v4.19.13 snapshot.
diff --git a/include/linux/of_mdio.h b/include/linux/of_mdio.h
new file mode 100644
index 0000000..f5db93b
--- /dev/null
+++ b/include/linux/of_mdio.h
@@ -0,0 +1,119 @@
+/*
+ * OF helpers for the MDIO (Ethernet PHY) API
+ *
+ * Copyright (c) 2009 Secret Lab Technologies, Ltd.
+ *
+ * This file is released under the GPLv2
+ */
+
+#ifndef __LINUX_OF_MDIO_H
+#define __LINUX_OF_MDIO_H
+
+#include <linux/phy.h>
+#include <linux/of.h>
+
+#if IS_ENABLED(CONFIG_OF_MDIO)
+extern int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np);
+extern struct phy_device *of_phy_find_device(struct device_node *phy_np);
+extern struct phy_device *of_phy_connect(struct net_device *dev,
+ struct device_node *phy_np,
+ void (*hndlr)(struct net_device *),
+ u32 flags, phy_interface_t iface);
+extern struct phy_device *
+of_phy_get_and_connect(struct net_device *dev, struct device_node *np,
+ void (*hndlr)(struct net_device *));
+struct phy_device *of_phy_attach(struct net_device *dev,
+ struct device_node *phy_np, u32 flags,
+ phy_interface_t iface);
+
+extern struct mii_bus *of_mdio_find_bus(struct device_node *mdio_np);
+extern int of_phy_register_fixed_link(struct device_node *np);
+extern void of_phy_deregister_fixed_link(struct device_node *np);
+extern bool of_phy_is_fixed_link(struct device_node *np);
+
+
+static inline int of_mdio_parse_addr(struct device *dev,
+ const struct device_node *np)
+{
+ u32 addr;
+ int ret;
+
+ ret = of_property_read_u32(np, "reg", &addr);
+ if (ret < 0) {
+ dev_err(dev, "%s has invalid PHY address\n", np->full_name);
+ return ret;
+ }
+
+ /* A PHY must have a reg property in the range [0-31] */
+ if (addr >= PHY_MAX_ADDR) {
+ dev_err(dev, "%s PHY address %i is too large\n",
+ np->full_name, addr);
+ return -EINVAL;
+ }
+
+ return addr;
+}
+
+#else /* CONFIG_OF_MDIO */
+static inline int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
+{
+ /*
+ * Fall back to the non-DT function to register a bus.
+ * This way, we don't have to keep compat bits around in drivers.
+ */
+
+ return mdiobus_register(mdio);
+}
+
+static inline struct phy_device *of_phy_find_device(struct device_node *phy_np)
+{
+ return NULL;
+}
+
+static inline struct phy_device *of_phy_connect(struct net_device *dev,
+ struct device_node *phy_np,
+ void (*hndlr)(struct net_device *),
+ u32 flags, phy_interface_t iface)
+{
+ return NULL;
+}
+
+static inline struct phy_device *
+of_phy_get_and_connect(struct net_device *dev, struct device_node *np,
+ void (*hndlr)(struct net_device *))
+{
+ return NULL;
+}
+
+static inline struct phy_device *of_phy_attach(struct net_device *dev,
+ struct device_node *phy_np,
+ u32 flags, phy_interface_t iface)
+{
+ return NULL;
+}
+
+static inline struct mii_bus *of_mdio_find_bus(struct device_node *mdio_np)
+{
+ return NULL;
+}
+
+static inline int of_mdio_parse_addr(struct device *dev,
+ const struct device_node *np)
+{
+ return -ENOSYS;
+}
+static inline int of_phy_register_fixed_link(struct device_node *np)
+{
+ return -ENOSYS;
+}
+static inline void of_phy_deregister_fixed_link(struct device_node *np)
+{
+}
+static inline bool of_phy_is_fixed_link(struct device_node *np)
+{
+ return false;
+}
+#endif
+
+
+#endif /* __LINUX_OF_MDIO_H */