phy: rockchip-inno-usb2: turn off differential receiver in suspend mode

Turn off differential receiver in suspend mode to save power

Change-Id: Idd9b4c2d7d9d78915c94946ced99737683a2ce91
Signed-off-by: Meng Dongyang <daniel.meng@rock-chips.com>

Author: Meng Dongyang

drivers/phy/rockchip/phy-rockchip-inno-usb2.c

@@ -1777,6 +1777,18 @@ static int rockchip_usb2phy_probe(struct platform_device *pdev)
 	return ret;
 }
 
+static int rk312x_usb2phy_tuning(struct rockchip_usb2phy *rphy)
+{
+	int ret;
+
+	/* Turn off differential receiver in suspend mode */
+	ret = regmap_write(rphy->grf, 0x298, 0x00040000);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
 static int rk3328_usb2phy_tuning(struct rockchip_usb2phy *rphy)
 {
 	int ret;
@@ -1970,6 +1982,7 @@ static const struct rockchip_usb2phy_cfg rk312x_phy_cfgs[] = {
 	{
 		.reg = 0x17c,
 		.num_ports	= 2,
+		.phy_tuning	= rk312x_usb2phy_tuning,
 		.clkout_ctl	= { 0x0190, 15, 15, 1, 0 },
 		.port_cfgs	= {
 			[USB2PHY_PORT_OTG] = {