OpenCloudOS-Kernel/drivers/acpi/thermal.c

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/*
* acpi_thermal.c - ACPI Thermal Zone Driver ($Revision: 41 $)
*
* Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
* Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@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; either version 2 of the License, or (at
* your option) any later version.
*
* 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.
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* This driver fully implements the ACPI thermal policy as described in the
* ACPI 2.0 Specification.
*
* TBD: 1. Implement passive cooling hysteresis.
* 2. Enhance passive cooling (CPU) states/limit interface to support
* concepts of 'multiple limiters', upper/lower limits, etc.
*
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/dmi.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/proc_fs.h>
#include <linux/jiffies.h>
#include <linux/kmod.h>
#include <linux/seq_file.h>
#include <linux/reboot.h>
#include <linux/device.h>
#include <asm/uaccess.h>
#include <linux/thermal.h>
#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>
#define PREFIX "ACPI: "
#define ACPI_THERMAL_CLASS "thermal_zone"
#define ACPI_THERMAL_DEVICE_NAME "Thermal Zone"
#define ACPI_THERMAL_FILE_STATE "state"
#define ACPI_THERMAL_FILE_TEMPERATURE "temperature"
#define ACPI_THERMAL_FILE_TRIP_POINTS "trip_points"
#define ACPI_THERMAL_FILE_COOLING_MODE "cooling_mode"
#define ACPI_THERMAL_FILE_POLLING_FREQ "polling_frequency"
#define ACPI_THERMAL_NOTIFY_TEMPERATURE 0x80
#define ACPI_THERMAL_NOTIFY_THRESHOLDS 0x81
#define ACPI_THERMAL_NOTIFY_DEVICES 0x82
#define ACPI_THERMAL_NOTIFY_CRITICAL 0xF0
#define ACPI_THERMAL_NOTIFY_HOT 0xF1
#define ACPI_THERMAL_MODE_ACTIVE 0x00
#define ACPI_THERMAL_MAX_ACTIVE 10
#define ACPI_THERMAL_MAX_LIMIT_STR_LEN 65
#define _COMPONENT ACPI_THERMAL_COMPONENT
ACPI_MODULE_NAME("thermal");
MODULE_AUTHOR("Paul Diefenbaugh");
MODULE_DESCRIPTION("ACPI Thermal Zone Driver");
MODULE_LICENSE("GPL");
static int act;
module_param(act, int, 0644);
MODULE_PARM_DESC(act, "Disable or override all lowest active trip points.");
static int crt;
module_param(crt, int, 0644);
MODULE_PARM_DESC(crt, "Disable or lower all critical trip points.");
static int tzp;
ACPI: thermal: expose "thermal.tzp=" to set global polling frequency Thermal Zone Polling frequency (_TZP) is an optional ACPI object recommending the rate that the OS should poll the associated thermal zone. If _TZP is 0, no polling should be used. If _TZP is non-zero, then the platform recommends that the OS poll the thermal zone at the specified rate. The minimum period is 30 seconds. The maximum period is 5 minutes. (note _TZP and thermal.tzp units are in deci-seconds, so _TZP = 300 corresponds to 30 seconds) If _TZP is not present, ACPI 3.0b recommends that the thermal zone be polled at an "OS provided default frequency". However, common industry practice is: 1. The BIOS never specifies any _TZP 2. High volume OS's from this century never poll any thermal zones Ie. The OS depends on the platform's ability to provoke thermal events when necessary, and the "OS provided default frequency" is "never":-) There is a proposal that ACPI 4.0 be updated to reflect common industry practice -- ie. no _TZP, no polling. The Linux kernel already follows this practice -- thermal zones are not polled unless _TZP is present and non-zero. But thermal zone polling is useful as a workaround for systems which have ACPI thermal control, but have an issue preventing thermal events. Indeed, some Linux distributions still set a non-zero thermal polling frequency for this reason. But rather than ask the user to write a polling frequency into all the /proc/acpi/thermal_zone/*/polling_frequency files, here we simply document and expose the already existing module parameter to do the same at system level, to simplify debugging those broken platforms. Note that thermal.tzp is a module-load time parameter only. Signed-off-by: Len Brown <len.brown@intel.com>
2007-08-12 12:12:26 +08:00
module_param(tzp, int, 0444);
MODULE_PARM_DESC(tzp, "Thermal zone polling frequency, in 1/10 seconds.");
static int nocrt;
module_param(nocrt, int, 0);
MODULE_PARM_DESC(nocrt, "Set to take no action upon ACPI thermal zone critical trips points.");
static int off;
module_param(off, int, 0);
MODULE_PARM_DESC(off, "Set to disable ACPI thermal support.");
static int psv;
module_param(psv, int, 0644);
MODULE_PARM_DESC(psv, "Disable or override all passive trip points.");
static int acpi_thermal_add(struct acpi_device *device);
static int acpi_thermal_remove(struct acpi_device *device, int type);
static int acpi_thermal_resume(struct acpi_device *device);
static void acpi_thermal_notify(struct acpi_device *device, u32 event);
static int acpi_thermal_state_open_fs(struct inode *inode, struct file *file);
static int acpi_thermal_temp_open_fs(struct inode *inode, struct file *file);
static int acpi_thermal_trip_open_fs(struct inode *inode, struct file *file);
static int acpi_thermal_cooling_open_fs(struct inode *inode, struct file *file);
static ssize_t acpi_thermal_write_cooling_mode(struct file *,
const char __user *, size_t,
loff_t *);
static int acpi_thermal_polling_open_fs(struct inode *inode, struct file *file);
static ssize_t acpi_thermal_write_polling(struct file *, const char __user *,
size_t, loff_t *);
