xref: /linux/drivers/acpi/battery.c (revision 3382bfbca58c7d5ee3f31a7b37fbeb208e98e656)
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/ctype.h>
14 #include <linux/delay.h>
15 #include <linux/dmi.h>
16 #include <linux/jiffies.h>
17 #include <linux/kernel.h>
18 #include <linux/kfifo.h>
19 #include <linux/list.h>
20 #include <linux/lockdep.h>
21 #include <linux/module.h>
22 #include <linux/mutex.h>
23 #include <linux/platform_device.h>
24 #include <linux/slab.h>
25 #include <linux/suspend.h>
26 #include <linux/types.h>
27 #include <linux/workqueue.h>
28 
29 #include <linux/unaligned.h>
30 
31 #include <linux/acpi.h>
32 #include <linux/power_supply.h>
33 
34 #include <acpi/battery.h>
35 
36 #define ACPI_BATTERY_VALUE_UNKNOWN 0xFFFFFFFF
37 #define ACPI_BATTERY_CAPACITY_VALID(capacity) \
38 	((capacity) != 0 && (capacity) != ACPI_BATTERY_VALUE_UNKNOWN)
39 
40 /* Battery power unit: 0 means mW, 1 means mA */
41 #define ACPI_BATTERY_POWER_UNIT_MA	1
42 
43 #define ACPI_BATTERY_STATE_DISCHARGING		0x1
44 #define ACPI_BATTERY_STATE_CHARGING		0x2
45 #define ACPI_BATTERY_STATE_CRITICAL		0x4
46 #define ACPI_BATTERY_STATE_CHARGE_LIMITING	0x8
47 
48 #define MAX_STRING_LENGTH	64
49 
50 #define MAX_QUEUED_EVENTS	16
51 #define NOTIF_MERGING_MS	10
52 
53 MODULE_AUTHOR("Paul Diefenbaugh");
54 MODULE_AUTHOR("Alexey Starikovskiy <astarikovskiy@suse.de>");
55 MODULE_DESCRIPTION("ACPI Battery Driver");
56 MODULE_LICENSE("GPL");
57 
58 static int battery_bix_broken_package;
59 static int battery_notification_delay_ms;
60 static int battery_ac_is_broken;
61 static unsigned int cache_time = 1000;
62 module_param(cache_time, uint, 0644);
63 MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
64 
65 static const struct acpi_device_id battery_device_ids[] = {
66 	{"PNP0C0A", 0},
67 
68 	/* Microsoft Surface Go 3 */
69 	{"MSHW0146", 0},
70 
71 	{"", 0},
72 };
73 
74 MODULE_DEVICE_TABLE(acpi, battery_device_ids);
75 
76 enum {
77 	ACPI_BATTERY_ALARM_PRESENT,
78 	ACPI_BATTERY_XINFO_PRESENT,
79 	ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY,
80 	/* On Lenovo Thinkpad models from 2010 and 2011, the power unit
81 	 * switches between mWh and mAh depending on whether the system
82 	 * is running on battery or not.  When mAh is the unit, most
83 	 * reported values are incorrect and need to be adjusted by
84 	 * 10000/design_voltage.  Verified on x201, t410, t410s, and x220.
85 	 * Pre-2010 and 2012 models appear to always report in mWh and
86 	 * are thus unaffected (tested with t42, t61, t500, x200, x300,
87 	 * and x230).  Also, in mid-2012 Lenovo issued a BIOS update for
88 	 *  the 2011 models that fixes the issue (tested on x220 with a
89 	 * post-1.29 BIOS), but as of Nov. 2012, no such update is
90 	 * available for the 2010 models.
91 	 */
92 	ACPI_BATTERY_QUIRK_THINKPAD_MAH,
93 	/* for batteries reporting current capacity with design capacity
94 	 * on a full charge, but showing degradation in full charge cap.
95 	 */
96 	ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE,
97 };
98 
99 struct acpi_battery {
100 	struct mutex update_lock;
101 	struct power_supply *bat;
102 	struct power_supply_desc bat_desc;
103 	struct acpi_device *device;
104 	struct device *phys_dev;
105 	struct kfifo acpi_notif_fifo;
106 	struct delayed_work acpi_notif_dwork;
107 	struct notifier_block pm_nb;
108 	struct list_head list;
109 	unsigned long flags;
110 
111 	struct mutex property_lock; /* Protects properties below. */
112 	unsigned long update_time;
113 	int revision;
114 	int rate_now;
115 	int capacity_now;
116 	int voltage_now;
117 	int design_capacity;
118 	int full_charge_capacity;
119 	int technology;
120 	int design_voltage;
121 	int design_capacity_warning;
122 	int design_capacity_low;
123 	int cycle_count;
124 	int measurement_accuracy;
125 	int max_sampling_time;
126 	int min_sampling_time;
127 	int max_averaging_interval;
128 	int min_averaging_interval;
129 	int capacity_granularity_1;
130 	int capacity_granularity_2;
131 	int alarm;
132 	char model_number[MAX_STRING_LENGTH];
133 	char serial_number[MAX_STRING_LENGTH];
134 	char type[MAX_STRING_LENGTH];
135 	char oem_info[MAX_STRING_LENGTH];
136 	int state;
137 	int power_unit;
138 };
139 
140 #define to_acpi_battery(x) power_supply_get_drvdata(x)
141 
acpi_battery_present(struct acpi_battery * battery)142 static inline int acpi_battery_present(struct acpi_battery *battery)
143 {
144 	return battery->device->status.battery_present;
145 }
146 
acpi_battery_technology(struct acpi_battery * battery)147 static int acpi_battery_technology(struct acpi_battery *battery)
148 {
149 	if (!strcasecmp("NiCd", battery->type))
150 		return POWER_SUPPLY_TECHNOLOGY_NiCd;
151 	if (!strcasecmp("NiMH", battery->type))
152 		return POWER_SUPPLY_TECHNOLOGY_NiMH;
153 	if (!strcasecmp("LION", battery->type))
154 		return POWER_SUPPLY_TECHNOLOGY_LION;
155 	if (!strncasecmp("LI-ION", battery->type, 6))
156 		return POWER_SUPPLY_TECHNOLOGY_LION;
157 	if (!strcasecmp("LiP", battery->type))
158 		return POWER_SUPPLY_TECHNOLOGY_LIPO;
159 	return POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
160 }
161 
162 static int acpi_battery_get_state(struct acpi_battery *battery);
163 
acpi_battery_is_full(struct acpi_battery * battery)164 static bool acpi_battery_is_full(struct acpi_battery *battery)
165 {
166 	/* battery not reporting charge */
167 	if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN ||
168 	    battery->capacity_now == 0)
169 		return false;
170 
171 	/* good batteries update full_charge as the batteries degrade */
172 	if (battery->full_charge_capacity == battery->capacity_now)
173 		return true;
174 
175 	/* fallback to using design values for broken batteries */
176 	return battery->design_capacity <= battery->capacity_now;
177 }
178 
acpi_battery_is_charged(struct acpi_battery * battery)179 static int acpi_battery_is_charged(struct acpi_battery *battery)
180 {
181 	/* charging, discharging, critical low or charge limited */
182 	if (battery->state != 0)
183 		return 0;
184 
185 	return acpi_battery_is_full(battery);
186 }
187 
acpi_battery_is_degraded(struct acpi_battery * battery)188 static bool acpi_battery_is_degraded(struct acpi_battery *battery)
189 {
190 	return ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity) &&
191 		ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity) &&
192 		battery->full_charge_capacity < battery->design_capacity;
193 }
194 
acpi_battery_get_property(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)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 	/* run battery update only if it is present */
203 	if (!acpi_battery_present(battery)) {
204 		switch (psp) {
205 		case POWER_SUPPLY_PROP_PRESENT:
206 			val->intval = 0;
207 			return 0;
208 		default:
209 			return -ENODEV;
210 		}
211 	}
212 
213 	mutex_lock(&battery->property_lock);
214 
215 	acpi_battery_get_state(battery);
216 
217 	switch (psp) {
218 	case POWER_SUPPLY_PROP_STATUS:
219 		/*
220 		 * Some devices wrongly report discharging if the battery's charge level
221 		 * was above the device's start charging threshold atm the AC adapter
222 		 * was plugged in and the device thus did not start a new charge cycle.
