Re: [PATCH v2 4/6] media: i2c: imx335: Enable regulator supplies

[Sakari Ailus <sakari.ailus@linux.intel.com>]

Hi Kieran,

Thanks for the set.

On Wed, Nov 01, 2023 at 01:13:52PM +0000, Kieran Bingham wrote:
> Provide support for enabling and disabling regulator supplies to control
> power to the camera sensor.
> 
> While updating the power on function, document that a sleep is
> represented as 'T4' in the datasheet power on sequence.
> 
> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
> 
> ---
> 
> v2:
>  - document 'supplies' member variable
>  - disable regulators in error path
>  - Remove 'unhelpful' comments
> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
> ---
>  drivers/media/i2c/imx335.c | 38 ++++++++++++++++++++++++++++++++++++--
>  1 file changed, 36 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/media/i2c/imx335.c b/drivers/media/i2c/imx335.c
> index 31c612c6bdd8..f17ce40b9c77 100644
> --- a/drivers/media/i2c/imx335.c
> +++ b/drivers/media/i2c/imx335.c
> @@ -75,6 +75,14 @@ struct imx335_reg_list {
>  	const struct imx335_reg *regs;
>  };
>  
> +static const char * const imx335_supply_name[] = {
> +	"avdd", /* Analog (2.9V) supply */
> +	"ovdd", /* Digital I/O (1.8V) supply */
> +	"dvdd", /* Digital Core (1.2V) supply */
> +};
> +
> +#define IMX335_NUM_SUPPLIES ARRAY_SIZE(imx335_supply_name)

Please use plain ARRAY_SIZE() where you needed this.

> +
>  /**
>   * struct imx335_mode - imx335 sensor mode structure
>   * @width: Frame width
> @@ -108,6 +116,7 @@ struct imx335_mode {
>   * @sd: V4L2 sub-device
>   * @pad: Media pad. Only one pad supported
>   * @reset_gpio: Sensor reset gpio
> + * @supplies: Regulator supplies to handle power control
>   * @inclk: Sensor input clock
>   * @ctrl_handler: V4L2 control handler
>   * @link_freq_ctrl: Pointer to link frequency control
> @@ -126,6 +135,8 @@ struct imx335 {
>  	struct v4l2_subdev sd;
>  	struct media_pad pad;
>  	struct gpio_desc *reset_gpio;
> +	struct regulator_bulk_data supplies[IMX335_NUM_SUPPLIES];
> +
>  	struct clk *inclk;
>  	struct v4l2_ctrl_handler ctrl_handler;
>  	struct v4l2_ctrl *link_freq_ctrl;
> @@ -781,6 +792,17 @@ static int imx335_parse_hw_config(struct imx335 *imx335)
>  		return PTR_ERR(imx335->reset_gpio);
>  	}
>  
> +	for (i = 0; i < IMX335_NUM_SUPPLIES; i++)
> +		imx335->supplies[i].supply = imx335_supply_name[i];
> +
> +	ret = devm_regulator_bulk_get(imx335->dev,
> +				      IMX335_NUM_SUPPLIES,
> +				      imx335->supplies);
> +	if (ret) {
> +		dev_err(imx335->dev, "Failed to get regulators\n");
> +		return ret;
> +	}
> +
>  	/* Get sensor input clock */
>  	imx335->inclk = devm_clk_get(imx335->dev, NULL);
>  	if (IS_ERR(imx335->inclk)) {
> @@ -863,6 +885,17 @@ static int imx335_power_on(struct device *dev)
>  	struct imx335 *imx335 = to_imx335(sd);
>  	int ret;
>  
> +	ret = regulator_bulk_enable(IMX335_NUM_SUPPLIES,
> +				    imx335->supplies);
> +	if (ret) {
> +		dev_err(dev, "%s: failed to enable regulators\n",
> +			__func__);
> +		return ret;
> +	}
> +
> +	usleep_range(500, 550); /* Tlow */
> +
> +	/* Set XCLR */
>  	gpiod_set_value_cansleep(imx335->reset_gpio, 1);
>  
>  	ret = clk_prepare_enable(imx335->inclk);
> @@ -871,12 +904,13 @@ static int imx335_power_on(struct device *dev)
>  		goto error_reset;
>  	}
>  
> -	usleep_range(20, 22);
> +	usleep_range(20, 22); /* T4 */
>  
>  	return 0;
>  
>  error_reset:
>  	gpiod_set_value_cansleep(imx335->reset_gpio, 0);
> +	regulator_bulk_disable(IMX335_NUM_SUPPLIES, imx335->supplies);
>  
>  	return ret;
>  }
> @@ -893,8 +927,8 @@ static int imx335_power_off(struct device *dev)
>  	struct imx335 *imx335 = to_imx335(sd);
>  
>  	gpiod_set_value_cansleep(imx335->reset_gpio, 0);
> -
>  	clk_disable_unprepare(imx335->inclk);
> +	regulator_bulk_disable(IMX335_NUM_SUPPLIES, imx335->supplies);
>  
>  	return 0;
>  }

-- 
Regards,

Sakari Ailus