linux/drivers/thermal/thermal_sys.c
Matthew Garrett 03a971a289 thermal: support forcing support for passive cooling
Due to poor thermal design or Linux driving hardware outside its thermal
envelope, some systems will reach critical temperature and shut down
under high load. This patch adds support for forcing a polling-based
passive trip point if the firmware doesn't provide one. The assumption
is made that the processor is the most practical means to reduce the
dynamic heat generation, so hitting the passive thermal limit will cause
the CPU to be throttled until the temperature stabalises around the
defined value.

UI is provided via a "passive" sysfs entry in the thermal zone
directory. It accepts a decimal value in millidegrees celsius, or "0" to
disable the functionality. Default behaviour is for this functionality
to be disabled.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-03-27 16:58:22 -04:00

1225 lines
31 KiB
C

/*
* thermal.c - Generic Thermal Management Sysfs support.
*
* Copyright (C) 2008 Intel Corp
* Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
* Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
#include <linux/module.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/kdev_t.h>
#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");
MODULE_LICENSE("GPL");
#define PREFIX "Thermal: "
struct thermal_cooling_device_instance {
int id;
char name[THERMAL_NAME_LENGTH];
struct thermal_zone_device *tz;
struct thermal_cooling_device *cdev;
int trip;
char attr_name[THERMAL_NAME_LENGTH];
struct device_attribute attr;
struct list_head node;
};
static DEFINE_IDR(thermal_tz_idr);
static DEFINE_IDR(thermal_cdev_idr);
static DEFINE_MUTEX(thermal_idr_lock);
static LIST_HEAD(thermal_tz_list);
static LIST_HEAD(thermal_cdev_list);
static DEFINE_MUTEX(thermal_list_lock);
static int get_idr(struct idr *idr, struct mutex *lock, int *id)
{
int err;
again:
if (unlikely(idr_pre_get(idr, GFP_KERNEL) == 0))
return -ENOMEM;
if (lock)
mutex_lock(lock);
err = idr_get_new(idr, NULL, id);
if (lock)
mutex_unlock(lock);
if (unlikely(err == -EAGAIN))
goto again;
else if (unlikely(err))
return err;
*id = *id & MAX_ID_MASK;
return 0;
}
static void release_idr(struct idr *idr, struct mutex *lock, int id)
{
if (lock)
mutex_lock(lock);
idr_remove(idr, id);
if (lock)
mutex_unlock(lock);
}
/* sys I/F for thermal zone */
#define to_thermal_zone(_dev) \
container_of(_dev, struct thermal_zone_device, device)
static ssize_t
type_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct thermal_zone_device *tz = to_thermal_zone(dev);
return sprintf(buf, "%s\n", tz->type);
}
static ssize_t
temp_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct thermal_zone_device *tz = to_thermal_zone(dev);
long temperature;
int ret;
if (!tz->ops->get_temp)
return -EPERM;
ret = tz->ops->get_temp(tz, &temperature);
if (ret)
return ret;
return sprintf(buf, "%ld\n", temperature);
}
static ssize_t
mode_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct thermal_zone_device *tz = to_thermal_zone(dev);
enum thermal_device_mode mode;
int result;
if (!tz->ops->get_mode)
return -EPERM;
result = tz->ops->get_mode(tz, &mode);
if (result)
return result;
return sprintf(buf, "%s\n", mode == THERMAL_DEVICE_ENABLED ? "enabled"
: "disabled");
}
static ssize_t
mode_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct thermal_zone_device *tz = to_thermal_zone(dev);
int result;
if (!tz->ops->set_mode)
return -EPERM;
if (!strncmp(buf, "enabled", sizeof("enabled")))
result = tz->ops->set_mode(tz, THERMAL_DEVICE_ENABLED);
