xref: /openbmc/linux/drivers/acpi/battery.c (revision 8931ddd8)
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 int battery_quirk_notcharging;
56 static unsigned int cache_time = 1000;
57 module_param(cache_time, uint, 0644);
58 MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
59 
60 static const struct acpi_device_id battery_device_ids[] = {
61 	{"PNP0C0A", 0},
62 	{"", 0},
63 };
64 
65 MODULE_DEVICE_TABLE(acpi, battery_device_ids);
66 
67 enum {
68 	ACPI_BATTERY_ALARM_PRESENT,
69 	ACPI_BATTERY_XINFO_PRESENT,
70 	ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY,
71 	/* On Lenovo Thinkpad models from 2010 and 2011, the power unit
72 	 * switches between mWh and mAh depending on whether the system
73 	 * is running on battery or not.  When mAh is the unit, most
74 	 * reported values are incorrect and need to be adjusted by
75 	 * 10000/design_voltage.  Verified on x201, t410, t410s, and x220.
76 	 * Pre-2010 and 2012 models appear to always report in mWh and
77 	 * are thus unaffected (tested with t42, t61, t500, x200, x300,
78 	 * and x230).  Also, in mid-2012 Lenovo issued a BIOS update for
79 	 *  the 2011 models that fixes the issue (tested on x220 with a
80 	 * post-1.29 BIOS), but as of Nov. 2012, no such update is
81 	 * available for the 2010 models.
82 	 */
83 	ACPI_BATTERY_QUIRK_THINKPAD_MAH,
84 	/* for batteries reporting current capacity with design capacity
85 	 * on a full charge, but showing degradation in full charge cap.
86 	 */
87 	ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE,
88 };
89 
90 struct acpi_battery {
91 	struct mutex lock;
92 	struct mutex sysfs_lock;
93 	struct power_supply *bat;
94 	struct power_supply_desc bat_desc;
95 	struct acpi_device *device;
96 	struct notifier_block pm_nb;
97 	struct list_head list;
98 	unsigned long update_time;
99 	int revision;
100 	int rate_now;
101 	int capacity_now;
102 	int voltage_now;
103 	int design_capacity;
104 	int full_charge_capacity;
105 	int technology;
106 	int design_voltage;
107 	int design_capacity_warning;
108 	int design_capacity_low;
109 	int cycle_count;
110 	int measurement_accuracy;
111 	int max_sampling_time;
112 	int min_sampling_time;
113 	int max_averaging_interval;
114 	int min_averaging_interval;
115 	int capacity_granularity_1;
116 	int capacity_granularity_2;
117 	int alarm;
118 	char model_number[32];
119 	char serial_number[32];
120 	char type[32];
121 	char oem_info[32];
122 	int state;
123 	int power_unit;
124 	unsigned long flags;
125 };
126 
127 #define to_acpi_battery(x) power_supply_get_drvdata(x)
128 
129 static inline int acpi_battery_present(struct acpi_battery *battery)
130 {
131 	return battery->device->status.battery_present;
132 }
133 
134 static int acpi_battery_technology(struct acpi_battery *battery)
135 {
136 	if (!strcasecmp("NiCd", battery->type))
137 		return POWER_SUPPLY_TECHNOLOGY_NiCd;
138 	if (!strcasecmp("NiMH", battery->type))
139 		return POWER_SUPPLY_TECHNOLOGY_NiMH;
140 	if (!strcasecmp("LION", battery->type))
141 		return POWER_SUPPLY_TECHNOLOGY_LION;
142 	if (!strncasecmp("LI-ION", battery->type, 6))
143 		return POWER_SUPPLY_TECHNOLOGY_LION;
144 	if (!strcasecmp("LiP", battery->type))
145 		return POWER_SUPPLY_TECHNOLOGY_LIPO;
146 	return POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
147 }
148 
149 static int acpi_battery_get_state(struct acpi_battery *battery);
150 
151 static int acpi_battery_is_charged(struct acpi_battery *battery)
152 {
153 	/* charging, discharging or critical low */
154 	if (battery->state != 0)
155 		return 0;
156 
157 	/* battery not reporting charge */
158 	if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN ||
159 	    battery->capacity_now == 0)
160 		return 0;
161 
162 	/* good batteries update full_charge as the batteries degrade */
163 	if (battery->full_charge_capacity == battery->capacity_now)
164 		return 1;
165 
166 	/* fallback to using design values for broken batteries */
167 	if (battery->design_capacity <= battery->capacity_now)
168 		return 1;
169 
170 	/* we don't do any sort of metric based on percentages */
171 	return 0;
172 }
173 
174 static bool acpi_battery_is_degraded(struct acpi_battery *battery)
175 {
176 	return ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity) &&
177 		ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity) &&
178 		battery->full_charge_capacity < battery->design_capacity;
179 }
180 
181 static int acpi_battery_handle_discharging(struct acpi_battery *battery)
182 {
183 	/*
184 	 * Some devices wrongly report discharging if the battery's charge level
185 	 * was above the device's start charging threshold atm the AC adapter
186 	 * was plugged in and the device thus did not start a new charge cycle.
