ACPI: battery: fix CONFIG_ACPI_PROCFS_POWER=n build warning
[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 #include <linux/async.h>
34
35 #ifdef CONFIG_ACPI_PROCFS_POWER
36 #include <linux/proc_fs.h>
37 #include <linux/seq_file.h>
38 #include <asm/uaccess.h>
39 #endif
40
41 #include <acpi/acpi_bus.h>
42 #include <acpi/acpi_drivers.h>
43
44 #ifdef CONFIG_ACPI_SYSFS_POWER
45 #include <linux/power_supply.h>
46 #endif
47
48 #define ACPI_BATTERY_VALUE_UNKNOWN 0xFFFFFFFF
49
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 rate_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_is_charged(struct acpi_battery *battery)
143 {
144         /* either charging or discharging */
145         if (battery->state != 0)
146                 return 0;
147
148         /* battery not reporting charge */
149         if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN ||
150             battery->capacity_now == 0)
151                 return 0;
152
153         /* good batteries update full_charge as the batteries degrade */
154         if (battery->full_charge_capacity == battery->capacity_now)
155                 return 1;
156
157         /* fallback to using design values for broken batteries */
158         if (battery->design_capacity == battery->capacity_now)
159                 return 1;
160
161         /* we don't do any sort of metric based on percentages */
162         return 0;
163 }
164
165 static int acpi_battery_get_property(struct power_supply *psy,
166                                      enum power_supply_property psp,
167                                      union power_supply_propval *val)
168 {
169         struct acpi_battery *battery = to_acpi_battery(psy);
170
171         if (acpi_battery_present(battery)) {
172                 /* run battery update only if it is present */
173                 acpi_battery_get_state(battery);
174         } else if (psp != POWER_SUPPLY_PROP_PRESENT)
175                 return -ENODEV;
176         switch (psp) {
177         case POWER_SUPPLY_PROP_STATUS:
178                 if (battery->state & 0x01)
179                         val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
180                 else if (battery->state & 0x02)
181                         val->intval = POWER_SUPPLY_STATUS_CHARGING;
182                 else if (acpi_battery_is_charged(battery))
183                         val->intval = POWER_SUPPLY_STATUS_FULL;
184                 else
185                         val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
186                 break;
187         case POWER_SUPPLY_PROP_PRESENT:
188                 val->intval = acpi_battery_present(battery);
189                 break;
190         case POWER_SUPPLY_PROP_TECHNOLOGY:
191                 val->intval = acpi_battery_technology(battery);
192                 break;
193         case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
194                 val->intval = battery->design_voltage * 1000;
195                 break;
196         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
197                 val->intval = battery->voltage_now * 1000;
198                 break;
199         case POWER_SUPPLY_PROP_CURRENT_NOW:
200         case POWER_SUPPLY_PROP_POWER_NOW:
201                 val->intval = battery->rate_now * 1000;
202                 break;
203         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
204         case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
205                 val->intval = battery->design_capacity * 1000;
206                 break;
207         case POWER_SUPPLY_PROP_CHARGE_FULL:
208         case POWER_SUPPLY_PROP_ENERGY_FULL:
209                 val->intval = battery->full_charge_capacity * 1000;
210                 break;
211         case POWER_SUPPLY_PROP_CHARGE_NOW:
212         case POWER_SUPPLY_PROP_ENERGY_NOW:
213                 val->intval = battery->capacity_now * 1000;
214                 break;
215         case POWER_SUPPLY_PROP_MODEL_NAME:
216                 val->strval = battery->model_number;
217                 break;
218         case POWER_SUPPLY_PROP_MANUFACTURER:
219                 val->strval = battery->oem_info;
220                 break;
221         case POWER_SUPPLY_PROP_SERIAL_NUMBER:
222                 val->strval = battery->serial_number;
223                 break;
224         default:
225                 return -EINVAL;
226         }
227         return 0;
228 }
229
230 static enum power_supply_property charge_battery_props[] = {