223 		 */
224 		if (battery->state & ACPI_BATTERY_STATE_DISCHARGING)
225 			if (battery->rate_now != 0) {
226 				val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
227 			} else if (battery_ac_is_broken) {
228 				val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
229 			} else {
230 				mutex_unlock(&battery->property_lock);
231 
232 				val->intval = power_supply_is_system_supplied()
233 					? POWER_SUPPLY_STATUS_NOT_CHARGING
234 					: POWER_SUPPLY_STATUS_DISCHARGING;
235 				return 0;
236 			}
237 		else if (battery->state & ACPI_BATTERY_STATE_CHARGING)
238 			/* Check the rate and capacity to validate the status. */
239 			if (!acpi_battery_is_full(battery) ||
240 			    (battery->rate_now != ACPI_BATTERY_VALUE_UNKNOWN &&
241 			     battery->rate_now > 0)) {
242 				val->intval = POWER_SUPPLY_STATUS_CHARGING;
243 			} else {
244 				/* Full and zero rate. */
245 				val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
246 			}
247 		else if (battery->state & ACPI_BATTERY_STATE_CHARGE_LIMITING)
248 			val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
249 		else if (acpi_battery_is_charged(battery))
250 			val->intval = POWER_SUPPLY_STATUS_FULL;
251 		else
252 			val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
253 		break;
254 	case POWER_SUPPLY_PROP_PRESENT:
255 		val->intval = acpi_battery_present(battery);
256 		break;
257 	case POWER_SUPPLY_PROP_TECHNOLOGY:
258 		val->intval = acpi_battery_technology(battery);
259 		break;
260 	case POWER_SUPPLY_PROP_CYCLE_COUNT:
261 		val->intval = battery->cycle_count;
262 		break;
263 	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
264 		if (battery->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
265 			ret = -ENODEV;
266 		else
267 			val->intval = battery->design_voltage * 1000;
268 		break;
269 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
270 		if (battery->voltage_now == ACPI_BATTERY_VALUE_UNKNOWN)
271 			ret = -ENODEV;
272 		else
273 			val->intval = battery->voltage_now * 1000;
274 		break;
275 	case POWER_SUPPLY_PROP_CURRENT_NOW:
276 	case POWER_SUPPLY_PROP_POWER_NOW:
277 		if (battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN)
278 			ret = -ENODEV;
279 		else
280 			val->intval = battery->rate_now * 1000;
281 		break;
282 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
283 	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
284 		if (!ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity))
285 			ret = -ENODEV;
286 		else
287 			val->intval = battery->design_capacity * 1000;
288 		break;
289 	case POWER_SUPPLY_PROP_CHARGE_FULL:
290 	case POWER_SUPPLY_PROP_ENERGY_FULL:
291 		if (!ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity))
292 			ret = -ENODEV;
293 		else
294 			val->intval = battery->full_charge_capacity * 1000;
295 		break;
296 	case POWER_SUPPLY_PROP_CHARGE_NOW:
297 	case POWER_SUPPLY_PROP_ENERGY_NOW:
298 		if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN)
299 			ret = -ENODEV;
300 		else
301 			val->intval = battery->capacity_now * 1000;
302 		break;
303 	case POWER_SUPPLY_PROP_CAPACITY:
304 		if (ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity))
305 			full_capacity = battery->full_charge_capacity;
306 		else if (ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity))
307 			full_capacity = battery->design_capacity;
308 
309 		if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN ||
310 		    full_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
311 			ret = -ENODEV;
312 		else
313 			val->intval = DIV_ROUND_CLOSEST_ULL(battery->capacity_now * 100ULL,
314 					full_capacity);
315 		break;
316 	case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
317 		if (battery->state & ACPI_BATTERY_STATE_CRITICAL)
318 			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
319 		else if (test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags) &&
320 			(battery->capacity_now <= battery->alarm))
321 			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
322 		else if (acpi_battery_is_charged(battery))
323 			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
324 		else
325 			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
326 		break;
327 	case POWER_SUPPLY_PROP_MODEL_NAME:
328 		val->strval = battery->model_number;
329 		break;
330 	case POWER_SUPPLY_PROP_MANUFACTURER:
331 		val->strval = battery->oem_info;
332 		break;
333 	case POWER_SUPPLY_PROP_SERIAL_NUMBER:
334 		val->strval = battery->serial_number;
335 		break;
336 	default:
337 		ret = -EINVAL;
338 	}
339 
340 	mutex_unlock(&battery->property_lock);
341 	return ret;
342 }
343 
344 static const enum power_supply_property charge_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_CURRENT_NOW,
352 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
353 	POWER_SUPPLY_PROP_CHARGE_FULL,
354 	POWER_SUPPLY_PROP_CHARGE_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 const enum power_supply_property charge_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_CURRENT_NOW,
370 	POWER_SUPPLY_PROP_CHARGE_NOW,
371 	POWER_SUPPLY_PROP_MODEL_NAME,
372 	POWER_SUPPLY_PROP_MANUFACTURER,
373 	POWER_SUPPLY_PROP_SERIAL_NUMBER,
374 };
375 
376 static const enum power_supply_property energy_battery_props[] = {
377 	POWER_SUPPLY_PROP_STATUS,
378 	POWER_SUPPLY_PROP_PRESENT,
379 	POWER_SUPPLY_PROP_TECHNOLOGY,
380 	POWER_SUPPLY_PROP_CYCLE_COUNT,
381 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
382 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
383 	POWER_SUPPLY_PROP_POWER_NOW,
384 	POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
385 	POWER_SUPPLY_PROP_ENERGY_FULL,
386 	POWER_SUPPLY_PROP_ENERGY_NOW,
387 	POWER_SUPPLY_PROP_CAPACITY,
388 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
389 	POWER_SUPPLY_PROP_MODEL_NAME,
390 	POWER_SUPPLY_PROP_MANUFACTURER,
391 	POWER_SUPPLY_PROP_SERIAL_NUMBER,
392 };
393 
394 static const enum power_supply_property energy_battery_full_cap_broken_props[] = {
395 	POWER_SUPPLY_PROP_STATUS,
396 	POWER_SUPPLY_PROP_PRESENT,
397 	POWER_SUPPLY_PROP_TECHNOLOGY,
398 	POWER_SUPPLY_PROP_CYCLE_COUNT,
399 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
