[PATCH 13/29] drm/i915/dp_mst: Add support to notify MST connectors to retry modesets

[Imre Deak]

Signed-off-by: Imre Deak <imre.deak at intel.com>
---
 .../drm/i915/display/intel_display_types.h    |  1 +
 drivers/gpu/drm/i915/display/intel_dp.c       | 19 ++++++++++++++++++-
 drivers/gpu/drm/i915/display/intel_dp.h       |  4 ++++
 .../drm/i915/display/intel_dp_link_training.c |  3 +--
 drivers/gpu/drm/i915/display/intel_dp_mst.c   |  3 +++
 drivers/gpu/drm/i915/display/intel_hotplug.c  |  7 ++++++-
 6 files changed, 33 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
index 3fdd8a5179831..dd30f8a328617 100644
--- a/drivers/gpu/drm/i915/display/intel_display_types.h
+++ b/drivers/gpu/drm/i915/display/intel_display_types.h
@@ -637,6 +637,7 @@ struct intel_connector {
 
 	/* Work struct to schedule a uevent on link train failure */
 	struct work_struct modeset_retry_work;
+	unsigned long modeset_retry_ref;
 
 	struct intel_hdcp hdcp;
 };
diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index b9487afe0f09f..9201623a4a3d9 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -2856,6 +2856,17 @@ intel_dp_audio_compute_config(struct intel_encoder *encoder,
 					intel_dp_is_uhbr(pipe_config);
 }
 
+void intel_dp_queue_modeset_retry_work(struct intel_connector *connector)
+{
+	struct drm_i915_private *i915 = to_i915(connector->base.dev);
+
+	if (test_and_set_bit(0, &connector->modeset_retry_ref))
+		return;
+
+	drm_connector_get(&connector->base);
+	queue_work(i915->unordered_wq, &connector->modeset_retry_work);
+}
+
 int
 intel_dp_compute_config(struct intel_encoder *encoder,
 			struct intel_crtc_state *pipe_config,
@@ -6434,7 +6445,7 @@ static bool intel_edp_init_connector(struct intel_dp *intel_dp,
 	return false;
 }
 
-static void intel_dp_modeset_retry_work_fn(struct work_struct *work)
+void intel_dp_modeset_retry_work_fn(struct work_struct *work)
 {
 	struct intel_connector *intel_connector;
 	struct drm_connector *connector;
@@ -6445,6 +6456,10 @@ static void intel_dp_modeset_retry_work_fn(struct work_struct *work)
 	drm_dbg_kms(connector->dev, "[CONNECTOR:%d:%s]\n", connector->base.id,
 		    connector->name);
 
+	if (drm_WARN_ON(connector->dev,
+			!test_and_clear_bit(0, &intel_connector->modeset_retry_ref)))
+		return;
+
 	/* Grab the locks before changing connector property*/
 	mutex_lock(&connector->dev->mode_config.mutex);
 	/* Set connector link status to BAD and send a Uevent to notify
@@ -6455,6 +6470,8 @@ static void intel_dp_modeset_retry_work_fn(struct work_struct *work)
 	mutex_unlock(&connector->dev->mode_config.mutex);
 	/* Send Hotplug uevent so userspace can reprobe */
 	drm_kms_helper_connector_hotplug_event(connector);
+
+	drm_connector_put(connector);
 }
 
 bool
diff --git a/drivers/gpu/drm/i915/display/intel_dp.h b/drivers/gpu/drm/i915/display/intel_dp.h
index 05db46b111f21..0993976c2e7cb 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.h
+++ b/drivers/gpu/drm/i915/display/intel_dp.h
@@ -23,6 +23,8 @@ struct intel_digital_port;
 struct intel_dp;
 struct intel_encoder;
 
+struct work_struct;
+
 struct link_config_limits {
 	int min_rate, max_rate;
 	int min_lane_count, max_lane_count;
@@ -43,6 +45,8 @@ void intel_dp_adjust_compliance_config(struct intel_dp *intel_dp,
 bool intel_dp_limited_color_range(const struct intel_crtc_state *crtc_state,
 				  const struct drm_connector_state *conn_state);
 int intel_dp_min_bpp(enum intel_output_format output_format);
+void intel_dp_modeset_retry_work_fn(struct work_struct *work);
+void intel_dp_queue_modeset_retry_work(struct intel_connector *connector);
 bool intel_dp_init_connector(struct intel_digital_port *dig_port,
 			     struct intel_connector *intel_connector);
 void intel_dp_set_link_params(struct intel_dp *intel_dp,
diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.c b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
index 1abfafbbfa757..7b140cbf8dd31 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
@@ -1075,7 +1075,6 @@ static void intel_dp_schedule_fallback_link_training(struct intel_dp *intel_dp,
 						     const struct intel_crtc_state *crtc_state)
 {
 	struct intel_connector *intel_connector = intel_dp->attached_connector;
-	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
 
 	if (!intel_digital_port_connected(&dp_to_dig_port(intel_dp)->base)) {
 		lt_dbg(intel_dp, DP_PHY_DPRX, "Link Training failed on disconnected sink.\n");
@@ -1093,7 +1092,7 @@ static void intel_dp_schedule_fallback_link_training(struct intel_dp *intel_dp,
 	}
 
 	/* Schedule a Hotplug Uevent to userspace to start modeset */
-	queue_work(i915->unordered_wq, &intel_connector->modeset_retry_work);
+	intel_dp_queue_modeset_retry_work(intel_connector);
 }
 
 /* Perform the link training on all LTTPRs and the DPRX on a link. */
diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
index 2b4432f7464a2..cad57ee44f6fb 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
@@ -1540,6 +1540,9 @@ static struct drm_connector *intel_dp_add_mst_connector(struct drm_dp_mst_topolo
 	intel_connector->port = port;
 	drm_dp_mst_get_port_malloc(port);
 
+	INIT_WORK(&intel_connector->modeset_retry_work,
+		  intel_dp_modeset_retry_work_fn);
+
 	intel_connector->dp.dsc_decompression_aux = drm_dp_mst_dsc_aux_for_port(port);
 	intel_dp_mst_read_decompression_port_dsc_caps(intel_dp, intel_connector);
 	intel_connector->dp.dsc_hblank_expansion_quirk =
diff --git a/drivers/gpu/drm/i915/display/intel_hotplug.c b/drivers/gpu/drm/i915/display/intel_hotplug.c
index 618d7a8c919ff..6edd9786d520d 100644
--- a/drivers/gpu/drm/i915/display/intel_hotplug.c
+++ b/drivers/gpu/drm/i915/display/intel_hotplug.c
@@ -869,8 +869,13 @@ static void intel_hpd_poll_fini(struct drm_i915_private *i915)
 	/* Kill all the work that may have been queued by hpd. */
 	drm_connector_list_iter_begin(&i915->drm, &conn_iter);
 	for_each_intel_connector_iter(connector, &conn_iter) {
-		if (connector->modeset_retry_work.func)
+		if (connector->modeset_retry_work.func) {
 			cancel_work_sync(&connector->modeset_retry_work);
+			if (connector->modeset_retry_ref) {
+				connector->modeset_retry_ref = false;
+				drm_connector_put(&connector->base);
+			}
+		}
 		if (connector->hdcp.shim) {
 			cancel_delayed_work_sync(&connector->hdcp.check_work);
 			cancel_work_sync(&connector->hdcp.prop_work);
-- 
2.39.2