[PATCH v3 09/15] [media] v4l: add support to BUF_QUEUED event

From: Gustavo Padovan Implement the needed pieces to let userspace subscribe for V4L2_EVENT_BUF_QUEUED events. Videobuf2 will queue the event for the DQEVENT ioctl. v3: - Do not call v4l2 event API from vb2 (Mauro) v2: - Use VIDEO_MAX_FRAME to allocate

[PATCH v3 09/15] [media] v4l: add support to BUF_QUEUED event

From: Gustavo Padovan Implement the needed pieces to let userspace subscribe for V4L2_EVENT_BUF_QUEUED events. Videobuf2 will queue the event for the DQEVENT ioctl. v3: - Do not call v4l2 event API from vb2 (Mauro) v2: - Use VIDEO_MAX_FRAME to allocate room for events at