[PATCH v1 1/3] media: i2c: imx274: Fix Y_OUT_SIZE register setting

[PATCH v1 1/3] media: i2c: imx274: Fix Y_OUT_SIZE register setting

[Sowjanya Komatineni]

Current driver sets Y_OUT_SIZE to crop height + 8 and seeing long frame
errors on the receiver size as expected height on reciever is crop height.

As per Sony IMX274 Y_OUT_SIZE should be the height of effective
image output from the sensor which are the actual total lines
sent over MIPI CSI to receiver.

So, Y_OUT_SIZE should be same as crop height and this patch fixes it.

Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 drivers/media/i2c/imx274.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/i2c/imx274.c b/drivers/media/i2c/imx274.c
index e6aa9f3..55869ff 100644
--- a/drivers/media/i2c/imx274.c
+++ b/drivers/media/i2c/imx274.c
@@ -1163,7 +1163,7 @@ static int imx274_apply_trimming(struct stimx274 *imx274)
 		(-imx274->crop.top / 2) : (imx274->crop.top / 2);
 	v_cut = (IMX274_MAX_HEIGHT - imx274->crop.height) / 2;
 	write_v_size = imx274->crop.height + 22;
-	y_out_size   = imx274->crop.height + 14;
+	y_out_size   = imx274->crop.height;
 
 	err = imx274_write_mbreg(imx274, IMX274_HMAX_REG_LSB, hmax, 2);
 	if (!err)
-- 
2.7.4

[PATCH v1 2/3] dt-bindings: media: imx274: Add optional xclk and supplies

[Sowjanya Komatineni]

This patch adds IMX274 optional external clock input and voltage
supplies to device tree bindings.

Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 Documentation/devicetree/bindings/media/i2c/imx274.txt | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/Documentation/devicetree/bindings/media/i2c/imx274.txt b/Documentation/devicetree/bindings/media/i2c/imx274.txt
index 80f2e89..ee427f5 100644
--- a/Documentation/devicetree/bindings/media/i2c/imx274.txt
+++ b/Documentation/devicetree/bindings/media/i2c/imx274.txt
@@ -13,6 +13,11 @@ Required Properties:
 
 Optional Properties:
 - reset-gpios: Sensor reset GPIO
+- clocks: Reference to the xclk clock.
+- clock-names: Should be "xclk".
+- VANA-supply: Sensor 2.8v analog supply.
+- VDIG-supply: Sensor 1.8v digital core supply.
+- VDDL-supply: Sensor digital IO 1.2v supply.
 
 The imx274 device node should contain one 'port' child node with
 an 'endpoint' subnode. For further reading on port node refer to
-- 
2.7.4

[PATCH v1 3/3] media: i2c: imx274: Add IMX274 power on and off sequence

[Sowjanya Komatineni]

IMX274 has VANA analog 2.8V supply, VDIG digital core 1.8V supply,
and VDDL digital io 1.2V supply which are optional based on camera
module design.

IMX274 also need external 24Mhz clock and is optional based on
camera module design.

This patch adds support for IMX274 power on and off to enable and
disable these supplies and external clock.

Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 drivers/media/i2c/imx274.c | 170 ++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 167 insertions(+), 3 deletions(-)

diff --git a/drivers/media/i2c/imx274.c b/drivers/media/i2c/imx274.c
index 55869ff..8a34c07 100644
--- a/drivers/media/i2c/imx274.c
+++ b/drivers/media/i2c/imx274.c
@@ -19,6 +19,7 @@
 #include <linux/module.h>
 #include <linux/of_gpio.h>
 #include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
 #include <linux/slab.h>
 #include <linux/v4l2-mediabus.h>
 #include <linux/videodev2.h>
@@ -27,6 +28,8 @@
 #include <media/v4l2-device.h>
 #include <media/v4l2-subdev.h>
 
+#define IMX274_DEFAULT_CLK_FREQ			24000000
+
 /*
  * See "SHR, SVR Setting" in datasheet
  */
@@ -501,6 +504,10 @@ struct imx274_ctrls {
  * @frame_rate: V4L2 frame rate structure
  * @regmap: Pointer to regmap structure
  * @reset_gpio: Pointer to reset gpio
+ * @vana_supply: VANA analog supply regulator
+ * @vdig_supply: VDIG digital core supply regulator
+ * @vddl_supply: VDDL digital io supply regulator
+ * @xclk: system clock to imx274
  * @lock: Mutex structure
  * @mode: Parameters for the selected readout mode
  */
@@ -514,6 +521,10 @@ struct stimx274 {
 	struct v4l2_fract frame_interval;
 	struct regmap *regmap;
 	struct gpio_desc *reset_gpio;
+	struct regulator *vana_supply;
+	struct regulator *vdig_supply;
+	struct regulator *vddl_supply;
+	struct clk *xclk;
 	struct mutex lock; /* mutex lock for operations */
 	const struct imx274_mode *mode;
 };
@@ -767,6 +778,138 @@ static void imx274_reset(struct stimx274 *priv, int rst)
 	usleep_range(IMX274_RESET_DELAY1, IMX274_RESET_DELAY2);
 }
 
