Merge branch 'battery' into release
[sfrench/cifs-2.6.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
36 #ifdef CONFIG_ACPI_PROCFS_POWER
37 #include <linux/proc_fs.h>
38 #include <linux/seq_file.h>
39 #include <asm/uaccess.h>
40 #endif
41
42 #include <acpi/acpi_bus.h>
43 #include <acpi/acpi_drivers.h>
44
45 #ifdef CONFIG_ACPI_SYSFS_POWER
46 #include <linux/power_supply.h>
47 #endif
48
49 #define PREFIX "ACPI: "
50
51 #define ACPI_BATTERY_VALUE_UNKNOWN 0xFFFFFFFF
52
53 #define ACPI_BATTERY_CLASS              "battery"
54 #define ACPI_BATTERY_DEVICE_NAME        "Battery"
55 #define ACPI_BATTERY_NOTIFY_STATUS      0x80
56 #define ACPI_BATTERY_NOTIFY_INFO        0x81
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 /* For buggy DSDTs that report negative 16-bit values for either charging
92  * or discharging current and/or report 0 as 65536 due to bad math.
93  */
94 #define QUIRK_SIGNED16_CURRENT 0x0001
95
96 struct acpi_battery {
97         struct mutex lock;
98 #ifdef CONFIG_ACPI_SYSFS_POWER
99         struct power_supply bat;
100 #endif
101         struct acpi_device *device;
102         unsigned long update_time;
103         int rate_now;
104         int capacity_now;
105         int voltage_now;
106         int design_capacity;
107         int full_charge_capacity;
108         int technology;
109         int design_voltage;
110         int design_capacity_warning;
111         int design_capacity_low;
112         int capacity_granularity_1;
113         int capacity_granularity_2;
114         int alarm;
115         char model_number[32];
116         char serial_number[32];
117         char type[32];
118         char oem_info[32];
119         int state;
120         int power_unit;
121         u8 alarm_present;
122         long quirks;
123 };
124
125 #define to_acpi_battery(x) container_of(x, struct acpi_battery, bat);
126
127 inline int acpi_battery_present(struct acpi_battery *battery)
128 {
129         return battery->device->status.battery_present;
130 }
131
132 #ifdef CONFIG_ACPI_SYSFS_POWER
133 static int acpi_battery_technology(struct acpi_battery *battery)
134 {
135         if (!strcasecmp("NiCd", battery->type))
136                 return POWER_SUPPLY_TECHNOLOGY_NiCd;
137         if (!strcasecmp("NiMH", battery->type))
138                 return POWER_SUPPLY_TECHNOLOGY_NiMH;
139         if (!strcasecmp("LION", battery->type))
140                 return POWER_SUPPLY_TECHNOLOGY_LION;
141         if (!strncasecmp("LI-ION", battery->type, 6))
142                 return POWER_SUPPLY_TECHNOLOGY_LION;
143         if (!strcasecmp("LiP", battery->type))
144                 return POWER_SUPPLY_TECHNOLOGY_LIPO;
145         return POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
146 }
147
148 static int acpi_battery_get_state(struct acpi_battery *battery);
149
150 static int acpi_battery_is_charged(struct acpi_battery *battery)
151 {
152         /* either charging or discharging */
153         if (battery->state != 0)
154                 return 0;
155
156         /* battery not reporting charge */
157         if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN ||
158             battery->capacity_now == 0)
159                 return 0;
160
161         /* good batteries update full_charge as the batteries degrade */
162         if (battery->full_charge_capacity == battery->capacity_now)
163                 return 1;
164
165         /* fallback to using design values for broken batteries */
166         if (battery->design_capacity == battery->capacity_now)
167                 return 1;
168
169         /* we don't do any sort of metric based on percentages */
170         return 0;
171 }
172
173 static int acpi_battery_get_property(struct power_supply *psy,