187 	 */
188 	if ((battery_ac_is_broken || power_supply_is_system_supplied()) &&
189 	    battery->rate_now == 0)
190 		return POWER_SUPPLY_STATUS_NOT_CHARGING;
191 
192 	return POWER_SUPPLY_STATUS_DISCHARGING;
193 }
194 
195 static int acpi_battery_get_property(struct power_supply *psy,
196 				     enum power_supply_property psp,
197 				     union power_supply_propval *val)
198 {
199 	int full_capacity = ACPI_BATTERY_VALUE_UNKNOWN, ret = 0;
200 	struct acpi_battery *battery = to_acpi_battery(psy);
201 
202 	if (acpi_battery_present(battery)) {
203 		/* run battery update only if it is present */
204 		acpi_battery_get_state(battery);
205 	} else if (psp != POWER_SUPPLY_PROP_PRESENT)
206 		return -ENODEV;
207 	switch (psp) {
208 	case POWER_SUPPLY_PROP_STATUS:
209 		if (battery->state & ACPI_BATTERY_STATE_DISCHARGING)
210 			val->intval = acpi_battery_handle_discharging(battery);
211 		else if (battery->state & ACPI_BATTERY_STATE_CHARGING)
212 			val->intval = POWER_SUPPLY_STATUS_CHARGING;
213 		else if (acpi_battery_is_charged(battery))
214 			val->intval = POWER_SUPPLY_STATUS_FULL;
215 		else if (battery_quirk_notcharging)
216 			val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
217 		else
218 			val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
219 		break;
220 	case POWER_SUPPLY_PROP_PRESENT:
221 		val->intval = acpi_battery_present(battery);
222 		break;
223 	case POWER_SUPPLY_PROP_TECHNOLOGY:
224 		val->intval = acpi_battery_technology(battery);
225 		break;
226 	case POWER_SUPPLY_PROP_CYCLE_COUNT:
227 		val->intval = battery->cycle_count;
228 		break;
229 	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
230 		if (battery->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
231 			ret = -ENODEV;
232 		else
233 			val->intval = battery->design_voltage * 1000;
234 		break;
235 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
236 		if (battery->voltage_now == ACPI_BATTERY_VALUE_UNKNOWN)
237 			ret = -ENODEV;
238 		else
239 			val->intval = battery->voltage_now * 1000;
240 		break;
241 	case POWER_SUPPLY_PROP_CURRENT_NOW:
242 	case POWER_SUPPLY_PROP_POWER_NOW:
243 		if (battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN)
244 			ret = -ENODEV;
245 		else
246 			val->intval = battery->rate_now * 1000;
247 		break;
248 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
249 	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
250 		if (!ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity))
251 			ret = -ENODEV;
252 		else
253 			val->intval = battery->design_capacity * 1000;
254 		break;
255 	case POWER_SUPPLY_PROP_CHARGE_FULL:
256 	case POWER_SUPPLY_PROP_ENERGY_FULL:
257 		if (!ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity))
258 			ret = -ENODEV;
259 		else
260 			val->intval = battery->full_charge_capacity * 1000;
261 		break;
262 	case POWER_SUPPLY_PROP_CHARGE_NOW:
263 	case POWER_SUPPLY_PROP_ENERGY_NOW:
264 		if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN)
265 			ret = -ENODEV;
266 		else
267 			val->intval = battery->capacity_now * 1000;
268 		break;
269 	case POWER_SUPPLY_PROP_CAPACITY:
270 		if (ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity))
271 			full_capacity = battery->full_charge_capacity;
272 		else if (ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity))
273 			full_capacity = battery->design_capacity;
274 
275 		if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN ||
276 		    full_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
277 			ret = -ENODEV;
278 		else
279 			val->intval = battery->capacity_now * 100/
280 					full_capacity;
281 		break;
282 	case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
283 		if (battery->state & ACPI_BATTERY_STATE_CRITICAL)
284 			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
285 		else if (test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags) &&
286 			(battery->capacity_now <= battery->alarm))
287 			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
288 		else if (acpi_battery_is_charged(battery))
289 			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
290 		else
291 			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
292 		break;
293 	case POWER_SUPPLY_PROP_MODEL_NAME:
294 		val->strval = battery->model_number;
295 		break;
296 	case POWER_SUPPLY_PROP_MANUFACTURER:
297 		val->strval = battery->oem_info;
298 		break;
299 	case POWER_SUPPLY_PROP_SERIAL_NUMBER:
300 		val->strval = battery->serial_number;
301 		break;
302 	default:
303 		ret = -EINVAL;
304 	}
305 	return ret;
306 }
307 
308 static enum power_supply_property charge_battery_props[] = {
309 	POWER_SUPPLY_PROP_STATUS,
310 	POWER_SUPPLY_PROP_PRESENT,
311 	POWER_SUPPLY_PROP_TECHNOLOGY,
312 	POWER_SUPPLY_PROP_CYCLE_COUNT,
313 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
314 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
315 	POWER_SUPPLY_PROP_CURRENT_NOW,
316 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
317 	POWER_SUPPLY_PROP_CHARGE_FULL,
318 	POWER_SUPPLY_PROP_CHARGE_NOW,
319 	POWER_SUPPLY_PROP_CAPACITY,
320 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
321 	POWER_SUPPLY_PROP_MODEL_NAME,
322 	POWER_SUPPLY_PROP_MANUFACTURER,
323 	POWER_SUPPLY_PROP_SERIAL_NUMBER,
324 };
325 
