net: phy: probe for C45 PHYs that return PHY ID of zero in C22 space

PHY devices such as the Marvell Alaska 88E2110 does not return a valid
PHY ID when probed using Clause-22. The current implementation treats
PHY ID of zero as a non-error and valid PHY ID, and causing the PHY
device failed to bind to the Marvell driver.

For such devices, we do an additional probe in the Clause-45 space,
if a valid PHY ID is returned, we then proceed to attach the PHY
device to the matching PHY ID driver.

Signed-off-by: Wong Vee Khee <vee.khee.wong@linux.intel.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 1539ea021ac086c6e76c94b253eab99a495f9d87..495d86b4af7cf42858d5d77f7ba7b4fabe27e1b5 100644 (file)
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -870,6 +870,18 @@ struct phy_device *get_phy_device(struct mii_bus *bus, int addr, bool is_c45)
        if (r)
                return ERR_PTR(r);
 
+       /* PHY device such as the Marvell Alaska 88E2110 will return a PHY ID
+        * of 0 when probed using get_phy_c22_id() with no error. Proceed to
+        * probe with C45 to see if we're able to get a valid PHY ID in the C45
+        * space, if successful, create the C45 PHY device.
+        */
+       if (!is_c45 && phy_id == 0 && bus->probe_capabilities >= MDIOBUS_C45) {
+               r = get_phy_c45_ids(bus, addr, &c45_ids);
+               if (!r)
+                       return phy_device_create(bus, addr, phy_id,
+                                                true, &c45_ids);
+       }
+
        return phy_device_create(bus, addr, phy_id, is_c45, &c45_ids);
 }
 EXPORT_SYMBOL(get_phy_device);