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1/*
2 * acpi_ac.c - ACPI AC Adapter Driver ($Revision: 27 $)
3 *
4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6 *
7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or (at
12 * your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License along
20 * with this program; if not, write to the Free Software Foundation, Inc.,
21 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
22 *
23 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
24 */
25
26#include <linux/kernel.h>
27#include <linux/module.h>
28#include <linux/slab.h>
29#include <linux/init.h>
30#include <linux/types.h>
31#ifdef CONFIG_ACPI_PROCFS_POWER
32#include <linux/proc_fs.h>
33#include <linux/seq_file.h>
34#endif
35#include <linux/power_supply.h>
36#include <acpi/acpi_bus.h>
37#include <acpi/acpi_drivers.h>
38
39#define PREFIX "ACPI: "
40
41#define ACPI_AC_CLASS "ac_adapter"
42#define ACPI_AC_DEVICE_NAME "AC Adapter"
43#define ACPI_AC_FILE_STATE "state"
44#define ACPI_AC_NOTIFY_STATUS 0x80
45#define ACPI_AC_STATUS_OFFLINE 0x00
46#define ACPI_AC_STATUS_ONLINE 0x01
47#define ACPI_AC_STATUS_UNKNOWN 0xFF
48
49#define _COMPONENT ACPI_AC_COMPONENT
50ACPI_MODULE_NAME("ac");
51
52MODULE_AUTHOR("Paul Diefenbaugh");
53MODULE_DESCRIPTION("ACPI AC Adapter Driver");
54MODULE_LICENSE("GPL");
55
56#ifdef CONFIG_ACPI_PROCFS_POWER
57extern struct proc_dir_entry *acpi_lock_ac_dir(void);
58extern void *acpi_unlock_ac_dir(struct proc_dir_entry *acpi_ac_dir);
59static int acpi_ac_open_fs(struct inode *inode, struct file *file);
60#endif
61
62static int acpi_ac_add(struct acpi_device *device);
63static int acpi_ac_remove(struct acpi_device *device, int type);
64static int acpi_ac_resume(struct acpi_device *device);
65static void acpi_ac_notify(struct acpi_device *device, u32 event);
66
67static const struct acpi_device_id ac_device_ids[] = {
68 {"ACPI0003", 0},
69 {"", 0},
70};
71MODULE_DEVICE_TABLE(acpi, ac_device_ids);
72
73static struct acpi_driver acpi_ac_driver = {
74 .name = "ac",
75 .class = ACPI_AC_CLASS,
76 .ids = ac_device_ids,
77 .flags = ACPI_DRIVER_ALL_NOTIFY_EVENTS,
78 .ops = {
79 .add = acpi_ac_add,
80 .remove = acpi_ac_remove,
81 .resume = acpi_ac_resume,
82 .notify = acpi_ac_notify,
83 },
84};
85
86struct acpi_ac {
87 struct power_supply charger;
88 struct acpi_device * device;
89 unsigned long long state;
90};
91
92#define to_acpi_ac(x) container_of(x, struct acpi_ac, charger)
93
94#ifdef CONFIG_ACPI_PROCFS_POWER
95static const struct file_operations acpi_ac_fops = {
96 .owner = THIS_MODULE,
97 .open = acpi_ac_open_fs,
98 .read = seq_read,
99 .llseek = seq_lseek,
100 .release = single_release,
101};
102#endif
103
104/* --------------------------------------------------------------------------
105 AC Adapter Management
106 -------------------------------------------------------------------------- */
107
108static int acpi_ac_get_state(struct acpi_ac *ac)
109{
110 acpi_status status = AE_OK;
111
112
113 if (!ac)
114 return -EINVAL;
115
116 status = acpi_evaluate_integer(ac->device->handle, "_PSR", NULL, &ac->state);
117 if (ACPI_FAILURE(status)) {
