
+	{0x3730, 0x12},
+	{0x3733, 0x10},
+	{0x3764, 0x00},
+	{0x3765, 0x00},
+	{0x3769, 0x62},
+	{0x376a, 0x2a},
+	{0x376b, 0x30},
+	{0x3780, 0x00},
+	{0x3781, 0x24},
+	{0x3782, 0x00},
+	{0x3783, 0x23},
+	{0x3798, 0x2f},
+	{0x37a1, 0x60},
+	{0x37a8, 0x6a},
+	{0x37ab, 0x3f},
+	{0x37c2, 0x14},
+	{0x37c3, 0xf1},
+	{0x37c9, 0x80},
+	{0x37cb, 0x16},
+	{0x37cc, 0x16},
+	{0x37cd, 0x16},
+	{0x37ce, 0x16},
+	{0x3800, 0x00},
+	{0x3801, 0x00},
+	{0x3802, 0x00},
+	{0x3803, 0x0c},
+	{0x3804, 0x0c},
+	{0x3805, 0xdf},
+	{0x3806, 0x09},
+	{0x3807, 0xa3},
+	{0x3808, 0x06},
+	{0x3809, 0x60},
+	{0x380a, 0x04},
+	{0x380b, 0xc8},
+	{0x380c, 0x07},
+	{0x380d, 0x8c},
+	{0x380e, 0x09},
+	{0x380f, 0xb2},
+	{0x3810, 0x00},
+	{0x3811, 0x02},
+	{0x3812, 0x00},
+	{0x3813, 0x02},
+	{0x3814, 0x03},
+	{0x3815, 0x01},
+	{0x3816, 0x00},
+	{0x3817, 0x00},
+	{0x3818, 0x00},
+	{0x3819, 0x00},
+	{0x3820, 0x80},
+	{0x3821, 0x47},
+	{0x382a, 0x03},
+	{0x382b, 0x01},
+	{0x3830, 0x06},
+	{0x3836, 0x02},
+	{0x3862, 0x04},
+	{0x3863, 0x08},
+	{0x3cc0, 0x33},
+	{0x3d85, 0x17},
+	{0x3d8c, 0x73},
+	{0x3d8d, 0xde},
+	{0x4001, 0xe0},
+	{0x4003, 0x40},
+	{0x4008, 0x00},
+	{0x4009, 0x05},
+	{0x400a, 0x00},
+	{0x400b, 0x84},
+	{0x400f, 0x80},
+	{0x4010, 0xf0},
+	{0x4011, 0xff},
+	{0x4012, 0x02},
+	{0x4013, 0x01},
+	{0x4014, 0x01},
+	{0x4015, 0x01},
+	{0x4042, 0x00},
+	{0x4043, 0x80},
+	{0x4044, 0x00},
+	{0x4045, 0x80},
+	{0x4046, 0x00},
+	{0x4047, 0x80},
+	{0x4048, 0x00},
+	{0x4049, 0x80},
+	{0x4041, 0x03},
+	{0x404c, 0x20},
+	{0x404d, 0x00},
+	{0x404e, 0x20},
+	{0x4203, 0x80},
+	{0x4307, 0x30},
+	{0x4317, 0x00},
+	{0x4502, 0x50},
+	{0x4503, 0x08},
+	{0x4601, 0x80},
+	{0x4800, 0x44},
+	{0x4816, 0x53},
+	{0x481b, 0x50},
+	{0x481f, 0x27},
+	{0x4823, 0x3c},
+	{0x482b, 0x00},
+	{0x4831, 0x66},
+	{0x4837, 0x16},
+	{0x483c, 0x0f},
+	{0x484b, 0x05},
+	{0x5000, 0x77},
+	{0x5001, 0x0a},
+	{0x5003, 0xc8},
+	{0x5004, 0x04},
+	{0x5006, 0x00},
+	{0x5007, 0x00},
+	{0x502e, 0x03},
+	{0x5030, 0x41},
+	{0x5795, 0x00},
+	{0x5796, 0x10},
+	{0x5797, 0x10},
+	{0x5798, 0x73},
+	{0x5799, 0x73},
+	{0x579a, 0x00},
+	{0x579b, 0x28},
+	{0x579c, 0x00},
+	{0x579d, 0x16},
+	{0x579e, 0x06},
+	{0x579f, 0x20},
+	{0x57a0, 0x04},
+	{0x57a1, 0xa0},
+	{0x5780, 0x14},
+	{0x5781, 0x0f},
+	{0x5782, 0x44},
+	{0x5783, 0x02},
+	{0x5784, 0x01},
+	{0x5785, 0x01},
+	{0x5786, 0x00},
+	{0x5787, 0x04},
+	{0x5788, 0x02},
+	{0x5789, 0x0f},
+	{0x578a, 0xfd},
+	{0x578b, 0xf5},
+	{0x578c, 0xf5},
+	{0x578d, 0x03},
+	{0x578e, 0x08},
+	{0x578f, 0x0c},
+	{0x5790, 0x08},
+	{0x5791, 0x04},
+	{0x5792, 0x00},
+	{0x5793, 0x52},
+	{0x5794, 0xa3},
+	{0x59f8, 0x3d},
+	{0x5a08, 0x02},
+	{0x5b00, 0x02},
+	{0x5b01, 0x10},
+	{0x5b02, 0x03},
+	{0x5b03, 0xcf},
+	{0x5b05, 0x6c},
+	{0x5e00, 0x00},
+	{0x5e10, 0xfc}
+};
+
 static const char * const ov8856_test_pattern_menu[] = {
 	"Disabled",
 	"Standard Color Bar",
@@ -548,6 +976,18 @@ static const struct ov8856_mode supported_modes[] = {
 		.link_freq_index = OV8856_LINK_FREQ_720MBPS,
 	},
 	{
+		.width    = 3264,
+		.height   = 2448,
+		.hts      = 1932,
+		.vts_def  = 2482,
+		.vts_min  = 2482,
+		.reg_list = {
+			.num_of_regs = ARRAY_SIZE(mode_3264x2448_regs),
+			.regs = mode_3264x2448_regs,
+		},
+		.link_freq_index = OV8856_LINK_FREQ_720MBPS,
+	},
+	{
 		.width = 1640,
 		.height = 1232,
 		.hts = 3820,
@@ -558,6 +998,18 @@ static const struct ov8856_mode supported_modes[] = {
 			.regs = mode_1640x1232_regs,
 		},
 		.link_freq_index = OV8856_LINK_FREQ_360MBPS,
+	},
+	{
+		.width    = 1632,
+		.height   = 1224,
+		.hts      = 1932,
+		.vts_def  = 2482,
+		.vts_min  = 2482,
+		.reg_list = {
+			.num_of_regs = ARRAY_SIZE(mode_1632x1224_regs),
+			.regs = mode_1632x1224_regs,
+		},
+		.link_freq_index = OV8856_LINK_FREQ_360MBPS,
 	}
 };
 
@@ -566,6 +1018,10 @@ struct ov8856 {
 	struct media_pad pad;
 	struct v4l2_ctrl_handler ctrl_handler;
 
+	struct clk		*xvclk;
+	struct gpio_desc	*reset_gpio;
+	struct regulator_bulk_data supplies[OV8856_NUM_SUPPLIES];
+
 	/* V4L2 Controls */
 	struct v4l2_ctrl *link_freq;
 	struct v4l2_ctrl *pixel_rate;
@@ -576,6 +1032,9 @@ struct ov8856 {
 	/* Current mode */
 	const struct ov8856_mode *cur_mode;
 
+	/* module hardware version */
+	bool is_1B_module;
+
 	/* To serialize asynchronus callbacks */
 	struct mutex mutex;
 
@@ -696,6 +1155,24 @@ static int ov8856_test_pattern(struct ov8856 *ov8856, u32 pattern)
 				OV8856_REG_VALUE_08BIT, pattern);
 }
 
+static int ov8856_update_otp_reg(struct ov8856 *ov8856)
+{
+	int ret;
+
+	ret = ov8856_write_reg(ov8856, OV8856_REG_MODE_SELECT,
+			       OV8856_REG_VALUE_08BIT, OV8856_MODE_STREAMING);
+	if (ret)
+		return ret;
+
+	ret = ov8856_write_reg(ov8856, OV8856_OTP_REG_ONE,
+			       OV8856_REG_VALUE_08BIT, OV8856_MODE_STANDBY);
+	if (ret)
+		return ret;
+
+	return ov8856_write_reg(ov8856, OV8856_OTP_REG_TWO,
+				OV8856_REG_VALUE_08BIT, OV8856_MODE_STREAMING);
+}
+
 static int ov8856_set_ctrl(struct v4l2_ctrl *ctrl)
 {
 	struct ov8856 *ov8856 = container_of(ctrl->handler,
@@ -825,7 +1302,13 @@ static void ov8856_update_pad_format(const struct ov8856_mode *mode,
 {
 	fmt->width = mode->width;
 	fmt->height = mode->height;
-	fmt->code = MEDIA_BUS_FMT_SGRBG10_1X10;
+
+	/* Bayer Order is determined by image resolution */
+	if (fmt->width == 3264 || fmt->width == 1632)
+		fmt->code = MEDIA_BUS_FMT_SBGGR10_1X10;
+	else
+		fmt->code = MEDIA_BUS_FMT_SGRBG10_1X10;
+
 	fmt->field = V4L2_FIELD_NONE;
 }
 
@@ -850,6 +1333,17 @@ static int ov8856_start_streaming(struct ov8856 *ov8856)
 		return ret;
 	}
 
+	/* update R3614 for 1B module */
+	if (ov8856->is_1B_module) {
+		ret = ov8856_write_reg(ov8856, OV8856_CLK_REG,
+				       OV8856_REG_VALUE_08BIT,
+				       OV8856_CLK_REG_1B_VAL);
+		if (ret) {
+			dev_err(&client->dev, "failed to set R3614");
+			return ret;
+		}
+	}
+
 	ret = __v4l2_ctrl_handler_setup(ov8856->sd.ctrl_handler);
 	if (ret)
 		return ret;
@@ -882,6 +1376,8 @@ static int ov8856_set_stream(struct v4l2_subdev *sd, int enable)
 	if (ov8856->streaming == enable)
 		return 0;
 
+	dev_dbg(&client->dev, "hardware version: (%d)\n", ov8856->is_1B_module);
+
 	mutex_lock(&ov8856->mutex);
 	if (enable) {
 		ret = pm_runtime_get_sync(&client->dev);
@@ -908,6 +1404,54 @@ static int ov8856_set_stream(struct v4l2_subdev *sd, int enable)
 	return ret;
 }
 
+/* Calculate the delay in us by clock rate and clock cycles */
+static inline u32 ov8856_cal_delay(u32 cycles)
+{
+	return DIV_ROUND_UP(cycles, OV8856_XVCLK_FREQ / 1000 / 1000);
+}
+
+static int __ov8856_power_on(struct ov8856 *ov8856)
+{
+	int ret;
+	u32 delay_us;
+	struct i2c_client *client = v4l2_get_subdevdata(&ov8856->sd);
+
+	ret = clk_prepare_enable(ov8856->xvclk);
+	if (ret < 0) {
+		dev_err(&client->dev, "Failed to enable xvclk\n");
+		return ret;
+	}
+
+	gpiod_set_value_cansleep(ov8856->reset_gpio, 1);
+
+	ret = regulator_bulk_enable(OV8856_NUM_SUPPLIES, ov8856->supplies);
+	if (ret < 0) {
+		dev_err(&client->dev, "Failed to enable regulators\n");
+		goto disable_clk;
+	}
+
+	gpiod_set_value_cansleep(ov8856->reset_gpio, 0);
+
+	/* 8192 cycles prior to first SCCB transaction */
+	delay_us = ov8856_cal_delay(8192);
+	usleep_range(delay_us  * 2, delay_us * 4);
+
+	return 0;
+
+disable_clk:
+	clk_disable_unprepare(ov8856->xvclk);
+
+	return ret;
+}
+
+static void __ov8856_power_off(struct ov8856 *ov8856)
+{
+	clk_disable_unprepare(ov8856->xvclk);
+	gpiod_set_value_cansleep(ov8856->reset_gpio, 1);
+
+	regulator_bulk_disable(OV8856_NUM_SUPPLIES, ov8856->supplies);
+}
+
 static int __maybe_unused ov8856_suspend(struct device *dev)
 {
 	struct i2c_client *client = to_i2c_client(dev);
@@ -915,8 +1459,8 @@ static int __maybe_unused ov8856_suspend(struct device *dev)
 	struct ov8856 *ov8856 = to_ov8856(sd);
 
 	mutex_lock(&ov8856->mutex);
-	if (ov8856->streaming)
-		ov8856_stop_streaming(ov8856);
+
+	__ov8856_power_off(ov8856);
 
 	mutex_unlock(&ov8856->mutex);
 
@@ -1089,6 +1633,20 @@ static int ov8856_identify_module(struct ov8856 *ov8856)
 		return -ENXIO;
 	}
 
+	/* set R3614 to distinguish harward versions */
+	ret = ov8856_update_otp_reg(ov8856);
+	if (ret) {
+		dev_err(&client->dev, "failed to set otp register");
+		return ret;
+	}
+
+	ret = ov8856_read_reg(ov8856, OV8856_OTP_REG,
+			      OV8856_REG_VALUE_08BIT, &val);
+	if (ret)
+		return ret;
+
+	ov8856->is_1B_module = (val == OV8856_1B_MODULE) ? 1 : 0;
+
 	return 0;
 }
 
@@ -1164,11 +1722,27 @@ static int ov8856_remove(struct i2c_client *client)
 	media_entity_cleanup(&sd->entity);
 	v4l2_ctrl_handler_free(sd->ctrl_handler);
 	pm_runtime_disable(&client->dev);
+	if (!pm_runtime_status_suspended(&client->dev))
+		__ov8856_power_off(ov8856);
+	pm_runtime_set_suspended(&client->dev);
 	mutex_destroy(&ov8856->mutex);
 
 	return 0;
 }
 
+static int ov8856_configure_regulators(struct ov8856 *ov8856)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(&ov8856->sd);
+	int i;
+
+	for (i = 0; i < OV8856_NUM_SUPPLIES; i++)
+		ov8856->supplies[i].supply = ov8856_supply_names[i];
+
+	return devm_regulator_bulk_get(&client->dev,
+				       OV8856_NUM_SUPPLIES,
+				       ov8856->supplies);
+}
+
 static int ov8856_probe(struct i2c_client *client)
 {
 	struct ov8856 *ov8856;
@@ -1186,6 +1760,40 @@ static int ov8856_probe(struct i2c_client *client)
 		return -ENOMEM;
 
 	v4l2_i2c_subdev_init(&ov8856->sd, client, &ov8856_subdev_ops);
+
+	ov8856->xvclk = devm_clk_get(&client->dev, "xvclk");
+	if (IS_ERR(ov8856->xvclk)) {
+		dev_err(&client->dev, "Failed to get xvclk\n");
+		return -EINVAL;
+	}
+
+	ret = clk_set_rate(ov8856->xvclk, OV8856_XVCLK_FREQ);
+	if (ret < 0) {
+		dev_err(&client->dev, "Failed to set xvclk rate (24MHz)\n");
+		return ret;
+	}
+	if (clk_get_rate(ov8856->xvclk) != OV8856_XVCLK_FREQ)
+		dev_warn(&client->dev,
+			 "xvclk mismatched, modes are based on 24MHz\n");
+
+	ov8856->reset_gpio = devm_gpiod_get(&client->dev,
+					    "reset",
+					    GPIOD_OUT_LOW);
+	if (IS_ERR(ov8856->reset_gpio)) {
+		dev_err(&client->dev, "Failed to get reset-gpios\n");
+		return -EINVAL;
+	}
+
+	ret = ov8856_configure_regulators(ov8856);
+	if (ret) {
+		dev_err(&client->dev, "Failed to get power regulators\n");
+		return ret;
+	}
+
+	ret = __ov8856_power_on(ov8856);
+	if (ret)
+		goto probe_error_v4l2_ctrl_handler_free;
+
 	ret = ov8856_identify_module(ov8856);
 	if (ret) {
 		dev_err(&client->dev, "failed to find sensor: %d", ret);
@@ -1251,11 +1859,21 @@ static const struct acpi_device_id ov8856_acpi_ids[] = {
 MODULE_DEVICE_TABLE(acpi, ov8856_acpi_ids);
 #endif
 
+#if IS_ENABLED(CONFIG_OF)
+static const struct of_device_id ov8856_of_match[] = {
+	{ .compatible = "ovti,ov8856" },
+	{},
+};
+
+MODULE_DEVICE_TABLE(of, ov8856_of_match);
+#endif
+
 static struct i2c_driver ov8856_i2c_driver = {
 	.driver = {
 		.name = "ov8856",
 		.pm = &ov8856_pm_ops,
 		.acpi_match_table = ACPI_PTR(ov8856_acpi_ids),
+		.of_match_table = of_match_ptr(ov8856_of_match),
 	},
 	.probe_new = ov8856_probe,
 	.remove = ov8856_remove,
-- 
2.9.2

Re: [V1, 2/2] media: i2c: Add more sensor mode for ov8856 camera sensor

[Sakari Ailus]

Hi Dongchun,

Thanks for the patch.

On Thu, Aug 08, 2019 at 05:22:15PM +0800, dongchun.zhu@mediatek.com wrote:
> From: Dongchun Zhu <dongchun.zhu@mediatek.com>
> 
> This patch mainly adds two more sensor modes for OV8856 image sensor.
> The OV8856 driver currently supports output format: 10-bit Raw,
> the resolution of 1632*1224 and 3264*2448, and the bayer order of BGGR.
> The hardware version also differs in some OTP regiser,
> as well as PLL register setting.
> 
> Signed-off-by: Dongchun Zhu <dongchun.zhu@mediatek.com>
> ---
>  drivers/media/i2c/ov8856.c | 624 ++++++++++++++++++++++++++++++++++++++++++++-
>  1 file changed, 621 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/media/i2c/ov8856.c b/drivers/media/i2c/ov8856.c
> index cd347d6..e0610b6 100644
> --- a/drivers/media/i2c/ov8856.c
> +++ b/drivers/media/i2c/ov8856.c
> @@ -1,12 +1,15 @@
>  // SPDX-License-Identifier: GPL-2.0
>  // Copyright (c) 2019 Intel Corporation.
>  
> +#include <linux/clk.h>
>  #include <asm/unaligned.h>
>  #include <linux/acpi.h>
>  #include <linux/delay.h>
> +#include <linux/gpio/consumer.h>
>  #include <linux/i2c.h>
>  #include <linux/module.h>
>  #include <linux/pm_runtime.h>
> +#include <linux/regulator/consumer.h>
>  #include <media/v4l2-ctrls.h>
>  #include <media/v4l2-device.h>
>  #include <media/v4l2-fwnode.h>
> @@ -19,6 +22,7 @@
>  #define OV8856_LINK_FREQ_180MHZ		180000000ULL
>  #define OV8856_SCLK			144000000ULL
>  #define OV8856_MCLK			19200000
> +#define OV8856_XVCLK_FREQ		24000000

The driver currenctly uses, perhaps misleadingly, OV8856_MCLK for this
purpose. You could rename the existing MCLK as XVCLK.

This also means the driver needs to differentiate configurations for 24 and
19,2 MHz which it currently does not do. I think it may make sense to make
this a separate patch from the rest.