231         POWER_SUPPLY_PROP_STATUS,
232         POWER_SUPPLY_PROP_PRESENT,
233         POWER_SUPPLY_PROP_TECHNOLOGY,
234         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
235         POWER_SUPPLY_PROP_VOLTAGE_NOW,
236         POWER_SUPPLY_PROP_CURRENT_NOW,
237         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
238         POWER_SUPPLY_PROP_CHARGE_FULL,
239         POWER_SUPPLY_PROP_CHARGE_NOW,
240         POWER_SUPPLY_PROP_MODEL_NAME,
241         POWER_SUPPLY_PROP_MANUFACTURER,
242         POWER_SUPPLY_PROP_SERIAL_NUMBER,
243 };
244
245 static enum power_supply_property energy_battery_props[] = {
246         POWER_SUPPLY_PROP_STATUS,
247         POWER_SUPPLY_PROP_PRESENT,
248         POWER_SUPPLY_PROP_TECHNOLOGY,
249         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
250         POWER_SUPPLY_PROP_VOLTAGE_NOW,
251         POWER_SUPPLY_PROP_CURRENT_NOW,
252         POWER_SUPPLY_PROP_POWER_NOW,
253         POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
254         POWER_SUPPLY_PROP_ENERGY_FULL,
255         POWER_SUPPLY_PROP_ENERGY_NOW,
256         POWER_SUPPLY_PROP_MODEL_NAME,
257         POWER_SUPPLY_PROP_MANUFACTURER,
258         POWER_SUPPLY_PROP_SERIAL_NUMBER,
259 };
260 #endif
261
262 #ifdef CONFIG_ACPI_PROCFS_POWER
263 inline char *acpi_battery_units(struct acpi_battery *battery)
264 {
265         return (battery->power_unit)?"mA":"mW";
266 }
267 #endif
268
269 /* --------------------------------------------------------------------------
270                                Battery Management
271    -------------------------------------------------------------------------- */
272 struct acpi_offsets {
273         size_t offset;          /* offset inside struct acpi_sbs_battery */
274         u8 mode;                /* int or string? */
275 };
276
277 static struct acpi_offsets state_offsets[] = {
278         {offsetof(struct acpi_battery, state), 0},
279         {offsetof(struct acpi_battery, rate_now), 0},
280         {offsetof(struct acpi_battery, capacity_now), 0},
281         {offsetof(struct acpi_battery, voltage_now), 0},
282 };
283
284 static struct acpi_offsets info_offsets[] = {
285         {offsetof(struct acpi_battery, power_unit), 0},
286         {offsetof(struct acpi_battery, design_capacity), 0},
287         {offsetof(struct acpi_battery, full_charge_capacity), 0},
288         {offsetof(struct acpi_battery, technology), 0},
289         {offsetof(struct acpi_battery, design_voltage), 0},
290         {offsetof(struct acpi_battery, design_capacity_warning), 0},
291         {offsetof(struct acpi_battery, design_capacity_low), 0},
292         {offsetof(struct acpi_battery, capacity_granularity_1), 0},
293         {offsetof(struct acpi_battery, capacity_granularity_2), 0},
294         {offsetof(struct acpi_battery, model_number), 1},
295         {offsetof(struct acpi_battery, serial_number), 1},
296         {offsetof(struct acpi_battery, type), 1},
297         {offsetof(struct acpi_battery, oem_info), 1},
298 };
299
300 static int extract_package(struct acpi_battery *battery,
301                            union acpi_object *package,
302                            struct acpi_offsets *offsets, int num)
303 {
304         int i;
305         union acpi_object *element;
306         if (package->type != ACPI_TYPE_PACKAGE)
307                 return -EFAULT;
308         for (i = 0; i < num; ++i) {
309                 if (package->package.count <= i)
310                         return -EFAULT;
311                 element = &package->package.elements[i];
312                 if (offsets[i].mode) {
313                         u8 *ptr = (u8 *)battery + offsets[i].offset;
314                         if (element->type == ACPI_TYPE_STRING ||
315                             element->type == ACPI_TYPE_BUFFER)
316                                 strncpy(ptr, element->string.pointer, 32);
317                         else if (element->type == ACPI_TYPE_INTEGER) {
318                                 strncpy(ptr, (u8 *)&element->integer.value,
319                                         sizeof(acpi_integer));
320                                 ptr[sizeof(acpi_integer)] = 0;
321                         } else
322                                 *ptr = 0; /* don't have value */
323                 } else {
324                         int *x = (int *)((u8 *)battery + offsets[i].offset);
325                         *x = (element->type == ACPI_TYPE_INTEGER) ?