174                                      enum power_supply_property psp,
175                                      union power_supply_propval *val)
176 {
177         struct acpi_battery *battery = to_acpi_battery(psy);
178
179         if (acpi_battery_present(battery)) {
180                 /* run battery update only if it is present */
181                 acpi_battery_get_state(battery);
182         } else if (psp != POWER_SUPPLY_PROP_PRESENT)
183                 return -ENODEV;
184         switch (psp) {
185         case POWER_SUPPLY_PROP_STATUS:
186                 if (battery->state & 0x01)
187                         val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
188                 else if (battery->state & 0x02)
189                         val->intval = POWER_SUPPLY_STATUS_CHARGING;
190                 else if (acpi_battery_is_charged(battery))
191                         val->intval = POWER_SUPPLY_STATUS_FULL;
192                 else
193                         val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
194                 break;
195         case POWER_SUPPLY_PROP_PRESENT:
196                 val->intval = acpi_battery_present(battery);
197                 break;
198         case POWER_SUPPLY_PROP_TECHNOLOGY:
199                 val->intval = acpi_battery_technology(battery);
200                 break;
201         case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
202                 val->intval = battery->design_voltage * 1000;
203                 break;
204         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
205                 val->intval = battery->voltage_now * 1000;
206                 break;
207         case POWER_SUPPLY_PROP_CURRENT_NOW:
208         case POWER_SUPPLY_PROP_POWER_NOW:
209                 val->intval = battery->rate_now * 1000;
210                 break;
211         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
212         case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
213                 val->intval = battery->design_capacity * 1000;
214                 break;
215         case POWER_SUPPLY_PROP_CHARGE_FULL:
216         case POWER_SUPPLY_PROP_ENERGY_FULL:
217                 val->intval = battery->full_charge_capacity * 1000;
218                 break;
219         case POWER_SUPPLY_PROP_CHARGE_NOW:
220         case POWER_SUPPLY_PROP_ENERGY_NOW:
221                 val->intval = battery->capacity_now * 1000;
222                 break;
223         case POWER_SUPPLY_PROP_MODEL_NAME:
224                 val->strval = battery->model_number;
225                 break;
226         case POWER_SUPPLY_PROP_MANUFACTURER:
227                 val->strval = battery->oem_info;
228                 break;
229         case POWER_SUPPLY_PROP_SERIAL_NUMBER:
230                 val->strval = battery->serial_number;
231                 break;
232         default:
233                 return -EINVAL;
234         }
235         return 0;
236 }
237
238 static enum power_supply_property charge_battery_props[] = {
239         POWER_SUPPLY_PROP_STATUS,
240         POWER_SUPPLY_PROP_PRESENT,
241         POWER_SUPPLY_PROP_TECHNOLOGY,
242         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
243         POWER_SUPPLY_PROP_VOLTAGE_NOW,
244         POWER_SUPPLY_PROP_CURRENT_NOW,
245         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
246         POWER_SUPPLY_PROP_CHARGE_FULL,
247         POWER_SUPPLY_PROP_CHARGE_NOW,
248         POWER_SUPPLY_PROP_MODEL_NAME,
249         POWER_SUPPLY_PROP_MANUFACTURER,
250         POWER_SUPPLY_PROP_SERIAL_NUMBER,
251 };
252
253 static enum power_supply_property energy_battery_props[] = {
254         POWER_SUPPLY_PROP_STATUS,
255         POWER_SUPPLY_PROP_PRESENT,
