From: Ilya Bakoulin Ilya.Bakoulin@amd.com
[ Upstream commit e8bffa52e0253cfd689813a620e64521256bc712 ]
[Why] Setting link DPMS off in response to HPD disconnect creates AUX transactions on a link that is supposed to be disconnected. This can cause issues in some cases when the sink re-asserts HPD and expects source to re-enable the link.
[How] Avoid AUX transactions on disconnected link.
Reviewed-by: Wenjing Liu wenjing.liu@amd.com Signed-off-by: Ilya Bakoulin Ilya.Bakoulin@amd.com Signed-off-by: Aurabindo Pillai aurabindo.pillai@amd.com Tested-by: Daniel Wheeler daniel.wheeler@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- .../gpu/drm/amd/display/dc/link/protocols/link_dp_phy.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_phy.c b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_phy.c index 9bde0c8bf914a..f01a3df584552 100644 --- a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_phy.c +++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_phy.c @@ -74,7 +74,8 @@ void dp_disable_link_phy(struct dc_link *link, struct dc *dc = link->ctx->dc;
if (!link->wa_flags.dp_keep_receiver_powered && - !link->skip_implict_edp_power_control) + !link->skip_implict_edp_power_control && + link->type != dc_connection_none) dpcd_write_rx_power_ctrl(link, false);
dc->hwss.disable_link_output(link, link_res, signal); @@ -159,8 +160,9 @@ enum dc_status dp_set_fec_ready(struct dc_link *link, const struct link_resource } else { if (link->fec_state == dc_link_fec_ready) { fec_config = 0; - core_link_write_dpcd(link, DP_FEC_CONFIGURATION, - &fec_config, sizeof(fec_config)); + if (link->type != dc_connection_none) + core_link_write_dpcd(link, DP_FEC_CONFIGURATION, + &fec_config, sizeof(fec_config));
link_enc->funcs->fec_set_ready(link_enc, false); link->fec_state = dc_link_fec_not_ready;