2 * A hwmon driver for ACPI 4.0 power meters
3 * Copyright (C) 2009 IBM
5 * Author: Darrick J. Wong <djwong@us.ibm.com>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 #include <linux/module.h>
23 #include <linux/hwmon.h>
24 #include <linux/hwmon-sysfs.h>
25 #include <linux/jiffies.h>
26 #include <linux/mutex.h>
27 #include <linux/dmi.h>
28 #include <linux/slab.h>
29 #include <linux/kdev_t.h>
30 #include <linux/sched.h>
31 #include <linux/time.h>
32 #include <acpi/acpi_drivers.h>
33 #include <acpi/acpi_bus.h>
35 #define ACPI_POWER_METER_NAME "power_meter"
36 ACPI_MODULE_NAME(ACPI_POWER_METER_NAME);
37 #define ACPI_POWER_METER_DEVICE_NAME "Power Meter"
38 #define ACPI_POWER_METER_CLASS "pwr_meter_resource"
40 #define NUM_SENSORS 17
42 #define POWER_METER_CAN_MEASURE (1 << 0)
43 #define POWER_METER_CAN_TRIP (1 << 1)
44 #define POWER_METER_CAN_CAP (1 << 2)
45 #define POWER_METER_CAN_NOTIFY (1 << 3)
46 #define POWER_METER_IS_BATTERY (1 << 8)
47 #define UNKNOWN_HYSTERESIS 0xFFFFFFFF
49 #define METER_NOTIFY_CONFIG 0x80
50 #define METER_NOTIFY_TRIP 0x81
51 #define METER_NOTIFY_CAP 0x82
52 #define METER_NOTIFY_CAPPING 0x83
53 #define METER_NOTIFY_INTERVAL 0x84
55 #define POWER_AVERAGE_NAME "power1_average"
56 #define POWER_CAP_NAME "power1_cap"
57 #define POWER_AVG_INTERVAL_NAME "power1_average_interval"
58 #define POWER_ALARM_NAME "power1_alarm"
60 static int cap_in_hardware;
61 static bool force_cap_on;
63 static int can_cap_in_hardware(void)
65 return force_cap_on || cap_in_hardware;
68 static const struct acpi_device_id power_meter_ids[] = {
72 MODULE_DEVICE_TABLE(acpi, power_meter_ids);
74 struct acpi_power_meter_capabilities {
88 struct acpi_power_meter_resource {
89 struct acpi_device *acpi_dev;
92 struct device *hwmon_dev;
93 struct acpi_power_meter_capabilities caps;
94 acpi_string model_number;
95 acpi_string serial_number;
101 unsigned long sensors_last_updated;
102 struct sensor_device_attribute sensors[NUM_SENSORS];
105 int num_domain_devices;
106 struct acpi_device **domain_devices;
107 struct kobject *holders_dir;
110 struct sensor_template {
112 ssize_t (*show)(struct device *dev,
113 struct device_attribute *devattr,
115 ssize_t (*set)(struct device *dev,
116 struct device_attribute *devattr,
117 const char *buf, size_t count);
121 /* Averaging interval */
122 static int update_avg_interval(struct acpi_power_meter_resource *resource)
124 unsigned long long data;
127 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_GAI",
129 if (ACPI_FAILURE(status)) {
130 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _GAI"));
134 resource->avg_interval = data;
138 static ssize_t show_avg_interval(struct device *dev,
139 struct device_attribute *devattr,
142 struct acpi_device *acpi_dev = to_acpi_device(dev);
143 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
145 mutex_lock(&resource->lock);
146 update_avg_interval(resource);
147 mutex_unlock(&resource->lock);
149 return sprintf(buf, "%llu\n", resource->avg_interval);
152 static ssize_t set_avg_interval(struct device *dev,
153 struct device_attribute *devattr,
154 const char *buf, size_t count)
156 struct acpi_device *acpi_dev = to_acpi_device(dev);
157 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
158 union acpi_object arg0 = { ACPI_TYPE_INTEGER };
159 struct acpi_object_list args = { 1, &arg0 };
162 unsigned long long data;
165 res = kstrtoul(buf, 10, &temp);
169 if (temp > resource->caps.max_avg_interval ||
170 temp < resource->caps.min_avg_interval)
172 arg0.integer.value = temp;
174 mutex_lock(&resource->lock);
175 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_PAI",
177 if (!ACPI_FAILURE(status))
178 resource->avg_interval = temp;
179 mutex_unlock(&resource->lock);
181 if (ACPI_FAILURE(status)) {
182 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PAI"));
186 /* _PAI returns 0 on success, nonzero otherwise */
194 static int update_cap(struct acpi_power_meter_resource *resource)
196 unsigned long long data;
199 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_GHL",
