xref: /openbmc/linux/drivers/acpi/battery.c (revision 99a15348)
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 
63 	/* Microsoft Surface Go 3 */
64 	{"MSHW0146", 0},
65 
66 	{"", 0},
67 };
68 
69 MODULE_DEVICE_TABLE(acpi, battery_device_ids);
70 
71 enum {
72 	ACPI_BATTERY_ALARM_PRESENT,
73 	ACPI_BATTERY_XINFO_PRESENT,
74 	ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY,
75 	/* On Lenovo Thinkpad models from 2010 and 2011, the power unit
76 	 * switches between mWh and mAh depending on whether the system
77 	 * is running on battery or not.  When mAh is the unit, most
78 	 * reported values are incorrect and need to be adjusted by
79 	 * 10000/design_voltage.  Verified on x201, t410, t410s, and x220.
80 	 * Pre-2010 and 2012 models appear to always report in mWh and
81 	 * are thus unaffected (tested with t42, t61, t500, x200, x300,
82 	 * and x230).  Also, in mid-2012 Lenovo issued a BIOS update for
83 	 *  the 2011 models that fixes the issue (tested on x220 with a
84 	 * post-1.29 BIOS), but as of Nov. 2012, no such update is
85 	 * available for the 2010 models.
86 	 */
87 	ACPI_BATTERY_QUIRK_THINKPAD_MAH,
88 	/* for batteries reporting current capacity with design capacity
89 	 * on a full charge, but showing degradation in full charge cap.
90 	 */
91 	ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE,
92 };
93 
94 struct acpi_battery {
95 	struct mutex lock;
96 	struct mutex sysfs_lock;
97 	struct power_supply *bat;
98 	struct power_supply_desc bat_desc;
99 	struct acpi_device *device;
100 	struct notifier_block pm_nb;
101 	struct list_head list;
102 	unsigned long update_time;
103 	int revision;
104 	int rate_now;
105 	int capacity_now;
106 	int voltage_now;
107 	int design_capacity;
108 	int full_charge_capacity;
109 	int technology;
110 	int design_voltage;
111 	int design_capacity_warning;
112 	int design_capacity_low;
113 	int cycle_count;
114 	int measurement_accuracy;
115 	int max_sampling_time;
116 	int min_sampling_time;
117 	int max_averaging_interval;
118 	int min_averaging_interval;
119 	int capacity_granularity_1;
120 	int capacity_granularity_2;
121 	int alarm;
122 	char model_number[32];
123 	char serial_number[32];
124 	char type[32];
125 	char oem_info[32];
126 	int state;
127 	int power_unit;
128 	unsigned long flags;
129 };
130 
131 #define to_acpi_battery(x) power_supply_get_drvdata(x)
132 
133 static inline int acpi_battery_present(struct acpi_battery *battery)
134 {
135 	return battery->device->status.battery_present;
136 }
137 
138 static int acpi_battery_technology(struct acpi_battery *battery)
139 {
140 	if (!strcasecmp("NiCd", battery->type))
141 		return POWER_SUPPLY_TECHNOLOGY_NiCd;
142 	if (!strcasecmp("NiMH", battery->type))
143 		return POWER_SUPPLY_TECHNOLOGY_NiMH;
144 	if (!strcasecmp("LION", battery->type))
145 		return POWER_SUPPLY_TECHNOLOGY_LION;
146 	if (!strncasecmp("LI-ION", battery->type, 6))
147 		return POWER_SUPPLY_TECHNOLOGY_LION;
148 	if (!strcasecmp("LiP", battery->type))
149 		return POWER_SUPPLY_TECHNOLOGY_LIPO;
150 	return POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
151 }
152 
153 static int acpi_battery_get_state(struct acpi_battery *battery);
154 
155 static int acpi_battery_is_charged(struct acpi_battery *battery)
156 {
157 	/* charging, discharging or critical low */
158 	if (battery->state != 0)
159 		return 0;
160 
161 	/* battery not reporting charge */
162 	if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN ||
163 	    battery->capacity_now == 0)
164 		return 0;
165 
166 	/* good batteries update full_charge as the batteries degrade */
167 	if (battery->full_charge_capacity == battery->capacity_now)
168 		return 1;
169 
170 	/* fallback to using design values for broken batteries */
171 	if (battery->design_capacity <= battery->capacity_now)
172 		return 1;
173 
174 	/* we don't do any sort of metric based on percentages */
175 	return 0;
176 }
177 
178 static bool acpi_battery_is_degraded(struct acpi_battery *battery)
179 {
180 	return ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity) &&
181 		ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity) &&
182 		battery->full_charge_capacity < battery->design_capacity;
183 }
184 
185 static int acpi_battery_handle_discharging(struct acpi_battery *battery)
186 {
187 	/*
188 	 * Some devices wrongly report discharging if the battery's charge level
189 	 * was above the device's start charging threshold atm the AC adapter
190 	 * was plugged in and the device thus did not start a new charge cycle.
