net: phy: add interface mode PHY_INTERFACE_MODE_USXGMII

Add support for interface mode PHY_INTERFACE_MODE_USXGMII.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/phy.h

@@ -103,6 +103,7 @@ typedef enum {
 	PHY_INTERFACE_MODE_XAUI,
 	/* 10GBASE-KR, XFI, SFI - single lane 10G Serdes */
 	PHY_INTERFACE_MODE_10GKR,
+	PHY_INTERFACE_MODE_USXGMII,
 	PHY_INTERFACE_MODE_MAX,
 } phy_interface_t;
 
@@ -178,6 +179,8 @@ static inline const char *phy_modes(phy_interface_t interface)
 		return "xaui";
 	case PHY_INTERFACE_MODE_10GKR:
 		return "10gbase-kr";
+	case PHY_INTERFACE_MODE_USXGMII:
+		return "usxgmii";
 	default:
 		return "unknown";
 	}