else if (!strncmp(buf, "disabled", sizeof("disabled")))
result = tz->ops->set_mode(tz, THERMAL_DEVICE_DISABLED);
else
result = -EINVAL;
if (result)
return result;
return count;
}
static ssize_t
trip_point_type_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct thermal_zone_device *tz = to_thermal_zone(dev);
enum thermal_trip_type type;
int trip, result;
if (!tz->ops->get_trip_type)
return -EPERM;
if (!sscanf(attr->attr.name, "trip_point_%d_type", &trip))
return -EINVAL;
result = tz->ops->get_trip_type(tz, trip, &type);
if (result)
return result;
switch (type) {
case THERMAL_TRIP_CRITICAL:
return sprintf(buf, "critical");
case THERMAL_TRIP_HOT:
return sprintf(buf, "hot");
case THERMAL_TRIP_PASSIVE:
return sprintf(buf, "passive");
case THERMAL_TRIP_ACTIVE:
return sprintf(buf, "active");
default:
return sprintf(buf, "unknown");
}
}
static ssize_t
trip_point_temp_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct thermal_zone_device *tz = to_thermal_zone(dev);
int trip, ret;
long temperature;
if (!tz->ops->get_trip_temp)
return -EPERM;
if (!sscanf(attr->attr.name, "trip_point_%d_temp", &trip))
return -EINVAL;
ret = tz->ops->get_trip_temp(tz, trip, &temperature);
if (ret)
return ret;
return sprintf(buf, "%ld\n", temperature);
}
static ssize_t
passive_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct thermal_zone_device *tz = to_thermal_zone(dev);
struct thermal_cooling_device *cdev = NULL;
int state;
if (!sscanf(buf, "%d\n", &state))
return -EINVAL;
if (state && !tz->forced_passive) {
mutex_lock(&thermal_list_lock);
list_for_each_entry(cdev, &thermal_cdev_list, node) {
if (!strncmp("Processor", cdev->type,
sizeof("Processor")))
thermal_zone_bind_cooling_device(tz,
THERMAL_TRIPS_NONE,
cdev);
}
mutex_unlock(&thermal_list_lock);
} else if (!state && tz->forced_passive) {
mutex_lock(&thermal_list_lock);
list_for_each_entry(cdev, &thermal_cdev_list, node) {
if (!strncmp("Processor", cdev->type,
sizeof("Processor")))
thermal_zone_unbind_cooling_device(tz,
THERMAL_TRIPS_NONE,
cdev);
}
mutex_unlock(&thermal_list_lock);
}
tz->tc1 = 1;
tz->tc2 = 1;
if (!tz->passive_delay)
tz->passive_delay = 1000;
if (!tz->polling_delay)
tz->polling_delay = 10000;
tz->forced_passive = state;
thermal_zone_device_update(tz);
return count;
}
static ssize_t
passive_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct thermal_zone_device *tz = to_thermal_zone(dev);
return sprintf(buf, "%d\n", tz->forced_passive);
}
static DEVICE_ATTR(type, 0444, type_show, NULL);
static DEVICE_ATTR(temp, 0444, temp_show, NULL);
static DEVICE_ATTR(mode, 0644, mode_show, mode_store);
static DEVICE_ATTR(passive, S_IRUGO | S_IWUSR, passive_show, \
passive_store);
static struct device_attribute trip_point_attrs[] = {
__ATTR(trip_point_0_type, 0444, trip_point_type_show, NULL),
__ATTR(trip_point_0_temp, 0444, trip_point_temp_show, NULL),
__ATTR(trip_point_1_type, 0444, trip_point_type_show, NULL),
__ATTR(trip_point_1_temp, 0444, trip_point_temp_show, NULL),
__ATTR(trip_point_2_type, 0444, trip_point_type_show, NULL),
__ATTR(trip_point_2_temp, 0444, trip_point_temp_show, NULL),
__ATTR(trip_point_3_type, 0444, trip_point_type_show, NULL),
__ATTR(trip_point_3_temp, 0444, trip_point_temp_show, NULL),
__ATTR(trip_point_4_type, 0444, trip_point_type_show, NULL),
__ATTR(trip_point_4_temp, 0444, trip_point_temp_show, NULL),
__ATTR(trip_point_5_type, 0444, trip_point_type_show, NULL),
__ATTR(trip_point_5_temp, 0444, trip_point_temp_show, NULL),
__ATTR(trip_point_6_type, 0444, trip_point_type_show, NULL),
__ATTR(trip_point_6_temp, 0444, trip_point_temp_show, NULL),
__ATTR(trip_point_7_type, 