ACPI: constify VFTs (1/2)
[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_CLASS              "battery"
50 #define ACPI_BATTERY_DEVICE_NAME        "Battery"
51 #define ACPI_BATTERY_NOTIFY_STATUS      0x80
52 #define ACPI_BATTERY_NOTIFY_INFO        0x81
53
54 #define _COMPONENT              ACPI_BATTERY_COMPONENT
55
56 ACPI_MODULE_NAME("battery");
57
58 MODULE_AUTHOR("Paul Diefenbaugh");
59 MODULE_AUTHOR("Alexey Starikovskiy <astarikovskiy@suse.de>");
60 MODULE_DESCRIPTION("ACPI Battery Driver");
61 MODULE_LICENSE("GPL");
62
63 static unsigned int cache_time = 1000;
64 module_param(cache_time, uint, 0644);
65 MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
66
67 #ifdef CONFIG_ACPI_PROCFS_POWER
68 extern struct proc_dir_entry *acpi_lock_battery_dir(void);
69 extern void *acpi_unlock_battery_dir(struct proc_dir_entry *acpi_battery_dir);
70
71 enum acpi_battery_files {
72         info_tag = 0,
73         state_tag,
74         alarm_tag,
75         ACPI_BATTERY_NUMFILES,
76 };
77
78 #endif
79
80 static const struct acpi_device_id battery_device_ids[] = {
81         {"PNP0C0A", 0},
82         {"", 0},
83 };
84
85 MODULE_DEVICE_TABLE(acpi, battery_device_ids);
86
87
88 struct acpi_battery {
89         struct mutex lock;
90 #ifdef CONFIG_ACPI_SYSFS_POWER
91         struct power_supply bat;
92 #endif
93         struct acpi_device *device;
94         unsigned long update_time;
95         int current_now;
96         int capacity_now;
97         int voltage_now;
98         int design_capacity;
99         int full_charge_capacity;
100         int technology;
101         int design_voltage;
102         int design_capacity_warning;
103         int design_capacity_low;
104         int capacity_granularity_1;
105         int capacity_granularity_2;
106         int alarm;
107         char model_number[32];
108         char serial_number[32];
109         char type[32];
110         char oem_info[32];
111         int state;
112         int power_unit;
113         u8 alarm_present;
114 };
115
116 #define to_acpi_battery(x) container_of(x, struct acpi_battery, bat);
117
118 inline int acpi_battery_present(struct acpi_battery *battery)
119 {
120         return battery->device->status.battery_present;
121 }
122
123 #ifdef CONFIG_ACPI_SYSFS_POWER
124 static int acpi_battery_technology(struct acpi_battery *battery)
125 {
126         if (!strcasecmp("NiCd", battery->type))
127                 return POWER_SUPPLY_TECHNOLOGY_NiCd;
128         if (!strcasecmp("NiMH", battery->type))
129                 return POWER_SUPPLY_TECHNOLOGY_NiMH;
130         if (!strcasecmp("LION", battery->type))
131                 return POWER_SUPPLY_TECHNOLOGY_LION;
132         if (!strncasecmp("LI-ION", battery->type, 6))
133                 return POWER_SUPPLY_TECHNOLOGY_LION;
134         if (!strcasecmp("LiP", battery->type))
135                 return POWER_SUPPLY_TECHNOLOGY_LIPO;
136         return POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
137 }
138
139 static int acpi_battery_get_state(struct acpi_battery *battery);
140
141 static int acpi_battery_is_charged(struct acpi_battery *battery)
142 {
143         /* either charging or discharging */
144         if (battery->state != 0)
145                 return 0;
146
147         /* battery not reporting charge */
148         if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN ||
149             battery->capacity_now == 0)
150                 return 0;
151
152         /* good batteries update full_charge as the batteries degrade */
153         if (battery->full_charge_capacity == battery->capacity_now)
154                 return 1;
155
156         /* fallback to using design values for broken batteries */
157         if (battery->design_capacity == battery->capacity_now)
158                 return 1;
159
160         /* we don't do any sort of metric based on percentages */
161         return 0;
162 }
163
164 static int acpi_battery_get_property(struct power_supply *psy,
165                                      enum power_supply_property psp,
166                                      union power_supply_propval *val)
167 {
168         struct acpi_battery *battery = to_acpi_battery(psy);
169
170         if (acpi_battery_present(battery)) {
171                 /* run battery update only if it is present */
172                 acpi_battery_get_state(battery);
173         } else if (psp != POWER_SUPPLY_PROP_PRESENT)
174                 return -ENODEV;
175         switch (psp) {
176         case POWER_SUPPLY_PROP_STATUS:
177                 if (battery->state & 0x01)
178                         val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
179                 else if (battery->state & 0x02)
180                         val->intval = POWER_SUPPLY_STATUS_CHARGING;
