[media] v4l: omap4iss: Move code out of mutex-protected section

The pad::get_fmt call must be protected by a mutex, but preparing its
arguments doesn't need to be. Move the non-critical code out of the
mutex-protected section.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/staging/media/omap4iss/iss_video.c

@@ -243,12 +243,11 @@ __iss_video_get_format(struct iss_video *video, struct v4l2_format *format)
 	if (subdev == NULL)
 		return -EINVAL;
 
-	mutex_lock(&video->mutex);
-
 	fmt.pad = pad;
 	fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
-	ret = v4l2_subdev_call(subdev, pad, get_fmt, NULL, &fmt);
 
+	mutex_lock(&video->mutex);
+	ret = v4l2_subdev_call(subdev, pad, get_fmt, NULL, &fmt);
 	mutex_unlock(&video->mutex);
 
 	if (ret)