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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/thermal/thermal_core.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/thermal/thermal_core.c')
-rw-r--r--drivers/thermal/thermal_core.c1512
1 files changed, 1512 insertions, 0 deletions
diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
new file mode 100644
index 000000000..ebb36b2c7
--- /dev/null
+++ b/drivers/thermal/thermal_core.c
@@ -0,0 +1,1512 @@
+// 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/device.h>
+#include <linux/err.h>
+#include <linux/export.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"
+
+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 atomic_t in_suspend;
+
+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);
+
+ thermal_notify_tz_gov_change(tz->id, policy);
+
+ return ret;
+}
+
+int thermal_build_list_of_policies(char *buf)
+{
+ struct thermal_governor *pos;
+ ssize_t count = 0;
+
+ mutex_lock(&thermal_governor_lock);
+
+ list_for_each_entry(pos, &thermal_governor_list, governor_list) {
+ count += scnprintf(buf + count, PAGE_SIZE - count, "%s ",
+ pos->name);
+ }
+ count += scnprintf(buf + count, PAGE_SIZE - count, "\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,
+ unsigned long delay)
+{
+ if (delay)
+ mod_delayed_work(system_freezable_power_efficient_wq,
+ &tz->poll_queue, delay);
+ else
+ cancel_delayed_work(&tz->poll_queue);
+}
+
+static void monitor_thermal_zone(struct thermal_zone_device *tz)
+{
+ if (tz->mode != THERMAL_DEVICE_ENABLED)
+ thermal_zone_device_set_polling(tz, 0);
+ else if (tz->passive)
+ thermal_zone_device_set_polling(tz, tz->passive_delay_jiffies);
+ else if (tz->polling_delay_jiffies)
+ thermal_zone_device_set_polling(tz, tz->polling_delay_jiffies);
+}
+
+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);
+}
+
+void thermal_zone_device_critical(struct thermal_zone_device *tz)
+{
+ /*
+ * poweroff_delay_ms must be a carefully profiled positive value.
+ * Its a must for forced_emergency_poweroff_work to be scheduled.
+ */
+ int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
+
+ dev_emerg(&tz->device, "%s: critical temperature reached, "
+ "shutting down\n", tz->type);
+
+ hw_protection_shutdown("Temperature too high", poweroff_delay_ms);
+}
+EXPORT_SYMBOL(thermal_zone_device_critical);
+
+static void handle_critical_trips(struct thermal_zone_device *tz,
+ int trip, int trip_temp, enum thermal_trip_type trip_type)
+{
+ /* 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 (trip_type == THERMAL_TRIP_HOT && tz->ops->hot)
+ tz->ops->hot(tz);
+ else if (trip_type == THERMAL_TRIP_CRITICAL)
+ tz->ops->critical(tz);
+}
+
+static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
+{
+ enum thermal_trip_type type;
+ int trip_temp, hyst = 0;
+
+ /* Ignore disabled trip points */
+ if (test_bit(trip, &tz->trips_disabled))
+ return;
+
+ tz->ops->get_trip_temp(tz, trip, &trip_temp);
+ tz->ops->get_trip_type(tz, trip, &type);
+ if (tz->ops->get_trip_hyst)
+ tz->ops->get_trip_hyst(tz, trip, &hyst);
+
+ if (tz->last_temperature != THERMAL_TEMP_INVALID) {
+ if (tz->last_temperature < trip_temp &&
+ tz->temperature >= trip_temp)
+ thermal_notify_tz_trip_up(tz->id, trip,
+ tz->temperature);
+ if (tz->last_temperature >= trip_temp &&
+ tz->temperature < (trip_temp - hyst))
+ thermal_notify_tz_trip_down(tz->id, trip,
+ tz->temperature);
+ }
+
+ if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
+ handle_critical_trips(tz, trip, trip_temp, type);
+ else
+ handle_non_critical_trips(tz, trip);
+}
+