static const struct acpi_device_id thermal_device_ids[] = {
{ACPI_THERMAL_HID, 0},
{"", 0},
};
MODULE_DEVICE_TABLE(acpi, thermal_device_ids);
static struct acpi_driver acpi_thermal_driver = {
.name = "thermal",
.class = ACPI_THERMAL_CLASS,
.ids = thermal_device_ids,
.ops = {
.add = acpi_thermal_add,
.remove = acpi_thermal_remove,
.resume = acpi_thermal_resume,
.notify = acpi_thermal_notify,
},
};
struct acpi_thermal_state {
u8 critical:1;
u8 hot:1;
u8 passive:1;
u8 active:1;
u8 reserved:4;
int active_index;
};
struct acpi_thermal_state_flags {
u8 valid:1;
u8 enabled:1;
u8 reserved:6;
};
struct acpi_thermal_critical {
struct acpi_thermal_state_flags flags;
unsigned long temperature;
};
struct acpi_thermal_hot {
struct acpi_thermal_state_flags flags;
unsigned long temperature;
};
struct acpi_thermal_passive {
struct acpi_thermal_state_flags flags;
unsigned long temperature;
unsigned long tc1;
unsigned long tc2;
unsigned long tsp;
struct acpi_handle_list devices;
};
struct acpi_thermal_active {
struct acpi_thermal_state_flags flags;
unsigned long temperature;
struct acpi_handle_list devices;
};
struct acpi_thermal_trips {
struct acpi_thermal_critical critical;
struct acpi_thermal_hot hot;
struct acpi_thermal_passive passive;
struct acpi_thermal_active active[ACPI_THERMAL_MAX_ACTIVE];
};
struct acpi_thermal_flags {
u8 cooling_mode:1; /* _SCP */
u8 devices:1; /* _TZD */
u8 reserved:6;
};
struct acpi_thermal {
struct acpi_device * device;
acpi_bus_id name;
unsigned long temperature;
unsigned long last_temperature;
unsigned long polling_frequency;
volatile u8 zombie;
struct acpi_thermal_flags flags;
struct acpi_thermal_state state;
struct acpi_thermal_trips trips;
struct acpi_handle_list devices;
struct thermal_zone_device *thermal_zone;
int tz_enabled;
int kelvin_offset;
struct mutex lock;
};
static const struct file_operations acpi_thermal_state_fops = {
.owner = THIS_MODULE,
.open = acpi_thermal_state_open_fs,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static const struct file_operations acpi_thermal_temp_fops = {
.owner = THIS_MODULE,
.open = acpi_thermal_temp_open_fs,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static const struct file_operations acpi_thermal_trip_fops = {
.owner = THIS_MODULE,
.open = acpi_thermal_trip_open_fs,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static const struct file_operations acpi_thermal_cooling_fops = {
.owner = THIS_MODULE,
.open = acpi_thermal_cooling_open_fs,
.read = seq_read,
.write = acpi_thermal_write_cooling_mode,
.llseek = seq_lseek,
.release = single_release,
};
static const struct file_operations acpi_thermal_polling_fops = {
.owner = THIS_MODULE,
.open = acpi_thermal_polling_open_fs,
.read = seq_read,
.write = acpi_thermal_write_polling,
.llseek = seq_lseek,
.release = single_release,
};
/* --------------------------------------------------------------------------
Thermal Zone Management
-------------------------------------------------------------------------- */
static int acpi_thermal_get_temperature(struct acpi_thermal *tz)
{
acpi_status status = AE_OK;
unsigned long long tmp;
if (!tz)
return -EINVAL;
tz->last_temperature = tz->temperature;
status = acpi_evaluate_integer(tz->device->handle, "_TMP", NULL, &tmp);
if (ACPI_FAILURE(status))
return -ENODEV;
tz->temperature = tmp;
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Temperature is %lu dK\n",
tz->temperature));
return 0;
}
static int acpi_thermal_get_polling_frequency(struct acpi_thermal *tz)
{
acpi_status status = AE_OK;
unsigned long long tmp;
if (!tz)
return -EINVAL;
status = acpi_evaluate_integer(tz->device->handle, "_TZP", NULL, &tmp);
if (ACPI_FAILURE(status))
return -ENODEV;
tz->polling_frequency = tmp;
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Polling frequency is %lu dS\n",
tz->polling_frequency));
return 0;
}
static int acpi_thermal_set_polling(struct acpi_thermal *tz, int seconds)
{
if (!tz)
return -EINVAL;
tz->polling_frequency = seconds * 10; /* Convert value to deci-seconds */
tz->thermal_zone->polling_delay = seconds * 1000;
if (tz->tz_enabled)
thermal_zone_device_update(tz->thermal_zone);
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Polling frequency set to %lu seconds\n",
tz->polling_frequency/10));
return 0;
}
static int acpi_thermal_set_cooling_mode(struct acpi_thermal *tz, int mode)
{
acpi_status status = AE_OK;
union acpi_object arg0 = { ACPI_TYPE_INTEGER };
struct acpi_object_list arg_list = { 1, &arg0 };
acpi_handle handle = NULL;
if (!tz)
return -EINVAL;
status = acpi_get_handle(tz->device->handle, "_SCP", &handle);
if (ACPI_FAILURE(status)) {
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "_SCP not present\n"));
return -ENODEV;
}
arg0.integer.value = mode;
status = acpi_evaluate_object(handle, NULL, &arg_list, NULL);
if (ACPI_FAILURE(status))
return -ENODEV;
return 0;
}
#define ACPI_TRIPS_CRITICAL 0x01
#define ACPI_TRIPS_HOT 0x02
#define ACPI_TRIPS_PASSIVE 0x04
#define ACPI_TRIPS_ACTIVE 0x08
#define ACPI_TRIPS_DEVICES 0x10
#define ACPI_TRIPS_REFRESH_THRESHOLDS (ACPI_TRIPS_PASSIVE | ACPI_TRIPS_ACTIVE)
#define ACPI_TRIPS_REFRESH_DEVICES ACPI_TRIPS_DEVICES
#define ACPI_TRIPS_INIT (ACPI_TRIPS_CRITICAL | ACPI_TRIPS_HOT | \
ACPI_TRIPS_PASSIVE | ACPI_TRIPS_ACTIVE | \
ACPI_TRIPS_DEVICES)
/*
* This exception is thrown out in two cases:
* 1.An invalid trip point becomes invalid or a valid trip point becomes invalid
* when re-evaluating the AML code.
