Re: [PATCH 1/5] media: media.h: Add new media link type

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Daniel,

Thank you for the patch.

On Mon, Dec 13, 2021 at 11:28:45PM +0000, Daniel Scally wrote:
> To describe in the kernel the connection between devices and their
> supporting peripherals (for example, a camera sensor and the vcm
> driving the focusing lens for it), add a new type of media link
> to introduce the concept of these ancillary links.
> 
> Signed-off-by: Daniel Scally <djrscally@gmail.com>
> ---
> changes since the rfc:
> 
> 	- Split out into its own patch (mostly so it can be followed by patch
> 	#3, which corrects some media-core code that is otherwise broken by the
> 	new links)
> 
>  include/uapi/linux/media.h | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/include/uapi/linux/media.h b/include/uapi/linux/media.h
> index 200fa8462b90..afbae7213d35 100644
> --- a/include/uapi/linux/media.h
> +++ b/include/uapi/linux/media.h
> @@ -226,6 +226,7 @@ struct media_pad_desc {
>  #define MEDIA_LNK_FL_LINK_TYPE			(0xf << 28)
>  #  define MEDIA_LNK_FL_DATA_LINK		(0 << 28)
>  #  define MEDIA_LNK_FL_INTERFACE_LINK		(1 << 28)
> +#  define MEDIA_LNK_FL_ANCILLARY_LINK		(2 << 28)

This needs documentation in
Documentation/userspace-api/media/mediactl/media-types.rst and in
media-controller-model.rst. The latter should probably be a bit more
detailed to explain the use cases with at least one example.

>  
>  struct media_link_desc {
>  	struct media_pad_desc source;

-- 
Regards,

Laurent Pinchart