thermal: core: Fix issues related to thermal zone resume

Index: linux-pm/drivers/thermal/thermal_core.c
===================================================================
@@ -37,8 +37,6 @@ static LIST_HEAD(thermal_governor_list);
 static DEFINE_MUTEX(thermal_list_lock);
 static DEFINE_MUTEX(thermal_governor_lock);
 
-static atomic_t in_suspend;
-
 static struct thermal_governor *def_governor;
 
 /*

@@ -427,7 +425,7 @@ void __thermal_zone_device_update(struct
 {
 	struct thermal_trip *trip;
 
-	if (atomic_read(&in_suspend))
+	if (tz->suspended)
 		return;
 
 	if (!thermal_zone_device_is_enabled(tz))

@@ -1538,17 +1536,35 @@ static int thermal_pm_notify(struct noti
 	case PM_HIBERNATION_PREPARE:
 	case PM_RESTORE_PREPARE:
 	case PM_SUSPEND_PREPARE:
-		atomic_set(&in_suspend, 1);
+		mutex_lock(&thermal_list_lock);
+
+		list_for_each_entry(tz, &thermal_tz_list, node) {
+			mutex_lock(&tz->lock);
+
+			tz->suspended = true;
+
+			mutex_unlock(&tz->lock);
+		}
+
+		mutex_unlock(&thermal_list_lock);
 		break;
 	case PM_POST_HIBERNATION:
 	case PM_POST_RESTORE:
 	case PM_POST_SUSPEND:
-		atomic_set(&in_suspend, 0);
+		mutex_lock(&thermal_list_lock);
+
 		list_for_each_entry(tz, &thermal_tz_list, node) {
+			mutex_lock(&tz->lock);
+
+			tz->suspended = false;
+
 			thermal_zone_device_init(tz);
-			thermal_zone_device_update(tz,
-						   THERMAL_EVENT_UNSPECIFIED);
+			__thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
+
+			mutex_unlock(&tz->lock);
 		}
+
+		mutex_unlock(&thermal_list_lock);
 		break;
 	default:
 		break;

Index: linux-pm/include/linux/thermal.h
===================================================================
@@ -152,6 +152,7 @@ struct thermal_cooling_device {
  * @node:	node in thermal_tz_list (in thermal_core.c)
  * @poll_queue:	delayed work for polling
  * @notify_event: Last notification event
+ * @suspended: thermal zone suspend indicator
  */
 struct thermal_zone_device {
 	int id;

@@ -185,6 +186,7 @@ struct thermal_zone_device {
 	struct list_head node;
 	struct delayed_work poll_queue;
 	enum thermal_notify_event notify_event;
+	bool suspended;
 };
 
 /**

Index: linux-pm/drivers/thermal/thermal_core.c
===================================================================
@@ -410,9 +410,20 @@ static void update_temperature(struct th
 	thermal_genl_sampling_temp(tz->id, temp);
 }
 
+static void thermal_zone_device_check(struct work_struct *work)
+{
+	struct thermal_zone_device *tz = container_of(work, struct
+						      thermal_zone_device,
+						      poll_queue.work);
+	thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
+}
+
 static void thermal_zone_device_init(struct thermal_zone_device *tz)
 {
 	struct thermal_instance *pos;
+
+	INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
+
 	tz->temperature = THERMAL_TEMP_INVALID;
 	tz->prev_low_trip = -INT_MAX;
 	tz->prev_high_trip = INT_MAX;

@@ -509,14 +520,6 @@ void thermal_zone_device_update(struct t
 }
 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
 
-static void thermal_zone_device_check(struct work_struct *work)
-{
-	struct thermal_zone_device *tz = container_of(work, struct
-						      thermal_zone_device,
-						      poll_queue.work);
-	thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
-}
-
 int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
 			      void *data)
 {

@@ -1372,8 +1375,6 @@ thermal_zone_device_register_with_trips(
 	/* Bind cooling devices for this zone */
 	bind_tz(tz);
 
-	INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
-
 	thermal_zone_device_init(tz);
 	/* Update the new thermal zone and mark it as already updated. */
 	if (atomic_cmpxchg(&tz->need_update, 1, 0))

@@ -1556,6 +1557,8 @@ static int thermal_pm_notify(struct noti
 		list_for_each_entry(tz, &thermal_tz_list, node) {
 			mutex_lock(&tz->lock);
 
+			cancel_delayed_work(&tz->poll_queue);
+
 			tz->suspended = false;
 
 			thermal_zone_device_init(tz);

Index: linux-pm/drivers/thermal/thermal_core.c
===================================================================
@@ -1528,6 +1528,22 @@ exit:
 }
 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
 
+static void thermal_zone_device_resume(struct work_struct *work)
+{
+	struct thermal_zone_device *tz;
+
+	tz = container_of(work, struct thermal_zone_device, poll_queue.work);
+
+	mutex_lock(&tz->lock);
+
+	tz->suspended = false;
+
+	thermal_zone_device_init(tz);
+	__thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
+
+	mutex_unlock(&tz->lock);
+}
+
 static int thermal_pm_notify(struct notifier_block *nb,
 			     unsigned long mode, void *_unused)
 {

@@ -1559,10 +1575,16 @@ static int thermal_pm_notify(struct noti
 
 			cancel_delayed_work(&tz->poll_queue);
 
-			tz->suspended = false;
-
-			thermal_zone_device_init(tz);
-			__thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
+			/*
+			 * Replace the work function with the resume one, which
+			 * will restore the original work function and schedule
+			 * the polling work if needed.
+			 */
+			INIT_DELAYED_WORK(&tz->poll_queue,
+					  thermal_zone_device_resume);
+			/* Queue up the work without a delay. */
+			mod_delayed_work(system_freezable_power_efficient_wq,
+					 &tz->poll_queue, 0);
 
 			mutex_unlock(&tz->lock);
 		}