* 2.TODO: Devices listed in _PSL, _ALx, _TZD may change.
* We need to re-bind the cooling devices of a thermal zone when this occurs.
*/
#define ACPI_THERMAL_TRIPS_EXCEPTION(flags, str) \
do { \
if (flags != ACPI_TRIPS_INIT) \
ACPI_EXCEPTION((AE_INFO, AE_ERROR, \
"ACPI thermal trip point %s changed\n" \
"Please send acpidump to linux-acpi@vger.kernel.org\n", str)); \
} while (0)
static int acpi_thermal_trips_update(struct acpi_thermal *tz, int flag)
{
acpi_status status = AE_OK;
unsigned long long tmp;
struct acpi_handle_list devices;
int valid = 0;
int i;
/* Critical Shutdown */
if (flag & ACPI_TRIPS_CRITICAL) {
status = acpi_evaluate_integer(tz->device->handle,
"_CRT", NULL, &tmp);
tz->trips.critical.temperature = tmp;
/*
* Treat freezing temperatures as invalid as well; some
* BIOSes return really low values and cause reboots at startup.
* Below zero (Celsius) values clearly aren't right for sure..
* ... so lets discard those as invalid.
*/
if (ACPI_FAILURE(status)) {
tz->trips.critical.flags.valid = 0;
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"No critical threshold\n"));
} else if (tmp <= 2732) {
printk(KERN_WARNING FW_BUG "Invalid critical threshold "
"(%llu)\n", tmp);
tz->trips.critical.flags.valid = 0;
} else {
tz->trips.critical.flags.valid = 1;
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Found critical threshold [%lu]\n",
tz->trips.critical.temperature));
}
if (tz->trips.critical.flags.valid == 1) {
if (crt == -1) {
tz->trips.critical.flags.valid = 0;
} else if (crt > 0) {
unsigned long crt_k = CELSIUS_TO_KELVIN(crt);
/*
* Allow override critical threshold
*/
if (crt_k > tz->trips.critical.temperature)
printk(KERN_WARNING PREFIX
"Critical threshold %d C\n", crt);
tz->trips.critical.temperature = crt_k;
}
}
}
/* Critical Sleep (optional) */
if (flag & ACPI_TRIPS_HOT) {
status = acpi_evaluate_integer(tz->device->handle,
"_HOT", NULL, &tmp);
if (ACPI_FAILURE(status)) {
tz->trips.hot.flags.valid = 0;
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"No hot threshold\n"));
} else {
tz->trips.hot.temperature = tmp;
tz->trips.hot.flags.valid = 1;
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Found hot threshold [%lu]\n",
tz->trips.critical.temperature));
}
}
/* Passive (optional) */
if (((flag & ACPI_TRIPS_PASSIVE) && tz->trips.passive.flags.valid) ||
(flag == ACPI_TRIPS_INIT)) {
valid = tz->trips.passive.flags.valid;
if (psv == -1) {
status = AE_SUPPORT;
} else if (psv > 0) {
tmp = CELSIUS_TO_KELVIN(psv);
status = AE_OK;
} else {
status = acpi_evaluate_integer(tz->device->handle,
"_PSV", NULL, &tmp);
}
if (ACPI_FAILURE(status))
tz->trips.passive.flags.valid = 0;
else {
tz->trips.passive.temperature = tmp;
tz->trips.passive.flags.valid = 1;
if (flag == ACPI_TRIPS_INIT) {
status = acpi_evaluate_integer(
tz->device->handle, "_TC1",
NULL, &tmp);
if (ACPI_FAILURE(status))
tz->trips.passive.flags.valid = 0;
else
tz->trips.passive.tc1 = tmp;
status = acpi_evaluate_integer(
tz->device->handle, "_TC2",
NULL, &tmp);
if (ACPI_FAILURE(status))
tz->trips.passive.flags.valid = 0;
else
tz->trips.passive.tc2 = tmp;
status = acpi_evaluate_integer(
tz->device->handle, "_TSP",
NULL, &tmp);
if (ACPI_FAILURE(status))
tz->trips.passive.flags.valid = 0;
else
tz->trips.passive.tsp = tmp;
}
}
}
if ((flag & ACPI_TRIPS_DEVICES) && tz->trips.passive.flags.valid) {
memset(&devices, 0, sizeof(struct acpi_handle_list));
status = acpi_evaluate_reference(tz->device->handle, "_PSL",
NULL, &devices);
if (ACPI_FAILURE(status)) {
printk(KERN_WARNING PREFIX
"Invalid passive threshold\n");
tz->trips.passive.flags.valid = 0;
}
else
tz->trips.passive.flags.valid = 1;
if (memcmp(&tz->trips.passive.devices, &devices,
sizeof(struct acpi_handle_list))) {
memcpy(&tz->trips.passive.devices, &devices,
sizeof(struct acpi_handle_list));
ACPI_THERMAL_TRIPS_EXCEPTION(flag, "device");
}
}
if ((flag & ACPI_TRIPS_PASSIVE) || (flag & ACPI_TRIPS_DEVICES)) {
if (valid != tz->trips.passive.flags.valid)
ACPI_THERMAL_TRIPS_EXCEPTION(flag, "state");
}
/* Active (optional) */
for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
char name[5] = { '_', 'A', 'C', ('0' + i), '\0' };
valid = tz->trips.active[i].flags.valid;
if (act == -1)
break; /* disable all active trip points */
if ((flag == ACPI_TRIPS_INIT) || ((flag & ACPI_TRIPS_ACTIVE) &&
tz->trips.active[i].flags.valid)) {
status = acpi_evaluate_integer(tz->device->handle,
name, NULL, &tmp);
if (ACPI_FAILURE(status)) {
tz->trips.active[i].flags.valid = 0;
if (i == 0)
break;
if (act <= 0)
break;
if (i == 1)
tz->trips.active[0].temperature =
CELSIUS_TO_KELVIN(act);
else
/*
* Don't allow override higher than
* the next higher trip point
*/
tz->trips.active[i - 1].temperature =
(tz->trips.active[i - 2].temperature <
CELSIUS_TO_KELVIN(act) ?
