net: phy: Marvell: Add mv88e6390 internal PHY

The mv88e6390 Ethernet switch has internal PHYs. These PHYs don't have
an model ID in the ID2 register. So the MDIO driver in the switch
intercepts reads to this register, and returns the switch family ID.
Extend the Marvell PHY driver by including this ID, and treat the PHY
as a 88E1540.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/marvell_phy.h b/include/linux/marvell_phy.h
index a57f0df..3d616d7 100644
--- a/include/linux/marvell_phy.h
+++ b/include/linux/marvell_phy.h
@@ -19,6 +19,12 @@
 #define MARVELL_PHY_ID_88E1540		0x01410eb0
 #define MARVELL_PHY_ID_88E3016		0x01410e60
 
+/* The MV88e6390 Ethernet switch contains embedded PHYs. These PHYs do
+ * not have a model ID. So the switch driver traps reads to the ID2
+ * register and returns the switch family ID
+ */
+#define MARVELL_PHY_ID_88E6390		0x01410f90
+
 /* struct phy_device dev_flags definitions */
 #define MARVELL_PHY_M1145_FLAGS_RESISTANCE	0x00000001
 #define MARVELL_PHY_M1118_DNS323_LEDS		0x00000002