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).

Fixes: 2e0adc765d88 ("drm/msm/dp: do not end dp link training until video is 
ready")
Signed-off-by: Kuogee Hsieh <quic_khs...@quicinc.com>
---
 drivers/gpu/drm/msm/dp/dp_ctrl.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c
index 39558a2..3e4b3d9 100644
--- a/drivers/gpu/drm/msm/dp/dp_ctrl.c
+++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c
@@ -1745,6 +1745,9 @@ 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);
                }
        }
 
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