xref: /linux/drivers/acpi/battery.c (revision 492c826b9facefa84995f4dea917e301b5ee0884)
1 /*
2  *  battery.c - ACPI Battery Driver (Revision: 2.0)
3  *
4  *  Copyright (C) 2007 Alexey Starikovskiy <astarikovskiy@suse.de>
5  *  Copyright (C) 2004-2007 Vladimir Lebedev <vladimir.p.lebedev@intel.com>
6  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
7  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
8  *
9  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
10  *
11  *  This program is free software; you can redistribute it and/or modify
12  *  it under the terms of the GNU General Public License as published by
13  *  the Free Software Foundation; either version 2 of the License, or (at
14  *  your option) any later version.
15  *
16  *  This program is distributed in the hope that it will be useful, but
17  *  WITHOUT ANY WARRANTY; without even the implied warranty of
18  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
19  *  General Public License for more details.
20  *
21  *  You should have received a copy of the GNU General Public License along
22  *  with this program; if not, write to the Free Software Foundation, Inc.,
23  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
24  *
25  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
26  */
27 
28 #include <linux/kernel.h>
29 #include <linux/module.h>
30 #include <linux/init.h>
31 #include <linux/types.h>
32 #include <linux/jiffies.h>
33 #include <linux/async.h>
34 #include <linux/dmi.h>
35 #include <linux/slab.h>
36 #include <linux/suspend.h>
37 
38 #ifdef CONFIG_ACPI_PROCFS_POWER
39 #include <linux/proc_fs.h>
40 #include <linux/seq_file.h>
41 #include <asm/uaccess.h>
42 #endif
43 
44 #include <acpi/acpi_bus.h>
45 #include <acpi/acpi_drivers.h>
46 #include <linux/power_supply.h>
47 
48 #define PREFIX "ACPI: "
49 
50 #define ACPI_BATTERY_VALUE_UNKNOWN 0xFFFFFFFF
51 
52 #define ACPI_BATTERY_CLASS		"battery"
53 #define ACPI_BATTERY_DEVICE_NAME	"Battery"
54 #define ACPI_BATTERY_NOTIFY_STATUS	0x80
55 #define ACPI_BATTERY_NOTIFY_INFO	0x81
56 #define ACPI_BATTERY_NOTIFY_THRESHOLD   0x82
57 
58 #define _COMPONENT		ACPI_BATTERY_COMPONENT
59 
60 ACPI_MODULE_NAME("battery");
61 
62 MODULE_AUTHOR("Paul Diefenbaugh");
63 MODULE_AUTHOR("Alexey Starikovskiy <astarikovskiy@suse.de>");
64 MODULE_DESCRIPTION("ACPI Battery Driver");
65 MODULE_LICENSE("GPL");
66 
67 static unsigned int cache_time = 1000;
68 module_param(cache_time, uint, 0644);
69 MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
70 
71 #ifdef CONFIG_ACPI_PROCFS_POWER
72 extern struct proc_dir_entry *acpi_lock_battery_dir(void);
73 extern void *acpi_unlock_battery_dir(struct proc_dir_entry *acpi_battery_dir);
74 
75 enum acpi_battery_files {
76 	info_tag = 0,
77 	state_tag,
78 	alarm_tag,
79 	ACPI_BATTERY_NUMFILES,
80 };
81 
82 #endif
83 
84 static const struct acpi_device_id battery_device_ids[] = {
85 	{"PNP0C0A", 0},
86 	{"", 0},
87 };
88 
89 MODULE_DEVICE_TABLE(acpi, battery_device_ids);
90 
91 enum {
92 	ACPI_BATTERY_ALARM_PRESENT,
93 	ACPI_BATTERY_XINFO_PRESENT,
94 	/* For buggy DSDTs that report negative 16-bit values for either
95 	 * charging or discharging current and/or report 0 as 65536
96 	 * due to bad math.