118 ACPI_EXCEPTION((AE_INFO, status, "Error reading AC Adapter state"));
119 ac->state = ACPI_AC_STATUS_UNKNOWN;
120 return -ENODEV;
121 }
122
123 return 0;
124}
125
126/* --------------------------------------------------------------------------
127 sysfs I/F
128 -------------------------------------------------------------------------- */
129static int get_ac_property(struct power_supply *psy,
130 enum power_supply_property psp,
131 union power_supply_propval *val)
132{
133 struct acpi_ac *ac = to_acpi_ac(psy);
134
135 if (!ac)
136 return -ENODEV;
137
138 if (acpi_ac_get_state(ac))
139 return -ENODEV;
140
141 switch (psp) {
142 case POWER_SUPPLY_PROP_ONLINE:
143 val->intval = ac->state;
144 break;
145 default:
146 return -EINVAL;
147 }
148 return 0;
149}
150
151static enum power_supply_property ac_props[] = {
152 POWER_SUPPLY_PROP_ONLINE,
153};
154
155#ifdef CONFIG_ACPI_PROCFS_POWER
156/* --------------------------------------------------------------------------
157 FS Interface (/proc)
158 -------------------------------------------------------------------------- */
159
160static struct proc_dir_entry *acpi_ac_dir;
161
162static int acpi_ac_seq_show(struct seq_file *seq, void *offset)
163{
164 struct acpi_ac *ac = seq->private;
165
166
167 if (!ac)
168 return 0;
169
170 if (acpi_ac_get_state(ac)) {
171 seq_puts(seq, "ERROR: Unable to read AC Adapter state\n");
172 return 0;
173 }
174
175 seq_puts(seq, "state: ");
176 switch (ac->state) {
177 case ACPI_AC_STATUS_OFFLINE:
178 seq_puts(seq, "off-line\n");
179 break;
180 case ACPI_AC_STATUS_ONLINE:
181 seq_puts(seq, "on-line\n");
182 break;
183 default:
184 seq_puts(seq, "unknown\n");
185 break;
186 }
187
188 return 0;
189}
190
191static int acpi_ac_open_fs(struct inode *inode, struct file *file)
192{
193 return single_open(file, acpi_ac_seq_show, PDE(inode)->data);
194}
195
196static int acpi_ac_add_fs(struct acpi_device *device)
197{
198 struct proc_dir_entry *entry = NULL;
199
200 printk(KERN_WARNING PREFIX "Deprecated procfs I/F for AC is loaded,"
201 " please retry with CONFIG_ACPI_PROCFS_POWER cleared\n");
202 if (!acpi_device_dir(device)) {
203 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
204 acpi_ac_dir);
205 if (!acpi_device_dir(device))
206 return -ENODEV;
207 }
208
209 /* 'state' [R] */
210 entry = proc_create_data(ACPI_AC_FILE_STATE,
211 S_IRUGO, acpi_device_dir(device),
212 &acpi_ac_fops, acpi_driver_data(device));
213 if (!entry)
214 return -ENODEV;
215 return 0;
216}
217
218static int acpi_ac_remove_fs(struct acpi_device *device)
219{
220
221 if (acpi_device_dir(device)) {
222 remove_proc_entry(ACPI_AC_FILE_STATE, acpi_device_dir(device));
223
224 remove_proc_entry(acpi_device_bid(device), acpi_ac_dir);
225 acpi_device_dir(device) = NULL;
226 }
227
228 return 0;
229}
230#endif
231
232/* --------------------------------------------------------------------------
233 Driver Model
234 -------------------------------------------------------------------------- */
235
236static void acpi_ac_notify(struct acpi_device *device, u32 event)
237{
238 struct acpi_ac *ac = acpi_driver_data(device);
239
240
241 if (!ac)
242 return;
243
244 switch (event) {
245 default:
246 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
247 "Unsupported event [0x%x]\n", event));
248 case ACPI_AC_NOTIFY_STATUS:
249 case ACPI_NOTIFY_BUS_CHECK:
250 case ACPI_NOTIFY_DEVICE_CHECK:
251 acpi_ac_get_state(ac);
252 acpi_bus_generate_proc_event(device, event, (u32) ac->state);
253 acpi_bus_generate_netlink_event(device->pnp.device_class,
254 dev_name(&device->dev), event,
255 (u32) ac->state);
256 acpi_notifier_call_chain(device, event, (u32) ac->state);
257 kobject_uevent(&ac->charger.dev->kobj, KOBJ_CHANGE);
258 }
259
260 return;
261}
262
263static int acpi_ac_add(struct acpi_device *device)
264{
265 int result = 0;
266 struct acpi_ac *ac = NULL;
267
268
269 if (!device)
270 return -EINVAL;
271
272 ac = kzalloc(sizeof(struct acpi_ac), GFP_KERNEL);
273 if (!ac)
274 return -ENOMEM;
275
276 ac->device = device;
277 strcpy(acpi_device_name(device), ACPI_AC_DEVICE_NAME);
278 strcpy(acpi_device_class(device), ACPI_AC_CLASS);
279 device->driver_data = ac;
280
281 result = acpi_ac_get_state(ac);
282 if (result)
283 goto end;
284
285#ifdef CONFIG_ACPI_PROCFS_POWER
286 result = acpi_ac_add_fs(device);
287#endif
288 if (result)
289 goto end;
290 ac->charger.name = acpi_device_bid(device);
291 ac->charger.type = POWER_SUPPLY_TYPE_MAINS;
292 ac->charger.properties = ac_props;
293 ac->charger.num_properties = ARRAY_SIZE(ac_props);
294 ac->charger.get_property = get_ac_property;
295 result = power_supply_register(&ac->device->dev, &ac->charger);
296 if (result)
297 goto end;
298
299 printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
300 acpi_device_name(device), acpi_device_bid(device),
301 ac->state ? "on-line" : "off-line");
302
303 end:
304 if (result) {
305#ifdef CONFIG_ACPI_PROCFS_POWER
306 acpi_ac_remove_fs(device);
307#endif
308 kfree(ac);
309 }
310
311 return result;
312}
313
314static int acpi_ac_resume(struct acpi_device *device)
315{
316 struct acpi_ac *ac;
317 unsigned old_state;
318 if (!device || !acpi_driver_data(device))
319 return -EINVAL;
320 ac = acpi_driver_data(device);
321 old_state = ac->state;
322 if (acpi_ac_get_state(ac))
323 return 0;
324 if (old_state != ac->state)
325 kobject_uevent(&ac->charger.dev->kobj, KOBJ_CHANGE);
326 return 0;
327}
328
329static int acpi_ac_remove(struct acpi_device *device, int type)
330{
331 struct acpi_ac *ac = NULL;
332
333
334 if (!device || !acpi_driver_data(device))
335 return -EINVAL;
336
337 ac = acpi_driver_data(device);
338
339 if (ac->charger.dev)
340 power_supply_unregister(&ac->charger);
341#ifdef CONFIG_ACPI_PROCFS_POWER
342 acpi_ac_remove_fs(device);
343#endif
344
345 kfree(ac);
346
347 return 0;
348}
349
350static int __init acpi_ac_init(void)
351{
352 int result;
353
354 if (acpi_disabled)
355 return -ENODEV;
356
357#ifdef CONFIG_ACPI_PROCFS_POWER
358 acpi_ac_dir = acpi_lock_ac_dir();
359 if (!acpi_ac_dir)
360 return -ENODEV;
361#endif
362
363 result = acpi_bus_register_driver(&acpi_ac_driver);
364 if (result < 0) {
365#ifdef CONFIG_ACPI_PROCFS_POWER
366 acpi_unlock_ac_dir(acpi_ac_dir);
367#endif
368 return -ENODEV;
369 }
370
371 return 0;
372}
373
374static void __exit acpi_ac_exit(void)
375{
376
377 acpi_bus_unregister_driver(&acpi_ac_driver);