256         POWER_SUPPLY_PROP_TECHNOLOGY,
257         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
258         POWER_SUPPLY_PROP_VOLTAGE_NOW,
259         POWER_SUPPLY_PROP_CURRENT_NOW,
260         POWER_SUPPLY_PROP_POWER_NOW,
261         POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
262         POWER_SUPPLY_PROP_ENERGY_FULL,
263         POWER_SUPPLY_PROP_ENERGY_NOW,
264         POWER_SUPPLY_PROP_MODEL_NAME,
265         POWER_SUPPLY_PROP_MANUFACTURER,
266         POWER_SUPPLY_PROP_SERIAL_NUMBER,
267 };
268 #endif
269
270 #ifdef CONFIG_ACPI_PROCFS_POWER
271 inline char *acpi_battery_units(struct acpi_battery *battery)
272 {
273         return (battery->power_unit)?"mA":"mW";
274 }
275 #endif
276
277 /* --------------------------------------------------------------------------
278                                Battery Management
279    -------------------------------------------------------------------------- */
280 struct acpi_offsets {
281         size_t offset;          /* offset inside struct acpi_sbs_battery */
282         u8 mode;                /* int or string? */
283 };
284
285 static struct acpi_offsets state_offsets[] = {
286         {offsetof(struct acpi_battery, state), 0},
287         {offsetof(struct acpi_battery, rate_now), 0},
288         {offsetof(struct acpi_battery, capacity_now), 0},
289         {offsetof(struct acpi_battery, voltage_now), 0},
290 };
291
292 static struct acpi_offsets info_offsets[] = {
293         {offsetof(struct acpi_battery, power_unit), 0},
294         {offsetof(struct acpi_battery, design_capacity), 0},
295         {offsetof(struct acpi_battery, full_charge_capacity), 0},
296         {offsetof(struct acpi_battery, technology), 0},
297         {offsetof(struct acpi_battery, design_voltage), 0},
298         {offsetof(struct acpi_battery, design_capacity_warning), 0},
299         {offsetof(struct acpi_battery, design_capacity_low), 0},
300         {offsetof(struct acpi_battery, capacity_granularity_1), 0},
301         {offsetof(struct acpi_battery, capacity_granularity_2), 0},
302         {offsetof(struct acpi_battery, model_number), 1},
303         {offsetof(struct acpi_battery, serial_number), 1},
304         {offsetof(struct acpi_battery, type), 1},
305         {offsetof(struct acpi_battery, oem_info), 1},
306 };
307
308 static int extract_package(struct acpi_battery *battery,
309                            union acpi_object *package,
310                            struct acpi_offsets *offsets, int num)
311 {
312         int i;
313         union acpi_object *element;
314         if (package->type != ACPI_TYPE_PACKAGE)
315                 return -EFAULT;
316         for (i = 0; i < num; ++i) {
317                 if (package->package.count <= i)
318                         return -EFAULT;
319                 element = &package->package.elements[i];
320                 if (offsets[i].mode) {
321                         u8 *ptr = (u8 *)battery + offsets[i].offset;
322                         if (element->type == ACPI_TYPE_STRING ||
323                             element->type == ACPI_TYPE_BUFFER)
324                                 strncpy(ptr, element->string.pointer, 32);
325                         else if (element->type == ACPI_TYPE_INTEGER) {
326                                 strncpy(ptr, (u8 *)&element->integer.value,
327                                         sizeof(acpi_integer));
328                                 ptr[sizeof(acpi_integer)] = 0;
329                         } else
330                                 *ptr = 0; /* don't have value */
331                 } else {
332                         int *x = (int *)((u8 *)battery + offsets[i].offset);
333                         *x = (element->type == ACPI_TYPE_INTEGER) ?
