linux/drivers/thermal/thermal_core.c
Wei Wang 163b00cde7 thermal: Fix deadlock in thermal thermal_zone_device_check
1851799e1d ("thermal: Fix use-after-free when unregistering thermal zone
device") changed cancel_delayed_work to cancel_delayed_work_sync to avoid
a use-after-free issue. However, cancel_delayed_work_sync could be called
insides the WQ causing deadlock.

[54109.642398] c0   1162 kworker/u17:1   D    0 11030      2 0x00000000
[54109.642437] c0   1162 Workqueue: thermal_passive_wq thermal_zone_device_check
[54109.642447] c0   1162 Call trace:
[54109.642456] c0   1162  __switch_to+0x138/0x158
[54109.642467] c0   1162  __schedule+0xba4/0x1434
[54109.642480] c0   1162  schedule_timeout+0xa0/0xb28
[54109.642492] c0   1162  wait_for_common+0x138/0x2e8
[54109.642511] c0   1162  flush_work+0x348/0x40c
[54109.642522] c0   1162  __cancel_work_timer+0x180/0x218
[54109.642544] c0   1162  handle_thermal_trip+0x2c4/0x5a4
[54109.642553] c0   1162  thermal_zone_device_update+0x1b4/0x25c
[54109.642563] c0   1162  thermal_zone_device_check+0x18/0x24
[54109.642574] c0   1162  process_one_work+0x3cc/0x69c
[54109.642583] c0   1162  worker_thread+0x49c/0x7c0
[54109.642593] c0   1162  kthread+0x17c/0x1b0
[54109.642602] c0   1162  ret_from_fork+0x10/0x18
[54109.643051] c0   1162 kworker/u17:2   D    0 16245      2 0x00000000
[54109.643067] c0   1162 Workqueue: thermal_passive_wq thermal_zone_device_check
[54109.643077] c0   1162 Call trace:
[54109.643085] c0   1162  __switch_to+0x138/0x158
[54109.643095] c0   1162  __schedule+0xba4/0x1434
[54109.643104] c0   1162  schedule_timeout+0xa0/0xb28
[54109.643114] c0   1162  wait_for_common+0x138/0x2e8
[54109.643122] c0   1162  flush_work+0x348/0x40c
[54109.643131] c0   1162  __cancel_work_timer+0x180/0x218
[54109.643141] c0   1162  handle_thermal_trip+0x2c4/0x5a4
[54109.643150] c0   1162  thermal_zone_device_update+0x1b4/0x25c
[54109.643159] c0   1162  thermal_zone_device_check+0x18/0x24
[54109.643167] c0   1162  process_one_work+0x3cc/0x69c
[54109.643177] c0   1162  worker_thread+0x49c/0x7c0
[54109.643186] c0   1162  kthread+0x17c/0x1b0
[54109.643195] c0   1162  ret_from_fork+0x10/0x18
[54109.644500] c0   1162 cat             D    0  7766      1 0x00000001
[54109.644515] c0   1162 Call trace:
[54109.644524] c0   1162  __switch_to+0x138/0x158
[54109.644536] c0   1162  __schedule+0xba4/0x1434
[54109.644546] c0   1162  schedule_preempt_disabled+0x80/0xb0
[54109.644555] c0   1162  __mutex_lock+0x3a8/0x7f0
[54109.644563] c0   1162  __mutex_lock_slowpath+0x14/0x20
[54109.644575] c0   1162  thermal_zone_get_temp+0x84/0x360
[54109.644586] c0   1162  temp_show+0x30/0x78
[54109.644609] c0   1162  dev_attr_show+0x5c/0xf0
[54109.644628] c0   1162  sysfs_kf_seq_show+0xcc/0x1a4
[54109.644636] c0   1162  kernfs_seq_show+0x48/0x88
[54109.644656] c0   1162  seq_read+0x1f4/0x73c
[54109.644664] c0   1162  kernfs_fop_read+0x84/0x318
[54109.644683] c0   1162  __vfs_read+0x50/0x1bc
[54109.644692] c0   1162  vfs_read+0xa4/0x140
[54109.644701] c0   1162  SyS_read+0xbc/0x144
[54109.644708] c0   1162  el0_svc_naked+0x34/0x38
[54109.845800] c0   1162 D 720.000s 1->7766->7766 cat [panic]

Fixes: 1851799e1d ("thermal: Fix use-after-free when unregistering thermal zone device")
Cc: stable@vger.kernel.org
Signed-off-by: Wei Wang <wvw@google.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2019-11-14 22:41:09 +08:00

1541 lines
41 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* 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>
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/kdev_t.h>
#include <linux/idr.h>
#include <linux/thermal.h>
#include <linux/reboot.h>
#include <linux/string.h>
#include <linux/of.h>
#include <linux/suspend.h>
#define CREATE_TRACE_POINTS
#include <trace/events/thermal.h>
#include "thermal_core.h"
#include "thermal_hwmon.h"
MODULE_AUTHOR("Zhang Rui");
MODULE_DESCRIPTION("Generic thermal management sysfs support");
MODULE_LICENSE("GPL v2");
static DEFINE_IDA(thermal_tz_ida);
static DEFINE_IDA(thermal_cdev_ida);
static LIST_HEAD(thermal_tz_list);
static LIST_HEAD(thermal_cdev_list);
static LIST_HEAD(thermal_governor_list);
static DEFINE_MUTEX(thermal_list_lock);
static DEFINE_MUTEX(thermal_governor_lock);
static DEFINE_MUTEX(poweroff_lock);
static atomic_t in_suspend;
static bool power_off_triggered;
static struct thermal_governor *def_governor;
/*
* Governor section: set of functions to handle thermal governors
*
* Functions to help in the life cycle of thermal governors within
* the thermal core and by the thermal governor code.