378
379#ifdef CONFIG_ACPI_PROCFS_POWER
380 acpi_unlock_ac_dir(acpi_ac_dir);
381#endif
382
383 return;
384}
385
386module_init(acpi_ac_init);
387module_exit(acpi_ac_exit);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * acpi_ac.c - ACPI AC Adapter Driver (Revision: 27)
4 *
5 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
6 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7 */
8
9#define pr_fmt(fmt) "ACPI: AC: " fmt
10
11#include <linux/kernel.h>
12#include <linux/module.h>
13#include <linux/slab.h>
14#include <linux/init.h>
15#include <linux/types.h>
16#include <linux/dmi.h>
17#include <linux/delay.h>
18#include <linux/platform_device.h>
19#include <linux/power_supply.h>
20#include <linux/acpi.h>
21#include <acpi/battery.h>
22
23#define ACPI_AC_CLASS "ac_adapter"
24#define ACPI_AC_DEVICE_NAME "AC Adapter"
25#define ACPI_AC_FILE_STATE "state"
26#define ACPI_AC_NOTIFY_STATUS 0x80
27#define ACPI_AC_STATUS_OFFLINE 0x00
28#define ACPI_AC_STATUS_ONLINE 0x01
29#define ACPI_AC_STATUS_UNKNOWN 0xFF
30
31MODULE_AUTHOR("Paul Diefenbaugh");
32MODULE_DESCRIPTION("ACPI AC Adapter Driver");
33MODULE_LICENSE("GPL");
34
35
36static int acpi_ac_add(struct acpi_device *device);
37static int acpi_ac_remove(struct acpi_device *device);
38static void acpi_ac_notify(struct acpi_device *device, u32 event);
39
40struct acpi_ac_bl {
41 const char *hid;
42 int hrv;
43};
44
45static const struct acpi_device_id ac_device_ids[] = {
46 {"ACPI0003", 0},
47 {"", 0},
48};
49MODULE_DEVICE_TABLE(acpi, ac_device_ids);
50
51/* Lists of PMIC ACPI HIDs with an (often better) native charger driver */
52static const struct acpi_ac_bl acpi_ac_blacklist[] = {
53 { "INT33F4", -1 }, /* X-Powers AXP288 PMIC */
54 { "INT34D3", 3 }, /* Intel Cherrytrail Whiskey Cove PMIC */
55};
56
57#ifdef CONFIG_PM_SLEEP
58static int acpi_ac_resume(struct device *dev);
59#endif
60static SIMPLE_DEV_PM_OPS(acpi_ac_pm, NULL, acpi_ac_resume);
61
62static int ac_sleep_before_get_state_ms;
63static int ac_check_pmic = 1;
64
65static struct acpi_driver acpi_ac_driver = {
66 .name = "ac",
67 .class = ACPI_AC_CLASS,
68 .ids = ac_device_ids,
69 .flags = ACPI_DRIVER_ALL_NOTIFY_EVENTS,
70 .ops = {
71 .add = acpi_ac_add,
72 .remove = acpi_ac_remove,
73 .notify = acpi_ac_notify,
74 },
75 .drv.pm = &acpi_ac_pm,
76};
77
78struct acpi_ac {
79 struct power_supply *charger;
80 struct power_supply_desc charger_desc;
81 struct acpi_device *device;
82 unsigned long long state;
83 struct notifier_block battery_nb;
84};
85
86#define to_acpi_ac(x) power_supply_get_drvdata(x)
87
88/* AC Adapter Management */
89static int acpi_ac_get_state(struct acpi_ac *ac)
90{
91 acpi_status status = AE_OK;
92
93 if (!ac)
94 return -EINVAL;
95
96 status = acpi_evaluate_integer(ac->device->handle, "_PSR", NULL,
97 &ac->state);
98 if (ACPI_FAILURE(status)) {
99 acpi_handle_info(ac->device->handle,
100 "Error reading AC Adapter state: %s\n",
101 acpi_format_exception(status));
102 ac->state = ACPI_AC_STATUS_UNKNOWN;
103 return -ENODEV;
104 }
105
106 return 0;
107}
108
109/* sysfs I/F */
110static int get_ac_property(struct power_supply *psy,
111 enum power_supply_property psp,
