1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * battery.c - ACPI Battery Driver (Revision: 2.0)
4 *
5 * Copyright (C) 2007 Alexey Starikovskiy <astarikovskiy@suse.de>
6 * Copyright (C) 2004-2007 Vladimir Lebedev <vladimir.p.lebedev@intel.com>
7 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
8 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
9 */
10
11#define pr_fmt(fmt) "ACPI: battery: " fmt
12
13#include <linux/async.h>
14#include <linux/delay.h>
15#include <linux/dmi.h>
16#include <linux/jiffies.h>
17#include <linux/kernel.h>
18#include <linux/list.h>
19#include <linux/module.h>
20#include <linux/mutex.h>
21#include <linux/slab.h>
22#include <linux/suspend.h>
23#include <linux/types.h>
24
25#include <asm/unaligned.h>
26
27#include <linux/acpi.h>
28#include <linux/power_supply.h>
29
30#include <acpi/battery.h>
31
32#define ACPI_BATTERY_VALUE_UNKNOWN 0xFFFFFFFF
33#define ACPI_BATTERY_CAPACITY_VALID(capacity) \
34 ((capacity) != 0 && (capacity) != ACPI_BATTERY_VALUE_UNKNOWN)
35
36#define ACPI_BATTERY_DEVICE_NAME "Battery"
37
38/* Battery power unit: 0 means mW, 1 means mA */
39#define ACPI_BATTERY_POWER_UNIT_MA 1
40
41#define ACPI_BATTERY_STATE_DISCHARGING 0x1
42#define ACPI_BATTERY_STATE_CHARGING 0x2
43#define ACPI_BATTERY_STATE_CRITICAL 0x4
44
45#define MAX_STRING_LENGTH 64
46
47MODULE_AUTHOR("Paul Diefenbaugh");
48MODULE_AUTHOR("Alexey Starikovskiy <astarikovskiy@suse.de>");
49MODULE_DESCRIPTION("ACPI Battery Driver");
50MODULE_LICENSE("GPL");
51
52static async_cookie_t async_cookie;
53static bool battery_driver_registered;
54static int battery_bix_broken_package;
55static int battery_notification_delay_ms;
56static int battery_ac_is_broken;
57static unsigned int cache_time = 1000;
58module_param(cache_time, uint, 0644);
59MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
60
61static const struct acpi_device_id battery_device_ids[] = {
62 {"PNP0C0A", 0},
63
64 /* Microsoft Surface Go 3 */
65 {"MSHW0146", 0},
66
67 {"", 0},
68};
69
70MODULE_DEVICE_TABLE(acpi, battery_device_ids);
71
72enum {
73 ACPI_BATTERY_ALARM_PRESENT,
74 ACPI_BATTERY_XINFO_PRESENT,
75 ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY,
76 /* On Lenovo Thinkpad models from 2010 and 2011, the power unit
77 * switches between mWh and mAh depending on whether the system
78 * is running on battery or not. When mAh is the unit, most
79 * reported values are incorrect and need to be adjusted by
80 * 10000/design_voltage. Verified on x201, t410, t410s, and x220.
81 * Pre-2010 and 2012 models appear to always report in mWh and
82 * are thus unaffected (tested with t42, t61, t500, x200, x300,
83 * and x230). Also, in mid-2012 Lenovo issued a BIOS update for
84 * the 2011 models that fixes the issue (tested on x220 with a
85 * post-1.29 BIOS), but as of Nov. 2012, no such update is
86 * available for the 2010 models.
87 */
88 ACPI_BATTERY_QUIRK_THINKPAD_MAH,
89 /* for batteries reporting current capacity with design capacity
90 * on a full charge, but showing degradation in full charge cap.
91 */
92 ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE,
93};
94
95struct acpi_battery {
96 struct mutex lock;
97 struct mutex sysfs_lock;
98 struct power_supply *bat;
99 struct power_supply_desc bat_desc;
100 struct acpi_device *device;
101 struct notifier_block pm_nb;
102 struct list_head list;
103 unsigned long update_time;
104 int revision;
105 int rate_now;
106 int capacity_now;
107 int voltage_now;
108 int design_capacity;
109 int full_charge_capacity;
110 int technology;
111 int design_voltage;
112 int design_capacity_warning;
113 int design_capacity_low;
114 int cycle_count;
115 int measurement_accuracy;
116 int max_sampling_time;
117 int min_sampling_time;
118 int max_averaging_interval;
119 int min_averaging_interval;
120 int capacity_granularity_1;
121 int capacity_granularity_2;
122 int alarm;
123 char model_number[MAX_STRING_LENGTH];
124 char serial_number[MAX_STRING_LENGTH];
125 char type[MAX_STRING_LENGTH];
126 char oem_info[MAX_STRING_LENGTH];
127 int state;
128 int power_unit;
129 unsigned long flags;
130};
131
132#define to_acpi_battery(x) power_supply_get_drvdata(x)
133
134static inline int acpi_battery_present(struct acpi_battery *battery)
135{
136 return battery->device->status.battery_present;
137}
138
139static int acpi_battery_technology(struct acpi_battery *battery)
140{
141 if (!strcasecmp(s1: "NiCd", s2: battery->type))
142 return POWER_SUPPLY_TECHNOLOGY_NiCd;
143 if (!strcasecmp(s1: "NiMH", s2: battery->type))
144 return POWER_SUPPLY_TECHNOLOGY_NiMH;
145 if (!strcasecmp(s1: "LION", s2: battery->type))
146 return POWER_SUPPLY_TECHNOLOGY_LION;
147 if (!strncasecmp(s1: "LI-ION", s2: battery->type, n: 6))
148 return POWER_SUPPLY_TECHNOLOGY_LION;
149 if (!strcasecmp(s1: "LiP", s2: battery->type))
150 return POWER_SUPPLY_TECHNOLOGY_LIPO;
151 return POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
152}
153
154static int acpi_battery_get_state(struct acpi_battery *battery);
155
156static int acpi_battery_is_charged(struct acpi_battery *battery)
157{
158 /* charging, discharging or critical low */
159 if (battery->state != 0)
160 return 0;
161
162 /* battery not reporting charge */
163 if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN ||
164 battery->capacity_now == 0)
165 return 0;
166
167 /* good batteries update full_charge as the batteries degrade */
168 if (battery->full_charge_capacity == battery->capacity_now)
169 return 1;
170
171 /* fallback to using design values for broken batteries */
172 if (battery->design_capacity <= battery->capacity_now)
173 return 1;
174
175 /* we don't do any sort of metric based on percentages */
176 return 0;
177}
178
179static bool acpi_battery_is_degraded(struct acpi_battery *battery)
180{
181 return ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity) &&
182 ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity) &&
183 battery->full_charge_capacity < battery->design_capacity;
184}
185
186static int acpi_battery_handle_discharging(struct acpi_battery *battery)
187{
188 /*
189 * Some devices wrongly report discharging if the battery's charge level
190 * was above the device's start charging threshold atm the AC adapter
191 * was plugged in and the device thus did not start a new charge cycle.