201 if (ACPI_FAILURE(status)) {
202 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _GHL"));
206 resource->cap = data;
210 static ssize_t show_cap(struct device *dev,
211 struct device_attribute *devattr,
214 struct acpi_device *acpi_dev = to_acpi_device(dev);
215 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
217 mutex_lock(&resource->lock);
218 update_cap(resource);
219 mutex_unlock(&resource->lock);
221 return sprintf(buf, "%llu\n", resource->cap * 1000);
224 static ssize_t set_cap(struct device *dev, struct device_attribute *devattr,
225 const char *buf, size_t count)
227 struct acpi_device *acpi_dev = to_acpi_device(dev);
228 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
229 union acpi_object arg0 = { ACPI_TYPE_INTEGER };
230 struct acpi_object_list args = { 1, &arg0 };
233 unsigned long long data;
236 res = kstrtoul(buf, 10, &temp);
241 if (temp > resource->caps.max_cap || temp < resource->caps.min_cap)
243 arg0.integer.value = temp;
245 mutex_lock(&resource->lock);
246 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_SHL",
248 if (!ACPI_FAILURE(status))
249 resource->cap = temp;
250 mutex_unlock(&resource->lock);
252 if (ACPI_FAILURE(status)) {
253 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _SHL"));
257 /* _SHL returns 0 on success, nonzero otherwise */
264 /* Power meter trip points */
265 static int set_acpi_trip(struct acpi_power_meter_resource *resource)
267 union acpi_object arg_objs[] = {
271 struct acpi_object_list args = { 2, arg_objs };
272 unsigned long long data;
275 /* Both trip levels must be set */
276 if (resource->trip[0] < 0 || resource->trip[1] < 0)
279 /* This driver stores min, max; ACPI wants max, min. */
280 arg_objs[0].integer.value = resource->trip[1];
281 arg_objs[1].integer.value = resource->trip[0];
283 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_PTP",
285 if (ACPI_FAILURE(status)) {
286 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTP"));
290 /* _PTP returns 0 on success, nonzero otherwise */
297 static ssize_t set_trip(struct device *dev, struct device_attribute *devattr,
298 const char *buf, size_t count)
300 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
301 struct acpi_device *acpi_dev = to_acpi_device(dev);
302 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
306 res = kstrtoul(buf, 10, &temp);
314 mutex_lock(&resource->lock);
315 resource->trip[attr->index - 7] = temp;
316 res = set_acpi_trip(resource);
317 mutex_unlock(&resource->lock);
326 static int update_meter(struct acpi_power_meter_resource *resource)
328 unsigned long long data;
330 unsigned long local_jiffies = jiffies;
332 if (time_before(local_jiffies, resource->sensors_last_updated +
333 msecs_to_jiffies(resource->caps.sampling_time)) &&
334 resource->sensors_valid)
337 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_PMM",
339 if (ACPI_FAILURE(status)) {
340 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PMM"));
344 resource->power = data;
345 resource->sensors_valid = 1;
346 resource->sensors_last_updated = jiffies;
350 static ssize_t show_power(struct device *dev,
351 struct device_attribute *devattr,
354 struct acpi_device *acpi_dev = to_acpi_device(dev);
355 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
357 mutex_lock(&resource->lock);
358 update_meter(resource);
359 mutex_unlock(&resource->lock);
361 return sprintf(buf, "%llu\n", resource->power * 1000);
365 static ssize_t show_str(struct device *dev,
366 struct device_attribute *devattr,
369 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
370 struct acpi_device *acpi_dev = to_acpi_device(dev);
371 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
374 switch (attr->index) {
376 val = resource->model_number;
379 val = resource->serial_number;
382 val = resource->oem_info;
389 return sprintf(buf, "%s\n", val);
392 static ssize_t show_val(struct device *dev,
393 struct device_attribute *devattr,
396 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
397 struct acpi_device *acpi_dev = to_acpi_device(dev);
398 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
