ACPI: Make sysfs interface in ACPI power optional.
[linux-3.10.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
34 #ifdef CONFIG_ACPI_PROCFS_POWER
35 #include <linux/proc_fs.h>
36 #include <linux/seq_file.h>
37 #include <asm/uaccess.h>
38 #endif
39
40 #include <acpi/acpi_bus.h>
41 #include <acpi/acpi_drivers.h>
42
43 #ifdef CONFIG_ACPI_SYSFS_POWER
44 #include <linux/power_supply.h>
45 #endif
46
47 #define ACPI_BATTERY_VALUE_UNKNOWN 0xFFFFFFFF
48
49 #define ACPI_BATTERY_COMPONENT          0x00040000
50 #define ACPI_BATTERY_CLASS              "battery"
51 #define ACPI_BATTERY_DEVICE_NAME        "Battery"
52 #define ACPI_BATTERY_NOTIFY_STATUS      0x80
53 #define ACPI_BATTERY_NOTIFY_INFO        0x81
54
55 #define _COMPONENT              ACPI_BATTERY_COMPONENT
56
57 ACPI_MODULE_NAME("battery");
58
59 MODULE_AUTHOR("Paul Diefenbaugh");
60 MODULE_AUTHOR("Alexey Starikovskiy <astarikovskiy@suse.de>");
61 MODULE_DESCRIPTION("ACPI Battery Driver");
62 MODULE_LICENSE("GPL");
63
64 static unsigned int cache_time = 1000;
65 module_param(cache_time, uint, 0644);
66 MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
67
68 #ifdef CONFIG_ACPI_PROCFS_POWER
69 extern struct proc_dir_entry *acpi_lock_battery_dir(void);
70 extern void *acpi_unlock_battery_dir(struct proc_dir_entry *acpi_battery_dir);
71
72 enum acpi_battery_files {
73         info_tag = 0,
74         state_tag,
75         alarm_tag,
76         ACPI_BATTERY_NUMFILES,
77 };
78
79 #endif
80
81 static const struct acpi_device_id battery_device_ids[] = {
82         {"PNP0C0A", 0},
83         {"", 0},
84 };
85
86 MODULE_DEVICE_TABLE(acpi, battery_device_ids);
87
88
89 struct acpi_battery {
90         struct mutex lock;
91 #ifdef CONFIG_ACPI_SYSFS_POWER
92         struct power_supply bat;
93 #endif
94         struct acpi_device *device;
95         unsigned long update_time;
96         int current_now;
97         int capacity_now;
98         int voltage_now;
99         int design_capacity;
100         int full_charge_capacity;
101         int technology;
102         int design_voltage;
103         int design_capacity_warning;
104         int design_capacity_low;
105         int capacity_granularity_1;
106         int capacity_granularity_2;
107         int alarm;
108         char model_number[32];
109         char serial_number[32];
110         char type[32];
111         char oem_info[32];
112         int state;
113         int power_unit;
114         u8 alarm_present;
115 };
116
117 #define to_acpi_battery(x) container_of(x, struct acpi_battery, bat);
118
119 inline int acpi_battery_present(struct acpi_battery *battery)
120 {
121         return battery->device->status.battery_present;
122 }
123
124 #ifdef CONFIG_ACPI_SYSFS_POWER
125 static int acpi_battery_technology(struct acpi_battery *battery)
126 {
127         if (!strcasecmp("NiCd", battery->type))
128                 return POWER_SUPPLY_TECHNOLOGY_NiCd;
129         if (!strcasecmp("NiMH", battery->type))
130                 return POWER_SUPPLY_TECHNOLOGY_NiMH;
131         if (!strcasecmp("LION", battery->type))
132                 return POWER_SUPPLY_TECHNOLOGY_LION;
133         if (!strncasecmp("LI-ION", battery->type, 6))
134                 return POWER_SUPPLY_TECHNOLOGY_LION;
135         if (!strcasecmp("LiP", battery->type))
136                 return POWER_SUPPLY_TECHNOLOGY_LIPO;
137         return POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
138 }
139
140 static int acpi_battery_get_state(struct acpi_battery *battery);
141
142 static int acpi_battery_get_property(struct power_supply *psy,
143                                      enum power_supply_property psp,
144                                      union power_supply_propval *val)
145 {
146         struct acpi_battery *battery = to_acpi_battery(psy);
147
148         if (acpi_battery_present(battery)) {
149                 /* run battery update only if it is present */
150                 acpi_battery_get_state(battery);
151         } else if (psp != POWER_SUPPLY_PROP_PRESENT)
152                 return -ENODEV;
153         switch (psp) {
154         case POWER_SUPPLY_PROP_STATUS:
155                 if (battery->state & 0x01)
156                         val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