192 */
193 if ((battery_ac_is_broken || power_supply_is_system_supplied()) &&
194 battery->rate_now == 0)
195 return POWER_SUPPLY_STATUS_NOT_CHARGING;
196
197 return POWER_SUPPLY_STATUS_DISCHARGING;
198}
199
200static int acpi_battery_get_property(struct power_supply *psy,
201 enum power_supply_property psp,
202 union power_supply_propval *val)
203{
204 int full_capacity = ACPI_BATTERY_VALUE_UNKNOWN, ret = 0;
205 struct acpi_battery *battery = to_acpi_battery(psy);
206
207 if (acpi_battery_present(battery)) {
208 /* run battery update only if it is present */
209 acpi_battery_get_state(battery);
210 } else if (psp != POWER_SUPPLY_PROP_PRESENT)
211 return -ENODEV;
212 switch (psp) {
213 case POWER_SUPPLY_PROP_STATUS:
214 if (battery->state & ACPI_BATTERY_STATE_DISCHARGING)
215 val->intval = acpi_battery_handle_discharging(battery);
216 else if (battery->state & ACPI_BATTERY_STATE_CHARGING)
217 val->intval = POWER_SUPPLY_STATUS_CHARGING;
218 else if (acpi_battery_is_charged(battery))
219 val->intval = POWER_SUPPLY_STATUS_FULL;
220 else
221 val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
222 break;
223 case POWER_SUPPLY_PROP_PRESENT:
224 val->intval = acpi_battery_present(battery);
225 break;
226 case POWER_SUPPLY_PROP_TECHNOLOGY:
227 val->intval = acpi_battery_technology(battery);
228 break;
229 case POWER_SUPPLY_PROP_CYCLE_COUNT:
230 val->intval = battery->cycle_count;
231 break;
232 case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
233 if (battery->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
234 ret = -ENODEV;
235 else
236 val->intval = battery->design_voltage * 1000;
237 break;
238 case POWER_SUPPLY_PROP_VOLTAGE_NOW:
239 if (battery->voltage_now == ACPI_BATTERY_VALUE_UNKNOWN)
240 ret = -ENODEV;
241 else
242 val->intval = battery->voltage_now * 1000;
243 break;
244 case POWER_SUPPLY_PROP_CURRENT_NOW:
245 case POWER_SUPPLY_PROP_POWER_NOW:
246 if (battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN)
247 ret = -ENODEV;
248 else
249 val->intval = battery->rate_now * 1000;
250 break;
251 case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
252 case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
253 if (!ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity))
254 ret = -ENODEV;
255 else
256 val->intval = battery->design_capacity * 1000;
257 break;
258 case POWER_SUPPLY_PROP_CHARGE_FULL:
259 case POWER_SUPPLY_PROP_ENERGY_FULL:
260 if (!ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity))
261 ret = -ENODEV;
262 else
263 val->intval = battery->full_charge_capacity * 1000;
264 break;
265 case POWER_SUPPLY_PROP_CHARGE_NOW:
266 case POWER_SUPPLY_PROP_ENERGY_NOW:
267 if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN)
268 ret = -ENODEV;
269 else
270 val->intval = battery->capacity_now * 1000;
271 break;
272 case POWER_SUPPLY_PROP_CAPACITY:
273 if (ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity))
274 full_capacity = battery->full_charge_capacity;
275 else if (ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity))
276 full_capacity = battery->design_capacity;
277
278 if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN ||
279 full_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
280 ret = -ENODEV;
281 else
282 val->intval = battery->capacity_now * 100/
283 full_capacity;
284 break;
285 case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
286 if (battery->state & ACPI_BATTERY_STATE_CRITICAL)
287 val->intval = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
288 else if (test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags) &&
289 (battery->capacity_now <= battery->alarm))
290 val->intval = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
291 else if (acpi_battery_is_charged(battery))
292 val->intval = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
293 else
294 val->intval = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
295 break;
296 case POWER_SUPPLY_PROP_MODEL_NAME:
297 val->strval = battery->model_number;
298 break;
299 case POWER_SUPPLY_PROP_MANUFACTURER:
300 val->strval = battery->oem_info;
301 break;
302 case POWER_SUPPLY_PROP_SERIAL_NUMBER:
303 val->strval = battery->serial_number;
304 break;
305 default:
306 ret = -EINVAL;
307 }
308 return ret;
309}
310
311static enum power_supply_property charge_battery_props[] = {
312 POWER_SUPPLY_PROP_STATUS,
313 POWER_SUPPLY_PROP_PRESENT,
314 POWER_SUPPLY_PROP_TECHNOLOGY,
315 POWER_SUPPLY_PROP_CYCLE_COUNT,
316 POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
317 POWER_SUPPLY_PROP_VOLTAGE_NOW,
318 POWER_SUPPLY_PROP_CURRENT_NOW,
319 POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
320 POWER_SUPPLY_PROP_CHARGE_FULL,
321 POWER_SUPPLY_PROP_CHARGE_NOW,
322 POWER_SUPPLY_PROP_CAPACITY,
323 POWER_SUPPLY_PROP_CAPACITY_LEVEL,
324 POWER_SUPPLY_PROP_MODEL_NAME,
325 POWER_SUPPLY_PROP_MANUFACTURER,
326 POWER_SUPPLY_PROP_SERIAL_NUMBER,
327};
328
329static enum power_supply_property charge_battery_full_cap_broken_props[] = {
330 POWER_SUPPLY_PROP_STATUS,
