From e4fe585d6bae13c5462e15c4e64525bcfa36efba Mon Sep 17 00:00:00 2001
From: William Wu <william.wu@rock-chips.com>
Date: Mon, 26 Mar 2018 19:32:37 +0800
Subject: [PATCH] phy: rockchip-inno-usb2: open pre-emphasize for rk3308/rk3328

Open pre-emphasize in non-chirp state for rk3308 and
rk3328 usb otg and host ports to increase HS slew rate.

Change-Id: I16435d67b9994cef0fd5e6edbae00c41cc02c48b
Signed-off-by: William Wu <william.wu@rock-chips.com>
Signed-off-by: Frank Wang <frank.wang@rock-chips.com>
---
 drivers/phy/rockchip/phy-rockchip-inno-usb2.c | 35 ++++++++++++++++---
 1 file changed, 30 insertions(+), 5 deletions(-)

diff --git a/drivers/phy/rockchip/phy-rockchip-inno-usb2.c b/drivers/phy/rockchip/phy-rockchip-inno-usb2.c
index a2eef9b0bebe..111ce6f534cb 100644
--- a/drivers/phy/rockchip/phy-rockchip-inno-usb2.c
+++ b/drivers/phy/rockchip/phy-rockchip-inno-usb2.c
@@ -1873,6 +1873,28 @@ static int rk312x_usb2phy_tuning(struct rockchip_usb2phy *rphy)
 	return 0;
 }
 
+static int rk3308_usb2phy_tuning(struct rockchip_usb2phy *rphy)
+{
+	int ret;
+
+	/* Open pre-emphasize in non-chirp state for otg port */
+	ret = regmap_write(rphy->grf, 0x0, 0x00070004);
+	if (ret)
+		return ret;
+
+	/* Open pre-emphasize in non-chirp state for host port */
+	ret = regmap_write(rphy->grf, 0x30, 0x00070004);
+	if (ret)
+		return ret;
+
+	/* Turn off differential receiver in suspend mode */
+	ret = regmap_write(rphy->grf, 0x18, 0x00040000);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
 static int rk3328_usb2phy_tuning(struct rockchip_usb2phy *rphy)
 {
 	int ret;
@@ -1882,11 +1904,13 @@ static int rk3328_usb2phy_tuning(struct rockchip_usb2phy *rphy)
 	if (ret)
 		return ret;
 
-	/*
-	 * Open HS pre-emphasize function to increase
-	 * HS slew rate for host port
-	 */
-	ret = regmap_write(rphy->grf, 0x30, 0xffff851d);
+	/* Open pre-emphasize in non-chirp state for otg port */
+	ret = regmap_write(rphy->grf, 0x0, 0x00070004);
+	if (ret)
+		return ret;
+
+	/* Open pre-emphasize in non-chirp state for host port */
+	ret = regmap_write(rphy->grf, 0x30, 0x00070004);
 	if (ret)
 		return ret;
 
@@ -2211,6 +2235,7 @@ static const struct rockchip_usb2phy_cfg rk3308_phy_cfgs[] = {
 	{
 		.reg = 0x100,
 		.num_ports	= 2,
+		.phy_tuning	= rk3308_usb2phy_tuning,
 		.clkout_ctl	= { 0x0108, 4, 4, 1, 0 },
 		.port_cfgs	= {
 			[USB2PHY_PORT_OTG] = {