326                                 element->integer.value : -1;
327                 }
328         }
329         return 0;
330 }
331
332 static int acpi_battery_get_status(struct acpi_battery *battery)
333 {
334         if (acpi_bus_get_status(battery->device)) {
335                 ACPI_EXCEPTION((AE_INFO, AE_ERROR, "Evaluating _STA"));
336                 return -ENODEV;
337         }
338         return 0;
339 }
340
341 static int acpi_battery_get_info(struct acpi_battery *battery)
342 {
343         int result = -EFAULT;
344         acpi_status status = 0;
345         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
346
347         if (!acpi_battery_present(battery))
348                 return 0;
349         mutex_lock(&battery->lock);
350         status = acpi_evaluate_object(battery->device->handle, "_BIF",
351                                       NULL, &buffer);
352         mutex_unlock(&battery->lock);
353
354         if (ACPI_FAILURE(status)) {
355                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BIF"));
356                 return -ENODEV;
357         }
358
359         result = extract_package(battery, buffer.pointer,
360                                  info_offsets, ARRAY_SIZE(info_offsets));
361         kfree(buffer.pointer);
362         return result;
363 }
364
365 static int acpi_battery_get_state(struct acpi_battery *battery)
366 {
367         int result = 0;
368         acpi_status status = 0;
369         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
370
371         if (!acpi_battery_present(battery))
372                 return 0;
373
374         if (battery->update_time &&
375             time_before(jiffies, battery->update_time +
376                         msecs_to_jiffies(cache_time)))
377                 return 0;
378
379         mutex_lock(&battery->lock);
380         status = acpi_evaluate_object(battery->device->handle, "_BST",
381                                       NULL, &buffer);
382         mutex_unlock(&battery->lock);
383
384         if (ACPI_FAILURE(status)) {
385                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BST"));
386                 return -ENODEV;
387         }
388
389         result = extract_package(battery, buffer.pointer,
390                                  state_offsets, ARRAY_SIZE(state_offsets));
391         battery->update_time = jiffies;
392         kfree(buffer.pointer);
393         return result;
394 }
395
396 static int acpi_battery_set_alarm(struct acpi_battery *battery)
397 {
398         acpi_status status = 0;
399         union acpi_object arg0 = { .type = ACPI_TYPE_INTEGER };
400         struct acpi_object_list arg_list = { 1, &arg0 };
401
402         if (!acpi_battery_present(battery)|| !battery->alarm_present)
403                 return -ENODEV;
404
405         arg0.integer.value = battery->alarm;
406
407         mutex_lock(&battery->lock);
408         status = acpi_evaluate_object(battery->device->handle, "_BTP",
409                                  &arg_list, NULL);
410         mutex_unlock(&battery->lock);
411
412         if (ACPI_FAILURE(status))
413                 return -ENODEV;
414
415         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Alarm set to %d\n", battery->alarm));
416         return 0;
417 }
418
419 static int acpi_battery_init_alarm(struct acpi_battery *battery)
420 {
421         acpi_status status = AE_OK;
422         acpi_handle handle = NULL;
423
424         /* See if alarms are supported, and if so, set default */
425         status = acpi_get_handle(battery->device->handle, "_BTP", &handle);
426         if (ACPI_FAILURE(status)) {
427                 battery->alarm_present = 0;
428                 return 0;
429         }
430         battery->alarm_present = 1;
431         if (!battery->alarm)
432                 battery->alarm = battery->design_capacity_warning;
433         return acpi_battery_set_alarm(battery);
434 }
435
436 #ifdef CONFIG_ACPI_SYSFS_POWER
437 static ssize_t acpi_battery_alarm_show(struct device *dev,
438                                         struct device_attribute *attr,
439                                         char *buf)
440 {
441         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
442         return sprintf(buf, "%d\n", battery->alarm * 1000);
443 }
444
445 static ssize_t acpi_battery_alarm_store(struct device *dev,
446                                         struct device_attribute *attr,
447                                         const char *buf, size_t count)
448 {
449         unsigned long x;