331 POWER_SUPPLY_PROP_PRESENT,
332 POWER_SUPPLY_PROP_TECHNOLOGY,
333 POWER_SUPPLY_PROP_CYCLE_COUNT,
334 POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
335 POWER_SUPPLY_PROP_VOLTAGE_NOW,
336 POWER_SUPPLY_PROP_CURRENT_NOW,
337 POWER_SUPPLY_PROP_CHARGE_NOW,
338 POWER_SUPPLY_PROP_MODEL_NAME,
339 POWER_SUPPLY_PROP_MANUFACTURER,
340 POWER_SUPPLY_PROP_SERIAL_NUMBER,
341};
342
343static enum power_supply_property energy_battery_props[] = {
344 POWER_SUPPLY_PROP_STATUS,
345 POWER_SUPPLY_PROP_PRESENT,
346 POWER_SUPPLY_PROP_TECHNOLOGY,
347 POWER_SUPPLY_PROP_CYCLE_COUNT,
348 POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
349 POWER_SUPPLY_PROP_VOLTAGE_NOW,
350 POWER_SUPPLY_PROP_POWER_NOW,
351 POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
352 POWER_SUPPLY_PROP_ENERGY_FULL,
353 POWER_SUPPLY_PROP_ENERGY_NOW,
354 POWER_SUPPLY_PROP_CAPACITY,
355 POWER_SUPPLY_PROP_CAPACITY_LEVEL,
356 POWER_SUPPLY_PROP_MODEL_NAME,
357 POWER_SUPPLY_PROP_MANUFACTURER,
358 POWER_SUPPLY_PROP_SERIAL_NUMBER,
359};
360
361static enum power_supply_property energy_battery_full_cap_broken_props[] = {
362 POWER_SUPPLY_PROP_STATUS,
363 POWER_SUPPLY_PROP_PRESENT,
364 POWER_SUPPLY_PROP_TECHNOLOGY,
365 POWER_SUPPLY_PROP_CYCLE_COUNT,
366 POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
367 POWER_SUPPLY_PROP_VOLTAGE_NOW,
368 POWER_SUPPLY_PROP_POWER_NOW,
369 POWER_SUPPLY_PROP_ENERGY_NOW,
370 POWER_SUPPLY_PROP_MODEL_NAME,
371 POWER_SUPPLY_PROP_MANUFACTURER,
372 POWER_SUPPLY_PROP_SERIAL_NUMBER,
373};
374
375/* Battery Management */
376struct acpi_offsets {
377 size_t offset; /* offset inside struct acpi_sbs_battery */
378 u8 mode; /* int or string? */
379};
380
381static const struct acpi_offsets state_offsets[] = {
382 {offsetof(struct acpi_battery, state), 0},
383 {offsetof(struct acpi_battery, rate_now), 0},
384 {offsetof(struct acpi_battery, capacity_now), 0},
385 {offsetof(struct acpi_battery, voltage_now), 0},
386};
387
388static const struct acpi_offsets info_offsets[] = {
389 {offsetof(struct acpi_battery, power_unit), 0},
390 {offsetof(struct acpi_battery, design_capacity), 0},
391 {offsetof(struct acpi_battery, full_charge_capacity), 0},
392 {offsetof(struct acpi_battery, technology), 0},
393 {offsetof(struct acpi_battery, design_voltage), 0},
394 {offsetof(struct acpi_battery, design_capacity_warning), 0},
395 {offsetof(struct acpi_battery, design_capacity_low), 0},
396 {offsetof(struct acpi_battery, capacity_granularity_1), 0},
397 {offsetof(struct acpi_battery, capacity_granularity_2), 0},
398 {offsetof(struct acpi_battery, model_number), 1},
399 {offsetof(struct acpi_battery, serial_number), 1},
400 {offsetof(struct acpi_battery, type), 1},
401 {offsetof(struct acpi_battery, oem_info), 1},
402};
403
404static const struct acpi_offsets extended_info_offsets[] = {
405 {offsetof(struct acpi_battery, revision), 0},
406 {offsetof(struct acpi_battery, power_unit), 0},
407 {offsetof(struct acpi_battery, design_capacity), 0},
408 {offsetof(struct acpi_battery, full_charge_capacity), 0},
409 {offsetof(struct acpi_battery, technology), 0},
410 {offsetof(struct acpi_battery, design_voltage), 0},
411 {offsetof(struct acpi_battery, design_capacity_warning), 0},
412 {offsetof(struct acpi_battery, design_capacity_low), 0},
413 {offsetof(struct acpi_battery, cycle_count), 0},
414 {offsetof(struct acpi_battery, measurement_accuracy), 0},
415 {offsetof(struct acpi_battery, max_sampling_time), 0},
416 {offsetof(struct acpi_battery, min_sampling_time), 0},
417 {offsetof(struct acpi_battery, max_averaging_interval), 0},
418 {offsetof(struct acpi_battery, min_averaging_interval), 0},
419 {offsetof(struct acpi_battery, capacity_granularity_1), 0},
420 {offsetof(struct acpi_battery, capacity_granularity_2), 0},
421 {offsetof(struct acpi_battery, model_number), 1},
422 {offsetof(struct acpi_battery, serial_number), 1},
423 {offsetof(struct acpi_battery, type), 1},
424 {offsetof(struct acpi_battery, oem_info), 1},
425};
426
427static int extract_package(struct acpi_battery *battery,
428 union acpi_object *package,
429 const struct acpi_offsets *offsets, int num)
430{
431 int i;
432 union acpi_object *element;
433
434 if (package->type != ACPI_TYPE_PACKAGE)
435 return -EFAULT;
436 for (i = 0; i < num; ++i) {
437 if (package->package.count <= i)
438 return -EFAULT;
439 element = &package->package.elements[i];
440 if (offsets[i].mode) {
441 u8 *ptr = (u8 *)battery + offsets[i].offset;
442 u32 len = MAX_STRING_LENGTH;
443
444 switch (element->type) {
445 case ACPI_TYPE_BUFFER:
446 if (len > element->buffer.length + 1)
447 len = element->buffer.length + 1;
448
449 fallthrough;
450 case ACPI_TYPE_STRING:
451 strscpy(ptr, element->string.pointer, len);
452
453 break;
454 case ACPI_TYPE_INTEGER:
455 strscpy(ptr, (u8 *)&element->integer.value, sizeof(u64) + 1);
456
457 break;
458 default:
459 *ptr = 0; /* don't have value */
460 }
461 } else {
462 int *x = (int *)((u8 *)battery + offsets[i].offset);
463 *x = (element->type == ACPI_TYPE_INTEGER) ?