157                 else if (battery->state & 0x02)
158                         val->intval = POWER_SUPPLY_STATUS_CHARGING;
159                 else if (battery->state == 0)
160                         val->intval = POWER_SUPPLY_STATUS_FULL;
161                 else
162                         val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
163                 break;
164         case POWER_SUPPLY_PROP_PRESENT:
165                 val->intval = acpi_battery_present(battery);
166                 break;
167         case POWER_SUPPLY_PROP_TECHNOLOGY:
168                 val->intval = acpi_battery_technology(battery);
169                 break;
170         case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
171                 val->intval = battery->design_voltage * 1000;
172                 break;
173         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
174                 val->intval = battery->voltage_now * 1000;
175                 break;
176         case POWER_SUPPLY_PROP_CURRENT_NOW:
177                 val->intval = battery->current_now * 1000;
178                 break;
179         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
180         case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
181                 val->intval = battery->design_capacity * 1000;
182                 break;
183         case POWER_SUPPLY_PROP_CHARGE_FULL:
184         case POWER_SUPPLY_PROP_ENERGY_FULL:
185                 val->intval = battery->full_charge_capacity * 1000;
186                 break;
187         case POWER_SUPPLY_PROP_CHARGE_NOW:
188         case POWER_SUPPLY_PROP_ENERGY_NOW:
189                 val->intval = battery->capacity_now * 1000;
190                 break;
191         case POWER_SUPPLY_PROP_MODEL_NAME:
192                 val->strval = battery->model_number;
193                 break;
194         case POWER_SUPPLY_PROP_MANUFACTURER:
195                 val->strval = battery->oem_info;
196                 break;
197         default:
198                 return -EINVAL;
199         }
200         return 0;
201 }
202
203 static enum power_supply_property charge_battery_props[] = {
204         POWER_SUPPLY_PROP_STATUS,
205         POWER_SUPPLY_PROP_PRESENT,
206         POWER_SUPPLY_PROP_TECHNOLOGY,
207         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
208         POWER_SUPPLY_PROP_VOLTAGE_NOW,
209         POWER_SUPPLY_PROP_CURRENT_NOW,
210         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
211         POWER_SUPPLY_PROP_CHARGE_FULL,
212         POWER_SUPPLY_PROP_CHARGE_NOW,
213         POWER_SUPPLY_PROP_MODEL_NAME,
214         POWER_SUPPLY_PROP_MANUFACTURER,
215 };
216
217 static enum power_supply_property energy_battery_props[] = {
218         POWER_SUPPLY_PROP_STATUS,
219         POWER_SUPPLY_PROP_PRESENT,
220         POWER_SUPPLY_PROP_TECHNOLOGY,
221         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
222         POWER_SUPPLY_PROP_VOLTAGE_NOW,
223         POWER_SUPPLY_PROP_CURRENT_NOW,
224         POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
225         POWER_SUPPLY_PROP_ENERGY_FULL,
226         POWER_SUPPLY_PROP_ENERGY_NOW,
227         POWER_SUPPLY_PROP_MODEL_NAME,
228         POWER_SUPPLY_PROP_MANUFACTURER,
229 };
230 #endif
231
232 #ifdef CONFIG_ACPI_PROCFS_POWER
233 inline char *acpi_battery_units(struct acpi_battery *battery)
234 {
235         return (battery->power_unit)?"mA":"mW";
236 }
237 #endif
238
239 /* --------------------------------------------------------------------------
240                                Battery Management
241    -------------------------------------------------------------------------- */
242 struct acpi_offsets {
243         size_t offset;          /* offset inside struct acpi_sbs_battery */
244         u8 mode;                /* int or string? */
245 };
246
247 static struct acpi_offsets state_offsets[] = {
248         {offsetof(struct acpi_battery, state), 0},
249         {offsetof(struct acpi_battery, current_now), 0},
250         {offsetof(struct acpi_battery, capacity_now), 0},
251         {offsetof(struct acpi_battery, voltage_now), 0},
252 };
253
254 static struct acpi_offsets info_offsets[] = {
255         {offsetof(struct acpi_battery, power_unit), 0},
256         {offsetof(struct acpi_battery, design_capacity), 0},