+/*
+ * imx274_power_on - Function called to power on the sensor
+ * @imx274: Pointer to device structure
+ */
+static int imx274_power_on(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct v4l2_subdev *sd = i2c_get_clientdata(client);
+	struct stimx274 *imx274 = to_imx274(sd);
+	int ret;
+
+	ret = clk_prepare_enable(imx274->xclk);
+	if (ret) {
+		dev_err(&imx274->client->dev, "Failed to enable clock\n");
+		return ret;
+	}
+
+	if (imx274->vana_supply) {
+		ret = regulator_enable(imx274->vana_supply);
+		if (ret < 0) {
+			dev_err(&imx274->client->dev,
+				"Failed to enable VANA supply: %d\n", ret);
+			goto disable_clk;
+		}
+	}
+
+	if (imx274->vdig_supply) {
+		ret = regulator_enable(imx274->vdig_supply);
+		if (ret < 0) {
+			dev_err(&imx274->client->dev,
+				"Failed to enable VDIG supply: %d\n", ret);
+			goto disable_vana_reg;
+		}
+	}
+
+	if (imx274->vddl_supply) {
+		ret = regulator_enable(imx274->vddl_supply);
+		if (ret < 0) {
+			dev_err(&imx274->client->dev,
+				"Failed to enable VDDL supply: %d\n", ret);
+			goto disable_vdig_reg;
+		}
+	}
+
+	usleep_range(1, 2);
+	imx274_reset(imx274, 1);
+
+	return 0;
+
+disable_vdig_reg:
+	if (imx274->vdig_supply)
+		regulator_disable(imx274->vdig_supply);
+disable_vana_reg:
+	if (imx274->vana_supply)
+		regulator_disable(imx274->vana_supply);
+disable_clk:
+	clk_disable_unprepare(imx274->xclk);
+	return ret;
+}
+
+/*
+ * imx274_power_off - Function called to power off the sensor
+ * @imx274: Pointer to device structure
+ */
+static int imx274_power_off(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct v4l2_subdev *sd = i2c_get_clientdata(client);
+	struct stimx274 *imx274 = to_imx274(sd);
+
+	imx274_reset(imx274, 0);
+
+	if (imx274->vddl_supply)
+		regulator_disable(imx274->vddl_supply);
+
+	if (imx274->vdig_supply)
+		regulator_disable(imx274->vdig_supply);
+
+	if (imx274->vana_supply)
+		regulator_disable(imx274->vana_supply);
+
+	clk_disable_unprepare(imx274->xclk);
+
+	return 0;
+}
+
+static int imx274_get_regulators(struct device *dev, struct stimx274 *imx274)
+{
+	int i;
+
+	imx274->vana_supply = devm_regulator_get_optional(dev, "VANA");
+	if (IS_ERR(imx274->vana_supply)) {
+		if (PTR_ERR(imx274->vana_supply) != -ENODEV) {
+			if (PTR_ERR(imx274->vana_supply) != -EPROBE_DEFER)
+				dev_err(&imx274->client->dev,
+					"Failed to get VANA supply: %ld\n",
+					PTR_ERR(imx274->vana_supply));
+			return PTR_ERR(imx274->vana_supply);
+		}
+
+		imx274->vana_supply = NULL;
+	}
+
+	imx274->vdig_supply = devm_regulator_get_optional(dev, "VDIG");
+	if (IS_ERR(imx274->vdig_supply)) {
+		if (PTR_ERR(imx274->vdig_supply) != -ENODEV) {
+			if (PTR_ERR(imx274->vdig_supply) != -EPROBE_DEFER)
+				dev_err(&imx274->client->dev,
+					"Failed to get VDIG supply: %ld\n",
+					PTR_ERR(imx274->vdig_supply));
+			return PTR_ERR(imx274->vdig_supply);
+		}
+
+		imx274->vdig_supply = NULL;
+	}
+
+	imx274->vddl_supply = devm_regulator_get_optional(dev, "VDDL");
+	if (IS_ERR(imx274->vddl_supply)) {
+		if (PTR_ERR(imx274->vddl_supply) != -ENODEV) {
+			if (PTR_ERR(imx274->vddl_supply) != -EPROBE_DEFER)
+				dev_err(&imx274->client->dev,
+					"Failed to get VDIG supply: %ld\n",
+					PTR_ERR(imx274->vddl_supply));
+			return PTR_ERR(imx274->vddl_supply);
+		}
+
+		imx274->vddl_supply = NULL;
+	}
+
+	return 0;
+}
+
 /**
  * imx274_s_ctrl - This is used to set the imx274 V4L2 controls
  * @ctrl: V4L2 control to be set
@@ -1836,6 +1979,19 @@ static int imx274_probe(struct i2c_client *client)
 
 	mutex_init(&imx274->lock);
 