334                                 element->integer.value : -1;
335                 }
336         }
337         return 0;
338 }
339
340 static int acpi_battery_get_status(struct acpi_battery *battery)
341 {
342         if (acpi_bus_get_status(battery->device)) {
343                 ACPI_EXCEPTION((AE_INFO, AE_ERROR, "Evaluating _STA"));
344                 return -ENODEV;
345         }
346         return 0;
347 }
348
349 static int acpi_battery_get_info(struct acpi_battery *battery)
350 {
351         int result = -EFAULT;
352         acpi_status status = 0;
353         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
354
355         if (!acpi_battery_present(battery))
356                 return 0;
357         mutex_lock(&battery->lock);
358         status = acpi_evaluate_object(battery->device->handle, "_BIF",
359                                       NULL, &buffer);
360         mutex_unlock(&battery->lock);
361
362         if (ACPI_FAILURE(status)) {
363                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BIF"));
364                 return -ENODEV;
365         }
366
367         result = extract_package(battery, buffer.pointer,
368                                  info_offsets, ARRAY_SIZE(info_offsets));
369         kfree(buffer.pointer);
370         return result;
371 }
372
373 static int acpi_battery_get_state(struct acpi_battery *battery)
374 {
375         int result = 0;
376         acpi_status status = 0;
377         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
378
379         if (!acpi_battery_present(battery))
380                 return 0;
381
382         if (battery->update_time &&
383             time_before(jiffies, battery->update_time +
384                         msecs_to_jiffies(cache_time)))
385                 return 0;
386
387         mutex_lock(&battery->lock);
388         status = acpi_evaluate_object(battery->device->handle, "_BST",
389                                       NULL, &buffer);
390         mutex_unlock(&battery->lock);
391
392         if (ACPI_FAILURE(status)) {
393                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BST"));
394                 return -ENODEV;
395         }
396
397         result = extract_package(battery, buffer.pointer,
398                                  state_offsets, ARRAY_SIZE(state_offsets));
399         battery->update_time = jiffies;
400         kfree(buffer.pointer);
401
402         if ((battery->quirks & QUIRK_SIGNED16_CURRENT) &&
403             battery->rate_now != -1)
404                 battery->rate_now = abs((s16)battery->rate_now);
405
406         return result;
407 }
408
409 static int acpi_battery_set_alarm(struct acpi_battery *battery)
410 {
411         acpi_status status = 0;
412         union acpi_object arg0 = { .type = ACPI_TYPE_INTEGER };
413         struct acpi_object_list arg_list = { 1, &arg0 };
414
415         if (!acpi_battery_present(battery)|| !battery->alarm_present)
416                 return -ENODEV;
417
418         arg0.integer.value = battery->alarm;
419
420         mutex_lock(&battery->lock);
421         status = acpi_evaluate_object(battery->device->handle, "_BTP",
422                                  &arg_list, NULL);
423         mutex_unlock(&battery->lock);
424
425         if (ACPI_FAILURE(status))
426                 return -ENODEV;
427
428         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Alarm set to %d\n", battery->alarm));
429         return 0;
430 }
431
432 static int acpi_battery_init_alarm(struct acpi_battery *battery)
433 {
434         acpi_status status = AE_OK;
435         acpi_handle handle = NULL;
436
437         /* See if alarms are supported, and if so, set default */
438         status = acpi_get_handle(battery->device->handle, "_BTP", &handle);
439         if (ACPI_FAILURE(status)) {
440                 battery->alarm_present = 0;
441                 return 0;
442         }
443         battery->alarm_present = 1;
444         if (!battery->alarm)
445                 battery->alarm = battery->design_capacity_warning;
446         return acpi_battery_set_alarm(battery);
447 }
448
449 #ifdef CONFIG_ACPI_SYSFS_POWER
450 static ssize_t acpi_battery_alarm_show(struct device *dev,
451                                         struct device_attribute *attr,
452                                         char *buf)
453 {
454         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
455         return sprintf(buf, "%d\n", battery->alarm * 1000);
456 }
457
458 static ssize_t acpi_battery_alarm_store(struct device *dev,
459                                         struct device_attribute *attr,
460                                         const char *buf, size_t count)
