diff --git a/drivers/net/ethernet/oa_tc6.c b/drivers/net/ethernet/oa_tc6.c
index 955148d3cefc..417c15d1ff42 100644
--- a/drivers/net/ethernet/oa_tc6.c
+++ b/drivers/net/ethernet/oa_tc6.c
@@ -499,13 +499,14 @@ int oa_tc6_mdiobus_read_c45(struct mii_bus *bus, int addr, int devnum,
 {
 	struct oa_tc6 *tc6 = bus->priv;
 	u32 regval;
+	int mms;
 	int ret;
 
-	ret = oa_tc6_get_phy_c45_mms(devnum);
-	if (ret < 0)
-		return ret;
+	mms = oa_tc6_get_phy_c45_mms(devnum);
+	if (mms < 0)
+		return mms;
 
-	ret = oa_tc6_read_register(tc6, (ret << 16) | regnum, &regval);
+	ret = oa_tc6_read_register_mms(tc6, mms, regnum, &regval);
 	if (ret)
 		return ret;
 
@@ -517,13 +518,13 @@ int oa_tc6_mdiobus_write_c45(struct mii_bus *bus, int addr, int devnum,
 			     int regnum, u16 val)
 {
 	struct oa_tc6 *tc6 = bus->priv;
-	int ret;
+	int mms;
 
-	ret = oa_tc6_get_phy_c45_mms(devnum);
-	if (ret < 0)
-		return ret;
+	mms = oa_tc6_get_phy_c45_mms(devnum);
+	if (mms < 0)
+		return mms;
 
-	return oa_tc6_write_register(tc6, (ret << 16) | regnum, val);
+	return oa_tc6_write_register_mms(tc6, mms, regnum, val);
 }
 EXPORT_SYMBOL_GPL(oa_tc6_mdiobus_write_c45);