diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c
index bde195864c1788ef86b213c229c425ab9f742b8a..c992a9fd8b012e22aa9ac221c1bd165af5aa135e 100644
--- a/drivers/net/phy/mdio_bus.c
+++ b/drivers/net/phy/mdio_bus.c
@@ -526,8 +526,15 @@ int __mdiobus_register(struct mii_bus *bus, struct module *owner)
 	int i, err;
 	struct gpio_desc *gpiod;
 
-	if (NULL == bus || NULL == bus->name ||
-	    NULL == bus->read || NULL == bus->write)
+	if (!bus || !bus->name)
+		return -EINVAL;
+
+	/* An access method always needs both read and write operations */
+	if (!!bus->read != !!bus->write || !!bus->read_c45 != !!bus->write_c45)
+		return -EINVAL;
+
+	/* At least one method is mandatory */
+	if (!bus->read && !bus->read_c45)
 		return -EINVAL;
 
 	if (bus->parent && bus->parent->of_node)