401 switch (attr->index) {
403 val = resource->caps.min_avg_interval;
406 val = resource->caps.max_avg_interval;
409 val = resource->caps.min_cap * 1000;
412 val = resource->caps.max_cap * 1000;
415 if (resource->caps.hysteresis == UNKNOWN_HYSTERESIS)
416 return sprintf(buf, "unknown\n");
418 val = resource->caps.hysteresis * 1000;
421 if (resource->caps.flags & POWER_METER_IS_BATTERY)
427 if (resource->power > resource->cap)
434 if (resource->trip[attr->index - 7] < 0)
435 return sprintf(buf, "unknown\n");
437 val = resource->trip[attr->index - 7] * 1000;
443 return sprintf(buf, "%llu\n", val);
446 static ssize_t show_accuracy(struct device *dev,
447 struct device_attribute *devattr,
450 struct acpi_device *acpi_dev = to_acpi_device(dev);
451 struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
452 unsigned int acc = resource->caps.accuracy;
454 return sprintf(buf, "%u.%u%%\n", acc / 1000, acc % 1000);
457 static ssize_t show_name(struct device *dev,
458 struct device_attribute *devattr,
461 return sprintf(buf, "%s\n", ACPI_POWER_METER_NAME);
464 /* Sensor descriptions. If you add a sensor, update NUM_SENSORS above! */
465 static struct sensor_template meter_ro_attrs[] = {
467 .label = POWER_AVERAGE_NAME,
472 .label = "power1_accuracy",
473 .show = show_accuracy,
476 { .label = "power1_average_interval_min",
481 .label = "power1_average_interval_max",
486 .label = "power1_is_battery",
493 static struct sensor_template meter_rw_attrs[] = {
495 .label = POWER_AVG_INTERVAL_NAME,
496 .show = show_avg_interval,
497 .set = set_avg_interval,
503 static struct sensor_template misc_cap_attrs[] = {
505 .label = "power1_cap_min",
510 .label = "power1_cap_max",
515 .label = "power1_cap_hyst",
520 .label = POWER_ALARM_NAME,
527 static struct sensor_template ro_cap_attrs[] = {
529 .label = POWER_CAP_NAME,
536 static struct sensor_template rw_cap_attrs[] = {
538 .label = POWER_CAP_NAME,
546 static struct sensor_template trip_attrs[] = {
548 .label = "power1_average_min",
554 .label = "power1_average_max",
562 static struct sensor_template misc_attrs[] = {
569 .label = "power1_model_number",
574 .label = "power1_oem_info",
579 .label = "power1_serial_number",
586 /* Read power domain data */
587 static void remove_domain_devices(struct acpi_power_meter_resource *resource)
591 if (!resource->num_domain_devices)
594 for (i = 0; i < resource->num_domain_devices; i++) {
595 struct acpi_device *obj = resource->domain_devices[i];
599 sysfs_remove_link(resource->holders_dir,
600 kobject_name(&obj->dev.kobj));
601 put_device(&obj->dev);
604 kfree(resource->domain_devices);
605 kobject_put(resource->holders_dir);
606 resource->num_domain_devices = 0;
609 static int read_domain_devices(struct acpi_power_meter_resource *resource)
613 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
614 union acpi_object *pss;
617 status = acpi_evaluate_object(resource->acpi_dev->handle, "_PMD", NULL,
619 if (ACPI_FAILURE(status)) {
620 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PMD"));
624 pss = buffer.pointer;
626 pss->type != ACPI_TYPE_PACKAGE) {
627 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME
628 "Invalid _PMD data\n");
633 if (!pss->package.count)
636 resource->domain_devices = kzalloc(sizeof(struct acpi_device *) *
637 pss->package.count, GFP_KERNEL);
638 if (!resource->domain_devices) {
643 resource->holders_dir = kobject_create_and_add("measures",
644 &resource->acpi_dev->dev.kobj);
645 if (!resource->holders_dir) {
650 resource->num_domain_devices = pss->package.count;
652 for (i = 0; i < pss->package.count; i++) {
653 struct acpi_device *obj;
654 union acpi_object *element = &(pss->package.elements[i]);
656 /* Refuse non-references */
657 if (element->type != ACPI_TYPE_LOCAL_REFERENCE)
660 /* Create a symlink to domain objects */
661 resource->domain_devices[i] = NULL;
662 status = acpi_bus_get_device(element->reference.handle,
663 &resource->domain_devices[i]);
664 if (ACPI_FAILURE(status))
667 obj = resource->domain_devices[i];
668 get_device(&obj->dev);