461 {
462         unsigned long x;
463         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
464         if (sscanf(buf, "%ld\n", &x) == 1)
465                 battery->alarm = x/1000;
466         if (acpi_battery_present(battery))
467                 acpi_battery_set_alarm(battery);
468         return count;
469 }
470
471 static struct device_attribute alarm_attr = {
472         .attr = {.name = "alarm", .mode = 0644},
473         .show = acpi_battery_alarm_show,
474         .store = acpi_battery_alarm_store,
475 };
476
477 static int sysfs_add_battery(struct acpi_battery *battery)
478 {
479         int result;
480
481         if (battery->power_unit) {
482                 battery->bat.properties = charge_battery_props;
483                 battery->bat.num_properties =
484                         ARRAY_SIZE(charge_battery_props);
485         } else {
486                 battery->bat.properties = energy_battery_props;
487                 battery->bat.num_properties =
488                         ARRAY_SIZE(energy_battery_props);
489         }
490
491         battery->bat.name = acpi_device_bid(battery->device);
492         battery->bat.type = POWER_SUPPLY_TYPE_BATTERY;
493         battery->bat.get_property = acpi_battery_get_property;
494
495         result = power_supply_register(&battery->device->dev, &battery->bat);
496         if (result)
497                 return result;
498         return device_create_file(battery->bat.dev, &alarm_attr);
499 }
500
501 static void sysfs_remove_battery(struct acpi_battery *battery)
502 {
503         if (!battery->bat.dev)
504                 return;
505         device_remove_file(battery->bat.dev, &alarm_attr);
506         power_supply_unregister(&battery->bat);
507         battery->bat.dev = NULL;
508 }
509 #endif
510
511 static void acpi_battery_quirks(struct acpi_battery *battery)
512 {
513         battery->quirks = 0;
514         if (dmi_name_in_vendors("Acer") && battery->power_unit) {
515                 battery->quirks |= QUIRK_SIGNED16_CURRENT;
516         }
517 }
518
519 static int acpi_battery_update(struct acpi_battery *battery)
520 {
521         int result, old_present = acpi_battery_present(battery);
522         result = acpi_battery_get_status(battery);
523         if (result)
524                 return result;
525 #ifdef CONFIG_ACPI_SYSFS_POWER
526         if (!acpi_battery_present(battery)) {
527                 sysfs_remove_battery(battery);
528                 battery->update_time = 0;
529                 return 0;
530         }
531 #endif
532         if (!battery->update_time ||
533             old_present != acpi_battery_present(battery)) {
534                 result = acpi_battery_get_info(battery);
535                 if (result)
536                         return result;
537                 acpi_battery_quirks(battery);
538                 acpi_battery_init_alarm(battery);
539         }
540 #ifdef CONFIG_ACPI_SYSFS_POWER
541         if (!battery->bat.dev)
542                 sysfs_add_battery(battery);
543 #endif
544         return acpi_battery_get_state(battery);
545 }
546
547 /* --------------------------------------------------------------------------
548                               FS Interface (/proc)
549    -------------------------------------------------------------------------- */
550
551 #ifdef CONFIG_ACPI_PROCFS_POWER
552 static struct proc_dir_entry *acpi_battery_dir;
553
554 static int acpi_battery_print_info(struct seq_file *seq, int result)
555 {
556         struct acpi_battery *battery = seq->private;
557
558         if (result)
559                 goto end;
560
561         seq_printf(seq, "present:                 %s\n",
562                    acpi_battery_present(battery)?"yes":"no");
563         if (!acpi_battery_present(battery))
564                 goto end;
565         if (battery->design_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
566                 seq_printf(seq, "design capacity:         unknown\n");
567         else
568                 seq_printf(seq, "design capacity:         %d %sh\n",
569                            battery->design_capacity,
570                            acpi_battery_units(battery));
571
572         if (battery->full_charge_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
573                 seq_printf(seq, "last full capacity:      unknown\n");
574         else
575                 seq_printf(seq, "last full capacity:      %d %sh\n",
576                            battery->full_charge_capacity,
577                            acpi_battery_units(battery));
578
579         seq_printf(seq, "battery technology:      %srechargeable\n",
