V4L/DVB: videobuf: add ext_lock argument to the queue init functions

Add an ext_lock argument to the videobuf init functions. This allows
drivers to pass the vdev->lock pointer (or any other externally held lock)
to videobuf. For now all drivers just pass NULL.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/include/media/videobuf-dma-contig.h b/include/media/videobuf-dma-contig.h
index ebaa9bc..f0ed825 100644
--- a/include/media/videobuf-dma-contig.h
+++ b/include/media/videobuf-dma-contig.h
@@ -23,7 +23,8 @@
 				    enum v4l2_buf_type type,
 				    enum v4l2_field field,
 				    unsigned int msize,
-				    void *priv);
+				    void *priv,
+				    struct mutex *ext_lock);
 
 dma_addr_t videobuf_to_dma_contig(struct videobuf_buffer *buf);
 void videobuf_dma_contig_free(struct videobuf_queue *q,