[PATCH v7 1/6] [media] vb2: add is_unordered callback for drivers

From: Gustavo Padovan
Date: Wed Jan 10 2018 - 11:10:07 EST


From: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxx>

Explicit synchronization benefits a lot from ordered queues, they fit
better in a pipeline with DRM for example so create a opt-in way for
drivers notify videobuf2 that the queue is unordered.

Drivers don't need implement it if the queue is ordered.

Signed-off-by: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxx>
---
include/media/videobuf2-core.h | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h
index f3ee4c7c2fb3..583cdc06de79 100644
--- a/include/media/videobuf2-core.h
+++ b/include/media/videobuf2-core.h
@@ -370,6 +370,9 @@ struct vb2_buffer {
* callback by calling vb2_buffer_done() with either
* %VB2_BUF_STATE_DONE or %VB2_BUF_STATE_ERROR; may use
* vb2_wait_for_all_buffers() function
+ * @is_unordered: tell if the queue format is unordered. The default is
+ * assumed to be ordered and this function only needs to
+ * be implemented for unordered queues.
* @buf_queue: passes buffer vb to the driver; driver may start
* hardware operation on this buffer; driver should give
* the buffer back by calling vb2_buffer_done() function;
@@ -393,6 +396,7 @@ struct vb2_ops {

int (*start_streaming)(struct vb2_queue *q, unsigned int count);
void (*stop_streaming)(struct vb2_queue *q);
+ int (*is_unordered)(struct vb2_queue *q);

void (*buf_queue)(struct vb2_buffer *vb);
};
@@ -566,6 +570,7 @@ struct vb2_queue {
u32 cnt_wait_finish;
u32 cnt_start_streaming;
u32 cnt_stop_streaming;
+ u32 cnt_is_unordered;
#endif
};

--
2.14.3