400 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
401 	POWER_SUPPLY_PROP_POWER_NOW,
402 	POWER_SUPPLY_PROP_ENERGY_NOW,
403 	POWER_SUPPLY_PROP_MODEL_NAME,
404 	POWER_SUPPLY_PROP_MANUFACTURER,
405 	POWER_SUPPLY_PROP_SERIAL_NUMBER,
406 };
407 
408 /* Battery Management */
409 struct acpi_offsets {
410 	size_t offset;		/* offset inside struct acpi_sbs_battery */
411 	u8 mode;		/* int or string? */
412 };
413 
414 static const struct acpi_offsets state_offsets[] = {
415 	{offsetof(struct acpi_battery, state), 0},
416 	{offsetof(struct acpi_battery, rate_now), 0},
417 	{offsetof(struct acpi_battery, capacity_now), 0},
418 	{offsetof(struct acpi_battery, voltage_now), 0},
419 };
420 
421 static const struct acpi_offsets info_offsets[] = {
422 	{offsetof(struct acpi_battery, power_unit), 0},
423 	{offsetof(struct acpi_battery, design_capacity), 0},
424 	{offsetof(struct acpi_battery, full_charge_capacity), 0},
425 	{offsetof(struct acpi_battery, technology), 0},
426 	{offsetof(struct acpi_battery, design_voltage), 0},
427 	{offsetof(struct acpi_battery, design_capacity_warning), 0},
428 	{offsetof(struct acpi_battery, design_capacity_low), 0},
429 	{offsetof(struct acpi_battery, capacity_granularity_1), 0},
430 	{offsetof(struct acpi_battery, capacity_granularity_2), 0},
431 	{offsetof(struct acpi_battery, model_number), 1},
432 	{offsetof(struct acpi_battery, serial_number), 1},
433 	{offsetof(struct acpi_battery, type), 1},
434 	{offsetof(struct acpi_battery, oem_info), 1},
435 };
436 
437 static const struct acpi_offsets extended_info_offsets[] = {
438 	{offsetof(struct acpi_battery, revision), 0},
439 	{offsetof(struct acpi_battery, power_unit), 0},
440 	{offsetof(struct acpi_battery, design_capacity), 0},
441 	{offsetof(struct acpi_battery, full_charge_capacity), 0},
442 	{offsetof(struct acpi_battery, technology), 0},
443 	{offsetof(struct acpi_battery, design_voltage), 0},
444 	{offsetof(struct acpi_battery, design_capacity_warning), 0},
445 	{offsetof(struct acpi_battery, design_capacity_low), 0},
446 	{offsetof(struct acpi_battery, cycle_count), 0},
447 	{offsetof(struct acpi_battery, measurement_accuracy), 0},
448 	{offsetof(struct acpi_battery, max_sampling_time), 0},
449 	{offsetof(struct acpi_battery, min_sampling_time), 0},
450 	{offsetof(struct acpi_battery, max_averaging_interval), 0},
451 	{offsetof(struct acpi_battery, min_averaging_interval), 0},
452 	{offsetof(struct acpi_battery, capacity_granularity_1), 0},
453 	{offsetof(struct acpi_battery, capacity_granularity_2), 0},
454 	{offsetof(struct acpi_battery, model_number), 1},
455 	{offsetof(struct acpi_battery, serial_number), 1},
456 	{offsetof(struct acpi_battery, type), 1},
457 	{offsetof(struct acpi_battery, oem_info), 1},
458 };
459 
extract_package(struct acpi_battery * battery,union acpi_object * package,const struct acpi_offsets * offsets,int num)460 static int extract_package(struct acpi_battery *battery,
461 			   union acpi_object *package,
462 			   const struct acpi_offsets *offsets, int num)
463 {
464 	int i;
465 	union acpi_object *element;
466 
467 	if (package->type != ACPI_TYPE_PACKAGE)
468 		return -EFAULT;
469 	for (i = 0; i < num; ++i) {
470 		if (package->package.count <= i)
471 			return -EFAULT;
472 		element = &package->package.elements[i];
473 		if (offsets[i].mode) {
474 			u8 *ptr = (u8 *)battery + offsets[i].offset;
475 			u32 len = MAX_STRING_LENGTH;
476 
477 			switch (element->type) {
478 			case ACPI_TYPE_BUFFER:
479 				if (len > element->buffer.length + 1)
480 					len = element->buffer.length + 1;
481 
482 				fallthrough;
483 			case ACPI_TYPE_STRING:
484 				strscpy(ptr, element->string.pointer, len);
485 
486 				break;
487 			case ACPI_TYPE_INTEGER:
488 				strscpy(ptr, (u8 *)&element->integer.value, sizeof(u64) + 1);
489 
490 				break;
491 			default:
492 				*ptr = 0; /* don't have value */
493 			}
494 		} else {
495 			int *x = (int *)((u8 *)battery + offsets[i].offset);
496 			*x = (element->type == ACPI_TYPE_INTEGER) ?
497 				element->integer.value : -1;
498 		}
499 	}
500 	return 0;
501 }
502 
acpi_battery_get_status(struct acpi_battery * battery)503 static int acpi_battery_get_status(struct acpi_battery *battery)
504 {
505 	if (acpi_bus_get_status(battery->device)) {
506 		acpi_handle_info(battery->device->handle,
507 				 "_STA evaluation failed\n");
508 		return -ENODEV;
509 	}
510 	return 0;
511 }
512 
acpi_battery_clean_unprintable_chars(char * str,size_t length)513 static void acpi_battery_clean_unprintable_chars(char *str, size_t length)
514 {
515 	for (unsigned int i = 0; i < length; i++) {
516 		if (!isascii(str[i]) || !isprint(str[i])) {
517 			str[i] = '\0';
518 			break;
519 		}
520 	}
521 }
522 
extract_battery_info(const int use_bix,struct acpi_battery * battery,const struct acpi_buffer * buffer)523 static int extract_battery_info(const int use_bix,
524 			 struct acpi_battery *battery,
525 			 const struct acpi_buffer *buffer)
526 {
527 	int result = -EFAULT;
528 
529 	if (use_bix && battery_bix_broken_package)
530 		result = extract_package(battery, buffer->pointer,
531 				extended_info_offsets + 1,
532 				ARRAY_SIZE(extended_info_offsets) - 1);
533 	else if (use_bix)
534 		result = extract_package(battery, buffer->pointer,
535 				extended_info_offsets,
536 				ARRAY_SIZE(extended_info_offsets));
537 	else
538 		result = extract_package(battery, buffer->pointer,
539 				info_offsets, ARRAY_SIZE(info_offsets));
540 	if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags))
541 		battery->full_charge_capacity = battery->design_capacity;
542 	if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH, &battery->flags) &&
543 	    battery->power_unit && battery->design_voltage) {
544 		battery->design_capacity = battery->design_capacity *
545 		    10000 / battery->design_voltage;
546 		battery->full_charge_capacity = battery->full_charge_capacity *
547 		    10000 / battery->design_voltage;
548 		battery->design_capacity_warning =
549 		    battery->design_capacity_warning *
550 		    10000 / battery->design_voltage;
551 		/* Curiously, design_capacity_low, unlike the rest of them,
552 		 *  is correct.