191 	 */
192 	if ((battery_ac_is_broken || power_supply_is_system_supplied()) &&
193 	    battery->rate_now == 0)
194 		return POWER_SUPPLY_STATUS_NOT_CHARGING;
195 
196 	return POWER_SUPPLY_STATUS_DISCHARGING;
197 }
198 
199 static int acpi_battery_get_property(struct power_supply *psy,
200 				     enum power_supply_property psp,
201 				     union power_supply_propval *val)
202 {
203 	int full_capacity = ACPI_BATTERY_VALUE_UNKNOWN, ret = 0;
204 	struct acpi_battery *battery = to_acpi_battery(psy);
205 
206 	if (acpi_battery_present(battery)) {
207 		/* run battery update only if it is present */
208 		acpi_battery_get_state(battery);
209 	} else if (psp != POWER_SUPPLY_PROP_PRESENT)
210 		return -ENODEV;
211 	switch (psp) {
212 	case POWER_SUPPLY_PROP_STATUS:
213 		if (battery->state & ACPI_BATTERY_STATE_DISCHARGING)
214 			val->intval = acpi_battery_handle_discharging(battery);
215 		else if (battery->state & ACPI_BATTERY_STATE_CHARGING)
216 			val->intval = POWER_SUPPLY_STATUS_CHARGING;
217 		else if (acpi_battery_is_charged(battery))
218 			val->intval = POWER_SUPPLY_STATUS_FULL;
219 		else if (battery_quirk_notcharging)
220 			val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
221 		else
222 			val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
223 		break;
224 	case POWER_SUPPLY_PROP_PRESENT:
225 		val->intval = acpi_battery_present(battery);
226 		break;
227 	case POWER_SUPPLY_PROP_TECHNOLOGY:
228 		val->intval = acpi_battery_technology(battery);
229 		break;
230 	case POWER_SUPPLY_PROP_CYCLE_COUNT:
231 		val->intval = battery->cycle_count;
232 		break;
233 	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
234 		if (battery->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
235 			ret = -ENODEV;
236 		else
237 			val->intval = battery->design_voltage * 1000;
238 		break;
239 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
240 		if (battery->voltage_now == ACPI_BATTERY_VALUE_UNKNOWN)
241 			ret = -ENODEV;
242 		else
243 			val->intval = battery->voltage_now * 1000;
244 		break;
245 	case POWER_SUPPLY_PROP_CURRENT_NOW:
246 	case POWER_SUPPLY_PROP_POWER_NOW:
247 		if (battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN)
248 			ret = -ENODEV;
249 		else
250 			val->intval = battery->rate_now * 1000;
251 		break;
252 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
253 	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
254 		if (!ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity))
255 			ret = -ENODEV;
256 		else
257 			val->intval = battery->design_capacity * 1000;
258 		break;
259 	case POWER_SUPPLY_PROP_CHARGE_FULL:
260 	case POWER_SUPPLY_PROP_ENERGY_FULL:
261 		if (!ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity))
262 			ret = -ENODEV;
263 		else
264 			val->intval = battery->full_charge_capacity * 1000;
265 		break;
266 	case POWER_SUPPLY_PROP_CHARGE_NOW:
267 	case POWER_SUPPLY_PROP_ENERGY_NOW:
268 		if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN)
269 			ret = -ENODEV;
270 		else
271 			val->intval = battery->capacity_now * 1000;
272 		break;
273 	case POWER_SUPPLY_PROP_CAPACITY:
274 		if (ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity))
275 			full_capacity = battery->full_charge_capacity;
276 		else if (ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity))
277 			full_capacity = battery->design_capacity;
278 
279 		if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN ||
280 		    full_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
281 			ret = -ENODEV;
282 		else
283 			val->intval = battery->capacity_now * 100/
284 					full_capacity;
285 		break;
286 	case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
287 		if (battery->state & ACPI_BATTERY_STATE_CRITICAL)
288 			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
289 		else if (test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags) &&
290 			(battery->capacity_now <= battery->alarm))
291 			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
292 		else if (acpi_battery_is_charged(battery))
293 			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
294 		else
295 			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
296 		break;
297 	case POWER_SUPPLY_PROP_MODEL_NAME:
298 		val->strval = battery->model_number;
299 		break;
300 	case POWER_SUPPLY_PROP_MANUFACTURER:
301 		val->strval = battery->oem_info;
302 		break;
303 	case POWER_SUPPLY_PROP_SERIAL_NUMBER:
304 		val->strval = battery->serial_number;
305 		break;
306 	default:
307 		ret = -EINVAL;
308 	}
309 	return ret;
310 }
311 
312 static enum power_supply_property charge_battery_props[] = {
313 	POWER_SUPPLY_PROP_STATUS,
314 	POWER_SUPPLY_PROP_PRESENT,
315 	POWER_SUPPLY_PROP_TECHNOLOGY,
316 	POWER_SUPPLY_PROP_CYCLE_COUNT,
317 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
318 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
319 	POWER_SUPPLY_PROP_CURRENT_NOW,
320 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
321 	POWER_SUPPLY_PROP_CHARGE_FULL,
322 	POWER_SUPPLY_PROP_CHARGE_NOW,
323 	POWER_SUPPLY_PROP_CAPACITY,
324 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
325 	POWER_SUPPLY_PROP_MODEL_NAME,
326 	POWER_SUPPLY_PROP_MANUFACTURER,
327 	POWER_SUPPLY_PROP_SERIAL_NUMBER,
328 };
329 
330 static enum power_supply_property charge_battery_full_cap_broken_props[] = {
331 	POWER_SUPPLY_PROP_STATUS,
332 	POWER_SUPPLY_PROP_PRESENT,
333 	POWER_SUPPLY_PROP_TECHNOLOGY,
334 	POWER_SUPPLY_PROP_CYCLE_COUNT,
335 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
336 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
337 	POWER_SUPPLY_PROP_CURRENT_NOW,
338 	POWER_SUPPLY_PROP_CHARGE_NOW,
339 	POWER_SUPPLY_PROP_MODEL_NAME,
340 	POWER_SUPPLY_PROP_MANUFACTURER,
341 	POWER_SUPPLY_PROP_SERIAL_NUMBER,
342 };
343 
344 static enum power_supply_property energy_battery_props[] = {
345 	POWER_SUPPLY_PROP_STATUS,
346 	POWER_SUPPLY_PROP_PRESENT,
347 	POWER_SUPPLY_PROP_TECHNOLOGY,
348 	POWER_SUPPLY_PROP_CYCLE_COUNT,
349 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
350 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