*/
static struct thermal_governor *__find_governor(const char *name)
{
struct thermal_governor *pos;
if (!name || !name[0])
return def_governor;
list_for_each_entry(pos, &thermal_governor_list, governor_list)
if (!strncasecmp(name, pos->name, THERMAL_NAME_LENGTH))
return pos;
return NULL;
}
/**
* bind_previous_governor() - bind the previous governor of the thermal zone
* @tz: a valid pointer to a struct thermal_zone_device
* @failed_gov_name: the name of the governor that failed to register
*
* Register the previous governor of the thermal zone after a new
* governor has failed to be bound.
*/
static void bind_previous_governor(struct thermal_zone_device *tz,
const char *failed_gov_name)
{
if (tz->governor && tz->governor->bind_to_tz) {
if (tz->governor->bind_to_tz(tz)) {
dev_err(&tz->device,
"governor %s failed to bind and the previous one (%s) failed to bind again, thermal zone %s has no governor\n",
failed_gov_name, tz->governor->name, tz->type);
tz->governor = NULL;
}
}
}
/**
* thermal_set_governor() - Switch to another governor
* @tz: a valid pointer to a struct thermal_zone_device
* @new_gov: pointer to the new governor
*
* Change the governor of thermal zone @tz.
*
* Return: 0 on success, an error if the new governor's bind_to_tz() failed.
*/
static int thermal_set_governor(struct thermal_zone_device *tz,
struct thermal_governor *new_gov)
{
int ret = 0;
if (tz->governor && tz->governor->unbind_from_tz)
tz->governor->unbind_from_tz(tz);
if (new_gov && new_gov->bind_to_tz) {
ret = new_gov->bind_to_tz(tz);
if (ret) {
bind_previous_governor(tz, new_gov->name);
return ret;
}
}
tz->governor = new_gov;
return ret;
}
int thermal_register_governor(struct thermal_governor *governor)
{
int err;
const char *name;
struct thermal_zone_device *pos;
if (!governor)
return -EINVAL;
mutex_lock(&thermal_governor_lock);
err = -EBUSY;
if (!__find_governor(governor->name)) {
bool match_default;
err = 0;
list_add(&governor->governor_list, &thermal_governor_list);
match_default = !strncmp(governor->name,
DEFAULT_THERMAL_GOVERNOR,
THERMAL_NAME_LENGTH);
if (!def_governor && match_default)
def_governor = governor;
}
mutex_lock(&thermal_list_lock);
list_for_each_entry(pos, &thermal_tz_list, node) {
/*
* only thermal zones with specified tz->tzp->governor_name
* may run with tz->govenor unset
*/
if (pos->governor)
continue;
name = pos->tzp->governor_name;
if (!strncasecmp(name, governor->name, THERMAL_NAME_LENGTH)) {
int ret;
ret = thermal_set_governor(pos, governor);
if (ret)
dev_err(&pos->device,
"Failed to set governor %s for thermal zone %s: %d\n",
governor->name, pos->type, ret);
}
}
mutex_unlock(&thermal_list_lock);
mutex_unlock(&thermal_governor_lock);
return err;
}
void thermal_unregister_governor(struct thermal_governor *governor)
{
struct thermal_zone_device *pos;
if (!governor)
return;
mutex_lock(&thermal_governor_lock);
if (!__find_governor(governor->name))
goto exit;
mutex_lock(&thermal_list_lock);
list_for_each_entry(pos, &thermal_tz_list, node) {
if (!strncasecmp(pos->governor->name, governor->name,
THERMAL_NAME_LENGTH))
thermal_set_governor(pos, NULL);
}
mutex_unlock(&thermal_list_lock);
list_del(&governor->governor_list);
exit:
mutex_unlock(&thermal_governor_lock);
}
int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
char *policy)
{
struct thermal_governor *gov;
int ret = -EINVAL;
mutex_lock(&thermal_governor_lock);
mutex_lock(&tz->lock);
gov = __find_governor(strim(policy));
if (!gov)
goto exit;
ret = thermal_set_governor(tz, gov);
exit:
mutex_unlock(&tz->lock);
mutex_unlock(&thermal_governor_lock);
return ret;
}
int thermal_build_list_of_policies(char *buf)
{
struct thermal_governor *pos;
ssize_t count = 0;
ssize_t size = PAGE_SIZE;
mutex_lock(&thermal_governor_lock);
list_for_each_entry(pos, &thermal_governor_list, governor_list) {
size = PAGE_SIZE - count;
count += scnprintf(buf + count, size, "%s ", pos->name);
}
count += scnprintf(buf + count, size, "\n");
mutex_unlock(&thermal_governor_lock);
return count;
}
static void __init thermal_unregister_governors(void)
{
struct thermal_governor **governor;
for_each_governor_table(governor)
thermal_unregister_governor(*governor);
}
static int __init thermal_register_governors(void)
{
int ret = 0;
struct thermal_governor **governor;
for_each_governor_table(governor) {
ret = thermal_register_governor(*governor);
if (ret) {
pr_err("Failed to register governor: '%s'",
(*governor)->name);
break;
}
pr_info("Registered thermal governor '%s'",
(*governor)->name);
}
if (ret) {
struct thermal_governor **gov;
for_each_governor_table(gov) {
if (gov == governor)
break;
thermal_unregister_governor(*gov);
}
}
return ret;
}
/*
* Zone update section: main control loop applied to each zone while monitoring
*
* in polling mode. The monitoring is done using a workqueue.