326 static enum power_supply_property charge_battery_full_cap_broken_props[] = {
327 	POWER_SUPPLY_PROP_STATUS,
328 	POWER_SUPPLY_PROP_PRESENT,
329 	POWER_SUPPLY_PROP_TECHNOLOGY,
330 	POWER_SUPPLY_PROP_CYCLE_COUNT,
331 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
332 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
333 	POWER_SUPPLY_PROP_CURRENT_NOW,
334 	POWER_SUPPLY_PROP_CHARGE_NOW,
335 	POWER_SUPPLY_PROP_MODEL_NAME,
336 	POWER_SUPPLY_PROP_MANUFACTURER,
337 	POWER_SUPPLY_PROP_SERIAL_NUMBER,
338 };
339 
340 static enum power_supply_property energy_battery_props[] = {
341 	POWER_SUPPLY_PROP_STATUS,
342 	POWER_SUPPLY_PROP_PRESENT,
343 	POWER_SUPPLY_PROP_TECHNOLOGY,
344 	POWER_SUPPLY_PROP_CYCLE_COUNT,
345 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
346 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
347 	POWER_SUPPLY_PROP_POWER_NOW,
348 	POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
349 	POWER_SUPPLY_PROP_ENERGY_FULL,
350 	POWER_SUPPLY_PROP_ENERGY_NOW,
351 	POWER_SUPPLY_PROP_CAPACITY,
352 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
353 	POWER_SUPPLY_PROP_MODEL_NAME,
354 	POWER_SUPPLY_PROP_MANUFACTURER,
355 	POWER_SUPPLY_PROP_SERIAL_NUMBER,
356 };
357 
358 static enum power_supply_property energy_battery_full_cap_broken_props[] = {
359 	POWER_SUPPLY_PROP_STATUS,
360 	POWER_SUPPLY_PROP_PRESENT,
361 	POWER_SUPPLY_PROP_TECHNOLOGY,
362 	POWER_SUPPLY_PROP_CYCLE_COUNT,
363 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
364 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
365 	POWER_SUPPLY_PROP_POWER_NOW,
366 	POWER_SUPPLY_PROP_ENERGY_NOW,
367 	POWER_SUPPLY_PROP_MODEL_NAME,
368 	POWER_SUPPLY_PROP_MANUFACTURER,
369 	POWER_SUPPLY_PROP_SERIAL_NUMBER,
370 };
371 
372 /* Battery Management */
373 struct acpi_offsets {
374 	size_t offset;		/* offset inside struct acpi_sbs_battery */
375 	u8 mode;		/* int or string? */
376 };
377 
378 static const struct acpi_offsets state_offsets[] = {
379 	{offsetof(struct acpi_battery, state), 0},
380 	{offsetof(struct acpi_battery, rate_now), 0},
381 	{offsetof(struct acpi_battery, capacity_now), 0},
382 	{offsetof(struct acpi_battery, voltage_now), 0},
383 };
384 
385 static const struct acpi_offsets info_offsets[] = {
386 	{offsetof(struct acpi_battery, power_unit), 0},
387 	{offsetof(struct acpi_battery, design_capacity), 0},
388 	{offsetof(struct acpi_battery, full_charge_capacity), 0},
389 	{offsetof(struct acpi_battery, technology), 0},
390 	{offsetof(struct acpi_battery, design_voltage), 0},
391 	{offsetof(struct acpi_battery, design_capacity_warning), 0},
392 	{offsetof(struct acpi_battery, design_capacity_low), 0},
393 	{offsetof(struct acpi_battery, capacity_granularity_1), 0},
394 	{offsetof(struct acpi_battery, capacity_granularity_2), 0},
395 	{offsetof(struct acpi_battery, model_number), 1},
396 	{offsetof(struct acpi_battery, serial_number), 1},
397 	{offsetof(struct acpi_battery, type), 1},
398 	{offsetof(struct acpi_battery, oem_info), 1},
399 };
400 
401 static const struct acpi_offsets extended_info_offsets[] = {
402 	{offsetof(struct acpi_battery, revision), 0},
403 	{offsetof(struct acpi_battery, power_unit), 0},
404 	{offsetof(struct acpi_battery, design_capacity), 0},
405 	{offsetof(struct acpi_battery, full_charge_capacity), 0},
406 	{offsetof(struct acpi_battery, technology), 0},
407 	{offsetof(struct acpi_battery, design_voltage), 0},
408 	{offsetof(struct acpi_battery, design_capacity_warning), 0},
409 	{offsetof(struct acpi_battery, design_capacity_low), 0},
410 	{offsetof(struct acpi_battery, cycle_count), 0},
411 	{offsetof(struct acpi_battery, measurement_accuracy), 0},
412 	{offsetof(struct acpi_battery, max_sampling_time), 0},
413 	{offsetof(struct acpi_battery, min_sampling_time), 0},
414 	{offsetof(struct acpi_battery, max_averaging_interval), 0},
415 	{offsetof(struct acpi_battery, min_averaging_interval), 0},
416 	{offsetof(struct acpi_battery, capacity_granularity_1), 0},
417 	{offsetof(struct acpi_battery, capacity_granularity_2), 0},
418 	{offsetof(struct acpi_battery, model_number), 1},
419 	{offsetof(struct acpi_battery, serial_number), 1},
420 	{offsetof(struct acpi_battery, type), 1},
421 	{offsetof(struct acpi_battery, oem_info), 1},
422 };
423 
424 static int extract_package(struct acpi_battery *battery,
425 			   union acpi_object *package,
426 			   const struct acpi_offsets *offsets, int num)
427 {
428 	int i;
429 	union acpi_object *element;
430 
431 	if (package->type != ACPI_TYPE_PACKAGE)
432 		return -EFAULT;
433 	for (i = 0; i < num; ++i) {
434 		if (package->package.count <= i)
435 			return -EFAULT;
436 		element = &package->package.elements[i];
437 		if (offsets[i].mode) {
438 			u8 *ptr = (u8 *)battery + offsets[i].offset;
439 
440 			if (element->type == ACPI_TYPE_STRING ||
441 			    element->type == ACPI_TYPE_BUFFER)
442 				strncpy(ptr, element->string.pointer, 32);
443 			else if (element->type == ACPI_TYPE_INTEGER) {
444 				strncpy(ptr, (u8 *)&element->integer.value,
445 					sizeof(u64));
446 				ptr[sizeof(u64)] = 0;
447 			} else
448 				*ptr = 0; /* don't have value */
449 		} else {
450 			int *x = (int *)((u8 *)battery + offsets[i].offset);
451 			*x = (element->type == ACPI_TYPE_INTEGER) ?