0444, trip_point_type_show, NULL),
__ATTR(trip_point_7_temp, 0444, trip_point_temp_show, NULL),
__ATTR(trip_point_8_type, 0444, trip_point_type_show, NULL),
__ATTR(trip_point_8_temp, 0444, trip_point_temp_show, NULL),
__ATTR(trip_point_9_type, 0444, trip_point_type_show, NULL),
__ATTR(trip_point_9_temp, 0444, trip_point_temp_show, NULL),
__ATTR(trip_point_10_type, 0444, trip_point_type_show, NULL),
__ATTR(trip_point_10_temp, 0444, trip_point_temp_show, NULL),
__ATTR(trip_point_11_type, 0444, trip_point_type_show, NULL),
__ATTR(trip_point_11_temp, 0444, trip_point_temp_show, NULL),
};
#define TRIP_POINT_ATTR_ADD(_dev, _index, result) \
do { \
result = device_create_file(_dev, \
&trip_point_attrs[_index * 2]); \
if (result) \
break; \
result = device_create_file(_dev, \
&trip_point_attrs[_index * 2 + 1]); \
} while (0)
#define TRIP_POINT_ATTR_REMOVE(_dev, _index) \
do { \
device_remove_file(_dev, &trip_point_attrs[_index * 2]); \
device_remove_file(_dev, &trip_point_attrs[_index * 2 + 1]); \
} while (0)
/* sys I/F for cooling device */
#define to_cooling_device(_dev) \
container_of(_dev, struct thermal_cooling_device, device)
static ssize_t
thermal_cooling_device_type_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct thermal_cooling_device *cdev = to_cooling_device(dev);
return sprintf(buf, "%s\n", cdev->type);
}
static ssize_t
thermal_cooling_device_max_state_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct thermal_cooling_device *cdev = to_cooling_device(dev);
unsigned long state;
int ret;
ret = cdev->ops->get_max_state(cdev, &state);
if (ret)
return ret;
return sprintf(buf, "%ld\n", state);
}
static ssize_t
thermal_cooling_device_cur_state_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct thermal_cooling_device *cdev = to_cooling_device(dev);
unsigned long state;
int ret;
ret = cdev->ops->get_cur_state(cdev, &state);
if (ret)
return ret;
return sprintf(buf, "%ld\n", state);
}
static ssize_t
thermal_cooling_device_cur_state_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct thermal_cooling_device *cdev = to_cooling_device(dev);
unsigned long state;
int result;
if (!sscanf(buf, "%ld\n", &state))
return -EINVAL;
if (state < 0)
return -EINVAL;
result = cdev->ops->set_cur_state(cdev, state);
if (result)
return result;
return count;
}
static struct device_attribute dev_attr_cdev_type =
__ATTR(type, 0444, thermal_cooling_device_type_show, NULL);
static DEVICE_ATTR(max_state, 0444,
thermal_cooling_device_max_state_show, NULL);
static DEVICE_ATTR(cur_state, 0644,
thermal_cooling_device_cur_state_show,
thermal_cooling_device_cur_state_store);
static ssize_t
thermal_cooling_device_trip_point_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct thermal_cooling_device_instance *instance;
instance =
container_of(attr, struct thermal_cooling_device_instance, attr);
if (instance->trip == THERMAL_TRIPS_NONE)
return sprintf(buf, "-1\n");
else
return sprintf(buf, "%d\n", instance->trip);
}
/* Device management */
#if defined(CONFIG_THERMAL_HWMON)
/* hwmon sys I/F */
#include <linux/hwmon.h>
static LIST_HEAD(thermal_hwmon_list);
static ssize_t
name_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct thermal_hwmon_device *hwmon = dev->driver_data;
return sprintf(buf, "%s\n", hwmon->type);
}
static DEVICE_ATTR(name, 0444, name_show, NULL);
static ssize_t
temp_input_show(struct device *dev, struct device_attribute *attr, char *buf)
{
long temperature;
int ret;
struct thermal_hwmon_attr *hwmon_attr
= container_of(attr, struct thermal_hwmon_attr, attr);
struct thermal_zone_device *tz