257         {offsetof(struct acpi_battery, full_charge_capacity), 0},
258         {offsetof(struct acpi_battery, technology), 0},
259         {offsetof(struct acpi_battery, design_voltage), 0},
260         {offsetof(struct acpi_battery, design_capacity_warning), 0},
261         {offsetof(struct acpi_battery, design_capacity_low), 0},
262         {offsetof(struct acpi_battery, capacity_granularity_1), 0},
263         {offsetof(struct acpi_battery, capacity_granularity_2), 0},
264         {offsetof(struct acpi_battery, model_number), 1},
265         {offsetof(struct acpi_battery, serial_number), 1},
266         {offsetof(struct acpi_battery, type), 1},
267         {offsetof(struct acpi_battery, oem_info), 1},
268 };
269
270 static int extract_package(struct acpi_battery *battery,
271                            union acpi_object *package,
272                            struct acpi_offsets *offsets, int num)
273 {
274         int i;
275         union acpi_object *element;
276         if (package->type != ACPI_TYPE_PACKAGE)
277                 return -EFAULT;
278         for (i = 0; i < num; ++i) {
279                 if (package->package.count <= i)
280                         return -EFAULT;
281                 element = &package->package.elements[i];
282                 if (offsets[i].mode) {
283                         u8 *ptr = (u8 *)battery + offsets[i].offset;
284                         if (element->type == ACPI_TYPE_STRING ||
285                             element->type == ACPI_TYPE_BUFFER)
286                                 strncpy(ptr, element->string.pointer, 32);
287                         else if (element->type == ACPI_TYPE_INTEGER) {
288                                 strncpy(ptr, (u8 *)&element->integer.value,
289                                         sizeof(acpi_integer));
290                                 ptr[sizeof(acpi_integer)] = 0;
291                         } else return -EFAULT;
292                 } else {
293                         if (element->type == ACPI_TYPE_INTEGER) {
294                                 int *x = (int *)((u8 *)battery +
295                                                 offsets[i].offset);
296                                 *x = element->integer.value;
297                         } else return -EFAULT;
298                 }
299         }
300         return 0;
301 }
302
303 static int acpi_battery_get_status(struct acpi_battery *battery)
304 {
305         if (acpi_bus_get_status(battery->device)) {
306                 ACPI_EXCEPTION((AE_INFO, AE_ERROR, "Evaluating _STA"));
307                 return -ENODEV;
308         }
309         return 0;
310 }
311
312 static int acpi_battery_get_info(struct acpi_battery *battery)
313 {
314         int result = -EFAULT;
315         acpi_status status = 0;
316         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
317
318         if (!acpi_battery_present(battery))
319                 return 0;
320         mutex_lock(&battery->lock);
321         status = acpi_evaluate_object(battery->device->handle, "_BIF",
322                                       NULL, &buffer);
323         mutex_unlock(&battery->lock);
324
325         if (ACPI_FAILURE(status)) {
326                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BIF"));
327                 return -ENODEV;
328         }
329
330         result = extract_package(battery, buffer.pointer,
331                                  info_offsets, ARRAY_SIZE(info_offsets));
332         kfree(buffer.pointer);
333         return result;
334 }
335
336 static int acpi_battery_get_state(struct acpi_battery *battery)
337 {
338         int result = 0;
339         acpi_status status = 0;
340         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
341
342         if (!acpi_battery_present(battery))
343                 return 0;
344
345         if (battery->update_time &&
346             time_before(jiffies, battery->update_time +
347                         msecs_to_jiffies(cache_time)))
348                 return 0;
349
350         mutex_lock(&battery->lock);
351         status = acpi_evaluate_object(battery->device->handle, "_BST",
352                                       NULL, &buffer);
353         mutex_unlock(&battery->lock);
354
355         if (ACPI_FAILURE(status)) {