452 				element->integer.value : -1;
453 		}
454 	}
455 	return 0;
456 }
457 
458 static int acpi_battery_get_status(struct acpi_battery *battery)
459 {
460 	if (acpi_bus_get_status(battery->device)) {
461 		acpi_handle_info(battery->device->handle,
462 				 "_STA evaluation failed\n");
463 		return -ENODEV;
464 	}
465 	return 0;
466 }
467 
468 
469 static int extract_battery_info(const int use_bix,
470 			 struct acpi_battery *battery,
471 			 const struct acpi_buffer *buffer)
472 {
473 	int result = -EFAULT;
474 
475 	if (use_bix && battery_bix_broken_package)
476 		result = extract_package(battery, buffer->pointer,
477 				extended_info_offsets + 1,
478 				ARRAY_SIZE(extended_info_offsets) - 1);
479 	else if (use_bix)
480 		result = extract_package(battery, buffer->pointer,
481 				extended_info_offsets,
482 				ARRAY_SIZE(extended_info_offsets));
483 	else
484 		result = extract_package(battery, buffer->pointer,
485 				info_offsets, ARRAY_SIZE(info_offsets));
486 	if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags))
487 		battery->full_charge_capacity = battery->design_capacity;
488 	if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH, &battery->flags) &&
489 	    battery->power_unit && battery->design_voltage) {
490 		battery->design_capacity = battery->design_capacity *
491 		    10000 / battery->design_voltage;
492 		battery->full_charge_capacity = battery->full_charge_capacity *
493 		    10000 / battery->design_voltage;
494 		battery->design_capacity_warning =
495 		    battery->design_capacity_warning *
496 		    10000 / battery->design_voltage;
497 		/* Curiously, design_capacity_low, unlike the rest of them,
498 		 *  is correct.
499 		 */
500 		/* capacity_granularity_* equal 1 on the systems tested, so
501 		 * it's impossible to tell if they would need an adjustment
502 		 * or not if their values were higher.
503 		 */
504 	}
505 	if (test_bit(ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE, &battery->flags) &&
506 	    battery->capacity_now > battery->full_charge_capacity)
507 		battery->capacity_now = battery->full_charge_capacity;
508 
509 	return result;
510 }
511 
512 static int acpi_battery_get_info(struct acpi_battery *battery)
513 {
514 	const int xinfo = test_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags);
515 	int use_bix;
516 	int result = -ENODEV;
517 
518 	if (!acpi_battery_present(battery))
519 		return 0;
520 
521 
522 	for (use_bix = xinfo ? 1 : 0; use_bix >= 0; use_bix--) {
523 		struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
524 		acpi_status status = AE_ERROR;
525 
526 		mutex_lock(&battery->lock);
527 		status = acpi_evaluate_object(battery->device->handle,
528 					      use_bix ? "_BIX":"_BIF",
529 					      NULL, &buffer);
530 		mutex_unlock(&battery->lock);
531 
532 		if (ACPI_FAILURE(status)) {
533 			acpi_handle_info(battery->device->handle,
534 					 "%s evaluation failed: %s\n",
535 					 use_bix ? "_BIX":"_BIF",
536 					 acpi_format_exception(status));
537 		} else {
538 			result = extract_battery_info(use_bix,
539 						      battery,
540 						      &buffer);
541 
542 			kfree(buffer.pointer);
543 			break;
544 		}
545 	}
546 
547 	if (!result && !use_bix && xinfo)
548 		pr_warn(FW_BUG "The _BIX method is broken, using _BIF.\n");
549 
550 	return result;
551 }
552 
553 static int acpi_battery_get_state(struct acpi_battery *battery)
554 {
555 	int result = 0;
556 	acpi_status status = 0;
557 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
558 
559 	if (!acpi_battery_present(battery))
560 		return 0;
561 
562 	if (battery->update_time &&
563 	    time_before(jiffies, battery->update_time +
564 			msecs_to_jiffies(cache_time)))
565 		return 0;
566 
567 	mutex_lock(&battery->lock);
568 	status = acpi_evaluate_object(battery->device->handle, "_BST",
569 				      NULL, &buffer);
570 	mutex_unlock(&battery->lock);
571 
572 	if (ACPI_FAILURE(status)) {
573 		acpi_handle_info(battery->device->handle,
574 				 "_BST evaluation failed: %s",
575 				 acpi_format_exception(status));
576 		return -ENODEV;
577 	}
578 
579 	result = extract_package(battery, buffer.pointer,
580 				 state_offsets, ARRAY_SIZE(state_offsets));
581 	battery->update_time = jiffies;
582 	kfree(buffer.pointer);
583 
584 	/* For buggy DSDTs that report negative 16-bit values for either
585 	 * charging or discharging current and/or report 0 as 65536
586 	 * due to bad math.
587 	 */
588 	if (battery->power_unit == ACPI_BATTERY_POWER_UNIT_MA &&
589 		battery->rate_now != ACPI_BATTERY_VALUE_UNKNOWN &&
590 		(s16)(battery->rate_now) < 0) {
591 		battery->rate_now = abs((s16)battery->rate_now);
592 		pr_warn_once(FW_BUG "(dis)charge rate invalid.\n");
593 	}
594 
595 	if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags)
596 	    && battery->capacity_now >= 0 && battery->capacity_now <= 100)
597 		battery->capacity_now = (battery->capacity_now *
598 				battery->full_charge_capacity) / 100;
599 	if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH, &battery->flags) &&
600 	    battery->power_unit && battery->design_voltage) {
601 		battery->capacity_now = battery->capacity_now *
602 		    10000 / battery->design_voltage;
603 	}
604 	if (test_bit(ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE, &battery->flags) &&
605 	    battery->capacity_now > battery->full_charge_capacity)
606 		battery->capacity_now = battery->full_charge_capacity;
607 
608 	return result;
609 }
610 
611 static int acpi_battery_set_alarm(struct acpi_battery *battery)
612 {
613 	acpi_status status = 0;
614 
615 	if (!acpi_battery_present(battery) ||
616 	    !test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags))
617 		return -ENODEV;
618 
619 	mutex_lock(&battery->lock);
620 	status = acpi_execute_simple_method(battery->device->handle, "_BTP",
621 					    battery->alarm);
622 	mutex_unlock(&battery->lock);
623 
624 	if (ACPI_FAILURE(status))
625 		return -ENODEV;
626 
627 	acpi_handle_debug(battery->device->handle, "Alarm set to %d\n",
628 			  battery->alarm);
629 
630 	return 0;
631 }
632 
633 static int acpi_battery_init_alarm(struct acpi_battery *battery)
634 {
635 	/* See if alarms are supported, and if so, set default */
636 	if (!acpi_has_method(battery->device->handle, "_BTP")) {
637 		clear_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags);
638 		return 0;
639 	}
640 	set_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags);
641 	if (!battery->alarm)
642 		battery->alarm = battery->design_capacity_warning;
643 	return acpi_battery_set_alarm(battery);
644 }
645 
646 static ssize_t acpi_battery_alarm_show(struct device *dev,
647 					struct device_attribute *attr,
648 					char *buf)
649 {
650 	struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
651 
652 	return sprintf(buf, "%d\n", battery->alarm * 1000);
653 }
654 
655 static ssize_t acpi_battery_alarm_store(struct device *dev,
656 					struct device_attribute *attr,
657 					const char *buf, size_t count)
658 {
659 	unsigned long x;
660 	struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
661 
662 	if (sscanf(buf, "%lu\n", &x) == 1)
663 		battery->alarm = x/1000;
664 	if (acpi_battery_present(battery))
665 		acpi_battery_set_alarm(battery);
666 	return count;
667 }
668 
669 static const struct device_attribute alarm_attr = {
670 	.attr = {.name = "alarm", .mode = 0644},
671 	.show = acpi_battery_alarm_show,
672 	.store = acpi_battery_alarm_store,
673 };
674 
675 /*
676  * The Battery Hooking API
677  *
678  * This API is used inside other drivers that need to expose
679  * platform-specific behaviour within the generic driver in a
680  * generic way.