464 element->integer.value : -1;
465 }
466 }
467 return 0;
468}
469
470static int acpi_battery_get_status(struct acpi_battery *battery)
471{
472 if (acpi_bus_get_status(device: battery->device)) {
473 acpi_handle_info(battery->device->handle,
474 "_STA evaluation failed\n");
475 return -ENODEV;
476 }
477 return 0;
478}
479
480
481static int extract_battery_info(const int use_bix,
482 struct acpi_battery *battery,
483 const struct acpi_buffer *buffer)
484{
485 int result = -EFAULT;
486
487 if (use_bix && battery_bix_broken_package)
488 result = extract_package(battery, package: buffer->pointer,
489 offsets: extended_info_offsets + 1,
490 ARRAY_SIZE(extended_info_offsets) - 1);
491 else if (use_bix)
492 result = extract_package(battery, package: buffer->pointer,
493 offsets: extended_info_offsets,
494 ARRAY_SIZE(extended_info_offsets));
495 else
496 result = extract_package(battery, package: buffer->pointer,
497 offsets: info_offsets, ARRAY_SIZE(info_offsets));
498 if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags))
499 battery->full_charge_capacity = battery->design_capacity;
500 if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH, &battery->flags) &&
501 battery->power_unit && battery->design_voltage) {
502 battery->design_capacity = battery->design_capacity *
503 10000 / battery->design_voltage;
504 battery->full_charge_capacity = battery->full_charge_capacity *
505 10000 / battery->design_voltage;
506 battery->design_capacity_warning =
507 battery->design_capacity_warning *
508 10000 / battery->design_voltage;
509 /* Curiously, design_capacity_low, unlike the rest of them,
510 * is correct.
511 */
512 /* capacity_granularity_* equal 1 on the systems tested, so
513 * it's impossible to tell if they would need an adjustment
514 * or not if their values were higher.
515 */
516 }
517 if (test_bit(ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE, &battery->flags) &&
518 battery->capacity_now > battery->full_charge_capacity)
519 battery->capacity_now = battery->full_charge_capacity;
520
521 return result;
522}
523
524static int acpi_battery_get_info(struct acpi_battery *battery)
525{
526 const int xinfo = test_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags);
527 int use_bix;
528 int result = -ENODEV;
529
530 if (!acpi_battery_present(battery))
531 return 0;
532
533
534 for (use_bix = xinfo ? 1 : 0; use_bix >= 0; use_bix--) {
535 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
536 acpi_status status = AE_ERROR;
537
538 mutex_lock(&battery->lock);
539 status = acpi_evaluate_object(object: battery->device->handle,
540 pathname: use_bix ? "_BIX":"_BIF",
541 NULL, return_object_buffer: &buffer);
542 mutex_unlock(lock: &battery->lock);
543
544 if (ACPI_FAILURE(status)) {
545 acpi_handle_info(battery->device->handle,
546 "%s evaluation failed: %s\n",
547 use_bix ? "_BIX":"_BIF",
548 acpi_format_exception(status));
549 } else {
550 result = extract_battery_info(use_bix,
551 battery,
552 buffer: &buffer);
553
554 kfree(objp: buffer.pointer);
555 break;
556 }
557 }
558
559 if (!result && !use_bix && xinfo)
560 pr_warn(FW_BUG "The _BIX method is broken, using _BIF.\n");
561
562 return result;
563}
564
565static int acpi_battery_get_state(struct acpi_battery *battery)
566{
567 int result = 0;
568 acpi_status status = 0;
569 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
570
571 if (!acpi_battery_present(battery))
572 return 0;
573
574 if (battery->update_time &&
575 time_before(jiffies, battery->update_time +
576 msecs_to_jiffies(cache_time)))
577 return 0;
578
579 mutex_lock(&battery->lock);
580 status = acpi_evaluate_object(object: battery->device->handle, pathname: "_BST",
581 NULL, return_object_buffer: &buffer);
582 mutex_unlock(lock: &battery->lock);
583
584 if (ACPI_FAILURE(status)) {
585 acpi_handle_info(battery->device->handle,
586 "_BST evaluation failed: %s",
587 acpi_format_exception(status));
588 return -ENODEV;
589 }
590
591 result = extract_package(battery, package: buffer.pointer,
592 offsets: state_offsets, ARRAY_SIZE(state_offsets));
593 battery->update_time = jiffies;
594 kfree(objp: buffer.pointer);
595
596 /* For buggy DSDTs that report negative 16-bit values for either
597 * charging or discharging current and/or report 0 as 65536
598 * due to bad math.
