ACPI / Battery: avoid acpi_battery_add() use-after-free
[pandora-kernel.git] / drivers / acpi / battery.c
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 /* Battery power unit: 0 means mW, 1 means mA */
59 #define ACPI_BATTERY_POWER_UNIT_MA      1
60
61 #define _COMPONENT              ACPI_BATTERY_COMPONENT
62
63 ACPI_MODULE_NAME("battery");
64
65 MODULE_AUTHOR("Paul Diefenbaugh");
66 MODULE_AUTHOR("Alexey Starikovskiy <astarikovskiy@suse.de>");
67 MODULE_DESCRIPTION("ACPI Battery Driver");
68 MODULE_LICENSE("GPL");
69
70 static unsigned int cache_time = 1000;
71 module_param(cache_time, uint, 0644);
72 MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
73
74 #ifdef CONFIG_ACPI_PROCFS_POWER
75 extern struct proc_dir_entry *acpi_lock_battery_dir(void);
76 extern void *acpi_unlock_battery_dir(struct proc_dir_entry *acpi_battery_dir);
77
78 enum acpi_battery_files {
79         info_tag = 0,
80         state_tag,
81         alarm_tag,
82         ACPI_BATTERY_NUMFILES,
83 };
84
85 #endif
86
87 static const struct acpi_device_id battery_device_ids[] = {
88         {"PNP0C0A", 0},
89         {"", 0},
90 };
91
92 MODULE_DEVICE_TABLE(acpi, battery_device_ids);
93
94 enum {
95         ACPI_BATTERY_ALARM_PRESENT,
96         ACPI_BATTERY_XINFO_PRESENT,
97         ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY,
98 };
99
100 struct acpi_battery {
101         struct mutex lock;
102         struct power_supply bat;
103         struct acpi_device *device;
104         struct notifier_block pm_nb;
105         unsigned long update_time;
106         int rate_now;
107         int capacity_now;
108         int voltage_now;
109         int design_capacity;
110         int full_charge_capacity;
111         int technology;
112         int design_voltage;
113         int design_capacity_warning;
114         int design_capacity_low;
115         int cycle_count;
116         int measurement_accuracy;
117         int max_sampling_time;
118         int min_sampling_time;
119         int max_averaging_interval;
120         int min_averaging_interval;
121         int capacity_granularity_1;
122         int capacity_granularity_2;
123         int alarm;
124         char model_number[32];
125         char serial_number[32];
126         char type[32];
127         char oem_info[32];
128         int state;
129         int power_unit;
130         unsigned long flags;
131 };
132
133 #define to_acpi_battery(x) container_of(x, struct acpi_battery, bat);
134
135 inline int acpi_battery_present(struct acpi_battery *battery)
136 {
137         return battery->device->status.battery_present;
138 }
139
140 static int acpi_battery_technology(struct acpi_battery *battery)
141 {
142         if (!strcasecmp("NiCd", battery->type))
143                 return POWER_SUPPLY_TECHNOLOGY_NiCd;
144         if (!strcasecmp("NiMH", battery->type))
145                 return POWER_SUPPLY_TECHNOLOGY_NiMH;
146         if (!strcasecmp("LION", battery->type))
147                 return POWER_SUPPLY_TECHNOLOGY_LION;
148         if (!strncasecmp("LI-ION", battery->type, 6))
149                 return POWER_SUPPLY_TECHNOLOGY_LION;
150         if (!strcasecmp("LiP", battery->type))
151                 return POWER_SUPPLY_TECHNOLOGY_LIPO;
152         return POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
153 }
154
155 static int acpi_battery_get_state(struct acpi_battery *battery);
156
157 static int acpi_battery_is_charged(struct acpi_battery *battery)
158 {
159         /* either charging or discharging */
160         if (battery->state != 0)
161                 return 0;
162
163         /* battery not reporting charge */
164         if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN ||
165             battery->capacity_now == 0)
166                 return 0;
167
168         /* good batteries update full_charge as the batteries degrade */
169         if (battery->full_charge_capacity == battery->capacity_now)
170                 return 1;
171
172         /* fallback to using design values for broken batteries */
173         if (battery->design_capacity == battery->capacity_now)
174                 return 1;
175
176         /* we don't do any sort of metric based on percentages */
177         return 0;
178 }
179
180 static int acpi_battery_get_property(struct power_supply *psy,
181                                      enum power_supply_property psp,
182                                      union power_supply_propval *val)
183 {
184         int ret = 0;
185         struct acpi_battery *battery = to_acpi_battery(psy);
186
187         if (acpi_battery_present(battery)) {
188                 /* run battery update only if it is present */
189                 acpi_battery_get_state(battery);
190         } else if (psp != POWER_SUPPLY_PROP_PRESENT)
191                 return -ENODEV;
192         switch (psp) {
193         case POWER_SUPPLY_PROP_STATUS:
194                 if (battery->state & 0x01)
