From: Kuogee Hsieh Date: Tue, 18 Jan 2022 18:47:28 +0000 (-0800) Subject: drm/msm/dp: stop link training after link training 2 failed X-Git-Tag: Ubuntu-5.15.0-29.30~1158 X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=83910a0f6218238c91a48262f0586aca75e9e6a0;p=mirror_ubuntu-jammy-kernel.git drm/msm/dp: stop link training after link training 2 failed BugLink: https://bugs.launchpad.net/bugs/1969110 [ Upstream commit 9051d629dbf7a998a40f7eac65a9512b01bc3bb8 ] Each DP link training contains link training 1 followed by link training 2. There is maximum of 5 retries of DP link training before declared link training failed. It is required to stop link training at end of link training 2 if it is failed so that next link training 1 can start freshly. This patch fixes link compliance test case 4.3.1.13 (Source Device Link Training EQ Fallback Test). Changes in v10: -- group into one series Changes in v11: -- drop drm/msm/dp: dp_link_parse_sink_count() return immediately if aux read Fixes: 2e0adc765d88 ("drm/msm/dp: do not end dp link training until video is ready") Signed-off-by: Kuogee Hsieh Reviewed-by: Stephen Boyd Link: https://lore.kernel.org/r/1642531648-8448-5-git-send-email-quic_khsieh@quicinc.com Signed-off-by: Dmitry Baryshkov Signed-off-by: Sasha Levin (cherry picked from commit 740d2330760e710240c9d89e191686a1d148dda2) Signed-off-by: Paolo Pisati --- diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c index 62e75dc8afc6..4af281d97493 100644 --- a/drivers/gpu/drm/msm/dp/dp_ctrl.c +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c @@ -1744,6 +1744,9 @@ int dp_ctrl_on_link(struct dp_ctrl *dp_ctrl) /* end with failure */ break; /* lane == 1 already */ } + + /* stop link training before start re training */ + dp_ctrl_clear_training_pattern(ctrl); } }