599 */
600 if (battery->power_unit == ACPI_BATTERY_POWER_UNIT_MA &&
601 battery->rate_now != ACPI_BATTERY_VALUE_UNKNOWN &&
602 (s16)(battery->rate_now) < 0) {
603 battery->rate_now = abs((s16)battery->rate_now);
604 pr_warn_once(FW_BUG "(dis)charge rate invalid.\n");
605 }
606
607 if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags)
608 && battery->capacity_now >= 0 && battery->capacity_now <= 100)
609 battery->capacity_now = (battery->capacity_now *
610 battery->full_charge_capacity) / 100;
611 if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH, &battery->flags) &&
612 battery->power_unit && battery->design_voltage) {
613 battery->capacity_now = battery->capacity_now *
614 10000 / battery->design_voltage;
615 }
616 if (test_bit(ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE, &battery->flags) &&
617 battery->capacity_now > battery->full_charge_capacity)
618 battery->capacity_now = battery->full_charge_capacity;
619
620 return result;
621}
622
623static int acpi_battery_set_alarm(struct acpi_battery *battery)
624{
625 acpi_status status = 0;
626
627 if (!acpi_battery_present(battery) ||
628 !test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags))
629 return -ENODEV;
630
631 mutex_lock(&battery->lock);
632 status = acpi_execute_simple_method(handle: battery->device->handle, method: "_BTP",
633 arg: battery->alarm);
634 mutex_unlock(lock: &battery->lock);
635
636 if (ACPI_FAILURE(status))
637 return -ENODEV;
638
639 acpi_handle_debug(battery->device->handle, "Alarm set to %d\n",
640 battery->alarm);
641
642 return 0;
643}
644
645static int acpi_battery_init_alarm(struct acpi_battery *battery)
646{
647 /* See if alarms are supported, and if so, set default */
648 if (!acpi_has_method(handle: battery->device->handle, name: "_BTP")) {
649 clear_bit(nr: ACPI_BATTERY_ALARM_PRESENT, addr: &battery->flags);
650 return 0;
651 }
652 set_bit(nr: ACPI_BATTERY_ALARM_PRESENT, addr: &battery->flags);
653 if (!battery->alarm)
654 battery->alarm = battery->design_capacity_warning;
655 return acpi_battery_set_alarm(battery);
656}
657
658static ssize_t acpi_battery_alarm_show(struct device *dev,
659 struct device_attribute *attr,
660 char *buf)
661{
662 struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
663
664 return sprintf(buf, fmt: "%d\n", battery->alarm * 1000);
665}
666
667static ssize_t acpi_battery_alarm_store(struct device *dev,
668 struct device_attribute *attr,
669 const char *buf, size_t count)
670{
671 unsigned long x;
672 struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
673
674 if (sscanf(buf, "%lu\n", &x) == 1)
675 battery->alarm = x/1000;
676 if (acpi_battery_present(battery))
677 acpi_battery_set_alarm(battery);
678 return count;
679}
680
681static const struct device_attribute alarm_attr = {
682 .attr = {.name = "alarm", .mode = 0644},
683 .show = acpi_battery_alarm_show,
684 .store = acpi_battery_alarm_store,
685};
686
687/*
688 * The Battery Hooking API
689 *
690 * This API is used inside other drivers that need to expose
691 * platform-specific behaviour within the generic driver in a
692 * generic way.
693 *
694 */
695
696static LIST_HEAD(acpi_battery_list);
697static LIST_HEAD(battery_hook_list);
698static DEFINE_MUTEX(hook_mutex);
699
700static void __battery_hook_unregister(struct acpi_battery_hook *hook, int lock)
701{
702 struct acpi_battery *battery;
703 /*
704 * In order to remove a hook, we first need to
705 * de-register all the batteries that are registered.
706 */
707 if (lock)
708 mutex_lock(&hook_mutex);
709 list_for_each_entry(battery, &acpi_battery_list, list) {
710 if (!hook->remove_battery(battery->bat, hook))
711 power_supply_changed(psy: battery->bat);
712 }
713 list_del(entry: &hook->list);
714 if (lock)
715 mutex_unlock(lock: &hook_mutex);
716 pr_info("extension unregistered: %s\n", hook->name);
717}
718
719void battery_hook_unregister(struct acpi_battery_hook *hook)
720{
721 __battery_hook_unregister(hook, lock: 1);
722}
723EXPORT_SYMBOL_GPL(battery_hook_unregister);
724
725void battery_hook_register(struct acpi_battery_hook *hook)
726{
727 struct acpi_battery *battery;
728
729 mutex_lock(&hook_mutex);
730 INIT_LIST_HEAD(list: &hook->list);
731 list_add(new: &hook->list, head: &battery_hook_list);
732 /*
733 * Now that the driver is registered, we need
734 * to notify the hook that a battery is available
735 * for each battery, so that the driver may add
736 * its attributes.
737 */
738 list_for_each_entry(battery, &acpi_battery_list, list) {
739 if (hook->add_battery(battery->bat, hook)) {
740 /*
741 * If a add-battery returns non-zero,
742 * the registration of the extension has failed,
743 * and we will not add it to the list of loaded
744 * hooks.
745 */
746 pr_err("extension failed to load: %s", hook->name);
747 __battery_hook_unregister(hook, lock: 0);
748 goto end;
749 }
750
751 power_supply_changed(psy: battery->bat);
752 }
753 pr_info("new extension: %s\n", hook->name);
754end:
755 mutex_unlock(lock: &hook_mutex);
756}
757EXPORT_SYMBOL_GPL(battery_hook_register);
758
759/*
760 * This function gets called right after the battery sysfs
761 * attributes have been added, so that the drivers that
762 * define custom sysfs attributes can add their own.
763 */
764static void battery_hook_add_battery(struct acpi_battery *battery)
765{
766 struct acpi_battery_hook *hook_node, *tmp;
767
768 mutex_lock(&hook_mutex);
769 INIT_LIST_HEAD(list: &battery->list);
770 list_add(new: &battery->list, head: &acpi_battery_list);
771 /*
772 * Since we added a new battery to the list, we need to
773 * iterate over the hooks and call add_battery for each
774 * hook that was registered. This usually happens
775 * when a battery gets hotplugged or initialized
776 * during the battery module initialization.
777 */
778 list_for_each_entry_safe(hook_node, tmp, &battery_hook_list, list) {
779 if (hook_node->add_battery(battery->bat, hook_node)) {
780 /*
781 * The notification of the extensions has failed, to
782 * prevent further errors we will unload the extension.
783 */
784 pr_err("error in extension, unloading: %s",
785 hook_node->name);
786 __battery_hook_unregister(hook: hook_node, lock: 0);
787 }
788 }
789 mutex_unlock(lock: &hook_mutex);
790}
791
792static void battery_hook_remove_battery(struct acpi_battery *battery)
793{
794 struct acpi_battery_hook *hook;
795
796 mutex_lock(&hook_mutex);
797 /*
798 * Before removing the hook, we need to remove all
799 * custom attributes from the battery.
