Subject: Re: [PATCH] media: i2c: imx274: implement enum_mbus_code
To:     Eugen Hristev <eugen.hristev@microchip.com>,
        leonl@leopardimaging.com, linux-media@vger.kernel.org
Cc:     skomatineni@nvidia.com, sakari.ailus@linux.intel.com,
        linux-kernel@vger.kernel.org
References: <20211118154009.307430-1-eugen.hristev@microchip.com>
From:   Luca Ceresoli <luca@lucaceresoli.net>
Message-ID: <fa26e991-9228-7ed7-833a-b296e6b32afc@lucaceresoli.net>
Date:   Thu, 18 Nov 2021 18:11:35 +0100
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Hi Eugen,

On 18/11/21 16:40, Eugen Hristev wrote:
> Current driver supports only SRGGB 10 bit RAW bayer format.
> Add the enum_mbus_code implementation to report this format supported.
> 
>  # v4l2-ctl -d /dev/v4l-subdev3 --list-subdev-mbus-codes
> ioctl: VIDIOC_SUBDEV_ENUM_MBUS_CODE (pad=0)
>         0x300f: MEDIA_BUS_FMT_SRGGB10_1X10
>  #
> 
> Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>

Generally OK, but I have a few minor comments.

> ---
>  drivers/media/i2c/imx274.c | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
> 
> diff --git a/drivers/media/i2c/imx274.c b/drivers/media/i2c/imx274.c
> index 2e804e3b70c4..25a4ef8f6187 100644
> --- a/drivers/media/i2c/imx274.c
> +++ b/drivers/media/i2c/imx274.c
> @@ -1909,7 +1909,21 @@ static int imx274_set_frame_interval(struct stimx274 *priv,
>  	return err;
>  }
>  
> +static int imx274_enum_mbus_code(struct v4l2_subdev *sd,
> +				 struct v4l2_subdev_state *sd_state,
> +				 struct v4l2_subdev_mbus_code_enum *code)
> +{
> +	if (code->index > 0)
> +		return -EINVAL;

Many driver do check code->pad too, so you might want to do

	if (code->pad > 0 || code->index > 0)
		return -EINVAL;

However I don't think it is strictly necessary, thus

> +
> +	/* only supported format in the driver is Raw 10 bits SRGGB */
> +	code->code = MEDIA_BUS_FMT_SRGGB10_1X10;

Maybe better:

  code->code =  to_imx274(sd)->format.code

just as a little guard for future format changes.

With or without these I'm OK anyway with the patch, so:

Reviewed-by: Luca Ceresoli <luca@lucaceresoli.net>

-- 
Luca