efi: Update implementation of add_links() to create fwnode links

The semantics of add_links() has changed from creating device link
between devices to creating fwnode links between fwnodes. So, update the
implementation of add_links() to match the new semantics.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20201121020232.908850-16-saravanak@google.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/firmware/efi/efi-init.c

@@ -320,7 +320,6 @@ static int efifb_add_links(struct fwnode_handle *fwnode,
 			   struct device *dev)
 {
 	struct device_node *sup_np;
-	struct device *sup_dev;
 
 	sup_np = find_pci_overlap_node();
 
@@ -331,27 +330,9 @@ static int efifb_add_links(struct fwnode_handle *fwnode,
 	if (!sup_np)
 		return 0;
 
-	sup_dev = get_dev_from_fwnode(&sup_np->fwnode);
+	fwnode_link_add(fwnode, of_fwnode_handle(sup_np));
 	of_node_put(sup_np);
 
-	/*
-	 * Return -ENODEV if the PCI graphics controller device hasn't been
-	 * registered yet.  This ensures that efifb isn't allowed to probe
-	 * and this function is retried again when new devices are
-	 * registered.
-	 */
-	if (!sup_dev)
-		return -ENODEV;
-
-	/*
-	 * If this fails, retrying this function at a later point won't
-	 * change anything. So, don't return an error after this.
-	 */
-	if (!device_link_add(dev, sup_dev, fw_devlink_get_flags()))
-		dev_warn(dev, "device_link_add() failed\n");
-
-	put_device(sup_dev);
-
 	return 0;
 }