800 */
801 list_for_each_entry(hook, &battery_hook_list, list) {
802 hook->remove_battery(battery->bat, hook);
803 }
804 /* Then, just remove the battery from the list */
805 list_del(entry: &battery->list);
806 mutex_unlock(lock: &hook_mutex);
807}
808
809static void __exit battery_hook_exit(void)
810{
811 struct acpi_battery_hook *hook;
812 struct acpi_battery_hook *ptr;
813 /*
814 * At this point, the acpi_bus_unregister_driver()
815 * has called remove for all batteries. We just
816 * need to remove the hooks.
817 */
818 list_for_each_entry_safe(hook, ptr, &battery_hook_list, list) {
819 __battery_hook_unregister(hook, lock: 1);
820 }
821 mutex_destroy(lock: &hook_mutex);
822}
823
824static int sysfs_add_battery(struct acpi_battery *battery)
825{
826 struct power_supply_config psy_cfg = { .drv_data = battery, };
827 bool full_cap_broken = false;
828
829 if (!ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity) &&
830 !ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity))
831 full_cap_broken = true;
832
833 if (battery->power_unit == ACPI_BATTERY_POWER_UNIT_MA) {
834 if (full_cap_broken) {
835 battery->bat_desc.properties =
836 charge_battery_full_cap_broken_props;
837 battery->bat_desc.num_properties =
838 ARRAY_SIZE(charge_battery_full_cap_broken_props);
839 } else {
840 battery->bat_desc.properties = charge_battery_props;
841 battery->bat_desc.num_properties =
842 ARRAY_SIZE(charge_battery_props);
843 }
844 } else {
845 if (full_cap_broken) {
846 battery->bat_desc.properties =
847 energy_battery_full_cap_broken_props;
848 battery->bat_desc.num_properties =
849 ARRAY_SIZE(energy_battery_full_cap_broken_props);
850 } else {
851 battery->bat_desc.properties = energy_battery_props;
852 battery->bat_desc.num_properties =
853 ARRAY_SIZE(energy_battery_props);
854 }
855 }
856
857 battery->bat_desc.name = acpi_device_bid(battery->device);
858 battery->bat_desc.type = POWER_SUPPLY_TYPE_BATTERY;
859 battery->bat_desc.get_property = acpi_battery_get_property;
860
861 battery->bat = power_supply_register_no_ws(parent: &battery->device->dev,
862 desc: &battery->bat_desc, cfg: &psy_cfg);
863
864 if (IS_ERR(ptr: battery->bat)) {
865 int result = PTR_ERR(ptr: battery->bat);
866
867 battery->bat = NULL;
868 return result;
869 }
870 battery_hook_add_battery(battery);
871 return device_create_file(device: &battery->bat->dev, entry: &alarm_attr);
872}
873
874static void sysfs_remove_battery(struct acpi_battery *battery)
875{
876 mutex_lock(&battery->sysfs_lock);
877 if (!battery->bat) {
878 mutex_unlock(lock: &battery->sysfs_lock);
879 return;
880 }
881 battery_hook_remove_battery(battery);
882 device_remove_file(dev: &battery->bat->dev, attr: &alarm_attr);
883 power_supply_unregister(psy: battery->bat);
884 battery->bat = NULL;
885 mutex_unlock(lock: &battery->sysfs_lock);
886}
887
888static void find_battery(const struct dmi_header *dm, void *private)
889{
890 struct acpi_battery *battery = (struct acpi_battery *)private;
891 /* Note: the hardcoded offsets below have been extracted from
892 * the source code of dmidecode.
893 */
894 if (dm->type == DMI_ENTRY_PORTABLE_BATTERY && dm->length >= 8) {
895 const u8 *dmi_data = (const u8 *)(dm + 1);
896 int dmi_capacity = get_unaligned((const u16 *)(dmi_data + 6));
897
898 if (dm->length >= 18)
899 dmi_capacity *= dmi_data[17];
900 if (battery->design_capacity * battery->design_voltage / 1000
901 != dmi_capacity &&
902 battery->design_capacity * 10 == dmi_capacity)
903 set_bit(nr: ACPI_BATTERY_QUIRK_THINKPAD_MAH,
904 addr: &battery->flags);
905 }
906}
907
908/*
909 * According to the ACPI spec, some kinds of primary batteries can
910 * report percentage battery remaining capacity directly to OS.
911 * In this case, it reports the Last Full Charged Capacity == 100
912 * and BatteryPresentRate == 0xFFFFFFFF.
913 *
914 * Now we found some battery reports percentage remaining capacity
915 * even if it's rechargeable.
916 * https://bugzilla.kernel.org/show_bug.cgi?id=15979
917 *
918 * Handle this correctly so that they won't break userspace.