* Same update may be done on a zone by calling thermal_zone_device_update().
*
* An update means:
* - Non-critical trips will invoke the governor responsible for that zone;
* - Hot trips will produce a notification to userspace;
* - Critical trip point will cause a system shutdown.
*/
static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
int delay)
{
if (delay > 1000)
mod_delayed_work(system_freezable_power_efficient_wq,
&tz->poll_queue,
round_jiffies(msecs_to_jiffies(delay)));
else if (delay)
mod_delayed_work(system_freezable_power_efficient_wq,
&tz->poll_queue,
msecs_to_jiffies(delay));
else
cancel_delayed_work(&tz->poll_queue);
}
static void monitor_thermal_zone(struct thermal_zone_device *tz)
{
mutex_lock(&tz->lock);
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);
else
thermal_zone_device_set_polling(tz, 0);
mutex_unlock(&tz->lock);
}
static void handle_non_critical_trips(struct thermal_zone_device *tz, int trip)
{
tz->governor ? tz->governor->throttle(tz, trip) :
def_governor->throttle(tz, trip);
}
/**
* thermal_emergency_poweroff_func - emergency poweroff work after a known delay
* @work: work_struct associated with the emergency poweroff function
*
* This function is called in very critical situations to force
* a kernel poweroff after a configurable timeout value.
*/
static void thermal_emergency_poweroff_func(struct work_struct *work)
{
/*
* We have reached here after the emergency thermal shutdown
* Waiting period has expired. This means orderly_poweroff has
* not been able to shut off the system for some reason.
* Try to shut down the system immediately using kernel_power_off
* if populated
*/
WARN(1, "Attempting kernel_power_off: Temperature too high\n");
kernel_power_off();
/*
* Worst of the worst case trigger emergency restart
*/
WARN(1, "Attempting emergency_restart: Temperature too high\n");
emergency_restart();
}
static DECLARE_DELAYED_WORK(thermal_emergency_poweroff_work,
thermal_emergency_poweroff_func);
/**
* thermal_emergency_poweroff - Trigger an emergency system poweroff
*
* This may be called from any critical situation to trigger a system shutdown
* after a known period of time. By default this is not scheduled.
*/
static void thermal_emergency_poweroff(void)
{
int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
/*
* poweroff_delay_ms must be a carefully profiled positive value.
* Its a must for thermal_emergency_poweroff_work to be scheduled
*/
if (poweroff_delay_ms <= 0)
return;
schedule_delayed_work(&thermal_emergency_poweroff_work,
msecs_to_jiffies(poweroff_delay_ms));
}
static void handle_critical_trips(struct thermal_zone_device *tz,
int trip, enum thermal_trip_type trip_type)
{
int trip_temp;
tz->ops->get_trip_temp(tz, trip, &trip_temp);
/* If we have not crossed the trip_temp, we do not care. */
if (trip_temp <= 0 || tz->temperature < trip_temp)
return;
trace_thermal_zone_trip(tz, trip, trip_type);
if (tz->ops->notify)
tz->ops->notify(tz, trip, trip_type);
if (trip_type == THERMAL_TRIP_CRITICAL) {
dev_emerg(&tz->device,
"critical temperature reached (%d C), shutting down\n",
tz->temperature / 1000);
mutex_lock(&poweroff_lock);
if (!power_off_triggered) {
/*
* Queue a backup emergency shutdown in the event of
* orderly_poweroff failure
*/
thermal_emergency_poweroff();
orderly_poweroff(true);
power_off_triggered = true;
}
mutex_unlock(&poweroff_lock);
}
}
static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
{
enum thermal_trip_type type;
/* Ignore disabled trip points */
if (test_bit(trip, &tz->trips_disabled))
return;
tz->ops->get_trip_type(tz, trip, &type);
if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
handle_critical_trips(tz, trip, type);
else
handle_non_critical_trips(tz, trip);
/*
* Alright, we handled this trip successfully.
* So, start monitoring again.
*/
monitor_thermal_zone(tz);
}
static void update_temperature(struct thermal_zone_device *tz)
{
int temp, ret;
ret = thermal_zone_get_temp(tz, &temp);
if (ret) {
if (ret != -EAGAIN)
dev_warn(&tz->device,
"failed to read out thermal zone (%d)\n",
ret);
return;
}
mutex_lock(&tz->lock);
tz->last_temperature = tz->temperature;
tz->temperature = temp;
mutex_unlock(&tz->lock);
trace_thermal_temperature(tz);
if (tz->last_temperature == THERMAL_TEMP_INVALID)
dev_dbg(&tz->device, "last_temperature N/A, current_temperature=%d\n",
tz->temperature);
else
dev_dbg(&tz->device, "last_temperature=%d, current_temperature=%d\n",
tz->last_temperature, tz->temperature);
}
static void thermal_zone_device_init(struct thermal_zone_device *tz)
{
struct thermal_instance *pos;
tz->temperature = THERMAL_TEMP_INVALID;
list_for_each_entry(pos, &tz->thermal_instances, tz_node)
pos->initialized = false;
}
static void thermal_zone_device_reset(struct thermal_zone_device *tz)
{
tz->passive = 0;
thermal_zone_device_init(tz);
}
void thermal_zone_device_update(struct thermal_zone_device *tz,
enum thermal_notify_event event)
{
int count;
if (atomic_read(&in_suspend))
return;
if (!tz->ops->get_temp)
return;
update_temperature(tz);
thermal_zone_set_trips(tz);
tz->notify_event = event;
for (count = 0; count < tz->trips; count++)
handle_thermal_trip(tz, count);
}
EXPORT_SYMBOL_GPL(thermal_zone_device_update);
/**
* thermal_notify_framework - Sensor drivers use this API to notify framework
* @tz: thermal zone device
* @trip: indicates which trip point has been crossed
*
* This function handles the trip events from sensor drivers. It starts
* throttling the cooling devices according to the policy configured.