553 		 */
554 		/* capacity_granularity_* equal 1 on the systems tested, so
555 		 * it's impossible to tell if they would need an adjustment
556 		 * or not if their values were higher.
557 		 */
558 	}
559 	if (test_bit(ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE, &battery->flags) &&
560 	    battery->capacity_now > battery->full_charge_capacity)
561 		battery->capacity_now = battery->full_charge_capacity;
562 
563 	if (!result)
564 		acpi_battery_clean_unprintable_chars(battery->model_number,
565 					ARRAY_SIZE(battery->model_number));
566 
567 	return result;
568 }
569 
acpi_battery_get_info(struct acpi_battery * battery)570 static int acpi_battery_get_info(struct acpi_battery *battery)
571 {
572 	const int xinfo = test_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags);
573 	int use_bix;
574 	int result = -ENODEV;
575 
576 	lockdep_assert_held(&battery->property_lock);
577 
578 	if (!acpi_battery_present(battery))
579 		return 0;
580 
581 
582 	for (use_bix = xinfo ? 1 : 0; use_bix >= 0; use_bix--) {
583 		struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
584 		acpi_status status = AE_ERROR;
585 
586 		status = acpi_evaluate_object(battery->device->handle,
587 					      use_bix ? "_BIX":"_BIF",
588 					      NULL, &buffer);
589 
590 		if (ACPI_FAILURE(status)) {
591 			acpi_handle_info(battery->device->handle,
592 					 "%s evaluation failed: %s\n",
593 					 use_bix ? "_BIX":"_BIF",
594 					 acpi_format_exception(status));
595 		} else {
596 			result = extract_battery_info(use_bix,
597 						      battery,
598 						      &buffer);
599 
600 			kfree(buffer.pointer);
601 			break;
602 		}
603 	}
604 
605 	if (!result && !use_bix && xinfo)
606 		pr_warn(FW_BUG "The _BIX method is broken, using _BIF.\n");
607 
608 	return result;
609 }
610 
acpi_battery_get_state(struct acpi_battery * battery)611 static int acpi_battery_get_state(struct acpi_battery *battery)
612 {
613 	int result = 0;
614 	acpi_status status = 0;
615 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
616 
617 	lockdep_assert_held(&battery->property_lock);
618 
619 	if (!acpi_battery_present(battery))
620 		return 0;
621 
622 	if (battery->update_time &&
623 	    time_before(jiffies, battery->update_time +
624 			msecs_to_jiffies(cache_time)))
625 		return 0;
626 
627 	status = acpi_evaluate_object(battery->device->handle, "_BST",
628 				      NULL, &buffer);
629 	if (ACPI_FAILURE(status)) {
630 		acpi_handle_info(battery->device->handle,
631 				 "_BST evaluation failed: %s",
632 				 acpi_format_exception(status));
633 		return -ENODEV;
634 	}
635 
636 	result = extract_package(battery, buffer.pointer,
637 				 state_offsets, ARRAY_SIZE(state_offsets));
638 	battery->update_time = jiffies;
639 	kfree(buffer.pointer);
640 
641 	/* For buggy DSDTs that report negative 16-bit values for either
642 	 * charging or discharging current and/or report 0 as 65536
643 	 * due to bad math.
644 	 */
645 	if (battery->power_unit == ACPI_BATTERY_POWER_UNIT_MA &&
646 		battery->rate_now != ACPI_BATTERY_VALUE_UNKNOWN &&
647 		(s16)(battery->rate_now) < 0) {
648 		battery->rate_now = abs((s16)battery->rate_now);
649 		pr_warn_once(FW_BUG "(dis)charge rate invalid.\n");
650 	}
651 
652 	if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags)
653 	    && battery->capacity_now >= 0 && battery->capacity_now <= 100)
654 		battery->capacity_now = (battery->capacity_now *
655 				battery->full_charge_capacity) / 100;
656 	if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH, &battery->flags) &&
657 	    battery->power_unit && battery->design_voltage) {
658 		battery->capacity_now = battery->capacity_now *
659 		    10000 / battery->design_voltage;
660 	}
661 	if (test_bit(ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE, &battery->flags) &&
662 	    battery->capacity_now > battery->full_charge_capacity)
663 		battery->capacity_now = battery->full_charge_capacity;
664 
665 	return result;
666 }
667 
acpi_battery_set_alarm(struct acpi_battery * battery)668 static int acpi_battery_set_alarm(struct acpi_battery *battery)
669 {
670 	acpi_status status = 0;
671 
672 	lockdep_assert_held(&battery->property_lock);
673 
674 	if (!acpi_battery_present(battery) ||
675 	    !test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags))
676 		return -ENODEV;
677 
678 	status = acpi_execute_simple_method(battery->device->handle, "_BTP",
679 					    battery->alarm);
680 	if (ACPI_FAILURE(status))
681 		return -ENODEV;
682 
683 	acpi_handle_debug(battery->device->handle, "Alarm set to %d\n",
684 			  battery->alarm);
685 
686 	return 0;
687 }
688 
acpi_battery_init_alarm(struct acpi_battery * battery)689 static int acpi_battery_init_alarm(struct acpi_battery *battery)
690 {
691 	lockdep_assert_held(&battery->property_lock);
692 
693 	/* See if alarms are supported, and if so, set default */
694 	if (!acpi_has_method(battery->device->handle, "_BTP")) {
695 		clear_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags);
696 		return 0;
697 	}
698 	set_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags);
699 	if (!battery->alarm)
700 		battery->alarm = battery->design_capacity_warning;
701 	return acpi_battery_set_alarm(battery);
702 }
703 
acpi_battery_alarm_show(struct device * dev,struct device_attribute * attr,char * buf)704 static ssize_t acpi_battery_alarm_show(struct device *dev,
705 					struct device_attribute *attr,
706 					char *buf)
707 {
708 	struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
709 
710 	guard(mutex)(&battery->property_lock);
711 
712 	return sysfs_emit(buf, "%d\n", battery->alarm * 1000);
713 }
714 
acpi_battery_alarm_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)715 static ssize_t acpi_battery_alarm_store(struct device *dev,
716 					struct device_attribute *attr,
717 					const char *buf, size_t count)
718 {
719 	unsigned long x;
720 	struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
721 	int err;
722 
723 	err = kstrtoul(buf, 10, &x);
724 	if (err)
725 		return err;
726 
727 	guard(mutex)(&battery->property_lock);
728 
729 	battery->alarm = x / 1000;
730 	if (acpi_battery_present(battery))
731 		acpi_battery_set_alarm(battery);
732 	return count;
733 }
734 
735 static struct device_attribute alarm_attr = {
736 	.attr = {.name = "alarm", .mode = 0644},
737 	.show = acpi_battery_alarm_show,
738 	.store = acpi_battery_alarm_store,
739 };
740 
741 static struct attribute *acpi_battery_attrs[] = {
742 	&alarm_attr.attr,
743 	NULL
744 };
745 ATTRIBUTE_GROUPS(acpi_battery);
746 
747 /*
748  * The Battery Hooking API
749  *
750  * This API is used inside other drivers that need to expose
751  * platform-specific behaviour within the generic driver in a
752  * generic way.