681  *
682  */
683 
684 static LIST_HEAD(acpi_battery_list);
685 static LIST_HEAD(battery_hook_list);
686 static DEFINE_MUTEX(hook_mutex);
687 
688 static void __battery_hook_unregister(struct acpi_battery_hook *hook, int lock)
689 {
690 	struct acpi_battery *battery;
691 	/*
692 	 * In order to remove a hook, we first need to
693 	 * de-register all the batteries that are registered.
694 	 */
695 	if (lock)
696 		mutex_lock(&hook_mutex);
697 	list_for_each_entry(battery, &acpi_battery_list, list) {
698 		hook->remove_battery(battery->bat);
699 	}
700 	list_del(&hook->list);
701 	if (lock)
702 		mutex_unlock(&hook_mutex);
703 	pr_info("extension unregistered: %s\n", hook->name);
704 }
705 
706 void battery_hook_unregister(struct acpi_battery_hook *hook)
707 {
708 	__battery_hook_unregister(hook, 1);
709 }
710 EXPORT_SYMBOL_GPL(battery_hook_unregister);
711 
712 void battery_hook_register(struct acpi_battery_hook *hook)
713 {
714 	struct acpi_battery *battery;
715 
716 	mutex_lock(&hook_mutex);
717 	INIT_LIST_HEAD(&hook->list);
718 	list_add(&hook->list, &battery_hook_list);
719 	/*
720 	 * Now that the driver is registered, we need
721 	 * to notify the hook that a battery is available
722 	 * for each battery, so that the driver may add
723 	 * its attributes.
724 	 */
725 	list_for_each_entry(battery, &acpi_battery_list, list) {
726 		if (hook->add_battery(battery->bat)) {
727 			/*
728 			 * If a add-battery returns non-zero,
729 			 * the registration of the extension has failed,
730 			 * and we will not add it to the list of loaded
731 			 * hooks.
732 			 */
733 			pr_err("extension failed to load: %s", hook->name);
734 			__battery_hook_unregister(hook, 0);
735 			goto end;
736 		}
737 	}
738 	pr_info("new extension: %s\n", hook->name);
739 end:
740 	mutex_unlock(&hook_mutex);
741 }
742 EXPORT_SYMBOL_GPL(battery_hook_register);
743 
744 /*
745  * This function gets called right after the battery sysfs
746  * attributes have been added, so that the drivers that
747  * define custom sysfs attributes can add their own.
748  */
749 static void battery_hook_add_battery(struct acpi_battery *battery)
750 {
751 	struct acpi_battery_hook *hook_node, *tmp;
752 
753 	mutex_lock(&hook_mutex);
754 	INIT_LIST_HEAD(&battery->list);
755 	list_add(&battery->list, &acpi_battery_list);
756 	/*
757 	 * Since we added a new battery to the list, we need to
758 	 * iterate over the hooks and call add_battery for each
759 	 * hook that was registered. This usually happens
760 	 * when a battery gets hotplugged or initialized
761 	 * during the battery module initialization.
762 	 */
763 	list_for_each_entry_safe(hook_node, tmp, &battery_hook_list, list) {
764 		if (hook_node->add_battery(battery->bat)) {
765 			/*
766 			 * The notification of the extensions has failed, to
767 			 * prevent further errors we will unload the extension.
768 			 */
769 			pr_err("error in extension, unloading: %s",
770 					hook_node->name);
771 			__battery_hook_unregister(hook_node, 0);
772 		}
773 	}
774 	mutex_unlock(&hook_mutex);
775 }
776 
777 static void battery_hook_remove_battery(struct acpi_battery *battery)
778 {
779 	struct acpi_battery_hook *hook;
780 
781 	mutex_lock(&hook_mutex);
782 	/*
783 	 * Before removing the hook, we need to remove all
784 	 * custom attributes from the battery.
785 	 */
786 	list_for_each_entry(hook, &battery_hook_list, list) {
787 		hook->remove_battery(battery->bat);
788 	}
789 	/* Then, just remove the battery from the list */
790 	list_del(&battery->list);
791 	mutex_unlock(&hook_mutex);
792 }
793 
794 static void __exit battery_hook_exit(void)
795 {
796 	struct acpi_battery_hook *hook;
797 	struct acpi_battery_hook *ptr;
798 	/*
799 	 * At this point, the acpi_bus_unregister_driver()
800 	 * has called remove for all batteries. We just
801 	 * need to remove the hooks.