tz->trips.active[i - 2].temperature :
CELSIUS_TO_KELVIN(act));
break;
} else {
tz->trips.active[i].temperature = tmp;
tz->trips.active[i].flags.valid = 1;
}
}
name[2] = 'L';
if ((flag & ACPI_TRIPS_DEVICES) && tz->trips.active[i].flags.valid ) {
memset(&devices, 0, sizeof(struct acpi_handle_list));
status = acpi_evaluate_reference(tz->device->handle,
name, NULL, &devices);
if (ACPI_FAILURE(status)) {
printk(KERN_WARNING PREFIX
"Invalid active%d threshold\n", i);
tz->trips.active[i].flags.valid = 0;
}
else
tz->trips.active[i].flags.valid = 1;
if (memcmp(&tz->trips.active[i].devices, &devices,
sizeof(struct acpi_handle_list))) {
memcpy(&tz->trips.active[i].devices, &devices,
sizeof(struct acpi_handle_list));
ACPI_THERMAL_TRIPS_EXCEPTION(flag, "device");
}
}
if ((flag & ACPI_TRIPS_ACTIVE) || (flag & ACPI_TRIPS_DEVICES))
if (valid != tz->trips.active[i].flags.valid)
ACPI_THERMAL_TRIPS_EXCEPTION(flag, "state");
if (!tz->trips.active[i].flags.valid)
break;
}
if (flag & ACPI_TRIPS_DEVICES) {
memset(&devices, 0, sizeof(struct acpi_handle_list));
status = acpi_evaluate_reference(tz->device->handle, "_TZD",
NULL, &devices);
if (memcmp(&tz->devices, &devices,
sizeof(struct acpi_handle_list))) {
memcpy(&tz->devices, &devices,
sizeof(struct acpi_handle_list));
ACPI_THERMAL_TRIPS_EXCEPTION(flag, "device");
}
}
return 0;
}
static int acpi_thermal_get_trip_points(struct acpi_thermal *tz)
{
int i, valid, ret = acpi_thermal_trips_update(tz, ACPI_TRIPS_INIT);
if (ret)
return ret;
valid = tz->trips.critical.flags.valid |
tz->trips.hot.flags.valid |
tz->trips.passive.flags.valid;
for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++)
valid |= tz->trips.active[i].flags.valid;
if (!valid) {
printk(KERN_WARNING FW_BUG "No valid trip found\n");
return -ENODEV;
}
return 0;
}
static void acpi_thermal_check(void *data)
{
struct acpi_thermal *tz = data;
thermal_zone_device_update(tz->thermal_zone);
}
/* sys I/F for generic thermal sysfs support */
#define KELVIN_TO_MILLICELSIUS(t, off) (((t) - (off)) * 100)
static int thermal_get_temp(struct thermal_zone_device *thermal,
unsigned long *temp)
{
struct acpi_thermal *tz = thermal->devdata;
int result;
if (!tz)
return -EINVAL;
result = acpi_thermal_get_temperature(tz);
if (result)
return result;
*temp = KELVIN_TO_MILLICELSIUS(tz->temperature, tz->kelvin_offset);
return 0;
}
static const char enabled[] = "kernel";
static const char disabled[] = "user";
static int thermal_get_mode(struct thermal_zone_device *thermal,
enum thermal_device_mode *mode)
{
struct acpi_thermal *tz = thermal->devdata;
if (!tz)
return -EINVAL;
*mode = tz->tz_enabled ? THERMAL_DEVICE_ENABLED :
THERMAL_DEVICE_DISABLED;
return 0;
}
static int thermal_set_mode(struct thermal_zone_device *thermal,
enum thermal_device_mode mode)
{
struct acpi_thermal *tz = thermal->devdata;
int enable;
if (!tz)
return -EINVAL;
/*
* enable/disable thermal management from ACPI thermal driver
*/
if (mode == THERMAL_DEVICE_ENABLED)
enable = 1;
else if (mode == THERMAL_DEVICE_DISABLED)
enable = 0;
else
return -EINVAL;
if (enable != tz->tz_enabled) {
tz->tz_enabled = enable;
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"%s ACPI thermal control\n",
tz->tz_enabled ? enabled : disabled));
acpi_thermal_check(tz);
}
return 0;
}
static int thermal_get_trip_type(struct thermal_zone_device *thermal,
int trip, enum thermal_trip_type *type)
{
struct acpi_thermal *tz = thermal->devdata;
int i;
if (!tz || trip < 0)
return -EINVAL;
if (tz->trips.critical.flags.valid) {
if (!trip) {
*type = THERMAL_TRIP_CRITICAL;
return 0;
}
trip--;
}
if (tz->trips.hot.flags.valid) {
if (!trip) {
*type = THERMAL_TRIP_HOT;
return 0;
}
trip--;
}
if (tz->trips.passive.flags.valid) {
if (!trip) {
*type = THERMAL_TRIP_PASSIVE;
return 0;
}
trip--;
}
for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
tz->trips.active[i].flags.valid; i++) {
if (!trip) {
*type = THERMAL_TRIP_ACTIVE;
return 0;
}
trip--;
}
return -EINVAL;
}
static int thermal_get_trip_temp(struct thermal_zone_device *thermal,
int trip, unsigned long *temp)
{
struct acpi_thermal *tz = thermal->devdata;
int i;
if (!tz || trip < 0)
return -EINVAL;
if (tz->trips.critical.flags.valid) {
