of: property: Skip adding device links to suppliers that aren't devices

Some devices need to be initialized really early and can't wait for
driver core or drivers to be functional.  These devices are typically
initialized without creating a struct device for their device nodes.

If a supplier ends up being one of these devices, skip trying to add
device links to them.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20191028220027.251605-6-saravanak@google.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/of/property.c

@@ -1024,6 +1024,7 @@ static int of_link_to_phandle(struct device *dev, struct device_node *sup_np,
 	struct device *sup_dev;
 	int ret = 0;
 	struct device_node *tmp_np = sup_np;
+	int is_populated;
 
 	of_node_get(sup_np);
 	/*
@@ -1048,9 +1049,10 @@ static int of_link_to_phandle(struct device *dev, struct device_node *sup_np,
 		return -EINVAL;
 	}
 	sup_dev = get_dev_from_fwnode(&sup_np->fwnode);
+	is_populated = of_node_check_flag(sup_np, OF_POPULATED);
 	of_node_put(sup_np);
 	if (!sup_dev)
-		return -EAGAIN;
+		return is_populated ? 0 : -EAGAIN;
 	if (!device_link_add(dev, sup_dev, dl_flags))
 		ret = -EAGAIN;
 	put_device(sup_dev);