97 	 */
98 	ACPI_BATTERY_QUIRK_SIGNED16_CURRENT,
99 	ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY,
100 };
101 
102 struct acpi_battery {
103 	struct mutex lock;
104 	struct power_supply bat;
105 	struct acpi_device *device;
106 	struct notifier_block pm_nb;
107 	unsigned long update_time;
108 	int rate_now;
109 	int capacity_now;
110 	int voltage_now;
111 	int design_capacity;
112 	int full_charge_capacity;
113 	int technology;
114 	int design_voltage;
115 	int design_capacity_warning;
116 	int design_capacity_low;
117 	int cycle_count;
118 	int measurement_accuracy;
119 	int max_sampling_time;
120 	int min_sampling_time;
121 	int max_averaging_interval;
122 	int min_averaging_interval;
123 	int capacity_granularity_1;
124 	int capacity_granularity_2;
125 	int alarm;
126 	char model_number[32];
127 	char serial_number[32];
128 	char type[32];
129 	char oem_info[32];
130 	int state;
131 	int power_unit;
132 	unsigned long flags;
133 };
134 
135 #define to_acpi_battery(x) container_of(x, struct acpi_battery, bat);
136 
137 inline int acpi_battery_present(struct acpi_battery *battery)
138 {
139 	return battery->device->status.battery_present;
140 }
141 
142 static int acpi_battery_technology(struct acpi_battery *battery)
143 {
144 	if (!strcasecmp("NiCd", battery->type))
145 		return POWER_SUPPLY_TECHNOLOGY_NiCd;
146 	if (!strcasecmp("NiMH", battery->type))
147 		return POWER_SUPPLY_TECHNOLOGY_NiMH;
148 	if (!strcasecmp("LION", battery->type))
149 		return POWER_SUPPLY_TECHNOLOGY_LION;
150 	if (!strncasecmp("LI-ION", battery->type, 6))
151 		return POWER_SUPPLY_TECHNOLOGY_LION;
152 	if (!strcasecmp("LiP", battery->type))
153 		return POWER_SUPPLY_TECHNOLOGY_LIPO;
154 	return POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
155 }
156 
157 static int acpi_battery_get_state(struct acpi_battery *battery);
158 
159 static int acpi_battery_is_charged(struct acpi_battery *battery)
160 {
161 	/* either charging or discharging */
162 	if (battery->state != 0)
163 		return 0;
164 
165 	/* battery not reporting charge */
166 	if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN ||
167 	    battery->capacity_now == 0)
168 		return 0;
169 
170 	/* good batteries update full_charge as the batteries degrade */
171 	if (battery->full_charge_capacity == battery->capacity_now)
172 		return 1;
173 
174 	/* fallback to using design values for broken batteries */
175 	if (battery->design_capacity == battery->capacity_now)
176 		return 1;
177 
178 	/* we don't do any sort of metric based on percentages */
179 	return 0;
180 }
181 
182 static int acpi_battery_get_property(struct power_supply *psy,
183 				     enum power_supply_property psp,
184 				     union power_supply_propval *val)
185 {
186 	int ret = 0;
187 	struct acpi_battery *battery = to_acpi_battery(psy);
188 
189 	if (acpi_battery_present(battery)) {
190 		/* run battery update only if it is present */
191 		acpi_battery_get_state(battery);
192 	} else if (psp != POWER_SUPPLY_PROP_PRESENT)
193 		return -ENODEV;
194 	switch (psp) {
195 	case POWER_SUPPLY_PROP_STATUS:
196 		if (battery->state & 0x01)
197 			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
198 		else if (battery->state & 0x02)
199 			val->intval = POWER_SUPPLY_STATUS_CHARGING;
200 		else if (acpi_battery_is_charged(battery))
201 			val->intval = POWER_SUPPLY_STATUS_FULL;
202 		else
203 			val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
204 		break;
205 	case POWER_SUPPLY_PROP_PRESENT:
206 		val->intval = acpi_battery_present(battery);
207 		break;
208 	case POWER_SUPPLY_PROP_TECHNOLOGY:
209 		val->intval = acpi_battery_technology(battery);
210 		break;
211 	case POWER_SUPPLY_PROP_CYCLE_COUNT:
212 		val->intval = battery->cycle_count;
213 		break;
214 	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
215 		if (battery->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
216 			ret = -ENODEV;
217 		else
218 			val->intval = battery->design_voltage * 1000;
219 		break;
220 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
221 		if (battery->voltage_now == ACPI_BATTERY_VALUE_UNKNOWN)
222 			ret = -ENODEV;
223 		else
224 			val->intval = battery->voltage_now * 1000;
225 		break;
226 	case POWER_SUPPLY_PROP_CURRENT_NOW:
227 	case POWER_SUPPLY_PROP_POWER_NOW:
228 		if (battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN)
229 			ret = -ENODEV;
230 		else
231 			val->intval = battery->rate_now * 1000;
232 		break;
233 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
234 	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
235 		if (battery->design_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
236 			ret = -ENODEV;
237 		else
238 			val->intval = battery->design_capacity * 1000;
239 		break;
240 	case POWER_SUPPLY_PROP_CHARGE_FULL:
241 	case POWER_SUPPLY_PROP_ENERGY_FULL:
242 		if (battery->full_charge_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
243 			ret = -ENODEV;
244 		else
245 			val->intval = battery->full_charge_capacity * 1000;
246 		break;
247 	case POWER_SUPPLY_PROP_CHARGE_NOW:
248 	case POWER_SUPPLY_PROP_ENERGY_NOW:
249 		if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN)
250 			ret = -ENODEV;
251 		else
252 			val->intval = battery->capacity_now * 1000;
253 		break;
254 	case POWER_SUPPLY_PROP_MODEL_NAME:
255 		val->strval = battery->model_number;
256 		break;
257 	case POWER_SUPPLY_PROP_MANUFACTURER:
258 		val->strval = battery->oem_info;
259 		break;
260 	case POWER_SUPPLY_PROP_SERIAL_NUMBER:
261 		val->strval = battery->serial_number;
262 		break;
263 	default:
264 		ret = -EINVAL;
265 	}
266 	return ret;
267 }
268 
269 static enum power_supply_property charge_battery_props[] = {
270 	POWER_SUPPLY_PROP_STATUS,
271 	POWER_SUPPLY_PROP_PRESENT,
272 	POWER_SUPPLY_PROP_TECHNOLOGY,
273 	POWER_SUPPLY_PROP_CYCLE_COUNT,
274 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
275 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
276 	POWER_SUPPLY_PROP_CURRENT_NOW,
277 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
278 	POWER_SUPPLY_PROP_CHARGE_FULL,
279 	POWER_SUPPLY_PROP_CHARGE_NOW,
280 	POWER_SUPPLY_PROP_MODEL_NAME,
281 	POWER_SUPPLY_PROP_MANUFACTURER,
282 	POWER_SUPPLY_PROP_SERIAL_NUMBER,
283 };
284 
285 static enum power_supply_property energy_battery_props[] = {
286 	POWER_SUPPLY_PROP_STATUS,
287 	POWER_SUPPLY_PROP_PRESENT,
288 	POWER_SUPPLY_PROP_TECHNOLOGY,
289 	POWER_SUPPLY_PROP_CYCLE_COUNT,
290 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
291 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
292 	POWER_SUPPLY_PROP_POWER_NOW,
293 	POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
294 	POWER_SUPPLY_PROP_ENERGY_FULL,
295 	POWER_SUPPLY_PROP_ENERGY_NOW,
296 	POWER_SUPPLY_PROP_MODEL_NAME,
297 	POWER_SUPPLY_PROP_MANUFACTURER,
298 	POWER_SUPPLY_PROP_SERIAL_NUMBER,
299 };
300 
301 #ifdef CONFIG_ACPI_PROCFS_POWER
302 inline char *acpi_battery_units(struct acpi_battery *battery)
303 {
304 	return (battery->power_unit)?"mA":"mW";
305 }
306 #endif
307 
308 /* --------------------------------------------------------------------------
309                                Battery Management
310    -------------------------------------------------------------------------- */
311 struct acpi_offsets {
312 	size_t offset;		/* offset inside struct acpi_sbs_battery */
313 	u8 mode;		/* int or string? */
314 };
315 
316 static struct acpi_offsets state_offsets[] = {
317 	{offsetof(struct acpi_battery, state), 0},
318 	{offsetof(struct acpi_battery, rate_now), 0},
319 	{offsetof(struct acpi_battery, capacity_now), 0},
320 	{offsetof(struct acpi_battery, voltage_now), 0},
321 };
322 
323 static struct acpi_offsets info_offsets[] = {
324 	{offsetof(struct acpi_battery, power_unit), 0},
325 	{offsetof(struct acpi_battery, design_capacity), 0},
326 	{offsetof(struct acpi_battery, full_charge_capacity), 0},
327 	{offsetof(struct acpi_battery, technology), 0},
328 	{offsetof(struct acpi_battery, design_voltage), 0},
329 	{offsetof(struct acpi_battery, design_capacity_warning), 0},
330 	{offsetof(struct acpi_battery, design_capacity_low), 0},
331 	{offsetof(struct acpi_battery, capacity_granularity_1), 0},
332 	{offsetof(struct acpi_battery, capacity_granularity_2), 0},
333 	{offsetof(struct acpi_battery, model_number), 1},
334 	{offsetof(struct acpi_battery, serial_number), 1},
335 	{offsetof(struct acpi_battery, type), 1},
336 	{offsetof(struct acpi_battery, oem_info), 1},
337 };
338 
339 static struct acpi_offsets extended_info_offsets[] = {
340 	{offsetof(struct acpi_battery, power_unit), 0},
341 	{offsetof(struct acpi_battery, design_capacity), 0},
342 	{offsetof(struct acpi_battery, full_charge_capacity), 0},
343 	{offsetof(struct acpi_battery, technology), 0},
344 	{offsetof(struct acpi_battery, design_voltage), 0},
345 	{offsetof(struct acpi_battery, design_capacity_warning), 0},
346 	{offsetof(struct acpi_battery, design_capacity_low), 0},
347 	{offsetof(struct acpi_battery, cycle_count), 0},
348 	{offsetof(struct acpi_battery, measurement_accuracy), 0},
349 	{offsetof(struct acpi_battery, max_sampling_time), 0},
350 	{offsetof(struct acpi_battery, min_sampling_time), 0},
351 	{offsetof(struct acpi_battery, max_averaging_interval), 0},
352 	{offsetof(struct acpi_battery, min_averaging_interval), 0},
353 	{offsetof(struct acpi_battery, capacity_granularity_1), 0},
354 	{offsetof(struct acpi_battery, capacity_granularity_2), 0},
355 	{offsetof(struct acpi_battery, model_number), 1},
356 	{offsetof(struct acpi_battery, serial_number), 1},
357 	{offsetof(struct acpi_battery, type), 1},
358 	{offsetof(struct acpi_battery, oem_info), 1},
359 };
360 
361 static int extract_package(struct acpi_battery *battery,
362 			   union acpi_object *package,
363 			   struct acpi_offsets *offsets, int num)
364 {
365 	int i;
366 	union acpi_object *element;
367 	if (package->type != ACPI_TYPE_PACKAGE)
368 		return -EFAULT;
369 	for (i = 0; i < num; ++i) {
370 		if (package->package.count <= i)
371 			return -EFAULT;
372 		element = &package->package.elements[i];
373 		if (offsets[i].mode) {
374 			u8 *ptr = (u8 *)battery + offsets[i].offset;
375 			if (element->type == ACPI_TYPE_STRING ||
376 			    element->type == ACPI_TYPE_BUFFER)
377 				strncpy(ptr, element->string.pointer, 32);
378 			else if (element->type == ACPI_TYPE_INTEGER) {
379 				strncpy(ptr, (u8 *)&element->integer.value,
380 					sizeof(u64));
381 				ptr[sizeof(u64)] = 0;
382 			} else
383 				*ptr = 0; /* don't have value */
384 		} else {
385 			int *x = (int *)((u8 *)battery + offsets[i].offset);
386 			*x = (element->type == ACPI_TYPE_INTEGER) ?