195                         val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
196                 else if (battery->state & 0x02)
197                         val->intval = POWER_SUPPLY_STATUS_CHARGING;
198                 else if (acpi_battery_is_charged(battery))
199                         val->intval = POWER_SUPPLY_STATUS_FULL;
200                 else
201                         val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
202                 break;
203         case POWER_SUPPLY_PROP_PRESENT:
204                 val->intval = acpi_battery_present(battery);
205                 break;
206         case POWER_SUPPLY_PROP_TECHNOLOGY:
207                 val->intval = acpi_battery_technology(battery);
208                 break;
209         case POWER_SUPPLY_PROP_CYCLE_COUNT:
210                 val->intval = battery->cycle_count;
211                 break;
212         case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
213                 if (battery->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
214                         ret = -ENODEV;
215                 else
216                         val->intval = battery->design_voltage * 1000;
217                 break;
218         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
219                 if (battery->voltage_now == ACPI_BATTERY_VALUE_UNKNOWN)
220                         ret = -ENODEV;
221                 else
222                         val->intval = battery->voltage_now * 1000;
223                 break;
224         case POWER_SUPPLY_PROP_CURRENT_NOW:
225         case POWER_SUPPLY_PROP_POWER_NOW:
226                 if (battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN)
227                         ret = -ENODEV;
228                 else
229                         val->intval = battery->rate_now * 1000;
230                 break;
231         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
232         case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
233                 if (battery->design_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
234                         ret = -ENODEV;
235                 else
236                         val->intval = battery->design_capacity * 1000;
237                 break;
238         case POWER_SUPPLY_PROP_CHARGE_FULL:
239         case POWER_SUPPLY_PROP_ENERGY_FULL:
240                 if (battery->full_charge_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
241                         ret = -ENODEV;
242                 else
243                         val->intval = battery->full_charge_capacity * 1000;
244                 break;
245         case POWER_SUPPLY_PROP_CHARGE_NOW:
246         case POWER_SUPPLY_PROP_ENERGY_NOW:
247                 if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN)
248                         ret = -ENODEV;
249                 else
250                         val->intval = battery->capacity_now * 1000;
251                 break;
252         case POWER_SUPPLY_PROP_MODEL_NAME:
253                 val->strval = battery->model_number;
254                 break;
255         case POWER_SUPPLY_PROP_MANUFACTURER:
256                 val->strval = battery->oem_info;
257                 break;
258         case POWER_SUPPLY_PROP_SERIAL_NUMBER:
259                 val->strval = battery->serial_number;
260                 break;
261         default:
262                 ret = -EINVAL;
263         }
264         return ret;
265 }
266
267 static enum power_supply_property charge_battery_props[] = {
268         POWER_SUPPLY_PROP_STATUS,
269         POWER_SUPPLY_PROP_PRESENT,
270         POWER_SUPPLY_PROP_TECHNOLOGY,
271         POWER_SUPPLY_PROP_CYCLE_COUNT,
272         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
273         POWER_SUPPLY_PROP_VOLTAGE_NOW,
274         POWER_SUPPLY_PROP_CURRENT_NOW,
275         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
276         POWER_SUPPLY_PROP_CHARGE_FULL,
277         POWER_SUPPLY_PROP_CHARGE_NOW,
278         POWER_SUPPLY_PROP_MODEL_NAME,
279         POWER_SUPPLY_PROP_MANUFACTURER,
280         POWER_SUPPLY_PROP_SERIAL_NUMBER,
281 };
282
283 static enum power_supply_property energy_battery_props[] = {
284         POWER_SUPPLY_PROP_STATUS,
285         POWER_SUPPLY_PROP_PRESENT,
286         POWER_SUPPLY_PROP_TECHNOLOGY,
287         POWER_SUPPLY_PROP_CYCLE_COUNT,
288         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
289         POWER_SUPPLY_PROP_VOLTAGE_NOW,
290         POWER_SUPPLY_PROP_POWER_NOW,
291         POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
292         POWER_SUPPLY_PROP_ENERGY_FULL,
293         POWER_SUPPLY_PROP_ENERGY_NOW,
294         POWER_SUPPLY_PROP_MODEL_NAME,
295         POWER_SUPPLY_PROP_MANUFACTURER,
296         POWER_SUPPLY_PROP_SERIAL_NUMBER,
297 };
298
299 #ifdef CONFIG_ACPI_PROCFS_POWER
300 inline char *acpi_battery_units(struct acpi_battery *battery)
301 {
302         return (battery->power_unit == ACPI_BATTERY_POWER_UNIT_MA) ?
