net: macb: fix for fixed-link mode

This patch fix the issue with fixed link. With fixed-link
device opening fails due to macb_phylink_connect not
handling fixed-link mode, in which case no MAC-PHY connection
is needed and phylink_connect return success (0), however
in current driver attempt is made to search and connect to
PHY even for fixed-link.

Fixes: 7897b071 ("net: macb: convert to phylink")
Signed-off-by: Milind Parab <mparab@cadence.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/cadence/macb_main.c

@@ -611,21 +611,24 @@ static const struct phylink_mac_ops macb_phylink_ops = {
 	.mac_link_up = macb_mac_link_up,
 };
 
+static bool macb_phy_handle_exists(struct device_node *dn)
+{
+	dn = of_parse_phandle(dn, "phy-handle", 0);
+	of_node_put(dn);
+	return dn != NULL;
+}
+
 static int macb_phylink_connect(struct macb *bp)
 {
+	struct device_node *dn = bp->pdev->dev.of_node;
 	struct net_device *dev = bp->dev;
 	struct phy_device *phydev;
 	int ret;
 
-	if (bp->pdev->dev.of_node &&
-	    of_parse_phandle(bp->pdev->dev.of_node, "phy-handle", 0)) {
-		ret = phylink_of_phy_connect(bp->phylink, bp->pdev->dev.of_node,
-					     0);
-		if (ret) {
-			netdev_err(dev, "Could not attach PHY (%d)\n", ret);
-			return ret;
-		}
-	} else {
+	if (dn)
+		ret = phylink_of_phy_connect(bp->phylink, dn, 0);
+
+	if (!dn || (ret && !macb_phy_handle_exists(dn))) {
 		phydev = phy_find_first(bp->mii_bus);
 		if (!phydev) {
 			netdev_err(dev, "no PHY found\n");
@@ -634,10 +637,11 @@ static int macb_phylink_connect(struct macb *bp)
 
 		/* attach the mac to the phy */
 		ret = phylink_connect_phy(bp->phylink, phydev);
-		if (ret) {
-			netdev_err(dev, "Could not attach to PHY (%d)\n", ret);
-			return ret;
-		}
+	}
+
+	if (ret) {
+		netdev_err(dev, "Could not attach PHY (%d)\n", ret);
+		return ret;
 	}
 
 	phylink_start(bp->phylink);