if (!trip) {
*temp = KELVIN_TO_MILLICELSIUS(
tz->trips.critical.temperature,
tz->kelvin_offset);
return 0;
}
trip--;
}
if (tz->trips.hot.flags.valid) {
if (!trip) {
*temp = KELVIN_TO_MILLICELSIUS(
tz->trips.hot.temperature,
tz->kelvin_offset);
return 0;
}
trip--;
}
if (tz->trips.passive.flags.valid) {
if (!trip) {
*temp = KELVIN_TO_MILLICELSIUS(
tz->trips.passive.temperature,
tz->kelvin_offset);
return 0;
}
trip--;
}
for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
tz->trips.active[i].flags.valid; i++) {
if (!trip) {
*temp = KELVIN_TO_MILLICELSIUS(
tz->trips.active[i].temperature,
tz->kelvin_offset);
return 0;
}
trip--;
}
return -EINVAL;
}
static int thermal_get_crit_temp(struct thermal_zone_device *thermal,
unsigned long *temperature) {
struct acpi_thermal *tz = thermal->devdata;
if (tz->trips.critical.flags.valid) {
*temperature = KELVIN_TO_MILLICELSIUS(
tz->trips.critical.temperature,
tz->kelvin_offset);
return 0;
} else
return -EINVAL;
}
static int thermal_notify(struct thermal_zone_device *thermal, int trip,
enum thermal_trip_type trip_type)
{
u8 type = 0;
struct acpi_thermal *tz = thermal->devdata;
if (trip_type == THERMAL_TRIP_CRITICAL)
type = ACPI_THERMAL_NOTIFY_CRITICAL;
else if (trip_type == THERMAL_TRIP_HOT)
type = ACPI_THERMAL_NOTIFY_HOT;
else
return 0;
acpi_bus_generate_proc_event(tz->device, type, 1);
acpi_bus_generate_netlink_event(tz->device->pnp.device_class,
dev_name(&tz->device->dev), type, 1);
if (trip_type == THERMAL_TRIP_CRITICAL && nocrt)
return 1;
return 0;
}
typedef int (*cb)(struct thermal_zone_device *, int,
struct thermal_cooling_device *);
static int acpi_thermal_cooling_device_cb(struct thermal_zone_device *thermal,
struct thermal_cooling_device *cdev,
cb action)
{
struct acpi_device *device = cdev->devdata;
struct acpi_thermal *tz = thermal->devdata;
struct acpi_device *dev;
acpi_status status;
acpi_handle handle;
int i;
int j;
int trip = -1;
int result = 0;
if (tz->trips.critical.flags.valid)
trip++;
if (tz->trips.hot.flags.valid)
trip++;
if (tz->trips.passive.flags.valid) {
trip++;
for (i = 0; i < tz->trips.passive.devices.count;
i++) {
handle = tz->trips.passive.devices.handles[i];
status = acpi_bus_get_device(handle, &dev);
if (ACPI_SUCCESS(status) && (dev == device)) {
result = action(thermal, trip, cdev);
if (result)
goto failed;
}
}
}
for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
if (!tz->trips.active[i].flags.valid)
break;
trip++;
for (j = 0;
j < tz->trips.active[i].devices.count;
j++) {
handle = tz->trips.active[i].devices.handles[j];
status = acpi_bus_get_device(handle, &dev);
if (ACPI_SUCCESS(status) && (dev == device)) {
result = action(thermal, trip, cdev);
if (result)
goto failed;
}
}
}
for (i = 0; i < tz->devices.count; i++) {
handle = tz->devices.handles[i];
status = acpi_bus_get_device(handle, &dev);
if (ACPI_SUCCESS(status) && (dev == device)) {
result = action(thermal, -1, cdev);
if (result)
goto failed;
}
}
failed:
return result;
}
static int
acpi_thermal_bind_cooling_device(struct thermal_zone_device *thermal,
struct thermal_cooling_device *cdev)
{
return acpi_thermal_cooling_device_cb(thermal, cdev,
thermal_zone_bind_cooling_device);
}
static int
acpi_thermal_unbind_cooling_device(struct thermal_zone_device *thermal,
struct thermal_cooling_device *cdev)
{
return acpi_thermal_cooling_device_cb(thermal, cdev,
thermal_zone_unbind_cooling_device);
}
static struct thermal_zone_device_ops acpi_thermal_zone_ops = {
.bind = acpi_thermal_bind_cooling_device,
.unbind = acpi_thermal_unbind_cooling_device,
.get_temp = thermal_get_temp,
.get_mode = thermal_get_mode,
.set_mode = thermal_set_mode,
.get_trip_type = thermal_get_trip_type,
.get_trip_temp = thermal_get_trip_temp,
.get_crit_temp = thermal_get_crit_temp,
.notify = thermal_notify,
};
static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
{
int trips = 0;
int result;
acpi_status status;
int i;
if (tz->trips.critical.flags.valid)
trips++;
if (tz->trips.hot.flags.valid)
trips++;
if (tz->trips.passive.flags.valid)
trips++;
for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
tz->trips.active[i].flags.valid; i++, trips++);