+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;
+ }
+
+ tz->last_temperature = tz->temperature;
+ tz->temperature = temp;
+
+ trace_thermal_temperature(tz);
+
+ thermal_genl_sampling_temp(tz->id, temp);
+}
+
+static void thermal_zone_device_init(struct thermal_zone_device *tz)
+{
+ struct thermal_instance *pos;
+ tz->temperature = THERMAL_TEMP_INVALID;
+ tz->prev_low_trip = -INT_MAX;
+ tz->prev_high_trip = INT_MAX;
+ list_for_each_entry(pos, &tz->thermal_instances, tz_node)
+ pos->initialized = false;
+}
+
+static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
+ enum thermal_device_mode mode)
+{
+ int ret = 0;
+
+ mutex_lock(&tz->lock);
+
+ /* do nothing if mode isn't changing */
+ if (mode == tz->mode) {
+ mutex_unlock(&tz->lock);
+
+ return ret;
+ }
+
+ if (tz->ops->change_mode)
+ ret = tz->ops->change_mode(tz, mode);
+
+ if (!ret)
+ tz->mode = mode;
+
+ mutex_unlock(&tz->lock);
+
+ thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
+
+ if (mode == THERMAL_DEVICE_ENABLED)
+ thermal_notify_tz_enable(tz->id);
+ else
+ thermal_notify_tz_disable(tz->id);
+
+ return ret;
+}
+
+int thermal_zone_device_enable(struct thermal_zone_device *tz)
+{
+ return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_ENABLED);
+}
+EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
+
+int thermal_zone_device_disable(struct thermal_zone_device *tz)
+{
+ return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
+}
+EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
+
+int thermal_zone_device_is_enabled(struct thermal_zone_device *tz)
+{
+ lockdep_assert_held(&tz->lock);
+
+ return tz->mode == THERMAL_DEVICE_ENABLED;
+}
+
+void thermal_zone_device_update(struct thermal_zone_device *tz,
+ enum thermal_notify_event event)
+{
+ int count;
+
+ if (atomic_read(&in_suspend))
+ return;
+
+ if (WARN_ONCE(!tz->ops->get_temp, "'%s' must not be called without "
+ "'get_temp' ops set\n", __func__))
+ return;
+
+ mutex_lock(&tz->lock);
+
+ if (!thermal_zone_device_is_enabled(tz))
+ goto out;
+
+ update_temperature(tz);
+
+ __thermal_zone_set_trips(tz);
+
+ tz->notify_event = event;
+
+ for (count = 0; count < tz->num_trips; count++)
+ handle_thermal_trip(tz, count);
+
+ monitor_thermal_zone(tz);
+out:
+ mutex_unlock(&tz->lock);
+}
+EXPORT_SYMBOL_GPL(thermal_zone_device_update);
+
+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);
+}
+
+int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
+ void *data)
+{
+ struct thermal_governor *gov;
+ int ret = 0;
+
+ mutex_lock(&thermal_governor_lock);
+ list_for_each_entry(gov, &thermal_governor_list, governor_list) {
+ ret = cb(gov, data);
+ if (ret)
+ break;
+ }
+ mutex_unlock(&thermal_governor_lock);
+
+ return ret;
+}
+
+int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
+ void *), void *data)
+{
+ struct thermal_cooling_device *cdev;
+ int ret = 0;
+
+ mutex_lock(&thermal_list_lock);
+ list_for_each_entry(cdev, &thermal_cdev_list, node) {
+ ret = cb(cdev, data);
+ if (ret)
+ break;
+ }
+ mutex_unlock(&thermal_list_lock);
+
+ return ret;
+}
+
+int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
+ void *data)
+{
+ struct thermal_zone_device *tz;
+ int ret = 0;
+
+ mutex_lock(&thermal_list_lock);
+ list_for_each_entry(tz, &thermal_tz_list, node) {
+ ret = cb(tz, data);
+ if (ret)
+ break;
+ }
+ mutex_unlock(&thermal_list_lock);
+
+ return ret;
+}
+
+struct thermal_zone_device *thermal_zone_get_by_id(int id)
+{
+ struct thermal_zone_device *tz, *match = NULL;
+
+ mutex_lock(&thermal_list_lock);
+ list_for_each_entry(tz, &thermal_tz_list, node) {
