1 files changed, 46 insertions, 26 deletions

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 81f10ab5890b..01b9f181727c 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -4582,6 +4582,16 @@ intel_dp_long_pulse(struct intel_connector *intel_connector)
 		 */
 		status = connector_status_disconnected;
 		goto out;
+	} else if (connector->status == connector_status_connected) {
+		/*
+		 * If display was connected already and is still connected
+		 * check links status, there has been known issues of
+		 * link loss triggerring long pulse!!!!
+		 */
+		drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
+		intel_dp_check_link_status(intel_dp);
+		drm_modeset_unlock(&dev->mode_config.connection_mutex);
+		goto out;
 	}
 
 	/*
@@ -4595,6 +4605,7 @@ intel_dp_long_pulse(struct intel_connector *intel_connector)
 	intel_dp_set_edid(intel_dp);
 
 	status = connector_status_connected;
+	intel_dp->detect_done = true;
 
 	/* Try to read the source of the interrupt */
 	if (intel_dp->dpcd[DP_DPCD_REV] >= 0x11 &&
@@ -4611,8 +4622,21 @@ intel_dp_long_pulse(struct intel_connector *intel_connector)
 	}
 
 out:
-	if (status != connector_status_connected)
+	if (status != connector_status_connected) {
 		intel_dp_unset_edid(intel_dp);
+		/*
+		 * If we were in MST mode, and device is not there,
+		 * get out of MST mode
+		 */
+		if (intel_dp->is_mst) {
+			DRM_DEBUG_KMS("MST device may have disappeared %d vs %d\n",
+				      intel_dp->is_mst, intel_dp->mst_mgr.mst_state);
+			intel_dp->is_mst = false;
+			drm_dp_mst_topology_mgr_set_mst(&intel_dp->mst_mgr,
+							intel_dp->is_mst);
+		}
+	}
+
 	intel_display_power_put(to_i915(dev), power_domain);
 	return;
 }
@@ -4636,7 +4660,11 @@ intel_dp_detect(struct drm_connector *connector, bool force)
 		return connector_status_disconnected;
 	}
 
-	intel_dp_long_pulse(intel_dp->attached_connector);
+	/* If full detect is not performed yet, do a full detect */
+	if (!intel_dp->detect_done)
+		intel_dp_long_pulse(intel_dp->attached_connector);
+
+	intel_dp->detect_done = false;
 
 	if (intel_connector->detect_edid)
 		return connector_status_connected;
@@ -4968,25 +4996,25 @@ intel_dp_hpd_pulse(struct intel_digital_port *intel_dig_port, bool long_hpd)
 		/* indicate that we need to restart link training */
 		intel_dp->train_set_valid = false;
 
-		if (!intel_digital_port_connected(dev_priv, intel_dig_port))
-			goto mst_fail;
-
-		if (!intel_dp_get_dpcd(intel_dp)) {
-			goto mst_fail;
-		}
-
-		intel_dp_probe_oui(intel_dp);
+		intel_dp_long_pulse(intel_dp->attached_connector);
+		if (intel_dp->is_mst)
+			ret = IRQ_HANDLED;
+		goto put_power;
 
-		if (!intel_dp_probe_mst(intel_dp)) {
-			drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
-			intel_dp_check_link_status(intel_dp);
-			drm_modeset_unlock(&dev->mode_config.connection_mutex);
-			goto mst_fail;
-		}
 	} else {
 		if (intel_dp->is_mst) {
-			if (intel_dp_check_mst_status(intel_dp) == -EINVAL)
-				goto mst_fail;
+			if (intel_dp_check_mst_status(intel_dp) == -EINVAL) {
+				/*
+				 * If we were in MST mode, and device is not
+				 * there, get out of MST mode
+				 */
+				DRM_DEBUG_KMS("MST device may have disappeared %d vs %d\n",
+					      intel_dp->is_mst, intel_dp->mst_mgr.mst_state);
+				intel_dp->is_mst = false;
+				drm_dp_mst_topology_mgr_set_mst(&intel_dp->mst_mgr,
+								intel_dp->is_mst);
+				goto put_power;
+			}
 		}
 
 		if (!intel_dp->is_mst) {
@@ -4998,14 +5026,6 @@ intel_dp_hpd_pulse(struct intel_digital_port *intel_dig_port, bool long_hpd)
 
 	ret = IRQ_HANDLED;
 
-	goto put_power;
-mst_fail:
-	/* if we were in MST mode, and device is not there get out of MST mode */
-	if (intel_dp->is_mst) {
-		DRM_DEBUG_KMS("MST device may have disappeared %d vs %d\n", intel_dp->is_mst, intel_dp->mst_mgr.mst_state);
-		intel_dp->is_mst = false;
-		drm_dp_mst_topology_mgr_set_mst(&intel_dp->mst_mgr, intel_dp->is_mst);
-	}
 put_power:
 	intel_display_power_put(dev_priv, power_domain);