Merge tag 'wireless-2022-11-28' of git://git.kernel.org/pub/scm/linux/kernel/git...
[platform/kernel/linux-starfive.git] / drivers / acpi / battery.c
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 MODULE_AUTHOR("Paul Diefenbaugh");
46 MODULE_AUTHOR("Alexey Starikovskiy <astarikovskiy@suse.de>");
47 MODULE_DESCRIPTION("ACPI Battery Driver");
48 MODULE_LICENSE("GPL");
49
50 static async_cookie_t async_cookie;
51 static bool battery_driver_registered;
52 static int battery_bix_broken_package;
53 static int battery_notification_delay_ms;
54 static int battery_ac_is_broken;
55 static unsigned int cache_time = 1000;
56 module_param(cache_time, uint, 0644);
57 MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
58
59 static const struct acpi_device_id battery_device_ids[] = {
60         {"PNP0C0A", 0},
61
62         /* Microsoft Surface Go 3 */
63         {"MSHW0146", 0},
64
65         {"", 0},
66 };
67
68 MODULE_DEVICE_TABLE(acpi, battery_device_ids);
69
70 enum {
71         ACPI_BATTERY_ALARM_PRESENT,
72         ACPI_BATTERY_XINFO_PRESENT,
73         ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY,
74         /* On Lenovo Thinkpad models from 2010 and 2011, the power unit
75          * switches between mWh and mAh depending on whether the system
76          * is running on battery or not.  When mAh is the unit, most
77          * reported values are incorrect and need to be adjusted by
78          * 10000/design_voltage.  Verified on x201, t410, t410s, and x220.
79          * Pre-2010 and 2012 models appear to always report in mWh and
80          * are thus unaffected (tested with t42, t61, t500, x200, x300,
81          * and x230).  Also, in mid-2012 Lenovo issued a BIOS update for
82          *  the 2011 models that fixes the issue (tested on x220 with a
83          * post-1.29 BIOS), but as of Nov. 2012, no such update is
84          * available for the 2010 models.
85          */
86         ACPI_BATTERY_QUIRK_THINKPAD_MAH,
87         /* for batteries reporting current capacity with design capacity
88          * on a full charge, but showing degradation in full charge cap.
89          */
90         ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE,
91 };
92
93 struct acpi_battery {
94         struct mutex lock;
95         struct mutex sysfs_lock;
96         struct power_supply *bat;
97         struct power_supply_desc bat_desc;
98         struct acpi_device *device;
99         struct notifier_block pm_nb;
100         struct list_head list;
101         unsigned long update_time;
102         int revision;
103         int rate_now;
104         int capacity_now;
105         int voltage_now;
106         int design_capacity;
107         int full_charge_capacity;
108         int technology;
109         int design_voltage;
110         int design_capacity_warning;
111         int design_capacity_low;
112         int cycle_count;
113         int measurement_accuracy;
114         int max_sampling_time;
115         int min_sampling_time;
116         int max_averaging_interval;
117         int min_averaging_interval;
118         int capacity_granularity_1;
119         int capacity_granularity_2;
120         int alarm;
121         char model_number[32];
122         char serial_number[32];
123         char type[32];
124         char oem_info[32];
125         int state;
126         int power_unit;
127         unsigned long flags;
128 };
129
130 #define to_acpi_battery(x) power_supply_get_drvdata(x)
131
132 static inline int acpi_battery_present(struct acpi_battery *battery)
133 {
134         return battery->device->status.battery_present;
135 }
136
137 static int acpi_battery_technology(struct acpi_battery *battery)
138 {
139         if (!strcasecmp("NiCd", battery->type))
140                 return POWER_SUPPLY_TECHNOLOGY_NiCd;
141         if (!strcasecmp("NiMH", battery->type))
142                 return POWER_SUPPLY_TECHNOLOGY_NiMH;
143         if (!strcasecmp("LION", battery->type))
144                 return POWER_SUPPLY_TECHNOLOGY_LION;
145         if (!strncasecmp("LI-ION", battery->type, 6))
146                 return POWER_SUPPLY_TECHNOLOGY_LION;
147         if (!strcasecmp("LiP", battery->type))
148                 return POWER_SUPPLY_TECHNOLOGY_LIPO;
149         return POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
150 }
151
152 static int acpi_battery_get_state(struct acpi_battery *battery);
153
154 static int acpi_battery_is_charged(struct acpi_battery *battery)
155 {
156         /* charging, discharging or critical low */
157         if (battery->state != 0)
158                 return 0;
159
160         /* battery not reporting charge */
161         if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN ||
162             battery->capacity_now == 0)
163                 return 0;
164
165         /* good batteries update full_charge as the batteries degrade */
166         if (battery->full_charge_capacity == battery->capacity_now)
167                 return 1;
168
169         /* fallback to using design values for broken batteries */
170         if (battery->design_capacity <= battery->capacity_now)
171                 return 1;
172
173         /* we don't do any sort of metric based on percentages */
174         return 0;
175 }
176
177 static bool acpi_battery_is_degraded(struct acpi_battery *battery)
178 {
179         return ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity) &&
180                 ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity) &&
181                 battery->full_charge_capacity < battery->design_capacity;
182 }
183
184 static int acpi_battery_handle_discharging(struct acpi_battery *battery)
185 {
186         /*
187          * Some devices wrongly report discharging if the battery's charge level
188          * was above the device's start charging threshold atm the AC adapter
189          * was plugged in and the device thus did not start a new charge cycle.
