The driver doesn't support clause 45 register access yet, but doesn't
check if the access is a c45 one either. This leads to spurious register
reads and writes. Add the check.
Fixes: 542671fe4d86 ("net: phy: mscc-miim: Add MDIO driver")
Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
        u32 val;
        int ret;
 
+       if (regnum & MII_ADDR_C45)
+               return -EOPNOTSUPP;
+
        ret = mscc_miim_wait_pending(bus);
        if (ret)
                goto out;
        struct mscc_miim_dev *miim = bus->priv;
        int ret;
 
+       if (regnum & MII_ADDR_C45)
+               return -EOPNOTSUPP;
+
        ret = mscc_miim_wait_pending(bus);
        if (ret < 0)
                goto out;