>  #define OV8856_DATA_LANES		4
>  #define OV8856_RGB_DEPTH		10
>  
> @@ -29,6 +33,18 @@
>  #define OV8856_MODE_STANDBY		0x00
>  #define OV8856_MODE_STREAMING		0x01
>  
> +/* define 1B module */
> +#define OV8856_1B_MODULE		0x02
> +
> +/* otp sram register */
> +#define OV8856_OTP_REG			0x700f
> +#define OV8856_OTP_REG_ONE		0x3d84
> +#define OV8856_OTP_REG_TWO		0x3d81
> +
> +/* clock register */
> +#define OV8856_CLK_REG			0x3614
> +#define OV8856_CLK_REG_1B_VAL		0x20
> +
>  /* vertical-timings from sensor */
>  #define OV8856_REG_VTS			0x380e
>  #define OV8856_VTS_MAX			0x7fff
> @@ -64,6 +80,14 @@
>  
>  #define to_ov8856(_sd)			container_of(_sd, struct ov8856, sd)
>  
> +static const char * const ov8856_supply_names[] = {
> +	"dovdd",	/* Digital I/O power */
> +	"avdd",		/* Analog power */
> +	"dvdd",		/* Digital core power */
> +};
> +
> +#define OV8856_NUM_SUPPLIES ARRAY_SIZE(ov8856_supply_names)
> +
>  enum {
>  	OV8856_LINK_FREQ_720MBPS,
>  	OV8856_LINK_FREQ_360MBPS,
> @@ -316,6 +340,208 @@ static const struct ov8856_reg mode_3280x2464_regs[] = {
>  	{0x5e00, 0x00}
>  };
>  
> +static const struct ov8856_reg mode_3264x2448_regs[] = {
> +	{0x0103, 0x01},
> +	{0x0302, 0x3c},
> +	{0x0303, 0x01},
> +	{0x031e, 0x0c},
> +	{0x3000, 0x00},
> +	{0x300e, 0x00},
> +	{0x3010, 0x00},
> +	{0x3015, 0x84},
> +	{0x3018, 0x72},
> +	{0x3021, 0x23},
> +	{0x3033, 0x24},
> +	{0x3500, 0x00},
> +	{0x3501, 0x9a},
> +	{0x3502, 0x20},
> +	{0x3503, 0x08},
> +	{0x3505, 0x83},
> +	{0x3508, 0x01},
> +	{0x3509, 0x80},
> +	{0x350c, 0x00},
> +	{0x350d, 0x80},
> +	{0x350e, 0x04},
> +	{0x350f, 0x00},
> +	{0x3510, 0x00},
> +	{0x3511, 0x02},
> +	{0x3512, 0x00},
> +	{0x3600, 0x72},
> +	{0x3601, 0x40},
> +	{0x3602, 0x30},
> +	{0x3610, 0xc5},
> +	{0x3611, 0x58},
> +	{0x3612, 0x5c},
> +	{0x3613, 0xca},
> +	{0x3614, 0x60},
> +	{0x3628, 0xff},
> +	{0x3629, 0xff},
> +	{0x362a, 0xff},
> +	{0x3633, 0x10},
> +	{0x3634, 0x10},
> +	{0x3635, 0x10},
> +	{0x3636, 0x10},
> +	{0x3663, 0x08},
> +	{0x3669, 0x34},
> +	{0x366d, 0x00},
> +	{0x366e, 0x10},
> +	{0x3706, 0x86},
> +	{0x370b, 0x7e},
> +	{0x3714, 0x23},
> +	{0x3730, 0x12},
> +	{0x3733, 0x10},
> +	{0x3764, 0x00},
> +	{0x3765, 0x00},
> +	{0x3769, 0x62},
> +	{0x376a, 0x2a},
> +	{0x376b, 0x30},
> +	{0x3780, 0x00},
> +	{0x3781, 0x24},
> +	{0x3782, 0x00},
> +	{0x3783, 0x23},
> +	{0x3798, 0x2f},
> +	{0x37a1, 0x60},
> +	{0x37a8, 0x6a},
> +	{0x37ab, 0x3f},
> +	{0x37c2, 0x04},
> +	{0x37c3, 0xf1},
> +	{0x37c9, 0x80},
> +	{0x37cb, 0x16},
> +	{0x37cc, 0x16},
> +	{0x37cd, 0x16},
> +	{0x37ce, 0x16},
> +	{0x3800, 0x00},
> +	{0x3801, 0x00},
> +	{0x3802, 0x00},
> +	{0x3803, 0x0c},
> +	{0x3804, 0x0c},
> +	{0x3805, 0xdf},
> +	{0x3806, 0x09},
> +	{0x3807, 0xa3},
> +	{0x3808, 0x0c},
> +	{0x3809, 0xc0},
> +	{0x380a, 0x09},
> +	{0x380b, 0x90},
> +	{0x380c, 0x07},
> +	{0x380d, 0x8c},
> +	{0x380e, 0x09},
> +	{0x380f, 0xb2},
> +	{0x3810, 0x00},
> +	{0x3811, 0x04},
> +	{0x3812, 0x00},
> +	{0x3813, 0x02},
> +	{0x3814, 0x01},
> +	{0x3815, 0x01},
> +	{0x3816, 0x00},
> +	{0x3817, 0x00},
> +	{0x3818, 0x00},
> +	{0x3819, 0x00},
> +	{0x3820, 0x80},
> +	{0x3821, 0x46},
> +	{0x382a, 0x01},
> +	{0x382b, 0x01},
> +	{0x3830, 0x06},
> +	{0x3836, 0x02},
> +	{0x3862, 0x04},
> +	{0x3863, 0x08},
> +	{0x3cc0, 0x33},
> +	{0x3d85, 0x17},
> +	{0x3d8c, 0x73},
> +	{0x3d8d, 0xde},
> +	{0x4001, 0xe0},
> +	{0x4003, 0x40},
> +	{0x4008, 0x00},
> +	{0x4009, 0x0b},
> +	{0x400a, 0x00},
> +	{0x400b, 0x84},
> +	{0x400f, 0x80},
> +	{0x4010, 0xf0},
> +	{0x4011, 0xff},
> +	{0x4012, 0x02},
> +	{0x4013, 0x01},
> +	{0x4014, 0x01},
> +	{0x4015, 0x01},
> +	{0x4042, 0x00},
> +	{0x4043, 0x80},
> +	{0x4044, 0x00},
> +	{0x4045, 0x80},
> +	{0x4046, 0x00},
> +	{0x4047, 0x80},
> +	{0x4048, 0x00},
> +	{0x4049, 0x80},
> +	{0x4041, 0x03},
> +	{0x404c, 0x20},
> +	{0x404d, 0x00},
> +	{0x404e, 0x20},
> +	{0x4203, 0x80},
> +	{0x4307, 0x30},
> +	{0x4317, 0x00},
> +	{0x4502, 0x50},
> +	{0x4503, 0x08},
> +	{0x4601, 0x80},
> +	{0x4800, 0x44},
> +	{0x4816, 0x53},
> +	{0x481b, 0x50},
> +	{0x481f, 0x27},
> +	{0x4823, 0x3c},
> +	{0x482b, 0x00},
> +	{0x4831, 0x66},
> +	{0x4837, 0x16},
> +	{0x483c, 0x0f},
> +	{0x484b, 0x05},
> +	{0x5000, 0x77},
> +	{0x5001, 0x0a},
> +	{0x5003, 0xc8},
> +	{0x5004, 0x04},
> +	{0x5006, 0x00},
> +	{0x5007, 0x00},
> +	{0x502e, 0x03},
> +	{0x5030, 0x41},
> +	{0x5780, 0x14},
> +	{0x5781, 0x0f},
> +	{0x5782, 0x44},
> +	{0x5783, 0x02},
> +	{0x5784, 0x01},
> +	{0x5785, 0x01},
> +	{0x5786, 0x00},
> +	{0x5787, 0x04},
> +	{0x5788, 0x02},
> +	{0x5789, 0x0f},
> +	{0x578a, 0xfd},
> +	{0x578b, 0xf5},
> +	{0x578c, 0xf5},
> +	{0x578d, 0x03},
> +	{0x578e, 0x08},
> +	{0x578f, 0x0c},
> +	{0x5790, 0x08},
> +	{0x5791, 0x04},
> +	{0x5792, 0x00},
> +	{0x5793, 0x52},
> +	{0x5794, 0xa3},
> +	{0x5795, 0x02},
> +	{0x5796, 0x20},
> +	{0x5797, 0x20},
> +	{0x5798, 0xd5},
> +	{0x5799, 0xd5},
> +	{0x579a, 0x00},
> +	{0x579b, 0x50},
> +	{0x579c, 0x00},
> +	{0x579d, 0x2c},
> +	{0x579e, 0x0c},
> +	{0x579f, 0x40},
> +	{0x57a0, 0x09},
> +	{0x57a1, 0x40},
> +	{0x59f8, 0x3d},
> +	{0x5a08, 0x02},
> +	{0x5b00, 0x02},
> +	{0x5b01, 0x10},
> +	{0x5b02, 0x03},
> +	{0x5b03, 0xcf},
> +	{0x5b05, 0x6c},
> +	{0x5e00, 0x00},
> +	{0x5e10, 0xfc}
> +};
> +
>  static const struct ov8856_reg mode_1640x1232_regs[] = {
>  	{0x3000, 0x20},
>  	{0x3003, 0x08},
> @@ -506,6 +732,208 @@ static const struct ov8856_reg mode_1640x1232_regs[] = {
>  	{0x5e00, 0x00}
>  };
>  
> +static const struct ov8856_reg mode_1632x1224_regs[] = {
> +	{0x0103, 0x01},
> +	{0x0302, 0x3c},
> +	{0x0303, 0x01},
> +	{0x031e, 0x0c},
> +	{0x3000, 0x00},
> +	{0x300e, 0x00},
> +	{0x3010, 0x00},
> +	{0x3015, 0x84},
> +	{0x3018, 0x72},
> +	{0x3021, 0x23},
> +	{0x3033, 0x24},
> +	{0x3500, 0x00},
> +	{0x3501, 0x4c},
> +	{0x3502, 0xe0},
> +	{0x3503, 0x08},
> +	{0x3505, 0x83},
> +	{0x3508, 0x01},
> +	{0x3509, 0x80},
> +	{0x350c, 0x00},
> +	{0x350d, 0x80},
> +	{0x350e, 0x04},
> +	{0x350f, 0x00},
> +	{0x3510, 0x00},
> +	{0x3511, 0x02},
> +	{0x3512, 0x00},
> +	{0x3600, 0x72},
> +	{0x3601, 0x40},
> +	{0x3602, 0x30},
> +	{0x3610, 0xc5},
> +	{0x3611, 0x58},
> +	{0x3612, 0x5c},
> +	{0x3613, 0xca},
> +	{0x3614, 0x60},
> +	{0x3628, 0xff},
> +	{0x3629, 0xff},
> +	{0x362a, 0xff},
> +	{0x3633, 0x10},
> +	{0x3634, 0x10},
> +	{0x3635, 0x10},
> +	{0x3636, 0x10},
> +	{0x3663, 0x08},
> +	{0x3669, 0x34},
> +	{0x366d, 0x00},
> +	{0x366e, 0x08},
> +	{0x3706, 0x86},
> +	{0x370b, 0x7e},
> +	{0x3714, 0x27},
> +	{0x3730, 0x12},
> +	{0x3733, 0x10},
> +	{0x3764, 0x00},
> +	{0x3765, 0x00},
> +	{0x3769, 0x62},
> +	{0x376a, 0x2a},
> +	{0x376b, 0x30},
> +	{0x3780, 0x00},
> +	{0x3781, 0x24},
> +	{0x3782, 0x00},
> +	{0x3783, 0x23},
> +	{0x3798, 0x2f},
> +	{0x37a1, 0x60},
> +	{0x37a8, 0x6a},
> +	{0x37ab, 0x3f},
> +	{0x37c2, 0x14},
> +	{0x37c3, 0xf1},
> +	{0x37c9, 0x80},
> +	{0x37cb, 0x16},
> +	{0x37cc, 0x16},
> +	{0x37cd, 0x16},
> +	{0x37ce, 0x16},
> +	{0x3800, 0x00},
> +	{0x3801, 0x00},
> +	{0x3802, 0x00},
> +	{0x3803, 0x0c},
> +	{0x3804, 0x0c},
> +	{0x3805, 0xdf},
> +	{0x3806, 0x09},
> +	{0x3807, 0xa3},
> +	{0x3808, 0x06},
> +	{0x3809, 0x60},
> +	{0x380a, 0x04},
> +	{0x380b, 0xc8},
> +	{0x380c, 0x07},
> +	{0x380d, 0x8c},
> +	{0x380e, 0x09},
> +	{0x380f, 0xb2},
> +	{0x3810, 0x00},
> +	{0x3811, 0x02},
> +	{0x3812, 0x00},
> +	{0x3813, 0x02},
> +	{0x3814, 0x03},
> +	{0x3815, 0x01},
> +	{0x3816, 0x00},
> +	{0x3817, 0x00},
> +	{0x3818, 0x00},
> +	{0x3819, 0x00},
> +	{0x3820, 0x80},
> +	{0x3821, 0x47},
> +	{0x382a, 0x03},
> +	{0x382b, 0x01},
> +	{0x3830, 0x06},
> +	{0x3836, 0x02},
> +	{0x3862, 0x04},
> +	{0x3863, 0x08},
> +	{0x3cc0, 0x33},
> +	{0x3d85, 0x17},
> +	{0x3d8c, 0x73},
> +	{0x3d8d, 0xde},
> +	{0x4001, 0xe0},
> +	{0x4003, 0x40},
> +	{0x4008, 0x00},
> +	{0x4009, 0x05},
> +	{0x400a, 0x00},
> +	{0x400b, 0x84},
> +	{0x400f, 0x80},
> +	{0x4010, 0xf0},
> +	{0x4011, 0xff},
> +	{0x4012, 0x02},
> +	{0x4013, 0x01},
> +	{0x4014, 0x01},
> +	{0x4015, 0x01},
> +	{0x4042, 0x00},
> +	{0x4043, 0x80},
> +	{0x4044, 0x00},
> +	{0x4045, 0x80},
> +	{0x4046, 0x00},
> +	{0x4047, 0x80},
> +	{0x4048, 0x00},
> +	{0x4049, 0x80},
> +	{0x4041, 0x03},
> +	{0x404c, 0x20},
> +	{0x404d, 0x00},
> +	{0x404e, 0x20},
> +	{0x4203, 0x80},
> +	{0x4307, 0x30},
> +	{0x4317, 0x00},
> +	{0x4502, 0x50},
> +	{0x4503, 0x08},
> +	{0x4601, 0x80},
> +	{0x4800, 0x44},
> +	{0x4816, 0x53},
> +	{0x481b, 0x50},
> +	{0x481f, 0x27},
> +	{0x4823, 0x3c},
> +	{0x482b, 0x00},
> +	{0x4831, 0x66},
> +	{0x4837, 0x16},
> +	{0x483c, 0x0f},
> +	{0x484b, 0x05},
> +	{0x5000, 0x77},
> +	{0x5001, 0x0a},
> +	{0x5003, 0xc8},
> +	{0x5004, 0x04},
> +	{0x5006, 0x00},
> +	{0x5007, 0x00},
> +	{0x502e, 0x03},
> +	{0x5030, 0x41},
> +	{0x5795, 0x00},
> +	{0x5796, 0x10},
> +	{0x5797, 0x10},
> +	{0x5798, 0x73},
> +	{0x5799, 0x73},
> +	{0x579a, 0x00},
> +	{0x579b, 0x28},
> +	{0x579c, 0x00},
> +	{0x579d, 0x16},
> +	{0x579e, 0x06},
> +	{0x579f, 0x20},
> +	{0x57a0, 0x04},
> +	{0x57a1, 0xa0},
> +	{0x5780, 0x14},
> +	{0x5781, 0x0f},
> +	{0x5782, 0x44},
> +	{0x5783, 0x02},
> +	{0x5784, 0x01},
> +	{0x5785, 0x01},
> +	{0x5786, 0x00},
> +	{0x5787, 0x04},
> +	{0x5788, 0x02},
> +	{0x5789, 0x0f},
> +	{0x578a, 0xfd},
> +	{0x578b, 0xf5},
> +	{0x578c, 0xf5},
> +	{0x578d, 0x03},
> +	{0x578e, 0x08},
> +	{0x578f, 0x0c},
> +	{0x5790, 0x08},
> +	{0x5791, 0x04},
> +	{0x5792, 0x00},
> +	{0x5793, 0x52},
> +	{0x5794, 0xa3},
> +	{0x59f8, 0x3d},
> +	{0x5a08, 0x02},
> +	{0x5b00, 0x02},
> +	{0x5b01, 0x10},
> +	{0x5b02, 0x03},
> +	{0x5b03, 0xcf},
> +	{0x5b05, 0x6c},
> +	{0x5e00, 0x00},
> +	{0x5e10, 0xfc}
> +};
> +
>  static const char * const ov8856_test_pattern_menu[] = {
>  	"Disabled",
>  	"Standard Color Bar",
> @@ -548,6 +976,18 @@ static const struct ov8856_mode supported_modes[] = {
>  		.link_freq_index = OV8856_LINK_FREQ_720MBPS,
>  	},
>  	{
> +		.width    = 3264,
> +		.height   = 2448,
> +		.hts      = 1932,
> +		.vts_def  = 2482,
> +		.vts_min  = 2482,
> +		.reg_list = {
> +			.num_of_regs = ARRAY_SIZE(mode_3264x2448_regs),
> +			.regs = mode_3264x2448_regs,
> +		},
> +		.link_freq_index = OV8856_LINK_FREQ_720MBPS,
> +	},
> +	{
>  		.width = 1640,
>  		.height = 1232,
>  		.hts = 3820,
> @@ -558,6 +998,18 @@ static const struct ov8856_mode supported_modes[] = {
>  			.regs = mode_1640x1232_regs,
>  		},
>  		.link_freq_index = OV8856_LINK_FREQ_360MBPS,
> +	},
> +	{
> +		.width    = 1632,
> +		.height   = 1224,
> +		.hts      = 1932,
> +		.vts_def  = 2482,
> +		.vts_min  = 2482,
> +		.reg_list = {
> +			.num_of_regs = ARRAY_SIZE(mode_1632x1224_regs),
> +			.regs = mode_1632x1224_regs,
> +		},
> +		.link_freq_index = OV8856_LINK_FREQ_360MBPS,
>  	}
>  };
>  
> @@ -566,6 +1018,10 @@ struct ov8856 {
>  	struct media_pad pad;
>  	struct v4l2_ctrl_handler ctrl_handler;
>  
> +	struct clk		*xvclk;
> +	struct gpio_desc	*reset_gpio;
> +	struct regulator_bulk_data supplies[OV8856_NUM_SUPPLIES];
> +
>  	/* V4L2 Controls */
>  	struct v4l2_ctrl *link_freq;
>  	struct v4l2_ctrl *pixel_rate;
> @@ -576,6 +1032,9 @@ struct ov8856 {
>  	/* Current mode */
>  	const struct ov8856_mode *cur_mode;
>  
> +	/* module hardware version */
> +	bool is_1B_module;

What other hardware versions are there, and what are the differences?

