net: phy: allow phy_init_eee() to work with internal PHYs

Internal PHYs do not have any specific phy_interface_t defined because
they are within an Ethernet MAC or a larger IC, they will fail the early
check in phy_init_eee(). Allow these PHYs to proceed with EEE
initialization and report error/success by checking the standard C45
EEE-related registers.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
index e7a5893..932190e 100644
--- a/drivers/net/phy/phy.c
+++ b/drivers/net/phy/phy.c
@@ -1019,12 +1019,14 @@
 {
 	/* According to 802.3az,the EEE is supported only in full duplex-mode.
 	 * Also EEE feature is active when core is operating with MII, GMII
-	 * or RGMII.
+	 * or RGMII. Internal PHYs are also allowed to proceed and should
+	 * return an error if they do not support EEE.
 	 */
 	if ((phydev->duplex == DUPLEX_FULL) &&
 	    ((phydev->interface == PHY_INTERFACE_MODE_MII) ||
 	    (phydev->interface == PHY_INTERFACE_MODE_GMII) ||
-	    (phydev->interface == PHY_INTERFACE_MODE_RGMII))) {
+	    (phydev->interface == PHY_INTERFACE_MODE_RGMII) ||
+	     phy_is_internal(phydev))) {
 		int eee_lp, eee_cap, eee_adv;
 		u32 lp, cap, adv;
 		int status;