[media] media: blackfin: bfin_capture: release buffers in case start_streaming() call back fails

this patch adds support to release the buffer by calling
vb2_buffer_done(), with state marked as VB2_BUF_STATE_QUEUED
if start_streaming() call back fails.
Signed-off-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>
Tested-by: Scott Jiang <scott.jiang.linux@gmail.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/platform/blackfin/bfin_capture.c

@@ -345,6 +345,7 @@ static int bcap_start_streaming(struct vb2_queue *vq, unsigned int count)
 {
 	struct bcap_device *bcap_dev = vb2_get_drv_priv(vq);
 	struct ppi_if *ppi = bcap_dev->ppi;
+	struct bcap_buffer *buf, *tmp;
 	struct ppi_params params;
 	int ret;
 
@@ -352,7 +353,7 @@ static int bcap_start_streaming(struct vb2_queue *vq, unsigned int count)
 	ret = v4l2_subdev_call(bcap_dev->sd, video, s_stream, 1);
 	if (ret && (ret != -ENOIOCTLCMD)) {
 		v4l2_err(&bcap_dev->v4l2_dev, "stream on failed in subdev\n");
-		return ret;
+		goto err;
 	}
 
 	/* set ppi params */
@@ -391,7 +392,7 @@ static int bcap_start_streaming(struct vb2_queue *vq, unsigned int count)
 	if (ret < 0) {
 		v4l2_err(&bcap_dev->v4l2_dev,
 				"Error in setting ppi params\n");
-		return ret;
+		goto err;
 	}
 
 	/* attach ppi DMA irq handler */
@@ -399,12 +400,21 @@ static int bcap_start_streaming(struct vb2_queue *vq, unsigned int count)
 	if (ret < 0) {
 		v4l2_err(&bcap_dev->v4l2_dev,
 				"Error in attaching interrupt handler\n");
-		return ret;
+		goto err;
 	}
 
 	reinit_completion(&bcap_dev->comp);
 	bcap_dev->stop = false;
+
 	return 0;
+
+err:
+	list_for_each_entry_safe(buf, tmp, &bcap_dev->dma_queue, list) {
+		list_del(&buf->list);
+		vb2_buffer_done(&buf->vb, VB2_BUF_STATE_QUEUED);
+	}
+
+	return ret;
 }
 
 static void bcap_stop_streaming(struct vb2_queue *vq)