580                    (!battery->technology)?"non-":"");
581
582         if (battery->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
583                 seq_printf(seq, "design voltage:          unknown\n");
584         else
585                 seq_printf(seq, "design voltage:          %d mV\n",
586                            battery->design_voltage);
587         seq_printf(seq, "design capacity warning: %d %sh\n",
588                    battery->design_capacity_warning,
589                    acpi_battery_units(battery));
590         seq_printf(seq, "design capacity low:     %d %sh\n",
591                    battery->design_capacity_low,
592                    acpi_battery_units(battery));
593         seq_printf(seq, "capacity granularity 1:  %d %sh\n",
594                    battery->capacity_granularity_1,
595                    acpi_battery_units(battery));
596         seq_printf(seq, "capacity granularity 2:  %d %sh\n",
597                    battery->capacity_granularity_2,
598                    acpi_battery_units(battery));
599         seq_printf(seq, "model number:            %s\n", battery->model_number);
600         seq_printf(seq, "serial number:           %s\n", battery->serial_number);
601         seq_printf(seq, "battery type:            %s\n", battery->type);
602         seq_printf(seq, "OEM info:                %s\n", battery->oem_info);
603       end:
604         if (result)
605                 seq_printf(seq, "ERROR: Unable to read battery info\n");
606         return result;
607 }
608
609 static int acpi_battery_print_state(struct seq_file *seq, int result)
610 {
611         struct acpi_battery *battery = seq->private;
612
613         if (result)
614                 goto end;
615
616         seq_printf(seq, "present:                 %s\n",
617                    acpi_battery_present(battery)?"yes":"no");
618         if (!acpi_battery_present(battery))
619                 goto end;
620
621         seq_printf(seq, "capacity state:          %s\n",
622                         (battery->state & 0x04)?"critical":"ok");
623         if ((battery->state & 0x01) && (battery->state & 0x02))
624                 seq_printf(seq,
625                            "charging state:          charging/discharging\n");
626         else if (battery->state & 0x01)
627                 seq_printf(seq, "charging state:          discharging\n");
628         else if (battery->state & 0x02)
629                 seq_printf(seq, "charging state:          charging\n");
630         else
631                 seq_printf(seq, "charging state:          charged\n");
632
633         if (battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN)
634                 seq_printf(seq, "present rate:            unknown\n");
635         else
636                 seq_printf(seq, "present rate:            %d %s\n",
637                            battery->rate_now, acpi_battery_units(battery));
638
639         if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN)
640                 seq_printf(seq, "remaining capacity:      unknown\n");
641         else
642                 seq_printf(seq, "remaining capacity:      %d %sh\n",
643                            battery->capacity_now, acpi_battery_units(battery));
644         if (battery->voltage_now == ACPI_BATTERY_VALUE_UNKNOWN)
645                 seq_printf(seq, "present voltage:         unknown\n");
646         else
647                 seq_printf(seq, "present voltage:         %d mV\n",
648                            battery->voltage_now);
649       end:
650         if (result)
651                 seq_printf(seq, "ERROR: Unable to read battery state\n");
652
653         return result;
654 }
655
656 static int acpi_battery_print_alarm(struct seq_file *seq, int result)
657 {
658         struct acpi_battery *battery = seq->private;
659
660         if (result)
661                 goto end;
662
663         if (!acpi_battery_present(battery)) {
664                 seq_printf(seq, "present:                 no\n");
665                 goto end;
666         }
667         seq_printf(seq, "alarm:                   ");
668         if (!battery->alarm)
669                 seq_printf(seq, "unsupported\n");
670         else
671                 seq_printf(seq, "%u %sh\n", battery->alarm,
672                                 acpi_battery_units(battery));
673       end:
674         if (result)
675                 seq_printf(seq, "ERROR: Unable to read battery alarm\n");
676         return result;
677 }
678
679 static ssize_t acpi_battery_write_alarm(struct file *file,
680                                         const char __user * buffer,
681                                         size_t count, loff_t * ppos)
682 {