if (tz->trips.passive.flags.valid)
tz->thermal_zone =
thermal_zone_device_register("acpitz", trips, tz,
&acpi_thermal_zone_ops,
tz->trips.passive.tc1,
tz->trips.passive.tc2,
tz->trips.passive.tsp*100,
tz->polling_frequency*100);
else
tz->thermal_zone =
thermal_zone_device_register("acpitz", trips, tz,
&acpi_thermal_zone_ops,
0, 0, 0,
tz->polling_frequency*100);
if (IS_ERR(tz->thermal_zone))
return -ENODEV;
result = sysfs_create_link(&tz->device->dev.kobj,
&tz->thermal_zone->device.kobj, "thermal_zone");
if (result)
return result;
result = sysfs_create_link(&tz->thermal_zone->device.kobj,
&tz->device->dev.kobj, "device");
if (result)
return result;
status = acpi_attach_data(tz->device->handle,
acpi_bus_private_data_handler,
tz->thermal_zone);
if (ACPI_FAILURE(status)) {
printk(KERN_ERR PREFIX
"Error attaching device data\n");
return -ENODEV;
}
tz->tz_enabled = 1;
dev_info(&tz->device->dev, "registered as thermal_zone%d\n",
tz->thermal_zone->id);
return 0;
}
static void acpi_thermal_unregister_thermal_zone(struct acpi_thermal *tz)
{
sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
sysfs_remove_link(&tz->thermal_zone->device.kobj, "device");
thermal_zone_device_unregister(tz->thermal_zone);
tz->thermal_zone = NULL;
acpi_detach_data(tz->device->handle, acpi_bus_private_data_handler);
}
/* --------------------------------------------------------------------------
FS Interface (/proc)
-------------------------------------------------------------------------- */
static struct proc_dir_entry *acpi_thermal_dir;
static int acpi_thermal_state_seq_show(struct seq_file *seq, void *offset)
{
struct acpi_thermal *tz = seq->private;
if (!tz)
goto end;
seq_puts(seq, "state: ");
if (!tz->state.critical && !tz->state.hot && !tz->state.passive
&& !tz->state.active)
seq_puts(seq, "ok\n");
else {
if (tz->state.critical)
seq_puts(seq, "critical ");
if (tz->state.hot)
seq_puts(seq, "hot ");
if (tz->state.passive)
seq_puts(seq, "passive ");
if (tz->state.active)
seq_printf(seq, "active[%d]", tz->state.active_index);
seq_puts(seq, "\n");
}
end:
return 0;
}
static int acpi_thermal_state_open_fs(struct inode *inode, struct file *file)
{
return single_open(file, acpi_thermal_state_seq_show, PDE(inode)->data);
}
static int acpi_thermal_temp_seq_show(struct seq_file *seq, void *offset)
{
int result = 0;
struct acpi_thermal *tz = seq->private;
if (!tz)
goto end;
result = acpi_thermal_get_temperature(tz);
if (result)
goto end;
seq_printf(seq, "temperature: %ld C\n",
KELVIN_TO_CELSIUS(tz->temperature));
end:
return 0;
}
static int acpi_thermal_temp_open_fs(struct inode *inode, struct file *file)
{
return single_open(file, acpi_thermal_temp_seq_show, PDE(inode)->data);
}
static int acpi_thermal_trip_seq_show(struct seq_file *seq, void *offset)
{
struct acpi_thermal *tz = seq->private;
struct acpi_device *device;
acpi_status status;
int i = 0;
int j = 0;
if (!tz)
goto end;
if (tz->trips.critical.flags.valid)
seq_printf(seq, "critical (S5): %ld C%s",
KELVIN_TO_CELSIUS(tz->trips.critical.temperature),
nocrt ? " <disabled>\n" : "\n");
if (tz->trips.hot.flags.valid)
seq_printf(seq, "hot (S4): %ld C%s",
KELVIN_TO_CELSIUS(tz->trips.hot.temperature),
nocrt ? " <disabled>\n" : "\n");
if (tz->trips.passive.flags.valid) {
seq_printf(seq,
"passive: %ld C: tc1=%lu tc2=%lu tsp=%lu devices=",
KELVIN_TO_CELSIUS(tz->trips.passive.temperature),
tz->trips.passive.tc1, tz->trips.passive.tc2,
tz->trips.passive.tsp);
for (j = 0; j < tz->trips.passive.devices.count; j++) {
status = acpi_bus_get_device(tz->trips.passive.devices.
handles[j], &device);
seq_printf(seq, "%4.4s ", status ? "" :
acpi_device_bid(device));
}
seq_puts(seq, "\n");
} else {
seq_printf(seq, "passive (forced):");
if (tz->thermal_zone->forced_passive)
seq_printf(seq, " %i C\n",
tz->thermal_zone->forced_passive / 1000);
else
seq_printf(seq, "<not set>\n");
}
for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
if (!(tz->trips.active[i].flags.valid))
break;
seq_printf(seq, "active[%d]: %ld C: devices=",
i,
KELVIN_TO_CELSIUS(tz->trips.active[i].temperature));
for (j = 0; j < tz->trips.active[i].devices.count; j++){
status = acpi_bus_get_device(tz->trips.active[i].