351 	POWER_SUPPLY_PROP_POWER_NOW,
352 	POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
353 	POWER_SUPPLY_PROP_ENERGY_FULL,
354 	POWER_SUPPLY_PROP_ENERGY_NOW,
355 	POWER_SUPPLY_PROP_CAPACITY,
356 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
357 	POWER_SUPPLY_PROP_MODEL_NAME,
358 	POWER_SUPPLY_PROP_MANUFACTURER,
359 	POWER_SUPPLY_PROP_SERIAL_NUMBER,
360 };
361 
362 static enum power_supply_property energy_battery_full_cap_broken_props[] = {
363 	POWER_SUPPLY_PROP_STATUS,
364 	POWER_SUPPLY_PROP_PRESENT,
365 	POWER_SUPPLY_PROP_TECHNOLOGY,
366 	POWER_SUPPLY_PROP_CYCLE_COUNT,
367 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
368 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
369 	POWER_SUPPLY_PROP_POWER_NOW,
370 	POWER_SUPPLY_PROP_ENERGY_NOW,
371 	POWER_SUPPLY_PROP_MODEL_NAME,
372 	POWER_SUPPLY_PROP_MANUFACTURER,
373 	POWER_SUPPLY_PROP_SERIAL_NUMBER,
374 };
375 
376 /* Battery Management */
377 struct acpi_offsets {
378 	size_t offset;		/* offset inside struct acpi_sbs_battery */
379 	u8 mode;		/* int or string? */
380 };
381 
382 static const struct acpi_offsets state_offsets[] = {
383 	{offsetof(struct acpi_battery, state), 0},
384 	{offsetof(struct acpi_battery, rate_now), 0},
385 	{offsetof(struct acpi_battery, capacity_now), 0},
386 	{offsetof(struct acpi_battery, voltage_now), 0},
387 };
388 
389 static const struct acpi_offsets info_offsets[] = {
390 	{offsetof(struct acpi_battery, power_unit), 0},
391 	{offsetof(struct acpi_battery, design_capacity), 0},
392 	{offsetof(struct acpi_battery, full_charge_capacity), 0},
393 	{offsetof(struct acpi_battery, technology), 0},
394 	{offsetof(struct acpi_battery, design_voltage), 0},
395 	{offsetof(struct acpi_battery, design_capacity_warning), 0},
396 	{offsetof(struct acpi_battery, design_capacity_low), 0},
397 	{offsetof(struct acpi_battery, capacity_granularity_1), 0},
398 	{offsetof(struct acpi_battery, capacity_granularity_2), 0},
399 	{offsetof(struct acpi_battery, model_number), 1},
400 	{offsetof(struct acpi_battery, serial_number), 1},
401 	{offsetof(struct acpi_battery, type), 1},
402 	{offsetof(struct acpi_battery, oem_info), 1},
403 };
404 
405 static const struct acpi_offsets extended_info_offsets[] = {
406 	{offsetof(struct acpi_battery, revision), 0},
407 	{offsetof(struct acpi_battery, power_unit), 0},
408 	{offsetof(struct acpi_battery, design_capacity), 0},
409 	{offsetof(struct acpi_battery, full_charge_capacity), 0},
410 	{offsetof(struct acpi_battery, technology), 0},
411 	{offsetof(struct acpi_battery, design_voltage), 0},
412 	{offsetof(struct acpi_battery, design_capacity_warning), 0},
413 	{offsetof(struct acpi_battery, design_capacity_low), 0},
414 	{offsetof(struct acpi_battery, cycle_count), 0},
415 	{offsetof(struct acpi_battery, measurement_accuracy), 0},
416 	{offsetof(struct acpi_battery, max_sampling_time), 0},
417 	{offsetof(struct acpi_battery, min_sampling_time), 0},
418 	{offsetof(struct acpi_battery, max_averaging_interval), 0},
419 	{offsetof(struct acpi_battery, min_averaging_interval), 0},
420 	{offsetof(struct acpi_battery, capacity_granularity_1), 0},
421 	{offsetof(struct acpi_battery, capacity_granularity_2), 0},
422 	{offsetof(struct acpi_battery, model_number), 1},
423 	{offsetof(struct acpi_battery, serial_number), 1},
424 	{offsetof(struct acpi_battery, type), 1},
425 	{offsetof(struct acpi_battery, oem_info), 1},
426 };
427 
428 static int extract_package(struct acpi_battery *battery,
429 			   union acpi_object *package,
430 			   const struct acpi_offsets *offsets, int num)
431 {
432 	int i;
433 	union acpi_object *element;
434 
435 	if (package->type != ACPI_TYPE_PACKAGE)
436 		return -EFAULT;
437 	for (i = 0; i < num; ++i) {
438 		if (package->package.count <= i)
439 			return -EFAULT;
440 		element = &package->package.elements[i];
441 		if (offsets[i].mode) {
442 			u8 *ptr = (u8 *)battery + offsets[i].offset;
443 
444 			if (element->type == ACPI_TYPE_STRING ||
445 			    element->type == ACPI_TYPE_BUFFER)
446 				strncpy(ptr, element->string.pointer, 32);
447 			else if (element->type == ACPI_TYPE_INTEGER) {
448 				strncpy(ptr, (u8 *)&element->integer.value,
449 					sizeof(u64));
450 				ptr[sizeof(u64)] = 0;
451 			} else
452 				*ptr = 0; /* don't have value */
453 		} else {
454 			int *x = (int *)((u8 *)battery + offsets[i].offset);
455 			*x = (element->type == ACPI_TYPE_INTEGER) ?
456 				element->integer.value : -1;
457 		}
458 	}
459 	return 0;
460 }
461 
462 static int acpi_battery_get_status(struct acpi_battery *battery)
463 {
464 	if (acpi_bus_get_status(battery->device)) {
465 		acpi_handle_info(battery->device->handle,
466 				 "_STA evaluation failed\n");
467 		return -ENODEV;
468 	}
469 	return 0;
470 }
471 
472 
473 static int extract_battery_info(const int use_bix,
474 			 struct acpi_battery *battery,
475 			 const struct acpi_buffer *buffer)
476 {
477 	int result = -EFAULT;
478 
479 	if (use_bix && battery_bix_broken_package)
480 		result = extract_package(battery, buffer->pointer,
481 				extended_info_offsets + 1,
482 				ARRAY_SIZE(extended_info_offsets) - 1);
483 	else if (use_bix)
484 		result = extract_package(battery, buffer->pointer,
485 				extended_info_offsets,
486 				ARRAY_SIZE(extended_info_offsets));
487 	else
488 		result = extract_package(battery, buffer->pointer,
489 				info_offsets, ARRAY_SIZE(info_offsets));
490 	if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags))
491 		battery->full_charge_capacity = battery->design_capacity;
492 	if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH, &battery->flags) &&
493 	    battery->power_unit && battery->design_voltage) {
494 		battery->design_capacity = battery->design_capacity *
495 		    10000 / battery->design_voltage;
496 		battery->full_charge_capacity = battery->full_charge_capacity *
497 		    10000 / battery->design_voltage;
498 		battery->design_capacity_warning =
499 		    battery->design_capacity_warning *
500 		    10000 / battery->design_voltage;
501 		/* Curiously, design_capacity_low, unlike the rest of them,
502 		 *  is correct.