* For CRITICAL and HOT trip points, this notifies the respective drivers,
* and does actual throttling for other trip points i.e ACTIVE and PASSIVE.
* The throttling policy is based on the configured platform data; if no
* platform data is provided, this uses the step_wise throttling policy.
*/
void thermal_notify_framework(struct thermal_zone_device *tz, int trip)
{
handle_thermal_trip(tz, trip);
}
EXPORT_SYMBOL_GPL(thermal_notify_framework);
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_EVENT_UNSPECIFIED);
}
/*
* Power actor section: interface to power actors to estimate power
*
* Set of functions used to interact to cooling devices that know
* how to estimate their devices power consumption.
*/
/**
* power_actor_get_max_power() - get the maximum power that a cdev can consume
* @cdev: pointer to &thermal_cooling_device
* @tz: a valid thermal zone device pointer
* @max_power: pointer in which to store the maximum power
*
* Calculate the maximum power consumption in milliwats that the
* cooling device can currently consume and store it in @max_power.
*
* Return: 0 on success, -EINVAL if @cdev doesn't support the
* power_actor API or -E* on other error.
*/
int power_actor_get_max_power(struct thermal_cooling_device *cdev,
struct thermal_zone_device *tz, u32 *max_power)
{
if (!cdev_is_power_actor(cdev))
return -EINVAL;
return cdev->ops->state2power(cdev, tz, 0, max_power);
}
/**
* power_actor_get_min_power() - get the mainimum power that a cdev can consume
* @cdev: pointer to &thermal_cooling_device
* @tz: a valid thermal zone device pointer
* @min_power: pointer in which to store the minimum power
*
* Calculate the minimum power consumption in milliwatts that the
* cooling device can currently consume and store it in @min_power.
*
* Return: 0 on success, -EINVAL if @cdev doesn't support the
* power_actor API or -E* on other error.
*/
int power_actor_get_min_power(struct thermal_cooling_device *cdev,
struct thermal_zone_device *tz, u32 *min_power)
{
unsigned long max_state;
int ret;
if (!cdev_is_power_actor(cdev))
return -EINVAL;
ret = cdev->ops->get_max_state(cdev, &max_state);
if (ret)
return ret;
return cdev->ops->state2power(cdev, tz, max_state, min_power);
}
/**
* power_actor_set_power() - limit the maximum power a cooling device consumes
* @cdev: pointer to &thermal_cooling_device
* @instance: thermal instance to update
* @power: the power in milliwatts
*
* Set the cooling device to consume at most @power milliwatts. The limit is
* expected to be a cap at the maximum power consumption.
*
* Return: 0 on success, -EINVAL if the cooling device does not
* implement the power actor API or -E* for other failures.
*/
int power_actor_set_power(struct thermal_cooling_device *cdev,
struct thermal_instance *instance, u32 power)
{
unsigned long state;
int ret;
if (!cdev_is_power_actor(cdev))
return -EINVAL;
ret = cdev->ops->power2state(cdev, instance->tz, power, &state);
if (ret)
return ret;
instance->target = state;
mutex_lock(&cdev->lock);
cdev->updated = false;
mutex_unlock(&cdev->lock);
thermal_cdev_update(cdev);
return 0;
}
void thermal_zone_device_rebind_exception(struct thermal_zone_device *tz,
const char *cdev_type, size_t size)
{
struct thermal_cooling_device *cdev = NULL;
mutex_lock(&thermal_list_lock);
list_for_each_entry(cdev, &thermal_cdev_list, node) {
/* skip non matching cdevs */
if (strncmp(cdev_type, cdev->type, size))
continue;
/* re binding the exception matching the type pattern */
thermal_zone_bind_cooling_device(tz, THERMAL_TRIPS_NONE, cdev,
THERMAL_NO_LIMIT,
THERMAL_NO_LIMIT,
THERMAL_WEIGHT_DEFAULT);
}
mutex_unlock(&thermal_list_lock);
}
void thermal_zone_device_unbind_exception(struct thermal_zone_device *tz,
const char *cdev_type, size_t size)
{
struct thermal_cooling_device *cdev = NULL;
mutex_lock(&thermal_list_lock);
list_for_each_entry(cdev, &thermal_cdev_list, node) {
/* skip non matching cdevs */
if (strncmp(cdev_type, cdev->type, size))
continue;
/* unbinding the exception matching the type pattern */
thermal_zone_unbind_cooling_device(tz, THERMAL_TRIPS_NONE,
cdev);
}
mutex_unlock(&thermal_list_lock);
}
/*
* Device management section: cooling devices, zones devices, and binding
*
* Set of functions provided by the thermal core for:
* - cooling devices lifecycle: registration, unregistration,
* binding, and unbinding.
* - thermal zone devices lifecycle: registration, unregistration,
* binding, and unbinding.