802 	 */
803 	list_for_each_entry_safe(hook, ptr, &battery_hook_list, list) {
804 		__battery_hook_unregister(hook, 1);
805 	}
806 	mutex_destroy(&hook_mutex);
807 }
808 
809 static int sysfs_add_battery(struct acpi_battery *battery)
810 {
811 	struct power_supply_config psy_cfg = { .drv_data = battery, };
812 	bool full_cap_broken = false;
813 
814 	if (!ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity) &&
815 	    !ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity))
816 		full_cap_broken = true;
817 
818 	if (battery->power_unit == ACPI_BATTERY_POWER_UNIT_MA) {
819 		if (full_cap_broken) {
820 			battery->bat_desc.properties =
821 			    charge_battery_full_cap_broken_props;
822 			battery->bat_desc.num_properties =
823 			    ARRAY_SIZE(charge_battery_full_cap_broken_props);
824 		} else {
825 			battery->bat_desc.properties = charge_battery_props;
826 			battery->bat_desc.num_properties =
827 			    ARRAY_SIZE(charge_battery_props);
828 		}
829 	} else {
830 		if (full_cap_broken) {
831 			battery->bat_desc.properties =
832 			    energy_battery_full_cap_broken_props;
833 			battery->bat_desc.num_properties =
834 			    ARRAY_SIZE(energy_battery_full_cap_broken_props);
835 		} else {
836 			battery->bat_desc.properties = energy_battery_props;
837 			battery->bat_desc.num_properties =
838 			    ARRAY_SIZE(energy_battery_props);
839 		}
840 	}
841 
842 	battery->bat_desc.name = acpi_device_bid(battery->device);
843 	battery->bat_desc.type = POWER_SUPPLY_TYPE_BATTERY;
844 	battery->bat_desc.get_property = acpi_battery_get_property;
845 
846 	battery->bat = power_supply_register_no_ws(&battery->device->dev,
847 				&battery->bat_desc, &psy_cfg);
848 
849 	if (IS_ERR(battery->bat)) {
850 		int result = PTR_ERR(battery->bat);
851 
852 		battery->bat = NULL;
853 		return result;
854 	}
855 	battery_hook_add_battery(battery);
856 	return device_create_file(&battery->bat->dev, &alarm_attr);
857 }
858 
859 static void sysfs_remove_battery(struct acpi_battery *battery)
860 {
861 	mutex_lock(&battery->sysfs_lock);
862 	if (!battery->bat) {
863 		mutex_unlock(&battery->sysfs_lock);
864 		return;
865 	}
866 	battery_hook_remove_battery(battery);
867 	device_remove_file(&battery->bat->dev, &alarm_attr);
868 	power_supply_unregister(battery->bat);
869 	battery->bat = NULL;
870 	mutex_unlock(&battery->sysfs_lock);
871 }
872 
873 static void find_battery(const struct dmi_header *dm, void *private)
874 {
875 	struct acpi_battery *battery = (struct acpi_battery *)private;
876 	/* Note: the hardcoded offsets below have been extracted from
877 	 * the source code of dmidecode.
878 	 */
879 	if (dm->type == DMI_ENTRY_PORTABLE_BATTERY && dm->length >= 8) {
880 		const u8 *dmi_data = (const u8 *)(dm + 1);
881 		int dmi_capacity = get_unaligned((const u16 *)(dmi_data + 6));
882 
883 		if (dm->length >= 18)
884 			dmi_capacity *= dmi_data[17];
885 		if (battery->design_capacity * battery->design_voltage / 1000
886 		    != dmi_capacity &&
887 		    battery->design_capacity * 10 == dmi_capacity)
888 			set_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH,
889 				&battery->flags);
890 	}
891 }
892 
893 /*
894  * According to the ACPI spec, some kinds of primary batteries can
895  * report percentage battery remaining capacity directly to OS.
896  * In this case, it reports the Last Full Charged Capacity == 100
897  * and BatteryPresentRate == 0xFFFFFFFF.
898  *
899  * Now we found some battery reports percentage remaining capacity
900  * even if it's rechargeable.
901  * https://bugzilla.kernel.org/show_bug.cgi?id=15979
902  *
903  * Handle this correctly so that they won't break userspace.
904  */
905 static void acpi_battery_quirks(struct acpi_battery *battery)
906 {
907 	if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags))
908 		return;
909 
910 	if (battery->full_charge_capacity == 100 &&
911 		battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN &&
912 		battery->capacity_now >= 0 && battery->capacity_now <= 100) {
913 		set_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags);
914 		battery->full_charge_capacity = battery->design_capacity;
915 		battery->capacity_now = (battery->capacity_now *
916 				battery->full_charge_capacity) / 100;
917 	}
918 
919 	if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH, &battery->flags))
920 		return;
921 
922 	if (battery->power_unit && dmi_name_in_vendors("LENOVO")) {
923 		const char *s;
924 
925 		s = dmi_get_system_info(DMI_PRODUCT_VERSION);
926 		if (s && !strncasecmp(s, "ThinkPad", 8)) {
927 			dmi_walk(find_battery, battery);
928 			if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH,
929 				     &battery->flags) &&
930 			    battery->design_voltage) {
931 				battery->design_capacity =
932 				    battery->design_capacity *
933 				    10000 / battery->design_voltage;
934 				battery->full_charge_capacity =
935 				    battery->full_charge_capacity *
936 				    10000 / battery->design_voltage;
937 				battery->design_capacity_warning =
938 				    battery->design_capacity_warning *
939 				    10000 / battery->design_voltage;
940 				battery->capacity_now = battery->capacity_now *
941 				    10000 / battery->design_voltage;
942 			}
943 		}
944 	}
945 
946 	if (test_bit(ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE, &battery->flags))
947 		return;
948 
949 	if (acpi_battery_is_degraded(battery) &&
950 	    battery->capacity_now > battery->full_charge_capacity) {
951 		set_bit(ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE, &battery->flags);
