path: root/drivers/media/v4l2-core
diff options
authorHans Verkuil <hverkuil@xs4all.nl>2015-10-29 03:02:06 -0200
committerMauro Carvalho Chehab <mchehab@osg.samsung.com>2015-11-17 14:35:39 -0200
commit4623e5967448444a4ea1e77beb58898c4af48693 (patch)
tree11729177d95b4acabb0f37c9c50f05daf4fb7699 /drivers/media/v4l2-core
parentf6de9f608504849f3437abe60eeb43932ec5455e (diff)
[media] vb2: fix a regression in poll() behavior for output,streams
In the 3.17 kernel the poll() behavior changed for output streams: as long as not all buffers were queued up poll() would return that userspace can write. This is fine for the write() call, but when using stream I/O this changed the behavior since the expectation was that it would wait for buffers to become available for dequeuing. This patch only enables the check whether you can queue buffers for file I/O only, and skips it for stream I/O. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Cc: <stable@vger.kernel.org> # for v3.17 and up Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Diffstat (limited to 'drivers/media/v4l2-core')
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/media/v4l2-core/videobuf2-v4l2.c b/drivers/media/v4l2-core/videobuf2-v4l2.c
index 27b4b9e7c0c2..502984c724ff 100644
--- a/drivers/media/v4l2-core/videobuf2-v4l2.c
+++ b/drivers/media/v4l2-core/videobuf2-v4l2.c
@@ -822,10 +822,10 @@ unsigned int vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait)
return res | POLLERR;
- * For output streams you can write as long as there are fewer buffers
- * queued than there are buffers available.
+ * For output streams you can call write() as long as there are fewer
+ * buffers queued than there are buffers available.
- if (q->is_output && q->queued_count < q->num_buffers)
+ if (q->is_output && q->fileio && q->queued_count < q->num_buffers)
return res | POLLOUT | POLLWRNORM;
if (list_empty(&q->done_list)) {

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