*/
/**
* thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
* @tz: pointer to struct thermal_zone_device
* @trip: indicates which trip point the cooling devices is
* associated with in this thermal zone.
* @cdev: pointer to struct thermal_cooling_device
* @upper: the Maximum cooling state for this trip point.
* THERMAL_NO_LIMIT means no upper limit,
* and the cooling device can be in max_state.
* @lower: the Minimum cooling state can be used for this trip point.
* THERMAL_NO_LIMIT means no lower limit,
* and the cooling device can be in cooling state 0.
* @weight: The weight of the cooling device to be bound to the
* thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
* default value
*
* This interface function bind a thermal cooling device to the certain trip
* point of a thermal zone device.
* This function is usually called in the thermal zone device .bind callback.
*
* Return: 0 on success, the proper error value otherwise.
*/
int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
int trip,
struct thermal_cooling_device *cdev,
unsigned long upper, unsigned long lower,
unsigned int weight)
{
struct thermal_instance *dev;
struct thermal_instance *pos;
struct thermal_zone_device *pos1;
struct thermal_cooling_device *pos2;
unsigned long max_state;
int result, ret;
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;
ret = cdev->ops->get_max_state(cdev, &max_state);
if (ret)
return ret;
/* 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(*dev), 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;
dev->weight = weight;
result = ida_simple_get(&tz->ida, 0, 0, GFP_KERNEL);
if (result < 0)
goto free_mem;
dev->id = result;
sprintf(dev->name, "cdev%d", dev->id);
result =
sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
if (result)
goto release_ida;
sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
sysfs_attr_init(&dev->attr.attr);
dev->attr.attr.name = dev->attr_name;
dev->attr.attr.mode = 0444;
dev->attr.show = trip_point_show;
result = device_create_file(&tz->device, &dev->attr);
if (result)
goto remove_symbol_link;
sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
sysfs_attr_init(&dev->weight_attr.attr);
dev->weight_attr.attr.name = dev->weight_attr_name;
dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
dev->weight_attr.show = weight_show;
dev->weight_attr.store = weight_store;
result = device_create_file(&tz->device, &dev->weight_attr);
if (result)
goto remove_trip_file;
mutex_lock(&tz->lock);
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->tz_node, &tz->thermal_instances);
list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
atomic_set(&tz->need_update, 1);
}
mutex_unlock(&cdev->lock);
mutex_unlock(&tz->lock);
if (!result)
return 0;
device_remove_file(&tz->device, &dev->weight_attr);
remove_trip_file:
device_remove_file(&tz->device, &dev->attr);
remove_symbol_link:
sysfs_remove_link(&tz->device.kobj, dev->name);
release_ida:
ida_simple_remove(&tz->ida, dev->id);
free_mem:
kfree(dev);
return result;
}
EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
/**
* thermal_zone_unbind_cooling_device() - unbind a cooling device from a
* thermal zone.
* @tz: pointer to a struct thermal_zone_device.
* @trip: indicates which trip point the cooling devices is
* associated with in this thermal zone.
* @cdev: pointer to a struct thermal_cooling_device.
*
* This interface function unbind a thermal cooling device from the certain
* trip point of a thermal zone device.
* This function is usually called in the thermal zone device .unbind callback.
*
* Return: 0 on success, the proper error value otherwise.
*/
int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
int trip,
struct thermal_cooling_device *cdev)
{
struct thermal_instance *pos, *next;
mutex_lock(&tz->lock);
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->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;
unbind:
device_remove_file(&tz->device, &pos->weight_attr);
device_remove_file(&tz->device, &pos->attr);
sysfs_remove_link(&tz->device.kobj, pos->name);
ida_simple_remove(&tz->ida, pos->id);
kfree(pos);
return 0;
}
EXPORT_SYMBOL_GPL(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);
thermal_zone_destroy_device_groups(tz);
kfree(tz);
} else if (!strncmp(dev_name(dev), "cooling_device",
sizeof("cooling_device") - 1)) {
cdev = to_cooling_device(dev);
kfree(cdev);
}
}
static struct class thermal_class = {
.name = "thermal",
.dev_release = thermal_release,
};
static inline
void print_bind_err_msg(struct thermal_zone_device *tz,
struct thermal_cooling_device *cdev, int ret)
{
dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
tz->type, cdev->type, ret);
}
static void __bind(struct thermal_zone_device *tz, int mask,
struct thermal_cooling_device *cdev,
unsigned long *limits,
unsigned int weight)
{
int i, ret;
for (i = 0; i < tz->trips; i++) {
if (mask & (1 << i)) {
unsigned long upper, lower;
upper = THERMAL_NO_LIMIT;
lower = THERMAL_NO_LIMIT;
if (limits) {
lower = limits[i * 2];
upper = limits[i * 2 + 1];
}
ret = thermal_zone_bind_cooling_device(tz, i, cdev,
upper, lower,
weight);
if (ret)
print_bind_err_msg(tz, cdev, ret);
}
}
}
static void bind_cdev(struct thermal_cooling_device *cdev)
{
int i, ret;
const struct thermal_zone_params *tzp;
struct thermal_zone_device *pos = NULL;
mutex_lock(&thermal_list_lock);
list_for_each_entry(pos, &thermal_tz_list, node) {
if (!pos->tzp && !pos->ops->bind)
continue;
if (pos->ops->bind) {
ret = pos->ops->bind(pos, cdev);
if (ret)
print_bind_err_msg(pos, cdev, ret);
continue;
}
tzp = pos->tzp;
if (!tzp || !tzp->tbp)
continue;
for (i = 0; i < tzp->num_tbps; i++) {
if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
continue;
if (tzp->tbp[i].match(pos, cdev))
continue;
tzp->tbp[i].cdev = cdev;
__bind(pos, tzp->tbp[i].trip_mask, cdev,
tzp->tbp[i].binding_limits,
tzp->tbp[i].weight);
}
}
mutex_unlock(&thermal_list_lock);
}
/**
* __thermal_cooling_device_register() - register a new thermal cooling device
* @np: a pointer to a device tree node.