356                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BST"));
357                 return -ENODEV;
358         }
359
360         result = extract_package(battery, buffer.pointer,
361                                  state_offsets, ARRAY_SIZE(state_offsets));
362         battery->update_time = jiffies;
363         kfree(buffer.pointer);
364         return result;
365 }
366
367 static int acpi_battery_set_alarm(struct acpi_battery *battery)
368 {
369         acpi_status status = 0;
370         union acpi_object arg0 = { .type = ACPI_TYPE_INTEGER };
371         struct acpi_object_list arg_list = { 1, &arg0 };
372
373         if (!acpi_battery_present(battery)|| !battery->alarm_present)
374                 return -ENODEV;
375
376         arg0.integer.value = battery->alarm;
377
378         mutex_lock(&battery->lock);
379         status = acpi_evaluate_object(battery->device->handle, "_BTP",
380                                  &arg_list, NULL);
381         mutex_unlock(&battery->lock);
382
383         if (ACPI_FAILURE(status))
384                 return -ENODEV;
385
386         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Alarm set to %d\n", battery->alarm));
387         return 0;
388 }
389
390 static int acpi_battery_init_alarm(struct acpi_battery *battery)
391 {
392         acpi_status status = AE_OK;
393         acpi_handle handle = NULL;
394
395         /* See if alarms are supported, and if so, set default */
396         status = acpi_get_handle(battery->device->handle, "_BTP", &handle);
397         if (ACPI_FAILURE(status)) {
398                 battery->alarm_present = 0;
399                 return 0;
400         }
401         battery->alarm_present = 1;
402         if (!battery->alarm)
403                 battery->alarm = battery->design_capacity_warning;
404         return acpi_battery_set_alarm(battery);
405 }
406
407 #ifdef CONFIG_ACPI_SYSFS_POWER
408 static ssize_t acpi_battery_alarm_show(struct device *dev,
409                                         struct device_attribute *attr,
410                                         char *buf)
411 {
412         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
413         return sprintf(buf, "%d\n", battery->alarm * 1000);
414 }
415
416 static ssize_t acpi_battery_alarm_store(struct device *dev,
417                                         struct device_attribute *attr,
418                                         const char *buf, size_t count)
419 {
420         unsigned long x;
421         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
422         if (sscanf(buf, "%ld\n", &x) == 1)
423                 battery->alarm = x/1000;
424         if (acpi_battery_present(battery))
425                 acpi_battery_set_alarm(battery);
426         return count;
427 }
428
429 static struct device_attribute alarm_attr = {
430         .attr = {.name = "alarm", .mode = 0644, .owner = THIS_MODULE},
431         .show = acpi_battery_alarm_show,
432         .store = acpi_battery_alarm_store,
433 };
434
435 static int sysfs_add_battery(struct acpi_battery *battery)
436 {
437         int result;
438
439         if (battery->power_unit) {
440                 battery->bat.properties = charge_battery_props;
441                 battery->bat.num_properties =
442                         ARRAY_SIZE(charge_battery_props);
443         } else {
444                 battery->bat.properties = energy_battery_props;
445                 battery->bat.num_properties =
446                         ARRAY_SIZE(energy_battery_props);
447         }
448
449         battery->bat.name = acpi_device_bid(battery->device);
450         battery->bat.type = POWER_SUPPLY_TYPE_BATTERY;
451         battery->bat.get_property = acpi_battery_get_property;
452
453         result = power_supply_register(&battery->device->dev, &battery->bat);
454         if (result)
455                 return result;
456         return device_create_file(battery->bat.dev, &alarm_attr);
457 }
458
459 static void sysfs_remove_battery(struct acpi_battery *battery)
460 {
461         if (!battery->bat.dev)
462                 return;
463         device_remove_file(battery->bat.dev, &alarm_attr);
464         power_supply_unregister(&battery->bat);
465         battery->bat.dev = NULL;
466 }
467 #endif