112 union power_supply_propval *val)
113{
114 struct acpi_ac *ac = to_acpi_ac(psy);
115
116 if (!ac)
117 return -ENODEV;
118
119 if (acpi_ac_get_state(ac))
120 return -ENODEV;
121
122 switch (psp) {
123 case POWER_SUPPLY_PROP_ONLINE:
124 val->intval = ac->state;
125 break;
126 default:
127 return -EINVAL;
128 }
129 return 0;
130}
131
132static enum power_supply_property ac_props[] = {
133 POWER_SUPPLY_PROP_ONLINE,
134};
135
136/* Driver Model */
137static void acpi_ac_notify(struct acpi_device *device, u32 event)
138{
139 struct acpi_ac *ac = acpi_driver_data(device);
140
141 if (!ac)
142 return;
143
144 switch (event) {
145 default:
146 acpi_handle_debug(device->handle, "Unsupported event [0x%x]\n",
147 event);
148 fallthrough;
149 case ACPI_AC_NOTIFY_STATUS:
150 case ACPI_NOTIFY_BUS_CHECK:
151 case ACPI_NOTIFY_DEVICE_CHECK:
152 /*
153 * A buggy BIOS may notify AC first and then sleep for
154 * a specific time before doing actual operations in the
155 * EC event handler (_Qxx). This will cause the AC state
156 * reported by the ACPI event to be incorrect, so wait for a
157 * specific time for the EC event handler to make progress.
158 */
159 if (ac_sleep_before_get_state_ms > 0)
160 msleep(ac_sleep_before_get_state_ms);
161
162 acpi_ac_get_state(ac);
163 acpi_bus_generate_netlink_event(device->pnp.device_class,
164 dev_name(&device->dev), event,
165 (u32) ac->state);
166 acpi_notifier_call_chain(device, event, (u32) ac->state);
167 kobject_uevent(&ac->charger->dev.kobj, KOBJ_CHANGE);
168 }
169}
170
171static int acpi_ac_battery_notify(struct notifier_block *nb,
172 unsigned long action, void *data)
173{
174 struct acpi_ac *ac = container_of(nb, struct acpi_ac, battery_nb);
175 struct acpi_bus_event *event = (struct acpi_bus_event *)data;
176
177 /*
178 * On HP Pavilion dv6-6179er AC status notifications aren't triggered
179 * when adapter is plugged/unplugged. However, battery status
180 * notifications are triggered when battery starts charging or
181 * discharging. Re-reading AC status triggers lost AC notifications,
182 * if AC status has changed.
183 */
184 if (strcmp(event->device_class, ACPI_BATTERY_CLASS) == 0 &&
185 event->type == ACPI_BATTERY_NOTIFY_STATUS)
186 acpi_ac_get_state(ac);
187
188 return NOTIFY_OK;
189}
190
191static int __init thinkpad_e530_quirk(const struct dmi_system_id *d)
192{
193 ac_sleep_before_get_state_ms = 1000;
194 return 0;
195}
196
197static int __init ac_do_not_check_pmic_quirk(const struct dmi_system_id *d)
198{
199 ac_check_pmic = 0;
200 return 0;
201}
202
203/* Please keep this list alphabetically sorted */
204static const struct dmi_system_id ac_dmi_table[] __initconst = {
205 {
206 /* ECS EF20EA, AXP288 PMIC but uses separate fuel-gauge */
207 .callback = ac_do_not_check_pmic_quirk,
208 .matches = {
209 DMI_MATCH(DMI_PRODUCT_NAME, "EF20EA"),
210 },
211 },
212 {
213 /* Lenovo Ideapad Miix 320, AXP288 PMIC, separate fuel-gauge */
214 .callback = ac_do_not_check_pmic_quirk,
215 .matches = {
216 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
217 DMI_MATCH(DMI_PRODUCT_NAME, "80XF"),
218 DMI_MATCH(DMI_PRODUCT_VERSION, "Lenovo MIIX 320-10ICR"),
219 },