952 		battery->capacity_now = battery->full_charge_capacity;
953 	}
954 }
955 
956 static int acpi_battery_update(struct acpi_battery *battery, bool resume)
957 {
958 	int result = acpi_battery_get_status(battery);
959 
960 	if (result)
961 		return result;
962 
963 	if (!acpi_battery_present(battery)) {
964 		sysfs_remove_battery(battery);
965 		battery->update_time = 0;
966 		return 0;
967 	}
968 
969 	if (resume)
970 		return 0;
971 
972 	if (!battery->update_time) {
973 		result = acpi_battery_get_info(battery);
974 		if (result)
975 			return result;
976 		acpi_battery_init_alarm(battery);
977 	}
978 
979 	result = acpi_battery_get_state(battery);
980 	if (result)
981 		return result;
982 	acpi_battery_quirks(battery);
983 
984 	if (!battery->bat) {
985 		result = sysfs_add_battery(battery);
986 		if (result)
987 			return result;
988 	}
989 
990 	/*
991 	 * Wakeup the system if battery is critical low
992 	 * or lower than the alarm level
993 	 */
994 	if ((battery->state & ACPI_BATTERY_STATE_CRITICAL) ||
995 	    (test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags) &&
996 	     (battery->capacity_now <= battery->alarm)))
997 		acpi_pm_wakeup_event(&battery->device->dev);
998 
999 	return result;
1000 }
1001 
1002 static void acpi_battery_refresh(struct acpi_battery *battery)
1003 {
1004 	int power_unit;
1005 
1006 	if (!battery->bat)
1007 		return;
1008 
1009 	power_unit = battery->power_unit;
1010 
1011 	acpi_battery_get_info(battery);
1012 
1013 	if (power_unit == battery->power_unit)
1014 		return;
1015 
1016 	/* The battery has changed its reporting units. */
1017 	sysfs_remove_battery(battery);
1018 	sysfs_add_battery(battery);
1019 }
1020 
1021 /* Driver Interface */
1022 static void acpi_battery_notify(struct acpi_device *device, u32 event)
1023 {
1024 	struct acpi_battery *battery = acpi_driver_data(device);
1025 	struct power_supply *old;
1026 
1027 	if (!battery)
1028 		return;
1029 	old = battery->bat;
1030 	/*
1031 	 * On Acer Aspire V5-573G notifications are sometimes triggered too
1032 	 * early. For example, when AC is unplugged and notification is
1033 	 * triggered, battery state is still reported as "Full", and changes to
1034 	 * "Discharging" only after short delay, without any notification.
1035 	 */
1036 	if (battery_notification_delay_ms > 0)
1037 		msleep(battery_notification_delay_ms);
1038 	if (event == ACPI_BATTERY_NOTIFY_INFO)
1039 		acpi_battery_refresh(battery);
1040 	acpi_battery_update(battery, false);
1041 	acpi_bus_generate_netlink_event(device->pnp.device_class,
1042 					dev_name(&device->dev), event,
1043 					acpi_battery_present(battery));
1044 	acpi_notifier_call_chain(device, event, acpi_battery_present(battery));
1045 	/* acpi_battery_update could remove power_supply object */
1046 	if (old && battery->bat)
1047 		power_supply_changed(battery->bat);
1048 }
1049 
1050 static int battery_notify(struct notifier_block *nb,
1051 			       unsigned long mode, void *_unused)
1052 {
1053 	struct acpi_battery *battery = container_of(nb, struct acpi_battery,
1054 						    pm_nb);
1055 	int result;
1056 
1057 	switch (mode) {
1058 	case PM_POST_HIBERNATION:
1059 	case PM_POST_SUSPEND:
1060 		if (!acpi_battery_present(battery))
1061 			return 0;
1062 
1063 		if (battery->bat) {
1064 			acpi_battery_refresh(battery);
1065 		} else {
1066 			result = acpi_battery_get_info(battery);
1067 			if (result)
1068 				return result;
1069 
1070 			result = sysfs_add_battery(battery);
1071 			if (result)
1072 				return result;
1073 		}
1074 
1075 		acpi_battery_init_alarm(battery);
1076 		acpi_battery_get_state(battery);
1077 		break;
1078 	}
1079 
1080 	return 0;
1081 }
1082 
1083 static int __init
1084 battery_bix_broken_package_quirk(const struct dmi_system_id *d)
1085 {
1086 	battery_bix_broken_package = 1;
1087 	return 0;
1088 }
1089 
1090 static int __init
1091 battery_notification_delay_quirk(const struct dmi_system_id *d)
1092 {
1093 	battery_notification_delay_ms = 1000;
1094 	return 0;
1095 }
1096 
1097 static int __init
1098 battery_ac_is_broken_quirk(const struct dmi_system_id *d)
1099 {
1100 	battery_ac_is_broken = 1;
1101 	return 0;
1102 }
1103 
1104 static int __init battery_quirk_not_charging(const struct dmi_system_id *d)
1105 {
1106 	battery_quirk_notcharging = 1;
1107 	return 0;
1108 }
1109 
1110 static const struct dmi_system_id bat_dmi_table[] __initconst = {
1111 	{
1112 		/* NEC LZ750/LS */
1113 		.callback = battery_bix_broken_package_quirk,
1114 		.matches = {
1115 			DMI_MATCH(DMI_SYS_VENDOR, "NEC"),
1116 			DMI_MATCH(DMI_PRODUCT_NAME, "PC-LZ750LS"),
1117 		},
1118 	},
1119 	{
1120 		/* Acer Aspire V5-573G */
1121 		.callback = battery_notification_delay_quirk,
1122 		.matches = {
1123 			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
1124 			DMI_MATCH(DMI_PRODUCT_NAME, "Aspire V5-573G"),
1125 		},
1126 	},
1127 	{
1128 		/* Point of View mobii wintab p800w */
1129 		.callback = battery_ac_is_broken_quirk,
1130 		.matches = {
1131 			DMI_MATCH(DMI_BOARD_VENDOR, "AMI Corporation"),
1132 			DMI_MATCH(DMI_BOARD_NAME, "Aptio CRB"),
1133 			DMI_MATCH(DMI_BIOS_VERSION, "3BAIR1013"),
1134 			/* Above matches are too generic, add bios-date match */
1135 			DMI_MATCH(DMI_BIOS_DATE, "08/22/2014"),
1136 		},
1137 	},
1138 	{
1139 		/*
1140 		 * On Lenovo ThinkPads the BIOS specification defines
1141 		 * a state when the bits for charging and discharging
1142 		 * are both set to 0. That state is "Not Charging".
