text: /*
   *  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/slab.h>
  #include <linux/kdev_t.h>
  #include <linux/idr.h>
  #include <linux/thermal.h>
  #include <linux/spinlock.h>
  #include <linux/reboot.h>
  #include <net/netlink.h>
  #include <net/genetlink.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 unsigned int thermal_event_seqnum;
  
  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\n");
  	case THERMAL_TRIP_HOT:
  		return sprintf(buf, "hot\n");
  	case THERMAL_TRIP_PASSIVE:
  		return sprintf(buf, "passive\n");
  	case THERMAL_TRIP_ACTIVE:
  		return sprintf(buf, "active\n");
  	default:
  		return sprintf(buf, "unknown\n");
  	}
  }
  
  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;
  
  	/* sanity check: values below 1000 millicelcius don't make sense
  	 * and can cause the system to go into a thermal heart attack
  	 */
  	if (state && state < 1000)
  		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);
  		if (!tz->passive_delay)
  			tz->passive_delay = 1000;
  	} 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->passive_delay = 0;
  	}
  
  	tz->tc1 = 1;
  	tz->tc2 = 1;
  
  	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 ((long)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_get_drvdata(dev);
  	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;
  	}
  	dev_set_drvdata(hwmon->device, hwmon);
  	result = device_create_file(hwmon->device, &dev_attr_name);
  	if (result)
  		goto free_mem;
  
   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;
  	sysfs_attr_init(&tz->temp_input.attr.attr);
  	result = device_create_file(hwmon->device, &tz->temp_input.attr);
  	if (result)
  		goto unregister_name;
  
  	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;
  			sysfs_attr_init(&tz->temp_crit.attr.attr);
  			result = device_create_file(hwmon->device,
  						    &tz->temp_crit.attr);
  			if (result)
  				goto unregister_input;
  		}
  	}
  
  	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_input:
  	device_remove_file(hwmon->device, &tz->temp_input.attr);
   unregister_name:
  	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);
  	if (tz->ops->get_crit_temp)
  		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);
  	sysfs_attr_init(&dev->attr.attr);
  	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, const 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);
  
  	if (tz->ops->get_temp(tz, &temp)) {
  		/* get_temp failed - retry it later */
  		printk(KERN_WARNING PREFIX "failed to read out thermal zone "
  		       "%d\n", tz->id);
  		goto leave;
  	}
  
  	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;
  
        leave:
  	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);
  }
  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,
  	const 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);
  
  #ifdef CONFIG_NET
  static struct genl_family thermal_event_genl_family = {
  	.id = GENL_ID_GENERATE,
  	.name = THERMAL_GENL_FAMILY_NAME,
  	.version = THERMAL_GENL_VERSION,
  	.maxattr = THERMAL_GENL_ATTR_MAX,
  };
  
  static struct genl_multicast_group thermal_event_mcgrp = {
  	.name = THERMAL_GENL_MCAST_GROUP_NAME,
  };
  
  int generate_netlink_event(u32 orig, enum events event)
  {
  	struct sk_buff *skb;
  	struct nlattr *attr;
  	struct thermal_genl_event *thermal_event;
  	void *msg_header;
  	int size;
  	int result;
  
  	/* allocate memory */
  	size = nla_total_size(sizeof(struct thermal_genl_event)) + \
  				nla_total_size(0);
  
  	skb = genlmsg_new(size, GFP_ATOMIC);
  	if (!skb)
  		return -ENOMEM;
  
  	/* add the genetlink message header */
  	msg_header = genlmsg_put(skb, 0, thermal_event_seqnum++,
  				 &thermal_event_genl_family, 0,
  				 THERMAL_GENL_CMD_EVENT);
  	if (!msg_header) {
  		nlmsg_free(skb);
  		return -ENOMEM;
  	}
  
  	/* fill the data */
  	attr = nla_reserve(skb, THERMAL_GENL_ATTR_EVENT, \
  			sizeof(struct thermal_genl_event));
  
  	if (!attr) {
  		nlmsg_free(skb);
  		return -EINVAL;
  	}
  
  	thermal_event = nla_data(attr);
  	if (!thermal_event) {
  		nlmsg_free(skb);
  		return -EINVAL;
  	}
  
  	memset(thermal_event, 0, sizeof(struct thermal_genl_event));
  
  	thermal_event->orig = orig;
  	thermal_event->event = event;
  
  	/* send multicast genetlink message */
  	result = genlmsg_end(skb, msg_header);
  	if (result < 0) {
  		nlmsg_free(skb);
  		return result;
  	}
  
  	result = genlmsg_multicast(skb, 0, thermal_event_mcgrp.id, GFP_ATOMIC);
  	if (result)
  		printk(KERN_INFO "failed to send netlink event:%d", result);
  
  	return result;
  }
  EXPORT_SYMBOL(generate_netlink_event);
  
  static int genetlink_init(void)
  {
  	int result;
  
  	result = genl_register_family(&thermal_event_genl_family);
  	if (result)
  		return result;
  
  	result = genl_register_mc_group(&thermal_event_genl_family,
  					&thermal_event_mcgrp);
  	if (result)
  		genl_unregister_family(&thermal_event_genl_family);
  	return result;
  }
  
  static void genetlink_exit(void)
  {
  	genl_unregister_family(&thermal_event_genl_family);
  }
  #else /* !CONFIG_NET */
  static inline int genetlink_init(void) { return 0; }
  static inline void genetlink_exit(void) {}
  #endif /* !CONFIG_NET */
  
  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;
  	}
  	result = genetlink_init();
  	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);
  	genetlink_exit();
  }
  
  fs_initcall(thermal_init);
  module_exit(thermal_exit);
  