503 		 */
504 		/* capacity_granularity_* equal 1 on the systems tested, so
505 		 * it's impossible to tell if they would need an adjustment
506 		 * or not if their values were higher.
507 		 */
508 	}
509 	if (test_bit(ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE, &battery->flags) &&
510 	    battery->capacity_now > battery->full_charge_capacity)
511 		battery->capacity_now = battery->full_charge_capacity;
512 
513 	return result;
514 }
515 
516 static int acpi_battery_get_info(struct acpi_battery *battery)
517 {
518 	const int xinfo = test_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags);
519 	int use_bix;
520 	int result = -ENODEV;
521 
522 	if (!acpi_battery_present(battery))
523 		return 0;
524 
525 
526 	for (use_bix = xinfo ? 1 : 0; use_bix >= 0; use_bix--) {
527 		struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
528 		acpi_status status = AE_ERROR;
529 
530 		mutex_lock(&battery->lock);
531 		status = acpi_evaluate_object(battery->device->handle,
532 					      use_bix ? "_BIX":"_BIF",
533 					      NULL, &buffer);
534 		mutex_unlock(&battery->lock);
535 
536 		if (ACPI_FAILURE(status)) {
537 			acpi_handle_info(battery->device->handle,
538 					 "%s evaluation failed: %s\n",
539 					 use_bix ? "_BIX":"_BIF",
540 					 acpi_format_exception(status));
541 		} else {
542 			result = extract_battery_info(use_bix,
543 						      battery,
544 						      &buffer);
545 
546 			kfree(buffer.pointer);
547 			break;
548 		}
549 	}
550 
551 	if (!result && !use_bix && xinfo)
552 		pr_warn(FW_BUG "The _BIX method is broken, using _BIF.\n");
553 
554 	return result;
555 }
556 
557 static int acpi_battery_get_state(struct acpi_battery *battery)
558 {
559 	int result = 0;
560 	acpi_status status = 0;
561 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
562 
563 	if (!acpi_battery_present(battery))
564 		return 0;
565 
566 	if (battery->update_time &&
567 	    time_before(jiffies, battery->update_time +
568 			msecs_to_jiffies(cache_time)))
569 		return 0;
570 
571 	mutex_lock(&battery->lock);
572 	status = acpi_evaluate_object(battery->device->handle, "_BST",
573 				      NULL, &buffer);
574 	mutex_unlock(&battery->lock);
575 
576 	if (ACPI_FAILURE(status)) {
577 		acpi_handle_info(battery->device->handle,
578 				 "_BST evaluation failed: %s",
579 				 acpi_format_exception(status));
580 		return -ENODEV;
581 	}
582 
583 	result = extract_package(battery, buffer.pointer,
584 				 state_offsets, ARRAY_SIZE(state_offsets));
585 	battery->update_time = jiffies;
586 	kfree(buffer.pointer);
587 
588 	/* For buggy DSDTs that report negative 16-bit values for either
589 	 * charging or discharging current and/or report 0 as 65536
590 	 * due to bad math.
591 	 */
592 	if (battery->power_unit == ACPI_BATTERY_POWER_UNIT_MA &&
593 		battery->rate_now != ACPI_BATTERY_VALUE_UNKNOWN &&
594 		(s16)(battery->rate_now) < 0) {
595 		battery->rate_now = abs((s16)battery->rate_now);
596 		pr_warn_once(FW_BUG "(dis)charge rate invalid.\n");
597 	}
598 
599 	if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags)
600 	    && battery->capacity_now >= 0 && battery->capacity_now <= 100)
601 		battery->capacity_now = (battery->capacity_now *
602 				battery->full_charge_capacity) / 100;
603 	if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH, &battery->flags) &&
604 	    battery->power_unit && battery->design_voltage) {
605 		battery->capacity_now = battery->capacity_now *
606 		    10000 / battery->design_voltage;
607 	}
608 	if (test_bit(ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE, &battery->flags) &&
609 	    battery->capacity_now > battery->full_charge_capacity)
610 		battery->capacity_now = battery->full_charge_capacity;
611 
612 	return result;
613 }
614 
615 static int acpi_battery_set_alarm(struct acpi_battery *battery)
616 {
617 	acpi_status status = 0;
618 
619 	if (!acpi_battery_present(battery) ||
620 	    !test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags))
621 		return -ENODEV;
622 
623 	mutex_lock(&battery->lock);
624 	status = acpi_execute_simple_method(battery->device->handle, "_BTP",
625 					    battery->alarm);
626 	mutex_unlock(&battery->lock);
627 
628 	if (ACPI_FAILURE(status))
629 		return -ENODEV;
630 
631 	acpi_handle_debug(battery->device->handle, "Alarm set to %d\n",
632 			  battery->alarm);
633 
634 	return 0;
635 }
636 
637 static int acpi_battery_init_alarm(struct acpi_battery *battery)
638 {
639 	/* See if alarms are supported, and if so, set default */
640 	if (!acpi_has_method(battery->device->handle, "_BTP")) {
641 		clear_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags);
642 		return 0;
643 	}
644 	set_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags);
645 	if (!battery->alarm)
646 		battery->alarm = battery->design_capacity_warning;
647 	return acpi_battery_set_alarm(battery);
648 }
649 
650 static ssize_t acpi_battery_alarm_show(struct device *dev,
651 					struct device_attribute *attr,
652 					char *buf)
653 {
654 	struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
655 
656 	return sprintf(buf, "%d\n", battery->alarm * 1000);
657 }
658 
659 static ssize_t acpi_battery_alarm_store(struct device *dev,
660 					struct device_attribute *attr,
661 					const char *buf, size_t count)
662 {
663 	unsigned long x;
664 	struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
665 
666 	if (sscanf(buf, "%lu\n", &x) == 1)
667 		battery->alarm = x/1000;
668 	if (acpi_battery_present(battery))
669 		acpi_battery_set_alarm(battery);
670 	return count;
671 }
672 
673 static const struct device_attribute alarm_attr = {
674 	.attr = {.name = "alarm", .mode = 0644},
675 	.show = acpi_battery_alarm_show,
676 	.store = acpi_battery_alarm_store,
677 };
678 
679 /*
680  * The Battery Hooking API
681  *
682  * This API is used inside other drivers that need to expose
683  * platform-specific behaviour within the generic driver in a
684  * generic way.