190          */
191         if ((battery_ac_is_broken || power_supply_is_system_supplied()) &&
192             battery->rate_now == 0)
193                 return POWER_SUPPLY_STATUS_NOT_CHARGING;
194
195         return POWER_SUPPLY_STATUS_DISCHARGING;
196 }
197
198 static int acpi_battery_get_property(struct power_supply *psy,
199                                      enum power_supply_property psp,
200                                      union power_supply_propval *val)
201 {
202         int full_capacity = ACPI_BATTERY_VALUE_UNKNOWN, ret = 0;
203         struct acpi_battery *battery = to_acpi_battery(psy);
204
205         if (acpi_battery_present(battery)) {
206                 /* run battery update only if it is present */
207                 acpi_battery_get_state(battery);
208         } else if (psp != POWER_SUPPLY_PROP_PRESENT)
209                 return -ENODEV;
210         switch (psp) {
211         case POWER_SUPPLY_PROP_STATUS:
212                 if (battery->state & ACPI_BATTERY_STATE_DISCHARGING)
213                         val->intval = acpi_battery_handle_discharging(battery);
214                 else if (battery->state & ACPI_BATTERY_STATE_CHARGING)
215                         val->intval = POWER_SUPPLY_STATUS_CHARGING;
216                 else if (acpi_battery_is_charged(battery))
217                         val->intval = POWER_SUPPLY_STATUS_FULL;
218                 else
219                         val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
220                 break;
221         case POWER_SUPPLY_PROP_PRESENT:
222                 val->intval = acpi_battery_present(battery);
223                 break;
224         case POWER_SUPPLY_PROP_TECHNOLOGY:
225                 val->intval = acpi_battery_technology(battery);
226                 break;
227         case POWER_SUPPLY_PROP_CYCLE_COUNT:
228                 val->intval = battery->cycle_count;
229                 break;
230         case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
231                 if (battery->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
232                         ret = -ENODEV;
233                 else
234                         val->intval = battery->design_voltage * 1000;
235                 break;
236         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
237                 if (battery->voltage_now == ACPI_BATTERY_VALUE_UNKNOWN)
238                         ret = -ENODEV;
239                 else
240                         val->intval = battery->voltage_now * 1000;
241                 break;
242         case POWER_SUPPLY_PROP_CURRENT_NOW:
243         case POWER_SUPPLY_PROP_POWER_NOW:
244                 if (battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN)
245                         ret = -ENODEV;
246                 else
247                         val->intval = battery->rate_now * 1000;
248                 break;
249         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
250         case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
251                 if (!ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity))
252                         ret = -ENODEV;
253                 else
254                         val->intval = battery->design_capacity * 1000;
255                 break;
256         case POWER_SUPPLY_PROP_CHARGE_FULL:
257         case POWER_SUPPLY_PROP_ENERGY_FULL:
258                 if (!ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity))
259                         ret = -ENODEV;
260                 else
261                         val->intval = battery->full_charge_capacity * 1000;
262                 break;
263         case POWER_SUPPLY_PROP_CHARGE_NOW:
264         case POWER_SUPPLY_PROP_ENERGY_NOW:
265                 if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN)
266                         ret = -ENODEV;
267                 else
268                         val->intval = battery->capacity_now * 1000;
269                 break;
270         case POWER_SUPPLY_PROP_CAPACITY:
271                 if (ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity))
272                         full_capacity = battery->full_charge_capacity;
273                 else if (ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity))
274                         full_capacity = battery->design_capacity;
275
276                 if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN ||
277                     full_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
278                         ret = -ENODEV;
279                 else
280                         val->intval = battery->capacity_now * 100/
281                                         full_capacity;
282                 break;
283         case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
284                 if (battery->state & ACPI_BATTERY_STATE_CRITICAL)
285                         val->intval = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
286                 else if (test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags) &&
287                         (battery->capacity_now <= battery->alarm))
288                         val->intval = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
289                 else if (acpi_battery_is_charged(battery))
290                         val->intval = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
291                 else
292                         val->intval = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
293                 break;
294         case POWER_SUPPLY_PROP_MODEL_NAME:
295                 val->strval = battery->model_number;
296                 break;
297         case POWER_SUPPLY_PROP_MANUFACTURER:
298                 val->strval = battery->oem_info;
299                 break;
300         case POWER_SUPPLY_PROP_SERIAL_NUMBER:
301                 val->strval = battery->serial_number;
302                 break;
303         default:
304                 ret = -EINVAL;
305         }
306         return ret;
307 }
308
309 static enum power_supply_property charge_battery_props[] = {
310         POWER_SUPPLY_PROP_STATUS,
311         POWER_SUPPLY_PROP_PRESENT,
312         POWER_SUPPLY_PROP_TECHNOLOGY,
313         POWER_SUPPLY_PROP_CYCLE_COUNT,
314         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
315         POWER_SUPPLY_PROP_VOLTAGE_NOW,
316         POWER_SUPPLY_PROP_CURRENT_NOW,
317         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