387 				element->integer.value : -1;
388 		}
389 	}
390 	return 0;
391 }
392 
393 static int acpi_battery_get_status(struct acpi_battery *battery)
394 {
395 	if (acpi_bus_get_status(battery->device)) {
396 		ACPI_EXCEPTION((AE_INFO, AE_ERROR, "Evaluating _STA"));
397 		return -ENODEV;
398 	}
399 	return 0;
400 }
401 
402 static int acpi_battery_get_info(struct acpi_battery *battery)
403 {
404 	int result = -EFAULT;
405 	acpi_status status = 0;
406 	char *name = test_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags)?
407 			"_BIX" : "_BIF";
408 
409 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
410 
411 	if (!acpi_battery_present(battery))
412 		return 0;
413 	mutex_lock(&battery->lock);
414 	status = acpi_evaluate_object(battery->device->handle, name,
415 						NULL, &buffer);
416 	mutex_unlock(&battery->lock);
417 
418 	if (ACPI_FAILURE(status)) {
419 		ACPI_EXCEPTION((AE_INFO, status, "Evaluating %s", name));
420 		return -ENODEV;
421 	}
422 	if (test_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags))
423 		result = extract_package(battery, buffer.pointer,
424 				extended_info_offsets,
425 				ARRAY_SIZE(extended_info_offsets));
426 	else
427 		result = extract_package(battery, buffer.pointer,
428 				info_offsets, ARRAY_SIZE(info_offsets));
429 	kfree(buffer.pointer);
430 	if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags))
431 		battery->full_charge_capacity = battery->design_capacity;
432 	return result;
433 }
434 
435 static int acpi_battery_get_state(struct acpi_battery *battery)
436 {
437 	int result = 0;
438 	acpi_status status = 0;
439 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
440 
441 	if (!acpi_battery_present(battery))
442 		return 0;
443 
444 	if (battery->update_time &&
445 	    time_before(jiffies, battery->update_time +
446 			msecs_to_jiffies(cache_time)))
447 		return 0;
448 
449 	mutex_lock(&battery->lock);
450 	status = acpi_evaluate_object(battery->device->handle, "_BST",
451 				      NULL, &buffer);
452 	mutex_unlock(&battery->lock);
453 
454 	if (ACPI_FAILURE(status)) {
455 		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BST"));
456 		return -ENODEV;
457 	}
458 
459 	result = extract_package(battery, buffer.pointer,
460 				 state_offsets, ARRAY_SIZE(state_offsets));
461 	battery->update_time = jiffies;
462 	kfree(buffer.pointer);
463 
464 	if (test_bit(ACPI_BATTERY_QUIRK_SIGNED16_CURRENT, &battery->flags) &&
465 	    battery->rate_now != -1)
466 		battery->rate_now = abs((s16)battery->rate_now);
467 
468 	if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags)
469 	    && battery->capacity_now >= 0 && battery->capacity_now <= 100)
470 		battery->capacity_now = (battery->capacity_now *
471 				battery->full_charge_capacity) / 100;
472 	return result;
473 }
474 
475 static int acpi_battery_set_alarm(struct acpi_battery *battery)
476 {
477 	acpi_status status = 0;
478 	union acpi_object arg0 = { .type = ACPI_TYPE_INTEGER };
479 	struct acpi_object_list arg_list = { 1, &arg0 };
480 
481 	if (!acpi_battery_present(battery) ||
482 	    !test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags))
483 		return -ENODEV;
484 
485 	arg0.integer.value = battery->alarm;
486 
487 	mutex_lock(&battery->lock);
488 	status = acpi_evaluate_object(battery->device->handle, "_BTP",
489 				 &arg_list, NULL);
490 	mutex_unlock(&battery->lock);
491 
492 	if (ACPI_FAILURE(status))
493 		return -ENODEV;
494 
495 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Alarm set to %d\n", battery->alarm));
496 	return 0;
497 }
498 
499 static int acpi_battery_init_alarm(struct acpi_battery *battery)
500 {
501 	acpi_status status = AE_OK;
502 	acpi_handle handle = NULL;
503 
504 	/* See if alarms are supported, and if so, set default */
505 	status = acpi_get_handle(battery->device->handle, "_BTP", &handle);
506 	if (ACPI_FAILURE(status)) {
507 		clear_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags);
508 		return 0;
509 	}
510 	set_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags);
511 	if (!battery->alarm)
512 		battery->alarm = battery->design_capacity_warning;
513 	return acpi_battery_set_alarm(battery);
514 }
515 
516 static ssize_t acpi_battery_alarm_show(struct device *dev,
517 					struct device_attribute *attr,
518 					char *buf)
519 {
520 	struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
521 	return sprintf(buf, "%d\n", battery->alarm * 1000);
522 }
523 
524 static ssize_t acpi_battery_alarm_store(struct device *dev,
