Re: [v8 01/14] media: Add RPP_X1_PARAMS and RPP_X1_STATS meta formats

[Jacopo Mondi]

Hi Niklas

On Mon, May 04, 2026 at 03:05:43AM +0200, Niklas Söderlund wrote:
> From: Jai Luthra <jai.luthra+renesas@xxxxxxxxxxxxxxxx>
>
> Register V4L2 metadata fourcc codes for the Dreamchip RPP-X1 ISP
> parameters and statistics buffers. These formats are used by the driver
> to exchange ISP configuration and 3A statistics with userspace through
> the extensible parameters framework.
>
> Signed-off-by: Jai Luthra <jai.luthra+renesas@xxxxxxxxxxxxxxxx>
> Reviewed-by: Jacopo Mondi <jacopo.mondi@xxxxxxxxxxxxxxxx>
> Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>

As pointed out in the review of the previous version you need to add
documentation for the formats in
Documentation/userspace-api/media/v4l/metafmt-dcc-rppx1.rst (or
similar)

> ---
>  drivers/media/v4l2-core/v4l2-ioctl.c | 2 ++
>  include/uapi/linux/videodev2.h       | 4 ++++
>  2 files changed, 6 insertions(+)
>
> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
> index a2b650f4ec3c..cd3f4a86e27f 100644
> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
> @@ -1471,6 +1471,8 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt)
>  	case V4L2_META_FMT_C3ISP_STATS:		descr = "Amlogic C3 ISP Statistics"; break;
>  	case V4L2_META_FMT_MALI_C55_PARAMS:	descr = "ARM Mali-C55 ISP Parameters"; break;
>  	case V4L2_META_FMT_MALI_C55_STATS:	descr = "ARM Mali-C55 ISP 3A Statistics"; break;
> +	case V4L2_META_FMT_RPP_X1_PARAMS:	descr = "Dreamchip RPP-X1 ISP Parameters"; break;
> +	case V4L2_META_FMT_RPP_X1_STATS:	descr = "Dreamchip RPP-X1 ISP Statistics"; break;
>  	case V4L2_PIX_FMT_NV12_8L128:	descr = "NV12 (8x128 Linear)"; break;
>  	case V4L2_PIX_FMT_NV12M_8L128:	descr = "NV12M (8x128 Linear)"; break;
>  	case V4L2_PIX_FMT_NV12_10BE_8L128:	descr = "10-bit NV12 (8x128 Linear, BE)"; break;
> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
> index eda4492e40dc..1f78b5378b3b 100644
> --- a/include/uapi/linux/videodev2.h
> +++ b/include/uapi/linux/videodev2.h
> @@ -889,6 +889,10 @@ struct v4l2_pix_format {
>  #define V4L2_META_FMT_MALI_C55_PARAMS	v4l2_fourcc('C', '5', '5', 'P') /* ARM Mali-C55 Parameters */
>  #define V4L2_META_FMT_MALI_C55_STATS	v4l2_fourcc('C', '5', '5', 'S') /* ARM Mali-C55 3A Statistics */
>
> +/* Vendor specific - used for Dreamchip RPP-X1 ISP */
> +#define V4L2_META_FMT_RPP_X1_PARAMS	v4l2_fourcc('D', 'R', '1', 'P') /* Dreamchip RPP-X1 Parameters */
> +#define V4L2_META_FMT_RPP_X1_STATS	v4l2_fourcc('D', 'R', '1', 'S') /* Dreamchip RPP-X1 Statistics */
> +
>  #ifdef __KERNEL__
>  /*
>   * Line-based metadata formats. Remember to update v4l_fill_fmtdesc() when
> --
> 2.54.0
>