753  *
754  */
755 
756 static LIST_HEAD(acpi_battery_list);
757 static LIST_HEAD(battery_hook_list);
758 static DEFINE_MUTEX(hook_mutex);
759 
battery_hook_unregister_unlocked(struct acpi_battery_hook * hook)760 static void battery_hook_unregister_unlocked(struct acpi_battery_hook *hook)
761 {
762 	struct acpi_battery *battery;
763 
764 	/*
765 	 * In order to remove a hook, we first need to
766 	 * de-register all the batteries that are registered.
767 	 */
768 	list_for_each_entry(battery, &acpi_battery_list, list) {
769 		if (!hook->remove_battery(battery->bat, hook))
770 			power_supply_changed(battery->bat);
771 	}
772 	list_del_init(&hook->list);
773 
774 	pr_info("hook unregistered: %s\n", hook->name);
775 }
776 
battery_hook_unregister(struct acpi_battery_hook * hook)777 void battery_hook_unregister(struct acpi_battery_hook *hook)
778 {
779 	mutex_lock(&hook_mutex);
780 	/*
781 	 * Ignore already unregistered battery hooks. This might happen
782 	 * if a battery hook was previously unloaded due to an error when
783 	 * adding a new battery.
784 	 */
785 	if (!list_empty(&hook->list))
786 		battery_hook_unregister_unlocked(hook);
787 
788 	mutex_unlock(&hook_mutex);
789 }
790 EXPORT_SYMBOL_GPL(battery_hook_unregister);
791 
battery_hook_register(struct acpi_battery_hook * hook)792 void battery_hook_register(struct acpi_battery_hook *hook)
793 {
794 	struct acpi_battery *battery;
795 
796 	mutex_lock(&hook_mutex);
797 	list_add(&hook->list, &battery_hook_list);
798 	/*
799 	 * Now that the driver is registered, we need
800 	 * to notify the hook that a battery is available
801 	 * for each battery, so that the driver may add
802 	 * its attributes.
803 	 */
804 	list_for_each_entry(battery, &acpi_battery_list, list) {
805 		if (hook->add_battery(battery->bat, hook)) {
806 			/*
807 			 * If a add-battery returns non-zero,
808 			 * the registration of the hook has failed,
809 			 * and we will not add it to the list of loaded
810 			 * hooks.
811 			 */
812 			pr_err("hook failed to load: %s", hook->name);
813 			battery_hook_unregister_unlocked(hook);
814 			goto end;
815 		}
816 
817 		power_supply_changed(battery->bat);
818 	}
819 	pr_info("new hook: %s\n", hook->name);
820 end:
821 	mutex_unlock(&hook_mutex);
822 }
823 EXPORT_SYMBOL_GPL(battery_hook_register);
824 
devm_battery_hook_unregister(void * data)825 static void devm_battery_hook_unregister(void *data)
826 {
827 	struct acpi_battery_hook *hook = data;
828 
829 	battery_hook_unregister(hook);
830 }
831 
devm_battery_hook_register(struct device * dev,struct acpi_battery_hook * hook)832 int devm_battery_hook_register(struct device *dev, struct acpi_battery_hook *hook)
833 {
834 	battery_hook_register(hook);
835 
836 	return devm_add_action_or_reset(dev, devm_battery_hook_unregister, hook);
837 }
838 EXPORT_SYMBOL_GPL(devm_battery_hook_register);
839 
840 /*
841  * This function gets called right after the battery sysfs
842  * attributes have been added, so that the drivers that
843  * define custom sysfs attributes can add their own.
844  */
battery_hook_add_battery(struct acpi_battery * battery)845 static void battery_hook_add_battery(struct acpi_battery *battery)
846 {
847 	struct acpi_battery_hook *hook_node, *tmp;
848 
849 	mutex_lock(&hook_mutex);
850 	INIT_LIST_HEAD(&battery->list);
851 	list_add(&battery->list, &acpi_battery_list);
852 	/*
853 	 * Since we added a new battery to the list, we need to
854 	 * iterate over the hooks and call add_battery for each
855 	 * hook that was registered. This usually happens
856 	 * when a battery gets hotplugged or initialized
857 	 * during the battery module initialization.
858 	 */
859 	list_for_each_entry_safe(hook_node, tmp, &battery_hook_list, list) {
860 		if (hook_node->add_battery(battery->bat, hook_node)) {
861 			/*
862 			 * The notification of the hook has failed, to
863 			 * prevent further errors we will unload the hook.
864 			 */
865 			pr_err("error in hook, unloading: %s",
866 					hook_node->name);
867 			battery_hook_unregister_unlocked(hook_node);
868 		}
869 	}
870 	mutex_unlock(&hook_mutex);
871 }
872 
battery_hook_remove_battery(struct acpi_battery * battery)873 static void battery_hook_remove_battery(struct acpi_battery *battery)
874 {
875 	struct acpi_battery_hook *hook;
876 
877 	mutex_lock(&hook_mutex);
878 	/*
879 	 * Before removing the hook, we need to remove all
880 	 * custom attributes from the battery.
881 	 */
882 	list_for_each_entry(hook, &battery_hook_list, list) {
883 		hook->remove_battery(battery->bat, hook);
884 	}
885 	/* Then, just remove the battery from the list */
886 	list_del(&battery->list);
887 	mutex_unlock(&hook_mutex);
888 }
889 
battery_hook_exit(void)890 static void __exit battery_hook_exit(void)
891 {
892 	struct acpi_battery_hook *hook;
893 	struct acpi_battery_hook *ptr;
894 	/*
895 	 * At this point, the acpi_bus_unregister_driver()
896 	 * has called remove for all batteries. We just
897 	 * need to remove the hooks.
