Re: [PATCH v8.1 03/10] media: i2c: ov6650: Use new [get|set]_mbus_config ops

[Janusz Krzysztofik <jmkrzyszt@gmail.com>]

On Tuesday, July 21, 2020 9:53:17 A.M. CEST Jacopo Mondi wrote:
> Use the new get_mbus_config and set_mbus_config pad operations in place
> of the video operations currently in use.
> 
> Compared to other drivers where the same conversion has been performed,
> ov6650 proved to be a bit more tricky, as the existing g_mbus_config
> implementation did not report the currently applied configuration but
> the set of all possible configuration options.
> 
> Adapt the driver to support the semantic of the two newly introduced
> operations:
> - get_mbus_config reports the current media bus configuration
> - set_mbus_config applies only changes explicitly requested and updates
>   the provided cfg parameter to report what has actually been applied to
>   the hardware.
> 
> Compile-tested only.
> 
> Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>

Acked-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>

Thanks,
Janusz

> ---
> v8 -> v8.1
> 
> - Return error on register write fails in set_mbus_config() as suggested
>   by Janusz.
> 
> ---
>  drivers/media/i2c/ov6650.c | 53 ++++++++++++++++++++++++++------------
>  1 file changed, 37 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/media/i2c/ov6650.c b/drivers/media/i2c/ov6650.c
> index 91906b94f978..48493af81198 100644
> --- a/drivers/media/i2c/ov6650.c
> +++ b/drivers/media/i2c/ov6650.c
> @@ -921,55 +921,74 @@ static const struct v4l2_subdev_core_ops ov6650_core_ops = {
>  };
> 
>  /* Request bus settings on camera side */
> -static int ov6650_g_mbus_config(struct v4l2_subdev *sd,
> -				struct v4l2_mbus_config *cfg)
> +static int ov6650_get_mbus_config(struct v4l2_subdev *sd,
> +				  unsigned int pad,
> +				  struct v4l2_mbus_config *cfg)
>  {
> +	struct i2c_client *client = v4l2_get_subdevdata(sd);
> +	u8 comj, comf;
> +	int ret;
> +
> +	ret = ov6650_reg_read(client, REG_COMJ, &comj);
> +	if (ret)
> +		return ret;
> 
> -	cfg->flags = V4L2_MBUS_MASTER |
> -		V4L2_MBUS_PCLK_SAMPLE_RISING | V4L2_MBUS_PCLK_SAMPLE_FALLING |
> -		V4L2_MBUS_HSYNC_ACTIVE_HIGH | V4L2_MBUS_HSYNC_ACTIVE_LOW |
> -		V4L2_MBUS_VSYNC_ACTIVE_HIGH | V4L2_MBUS_VSYNC_ACTIVE_LOW |
> -		V4L2_MBUS_DATA_ACTIVE_HIGH;
> +	ret = ov6650_reg_read(client, REG_COMF, &comf);
> +	if (ret)
> +		return ret;
> +
> +	cfg->flags = V4L2_MBUS_MASTER | V4L2_MBUS_DATA_ACTIVE_HIGH
> +		   | ((comj & COMJ_VSYNC_HIGH)  ? V4L2_MBUS_VSYNC_ACTIVE_HIGH
> +						: V4L2_MBUS_VSYNC_ACTIVE_LOW)
> +		   | ((comf & COMF_HREF_LOW)    ? V4L2_MBUS_HSYNC_ACTIVE_LOW
> +						: V4L2_MBUS_HSYNC_ACTIVE_HIGH)
> +		   | ((comj & COMJ_PCLK_RISING) ? V4L2_MBUS_PCLK_SAMPLE_RISING
> +						: V4L2_MBUS_PCLK_SAMPLE_FALLING);
>  	cfg->type = V4L2_MBUS_PARALLEL;
> 
>  	return 0;
>  }
> 
>  /* Alter bus settings on camera side */
> -static int ov6650_s_mbus_config(struct v4l2_subdev *sd,
> -				const struct v4l2_mbus_config *cfg)
> +static int ov6650_set_mbus_config(struct v4l2_subdev *sd,
> +				  unsigned int pad,
> +				  struct v4l2_mbus_config *cfg)
>  {
>  	struct i2c_client *client = v4l2_get_subdevdata(sd);
> -	int ret;
> +	int ret = 0;
> 
>  	if (cfg->flags & V4L2_MBUS_PCLK_SAMPLE_RISING)
>  		ret = ov6650_reg_rmw(client, REG_COMJ, COMJ_PCLK_RISING, 0);
> -	else
> +	else if (cfg->flags & V4L2_MBUS_PCLK_SAMPLE_FALLING)
>  		ret = ov6650_reg_rmw(client, REG_COMJ, 0, COMJ_PCLK_RISING);
>  	if (ret)
>  		return ret;
> 
>  	if (cfg->flags & V4L2_MBUS_HSYNC_ACTIVE_LOW)
>  		ret = ov6650_reg_rmw(client, REG_COMF, COMF_HREF_LOW, 0);
> -	else
> +	else if (cfg->flags & V4L2_MBUS_HSYNC_ACTIVE_HIGH)
>  		ret = ov6650_reg_rmw(client, REG_COMF, 0, COMF_HREF_LOW);
>  	if (ret)
>  		return ret;
> 
>  	if (cfg->flags & V4L2_MBUS_VSYNC_ACTIVE_HIGH)
>  		ret = ov6650_reg_rmw(client, REG_COMJ, COMJ_VSYNC_HIGH, 0);
> -	else
> +	else if (cfg->flags & V4L2_MBUS_VSYNC_ACTIVE_LOW)
>  		ret = ov6650_reg_rmw(client, REG_COMJ, 0, COMJ_VSYNC_HIGH);
> +	if (ret)
> +		return ret;
> 
> -	return ret;
> +	/*
> +	 * Update the configuration to report what is actually applied to
> +	 * the hardware.
> +	 */
> +	return ov6650_get_mbus_config(sd, pad, cfg);
>  }
> 
>  static const struct v4l2_subdev_video_ops ov6650_video_ops = {
>  	.s_stream	= ov6650_s_stream,
>  	.g_frame_interval = ov6650_g_frame_interval,
>  	.s_frame_interval = ov6650_s_frame_interval,
> -	.g_mbus_config	= ov6650_g_mbus_config,
> -	.s_mbus_config	= ov6650_s_mbus_config,
>  };
> 
>  static const struct v4l2_subdev_pad_ops ov6650_pad_ops = {
> @@ -978,6 +997,8 @@ static const struct v4l2_subdev_pad_ops ov6650_pad_ops = {
>  	.set_selection	= ov6650_set_selection,
>  	.get_fmt	= ov6650_get_fmt,
>  	.set_fmt	= ov6650_set_fmt,
> +	.get_mbus_config = ov6650_get_mbus_config,
> +	.set_mbus_config = ov6650_set_mbus_config,
>  };
> 
>  static const struct v4l2_subdev_ops ov6650_subdev_ops = {
> --
> 2.27.0
> 
>