6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Wayne Lin <wayne.lin@xxxxxxx> commit 9cdef4f720376ef0fb0febce1ed2377c19e531f9 upstream. link_rate sometime will be changed when DP MST connector hotplug, so pbn_div also need be updated; otherwise, it will mismatch with link_rate, causes no output in external monitor. This is a backport to 6.7 and older. Cc: stable@xxxxxxxxxxxxxxx Tested-by: Daniel Wheeler <daniel.wheeler@xxxxxxx> Reviewed-by: Jerry Zuo <jerry.zuo@xxxxxxx> Acked-by: Rodrigo Siqueira <rodrigo.siqueira@xxxxxxx> Signed-off-by: Wade Wang <wade.wang@xxxxxx> Signed-off-by: Wayne Lin <wayne.lin@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.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -6868,8 +6868,7 @@ static int dm_encoder_helper_atomic_chec if (IS_ERR(mst_state)) return PTR_ERR(mst_state); - if (!mst_state->pbn_div) - mst_state->pbn_div = dm_mst_get_pbn_divider(aconnector->mst_root->dc_link); + mst_state->pbn_div = dm_mst_get_pbn_divider(aconnector->mst_root->dc_link); if (!state->duplicated) { int max_bpc = conn_state->max_requested_bpc;