525 					struct device_attribute *attr,
526 					const char *buf, size_t count)
527 {
528 	unsigned long x;
529 	struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
530 	if (sscanf(buf, "%ld\n", &x) == 1)
531 		battery->alarm = x/1000;
532 	if (acpi_battery_present(battery))
533 		acpi_battery_set_alarm(battery);
534 	return count;
535 }
536 
537 static struct device_attribute alarm_attr = {
538 	.attr = {.name = "alarm", .mode = 0644},
539 	.show = acpi_battery_alarm_show,
540 	.store = acpi_battery_alarm_store,
541 };
542 
543 static int sysfs_add_battery(struct acpi_battery *battery)
544 {
545 	int result;
546 
547 	if (battery->power_unit) {
548 		battery->bat.properties = charge_battery_props;
549 		battery->bat.num_properties =
550 			ARRAY_SIZE(charge_battery_props);
551 	} else {
552 		battery->bat.properties = energy_battery_props;
553 		battery->bat.num_properties =
554 			ARRAY_SIZE(energy_battery_props);
555 	}
556 
557 	battery->bat.name = acpi_device_bid(battery->device);
558 	battery->bat.type = POWER_SUPPLY_TYPE_BATTERY;
559 	battery->bat.get_property = acpi_battery_get_property;
560 
561 	result = power_supply_register(&battery->device->dev, &battery->bat);
562 	if (result)
563 		return result;
564 	return device_create_file(battery->bat.dev, &alarm_attr);
565 }
566 
567 static void sysfs_remove_battery(struct acpi_battery *battery)
568 {
569 	if (!battery->bat.dev)
570 		return;
571 	device_remove_file(battery->bat.dev, &alarm_attr);
572 	power_supply_unregister(&battery->bat);
573 	battery->bat.dev = NULL;
574 }
575 
576 static void acpi_battery_quirks(struct acpi_battery *battery)
577 {
578 	if (dmi_name_in_vendors("Acer") && battery->power_unit) {
579 		set_bit(ACPI_BATTERY_QUIRK_SIGNED16_CURRENT, &battery->flags);
580 	}
581 }
582 
583 /*
584  * According to the ACPI spec, some kinds of primary batteries can
585  * report percentage battery remaining capacity directly to OS.
586  * In this case, it reports the Last Full Charged Capacity == 100
587  * and BatteryPresentRate == 0xFFFFFFFF.
588  *
589  * Now we found some battery reports percentage remaining capacity
590  * even if it's rechargeable.
591  * https://bugzilla.kernel.org/show_bug.cgi?id=15979
592  *
593  * Handle this correctly so that they won't break userspace.
594  */
595 static void acpi_battery_quirks2(struct acpi_battery *battery)
596 {
597 	if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags))
598 		return ;
599 
600         if (battery->full_charge_capacity == 100 &&
601             battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN &&
602             battery->capacity_now >=0 && battery->capacity_now <= 100) {
603 		set_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags);
604 		battery->full_charge_capacity = battery->design_capacity;
605 		battery->capacity_now = (battery->capacity_now *
606 				battery->full_charge_capacity) / 100;
607 	}
608 }
609 
610 static int acpi_battery_update(struct acpi_battery *battery)
611 {
612 	int result, old_present = acpi_battery_present(battery);
613 	result = acpi_battery_get_status(battery);
614 	if (result)
615 		return result;
616 	if (!acpi_battery_present(battery)) {
617 		sysfs_remove_battery(battery);
618 		battery->update_time = 0;
619 		return 0;
620 	}
621 	if (!battery->update_time ||
622 	    old_present != acpi_battery_present(battery)) {
623 		result = acpi_battery_get_info(battery);
624 		if (result)
625 			return result;
626 		acpi_battery_quirks(battery);
627 		acpi_battery_init_alarm(battery);
628 	}
629 	if (!battery->bat.dev)
630 		sysfs_add_battery(battery);
631 	result = acpi_battery_get_state(battery);
632 	acpi_battery_quirks2(battery);
633 	return result;
634 }
635 
636 static void acpi_battery_refresh(struct acpi_battery *battery)
637 {
638 	if (!battery->bat.dev)
639 		return;
640 
641 	acpi_battery_get_info(battery);
642 	/* The battery may have changed its reporting units. */
643 	sysfs_remove_battery(battery);
644 	sysfs_add_battery(battery);
645 }
646 
647 /* --------------------------------------------------------------------------
648                               FS Interface (/proc)
649    -------------------------------------------------------------------------- */
650 
651 #ifdef CONFIG_ACPI_PROCFS_POWER
652 static struct proc_dir_entry *acpi_battery_dir;
653 
654 static int acpi_battery_print_info(struct seq_file *seq, int result)
655 {
656 	struct acpi_battery *battery = seq->private;
