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-rw-r--r--drivers/thermal/thermal_sys.c188
1 files changed, 186 insertions, 2 deletions
diff --git a/drivers/thermal/thermal_sys.c b/drivers/thermal/thermal_sys.c
index bd139adc6d32..6378741882f3 100644
--- a/drivers/thermal/thermal_sys.c
+++ b/drivers/thermal/thermal_sys.c
@@ -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);
generated by cgit v1.2.3 (git 2.0.4) at 2024-11-08 22:09:14 +0000