> +
>  	/* To serialize asynchronus callbacks */
>  	struct mutex mutex;
>  
> @@ -696,6 +1155,24 @@ static int ov8856_test_pattern(struct ov8856 *ov8856, u32 pattern)
>  				OV8856_REG_VALUE_08BIT, pattern);
>  }
>  
> +static int ov8856_update_otp_reg(struct ov8856 *ov8856)
> +{
> +	int ret;
> +
> +	ret = ov8856_write_reg(ov8856, OV8856_REG_MODE_SELECT,
> +			       OV8856_REG_VALUE_08BIT, OV8856_MODE_STREAMING);
> +	if (ret)
> +		return ret;
> +
> +	ret = ov8856_write_reg(ov8856, OV8856_OTP_REG_ONE,
> +			       OV8856_REG_VALUE_08BIT, OV8856_MODE_STANDBY);
> +	if (ret)
> +		return ret;
> +
> +	return ov8856_write_reg(ov8856, OV8856_OTP_REG_TWO,
> +				OV8856_REG_VALUE_08BIT, OV8856_MODE_STREAMING);
> +}

What does this do?

> +
>  static int ov8856_set_ctrl(struct v4l2_ctrl *ctrl)
>  {
>  	struct ov8856 *ov8856 = container_of(ctrl->handler,
> @@ -825,7 +1302,13 @@ static void ov8856_update_pad_format(const struct ov8856_mode *mode,
>  {
>  	fmt->width = mode->width;
>  	fmt->height = mode->height;
> -	fmt->code = MEDIA_BUS_FMT_SGRBG10_1X10;
> +
> +	/* Bayer Order is determined by image resolution */

Ouch. 

This rather looks like a side effect of vertical cropping. How about
either cropping one line above or below, to keep the same Bayer order?

The driver is based on register lists that heavily restricts the
possibilities of configuring the sensor. The alternative, should more
free-form configuration be enabled, would be to expose the cropping
capability to the user --- as well as binning.

> +	if (fmt->width == 3264 || fmt->width == 1632)
> +		fmt->code = MEDIA_BUS_FMT_SBGGR10_1X10;
> +	else
> +		fmt->code = MEDIA_BUS_FMT_SGRBG10_1X10;
> +
>  	fmt->field = V4L2_FIELD_NONE;
>  }
>  
> @@ -850,6 +1333,17 @@ static int ov8856_start_streaming(struct ov8856 *ov8856)
>  		return ret;
>  	}
>  
> +	/* update R3614 for 1B module */
> +	if (ov8856->is_1B_module) {
> +		ret = ov8856_write_reg(ov8856, OV8856_CLK_REG,
> +				       OV8856_REG_VALUE_08BIT,
> +				       OV8856_CLK_REG_1B_VAL);
> +		if (ret) {
> +			dev_err(&client->dev, "failed to set R3614");
> +			return ret;
> +		}
> +	}
> +
>  	ret = __v4l2_ctrl_handler_setup(ov8856->sd.ctrl_handler);
>  	if (ret)
>  		return ret;
> @@ -882,6 +1376,8 @@ static int ov8856_set_stream(struct v4l2_subdev *sd, int enable)
>  	if (ov8856->streaming == enable)
>  		return 0;
>  
> +	dev_dbg(&client->dev, "hardware version: (%d)\n", ov8856->is_1B_module);
> +
>  	mutex_lock(&ov8856->mutex);
>  	if (enable) {
>  		ret = pm_runtime_get_sync(&client->dev);
> @@ -908,6 +1404,54 @@ static int ov8856_set_stream(struct v4l2_subdev *sd, int enable)
>  	return ret;
>  }
>  
> +/* Calculate the delay in us by clock rate and clock cycles */
> +static inline u32 ov8856_cal_delay(u32 cycles)
> +{
> +	return DIV_ROUND_UP(cycles, OV8856_XVCLK_FREQ / 1000 / 1000);

The frequency is rounded down. As it is used to calculate a delay needed,
rounding up should be done for the frequency, too.

> +}
> +
> +static int __ov8856_power_on(struct ov8856 *ov8856)
> +{
> +	int ret;
> +	u32 delay_us;
> +	struct i2c_client *client = v4l2_get_subdevdata(&ov8856->sd);
> +
> +	ret = clk_prepare_enable(ov8856->xvclk);
> +	if (ret < 0) {
> +		dev_err(&client->dev, "Failed to enable xvclk\n");
> +		return ret;
> +	}
> +
> +	gpiod_set_value_cansleep(ov8856->reset_gpio, 1);
> +
> +	ret = regulator_bulk_enable(OV8856_NUM_SUPPLIES, ov8856->supplies);
> +	if (ret < 0) {
> +		dev_err(&client->dev, "Failed to enable regulators\n");
> +		goto disable_clk;
> +	}
> +
> +	gpiod_set_value_cansleep(ov8856->reset_gpio, 0);
> +
> +	/* 8192 cycles prior to first SCCB transaction */
> +	delay_us = ov8856_cal_delay(8192);
> +	usleep_range(delay_us  * 2, delay_us * 4);

Why multiply by 2?

Note that the driver still needs to work even if the resources aren't
visible to the software. That's the case e.g. on ACPI based systems.

> +
> +	return 0;
> +
> +disable_clk:
> +	clk_disable_unprepare(ov8856->xvclk);
> +
> +	return ret;
> +}
> +
> +static void __ov8856_power_off(struct ov8856 *ov8856)
> +{
> +	clk_disable_unprepare(ov8856->xvclk);
> +	gpiod_set_value_cansleep(ov8856->reset_gpio, 1);
> +
> +	regulator_bulk_disable(OV8856_NUM_SUPPLIES, ov8856->supplies);
> +}
> +
>  static int __maybe_unused ov8856_suspend(struct device *dev)
>  {
>  	struct i2c_client *client = to_i2c_client(dev);
> @@ -915,8 +1459,8 @@ static int __maybe_unused ov8856_suspend(struct device *dev)
>  	struct ov8856 *ov8856 = to_ov8856(sd);
>  
>  	mutex_lock(&ov8856->mutex);
> -	if (ov8856->streaming)
> -		ov8856_stop_streaming(ov8856);

This seems like an unrelated change.

> +
> +	__ov8856_power_off(ov8856);
>  
>  	mutex_unlock(&ov8856->mutex);
>  
> @@ -1089,6 +1633,20 @@ static int ov8856_identify_module(struct ov8856 *ov8856)
>  		return -ENXIO;
>  	}
>  
> +	/* set R3614 to distinguish harward versions */
> +	ret = ov8856_update_otp_reg(ov8856);
> +	if (ret) {
> +		dev_err(&client->dev, "failed to set otp register");
> +		return ret;
> +	}
> +
> +	ret = ov8856_read_reg(ov8856, OV8856_OTP_REG,
> +			      OV8856_REG_VALUE_08BIT, &val);
> +	if (ret)
> +		return ret;
> +
> +	ov8856->is_1B_module = (val == OV8856_1B_MODULE) ? 1 : 0;
> +
>  	return 0;
>  }
>  
> @@ -1164,11 +1722,27 @@ static int ov8856_remove(struct i2c_client *client)
>  	media_entity_cleanup(&sd->entity);
>  	v4l2_ctrl_handler_free(sd->ctrl_handler);
>  	pm_runtime_disable(&client->dev);
> +	if (!pm_runtime_status_suspended(&client->dev))
> +		__ov8856_power_off(ov8856);
> +	pm_runtime_set_suspended(&client->dev);
>  	mutex_destroy(&ov8856->mutex);
>  
>  	return 0;
>  }
>  
> +static int ov8856_configure_regulators(struct ov8856 *ov8856)
> +{
> +	struct i2c_client *client = v4l2_get_subdevdata(&ov8856->sd);
> +	int i;

unsigned int

> +
> +	for (i = 0; i < OV8856_NUM_SUPPLIES; i++)
> +		ov8856->supplies[i].supply = ov8856_supply_names[i];
> +
> +	return devm_regulator_bulk_get(&client->dev,
> +				       OV8856_NUM_SUPPLIES,
> +				       ov8856->supplies);

Remember to put the regulators, too.

> +}
> +
>  static int ov8856_probe(struct i2c_client *client)
>  {
>  	struct ov8856 *ov8856;
> @@ -1186,6 +1760,40 @@ static int ov8856_probe(struct i2c_client *client)
>  		return -ENOMEM;
>  
>  	v4l2_i2c_subdev_init(&ov8856->sd, client, &ov8856_subdev_ops);
> +
> +	ov8856->xvclk = devm_clk_get(&client->dev, "xvclk");
> +	if (IS_ERR(ov8856->xvclk)) {
> +		dev_err(&client->dev, "Failed to get xvclk\n");
> +		return -EINVAL;
> +	}
> +
> +	ret = clk_set_rate(ov8856->xvclk, OV8856_XVCLK_FREQ);
> +	if (ret < 0) {
> +		dev_err(&client->dev, "Failed to set xvclk rate (24MHz)\n");
> +		return ret;
> +	}
> +	if (clk_get_rate(ov8856->xvclk) != OV8856_XVCLK_FREQ)
> +		dev_warn(&client->dev,
> +			 "xvclk mismatched, modes are based on 24MHz\n");
> +
> +	ov8856->reset_gpio = devm_gpiod_get(&client->dev,
> +					    "reset",

Fits on the previous line.

> +					    GPIOD_OUT_LOW);
> +	if (IS_ERR(ov8856->reset_gpio)) {
> +		dev_err(&client->dev, "Failed to get reset-gpios\n");
> +		return -EINVAL;
> +	}
> +
> +	ret = ov8856_configure_regulators(ov8856);
> +	if (ret) {
> +		dev_err(&client->dev, "Failed to get power regulators\n");
> +		return ret;
> +	}
> +
> +	ret = __ov8856_power_on(ov8856);
> +	if (ret)
> +		goto probe_error_v4l2_ctrl_handler_free;
> +
>  	ret = ov8856_identify_module(ov8856);
>  	if (ret) {
>  		dev_err(&client->dev, "failed to find sensor: %d", ret);
> @@ -1251,11 +1859,21 @@ static const struct acpi_device_id ov8856_acpi_ids[] = {
>  MODULE_DEVICE_TABLE(acpi, ov8856_acpi_ids);
>  #endif
>  
> +#if IS_ENABLED(CONFIG_OF)
> +static const struct of_device_id ov8856_of_match[] = {
> +	{ .compatible = "ovti,ov8856" },
> +	{},
> +};
> +
> +MODULE_DEVICE_TABLE(of, ov8856_of_match);
> +#endif
> +
>  static struct i2c_driver ov8856_i2c_driver = {
>  	.driver = {
>  		.name = "ov8856",
>  		.pm = &ov8856_pm_ops,
>  		.acpi_match_table = ACPI_PTR(ov8856_acpi_ids),
> +		.of_match_table = of_match_ptr(ov8856_of_match),
>  	},
>  	.probe_new = ov8856_probe,
>  	.remove = ov8856_remove,

-- 
Regards,

Sakari Ailus

Re: [V1, 2/2] media: i2c: Add more sensor mode for ov8856 camera sensor

[Dongchun Zhu]

Hi Sakari,

On Thu, 2019-08-08 at 16:53 +0300, Sakari Ailus wrote:
> Hi Dongchun,
> 
> Thanks for the patch.
> 
> On Thu, Aug 08, 2019 at 05:22:15PM +0800, dongchun.zhu@mediatek.com wrote:
> > From: Dongchun Zhu <dongchun.zhu@mediatek.com>
> > 
> > This patch mainly adds two more sensor modes for OV8856 image sensor.
> > The OV8856 driver currently supports output format: 10-bit Raw,
> > the resolution of 1632*1224 and 3264*2448, and the bayer order of BGGR.
> > The hardware version also differs in some OTP regiser,
> > as well as PLL register setting.
> > 
> > Signed-off-by: Dongchun Zhu <dongchun.zhu@mediatek.com>
> > ---
> >  drivers/media/i2c/ov8856.c | 624 ++++++++++++++++++++++++++++++++++++++++++++-
> >  1 file changed, 621 insertions(+), 3 deletions(-)
> > 
> > diff --git a/drivers/media/i2c/ov8856.c b/drivers/media/i2c/ov8856.c
> > index cd347d6..e0610b6 100644
> > --- a/drivers/media/i2c/ov8856.c
> > +++ b/drivers/media/i2c/ov8856.c
> > @@ -1,12 +1,15 @@
> >  // SPDX-License-Identifier: GPL-2.0
> >  // Copyright (c) 2019 Intel Corporation.
> >  
> > +#include <linux/clk.h>
> >  #include <asm/unaligned.h>
> >  #include <linux/acpi.h>
> >  #include <linux/delay.h>
> > +#include <linux/gpio/consumer.h>
> >  #include <linux/i2c.h>
> >  #include <linux/module.h>
> >  #include <linux/pm_runtime.h>
> > +#include <linux/regulator/consumer.h>
> >  #include <media/v4l2-ctrls.h>
> >  #include <media/v4l2-device.h>
> >  #include <media/v4l2-fwnode.h>
> > @@ -19,6 +22,7 @@
> >  #define OV8856_LINK_FREQ_180MHZ		180000000ULL
> >  #define OV8856_SCLK			144000000ULL
> >  #define OV8856_MCLK			19200000
> > +#define OV8856_XVCLK_FREQ		24000000
> 
> The driver currenctly uses, perhaps misleadingly, OV8856_MCLK for this
> purpose. You could rename the existing MCLK as XVCLK.
> 

OV8856_MCLK would be replaced by OV8856_XVCLK in next release.

> This also means the driver needs to differentiate configurations for 24 and
> 19,2 MHz which it currently does not do. I think it may make sense to make
> this a separate patch from the rest.
> 

From datasheet, OV8856 could support input clock XVCLK range 6-27MHz.
But the typical frequency is 24MHz.
That's the value we now provide.
+Cc: Tomasz.
Tomasz, do you have any ideas about Sakari's propose?

