ravb: Add fixed-link support

This patch adds support of the fixed PHY.
This patch is based on commit 87009814cdbb ("ucc_geth: use the new fixed
PHY helpers").

Signed-off-by: Kazuya Mizuguchi <kazuya.mizuguchi.ks@renesas.com>
Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/renesas/ravb_main.c

@@ -882,6 +882,7 @@ static int ravb_phy_init(struct net_device *ndev)
 	struct ravb_private *priv = netdev_priv(ndev);
 	struct phy_device *phydev;
 	struct device_node *pn;
+	int err;
 
 	priv->link = 0;
 	priv->speed = 0;
@@ -889,6 +890,17 @@ static int ravb_phy_init(struct net_device *ndev)
 
 	/* Try connecting to PHY */
 	pn = of_parse_phandle(np, "phy-handle", 0);
+	if (!pn) {
+		/* In the case of a fixed PHY, the DT node associated
+		 * to the PHY is the Ethernet MAC DT node.
+		 */
+		if (of_phy_is_fixed_link(np)) {
+			err = of_phy_register_fixed_link(np);
+			if (err)
+				return err;
+		}
+		pn = of_node_get(np);
+	}
 	phydev = of_phy_connect(ndev, pn, ravb_adjust_link, 0,
 				priv->phy_interface);
 	if (!phydev) {