22 Mar, 2011

5 commits

  • Pick an unused range of ioctls in Documentation/ioctl/ioctl-number.txt
    and use it for the MEDIA_IOC_* ioctls.

    Signed-off-by: Laurent Pinchart
    Signed-off-by: Mauro Carvalho Chehab

    Laurent Pinchart
     
  • Drivers often need to associate pipeline objects to entities, and to
    take stream state into account when configuring entities and links. The
    pipeline API helps drivers manage that information.

    When starting streaming, drivers call media_entity_pipeline_start(). The
    function marks all entities connected to the given entity through
    enabled links, either directly or indirectly, as streaming. Similarly,
    when stopping the stream, drivers call media_entity_pipeline_stop().

    The media_entity_pipeline_start() function takes a pointer to a media
    pipeline and stores it in every entity in the graph. Drivers should
    embed the media_pipeline structure in higher-level pipeline structures
    and can then access the pipeline through the media_entity structure.

    Link configuration will fail with -EBUSY by default if either end of the
    link is a streaming entity, unless the link is marked with the
    MEDIA_LNK_FL_DYNAMIC flag.

    Signed-off-by: Laurent Pinchart
    Acked-by: Hans Verkuil
    Signed-off-by: Mauro Carvalho Chehab

    Laurent Pinchart
     
  • Create the following ioctl and implement it at the media device level to
    setup links.

    - MEDIA_IOC_SETUP_LINK: Modify the properties of a given link

    The only property that can currently be modified is the ENABLED link
    flag to enable/disable a link. Links marked with the IMMUTABLE link flag
    can not be enabled or disabled.

    Enabling or disabling a link has effects on entities' use count. Those
    changes are automatically propagated through the graph.

    Signed-off-by: Laurent Pinchart
    Signed-off-by: Stanimir Varbanov
    Signed-off-by: Sakari Ailus
    Acked-by: Hans Verkuil
    Signed-off-by: Mauro Carvalho Chehab

    Laurent Pinchart
     
  • Create the following two ioctls and implement them at the media device
    level to enumerate entities, pads and links.

    - MEDIA_IOC_ENUM_ENTITIES: Enumerate entities and their properties
    - MEDIA_IOC_ENUM_LINKS: Enumerate all pads and links for a given entity

    Entity IDs can be non-contiguous. Userspace applications should
    enumerate entities using the MEDIA_ENT_ID_FLAG_NEXT flag. When the flag
    is set in the entity ID, the MEDIA_IOC_ENUM_ENTITIES will return the
    next entity with an ID bigger than the requested one.

    Only forward links that originate at one of the entity's source pads are
    returned during the enumeration process.

    Signed-off-by: Laurent Pinchart
    Signed-off-by: Sakari Ailus
    Acked-by: Hans Verkuil
    Signed-off-by: Mauro Carvalho Chehab

    Laurent Pinchart
     
  • Create the following ioctl and implement it at the media device level to
    query device information.

    - MEDIA_IOC_DEVICE_INFO: Query media device information

    The ioctl and its data structure are defined in the new kernel header
    linux/media.h available to userspace applications.

    Signed-off-by: Laurent Pinchart
    Acked-by: Hans Verkuil
    Signed-off-by: Mauro Carvalho Chehab

    Laurent Pinchart