685  *
686  */
687 
688 static LIST_HEAD(acpi_battery_list);
689 static LIST_HEAD(battery_hook_list);
690 static DEFINE_MUTEX(hook_mutex);
691 
692 static void __battery_hook_unregister(struct acpi_battery_hook *hook, int lock)
693 {
694 	struct acpi_battery *battery;
695 	/*
696 	 * In order to remove a hook, we first need to
697 	 * de-register all the batteries that are registered.
698 	 */
699 	if (lock)
700 		mutex_lock(&hook_mutex);
701 	list_for_each_entry(battery, &acpi_battery_list, list) {
702 		hook->remove_battery(battery->bat);
703 	}
704 	list_del(&hook->list);
705 	if (lock)
706 		mutex_unlock(&hook_mutex);
707 	pr_info("extension unregistered: %s\n", hook->name);
708 }
709 
710 void battery_hook_unregister(struct acpi_battery_hook *hook)
711 {
712 	__battery_hook_unregister(hook, 1);
713 }
714 EXPORT_SYMBOL_GPL(battery_hook_unregister);
715 
716 void battery_hook_register(struct acpi_battery_hook *hook)
717 {
718 	struct acpi_battery *battery;
719 
720 	mutex_lock(&hook_mutex);
721 	INIT_LIST_HEAD(&hook->list);
722 	list_add(&hook->list, &battery_hook_list);
723 	/*
724 	 * Now that the driver is registered, we need
725 	 * to notify the hook that a battery is available
726 	 * for each battery, so that the driver may add
727 	 * its attributes.
728 	 */
729 	list_for_each_entry(battery, &acpi_battery_list, list) {
730 		if (hook->add_battery(battery->bat)) {
731 			/*
732 			 * If a add-battery returns non-zero,
733 			 * the registration of the extension has failed,
734 			 * and we will not add it to the list of loaded
735 			 * hooks.
736 			 */
737 			pr_err("extension failed to load: %s", hook->name);
738 			__battery_hook_unregister(hook, 0);
739 			goto end;
740 		}
741 	}
742 	pr_info("new extension: %s\n", hook->name);
743 end:
744 	mutex_unlock(&hook_mutex);
745 }
746 EXPORT_SYMBOL_GPL(battery_hook_register);
747 
748 /*
749  * This function gets called right after the battery sysfs
750  * attributes have been added, so that the drivers that
751  * define custom sysfs attributes can add their own.
752  */
753 static void battery_hook_add_battery(struct acpi_battery *battery)
754 {
755 	struct acpi_battery_hook *hook_node, *tmp;
756 
757 	mutex_lock(&hook_mutex);
758 	INIT_LIST_HEAD(&battery->list);
759 	list_add(&battery->list, &acpi_battery_list);
760 	/*
761 	 * Since we added a new battery to the list, we need to
762 	 * iterate over the hooks and call add_battery for each
763 	 * hook that was registered. This usually happens
764 	 * when a battery gets hotplugged or initialized
765 	 * during the battery module initialization.
766 	 */
767 	list_for_each_entry_safe(hook_node, tmp, &battery_hook_list, list) {
768 		if (hook_node->add_battery(battery->bat)) {
769 			/*
770 			 * The notification of the extensions has failed, to
771 			 * prevent further errors we will unload the extension.
772 			 */
773 			pr_err("error in extension, unloading: %s",
774 					hook_node->name);
775 			__battery_hook_unregister(hook_node, 0);
776 		}
777 	}
778 	mutex_unlock(&hook_mutex);
779 }
780 
781 static void battery_hook_remove_battery(struct acpi_battery *battery)
782 {
783 	struct acpi_battery_hook *hook;
784 
785 	mutex_lock(&hook_mutex);
786 	/*
787 	 * Before removing the hook, we need to remove all
788 	 * custom attributes from the battery.
789 	 */
790 	list_for_each_entry(hook, &battery_hook_list, list) {
791 		hook->remove_battery(battery->bat);
792 	}
793 	/* Then, just remove the battery from the list */
794 	list_del(&battery->list);
795 	mutex_unlock(&hook_mutex);
796 }
797 
798 static void __exit battery_hook_exit(void)
799 {
800 	struct acpi_battery_hook *hook;
801 	struct acpi_battery_hook *ptr;
802 	/*
803 	 * At this point, the acpi_bus_unregister_driver()
804 	 * has called remove for all batteries. We just
805 	 * need to remove the hooks.