450         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
451         if (sscanf(buf, "%ld\n", &x) == 1)
452                 battery->alarm = x/1000;
453         if (acpi_battery_present(battery))
454                 acpi_battery_set_alarm(battery);
455         return count;
456 }
457
458 static struct device_attribute alarm_attr = {
459         .attr = {.name = "alarm", .mode = 0644},
460         .show = acpi_battery_alarm_show,
461         .store = acpi_battery_alarm_store,
462 };
463
464 static int sysfs_add_battery(struct acpi_battery *battery)
465 {
466         int result;
467
468         if (battery->power_unit) {
469                 battery->bat.properties = charge_battery_props;
470                 battery->bat.num_properties =
471                         ARRAY_SIZE(charge_battery_props);
472         } else {
473                 battery->bat.properties = energy_battery_props;
474                 battery->bat.num_properties =
475                         ARRAY_SIZE(energy_battery_props);
476         }
477
478         battery->bat.name = acpi_device_bid(battery->device);
479         battery->bat.type = POWER_SUPPLY_TYPE_BATTERY;
480         battery->bat.get_property = acpi_battery_get_property;
481
482         result = power_supply_register(&battery->device->dev, &battery->bat);
483         if (result)
484                 return result;
485         return device_create_file(battery->bat.dev, &alarm_attr);
486 }
487
488 static void sysfs_remove_battery(struct acpi_battery *battery)
489 {
490         if (!battery->bat.dev)
491                 return;
492         device_remove_file(battery->bat.dev, &alarm_attr);
493         power_supply_unregister(&battery->bat);
494         battery->bat.dev = NULL;
495 }
496 #endif
497
498 static int acpi_battery_update(struct acpi_battery *battery)
499 {
500         int result, old_present = acpi_battery_present(battery);
501         result = acpi_battery_get_status(battery);
502         if (result)
503                 return result;
504 #ifdef CONFIG_ACPI_SYSFS_POWER
505         if (!acpi_battery_present(battery)) {
506                 sysfs_remove_battery(battery);
507                 battery->update_time = 0;
508                 return 0;
509         }
510 #endif
511         if (!battery->update_time ||
512             old_present != acpi_battery_present(battery)) {
513                 result = acpi_battery_get_info(battery);
514                 if (result)
515                         return result;
516                 acpi_battery_init_alarm(battery);
517         }
518 #ifdef CONFIG_ACPI_SYSFS_POWER
519         if (!battery->bat.dev)
520                 sysfs_add_battery(battery);
521 #endif
522         return acpi_battery_get_state(battery);
523 }
524
525 /* --------------------------------------------------------------------------
526                               FS Interface (/proc)
527    -------------------------------------------------------------------------- */
528
529 #ifdef CONFIG_ACPI_PROCFS_POWER
530 static struct proc_dir_entry *acpi_battery_dir;
531
532 static int acpi_battery_print_info(struct seq_file *seq, int result)
533 {
534         struct acpi_battery *battery = seq->private;
535
536         if (result)
537                 goto end;
538
539         seq_printf(seq, "present:                 %s\n",
540                    acpi_battery_present(battery)?"yes":"no");
541         if (!acpi_battery_present(battery))
542                 goto end;
543         if (battery->design_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
544                 seq_printf(seq, "design capacity:         unknown\n");
545         else
546                 seq_printf(seq, "design capacity:         %d %sh\n",
547                            battery->design_capacity,
548                            acpi_battery_units(battery));
549
550         if (battery->full_charge_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
551                 seq_printf(seq, "last full capacity:      unknown\n");
552         else
553                 seq_printf(seq, "last full capacity:      %d %sh\n",
554                            battery->full_charge_capacity,
555                            acpi_battery_units(battery));
556
557         seq_printf(seq, "battery technology:      %srechargeable\n",
558                    (!battery->technology)?"non-":"");
559
560         if (battery->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
561                 seq_printf(seq, "design voltage:          unknown\n");
562         else
563                 seq_printf(seq, "design voltage:          %d mV\n",