303                 "mA" : "mW";
304 }
305 #endif
306
307 /* --------------------------------------------------------------------------
308                                Battery Management
309    -------------------------------------------------------------------------- */
310 struct acpi_offsets {
311         size_t offset;          /* offset inside struct acpi_sbs_battery */
312         u8 mode;                /* int or string? */
313 };
314
315 static struct acpi_offsets state_offsets[] = {
316         {offsetof(struct acpi_battery, state), 0},
317         {offsetof(struct acpi_battery, rate_now), 0},
318         {offsetof(struct acpi_battery, capacity_now), 0},
319         {offsetof(struct acpi_battery, voltage_now), 0},
320 };
321
322 static struct acpi_offsets info_offsets[] = {
323         {offsetof(struct acpi_battery, power_unit), 0},
324         {offsetof(struct acpi_battery, design_capacity), 0},
325         {offsetof(struct acpi_battery, full_charge_capacity), 0},
326         {offsetof(struct acpi_battery, technology), 0},
327         {offsetof(struct acpi_battery, design_voltage), 0},
328         {offsetof(struct acpi_battery, design_capacity_warning), 0},
329         {offsetof(struct acpi_battery, design_capacity_low), 0},
330         {offsetof(struct acpi_battery, capacity_granularity_1), 0},
331         {offsetof(struct acpi_battery, capacity_granularity_2), 0},
332         {offsetof(struct acpi_battery, model_number), 1},
333         {offsetof(struct acpi_battery, serial_number), 1},
334         {offsetof(struct acpi_battery, type), 1},
335         {offsetof(struct acpi_battery, oem_info), 1},
336 };
337
338 static struct acpi_offsets extended_info_offsets[] = {
339         {offsetof(struct acpi_battery, power_unit), 0},
340         {offsetof(struct acpi_battery, design_capacity), 0},
341         {offsetof(struct acpi_battery, full_charge_capacity), 0},
342         {offsetof(struct acpi_battery, technology), 0},
343         {offsetof(struct acpi_battery, design_voltage), 0},
344         {offsetof(struct acpi_battery, design_capacity_warning), 0},
345         {offsetof(struct acpi_battery, design_capacity_low), 0},
346         {offsetof(struct acpi_battery, cycle_count), 0},
347         {offsetof(struct acpi_battery, measurement_accuracy), 0},
348         {offsetof(struct acpi_battery, max_sampling_time), 0},
349         {offsetof(struct acpi_battery, min_sampling_time), 0},
350         {offsetof(struct acpi_battery, max_averaging_interval), 0},
351         {offsetof(struct acpi_battery, min_averaging_interval), 0},
352         {offsetof(struct acpi_battery, capacity_granularity_1), 0},
353         {offsetof(struct acpi_battery, capacity_granularity_2), 0},
354         {offsetof(struct acpi_battery, model_number), 1},
355         {offsetof(struct acpi_battery, serial_number), 1},
356         {offsetof(struct acpi_battery, type), 1},
357         {offsetof(struct acpi_battery, oem_info), 1},
358 };
359
360 static int extract_package(struct acpi_battery *battery,
361                            union acpi_object *package,
362                            struct acpi_offsets *offsets, int num)
363 {
364         int i;
365         union acpi_object *element;
366         if (package->type != ACPI_TYPE_PACKAGE)
367                 return -EFAULT;
368         for (i = 0; i < num; ++i) {
369                 if (package->package.count <= i)
370                         return -EFAULT;
371                 element = &package->package.elements[i];
372                 if (offsets[i].mode) {
373                         u8 *ptr = (u8 *)battery + offsets[i].offset;
374                         if (element->type == ACPI_TYPE_STRING ||
375                             element->type == ACPI_TYPE_BUFFER)
376                                 strncpy(ptr, element->string.pointer, 32);
377                         else if (element->type == ACPI_TYPE_INTEGER) {
378                                 strncpy(ptr, (u8 *)&element->integer.value,
379                                         sizeof(u64));
380                                 ptr[sizeof(u64)] = 0;
381                         } else
382                                 *ptr = 0; /* don't have value */
383                 } else {
384                         int *x = (int *)((u8 *)battery + offsets[i].offset);
385                         *x = (element->type == ACPI_TYPE_INTEGER) ?
386                                 element->integer.value : -1;
387                 }
388         }
389         return 0;
390 }
391
392 static int acpi_battery_get_status(struct acpi_battery *battery)
393 {
394         if (acpi_bus_get_status(battery->device)) {
395                 ACPI_EXCEPTION((AE_INFO, AE_ERROR, "Evaluating _STA"));
396                 return -ENODEV;
397         }
398         return 0;
399 }
400
401 static int acpi_battery_get_info(struct acpi_battery *battery)
402 {
403         int result = -EFAULT;
404         acpi_status status = 0;
405         char *name = test_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags)?