+	imx274->xclk = devm_clk_get_optional(&client->dev, "xclk");
+	ret = clk_set_rate(imx274->xclk, IMX274_DEFAULT_CLK_FREQ);
+	if (ret < 0) {
+		dev_err(&client->dev, "Failed to set xclk rate\n");
+		return ret;
+	}
+
+	ret = imx274_get_regulators(&client->dev, imx274);
+	if (ret) {
+		dev_err(&client->dev, "Failed to get power regulators, err: %d\n", ret);
+		return ret;
+	}
+
 	/* initialize format */
 	imx274->mode = &imx274_modes[IMX274_DEFAULT_BINNING];
 	imx274->crop.width = IMX274_MAX_WIDTH;
@@ -1883,15 +2039,20 @@ static int imx274_probe(struct i2c_client *client)
 		goto err_me;
 	}
 
-	/* pull sensor out of reset */
-	imx274_reset(imx274, 1);
+	/* power on the sensor */
+	ret = imx274_power_on(&client->dev);
+	if (ret < 0) {
+		dev_err(&client->dev,
+			"%s : imx274 power on failed\n", __func__);
+		goto err_me;
+	}
 
 	/* initialize controls */
 	ret = v4l2_ctrl_handler_init(&imx274->ctrls.handler, 4);
 	if (ret < 0) {
 		dev_err(&client->dev,
 			"%s : ctrl handler init Failed\n", __func__);
-		goto err_me;
+		goto err_power_off;
 	}
 
 	imx274->ctrls.handler.lock = &imx274->lock;
@@ -1958,6 +2119,8 @@ static int imx274_probe(struct i2c_client *client)
 
 err_ctrls:
 	v4l2_ctrl_handler_free(&imx274->ctrls.handler);
+err_power_off:
+	imx274_power_off(&client->dev);
 err_me:
 	media_entity_cleanup(&sd->entity);
 err_regmap:
@@ -1975,6 +2138,7 @@ static int imx274_remove(struct i2c_client *client)
 
 	v4l2_async_unregister_subdev(sd);
 	v4l2_ctrl_handler_free(&imx274->ctrls.handler);
+	imx274_power_off(&client->dev);
 	media_entity_cleanup(&sd->entity);
 	mutex_destroy(&imx274->lock);
 	return 0;
-- 
2.7.4

Re: [PATCH v1 3/3] media: i2c: imx274: Add IMX274 power on and off sequence

[Luca Ceresoli]

Hi Sowjanya,

your patch looks good, but I have a few comments about the coding style,
see below.

