From: Peichen Huang <[email protected]> [WHY] User may connect mst dock with multi monitors and do quick unplug and plug in one of the monitor. This operatioin may create CSN from dock to display driver. Then display driver would disable and then enable mst link and also disable/enable DPCD mst_en bit in dock RX. However, when mst_en bit being disabled, if dock has another CSN message to transmit then the message would be removed because of the disabling of mst_en. In this case, the message is missing and it ends up no display in the replugged monitor.
[HOW] Don't disable mst_en bit when link still has sink connected. Reviewed-by: Wenjing Liu <[email protected]> Signed-off-by: Peichen Huang <[email protected]> Signed-off-by: Chenyu Chen <[email protected]> --- drivers/gpu/drm/amd/display/dc/link/link_dpms.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/amd/display/dc/link/link_dpms.c b/drivers/gpu/drm/amd/display/dc/link/link_dpms.c index 87f9ceebe26a..7384676e646d 100644 --- a/drivers/gpu/drm/amd/display/dc/link/link_dpms.c +++ b/drivers/gpu/drm/amd/display/dc/link/link_dpms.c @@ -1931,7 +1931,7 @@ static void disable_link_dp(struct dc_link *link, link->dc->hwss.edp_power_control(link, false); } - if (signal == SIGNAL_TYPE_DISPLAY_PORT_MST) + if (signal == SIGNAL_TYPE_DISPLAY_PORT_MST && link->sink_count == 0) /* set the sink to SST mode after disabling the link */ enable_mst_on_sink(link, false); @@ -2082,7 +2082,12 @@ static enum dc_status enable_link_dp(struct dc_state *state, pipe_ctx->stream->signal == SIGNAL_TYPE_DISPLAY_PORT && link->dc->debug.set_mst_en_for_sst) { enable_mst_on_sink(link, true); + } else if (link->dpcd_caps.is_mst_capable && + pipe_ctx->stream->signal == SIGNAL_TYPE_DISPLAY_PORT) { + /* disable mst on sink */ + enable_mst_on_sink(link, false); } + if (pipe_ctx->stream->signal == SIGNAL_TYPE_EDP) { /*in case it is not on*/ if (!link->dc->config.edp_no_power_sequencing) @@ -2368,9 +2373,9 @@ void link_set_dpms_off(struct pipe_ctx *pipe_ctx) if (pipe_ctx->stream->sink) { if (pipe_ctx->stream->sink->sink_signal != SIGNAL_TYPE_VIRTUAL && pipe_ctx->stream->sink->sink_signal != SIGNAL_TYPE_NONE) { - DC_LOG_DC("%s pipe_ctx dispname=%s signal=%x link=%d\n", __func__, + DC_LOG_DC("%s pipe_ctx dispname=%s signal=%x link=%d sink_count=%d\n", __func__, pipe_ctx->stream->sink->edid_caps.display_name, - pipe_ctx->stream->signal, link->link_index); + pipe_ctx->stream->signal, link->link_index, link->sink_count); } } @@ -2484,10 +2489,11 @@ void link_set_dpms_on( if (pipe_ctx->stream->sink) { if (pipe_ctx->stream->sink->sink_signal != SIGNAL_TYPE_VIRTUAL && pipe_ctx->stream->sink->sink_signal != SIGNAL_TYPE_NONE) { - DC_LOG_DC("%s pipe_ctx dispname=%s signal=%x link=%d\n", __func__, + DC_LOG_DC("%s pipe_ctx dispname=%s signal=%x link=%d sink_count=%d\n", __func__, pipe_ctx->stream->sink->edid_caps.display_name, pipe_ctx->stream->signal, - link->link_index); + link->link_index, + link->sink_count); } } -- 2.43.0
