2 files changed, 81 insertions, 29 deletions

diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c
index 07cb2172bd09..bd66bd28a43f 100644
--- a/drivers/acpi/thermal.c
+++ b/drivers/acpi/thermal.c
@@ -716,9 +716,11 @@ static int thermal_get_trend(struct thermal_zone_device *thermal,
         if (thermal_get_trip_type(thermal, trip, &type))
                 return -EINVAL;
 
-        /* Only PASSIVE trip points need TREND */
-        if (type != THERMAL_TRIP_PASSIVE)
-                return -EINVAL;
+        if (type == THERMAL_TRIP_ACTIVE) {
+                /* aggressive active cooling */
+                *trend = THERMAL_TREND_RAISING;
+                return 0;
+        }
 
         /*
          * tz->temperature has already been updated by generic thermal layer,
diff --git a/drivers/thermal/thermal_sys.c b/drivers/thermal/thermal_sys.c
index 0cf3dce55462..735e6e6daada 100644
--- a/drivers/thermal/thermal_sys.c
+++ b/drivers/thermal/thermal_sys.c
@@ -1076,6 +1076,81 @@ void thermal_cooling_device_unregister(struct
 }
 EXPORT_SYMBOL(thermal_cooling_device_unregister);
 
+/*
+ * Cooling algorithm for active trip points
+ *
+ * 1. if the temperature is higher than a trip point,
+ *    a. if the trend is THERMAL_TREND_RAISING, use higher cooling
+ *       state for this trip point
+ *    b. if the trend is THERMAL_TREND_DROPPING, use lower cooling
+ *       state for this trip point
+ *
+ * 2. if the temperature is lower than a trip point, use lower
+ *    cooling state for this trip point
+ *
+ * Note that this behaves the same as the previous passive cooling
+ * algorithm.
+ */
+
+static void thermal_zone_trip_update(struct thermal_zone_device *tz,
+                                     int trip, long temp)
+{
+        struct thermal_cooling_device_instance *instance;
+        struct thermal_cooling_device *cdev = NULL;
+        unsigned long cur_state, max_state;
+        long trip_temp;
+        enum thermal_trend trend;
+
+        tz->ops->get_trip_temp(tz, trip, &trip_temp);
+
+        if (!tz->ops->get_trend || tz->ops->get_trend(tz, trip, &trend)) {
+                /*
+                 * compare the current temperature and previous temperature
+                 * to get the thermal trend, if no special requirement
+                 */
+                if (tz->temperature > tz->last_temperature)
+                        trend = THERMAL_TREND_RAISING;
+                else if (tz->temperature < tz->last_temperature)
+                        trend = THERMAL_TREND_DROPPING;
+                else
+                        trend = THERMAL_TREND_STABLE;
+        }
+
+        if (temp >= trip_temp) {
+                list_for_each_entry(instance, &tz->cooling_devices, node) {
+                        if (instance->trip != trip)
+                                continue;
+
+                        cdev = instance->cdev;
+
+                        cdev->ops->get_cur_state(cdev, &cur_state);
+                        cdev->ops->get_max_state(cdev, &max_state);
+
+                        if (trend == THERMAL_TREND_RAISING) {
+                                cur_state = cur_state < instance->upper ?
+                                            (cur_state + 1) : instance->upper;
+                        } else if (trend == THERMAL_TREND_DROPPING) {
+                                cur_state = cur_state > instance->lower ?
+                                    (cur_state - 1) : instance->lower;
+                        }
+                        cdev->ops->set_cur_state(cdev, cur_state);
+                }
+        } else {        /* below trip */
+                list_for_each_entry(instance, &tz->cooling_devices, node) {
+                        if (instance->trip != trip)
+                                continue;
+
+                        cdev = instance->cdev;
+                        cdev->ops->get_cur_state(cdev, &cur_state);
+
+                        cur_state = cur_state > instance->lower ?
+                                    (cur_state - 1) : instance->lower;
+                        cdev->ops->set_cur_state(cdev, cur_state);
+                }
+        }
+
+        return;
+}
 /**
  * thermal_zone_device_update - force an update of a thermal zone's state
  * @ttz:        the thermal zone to update
@@ -1086,9 +1161,6 @@ void thermal_zone_device_update(struct thermal_zone_device *tz)
         int count, ret = 0;
         long temp, trip_temp;
         enum thermal_trip_type trip_type;
-        struct thermal_cooling_device_instance *instance;
-        struct thermal_cooling_device *cdev;
-        unsigned long cur_state, max_state;
 
         mutex_lock(&tz->lock);
 
@@ -1124,29 +1196,7 @@ void thermal_zone_device_update(struct thermal_zone_device *tz)
                                         tz->ops->notify(tz, count, trip_type);
                         break;
                 case THERMAL_TRIP_ACTIVE:
-                        list_for_each_entry(instance, &tz->cooling_devices,
-                                            node) {
-                                if (instance->trip != count)
-                                        continue;
-
-                                cdev = instance->cdev;
-
-                                cdev->ops->get_cur_state(cdev, &cur_state);
-                                cdev->ops->get_max_state(cdev, &max_state);
-
-                                if (temp >= trip_temp)
-                                        cur_state =
-                                                cur_state < instance->upper ?
-                                                (cur_state + 1) :
-                                                instance->upper;
-                                else
-                                        cur_state =
-                                                cur_state > instance->lower ?
-                                                (cur_state - 1) :
-                                                instance->lower;
-
-                                cdev->ops->set_cur_state(cdev, cur_state);
-                        }
+                        thermal_zone_trip_update(tz, count, temp);
                         break;
                 case THERMAL_TRIP_PASSIVE:
                         if (temp >= trip_temp || tz->passive)