* @type: the thermal cooling device type.
* @devdata: device private data.
* @ops: standard thermal cooling devices callbacks.
*
* This interface function adds a new thermal cooling device (fan/processor/...)
* to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
* to all the thermal zone devices registered at the same time.
* It also gives the opportunity to link the cooling device to a device tree
* node, so that it can be bound to a thermal zone created out of device tree.
*
* Return: a pointer to the created struct thermal_cooling_device or an
* ERR_PTR. Caller must check return value with IS_ERR*() helpers.
*/
static struct thermal_cooling_device *
__thermal_cooling_device_register(struct device_node *np,
const char *type, void *devdata,
const struct thermal_cooling_device_ops *ops)
{
struct thermal_cooling_device *cdev;
struct thermal_zone_device *pos = NULL;
int result;
if (type && 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(*cdev), GFP_KERNEL);
if (!cdev)
return ERR_PTR(-ENOMEM);
result = ida_simple_get(&thermal_cdev_ida, 0, 0, GFP_KERNEL);
if (result < 0) {
kfree(cdev);
return ERR_PTR(result);
}
cdev->id = result;
strlcpy(cdev->type, type ? : "", sizeof(cdev->type));
mutex_init(&cdev->lock);
INIT_LIST_HEAD(&cdev->thermal_instances);
cdev->np = np;
cdev->ops = ops;
cdev->updated = false;
cdev->device.class = &thermal_class;
cdev->devdata = devdata;
thermal_cooling_device_setup_sysfs(cdev);
dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
result = device_register(&cdev->device);
if (result) {
ida_simple_remove(&thermal_cdev_ida, cdev->id);
put_device(&cdev->device);
return ERR_PTR(result);
}
/* Add 'this' new cdev to the global cdev list */
mutex_lock(&thermal_list_lock);
list_add(&cdev->node, &thermal_cdev_list);
mutex_unlock(&thermal_list_lock);
/* Update binding information for 'this' new cdev */
bind_cdev(cdev);
mutex_lock(&thermal_list_lock);
list_for_each_entry(pos, &thermal_tz_list, node)
if (atomic_cmpxchg(&pos->need_update, 1, 0))
thermal_zone_device_update(pos,
THERMAL_EVENT_UNSPECIFIED);
mutex_unlock(&thermal_list_lock);
return cdev;
}
/**
* 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.
*
* This interface function adds a new thermal cooling device (fan/processor/...)
* to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
* to all the thermal zone devices registered at the same time.
*
* Return: a pointer to the created struct thermal_cooling_device or an
* ERR_PTR. Caller must check return value with IS_ERR*() helpers.
*/
struct thermal_cooling_device *
thermal_cooling_device_register(const char *type, void *devdata,
const struct thermal_cooling_device_ops *ops)
{
return __thermal_cooling_device_register(NULL, type, devdata, ops);
}
EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
/**
* thermal_of_cooling_device_register() - register an OF thermal cooling device
* @np: a pointer to a device tree node.
* @type: the thermal cooling device type.
* @devdata: device private data.
* @ops: standard thermal cooling devices callbacks.
*
* This function will register a cooling device with device tree node reference.
* This interface function adds a new thermal cooling device (fan/processor/...)
* to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
* to all the thermal zone devices registered at the same time.
*
* Return: a pointer to the created struct thermal_cooling_device or an
* ERR_PTR. Caller must check return value with IS_ERR*() helpers.
*/
struct thermal_cooling_device *
thermal_of_cooling_device_register(struct device_node *np,
const char *type, void *devdata,
const struct thermal_cooling_device_ops *ops)
{
return __thermal_cooling_device_register(np, type, devdata, ops);
}
EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
static void thermal_cooling_device_release(struct device *dev, void *res)
{
thermal_cooling_device_unregister(
*(struct thermal_cooling_device **)res);
}
/**
* devm_thermal_of_cooling_device_register() - register an OF thermal cooling
* device
* @dev: a valid struct device pointer of a sensor device.
* @np: a pointer to a device tree node.
* @type: the thermal cooling device type.
* @devdata: device private data.
* @ops: standard thermal cooling devices callbacks.
*
* This function will register a cooling device with device tree node reference.
* This interface function adds a new thermal cooling device (fan/processor/...)
* to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
* to all the thermal zone devices registered at the same time.
*
* Return: a pointer to the created struct thermal_cooling_device or an
* ERR_PTR. Caller must check return value with IS_ERR*() helpers.
*/
struct thermal_cooling_device *
devm_thermal_of_cooling_device_register(struct device *dev,
struct device_node *np,
char *type, void *devdata,
const struct thermal_cooling_device_ops *ops)
{
struct thermal_cooling_device **ptr, *tcd;
ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
GFP_KERNEL);
if (!ptr)
return ERR_PTR(-ENOMEM);
tcd = __thermal_cooling_device_register(np, type, devdata, ops);
if (IS_ERR(tcd)) {
devres_free(ptr);
return tcd;
}
*ptr = tcd;
devres_add(dev, ptr);
return tcd;
}
EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
static void __unbind(struct thermal_zone_device *tz, int mask,
struct thermal_cooling_device *cdev)
{
int i;
for (i = 0; i < tz->trips; i++)
if (mask & (1 << i))
thermal_zone_unbind_cooling_device(tz, i, cdev);
}
/**
* thermal_cooling_device_unregister - removes a thermal cooling device
* @cdev: the thermal cooling device to remove.