> >  #define OV8856_DATA_LANES		4
> >  #define OV8856_RGB_DEPTH		10
> >  
> > @@ -29,6 +33,18 @@
> >  #define OV8856_MODE_STANDBY		0x00
> >  #define OV8856_MODE_STREAMING		0x01
> >  
> > +/* define 1B module */
> > +#define OV8856_1B_MODULE		0x02
> > +
> > +/* otp sram register */
> > +#define OV8856_OTP_REG			0x700f
> > +#define OV8856_OTP_REG_ONE		0x3d84
> > +#define OV8856_OTP_REG_TWO		0x3d81
> > +
> > +/* clock register */
> > +#define OV8856_CLK_REG			0x3614
> > +#define OV8856_CLK_REG_1B_VAL		0x20
> > +
> >  /* vertical-timings from sensor */
> >  #define OV8856_REG_VTS			0x380e
> >  #define OV8856_VTS_MAX			0x7fff
> > @@ -64,6 +80,14 @@
> >  
> >  #define to_ov8856(_sd)			container_of(_sd, struct ov8856, sd)
> >  
> > +static const char * const ov8856_supply_names[] = {
> > +	"dovdd",	/* Digital I/O power */
> > +	"avdd",		/* Analog power */
> > +	"dvdd",		/* Digital core power */
> > +};
> > +
> > +#define OV8856_NUM_SUPPLIES ARRAY_SIZE(ov8856_supply_names)
> > +
> >  enum {
> >  	OV8856_LINK_FREQ_720MBPS,
> >  	OV8856_LINK_FREQ_360MBPS,
> > @@ -316,6 +340,208 @@ static const struct ov8856_reg mode_3280x2464_regs[] = {
> >  	{0x5e00, 0x00}
> >  };
> >  
> > +static const struct ov8856_reg mode_3264x2448_regs[] = {
> > +	{0x0103, 0x01},
> > +	{0x0302, 0x3c},
> > +	{0x0303, 0x01},
> > +	{0x031e, 0x0c},
> > +	{0x3000, 0x00},
> > +	{0x300e, 0x00},
> > +	{0x3010, 0x00},
> > +	{0x3015, 0x84},
> > +	{0x3018, 0x72},
> > +	{0x3021, 0x23},
> > +	{0x3033, 0x24},
> > +	{0x3500, 0x00},
> > +	{0x3501, 0x9a},
> > +	{0x3502, 0x20},
> > +	{0x3503, 0x08},
> > +	{0x3505, 0x83},
> > +	{0x3508, 0x01},
> > +	{0x3509, 0x80},
> > +	{0x350c, 0x00},
> > +	{0x350d, 0x80},
> > +	{0x350e, 0x04},
> > +	{0x350f, 0x00},
> > +	{0x3510, 0x00},
> > +	{0x3511, 0x02},
> > +	{0x3512, 0x00},
> > +	{0x3600, 0x72},
> > +	{0x3601, 0x40},
> > +	{0x3602, 0x30},
> > +	{0x3610, 0xc5},
> > +	{0x3611, 0x58},
> > +	{0x3612, 0x5c},
> > +	{0x3613, 0xca},
> > +	{0x3614, 0x60},
> > +	{0x3628, 0xff},
> > +	{0x3629, 0xff},
> > +	{0x362a, 0xff},
> > +	{0x3633, 0x10},
> > +	{0x3634, 0x10},
> > +	{0x3635, 0x10},
> > +	{0x3636, 0x10},
> > +	{0x3663, 0x08},
> > +	{0x3669, 0x34},
> > +	{0x366d, 0x00},
> > +	{0x366e, 0x10},
> > +	{0x3706, 0x86},
> > +	{0x370b, 0x7e},
> > +	{0x3714, 0x23},
> > +	{0x3730, 0x12},
> > +	{0x3733, 0x10},
> > +	{0x3764, 0x00},
> > +	{0x3765, 0x00},
> > +	{0x3769, 0x62},
> > +	{0x376a, 0x2a},
> > +	{0x376b, 0x30},
> > +	{0x3780, 0x00},
> > +	{0x3781, 0x24},
> > +	{0x3782, 0x00},
> > +	{0x3783, 0x23},
> > +	{0x3798, 0x2f},
> > +	{0x37a1, 0x60},
> > +	{0x37a8, 0x6a},
> > +	{0x37ab, 0x3f},
> > +	{0x37c2, 0x04},
> > +	{0x37c3, 0xf1},
> > +	{0x37c9, 0x80},
> > +	{0x37cb, 0x16},
> > +	{0x37cc, 0x16},
> > +	{0x37cd, 0x16},
> > +	{0x37ce, 0x16},
> > +	{0x3800, 0x00},
> > +	{0x3801, 0x00},
> > +	{0x3802, 0x00},
> > +	{0x3803, 0x0c},
> > +	{0x3804, 0x0c},
> > +	{0x3805, 0xdf},
> > +	{0x3806, 0x09},
> > +	{0x3807, 0xa3},
> > +	{0x3808, 0x0c},
> > +	{0x3809, 0xc0},
> > +	{0x380a, 0x09},
> > +	{0x380b, 0x90},
> > +	{0x380c, 0x07},
> > +	{0x380d, 0x8c},
> > +	{0x380e, 0x09},
> > +	{0x380f, 0xb2},
> > +	{0x3810, 0x00},
> > +	{0x3811, 0x04},
> > +	{0x3812, 0x00},
> > +	{0x3813, 0x02},
> > +	{0x3814, 0x01},
> > +	{0x3815, 0x01},
> > +	{0x3816, 0x00},
> > +	{0x3817, 0x00},
> > +	{0x3818, 0x00},
> > +	{0x3819, 0x00},
> > +	{0x3820, 0x80},
> > +	{0x3821, 0x46},
> > +	{0x382a, 0x01},
> > +	{0x382b, 0x01},
> > +	{0x3830, 0x06},
> > +	{0x3836, 0x02},
> > +	{0x3862, 0x04},
> > +	{0x3863, 0x08},
> > +	{0x3cc0, 0x33},
> > +	{0x3d85, 0x17},
> > +	{0x3d8c, 0x73},
> > +	{0x3d8d, 0xde},
> > +	{0x4001, 0xe0},
> > +	{0x4003, 0x40},
> > +	{0x4008, 0x00},
> > +	{0x4009, 0x0b},
> > +	{0x400a, 0x00},
> > +	{0x400b, 0x84},
> > +	{0x400f, 0x80},
> > +	{0x4010, 0xf0},
> > +	{0x4011, 0xff},
> > +	{0x4012, 0x02},
> > +	{0x4013, 0x01},
> > +	{0x4014, 0x01},
> > +	{0x4015, 0x01},
> > +	{0x4042, 0x00},
> > +	{0x4043, 0x80},
> > +	{0x4044, 0x00},
> > +	{0x4045, 0x80},
> > +	{0x4046, 0x00},
> > +	{0x4047, 0x80},
> > +	{0x4048, 0x00},
> > +	{0x4049, 0x80},
> > +	{0x4041, 0x03},
> > +	{0x404c, 0x20},
> > +	{0x404d, 0x00},
> > +	{0x404e, 0x20},
> > +	{0x4203, 0x80},
> > +	{0x4307, 0x30},
> > +	{0x4317, 0x00},
> > +	{0x4502, 0x50},
> > +	{0x4503, 0x08},
> > +	{0x4601, 0x80},
> > +	{0x4800, 0x44},
> > +	{0x4816, 0x53},
> > +	{0x481b, 0x50},
> > +	{0x481f, 0x27},
> > +	{0x4823, 0x3c},
> > +	{0x482b, 0x00},
> > +	{0x4831, 0x66},
> > +	{0x4837, 0x16},
> > +	{0x483c, 0x0f},
> > +	{0x484b, 0x05},
> > +	{0x5000, 0x77},
> > +	{0x5001, 0x0a},
> > +	{0x5003, 0xc8},
> > +	{0x5004, 0x04},
> > +	{0x5006, 0x00},
> > +	{0x5007, 0x00},
> > +	{0x502e, 0x03},
> > +	{0x5030, 0x41},
> > +	{0x5780, 0x14},
> > +	{0x5781, 0x0f},
> > +	{0x5782, 0x44},
> > +	{0x5783, 0x02},
> > +	{0x5784, 0x01},
> > +	{0x5785, 0x01},
> > +	{0x5786, 0x00},
> > +	{0x5787, 0x04},
> > +	{0x5788, 0x02},
> > +	{0x5789, 0x0f},
> > +	{0x578a, 0xfd},
> > +	{0x578b, 0xf5},
> > +	{0x578c, 0xf5},
> > +	{0x578d, 0x03},
> > +	{0x578e, 0x08},
> > +	{0x578f, 0x0c},
> > +	{0x5790, 0x08},
> > +	{0x5791, 0x04},
> > +	{0x5792, 0x00},
> > +	{0x5793, 0x52},
> > +	{0x5794, 0xa3},
> > +	{0x5795, 0x02},
> > +	{0x5796, 0x20},
> > +	{0x5797, 0x20},
> > +	{0x5798, 0xd5},
> > +	{0x5799, 0xd5},
> > +	{0x579a, 0x00},
> > +	{0x579b, 0x50},
> > +	{0x579c, 0x00},
> > +	{0x579d, 0x2c},
> > +	{0x579e, 0x0c},
> > +	{0x579f, 0x40},
> > +	{0x57a0, 0x09},
> > +	{0x57a1, 0x40},
> > +	{0x59f8, 0x3d},
> > +	{0x5a08, 0x02},
> > +	{0x5b00, 0x02},
> > +	{0x5b01, 0x10},
> > +	{0x5b02, 0x03},
> > +	{0x5b03, 0xcf},
> > +	{0x5b05, 0x6c},
> > +	{0x5e00, 0x00},
> > +	{0x5e10, 0xfc}
> > +};
> > +
> >  static const struct ov8856_reg mode_1640x1232_regs[] = {
> >  	{0x3000, 0x20},
> >  	{0x3003, 0x08},
> > @@ -506,6 +732,208 @@ static const struct ov8856_reg mode_1640x1232_regs[] = {
> >  	{0x5e00, 0x00}
> >  };
> >  
> > +static const struct ov8856_reg mode_1632x1224_regs[] = {
> > +	{0x0103, 0x01},
> > +	{0x0302, 0x3c},
> > +	{0x0303, 0x01},
> > +	{0x031e, 0x0c},
> > +	{0x3000, 0x00},
> > +	{0x300e, 0x00},
> > +	{0x3010, 0x00},
> > +	{0x3015, 0x84},
> > +	{0x3018, 0x72},
> > +	{0x3021, 0x23},
> > +	{0x3033, 0x24},
> > +	{0x3500, 0x00},
> > +	{0x3501, 0x4c},
> > +	{0x3502, 0xe0},
> > +	{0x3503, 0x08},
> > +	{0x3505, 0x83},
> > +	{0x3508, 0x01},
> > +	{0x3509, 0x80},
> > +	{0x350c, 0x00},
> > +	{0x350d, 0x80},
> > +	{0x350e, 0x04},
> > +	{0x350f, 0x00},
> > +	{0x3510, 0x00},
> > +	{0x3511, 0x02},
> > +	{0x3512, 0x00},
> > +	{0x3600, 0x72},
> > +	{0x3601, 0x40},
> > +	{0x3602, 0x30},
> > +	{0x3610, 0xc5},
> > +	{0x3611, 0x58},
> > +	{0x3612, 0x5c},
> > +	{0x3613, 0xca},
> > +	{0x3614, 0x60},
> > +	{0x3628, 0xff},
> > +	{0x3629, 0xff},
> > +	{0x362a, 0xff},
> > +	{0x3633, 0x10},
> > +	{0x3634, 0x10},
> > +	{0x3635, 0x10},
> > +	{0x3636, 0x10},
> > +	{0x3663, 0x08},
> > +	{0x3669, 0x34},
> > +	{0x366d, 0x00},
> > +	{0x366e, 0x08},
> > +	{0x3706, 0x86},
> > +	{0x370b, 0x7e},
> > +	{0x3714, 0x27},
> > +	{0x3730, 0x12},
> > +	{0x3733, 0x10},
> > +	{0x3764, 0x00},
> > +	{0x3765, 0x00},
> > +	{0x3769, 0x62},
> > +	{0x376a, 0x2a},
> > +	{0x376b, 0x30},
> > +	{0x3780, 0x00},
> > +	{0x3781, 0x24},
> > +	{0x3782, 0x00},
> > +	{0x3783, 0x23},
> > +	{0x3798, 0x2f},
> > +	{0x37a1, 0x60},
> > +	{0x37a8, 0x6a},
> > +	{0x37ab, 0x3f},
> > +	{0x37c2, 0x14},
> > +	{0x37c3, 0xf1},
> > +	{0x37c9, 0x80},
> > +	{0x37cb, 0x16},
> > +	{0x37cc, 0x16},
> > +	{0x37cd, 0x16},
> > +	{0x37ce, 0x16},
> > +	{0x3800, 0x00},
> > +	{0x3801, 0x00},
> > +	{0x3802, 0x00},
> > +	{0x3803, 0x0c},
> > +	{0x3804, 0x0c},
> > +	{0x3805, 0xdf},
> > +	{0x3806, 0x09},
> > +	{0x3807, 0xa3},
> > +	{0x3808, 0x06},
> > +	{0x3809, 0x60},
> > +	{0x380a, 0x04},
> > +	{0x380b, 0xc8},
> > +	{0x380c, 0x07},
> > +	{0x380d, 0x8c},
> > +	{0x380e, 0x09},
> > +	{0x380f, 0xb2},
> > +	{0x3810, 0x00},
> > +	{0x3811, 0x02},
> > +	{0x3812, 0x00},
> > +	{0x3813, 0x02},
> > +	{0x3814, 0x03},
> > +	{0x3815, 0x01},
> > +	{0x3816, 0x00},
> > +	{0x3817, 0x00},
> > +	{0x3818, 0x00},
> > +	{0x3819, 0x00},
> > +	{0x3820, 0x80},
> > +	{0x3821, 0x47},
> > +	{0x382a, 0x03},
> > +	{0x382b, 0x01},
> > +	{0x3830, 0x06},
> > +	{0x3836, 0x02},
> > +	{0x3862, 0x04},
> > +	{0x3863, 0x08},
> > +	{0x3cc0, 0x33},
> > +	{0x3d85, 0x17},
> > +	{0x3d8c, 0x73},
> > +	{0x3d8d, 0xde},
> > +	{0x4001, 0xe0},
> > +	{0x4003, 0x40},
> > +	{0x4008, 0x00},
> > +	{0x4009, 0x05},
> > +	{0x400a, 0x00},
> > +	{0x400b, 0x84},
> > +	{0x400f, 0x80},
> > +	{0x4010, 0xf0},
> > +	{0x4011, 0xff},
> > +	{0x4012, 0x02},
> > +	{0x4013, 0x01},
> > +	{0x4014, 0x01},
> > +	{0x4015, 0x01},
> > +	{0x4042, 0x00},
> > +	{0x4043, 0x80},
> > +	{0x4044, 0x00},
> > +	{0x4045, 0x80},
> > +	{0x4046, 0x00},
> > +	{0x4047, 0x80},
> > +	{0x4048, 0x00},
> > +	{0x4049, 0x80},
> > +	{0x4041, 0x03},
> > +	{0x404c, 0x20},
> > +	{0x404d, 0x00},
> > +	{0x404e, 0x20},
> > +	{0x4203, 0x80},
> > +	{0x4307, 0x30},
> > +	{0x4317, 0x00},
> > +	{0x4502, 0x50},
> > +	{0x4503, 0x08},
> > +	{0x4601, 0x80},
> > +	{0x4800, 0x44},
> > +	{0x4816, 0x53},
> > +	{0x481b, 0x50},
> > +	{0x481f, 0x27},
> > +	{0x4823, 0x3c},
> > +	{0x482b, 0x00},
> > +	{0x4831, 0x66},
> > +	{0x4837, 0x16},
> > +	{0x483c, 0x0f},
> > +	{0x484b, 0x05},
> > +	{0x5000, 0x77},
> > +	{0x5001, 0x0a},
> > +	{0x5003, 0xc8},
> > +	{0x5004, 0x04},
> > +	{0x5006, 0x00},
> > +	{0x5007, 0x00},
> > +	{0x502e, 0x03},
> > +	{0x5030, 0x41},
> > +	{0x5795, 0x00},
> > +	{0x5796, 0x10},
> > +	{0x5797, 0x10},
> > +	{0x5798, 0x73},
> > +	{0x5799, 0x73},
> > +	{0x579a, 0x00},
> > +	{0x579b, 0x28},
> > +	{0x579c, 0x00},
> > +	{0x579d, 0x16},
> > +	{0x579e, 0x06},
> > +	{0x579f, 0x20},
> > +	{0x57a0, 0x04},
> > +	{0x57a1, 0xa0},
> > +	{0x5780, 0x14},
> > +	{0x5781, 0x0f},
> > +	{0x5782, 0x44},
> > +	{0x5783, 0x02},
> > +	{0x5784, 0x01},
> > +	{0x5785, 0x01},
> > +	{0x5786, 0x00},
> > +	{0x5787, 0x04},
> > +	{0x5788, 0x02},
> > +	{0x5789, 0x0f},
> > +	{0x578a, 0xfd},
> > +	{0x578b, 0xf5},
> > +	{0x578c, 0xf5},
> > +	{0x578d, 0x03},
> > +	{0x578e, 0x08},
> > +	{0x578f, 0x0c},
> > +	{0x5790, 0x08},
> > +	{0x5791, 0x04},
> > +	{0x5792, 0x00},
> > +	{0x5793, 0x52},
> > +	{0x5794, 0xa3},
> > +	{0x59f8, 0x3d},
> > +	{0x5a08, 0x02},
> > +	{0x5b00, 0x02},
> > +	{0x5b01, 0x10},
> > +	{0x5b02, 0x03},
> > +	{0x5b03, 0xcf},
> > +	{0x5b05, 0x6c},
> > +	{0x5e00, 0x00},
> > +	{0x5e10, 0xfc}
> > +};
> > +
> >  static const char * const ov8856_test_pattern_menu[] = {
> >  	"Disabled",
> >  	"Standard Color Bar",
> > @@ -548,6 +976,18 @@ static const struct ov8856_mode supported_modes[] = {
> >  		.link_freq_index = OV8856_LINK_FREQ_720MBPS,
> >  	},
> >  	{
> > +		.width    = 3264,
> > +		.height   = 2448,
> > +		.hts      = 1932,
> > +		.vts_def  = 2482,
> > +		.vts_min  = 2482,
> > +		.reg_list = {
> > +			.num_of_regs = ARRAY_SIZE(mode_3264x2448_regs),
> > +			.regs = mode_3264x2448_regs,
> > +		},
> > +		.link_freq_index = OV8856_LINK_FREQ_720MBPS,
> > +	},
> > +	{
> >  		.width = 1640,
> >  		.height = 1232,
> >  		.hts = 3820,
> > @@ -558,6 +998,18 @@ static const struct ov8856_mode supported_modes[] = {
> >  			.regs = mode_1640x1232_regs,
> >  		},
> >  		.link_freq_index = OV8856_LINK_FREQ_360MBPS,
> > +	},
> > +	{
> > +		.width    = 1632,
> > +		.height   = 1224,
> > +		.hts      = 1932,
> > +		.vts_def  = 2482,
> > +		.vts_min  = 2482,
> > +		.reg_list = {
> > +			.num_of_regs = ARRAY_SIZE(mode_1632x1224_regs),
> > +			.regs = mode_1632x1224_regs,
> > +		},
> > +		.link_freq_index = OV8856_LINK_FREQ_360MBPS,
> >  	}
> >  };
> >  
> > @@ -566,6 +1018,10 @@ struct ov8856 {
> >  	struct media_pad pad;
> >  	struct v4l2_ctrl_handler ctrl_handler;
> >  
> > +	struct clk		*xvclk;
> > +	struct gpio_desc	*reset_gpio;
> > +	struct regulator_bulk_data supplies[OV8856_NUM_SUPPLIES];
> > +
> >  	/* V4L2 Controls */
> >  	struct v4l2_ctrl *link_freq;
> >  	struct v4l2_ctrl *pixel_rate;
> > @@ -576,6 +1032,9 @@ struct ov8856 {
> >  	/* Current mode */
> >  	const struct ov8856_mode *cur_mode;
> >  
> > +	/* module hardware version */
> > +	bool is_1B_module;
> 
> What other hardware versions are there, and what are the differences?
> 

According to OV, there are two MP hardware versions (i.e., 1B and 2A)
for OV8856.
There is one difference between 1B and 2A module - which is 0x3614
register.

> > +
> >  	/* To serialize asynchronus callbacks */
> >  	struct mutex mutex;
> >  
> > @@ -696,6 +1155,24 @@ static int ov8856_test_pattern(struct ov8856 *ov8856, u32 pattern)
> >  				OV8856_REG_VALUE_08BIT, pattern);
> >  }
> >  
> > +static int ov8856_update_otp_reg(struct ov8856 *ov8856)
> > +{
> > +	int ret;
> > +
> > +	ret = ov8856_write_reg(ov8856, OV8856_REG_MODE_SELECT,
> > +			       OV8856_REG_VALUE_08BIT, OV8856_MODE_STREAMING);
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = ov8856_write_reg(ov8856, OV8856_OTP_REG_ONE,
> > +			       OV8856_REG_VALUE_08BIT, OV8856_MODE_STANDBY);
> > +	if (ret)
> > +		return ret;
> > +
> > +	return ov8856_write_reg(ov8856, OV8856_OTP_REG_TWO,
> > +				OV8856_REG_VALUE_08BIT, OV8856_MODE_STREAMING);
> > +}
> 
> What does this do?
> 

R700f is OTP register, the register value corresponds different hardware
version.
Mainly including:
01: 2A: EMI improvement
02: 1B: remove some mask for cost; initial setting cannot share with 1A

To identify sensor chip version, the following steps needs to be done
before reading out R700f.
R0100 write 0x01.
R3d84 write 0x00
R3d81 write 0x01

To make more clear, ov8856_update_otp_reg() would be renamed to
ov8856_check_revision() in next release.

> > +
> >  static int ov8856_set_ctrl(struct v4l2_ctrl *ctrl)
> >  {
> >  	struct ov8856 *ov8856 = container_of(ctrl->handler,
> > @@ -825,7 +1302,13 @@ static void ov8856_update_pad_format(const struct ov8856_mode *mode,
> >  {
> >  	fmt->width = mode->width;
> >  	fmt->height = mode->height;
> > -	fmt->code = MEDIA_BUS_FMT_SGRBG10_1X10;
> > +
> > +	/* Bayer Order is determined by image resolution */
> 
> Ouch. 
> 
> This rather looks like a side effect of vertical cropping. How about
> either cropping one line above or below, to keep the same Bayer order?
> 
> The driver is based on register lists that heavily restricts the
> possibilities of configuring the sensor. The alternative, should more
> free-form configuration be enabled, would be to expose the cropping
> capability to the user --- as well as binning.
> 

Oh, this is quite a long story.
From datasheet, the  Bayer Order should be BGGR, and the whole active
pixel array should be 3264x2448.
In fact, I am a little confused about why there exits another image size
(3280x2464).
Or maybe this is one old sensor version.

+Cc: Ben.
Ben, could help introduce some background at that time?


> > +	if (fmt->width == 3264 || fmt->width == 1632)
> > +		fmt->code = MEDIA_BUS_FMT_SBGGR10_1X10;
> > +	else
> > +		fmt->code = MEDIA_BUS_FMT_SGRBG10_1X10;
> > +
> >  	fmt->field = V4L2_FIELD_NONE;
> >  }
> >  
> > @@ -850,6 +1333,17 @@ static int ov8856_start_streaming(struct ov8856 *ov8856)
> >  		return ret;
> >  	}
> >  
> > +	/* update R3614 for 1B module */
> > +	if (ov8856->is_1B_module) {
> > +		ret = ov8856_write_reg(ov8856, OV8856_CLK_REG,
> > +				       OV8856_REG_VALUE_08BIT,
> > +				       OV8856_CLK_REG_1B_VAL);
> > +		if (ret) {
> > +			dev_err(&client->dev, "failed to set R3614");
> > +			return ret;
> > +		}
> > +	}
> > +
> >  	ret = __v4l2_ctrl_handler_setup(ov8856->sd.ctrl_handler);
> >  	if (ret)
> >  		return ret;
> > @@ -882,6 +1376,8 @@ static int ov8856_set_stream(struct v4l2_subdev *sd, int enable)
> >  	if (ov8856->streaming == enable)
> >  		return 0;
> >  
> > +	dev_dbg(&client->dev, "hardware version: (%d)\n", ov8856->is_1B_module);
> > +
> >  	mutex_lock(&ov8856->mutex);
> >  	if (enable) {
> >  		ret = pm_runtime_get_sync(&client->dev);
> > @@ -908,6 +1404,54 @@ static int ov8856_set_stream(struct v4l2_subdev *sd, int enable)
> >  	return ret;
> >  }
> >  
> > +/* Calculate the delay in us by clock rate and clock cycles */
> > +static inline u32 ov8856_cal_delay(u32 cycles)
> > +{
> > +	return DIV_ROUND_UP(cycles, OV8856_XVCLK_FREQ / 1000 / 1000);
> 
> The frequency is rounded down. As it is used to calculate a delay needed,
> rounding up should be done for the frequency, too.
> 

It seems that OV8856_XVCLK_FREQ / 1000 / 1000 is a rounded-down value.
But Note that here OV8856_XVCLK_FREQ is 24MHz.
So OV8856_XVCLK_FREQ / 1000 / 1000 is exactly an integer value.