919 */
920static void acpi_battery_quirks(struct acpi_battery *battery)
921{
922 if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags))
923 return;
924
925 if (battery->full_charge_capacity == 100 &&
926 battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN &&
927 battery->capacity_now >= 0 && battery->capacity_now <= 100) {
928 set_bit(nr: ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, addr: &battery->flags);
929 battery->full_charge_capacity = battery->design_capacity;
930 battery->capacity_now = (battery->capacity_now *
931 battery->full_charge_capacity) / 100;
932 }
933
934 if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH, &battery->flags))
935 return;
936
937 if (battery->power_unit && dmi_name_in_vendors(str: "LENOVO")) {
938 const char *s;
939
940 s = dmi_get_system_info(field: DMI_PRODUCT_VERSION);
941 if (s && !strncasecmp(s1: s, s2: "ThinkPad", n: 8)) {
942 dmi_walk(decode: find_battery, private_data: battery);
943 if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH,
944 &battery->flags) &&
945 battery->design_voltage) {
946 battery->design_capacity =
947 battery->design_capacity *
948 10000 / battery->design_voltage;
949 battery->full_charge_capacity =
950 battery->full_charge_capacity *
951 10000 / battery->design_voltage;
952 battery->design_capacity_warning =
953 battery->design_capacity_warning *
954 10000 / battery->design_voltage;
955 battery->capacity_now = battery->capacity_now *
956 10000 / battery->design_voltage;
957 }
958 }
959 }
960
961 if (test_bit(ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE, &battery->flags))
962 return;
963
964 if (acpi_battery_is_degraded(battery) &&
965 battery->capacity_now > battery->full_charge_capacity) {
966 set_bit(nr: ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE, addr: &battery->flags);
967 battery->capacity_now = battery->full_charge_capacity;
968 }
969}
970
971static int acpi_battery_update(struct acpi_battery *battery, bool resume)
972{
973 int result = acpi_battery_get_status(battery);
974
975 if (result)
976 return result;
977
978 if (!acpi_battery_present(battery)) {
979 sysfs_remove_battery(battery);
980 battery->update_time = 0;
981 return 0;
982 }
983
984 if (resume)
985 return 0;
986
987 if (!battery->update_time) {
988 result = acpi_battery_get_info(battery);
989 if (result)
990 return result;
991 acpi_battery_init_alarm(battery);
992 }
993
994 result = acpi_battery_get_state(battery);
995 if (result)
996 return result;
997 acpi_battery_quirks(battery);
998
999 if (!battery->bat) {
1000 result = sysfs_add_battery(battery);
1001 if (result)
1002 return result;
1003 }
1004
1005 /*
1006 * Wakeup the system if battery is critical low
1007 * or lower than the alarm level
1008 */
1009 if ((battery->state & ACPI_BATTERY_STATE_CRITICAL) ||
1010 (test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags) &&
1011 (battery->capacity_now <= battery->alarm)))
1012 acpi_pm_wakeup_event(dev: &battery->device->dev);
1013
1014 return result;
1015}
1016
1017static void acpi_battery_refresh(struct acpi_battery *battery)
1018{
1019 int power_unit;
1020
1021 if (!battery->bat)
1022 return;
1023
1024 power_unit = battery->power_unit;
1025
1026 acpi_battery_get_info(battery);
1027
1028 if (power_unit == battery->power_unit)
1029 return;
1030
1031 /* The battery has changed its reporting units. */
1032 sysfs_remove_battery(battery);
1033 sysfs_add_battery(battery);
1034}
1035
1036/* Driver Interface */
1037static void acpi_battery_notify(acpi_handle handle, u32 event, void *data)
1038{
1039 struct acpi_device *device = data;
1040 struct acpi_battery *battery = acpi_driver_data(d: device);
1041 struct power_supply *old;
1042
1043 if (!battery)
1044 return;
1045 old = battery->bat;
1046 /*
1047 * On Acer Aspire V5-573G notifications are sometimes triggered too
1048 * early. For example, when AC is unplugged and notification is
1049 * triggered, battery state is still reported as "Full", and changes to
1050 * "Discharging" only after short delay, without any notification.
1051 */
1052 if (battery_notification_delay_ms > 0)
1053 msleep(msecs: battery_notification_delay_ms);
1054 if (event == ACPI_BATTERY_NOTIFY_INFO)
1055 acpi_battery_refresh(battery);
1056 acpi_battery_update(battery, resume: false);
1057 acpi_bus_generate_netlink_event(device->pnp.device_class,
1058 dev_name(dev: &device->dev), event,
1059 acpi_battery_present(battery));
1060 acpi_notifier_call_chain(device, event, acpi_battery_present(battery));
1061 /* acpi_battery_update could remove power_supply object */
1062 if (old && battery->bat)
1063 power_supply_changed(psy: battery->bat);
1064}
1065
1066static int battery_notify(struct notifier_block *nb,
1067 unsigned long mode, void *_unused)
1068{
1069 struct acpi_battery *battery = container_of(nb, struct acpi_battery,
1070 pm_nb);
1071 int result;
1072
1073 switch (mode) {
1074 case PM_POST_HIBERNATION:
1075 case PM_POST_SUSPEND:
1076 if (!acpi_battery_present(battery))
1077 return 0;
1078
1079 if (battery->bat) {
1080 acpi_battery_refresh(battery);
1081 } else {
1082 result = acpi_battery_get_info(battery);
1083 if (result)
1084 return result;
1085
1086 result = sysfs_add_battery(battery);
1087 if (result)
1088 return result;
1089 }
1090
1091 acpi_battery_init_alarm(battery);
1092 acpi_battery_get_state(battery);
1093 break;
1094 }
1095
1096 return 0;
1097}
1098
1099static int __init
1100battery_bix_broken_package_quirk(const struct dmi_system_id *d)
1101{
1102 battery_bix_broken_package = 1;
1103 return 0;
1104}
1105
1106static int __init
1107battery_notification_delay_quirk(const struct dmi_system_id *d)
1108{
1109 battery_notification_delay_ms = 1000;
1110 return 0;
1111}
1112
1113static int __init
1114battery_ac_is_broken_quirk(const struct dmi_system_id *d)
1115{
1116 battery_ac_is_broken = 1;
1117 return 0;
1118}
1119
1120static const struct dmi_system_id bat_dmi_table[] __initconst = {
1121 {
1122 /* NEC LZ750/LS */
1123 .callback = battery_bix_broken_package_quirk,
1124 .matches = {
1125 DMI_MATCH(DMI_SYS_VENDOR, "NEC"),
1126 DMI_MATCH(DMI_PRODUCT_NAME, "PC-LZ750LS"),
1127 },
1128 },
1129 {
1130 /* Acer Aspire V5-573G */
1131 .callback = battery_notification_delay_quirk,
1132 .matches = {
1133 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
1134 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire V5-573G"),
1135 },
1136 },
1137 {
1138 /* Point of View mobii wintab p800w */
1139 .callback = battery_ac_is_broken_quirk,
1140 .matches = {
1141 DMI_MATCH(DMI_BOARD_VENDOR, "AMI Corporation"),
1142 DMI_MATCH(DMI_BOARD_NAME, "Aptio CRB"),
1143 DMI_MATCH(DMI_BIOS_VERSION, "3BAIR1013"),
1144 /* Above matches are too generic, add bios-date match */
1145 DMI_MATCH(DMI_BIOS_DATE, "08/22/2014"),
1146 },
1147 },
1148 {
1149 /* Microsoft Surface Go 3 */
1150 .callback = battery_notification_delay_quirk,
1151 .matches = {
1152 DMI_MATCH(DMI_SYS_VENDOR, "Microsoft Corporation"),
1153 DMI_MATCH(DMI_PRODUCT_NAME, "Surface Go 3"),
1154 },
1155 },
1156 {},
1157};
1158
1159/*
1160 * Some machines'(E,G Lenovo Z480) ECs are not stable
1161 * during boot up and this causes battery driver fails to be
1162 * probed due to failure of getting battery information
1163 * from EC sometimes. After several retries, the operation
1164 * may work. So add retry code here and 20ms sleep between
1165 * every retries.
