drm/amd/display: Set LTTPR mode to non-LTTPR if no repeaters found

[WHY]
If no repeaters are found, we do not need or want to attempt to
link-train repeaters, as this could cause bugs.

Signed-off-by: Wesley Chalmers <Wesley.Chalmers@amd.com>
Acked-by: Bindu Ramamurthy <bindur12@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
index 9d6a8e728317c677319d28478238e34fe44bdd0a..e6f8f3c255bc983bd4082f99f694c614e0873672 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
@@ -3582,6 +3582,8 @@ static bool retrieve_link_cap(struct dc_link *link)
                                link->dpcd_caps.lttpr_caps.revision.raw >= 0x14);
                if (is_lttpr_present)
                        CONN_DATA_DETECT(link, lttpr_dpcd_data, sizeof(lttpr_dpcd_data), "LTTPR Caps: ");
+               else
+                       link->lttpr_mode = LTTPR_MODE_NON_LTTPR;
        }
 
        if (!is_lttpr_present)