commit e3c02009003eebf84f7c56c7f330521553c8d299
author Jingoo Han <jg1.han@samsung.com> Wed Sep 12 13:34:24 2012 +0900
committer Florian Tobias Schandinat <FlorianSchandinat@gmx.de> Sat Sep 22 21:39:53 2012 +0000
tree e46f7aadc47479976ce8bf8d9892d0bc5c2d5680
parent 42affc2de4d96634ba05b4e99313028e878a004c

video: exynos_dp: add bit-masking for LINK_TRAINING_CTL register

This patch adds bit-masking for LINK_TRAINING_CTL register, when
pre-emphasis level is set. The bit 3 and bit 2 of LINK_TRAINING_CTL
register are used for pre-emphasis level setting, so other bits
should be masked.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>

drivers/video/exynos/exynos_dp_reg.c

diff --git a/drivers/video/exynos/exynos_dp_reg.c b/drivers/video/exynos/exynos_dp_reg.c
index 20e441f..365be69 100644
--- a/drivers/video/exynos/exynos_dp_reg.c
+++ b/drivers/video/exynos/exynos_dp_reg.c
@@ -895,7 +895,9 @@
 {
 	u32 reg;
 
-	reg = level << PRE_EMPHASIS_SET_SHIFT;
+	reg = readl(dp->reg_base + EXYNOS_DP_LN0_LINK_TRAINING_CTL);
+	reg &= ~PRE_EMPHASIS_SET_MASK;
+	reg |= level << PRE_EMPHASIS_SET_SHIFT;
 	writel(reg, dp->reg_base + EXYNOS_DP_LN0_LINK_TRAINING_CTL);
 }
 
@@ -903,7 +905,9 @@
 {
 	u32 reg;
 
-	reg = level << PRE_EMPHASIS_SET_SHIFT;
+	reg = readl(dp->reg_base + EXYNOS_DP_LN1_LINK_TRAINING_CTL);
+	reg &= ~PRE_EMPHASIS_SET_MASK;
+	reg |= level << PRE_EMPHASIS_SET_SHIFT;
 	writel(reg, dp->reg_base + EXYNOS_DP_LN1_LINK_TRAINING_CTL);
 }
 
@@ -911,7 +915,9 @@
 {
 	u32 reg;
 
-	reg = level << PRE_EMPHASIS_SET_SHIFT;
+	reg = readl(dp->reg_base + EXYNOS_DP_LN2_LINK_TRAINING_CTL);
+	reg &= ~PRE_EMPHASIS_SET_MASK;
+	reg |= level << PRE_EMPHASIS_SET_SHIFT;
 	writel(reg, dp->reg_base + EXYNOS_DP_LN2_LINK_TRAINING_CTL);
 }
 
@@ -919,7 +925,9 @@
 {
 	u32 reg;
 
-	reg = level << PRE_EMPHASIS_SET_SHIFT;
+	reg = readl(dp->reg_base + EXYNOS_DP_LN3_LINK_TRAINING_CTL);
+	reg &= ~PRE_EMPHASIS_SET_MASK;
+	reg |= level << PRE_EMPHASIS_SET_SHIFT;
 	writel(reg, dp->reg_base + EXYNOS_DP_LN3_LINK_TRAINING_CTL);
 }