1166 */
1167static int acpi_battery_update_retry(struct acpi_battery *battery)
1168{
1169 int retry, ret;
1170
1171 for (retry = 5; retry; retry--) {
1172 ret = acpi_battery_update(battery, resume: false);
1173 if (!ret)
1174 break;
1175
1176 msleep(msecs: 20);
1177 }
1178 return ret;
1179}
1180
1181static int acpi_battery_add(struct acpi_device *device)
1182{
1183 int result = 0;
1184 struct acpi_battery *battery = NULL;
1185
1186 if (!device)
1187 return -EINVAL;
1188
1189 if (device->dep_unmet)
1190 return -EPROBE_DEFER;
1191
1192 battery = kzalloc(size: sizeof(struct acpi_battery), GFP_KERNEL);
1193 if (!battery)
1194 return -ENOMEM;
1195 battery->device = device;
1196 strcpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
1197 strcpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
1198 device->driver_data = battery;
1199 mutex_init(&battery->lock);
1200 mutex_init(&battery->sysfs_lock);
1201 if (acpi_has_method(handle: battery->device->handle, name: "_BIX"))
1202 set_bit(nr: ACPI_BATTERY_XINFO_PRESENT, addr: &battery->flags);
1203
1204 result = acpi_battery_update_retry(battery);
1205 if (result)
1206 goto fail;
1207
1208 pr_info("Slot [%s] (battery %s)\n", acpi_device_bid(device),
1209 device->status.battery_present ? "present" : "absent");
1210
1211 battery->pm_nb.notifier_call = battery_notify;
1212 register_pm_notifier(nb: &battery->pm_nb);
1213
1214 device_init_wakeup(dev: &device->dev, enable: 1);
1215
1216 result = acpi_dev_install_notify_handler(adev: device, ACPI_ALL_NOTIFY,
1217 handler: acpi_battery_notify, context: device);
1218 if (result)
1219 goto fail_pm;
1220
1221 return 0;
1222
1223fail_pm:
1224 device_init_wakeup(dev: &device->dev, enable: 0);
1225 unregister_pm_notifier(nb: &battery->pm_nb);
1226fail:
1227 sysfs_remove_battery(battery);
1228 mutex_destroy(lock: &battery->lock);
1229 mutex_destroy(lock: &battery->sysfs_lock);
1230 kfree(objp: battery);
1231
1232 return result;
1233}
1234
1235static void acpi_battery_remove(struct acpi_device *device)
1236{
1237 struct acpi_battery *battery = NULL;
1238
1239 if (!device || !acpi_driver_data(d: device))
1240 return;
1241
1242 battery = acpi_driver_data(d: device);
1243
1244 acpi_dev_remove_notify_handler(adev: device, ACPI_ALL_NOTIFY,
1245 handler: acpi_battery_notify);
1246
1247 device_init_wakeup(dev: &device->dev, enable: 0);
1248 unregister_pm_notifier(nb: &battery->pm_nb);
1249 sysfs_remove_battery(battery);
1250
1251 mutex_destroy(lock: &battery->lock);
1252 mutex_destroy(lock: &battery->sysfs_lock);
1253 kfree(objp: battery);
1254}
1255
1256#ifdef CONFIG_PM_SLEEP
1257/* this is needed to learn about changes made in suspended state */
1258static int acpi_battery_resume(struct device *dev)
1259{
1260 struct acpi_battery *battery;
1261
1262 if (!dev)
1263 return -EINVAL;
1264
1265 battery = acpi_driver_data(to_acpi_device(dev));
1266 if (!battery)
1267 return -EINVAL;
1268
1269 battery->update_time = 0;
1270 acpi_battery_update(battery, resume: true);
1271 return 0;
1272}
1273#else
1274#define acpi_battery_resume NULL
1275#endif
1276
1277static SIMPLE_DEV_PM_OPS(acpi_battery_pm, NULL, acpi_battery_resume);
1278
1279static struct acpi_driver acpi_battery_driver = {
1280 .name = "battery",
1281 .class = ACPI_BATTERY_CLASS,
1282 .ids = battery_device_ids,
1283 .ops = {
1284 .add = acpi_battery_add,
1285 .remove = acpi_battery_remove,
1286 },
1287 .drv.pm = &acpi_battery_pm,
1288};
1289
1290static void __init acpi_battery_init_async(void *unused, async_cookie_t cookie)
1291{
1292 int result;
1293
1294 if (acpi_quirk_skip_acpi_ac_and_battery())
1295 return;
1296
1297 dmi_check_system(list: bat_dmi_table);
1298
1299 result = acpi_bus_register_driver(driver: &acpi_battery_driver);
1300 battery_driver_registered = (result == 0);
1301}
1302
1303static int __init acpi_battery_init(void)
1304{
1305 if (acpi_disabled)
1306 return -ENODEV;
1307
1308 async_cookie = async_schedule(func: acpi_battery_init_async, NULL);
1309 return 0;
1310}
1311
1312static void __exit acpi_battery_exit(void)
1313{
1314 async_synchronize_cookie(cookie: async_cookie + 1);
1315 if (battery_driver_registered) {
1316 acpi_bus_unregister_driver(driver: &acpi_battery_driver);
1317 battery_hook_exit();
1318 }
1319}
1320
1321module_init(acpi_battery_init);
1322module_exit(acpi_battery_exit);
1323

source code of linux/drivers/acpi/battery.c