ACPI: move thermal trip handling to generic thermal layer
[linux-2.6.git] / drivers / thermal / thermal_sys.c
index bd139ad..6378741 100644 (file)
@@ -30,6 +30,7 @@
 #include <linux/idr.h>
 #include <linux/thermal.h>
 #include <linux/spinlock.h>
+#include <linux/reboot.h>
 
 MODULE_AUTHOR("Zhang Rui");
 MODULE_DESCRIPTION("Generic thermal management sysfs support");
@@ -517,6 +518,97 @@ thermal_remove_hwmon_sysfs(struct thermal_zone_device *tz)
 }
 #endif
 
+static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
+                                           int delay)
+{
+       cancel_delayed_work(&(tz->poll_queue));
+
+       if (!delay)
+               return;
+
+       if (delay > 1000)
+               schedule_delayed_work(&(tz->poll_queue),
+                                     round_jiffies(msecs_to_jiffies(delay)));
+       else
+               schedule_delayed_work(&(tz->poll_queue),
+                                     msecs_to_jiffies(delay));
+}
+
+static void thermal_zone_device_passive(struct thermal_zone_device *tz,
+                                       int temp, int trip_temp, int trip)
+{
+       int trend = 0;
+       struct thermal_cooling_device_instance *instance;
+       struct thermal_cooling_device *cdev;
+       long state, max_state;
+
+       /*
+        * Above Trip?
+        * -----------
+        * Calculate the thermal trend (using the passive cooling equation)
+        * and modify the performance limit for all passive cooling devices
+        * accordingly.  Note that we assume symmetry.
+        */
+       if (temp >= trip_temp) {
+               tz->passive = true;
+
+               trend = (tz->tc1 * (temp - tz->last_temperature)) +
+                       (tz->tc2 * (temp - trip_temp));
+
+               /* Heating up? */
+               if (trend > 0) {
+                       list_for_each_entry(instance, &tz->cooling_devices,
+                                           node) {
+                               if (instance->trip != trip)
+                                       continue;
+                               cdev = instance->cdev;
+                               cdev->ops->get_cur_state(cdev, &state);
+                               cdev->ops->get_max_state(cdev, &max_state);
+                               if (state++ < max_state)
+                                       cdev->ops->set_cur_state(cdev, state);
+                       }
+               } else if (trend < 0) { /* Cooling off? */
+                       list_for_each_entry(instance, &tz->cooling_devices,
+                                           node) {
+                               if (instance->trip != trip)
+                                       continue;
+                               cdev = instance->cdev;
+                               cdev->ops->get_cur_state(cdev, &state);
+                               cdev->ops->get_max_state(cdev, &max_state);
+                               if (state > 0)
+                                       cdev->ops->set_cur_state(cdev, --state);
+                       }
+               }
+               return;
+       }
+
+       /*
+        * Below Trip?
+        * -----------
+        * Implement passive cooling hysteresis to slowly increase performance
+        * and avoid thrashing around the passive trip point.  Note that we
+        * assume symmetry.
+        */
+       list_for_each_entry(instance, &tz->cooling_devices, node) {
+               if (instance->trip != trip)
+                       continue;
+               cdev = instance->cdev;
+               cdev->ops->get_cur_state(cdev, &state);
+               cdev->ops->get_max_state(cdev, &max_state);
+               if (state > 0)
+                       cdev->ops->set_cur_state(cdev, --state);
+               if (state == 0)
+                       tz->passive = false;
+       }
+}
+
+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_zone_bind_cooling_device - bind a cooling device to a thermal zone
@@ -787,20 +879,101 @@ void thermal_cooling_device_unregister(struct
 EXPORT_SYMBOL(thermal_cooling_device_unregister);
 