181                 else if (acpi_battery_is_charged(battery))
182                         val->intval = POWER_SUPPLY_STATUS_FULL;
183                 else
184                         val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
185                 break;
186         case POWER_SUPPLY_PROP_PRESENT:
187                 val->intval = acpi_battery_present(battery);
188                 break;
189         case POWER_SUPPLY_PROP_TECHNOLOGY:
190                 val->intval = acpi_battery_technology(battery);
191                 break;
192         case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
193                 val->intval = battery->design_voltage * 1000;
194                 break;
195         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
196                 val->intval = battery->voltage_now * 1000;
197                 break;
198         case POWER_SUPPLY_PROP_CURRENT_NOW:
199                 val->intval = battery->current_now * 1000;
200                 break;
201         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
202         case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
203                 val->intval = battery->design_capacity * 1000;
204                 break;
205         case POWER_SUPPLY_PROP_CHARGE_FULL:
206         case POWER_SUPPLY_PROP_ENERGY_FULL:
207                 val->intval = battery->full_charge_capacity * 1000;
208                 break;
209         case POWER_SUPPLY_PROP_CHARGE_NOW:
210         case POWER_SUPPLY_PROP_ENERGY_NOW:
211                 val->intval = battery->capacity_now * 1000;
212                 break;
213         case POWER_SUPPLY_PROP_MODEL_NAME:
214                 val->strval = battery->model_number;
215                 break;
216         case POWER_SUPPLY_PROP_MANUFACTURER:
217                 val->strval = battery->oem_info;
218                 break;
219         case POWER_SUPPLY_PROP_SERIAL_NUMBER:
220                 val->strval = battery->serial_number;
221                 break;
222         default:
223                 return -EINVAL;
224         }
225         return 0;
226 }
227
228 static enum power_supply_property charge_battery_props[] = {
229         POWER_SUPPLY_PROP_STATUS,
230         POWER_SUPPLY_PROP_PRESENT,
231         POWER_SUPPLY_PROP_TECHNOLOGY,
232         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
233         POWER_SUPPLY_PROP_VOLTAGE_NOW,
234         POWER_SUPPLY_PROP_CURRENT_NOW,
235         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
236         POWER_SUPPLY_PROP_CHARGE_FULL,
237         POWER_SUPPLY_PROP_CHARGE_NOW,
238         POWER_SUPPLY_PROP_MODEL_NAME,
239         POWER_SUPPLY_PROP_MANUFACTURER,
240         POWER_SUPPLY_PROP_SERIAL_NUMBER,
241 };
242
243 static enum power_supply_property energy_battery_props[] = {
244         POWER_SUPPLY_PROP_STATUS,
245         POWER_SUPPLY_PROP_PRESENT,
246         POWER_SUPPLY_PROP_TECHNOLOGY,
247         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
248         POWER_SUPPLY_PROP_VOLTAGE_NOW,
249         POWER_SUPPLY_PROP_CURRENT_NOW,
250         POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
251         POWER_SUPPLY_PROP_ENERGY_FULL,
252         POWER_SUPPLY_PROP_ENERGY_NOW,
253         POWER_SUPPLY_PROP_MODEL_NAME,
254         POWER_SUPPLY_PROP_MANUFACTURER,
255         POWER_SUPPLY_PROP_SERIAL_NUMBER,
256 };
257 #endif
258
259 #ifdef CONFIG_ACPI_PROCFS_POWER
260 inline char *acpi_battery_units(struct acpi_battery *battery)
261 {
262         return (battery->power_unit)?"mA":"mW";
263 }
264 #endif
265
266 /* --------------------------------------------------------------------------
267                                Battery Management
268    -------------------------------------------------------------------------- */
269 struct acpi_offsets {
270         size_t offset;          /* offset inside struct acpi_sbs_battery */
271         u8 mode;                /* int or string? */
272 };
273
274 static struct acpi_offsets state_offsets[] = {
275         {offsetof(struct acpi_battery, state), 0},
276         {offsetof(struct acpi_battery, current_now), 0},
277         {offsetof(struct acpi_battery, capacity_now), 0},
278         {offsetof(struct acpi_battery, voltage_now), 0},
279 };
280
281 static struct acpi_offsets info_offsets[] = {
282         {offsetof(struct acpi_battery, power_unit), 0},
283         {offsetof(struct acpi_battery, design_capacity), 0},
284         {offsetof(struct acpi_battery, full_charge_capacity), 0},
285         {offsetof(struct acpi_battery, technology), 0},
286         {offsetof(struct acpi_battery, design_voltage), 0},
287         {offsetof(struct acpi_battery, design_capacity_warning), 0},
288         {offsetof(struct acpi_battery, design_capacity_low), 0},
289         {offsetof(struct acpi_battery, capacity_granularity_1), 0},
