media: vb2: don't call __vb2_queue_cancel if vb2_start_streaming failed

vb2_start_streaming() already rolls back the buffers, so there is no
need to call __vb2_queue_cancel(). Especially since __vb2_queue_cancel()
does too much, such as zeroing the q->queued_count value, causing vb2
to think that no buffers have been queued.

It appears that this call to __vb2_queue_cancel() is a left-over from
before commit b3379c6201bb3.

Fixes: b3379c6201bb3 ('vb2: only call start_streaming if sufficient buffers are queued')

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Cc: <stable@vger.kernel.org>      # for v4.16 and up
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c
index 975ff56..e006698 100644 (file)
--- a/drivers/media/common/videobuf2/videobuf2-core.c
+++ b/drivers/media/common/videobuf2/videobuf2-core.c
@@ -1940,10 +1940,8 @@ int vb2_core_streamon(struct vb2_queue *q, unsigned int type)
                if (ret)
                        return ret;
                ret = vb2_start_streaming(q);
-               if (ret) {
-                       __vb2_queue_cancel(q);
+               if (ret)
                        return ret;
-               }
        }
 
        q->streaming = 1;