gspca-core: Fix buffers staying in queued state after a stream_off

commit af05ef01 upstream.

This fixes a regression introduced by commit f7059eaa and should be
backported to all supported stable kernels which have this commit.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Tested-by: Antonio Ospite <ospite@studenti.unina.it>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

drivers/media/video/gspca/gspca.c

@@ -1697,7 +1697,7 @@ static int vidioc_streamoff(struct file *file, void *priv,
 				enum v4l2_buf_type buf_type)
 {
 	struct gspca_dev *gspca_dev = priv;
-	int ret;
+	int i, ret;
 
 	if (buf_type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
 		return -EINVAL;
@@ -1728,6 +1728,8 @@ static int vidioc_streamoff(struct file *file, void *priv,
 	wake_up_interruptible(&gspca_dev->wq);
 
 	/* empty the transfer queues */
+	for (i = 0; i < gspca_dev->nframes; i++)
+		gspca_dev->frame[i].v4l2_buf.flags &= ~BUF_ALL_FLAGS;
 	atomic_set(&gspca_dev->fr_q, 0);
 	atomic_set(&gspca_dev->fr_i, 0);
 	gspca_dev->fr_o = 0;