806 	 */
807 	list_for_each_entry_safe(hook, ptr, &battery_hook_list, list) {
808 		__battery_hook_unregister(hook, 1);
809 	}
810 	mutex_destroy(&hook_mutex);
811 }
812 
813 static int sysfs_add_battery(struct acpi_battery *battery)
814 {
815 	struct power_supply_config psy_cfg = { .drv_data = battery, };
816 	bool full_cap_broken = false;
817 
818 	if (!ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity) &&
819 	    !ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity))
820 		full_cap_broken = true;
821 
822 	if (battery->power_unit == ACPI_BATTERY_POWER_UNIT_MA) {
823 		if (full_cap_broken) {
824 			battery->bat_desc.properties =
825 			    charge_battery_full_cap_broken_props;
826 			battery->bat_desc.num_properties =
827 			    ARRAY_SIZE(charge_battery_full_cap_broken_props);
828 		} else {
829 			battery->bat_desc.properties = charge_battery_props;
830 			battery->bat_desc.num_properties =
831 			    ARRAY_SIZE(charge_battery_props);
832 		}
833 	} else {
834 		if (full_cap_broken) {
835 			battery->bat_desc.properties =
836 			    energy_battery_full_cap_broken_props;
837 			battery->bat_desc.num_properties =
838 			    ARRAY_SIZE(energy_battery_full_cap_broken_props);
839 		} else {
840 			battery->bat_desc.properties = energy_battery_props;
841 			battery->bat_desc.num_properties =
842 			    ARRAY_SIZE(energy_battery_props);
843 		}
844 	}
845 
846 	battery->bat_desc.name = acpi_device_bid(battery->device);
847 	battery->bat_desc.type = POWER_SUPPLY_TYPE_BATTERY;
848 	battery->bat_desc.get_property = acpi_battery_get_property;
849 
850 	battery->bat = power_supply_register_no_ws(&battery->device->dev,
851 				&battery->bat_desc, &psy_cfg);
852 
853 	if (IS_ERR(battery->bat)) {
854 		int result = PTR_ERR(battery->bat);
855 
856 		battery->bat = NULL;
857 		return result;
858 	}
859 	battery_hook_add_battery(battery);
860 	return device_create_file(&battery->bat->dev, &alarm_attr);
861 }
862 
863 static void sysfs_remove_battery(struct acpi_battery *battery)
864 {
865 	mutex_lock(&battery->sysfs_lock);
866 	if (!battery->bat) {
867 		mutex_unlock(&battery->sysfs_lock);
868 		return;
869 	}
870 	battery_hook_remove_battery(battery);
871 	device_remove_file(&battery->bat->dev, &alarm_attr);
872 	power_supply_unregister(battery->bat);
873 	battery->bat = NULL;
874 	mutex_unlock(&battery->sysfs_lock);
875 }
876 
877 static void find_battery(const struct dmi_header *dm, void *private)
878 {
879 	struct acpi_battery *battery = (struct acpi_battery *)private;
880 	/* Note: the hardcoded offsets below have been extracted from
881 	 * the source code of dmidecode.
882 	 */
883 	if (dm->type == DMI_ENTRY_PORTABLE_BATTERY && dm->length >= 8) {
884 		const u8 *dmi_data = (const u8 *)(dm + 1);
885 		int dmi_capacity = get_unaligned((const u16 *)(dmi_data + 6));
886 
887 		if (dm->length >= 18)
888 			dmi_capacity *= dmi_data[17];
889 		if (battery->design_capacity * battery->design_voltage / 1000
890 		    != dmi_capacity &&
891 		    battery->design_capacity * 10 == dmi_capacity)
892 			set_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH,
893 				&battery->flags);
894 	}
895 }
896 
897 /*
898  * According to the ACPI spec, some kinds of primary batteries can
899  * report percentage battery remaining capacity directly to OS.
900  * In this case, it reports the Last Full Charged Capacity == 100
901  * and BatteryPresentRate == 0xFFFFFFFF.
902  *
903  * Now we found some battery reports percentage remaining capacity
904  * even if it's rechargeable.
905  * https://bugzilla.kernel.org/show_bug.cgi?id=15979
906  *
907  * Handle this correctly so that they won't break userspace.
908  */
909 static void acpi_battery_quirks(struct acpi_battery *battery)
910 {
911 	if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags))
912 		return;
913 
914 	if (battery->full_charge_capacity == 100 &&
915 		battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN &&
916 		battery->capacity_now >= 0 && battery->capacity_now <= 100) {
917 		set_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags);
918 		battery->full_charge_capacity = battery->design_capacity;
919 		battery->capacity_now = (battery->capacity_now *
920 				battery->full_charge_capacity) / 100;
921 	}
922 
923 	if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH, &battery->flags))
924 		return;
925 
926 	if (battery->power_unit && dmi_name_in_vendors("LENOVO")) {
927 		const char *s;
928 
929 		s = dmi_get_system_info(DMI_PRODUCT_VERSION);
930 		if (s && !strncasecmp(s, "ThinkPad", 8)) {
931 			dmi_walk(find_battery, battery);
932 			if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH,
933 				     &battery->flags) &&
934 			    battery->design_voltage) {
935 				battery->design_capacity =
936 				    battery->design_capacity *
937 				    10000 / battery->design_voltage;
938 				battery->full_charge_capacity =
939 				    battery->full_charge_capacity *
940 				    10000 / battery->design_voltage;
941 				battery->design_capacity_warning =
942 				    battery->design_capacity_warning *
943 				    10000 / battery->design_voltage;
944 				battery->capacity_now = battery->capacity_now *
945 				    10000 / battery->design_voltage;
946 			}
947 		}
948 	}
949 
950 	if (test_bit(ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE, &battery->flags))
951 		return;
952 
953 	if (acpi_battery_is_degraded(battery) &&
954 	    battery->capacity_now > battery->full_charge_capacity) {
955 		set_bit(ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE, &battery->flags);