468
469 static int acpi_battery_update(struct acpi_battery *battery)
470 {
471         int result;
472         result = acpi_battery_get_status(battery);
473         if (result)
474                 return result;
475 #ifdef CONFIG_ACPI_SYSFS_POWER
476         if (!acpi_battery_present(battery)) {
477                 sysfs_remove_battery(battery);
478                 battery->update_time = 0;
479                 return 0;
480         }
481 #endif
482         if (!battery->update_time) {
483                 result = acpi_battery_get_info(battery);
484                 if (result)
485                         return result;
486                 acpi_battery_init_alarm(battery);
487         }
488 #ifdef CONFIG_ACPI_SYSFS_POWER
489         if (!battery->bat.dev)
490                 sysfs_add_battery(battery);
491 #endif
492         return acpi_battery_get_state(battery);
493 }
494
495 /* --------------------------------------------------------------------------
496                               FS Interface (/proc)
497    -------------------------------------------------------------------------- */
498
499 #ifdef CONFIG_ACPI_PROCFS_POWER
500 static struct proc_dir_entry *acpi_battery_dir;
501
502 static int acpi_battery_print_info(struct seq_file *seq, int result)
503 {
504         struct acpi_battery *battery = seq->private;
505
506         if (result)
507                 goto end;
508
509         seq_printf(seq, "present:                 %s\n",
510                    acpi_battery_present(battery)?"yes":"no");
511         if (!acpi_battery_present(battery))
512                 goto end;
513         if (battery->design_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
514                 seq_printf(seq, "design capacity:         unknown\n");
515         else
516                 seq_printf(seq, "design capacity:         %d %sh\n",
517                            battery->design_capacity,
518                            acpi_battery_units(battery));
519
520         if (battery->full_charge_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
521                 seq_printf(seq, "last full capacity:      unknown\n");
522         else
523                 seq_printf(seq, "last full capacity:      %d %sh\n",
524                            battery->full_charge_capacity,
525                            acpi_battery_units(battery));
526
527         seq_printf(seq, "battery technology:      %srechargeable\n",
528                    (!battery->technology)?"non-":"");
529
530         if (battery->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
531                 seq_printf(seq, "design voltage:          unknown\n");
532         else
533                 seq_printf(seq, "design voltage:          %d mV\n",
534                            battery->design_voltage);
535         seq_printf(seq, "design capacity warning: %d %sh\n",
536                    battery->design_capacity_warning,
537                    acpi_battery_units(battery));
538         seq_printf(seq, "design capacity low:     %d %sh\n",
539                    battery->design_capacity_low,
540                    acpi_battery_units(battery));
541         seq_printf(seq, "capacity granularity 1:  %d %sh\n",
542                    battery->capacity_granularity_1,
543                    acpi_battery_units(battery));
544         seq_printf(seq, "capacity granularity 2:  %d %sh\n",
545                    battery->capacity_granularity_2,
546                    acpi_battery_units(battery));
547         seq_printf(seq, "model number:            %s\n", battery->model_number);
548         seq_printf(seq, "serial number:           %s\n", battery->serial_number);
549         seq_printf(seq, "battery type:            %s\n", battery->type);
550         seq_printf(seq, "OEM info:                %s\n", battery->oem_info);
551       end:
552         if (result)
553                 seq_printf(seq, "ERROR: Unable to read battery info\n");
554         return result;
555 }
556
557 static int acpi_battery_print_state(struct seq_file *seq, int result)
558 {
559         struct acpi_battery *battery = seq->private;
560
561         if (result)
562                 goto end;
563
564         seq_printf(seq, "present:                 %s\n",
565                    acpi_battery_present(battery)?"yes":"no");