On 15/07/20 06:24, Sowjanya Komatineni wrote:
> IMX274 has VANA analog 2.8V supply, VDIG digital core 1.8V supply,
> and VDDL digital io 1.2V supply which are optional based on camera
> module design.
> 
> IMX274 also need external 24Mhz clock and is optional based on
> camera module design.
> 
> This patch adds support for IMX274 power on and off to enable and
> disable these supplies and external clock.
> 
> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
> ---
>  drivers/media/i2c/imx274.c | 170 ++++++++++++++++++++++++++++++++++++++++++++-
>  1 file changed, 167 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/media/i2c/imx274.c b/drivers/media/i2c/imx274.c
> index 55869ff..8a34c07 100644
> --- a/drivers/media/i2c/imx274.c
> +++ b/drivers/media/i2c/imx274.c
> @@ -19,6 +19,7 @@
>  #include <linux/module.h>
>  #include <linux/of_gpio.h>
>  #include <linux/regmap.h>
> +#include <linux/regulator/consumer.h>
>  #include <linux/slab.h>
>  #include <linux/v4l2-mediabus.h>
>  #include <linux/videodev2.h>
> @@ -27,6 +28,8 @@
>  #include <media/v4l2-device.h>
>  #include <media/v4l2-subdev.h>
>  
> +#define IMX274_DEFAULT_CLK_FREQ			24000000
> +
>  /*
>   * See "SHR, SVR Setting" in datasheet
>   */
> @@ -501,6 +504,10 @@ struct imx274_ctrls {
>   * @frame_rate: V4L2 frame rate structure
>   * @regmap: Pointer to regmap structure
>   * @reset_gpio: Pointer to reset gpio
> + * @vana_supply: VANA analog supply regulator
> + * @vdig_supply: VDIG digital core supply regulator
> + * @vddl_supply: VDDL digital io supply regulator
> + * @xclk: system clock to imx274
>   * @lock: Mutex structure
>   * @mode: Parameters for the selected readout mode
>   */
> @@ -514,6 +521,10 @@ struct stimx274 {
>  	struct v4l2_fract frame_interval;
>  	struct regmap *regmap;
>  	struct gpio_desc *reset_gpio;
> +	struct regulator *vana_supply;
> +	struct regulator *vdig_supply;
> +	struct regulator *vddl_supply;
> +	struct clk *xclk;
>  	struct mutex lock; /* mutex lock for operations */
>  	const struct imx274_mode *mode;
>  };
> @@ -767,6 +778,138 @@ static void imx274_reset(struct stimx274 *priv, int rst)
>  	usleep_range(IMX274_RESET_DELAY1, IMX274_RESET_DELAY2);
>  }
>  
> +/*
> + * imx274_power_on - Function called to power on the sensor
> + * @imx274: Pointer to device structure
> + */
> +static int imx274_power_on(struct device *dev)
> +{
> +	struct i2c_client *client = to_i2c_client(dev);
> +	struct v4l2_subdev *sd = i2c_get_clientdata(client);
> +	struct stimx274 *imx274 = to_imx274(sd);
> +	int ret;
> +
> +	ret = clk_prepare_enable(imx274->xclk);
> +	if (ret) {
> +		dev_err(&imx274->client->dev, "Failed to enable clock\n");
> +		return ret;
> +	}
> +
> +	if (imx274->vana_supply) {
> +		ret = regulator_enable(imx274->vana_supply);
> +		if (ret < 0) {
> +			dev_err(&imx274->client->dev,
> +				"Failed to enable VANA supply: %d\n", ret);
> +			goto disable_clk;
> +		}
> +	}
> +
> +	if (imx274->vdig_supply) {
> +		ret = regulator_enable(imx274->vdig_supply);
> +		if (ret < 0) {
> +			dev_err(&imx274->client->dev,
> +				"Failed to enable VDIG supply: %d\n", ret);
> +			goto disable_vana_reg;
> +		}
> +	}
> +
> +	if (imx274->vddl_supply) {
> +		ret = regulator_enable(imx274->vddl_supply);
> +		if (ret < 0) {
> +			dev_err(&imx274->client->dev,
> +				"Failed to enable VDDL supply: %d\n", ret);
> +			goto disable_vdig_reg;
> +		}
> +	}
> +
> +	usleep_range(1, 2);
> +	imx274_reset(imx274, 1);
> +
> +	return 0;
> +
> +disable_vdig_reg:
> +	if (imx274->vdig_supply)
> +		regulator_disable(imx274->vdig_supply);
> +disable_vana_reg:
> +	if (imx274->vana_supply)
> +		regulator_disable(imx274->vana_supply);
> +disable_clk:
> +	clk_disable_unprepare(imx274->xclk);
> +	return ret;
> +}
> +
> +/*
> + * imx274_power_off - Function called to power off the sensor
> + * @imx274: Pointer to device structure
> + */
> +static int imx274_power_off(struct device *dev)
> +{
> +	struct i2c_client *client = to_i2c_client(dev);
> +	struct v4l2_subdev *sd = i2c_get_clientdata(client);
> +	struct stimx274 *imx274 = to_imx274(sd);
> +
> +	imx274_reset(imx274, 0);
> +
> +	if (imx274->vddl_supply)
> +		regulator_disable(imx274->vddl_supply);
> +
> +	if (imx274->vdig_supply)
> +		regulator_disable(imx274->vdig_supply);
> +
> +	if (imx274->vana_supply)
> +		regulator_disable(imx274->vana_supply);
> +
> +	clk_disable_unprepare(imx274->xclk);
> +
> +	return 0;
> +}
> +
> +static int imx274_get_regulators(struct device *dev, struct stimx274 *imx274)
> +{

To make code much more readable:

  int err;

> +	int i;
> +
> +	imx274->vana_supply = devm_regulator_get_optional(dev, "VANA");
> +	if (IS_ERR(imx274->vana_supply)) {

  err = PTR_ERR(imx274->vana_supply)

and then use 'err' everywhere in place of PTR_ERR(imx274->vana_supply).

