[media] adv7604: return immediately if the new timings are equal to what is configured

Signed-off-by: Mats Randgaard <matrandg@cisco.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
diff --git a/drivers/media/i2c/adv7604.c b/drivers/media/i2c/adv7604.c
index 912c59e..0bc9e1a 100644
--- a/drivers/media/i2c/adv7604.c
+++ b/drivers/media/i2c/adv7604.c
@@ -1423,6 +1423,11 @@
 	if (!timings)
 		return -EINVAL;
 
+	if (v4l2_match_dv_timings(&state->timings, timings, 0)) {
+		v4l2_dbg(1, debug, sd, "%s: no change\n", __func__);
+		return 0;
+	}
+
 	bt = &timings->bt;
 
 	if ((is_analog_input(sd) && bt->pixelclock > 170000000) ||