diff --git a/drivers/media/platform/omap3isp/ispvideo.c b/drivers/media/platform/omap3isp/ispvideo.c
index 04d45e70d3be..2876f34b84c0 100644
--- a/drivers/media/platform/omap3isp/ispvideo.c
+++ b/drivers/media/platform/omap3isp/ispvideo.c
@@ -631,17 +631,16 @@ isp_video_set_format(struct file *file, void *fh, struct v4l2_format *format)
 	if (format->type != video->type)
 		return -EINVAL;
 
-	mutex_lock(&video->mutex);
-
 	/* Fill the bytesperline and sizeimage fields by converting to media bus
 	 * format and back to pixel format.
 	 */
 	isp_video_pix_to_mbus(&format->fmt.pix, &fmt);
 	isp_video_mbus_to_pix(video, &fmt, &format->fmt.pix);
 
+	mutex_lock(&video->mutex);
 	vfh->format = *format;
-
 	mutex_unlock(&video->mutex);
+
 	return 0;
 }