> +		if (PTR_ERR(imx274->vana_supply) != -ENODEV) {
> +			if (PTR_ERR(imx274->vana_supply) != -EPROBE_DEFER)
> +				dev_err(&imx274->client->dev,
> +					"Failed to get VANA supply: %ld\n",
> +					PTR_ERR(imx274->vana_supply));
> +			return PTR_ERR(imx274->vana_supply);
> +		}
> +
> +		imx274->vana_supply = NULL;
> +	}
> +
> +	imx274->vdig_supply = devm_regulator_get_optional(dev, "VDIG");
> +	if (IS_ERR(imx274->vdig_supply)) {
> +		if (PTR_ERR(imx274->vdig_supply) != -ENODEV) {
> +			if (PTR_ERR(imx274->vdig_supply) != -EPROBE_DEFER)
> +				dev_err(&imx274->client->dev,
> +					"Failed to get VDIG supply: %ld\n",
> +					PTR_ERR(imx274->vdig_supply));
> +			return PTR_ERR(imx274->vdig_supply);
> +		}
> +
> +		imx274->vdig_supply = NULL;
> +	}
> +
> +	imx274->vddl_supply = devm_regulator_get_optional(dev, "VDDL");
> +	if (IS_ERR(imx274->vddl_supply)) {
> +		if (PTR_ERR(imx274->vddl_supply) != -ENODEV) {
> +			if (PTR_ERR(imx274->vddl_supply) != -EPROBE_DEFER)
> +				dev_err(&imx274->client->dev,
> +					"Failed to get VDIG supply: %ld\n",
> +					PTR_ERR(imx274->vddl_supply));
> +			return PTR_ERR(imx274->vddl_supply);
> +		}
> +
> +		imx274->vddl_supply = NULL;
> +	}

Here, as well as in imx274_power_on(), you have 3 identical sections for
the 3 regulators. Why not having an array of 3 elements in struct
stimx274 and then access them in a loop? You'll need also the names:

  static const char* regulator_name[3] = { "VANA", "VDIG", "VDDL" };

>  /**
>   * imx274_s_ctrl - This is used to set the imx274 V4L2 controls
>   * @ctrl: V4L2 control to be set
> @@ -1836,6 +1979,19 @@ static int imx274_probe(struct i2c_client *client)
>  
>  	mutex_init(&imx274->lock);
>  
> +	imx274->xclk = devm_clk_get_optional(&client->dev, "xclk");
> +	ret = clk_set_rate(imx274->xclk, IMX274_DEFAULT_CLK_FREQ);

Nitpicking, but I'd move this line closer to the end of the function in
order to set the clock rate only if all the get operations succeeded.

> +	if (ret < 0) {
> +		dev_err(&client->dev, "Failed to set xclk rate\n");
> +		return ret;
> +	}
> +
> +	ret = imx274_get_regulators(&client->dev, imx274);
> +	if (ret) {
> +		dev_err(&client->dev, "Failed to get power regulators, err: %d\n", ret);
> +		return ret;
> +	}
> +
>  	/* initialize format */
>  	imx274->mode = &imx274_modes[IMX274_DEFAULT_BINNING];
>  	imx274->crop.width = IMX274_MAX_WIDTH;
> @@ -1883,15 +2039,20 @@ static int imx274_probe(struct i2c_client *client)
>  		goto err_me;
>  	}
>  
> -	/* pull sensor out of reset */
> -	imx274_reset(imx274, 1);
> +	/* power on the sensor */
> +	ret = imx274_power_on(&client->dev);
> +	if (ret < 0) {
> +		dev_err(&client->dev,
> +			"%s : imx274 power on failed\n", __func__);
> +		goto err_me;
> +	}
>  
>  	/* initialize controls */
>  	ret = v4l2_ctrl_handler_init(&imx274->ctrls.handler, 4);
>  	if (ret < 0) {
>  		dev_err(&client->dev,
>  			"%s : ctrl handler init Failed\n", __func__);
> -		goto err_me;
> +		goto err_power_off;
>  	}
>  
>  	imx274->ctrls.handler.lock = &imx274->lock;
> @@ -1958,6 +2119,8 @@ static int imx274_probe(struct i2c_client *client)
>  
>  err_ctrls:
>  	v4l2_ctrl_handler_free(&imx274->ctrls.handler);
> +err_power_off:
> +	imx274_power_off(&client->dev);
>  err_me:
>  	media_entity_cleanup(&sd->entity);
>  err_regmap:
> @@ -1975,6 +2138,7 @@ static int imx274_remove(struct i2c_client *client)
>  
>  	v4l2_async_unregister_subdev(sd);
>  	v4l2_ctrl_handler_free(&imx274->ctrls.handler);
> +	imx274_power_off(&client->dev);
>  	media_entity_cleanup(&sd->entity);
>  	mutex_destroy(&imx274->lock);
>  	return 0;
> 


-- 
Luca

Re: [PATCH v1 3/3] media: i2c: imx274: Add IMX274 power on and off sequence

[Sowjanya Komatineni]

On 7/15/20 10:46 AM, Luca Ceresoli wrote:
> Hi Sowjanya,
>
> your patch looks good, but I have a few comments about the coding style,
> see below.

Thanks Luca. Will consider them for v2.

