Re: [PATCH 2/3] media: videodev2.h: clarify v4l2_pix_format_mplane.sizeimage docs when to set to zero

[Sakari Ailus]

Hi Helen,

Thanks for the patch.

On Thu, Jan 14, 2021 at 03:01:48PM -0300, Helen Koike wrote:
> sizeimage field should be set to zero for unused planes, even when
> v4l2_pix_format_mplane.num_planes is smaller then the index of planes.
> 
> Signed-off-by: Helen Koike <helen.koike@xxxxxxxxxxxxx>
> 
> ---
> 
> I caught this with v4l2-compliance, which throws an error if we dirty
> planes, even if invalid, so I would like to make it clear in the docs.

Would it be possible to do this in the framework instead?

> ---
>  include/uapi/linux/videodev2.h | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
> index 79dbde3bcf8d..d9b7c9177605 100644
> --- a/include/uapi/linux/videodev2.h
> +++ b/include/uapi/linux/videodev2.h
> @@ -2227,6 +2227,7 @@ struct v4l2_mpeg_vbi_fmt_ivtv {
>   * struct v4l2_plane_pix_format - additional, per-plane format definition
>   * @sizeimage:		maximum size in bytes required for data, for which
>   *			this plane will be used
> + *			Drivers should be set it zero for unused planes.
>   * @bytesperline:	distance in bytes between the leftmost pixels in two
>   *			adjacent lines
>   */

-- 
Kind regards,

Sakari Ailus