566         if (!acpi_battery_present(battery))
567                 goto end;
568
569         seq_printf(seq, "capacity state:          %s\n",
570                         (battery->state & 0x04)?"critical":"ok");
571         if ((battery->state & 0x01) && (battery->state & 0x02))
572                 seq_printf(seq,
573                            "charging state:          charging/discharging\n");
574         else if (battery->state & 0x01)
575                 seq_printf(seq, "charging state:          discharging\n");
576         else if (battery->state & 0x02)
577                 seq_printf(seq, "charging state:          charging\n");
578         else
579                 seq_printf(seq, "charging state:          charged\n");
580
581         if (battery->current_now == ACPI_BATTERY_VALUE_UNKNOWN)
582                 seq_printf(seq, "present rate:            unknown\n");
583         else
584                 seq_printf(seq, "present rate:            %d %s\n",
585                            battery->current_now, acpi_battery_units(battery));
586
587         if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN)
588                 seq_printf(seq, "remaining capacity:      unknown\n");
589         else
590                 seq_printf(seq, "remaining capacity:      %d %sh\n",
591                            battery->capacity_now, acpi_battery_units(battery));
592         if (battery->voltage_now == ACPI_BATTERY_VALUE_UNKNOWN)
593                 seq_printf(seq, "present voltage:         unknown\n");
594         else
595                 seq_printf(seq, "present voltage:         %d mV\n",
596                            battery->voltage_now);
597       end:
598         if (result)
599                 seq_printf(seq, "ERROR: Unable to read battery state\n");
600
601         return result;
602 }
603
604 static int acpi_battery_print_alarm(struct seq_file *seq, int result)
605 {
606         struct acpi_battery *battery = seq->private;
607
608         if (result)
609                 goto end;
610
611         if (!acpi_battery_present(battery)) {
612                 seq_printf(seq, "present:                 no\n");
613                 goto end;
614         }
615         seq_printf(seq, "alarm:                   ");
616         if (!battery->alarm)
617                 seq_printf(seq, "unsupported\n");
618         else
619                 seq_printf(seq, "%u %sh\n", battery->alarm,
620                                 acpi_battery_units(battery));
621       end:
622         if (result)
623                 seq_printf(seq, "ERROR: Unable to read battery alarm\n");
624         return result;
625 }
626
627 static ssize_t acpi_battery_write_alarm(struct file *file,
628                                         const char __user * buffer,
629                                         size_t count, loff_t * ppos)
630 {
631         int result = 0;
632         char alarm_string[12] = { '\0' };
633         struct seq_file *m = file->private_data;
634         struct acpi_battery *battery = m->private;
635
636         if (!battery || (count > sizeof(alarm_string) - 1))
637                 return -EINVAL;
638         if (!acpi_battery_present(battery)) {
639                 result = -ENODEV;
640                 goto end;
641         }
642         if (copy_from_user(alarm_string, buffer, count)) {
643                 result = -EFAULT;
644                 goto end;
645         }
646         alarm_string[count] = '\0';
647         battery->alarm = simple_strtol(alarm_string, NULL, 0);
648         result = acpi_battery_set_alarm(battery);
649       end:
650         if (!result)
651                 return count;
652         return result;
653 }
654
655 typedef int(*print_func)(struct seq_file *seq, int result);
656
657 static print_func acpi_print_funcs[ACPI_BATTERY_NUMFILES] = {
658         acpi_battery_print_info,
659         acpi_battery_print_state,
660         acpi_battery_print_alarm,
661 };
662
663 static int acpi_battery_read(int fid, struct seq_file *seq)
664 {
665         struct acpi_battery *battery = seq->private;
666         int result = acpi_battery_update(battery);
667         return acpi_print_funcs[fid](seq, result);
668 }
669
670 #define DECLARE_FILE_FUNCTIONS(_name) \
671 static int acpi_battery_read_##_name(struct seq_file *seq, void *offset) \