>
> On 15/07/20 06:24, Sowjanya Komatineni wrote:
>> IMX274 has VANA analog 2.8V supply, VDIG digital core 1.8V supply,
>> and VDDL digital io 1.2V supply which are optional based on camera
>> module design.
>>
>> IMX274 also need external 24Mhz clock and is optional based on
>> camera module design.
>>
>> This patch adds support for IMX274 power on and off to enable and
>> disable these supplies and external clock.
>>
>> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
>> ---
>>   drivers/media/i2c/imx274.c | 170 ++++++++++++++++++++++++++++++++++++++++++++-
>>   1 file changed, 167 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/media/i2c/imx274.c b/drivers/media/i2c/imx274.c
>> index 55869ff..8a34c07 100644
>> --- a/drivers/media/i2c/imx274.c
>> +++ b/drivers/media/i2c/imx274.c
>> @@ -19,6 +19,7 @@
>>   #include <linux/module.h>
>>   #include <linux/of_gpio.h>
>>   #include <linux/regmap.h>
>> +#include <linux/regulator/consumer.h>
>>   #include <linux/slab.h>
>>   #include <linux/v4l2-mediabus.h>
>>   #include <linux/videodev2.h>
>> @@ -27,6 +28,8 @@
>>   #include <media/v4l2-device.h>
>>   #include <media/v4l2-subdev.h>
>>   
>> +#define IMX274_DEFAULT_CLK_FREQ			24000000
>> +
>>   /*
>>    * See "SHR, SVR Setting" in datasheet
>>    */
>> @@ -501,6 +504,10 @@ struct imx274_ctrls {
>>    * @frame_rate: V4L2 frame rate structure
>>    * @regmap: Pointer to regmap structure
>>    * @reset_gpio: Pointer to reset gpio
>> + * @vana_supply: VANA analog supply regulator
>> + * @vdig_supply: VDIG digital core supply regulator
>> + * @vddl_supply: VDDL digital io supply regulator
>> + * @xclk: system clock to imx274
>>    * @lock: Mutex structure
>>    * @mode: Parameters for the selected readout mode
>>    */
>> @@ -514,6 +521,10 @@ struct stimx274 {
>>   	struct v4l2_fract frame_interval;
>>   	struct regmap *regmap;
>>   	struct gpio_desc *reset_gpio;
>> +	struct regulator *vana_supply;
>> +	struct regulator *vdig_supply;
>> +	struct regulator *vddl_supply;
>> +	struct clk *xclk;
>>   	struct mutex lock; /* mutex lock for operations */
>>   	const struct imx274_mode *mode;
>>   };
>> @@ -767,6 +778,138 @@ static void imx274_reset(struct stimx274 *priv, int rst)
>>   	usleep_range(IMX274_RESET_DELAY1, IMX274_RESET_DELAY2);
>>   }
>>   
>> +/*
>> + * imx274_power_on - Function called to power on the sensor
>> + * @imx274: Pointer to device structure
>> + */
>> +static int imx274_power_on(struct device *dev)
>> +{
>> +	struct i2c_client *client = to_i2c_client(dev);
>> +	struct v4l2_subdev *sd = i2c_get_clientdata(client);
>> +	struct stimx274 *imx274 = to_imx274(sd);
>> +	int ret;
>> +
>> +	ret = clk_prepare_enable(imx274->xclk);
>> +	if (ret) {
>> +		dev_err(&imx274->client->dev, "Failed to enable clock\n");
>> +		return ret;
>> +	}
>> +
>> +	if (imx274->vana_supply) {
>> +		ret = regulator_enable(imx274->vana_supply);
>> +		if (ret < 0) {
>> +			dev_err(&imx274->client->dev,
>> +				"Failed to enable VANA supply: %d\n", ret);
>> +			goto disable_clk;
>> +		}
>> +	}
>> +
>> +	if (imx274->vdig_supply) {
>> +		ret = regulator_enable(imx274->vdig_supply);
>> +		if (ret < 0) {
>> +			dev_err(&imx274->client->dev,
>> +				"Failed to enable VDIG supply: %d\n", ret);
>> +			goto disable_vana_reg;
>> +		}
>> +	}
>> +
>> +	if (imx274->vddl_supply) {
>> +		ret = regulator_enable(imx274->vddl_supply);
>> +		if (ret < 0) {
>> +			dev_err(&imx274->client->dev,
>> +				"Failed to enable VDDL supply: %d\n", ret);
>> +			goto disable_vdig_reg;
>> +		}
>> +	}
>> +
>> +	usleep_range(1, 2);
>> +	imx274_reset(imx274, 1);
>> +
>> +	return 0;
>> +
>> +disable_vdig_reg:
>> +	if (imx274->vdig_supply)
>> +		regulator_disable(imx274->vdig_supply);
>> +disable_vana_reg:
>> +	if (imx274->vana_supply)
>> +		regulator_disable(imx274->vana_supply);
>> +disable_clk:
>> +	clk_disable_unprepare(imx274->xclk);
>> +	return ret;
>> +}
>> +
>> +/*
>> + * imx274_power_off - Function called to power off the sensor
>> + * @imx274: Pointer to device structure
>> + */
>> +static int imx274_power_off(struct device *dev)
>> +{
>> +	struct i2c_client *client = to_i2c_client(dev);
>> +	struct v4l2_subdev *sd = i2c_get_clientdata(client);
>> +	struct stimx274 *imx274 = to_imx274(sd);
>> +
>> +	imx274_reset(imx274, 0);
>> +
>> +	if (imx274->vddl_supply)
>> +		regulator_disable(imx274->vddl_supply);
>> +