290         {offsetof(struct acpi_battery, capacity_granularity_2), 0},
291         {offsetof(struct acpi_battery, model_number), 1},
292         {offsetof(struct acpi_battery, serial_number), 1},
293         {offsetof(struct acpi_battery, type), 1},
294         {offsetof(struct acpi_battery, oem_info), 1},
295 };
296
297 static int extract_package(struct acpi_battery *battery,
298                            union acpi_object *package,
299                            struct acpi_offsets *offsets, int num)
300 {
301         int i;
302         union acpi_object *element;
303         if (package->type != ACPI_TYPE_PACKAGE)
304                 return -EFAULT;
305         for (i = 0; i < num; ++i) {
306                 if (package->package.count <= i)
307                         return -EFAULT;
308                 element = &package->package.elements[i];
309                 if (offsets[i].mode) {
310                         u8 *ptr = (u8 *)battery + offsets[i].offset;
311                         if (element->type == ACPI_TYPE_STRING ||
312                             element->type == ACPI_TYPE_BUFFER)
313                                 strncpy(ptr, element->string.pointer, 32);
314                         else if (element->type == ACPI_TYPE_INTEGER) {
315                                 strncpy(ptr, (u8 *)&element->integer.value,
316                                         sizeof(acpi_integer));
317                                 ptr[sizeof(acpi_integer)] = 0;
318                         } else
319                                 *ptr = 0; /* don't have value */
320                 } else {
321                         int *x = (int *)((u8 *)battery + offsets[i].offset);
322                         *x = (element->type == ACPI_TYPE_INTEGER) ?
323                                 element->integer.value : -1;
324                 }
325         }
326         return 0;
327 }
328
329 static int acpi_battery_get_status(struct acpi_battery *battery)
330 {
331         if (acpi_bus_get_status(battery->device)) {
332                 ACPI_EXCEPTION((AE_INFO, AE_ERROR, "Evaluating _STA"));
333                 return -ENODEV;
334         }
335         return 0;
336 }
337
338 static int acpi_battery_get_info(struct acpi_battery *battery)
339 {
340         int result = -EFAULT;
341         acpi_status status = 0;
342         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
343
344         if (!acpi_battery_present(battery))
345                 return 0;
346         mutex_lock(&battery->lock);
347         status = acpi_evaluate_object(battery->device->handle, "_BIF",
348                                       NULL, &buffer);
349         mutex_unlock(&battery->lock);
350
351         if (ACPI_FAILURE(status)) {
352                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BIF"));
353                 return -ENODEV;
354         }
355
356         result = extract_package(battery, buffer.pointer,
357                                  info_offsets, ARRAY_SIZE(info_offsets));
358         kfree(buffer.pointer);
359         return result;
360 }
361
362 static int acpi_battery_get_state(struct acpi_battery *battery)
363 {
364         int result = 0;
365         acpi_status status = 0;
366         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
367
368         if (!acpi_battery_present(battery))
369                 return 0;
370
371         if (battery->update_time &&
372             time_before(jiffies, battery->update_time +
373                         msecs_to_jiffies(cache_time)))
374                 return 0;
375
376         mutex_lock(&battery->lock);
377         status = acpi_evaluate_object(battery->device->handle, "_BST",
378                                       NULL, &buffer);
379         mutex_unlock(&battery->lock);
380
381         if (ACPI_FAILURE(status)) {
382                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BST"));
383                 return -ENODEV;
384         }
385
386         result = extract_package(battery, buffer.pointer,
387                                  state_offsets, ARRAY_SIZE(state_offsets));
388         battery->update_time = jiffies;
389         kfree(buffer.pointer);
390         return result;
391 }
392
393 static int acpi_battery_set_alarm(struct acpi_battery *battery)
394 {
395         acpi_status status = 0;
396         union acpi_object arg0 = { .type = ACPI_TYPE_INTEGER };
397         struct acpi_object_list arg_list = { 1, &arg0 };
398
399         if (!acpi_battery_present(battery)|| !battery->alarm_present)
400                 return -ENODEV;
401
402         arg0.integer.value = battery->alarm;
403
404         mutex_lock(&battery->lock);
405         status = acpi_evaluate_object(battery->device->handle, "_BTP",
406                                  &arg_list, NULL);
