usb: typec: hd3ss3220: Use OF graph API to get the connector fwnode

Some platforms have only super speed data bus connected to this device
and high speed data bus directly connected to the SoC. In such platforms
modelling connector as a child of this device is making it non compliant
with usb connector bindings. By modelling connector node as standalone
device node along with this device and the SoC data bus will make it
compliant with usb connector bindings.
Update the driver to handle this model by using OF graph API to get the
connector fwnode and usb role switch class API to get role switch handle.

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20200920134905.4370-5-biju.das.jz@bp.renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/typec/hd3ss3220.c

@@ -155,7 +155,7 @@ static int hd3ss3220_probe(struct i2c_client *client,
 {
 	struct typec_capability typec_cap = { };
 	struct hd3ss3220 *hd3ss3220;
-	struct fwnode_handle *connector;
+	struct fwnode_handle *connector, *ep;
 	int ret;
 	unsigned int data;
 
@@ -173,11 +173,21 @@ static int hd3ss3220_probe(struct i2c_client *client,
 
 	hd3ss3220_set_source_pref(hd3ss3220,
 				  HD3SS3220_REG_GEN_CTRL_SRC_PREF_DRP_DEFAULT);
+	/* For backward compatibility check the connector child node first */
 	connector = device_get_named_child_node(hd3ss3220->dev, "connector");
-	if (!connector)
-		return -ENODEV;
+	if (connector) {
+		hd3ss3220->role_sw = fwnode_usb_role_switch_get(connector);
+	} else {
+		ep = fwnode_graph_get_next_endpoint(dev_fwnode(hd3ss3220->dev), NULL);
+		if (!ep)
+			return -ENODEV;
+		connector = fwnode_graph_get_remote_port_parent(ep);
+		fwnode_handle_put(ep);
+		if (!connector)
+			return -ENODEV;
+		hd3ss3220->role_sw = usb_role_switch_get(hd3ss3220->dev);
+	}
 
-	hd3ss3220->role_sw = fwnode_usb_role_switch_get(connector);
 	if (IS_ERR(hd3ss3220->role_sw)) {
 		ret = PTR_ERR(hd3ss3220->role_sw);
 		goto err_put_fwnode;