= container_of(hwmon_attr, struct thermal_zone_device,
temp_input);
ret = tz->ops->get_temp(tz, &temperature);
if (ret)
return ret;
return sprintf(buf, "%ld\n", temperature);
}
static ssize_t
temp_crit_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct thermal_hwmon_attr *hwmon_attr
= container_of(attr, struct thermal_hwmon_attr, attr);
struct thermal_zone_device *tz
= container_of(hwmon_attr, struct thermal_zone_device,
temp_crit);
long temperature;
int ret;
ret = tz->ops->get_trip_temp(tz, 0, &temperature);
if (ret)
return ret;
return sprintf(buf, "%ld\n", temperature);
}
static int
thermal_add_hwmon_sysfs(struct thermal_zone_device *tz)
{
struct thermal_hwmon_device *hwmon;
int new_hwmon_device = 1;
int result;
mutex_lock(&thermal_list_lock);
list_for_each_entry(hwmon, &thermal_hwmon_list, node)
if (!strcmp(hwmon->type, tz->type)) {
new_hwmon_device = 0;
mutex_unlock(&thermal_list_lock);
goto register_sys_interface;
}
mutex_unlock(&thermal_list_lock);
hwmon = kzalloc(sizeof(struct thermal_hwmon_device), GFP_KERNEL);
if (!hwmon)
return -ENOMEM;
INIT_LIST_HEAD(&hwmon->tz_list);
strlcpy(hwmon->type, tz->type, THERMAL_NAME_LENGTH);
hwmon->device = hwmon_device_register(NULL);
if (IS_ERR(hwmon->device)) {
result = PTR_ERR(hwmon->device);
goto free_mem;
}
hwmon->device->driver_data = hwmon;
result = device_create_file(hwmon->device, &dev_attr_name);
if (result)
goto unregister_hwmon_device;
register_sys_interface:
tz->hwmon = hwmon;
hwmon->count++;
snprintf(tz->temp_input.name, THERMAL_NAME_LENGTH,
"temp%d_input", hwmon->count);
tz->temp_input.attr.attr.name = tz->temp_input.name;
tz->temp_input.attr.attr.mode = 0444;
tz->temp_input.attr.show = temp_input_show;
result = device_create_file(hwmon->device, &tz->temp_input.attr);
if (result)
goto unregister_hwmon_device;
if (tz->ops->get_crit_temp) {
unsigned long temperature;
if (!tz->ops->get_crit_temp(tz, &temperature)) {
snprintf(tz->temp_crit.name, THERMAL_NAME_LENGTH,
"temp%d_crit", hwmon->count);
tz->temp_crit.attr.attr.name = tz->temp_crit.name;
tz->temp_crit.attr.attr.mode = 0444;
tz->temp_crit.attr.show = temp_crit_show;
result = device_create_file(hwmon->device,
&tz->temp_crit.attr);
if (result)
goto unregister_hwmon_device;
}
}
mutex_lock(&thermal_list_lock);
if (new_hwmon_device)
list_add_tail(&hwmon->node, &thermal_hwmon_list);
list_add_tail(&tz->hwmon_node, &hwmon->tz_list);
mutex_unlock(&thermal_list_lock);
return 0;
unregister_hwmon_device:
device_remove_file(hwmon->device, &tz->temp_crit.attr);
device_remove_file(hwmon->device, &tz->temp_input.attr);
if (new_hwmon_device) {
device_remove_file(hwmon->device, &dev_attr_name);
hwmon_device_unregister(hwmon->device);
}
free_mem:
if (new_hwmon_device)
kfree(hwmon);
return result;
}
static void
thermal_remove_hwmon_sysfs(struct thermal_zone_device *tz)
{
struct thermal_hwmon_device *hwmon = tz->hwmon;
tz->hwmon = NULL;
device_remove_file(hwmon->device, &tz->temp_input.attr);
device_remove_file(hwmon->device, &tz->temp_crit.attr);
mutex_lock(&thermal_list_lock);
list_del(&tz->hwmon_node);
if (!list_empty(&hwmon->tz_list)) {
mutex_unlock(&thermal_list_lock);
return;
}
list_del(&hwmon->node);
mutex_unlock(&thermal_list_lock);
device_remove_file(hwmon->device, &dev_attr_name);
hwmon_device_unregister(hwmon->device);
kfree(hwmon);
}
#else
static int
thermal_add_hwmon_sysfs(struct thermal_zone_device *tz)
{
return 0;
}
static void
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
* @tz: thermal zone device
* @trip: indicates which trip point the cooling devices is
* associated with in this thermal zone.