318         POWER_SUPPLY_PROP_CHARGE_FULL,
319         POWER_SUPPLY_PROP_CHARGE_NOW,
320         POWER_SUPPLY_PROP_CAPACITY,
321         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
322         POWER_SUPPLY_PROP_MODEL_NAME,
323         POWER_SUPPLY_PROP_MANUFACTURER,
324         POWER_SUPPLY_PROP_SERIAL_NUMBER,
325 };
326
327 static enum power_supply_property charge_battery_full_cap_broken_props[] = {
328         POWER_SUPPLY_PROP_STATUS,
329         POWER_SUPPLY_PROP_PRESENT,
330         POWER_SUPPLY_PROP_TECHNOLOGY,
331         POWER_SUPPLY_PROP_CYCLE_COUNT,
332         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
333         POWER_SUPPLY_PROP_VOLTAGE_NOW,
334         POWER_SUPPLY_PROP_CURRENT_NOW,
335         POWER_SUPPLY_PROP_CHARGE_NOW,
336         POWER_SUPPLY_PROP_MODEL_NAME,
337         POWER_SUPPLY_PROP_MANUFACTURER,
338         POWER_SUPPLY_PROP_SERIAL_NUMBER,
339 };
340
341 static enum power_supply_property energy_battery_props[] = {
342         POWER_SUPPLY_PROP_STATUS,
343         POWER_SUPPLY_PROP_PRESENT,
344         POWER_SUPPLY_PROP_TECHNOLOGY,
345         POWER_SUPPLY_PROP_CYCLE_COUNT,
346         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
347         POWER_SUPPLY_PROP_VOLTAGE_NOW,
348         POWER_SUPPLY_PROP_POWER_NOW,
349         POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
350         POWER_SUPPLY_PROP_ENERGY_FULL,
351         POWER_SUPPLY_PROP_ENERGY_NOW,
352         POWER_SUPPLY_PROP_CAPACITY,
353         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
354         POWER_SUPPLY_PROP_MODEL_NAME,
355         POWER_SUPPLY_PROP_MANUFACTURER,
356         POWER_SUPPLY_PROP_SERIAL_NUMBER,
357 };
358
359 static enum power_supply_property energy_battery_full_cap_broken_props[] = {
360         POWER_SUPPLY_PROP_STATUS,
361         POWER_SUPPLY_PROP_PRESENT,
362         POWER_SUPPLY_PROP_TECHNOLOGY,
363         POWER_SUPPLY_PROP_CYCLE_COUNT,
364         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
365         POWER_SUPPLY_PROP_VOLTAGE_NOW,
366         POWER_SUPPLY_PROP_POWER_NOW,
367         POWER_SUPPLY_PROP_ENERGY_NOW,
368         POWER_SUPPLY_PROP_MODEL_NAME,
369         POWER_SUPPLY_PROP_MANUFACTURER,
370         POWER_SUPPLY_PROP_SERIAL_NUMBER,
371 };
372
373 /* Battery Management */
374 struct acpi_offsets {
375         size_t offset;          /* offset inside struct acpi_sbs_battery */
376         u8 mode;                /* int or string? */
377 };
378
379 static const struct acpi_offsets state_offsets[] = {
380         {offsetof(struct acpi_battery, state), 0},
381         {offsetof(struct acpi_battery, rate_now), 0},
382         {offsetof(struct acpi_battery, capacity_now), 0},
383         {offsetof(struct acpi_battery, voltage_now), 0},
384 };
385
386 static const struct acpi_offsets info_offsets[] = {
387         {offsetof(struct acpi_battery, power_unit), 0},
388         {offsetof(struct acpi_battery, design_capacity), 0},
389         {offsetof(struct acpi_battery, full_charge_capacity), 0},
390         {offsetof(struct acpi_battery, technology), 0},
391         {offsetof(struct acpi_battery, design_voltage), 0},
392         {offsetof(struct acpi_battery, design_capacity_warning), 0},
393         {offsetof(struct acpi_battery, design_capacity_low), 0},
394         {offsetof(struct acpi_battery, capacity_granularity_1), 0},
395         {offsetof(struct acpi_battery, capacity_granularity_2), 0},
396         {offsetof(struct acpi_battery, model_number), 1},
397         {offsetof(struct acpi_battery, serial_number), 1},
398         {offsetof(struct acpi_battery, type), 1},
399         {offsetof(struct acpi_battery, oem_info), 1},
400 };
401
402 static const struct acpi_offsets extended_info_offsets[] = {
403         {offsetof(struct acpi_battery, revision), 0},
404         {offsetof(struct acpi_battery, power_unit), 0},
405         {offsetof(struct acpi_battery, design_capacity), 0},
406         {offsetof(struct acpi_battery, full_charge_capacity), 0},
407         {offsetof(struct acpi_battery, technology), 0},
408         {offsetof(struct acpi_battery, design_voltage), 0},
409         {offsetof(struct acpi_battery, design_capacity_warning), 0},
410         {offsetof(struct acpi_battery, design_capacity_low), 0},
411         {offsetof(struct acpi_battery, cycle_count), 0},
412         {offsetof(struct acpi_battery, measurement_accuracy), 0},
413         {offsetof(struct acpi_battery, max_sampling_time), 0},
414         {offsetof(struct acpi_battery, min_sampling_time), 0},
415         {offsetof(struct acpi_battery, max_averaging_interval), 0},
416         {offsetof(struct acpi_battery, min_averaging_interval), 0},
417         {offsetof(struct acpi_battery, capacity_granularity_1), 0},
418         {offsetof(struct acpi_battery, capacity_granularity_2), 0},
419         {offsetof(struct acpi_battery, model_number), 1},
420         {offsetof(struct acpi_battery, serial_number), 1},
421         {offsetof(struct acpi_battery, type), 1},
422         {offsetof(struct acpi_battery, oem_info), 1},
423 };
424
425 static int extract_package(struct acpi_battery *battery,
426                            union acpi_object *package,
427                            const struct acpi_offsets *offsets, int num)
428 {
429         int i;
430         union acpi_object *element;
431
432         if (package->type != ACPI_TYPE_PACKAGE)
433                 return -EFAULT;
434         for (i = 0; i < num; ++i) {
435                 if (package->package.count <= i)
436                         return -EFAULT;
437                 element = &package->package.elements[i];
438                 if (offsets[i].mode) {
439                         u8 *ptr = (u8 *)battery + offsets[i].offset;
440
441                         if (element->type == ACPI_TYPE_STRING ||
442                             element->type == ACPI_TYPE_BUFFER)
443                                 strncpy(ptr, element->string.pointer, 32);
444                         else if (element->type == ACPI_TYPE_INTEGER) {
445                                 strncpy(ptr, (u8 *)&element->integer.value,
446                                         sizeof(u64));
447                                 ptr[sizeof(u64)] = 0;
448                         } else
449                                 *ptr = 0; /* don't have value */
450                 } else {
451                         int *x = (int *)((u8 *)battery + offsets[i].offset);
452                         *x = (element->type == ACPI_TYPE_INTEGER) ?
