diff --git a/include/media/v4l2-ioctl.h b/include/media/v4l2-ioctl.h
index 3eef4de..babbe09 100644
--- a/include/media/v4l2-ioctl.h
+++ b/include/media/v4l2-ioctl.h
@@ -167,7 +167,7 @@
 	int (*vidioc_g_audio)          (struct file *file, void *fh,
 					struct v4l2_audio *a);
 	int (*vidioc_s_audio)          (struct file *file, void *fh,
-					struct v4l2_audio *a);
+					const struct v4l2_audio *a);
 
 	/* Audio out ioctls */
 	int (*vidioc_enumaudout)       (struct file *file, void *fh,