898 	 */
899 	list_for_each_entry_safe(hook, ptr, &battery_hook_list, list) {
900 		battery_hook_unregister(hook);
901 	}
902 	mutex_destroy(&hook_mutex);
903 }
904 
sysfs_add_battery(struct acpi_battery * battery)905 static int sysfs_add_battery(struct acpi_battery *battery)
906 {
907 	struct power_supply_config psy_cfg = {
908 		.drv_data = battery,
909 		.attr_grp = acpi_battery_groups,
910 		.no_wakeup_source = true,
911 	};
912 	bool full_cap_broken = false;
913 	int power_unit;
914 
915 	scoped_guard(mutex, &battery->property_lock) {
916 		power_unit = battery->power_unit;
917 
918 		if (!ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity) &&
919 		    !ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity))
920 			full_cap_broken = true;
921 	}
922 
923 	if (power_unit == ACPI_BATTERY_POWER_UNIT_MA) {
924 		if (full_cap_broken) {
925 			battery->bat_desc.properties =
926 			    charge_battery_full_cap_broken_props;
927 			battery->bat_desc.num_properties =
928 			    ARRAY_SIZE(charge_battery_full_cap_broken_props);
929 		} else {
930 			battery->bat_desc.properties = charge_battery_props;
931 			battery->bat_desc.num_properties =
932 			    ARRAY_SIZE(charge_battery_props);
933 		}
934 	} else {
935 		if (full_cap_broken) {
936 			battery->bat_desc.properties =
937 			    energy_battery_full_cap_broken_props;
938 			battery->bat_desc.num_properties =
939 			    ARRAY_SIZE(energy_battery_full_cap_broken_props);
940 		} else {
941 			battery->bat_desc.properties = energy_battery_props;
942 			battery->bat_desc.num_properties =
943 			    ARRAY_SIZE(energy_battery_props);
944 		}
945 	}
946 
947 	battery->bat_desc.name = acpi_device_bid(battery->device);
948 	battery->bat_desc.type = POWER_SUPPLY_TYPE_BATTERY;
949 	battery->bat_desc.get_property = acpi_battery_get_property;
950 
951 	battery->bat = power_supply_register(&battery->device->dev,
952 				&battery->bat_desc, &psy_cfg);
953 
954 	if (IS_ERR(battery->bat)) {
955 		int result = PTR_ERR(battery->bat);
956 
957 		battery->bat = NULL;
958 		return result;
959 	}
960 	battery_hook_add_battery(battery);
961 	return 0;
962 }
963 
sysfs_remove_battery(struct acpi_battery * battery)964 static void sysfs_remove_battery(struct acpi_battery *battery)
965 {
966 	if (!battery->bat)
967 		return;
968 
969 	battery_hook_remove_battery(battery);
970 	power_supply_unregister(battery->bat);
971 	battery->bat = NULL;
972 }
973 
find_battery(const struct dmi_header * dm,void * private)974 static void find_battery(const struct dmi_header *dm, void *private)
975 {
976 	struct acpi_battery *battery = (struct acpi_battery *)private;
977 
978 	lockdep_assert_held(&battery->property_lock);
979 
980 	/* Note: the hardcoded offsets below have been extracted from
981 	 * the source code of dmidecode.
982 	 */
983 	if (dm->type == DMI_ENTRY_PORTABLE_BATTERY && dm->length >= 8) {
984 		const u8 *dmi_data = (const u8 *)(dm + 1);
985 		int dmi_capacity = get_unaligned((const u16 *)(dmi_data + 6));
986 
987 		if (dm->length >= 18)
988 			dmi_capacity *= dmi_data[17];
989 		if (battery->design_capacity * battery->design_voltage / 1000
990 		    != dmi_capacity &&
991 		    battery->design_capacity * 10 == dmi_capacity)
992 			set_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH,
993 				&battery->flags);
994 	}
995 }
996 
997 /*
998  * According to the ACPI spec, some kinds of primary batteries can
999  * report percentage battery remaining capacity directly to OS.
1000  * In this case, it reports the Last Full Charged Capacity == 100
1001  * and BatteryPresentRate == 0xFFFFFFFF.
1002  *
1003  * Now we found some battery reports percentage remaining capacity
1004  * even if it's rechargeable.
1005  * https://bugzilla.kernel.org/show_bug.cgi?id=15979
1006  *
1007  * Handle this correctly so that they won't break userspace.
1008  */
acpi_battery_quirks(struct acpi_battery * battery)1009 static void acpi_battery_quirks(struct acpi_battery *battery)
1010 {
1011 	lockdep_assert_held(&battery->property_lock);
1012 
1013 	if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags))
1014 		return;
1015 
1016 	if (battery->full_charge_capacity == 100 &&
1017 		battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN &&
1018 		battery->capacity_now >= 0 && battery->capacity_now <= 100) {
1019 		set_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags);
1020 		battery->full_charge_capacity = battery->design_capacity;
1021 		battery->capacity_now = (battery->capacity_now *
1022 				battery->full_charge_capacity) / 100;
1023 	}
1024 
1025 	if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH, &battery->flags))
1026 		return;
1027 
1028 	if (battery->power_unit && dmi_name_in_vendors("LENOVO")) {
1029 		const char *s;
1030 
1031 		s = dmi_get_system_info(DMI_PRODUCT_VERSION);
1032 		if (s && !strncasecmp(s, "ThinkPad", 8)) {
1033 			dmi_walk(find_battery, battery);
1034 			if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH,
1035 				     &battery->flags) &&
1036 			    battery->design_voltage) {
1037 				battery->design_capacity =
1038 				    battery->design_capacity *
1039 				    10000 / battery->design_voltage;
1040 				battery->full_charge_capacity =
1041 				    battery->full_charge_capacity *
1042 				    10000 / battery->design_voltage;
1043 				battery->design_capacity_warning =
1044 				    battery->design_capacity_warning *
1045 				    10000 / battery->design_voltage;
1046 				battery->capacity_now = battery->capacity_now *
1047 				    10000 / battery->design_voltage;
1048 			}
1049 		}
1050 	}
1051 
1052 	if (test_bit(ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE, &battery->flags))
1053 		return;
1054 
1055 	if (acpi_battery_is_degraded(battery) &&
1056 	    battery->capacity_now > battery->full_charge_capacity) {
1057 		set_bit(ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE, &battery->flags);
1058 		battery->capacity_now = battery->full_charge_capacity;
1059 	}
1060 }
1061 
acpi_battery_update(struct acpi_battery * battery,bool resume)1062 static int acpi_battery_update(struct acpi_battery *battery, bool resume)
1063 {
1064 	int result = acpi_battery_get_status(battery);
1065 	bool wakeup;
1066 
1067 	if (result)
1068 		return result;
1069 
1070 	if (!acpi_battery_present(battery)) {
1071 		sysfs_remove_battery(battery);
1072 		scoped_guard(mutex, &battery->property_lock)
1073 			battery->update_time = 0;
1074 		return 0;
1075 	}
1076 
1077 	if (resume)
1078 		return 0;
1079 
1080 	scoped_guard(mutex, &battery->property_lock) {
1081 		if (!battery->update_time) {
1082 			result = acpi_battery_get_info(battery);
1083 			if (result)
1084 				return result;
1085 			acpi_battery_init_alarm(battery);
1086 		}
1087 
1088 		result = acpi_battery_get_state(battery);
1089 		if (result)
1090 			return result;
1091 		acpi_battery_quirks(battery);
1092 
1093 		wakeup = ((battery->state & ACPI_BATTERY_STATE_CRITICAL) ||
1094 			  (test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags) &&
1095 			   (battery->capacity_now <= battery->alarm)));
1096 	}
1097 
1098 	if (!battery->bat) {
1099 		result = sysfs_add_battery(battery);
1100 		if (result)
1101 			return result;
1102 	}
1103 
1104 	/*
1105 	 * Wakeup the system if battery is critical low
1106 	 * or lower than the alarm level
1107 	 */
1108 	if (wakeup)
1109 		acpi_pm_wakeup_event(battery->phys_dev);
1110 
1111 	return result;
1112 }
1113 
acpi_battery_refresh(struct acpi_battery * battery)1114 static void acpi_battery_refresh(struct acpi_battery *battery)
1115 {
1116 	int power_unit;
1117 
1118 	if (!battery->bat)
1119 		return;
1120 
1121 	scoped_guard(mutex, &battery->property_lock) {
1122 		power_unit = battery->power_unit;
1123 
1124 		acpi_battery_get_info(battery);
1125 
1126 		if (power_unit == battery->power_unit)
1127 			return;
1128 	}
1129 
1130 	/* The battery has changed its reporting units. */
1131 	sysfs_remove_battery(battery);
1132 	sysfs_add_battery(battery);
1133 }
1134 
1135 /* Driver Interface */
acpi_battery_notification_worker(struct work_struct * work)1136 static void acpi_battery_notification_worker(struct work_struct *work)
1137 {
1138 	struct acpi_battery *battery = container_of(work, struct acpi_battery,
1139 						    acpi_notif_dwork.work);
1140 	struct acpi_device *device = battery->device;
1141 	u32 events[MAX_QUEUED_EVENTS];
1142 	struct power_supply *old;
1143 	unsigned int count, i;
1144 
1145 	guard(mutex)(&battery->update_lock);
1146 
1147 	count = kfifo_out(&battery->acpi_notif_fifo, events, sizeof(events));
1148 	count /= sizeof(events[0]);
1149 	if (!count)
1150 		return;
1151 
1152 	pr_debug("merged %u battery notifications within %dms\n", count, NOTIF_MERGING_MS);
1153 
1154 	old = battery->bat;
1155 	/*
1156 	 * On Acer Aspire V5-573G notifications are sometimes triggered too
1157 	 * early. For example, when AC is unplugged and notification is
1158 	 * triggered, battery state is still reported as "Full", and changes to
1159 	 * "Discharging" only after short delay, without any notification.
