[PATCH 5/5] drm/msm/dp: mark the SST connector disconnected when MST is enabled

Yongxing Mou yongxing.mou at oss.qualcomm.com
Mon Jun 29 07:48:07 PDT 2026


When MST becomes active, the initial HPD plug notification updates the
SST connector state to connected.

However, the subsequent SST connector detect path reports disconnected
while MST is enabled. This connected -> disconnected transition is then
observed by the polling logic and may result in an unnecessary hotplug
event.

Set the SST connector state to disconnected immediately after MST is
initialized so that the detect path does not introduce a transient
state change.

Signed-off-by: Yongxing Mou <yongxing.mou at oss.qualcomm.com>
---
 drivers/gpu/drm/msm/dp/dp_display.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
index 4ee391cc7165..f8ca60d6d714 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -352,8 +352,10 @@ static int msm_dp_display_process_hpd_high(struct msm_dp_display_private *dp)
 	if (dp->max_stream > 1 && drm_dp_read_mst_cap(dp->aux, dp->panel->dpcd))
 		msm_dp_display_mst_init(dp);
 
-	if (dp->msm_dp_display.mst_active)
+	if (dp->msm_dp_display.mst_active) {
+		connector->status = connector_status_disconnected;
 		msm_dp_mst_display_set_mgr_state(&dp->msm_dp_display, true);
+	}
 
 	msm_dp_link_reset_phy_params_vx_px(dp->link);
 

-- 
2.43.0




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