406                         "_BIX" : "_BIF";
407
408         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
409
410         if (!acpi_battery_present(battery))
411                 return 0;
412         mutex_lock(&battery->lock);
413         status = acpi_evaluate_object(battery->device->handle, name,
414                                                 NULL, &buffer);
415         mutex_unlock(&battery->lock);
416
417         if (ACPI_FAILURE(status)) {
418                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating %s", name));
419                 return -ENODEV;
420         }
421         if (test_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags))
422                 result = extract_package(battery, buffer.pointer,
423                                 extended_info_offsets,
424                                 ARRAY_SIZE(extended_info_offsets));
425         else
426                 result = extract_package(battery, buffer.pointer,
427                                 info_offsets, ARRAY_SIZE(info_offsets));
428         kfree(buffer.pointer);
429         if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags))
430                 battery->full_charge_capacity = battery->design_capacity;
431         return result;
432 }
433
434 static int acpi_battery_get_state(struct acpi_battery *battery)
435 {
436         int result = 0;
437         acpi_status status = 0;
438         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
439
440         if (!acpi_battery_present(battery))
441                 return 0;
442
443         if (battery->update_time &&
444             time_before(jiffies, battery->update_time +
445                         msecs_to_jiffies(cache_time)))
446                 return 0;
447
448         mutex_lock(&battery->lock);
449         status = acpi_evaluate_object(battery->device->handle, "_BST",
450                                       NULL, &buffer);
451         mutex_unlock(&battery->lock);
452
453         if (ACPI_FAILURE(status)) {
454                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BST"));
455                 return -ENODEV;
456         }
457
458         result = extract_package(battery, buffer.pointer,
459                                  state_offsets, ARRAY_SIZE(state_offsets));
460         battery->update_time = jiffies;
461         kfree(buffer.pointer);
462
463         /* For buggy DSDTs that report negative 16-bit values for either
464          * charging or discharging current and/or report 0 as 65536
465          * due to bad math.
466          */
467         if (battery->power_unit == ACPI_BATTERY_POWER_UNIT_MA &&
468                 battery->rate_now != ACPI_BATTERY_VALUE_UNKNOWN &&
469                 (s16)(battery->rate_now) < 0) {
470                 battery->rate_now = abs((s16)battery->rate_now);
471                 printk_once(KERN_WARNING FW_BUG "battery: (dis)charge rate"
472                         " invalid.\n");
473         }
474
475         if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags)
476             && battery->capacity_now >= 0 && battery->capacity_now <= 100)
477                 battery->capacity_now = (battery->capacity_now *
478                                 battery->full_charge_capacity) / 100;
479         return result;
480 }
481
482 static int acpi_battery_set_alarm(struct acpi_battery *battery)
483 {
484         acpi_status status = 0;
485         union acpi_object arg0 = { .type = ACPI_TYPE_INTEGER };
486         struct acpi_object_list arg_list = { 1, &arg0 };
487
488         if (!acpi_battery_present(battery) ||
489             !test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags))
490                 return -ENODEV;
491
492         arg0.integer.value = battery->alarm;
493
494         mutex_lock(&battery->lock);
495         status = acpi_evaluate_object(battery->device->handle, "_BTP",
496                                  &arg_list, NULL);
497         mutex_unlock(&battery->lock);
498
499         if (ACPI_FAILURE(status))
500                 return -ENODEV;
501
502         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Alarm set to %d\n", battery->alarm));
503         return 0;
504 }
505
506 static int acpi_battery_init_alarm(struct acpi_battery *battery)
507 {
508         acpi_status status = AE_OK;
509         acpi_handle handle = NULL;
510
511         /* See if alarms are supported, and if so, set default */
512         status = acpi_get_handle(battery->device->handle, "_BTP", &handle);
513         if (ACPI_FAILURE(status)) {
514                 clear_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags);
515                 return 0;
516         }
517         set_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags);
518         if (!battery->alarm)
519                 battery->alarm = battery->design_capacity_warning;
520         return acpi_battery_set_alarm(battery);
521 }
522
523 static ssize_t acpi_battery_alarm_show(struct device *dev,
524                                         struct device_attribute *attr,
525                                         char *buf)
526 {
527         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
528         return sprintf(buf, "%d\n", battery->alarm * 1000);
529 }
530
531 static ssize_t acpi_battery_alarm_store(struct device *dev,
532                                         struct device_attribute *attr,
533                                         const char *buf, size_t count)
534 {
535         unsigned long x;
536         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
537         if (sscanf(buf, "%ld\n", &x) == 1)
538                 battery->alarm = x/1000;
539         if (acpi_battery_present(battery))
540                 acpi_battery_set_alarm(battery);
541         return count;
542 }
543
544 static struct device_attribute alarm_attr = {
545         .attr = {.name = "alarm", .mode = 0644},
546         .show = acpi_battery_alarm_show,
547         .store = acpi_battery_alarm_store,
548 };
549
550 static int sysfs_add_battery(struct acpi_battery *battery)
551 {
552         int result;
553
554         if (battery->power_unit == ACPI_BATTERY_POWER_UNIT_MA) {
555                 battery->bat.properties = charge_battery_props;
556                 battery->bat.num_properties =
557                         ARRAY_SIZE(charge_battery_props);
558         } else {
559                 battery->bat.properties = energy_battery_props;
560                 battery->bat.num_properties =
561                         ARRAY_SIZE(energy_battery_props);
562         }
563
564         battery->bat.name = acpi_device_bid(battery->device);
565         battery->bat.type = POWER_SUPPLY_TYPE_BATTERY;
566         battery->bat.get_property = acpi_battery_get_property;
567
568         result = power_supply_register(&battery->device->dev, &battery->bat);
569         if (result)
570                 return result;
571         return device_create_file(battery->bat.dev, &alarm_attr);
572 }
573
574 static void sysfs_remove_battery(struct acpi_battery *battery)
575 {
576         mutex_lock(&battery->lock);
577         if (!battery->bat.dev) {
578                 mutex_unlock(&battery->lock);
579                 return;
580         }
581
582         device_remove_file(battery->bat.dev, &alarm_attr);
583         power_supply_unregister(&battery->bat);
584         battery->bat.dev = NULL;
585         mutex_unlock(&battery->lock);
586 }
587
588 /*
589  * According to the ACPI spec, some kinds of primary batteries can
590  * report percentage battery remaining capacity directly to OS.
