phy: core: Fix of_phy_provider_lookup to return PHY provider for sub node

Fixed of_phy_provider_lookup to return 'phy_provider' if _of_phy_get
passes the node pointer of the sub-node of phy provider node. This is
needed when phy provider implements multiple PHYs and each PHY is
modelled as the sub-node of PHY provider device node.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c
index 75c9739..527e744 100644
--- a/drivers/phy/phy-core.c
+++ b/drivers/phy/phy-core.c
@@ -87,10 +87,15 @@
 static struct phy_provider *of_phy_provider_lookup(struct device_node *node)
 {
 	struct phy_provider *phy_provider;
+	struct device_node *child;
 
 	list_for_each_entry(phy_provider, &phy_provider_list, list) {
 		if (phy_provider->dev->of_node == node)
 			return phy_provider;
+
+		for_each_child_of_node(phy_provider->dev->of_node, child)
+			if (child == node)
+				return phy_provider;
 	}
 
 	return ERR_PTR(-EPROBE_DEFER);