[RFC,v4,08/17,media] vb2: add 'ordered_in_driver' property to queues
Commit Message
From: Gustavo Padovan <gustavo.padovan@collabora.com>
For explicit synchronization (and soon for HAL3/Request API) we need
the v4l2-driver to guarantee the ordering in which the buffers were queued
by userspace. This is already true for many drivers, but we never needed
to say it.
v2: rename property to 'ordered_in_driver' to avoid confusion
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.com>
---
include/media/videobuf2-core.h | 6 ++++++
1 file changed, 6 insertions(+)
Comments
On 10/20/2017 11:50 PM, Gustavo Padovan wrote:
> From: Gustavo Padovan <gustavo.padovan@collabora.com>
>
> For explicit synchronization (and soon for HAL3/Request API) we need
> the v4l2-driver to guarantee the ordering in which the buffers were queued
> by userspace. This is already true for many drivers, but we never needed
> to say it.
>
> v2: rename property to 'ordered_in_driver' to avoid confusion
>
> Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.com>
> ---
> include/media/videobuf2-core.h | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h
> index 96af4eb49e52..6dd3f0181107 100644
> --- a/include/media/videobuf2-core.h
> +++ b/include/media/videobuf2-core.h
> @@ -500,6 +500,11 @@ struct vb2_buf_ops {
> * @last_buffer_dequeued: used in poll() and DQBUF to immediately return if the
> * last decoded buffer was already dequeued. Set for capture queues
> * when a buffer with the V4L2_BUF_FLAG_LAST is dequeued.
> + * @ordered_in_driver: if the driver can guarantee that the queue will be
> + * ordered or not, i.e., the buffers are queued to the driver in
> + * the same order they are dequeued from the driver. The default
I'd swap the words 'queued' and 'dequeued'. It's more logical that way.
Regards,
Hans
> + * is not ordered unless the driver sets this flag. As of now it
> + * is mandatory for using explicit fences.
> * @fileio: file io emulator internal data, used only if emulator is active
> * @threadio: thread io internal data, used only if thread is active
> */
> @@ -552,6 +557,7 @@ struct vb2_queue {
> unsigned int is_output:1;
> unsigned int copy_timestamp:1;
> unsigned int last_buffer_dequeued:1;
> + unsigned int ordered_in_driver:1;
>
> struct vb2_fileio_data *fileio;
> struct vb2_threadio_data *threadio;
>
@@ -500,6 +500,11 @@ struct vb2_buf_ops {
* @last_buffer_dequeued: used in poll() and DQBUF to immediately return if the
* last decoded buffer was already dequeued. Set for capture queues
* when a buffer with the V4L2_BUF_FLAG_LAST is dequeued.
+ * @ordered_in_driver: if the driver can guarantee that the queue will be
+ * ordered or not, i.e., the buffers are queued to the driver in
+ * the same order they are dequeued from the driver. The default
+ * is not ordered unless the driver sets this flag. As of now it
+ * is mandatory for using explicit fences.
* @fileio: file io emulator internal data, used only if emulator is active
* @threadio: thread io internal data, used only if thread is active
*/
@@ -552,6 +557,7 @@ struct vb2_queue {
unsigned int is_output:1;
unsigned int copy_timestamp:1;
unsigned int last_buffer_dequeued:1;
+ unsigned int ordered_in_driver:1;
struct vb2_fileio_data *fileio;
struct vb2_threadio_data *threadio;