591  * In this case, it reports the Last Full Charged Capacity == 100
592  * and BatteryPresentRate == 0xFFFFFFFF.
593  *
594  * Now we found some battery reports percentage remaining capacity
595  * even if it's rechargeable.
596  * https://bugzilla.kernel.org/show_bug.cgi?id=15979
597  *
598  * Handle this correctly so that they won't break userspace.
599  */
600 static void acpi_battery_quirks(struct acpi_battery *battery)
601 {
602         if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags))
603                 return ;
604
605         if (battery->full_charge_capacity == 100 &&
606             battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN &&
607             battery->capacity_now >=0 && battery->capacity_now <= 100) {
608                 set_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags);
609                 battery->full_charge_capacity = battery->design_capacity;
610                 battery->capacity_now = (battery->capacity_now *
611                                 battery->full_charge_capacity) / 100;
612         }
613 }
614
615 static int acpi_battery_update(struct acpi_battery *battery)
616 {
617         int result, old_present = acpi_battery_present(battery);
618         result = acpi_battery_get_status(battery);
619         if (result)
620                 return result;
621         if (!acpi_battery_present(battery)) {
622                 sysfs_remove_battery(battery);
623                 battery->update_time = 0;
624                 return 0;
625         }
626         if (!battery->update_time ||
627             old_present != acpi_battery_present(battery)) {
628                 result = acpi_battery_get_info(battery);
629                 if (result)
630                         return result;
631                 acpi_battery_init_alarm(battery);
632         }
633         if (!battery->bat.dev)
634                 sysfs_add_battery(battery);
635         result = acpi_battery_get_state(battery);
636         acpi_battery_quirks(battery);
637         return result;
638 }
639
640 static void acpi_battery_refresh(struct acpi_battery *battery)
641 {
642         if (!battery->bat.dev)
643                 return;
644
645         acpi_battery_get_info(battery);
646         /* The battery may have changed its reporting units. */
647         sysfs_remove_battery(battery);
648         sysfs_add_battery(battery);
649 }
650
651 /* --------------------------------------------------------------------------
652                               FS Interface (/proc)
653    -------------------------------------------------------------------------- */
654
655 #ifdef CONFIG_ACPI_PROCFS_POWER
656 static struct proc_dir_entry *acpi_battery_dir;
657
658 static int acpi_battery_print_info(struct seq_file *seq, int result)
659 {
660         struct acpi_battery *battery = seq->private;
661
662         if (result)
663                 goto end;
664
665         seq_printf(seq, "present:                 %s\n",
666                    acpi_battery_present(battery)?"yes":"no");
667         if (!acpi_battery_present(battery))
668                 goto end;
669         if (battery->design_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
670                 seq_printf(seq, "design capacity:         unknown\n");
671         else
672                 seq_printf(seq, "design capacity:         %d %sh\n",
673                            battery->design_capacity,
674                            acpi_battery_units(battery));
675
676         if (battery->full_charge_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
677                 seq_printf(seq, "last full capacity:      unknown\n");
678         else
679                 seq_printf(seq, "last full capacity:      %d %sh\n",
680                            battery->full_charge_capacity,
681                            acpi_battery_units(battery));
682
683         seq_printf(seq, "battery technology:      %srechargeable\n",
684                    (!battery->technology)?"non-":"");
685
686         if (battery->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
687                 seq_printf(seq, "design voltage:          unknown\n");
688         else
689                 seq_printf(seq, "design voltage:          %d mV\n",
690                            battery->design_voltage);
691         seq_printf(seq, "design capacity warning: %d %sh\n",
692                    battery->design_capacity_warning,
693                    acpi_battery_units(battery));
694         seq_printf(seq, "design capacity low:     %d %sh\n",
695                    battery->design_capacity_low,
696                    acpi_battery_units(battery));
697         seq_printf(seq, "cycle count:             %i\n", battery->cycle_count);
698         seq_printf(seq, "capacity granularity 1:  %d %sh\n",
699                    battery->capacity_granularity_1,
700                    acpi_battery_units(battery));