* @cdev: thermal cooling device
*
* This function is usually called in the thermal zone device .bind callback.
*/
int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
int trip,
struct thermal_cooling_device *cdev)
{
struct thermal_cooling_device_instance *dev;
struct thermal_cooling_device_instance *pos;
struct thermal_zone_device *pos1;
struct thermal_cooling_device *pos2;
int result;
if (trip >= tz->trips || (trip < 0 && trip != THERMAL_TRIPS_NONE))
return -EINVAL;
list_for_each_entry(pos1, &thermal_tz_list, node) {
if (pos1 == tz)
break;
}
list_for_each_entry(pos2, &thermal_cdev_list, node) {
if (pos2 == cdev)
break;
}
if (tz != pos1 || cdev != pos2)
return -EINVAL;
dev =
kzalloc(sizeof(struct thermal_cooling_device_instance), GFP_KERNEL);
if (!dev)
return -ENOMEM;
dev->tz = tz;
dev->cdev = cdev;
dev->trip = trip;
result = get_idr(&tz->idr, &tz->lock, &dev->id);
if (result)
goto free_mem;
sprintf(dev->name, "cdev%d", dev->id);
result =
sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
if (result)
goto release_idr;
sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
dev->attr.attr.name = dev->attr_name;
dev->attr.attr.mode = 0444;
dev->attr.show = thermal_cooling_device_trip_point_show;
result = device_create_file(&tz->device, &dev->attr);
if (result)
goto remove_symbol_link;
mutex_lock(&tz->lock);
list_for_each_entry(pos, &tz->cooling_devices, node)
if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
result = -EEXIST;
break;
}
if (!result)
list_add_tail(&dev->node, &tz->cooling_devices);
mutex_unlock(&tz->lock);
if (!result)
return 0;
device_remove_file(&tz->device, &dev->attr);
remove_symbol_link:
sysfs_remove_link(&tz->device.kobj, dev->name);
release_idr:
release_idr(&tz->idr, &tz->lock, dev->id);
free_mem:
kfree(dev);
return result;
}
EXPORT_SYMBOL(thermal_zone_bind_cooling_device);
/**
* thermal_zone_unbind_cooling_device - unbind a cooling device from a thermal zone
* @tz: thermal zone device
* @trip: indicates which trip point the cooling devices is
* associated with in this thermal zone.
* @cdev: thermal cooling device
*
* This function is usually called in the thermal zone device .unbind callback.
*/
int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
int trip,
struct thermal_cooling_device *cdev)
{
struct thermal_cooling_device_instance *pos, *next;
mutex_lock(&tz->lock);
list_for_each_entry_safe(pos, next, &tz->cooling_devices, node) {
if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
list_del(&pos->node);
mutex_unlock(&tz->lock);
goto unbind;
}
}
mutex_unlock(&tz->lock);
return -ENODEV;
unbind:
device_remove_file(&tz->device, &pos->attr);
sysfs_remove_link(&tz->device.kobj, pos->name);
release_idr(&tz->idr, &tz->lock, pos->id);
kfree(pos);
return 0;
}
EXPORT_SYMBOL(thermal_zone_unbind_cooling_device);
static void thermal_release(struct device *dev)
{
struct thermal_zone_device *tz;
struct thermal_cooling_device *cdev;
if (!strncmp(dev_name(dev), "thermal_zone", sizeof "thermal_zone" - 1)) {
tz = to_thermal_zone(dev);
kfree(tz);
} else {
cdev = to_cooling_device(dev);
kfree(cdev);
}
}
static struct class thermal_class = {
.name = "thermal",
.dev_release = thermal_release,
};
/**
* thermal_cooling_device_register - register a new thermal cooling device
* @type: the thermal cooling device type.
