6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Wayne Lin <Wayne.Lin@xxxxxxx> commit bfe79f5fff1300d96203383582b078c7b0aec80a upstream. [Why] For usb4 connector, AUX transaction is handled by dmub utilizing a differnt code path comparing to legacy DP connector. If the usb4 DP connector is disconnected, AUX access will report EBUSY and cause igt@kms_dp_aux_dev fail. [How] Align the error code with the one reported by legacy DP as EIO. Cc: Mario Limonciello <mario.limonciello@xxxxxxx> Cc: Alex Deucher <alexander.deucher@xxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Acked-by: Alex Hung <alex.hung@xxxxxxx> Signed-off-by: Wayne Lin <Wayne.Lin@xxxxxxx> Tested-by: Daniel Wheeler <daniel.wheeler@xxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c @@ -956,6 +956,11 @@ int dm_helper_dmub_aux_transfer_sync( struct aux_payload *payload, enum aux_return_code_type *operation_result) { + if (!link->hpd_status) { + *operation_result = AUX_RET_ERROR_HPD_DISCON; + return -1; + } + return amdgpu_dm_process_dmub_aux_transfer_sync(ctx, link->link_index, payload, operation_result); }