+ if (tz->id == id) {
+ match = tz;
+ break;
+ }
+ }
+ mutex_unlock(&thermal_list_lock);
+
+ return match;
+}
+
+/*
+ * 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;
+ int result;
+
+ if (trip >= tz->num_trips || trip < 0)
+ 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;
+
+ /* lower default 0, upper default max_state */
+ lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
+ upper = upper == THERMAL_NO_LIMIT ? cdev->max_state : upper;
+
+ if (lower > upper || upper > cdev->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_alloc(&tz->ida, 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;
+
+ snprintf(dev->attr_name, sizeof(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;
+
+ snprintf(dev->weight_attr_name, sizeof(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_free(&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_free(&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->num_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 id, ret;
+
+ 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);
+
+ ret = ida_alloc(&thermal_cdev_ida, GFP_KERNEL);
+ if (ret < 0)
+ goto out_kfree_cdev;
+ cdev->id = ret;
+ id = ret;
+
+ cdev->type = kstrdup(type ? type : "", GFP_KERNEL);
+ if (!cdev->type) {
+ ret = -ENOMEM;
+ goto out_ida_remove;
+ }
+
+ 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;
+
+ ret = cdev->ops->get_max_state(cdev, &cdev->max_state);
+ if (ret) {
+ kfree(cdev->type);
+ goto out_ida_remove;
+ }
+
+ thermal_cooling_device_setup_sysfs(cdev);
+
+ ret = dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
+ if (ret) {
+ kfree(cdev->type);
+ thermal_cooling_device_destroy_sysfs(cdev);
+ goto out_ida_remove;
+ }
+
+ ret = device_register(&cdev->device);
+ if (ret)
+ goto out_kfree_type;
+
+ /* 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;
+
+out_kfree_type:
+ thermal_cooling_device_destroy_sysfs(cdev);
+ kfree(cdev->type);
+ put_device(&cdev->device);
+
+ /* thermal_release() takes care of the rest */
+ cdev = NULL;
+out_ida_remove:
+ ida_free(&thermal_cdev_ida, id);
+out_kfree_cdev:
+ kfree(cdev);
+ return ERR_PTR(ret);
+}
+
+/**
+ * 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->num_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_free(&thermal_cdev_ida, cdev->id);
+ device_del(&cdev->device);
+ thermal_cooling_device_destroy_sysfs(cdev);
+ kfree(cdev->type);
+ 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);
+}
+
+static void thermal_set_delay_jiffies(unsigned long *delay_jiffies, int delay_ms)
+{
+ *delay_jiffies = msecs_to_jiffies(delay_ms);
+ if (delay_ms > 1000)
+ *delay_jiffies = round_jiffies(*delay_jiffies);
+}
+
+/**
+ * thermal_zone_device_register_with_trips() - register a new thermal zone device
+ * @type: the thermal zone device type
+ * @trips: a pointer to an array of thermal trips
+ * @num_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_with_trips(const char *type, struct thermal_trip *trips, int num_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("No thermal zone type defined\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ if (strlen(type) >= THERMAL_NAME_LENGTH) {
+ pr_err("Thermal zone name (%s) too long, should be under %d chars\n",
+ type, THERMAL_NAME_LENGTH);
+ return ERR_PTR(-EINVAL);
+ }
+
+ /*
+ * Max trip count can't exceed 31 as the "mask >> num_trips" condition.
+ * For example, shifting by 32 will result in compiler warning:
+ * warning: right shift count >= width of type [-Wshift-count- overflow]
+ *
+ * Also "mask >> num_trips" will always be true with 32 bit shift.