453                                 element->integer.value : -1;
454                 }
455         }
456         return 0;
457 }
458
459 static int acpi_battery_get_status(struct acpi_battery *battery)
460 {
461         if (acpi_bus_get_status(battery->device)) {
462                 acpi_handle_info(battery->device->handle,
463                                  "_STA evaluation failed\n");
464                 return -ENODEV;
465         }
466         return 0;
467 }
468
469
470 static int extract_battery_info(const int use_bix,
471                          struct acpi_battery *battery,
472                          const struct acpi_buffer *buffer)
473 {
474         int result = -EFAULT;
475
476         if (use_bix && battery_bix_broken_package)
477                 result = extract_package(battery, buffer->pointer,
478                                 extended_info_offsets + 1,
479                                 ARRAY_SIZE(extended_info_offsets) - 1);
480         else if (use_bix)
481                 result = extract_package(battery, buffer->pointer,
482                                 extended_info_offsets,
483                                 ARRAY_SIZE(extended_info_offsets));
484         else
485                 result = extract_package(battery, buffer->pointer,
486                                 info_offsets, ARRAY_SIZE(info_offsets));
487         if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags))
488                 battery->full_charge_capacity = battery->design_capacity;
489         if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH, &battery->flags) &&
490             battery->power_unit && battery->design_voltage) {
491                 battery->design_capacity = battery->design_capacity *
492                     10000 / battery->design_voltage;
493                 battery->full_charge_capacity = battery->full_charge_capacity *
494                     10000 / battery->design_voltage;
495                 battery->design_capacity_warning =
496                     battery->design_capacity_warning *
497                     10000 / battery->design_voltage;
498                 /* Curiously, design_capacity_low, unlike the rest of them,
499                  *  is correct.
500                  */
501                 /* capacity_granularity_* equal 1 on the systems tested, so
502                  * it's impossible to tell if they would need an adjustment
503                  * or not if their values were higher.
504                  */
505         }
506         if (test_bit(ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE, &battery->flags) &&
507             battery->capacity_now > battery->full_charge_capacity)
508                 battery->capacity_now = battery->full_charge_capacity;
509
510         return result;
511 }
512
513 static int acpi_battery_get_info(struct acpi_battery *battery)
514 {
515         const int xinfo = test_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags);
516         int use_bix;
517         int result = -ENODEV;
518
519         if (!acpi_battery_present(battery))
520                 return 0;
521
522
523         for (use_bix = xinfo ? 1 : 0; use_bix >= 0; use_bix--) {
524                 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
525                 acpi_status status = AE_ERROR;
526
527                 mutex_lock(&battery->lock);
528                 status = acpi_evaluate_object(battery->device->handle,
529                                               use_bix ? "_BIX":"_BIF",
530                                               NULL, &buffer);
531                 mutex_unlock(&battery->lock);
532
533                 if (ACPI_FAILURE(status)) {
534                         acpi_handle_info(battery->device->handle,
535                                          "%s evaluation failed: %s\n",
536                                          use_bix ? "_BIX":"_BIF",
537                                          acpi_format_exception(status));
538                 } else {
539                         result = extract_battery_info(use_bix,
540                                                       battery,
541                                                       &buffer);
542
543                         kfree(buffer.pointer);
544                         break;
545                 }
546         }
547
548         if (!result && !use_bix && xinfo)
549                 pr_warn(FW_BUG "The _BIX method is broken, using _BIF.\n");
550
551         return result;
552 }
553
554 static int acpi_battery_get_state(struct acpi_battery *battery)
555 {
556         int result = 0;
557         acpi_status status = 0;
558         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
559
560         if (!acpi_battery_present(battery))
561                 return 0;
562
563         if (battery->update_time &&
564             time_before(jiffies, battery->update_time +
565                         msecs_to_jiffies(cache_time)))
566                 return 0;
567
568         mutex_lock(&battery->lock);
569         status = acpi_evaluate_object(battery->device->handle, "_BST",
570                                       NULL, &buffer);
571         mutex_unlock(&battery->lock);
572
573         if (ACPI_FAILURE(status)) {
574                 acpi_handle_info(battery->device->handle,
575                                  "_BST evaluation failed: %s",
576                                  acpi_format_exception(status));
577                 return -ENODEV;
578         }
579
580         result = extract_package(battery, buffer.pointer,
581                                  state_offsets, ARRAY_SIZE(state_offsets));
582         battery->update_time = jiffies;
583         kfree(buffer.pointer);
584
585         /* For buggy DSDTs that report negative 16-bit values for either
586          * charging or discharging current and/or report 0 as 65536
587          * due to bad math.
