net/phy/cortina.c: Update get_phy_id implementation

Update get_phy_id() implementation in cortina.c to check
for Cortina_phy by comparing device phy_id with cortina phy_id
instead of relying on presence of CORTINA macros.

This will allow get_phy_id to work with non-cortina phy devices
which might have same phy address as Cortina device but on
different  bus.

Signed-off-by: Priyanka Jain <priyanka.jain@nxp.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>

drivers/net/phy/cortina.c

@@ -295,45 +295,33 @@ int phy_cortina_init(void)
 int get_phy_id(struct mii_dev *bus, int addr, int devad, u32 *phy_id)
 {
 	int phy_reg;
-	bool is_cortina_phy = false;
-
-	switch (addr) {
-#ifdef CORTINA_PHY_ADDR1
-	case CORTINA_PHY_ADDR1:
-#endif
-#ifdef CORTINA_PHY_ADDR2
-	case CORTINA_PHY_ADDR2:
-#endif
-#ifdef CORTINA_PHY_ADDR3
-	case CORTINA_PHY_ADDR3:
-#endif
-#ifdef CORTINA_PHY_ADDR4
-	case CORTINA_PHY_ADDR4:
-#endif
-		is_cortina_phy = true;
-		break;
-	default:
-		break;
-	}
 
 	/* Cortina PHY has non-standard offset of PHY ID registers */
-	if (is_cortina_phy)
-		phy_reg = bus->read(bus, addr, 0, VILLA_GLOBAL_CHIP_ID_LSB);
-	else
-		phy_reg = bus->read(bus, addr, devad, MII_PHYSID1);
+	phy_reg = bus->read(bus, addr, 0, VILLA_GLOBAL_CHIP_ID_LSB);
+	if (phy_reg < 0)
+		return -EIO;
+	*phy_id = (phy_reg & 0xffff) << 16;
 
+	phy_reg = bus->read(bus, addr, 0, VILLA_GLOBAL_CHIP_ID_MSB);
 	if (phy_reg < 0)
 		return -EIO;
+	*phy_id |= (phy_reg & 0xffff);
 
-	*phy_id = (phy_reg & 0xffff) << 16;
-	if (is_cortina_phy)
-		phy_reg = bus->read(bus, addr, 0, VILLA_GLOBAL_CHIP_ID_MSB);
-	else
-		phy_reg = bus->read(bus, addr, devad, MII_PHYSID2);
+	if (*phy_id == PHY_UID_CS4340)
+		return 0;
 
+	/*
+	 * If Cortina PHY not detected,
+	 * try generic way to find PHY ID registers
+	 */
+	phy_reg = bus->read(bus, addr, devad, MII_PHYSID1);
 	if (phy_reg < 0)
 		return -EIO;
+	*phy_id = (phy_reg & 0xffff) << 16;
 
+	phy_reg = bus->read(bus, addr, devad, MII_PHYSID2);
+	if (phy_reg < 0)
+		return -EIO;
 	*phy_id |= (phy_reg & 0xffff);
 
 	return 0;