701         seq_printf(seq, "capacity granularity 2:  %d %sh\n",
702                    battery->capacity_granularity_2,
703                    acpi_battery_units(battery));
704         seq_printf(seq, "model number:            %s\n", battery->model_number);
705         seq_printf(seq, "serial number:           %s\n", battery->serial_number);
706         seq_printf(seq, "battery type:            %s\n", battery->type);
707         seq_printf(seq, "OEM info:                %s\n", battery->oem_info);
708       end:
709         if (result)
710                 seq_printf(seq, "ERROR: Unable to read battery info\n");
711         return result;
712 }
713
714 static int acpi_battery_print_state(struct seq_file *seq, int result)
715 {
716         struct acpi_battery *battery = seq->private;
717
718         if (result)
719                 goto end;
720
721         seq_printf(seq, "present:                 %s\n",
722                    acpi_battery_present(battery)?"yes":"no");
723         if (!acpi_battery_present(battery))
724                 goto end;
725
726         seq_printf(seq, "capacity state:          %s\n",
727                         (battery->state & 0x04)?"critical":"ok");
728         if ((battery->state & 0x01) && (battery->state & 0x02))
729                 seq_printf(seq,
730                            "charging state:          charging/discharging\n");
731         else if (battery->state & 0x01)
732                 seq_printf(seq, "charging state:          discharging\n");
733         else if (battery->state & 0x02)
734                 seq_printf(seq, "charging state:          charging\n");
735         else
736                 seq_printf(seq, "charging state:          charged\n");
737
738         if (battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN)
739                 seq_printf(seq, "present rate:            unknown\n");
740         else
741                 seq_printf(seq, "present rate:            %d %s\n",
742                            battery->rate_now, acpi_battery_units(battery));
743
744         if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN)
745                 seq_printf(seq, "remaining capacity:      unknown\n");
746         else
747                 seq_printf(seq, "remaining capacity:      %d %sh\n",
748                            battery->capacity_now, acpi_battery_units(battery));
749         if (battery->voltage_now == ACPI_BATTERY_VALUE_UNKNOWN)
750                 seq_printf(seq, "present voltage:         unknown\n");
751         else
752                 seq_printf(seq, "present voltage:         %d mV\n",
753                            battery->voltage_now);
754       end:
755         if (result)
756                 seq_printf(seq, "ERROR: Unable to read battery state\n");
757
758         return result;
759 }
760
761 static int acpi_battery_print_alarm(struct seq_file *seq, int result)
762 {
763         struct acpi_battery *battery = seq->private;
764
765         if (result)
766                 goto end;
767
768         if (!acpi_battery_present(battery)) {
769                 seq_printf(seq, "present:                 no\n");
770                 goto end;
771         }
772         seq_printf(seq, "alarm:                   ");
773         if (!battery->alarm)
774                 seq_printf(seq, "unsupported\n");
775         else
776                 seq_printf(seq, "%u %sh\n", battery->alarm,
777                                 acpi_battery_units(battery));
778       end:
779         if (result)
780                 seq_printf(seq, "ERROR: Unable to read battery alarm\n");
781         return result;
782 }
783
784 static ssize_t acpi_battery_write_alarm(struct file *file,
785                                         const char __user * buffer,
786                                         size_t count, loff_t * ppos)
787 {
788         int result = 0;
789         char alarm_string[12] = { '\0' };
790         struct seq_file *m = file->private_data;
791         struct acpi_battery *battery = m->private;
792
793         if (!battery || (count > sizeof(alarm_string) - 1))
794                 return -EINVAL;
795         if (!acpi_battery_present(battery)) {
796                 result = -ENODEV;
797                 goto end;
798         }
799         if (copy_from_user(alarm_string, buffer, count)) {
800                 result = -EFAULT;
801                 goto end;
802         }
803         alarm_string[count] = '\0';
804         battery->alarm = simple_strtol(alarm_string, NULL, 0);
805         result = acpi_battery_set_alarm(battery);
806       end:
807         if (!result)
808                 return count;
809         return result;
810 }
811
812 typedef int(*print_func)(struct seq_file *seq, int result);
813
814 static print_func acpi_print_funcs[ACPI_BATTERY_NUMFILES] = {
815         acpi_battery_print_info,
816         acpi_battery_print_state,