564                            battery->design_voltage);
565         seq_printf(seq, "design capacity warning: %d %sh\n",
566                    battery->design_capacity_warning,
567                    acpi_battery_units(battery));
568         seq_printf(seq, "design capacity low:     %d %sh\n",
569                    battery->design_capacity_low,
570                    acpi_battery_units(battery));
571         seq_printf(seq, "capacity granularity 1:  %d %sh\n",
572                    battery->capacity_granularity_1,
573                    acpi_battery_units(battery));
574         seq_printf(seq, "capacity granularity 2:  %d %sh\n",
575                    battery->capacity_granularity_2,
576                    acpi_battery_units(battery));
577         seq_printf(seq, "model number:            %s\n", battery->model_number);
578         seq_printf(seq, "serial number:           %s\n", battery->serial_number);
579         seq_printf(seq, "battery type:            %s\n", battery->type);
580         seq_printf(seq, "OEM info:                %s\n", battery->oem_info);
581       end:
582         if (result)
583                 seq_printf(seq, "ERROR: Unable to read battery info\n");
584         return result;
585 }
586
587 static int acpi_battery_print_state(struct seq_file *seq, int result)
588 {
589         struct acpi_battery *battery = seq->private;
590
591         if (result)
592                 goto end;
593
594         seq_printf(seq, "present:                 %s\n",
595                    acpi_battery_present(battery)?"yes":"no");
596         if (!acpi_battery_present(battery))
597                 goto end;
598
599         seq_printf(seq, "capacity state:          %s\n",
600                         (battery->state & 0x04)?"critical":"ok");
601         if ((battery->state & 0x01) && (battery->state & 0x02))
602                 seq_printf(seq,
603                            "charging state:          charging/discharging\n");
604         else if (battery->state & 0x01)
605                 seq_printf(seq, "charging state:          discharging\n");
606         else if (battery->state & 0x02)
607                 seq_printf(seq, "charging state:          charging\n");
608         else
609                 seq_printf(seq, "charging state:          charged\n");
610
611         if (battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN)
612                 seq_printf(seq, "present rate:            unknown\n");
613         else
614                 seq_printf(seq, "present rate:            %d %s\n",
615                            battery->rate_now, acpi_battery_units(battery));
616
617         if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN)
618                 seq_printf(seq, "remaining capacity:      unknown\n");
619         else
620                 seq_printf(seq, "remaining capacity:      %d %sh\n",
621                            battery->capacity_now, acpi_battery_units(battery));
622         if (battery->voltage_now == ACPI_BATTERY_VALUE_UNKNOWN)
623                 seq_printf(seq, "present voltage:         unknown\n");
624         else
625                 seq_printf(seq, "present voltage:         %d mV\n",
626                            battery->voltage_now);
627       end:
628         if (result)
629                 seq_printf(seq, "ERROR: Unable to read battery state\n");
630
631         return result;
632 }
633
634 static int acpi_battery_print_alarm(struct seq_file *seq, int result)
635 {
636         struct acpi_battery *battery = seq->private;
637
638         if (result)
639                 goto end;
640
641         if (!acpi_battery_present(battery)) {
642                 seq_printf(seq, "present:                 no\n");
643                 goto end;
644         }
645         seq_printf(seq, "alarm:                   ");
646         if (!battery->alarm)
647                 seq_printf(seq, "unsupported\n");
648         else
649                 seq_printf(seq, "%u %sh\n", battery->alarm,
650                                 acpi_battery_units(battery));
651       end:
652         if (result)
653                 seq_printf(seq, "ERROR: Unable to read battery alarm\n");
654         return result;
655 }
656
657 static ssize_t acpi_battery_write_alarm(struct file *file,
658                                         const char __user * buffer,
659                                         size_t count, loff_t * ppos)
660 {
661         int result = 0;
662         char alarm_string[12] = { '\0' };
663         struct seq_file *m = file->private_data;
664         struct acpi_battery *battery = m->private;
665