588          */
589         if (battery->power_unit == ACPI_BATTERY_POWER_UNIT_MA &&
590                 battery->rate_now != ACPI_BATTERY_VALUE_UNKNOWN &&
591                 (s16)(battery->rate_now) < 0) {
592                 battery->rate_now = abs((s16)battery->rate_now);
593                 pr_warn_once(FW_BUG "(dis)charge rate invalid.\n");
594         }
595
596         if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags)
597             && battery->capacity_now >= 0 && battery->capacity_now <= 100)
598                 battery->capacity_now = (battery->capacity_now *
599                                 battery->full_charge_capacity) / 100;
600         if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH, &battery->flags) &&
601             battery->power_unit && battery->design_voltage) {
602                 battery->capacity_now = battery->capacity_now *
603                     10000 / battery->design_voltage;
604         }
605         if (test_bit(ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE, &battery->flags) &&
606             battery->capacity_now > battery->full_charge_capacity)
607                 battery->capacity_now = battery->full_charge_capacity;
608
609         return result;
610 }
611
612 static int acpi_battery_set_alarm(struct acpi_battery *battery)
613 {
614         acpi_status status = 0;
615
616         if (!acpi_battery_present(battery) ||
617             !test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags))
618                 return -ENODEV;
619
620         mutex_lock(&battery->lock);
621         status = acpi_execute_simple_method(battery->device->handle, "_BTP",
622                                             battery->alarm);
623         mutex_unlock(&battery->lock);
624
625         if (ACPI_FAILURE(status))
626                 return -ENODEV;
627
628         acpi_handle_debug(battery->device->handle, "Alarm set to %d\n",
629                           battery->alarm);
630
631         return 0;
632 }
633
634 static int acpi_battery_init_alarm(struct acpi_battery *battery)
635 {
636         /* See if alarms are supported, and if so, set default */
637         if (!acpi_has_method(battery->device->handle, "_BTP")) {
638                 clear_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags);
639                 return 0;
640         }
641         set_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags);
642         if (!battery->alarm)
643                 battery->alarm = battery->design_capacity_warning;
644         return acpi_battery_set_alarm(battery);
645 }
646
647 static ssize_t acpi_battery_alarm_show(struct device *dev,
648                                         struct device_attribute *attr,
649                                         char *buf)
650 {
651         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
652
653         return sprintf(buf, "%d\n", battery->alarm * 1000);
654 }
655
656 static ssize_t acpi_battery_alarm_store(struct device *dev,
657                                         struct device_attribute *attr,
658                                         const char *buf, size_t count)
659 {
660         unsigned long x;
661         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
662
663         if (sscanf(buf, "%lu\n", &x) == 1)
664                 battery->alarm = x/1000;
665         if (acpi_battery_present(battery))
666                 acpi_battery_set_alarm(battery);
667         return count;
668 }
669
670 static const struct device_attribute alarm_attr = {
671         .attr = {.name = "alarm", .mode = 0644},
672         .show = acpi_battery_alarm_show,
673         .store = acpi_battery_alarm_store,
674 };
675
676 /*
677  * The Battery Hooking API
678  *
679  * This API is used inside other drivers that need to expose
680  * platform-specific behaviour within the generic driver in a
681  * generic way.
682  *
683  */
684
685 static LIST_HEAD(acpi_battery_list);
686 static LIST_HEAD(battery_hook_list);
687 static DEFINE_MUTEX(hook_mutex);
688
689 static void __battery_hook_unregister(struct acpi_battery_hook *hook, int lock)
690 {
691         struct acpi_battery *battery;
692         /*
693          * In order to remove a hook, we first need to
694          * de-register all the batteries that are registered.
695          */
696         if (lock)
697                 mutex_lock(&hook_mutex);
698         list_for_each_entry(battery, &acpi_battery_list, list) {
699                 hook->remove_battery(battery->bat);
700         }
701         list_del(&hook->list);
702         if (lock)
703                 mutex_unlock(&hook_mutex);
704         pr_info("extension unregistered: %s\n", hook->name);
705 }
706
707 void battery_hook_unregister(struct acpi_battery_hook *hook)
708 {
709         __battery_hook_unregister(hook, 1);
710 }
711 EXPORT_SYMBOL_GPL(battery_hook_unregister);
712
713 void battery_hook_register(struct acpi_battery_hook *hook)
714 {
715         struct acpi_battery *battery;
716
717         mutex_lock(&hook_mutex);
718         INIT_LIST_HEAD(&hook->list);
719         list_add(&hook->list, &battery_hook_list);
720         /*
721          * Now that the driver is registered, we need
722          * to notify the hook that a battery is available
723          * for each battery, so that the driver may add
724          * its attributes.
725          */
726         list_for_each_entry(battery, &acpi_battery_list, list) {
727                 if (hook->add_battery(battery->bat)) {
728                         /*
729                          * If a add-battery returns non-zero,
730                          * the registration of the extension has failed,
731                          * and we will not add it to the list of loaded
732                          * hooks.
733                          */
734                         pr_err("extension failed to load: %s", hook->name);
735                         __battery_hook_unregister(hook, 0);
736                         goto end;
737                 }
738         }
739         pr_info("new extension: %s\n", hook->name);
740 end:
741         mutex_unlock(&hook_mutex);
742 }
743 EXPORT_SYMBOL_GPL(battery_hook_register);
744
745 /*
746  * This function gets called right after the battery sysfs
747  * attributes have been added, so that the drivers that
748  * define custom sysfs attributes can add their own.
749  */
750 static void battery_hook_add_battery(struct acpi_battery *battery)
751 {
752         struct acpi_battery_hook *hook_node, *tmp;
753
754         mutex_lock(&hook_mutex);
755         INIT_LIST_HEAD(&battery->list);
756         list_add(&battery->list, &acpi_battery_list);
757         /*
758          * Since we added a new battery to the list, we need to
759          * iterate over the hooks and call add_battery for each
760          * hook that was registered. This usually happens
761          * when a battery gets hotplugged or initialized
762          * during the battery module initialization.
763          */
764         list_for_each_entry_safe(hook_node, tmp, &battery_hook_list, list) {
765                 if (hook_node->add_battery(battery->bat)) {
766                         /*
767                          * The notification of the extensions has failed, to
768                          * prevent further errors we will unload the extension.
769                          */
770                         pr_err("error in extension, unloading: %s",
771                                         hook_node->name);
772                         __battery_hook_unregister(hook_node, 0);
773                 }
774         }
775         mutex_unlock(&hook_mutex);
776 }
777
778 static void battery_hook_remove_battery(struct acpi_battery *battery)
779 {
780         struct acpi_battery_hook *hook;
781
782         mutex_lock(&hook_mutex);
783         /*
784          * Before removing the hook, we need to remove all
785          * custom attributes from the battery.
