diff --git a/target/linux/ramips/files/drivers/net/ethernet/ralink/gsw_mt7620a.c b/target/linux/ramips/files/drivers/net/ethernet/ralink/gsw_mt7620a.c
index e31dd29b42..c0ec939263 100644
--- a/target/linux/ramips/files/drivers/net/ethernet/ralink/gsw_mt7620a.c
+++ b/target/linux/ramips/files/drivers/net/ethernet/ralink/gsw_mt7620a.c
@@ -299,6 +299,9 @@ static void gsw_auto_poll(struct mt7620_gsw *gsw)
 		msb = phy;
 	}
 
+	if (lsb)
+		lsb--;
+
 	gsw_w32(gsw, PHY_AN_EN | PHY_PRE_EN | PMY_MDC_CONF(5) | (msb << 8) | lsb, ESW_PHY_POLLING);
 }