817         acpi_battery_print_alarm,
818 };
819
820 static int acpi_battery_read(int fid, struct seq_file *seq)
821 {
822         struct acpi_battery *battery = seq->private;
823         int result = acpi_battery_update(battery);
824         return acpi_print_funcs[fid](seq, result);
825 }
826
827 #define DECLARE_FILE_FUNCTIONS(_name) \
828 static int acpi_battery_read_##_name(struct seq_file *seq, void *offset) \
829 { \
830         return acpi_battery_read(_name##_tag, seq); \
831 } \
832 static int acpi_battery_##_name##_open_fs(struct inode *inode, struct file *file) \
833 { \
834         return single_open(file, acpi_battery_read_##_name, PDE(inode)->data); \
835 }
836
837 DECLARE_FILE_FUNCTIONS(info);
838 DECLARE_FILE_FUNCTIONS(state);
839 DECLARE_FILE_FUNCTIONS(alarm);
840
841 #undef DECLARE_FILE_FUNCTIONS
842
843 #define FILE_DESCRIPTION_RO(_name) \
844         { \
845         .name = __stringify(_name), \
846         .mode = S_IRUGO, \
847         .ops = { \
848                 .open = acpi_battery_##_name##_open_fs, \
849                 .read = seq_read, \
850                 .llseek = seq_lseek, \
851                 .release = single_release, \
852                 .owner = THIS_MODULE, \
853                 }, \
854         }
855
856 #define FILE_DESCRIPTION_RW(_name) \
857         { \
858         .name = __stringify(_name), \
859         .mode = S_IFREG | S_IRUGO | S_IWUSR, \
860         .ops = { \
861                 .open = acpi_battery_##_name##_open_fs, \
862                 .read = seq_read, \
863                 .llseek = seq_lseek, \
864                 .write = acpi_battery_write_##_name, \
865                 .release = single_release, \
866                 .owner = THIS_MODULE, \
867                 }, \
868         }
869
870 static struct battery_file {
871         struct file_operations ops;
872         mode_t mode;
873         const char *name;
874 } acpi_battery_file[] = {
875         FILE_DESCRIPTION_RO(info),
876         FILE_DESCRIPTION_RO(state),
877         FILE_DESCRIPTION_RW(alarm),
878 };
879
880 #undef FILE_DESCRIPTION_RO
881 #undef FILE_DESCRIPTION_RW
882
883 static int acpi_battery_add_fs(struct acpi_device *device)
884 {
885         struct proc_dir_entry *entry = NULL;
886         int i;
887
888         printk(KERN_WARNING PREFIX "Deprecated procfs I/F for battery is loaded,"
889                         " please retry with CONFIG_ACPI_PROCFS_POWER cleared\n");
890         if (!acpi_device_dir(device)) {
891                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
892                                                      acpi_battery_dir);
893                 if (!acpi_device_dir(device))
894                         return -ENODEV;
895         }
896
897         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i) {
898                 entry = proc_create_data(acpi_battery_file[i].name,
899                                          acpi_battery_file[i].mode,
900                                          acpi_device_dir(device),
901                                          &acpi_battery_file[i].ops,
902                                          acpi_driver_data(device));
903                 if (!entry)
904                         return -ENODEV;
905         }
906         return 0;
907 }
908
909 static void acpi_battery_remove_fs(struct acpi_device *device)
910 {
911         int i;
912         if (!acpi_device_dir(device))
913                 return;
914         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i)
915                 remove_proc_entry(acpi_battery_file[i].name,
916                                   acpi_device_dir(device));
917
918         remove_proc_entry(acpi_device_bid(device), acpi_battery_dir);
919         acpi_device_dir(device) = NULL;
920 }
921
922 #endif
923
924 /* --------------------------------------------------------------------------
925                                  Driver Interface
926    -------------------------------------------------------------------------- */
927
928 static void acpi_battery_notify(struct acpi_device *device, u32 event)
929 {
930         struct acpi_battery *battery = acpi_driver_data(device);
931         struct device *old;
932
933         if (!battery)
934                 return;
935         old = battery->bat.dev;
936         if (event == ACPI_BATTERY_NOTIFY_INFO)
937                 acpi_battery_refresh(battery);
938         acpi_battery_update(battery);
939         acpi_bus_generate_proc_event(device, event,
940                                      acpi_battery_present(battery));
941         acpi_bus_generate_netlink_event(device->pnp.device_class,
942                                         dev_name(&device->dev), event,
943                                         acpi_battery_present(battery));
944         /* acpi_battery_update could remove power_supply object */
945         if (old && battery->bat.dev)