+ * E.g. mask = 0x80000000 for trip id 31 to be RW. Then
+ * mask >> 32 = 0x80000000
+ * This will result in failure for the below condition.
+ *
+ * Check will be true when the bit 31 of the mask is set.
+ * 32 bit shift will cause overflow of 4 byte integer.
+ */
+ if (num_trips > (BITS_PER_TYPE(int) - 1) || num_trips < 0 || mask >> num_trips) {
+ pr_err("Incorrect number of thermal trips\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ if (!ops) {
+ pr_err("Thermal zone device ops not defined\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ if (num_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_alloc(&thermal_tz_ida, GFP_KERNEL);
+ if (id < 0) {
+ result = id;
+ goto free_tz;
+ }
+
+ tz->id = id;
+ strscpy(tz->type, type, sizeof(tz->type));
+
+ if (!ops->critical)
+ ops->critical = thermal_zone_device_critical;
+
+ tz->ops = ops;
+ tz->tzp = tzp;
+ tz->device.class = &thermal_class;
+ tz->devdata = devdata;
+ tz->trips = trips;
+ tz->num_trips = num_trips;
+
+ thermal_set_delay_jiffies(&tz->passive_delay_jiffies, passive_delay);
+ thermal_set_delay_jiffies(&tz->polling_delay_jiffies, 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);
+
+ result = dev_set_name(&tz->device, "thermal_zone%d", tz->id);
+ if (result) {
+ thermal_zone_destroy_device_groups(tz);
+ goto remove_id;
+ }
+ result = device_register(&tz->device);
+ if (result)
+ goto release_device;
+
+ for (count = 0; count < num_trips; count++) {
+ if (tz->ops->get_trip_type(tz, count, &trip_type) ||
+ tz->ops->get_trip_temp(tz, count, &trip_temp) ||
+ !trip_temp)
+ 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_init(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);
+
+ thermal_notify_tz_create(tz->id, tz->type);
+
+ return tz;
+
+unregister:
+ device_del(&tz->device);
+release_device:
+ put_device(&tz->device);
+ tz = NULL;
+remove_id:
+ ida_free(&thermal_tz_ida, id);
+free_tz:
+ kfree(tz);
+ return ERR_PTR(result);
+}
+EXPORT_SYMBOL_GPL(thermal_zone_device_register_with_trips);
+
+struct thermal_zone_device *thermal_zone_device_register(const char *type, int ntrips, int mask,
+ void *devdata, struct thermal_zone_device_ops *ops,
+ struct thermal_zone_params *tzp, int passive_delay,
+ int polling_delay)
+{
+ return thermal_zone_device_register_with_trips(type, NULL, ntrips, mask,
+ devdata, ops, tzp,
+ passive_delay, polling_delay);
+}
+EXPORT_SYMBOL_GPL(thermal_zone_device_register);
+
+/**
+ * thermal_zone_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, tz_id;
+ const struct thermal_zone_params *tzp;
+ struct thermal_cooling_device *cdev;
+ struct thermal_zone_device *pos = NULL;
+
+ if (!tz)
+ return;
+
+ tzp = tz->tzp;
+ tz_id = tz->id;
+
+ 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_free(&thermal_tz_ida, tz->id);
+ ida_destroy(&tz->ida);
+ mutex_destroy(&tz->lock);
+ device_unregister(&tz->device);
+
+ thermal_notify_tz_delete(tz_id);
+}
+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;
+
+ 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) {
+ 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;
+
+ result = thermal_netlink_init();
+ if (result)
+ goto error;
+
+ result = thermal_register_governors();
+ if (result)
+ goto error;
+
+ result = class_register(&thermal_class);
+ if (result)
+ goto unregister_governors;
+
+ result = register_pm_notifier(&thermal_pm_nb);
+ if (result)
+ pr_warn("Thermal: Can not register suspend notifier, return %d\n",
+ result);
+
+ return 0;
+
+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);
+ return result;
+}
+postcore_initcall(thermal_init);