From: Aurabindo Pillai aurabindo.pillai@amd.com

[ Upstream commit e6142dd511425cb827b5db869f489eb81f5f994d ]

[why] During hotplug, a DP port may be connected to the sink through passive adapter which does not support DPCD reads. Issuing reads without checking for this condition will result in errors

[how] Ensure the link is in aux_mode before initiating operation that result in a DPCD read.

Signed-off-by: Aurabindo Pillai aurabindo.pillai@amd.com Reviewed-by: Harry Wentland Harry.Wentland@amd.com Acked-by: Aurabindo Pillai aurabindo.pillai@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c index 8136a58deb393..f98c42150b4f3 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -1941,17 +1941,22 @@ amdgpu_dm_update_connector_after_detect(struct amdgpu_dm_connector *aconnector) dc_sink_retain(aconnector->dc_sink); if (sink->dc_edid.length == 0) { aconnector->edid = NULL; - drm_dp_cec_unset_edid(&aconnector->dm_dp_aux.aux); + if (aconnector->dc_link->aux_mode) { + drm_dp_cec_unset_edid( + &aconnector->dm_dp_aux.aux); + } } else { aconnector->edid = - (struct edid *) sink->dc_edid.raw_edid; - + (struct edid *)sink->dc_edid.raw_edid;

drm_connector_update_edid_property(connector, - aconnector->edid); - drm_dp_cec_set_edid(&aconnector->dm_dp_aux.aux, - aconnector->edid); + aconnector->edid); + + if (aconnector->dc_link->aux_mode) + drm_dp_cec_set_edid(&aconnector->dm_dp_aux.aux, + aconnector->edid); } + amdgpu_dm_update_freesync_caps(connector, aconnector->edid);

} else {