1160 	 */
1161 	if (battery_notification_delay_ms > 0)
1162 		msleep(battery_notification_delay_ms);
1163 
1164 	for (i = 0; i < count; i++) {
1165 		if (events[i] == ACPI_BATTERY_NOTIFY_INFO) {
1166 			acpi_battery_refresh(battery);
1167 			break;
1168 		}
1169 	}
1170 
1171 	acpi_battery_update(battery, false);
1172 
1173 	for (i = 0; i < count; i++) {
1174 		acpi_bus_generate_netlink_event(ACPI_BATTERY_CLASS,
1175 						dev_name(&device->dev), events[i],
1176 						acpi_battery_present(battery));
1177 		acpi_notifier_call_chain(ACPI_BATTERY_CLASS, acpi_device_bid(device),
1178 					 events[i], acpi_battery_present(battery));
1179 	}
1180 
1181 	/* acpi_battery_update could remove power_supply object */
1182 	if (old && battery->bat)
1183 		power_supply_changed(battery->bat);
1184 }
1185 
acpi_battery_notify(acpi_handle handle,u32 event,void * data)1186 static void acpi_battery_notify(acpi_handle handle, u32 event, void *data)
1187 {
1188 	struct acpi_battery *battery = data;
1189 
1190 	guard(mutex)(&battery->update_lock);
1191 
1192 	if (kfifo_avail(&battery->acpi_notif_fifo) >= sizeof(event)) {
1193 		kfifo_in(&battery->acpi_notif_fifo, &event, sizeof(event));
1194 		schedule_delayed_work(&battery->acpi_notif_dwork,
1195 				      msecs_to_jiffies(NOTIF_MERGING_MS));
1196 
1197 		return;
1198 	}
1199 
1200 	pr_err_ratelimited("too many battery notifications within %dms\n", NOTIF_MERGING_MS);
1201 }
1202 
battery_notify(struct notifier_block * nb,unsigned long mode,void * _unused)1203 static int battery_notify(struct notifier_block *nb,
1204 			  unsigned long mode, void *_unused)
1205 {
1206 	struct acpi_battery *battery = container_of(nb, struct acpi_battery,
1207 						    pm_nb);
1208 
1209 	if (mode == PM_POST_SUSPEND || mode == PM_POST_HIBERNATION) {
1210 		guard(mutex)(&battery->update_lock);
1211 
1212 		if (!acpi_battery_present(battery))
1213 			return 0;
1214 
1215 		if (battery->bat) {
1216 			acpi_battery_refresh(battery);
1217 		} else {
1218 			int result;
1219 
1220 			scoped_guard(mutex, &battery->property_lock) {
1221 				result = acpi_battery_get_info(battery);
1222 				if (result)
1223 					return result;
1224 			}
1225 
1226 			result = sysfs_add_battery(battery);
1227 			if (result)
1228 				return result;
1229 		}
1230 
1231 		scoped_guard(mutex, &battery->property_lock) {
1232 			acpi_battery_init_alarm(battery);
1233 			acpi_battery_get_state(battery);
1234 		}
1235 	}
1236 
1237 	return 0;
1238 }
1239 
1240 static int __init
battery_bix_broken_package_quirk(const struct dmi_system_id * d)1241 battery_bix_broken_package_quirk(const struct dmi_system_id *d)
1242 {
1243 	battery_bix_broken_package = 1;
1244 	return 0;
1245 }
1246 
1247 static int __init
battery_notification_delay_quirk(const struct dmi_system_id * d)1248 battery_notification_delay_quirk(const struct dmi_system_id *d)
1249 {
1250 	battery_notification_delay_ms = 1000;
1251 	return 0;
1252 }
1253 
1254 static int __init
battery_ac_is_broken_quirk(const struct dmi_system_id * d)1255 battery_ac_is_broken_quirk(const struct dmi_system_id *d)
1256 {
1257 	battery_ac_is_broken = 1;
1258 	return 0;
1259 }
1260 
1261 static const struct dmi_system_id bat_dmi_table[] __initconst = {
1262 	{
1263 		/* NEC LZ750/LS */
1264 		.callback = battery_bix_broken_package_quirk,
1265 		.matches = {
1266 			DMI_MATCH(DMI_SYS_VENDOR, "NEC"),
1267 			DMI_MATCH(DMI_PRODUCT_NAME, "PC-LZ750LS"),
1268 		},
1269 	},
1270 	{
1271 		/* Acer Aspire V5-573G */
1272 		.callback = battery_notification_delay_quirk,
1273 		.matches = {
1274 			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
1275 			DMI_MATCH(DMI_PRODUCT_NAME, "Aspire V5-573G"),
1276 		},
1277 	},
1278 	{
1279 		/* Point of View mobii wintab p800w */
1280 		.callback = battery_ac_is_broken_quirk,
1281 		.matches = {
1282 			DMI_MATCH(DMI_BOARD_VENDOR, "AMI Corporation"),
1283 			DMI_MATCH(DMI_BOARD_NAME, "Aptio CRB"),
1284 			DMI_MATCH(DMI_BIOS_VERSION, "3BAIR1013"),
1285 			/* Above matches are too generic, add bios-date match */
1286 			DMI_MATCH(DMI_BIOS_DATE, "08/22/2014"),
1287 		},
1288 	},
1289 	{
1290 		/* Microsoft Surface Go 3 */
1291 		.callback = battery_notification_delay_quirk,
1292 		.matches = {
1293 			DMI_MATCH(DMI_SYS_VENDOR, "Microsoft Corporation"),
1294 			DMI_MATCH(DMI_PRODUCT_NAME, "Surface Go 3"),
1295 		},
1296 	},
1297 	{},
1298 };
1299 
acpi_battery_wakeup_cleanup(void * data)1300 static void acpi_battery_wakeup_cleanup(void *data)
1301 {
1302 	device_init_wakeup(data, false);
1303 }
1304 
devm_acpi_battery_init_wakeup(struct device * dev)1305 static int devm_acpi_battery_init_wakeup(struct device *dev)
1306 {
1307 	device_init_wakeup(dev, true);
1308 	return devm_add_action_or_reset(dev, acpi_battery_wakeup_cleanup, dev);
1309 }
1310 
sysfs_battery_cleanup(void * data)1311 static void sysfs_battery_cleanup(void *data)
1312 {
1313 	struct acpi_battery *battery = data;
1314 
1315 	guard(mutex)(&battery->update_lock);
1316 
1317 	sysfs_remove_battery(battery);
1318 }
1319 
1320 /*
1321  * Some machines'(E,G Lenovo Z480) ECs are not stable
1322  * during boot up and this causes battery driver fails to be
1323  * probed due to failure of getting battery information
1324  * from EC sometimes. After several retries, the operation
1325  * may work. So add retry code here and 20ms sleep between
1326  * every retries.
