diff --git a/drivers/net/phy/mdio_devres.c b/drivers/net/phy/mdio_devres.c
index f0b4b6cfe5e3..3ee887733d4a 100644
--- a/drivers/net/phy/mdio_devres.c
+++ b/drivers/net/phy/mdio_devres.c
@@ -2,6 +2,13 @@
 
 #include <linux/phy.h>
 
+/**
+ * __devm_mdiobus_register - Resource-managed variant of mdiobus_register()
+ * @bus:	MII bus structure to register
+ * @owner:	Owning module
+ *
+ * Returns 0 on success, negative error number on failure.
+ */
 int __devm_mdiobus_register(struct mii_bus *bus, struct module *owner)
 {
 	int ret;