devices.handles[j],
&device);
seq_printf(seq, "%4.4s ", status ? "" :
acpi_device_bid(device));
}
seq_puts(seq, "\n");
}
end:
return 0;
}
static int acpi_thermal_trip_open_fs(struct inode *inode, struct file *file)
{
return single_open(file, acpi_thermal_trip_seq_show, PDE(inode)->data);
}
static int acpi_thermal_cooling_seq_show(struct seq_file *seq, void *offset)
{
struct acpi_thermal *tz = seq->private;
if (!tz)
goto end;
if (!tz->flags.cooling_mode)
seq_puts(seq, "<setting not supported>\n");
else
seq_puts(seq, "0 - Active; 1 - Passive\n");
end:
return 0;
}
static int acpi_thermal_cooling_open_fs(struct inode *inode, struct file *file)
{
return single_open(file, acpi_thermal_cooling_seq_show,
PDE(inode)->data);
}
static ssize_t
acpi_thermal_write_cooling_mode(struct file *file,
const char __user * buffer,
size_t count, loff_t * ppos)
{
struct seq_file *m = file->private_data;
struct acpi_thermal *tz = m->private;
int result = 0;
char mode_string[12] = { '\0' };
if (!tz || (count > sizeof(mode_string) - 1))
return -EINVAL;
if (!tz->flags.cooling_mode)
return -ENODEV;
if (copy_from_user(mode_string, buffer, count))
return -EFAULT;
mode_string[count] = '\0';
result = acpi_thermal_set_cooling_mode(tz,
simple_strtoul(mode_string, NULL,
0));
if (result)
return result;
acpi_thermal_check(tz);
return count;
}
static int acpi_thermal_polling_seq_show(struct seq_file *seq, void *offset)
{
struct acpi_thermal *tz = seq->private;
if (!tz)
goto end;
if (!tz->thermal_zone->polling_delay) {
seq_puts(seq, "<polling disabled>\n");
goto end;
}
seq_printf(seq, "polling frequency: %d seconds\n",
(tz->thermal_zone->polling_delay / 1000));
end:
return 0;
}
static int acpi_thermal_polling_open_fs(struct inode *inode, struct file *file)
{
return single_open(file, acpi_thermal_polling_seq_show,
PDE(inode)->data);
}
static ssize_t
acpi_thermal_write_polling(struct file *file,
const char __user * buffer,
size_t count, loff_t * ppos)
{
struct seq_file *m = file->private_data;
struct acpi_thermal *tz = m->private;
int result = 0;
char polling_string[12] = { '\0' };
int seconds = 0;
if (!tz || (count > sizeof(polling_string) - 1))
return -EINVAL;
if (copy_from_user(polling_string, buffer, count))
return -EFAULT;
polling_string[count] = '\0';
seconds = simple_strtoul(polling_string, NULL, 0);
result = acpi_thermal_set_polling(tz, seconds);
if (result)
return result;
acpi_thermal_check(tz);
return count;
}
static int acpi_thermal_add_fs(struct acpi_device *device)
{
struct proc_dir_entry *entry = NULL;
if (!acpi_device_dir(device)) {
acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
acpi_thermal_dir);
if (!acpi_device_dir(device))
return -ENODEV;
}
/* 'state' [R] */
entry = proc_create_data(ACPI_THERMAL_FILE_STATE,
S_IRUGO, acpi_device_dir(device),
&acpi_thermal_state_fops,
acpi_driver_data(device));
if (!entry)
return -ENODEV;
/* 'temperature' [R] */
entry = proc_create_data(ACPI_THERMAL_FILE_TEMPERATURE,
S_IRUGO, acpi_device_dir(device),
&acpi_thermal_temp_fops,
acpi_driver_data(device));
if (!entry)
return -ENODEV;
/* 'trip_points' [R] */
entry = proc_create_data(ACPI_THERMAL_FILE_TRIP_POINTS,
S_IRUGO,
acpi_device_dir(device),
&acpi_thermal_trip_fops,
acpi_driver_data(device));
if (!entry)
return -ENODEV;
/* 'cooling_mode' [R/W] */
entry = proc_create_data(ACPI_THERMAL_FILE_COOLING_MODE,
S_IFREG | S_IRUGO | S_IWUSR,
acpi_device_dir(device),
&acpi_thermal_cooling_fops,
acpi_driver_data(device));
if (!entry)
return -ENODEV;
/* 'polling_frequency' [R/W] */
entry = proc_create_data(ACPI_THERMAL_FILE_POLLING_FREQ,
S_IFREG | S_IRUGO | S_IWUSR,
acpi_device_dir(device),
&acpi_thermal_polling_fops,
acpi_driver_data(device));
if (!entry)
return -ENODEV;
return 0;
}
static int acpi_thermal_remove_fs(struct acpi_device *device)
{
if (acpi_device_dir(device)) {
remove_proc_entry(ACPI_THERMAL_FILE_POLLING_FREQ,
acpi_device_dir(device));
remove_proc_entry(ACPI_THERMAL_FILE_COOLING_MODE,
acpi_device_dir(device));
remove_proc_entry(ACPI_THERMAL_FILE_TRIP_POINTS,
acpi_device_dir(device));
remove_proc_entry(ACPI_THERMAL_FILE_TEMPERATURE,
acpi_device_dir(device));
remove_proc_entry(ACPI_THERMAL_FILE_STATE,
acpi_device_dir(device));
remove_proc_entry(acpi_device_bid(device), acpi_thermal_dir);
acpi_device_dir(device) = NULL;
}
return 0;
}
/* --------------------------------------------------------------------------
Driver Interface
-------------------------------------------------------------------------- */
static void acpi_thermal_notify(struct acpi_device *device, u32 event)
{
struct acpi_thermal *tz = acpi_driver_data(device);
if (!tz)
return;
switch (event) {
case ACPI_THERMAL_NOTIFY_TEMPERATURE:
acpi_thermal_check(tz);
break;
case ACPI_THERMAL_NOTIFY_THRESHOLDS:
acpi_thermal_trips_update(tz, ACPI_TRIPS_REFRESH_THRESHOLDS);
acpi_thermal_check(tz);
acpi_bus_generate_proc_event(device, event, 0);
acpi_bus_generate_netlink_event(device->pnp.device_class,
dev_name(&device->dev), event, 0);
break;
case ACPI_THERMAL_NOTIFY_DEVICES:
acpi_thermal_trips_update(tz, ACPI_TRIPS_REFRESH_DEVICES);
acpi_thermal_check(tz);
acpi_bus_generate_proc_event(device, event, 0);
acpi_bus_generate_netlink_event(device->pnp.device_class,
dev_name(&device->dev), event, 0);
break;
default:
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Unsupported event [0x%x]\n", event));
break;
}
}
static int acpi_thermal_get_info(struct acpi_thermal *tz)
{
int result = 0;
if (!tz)
return -EINVAL;
/* Get temperature [_TMP] (required) */
result = acpi_thermal_get_temperature(tz);
if (result)
return result;
/* Get trip points [_CRT, _PSV, etc.] (required) */
result = acpi_thermal_get_trip_points(tz);
if (result)
return result;
/* Set the cooling mode [_SCP] to active cooling (default) */
result = acpi_thermal_set_cooling_mode(tz, ACPI_THERMAL_MODE_ACTIVE);
if (!result)
tz->flags.cooling_mode = 1;
/* Get default polling frequency [_TZP] (optional) */
if (tzp)
tz->polling_frequency = tzp;
else
acpi_thermal_get_polling_frequency(tz);
return 0;
}
/*
* The exact offset between Kelvin and degree Celsius is 273.15. However ACPI
* handles temperature values with a single decimal place. As a consequence,
* some implementations use an offset of 273.1 and others use an offset of
* 273.2. Try to find out which one is being used, to present the most
* accurate and visually appealing number.
