xref: /openbmc/linux/drivers/acpi/battery.c (revision c832da79)
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);
1296