786          */
787         list_for_each_entry(hook, &battery_hook_list, list) {
788                 hook->remove_battery(battery->bat);
789         }
790         /* Then, just remove the battery from the list */
791         list_del(&battery->list);
792         mutex_unlock(&hook_mutex);
793 }
794
795 static void __exit battery_hook_exit(void)
796 {
797         struct acpi_battery_hook *hook;
798         struct acpi_battery_hook *ptr;
799         /*
800          * At this point, the acpi_bus_unregister_driver()
801          * has called remove for all batteries. We just
802          * need to remove the hooks.
803          */
804         list_for_each_entry_safe(hook, ptr, &battery_hook_list, list) {
805                 __battery_hook_unregister(hook, 1);
806         }
807         mutex_destroy(&hook_mutex);
808 }
809
810 static int sysfs_add_battery(struct acpi_battery *battery)
811 {
812         struct power_supply_config psy_cfg = { .drv_data = battery, };
813         bool full_cap_broken = false;
814
815         if (!ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity) &&
816             !ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity))
817                 full_cap_broken = true;
818
819         if (battery->power_unit == ACPI_BATTERY_POWER_UNIT_MA) {
820                 if (full_cap_broken) {
821                         battery->bat_desc.properties =
822                             charge_battery_full_cap_broken_props;
823                         battery->bat_desc.num_properties =
824                             ARRAY_SIZE(charge_battery_full_cap_broken_props);
825                 } else {
826                         battery->bat_desc.properties = charge_battery_props;
827                         battery->bat_desc.num_properties =
828                             ARRAY_SIZE(charge_battery_props);
829                 }
830         } else {
831                 if (full_cap_broken) {
832                         battery->bat_desc.properties =
833                             energy_battery_full_cap_broken_props;
834                         battery->bat_desc.num_properties =
835                             ARRAY_SIZE(energy_battery_full_cap_broken_props);
836                 } else {
837                         battery->bat_desc.properties = energy_battery_props;
838                         battery->bat_desc.num_properties =
839                             ARRAY_SIZE(energy_battery_props);
840                 }
841         }
842
843         battery->bat_desc.name = acpi_device_bid(battery->device);
844         battery->bat_desc.type = POWER_SUPPLY_TYPE_BATTERY;
845         battery->bat_desc.get_property = acpi_battery_get_property;
846
847         battery->bat = power_supply_register_no_ws(&battery->device->dev,
848                                 &battery->bat_desc, &psy_cfg);
849
850         if (IS_ERR(battery->bat)) {
851                 int result = PTR_ERR(battery->bat);
852
853                 battery->bat = NULL;
854                 return result;
855         }
856         battery_hook_add_battery(battery);
857         return device_create_file(&battery->bat->dev, &alarm_attr);
858 }
859
860 static void sysfs_remove_battery(struct acpi_battery *battery)
861 {
862         mutex_lock(&battery->sysfs_lock);
863         if (!battery->bat) {
864                 mutex_unlock(&battery->sysfs_lock);
865                 return;
866         }
867         battery_hook_remove_battery(battery);
868         device_remove_file(&battery->bat->dev, &alarm_attr);
869         power_supply_unregister(battery->bat);
870         battery->bat = NULL;
871         mutex_unlock(&battery->sysfs_lock);
872 }
873
874 static void find_battery(const struct dmi_header *dm, void *private)
875 {
876         struct acpi_battery *battery = (struct acpi_battery *)private;
877         /* Note: the hardcoded offsets below have been extracted from
878          * the source code of dmidecode.
879          */
880         if (dm->type == DMI_ENTRY_PORTABLE_BATTERY && dm->length >= 8) {
881                 const u8 *dmi_data = (const u8 *)(dm + 1);
882                 int dmi_capacity = get_unaligned((const u16 *)(dmi_data + 6));
883
884                 if (dm->length >= 18)
885                         dmi_capacity *= dmi_data[17];
886                 if (battery->design_capacity * battery->design_voltage / 1000
887                     != dmi_capacity &&
888                     battery->design_capacity * 10 == dmi_capacity)
889                         set_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH,
890                                 &battery->flags);
891         }
892 }
893
894 /*
895  * According to the ACPI spec, some kinds of primary batteries can
896  * report percentage battery remaining capacity directly to OS.
897  * In this case, it reports the Last Full Charged Capacity == 100
898  * and BatteryPresentRate == 0xFFFFFFFF.
899  *
900  * Now we found some battery reports percentage remaining capacity
901  * even if it's rechargeable.
902  * https://bugzilla.kernel.org/show_bug.cgi?id=15979
903  *
904  * Handle this correctly so that they won't break userspace.
