This is a note to let you know that I've just added the patch titled drm/msm/dp: delete DP_RECOVERED_CLOCK_OUT_EN to fix tps4 to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-msm-dp-delete-dp_recovered_clock_out_en-to-fix-t.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 24257d08156d3edba786239603006bb359ec22d6 Author: Kuogee Hsieh <quic_khsieh@xxxxxxxxxxx> Date: Thu Aug 11 15:57:50 2022 -0700 drm/msm/dp: delete DP_RECOVERED_CLOCK_OUT_EN to fix tps4 [ Upstream commit 032d57960176ac01cc5adff5bcc5eb51317f8781 ] 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@xxxxxxxxxxx> Reviewed-by: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx> Reviewed-by: Stephen Boyd <swboyd@xxxxxxxxxxxx> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> Patchwork: https://patchwork.freedesktop.org/patch/497194/ Link: https://lore.kernel.org/r/1660258670-4200-1-git-send-email-quic_khsieh@xxxxxxxxxxx Signed-off-by: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c index b9ca844ce2ad0..9fac55c24214a 100644 --- a/drivers/gpu/drm/msm/dp/dp_ctrl.c +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c @@ -1205,7 +1205,7 @@ 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->panel->dpcd);