407         mutex_unlock(&battery->lock);
408
409         if (ACPI_FAILURE(status))
410                 return -ENODEV;
411
412         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Alarm set to %d\n", battery->alarm));
413         return 0;
414 }
415
416 static int acpi_battery_init_alarm(struct acpi_battery *battery)
417 {
418         acpi_status status = AE_OK;
419         acpi_handle handle = NULL;
420
421         /* See if alarms are supported, and if so, set default */
422         status = acpi_get_handle(battery->device->handle, "_BTP", &handle);
423         if (ACPI_FAILURE(status)) {
424                 battery->alarm_present = 0;
425                 return 0;
426         }
427         battery->alarm_present = 1;
428         if (!battery->alarm)
429                 battery->alarm = battery->design_capacity_warning;
430         return acpi_battery_set_alarm(battery);
431 }
432
433 #ifdef CONFIG_ACPI_SYSFS_POWER
434 static ssize_t acpi_battery_alarm_show(struct device *dev,
435                                         struct device_attribute *attr,
436                                         char *buf)
437 {
438         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
439         return sprintf(buf, "%d\n", battery->alarm * 1000);
440 }
441
442 static ssize_t acpi_battery_alarm_store(struct device *dev,
443                                         struct device_attribute *attr,
444                                         const char *buf, size_t count)
445 {
446         unsigned long x;
447         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
448         if (sscanf(buf, "%ld\n", &x) == 1)
449                 battery->alarm = x/1000;
450         if (acpi_battery_present(battery))
451                 acpi_battery_set_alarm(battery);
452         return count;
453 }
454
455 static struct device_attribute alarm_attr = {
456         .attr = {.name = "alarm", .mode = 0644},
457         .show = acpi_battery_alarm_show,
458         .store = acpi_battery_alarm_store,
459 };
460
461 static int sysfs_add_battery(struct acpi_battery *battery)
462 {
463         int result;
464
465         if (battery->power_unit) {
466                 battery->bat.properties = charge_battery_props;
467                 battery->bat.num_properties =
468                         ARRAY_SIZE(charge_battery_props);
469         } else {
470                 battery->bat.properties = energy_battery_props;
471                 battery->bat.num_properties =
472                         ARRAY_SIZE(energy_battery_props);
473         }
474
475         battery->bat.name = acpi_device_bid(battery->device);
476         battery->bat.type = POWER_SUPPLY_TYPE_BATTERY;
477         battery->bat.get_property = acpi_battery_get_property;
478
479         result = power_supply_register(&battery->device->dev, &battery->bat);
480         if (result)
481                 return result;
482         return device_create_file(battery->bat.dev, &alarm_attr);
483 }
484
485 static void sysfs_remove_battery(struct acpi_battery *battery)
486 {
487         if (!battery->bat.dev)
488                 return;
489         device_remove_file(battery->bat.dev, &alarm_attr);
490         power_supply_unregister(&battery->bat);
491         battery->bat.dev = NULL;
492 }
493 #endif
494
495 static int acpi_battery_update(struct acpi_battery *battery)
496 {
497         int result, old_present = acpi_battery_present(battery);
498         result = acpi_battery_get_status(battery);
499         if (result)
500                 return result;
501 #ifdef CONFIG_ACPI_SYSFS_POWER
502         if (!acpi_battery_present(battery)) {
503                 sysfs_remove_battery(battery);
504                 battery->update_time = 0;
505                 return 0;
506         }
507 #endif
508         if (!battery->update_time ||
509             old_present != acpi_battery_present(battery)) {
510                 result = acpi_battery_get_info(battery);
511                 if (result)
512                         return result;
513                 acpi_battery_init_alarm(battery);
514         }
515 #ifdef CONFIG_ACPI_SYSFS_POWER
516         if (!battery->bat.dev)
517                 sysfs_add_battery(battery);
518 #endif
519         return acpi_battery_get_state(battery);
520 }
521
522 /* --------------------------------------------------------------------------
523                               FS Interface (/proc)
524    -------------------------------------------------------------------------- */
525
526 #ifdef CONFIG_ACPI_PROCFS_POWER
527 static struct proc_dir_entry *acpi_battery_dir;
528
529 static int acpi_battery_print_info(struct seq_file *seq, int result)
530 {
531         struct acpi_battery *battery = seq->private;
532
533         if (result)
534                 goto end;
535