672 { \
673         return acpi_battery_read(_name##_tag, seq); \
674 } \
675 static int acpi_battery_##_name##_open_fs(struct inode *inode, struct file *file) \
676 { \
677         return single_open(file, acpi_battery_read_##_name, PDE(inode)->data); \
678 }
679
680 DECLARE_FILE_FUNCTIONS(info);
681 DECLARE_FILE_FUNCTIONS(state);
682 DECLARE_FILE_FUNCTIONS(alarm);
683
684 #undef DECLARE_FILE_FUNCTIONS
685
686 #define FILE_DESCRIPTION_RO(_name) \
687         { \
688         .name = __stringify(_name), \
689         .mode = S_IRUGO, \
690         .ops = { \
691                 .open = acpi_battery_##_name##_open_fs, \
692                 .read = seq_read, \
693                 .llseek = seq_lseek, \
694                 .release = single_release, \
695                 .owner = THIS_MODULE, \
696                 }, \
697         }
698
699 #define FILE_DESCRIPTION_RW(_name) \
700         { \
701         .name = __stringify(_name), \
702         .mode = S_IFREG | S_IRUGO | S_IWUSR, \
703         .ops = { \
704                 .open = acpi_battery_##_name##_open_fs, \
705                 .read = seq_read, \
706                 .llseek = seq_lseek, \
707                 .write = acpi_battery_write_##_name, \
708                 .release = single_release, \
709                 .owner = THIS_MODULE, \
710                 }, \
711         }
712
713 static struct battery_file {
714         struct file_operations ops;
715         mode_t mode;
716         char *name;
717 } acpi_battery_file[] = {
718         FILE_DESCRIPTION_RO(info),
719         FILE_DESCRIPTION_RO(state),
720         FILE_DESCRIPTION_RW(alarm),
721 };
722
723 #undef FILE_DESCRIPTION_RO
724 #undef FILE_DESCRIPTION_RW
725
726 static int acpi_battery_add_fs(struct acpi_device *device)
727 {
728         struct proc_dir_entry *entry = NULL;
729         int i;
730
731         if (!acpi_device_dir(device)) {
732                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
733                                                      acpi_battery_dir);
734                 if (!acpi_device_dir(device))
735                         return -ENODEV;
736                 acpi_device_dir(device)->owner = THIS_MODULE;
737         }
738
739         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i) {
740                 entry = create_proc_entry(acpi_battery_file[i].name,
741                                   acpi_battery_file[i].mode, acpi_device_dir(device));
742                 if (!entry)
743                         return -ENODEV;
744                 else {
745                         entry->proc_fops = &acpi_battery_file[i].ops;
746                         entry->data = acpi_driver_data(device);
747                         entry->owner = THIS_MODULE;
748                 }
749         }
750         return 0;
751 }
752
753 static void acpi_battery_remove_fs(struct acpi_device *device)
754 {
755         int i;
756         if (!acpi_device_dir(device))
757                 return;
758         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i)
759                 remove_proc_entry(acpi_battery_file[i].name,
760                                   acpi_device_dir(device));
761
762         remove_proc_entry(acpi_device_bid(device), acpi_battery_dir);
763         acpi_device_dir(device) = NULL;
764 }
765
766 #endif
767
768 /* --------------------------------------------------------------------------
769                                  Driver Interface
770    -------------------------------------------------------------------------- */
771
772 static void acpi_battery_notify(acpi_handle handle, u32 event, void *data)
773 {
774         struct acpi_battery *battery = data;
775         struct acpi_device *device;
776         if (!battery)
777                 return;
778         device = battery->device;
779         acpi_battery_update(battery);
780         acpi_bus_generate_proc_event(device, event,
781                                      acpi_battery_present(battery));
782         acpi_bus_generate_netlink_event(device->pnp.device_class,
783                                         device->dev.bus_id, event,
784                                         acpi_battery_present(battery));
785 #ifdef CONFIG_ACPI_SYSFS_POWER