670 res = sysfs_create_link(resource->holders_dir, &obj->dev.kobj,
671 kobject_name(&obj->dev.kobj));
673 put_device(&obj->dev);
674 resource->domain_devices[i] = NULL;
682 kfree(resource->domain_devices);
684 kfree(buffer.pointer);
688 /* Registration and deregistration */
689 static int register_ro_attrs(struct acpi_power_meter_resource *resource,
690 struct sensor_template *ro)
692 struct device *dev = &resource->acpi_dev->dev;
693 struct sensor_device_attribute *sensors =
694 &resource->sensors[resource->num_sensors];
698 sensors->dev_attr.attr.name = ro->label;
699 sensors->dev_attr.attr.mode = S_IRUGO;
700 sensors->dev_attr.show = ro->show;
701 sensors->index = ro->index;
703 sysfs_attr_init(&sensors->dev_attr.attr);
704 res = device_create_file(dev, &sensors->dev_attr);
706 sensors->dev_attr.attr.name = NULL;
710 resource->num_sensors++;
718 static int register_rw_attrs(struct acpi_power_meter_resource *resource,
719 struct sensor_template *rw)
721 struct device *dev = &resource->acpi_dev->dev;
722 struct sensor_device_attribute *sensors =
723 &resource->sensors[resource->num_sensors];
727 sensors->dev_attr.attr.name = rw->label;
728 sensors->dev_attr.attr.mode = S_IRUGO | S_IWUSR;
729 sensors->dev_attr.show = rw->show;
730 sensors->dev_attr.store = rw->set;
731 sensors->index = rw->index;
733 sysfs_attr_init(&sensors->dev_attr.attr);
734 res = device_create_file(dev, &sensors->dev_attr);
736 sensors->dev_attr.attr.name = NULL;
740 resource->num_sensors++;
748 static void remove_attrs(struct acpi_power_meter_resource *resource)
752 for (i = 0; i < resource->num_sensors; i++) {
753 if (!resource->sensors[i].dev_attr.attr.name)
755 device_remove_file(&resource->acpi_dev->dev,
756 &resource->sensors[i].dev_attr);
759 remove_domain_devices(resource);
761 resource->num_sensors = 0;
764 static int setup_attrs(struct acpi_power_meter_resource *resource)
768 res = read_domain_devices(resource);
772 if (resource->caps.flags & POWER_METER_CAN_MEASURE) {
773 res = register_ro_attrs(resource, meter_ro_attrs);
776 res = register_rw_attrs(resource, meter_rw_attrs);
781 if (resource->caps.flags & POWER_METER_CAN_CAP) {
782 if (!can_cap_in_hardware()) {
783 dev_err(&resource->acpi_dev->dev,
784 "Ignoring unsafe software power cap!\n");
785 goto skip_unsafe_cap;
788 if (resource->caps.configurable_cap) {
789 res = register_rw_attrs(resource, rw_cap_attrs);
793 res = register_ro_attrs(resource, ro_cap_attrs);
797 res = register_ro_attrs(resource, misc_cap_attrs);
803 if (resource->caps.flags & POWER_METER_CAN_TRIP) {
804 res = register_rw_attrs(resource, trip_attrs);
809 res = register_ro_attrs(resource, misc_attrs);
815 remove_attrs(resource);
819 static void free_capabilities(struct acpi_power_meter_resource *resource)
824 str = &resource->model_number;
825 for (i = 0; i < 3; i++, str++)
829 static int read_capabilities(struct acpi_power_meter_resource *resource)
833 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
834 struct acpi_buffer state = { 0, NULL };
835 struct acpi_buffer format = { sizeof("NNNNNNNNNNN"), "NNNNNNNNNNN" };
836 union acpi_object *pss;
840 status = acpi_evaluate_object(resource->acpi_dev->handle, "_PMC", NULL,
842 if (ACPI_FAILURE(status)) {
843 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PMC"));
847 pss = buffer.pointer;
849 pss->type != ACPI_TYPE_PACKAGE ||
850 pss->package.count != 14) {
851 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME
852 "Invalid _PMC data\n");
857 /* Grab all the integer data at once */
858 state.length = sizeof(struct acpi_power_meter_capabilities);
859 state.pointer = &resource->caps;
861 status = acpi_extract_package(pss, &format, &state);
862 if (ACPI_FAILURE(status)) {
863 ACPI_EXCEPTION((AE_INFO, status, "Invalid data"));
868 if (resource->caps.units) {
869 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME
870 "Unknown units %llu.\n",
871 resource->caps.units);
876 /* Grab the string data */
877 str = &resource->model_number;
879 for (i = 11; i < 14; i++) {
880 union acpi_object *element = &(pss->package.elements[i]);
