[media] media: fsl-viu: fix support for streaming with mmap method

Streaming using mmap didn't work in the VIU driver. We need to
start/stop DMA in streamon/streamoff and free the buffers on
release. Add appropriate driver extension now.
Signed-off-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/fsl-viu.c

@@ -915,6 +915,8 @@ static int vidioc_streamon(struct file *file, void *priv, enum v4l2_buf_type i)
 	if (fh->type != i)
 		return -EINVAL;
 
+	viu_start_dma(fh->dev);
+
 	return videobuf_streamon(&fh->vb_vidq);
 }
 
@@ -927,6 +929,8 @@ static int vidioc_streamoff(struct file *file, void *priv, enum v4l2_buf_type i)
 	if (fh->type != i)
 		return -EINVAL;
 
+	viu_stop_dma(fh->dev);
+
 	return videobuf_streamoff(&fh->vb_vidq);
 }
 
@@ -1331,6 +1335,7 @@ static int viu_release(struct file *file)
 
 	viu_stop_dma(dev);
 	videobuf_stop(&fh->vb_vidq);
+	videobuf_mmap_free(&fh->vb_vidq);
 
 	kfree(fh);