956 		battery->capacity_now = battery->full_charge_capacity;
957 	}
958 }
959 
960 static int acpi_battery_update(struct acpi_battery *battery, bool resume)
961 {
962 	int result = acpi_battery_get_status(battery);
963 
964 	if (result)
965 		return result;
966 
967 	if (!acpi_battery_present(battery)) {
968 		sysfs_remove_battery(battery);
969 		battery->update_time = 0;
970 		return 0;
971 	}
972 
973 	if (resume)
974 		return 0;
975 
976 	if (!battery->update_time) {
977 		result = acpi_battery_get_info(battery);
978 		if (result)
979 			return result;
980 		acpi_battery_init_alarm(battery);
981 	}
982 
983 	result = acpi_battery_get_state(battery);
984 	if (result)
985 		return result;
986 	acpi_battery_quirks(battery);
987 
988 	if (!battery->bat) {
989 		result = sysfs_add_battery(battery);
990 		if (result)
991 			return result;
992 	}
993 
994 	/*
995 	 * Wakeup the system if battery is critical low
996 	 * or lower than the alarm level
997 	 */
998 	if ((battery->state & ACPI_BATTERY_STATE_CRITICAL) ||
999 	    (test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags) &&
1000 	     (battery->capacity_now <= battery->alarm)))
1001 		acpi_pm_wakeup_event(&battery->device->dev);
1002 
1003 	return result;
1004 }
1005 
1006 static void acpi_battery_refresh(struct acpi_battery *battery)
1007 {
1008 	int power_unit;
1009 
1010 	if (!battery->bat)
1011 		return;
1012 
1013 	power_unit = battery->power_unit;
1014 
1015 	acpi_battery_get_info(battery);
1016 
1017 	if (power_unit == battery->power_unit)
1018 		return;
1019 
1020 	/* The battery has changed its reporting units. */
1021 	sysfs_remove_battery(battery);
1022 	sysfs_add_battery(battery);
1023 }
1024 
1025 /* Driver Interface */
1026 static void acpi_battery_notify(struct acpi_device *device, u32 event)
1027 {
1028 	struct acpi_battery *battery = acpi_driver_data(device);
1029 	struct power_supply *old;
1030 
1031 	if (!battery)
1032 		return;
1033 	old = battery->bat;
1034 	/*
1035 	 * On Acer Aspire V5-573G notifications are sometimes triggered too
1036 	 * early. For example, when AC is unplugged and notification is
1037 	 * triggered, battery state is still reported as "Full", and changes to
1038 	 * "Discharging" only after short delay, without any notification.
1039 	 */
1040 	if (battery_notification_delay_ms > 0)
1041 		msleep(battery_notification_delay_ms);
1042 	if (event == ACPI_BATTERY_NOTIFY_INFO)
1043 		acpi_battery_refresh(battery);
1044 	acpi_battery_update(battery, false);
1045 	acpi_bus_generate_netlink_event(device->pnp.device_class,
1046 					dev_name(&device->dev), event,
1047 					acpi_battery_present(battery));
1048 	acpi_notifier_call_chain(device, event, acpi_battery_present(battery));
1049 	/* acpi_battery_update could remove power_supply object */
1050 	if (old && battery->bat)
1051 		power_supply_changed(battery->bat);
1052 }
1053 
1054 static int battery_notify(struct notifier_block *nb,
1055 			       unsigned long mode, void *_unused)
1056 {
1057 	struct acpi_battery *battery = container_of(nb, struct acpi_battery,
1058 						    pm_nb);
1059 	int result;
1060 
1061 	switch (mode) {
1062 	case PM_POST_HIBERNATION:
1063 	case PM_POST_SUSPEND:
1064 		if (!acpi_battery_present(battery))
1065 			return 0;
1066 
1067 		if (battery->bat) {
1068 			acpi_battery_refresh(battery);
1069 		} else {
1070 			result = acpi_battery_get_info(battery);
1071 			if (result)
1072 				return result;
1073 
1074 			result = sysfs_add_battery(battery);
1075 			if (result)
1076 				return result;
1077 		}
1078 
1079 		acpi_battery_init_alarm(battery);
1080 		acpi_battery_get_state(battery);
1081 		break;
1082 	}
1083 
1084 	return 0;
1085 }
1086 
1087 static int __init
1088 battery_bix_broken_package_quirk(const struct dmi_system_id *d)
1089 {
1090 	battery_bix_broken_package = 1;
1091 	return 0;
1092 }
1093 
1094 static int __init
1095 battery_notification_delay_quirk(const struct dmi_system_id *d)
1096 {
1097 	battery_notification_delay_ms = 1000;
1098 	return 0;
1099 }
1100 
1101 static int __init
1102 battery_ac_is_broken_quirk(const struct dmi_system_id *d)
1103 {
1104 	battery_ac_is_broken = 1;
1105 	return 0;
1106 }
1107 
1108 static int __init battery_quirk_not_charging(const struct dmi_system_id *d)
1109 {
1110 	battery_quirk_notcharging = 1;
1111 	return 0;
1112 }
1113 
1114 static const struct dmi_system_id bat_dmi_table[] __initconst = {
1115 	{
1116 		/* NEC LZ750/LS */
1117 		.callback = battery_bix_broken_package_quirk,
1118 		.matches = {
1119 			DMI_MATCH(DMI_SYS_VENDOR, "NEC"),
1120 			DMI_MATCH(DMI_PRODUCT_NAME, "PC-LZ750LS"),
1121 		},
1122 	},
1123 	{
1124 		/* Acer Aspire V5-573G */
1125 		.callback = battery_notification_delay_quirk,
1126 		.matches = {
1127 			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
1128 			DMI_MATCH(DMI_PRODUCT_NAME, "Aspire V5-573G"),
1129 		},
1130 	},
1131 	{
1132 		/* Point of View mobii wintab p800w */
1133 		.callback = battery_ac_is_broken_quirk,
1134 		.matches = {
1135 			DMI_MATCH(DMI_BOARD_VENDOR, "AMI Corporation"),
1136 			DMI_MATCH(DMI_BOARD_NAME, "Aptio CRB"),
1137 			DMI_MATCH(DMI_BIOS_VERSION, "3BAIR1013"),
1138 			/* Above matches are too generic, add bios-date match */
1139 			DMI_MATCH(DMI_BIOS_DATE, "08/22/2014"),
1140 		},
1141 	},
1142 	{
1143 		/*
1144 		 * On Lenovo ThinkPads the BIOS specification defines
1145 		 * a state when the bits for charging and discharging
1146 		 * are both set to 0. That state is "Not Charging".