> > +}
> > +
> > +static int __ov8856_power_on(struct ov8856 *ov8856)
> > +{
> > +	int ret;
> > +	u32 delay_us;
> > +	struct i2c_client *client = v4l2_get_subdevdata(&ov8856->sd);
> > +
> > +	ret = clk_prepare_enable(ov8856->xvclk);
> > +	if (ret < 0) {
> > +		dev_err(&client->dev, "Failed to enable xvclk\n");
> > +		return ret;
> > +	}
> > +
> > +	gpiod_set_value_cansleep(ov8856->reset_gpio, 1);
> > +
> > +	ret = regulator_bulk_enable(OV8856_NUM_SUPPLIES, ov8856->supplies);
> > +	if (ret < 0) {
> > +		dev_err(&client->dev, "Failed to enable regulators\n");
> > +		goto disable_clk;
> > +	}
> > +
> > +	gpiod_set_value_cansleep(ov8856->reset_gpio, 0);
> > +
> > +	/* 8192 cycles prior to first SCCB transaction */
> > +	delay_us = ov8856_cal_delay(8192);
> > +	usleep_range(delay_us  * 2, delay_us * 4);
> 
> Why multiply by 2?
> 
> Note that the driver still needs to work even if the resources aren't
> visible to the software. That's the case e.g. on ACPI based systems.
> 

Understood.
This issue and other returns would be fixed in next release.

> > +
> > +	return 0;
> > +
> > +disable_clk:
> > +	clk_disable_unprepare(ov8856->xvclk);
> > +
> > +	return ret;
> > +}
> > +
> > +static void __ov8856_power_off(struct ov8856 *ov8856)
> > +{
> > +	clk_disable_unprepare(ov8856->xvclk);
> > +	gpiod_set_value_cansleep(ov8856->reset_gpio, 1);
> > +
> > +	regulator_bulk_disable(OV8856_NUM_SUPPLIES, ov8856->supplies);
> > +}
> > +
> >  static int __maybe_unused ov8856_suspend(struct device *dev)
> >  {
> >  	struct i2c_client *client = to_i2c_client(dev);
> > @@ -915,8 +1459,8 @@ static int __maybe_unused ov8856_suspend(struct device *dev)
> >  	struct ov8856 *ov8856 = to_ov8856(sd);
> >  
> >  	mutex_lock(&ov8856->mutex);
> > -	if (ov8856->streaming)
> > -		ov8856_stop_streaming(ov8856);
> 
> This seems like an unrelated change.
> 

Sorry, there is one concerns.
For set_stream(0), it seems that pm_runtime_put would be called after
ov8856_stop_streaming.
I wonder that whether ov8856_stop_streaming is called twice when device
suspended.

> > +
> > +	__ov8856_power_off(ov8856);
> >  
> >  	mutex_unlock(&ov8856->mutex);
> >  
> > @@ -1089,6 +1633,20 @@ static int ov8856_identify_module(struct ov8856 *ov8856)
> >  		return -ENXIO;
> >  	}
> >  
> > +	/* set R3614 to distinguish harward versions */
> > +	ret = ov8856_update_otp_reg(ov8856);
> > +	if (ret) {
> > +		dev_err(&client->dev, "failed to set otp register");
> > +		return ret;
> > +	}
> > +
> > +	ret = ov8856_read_reg(ov8856, OV8856_OTP_REG,
> > +			      OV8856_REG_VALUE_08BIT, &val);
> > +	if (ret)
> > +		return ret;
> > +
> > +	ov8856->is_1B_module = (val == OV8856_1B_MODULE) ? 1 : 0;
> > +
> >  	return 0;
> >  }
> >  
> > @@ -1164,11 +1722,27 @@ static int ov8856_remove(struct i2c_client *client)
> >  	media_entity_cleanup(&sd->entity);
> >  	v4l2_ctrl_handler_free(sd->ctrl_handler);
> >  	pm_runtime_disable(&client->dev);
> > +	if (!pm_runtime_status_suspended(&client->dev))
> > +		__ov8856_power_off(ov8856);
> > +	pm_runtime_set_suspended(&client->dev);
> >  	mutex_destroy(&ov8856->mutex);
> >  
> >  	return 0;
> >  }
> >  
> > +static int ov8856_configure_regulators(struct ov8856 *ov8856)
> > +{
> > +	struct i2c_client *client = v4l2_get_subdevdata(&ov8856->sd);
> > +	int i;
> 
> unsigned int
> 

Fixed in next release.

> > +
> > +	for (i = 0; i < OV8856_NUM_SUPPLIES; i++)
> > +		ov8856->supplies[i].supply = ov8856_supply_names[i];
> > +
> > +	return devm_regulator_bulk_get(&client->dev,
> > +				       OV8856_NUM_SUPPLIES,
> > +				       ov8856->supplies);
> 
> Remember to put the regulators, too.
> 

Thanks for reminder.
ov8856_power_off would call regulator_bulk_disable.

> > +}
> > +
> >  static int ov8856_probe(struct i2c_client *client)
> >  {
> >  	struct ov8856 *ov8856;
> > @@ -1186,6 +1760,40 @@ static int ov8856_probe(struct i2c_client *client)
> >  		return -ENOMEM;
> >  
> >  	v4l2_i2c_subdev_init(&ov8856->sd, client, &ov8856_subdev_ops);
> > +
> > +	ov8856->xvclk = devm_clk_get(&client->dev, "xvclk");
> > +	if (IS_ERR(ov8856->xvclk)) {
> > +		dev_err(&client->dev, "Failed to get xvclk\n");
> > +		return -EINVAL;
> > +	}
> > +
> > +	ret = clk_set_rate(ov8856->xvclk, OV8856_XVCLK_FREQ);
> > +	if (ret < 0) {
> > +		dev_err(&client->dev, "Failed to set xvclk rate (24MHz)\n");
> > +		return ret;
> > +	}
> > +	if (clk_get_rate(ov8856->xvclk) != OV8856_XVCLK_FREQ)
> > +		dev_warn(&client->dev,
> > +			 "xvclk mismatched, modes are based on 24MHz\n");
> > +
> > +	ov8856->reset_gpio = devm_gpiod_get(&client->dev,
> > +					    "reset",
> 
> Fits on the previous line.
> 

Fixed in next release.

> > +					    GPIOD_OUT_LOW);
> > +	if (IS_ERR(ov8856->reset_gpio)) {
> > +		dev_err(&client->dev, "Failed to get reset-gpios\n");
> > +		return -EINVAL;
> > +	}
> > +
> > +	ret = ov8856_configure_regulators(ov8856);
> > +	if (ret) {
> > +		dev_err(&client->dev, "Failed to get power regulators\n");
> > +		return ret;
> > +	}
> > +
> > +	ret = __ov8856_power_on(ov8856);
> > +	if (ret)
> > +		goto probe_error_v4l2_ctrl_handler_free;
> > +
> >  	ret = ov8856_identify_module(ov8856);
> >  	if (ret) {
> >  		dev_err(&client->dev, "failed to find sensor: %d", ret);
> > @@ -1251,11 +1859,21 @@ static const struct acpi_device_id ov8856_acpi_ids[] = {
> >  MODULE_DEVICE_TABLE(acpi, ov8856_acpi_ids);
> >  #endif
> >  
> > +#if IS_ENABLED(CONFIG_OF)
> > +static const struct of_device_id ov8856_of_match[] = {
> > +	{ .compatible = "ovti,ov8856" },
> > +	{},
> > +};
> > +
> > +MODULE_DEVICE_TABLE(of, ov8856_of_match);
> > +#endif
> > +
> >  static struct i2c_driver ov8856_i2c_driver = {
> >  	.driver = {
> >  		.name = "ov8856",
> >  		.pm = &ov8856_pm_ops,
> >  		.acpi_match_table = ACPI_PTR(ov8856_acpi_ids),
> > +		.of_match_table = of_match_ptr(ov8856_of_match),
> >  	},
> >  	.probe_new = ov8856_probe,
> >  	.remove = ov8856_remove,
> 

Re: [V1, 2/2] media: i2c: Add more sensor mode for ov8856 camera sensor

[Sakari Ailus]

Hi Dongchun,

On Mon, Sep 09, 2019 at 04:46:15PM +0800, Dongchun Zhu wrote:
> Hi Sakari,
> 
> On Thu, 2019-08-08 at 16:53 +0300, Sakari Ailus wrote:
> > Hi Dongchun,
> > 
> > Thanks for the patch.
> > 
> > On Thu, Aug 08, 2019 at 05:22:15PM +0800, dongchun.zhu@mediatek.com wrote:
> > > From: Dongchun Zhu <dongchun.zhu@mediatek.com>
> > > 
> > > This patch mainly adds two more sensor modes for OV8856 image sensor.
> > > The OV8856 driver currently supports output format: 10-bit Raw,
> > > the resolution of 1632*1224 and 3264*2448, and the bayer order of BGGR.
> > > The hardware version also differs in some OTP regiser,
> > > as well as PLL register setting.
> > > 
> > > Signed-off-by: Dongchun Zhu <dongchun.zhu@mediatek.com>
> > > ---
> > >  drivers/media/i2c/ov8856.c | 624 ++++++++++++++++++++++++++++++++++++++++++++-
> > >  1 file changed, 621 insertions(+), 3 deletions(-)
> > > 
> > > diff --git a/drivers/media/i2c/ov8856.c b/drivers/media/i2c/ov8856.c
> > > index cd347d6..e0610b6 100644
> > > --- a/drivers/media/i2c/ov8856.c
> > > +++ b/drivers/media/i2c/ov8856.c
> > > @@ -1,12 +1,15 @@
> > >  // SPDX-License-Identifier: GPL-2.0
> > >  // Copyright (c) 2019 Intel Corporation.
> > >  
> > > +#include <linux/clk.h>
> > >  #include <asm/unaligned.h>
> > >  #include <linux/acpi.h>
> > >  #include <linux/delay.h>
> > > +#include <linux/gpio/consumer.h>
> > >  #include <linux/i2c.h>
> > >  #include <linux/module.h>
> > >  #include <linux/pm_runtime.h>
> > > +#include <linux/regulator/consumer.h>
> > >  #include <media/v4l2-ctrls.h>
> > >  #include <media/v4l2-device.h>
> > >  #include <media/v4l2-fwnode.h>
> > > @@ -19,6 +22,7 @@
> > >  #define OV8856_LINK_FREQ_180MHZ		180000000ULL
> > >  #define OV8856_SCLK			144000000ULL
> > >  #define OV8856_MCLK			19200000
> > > +#define OV8856_XVCLK_FREQ		24000000
> > 
> > The driver currenctly uses, perhaps misleadingly, OV8856_MCLK for this
> > purpose. You could rename the existing MCLK as XVCLK.
> > 
> 
> OV8856_MCLK would be replaced by OV8856_XVCLK in next release.
> 
> > This also means the driver needs to differentiate configurations for 24 and
> > 19,2 MHz which it currently does not do. I think it may make sense to make
> > this a separate patch from the rest.
> > 
> 
> From datasheet, OV8856 could support input clock XVCLK range 6-27MHz.
> But the typical frequency is 24MHz.
> That's the value we now provide.

You'll still need to check for it in the driver, to avoid breaking existing
systems that use another frequency.

...

> > > @@ -566,6 +1018,10 @@ struct ov8856 {
> > >  	struct media_pad pad;
> > >  	struct v4l2_ctrl_handler ctrl_handler;
> > >  
> > > +	struct clk		*xvclk;
> > > +	struct gpio_desc	*reset_gpio;
> > > +	struct regulator_bulk_data supplies[OV8856_NUM_SUPPLIES];
> > > +
> > >  	/* V4L2 Controls */
> > >  	struct v4l2_ctrl *link_freq;
> > >  	struct v4l2_ctrl *pixel_rate;
> > > @@ -576,6 +1032,9 @@ struct ov8856 {
> > >  	/* Current mode */
> > >  	const struct ov8856_mode *cur_mode;
> > >  
> > > +	/* module hardware version */
> > > +	bool is_1B_module;
> > 
> > What other hardware versions are there, and what are the differences?
> > 
> 
> According to OV, there are two MP hardware versions (i.e., 1B and 2A)
> for OV8856.
> There is one difference between 1B and 2A module - which is 0x3614
> register.

Could you document the difference in a comment, and also how the B1 variant
is told apart from the 2A one?

> 
> > > +
> > >  	/* To serialize asynchronus callbacks */
> > >  	struct mutex mutex;
> > >  
> > > @@ -696,6 +1155,24 @@ static int ov8856_test_pattern(struct ov8856 *ov8856, u32 pattern)
> > >  				OV8856_REG_VALUE_08BIT, pattern);
> > >  }
> > >  
> > > +static int ov8856_update_otp_reg(struct ov8856 *ov8856)
> > > +{
> > > +	int ret;
> > > +
> > > +	ret = ov8856_write_reg(ov8856, OV8856_REG_MODE_SELECT,
> > > +			       OV8856_REG_VALUE_08BIT, OV8856_MODE_STREAMING);
> > > +	if (ret)
> > > +		return ret;
> > > +
> > > +	ret = ov8856_write_reg(ov8856, OV8856_OTP_REG_ONE,
> > > +			       OV8856_REG_VALUE_08BIT, OV8856_MODE_STANDBY);
> > > +	if (ret)
> > > +		return ret;
> > > +
> > > +	return ov8856_write_reg(ov8856, OV8856_OTP_REG_TWO,
> > > +				OV8856_REG_VALUE_08BIT, OV8856_MODE_STREAMING);
> > > +}
> > 
> > What does this do?
> > 
> 
> R700f is OTP register, the register value corresponds different hardware
> version.
> Mainly including:
> 01: 2A: EMI improvement
> 02: 1B: remove some mask for cost; initial setting cannot share with 1A

If you're accessing EEPROM here, please tell that.

Do you really need to start streaming to do that? Please add comments to
what do these steps actually achieve.

> 
> To identify sensor chip version, the following steps needs to be done
> before reading out R700f.
> R0100 write 0x01.
> R3d84 write 0x00
> R3d81 write 0x01
> 
> To make more clear, ov8856_update_otp_reg() would be renamed to
> ov8856_check_revision() in next release.

Sounds good to me.

> 
> > > +
> > >  static int ov8856_set_ctrl(struct v4l2_ctrl *ctrl)
> > >  {
> > >  	struct ov8856 *ov8856 = container_of(ctrl->handler,
> > > @@ -825,7 +1302,13 @@ static void ov8856_update_pad_format(const struct ov8856_mode *mode,
> > >  {
> > >  	fmt->width = mode->width;
> > >  	fmt->height = mode->height;
> > > -	fmt->code = MEDIA_BUS_FMT_SGRBG10_1X10;
> > > +
> > > +	/* Bayer Order is determined by image resolution */
> > 
> > Ouch. 
> > 
> > This rather looks like a side effect of vertical cropping. How about
> > either cropping one line above or below, to keep the same Bayer order?
> > 
> > The driver is based on register lists that heavily restricts the
> > possibilities of configuring the sensor. The alternative, should more
> > free-form configuration be enabled, would be to expose the cropping
> > capability to the user --- as well as binning.
> > 
> 
> Oh, this is quite a long story.
> From datasheet, the  Bayer Order should be BGGR, and the whole active
> pixel array should be 3264x2448.
> In fact, I am a little confused about why there exits another image size
> (3280x2464).
> Or maybe this is one old sensor version.
> 
> +Cc: Ben.
> Ben, could help introduce some background at that time?
> 
> 
> > > +	if (fmt->width == 3264 || fmt->width == 1632)
> > > +		fmt->code = MEDIA_BUS_FMT_SBGGR10_1X10;
> > > +	else
> > > +		fmt->code = MEDIA_BUS_FMT_SGRBG10_1X10;
> > > +
> > >  	fmt->field = V4L2_FIELD_NONE;
> > >  }
> > >  
> > > @@ -850,6 +1333,17 @@ static int ov8856_start_streaming(struct ov8856 *ov8856)
> > >  		return ret;
> > >  	}
> > >  
> > > +	/* update R3614 for 1B module */
> > > +	if (ov8856->is_1B_module) {
> > > +		ret = ov8856_write_reg(ov8856, OV8856_CLK_REG,
> > > +				       OV8856_REG_VALUE_08BIT,
> > > +				       OV8856_CLK_REG_1B_VAL);
> > > +		if (ret) {
> > > +			dev_err(&client->dev, "failed to set R3614");
> > > +			return ret;
> > > +		}
> > > +	}
> > > +
> > >  	ret = __v4l2_ctrl_handler_setup(ov8856->sd.ctrl_handler);
> > >  	if (ret)
> > >  		return ret;
> > > @@ -882,6 +1376,8 @@ static int ov8856_set_stream(struct v4l2_subdev *sd, int enable)
> > >  	if (ov8856->streaming == enable)
> > >  		return 0;
> > >  
> > > +	dev_dbg(&client->dev, "hardware version: (%d)\n", ov8856->is_1B_module);
> > > +
> > >  	mutex_lock(&ov8856->mutex);
> > >  	if (enable) {
> > >  		ret = pm_runtime_get_sync(&client->dev);
> > > @@ -908,6 +1404,54 @@ static int ov8856_set_stream(struct v4l2_subdev *sd, int enable)
> > >  	return ret;
> > >  }
> > >  
> > > +/* Calculate the delay in us by clock rate and clock cycles */
> > > +static inline u32 ov8856_cal_delay(u32 cycles)
> > > +{
> > > +	return DIV_ROUND_UP(cycles, OV8856_XVCLK_FREQ / 1000 / 1000);
> > 
> > The frequency is rounded down. As it is used to calculate a delay needed,
> > rounding up should be done for the frequency, too.
> > 
> 
> It seems that OV8856_XVCLK_FREQ / 1000 / 1000 is a rounded-down value.
> But Note that here OV8856_XVCLK_FREQ is 24MHz.
> So OV8856_XVCLK_FREQ / 1000 / 1000 is exactly an integer value.

This breaks already on the frequency already supported by the driver (19,2
MHz).

...

