MODULE_DESCRIPTION("Generic thermal management sysfs support");
MODULE_LICENSE("GPL");
-struct thermal_cooling_device_instance {
+#define THERMAL_NO_TARGET -1UL
+/*
+ * This structure is used to describe the behavior of
+ * a certain cooling device on a certain trip point
+ * in a certain thermal zone
+ */
+struct thermal_instance {
int id;
char name[THERMAL_NAME_LENGTH];
struct thermal_zone_device *tz;
struct thermal_cooling_device *cdev;
int trip;
+ unsigned long upper; /* Highest cooling state for this trip point */
+ unsigned long lower; /* Lowest cooling state for this trip point */
+ unsigned long target; /* expected cooling state */
char attr_name[THERMAL_NAME_LENGTH];
struct device_attribute attr;
- struct list_head node;
+ struct list_head tz_node; /* node in tz->thermal_instances */
+ struct list_head cdev_node; /* node in cdev->thermal_instances */
};
static DEFINE_IDR(thermal_tz_idr);
if (!strncmp("Processor", cdev->type,
sizeof("Processor")))
thermal_zone_bind_cooling_device(tz,
- THERMAL_TRIPS_NONE,
- cdev);
+ THERMAL_TRIPS_NONE, cdev,
+ THERMAL_NO_LIMIT,
+ THERMAL_NO_LIMIT);
}
mutex_unlock(&thermal_list_lock);
if (!tz->passive_delay)
tz->passive_delay = 0;
}
- tz->tc1 = 1;
- tz->tc2 = 1;
-
tz->forced_passive = state;
thermal_zone_device_update(tz);
thermal_cooling_device_trip_point_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
- struct thermal_cooling_device_instance *instance;
+ struct thermal_instance *instance;
instance =
- container_of(attr, struct thermal_cooling_device_instance, attr);
+ container_of(attr, struct thermal_instance, attr);
if (instance->trip == THERMAL_TRIPS_NONE)
return sprintf(buf, "-1\n");
temp->tz = tz;
hwmon->count++;
- snprintf(temp->temp_input.name, THERMAL_NAME_LENGTH,
+ snprintf(temp->temp_input.name, sizeof(temp->temp_input.name),
"temp%d_input", hwmon->count);
temp->temp_input.attr.attr.name = temp->temp_input.name;
temp->temp_input.attr.attr.mode = 0444;
if (tz->ops->get_crit_temp) {
unsigned long temperature;
if (!tz->ops->get_crit_temp(tz, &temperature)) {
- snprintf(temp->temp_crit.name, THERMAL_NAME_LENGTH,
+ snprintf(temp->temp_crit.name,
+ sizeof(temp->temp_crit.name),
"temp%d_crit", hwmon->count);
temp->temp_crit.attr.attr.name = temp->temp_crit.name;
temp->temp_crit.attr.attr.mode = 0444;
cancel_delayed_work(&tz->poll_queue);
}
-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
*/
int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
int trip,
- struct thermal_cooling_device *cdev)
+ struct thermal_cooling_device *cdev,
+ unsigned long upper, unsigned long lower)
{
- struct thermal_cooling_device_instance *dev;
- struct thermal_cooling_device_instance *pos;
+ struct thermal_instance *dev;
+ struct thermal_instance *pos;
struct thermal_zone_device *pos1;
struct thermal_cooling_device *pos2;
+ unsigned long max_state;
int result;
if (trip >= tz->trips || (trip < 0 && trip != THERMAL_TRIPS_NONE))
if (tz != pos1 || cdev != pos2)
return -EINVAL;
+ cdev->ops->get_max_state(cdev, &max_state);
+
+ /* lower default 0, upper default max_state */
+ lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
+ upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
+
+ if (lower > upper || upper > max_state)
+ return -EINVAL;
+
dev =
- kzalloc(sizeof(struct thermal_cooling_device_instance), GFP_KERNEL);
+ kzalloc(sizeof(struct thermal_instance), GFP_KERNEL);
if (!dev)
return -ENOMEM;
dev->tz = tz;
dev->cdev = cdev;
dev->trip = trip;
+ dev->upper = upper;
+ dev->lower = lower;
+ dev->target = THERMAL_NO_TARGET;
+
result = get_idr(&tz->idr, &tz->lock, &dev->id);
if (result)
goto free_mem;
goto remove_symbol_link;
mutex_lock(&tz->lock);
- list_for_each_entry(pos, &tz->cooling_devices, node)
