phy: rockchip-usb: should be a child device of the GRF

The usb-phy is fully enclosed in the general register files (GRF).
Therefore as seen from the device-tree it shouldn't be a separate
platform-device but instead a sub-device of the GRF - using the
simply-mfd mechanism.

As the usb-phy is part of the kernel for some releases now, we keep
the old (and now deprecated) binding for compatibility purposes.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
diff --git a/drivers/phy/phy-rockchip-usb.c b/drivers/phy/phy-rockchip-usb.c
index d60b149..e66b5bf 100644
--- a/drivers/phy/phy-rockchip-usb.c
+++ b/drivers/phy/phy-rockchip-usb.c
@@ -397,8 +397,13 @@
 	phy_base->pdata = match->data;
 
 	phy_base->dev = dev;
-	phy_base->reg_base = syscon_regmap_lookup_by_phandle(dev->of_node,
-							     "rockchip,grf");
+	phy_base->reg_base = ERR_PTR(-ENODEV);
+	if (dev->parent && dev->parent->of_node)
+		phy_base->reg_base = syscon_node_to_regmap(
+						dev->parent->of_node);
+	if (IS_ERR(phy_base->reg_base))
+		phy_base->reg_base = syscon_regmap_lookup_by_phandle(
+						dev->of_node, "rockchip,grf");
 	if (IS_ERR(phy_base->reg_base)) {
 		dev_err(&pdev->dev, "Missing rockchip,grf property\n");
 		return PTR_ERR(phy_base->reg_base);
@@ -463,7 +468,11 @@
 		return -ENOTSUPP;
 	}
 
-	grf = syscon_regmap_lookup_by_phandle(np, "rockchip,grf");
+	grf = ERR_PTR(-ENODEV);
+	if (np->parent)
+		grf = syscon_node_to_regmap(np->parent);
+	if (IS_ERR(grf))
+		grf = syscon_regmap_lookup_by_phandle(np, "rockchip,grf");
 	if (IS_ERR(grf)) {
 		pr_err("%s: Missing rockchip,grf property, %lu\n",
 		       __func__, PTR_ERR(grf));