*
* thermal_cooling_device_unregister() must be called when a registered
* thermal cooling device is no longer needed.
*/
void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
{
int i;
const struct thermal_zone_params *tzp;
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);
/* Unbind all thermal zones associated with 'this' cdev */
list_for_each_entry(tz, &thermal_tz_list, node) {
if (tz->ops->unbind) {
tz->ops->unbind(tz, cdev);
continue;
}
if (!tz->tzp || !tz->tzp->tbp)
continue;
tzp = tz->tzp;
for (i = 0; i < tzp->num_tbps; i++) {
if (tzp->tbp[i].cdev == cdev) {
__unbind(tz, tzp->tbp[i].trip_mask, cdev);
tzp->tbp[i].cdev = NULL;
}
}
}
mutex_unlock(&thermal_list_lock);
ida_simple_remove(&thermal_cdev_ida, cdev->id);
device_del(&cdev->device);
thermal_cooling_device_destroy_sysfs(cdev);
put_device(&cdev->device);
}
EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
static void bind_tz(struct thermal_zone_device *tz)
{
int i, ret;
struct thermal_cooling_device *pos = NULL;
const struct thermal_zone_params *tzp = tz->tzp;
if (!tzp && !tz->ops->bind)
return;
mutex_lock(&thermal_list_lock);
/* If there is ops->bind, try to use ops->bind */
if (tz->ops->bind) {
list_for_each_entry(pos, &thermal_cdev_list, node) {
ret = tz->ops->bind(tz, pos);
if (ret)
print_bind_err_msg(tz, pos, ret);
}
goto exit;
}
if (!tzp || !tzp->tbp)
goto exit;
list_for_each_entry(pos, &thermal_cdev_list, node) {
for (i = 0; i < tzp->num_tbps; i++) {
if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
continue;
if (tzp->tbp[i].match(tz, pos))
continue;
tzp->tbp[i].cdev = pos;
__bind(tz, tzp->tbp[i].trip_mask, pos,
tzp->tbp[i].binding_limits,
tzp->tbp[i].weight);
}
}
exit:
mutex_unlock(&thermal_list_lock);
}
/**
* 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
* @mask: a bit string indicating the writeablility of trip points
* @devdata: private device data
* @ops: standard thermal zone device callbacks
* @tzp: thermal zone platform parameters
* @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)
*
* This interface function adds a new thermal zone device (sensor) to
* /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
* thermal cooling devices registered at the same time.
* thermal_zone_device_unregister() must be called when the device is no
* longer needed. The passive cooling depends on the .get_trend() return value.
*
* Return: a pointer to the created struct thermal_zone_device or an
* in case of error, an ERR_PTR. Caller must check return value with
* IS_ERR*() helpers.
*/
struct thermal_zone_device *
thermal_zone_device_register(const char *type, int trips, int mask,
void *devdata, struct thermal_zone_device_ops *ops,
struct thermal_zone_params *tzp, int passive_delay,
int polling_delay)
{
struct thermal_zone_device *tz;
enum thermal_trip_type trip_type;
int trip_temp;
int id;
int result;
int count;
struct thermal_governor *governor;
if (!type || strlen(type) == 0) {
pr_err("Error: No thermal zone type defined\n");
return ERR_PTR(-EINVAL);
}
if (type && strlen(type) >= THERMAL_NAME_LENGTH) {
pr_err("Error: Thermal zone name (%s) too long, should be under %d chars\n",
type, THERMAL_NAME_LENGTH);
return ERR_PTR(-EINVAL);
}
if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips) {
pr_err("Error: Incorrect number of thermal trips\n");
return ERR_PTR(-EINVAL);
}
if (!ops) {
pr_err("Error: Thermal zone device ops not defined\n");
return ERR_PTR(-EINVAL);
}
if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
return ERR_PTR(-EINVAL);
tz = kzalloc(sizeof(*tz), GFP_KERNEL);
if (!tz)
return ERR_PTR(-ENOMEM);
INIT_LIST_HEAD(&tz->thermal_instances);
ida_init(&tz->ida);
mutex_init(&tz->lock);
id = ida_simple_get(&thermal_tz_ida, 0, 0, GFP_KERNEL);
if (id < 0) {
result = id;
goto free_tz;
}
tz->id = id;
strlcpy(tz->type, type, sizeof(tz->type));
tz->ops = ops;
tz->tzp = tzp;
tz->device.class = &thermal_class;
tz->devdata = devdata;
tz->trips = trips;
tz->passive_delay = passive_delay;
tz->polling_delay = polling_delay;
/* sys I/F */
/* Add nodes that are always present via .groups */
result = thermal_zone_create_device_groups(tz, mask);
if (result)
goto remove_id;
/* A new thermal zone needs to be updated anyway. */
atomic_set(&tz->need_update, 1);
dev_set_name(&tz->device, "thermal_zone%d", tz->id);
result = device_register(&tz->device);
if (result)
goto release_device;
for (count = 0; count < trips; count++) {
if (tz->ops->get_trip_type(tz, count, &trip_type))
set_bit(count, &tz->trips_disabled);
if (tz->ops->get_trip_temp(tz, count, &trip_temp))
set_bit(count, &tz->trips_disabled);
/* Check for bogus trip points */
if (trip_temp == 0)