+ mutex_lock(&cdev->lock);
+ list_for_each_entry(pos, &tz->thermal_instances, tz_node)
if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
result = -EEXIST;
break;
}
- if (!result)
- list_add_tail(&dev->node, &tz->cooling_devices);
+ if (!result) {
+ list_add_tail(&dev->tz_node, &tz->thermal_instances);
+ list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
+ }
+ mutex_unlock(&cdev->lock);
mutex_unlock(&tz->lock);
if (!result)
int trip,
struct thermal_cooling_device *cdev)
{
- struct thermal_cooling_device_instance *pos, *next;
+ struct thermal_instance *pos, *next;
mutex_lock(&tz->lock);
- list_for_each_entry_safe(pos, next, &tz->cooling_devices, node) {
+ mutex_lock(&cdev->lock);
+ list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
- list_del(&pos->node);
+ list_del(&pos->tz_node);
+ list_del(&pos->cdev_node);
+ mutex_unlock(&cdev->lock);
mutex_unlock(&tz->lock);
goto unbind;
}
}
+ mutex_unlock(&cdev->lock);
mutex_unlock(&tz->lock);
return -ENODEV;
struct thermal_zone_device *pos;
int result;
- if (strlen(type) >= THERMAL_NAME_LENGTH)
+ if (type && strlen(type) >= THERMAL_NAME_LENGTH)
return ERR_PTR(-EINVAL);
if (!ops || !ops->get_max_state || !ops->get_cur_state ||
return ERR_PTR(result);
}
- strcpy(cdev->type, type);
+ strcpy(cdev->type, type ? : "");
+ mutex_init(&cdev->lock);
+ INIT_LIST_HEAD(&cdev->thermal_instances);
cdev->ops = ops;
+ cdev->updated = true;
cdev->device.class = &thermal_class;
cdev->devdata = devdata;
dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
}
EXPORT_SYMBOL(thermal_cooling_device_unregister);
+static void thermal_cdev_do_update(struct thermal_cooling_device *cdev)
+{
+ struct thermal_instance *instance;
+ unsigned long target = 0;
+
+ /* cooling device is updated*/
+ if (cdev->updated)
+ return;
+
+ mutex_lock(&cdev->lock);
+ /* Make sure cdev enters the deepest cooling state */
+ list_for_each_entry(instance, &cdev->thermal_instances, cdev_node) {
+ if (instance->target == THERMAL_NO_TARGET)
+ continue;
+ if (instance->target > target)
+ target = instance->target;
+ }
+ mutex_unlock(&cdev->lock);
+ cdev->ops->set_cur_state(cdev, target);
+ cdev->updated = true;
+}
+
+static void thermal_zone_do_update(struct thermal_zone_device *tz)
+{
+ struct thermal_instance *instance;
+
+ list_for_each_entry(instance, &tz->thermal_instances, tz_node)
+ thermal_cdev_do_update(instance->cdev);
+}
+
+/*
+ * Cooling algorithm for both active and passive cooling
+ *
+ * 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_instance *instance;
+ struct thermal_cooling_device *cdev = NULL;
+ unsigned long cur_state, max_state;
+ long trip_temp;
+ enum thermal_trip_type trip_type;
+ enum thermal_trend trend;
+
+ if (trip == THERMAL_TRIPS_NONE) {
+ trip_temp = tz->forced_passive;
+ trip_type = THERMAL_TRIPS_NONE;
+ } else {
+ tz->ops->get_trip_temp(tz, trip, &trip_temp);
+ tz->ops->get_trip_type(tz, trip, &trip_type);
+ }
+
+ 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->thermal_instances, tz_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;
+ }
+
+ /* activate a passive thermal instance */
+ if ((trip_type == THERMAL_TRIP_PASSIVE ||
+ trip_type == THERMAL_TRIPS_NONE) &&
+ instance->target == THERMAL_NO_TARGET)
+ tz->passive++;
+
+ instance->target = cur_state;
+ cdev->updated = false; /* cooling device needs update */
+ }
+ } else { /* below trip */
+ list_for_each_entry(instance, &tz->thermal_instances, tz_node) {
+ if (instance->trip != trip)
+ continue;
+
+ /* Do not use the inactive thermal instance */
+ if (instance->target == THERMAL_NO_TARGET)
+ continue;
+ cdev = instance->cdev;
+ cdev->ops->get_cur_state(cdev, &cur_state);
+
+ cur_state = cur_state > instance->lower ?