* @devdata: device private data.
* @ops: standard thermal cooling devices callbacks.
*/
struct thermal_cooling_device *thermal_cooling_device_register(char *type,
void *devdata,
struct
thermal_cooling_device_ops
*ops)
{
struct thermal_cooling_device *cdev;
struct thermal_zone_device *pos;
int result;
if (strlen(type) >= THERMAL_NAME_LENGTH)
return ERR_PTR(-EINVAL);
if (!ops || !ops->get_max_state || !ops->get_cur_state ||
!ops->set_cur_state)
return ERR_PTR(-EINVAL);
cdev = kzalloc(sizeof(struct thermal_cooling_device), GFP_KERNEL);
if (!cdev)
return ERR_PTR(-ENOMEM);
result = get_idr(&thermal_cdev_idr, &thermal_idr_lock, &cdev->id);
if (result) {
kfree(cdev);
return ERR_PTR(result);
}
strcpy(cdev->type, type);
cdev->ops = ops;
cdev->device.class = &thermal_class;
cdev->devdata = devdata;
dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
result = device_register(&cdev->device);
if (result) {
release_idr(&thermal_cdev_idr, &thermal_idr_lock, cdev->id);
kfree(cdev);
return ERR_PTR(result);
}
/* sys I/F */
if (type) {
result = device_create_file(&cdev->device, &dev_attr_cdev_type);
if (result)
goto unregister;
}
result = device_create_file(&cdev->device, &dev_attr_max_state);
if (result)
goto unregister;
result = device_create_file(&cdev->device, &dev_attr_cur_state);
if (result)
goto unregister;
mutex_lock(&thermal_list_lock);
list_add(&cdev->node, &thermal_cdev_list);
list_for_each_entry(pos, &thermal_tz_list, node) {
if (!pos->ops->bind)
continue;
result = pos->ops->bind(pos, cdev);
if (result)
break;
}
mutex_unlock(&thermal_list_lock);
if (!result)
return cdev;
unregister:
release_idr(&thermal_cdev_idr, &thermal_idr_lock, cdev->id);
device_unregister(&cdev->device);
return ERR_PTR(result);
}
EXPORT_SYMBOL(thermal_cooling_device_register);
/**
* thermal_cooling_device_unregister - removes the registered thermal cooling device
* @cdev: the thermal cooling device to remove.
*
* thermal_cooling_device_unregister() must be called when the device is no
* longer needed.
*/
void thermal_cooling_device_unregister(struct
thermal_cooling_device
*cdev)
{
struct thermal_zone_device *tz;
struct thermal_cooling_device *pos = NULL;
if (!cdev)
return;
mutex_lock(&thermal_list_lock);
list_for_each_entry(pos, &thermal_cdev_list, node)
if (pos == cdev)
break;
if (pos != cdev) {
/* thermal cooling device not found */
mutex_unlock(&thermal_list_lock);
return;
}
list_del(&cdev->node);
list_for_each_entry(tz, &thermal_tz_list, node) {
if (!tz->ops->unbind)
continue;
tz->ops->unbind(tz, cdev);
}
mutex_unlock(&thermal_list_lock);
if (cdev->type[0])
device_remove_file(&cdev->device, &dev_attr_cdev_type);
device_remove_file(&cdev->device, &dev_attr_max_state);
device_remove_file(&cdev->device, &dev_attr_cur_state);
release_idr(&thermal_cdev_idr, &thermal_idr_lock, cdev->id);
device_unregister(&cdev->device);
return;
}
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;
}
}
if (tz->forced_passive)
thermal_zone_device_passive(tz, temp, tz->forced_passive,
THERMAL_TRIPS_NONE);
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. 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, int tc1, int
tc2,
int passive_delay,
int polling_delay)
{
struct thermal_zone_device *tz;
struct thermal_cooling_device *pos;
enum thermal_trip_type trip_type;
int result;
int count;
int passive = 0;
if (strlen(type) >= THERMAL_NAME_LENGTH)
return ERR_PTR(-EINVAL);
if (trips > THERMAL_MAX_TRIPS || trips < 0)