> > > +
> > > +	return 0;
> > > +
> > > +disable_clk:
> > > +	clk_disable_unprepare(ov8856->xvclk);
> > > +
> > > +	return ret;
> > > +}
> > > +
> > > +static void __ov8856_power_off(struct ov8856 *ov8856)
> > > +{
> > > +	clk_disable_unprepare(ov8856->xvclk);
> > > +	gpiod_set_value_cansleep(ov8856->reset_gpio, 1);
> > > +
> > > +	regulator_bulk_disable(OV8856_NUM_SUPPLIES, ov8856->supplies);
> > > +}
> > > +
> > >  static int __maybe_unused ov8856_suspend(struct device *dev)
> > >  {
> > >  	struct i2c_client *client = to_i2c_client(dev);
> > > @@ -915,8 +1459,8 @@ static int __maybe_unused ov8856_suspend(struct device *dev)
> > >  	struct ov8856 *ov8856 = to_ov8856(sd);
> > >  
> > >  	mutex_lock(&ov8856->mutex);
> > > -	if (ov8856->streaming)
> > > -		ov8856_stop_streaming(ov8856);
> > 
> > This seems like an unrelated change.
> > 
> 
> Sorry, there is one concerns.
> For set_stream(0), it seems that pm_runtime_put would be called after
> ov8856_stop_streaming.
> I wonder that whether ov8856_stop_streaming is called twice when device
> suspended.

If you think that's the case, please fix it in a separate patch.

...

> > > +
> > > +	for (i = 0; i < OV8856_NUM_SUPPLIES; i++)
> > > +		ov8856->supplies[i].supply = ov8856_supply_names[i];
> > > +
> > > +	return devm_regulator_bulk_get(&client->dev,
> > > +				       OV8856_NUM_SUPPLIES,
> > > +				       ov8856->supplies);
> > 
> > Remember to put the regulators, too.
> > 
> 
> Thanks for reminder.
> ov8856_power_off would call regulator_bulk_disable.

I missed you were using the devm_ variant. No need to put the regulators
(but disable you'll still need).

-- 
Regards,

Sakari Ailus
sakari.ailus@linux.intel.com

Re: [V1, 2/2] media: i2c: Add more sensor mode for ov8856 camera sensor

[Tomasz Figa]

Hi Dongchun,

On Thu, Aug 08, 2019 at 05:22:15PM +0800, dongchun.zhu@mediatek.com wrote:
> From: Dongchun Zhu <dongchun.zhu@mediatek.com>
> 
> This patch mainly adds two more sensor modes for OV8856 image sensor.
> The OV8856 driver currently supports output format: 10-bit Raw,
> the resolution of 1632*1224 and 3264*2448, and the bayer order of BGGR.
> The hardware version also differs in some OTP regiser,
> as well as PLL register setting.
> 
> Signed-off-by: Dongchun Zhu <dongchun.zhu@mediatek.com>
> ---
>  drivers/media/i2c/ov8856.c | 624 ++++++++++++++++++++++++++++++++++++++++++++-
>  1 file changed, 621 insertions(+), 3 deletions(-)
> 

Thanks for the patch! Please see my comments inline.

> diff --git a/drivers/media/i2c/ov8856.c b/drivers/media/i2c/ov8856.c
> index cd347d6..e0610b6 100644
> --- a/drivers/media/i2c/ov8856.c
> +++ b/drivers/media/i2c/ov8856.c
> @@ -1,12 +1,15 @@
>  // SPDX-License-Identifier: GPL-2.0
>  // Copyright (c) 2019 Intel Corporation.
>  
> +#include <linux/clk.h>
>  #include <asm/unaligned.h>
>  #include <linux/acpi.h>
>  #include <linux/delay.h>
> +#include <linux/gpio/consumer.h>
>  #include <linux/i2c.h>
>  #include <linux/module.h>
>  #include <linux/pm_runtime.h>
> +#include <linux/regulator/consumer.h>
>  #include <media/v4l2-ctrls.h>
>  #include <media/v4l2-device.h>
>  #include <media/v4l2-fwnode.h>
> @@ -19,6 +22,7 @@
>  #define OV8856_LINK_FREQ_180MHZ		180000000ULL
>  #define OV8856_SCLK			144000000ULL
>  #define OV8856_MCLK			19200000
> +#define OV8856_XVCLK_FREQ		24000000
>  #define OV8856_DATA_LANES		4
>  #define OV8856_RGB_DEPTH		10
>  
> @@ -29,6 +33,18 @@
>  #define OV8856_MODE_STANDBY		0x00
>  #define OV8856_MODE_STREAMING		0x01
>  
> +/* define 1B module */
> +#define OV8856_1B_MODULE		0x02
> +
> +/* otp sram register */
> +#define OV8856_OTP_REG			0x700f

This isn't a register. I believe the OTP read-out buffer is at 0x7000 and
0xf is the offset of the byte in the OTP that means the module revision.

> +#define OV8856_OTP_REG_ONE		0x3d84
> +#define OV8856_OTP_REG_TWO		0x3d81

These registers are definitely not "ONE" and "TWO". Please use proper
names as per the datasheet.

> +
> +/* clock register */
> +#define OV8856_CLK_REG			0x3614
> +#define OV8856_CLK_REG_1B_VAL		0x20

Same here. These don't look like the real names of the register and bit
field.

> +
>  /* vertical-timings from sensor */
>  #define OV8856_REG_VTS			0x380e
>  #define OV8856_VTS_MAX			0x7fff
> @@ -64,6 +80,14 @@
>  
>  #define to_ov8856(_sd)			container_of(_sd, struct ov8856, sd)
>  
> +static const char * const ov8856_supply_names[] = {
> +	"dovdd",	/* Digital I/O power */
> +	"avdd",		/* Analog power */
> +	"dvdd",		/* Digital core power */
> +};
> +
> +#define OV8856_NUM_SUPPLIES ARRAY_SIZE(ov8856_supply_names)
> +
>  enum {
>  	OV8856_LINK_FREQ_720MBPS,
>  	OV8856_LINK_FREQ_360MBPS,
> @@ -316,6 +340,208 @@ static const struct ov8856_reg mode_3280x2464_regs[] = {
>  	{0x5e00, 0x00}
>  };
>  
> +static const struct ov8856_reg mode_3264x2448_regs[] = {
> +	{0x0103, 0x01},
> +	{0x0302, 0x3c},
> +	{0x0303, 0x01},
> +	{0x031e, 0x0c},
> +	{0x3000, 0x00},
> +	{0x300e, 0x00},
> +	{0x3010, 0x00},
> +	{0x3015, 0x84},
> +	{0x3018, 0x72},
> +	{0x3021, 0x23},
> +	{0x3033, 0x24},
> +	{0x3500, 0x00},
> +	{0x3501, 0x9a},
> +	{0x3502, 0x20},
> +	{0x3503, 0x08},
> +	{0x3505, 0x83},
> +	{0x3508, 0x01},
> +	{0x3509, 0x80},
> +	{0x350c, 0x00},
> +	{0x350d, 0x80},
> +	{0x350e, 0x04},
> +	{0x350f, 0x00},
> +	{0x3510, 0x00},
> +	{0x3511, 0x02},
> +	{0x3512, 0x00},
> +	{0x3600, 0x72},
> +	{0x3601, 0x40},
> +	{0x3602, 0x30},
> +	{0x3610, 0xc5},
> +	{0x3611, 0x58},
> +	{0x3612, 0x5c},
> +	{0x3613, 0xca},
> +	{0x3614, 0x60},
> +	{0x3628, 0xff},
> +	{0x3629, 0xff},
> +	{0x362a, 0xff},
> +	{0x3633, 0x10},
> +	{0x3634, 0x10},
> +	{0x3635, 0x10},
> +	{0x3636, 0x10},
> +	{0x3663, 0x08},
> +	{0x3669, 0x34},
> +	{0x366d, 0x00},
> +	{0x366e, 0x10},
> +	{0x3706, 0x86},
> +	{0x370b, 0x7e},
> +	{0x3714, 0x23},
> +	{0x3730, 0x12},
> +	{0x3733, 0x10},
> +	{0x3764, 0x00},
> +	{0x3765, 0x00},
> +	{0x3769, 0x62},
> +	{0x376a, 0x2a},
> +	{0x376b, 0x30},
> +	{0x3780, 0x00},
> +	{0x3781, 0x24},
> +	{0x3782, 0x00},
> +	{0x3783, 0x23},
> +	{0x3798, 0x2f},
> +	{0x37a1, 0x60},
> +	{0x37a8, 0x6a},
> +	{0x37ab, 0x3f},
> +	{0x37c2, 0x04},
> +	{0x37c3, 0xf1},
> +	{0x37c9, 0x80},
> +	{0x37cb, 0x16},
> +	{0x37cc, 0x16},
> +	{0x37cd, 0x16},
> +	{0x37ce, 0x16},
> +	{0x3800, 0x00},
> +	{0x3801, 0x00},
> +	{0x3802, 0x00},
> +	{0x3803, 0x0c},
> +	{0x3804, 0x0c},
> +	{0x3805, 0xdf},
> +	{0x3806, 0x09},
> +	{0x3807, 0xa3},
> +	{0x3808, 0x0c},
> +	{0x3809, 0xc0},
> +	{0x380a, 0x09},
> +	{0x380b, 0x90},
> +	{0x380c, 0x07},
> +	{0x380d, 0x8c},
> +	{0x380e, 0x09},
> +	{0x380f, 0xb2},
> +	{0x3810, 0x00},
> +	{0x3811, 0x04},
> +	{0x3812, 0x00},
> +	{0x3813, 0x02},
> +	{0x3814, 0x01},
> +	{0x3815, 0x01},
> +	{0x3816, 0x00},
> +	{0x3817, 0x00},
> +	{0x3818, 0x00},
> +	{0x3819, 0x00},
> +	{0x3820, 0x80},
> +	{0x3821, 0x46},
> +	{0x382a, 0x01},
> +	{0x382b, 0x01},
> +	{0x3830, 0x06},
> +	{0x3836, 0x02},
> +	{0x3862, 0x04},
> +	{0x3863, 0x08},
> +	{0x3cc0, 0x33},
> +	{0x3d85, 0x17},
> +	{0x3d8c, 0x73},
> +	{0x3d8d, 0xde},
> +	{0x4001, 0xe0},
> +	{0x4003, 0x40},
> +	{0x4008, 0x00},
> +	{0x4009, 0x0b},
> +	{0x400a, 0x00},
> +	{0x400b, 0x84},
> +	{0x400f, 0x80},
> +	{0x4010, 0xf0},
> +	{0x4011, 0xff},
> +	{0x4012, 0x02},
> +	{0x4013, 0x01},
> +	{0x4014, 0x01},
> +	{0x4015, 0x01},
> +	{0x4042, 0x00},
> +	{0x4043, 0x80},
> +	{0x4044, 0x00},
> +	{0x4045, 0x80},
> +	{0x4046, 0x00},
> +	{0x4047, 0x80},
> +	{0x4048, 0x00},
> +	{0x4049, 0x80},
> +	{0x4041, 0x03},
> +	{0x404c, 0x20},
> +	{0x404d, 0x00},
> +	{0x404e, 0x20},
> +	{0x4203, 0x80},
> +	{0x4307, 0x30},
> +	{0x4317, 0x00},
> +	{0x4502, 0x50},
> +	{0x4503, 0x08},
> +	{0x4601, 0x80},
> +	{0x4800, 0x44},
> +	{0x4816, 0x53},
> +	{0x481b, 0x50},
> +	{0x481f, 0x27},
> +	{0x4823, 0x3c},
> +	{0x482b, 0x00},
> +	{0x4831, 0x66},
> +	{0x4837, 0x16},
> +	{0x483c, 0x0f},
> +	{0x484b, 0x05},
> +	{0x5000, 0x77},
> +	{0x5001, 0x0a},
> +	{0x5003, 0xc8},
> +	{0x5004, 0x04},
> +	{0x5006, 0x00},
> +	{0x5007, 0x00},
> +	{0x502e, 0x03},
> +	{0x5030, 0x41},
> +	{0x5780, 0x14},
> +	{0x5781, 0x0f},
> +	{0x5782, 0x44},
> +	{0x5783, 0x02},
> +	{0x5784, 0x01},
> +	{0x5785, 0x01},
> +	{0x5786, 0x00},
> +	{0x5787, 0x04},
> +	{0x5788, 0x02},
> +	{0x5789, 0x0f},
> +	{0x578a, 0xfd},
> +	{0x578b, 0xf5},
> +	{0x578c, 0xf5},
> +	{0x578d, 0x03},
> +	{0x578e, 0x08},
> +	{0x578f, 0x0c},
> +	{0x5790, 0x08},
> +	{0x5791, 0x04},
> +	{0x5792, 0x00},
> +	{0x5793, 0x52},
> +	{0x5794, 0xa3},
> +	{0x5795, 0x02},
> +	{0x5796, 0x20},
> +	{0x5797, 0x20},
> +	{0x5798, 0xd5},
> +	{0x5799, 0xd5},
> +	{0x579a, 0x00},
> +	{0x579b, 0x50},
> +	{0x579c, 0x00},
> +	{0x579d, 0x2c},
> +	{0x579e, 0x0c},
> +	{0x579f, 0x40},
> +	{0x57a0, 0x09},
> +	{0x57a1, 0x40},
> +	{0x59f8, 0x3d},
> +	{0x5a08, 0x02},
> +	{0x5b00, 0x02},
> +	{0x5b01, 0x10},
> +	{0x5b02, 0x03},
> +	{0x5b03, 0xcf},
> +	{0x5b05, 0x6c},
> +	{0x5e00, 0x00},
> +	{0x5e10, 0xfc}
> +};
> +

It would be better if we could find the differences between the two arrays
and handle them incrementally.

[snip]

> +static int ov8856_update_otp_reg(struct ov8856 *ov8856)
> +{
> +	int ret;
> +
> +	ret = ov8856_write_reg(ov8856, OV8856_REG_MODE_SELECT,
> +			       OV8856_REG_VALUE_08BIT, OV8856_MODE_STREAMING);
> +	if (ret)
> +		return ret;
> +
> +	ret = ov8856_write_reg(ov8856, OV8856_OTP_REG_ONE,
> +			       OV8856_REG_VALUE_08BIT, OV8856_MODE_STANDBY);
> +	if (ret)
> +		return ret;
> +
> +	return ov8856_write_reg(ov8856, OV8856_OTP_REG_TWO,
> +				OV8856_REG_VALUE_08BIT, OV8856_MODE_STREAMING);

Hmm, this doesn't sound right. The OTP register doesn't have anything to do
with streaming. Also we should stop streaming at the end.

> +}
> +
>  static int ov8856_set_ctrl(struct v4l2_ctrl *ctrl)
>  {
>  	struct ov8856 *ov8856 = container_of(ctrl->handler,
> @@ -825,7 +1302,13 @@ static void ov8856_update_pad_format(const struct ov8856_mode *mode,
>  {
>  	fmt->width = mode->width;
>  	fmt->height = mode->height;
> -	fmt->code = MEDIA_BUS_FMT_SGRBG10_1X10;
> +
> +	/* Bayer Order is determined by image resolution */
> +	if (fmt->width == 3264 || fmt->width == 1632)

Could we instead set the bayer order in the mode struct?

> +		fmt->code = MEDIA_BUS_FMT_SBGGR10_1X10;
> +	else
> +		fmt->code = MEDIA_BUS_FMT_SGRBG10_1X10;
> +
>  	fmt->field = V4L2_FIELD_NONE;
>  }
>  
> @@ -850,6 +1333,17 @@ static int ov8856_start_streaming(struct ov8856 *ov8856)
>  		return ret;
>  	}
>  
> +	/* update R3614 for 1B module */

What's R3614?

> +	if (ov8856->is_1B_module) {
> +		ret = ov8856_write_reg(ov8856, OV8856_CLK_REG,
> +				       OV8856_REG_VALUE_08BIT,
> +				       OV8856_CLK_REG_1B_VAL);
> +		if (ret) {
> +			dev_err(&client->dev, "failed to set R3614");
> +			return ret;
> +		}
> +	}
> +
>  	ret = __v4l2_ctrl_handler_setup(ov8856->sd.ctrl_handler);
>  	if (ret)
>  		return ret;
> @@ -882,6 +1376,8 @@ static int ov8856_set_stream(struct v4l2_subdev *sd, int enable)
>  	if (ov8856->streaming == enable)
>  		return 0;
>  
> +	dev_dbg(&client->dev, "hardware version: (%d)\n", ov8856->is_1B_module);
> +
>  	mutex_lock(&ov8856->mutex);
>  	if (enable) {
>  		ret = pm_runtime_get_sync(&client->dev);
> @@ -908,6 +1404,54 @@ static int ov8856_set_stream(struct v4l2_subdev *sd, int enable)
>  	return ret;
>  }
>  
> +/* Calculate the delay in us by clock rate and clock cycles */
> +static inline u32 ov8856_cal_delay(u32 cycles)
> +{
> +	return DIV_ROUND_UP(cycles, OV8856_XVCLK_FREQ / 1000 / 1000);
> +}
> +
> +static int __ov8856_power_on(struct ov8856 *ov8856)
> +{
> +	int ret;
> +	u32 delay_us;
> +	struct i2c_client *client = v4l2_get_subdevdata(&ov8856->sd);
> +
> +	ret = clk_prepare_enable(ov8856->xvclk);
> +	if (ret < 0) {
> +		dev_err(&client->dev, "Failed to enable xvclk\n");
> +		return ret;
> +	}
> +
> +	gpiod_set_value_cansleep(ov8856->reset_gpio, 1);

According to my datasheet, this sensor doesn't have a reset pin. The one I
can see there is XSHUTDN, which I would call "n_shutdn" here.

> +
> +	ret = regulator_bulk_enable(OV8856_NUM_SUPPLIES, ov8856->supplies);
> +	if (ret < 0) {
> +		dev_err(&client->dev, "Failed to enable regulators\n");
> +		goto disable_clk;
> +	}
> +
> +	gpiod_set_value_cansleep(ov8856->reset_gpio, 0);

According to the datasheet, XSHUTDN should be 0 for shutdown and 1 for
running. Why is it the other way around here?

> +
> +	/* 8192 cycles prior to first SCCB transaction */
> +	delay_us = ov8856_cal_delay(8192);

If we pass a constant to the function and the function itself only uses
constants inside, could we just define a constant delay instead?

> +	usleep_range(delay_us  * 2, delay_us * 4);

Normally one one just give some small delta here, like +/- 100 us.

> +
> +	return 0;
> +
> +disable_clk:
> +	clk_disable_unprepare(ov8856->xvclk);
> +
> +	return ret;
> +}
> +
> +static void __ov8856_power_off(struct ov8856 *ov8856)
> +{
> +	clk_disable_unprepare(ov8856->xvclk);
> +	gpiod_set_value_cansleep(ov8856->reset_gpio, 1);
> +
> +	regulator_bulk_disable(OV8856_NUM_SUPPLIES, ov8856->supplies);
> +}
> +
>  static int __maybe_unused ov8856_suspend(struct device *dev)
>  {
>  	struct i2c_client *client = to_i2c_client(dev);
> @@ -915,8 +1459,8 @@ static int __maybe_unused ov8856_suspend(struct device *dev)
>  	struct ov8856 *ov8856 = to_ov8856(sd);
>  
>  	mutex_lock(&ov8856->mutex);
> -	if (ov8856->streaming)
> -		ov8856_stop_streaming(ov8856);
> +
> +	__ov8856_power_off(ov8856);

This change is incorrect because it will power off even if the device was
already powered off, causing reference count mismatch. The original code
was okay.