220 },
221 {
222 /* Lenovo Thinkpad e530, see comment in acpi_ac_notify() */
223 .callback = thinkpad_e530_quirk,
224 .matches = {
225 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
226 DMI_MATCH(DMI_PRODUCT_NAME, "32597CG"),
227 },
228 },
229 {},
230};
231
232static int acpi_ac_add(struct acpi_device *device)
233{
234 struct power_supply_config psy_cfg = {};
235 int result = 0;
236 struct acpi_ac *ac = NULL;
237
238
239 if (!device)
240 return -EINVAL;
241
242 ac = kzalloc(sizeof(struct acpi_ac), GFP_KERNEL);
243 if (!ac)
244 return -ENOMEM;
245
246 ac->device = device;
247 strcpy(acpi_device_name(device), ACPI_AC_DEVICE_NAME);
248 strcpy(acpi_device_class(device), ACPI_AC_CLASS);
249 device->driver_data = ac;
250
251 result = acpi_ac_get_state(ac);
252 if (result)
253 goto end;
254
255 psy_cfg.drv_data = ac;
256
257 ac->charger_desc.name = acpi_device_bid(device);
258 ac->charger_desc.type = POWER_SUPPLY_TYPE_MAINS;
259 ac->charger_desc.properties = ac_props;
260 ac->charger_desc.num_properties = ARRAY_SIZE(ac_props);
261 ac->charger_desc.get_property = get_ac_property;
262 ac->charger = power_supply_register(&ac->device->dev,
263 &ac->charger_desc, &psy_cfg);
264 if (IS_ERR(ac->charger)) {
265 result = PTR_ERR(ac->charger);
266 goto end;
267 }
268
269 pr_info("%s [%s] (%s)\n", acpi_device_name(device),
270 acpi_device_bid(device), ac->state ? "on-line" : "off-line");
271
272 ac->battery_nb.notifier_call = acpi_ac_battery_notify;
273 register_acpi_notifier(&ac->battery_nb);
274end:
275 if (result)
276 kfree(ac);
277
278 return result;
279}
280
281#ifdef CONFIG_PM_SLEEP
282static int acpi_ac_resume(struct device *dev)
283{
284 struct acpi_ac *ac;
285 unsigned int old_state;
286
287 if (!dev)
288 return -EINVAL;
289
290 ac = acpi_driver_data(to_acpi_device(dev));
291 if (!ac)
292 return -EINVAL;
293
294 old_state = ac->state;
295 if (acpi_ac_get_state(ac))
296 return 0;
297 if (old_state != ac->state)
298 kobject_uevent(&ac->charger->dev.kobj, KOBJ_CHANGE);
299 return 0;
300}
301#else
302#define acpi_ac_resume NULL
303#endif
304
305static int acpi_ac_remove(struct acpi_device *device)
306{
307 struct acpi_ac *ac = NULL;
308
309
310 if (!device || !acpi_driver_data(device))
311 return -EINVAL;
312
313 ac = acpi_driver_data(device);
314
315 power_supply_unregister(ac->charger);
316 unregister_acpi_notifier(&ac->battery_nb);
317
318 kfree(ac);
319
320 return 0;
321}
322
323static int __init acpi_ac_init(void)
324{
325 unsigned int i;
326 int result;
327
328 if (acpi_disabled)
329 return -ENODEV;
330
331 dmi_check_system(ac_dmi_table);
332
333 if (ac_check_pmic) {
334 for (i = 0; i < ARRAY_SIZE(acpi_ac_blacklist); i++)
335 if (acpi_dev_present(acpi_ac_blacklist[i].hid, "1",
336 acpi_ac_blacklist[i].hrv)) {
337 pr_info("found native %s PMIC, not loading\n",
338 acpi_ac_blacklist[i].hid);
339 return -ENODEV;
340 }
341 }
342
343 result = acpi_bus_register_driver(&acpi_ac_driver);
344 if (result < 0)
345 return -ENODEV;
346
347 return 0;
348}
349
350static void __exit acpi_ac_exit(void)
351{
352 acpi_bus_unregister_driver(&acpi_ac_driver);
353}
354module_init(acpi_ac_init);
355module_exit(acpi_ac_exit);