946                 power_supply_changed(&battery->bat);
947 }
948
949 static int battery_notify(struct notifier_block *nb,
950                                unsigned long mode, void *_unused)
951 {
952         struct acpi_battery *battery = container_of(nb, struct acpi_battery,
953                                                     pm_nb);
954         switch (mode) {
955         case PM_POST_HIBERNATION:
956         case PM_POST_SUSPEND:
957                 if (battery->bat.dev) {
958                         sysfs_remove_battery(battery);
959                         sysfs_add_battery(battery);
960                 }
961                 break;
962         }
963
964         return 0;
965 }
966
967 static int acpi_battery_add(struct acpi_device *device)
968 {
969         int result = 0;
970         struct acpi_battery *battery = NULL;
971         acpi_handle handle;
972         if (!device)
973                 return -EINVAL;
974         battery = kzalloc(sizeof(struct acpi_battery), GFP_KERNEL);
975         if (!battery)
976                 return -ENOMEM;
977         battery->device = device;
978         strcpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
979         strcpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
980         device->driver_data = battery;
981         mutex_init(&battery->lock);
982         if (ACPI_SUCCESS(acpi_get_handle(battery->device->handle,
983                         "_BIX", &handle)))
984                 set_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags);
985         acpi_battery_update(battery);
986 #ifdef CONFIG_ACPI_PROCFS_POWER
987         result = acpi_battery_add_fs(device);
988 #endif
989         if (result) {
990 #ifdef CONFIG_ACPI_PROCFS_POWER
991                 acpi_battery_remove_fs(device);
992 #endif
993                 goto fail;
994         }
995
996         printk(KERN_INFO PREFIX "%s Slot [%s] (battery %s)\n",
997                 ACPI_BATTERY_DEVICE_NAME, acpi_device_bid(device),
998                 device->status.battery_present ? "present" : "absent");
999
1000         battery->pm_nb.notifier_call = battery_notify;
1001         register_pm_notifier(&battery->pm_nb);
1002
1003         return result;
1004
1005 fail:
1006         sysfs_remove_battery(battery);
1007         mutex_destroy(&battery->lock);
1008         kfree(battery);
1009         return result;
1010 }
1011
1012 static int acpi_battery_remove(struct acpi_device *device, int type)
1013 {
1014         struct acpi_battery *battery = NULL;
1015
1016         if (!device || !acpi_driver_data(device))
1017                 return -EINVAL;
1018         battery = acpi_driver_data(device);
1019         unregister_pm_notifier(&battery->pm_nb);
1020 #ifdef CONFIG_ACPI_PROCFS_POWER
1021         acpi_battery_remove_fs(device);
1022 #endif
1023         sysfs_remove_battery(battery);
1024         mutex_destroy(&battery->lock);
1025         kfree(battery);
1026         return 0;
1027 }
1028
1029 /* this is needed to learn about changes made in suspended state */
1030 static int acpi_battery_resume(struct acpi_device *device)
1031 {
1032         struct acpi_battery *battery;
1033         if (!device)
1034                 return -EINVAL;
1035         battery = acpi_driver_data(device);
1036         battery->update_time = 0;
1037         acpi_battery_update(battery);
1038         return 0;
1039 }
1040
1041 static struct acpi_driver acpi_battery_driver = {
1042         .name = "battery",
1043         .class = ACPI_BATTERY_CLASS,
1044         .ids = battery_device_ids,
1045         .flags = ACPI_DRIVER_ALL_NOTIFY_EVENTS,
1046         .ops = {
1047                 .add = acpi_battery_add,
1048                 .resume = acpi_battery_resume,
1049                 .remove = acpi_battery_remove,
1050                 .notify = acpi_battery_notify,
1051                 },
1052 };
1053
1054 static void __init acpi_battery_init_async(void *unused, async_cookie_t cookie)
1055 {
1056         if (acpi_disabled)
1057                 return;
1058 #ifdef CONFIG_ACPI_PROCFS_POWER
1059         acpi_battery_dir = acpi_lock_battery_dir();
1060         if (!acpi_battery_dir)
1061                 return;
1062 #endif
1063         if (acpi_bus_register_driver(&acpi_battery_driver) < 0) {
1064 #ifdef CONFIG_ACPI_PROCFS_POWER
1065                 acpi_unlock_battery_dir(acpi_battery_dir);
1066 #endif
1067                 return;
1068         }
1069         return;
1070 }
1071
1072 static int __init acpi_battery_init(void)
1073 {
1074         async_schedule(acpi_battery_init_async, NULL);
1075         return 0;
1076 }
1077
1078 static void __exit acpi_battery_exit(void)
1079 {
1080         acpi_bus_unregister_driver(&acpi_battery_driver);
1081 #ifdef CONFIG_ACPI_PROCFS_POWER
1082         acpi_unlock_battery_dir(acpi_battery_dir);
1083 #endif
1084 }
1085
1086 module_init(acpi_battery_init);
1087 module_exit(acpi_battery_exit);