657 
658 	if (result)
659 		goto end;
660 
661 	seq_printf(seq, "present:                 %s\n",
662 		   acpi_battery_present(battery)?"yes":"no");
663 	if (!acpi_battery_present(battery))
664 		goto end;
665 	if (battery->design_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
666 		seq_printf(seq, "design capacity:         unknown\n");
667 	else
668 		seq_printf(seq, "design capacity:         %d %sh\n",
669 			   battery->design_capacity,
670 			   acpi_battery_units(battery));
671 
672 	if (battery->full_charge_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
673 		seq_printf(seq, "last full capacity:      unknown\n");
674 	else
675 		seq_printf(seq, "last full capacity:      %d %sh\n",
676 			   battery->full_charge_capacity,
677 			   acpi_battery_units(battery));
678 
679 	seq_printf(seq, "battery technology:      %srechargeable\n",
680 		   (!battery->technology)?"non-":"");
681 
682 	if (battery->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
683 		seq_printf(seq, "design voltage:          unknown\n");
684 	else
685 		seq_printf(seq, "design voltage:          %d mV\n",
686 			   battery->design_voltage);
687 	seq_printf(seq, "design capacity warning: %d %sh\n",
688 		   battery->design_capacity_warning,
689 		   acpi_battery_units(battery));
690 	seq_printf(seq, "design capacity low:     %d %sh\n",
691 		   battery->design_capacity_low,
692 		   acpi_battery_units(battery));
693 	seq_printf(seq, "cycle count:		  %i\n", battery->cycle_count);
694 	seq_printf(seq, "capacity granularity 1:  %d %sh\n",
695 		   battery->capacity_granularity_1,
696 		   acpi_battery_units(battery));
697 	seq_printf(seq, "capacity granularity 2:  %d %sh\n",
698 		   battery->capacity_granularity_2,
699 		   acpi_battery_units(battery));
700 	seq_printf(seq, "model number:            %s\n", battery->model_number);
701 	seq_printf(seq, "serial number:           %s\n", battery->serial_number);
702 	seq_printf(seq, "battery type:            %s\n", battery->type);
703 	seq_printf(seq, "OEM info:                %s\n", battery->oem_info);
704       end:
705 	if (result)
706 		seq_printf(seq, "ERROR: Unable to read battery info\n");
707 	return result;
708 }
709 
710 static int acpi_battery_print_state(struct seq_file *seq, int result)
711 {
712 	struct acpi_battery *battery = seq->private;
713 
714 	if (result)
715 		goto end;
716 
717 	seq_printf(seq, "present:                 %s\n",
718 		   acpi_battery_present(battery)?"yes":"no");
719 	if (!acpi_battery_present(battery))
720 		goto end;
721 
722 	seq_printf(seq, "capacity state:          %s\n",
723 			(battery->state & 0x04)?"critical":"ok");
724 	if ((battery->state & 0x01) && (battery->state & 0x02))
725 		seq_printf(seq,
726 			   "charging state:          charging/discharging\n");
727 	else if (battery->state & 0x01)
728 		seq_printf(seq, "charging state:          discharging\n");
729 	else if (battery->state & 0x02)
730 		seq_printf(seq, "charging state:          charging\n");
731 	else
732 		seq_printf(seq, "charging state:          charged\n");
733 
734 	if (battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN)
735 		seq_printf(seq, "present rate:            unknown\n");
736 	else
737 		seq_printf(seq, "present rate:            %d %s\n",
738 			   battery->rate_now, acpi_battery_units(battery));
739 
740 	if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN)
741 		seq_printf(seq, "remaining capacity:      unknown\n");
742 	else
743 		seq_printf(seq, "remaining capacity:      %d %sh\n",
744 			   battery->capacity_now, acpi_battery_units(battery));
745 	if (battery->voltage_now == ACPI_BATTERY_VALUE_UNKNOWN)
746 		seq_printf(seq, "present voltage:         unknown\n");
747 	else
748 		seq_printf(seq, "present voltage:         %d mV\n",
749 			   battery->voltage_now);
750       end:
751 	if (result)
752 		seq_printf(seq, "ERROR: Unable to read battery state\n");
753 
754 	return result;
755 }
756 
757 static int acpi_battery_print_alarm(struct seq_file *seq, int result)
758 {
759 	struct acpi_battery *battery = seq->private;
760 
761 	if (result)
762 		goto end;
763 
764 	if (!acpi_battery_present(battery)) {
765 		seq_printf(seq, "present:                 no\n");
766 		goto end;
767 	}
768 	seq_printf(seq, "alarm:                   ");
769 	if (!battery->alarm)
770 		seq_printf(seq, "unsupported\n");
771 	else
772 		seq_printf(seq, "%u %sh\n", battery->alarm,
773 				acpi_battery_units(battery));
774       end:
