[PATCH 04/10] video: exynos_dp: Get pll lock before pattern set
flat view
STALE5180d
REVIEWED: 1 (0M)
From: Sean Paul <hidden>
Date: 2012-08-08 03:54:18
Subsystem:
framebuffer layer, the rest · Maintainers:
Helge Deller, Linus Torvalds
Status: Reviewed.
1 review trailer.
According to the exynos datasheet (Figure 49-10), we should wait for PLL lock before programming the training pattern when doing software eDP link training. Signed-off-by: Sean Paul <redacted> Reviewed-by: Mandeep Singh Baines <redacted> --- drivers/video/exynos/exynos_dp_core.c | 14 +++++++++++++- 1 files changed, 13 insertions(+), 1 deletions(-)
diff --git a/drivers/video/exynos/exynos_dp_core.c b/drivers/video/exynos/exynos_dp_core.c
index 3deded2..207bd7e 100644
--- a/drivers/video/exynos/exynos_dp_core.c
+++ b/drivers/video/exynos/exynos_dp_core.c@@ -23,6 +23,8 @@ #include "exynos_dp_core.h" +#define PLL_MAX_TRIES 100 + static int exynos_dp_init_dp(struct exynos_dp_device *dp) { exynos_dp_reset(dp);
@@ -260,7 +262,7 @@ static void exynos_dp_set_lane_lane_pre_emphasis(struct exynos_dp_device *dp, static int exynos_dp_link_start(struct exynos_dp_device *dp) { - int ret, lane, lane_count; + int ret, lane, lane_count, pll_tries; u8 buf[4]; lane_count = dp->link_train.lane_count;
@@ -293,6 +295,16 @@ static int exynos_dp_link_start(struct exynos_dp_device *dp) exynos_dp_set_lane_lane_pre_emphasis(dp, PRE_EMPHASIS_LEVEL_0, lane); + /* Wait for PLL lock */ + pll_tries = 0; + while (exynos_dp_get_pll_lock_status(dp) = PLL_UNLOCKED) { + if (pll_tries = PLL_MAX_TRIES) + return -ETIMEDOUT; + + pll_tries++; + udelay(100); + } + /* Set training pattern 1 */ exynos_dp_set_training_pattern(dp, TRAINING_PTN1);
--
1.7.7.3