905  */
906 static void acpi_battery_quirks(struct acpi_battery *battery)
907 {
908         if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags))
909                 return;
910
911         if (battery->full_charge_capacity == 100 &&
912                 battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN &&
913                 battery->capacity_now >= 0 && battery->capacity_now <= 100) {
914                 set_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags);
915                 battery->full_charge_capacity = battery->design_capacity;
916                 battery->capacity_now = (battery->capacity_now *
917                                 battery->full_charge_capacity) / 100;
918         }
919
920         if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH, &battery->flags))
921                 return;
922
923         if (battery->power_unit && dmi_name_in_vendors("LENOVO")) {
924                 const char *s;
925
926                 s = dmi_get_system_info(DMI_PRODUCT_VERSION);
927                 if (s && !strncasecmp(s, "ThinkPad", 8)) {
928                         dmi_walk(find_battery, battery);
929                         if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH,
930                                      &battery->flags) &&
931                             battery->design_voltage) {
932                                 battery->design_capacity =
933                                     battery->design_capacity *
934                                     10000 / battery->design_voltage;
935                                 battery->full_charge_capacity =
936                                     battery->full_charge_capacity *
937                                     10000 / battery->design_voltage;
938                                 battery->design_capacity_warning =
939                                     battery->design_capacity_warning *
940                                     10000 / battery->design_voltage;
941                                 battery->capacity_now = battery->capacity_now *
942                                     10000 / battery->design_voltage;
943                         }
944                 }
945         }
946
947         if (test_bit(ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE, &battery->flags))
948                 return;
949
950         if (acpi_battery_is_degraded(battery) &&
951             battery->capacity_now > battery->full_charge_capacity) {
952                 set_bit(ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE, &battery->flags);
953                 battery->capacity_now = battery->full_charge_capacity;
954         }
955 }
956
957 static int acpi_battery_update(struct acpi_battery *battery, bool resume)
958 {
959         int result = acpi_battery_get_status(battery);
960
961         if (result)
962                 return result;
963
964         if (!acpi_battery_present(battery)) {
965                 sysfs_remove_battery(battery);
966                 battery->update_time = 0;
967                 return 0;
968         }
969
970         if (resume)
971                 return 0;
972
973         if (!battery->update_time) {
974                 result = acpi_battery_get_info(battery);
975                 if (result)
976                         return result;
977                 acpi_battery_init_alarm(battery);
978         }
979
980         result = acpi_battery_get_state(battery);
981         if (result)
982                 return result;
983         acpi_battery_quirks(battery);
984
985         if (!battery->bat) {
986                 result = sysfs_add_battery(battery);
987                 if (result)
988                         return result;
989         }
990
991         /*
992          * Wakeup the system if battery is critical low
993          * or lower than the alarm level
994          */
995         if ((battery->state & ACPI_BATTERY_STATE_CRITICAL) ||
996             (test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags) &&
997              (battery->capacity_now <= battery->alarm)))
998                 acpi_pm_wakeup_event(&battery->device->dev);
999
1000         return result;
1001 }
1002
1003 static void acpi_battery_refresh(struct acpi_battery *battery)
1004 {
1005         int power_unit;
1006
1007         if (!battery->bat)
1008                 return;
1009
1010         power_unit = battery->power_unit;
1011
1012         acpi_battery_get_info(battery);
1013
1014         if (power_unit == battery->power_unit)
1015                 return;
1016
1017         /* The battery has changed its reporting units. */
1018         sysfs_remove_battery(battery);
1019         sysfs_add_battery(battery);
1020 }
1021
1022 /* Driver Interface */
1023 static void acpi_battery_notify(struct acpi_device *device, u32 event)
1024 {
1025         struct acpi_battery *battery = acpi_driver_data(device);
1026         struct power_supply *old;
1027
1028         if (!battery)
1029                 return;
1030         old = battery->bat;
1031         /*
1032          * On Acer Aspire V5-573G notifications are sometimes triggered too
1033          * early. For example, when AC is unplugged and notification is
1034          * triggered, battery state is still reported as "Full", and changes to
1035          * "Discharging" only after short delay, without any notification.
1036          */
1037         if (battery_notification_delay_ms > 0)
1038                 msleep(battery_notification_delay_ms);
1039         if (event == ACPI_BATTERY_NOTIFY_INFO)
1040                 acpi_battery_refresh(battery);
1041         acpi_battery_update(battery, false);
1042         acpi_bus_generate_netlink_event(device->pnp.device_class,
1043                                         dev_name(&device->dev), event,
1044                                         acpi_battery_present(battery));
1045         acpi_notifier_call_chain(device, event, acpi_battery_present(battery));
1046         /* acpi_battery_update could remove power_supply object */
1047         if (old && battery->bat)
1048                 power_supply_changed(battery->bat);
1049 }
1050
1051 static int battery_notify(struct notifier_block *nb,
1052                                unsigned long mode, void *_unused)
1053 {
1054         struct acpi_battery *battery = container_of(nb, struct acpi_battery,
1055                                                     pm_nb);
1056         int result;
1057
1058         switch (mode) {
1059         case PM_POST_HIBERNATION:
1060         case PM_POST_SUSPEND:
1061                 if (!acpi_battery_present(battery))
1062                         return 0;
1063
1064                 if (battery->bat) {
1065                         acpi_battery_refresh(battery);
1066                 } else {
1067                         result = acpi_battery_get_info(battery);
1068                         if (result)
1069                                 return result;
1070
1071                         result = sysfs_add_battery(battery);
1072                         if (result)
1073                                 return result;
1074                 }
1075
1076                 acpi_battery_init_alarm(battery);
1077                 acpi_battery_get_state(battery);
1078                 break;
1079         }
1080
1081         return 0;
1082 }
1083
1084 static int __init
1085 battery_bix_broken_package_quirk(const struct dmi_system_id *d)
1086 {
1087         battery_bix_broken_package = 1;
1088         return 0;
1089 }
1090
1091 static int __init
1092 battery_notification_delay_quirk(const struct dmi_system_id *d)
1093 {
1094         battery_notification_delay_ms = 1000;
1095         return 0;
1096 }
1097
1098 static int __init
1099 battery_ac_is_broken_quirk(const struct dmi_system_id *d)
1100 {
1101         battery_ac_is_broken = 1;
1102         return 0;
1103 }
1104
1105 static const struct dmi_system_id bat_dmi_table[] __initconst = {
1106         {
1107                 /* NEC LZ750/LS */
1108                 .callback = battery_bix_broken_package_quirk,
1109                 .matches = {
1110                         DMI_MATCH(DMI_SYS_VENDOR, "NEC"),
1111                         DMI_MATCH(DMI_PRODUCT_NAME, "PC-LZ750LS"),
1112                 },
1113         },
1114         {
1115                 /* Acer Aspire V5-573G */
1116                 .callback = battery_notification_delay_quirk,
1117                 .matches = {
1118                         DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
1119                         DMI_MATCH(DMI_PRODUCT_NAME, "Aspire V5-573G"),
1120                 },
1121         },
1122         {
1123                 /* Point of View mobii wintab p800w */
1124                 .callback = battery_ac_is_broken_quirk,
1125                 .matches = {
1126                         DMI_MATCH(DMI_BOARD_VENDOR, "AMI Corporation"),
1127                         DMI_MATCH(DMI_BOARD_NAME, "Aptio CRB"),
1128                         DMI_MATCH(DMI_BIOS_VERSION, "3BAIR1013"),
1129                         /* Above matches are too generic, add bios-date match */
1130                         DMI_MATCH(DMI_BIOS_DATE, "08/22/2014"),
1131                 },
1132         },
1133         {
1134                 /* Microsoft Surface Go 3 */
1135                 .callback = battery_notification_delay_quirk,
1136                 .matches = {
1137                         DMI_MATCH(DMI_SYS_VENDOR, "Microsoft Corporation"),
1138                         DMI_MATCH(DMI_PRODUCT_NAME, "Surface Go 3"),
1139                 },
1140         },
1141         {},
1142 };
1143
1144 /*
1145  * Some machines'(E,G Lenovo Z480) ECs are not stable
1146  * during boot up and this causes battery driver fails to be
1147  * probed due to failure of getting battery information
1148  * from EC sometimes. After several retries, the operation
1149  * may work. So add retry code here and 20ms sleep between
1150  * every retries.