return ERR_PTR(-EINVAL);
if (!ops || !ops->get_temp)
return ERR_PTR(-EINVAL);
tz = kzalloc(sizeof(struct thermal_zone_device), GFP_KERNEL);
if (!tz)
return ERR_PTR(-ENOMEM);
INIT_LIST_HEAD(&tz->cooling_devices);
idr_init(&tz->idr);
mutex_init(&tz->lock);
result = get_idr(&thermal_tz_idr, &thermal_idr_lock, &tz->id);
if (result) {
kfree(tz);
return ERR_PTR(result);
}
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;
dev_set_name(&tz->device, "thermal_zone%d", tz->id);
result = device_register(&tz->device);
if (result) {
release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
kfree(tz);
return ERR_PTR(result);
}
/* sys I/F */
if (type) {
result = device_create_file(&tz->device, &dev_attr_type);
if (result)
goto unregister;
}
result = device_create_file(&tz->device, &dev_attr_temp);
if (result)
goto unregister;
if (ops->get_mode) {
result = device_create_file(&tz->device, &dev_attr_mode);
if (result)
goto unregister;
}
for (count = 0; count < trips; count++) {
TRIP_POINT_ATTR_ADD(&tz->device, count, result);
if (result)
goto unregister;
tz->ops->get_trip_type(tz, count, &trip_type);
if (trip_type == THERMAL_TRIP_PASSIVE)
passive = 1;
}
if (!passive)
result = device_create_file(&tz->device,
&dev_attr_passive);
if (result)
goto unregister;
result = thermal_add_hwmon_sysfs(tz);
if (result)
goto unregister;
mutex_lock(&thermal_list_lock);
list_add_tail(&tz->node, &thermal_tz_list);
if (ops->bind)
list_for_each_entry(pos, &thermal_cdev_list, node) {
result = ops->bind(tz, pos);
if (result)
break;
}
mutex_unlock(&thermal_list_lock);
INIT_DELAYED_WORK(&(tz->poll_queue), thermal_zone_device_check);
thermal_zone_device_update(tz);
if (!result)
return tz;
unregister:
release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
device_unregister(&tz->device);
return ERR_PTR(result);
}
EXPORT_SYMBOL(thermal_zone_device_register);
/**
* thermal_device_unregister - removes the registered thermal zone device
* @tz: the thermal zone device to remove
*/
void thermal_zone_device_unregister(struct thermal_zone_device *tz)
{
struct thermal_cooling_device *cdev;
struct thermal_zone_device *pos = NULL;
int count;
if (!tz)
return;
mutex_lock(&thermal_list_lock);
list_for_each_entry(pos, &thermal_tz_list, node)
if (pos == tz)
break;
if (pos != tz) {
/* thermal zone device not found */
mutex_unlock(&thermal_list_lock);
return;
}
list_del(&tz->node);
if (tz->ops->unbind)
list_for_each_entry(cdev, &thermal_cdev_list, node)
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);
if (tz->ops->get_mode)
device_remove_file(&tz->device, &dev_attr_mode);
for (count = 0; count < tz->trips; count++)
TRIP_POINT_ATTR_REMOVE(&tz->device, count);
thermal_remove_hwmon_sysfs(tz);
release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
idr_destroy(&tz->idr);
mutex_destroy(&tz->lock);
device_unregister(&tz->device);
return;
}
EXPORT_SYMBOL(thermal_zone_device_unregister);
static int __init thermal_init(void)
{
int result = 0;
result = class_register(&thermal_class);
if (result) {
idr_destroy(&thermal_tz_idr);
idr_destroy(&thermal_cdev_idr);
mutex_destroy(&thermal_idr_lock);
mutex_destroy(&thermal_list_lock);
}
return result;
}
static void __exit thermal_exit(void)
{
class_unregister(&thermal_class);
idr_destroy(&thermal_tz_idr);
idr_destroy(&thermal_cdev_idr);
mutex_destroy(&thermal_idr_lock);
mutex_destroy(&thermal_list_lock);
}
subsys_initcall(thermal_init);
module_exit(thermal_exit);