666         if (!battery || (count > sizeof(alarm_string) - 1))
667                 return -EINVAL;
668         if (!acpi_battery_present(battery)) {
669                 result = -ENODEV;
670                 goto end;
671         }
672         if (copy_from_user(alarm_string, buffer, count)) {
673                 result = -EFAULT;
674                 goto end;
675         }
676         alarm_string[count] = '\0';
677         battery->alarm = simple_strtol(alarm_string, NULL, 0);
678         result = acpi_battery_set_alarm(battery);
679       end:
680         if (!result)
681                 return count;
682         return result;
683 }
684
685 typedef int(*print_func)(struct seq_file *seq, int result);
686
687 static print_func acpi_print_funcs[ACPI_BATTERY_NUMFILES] = {
688         acpi_battery_print_info,
689         acpi_battery_print_state,
690         acpi_battery_print_alarm,
691 };
692
693 static int acpi_battery_read(int fid, struct seq_file *seq)
694 {
695         struct acpi_battery *battery = seq->private;
696         int result = acpi_battery_update(battery);
697         return acpi_print_funcs[fid](seq, result);
698 }
699
700 #define DECLARE_FILE_FUNCTIONS(_name) \
701 static int acpi_battery_read_##_name(struct seq_file *seq, void *offset) \
702 { \
703         return acpi_battery_read(_name##_tag, seq); \
704 } \
705 static int acpi_battery_##_name##_open_fs(struct inode *inode, struct file *file) \
706 { \
707         return single_open(file, acpi_battery_read_##_name, PDE(inode)->data); \
708 }
709
710 DECLARE_FILE_FUNCTIONS(info);
711 DECLARE_FILE_FUNCTIONS(state);
712 DECLARE_FILE_FUNCTIONS(alarm);
713
714 #undef DECLARE_FILE_FUNCTIONS
715
716 #define FILE_DESCRIPTION_RO(_name) \
717         { \
718         .name = __stringify(_name), \
719         .mode = S_IRUGO, \
720         .ops = { \
721                 .open = acpi_battery_##_name##_open_fs, \
722                 .read = seq_read, \
723                 .llseek = seq_lseek, \
724                 .release = single_release, \
725                 .owner = THIS_MODULE, \
726                 }, \
727         }
728
729 #define FILE_DESCRIPTION_RW(_name) \
730         { \
731         .name = __stringify(_name), \
732         .mode = S_IFREG | S_IRUGO | S_IWUSR, \
733         .ops = { \
734                 .open = acpi_battery_##_name##_open_fs, \
735                 .read = seq_read, \
736                 .llseek = seq_lseek, \
737                 .write = acpi_battery_write_##_name, \
738                 .release = single_release, \
739                 .owner = THIS_MODULE, \
740                 }, \
741         }
742
743 static struct battery_file {
744         struct file_operations ops;
745         mode_t mode;
746         const char *name;
747 } acpi_battery_file[] = {
748         FILE_DESCRIPTION_RO(info),
749         FILE_DESCRIPTION_RO(state),
750         FILE_DESCRIPTION_RW(alarm),
751 };
752
753 #undef FILE_DESCRIPTION_RO
754 #undef FILE_DESCRIPTION_RW
755
756 static int acpi_battery_add_fs(struct acpi_device *device)
757 {
758         struct proc_dir_entry *entry = NULL;
759         int i;
760
761         if (!acpi_device_dir(device)) {
762                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
763                                                      acpi_battery_dir);
764                 if (!acpi_device_dir(device))
765                         return -ENODEV;
766         }
767
768         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i) {
769                 entry = proc_create_data(acpi_battery_file[i].name,
770                                          acpi_battery_file[i].mode,
771                                          acpi_device_dir(device),
772                                          &acpi_battery_file[i].ops,
773                                          acpi_driver_data(device));
774                 if (!entry)
775                         return -ENODEV;
776         }
777         return 0;
778 }
779
780 static void acpi_battery_remove_fs(struct acpi_device *device)
781 {
782         int i;
783         if (!acpi_device_dir(device))
784                 return;
785         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i)
786                 remove_proc_entry(acpi_battery_file[i].name,
787                                   acpi_device_dir(device));
788
789         remove_proc_entry(acpi_device_bid(device), acpi_battery_dir);
790         acpi_device_dir(device) = NULL;
791 }
792
793 #endif
794
795 /* --------------------------------------------------------------------------
796                                  Driver Interface