+ (cur_state - 1) : THERMAL_NO_TARGET;
+
+ /* deactivate a passive thermal instance */
+ if ((trip_type == THERMAL_TRIP_PASSIVE ||
+ trip_type == THERMAL_TRIPS_NONE) &&
+ cur_state == THERMAL_NO_TARGET)
+ tz->passive--;
+ instance->target = cur_state;
+ cdev->updated = false; /* cooling device needs update */
+ }
+ }
+
+ return;
+}
/**
* thermal_zone_device_update - force an update of a thermal zone's state
* @ttz: the thermal zone to update
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);
goto leave;
}
+ tz->last_temperature = tz->temperature;
+ tz->temperature = 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);
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);
- }
+ thermal_zone_trip_update(tz, count, temp);
break;
case THERMAL_TRIP_PASSIVE:
if (temp >= trip_temp || tz->passive)
- thermal_zone_device_passive(tz, temp,
- trip_temp, count);
+ thermal_zone_trip_update(tz, count, temp);
break;
}
}
if (tz->forced_passive)
- thermal_zone_device_passive(tz, temp, tz->forced_passive,
- THERMAL_TRIPS_NONE);
-
- tz->last_temperature = temp;
+ thermal_zone_trip_update(tz, THERMAL_TRIPS_NONE, temp);
+ thermal_zone_do_update(tz);
leave:
if (tz->passive)
* @mask: a bit string indicating the writeablility of trip points
* @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
* driven systems)
*
* thermal_zone_device_unregister() must be called when the device is no
- * longer needed. The passive cooling formula uses tc1 and tc2 as described in
- * section 11.1.5.1 of the ACPI specification 3.0.
+ * longer needed. The passive cooling depends on the .get_trend() return value.
*/
struct thermal_zone_device *thermal_zone_device_register(const char *type,
int trips, int mask, void *devdata,
const struct thermal_zone_device_ops *ops,
- int tc1, int tc2, int passive_delay, int polling_delay)
+ int passive_delay, int polling_delay)
{
struct thermal_zone_device *tz;
struct thermal_cooling_device *pos;
int count;
int passive = 0;
- if (strlen(type) >= THERMAL_NAME_LENGTH)
+ if (type && strlen(type) >= THERMAL_NAME_LENGTH)
return ERR_PTR(-EINVAL);
if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips)
if (!tz)
return ERR_PTR(-ENOMEM);
- INIT_LIST_HEAD(&tz->cooling_devices);
+ INIT_LIST_HEAD(&tz->thermal_instances);
idr_init(&tz->idr);
mutex_init(&tz->lock);
result = get_idr(&thermal_tz_idr, &thermal_idr_lock, &tz->id);
return ERR_PTR(result);
}
- strcpy(tz->type, type);
+ strcpy(tz->type, type ? : "");
tz->ops = ops;
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;
projects / karo-tx-linux.git / blobdiff