775 	if (result)
776 		seq_printf(seq, "ERROR: Unable to read battery alarm\n");
777 	return result;
778 }
779 
780 static ssize_t acpi_battery_write_alarm(struct file *file,
781 					const char __user * buffer,
782 					size_t count, loff_t * ppos)
783 {
784 	int result = 0;
785 	char alarm_string[12] = { '\0' };
786 	struct seq_file *m = file->private_data;
787 	struct acpi_battery *battery = m->private;
788 
789 	if (!battery || (count > sizeof(alarm_string) - 1))
790 		return -EINVAL;
791 	if (!acpi_battery_present(battery)) {
792 		result = -ENODEV;
793 		goto end;
794 	}
795 	if (copy_from_user(alarm_string, buffer, count)) {
796 		result = -EFAULT;
797 		goto end;
798 	}
799 	alarm_string[count] = '\0';
800 	battery->alarm = simple_strtol(alarm_string, NULL, 0);
801 	result = acpi_battery_set_alarm(battery);
802       end:
803 	if (!result)
804 		return count;
805 	return result;
806 }
807 
808 typedef int(*print_func)(struct seq_file *seq, int result);
809 
810 static print_func acpi_print_funcs[ACPI_BATTERY_NUMFILES] = {
811 	acpi_battery_print_info,
812 	acpi_battery_print_state,
813 	acpi_battery_print_alarm,
814 };
815 
816 static int acpi_battery_read(int fid, struct seq_file *seq)
817 {
818 	struct acpi_battery *battery = seq->private;
819 	int result = acpi_battery_update(battery);
820 	return acpi_print_funcs[fid](seq, result);
821 }
822 
823 #define DECLARE_FILE_FUNCTIONS(_name) \
824 static int acpi_battery_read_##_name(struct seq_file *seq, void *offset) \
825 { \
826 	return acpi_battery_read(_name##_tag, seq); \
827 } \
828 static int acpi_battery_##_name##_open_fs(struct inode *inode, struct file *file) \
829 { \
830 	return single_open(file, acpi_battery_read_##_name, PDE(inode)->data); \
831 }
832 
833 DECLARE_FILE_FUNCTIONS(info);
834 DECLARE_FILE_FUNCTIONS(state);
835 DECLARE_FILE_FUNCTIONS(alarm);
836 
837 #undef DECLARE_FILE_FUNCTIONS
838 
839 #define FILE_DESCRIPTION_RO(_name) \
840 	{ \
841 	.name = __stringify(_name), \
842 	.mode = S_IRUGO, \
843 	.ops = { \
844 		.open = acpi_battery_##_name##_open_fs, \
845 		.read = seq_read, \
846 		.llseek = seq_lseek, \
847 		.release = single_release, \
848 		.owner = THIS_MODULE, \
849 		}, \
850 	}
851 
852 #define FILE_DESCRIPTION_RW(_name) \
853 	{ \
854 	.name = __stringify(_name), \
855 	.mode = S_IFREG | S_IRUGO | S_IWUSR, \
856 	.ops = { \
857 		.open = acpi_battery_##_name##_open_fs, \
858 		.read = seq_read, \
859 		.llseek = seq_lseek, \
860 		.write = acpi_battery_write_##_name, \
861 		.release = single_release, \
862 		.owner = THIS_MODULE, \
863 		}, \
864 	}
865 
866 static struct battery_file {
867 	struct file_operations ops;
868 	mode_t mode;
869 	const char *name;
870 } acpi_battery_file[] = {
871 	FILE_DESCRIPTION_RO(info),
872 	FILE_DESCRIPTION_RO(state),
873 	FILE_DESCRIPTION_RW(alarm),
874 };
875 
876 #undef FILE_DESCRIPTION_RO
877 #undef FILE_DESCRIPTION_RW
878 
879 static int acpi_battery_add_fs(struct acpi_device *device)
880 {
881 	struct proc_dir_entry *entry = NULL;
882 	int i;
883 
884 	printk(KERN_WARNING PREFIX "Deprecated procfs I/F for battery is loaded,"
885 			" please retry with CONFIG_ACPI_PROCFS_POWER cleared\n");
886 	if (!acpi_device_dir(device)) {
887 		acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
888 						     acpi_battery_dir);
889 		if (!acpi_device_dir(device))
890 			return -ENODEV;
891 	}
892 
893 	for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i) {
894 		entry = proc_create_data(acpi_battery_file[i].name,
895 					 acpi_battery_file[i].mode,
896 					 acpi_device_dir(device),
897 					 &acpi_battery_file[i].ops,
898 					 acpi_driver_data(device));
899 		if (!entry)
900 			return -ENODEV;
901 	}
902 	return 0;
903 }
904 
905 static void acpi_battery_remove_fs(struct acpi_device *device)
906 {
907 	int i;
908 	if (!acpi_device_dir(device))
909 		return;
910 	for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i)
911 		remove_proc_entry(acpi_battery_file[i].name,
912 				  acpi_device_dir(device));
913 
914 	remove_proc_entry(acpi_device_bid(device), acpi_battery_dir);
915 	acpi_device_dir(device) = NULL;
916 }
917 
918 #endif
919 
920 /* --------------------------------------------------------------------------
921                                  Driver Interface
922    -------------------------------------------------------------------------- */
923 
924 static void acpi_battery_notify(struct acpi_device *device, u32 event)
925 {