 /**
+ * thermal_zone_device_update - force an update of a thermal zone's state
+ * @ttz:       the thermal zone to update
+ */
+
+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;
+
+       mutex_lock(&tz->lock);
+
+       tz->ops->get_temp(tz, &temp);
+
+       for (count = 0; count < tz->trips; count++) {
+               tz->ops->get_trip_type(tz, count, &trip_type);
+               tz->ops->get_trip_temp(tz, count, &trip_temp);
+
+               switch (trip_type) {
+               case THERMAL_TRIP_CRITICAL:
+                       if (temp > trip_temp) {
+                               if (tz->ops->notify)
+                                       ret = tz->ops->notify(tz, count,
+                                                             trip_type);
+                               if (!ret) {
+                                       printk(KERN_EMERG
+                                              "Critical temperature reached (%ld C), shutting down.\n",
+                                              temp/1000);
+                                       orderly_poweroff(true);
+                               }
+                       }
+                       break;
+               case THERMAL_TRIP_HOT:
+                       if (temp > trip_temp)
+                               if (tz->ops->notify)
+                                       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;
+
+                               if (temp > trip_temp)
+                                       cdev->ops->set_cur_state(cdev, 1);
+                               else
+                                       cdev->ops->set_cur_state(cdev, 0);
+                       }
+                       break;
+               case THERMAL_TRIP_PASSIVE:
+                       if (temp > trip_temp || tz->passive)
+                               thermal_zone_device_passive(tz, temp,
+                                                           trip_temp, count);
+                       break;
+               }
+       }
+       tz->last_temperature = temp;
+       if (tz->passive)
+               thermal_zone_device_set_polling(tz, tz->passive_delay);
+       else if (tz->polling_delay)
+               thermal_zone_device_set_polling(tz, tz->polling_delay);
+       mutex_unlock(&tz->lock);
+}
+EXPORT_SYMBOL(thermal_zone_device_update);
+
+/**
  * thermal_zone_device_register - register a new thermal zone device
  * @type:      the thermal zone device type
  * @trips:     the number of trip points the thermal zone support
  * @devdata:   private device data
  * @ops:       standard thermal zone device callbacks
+ * @tc1:       thermal coefficient 1 for passive calculations
+ * @tc2:       thermal coefficient 2 for passive calculations
+ * @passive_delay: number of milliseconds to wait between polls when
+ *                performing passive cooling
+ * @polling_delay: number of milliseconds to wait between polls when checking
+ *                whether trip points have been crossed (0 for interrupt
+ *                driven systems)
  *
  * thermal_zone_device_unregister() must be called when the device is no
- * longer needed.
+ * longer needed. The passive cooling formula uses tc1 and tc2 as described in
+ * section 11.1.5.1 of the ACPI specification 3.0.
  */
 struct thermal_zone_device *thermal_zone_device_register(char *type,
                                                         int trips,
                                                         void *devdata, struct
                                                         thermal_zone_device_ops
-                                                        *ops)
+                                                        *ops, int tc1, int
+                                                        tc2,
+                                                        int passive_delay,
+                                                        int polling_delay)
 {
        struct thermal_zone_device *tz;
        struct thermal_cooling_device *pos;
@@ -834,6 +1007,11 @@ struct thermal_zone_device *thermal_zone_device_register(char *type,
        tz->device.class = &thermal_class;
        tz->devdata = devdata;
        tz->trips = trips;
+       tz->tc1 = tc1;
+       tz->tc2 = tc2;
+       tz->passive_delay = passive_delay;
+       tz->polling_delay = polling_delay;
+
        dev_set_name(&tz->device, "thermal_zone%d", tz->id);
        result = device_register(&tz->device);
        if (result) {
@@ -879,6 +1057,10 @@ struct thermal_zone_device *thermal_zone_device_register(char *type,
                }
        mutex_unlock(&thermal_list_lock);
 
+       INIT_DELAYED_WORK(&(tz->poll_queue), thermal_zone_device_check);
+
+       thermal_zone_device_update(tz);
+
        if (!result)
                return tz;
 
@@ -918,6 +1100,8 @@ void thermal_zone_device_unregister(struct thermal_zone_device *tz)
                    tz->ops->unbind(tz, cdev);
        mutex_unlock(&thermal_list_lock);
 
+       thermal_zone_device_set_polling(tz, 0);
+
        if (tz->type[0])
                device_remove_file(&tz->device, &dev_attr_type);
        device_remove_file(&tz->device, &dev_attr_temp);