phy: micrel: Fix finding PHY properties in MAC node for KSZ9031.

BugLink: https://bugs.launchpad.net/bugs/1878232

commit b4c19f71 upstream.

Commit 651df218 ("phy: micrel: Fix finding PHY properties in MAC
 node.") only fixes finding PHY properties in MAC node for KSZ9021. This
commit applies the same fix for KSZ9031.

Fixes: 8b63ec18 ("phylib: Make PHYs children of their MDIO bus, not the bus' parent.")
Acked-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Henri Roosen <henri.roosen@ginzinger.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ian May <ian.may@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

drivers/net/phy/micrel.c

@@ -482,9 +482,17 @@ static int ksz9031_config_init(struct phy_device *phydev)
 		"txd2-skew-ps", "txd3-skew-ps"
 	};
 	static const char *control_skews[2] = {"txen-skew-ps", "rxdv-skew-ps"};
+	const struct device *dev_walker;
 
-	if (!of_node && dev->parent->of_node)
-		of_node = dev->parent->of_node;
+	/* The Micrel driver has a deprecated option to place phy OF
+	 * properties in the MAC node. Walk up the tree of devices to
+	 * find a device with an OF node.
+	 */
+	dev_walker = &phydev->dev;
+	do {
+		of_node = dev_walker->of_node;
+		dev_walker = dev_walker->parent;
+	} while (!of_node && dev_walker);
 
 	if (of_node) {
 		ksz9031_of_load_skew_values(phydev, of_node,