1147 		 */
1148 		.callback = battery_quirk_not_charging,
1149 		.ident = "Lenovo ThinkPad",
1150 		.matches = {
1151 			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
1152 			DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad"),
1153 		},
1154 	},
1155 	{
1156 		/* Microsoft Surface Go 3 */
1157 		.callback = battery_notification_delay_quirk,
1158 		.matches = {
1159 			DMI_MATCH(DMI_SYS_VENDOR, "Microsoft Corporation"),
1160 			DMI_MATCH(DMI_PRODUCT_NAME, "Surface Go 3"),
1161 		},
1162 	},
1163 	{},
1164 };
1165 
1166 /*
1167  * Some machines'(E,G Lenovo Z480) ECs are not stable
1168  * during boot up and this causes battery driver fails to be
1169  * probed due to failure of getting battery information
1170  * from EC sometimes. After several retries, the operation
1171  * may work. So add retry code here and 20ms sleep between
1172  * every retries.
1173  */
1174 static int acpi_battery_update_retry(struct acpi_battery *battery)
1175 {
1176 	int retry, ret;
1177 
1178 	for (retry = 5; retry; retry--) {
1179 		ret = acpi_battery_update(battery, false);
1180 		if (!ret)
1181 			break;
1182 
1183 		msleep(20);
1184 	}
1185 	return ret;
1186 }
1187 
1188 static int acpi_battery_add(struct acpi_device *device)
1189 {
1190 	int result = 0;
1191 	struct acpi_battery *battery = NULL;
1192 
1193 	if (!device)
1194 		return -EINVAL;
1195 
1196 	if (device->dep_unmet)
1197 		return -EPROBE_DEFER;
1198 
1199 	battery = kzalloc(sizeof(struct acpi_battery), GFP_KERNEL);
1200 	if (!battery)
1201 		return -ENOMEM;
1202 	battery->device = device;
1203 	strcpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
1204 	strcpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
1205 	device->driver_data = battery;
1206 	mutex_init(&battery->lock);
1207 	mutex_init(&battery->sysfs_lock);
1208 	if (acpi_has_method(battery->device->handle, "_BIX"))
1209 		set_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags);
1210 
1211 	result = acpi_battery_update_retry(battery);
1212 	if (result)
1213 		goto fail;
1214 
1215 	pr_info("Slot [%s] (battery %s)\n", acpi_device_bid(device),
1216 		device->status.battery_present ? "present" : "absent");
1217 
1218 	battery->pm_nb.notifier_call = battery_notify;
1219 	register_pm_notifier(&battery->pm_nb);
1220 
1221 	device_init_wakeup(&device->dev, 1);
1222 
1223 	return result;
1224 
1225 fail:
1226 	sysfs_remove_battery(battery);
1227 	mutex_destroy(&battery->lock);
1228 	mutex_destroy(&battery->sysfs_lock);
1229 	kfree(battery);
1230 	return result;
1231 }
1232 
1233 static int acpi_battery_remove(struct acpi_device *device)
1234 {
1235 	struct acpi_battery *battery = NULL;
1236 
1237 	if (!device || !acpi_driver_data(device))
1238 		return -EINVAL;
1239 	device_init_wakeup(&device->dev, 0);
1240 	battery = acpi_driver_data(device);
1241 	unregister_pm_notifier(&battery->pm_nb);
1242 	sysfs_remove_battery(battery);
1243 	mutex_destroy(&battery->lock);
1244 	mutex_destroy(&battery->sysfs_lock);
1245 	kfree(battery);
1246 	return 0;
1247 }
1248 
1249 #ifdef CONFIG_PM_SLEEP
1250 /* this is needed to learn about changes made in suspended state */
1251 static int acpi_battery_resume(struct device *dev)
1252 {
1253 	struct acpi_battery *battery;
1254 
1255 	if (!dev)
1256 		return -EINVAL;
1257 
1258 	battery = acpi_driver_data(to_acpi_device(dev));
1259 	if (!battery)
1260 		return -EINVAL;
1261 
1262 	battery->update_time = 0;
1263 	acpi_battery_update(battery, true);
1264 	return 0;
1265 }
1266 #else
1267 #define acpi_battery_resume NULL
1268 #endif
1269 
1270 static SIMPLE_DEV_PM_OPS(acpi_battery_pm, NULL, acpi_battery_resume);
1271 
1272 static struct acpi_driver acpi_battery_driver = {
1273 	.name = "battery",
1274 	.class = ACPI_BATTERY_CLASS,
1275 	.ids = battery_device_ids,
1276 	.flags = ACPI_DRIVER_ALL_NOTIFY_EVENTS,
1277 	.ops = {
1278 		.add = acpi_battery_add,
1279 		.remove = acpi_battery_remove,
1280 		.notify = acpi_battery_notify,
1281 		},
1282 	.drv.pm = &acpi_battery_pm,
1283 };
1284 
1285 static void __init acpi_battery_init_async(void *unused, async_cookie_t cookie)
1286 {
1287 	int result;
1288 
1289 	if (acpi_quirk_skip_acpi_ac_and_battery())
1290 		return;
1291 
1292 	dmi_check_system(bat_dmi_table);
1293 
1294 	result = acpi_bus_register_driver(&acpi_battery_driver);
1295 	battery_driver_registered = (result == 0);
1296 }
1297 
1298 static int __init acpi_battery_init(void)
1299 {
1300 	if (acpi_disabled)
1301 		return -ENODEV;
1302 
1303 	async_cookie = async_schedule(acpi_battery_init_async, NULL);
1304 	return 0;
1305 }
1306 
1307 static void __exit acpi_battery_exit(void)
1308 {
1309 	async_synchronize_cookie(async_cookie + 1);
1310 	if (battery_driver_registered) {
1311 		acpi_bus_unregister_driver(&acpi_battery_driver);
1312 		battery_hook_exit();
1313 	}
1314 }
1315 
1316 module_init(acpi_battery_init);
1317 module_exit(acpi_battery_exit);
1318