usb: phy: mxs: add controller id

It is used to access un-regulator registers according to
different controllers.
Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/phy/phy-mxs-usb.c

@@ -106,6 +106,7 @@ struct mxs_phy {
 	struct clk *clk;
 	const struct mxs_phy_data *data;
 	struct regmap *regmap_anatop;
+	int port_id;
 };
 
 static int mxs_phy_hw_init(struct mxs_phy *mxs_phy)
@@ -250,6 +251,11 @@ static int mxs_phy_probe(struct platform_device *pdev)
 		}
 	}
 
+	ret = of_alias_get_id(np, "usbphy");
+	if (ret < 0)
+		dev_dbg(&pdev->dev, "failed to get alias id, errno %d\n", ret);
+	mxs_phy->port_id = ret;
+
 	mxs_phy->phy.io_priv		= base;
 	mxs_phy->phy.dev		= &pdev->dev;
 	mxs_phy->phy.label		= DRIVER_NAME;