683         int result = 0;
684         char alarm_string[12] = { '\0' };
685         struct seq_file *m = file->private_data;
686         struct acpi_battery *battery = m->private;
687
688         if (!battery || (count > sizeof(alarm_string) - 1))
689                 return -EINVAL;
690         if (!acpi_battery_present(battery)) {
691                 result = -ENODEV;
692                 goto end;
693         }
694         if (copy_from_user(alarm_string, buffer, count)) {
695                 result = -EFAULT;
696                 goto end;
697         }
698         alarm_string[count] = '\0';
699         battery->alarm = simple_strtol(alarm_string, NULL, 0);
700         result = acpi_battery_set_alarm(battery);
701       end:
702         if (!result)
703                 return count;
704         return result;
705 }
706
707 typedef int(*print_func)(struct seq_file *seq, int result);
708
709 static print_func acpi_print_funcs[ACPI_BATTERY_NUMFILES] = {
710         acpi_battery_print_info,
711         acpi_battery_print_state,
712         acpi_battery_print_alarm,
713 };
714
715 static int acpi_battery_read(int fid, struct seq_file *seq)
716 {
717         struct acpi_battery *battery = seq->private;
718         int result = acpi_battery_update(battery);
719         return acpi_print_funcs[fid](seq, result);
720 }
721
722 #define DECLARE_FILE_FUNCTIONS(_name) \
723 static int acpi_battery_read_##_name(struct seq_file *seq, void *offset) \
724 { \
725         return acpi_battery_read(_name##_tag, seq); \
726 } \
727 static int acpi_battery_##_name##_open_fs(struct inode *inode, struct file *file) \
728 { \
729         return single_open(file, acpi_battery_read_##_name, PDE(inode)->data); \
730 }
731
732 DECLARE_FILE_FUNCTIONS(info);
733 DECLARE_FILE_FUNCTIONS(state);
734 DECLARE_FILE_FUNCTIONS(alarm);
735
736 #undef DECLARE_FILE_FUNCTIONS
737
738 #define FILE_DESCRIPTION_RO(_name) \
739         { \
740         .name = __stringify(_name), \
741         .mode = S_IRUGO, \
742         .ops = { \
743                 .open = acpi_battery_##_name##_open_fs, \
744                 .read = seq_read, \
745                 .llseek = seq_lseek, \
746                 .release = single_release, \
747                 .owner = THIS_MODULE, \
748                 }, \
749         }
750
751 #define FILE_DESCRIPTION_RW(_name) \
752         { \
753         .name = __stringify(_name), \
754         .mode = S_IFREG | S_IRUGO | S_IWUSR, \
755         .ops = { \
756                 .open = acpi_battery_##_name##_open_fs, \
757                 .read = seq_read, \
758                 .llseek = seq_lseek, \
759                 .write = acpi_battery_write_##_name, \
760                 .release = single_release, \
761                 .owner = THIS_MODULE, \
762                 }, \
763         }
764
765 static struct battery_file {
766         struct file_operations ops;
767         mode_t mode;
768         const char *name;
769 } acpi_battery_file[] = {
770         FILE_DESCRIPTION_RO(info),
771         FILE_DESCRIPTION_RO(state),
772         FILE_DESCRIPTION_RW(alarm),
773 };
774
775 #undef FILE_DESCRIPTION_RO
776 #undef FILE_DESCRIPTION_RW
777
778 static int acpi_battery_add_fs(struct acpi_device *device)
779 {
780         struct proc_dir_entry *entry = NULL;
781         int i;
782
783         if (!acpi_device_dir(device)) {
784                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
785                                                      acpi_battery_dir);
786                 if (!acpi_device_dir(device))
787                         return -ENODEV;
788         }
789
790         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i) {
791                 entry = proc_create_data(acpi_battery_file[i].name,
792                                          acpi_battery_file[i].mode,
793                                          acpi_device_dir(device),
794                                          &acpi_battery_file[i].ops,
795                                          acpi_driver_data(device));
796                 if (!entry)
797                         return -ENODEV;
798         }
799         return 0;
800 }
801
802 static void acpi_battery_remove_fs(struct acpi_device *device)
803 {
804         int i;
805         if (!acpi_device_dir(device))
806                 return;
807         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i)
808                 remove_proc_entry(acpi_battery_file[i].name,
809                                   acpi_device_dir(device));
810
811         remove_proc_entry(acpi_device_bid(device), acpi_battery_dir);
812         acpi_device_dir(device) = NULL;
813 }
814
815 #endif
816
