This is a note to let you know that I've just added the patch titled drm/msm/dp: check sink_count before update is_connected status to the 5.12-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-msm-dp-check-sink_count-before-update-is_connected-status.patch and it can be found in the queue-5.12 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From d9aa6571b28ba0022de1e48801ff03a1854c7ef2 Mon Sep 17 00:00:00 2001 From: Kuogee Hsieh <khsieh@xxxxxxxxxxxxxx> Date: Wed, 21 Apr 2021 16:37:35 -0700 Subject: drm/msm/dp: check sink_count before update is_connected status From: Kuogee Hsieh <khsieh@xxxxxxxxxxxxxx> commit d9aa6571b28ba0022de1e48801ff03a1854c7ef2 upstream. Link status is different from display connected status in the case of something like an Apple dongle where the type-c plug can be connected, and therefore the link is connected, but no sink is connected until an HDMI cable is plugged into the dongle. The sink_count of DPCD of dongle will increase to 1 once an HDMI cable is plugged into the dongle so that display connected status will become true. This checking also apply at pm_resume. Changes in v4: -- none Fixes: 94e58e2d06e3 ("drm/msm/dp: reset dp controller only at boot up and pm_resume") Reported-by: Stephen Boyd <swboyd@xxxxxxxxxxxx> Reviewed-by: Stephen Boyd <swboyd@xxxxxxxxxxxx> Tested-by: Stephen Boyd <swboyd@xxxxxxxxxxxx> Signed-off-by: Kuogee Hsieh <khsieh@xxxxxxxxxxxxxx> Fixes: 8ede2ecc3e5e ("drm/msm/dp: Add DP compliance tests on Snapdragon Chipsets") Link: https://lore.kernel.org/r/1619048258-8717-2-git-send-email-khsieh@xxxxxxxxxxxxxx Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/msm/dp/dp_display.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) --- a/drivers/gpu/drm/msm/dp/dp_display.c +++ b/drivers/gpu/drm/msm/dp/dp_display.c @@ -595,10 +595,8 @@ static int dp_connect_pending_timeout(st mutex_lock(&dp->event_mutex); state = dp->hpd_state; - if (state == ST_CONNECT_PENDING) { - dp_display_enable(dp, 0); + if (state == ST_CONNECT_PENDING) dp->hpd_state = ST_CONNECTED; - } mutex_unlock(&dp->event_mutex); @@ -677,10 +675,8 @@ static int dp_disconnect_pending_timeout mutex_lock(&dp->event_mutex); state = dp->hpd_state; - if (state == ST_DISCONNECT_PENDING) { - dp_display_disable(dp, 0); + if (state == ST_DISCONNECT_PENDING) dp->hpd_state = ST_DISCONNECTED; - } mutex_unlock(&dp->event_mutex); @@ -1279,7 +1275,12 @@ static int dp_pm_resume(struct device *d status = dp_catalog_link_is_connected(dp->catalog); - if (status) + /* + * can not declared display is connected unless + * HDMI cable is plugged in and sink_count of + * dongle become 1 + */ + if (status && dp->link->sink_count) dp->dp_display.is_connected = true; else dp->dp_display.is_connected = false; Patches currently in stable-queue which might be from khsieh@xxxxxxxxxxxxxx are queue-5.12/drm-msm-dp-initialize-audio_comp-when-audio-starts.patch queue-5.12/drm-msm-dp-check-sink_count-before-update-is_connected-status.patch