786         /* acpi_batter_update could remove power_supply object */
787         if (battery->bat.dev)
788                 kobject_uevent(&battery->bat.dev->kobj, KOBJ_CHANGE);
789 #endif
790 }
791
792 static int acpi_battery_add(struct acpi_device *device)
793 {
794         int result = 0;
795         acpi_status status = 0;
796         struct acpi_battery *battery = NULL;
797         if (!device)
798                 return -EINVAL;
799         battery = kzalloc(sizeof(struct acpi_battery), GFP_KERNEL);
800         if (!battery)
801                 return -ENOMEM;
802         battery->device = device;
803         strcpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
804         strcpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
805         acpi_driver_data(device) = battery;
806         mutex_init(&battery->lock);
807         acpi_battery_update(battery);
808 #ifdef CONFIG_ACPI_PROCFS_POWER
809         result = acpi_battery_add_fs(device);
810         if (result)
811                 goto end;
812 #endif
813         status = acpi_install_notify_handler(device->handle,
814                                              ACPI_ALL_NOTIFY,
815                                              acpi_battery_notify, battery);
816         if (ACPI_FAILURE(status)) {
817                 ACPI_EXCEPTION((AE_INFO, status, "Installing notify handler"));
818                 result = -ENODEV;
819                 goto end;
820         }
821         printk(KERN_INFO PREFIX "%s Slot [%s] (battery %s)\n",
822                ACPI_BATTERY_DEVICE_NAME, acpi_device_bid(device),
823                device->status.battery_present ? "present" : "absent");
824       end:
825         if (result) {
826 #ifdef CONFIG_ACPI_PROCFS_POWER
827                 acpi_battery_remove_fs(device);
828 #endif
829                 kfree(battery);
830         }
831         return result;
832 }
833
834 static int acpi_battery_remove(struct acpi_device *device, int type)
835 {
836         acpi_status status = 0;
837         struct acpi_battery *battery = NULL;
838
839         if (!device || !acpi_driver_data(device))
840                 return -EINVAL;
841         battery = acpi_driver_data(device);
842         status = acpi_remove_notify_handler(device->handle,
843                                             ACPI_ALL_NOTIFY,
844                                             acpi_battery_notify);
845 #ifdef CONFIG_ACPI_PROCFS_POWER
846         acpi_battery_remove_fs(device);
847 #endif
848 #ifdef CONFIG_ACPI_SYSFS_POWER
849         sysfs_remove_battery(battery);
850 #endif
851         mutex_destroy(&battery->lock);
852         kfree(battery);
853         return 0;
854 }
855
856 /* this is needed to learn about changes made in suspended state */
857 static int acpi_battery_resume(struct acpi_device *device)
858 {
859         struct acpi_battery *battery;
860         if (!device)
861                 return -EINVAL;
862         battery = acpi_driver_data(device);
863         battery->update_time = 0;
864         acpi_battery_update(battery);
865         return 0;
866 }
867
868 static struct acpi_driver acpi_battery_driver = {
869         .name = "battery",
870         .class = ACPI_BATTERY_CLASS,
871         .ids = battery_device_ids,
872         .ops = {
873                 .add = acpi_battery_add,
874                 .resume = acpi_battery_resume,
875                 .remove = acpi_battery_remove,
876                 },
877 };
878
879 static int __init acpi_battery_init(void)
880 {
881         if (acpi_disabled)
882                 return -ENODEV;
883 #ifdef CONFIG_ACPI_PROCFS_POWER
884         acpi_battery_dir = acpi_lock_battery_dir();
885         if (!acpi_battery_dir)
886                 return -ENODEV;
887 #endif
888         if (acpi_bus_register_driver(&acpi_battery_driver) < 0) {
889 #ifdef CONFIG_ACPI_PROCFS_POWER
890                 acpi_unlock_battery_dir(acpi_battery_dir);
891 #endif
892                 return -ENODEV;
893         }
894         return 0;
895 }
896
897 static void __exit acpi_battery_exit(void)
898 {
899         acpi_bus_unregister_driver(&acpi_battery_driver);
900 #ifdef CONFIG_ACPI_PROCFS_POWER
901         acpi_unlock_battery_dir(acpi_battery_dir);
902 #endif
903 }
904
905 module_init(acpi_battery_init);
906 module_exit(acpi_battery_exit);