drm/i915: Add a retry counter for hotplug detect retries

On TypeC connectors we need to retry the detection after hotplug events
for a longer time, so add a retry counter to support this. The next
patch will add detection retries on TypeC ports needing this.
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200330095425.29113-1-imre.deak@intel.com

drivers/gpu/drm/i915/display/intel_ddi.c

@@ -4518,15 +4518,14 @@ static int intel_hdmi_reset_link(struct intel_encoder *encoder,
 
 static enum intel_hotplug_state
 intel_ddi_hotplug(struct intel_encoder *encoder,
-		  struct intel_connector *connector,
-		  bool irq_received)
+		  struct intel_connector *connector)
 {
 	struct intel_digital_port *dig_port = enc_to_dig_port(encoder);
 	struct drm_modeset_acquire_ctx ctx;
 	enum intel_hotplug_state state;
 	int ret;
 
-	state = intel_encoder_hotplug(encoder, connector, irq_received);
+	state = intel_encoder_hotplug(encoder, connector);
 
 	drm_modeset_acquire_init(&ctx, 0);
 
@@ -4565,7 +4564,7 @@ intel_ddi_hotplug(struct intel_encoder *encoder,
 	 * time around we didn't detect any change in the sink's connection
 	 * status.
 	 */
-	if (state == INTEL_HOTPLUG_UNCHANGED && irq_received &&
+	if (state == INTEL_HOTPLUG_UNCHANGED && !connector->hotplug_retries &&
 	    !dig_port->dp.is_mst)
 		state = INTEL_HOTPLUG_RETRY;
 

drivers/gpu/drm/i915/display/intel_display_types.h

@@ -132,8 +132,7 @@ struct intel_encoder {
 	u16 cloneable;
 	u8 pipe_mask;
 	enum intel_hotplug_state (*hotplug)(struct intel_encoder *encoder,
-					    struct intel_connector *connector,
-					    bool irq_received);
+					    struct intel_connector *connector);
 	enum intel_output_type (*compute_output_type)(struct intel_encoder *,
 						      struct intel_crtc_state *,
 						      struct drm_connector_state *);
@@ -432,6 +431,9 @@ struct intel_connector {
 	struct edid *edid;
 	struct edid *detect_edid;
 
+	/* Number of times hotplug detection was tried after an HPD interrupt */
+	int hotplug_retries;
+
 	/* since POLL and HPD connectors may use the same HPD line keep the native
 	   state of connector->polled in case hotplug storm detection changes it */
 	u8 polled;

drivers/gpu/drm/i915/display/intel_dp.c

@@ -5571,14 +5571,13 @@ int intel_dp_retrain_link(struct intel_encoder *encoder,
  */
 static enum intel_hotplug_state
 intel_dp_hotplug(struct intel_encoder *encoder,
-		 struct intel_connector *connector,
-		 bool irq_received)
+		 struct intel_connector *connector)
 {
 	struct drm_modeset_acquire_ctx ctx;
 	enum intel_hotplug_state state;
 	int ret;
 
-	state = intel_encoder_hotplug(encoder, connector, irq_received);
+	state = intel_encoder_hotplug(encoder, connector);
 
 	drm_modeset_acquire_init(&ctx, 0);
 
@@ -5602,7 +5601,7 @@ intel_dp_hotplug(struct intel_encoder *encoder,
 	 * Keeping it consistent with intel_ddi_hotplug() and
 	 * intel_hdmi_hotplug().
 	 */
-	if (state == INTEL_HOTPLUG_UNCHANGED && irq_received)
+	if (state == INTEL_HOTPLUG_UNCHANGED && !connector->hotplug_retries)
 		state = INTEL_HOTPLUG_RETRY;
 
 	return state;

drivers/gpu/drm/i915/display/intel_hdmi.c

@@ -3279,11 +3279,11 @@ void intel_hdmi_init_connector(struct intel_digital_port *intel_dig_port,
 
 static enum intel_hotplug_state
 intel_hdmi_hotplug(struct intel_encoder *encoder,
-		   struct intel_connector *connector, bool irq_received)
+		   struct intel_connector *connector)
 {
 	enum intel_hotplug_state state;
 
-	state = intel_encoder_hotplug(encoder, connector, irq_received);
+	state = intel_encoder_hotplug(encoder, connector);
 
 	/*
 	 * On many platforms the HDMI live state signal is known to be
@@ -3297,7 +3297,7 @@ intel_hdmi_hotplug(struct intel_encoder *encoder,
 	 * time around we didn't detect any change in the sink's connection
 	 * status.
 	 */
-	if (state == INTEL_HOTPLUG_UNCHANGED && irq_received)
+	if (state == INTEL_HOTPLUG_UNCHANGED && !connector->hotplug_retries)
 		state = INTEL_HOTPLUG_RETRY;
 
 	return state;

drivers/gpu/drm/i915/display/intel_hotplug.c

@@ -270,8 +270,7 @@ static void intel_hpd_irq_storm_reenable_work(struct work_struct *work)
 
 enum intel_hotplug_state
 intel_encoder_hotplug(struct intel_encoder *encoder,
-		      struct intel_connector *connector,
-		      bool irq_received)
+		      struct intel_connector *connector)
 {
 	struct drm_device *dev = connector->base.dev;
 	enum drm_connector_status old_status;
@@ -392,12 +391,17 @@ static void i915_hotplug_work_func(struct work_struct *work)
 			struct intel_encoder *encoder =
 				intel_attached_encoder(connector);
 
+			if (hpd_event_bits & hpd_bit)
+				connector->hotplug_retries = 0;
+			else
+				connector->hotplug_retries++;
+
 			drm_dbg_kms(&dev_priv->drm,
-				    "Connector %s (pin %i) received hotplug event.\n",
-				    connector->base.name, pin);
+				    "Connector %s (pin %i) received hotplug event. (retry %d)\n",
+				    connector->base.name, pin,
+				    connector->hotplug_retries);
 
-			switch (encoder->hotplug(encoder, connector,
-						 hpd_event_bits & hpd_bit)) {
+			switch (encoder->hotplug(encoder, connector)) {
 			case INTEL_HOTPLUG_UNCHANGED:
 				break;
 			case INTEL_HOTPLUG_CHANGED:

drivers/gpu/drm/i915/display/intel_hotplug.h

@@ -15,8 +15,7 @@ enum port;
 
 void intel_hpd_poll_init(struct drm_i915_private *dev_priv);
 enum intel_hotplug_state intel_encoder_hotplug(struct intel_encoder *encoder,
-					       struct intel_connector *connector,
-					       bool irq_received);
+					       struct intel_connector *connector);
 void intel_hpd_irq_handler(struct drm_i915_private *dev_priv,
 			   u32 pin_mask, u32 long_mask);
 void intel_hpd_init(struct drm_i915_private *dev_priv);

drivers/gpu/drm/i915/display/intel_sdvo.c

@@ -1939,12 +1939,11 @@ static void intel_sdvo_enable_hotplug(struct intel_encoder *encoder)
 
 static enum intel_hotplug_state
 intel_sdvo_hotplug(struct intel_encoder *encoder,
-		   struct intel_connector *connector,
-		   bool irq_received)
+		   struct intel_connector *connector)
 {
 	intel_sdvo_enable_hotplug(encoder);
 
-	return intel_encoder_hotplug(encoder, connector, irq_received);
+	return intel_encoder_hotplug(encoder, connector);
 }
 
 static bool