797    -------------------------------------------------------------------------- */
798
799 static void acpi_battery_notify(struct acpi_device *device, u32 event)
800 {
801         struct acpi_battery *battery = acpi_driver_data(device);
802
803         if (!battery)
804                 return;
805         acpi_battery_update(battery);
806         acpi_bus_generate_proc_event(device, event,
807                                      acpi_battery_present(battery));
808         acpi_bus_generate_netlink_event(device->pnp.device_class,
809                                         dev_name(&device->dev), event,
810                                         acpi_battery_present(battery));
811 #ifdef CONFIG_ACPI_SYSFS_POWER
812         /* acpi_batter_update could remove power_supply object */
813         if (battery->bat.dev)
814                 kobject_uevent(&battery->bat.dev->kobj, KOBJ_CHANGE);
815 #endif
816 }
817
818 static int acpi_battery_add(struct acpi_device *device)
819 {
820         int result = 0;
821         struct acpi_battery *battery = NULL;
822         if (!device)
823                 return -EINVAL;
824         battery = kzalloc(sizeof(struct acpi_battery), GFP_KERNEL);
825         if (!battery)
826                 return -ENOMEM;
827         battery->device = device;
828         strcpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
829         strcpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
830         device->driver_data = battery;
831         mutex_init(&battery->lock);
832         acpi_battery_update(battery);
833 #ifdef CONFIG_ACPI_PROCFS_POWER
834         result = acpi_battery_add_fs(device);
835 #endif
836         if (!result) {
837                 printk(KERN_INFO PREFIX "%s Slot [%s] (battery %s)\n",
838                         ACPI_BATTERY_DEVICE_NAME, acpi_device_bid(device),
839                         device->status.battery_present ? "present" : "absent");
840         } else {
841 #ifdef CONFIG_ACPI_PROCFS_POWER
842                 acpi_battery_remove_fs(device);
843 #endif
844                 kfree(battery);
845         }
846         return result;
847 }
848
849 static int acpi_battery_remove(struct acpi_device *device, int type)
850 {
851         struct acpi_battery *battery = NULL;
852
853         if (!device || !acpi_driver_data(device))
854                 return -EINVAL;
855         battery = acpi_driver_data(device);
856 #ifdef CONFIG_ACPI_PROCFS_POWER
857         acpi_battery_remove_fs(device);
858 #endif
859 #ifdef CONFIG_ACPI_SYSFS_POWER
860         sysfs_remove_battery(battery);
861 #endif
862         mutex_destroy(&battery->lock);
863         kfree(battery);
864         return 0;
865 }
866
867 /* this is needed to learn about changes made in suspended state */
868 static int acpi_battery_resume(struct acpi_device *device)
869 {
870         struct acpi_battery *battery;
871         if (!device)
872                 return -EINVAL;
873         battery = acpi_driver_data(device);
874         battery->update_time = 0;
875         acpi_battery_update(battery);
876         return 0;
877 }
878
879 static struct acpi_driver acpi_battery_driver = {
880         .name = "battery",
881         .class = ACPI_BATTERY_CLASS,
882         .ids = battery_device_ids,
883         .flags = ACPI_DRIVER_ALL_NOTIFY_EVENTS,
884         .ops = {
885                 .add = acpi_battery_add,
886                 .resume = acpi_battery_resume,
887                 .remove = acpi_battery_remove,
888                 .notify = acpi_battery_notify,
889                 },
890 };
891
892 static void __init acpi_battery_init_async(void *unused, async_cookie_t cookie)
893 {
894         if (acpi_disabled)
895                 return;
896 #ifdef CONFIG_ACPI_PROCFS_POWER
897         acpi_battery_dir = acpi_lock_battery_dir();
898         if (!acpi_battery_dir)
899                 return;
900 #endif
901         if (acpi_bus_register_driver(&acpi_battery_driver) < 0) {
902 #ifdef CONFIG_ACPI_PROCFS_POWER
903                 acpi_unlock_battery_dir(acpi_battery_dir);
904 #endif
905                 return;
906         }
907         return;
908 }
909
910 static int __init acpi_battery_init(void)
911 {
912         async_schedule(acpi_battery_init_async, NULL);
913         return 0;
914 }
915
916 static void __exit acpi_battery_exit(void)
917 {
918         acpi_bus_unregister_driver(&acpi_battery_driver);
919 #ifdef CONFIG_ACPI_PROCFS_POWER
920         acpi_unlock_battery_dir(acpi_battery_dir);
921 #endif
922 }
923
924 module_init(acpi_battery_init);
925 module_exit(acpi_battery_exit);