diff --git a/drivers/net/dsa/b53/b53_common.c b/drivers/net/dsa/b53/b53_common.c
index 59cdfc51ce06..922e5934de73 100644
--- a/drivers/net/dsa/b53/b53_common.c
+++ b/drivers/net/dsa/b53/b53_common.c
@@ -2221,6 +2221,9 @@ static int b53_change_mtu(struct dsa_switch *ds, int port, int mtu)
 	if (is5325(dev) || is5365(dev))
 		return -EOPNOTSUPP;
 
+	if (!dsa_is_cpu_port(ds, port))
+		return 0;
+
 	enable_jumbo = (mtu >= JMS_MIN_SIZE);
 	allow_10_100 = (dev->chip_id == BCM583XX_DEVICE_ID);