926 	struct acpi_battery *battery = acpi_driver_data(device);
927 	struct device *old;
928 
929 	if (!battery)
930 		return;
931 	old = battery->bat.dev;
932 	if (event == ACPI_BATTERY_NOTIFY_INFO)
933 		acpi_battery_refresh(battery);
934 	acpi_battery_update(battery);
935 	acpi_bus_generate_proc_event(device, event,
936 				     acpi_battery_present(battery));
937 	acpi_bus_generate_netlink_event(device->pnp.device_class,
938 					dev_name(&device->dev), event,
939 					acpi_battery_present(battery));
940 	/* acpi_battery_update could remove power_supply object */
941 	if (old && battery->bat.dev)
942 		power_supply_changed(&battery->bat);
943 }
944 
945 static int battery_notify(struct notifier_block *nb,
946 			       unsigned long mode, void *_unused)
947 {
948 	struct acpi_battery *battery = container_of(nb, struct acpi_battery,
949 						    pm_nb);
950 	switch (mode) {
951 	case PM_POST_SUSPEND:
952 		sysfs_remove_battery(battery);
953 		sysfs_add_battery(battery);
954 		break;
955 	}
956 
957 	return 0;
958 }
959 
960 static int acpi_battery_add(struct acpi_device *device)
961 {
962 	int result = 0;
963 	struct acpi_battery *battery = NULL;
964 	acpi_handle handle;
965 	if (!device)
966 		return -EINVAL;
967 	battery = kzalloc(sizeof(struct acpi_battery), GFP_KERNEL);
968 	if (!battery)
969 		return -ENOMEM;
970 	battery->device = device;
971 	strcpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
972 	strcpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
973 	device->driver_data = battery;
974 	mutex_init(&battery->lock);
975 	if (ACPI_SUCCESS(acpi_get_handle(battery->device->handle,
976 			"_BIX", &handle)))
977 		set_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags);
978 	acpi_battery_update(battery);
979 #ifdef CONFIG_ACPI_PROCFS_POWER
980 	result = acpi_battery_add_fs(device);
981 #endif
982 	if (!result) {
983 		printk(KERN_INFO PREFIX "%s Slot [%s] (battery %s)\n",
984 			ACPI_BATTERY_DEVICE_NAME, acpi_device_bid(device),
985 			device->status.battery_present ? "present" : "absent");
986 	} else {
987 #ifdef CONFIG_ACPI_PROCFS_POWER
988 		acpi_battery_remove_fs(device);
989 #endif
990 		kfree(battery);
991 	}
992 
993 	battery->pm_nb.notifier_call = battery_notify;
994 	register_pm_notifier(&battery->pm_nb);
995 
996 	return result;
997 }
998 
999 static int acpi_battery_remove(struct acpi_device *device, int type)
1000 {
1001 	struct acpi_battery *battery = NULL;
1002 
1003 	if (!device || !acpi_driver_data(device))
1004 		return -EINVAL;
1005 	battery = acpi_driver_data(device);
1006 	unregister_pm_notifier(&battery->pm_nb);
1007 #ifdef CONFIG_ACPI_PROCFS_POWER
1008 	acpi_battery_remove_fs(device);
1009 #endif
1010 	sysfs_remove_battery(battery);
1011 	mutex_destroy(&battery->lock);
1012 	kfree(battery);
1013 	return 0;
1014 }
1015 
1016 /* this is needed to learn about changes made in suspended state */
1017 static int acpi_battery_resume(struct acpi_device *device)
1018 {
1019 	struct acpi_battery *battery;
1020 	if (!device)
1021 		return -EINVAL;
1022 	battery = acpi_driver_data(device);
1023 	battery->update_time = 0;
1024 	acpi_battery_update(battery);
1025 	return 0;
1026 }
1027 
1028 static struct acpi_driver acpi_battery_driver = {
1029 	.name = "battery",
1030 	.class = ACPI_BATTERY_CLASS,
1031 	.ids = battery_device_ids,
1032 	.flags = ACPI_DRIVER_ALL_NOTIFY_EVENTS,
1033 	.ops = {
1034 		.add = acpi_battery_add,
1035 		.resume = acpi_battery_resume,
1036 		.remove = acpi_battery_remove,
1037 		.notify = acpi_battery_notify,
1038 		},
1039 };
1040 
1041 static void __init acpi_battery_init_async(void *unused, async_cookie_t cookie)
1042 {
1043 	if (acpi_disabled)
1044 		return;
1045 #ifdef CONFIG_ACPI_PROCFS_POWER
1046 	acpi_battery_dir = acpi_lock_battery_dir();
1047 	if (!acpi_battery_dir)
1048 		return;
1049 #endif
1050 	if (acpi_bus_register_driver(&acpi_battery_driver) < 0) {
1051 #ifdef CONFIG_ACPI_PROCFS_POWER
1052 		acpi_unlock_battery_dir(acpi_battery_dir);
1053 #endif
1054 		return;
1055 	}
1056 	return;
1057 }
1058 
1059 static int __init acpi_battery_init(void)
1060 {
1061 	async_schedule(acpi_battery_init_async, NULL);
1062 	return 0;
1063 }
1064 
1065 static void __exit acpi_battery_exit(void)
1066 {
1067 	acpi_bus_unregister_driver(&acpi_battery_driver);
1068 #ifdef CONFIG_ACPI_PROCFS_POWER
1069 	acpi_unlock_battery_dir(acpi_battery_dir);
1070 #endif
1071 }
1072 
1073 module_init(acpi_battery_init);
1074 module_exit(acpi_battery_exit);
1075