From 8f28be4204171ded93611363911982d34d9b6e60 Mon Sep 17 00:00:00 2001
From: Kuogee Hsieh <quic_khsieh@quicinc.com>
Date: Thu, 11 Aug 2022 15:57:50 -0700
Subject: drm/msm/dp: delete DP_RECOVERED_CLOCK_OUT_EN to fix tps4
Git-commit: 032d57960176ac01cc5adff5bcc5eb51317f8781
Patch-mainline: v6.0-rc4
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225 jsc#PED-2849
Alt-commit: 3487896b26269f5430596711490a7c48d2941d9d
Data Symbols scrambled is required for tps4 at link training 2.
Therefore SCRAMBLING_DISABLE bit should not be set for tps4 to
work.
RECOVERED_CLOCK_OUT_EN is for enable simple EYE test for jitter
measurement with minimal equipment for embedded applications purpose
and is not required to be set during normal operation. Current
implementation always have RECOVERED_CLOCK_OUT_EN bit set which
cause SCRAMBLING_DISABLE bit wrongly set at tps4 which prevent
tps4 from working.
This patch delete setting RECOVERED_CLOCK_OUT_EN to fix
SCRAMBLING_DISABLE be wrongly set at tps4.
Changes in v2:
-- fix Fixes tag
Changes in v3:
-- revise commit text
Changes in v4:
-- fix commit text newline
Changes in v5:
-- fix commit text line over 75 chars
Fixes: c943b4948b58 ("drm/msm/dp: add displayPort driver support")
Signed-off-by: Kuogee Hsieh <quic_khsieh@quicinc.com>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/497194/
Link: https://lore.kernel.org/r/1660258670-4200-1-git-send-email-quic_khsieh@quicinc.com
Signed-off-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/msm/dp/dp_ctrl.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c
index ab6aa13b1639..013ca02e17cb 100644
--- a/drivers/gpu/drm/msm/dp/dp_ctrl.c
+++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c
@@ -1214,7 +1214,7 @@ static int dp_ctrl_link_train_2(struct dp_ctrl_private *ctrl,
if (ret)
return ret;
- dp_ctrl_train_pattern_set(ctrl, pattern | DP_RECOVERED_CLOCK_OUT_EN);
+ dp_ctrl_train_pattern_set(ctrl, pattern);
for (tries = 0; tries <= maximum_retries; tries++) {
drm_dp_link_train_channel_eq_delay(ctrl->aux, ctrl->panel->dpcd);
--
2.38.1