media: omap3isp: add missing wait_prepare/finish ops

Without these ops the v4l2-compliance blocking wait test will fail.
These ops are required to ensure that when VIDIOC_DQBUF has to
wait for buffers to arrive, the queue lock is correctly released
and retaken. Otherwise the wait for a buffer would block all other
queue ioctls.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/platform/ti/omap3isp/ispvideo.c

@@ -480,11 +480,29 @@ static int isp_video_start_streaming(struct vb2_queue *queue,
 	return 0;
 }
 
+static void omap3isp_wait_prepare(struct vb2_queue *vq)
+{
+	struct isp_video_fh *vfh = vb2_get_drv_priv(vq);
+	struct isp_video *video = vfh->video;
+
+	mutex_unlock(&video->queue_lock);
+}
+
+static void omap3isp_wait_finish(struct vb2_queue *vq)
+{
+	struct isp_video_fh *vfh = vb2_get_drv_priv(vq);
+	struct isp_video *video = vfh->video;
+
+	mutex_lock(&video->queue_lock);
+}
+
 static const struct vb2_ops isp_video_queue_ops = {
 	.queue_setup = isp_video_queue_setup,
 	.buf_prepare = isp_video_buffer_prepare,
 	.buf_queue = isp_video_buffer_queue,
 	.start_streaming = isp_video_start_streaming,
+	.wait_prepare = omap3isp_wait_prepare,
+	.wait_finish = omap3isp_wait_finish,
 };
 
 /*