video: tegra: dp: Fix CTS 700.1.1.2

CTS description: Additional DPCD handling
test 2

- Fix corrupted DPCD link capabilities

Bug 200103501

Change-Id: I7ebeb055284f73140a5f284bf8dc74da5662dc3d
Signed-off-by: Animesh Kishore <ankishore@nvidia.com>
Reviewed-on: http://git-master/r/785852
(cherry picked from commit 10228ba705d70ded2d52d95524e173d1bb9198b9)
Reviewed-on: http://git-master/r/812198
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Bitan Biswas <bbiswas@nvidia.com>

1 files changed, 16 insertions, 0 deletions

diff --git a/drivers/video/tegra/dc/dp.c b/drivers/video/tegra/dc/dp.c
index 03bab4c5c..7ea1dfb2c 100644
--- a/drivers/video/tegra/dc/dp.c
+++ b/drivers/video/tegra/dc/dp.c
@@ -1543,6 +1543,14 @@ static int tegra_dp_init_max_link_cfg(struct tegra_dc_dp_data *dp,
                                 NV_DPCD_MAX_LANE_COUNT, &dpcd_data));
 
                 cfg->max_lane_count = dpcd_data & NV_DPCD_MAX_LANE_COUNT_MASK;
+
+                if (cfg->max_lane_count >= 4)
+                        cfg->max_lane_count = 4;
+                else if (cfg->max_lane_count >= 2)
+                        cfg->max_lane_count = 2;
+                else
+                        cfg->max_lane_count = 1;
+
                 if (dp->pdata && dp->pdata->lanes &&
                         dp->pdata->lanes < cfg->max_lane_count)
                         cfg->max_lane_count = dp->pdata->lanes;
@@ -1578,6 +1586,14 @@ static int tegra_dp_init_max_link_cfg(struct tegra_dc_dp_data *dp,
                         CHECK_RET(tegra_dc_dp_dpcd_read(dp,
                                 NV_DPCD_MAX_LINK_BANDWIDTH,
                                 &cfg->max_link_bw));
+
+                if (cfg->max_link_bw >= SOR_LINK_SPEED_G5_4)
+                        cfg->max_link_bw = SOR_LINK_SPEED_G5_4;
+                else if (cfg->max_link_bw >= SOR_LINK_SPEED_G2_7)
+                        cfg->max_link_bw = SOR_LINK_SPEED_G2_7;
+                else
+                        cfg->max_link_bw = SOR_LINK_SPEED_G1_62;
+
                 if (dp->pdata && dp->pdata->link_bw &&
                         dp->pdata->link_bw < cfg->max_link_bw)
                         cfg->max_link_bw = dp->pdata->link_bw;