>  
>  	mutex_unlock(&ov8856->mutex);
>  
> @@ -1089,6 +1633,20 @@ static int ov8856_identify_module(struct ov8856 *ov8856)
>  		return -ENXIO;
>  	}
>  
> +	/* set R3614 to distinguish harward versions */

hardware

> +	ret = ov8856_update_otp_reg(ov8856);
> +	if (ret) {
> +		dev_err(&client->dev, "failed to set otp register");
> +		return ret;
> +	}
> +
> +	ret = ov8856_read_reg(ov8856, OV8856_OTP_REG,
> +			      OV8856_REG_VALUE_08BIT, &val);
> +	if (ret)
> +		return ret;
> +
> +	ov8856->is_1B_module = (val == OV8856_1B_MODULE) ? 1 : 0;

I'd rename ov8856_update_otp_reg() to ov8856_check_revision() and move the
few lines above to that function too.

> +
>  	return 0;
>  }
>  
> @@ -1164,11 +1722,27 @@ static int ov8856_remove(struct i2c_client *client)
>  	media_entity_cleanup(&sd->entity);
>  	v4l2_ctrl_handler_free(sd->ctrl_handler);
>  	pm_runtime_disable(&client->dev);
> +	if (!pm_runtime_status_suspended(&client->dev))
> +		__ov8856_power_off(ov8856);
> +	pm_runtime_set_suspended(&client->dev);
>  	mutex_destroy(&ov8856->mutex);
>  
>  	return 0;
>  }
>  
> +static int ov8856_configure_regulators(struct ov8856 *ov8856)
> +{
> +	struct i2c_client *client = v4l2_get_subdevdata(&ov8856->sd);
> +	int i;
> +
> +	for (i = 0; i < OV8856_NUM_SUPPLIES; i++)
> +		ov8856->supplies[i].supply = ov8856_supply_names[i];
> +
> +	return devm_regulator_bulk_get(&client->dev,
> +				       OV8856_NUM_SUPPLIES,
> +				       ov8856->supplies);
> +}

There is not much value in having a dedicated function just to call one
more function. Could you move back to the caller?

> +
>  static int ov8856_probe(struct i2c_client *client)
>  {
>  	struct ov8856 *ov8856;
> @@ -1186,6 +1760,40 @@ static int ov8856_probe(struct i2c_client *client)
>  		return -ENOMEM;
>  
>  	v4l2_i2c_subdev_init(&ov8856->sd, client, &ov8856_subdev_ops);
> +
> +	ov8856->xvclk = devm_clk_get(&client->dev, "xvclk");
> +	if (IS_ERR(ov8856->xvclk)) {
> +		dev_err(&client->dev, "Failed to get xvclk\n");
> +		return -EINVAL;
> +	}
> +
> +	ret = clk_set_rate(ov8856->xvclk, OV8856_XVCLK_FREQ);

We should get the frequency from the DT bindings.

> +	if (ret < 0) {
> +		dev_err(&client->dev, "Failed to set xvclk rate (24MHz)\n");
> +		return ret;
> +	}
> +	if (clk_get_rate(ov8856->xvclk) != OV8856_XVCLK_FREQ)
> +		dev_warn(&client->dev,
> +			 "xvclk mismatched, modes are based on 24MHz\n");
> +
> +	ov8856->reset_gpio = devm_gpiod_get(&client->dev,
> +					    "reset",
> +					    GPIOD_OUT_LOW);
> +	if (IS_ERR(ov8856->reset_gpio)) {
> +		dev_err(&client->dev, "Failed to get reset-gpios\n");
> +		return -EINVAL;
> +	}
> +
> +	ret = ov8856_configure_regulators(ov8856);
> +	if (ret) {
> +		dev_err(&client->dev, "Failed to get power regulators\n");
> +		return ret;
> +	}
> +
> +	ret = __ov8856_power_on(ov8856);
> +	if (ret)
> +		goto probe_error_v4l2_ctrl_handler_free;
> +
>  	ret = ov8856_identify_module(ov8856);
>  	if (ret) {
>  		dev_err(&client->dev, "failed to find sensor: %d", ret);
> @@ -1251,11 +1859,21 @@ static const struct acpi_device_id ov8856_acpi_ids[] = {
>  MODULE_DEVICE_TABLE(acpi, ov8856_acpi_ids);
>  #endif
>  
> +#if IS_ENABLED(CONFIG_OF)
> +static const struct of_device_id ov8856_of_match[] = {
> +	{ .compatible = "ovti,ov8856" },
> +	{},
> +};
> +

nit: Unnecessary blank line.

Best regards,
Tomasz

Re: [V1, 2/2] media: i2c: Add more sensor mode for ov8856 camera sensor

[Dongchun Zhu]

Hi Tomasz,

On Fri, 2019-08-23 at 19:01 +0900, Tomasz Figa wrote:
> Hi Dongchun,
> 
> On Thu, Aug 08, 2019 at 05:22:15PM +0800, dongchun.zhu@mediatek.com wrote:
> > From: Dongchun Zhu <dongchun.zhu@mediatek.com>
> > 
> > This patch mainly adds two more sensor modes for OV8856 image sensor.
> > The OV8856 driver currently supports output format: 10-bit Raw,
> > the resolution of 1632*1224 and 3264*2448, and the bayer order of BGGR.
> > The hardware version also differs in some OTP regiser,
> > as well as PLL register setting.
> > 
> > Signed-off-by: Dongchun Zhu <dongchun.zhu@mediatek.com>
> > ---
> >  drivers/media/i2c/ov8856.c | 624 ++++++++++++++++++++++++++++++++++++++++++++-
> >  1 file changed, 621 insertions(+), 3 deletions(-)
> > 
> 
> Thanks for the patch! Please see my comments inline.
> 
> > diff --git a/drivers/media/i2c/ov8856.c b/drivers/media/i2c/ov8856.c
> > index cd347d6..e0610b6 100644
> > --- a/drivers/media/i2c/ov8856.c
> > +++ b/drivers/media/i2c/ov8856.c
> > @@ -1,12 +1,15 @@
> >  // SPDX-License-Identifier: GPL-2.0
> >  // Copyright (c) 2019 Intel Corporation.
> >  
> > +#include <linux/clk.h>
> >  #include <asm/unaligned.h>
> >  #include <linux/acpi.h>
> >  #include <linux/delay.h>
> > +#include <linux/gpio/consumer.h>
> >  #include <linux/i2c.h>
> >  #include <linux/module.h>
> >  #include <linux/pm_runtime.h>
> > +#include <linux/regulator/consumer.h>
> >  #include <media/v4l2-ctrls.h>
> >  #include <media/v4l2-device.h>
> >  #include <media/v4l2-fwnode.h>
> > @@ -19,6 +22,7 @@
> >  #define OV8856_LINK_FREQ_180MHZ		180000000ULL
> >  #define OV8856_SCLK			144000000ULL
> >  #define OV8856_MCLK			19200000
> > +#define OV8856_XVCLK_FREQ		24000000
> >  #define OV8856_DATA_LANES		4
> >  #define OV8856_RGB_DEPTH		10
> >  
> > @@ -29,6 +33,18 @@
> >  #define OV8856_MODE_STANDBY		0x00
> >  #define OV8856_MODE_STREAMING		0x01
> >  
> > +/* define 1B module */
> > +#define OV8856_1B_MODULE		0x02
> > +
> > +/* otp sram register */
> > +#define OV8856_OTP_REG			0x700f
> 
> This isn't a register. I believe the OTP read-out buffer is at 0x7000 and
> 0xf is the offset of the byte in the OTP that means the module revision.
> 

Agreed.
I would rename this macro.

> > +#define OV8856_OTP_REG_ONE		0x3d84
> > +#define OV8856_OTP_REG_TWO		0x3d81
> 
> These registers are definitely not "ONE" and "TWO". Please use proper
> names as per the datasheet.
> 

Fixed in next release.

> > +
> > +/* clock register */
> > +#define OV8856_CLK_REG			0x3614
> > +#define OV8856_CLK_REG_1B_VAL		0x20
> 
> Same here. These don't look like the real names of the register and bit
> field.
> 

Fixed in next release.

> > +
> >  /* vertical-timings from sensor */
> >  #define OV8856_REG_VTS			0x380e
> >  #define OV8856_VTS_MAX			0x7fff
> > @@ -64,6 +80,14 @@
> >  
> >  #define to_ov8856(_sd)			container_of(_sd, struct ov8856, sd)
> >  
> > +static const char * const ov8856_supply_names[] = {
> > +	"dovdd",	/* Digital I/O power */
> > +	"avdd",		/* Analog power */
> > +	"dvdd",		/* Digital core power */
> > +};
> > +
> > +#define OV8856_NUM_SUPPLIES ARRAY_SIZE(ov8856_supply_names)
> > +
> >  enum {
> >  	OV8856_LINK_FREQ_720MBPS,
> >  	OV8856_LINK_FREQ_360MBPS,
> > @@ -316,6 +340,208 @@ static const struct ov8856_reg mode_3280x2464_regs[] = {
> >  	{0x5e00, 0x00}
> >  };
> >  
> > +static const struct ov8856_reg mode_3264x2448_regs[] = {
> > +	{0x0103, 0x01},
> > +	{0x0302, 0x3c},
> > +	{0x0303, 0x01},
> > +	{0x031e, 0x0c},
> > +	{0x3000, 0x00},
> > +	{0x300e, 0x00},
> > +	{0x3010, 0x00},
> > +	{0x3015, 0x84},
> > +	{0x3018, 0x72},
> > +	{0x3021, 0x23},
> > +	{0x3033, 0x24},
> > +	{0x3500, 0x00},
> > +	{0x3501, 0x9a},
> > +	{0x3502, 0x20},
> > +	{0x3503, 0x08},
> > +	{0x3505, 0x83},
> > +	{0x3508, 0x01},
> > +	{0x3509, 0x80},
> > +	{0x350c, 0x00},
> > +	{0x350d, 0x80},
> > +	{0x350e, 0x04},
> > +	{0x350f, 0x00},
> > +	{0x3510, 0x00},
> > +	{0x3511, 0x02},
> > +	{0x3512, 0x00},
> > +	{0x3600, 0x72},
> > +	{0x3601, 0x40},
> > +	{0x3602, 0x30},
> > +	{0x3610, 0xc5},
> > +	{0x3611, 0x58},
> > +	{0x3612, 0x5c},
> > +	{0x3613, 0xca},
> > +	{0x3614, 0x60},
> > +	{0x3628, 0xff},
> > +	{0x3629, 0xff},
> > +	{0x362a, 0xff},
> > +	{0x3633, 0x10},
> > +	{0x3634, 0x10},
> > +	{0x3635, 0x10},
> > +	{0x3636, 0x10},
> > +	{0x3663, 0x08},
> > +	{0x3669, 0x34},
> > +	{0x366d, 0x00},
> > +	{0x366e, 0x10},
> > +	{0x3706, 0x86},
> > +	{0x370b, 0x7e},
> > +	{0x3714, 0x23},
> > +	{0x3730, 0x12},
> > +	{0x3733, 0x10},
> > +	{0x3764, 0x00},
> > +	{0x3765, 0x00},
> > +	{0x3769, 0x62},
> > +	{0x376a, 0x2a},
> > +	{0x376b, 0x30},
> > +	{0x3780, 0x00},
> > +	{0x3781, 0x24},
> > +	{0x3782, 0x00},
> > +	{0x3783, 0x23},
> > +	{0x3798, 0x2f},
> > +	{0x37a1, 0x60},
> > +	{0x37a8, 0x6a},
> > +	{0x37ab, 0x3f},
> > +	{0x37c2, 0x04},
> > +	{0x37c3, 0xf1},
> > +	{0x37c9, 0x80},
> > +	{0x37cb, 0x16},
> > +	{0x37cc, 0x16},
> > +	{0x37cd, 0x16},
> > +	{0x37ce, 0x16},
> > +	{0x3800, 0x00},
> > +	{0x3801, 0x00},
> > +	{0x3802, 0x00},
> > +	{0x3803, 0x0c},
> > +	{0x3804, 0x0c},
> > +	{0x3805, 0xdf},
> > +	{0x3806, 0x09},
> > +	{0x3807, 0xa3},
> > +	{0x3808, 0x0c},
> > +	{0x3809, 0xc0},
> > +	{0x380a, 0x09},
> > +	{0x380b, 0x90},
> > +	{0x380c, 0x07},
> > +	{0x380d, 0x8c},
> > +	{0x380e, 0x09},
> > +	{0x380f, 0xb2},
> > +	{0x3810, 0x00},
> > +	{0x3811, 0x04},
> > +	{0x3812, 0x00},
> > +	{0x3813, 0x02},
> > +	{0x3814, 0x01},
> > +	{0x3815, 0x01},
> > +	{0x3816, 0x00},
> > +	{0x3817, 0x00},
> > +	{0x3818, 0x00},
> > +	{0x3819, 0x00},
> > +	{0x3820, 0x80},
> > +	{0x3821, 0x46},
> > +	{0x382a, 0x01},
> > +	{0x382b, 0x01},
> > +	{0x3830, 0x06},
> > +	{0x3836, 0x02},
> > +	{0x3862, 0x04},
> > +	{0x3863, 0x08},
> > +	{0x3cc0, 0x33},
> > +	{0x3d85, 0x17},
> > +	{0x3d8c, 0x73},
> > +	{0x3d8d, 0xde},
> > +	{0x4001, 0xe0},
> > +	{0x4003, 0x40},
> > +	{0x4008, 0x00},
> > +	{0x4009, 0x0b},
> > +	{0x400a, 0x00},
> > +	{0x400b, 0x84},
> > +	{0x400f, 0x80},
> > +	{0x4010, 0xf0},
> > +	{0x4011, 0xff},
> > +	{0x4012, 0x02},
> > +	{0x4013, 0x01},
> > +	{0x4014, 0x01},
> > +	{0x4015, 0x01},
> > +	{0x4042, 0x00},
> > +	{0x4043, 0x80},
> > +	{0x4044, 0x00},
> > +	{0x4045, 0x80},
> > +	{0x4046, 0x00},
> > +	{0x4047, 0x80},
> > +	{0x4048, 0x00},
> > +	{0x4049, 0x80},
> > +	{0x4041, 0x03},
> > +	{0x404c, 0x20},
> > +	{0x404d, 0x00},
> > +	{0x404e, 0x20},
> > +	{0x4203, 0x80},
> > +	{0x4307, 0x30},
> > +	{0x4317, 0x00},
> > +	{0x4502, 0x50},
> > +	{0x4503, 0x08},
> > +	{0x4601, 0x80},
> > +	{0x4800, 0x44},
> > +	{0x4816, 0x53},
> > +	{0x481b, 0x50},
> > +	{0x481f, 0x27},
> > +	{0x4823, 0x3c},
> > +	{0x482b, 0x00},
> > +	{0x4831, 0x66},
> > +	{0x4837, 0x16},
> > +	{0x483c, 0x0f},
> > +	{0x484b, 0x05},
> > +	{0x5000, 0x77},
> > +	{0x5001, 0x0a},
> > +	{0x5003, 0xc8},
> > +	{0x5004, 0x04},
> > +	{0x5006, 0x00},
> > +	{0x5007, 0x00},
> > +	{0x502e, 0x03},
> > +	{0x5030, 0x41},
> > +	{0x5780, 0x14},
> > +	{0x5781, 0x0f},
> > +	{0x5782, 0x44},
> > +	{0x5783, 0x02},
> > +	{0x5784, 0x01},
> > +	{0x5785, 0x01},
> > +	{0x5786, 0x00},
> > +	{0x5787, 0x04},
> > +	{0x5788, 0x02},
> > +	{0x5789, 0x0f},
> > +	{0x578a, 0xfd},
> > +	{0x578b, 0xf5},
> > +	{0x578c, 0xf5},
> > +	{0x578d, 0x03},
> > +	{0x578e, 0x08},
> > +	{0x578f, 0x0c},
> > +	{0x5790, 0x08},
> > +	{0x5791, 0x04},
> > +	{0x5792, 0x00},
> > +	{0x5793, 0x52},
> > +	{0x5794, 0xa3},
> > +	{0x5795, 0x02},
> > +	{0x5796, 0x20},
> > +	{0x5797, 0x20},
> > +	{0x5798, 0xd5},
> > +	{0x5799, 0xd5},
> > +	{0x579a, 0x00},
> > +	{0x579b, 0x50},
> > +	{0x579c, 0x00},
> > +	{0x579d, 0x2c},
> > +	{0x579e, 0x0c},
> > +	{0x579f, 0x40},
> > +	{0x57a0, 0x09},
> > +	{0x57a1, 0x40},
> > +	{0x59f8, 0x3d},
> > +	{0x5a08, 0x02},
> > +	{0x5b00, 0x02},
> > +	{0x5b01, 0x10},
> > +	{0x5b02, 0x03},
> > +	{0x5b03, 0xcf},
> > +	{0x5b05, 0x6c},
> > +	{0x5e00, 0x00},
> > +	{0x5e10, 0xfc}
> > +};
> > +
> 
> It would be better if we could find the differences between the two arrays
> and handle them incrementally.
> 

This approach is not recommended.

For these two arrays, sensor input clock frequencies (19.2MHz, 24MHz)
are different, corresponding to different PLL register setting.

Besides, there are also some differences in image resolution and
hts/vts, including 0x3614 register that reflecting sensor revision.


> [snip]
> 
> > +static int ov8856_update_otp_reg(struct ov8856 *ov8856)
> > +{
> > +	int ret;
> > +
> > +	ret = ov8856_write_reg(ov8856, OV8856_REG_MODE_SELECT,
> > +			       OV8856_REG_VALUE_08BIT, OV8856_MODE_STREAMING);
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = ov8856_write_reg(ov8856, OV8856_OTP_REG_ONE,
> > +			       OV8856_REG_VALUE_08BIT, OV8856_MODE_STANDBY);
> > +	if (ret)
> > +		return ret;
> > +
> > +	return ov8856_write_reg(ov8856, OV8856_OTP_REG_TWO,
> > +				OV8856_REG_VALUE_08BIT, OV8856_MODE_STREAMING);
> 
> Hmm, this doesn't sound right. The OTP register doesn't have anything to do
> with streaming. Also we should stop streaming at the end.
> 

Sorry for the confusion.
We would rename ov8856_update_otp_reg function.

> > +}
> > +
> >  static int ov8856_set_ctrl(struct v4l2_ctrl *ctrl)
> >  {
> >  	struct ov8856 *ov8856 = container_of(ctrl->handler,
> > @@ -825,7 +1302,13 @@ static void ov8856_update_pad_format(const struct ov8856_mode *mode,
> >  {
> >  	fmt->width = mode->width;
> >  	fmt->height = mode->height;
> > -	fmt->code = MEDIA_BUS_FMT_SGRBG10_1X10;
> > +
> > +	/* Bayer Order is determined by image resolution */
> > +	if (fmt->width == 3264 || fmt->width == 1632)
> 
> Could we instead set the bayer order in the mode struct?
> 

I would have a try...

> > +		fmt->code = MEDIA_BUS_FMT_SBGGR10_1X10;
> > +	else
> > +		fmt->code = MEDIA_BUS_FMT_SGRBG10_1X10;
> > +
> >  	fmt->field = V4L2_FIELD_NONE;
> >  }
> >  
> > @@ -850,6 +1333,17 @@ static int ov8856_start_streaming(struct ov8856 *ov8856)
> >  		return ret;
> >  	}
> >  
> > +	/* update R3614 for 1B module */
> 
> What's R3614?
> 

R3614 is the register 0x3614, which reflects the sensor revision.
For instance, it would be 0x20 for 1B module, while 0x60 for 2A module.

