On 05/05/2023 23:52, Sakari Ailus wrote:
> Internal source pads will be used as routing endpoints in V4L2
> [GS]_ROUTING IOCTLs, to indicate that the stream begins in the entity.
>
> Also prevent creating links to pads that have been flagged as internal.
>
> Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> ---
> .../userspace-api/media/mediactl/media-types.rst | 7 +++++++
> drivers/media/mc/mc-entity.c | 8 +++++++-
> include/uapi/linux/media.h | 1 +
> 3 files changed, 15 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/userspace-api/media/mediactl/media-types.rst b/Documentation/userspace-api/media/mediactl/media-types.rst
> index 0ffeece1e0c8..c724139ad46c 100644
> --- a/Documentation/userspace-api/media/mediactl/media-types.rst
> +++ b/Documentation/userspace-api/media/mediactl/media-types.rst
> @@ -361,6 +361,7 @@ Types and flags used to represent the media graph elements
> .. _MEDIA-PAD-FL-SINK:
> .. _MEDIA-PAD-FL-SOURCE:
> .. _MEDIA-PAD-FL-MUST-CONNECT:
> +.. _MEDIA-PAD-FL-INTERNAL-SOURCE:
>
> .. flat-table:: Media pad flags
> :header-rows: 0
> @@ -382,6 +383,12 @@ Types and flags used to represent the media graph elements
> when this flag isn't set; the absence of the flag doesn't imply
> there is none.
>
> + * - ``MEDIA_PAD_FL_INTERNAL_SOURCE``
> + - This flag indicates an internal pad that has no external
'internal pad' or 'internal source pad'?
> + connections. Such a pad may not be connected with a link. The internal
> + flag indicates that the stream either starts or ends in the
> + entity.
This sentence makes no sense. The flag is for a pad, but then this sentence
talks about streams and entities and doesn't relate that to the pad. Also,
the flag is INTERNAL_SOURCE, and reading 'stream ends' suggests that it
should be INTERNAL_SINK in that case.
I think this needs to be more elaborate and ideally add some examples
of the use-case(s) (or refer to an example elsewhere).
For a given pad, the INTERNAL_SOURCE flag may not be set if
> + either SINK or SOURCE flags is set.
>
> One and only one of ``MEDIA_PAD_FL_SINK`` and ``MEDIA_PAD_FL_SOURCE``
and 'MEDIA_PAD_FL_INTERNAL_SOURCE' as well?
> must be set for every pad.
> diff --git a/drivers/media/mc/mc-entity.c b/drivers/media/mc/mc-entity.c
> index ef34ddd715c9..ed99160a2487 100644
> --- a/drivers/media/mc/mc-entity.c
> +++ b/drivers/media/mc/mc-entity.c
> @@ -1062,7 +1062,8 @@ int media_get_pad_index(struct media_entity *entity, u32 pad_type,
>
> for (i = 0; i < entity->num_pads; i++) {
> if ((entity->pads[i].flags &
> - (MEDIA_PAD_FL_SINK | MEDIA_PAD_FL_SOURCE)) != pad_type)
> + (MEDIA_PAD_FL_SINK | MEDIA_PAD_FL_SOURCE |
> + MEDIA_PAD_FL_INTERNAL_SOURCE)) != pad_type)
> continue;
>
> if (entity->pads[i].sig_type == sig_type)
> @@ -1087,6 +1088,11 @@ media_create_pad_link(struct media_entity *source, u16 source_pad,
> return -EINVAL;
> if (WARN_ON(!(sink->pads[sink_pad].flags & MEDIA_PAD_FL_SINK)))
> return -EINVAL;
> + if (WARN_ON(sink->pads[sink_pad].flags &
> + MEDIA_PAD_FL_INTERNAL_SOURCE) ||
> + WARN_ON(source->pads[source_pad].flags &
> + MEDIA_PAD_FL_INTERNAL_SOURCE))
> + return -EINVAL;
>
> link = media_add_link(&source->links);
> if (link == NULL)
> diff --git a/include/uapi/linux/media.h b/include/uapi/linux/media.h
> index edb8dfef9eba..0e2577e8b425 100644
> --- a/include/uapi/linux/media.h
> +++ b/include/uapi/linux/media.h
> @@ -208,6 +208,7 @@ struct media_entity_desc {
> #define MEDIA_PAD_FL_SINK (1U << 0)
> #define MEDIA_PAD_FL_SOURCE (1U << 1)
> #define MEDIA_PAD_FL_MUST_CONNECT (1U << 2)
> +#define MEDIA_PAD_FL_INTERNAL_SOURCE (1U << 3)
>
> struct media_pad_desc {
> __u32 entity; /* entity ID */
Regards,
Hans