1327  */
devm_acpi_battery_update_retry(struct device * dev,struct acpi_battery * battery)1328 static int devm_acpi_battery_update_retry(struct device *dev,
1329 					  struct acpi_battery *battery)
1330 {
1331 	int retry, ret;
1332 
1333 	ret = devm_add_action(dev, sysfs_battery_cleanup, battery);
1334 	if (ret)
1335 		return ret;
1336 
1337 	guard(mutex)(&battery->update_lock);
1338 
1339 	for (retry = 5; retry; retry--) {
1340 		ret = acpi_battery_update(battery, false);
1341 		if (!ret)
1342 			break;
1343 
1344 		msleep(20);
1345 	}
1346 	return ret;
1347 }
1348 
acpi_battery_notify_dwork_cleanup(void * data)1349 static void acpi_battery_notify_dwork_cleanup(void *data)
1350 {
1351 	struct acpi_battery *battery = data;
1352 
1353 	cancel_delayed_work_sync(&battery->acpi_notif_dwork);
1354 	kfifo_free(&battery->acpi_notif_fifo);
1355 }
1356 
devm_acpi_battery_init_notify_dwork(struct device * dev,struct acpi_battery * battery)1357 static int devm_acpi_battery_init_notify_dwork(struct device *dev,
1358 					       struct acpi_battery *battery)
1359 {
1360 	int ret;
1361 
1362 	INIT_DELAYED_WORK(&battery->acpi_notif_dwork, acpi_battery_notification_worker);
1363 
1364 	ret = kfifo_alloc(&battery->acpi_notif_fifo,
1365 			  MAX_QUEUED_EVENTS * sizeof(u32), GFP_KERNEL);
1366 	if (ret)
1367 		return ret;
1368 
1369 	return devm_add_action_or_reset(dev, acpi_battery_notify_dwork_cleanup, battery);
1370 }
1371 
acpi_battery_probe(struct platform_device * pdev)1372 static int acpi_battery_probe(struct platform_device *pdev)
1373 {
1374 	struct device *dev = &pdev->dev;
1375 	struct acpi_battery *battery;
1376 	struct acpi_device *device;
1377 	int result;
1378 
1379 	device = ACPI_COMPANION(dev);
1380 	if (!device)
1381 		return -ENODEV;
1382 
1383 	if (device->dep_unmet)
1384 		return -EPROBE_DEFER;
1385 
1386 	battery = devm_kzalloc(dev, sizeof(*battery), GFP_KERNEL);
1387 	if (!battery)
1388 		return -ENOMEM;
1389 
1390 	platform_set_drvdata(pdev, battery);
1391 
1392 	battery->phys_dev = &pdev->dev;
1393 	battery->device = device;
1394 
1395 	result = devm_mutex_init(dev, &battery->update_lock);
1396 	if (result)
1397 		return result;
1398 
1399 	result = devm_mutex_init(&pdev->dev, &battery->property_lock);
1400 	if (result)
1401 		return result;
1402 
1403 	if (acpi_has_method(battery->device->handle, "_BIX"))
1404 		set_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags);
1405 
1406 	result = devm_acpi_battery_update_retry(dev, battery);
1407 	if (result)
1408 		return result;
1409 
1410 	pr_info("Slot [%s] (battery %s)\n", acpi_device_bid(device),
1411 		device->status.battery_present ? "present" : "absent");
1412 
1413 	result = devm_acpi_battery_init_wakeup(dev);
1414 	if (result)
1415 		return result;
1416 
1417 	result = devm_acpi_battery_init_notify_dwork(dev, battery);
1418 	if (result)
1419 		return result;
1420 
1421 	result = devm_acpi_install_notify_handler(dev, ACPI_ALL_NOTIFY,
1422 						  acpi_battery_notify, battery);
1423 	if (result)
1424 		return result;
1425 
1426 	battery->pm_nb.notifier_call = battery_notify;
1427 	return register_pm_notifier(&battery->pm_nb);
1428 }
1429 
acpi_battery_remove(struct platform_device * pdev)1430 static void acpi_battery_remove(struct platform_device *pdev)
1431 {
1432 	struct acpi_battery *battery = platform_get_drvdata(pdev);
1433 
1434 	unregister_pm_notifier(&battery->pm_nb);
1435 }
1436 
1437 /* this is needed to learn about changes made in suspended state */
acpi_battery_resume(struct device * dev)1438 static int acpi_battery_resume(struct device *dev)
1439 {
1440 	struct acpi_battery *battery = dev_get_drvdata(dev);
1441 
1442 	if (!battery)
1443 		return -EINVAL;
1444 
1445 	battery->update_time = 0;
1446 
1447 	guard(mutex)(&battery->update_lock);
1448 
1449 	acpi_battery_update(battery, true);
1450 	return 0;
1451 }
1452 
1453 static DEFINE_SIMPLE_DEV_PM_OPS(acpi_battery_pm, NULL, acpi_battery_resume);
1454 
1455 static struct platform_driver acpi_battery_driver = {
1456 	.probe = acpi_battery_probe,
1457 	.remove = acpi_battery_remove,
1458 	.driver = {
1459 		.name = "acpi-battery",
1460 		.acpi_match_table = battery_device_ids,
1461 		.pm = pm_sleep_ptr(&acpi_battery_pm),
1462 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1463 	},
1464 };
1465 
acpi_battery_init(void)1466 static int __init acpi_battery_init(void)
1467 {
1468 	if (acpi_disabled || acpi_quirk_skip_acpi_ac_and_battery())
1469 		return -ENODEV;
1470 
1471 	dmi_check_system(bat_dmi_table);
1472 
1473 	return platform_driver_register(&acpi_battery_driver);
1474 }
1475 
acpi_battery_exit(void)1476 static void __exit acpi_battery_exit(void)
1477 {
1478 	platform_driver_unregister(&acpi_battery_driver);
1479 	battery_hook_exit();
1480 }
1481 
1482 module_init(acpi_battery_init);
1483 module_exit(acpi_battery_exit);
1484