phy/marvell: Make non-aneg speed/duplex forcing work for 88E1111 PHYs

According to specs, when auto-negotiation is disabled, Marvell PHYs need
a software reset after changing speed/duplex forcing bits. Otherwise,
the modified bits have no effect.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/phy/marvell.c

@@ -155,8 +155,27 @@ static int marvell_config_aneg(struct phy_device *phydev)
 		return err;
 
 	err = genphy_config_aneg(phydev);
+	if (err < 0)
+		return err;
+
+	if (phydev->autoneg != AUTONEG_ENABLE) {
+		int bmcr;
 
+		/*
+		 * A write to speed/duplex bits (that is performed by
+		 * genphy_config_aneg() call above) must be followed by
+		 * a software reset. Otherwise, the write has no effect.
+		 */
+		bmcr = phy_read(phydev, MII_BMCR);
+		if (bmcr < 0)
+			return bmcr;
+
+		err = phy_write(phydev, MII_BMCR, bmcr | BMCR_RESET);
+		if (err < 0)
 			return err;
+	}
+
+	return 0;
 }
 
 static int m88e1121_config_aneg(struct phy_device *phydev)