set_bit(count, &tz->trips_disabled);
}
/* Update 'this' zone's governor information */
mutex_lock(&thermal_governor_lock);
if (tz->tzp)
governor = __find_governor(tz->tzp->governor_name);
else
governor = def_governor;
result = thermal_set_governor(tz, governor);
if (result) {
mutex_unlock(&thermal_governor_lock);
goto unregister;
}
mutex_unlock(&thermal_governor_lock);
if (!tz->tzp || !tz->tzp->no_hwmon) {
result = thermal_add_hwmon_sysfs(tz);
if (result)
goto unregister;
}
mutex_lock(&thermal_list_lock);
list_add_tail(&tz->node, &thermal_tz_list);
mutex_unlock(&thermal_list_lock);
/* Bind cooling devices for this zone */
bind_tz(tz);
INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
thermal_zone_device_reset(tz);
/* Update the new thermal zone and mark it as already updated. */
if (atomic_cmpxchg(&tz->need_update, 1, 0))
thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
return tz;
unregister:
device_del(&tz->device);
release_device:
put_device(&tz->device);
tz = NULL;
remove_id:
ida_simple_remove(&thermal_tz_ida, id);
free_tz:
kfree(tz);
return ERR_PTR(result);
}
EXPORT_SYMBOL_GPL(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)
{
int i;
const struct thermal_zone_params *tzp;
struct thermal_cooling_device *cdev;
struct thermal_zone_device *pos = NULL;
if (!tz)
return;
tzp = tz->tzp;
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);
/* Unbind all cdevs associated with 'this' thermal zone */
list_for_each_entry(cdev, &thermal_cdev_list, node) {
if (tz->ops->unbind) {
tz->ops->unbind(tz, cdev);
continue;
}
if (!tzp || !tzp->tbp)
break;
for (i = 0; i < tzp->num_tbps; i++) {
if (tzp->tbp[i].cdev == cdev) {
__unbind(tz, tzp->tbp[i].trip_mask, cdev);
tzp->tbp[i].cdev = NULL;
}
}
}
mutex_unlock(&thermal_list_lock);
cancel_delayed_work_sync(&tz->poll_queue);
thermal_set_governor(tz, NULL);
thermal_remove_hwmon_sysfs(tz);
ida_simple_remove(&thermal_tz_ida, tz->id);
ida_destroy(&tz->ida);
mutex_destroy(&tz->lock);
device_unregister(&tz->device);
}
EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
/**
* thermal_zone_get_zone_by_name() - search for a zone and returns its ref
* @name: thermal zone name to fetch the temperature
*
* When only one zone is found with the passed name, returns a reference to it.
*
* Return: On success returns a reference to an unique thermal zone with
* matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
* paramenters, -ENODEV for not found and -EEXIST for multiple matches).
*/
struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
{
struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
unsigned int found = 0;
if (!name)
goto exit;
mutex_lock(&thermal_list_lock);
list_for_each_entry(pos, &thermal_tz_list, node)
if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
found++;
ref = pos;
}
mutex_unlock(&thermal_list_lock);
/* nothing has been found, thus an error code for it */
if (found == 0)
ref = ERR_PTR(-ENODEV);
else if (found > 1)
/* Success only when an unique zone is found */
ref = ERR_PTR(-EEXIST);
exit:
return ref;
}
EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
static int thermal_pm_notify(struct notifier_block *nb,
unsigned long mode, void *_unused)
{
struct thermal_zone_device *tz;
enum thermal_device_mode tz_mode;
switch (mode) {
case PM_HIBERNATION_PREPARE:
case PM_RESTORE_PREPARE:
case PM_SUSPEND_PREPARE:
atomic_set(&in_suspend, 1);
break;
case PM_POST_HIBERNATION:
case PM_POST_RESTORE:
case PM_POST_SUSPEND:
atomic_set(&in_suspend, 0);
list_for_each_entry(tz, &thermal_tz_list, node) {
tz_mode = THERMAL_DEVICE_ENABLED;
if (tz->ops->get_mode)
tz->ops->get_mode(tz, &tz_mode);
if (tz_mode == THERMAL_DEVICE_DISABLED)
continue;
thermal_zone_device_init(tz);
thermal_zone_device_update(tz,
THERMAL_EVENT_UNSPECIFIED);
}
break;
default:
break;
}
return 0;
}
static struct notifier_block thermal_pm_nb = {
.notifier_call = thermal_pm_notify,
};
static int __init thermal_init(void)
{
int result;
mutex_init(&poweroff_lock);
result = thermal_register_governors();
if (result)
goto error;
result = class_register(&thermal_class);
if (result)
goto unregister_governors;
result = of_parse_thermal_zones();
if (result)
goto unregister_class;
result = register_pm_notifier(&thermal_pm_nb);
if (result)
pr_warn("Thermal: Can not register suspend notifier, return %d\n",
result);
return 0;
unregister_class:
class_unregister(&thermal_class);
unregister_governors:
thermal_unregister_governors();
error:
ida_destroy(&thermal_tz_ida);
ida_destroy(&thermal_cdev_ida);
mutex_destroy(&thermal_list_lock);
mutex_destroy(&thermal_governor_lock);
mutex_destroy(&poweroff_lock);
return result;
}
core_initcall(thermal_init);