>> +	if (imx274->vdig_supply)
>> +		regulator_disable(imx274->vdig_supply);
>> +
>> +	if (imx274->vana_supply)
>> +		regulator_disable(imx274->vana_supply);
>> +
>> +	clk_disable_unprepare(imx274->xclk);
>> +
>> +	return 0;
>> +}
>> +
>> +static int imx274_get_regulators(struct device *dev, struct stimx274 *imx274)
>> +{
> To make code much more readable:
>
>    int err;
>
>> +	int i;
>> +
>> +	imx274->vana_supply = devm_regulator_get_optional(dev, "VANA");
>> +	if (IS_ERR(imx274->vana_supply)) {
>    err = PTR_ERR(imx274->vana_supply)
>
> and then use 'err' everywhere in place of PTR_ERR(imx274->vana_supply).
>
>> +		if (PTR_ERR(imx274->vana_supply) != -ENODEV) {
>> +			if (PTR_ERR(imx274->vana_supply) != -EPROBE_DEFER)
>> +				dev_err(&imx274->client->dev,
>> +					"Failed to get VANA supply: %ld\n",
>> +					PTR_ERR(imx274->vana_supply));
>> +			return PTR_ERR(imx274->vana_supply);
>> +		}
>> +
>> +		imx274->vana_supply = NULL;
>> +	}
>> +
>> +	imx274->vdig_supply = devm_regulator_get_optional(dev, "VDIG");
>> +	if (IS_ERR(imx274->vdig_supply)) {
>> +		if (PTR_ERR(imx274->vdig_supply) != -ENODEV) {
>> +			if (PTR_ERR(imx274->vdig_supply) != -EPROBE_DEFER)
>> +				dev_err(&imx274->client->dev,
>> +					"Failed to get VDIG supply: %ld\n",
>> +					PTR_ERR(imx274->vdig_supply));
>> +			return PTR_ERR(imx274->vdig_supply);
>> +		}
>> +
>> +		imx274->vdig_supply = NULL;
>> +	}
>> +
>> +	imx274->vddl_supply = devm_regulator_get_optional(dev, "VDDL");
>> +	if (IS_ERR(imx274->vddl_supply)) {
>> +		if (PTR_ERR(imx274->vddl_supply) != -ENODEV) {
>> +			if (PTR_ERR(imx274->vddl_supply) != -EPROBE_DEFER)
>> +				dev_err(&imx274->client->dev,
>> +					"Failed to get VDIG supply: %ld\n",
>> +					PTR_ERR(imx274->vddl_supply));
>> +			return PTR_ERR(imx274->vddl_supply);
>> +		}
>> +
>> +		imx274->vddl_supply = NULL;
>> +	}
> Here, as well as in imx274_power_on(), you have 3 identical sections for
> the 3 regulators. Why not having an array of 3 elements in struct
> stimx274 and then access them in a loop? You'll need also the names:
>
>    static const char* regulator_name[3] = { "VANA", "VDIG", "VDDL" };
>
>>   /**
>>    * imx274_s_ctrl - This is used to set the imx274 V4L2 controls
>>    * @ctrl: V4L2 control to be set
>> @@ -1836,6 +1979,19 @@ static int imx274_probe(struct i2c_client *client)
>>   
>>   	mutex_init(&imx274->lock);
>>   
>> +	imx274->xclk = devm_clk_get_optional(&client->dev, "xclk");
>> +	ret = clk_set_rate(imx274->xclk, IMX274_DEFAULT_CLK_FREQ);
> Nitpicking, but I'd move this line closer to the end of the function in
> order to set the clock rate only if all the get operations succeeded.
>
>> +	if (ret < 0) {
>> +		dev_err(&client->dev, "Failed to set xclk rate\n");
>> +		return ret;
>> +	}
>> +
>> +	ret = imx274_get_regulators(&client->dev, imx274);
>> +	if (ret) {
>> +		dev_err(&client->dev, "Failed to get power regulators, err: %d\n", ret);
>> +		return ret;
>> +	}
>> +
>>   	/* initialize format */
>>   	imx274->mode = &imx274_modes[IMX274_DEFAULT_BINNING];
>>   	imx274->crop.width = IMX274_MAX_WIDTH;
>> @@ -1883,15 +2039,20 @@ static int imx274_probe(struct i2c_client *client)
>>   		goto err_me;
>>   	}
>>   
>> -	/* pull sensor out of reset */
>> -	imx274_reset(imx274, 1);
>> +	/* power on the sensor */
>> +	ret = imx274_power_on(&client->dev);
>> +	if (ret < 0) {
>> +		dev_err(&client->dev,
>> +			"%s : imx274 power on failed\n", __func__);
>> +		goto err_me;
>> +	}
>>   
>>   	/* initialize controls */
>>   	ret = v4l2_ctrl_handler_init(&imx274->ctrls.handler, 4);
>>   	if (ret < 0) {
>>   		dev_err(&client->dev,
>>   			"%s : ctrl handler init Failed\n", __func__);
>> -		goto err_me;
>> +		goto err_power_off;
>>   	}
>>   
>>   	imx274->ctrls.handler.lock = &imx274->lock;
>> @@ -1958,6 +2119,8 @@ static int imx274_probe(struct i2c_client *client)
>>   
>>   err_ctrls:
>>   	v4l2_ctrl_handler_free(&imx274->ctrls.handler);
>> +err_power_off:
>> +	imx274_power_off(&client->dev);
>>   err_me:
>>   	media_entity_cleanup(&sd->entity);
>>   err_regmap:
>> @@ -1975,6 +2138,7 @@ static int imx274_remove(struct i2c_client *client)
>>   
>>   	v4l2_async_unregister_subdev(sd);
>>   	v4l2_ctrl_handler_free(&imx274->ctrls.handler);
>> +	imx274_power_off(&client->dev);
>>   	media_entity_cleanup(&sd->entity);
>>   	mutex_destroy(&imx274->lock);
>>   	return 0;
>>
>