817 /* --------------------------------------------------------------------------
818                                  Driver Interface
819    -------------------------------------------------------------------------- */
820
821 static void acpi_battery_notify(struct acpi_device *device, u32 event)
822 {
823         struct acpi_battery *battery = acpi_driver_data(device);
824
825         if (!battery)
826                 return;
827         acpi_battery_update(battery);
828         acpi_bus_generate_proc_event(device, event,
829                                      acpi_battery_present(battery));
830         acpi_bus_generate_netlink_event(device->pnp.device_class,
831                                         dev_name(&device->dev), event,
832                                         acpi_battery_present(battery));
833 #ifdef CONFIG_ACPI_SYSFS_POWER
834         /* acpi_batter_update could remove power_supply object */
835         if (battery->bat.dev)
836                 kobject_uevent(&battery->bat.dev->kobj, KOBJ_CHANGE);
837 #endif
838 }
839
840 static int acpi_battery_add(struct acpi_device *device)
841 {
842         int result = 0;
843         struct acpi_battery *battery = NULL;
844         if (!device)
845                 return -EINVAL;
846         battery = kzalloc(sizeof(struct acpi_battery), GFP_KERNEL);
847         if (!battery)
848                 return -ENOMEM;
849         battery->device = device;
850         strcpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
851         strcpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
852         device->driver_data = battery;
853         mutex_init(&battery->lock);
854         acpi_battery_update(battery);
855 #ifdef CONFIG_ACPI_PROCFS_POWER
856         result = acpi_battery_add_fs(device);
857 #endif
858         if (!result) {
859                 printk(KERN_INFO PREFIX "%s Slot [%s] (battery %s)\n",
860                         ACPI_BATTERY_DEVICE_NAME, acpi_device_bid(device),
861                         device->status.battery_present ? "present" : "absent");
862         } else {
863 #ifdef CONFIG_ACPI_PROCFS_POWER
864                 acpi_battery_remove_fs(device);
865 #endif
866                 kfree(battery);
867         }
868         return result;
869 }
870
871 static int acpi_battery_remove(struct acpi_device *device, int type)
872 {
873         struct acpi_battery *battery = NULL;
874
875         if (!device || !acpi_driver_data(device))
876                 return -EINVAL;
877         battery = acpi_driver_data(device);
878 #ifdef CONFIG_ACPI_PROCFS_POWER
879         acpi_battery_remove_fs(device);
880 #endif
881 #ifdef CONFIG_ACPI_SYSFS_POWER
882         sysfs_remove_battery(battery);
883 #endif
884         mutex_destroy(&battery->lock);
885         kfree(battery);
886         return 0;
887 }
888
889 /* this is needed to learn about changes made in suspended state */
890 static int acpi_battery_resume(struct acpi_device *device)
891 {
892         struct acpi_battery *battery;
893         if (!device)
894                 return -EINVAL;
895         battery = acpi_driver_data(device);
896         battery->update_time = 0;
897         acpi_battery_update(battery);
898         return 0;
899 }
900
901 static struct acpi_driver acpi_battery_driver = {
902         .name = "battery",
903         .class = ACPI_BATTERY_CLASS,
904         .ids = battery_device_ids,
905         .flags = ACPI_DRIVER_ALL_NOTIFY_EVENTS,
906         .ops = {
907                 .add = acpi_battery_add,
908                 .resume = acpi_battery_resume,
909                 .remove = acpi_battery_remove,
910                 .notify = acpi_battery_notify,
911                 },
912 };
913
914 static void __init acpi_battery_init_async(void *unused, async_cookie_t cookie)
915 {
916         if (acpi_disabled)
917                 return;
918 #ifdef CONFIG_ACPI_PROCFS_POWER
919         acpi_battery_dir = acpi_lock_battery_dir();
920         if (!acpi_battery_dir)
921                 return;
922 #endif
923         if (acpi_bus_register_driver(&acpi_battery_driver) < 0) {
924 #ifdef CONFIG_ACPI_PROCFS_POWER
925                 acpi_unlock_battery_dir(acpi_battery_dir);
926 #endif
927                 return;
928         }
929         return;
930 }
931
932 static int __init acpi_battery_init(void)
933 {
934         async_schedule(acpi_battery_init_async, NULL);
935         return 0;
936 }
937
938 static void __exit acpi_battery_exit(void)
939 {
940         acpi_bus_unregister_driver(&acpi_battery_driver);
941 #ifdef CONFIG_ACPI_PROCFS_POWER
942         acpi_unlock_battery_dir(acpi_battery_dir);
943 #endif
944 }
945
946 module_init(acpi_battery_init);
947 module_exit(acpi_battery_exit);