1143 		 */
1144 		.callback = battery_quirk_not_charging,
1145 		.ident = "Lenovo ThinkPad",
1146 		.matches = {
1147 			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
1148 			DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad"),
1149 		},
1150 	},
1151 	{},
1152 };
1153 
1154 /*
1155  * Some machines'(E,G Lenovo Z480) ECs are not stable
1156  * during boot up and this causes battery driver fails to be
1157  * probed due to failure of getting battery information
1158  * from EC sometimes. After several retries, the operation
1159  * may work. So add retry code here and 20ms sleep between
1160  * every retries.
1161  */
1162 static int acpi_battery_update_retry(struct acpi_battery *battery)
1163 {
1164 	int retry, ret;
1165 
1166 	for (retry = 5; retry; retry--) {
1167 		ret = acpi_battery_update(battery, false);
1168 		if (!ret)
1169 			break;
1170 
1171 		msleep(20);
1172 	}
1173 	return ret;
1174 }
1175 
1176 static int acpi_battery_add(struct acpi_device *device)
1177 {
1178 	int result = 0;
1179 	struct acpi_battery *battery = NULL;
1180 
1181 	if (!device)
1182 		return -EINVAL;
1183 
1184 	if (device->dep_unmet)
1185 		return -EPROBE_DEFER;
1186 
1187 	battery = kzalloc(sizeof(struct acpi_battery), GFP_KERNEL);
1188 	if (!battery)
1189 		return -ENOMEM;
1190 	battery->device = device;
1191 	strcpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
1192 	strcpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
1193 	device->driver_data = battery;
1194 	mutex_init(&battery->lock);
1195 	mutex_init(&battery->sysfs_lock);
1196 	if (acpi_has_method(battery->device->handle, "_BIX"))
1197 		set_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags);
1198 
1199 	result = acpi_battery_update_retry(battery);
1200 	if (result)
1201 		goto fail;
1202 
1203 	pr_info("Slot [%s] (battery %s)\n", acpi_device_bid(device),
1204 		device->status.battery_present ? "present" : "absent");
1205 
1206 	battery->pm_nb.notifier_call = battery_notify;
1207 	register_pm_notifier(&battery->pm_nb);
1208 
1209 	device_init_wakeup(&device->dev, 1);
1210 
1211 	return result;
1212 
1213 fail:
1214 	sysfs_remove_battery(battery);
1215 	mutex_destroy(&battery->lock);
1216 	mutex_destroy(&battery->sysfs_lock);
1217 	kfree(battery);
1218 	return result;
1219 }
1220 
1221 static int acpi_battery_remove(struct acpi_device *device)
1222 {
1223 	struct acpi_battery *battery = NULL;
1224 
1225 	if (!device || !acpi_driver_data(device))
1226 		return -EINVAL;
1227 	device_init_wakeup(&device->dev, 0);
1228 	battery = acpi_driver_data(device);
1229 	unregister_pm_notifier(&battery->pm_nb);
1230 	sysfs_remove_battery(battery);
1231 	mutex_destroy(&battery->lock);
1232 	mutex_destroy(&battery->sysfs_lock);
1233 	kfree(battery);
1234 	return 0;
1235 }
1236 
1237 #ifdef CONFIG_PM_SLEEP
1238 /* this is needed to learn about changes made in suspended state */
1239 static int acpi_battery_resume(struct device *dev)
1240 {
1241 	struct acpi_battery *battery;
1242 
1243 	if (!dev)
1244 		return -EINVAL;
1245 
1246 	battery = acpi_driver_data(to_acpi_device(dev));
1247 	if (!battery)
1248 		return -EINVAL;
1249 
1250 	battery->update_time = 0;
1251 	acpi_battery_update(battery, true);
1252 	return 0;
1253 }
1254 #else
1255 #define acpi_battery_resume NULL
1256 #endif
1257 
1258 static SIMPLE_DEV_PM_OPS(acpi_battery_pm, NULL, acpi_battery_resume);
1259 
1260 static struct acpi_driver acpi_battery_driver = {
1261 	.name = "battery",
1262 	.class = ACPI_BATTERY_CLASS,
1263 	.ids = battery_device_ids,
1264 	.flags = ACPI_DRIVER_ALL_NOTIFY_EVENTS,
1265 	.ops = {
1266 		.add = acpi_battery_add,
1267 		.remove = acpi_battery_remove,
1268 		.notify = acpi_battery_notify,
1269 		},
1270 	.drv.pm = &acpi_battery_pm,
1271 };
1272 
1273 static void __init acpi_battery_init_async(void *unused, async_cookie_t cookie)
1274 {
1275 	int result;
1276 
1277 	if (acpi_quirk_skip_acpi_ac_and_battery())
1278 		return;
1279 
1280 	dmi_check_system(bat_dmi_table);
1281 
1282 	result = acpi_bus_register_driver(&acpi_battery_driver);
1283 	battery_driver_registered = (result == 0);
1284 }
1285 
1286 static int __init acpi_battery_init(void)
1287 {
1288 	if (acpi_disabled)
1289 		return -ENODEV;
1290 
1291 	async_cookie = async_schedule(acpi_battery_init_async, NULL);
1292 	return 0;
1293 }
1294 
1295 static void __exit acpi_battery_exit(void)
1296 {
1297 	async_synchronize_cookie(async_cookie + 1);
1298 	if (battery_driver_registered) {
1299 		acpi_bus_unregister_driver(&acpi_battery_driver);
1300 		battery_hook_exit();
1301 	}
1302 }
1303 
1304 module_init(acpi_battery_init);
1305 module_exit(acpi_battery_exit);
1306