1151  */
1152 static int acpi_battery_update_retry(struct acpi_battery *battery)
1153 {
1154         int retry, ret;
1155
1156         for (retry = 5; retry; retry--) {
1157                 ret = acpi_battery_update(battery, false);
1158                 if (!ret)
1159                         break;
1160
1161                 msleep(20);
1162         }
1163         return ret;
1164 }
1165
1166 static int acpi_battery_add(struct acpi_device *device)
1167 {
1168         int result = 0;
1169         struct acpi_battery *battery = NULL;
1170
1171         if (!device)
1172                 return -EINVAL;
1173
1174         if (device->dep_unmet)
1175                 return -EPROBE_DEFER;
1176
1177         battery = kzalloc(sizeof(struct acpi_battery), GFP_KERNEL);
1178         if (!battery)
1179                 return -ENOMEM;
1180         battery->device = device;
1181         strcpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
1182         strcpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
1183         device->driver_data = battery;
1184         mutex_init(&battery->lock);
1185         mutex_init(&battery->sysfs_lock);
1186         if (acpi_has_method(battery->device->handle, "_BIX"))
1187                 set_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags);
1188
1189         result = acpi_battery_update_retry(battery);
1190         if (result)
1191                 goto fail;
1192
1193         pr_info("Slot [%s] (battery %s)\n", acpi_device_bid(device),
1194                 device->status.battery_present ? "present" : "absent");
1195
1196         battery->pm_nb.notifier_call = battery_notify;
1197         register_pm_notifier(&battery->pm_nb);
1198
1199         device_init_wakeup(&device->dev, 1);
1200
1201         return result;
1202
1203 fail:
1204         sysfs_remove_battery(battery);
1205         mutex_destroy(&battery->lock);
1206         mutex_destroy(&battery->sysfs_lock);
1207         kfree(battery);
1208         return result;
1209 }
1210
1211 static int acpi_battery_remove(struct acpi_device *device)
1212 {
1213         struct acpi_battery *battery = NULL;
1214
1215         if (!device || !acpi_driver_data(device))
1216                 return -EINVAL;
1217         device_init_wakeup(&device->dev, 0);
1218         battery = acpi_driver_data(device);
1219         unregister_pm_notifier(&battery->pm_nb);
1220         sysfs_remove_battery(battery);
1221         mutex_destroy(&battery->lock);
1222         mutex_destroy(&battery->sysfs_lock);
1223         kfree(battery);
1224         return 0;
1225 }
1226
1227 #ifdef CONFIG_PM_SLEEP
1228 /* this is needed to learn about changes made in suspended state */
1229 static int acpi_battery_resume(struct device *dev)
1230 {
1231         struct acpi_battery *battery;
1232
1233         if (!dev)
1234                 return -EINVAL;
1235
1236         battery = acpi_driver_data(to_acpi_device(dev));
1237         if (!battery)
1238                 return -EINVAL;
1239
1240         battery->update_time = 0;
1241         acpi_battery_update(battery, true);
1242         return 0;
1243 }
1244 #else
1245 #define acpi_battery_resume NULL
1246 #endif
1247
1248 static SIMPLE_DEV_PM_OPS(acpi_battery_pm, NULL, acpi_battery_resume);
1249
1250 static struct acpi_driver acpi_battery_driver = {
1251         .name = "battery",
1252         .class = ACPI_BATTERY_CLASS,
1253         .ids = battery_device_ids,
1254         .flags = ACPI_DRIVER_ALL_NOTIFY_EVENTS,
1255         .ops = {
1256                 .add = acpi_battery_add,
1257                 .remove = acpi_battery_remove,
1258                 .notify = acpi_battery_notify,
1259                 },
1260         .drv.pm = &acpi_battery_pm,
1261 };
1262
1263 static void __init acpi_battery_init_async(void *unused, async_cookie_t cookie)
1264 {
1265         int result;
1266
1267         if (acpi_quirk_skip_acpi_ac_and_battery())
1268                 return;
1269
1270         dmi_check_system(bat_dmi_table);
1271
1272         result = acpi_bus_register_driver(&acpi_battery_driver);
1273         battery_driver_registered = (result == 0);
1274 }
1275
1276 static int __init acpi_battery_init(void)
1277 {
1278         if (acpi_disabled)
1279                 return -ENODEV;
1280
1281         async_cookie = async_schedule(acpi_battery_init_async, NULL);
1282         return 0;
1283 }
1284
1285 static void __exit acpi_battery_exit(void)
1286 {
1287         async_synchronize_cookie(async_cookie + 1);
1288         if (battery_driver_registered) {
1289                 acpi_bus_unregister_driver(&acpi_battery_driver);
1290                 battery_hook_exit();
1291         }
1292 }
1293
1294 module_init(acpi_battery_init);
1295 module_exit(acpi_battery_exit);