On 08/08/2023 09:55, 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>
> ---
> Documentation/userspace-api/media/glossary.rst | 6 ++++++
> Documentation/userspace-api/media/mediactl/media-types.rst | 6 ++++++
> drivers/media/mc/mc-entity.c | 6 +++++-
> include/uapi/linux/media.h | 1 +
> 4 files changed, 18 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/userspace-api/media/glossary.rst b/Documentation/userspace-api/media/glossary.rst
> index 96a360edbf3b..f7b99a4527c7 100644
> --- a/Documentation/userspace-api/media/glossary.rst
> +++ b/Documentation/userspace-api/media/glossary.rst
> @@ -173,6 +173,12 @@ Glossary
> An integrated circuit that integrates all components of a computer
> or other electronic systems.
>
> +_media-glossary-stream:
> + Stream
> + A distinct flow of data (image data or metadata) over a media pipeline
> + from source to sink. A source may be e.g. an image sensor and a sink
> + e.g. a memory buffer.
> +
> V4L2 API
> **V4L2 userspace API**
>
> diff --git a/Documentation/userspace-api/media/mediactl/media-types.rst b/Documentation/userspace-api/media/mediactl/media-types.rst
> index 0ffeece1e0c8..28941da27790 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:
>
> .. flat-table:: Media pad flags
> :header-rows: 0
> @@ -382,6 +383,11 @@ 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``
> + - The internal flag indicates an internal pad that has no external
> + connections. Such a pad shall not be connected with a link. The
> + internal flag indicates that the :ref:``stream
> + <media-glossary-stream>`` either starts or ends in the entity.
>
> One and only one of ``MEDIA_PAD_FL_SINK`` and ``MEDIA_PAD_FL_SOURCE``
> must be set for every pad.
> diff --git a/drivers/media/mc/mc-entity.c b/drivers/media/mc/mc-entity.c
> index 4991281dcccc..03a9e0b8ebab 100644
> --- a/drivers/media/mc/mc-entity.c
> +++ b/drivers/media/mc/mc-entity.c
> @@ -1071,7 +1071,8 @@ 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)) != pad_type)
> continue;
>
> if (entity->pads[i].sig_type == sig_type)
> @@ -1094,6 +1095,9 @@ media_create_pad_link(struct media_entity *source, u16 source_pad,
> return -EINVAL;
> if (WARN_ON(!(source->pads[source_pad].flags & MEDIA_PAD_FL_SOURCE)))
> return -EINVAL;
> + if (WARN_ON(source->pads[source_pad].flags & MEDIA_PAD_FL_SOURCE &&
> + source->pads[source_pad].flags & MEDIA_PAD_FL_INTERNAL))
Even though this code is correct, I prefer to have () around the 'x & y' parts.
It avoids confusion for the reader.
Up to you, though.
Regards,
Hans
> + return -EINVAL;
> if (WARN_ON(!(sink->pads[sink_pad].flags & MEDIA_PAD_FL_SINK)))
> return -EINVAL;
>
> diff --git a/include/uapi/linux/media.h b/include/uapi/linux/media.h
> index 1c80b1d6bbaf..80cfd12a43fc 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 (1U << 3)
>
> struct media_pad_desc {
> __u32 entity; /* entity ID */