882 if (element->type != ACPI_TYPE_STRING) {
887 *str = kzalloc(sizeof(u8) * (element->string.length + 1),
894 strncpy(*str, element->string.pointer, element->string.length);
898 dev_info(&resource->acpi_dev->dev, "Found ACPI power meter.\n");
901 str = &resource->model_number;
902 for (i = 0; i < 3; i++, str++)
905 kfree(buffer.pointer);
909 /* Handle ACPI event notifications */
910 static void acpi_power_meter_notify(struct acpi_device *device, u32 event)
912 struct acpi_power_meter_resource *resource;
915 if (!device || !acpi_driver_data(device))
918 resource = acpi_driver_data(device);
920 mutex_lock(&resource->lock);
922 case METER_NOTIFY_CONFIG:
923 free_capabilities(resource);
924 res = read_capabilities(resource);
928 remove_attrs(resource);
929 setup_attrs(resource);
931 case METER_NOTIFY_TRIP:
932 sysfs_notify(&device->dev.kobj, NULL, POWER_AVERAGE_NAME);
933 update_meter(resource);
935 case METER_NOTIFY_CAP:
936 sysfs_notify(&device->dev.kobj, NULL, POWER_CAP_NAME);
937 update_cap(resource);
939 case METER_NOTIFY_INTERVAL:
940 sysfs_notify(&device->dev.kobj, NULL, POWER_AVG_INTERVAL_NAME);
941 update_avg_interval(resource);
943 case METER_NOTIFY_CAPPING:
944 sysfs_notify(&device->dev.kobj, NULL, POWER_ALARM_NAME);
945 dev_info(&device->dev, "Capping in progress.\n");
950 mutex_unlock(&resource->lock);
952 acpi_bus_generate_netlink_event(ACPI_POWER_METER_CLASS,
953 dev_name(&device->dev), event, 0);
956 static int acpi_power_meter_add(struct acpi_device *device)
959 struct acpi_power_meter_resource *resource;
964 resource = kzalloc(sizeof(struct acpi_power_meter_resource),
969 resource->sensors_valid = 0;
970 resource->acpi_dev = device;
971 mutex_init(&resource->lock);
972 strcpy(acpi_device_name(device), ACPI_POWER_METER_DEVICE_NAME);
973 strcpy(acpi_device_class(device), ACPI_POWER_METER_CLASS);
974 device->driver_data = resource;
976 free_capabilities(resource);
977 res = read_capabilities(resource);
981 resource->trip[0] = resource->trip[1] = -1;
983 res = setup_attrs(resource);
987 resource->hwmon_dev = hwmon_device_register(&device->dev);
988 if (IS_ERR(resource->hwmon_dev)) {
989 res = PTR_ERR(resource->hwmon_dev);
997 remove_attrs(resource);
1004 static int acpi_power_meter_remove(struct acpi_device *device, int type)
1006 struct acpi_power_meter_resource *resource;
1008 if (!device || !acpi_driver_data(device))
1011 resource = acpi_driver_data(device);
1012 hwmon_device_unregister(resource->hwmon_dev);
1014 free_capabilities(resource);
1015 remove_attrs(resource);
1021 static int acpi_power_meter_resume(struct acpi_device *device)
1023 struct acpi_power_meter_resource *resource;
1025 if (!device || !acpi_driver_data(device))
1028 resource = acpi_driver_data(device);
1029 free_capabilities(resource);
1030 read_capabilities(resource);
1035 static struct acpi_driver acpi_power_meter_driver = {
1036 .name = "power_meter",
1037 .class = ACPI_POWER_METER_CLASS,
1038 .ids = power_meter_ids,
1040 .add = acpi_power_meter_add,
1041 .remove = acpi_power_meter_remove,
1042 .resume = acpi_power_meter_resume,
1043 .notify = acpi_power_meter_notify,
1047 /* Module init/exit routines */
1048 static int __init enable_cap_knobs(const struct dmi_system_id *d)
1050 cap_in_hardware = 1;
1054 static struct dmi_system_id __initdata pm_dmi_table[] = {
1056 enable_cap_knobs, "IBM Active Energy Manager",
1058 DMI_MATCH(DMI_SYS_VENDOR, "IBM")
1064 static int __init acpi_power_meter_init(void)
1071 dmi_check_system(pm_dmi_table);
1073 result = acpi_bus_register_driver(&acpi_power_meter_driver);
1080 static void __exit acpi_power_meter_exit(void)
1082 acpi_bus_unregister_driver(&acpi_power_meter_driver);
1085 MODULE_AUTHOR("Darrick J. Wong <djwong@us.ibm.com>");
1086 MODULE_DESCRIPTION("ACPI 4.0 power meter driver");
1087 MODULE_LICENSE("GPL");
1089 module_param(force_cap_on, bool, 0644);
1090 MODULE_PARM_DESC(force_cap_on, "Enable power cap even it is unsafe to do so.");
1092 module_init(acpi_power_meter_init);
1093 module_exit(acpi_power_meter_exit);