*
* The heuristic below should work for all ACPI thermal zones which have a
* critical trip point with a value being a multiple of 0.5 degree Celsius.
*/
static void acpi_thermal_guess_offset(struct acpi_thermal *tz)
{
if (tz->trips.critical.flags.valid &&
(tz->trips.critical.temperature % 5) == 1)
tz->kelvin_offset = 2731;
else
tz->kelvin_offset = 2732;
}
static int acpi_thermal_add(struct acpi_device *device)
{
int result = 0;
struct acpi_thermal *tz = NULL;
if (!device)
return -EINVAL;
tz = kzalloc(sizeof(struct acpi_thermal), GFP_KERNEL);
if (!tz)
return -ENOMEM;
tz->device = device;
strcpy(tz->name, device->pnp.bus_id);
strcpy(acpi_device_name(device), ACPI_THERMAL_DEVICE_NAME);
strcpy(acpi_device_class(device), ACPI_THERMAL_CLASS);
device->driver_data = tz;
mutex_init(&tz->lock);
result = acpi_thermal_get_info(tz);
if (result)
goto free_memory;
acpi_thermal_guess_offset(tz);
result = acpi_thermal_register_thermal_zone(tz);
if (result)
goto free_memory;
result = acpi_thermal_add_fs(device);
if (result)
goto unregister_thermal_zone;
printk(KERN_INFO PREFIX "%s [%s] (%ld C)\n",
acpi_device_name(device), acpi_device_bid(device),
KELVIN_TO_CELSIUS(tz->temperature));
goto end;
unregister_thermal_zone:
thermal_zone_device_unregister(tz->thermal_zone);
free_memory:
kfree(tz);
end:
return result;
}
static int acpi_thermal_remove(struct acpi_device *device, int type)
{
struct acpi_thermal *tz = NULL;
if (!device || !acpi_driver_data(device))
return -EINVAL;
tz = acpi_driver_data(device);
acpi_thermal_remove_fs(device);
acpi_thermal_unregister_thermal_zone(tz);
mutex_destroy(&tz->lock);
kfree(tz);
return 0;
}
static int acpi_thermal_resume(struct acpi_device *device)
{
struct acpi_thermal *tz = NULL;
int i, j, power_state, result;
if (!device || !acpi_driver_data(device))
return -EINVAL;
tz = acpi_driver_data(device);
for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
if (!(&tz->trips.active[i]))
break;
if (!tz->trips.active[i].flags.valid)
break;
tz->trips.active[i].flags.enabled = 1;
for (j = 0; j < tz->trips.active[i].devices.count; j++) {
result = acpi_bus_get_power(tz->trips.active[i].devices.
handles[j], &power_state);
if (result || (power_state != ACPI_STATE_D0)) {
tz->trips.active[i].flags.enabled = 0;
break;
}
}
tz->state.active |= tz->trips.active[i].flags.enabled;
}
acpi_thermal_check(tz);
return AE_OK;
}
static int thermal_act(const struct dmi_system_id *d) {
if (act == 0) {
printk(KERN_NOTICE "ACPI: %s detected: "
"disabling all active thermal trip points\n", d->ident);
act = -1;
}
return 0;
}
static int thermal_nocrt(const struct dmi_system_id *d) {
printk(KERN_NOTICE "ACPI: %s detected: "
"disabling all critical thermal trip point actions.\n", d->ident);
nocrt = 1;
return 0;
}
static int thermal_tzp(const struct dmi_system_id *d) {
if (tzp == 0) {
printk(KERN_NOTICE "ACPI: %s detected: "
"enabling thermal zone polling\n", d->ident);
tzp = 300; /* 300 dS = 30 Seconds */
}
return 0;
}
static int thermal_psv(const struct dmi_system_id *d) {
if (psv == 0) {
printk(KERN_NOTICE "ACPI: %s detected: "
"disabling all passive thermal trip points\n", d->ident);
psv = -1;
}
return 0;
}
static struct dmi_system_id thermal_dmi_table[] __initdata = {
/*
* Award BIOS on this AOpen makes thermal control almost worthless.
* http://bugzilla.kernel.org/show_bug.cgi?id=8842
*/
{
.callback = thermal_act,
.ident = "AOpen i915GMm-HFS",
.matches = {
DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
},
},
{
.callback = thermal_psv,
.ident = "AOpen i915GMm-HFS",
.matches = {
DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
},
},
{
.callback = thermal_tzp,
.ident = "AOpen i915GMm-HFS",
.matches = {
DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
},
},
{
.callback = thermal_nocrt,
.ident = "Gigabyte GA-7ZX",
.matches = {
DMI_MATCH(DMI_BOARD_VENDOR, "Gigabyte Technology Co., Ltd."),
DMI_MATCH(DMI_BOARD_NAME, "7ZX"),
},
},
{}
};
static int __init acpi_thermal_init(void)
{
int result = 0;
dmi_check_system(thermal_dmi_table);
if (off) {
printk(KERN_NOTICE "ACPI: thermal control disabled\n");
return -ENODEV;
}
acpi_thermal_dir = proc_mkdir(ACPI_THERMAL_CLASS, acpi_root_dir);
if (!acpi_thermal_dir)
return -ENODEV;
result = acpi_bus_register_driver(&acpi_thermal_driver);
if (result < 0) {
remove_proc_entry(ACPI_THERMAL_CLASS, acpi_root_dir);
return -ENODEV;
}
return 0;
}
static void __exit acpi_thermal_exit(void)
{
acpi_bus_unregister_driver(&acpi_thermal_driver);
remove_proc_entry(ACPI_THERMAL_CLASS, acpi_root_dir);
return;
}
module_init(acpi_thermal_init);
module_exit(acpi_thermal_exit);