> > +	if (ov8856->is_1B_module) {
> > +		ret = ov8856_write_reg(ov8856, OV8856_CLK_REG,
> > +				       OV8856_REG_VALUE_08BIT,
> > +				       OV8856_CLK_REG_1B_VAL);
> > +		if (ret) {
> > +			dev_err(&client->dev, "failed to set R3614");
> > +			return ret;
> > +		}
> > +	}
> > +
> >  	ret = __v4l2_ctrl_handler_setup(ov8856->sd.ctrl_handler);
> >  	if (ret)
> >  		return ret;
> > @@ -882,6 +1376,8 @@ static int ov8856_set_stream(struct v4l2_subdev *sd, int enable)
> >  	if (ov8856->streaming == enable)
> >  		return 0;
> >  
> > +	dev_dbg(&client->dev, "hardware version: (%d)\n", ov8856->is_1B_module);
> > +
> >  	mutex_lock(&ov8856->mutex);
> >  	if (enable) {
> >  		ret = pm_runtime_get_sync(&client->dev);
> > @@ -908,6 +1404,54 @@ static int ov8856_set_stream(struct v4l2_subdev *sd, int enable)
> >  	return ret;
> >  }
> >  
> > +/* Calculate the delay in us by clock rate and clock cycles */
> > +static inline u32 ov8856_cal_delay(u32 cycles)
> > +{
> > +	return DIV_ROUND_UP(cycles, OV8856_XVCLK_FREQ / 1000 / 1000);
> > +}
> > +
> > +static int __ov8856_power_on(struct ov8856 *ov8856)
> > +{
> > +	int ret;
> > +	u32 delay_us;
> > +	struct i2c_client *client = v4l2_get_subdevdata(&ov8856->sd);
> > +
> > +	ret = clk_prepare_enable(ov8856->xvclk);
> > +	if (ret < 0) {
> > +		dev_err(&client->dev, "Failed to enable xvclk\n");
> > +		return ret;
> > +	}
> > +
> > +	gpiod_set_value_cansleep(ov8856->reset_gpio, 1);
> 
> According to my datasheet, this sensor doesn't have a reset pin. The one I
> can see there is XSHUTDN, which I would call "n_shutdn" here.
> 

I would rename this pin in next release.
BTW, how do you define "n_shutdn" or "shuutdn"?
If GPIO is actively high, then "n_shutdn"?

> > +
> > +	ret = regulator_bulk_enable(OV8856_NUM_SUPPLIES, ov8856->supplies);
> > +	if (ret < 0) {
> > +		dev_err(&client->dev, "Failed to enable regulators\n");
> > +		goto disable_clk;
> > +	}
> > +
> > +	gpiod_set_value_cansleep(ov8856->reset_gpio, 0);
> 
> According to the datasheet, XSHUTDN should be 0 for shutdown and 1 for
> running. Why is it the other way around here?
> 

For GPIO, the definition of bit field of flags defined in DT seems
reversed.
This would be fixed in next release.

> > +
> > +	/* 8192 cycles prior to first SCCB transaction */
> > +	delay_us = ov8856_cal_delay(8192);
> 
> If we pass a constant to the function and the function itself only uses
> constants inside, could we just define a constant delay instead?
> 

This calculation refers to powering up sequence in datasheet.
Did you mean using usleep_range() directly?

> > +	usleep_range(delay_us  * 2, delay_us * 4);
> 
> Normally one one just give some small delta here, like +/- 100 us.
> 

Fixed in next release.

> > +
> > +	return 0;
> > +
> > +disable_clk:
> > +	clk_disable_unprepare(ov8856->xvclk);
> > +
> > +	return ret;
> > +}
> > +
> > +static void __ov8856_power_off(struct ov8856 *ov8856)
> > +{
> > +	clk_disable_unprepare(ov8856->xvclk);
> > +	gpiod_set_value_cansleep(ov8856->reset_gpio, 1);
> > +
> > +	regulator_bulk_disable(OV8856_NUM_SUPPLIES, ov8856->supplies);
> > +}
> > +
> >  static int __maybe_unused ov8856_suspend(struct device *dev)
> >  {
> >  	struct i2c_client *client = to_i2c_client(dev);
> > @@ -915,8 +1459,8 @@ static int __maybe_unused ov8856_suspend(struct device *dev)
> >  	struct ov8856 *ov8856 = to_ov8856(sd);
> >  
> >  	mutex_lock(&ov8856->mutex);
> > -	if (ov8856->streaming)
> > -		ov8856_stop_streaming(ov8856);
> > +
> > +	__ov8856_power_off(ov8856);
> 
> This change is incorrect because it will power off even if the device was
> already powered off, causing reference count mismatch. The original code
> was okay.
> 

Then do we need to power off sensor per power off sequence?
I thought this function would be called by pm_runtime_put when power
count is 0.

> >  
> >  	mutex_unlock(&ov8856->mutex);
> >  
> > @@ -1089,6 +1633,20 @@ static int ov8856_identify_module(struct ov8856 *ov8856)
> >  		return -ENXIO;
> >  	}
> >  
> > +	/* set R3614 to distinguish harward versions */
> 
> hardware
> 

Sorry for the typo.
Fixed in next release.

> > +	ret = ov8856_update_otp_reg(ov8856);
> > +	if (ret) {
> > +		dev_err(&client->dev, "failed to set otp register");
> > +		return ret;
> > +	}
> > +
> > +	ret = ov8856_read_reg(ov8856, OV8856_OTP_REG,
> > +			      OV8856_REG_VALUE_08BIT, &val);
> > +	if (ret)
> > +		return ret;
> > +
> > +	ov8856->is_1B_module = (val == OV8856_1B_MODULE) ? 1 : 0;
> 
> I'd rename ov8856_update_otp_reg() to ov8856_check_revision() and move the
> few lines above to that function too.
> 

Fixed in next release.

> > +
> >  	return 0;
> >  }
> >  
> > @@ -1164,11 +1722,27 @@ static int ov8856_remove(struct i2c_client *client)
> >  	media_entity_cleanup(&sd->entity);
> >  	v4l2_ctrl_handler_free(sd->ctrl_handler);
> >  	pm_runtime_disable(&client->dev);
> > +	if (!pm_runtime_status_suspended(&client->dev))
> > +		__ov8856_power_off(ov8856);
> > +	pm_runtime_set_suspended(&client->dev);
> >  	mutex_destroy(&ov8856->mutex);
> >  
> >  	return 0;
> >  }
> >  
> > +static int ov8856_configure_regulators(struct ov8856 *ov8856)
> > +{
> > +	struct i2c_client *client = v4l2_get_subdevdata(&ov8856->sd);
> > +	int i;
> > +
> > +	for (i = 0; i < OV8856_NUM_SUPPLIES; i++)
> > +		ov8856->supplies[i].supply = ov8856_supply_names[i];
> > +
> > +	return devm_regulator_bulk_get(&client->dev,
> > +				       OV8856_NUM_SUPPLIES,
> > +				       ov8856->supplies);
> > +}
> 
> There is not much value in having a dedicated function just to call one
> more function. Could you move back to the caller?
> 

Fixed in next release.

> > +
> >  static int ov8856_probe(struct i2c_client *client)
> >  {
> >  	struct ov8856 *ov8856;
> > @@ -1186,6 +1760,40 @@ static int ov8856_probe(struct i2c_client *client)
> >  		return -ENOMEM;
> >  
> >  	v4l2_i2c_subdev_init(&ov8856->sd, client, &ov8856_subdev_ops);
> > +
> > +	ov8856->xvclk = devm_clk_get(&client->dev, "xvclk");
> > +	if (IS_ERR(ov8856->xvclk)) {
> > +		dev_err(&client->dev, "Failed to get xvclk\n");
> > +		return -EINVAL;
> > +	}
> > +
> > +	ret = clk_set_rate(ov8856->xvclk, OV8856_XVCLK_FREQ);
> 
> We should get the frequency from the DT bindings.
> 

Fixed in next release.

> > +	if (ret < 0) {
> > +		dev_err(&client->dev, "Failed to set xvclk rate (24MHz)\n");
> > +		return ret;
> > +	}
> > +	if (clk_get_rate(ov8856->xvclk) != OV8856_XVCLK_FREQ)
> > +		dev_warn(&client->dev,
> > +			 "xvclk mismatched, modes are based on 24MHz\n");
> > +
> > +	ov8856->reset_gpio = devm_gpiod_get(&client->dev,
> > +					    "reset",
> > +					    GPIOD_OUT_LOW);
> > +	if (IS_ERR(ov8856->reset_gpio)) {
> > +		dev_err(&client->dev, "Failed to get reset-gpios\n");
> > +		return -EINVAL;
> > +	}
> > +
> > +	ret = ov8856_configure_regulators(ov8856);
> > +	if (ret) {
> > +		dev_err(&client->dev, "Failed to get power regulators\n");
> > +		return ret;
> > +	}
> > +
> > +	ret = __ov8856_power_on(ov8856);
> > +	if (ret)
> > +		goto probe_error_v4l2_ctrl_handler_free;
> > +
> >  	ret = ov8856_identify_module(ov8856);
> >  	if (ret) {
> >  		dev_err(&client->dev, "failed to find sensor: %d", ret);
> > @@ -1251,11 +1859,21 @@ static const struct acpi_device_id ov8856_acpi_ids[] = {
> >  MODULE_DEVICE_TABLE(acpi, ov8856_acpi_ids);
> >  #endif
> >  
> > +#if IS_ENABLED(CONFIG_OF)
> > +static const struct of_device_id ov8856_of_match[] = {
> > +	{ .compatible = "ovti,ov8856" },
> > +	{},
> > +};
> > +
> 
> nit: Unnecessary blank line.
> 

Fixed in next release.

> Best regards,
> Tomasz

Re: [V1, 2/2] media: i2c: Add more sensor mode for ov8856 camera sensor

[Tomasz Figa]

Hi Dongchun,

On Mon, Sep 9, 2019 at 6:27 PM Dongchun Zhu <dongchun.zhu@mediatek.com> wrote:
>
> Hi Tomasz,
>
> On Fri, 2019-08-23 at 19:01 +0900, Tomasz Figa wrote:
> > Hi Dongchun,
> >
> > On Thu, Aug 08, 2019 at 05:22:15PM +0800, dongchun.zhu@mediatek.com wrote:
[snip]
> > > +
> > >  /* vertical-timings from sensor */
> > >  #define OV8856_REG_VTS                     0x380e
> > >  #define OV8856_VTS_MAX                     0x7fff
> > > @@ -64,6 +80,14 @@
> > >
> > >  #define to_ov8856(_sd)                     container_of(_sd, struct ov8856, sd)
> > >
> > > +static const char * const ov8856_supply_names[] = {
> > > +   "dovdd",        /* Digital I/O power */
> > > +   "avdd",         /* Analog power */
> > > +   "dvdd",         /* Digital core power */
> > > +};
> > > +
> > > +#define OV8856_NUM_SUPPLIES ARRAY_SIZE(ov8856_supply_names)
> > > +
> > >  enum {
> > >     OV8856_LINK_FREQ_720MBPS,
> > >     OV8856_LINK_FREQ_360MBPS,
> > > @@ -316,6 +340,208 @@ static const struct ov8856_reg mode_3280x2464_regs[] = {
> > >     {0x5e00, 0x00}
> > >  };
> > >
> > > +static const struct ov8856_reg mode_3264x2448_regs[] = {
[snip]
> > > +};
> > > +
> >
> > It would be better if we could find the differences between the two arrays
> > and handle them incrementally.
> >
>
> This approach is not recommended.
>

Not recommended by whom? :) I myself recommend that approach.

I'm sorry, but I'm going to NACK this patch (including the
chromeos-4.19 tree), unless there is a very good technical reason not
to do it the way I'm suggesting. The other drivers do it that way and
I see no reason why this one should be an exception.

> For these two arrays, sensor input clock frequencies (19.2MHz, 24MHz)
> are different, corresponding to different PLL register setting.
>
> Besides, there are also some differences in image resolution and
> hts/vts, including 0x3614 register that reflecting sensor revision.
>

What would be the reason preventing us from handling that in driver code?

Note that I do _not_ mean just taking addresses and values that are
different and putting them to a separate array. What I'm asking for is
to handle the differences in a programmatic way - with dedicated code
in the driver setting appropriate registers.

[snip]

> > > +           fmt->code = MEDIA_BUS_FMT_SBGGR10_1X10;
> > > +   else
> > > +           fmt->code = MEDIA_BUS_FMT_SGRBG10_1X10;
> > > +
> > >     fmt->field = V4L2_FIELD_NONE;
> > >  }
> > >
> > > @@ -850,6 +1333,17 @@ static int ov8856_start_streaming(struct ov8856 *ov8856)
> > >             return ret;
> > >     }
> > >
> > > +   /* update R3614 for 1B module */
> >
> > What's R3614?
> >
>
> R3614 is the register 0x3614, which reflects the sensor revision.
> For instance, it would be 0x20 for 1B module, while 0x60 for 2A module.
>

My point is - this comment doesn't mean anything for a person reading
it. The code below is actually more meaningful - you can see that the
clock settings register is written with a value for 1B.

> > > +   if (ov8856->is_1B_module) {
> > > +           ret = ov8856_write_reg(ov8856, OV8856_CLK_REG,
> > > +                                  OV8856_REG_VALUE_08BIT,
> > > +                                  OV8856_CLK_REG_1B_VAL);

Please define this value according to what it means, not a fixed
constant for 1B sensor revision.

> > > +           if (ret) {
> > > +                   dev_err(&client->dev, "failed to set R3614");
> > > +                   return ret;
> > > +           }
> > > +   }
> > > +
> > >     ret = __v4l2_ctrl_handler_setup(ov8856->sd.ctrl_handler);
> > >     if (ret)
> > >             return ret;
> > > @@ -882,6 +1376,8 @@ static int ov8856_set_stream(struct v4l2_subdev *sd, int enable)
> > >     if (ov8856->streaming == enable)
> > >             return 0;
> > >
> > > +   dev_dbg(&client->dev, "hardware version: (%d)\n", ov8856->is_1B_module);
> > > +
> > >     mutex_lock(&ov8856->mutex);
> > >     if (enable) {
> > >             ret = pm_runtime_get_sync(&client->dev);
> > > @@ -908,6 +1404,54 @@ static int ov8856_set_stream(struct v4l2_subdev *sd, int enable)
> > >     return ret;
> > >  }
> > >
> > > +/* Calculate the delay in us by clock rate and clock cycles */
> > > +static inline u32 ov8856_cal_delay(u32 cycles)
> > > +{
> > > +   return DIV_ROUND_UP(cycles, OV8856_XVCLK_FREQ / 1000 / 1000);
> > > +}
> > > +
> > > +static int __ov8856_power_on(struct ov8856 *ov8856)
> > > +{
> > > +   int ret;
> > > +   u32 delay_us;
> > > +   struct i2c_client *client = v4l2_get_subdevdata(&ov8856->sd);
> > > +
> > > +   ret = clk_prepare_enable(ov8856->xvclk);
> > > +   if (ret < 0) {
> > > +           dev_err(&client->dev, "Failed to enable xvclk\n");
> > > +           return ret;
> > > +   }
> > > +
> > > +   gpiod_set_value_cansleep(ov8856->reset_gpio, 1);
> >
> > According to my datasheet, this sensor doesn't have a reset pin. The one I
> > can see there is XSHUTDN, which I would call "n_shutdn" here.
> >
>
> I would rename this pin in next release.
> BTW, how do you define "n_shutdn" or "shuutdn"?
> If GPIO is actively high, then "n_shutdn"?
>

If the GPIO is active-high (means shutdown on high) then it's just
"shutdn_gpio". However, the datasheet says it's active-low (means
shutdown on low), so that should be "n_shutdn_gpio".

> > > +
> > > +   ret = regulator_bulk_enable(OV8856_NUM_SUPPLIES, ov8856->supplies);
> > > +   if (ret < 0) {
> > > +           dev_err(&client->dev, "Failed to enable regulators\n");
> > > +           goto disable_clk;
> > > +   }
> > > +
> > > +   gpiod_set_value_cansleep(ov8856->reset_gpio, 0);
> >
> > According to the datasheet, XSHUTDN should be 0 for shutdown and 1 for
> > running. Why is it the other way around here?
> >
>
> For GPIO, the definition of bit field of flags defined in DT seems
> reversed.
> This would be fixed in next release.
>
> > > +
> > > +   /* 8192 cycles prior to first SCCB transaction */
> > > +   delay_us = ov8856_cal_delay(8192);
> >
> > If we pass a constant to the function and the function itself only uses
> > constants inside, could we just define a constant delay instead?
> >
>
> This calculation refers to powering up sequence in datasheet.
> Did you mean using usleep_range() directly?

My point is, we can just

#define OV8856_SCCB_INIT_DELAY_US    (8192 * [...])

[...]

usleep_range(OV8856_SCCB_INIT_DELAY_US, OV8856_SCCB_INIT_DELAY_US + 200);

>
> > > +   usleep_range(delay_us  * 2, delay_us * 4);
> >
> > Normally one one just give some small delta here, like +/- 100 us.
> >
>
> Fixed in next release.
>
> > > +
> > > +   return 0;
> > > +
> > > +disable_clk:
> > > +   clk_disable_unprepare(ov8856->xvclk);
> > > +
> > > +   return ret;
> > > +}
> > > +
> > > +static void __ov8856_power_off(struct ov8856 *ov8856)
> > > +{
> > > +   clk_disable_unprepare(ov8856->xvclk);
> > > +   gpiod_set_value_cansleep(ov8856->reset_gpio, 1);
> > > +
> > > +   regulator_bulk_disable(OV8856_NUM_SUPPLIES, ov8856->supplies);
> > > +}
> > > +
> > >  static int __maybe_unused ov8856_suspend(struct device *dev)
> > >  {
> > >     struct i2c_client *client = to_i2c_client(dev);
> > > @@ -915,8 +1459,8 @@ static int __maybe_unused ov8856_suspend(struct device *dev)
> > >     struct ov8856 *ov8856 = to_ov8856(sd);
> > >
> > >     mutex_lock(&ov8856->mutex);
> > > -   if (ov8856->streaming)
> > > -           ov8856_stop_streaming(ov8856);
> > > +
> > > +   __ov8856_power_off(ov8856);
> >
> > This change is incorrect because it will power off even if the device was
> > already powered off, causing reference count mismatch. The original code
> > was okay.
> >
>
> Then do we need to power off sensor per power off sequence?
> I thought this function would be called by pm_runtime_put when power
> count is 0.
>

This is the system suspend callback, not runtime suspend callback.
It's only called when the system goes to sleep.

> > >
> > >     mutex_unlock(&ov8856->mutex);
> > >
> > > @@ -1089,6 +1633,20 @@ static int ov8856_identify_module(struct ov8856 *ov8856)
> > >             return -ENXIO;
> > >     }
> > >
> > > +   /* set R3614 to distinguish harward versions */
> >
> > hardware
> >
>
> Sorry for the typo.
> Fixed in next release.
>

Also a similar comment for R3614, as above. It doesn't have any
meaning to someone without the datasheet in front of them. Please just
remove it.

Best regards,
Tomasz