--- zzzz-none-000/linux-4.4.271/include/linux/of_mdio.h	2021-06-03 06:22:09.000000000 +0000
+++ dakota-7530ac-750/linux-4.4.271/include/linux/of_mdio.h	2023-01-11 09:25:43.000000000 +0000
@@ -25,6 +25,8 @@
 
 extern struct mii_bus *of_mdio_find_bus(struct device_node *mdio_np);
 extern int of_mdio_parse_addr(struct device *dev, const struct device_node *np);
+extern int of_mdiobus_register_phy(struct mii_bus *mdio,
+		struct device_node *child, u32 addr);
 
 #else /* CONFIG_OF */
 static inline int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
@@ -67,6 +69,12 @@
 {
 	return -ENOSYS;
 }
+
+static int of_mdiobus_register_phy(struct mii_bus *mdio,
+		struct device_node *child, u32 addr)
+{
+	return -ENOSYS;
+}
 #endif /* CONFIG_OF */
 
 #if defined(CONFIG_OF) && defined(CONFIG_FIXED_PHY)