On Tue 28 Dec 10:51 PST 2021, Kuogee Hsieh wrote:

From: Kuogee Hsieh khsieh@codeaurora.org

Some DP sinkers prefer to use tps4 instead of tps3 during training #2. This patch will use tps4 to perform link training #2 if sinker's DPCD supports it.

Signed-off-by: Kuogee Hsieh quic_khsieh@quicinc.com

drivers/gpu/drm/msm/dp/dp_ctrl.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c index 39558a2..c7b0657 100644 --- a/drivers/gpu/drm/msm/dp/dp_ctrl.c +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c @@ -1181,7 +1181,7 @@ static int dp_ctrl_link_train_2(struct dp_ctrl_private *ctrl, int *training_step) { int tries = 0, ret = 0;

• char pattern;

• char pattern, state_ctrl_bit; int const maximum_retries = 5; u8 link_status[DP_LINK_STATUS_SIZE];

@@ -1189,12 +1189,20 @@ static int dp_ctrl_link_train_2(struct dp_ctrl_private *ctrl,

*training_step = DP_TRAINING_2;

• if (drm_dp_tps3_supported(ctrl->panel->dpcd))

• if (drm_dp_tps4_supported(ctrl->panel->dpcd)) {

• pattern = DP_TRAINING_PATTERN_4;
  

• state_ctrl_bit = 4;
  

• }
• else if (drm_dp_tps3_supported(ctrl->panel->dpcd)) { pattern = DP_TRAINING_PATTERN_3;

• else

• state_ctrl_bit = 3;
  

• }
• else { pattern = DP_TRAINING_PATTERN_2;

• state_ctrl_bit = 2;
  

• }

• ret = dp_catalog_ctrl_set_pattern(ctrl->catalog, pattern);

• ret = dp_catalog_ctrl_set_pattern(ctrl->catalog, state_ctrl_bit);

The patch looks good, but as the state_ctrl_bit is no longer equal to DP_PATTERN_n the function and argument names are misleading.

Please rename it to something like "dp_catalog_ctrl_set_pattern_state_bit()" and the "pattern" argument within that function to "state_bit".

Thanks, Bjorn

if (ret) return ret;

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