Re: [PATCH v1 2/3] dt-bindings: media: imx274: Add optional xclk and supplies

[Luca Ceresoli]

Hi Sowjanya,

On 15/07/20 06:24, Sowjanya Komatineni wrote:
> This patch adds IMX274 optional external clock input and voltage
> supplies to device tree bindings.
> 
> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
> ---
>  Documentation/devicetree/bindings/media/i2c/imx274.txt | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/media/i2c/imx274.txt b/Documentation/devicetree/bindings/media/i2c/imx274.txt
> index 80f2e89..ee427f5 100644
> --- a/Documentation/devicetree/bindings/media/i2c/imx274.txt
> +++ b/Documentation/devicetree/bindings/media/i2c/imx274.txt
> @@ -13,6 +13,11 @@ Required Properties:
>  
>  Optional Properties:
>  - reset-gpios: Sensor reset GPIO
> +- clocks: Reference to the xclk clock.
> +- clock-names: Should be "xclk".

Not sure where the "xclk" name comes from, the datasheet I have calls
the pin "CKIN". Maybe using the same name as the datasheet is better?

Other than that looks good.

-- 
Luca

Re: [PATCH v1 2/3] dt-bindings: media: imx274: Add optional xclk and supplies

[Sowjanya Komatineni]

On 7/15/20 11:50 PM, Luca Ceresoli wrote:
> Hi Sowjanya,
>
> On 15/07/20 06:24, Sowjanya Komatineni wrote:
>> This patch adds IMX274 optional external clock input and voltage
>> supplies to device tree bindings.
>>
>> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
>> ---
>>   Documentation/devicetree/bindings/media/i2c/imx274.txt | 5 +++++
>>   1 file changed, 5 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/media/i2c/imx274.txt b/Documentation/devicetree/bindings/media/i2c/imx274.txt
>> index 80f2e89..ee427f5 100644
>> --- a/Documentation/devicetree/bindings/media/i2c/imx274.txt
>> +++ b/Documentation/devicetree/bindings/media/i2c/imx274.txt
>> @@ -13,6 +13,11 @@ Required Properties:
>>   
>>   Optional Properties:
>>   - reset-gpios: Sensor reset GPIO
>> +- clocks: Reference to the xclk clock.
>> +- clock-names: Should be "xclk".
> Not sure where the "xclk" name comes from, the datasheet I have calls
> the pin "CKIN". Maybe using the same name as the datasheet is better?
>
> Other than that looks good.

Thanks Luca. Using xclk as its external clock to IMX274.

Datasheet uses it as INCK. Will update in v2 to use "INCK" as referred 
in its datasheet.