From 9fe73155dccde51fca4072700c11145f683dc832 Mon Sep 17 00:00:00 2001
From: Douglas Anderson <dianders@chromium.org>
Date: Fri, 22 Sep 2017 09:44:06 -0700
Subject: [PATCH 46/86] phy: rockchip-typec: Do the calibration more correctly

Git-commit: e023b1fb5286e23c224f2ae312831a4fce258c02
Patch-mainline: Queued
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
References: fate#323912

Calculate the calibration code as per the docs.  The docs talk about
reading and averaging the pullup and pulldown calibration codes.  They
also talk about adding in some adjustment codes.  Let's do what the
docs say.

In practice this doesn't seem to matter a whole lot.  On a device I
tested the pullup and pulldown codes were nearly the same (0x23 and
0x24) and the adjustment codes were 0.

Reviewed-by: Chris Zhong <zyw@rock-chips.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com>
---
 drivers/phy/rockchip/phy-rockchip-typec.c | 27 ++++++++++++++++++---------
 1 file changed, 18 insertions(+), 9 deletions(-)

diff --git a/drivers/phy/rockchip/phy-rockchip-typec.c b/drivers/phy/rockchip/phy-rockchip-typec.c
index e5454eccb57d..ee85fa0ca4b0 100644
--- a/drivers/phy/rockchip/phy-rockchip-typec.c
+++ b/drivers/phy/rockchip/phy-rockchip-typec.c
@@ -560,24 +560,33 @@ static void tcphy_dp_aux_calibration(struct rockchip_typec_phy *tcphy)
 	u16 val;
 	u16 tx_ana_ctrl_reg_1;
 	u16 tx_ana_ctrl_reg_2;
-	s32 pu_calib_code;
-
-	/* disable txda_cal_latch_en for rewrite the calibration values */
-	tx_ana_ctrl_reg_1 = readl(tcphy->base + TX_ANA_CTRL_REG_1);
-	tx_ana_ctrl_reg_1 &= ~TXDA_CAL_LATCH_EN;
-	writel(tx_ana_ctrl_reg_1, tcphy->base + TX_ANA_CTRL_REG_1);
+	s32 pu_calib_code, pd_calib_code;
+	s32 pu_adj, pd_adj;
+	u16 calib;
 
 	/*
-	 * read a resistor calibration code from CMN_TXPUCAL_CTRL[5:0] and
-	 * write it to TX_DIG_CTRL_REG_2[5:0].
+	 * Calculate calibration code as per docs: use an average of the
+	 * pull down and pull up.  Then add in adjustments.
 	 */
 	val = readl(tcphy->base + CMN_TXPUCAL_CTRL);
 	pu_calib_code = CMN_CALIB_CODE_POS(val);
+	val = readl(tcphy->base + CMN_TXPDCAL_CTRL);
+	pd_calib_code = CMN_CALIB_CODE_POS(val);
+	val = readl(tcphy->base + CMN_TXPU_ADJ_CTRL);
+	pu_adj = CMN_CALIB_CODE(val);
+	val = readl(tcphy->base + CMN_TXPD_ADJ_CTRL);
+	pd_adj = CMN_CALIB_CODE(val);
+	calib = (pu_calib_code + pd_calib_code) / 2 + pu_adj + pd_adj;
+
+	/* disable txda_cal_latch_en for rewrite the calibration values */
+	tx_ana_ctrl_reg_1 = readl(tcphy->base + TX_ANA_CTRL_REG_1);
+	tx_ana_ctrl_reg_1 &= ~TXDA_CAL_LATCH_EN;
+	writel(tx_ana_ctrl_reg_1, tcphy->base + TX_ANA_CTRL_REG_1);
 
 	/* write the calibration, then delay 10 ms as sample in docs */
 	val = readl(tcphy->base + TX_DIG_CTRL_REG_2);
 	val &= ~(TX_RESCAL_CODE_MASK << TX_RESCAL_CODE_OFFSET);
-	val |= pu_calib_code << TX_RESCAL_CODE_OFFSET;
+	val |= calib << TX_RESCAL_CODE_OFFSET;
 	writel(val, tcphy->base + TX_DIG_CTRL_REG_2);
 	usleep_range(10000, 10050);
 
-- 
2.11.0