Em Mon, 16 Apr 2018 15:21:16 +0200
Hans Verkuil <hverkuil@xxxxxxxxx> escreveu:
> From: Hans Verkuil <hansverk@xxxxxxxxx>
>
> This adds support for 'proper' functions to the existing API.
> This information was before only available through the new v2
> API, with this change it's available to both.
>
> Yes, the plan is to allow entities to expose multiple functions for
> multi-function devices, but we do not support it anywhere so this
> is still vaporware.
I'm not convinced about that. I would, instead, just keep it as-is
and be sure that applications stop use the legacy calls.
>
> Signed-off-by: Hans Verkuil <hansverk@xxxxxxxxx>
> ---
> drivers/media/media-device.c | 1 +
> include/uapi/linux/media.h | 7 ++++++-
> 2 files changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/media/media-device.c b/drivers/media/media-device.c
> index 7c3ab37c258a..dca1e5a3e0f9 100644
> --- a/drivers/media/media-device.c
> +++ b/drivers/media/media-device.c
> @@ -115,6 +115,7 @@ static long media_device_enum_entities(struct media_device *mdev,
> if (ent->name)
> strlcpy(entd->name, ent->name, sizeof(entd->name));
> entd->type = ent->function;
> + entd->function = ent->function;
> entd->revision = 0; /* Unused */
I got confused here, until I went to the code and noticed that
entd->type is actually touched after this.
If we're willing to do that, you should add a comment there explaining
why we need to pass both type and function to userspace.
> entd->flags = ent->flags;
> entd->group_id = 0; /* Unused */
> diff --git a/include/uapi/linux/media.h b/include/uapi/linux/media.h
> index 86c7dcc9cba3..ac08acffdb65 100644
> --- a/include/uapi/linux/media.h
> +++ b/include/uapi/linux/media.h
> @@ -146,6 +146,10 @@ struct media_device_info {
> /* OR with the entity id value to find the next entity */
> #define MEDIA_ENT_ID_FLAG_NEXT (1 << 31)
>
> +/* Appeared in 4.18.0 */
> +#define MEDIA_ENTITY_DESC_HAS_FUNCTION(media_version) \
> + ((media_version) >= 0x00041200)
> +
> struct media_entity_desc {
> __u32 id;
> char name[32];
> @@ -155,8 +159,9 @@ struct media_entity_desc {
> __u32 group_id;
> __u16 pads;
> __u16 links;
> + __u32 function;
>
> - __u32 reserved[4];
> + __u32 reserved[3];
>
> union {
> /* Node specifications */
Thanks,
Mauro