536         seq_printf(seq, "present:                 %s\n",
537                    acpi_battery_present(battery)?"yes":"no");
538         if (!acpi_battery_present(battery))
539                 goto end;
540         if (battery->design_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
541                 seq_printf(seq, "design capacity:         unknown\n");
542         else
543                 seq_printf(seq, "design capacity:         %d %sh\n",
544                            battery->design_capacity,
545                            acpi_battery_units(battery));
546
547         if (battery->full_charge_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
548                 seq_printf(seq, "last full capacity:      unknown\n");
549         else
550                 seq_printf(seq, "last full capacity:      %d %sh\n",
551                            battery->full_charge_capacity,
552                            acpi_battery_units(battery));
553
554         seq_printf(seq, "battery technology:      %srechargeable\n",
555                    (!battery->technology)?"non-":"");
556
557         if (battery->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
558                 seq_printf(seq, "design voltage:          unknown\n");
559         else
560                 seq_printf(seq, "design voltage:          %d mV\n",
561                            battery->design_voltage);
562         seq_printf(seq, "design capacity warning: %d %sh\n",
563                    battery->design_capacity_warning,
564                    acpi_battery_units(battery));
565         seq_printf(seq, "design capacity low:     %d %sh\n",
566                    battery->design_capacity_low,
567                    acpi_battery_units(battery));
568         seq_printf(seq, "capacity granularity 1:  %d %sh\n",
569                    battery->capacity_granularity_1,
570                    acpi_battery_units(battery));
571         seq_printf(seq, "capacity granularity 2:  %d %sh\n",
572                    battery->capacity_granularity_2,
573                    acpi_battery_units(battery));
574         seq_printf(seq, "model number:            %s\n", battery->model_number);
575         seq_printf(seq, "serial number:           %s\n", battery->serial_number);
576         seq_printf(seq, "battery type:            %s\n", battery->type);
577         seq_printf(seq, "OEM info:                %s\n", battery->oem_info);
578       end:
579         if (result)
580                 seq_printf(seq, "ERROR: Unable to read battery info\n");
581         return result;
582 }
583
584 static int acpi_battery_print_state(struct seq_file *seq, int result)
585 {
586         struct acpi_battery *battery = seq->private;
587
588         if (result)
589                 goto end;
590
591         seq_printf(seq, "present:                 %s\n",
592                    acpi_battery_present(battery)?"yes":"no");
593         if (!acpi_battery_present(battery))
594                 goto end;
595
596         seq_printf(seq, "capacity state:          %s\n",
597                         (battery->state & 0x04)?"critical":"ok");
598         if ((battery->state & 0x01) && (battery->state & 0x02))
599                 seq_printf(seq,
600                            "charging state:          charging/discharging\n");
601         else if (battery->state & 0x01)
602                 seq_printf(seq, "charging state:          discharging\n");
603         else if (battery->state & 0x02)
604                 seq_printf(seq, "charging state:          charging\n");
605         else
606                 seq_printf(seq, "charging state:          charged\n");
607
608         if (battery->current_now == ACPI_BATTERY_VALUE_UNKNOWN)
609                 seq_printf(seq, "present rate:            unknown\n");
610         else
611                 seq_printf(seq, "present rate:            %d %s\n",
612                            battery->current_now, acpi_battery_units(battery));
613
614         if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN)
615                 seq_printf(seq, "remaining capacity:      unknown\n");
616         else
617                 seq_printf(seq, "remaining capacity:      %d %sh\n",
618                            battery->capacity_now, acpi_battery_units(battery));
619         if (battery->voltage_now == ACPI_BATTERY_VALUE_UNKNOWN)
620                 seq_printf(seq, "present voltage:         unknown\n");
621         else
622                 seq_printf(seq, "present voltage:         %d mV\n",
623                            battery->voltage_now);
624       end:
625         if (result)
626                 seq_printf(seq, "ERROR: Unable to read battery state\n");
627
628         return result;
629 }
630
631 static int acpi_battery_print_alarm(struct seq_file *seq, int result)
632 {
633         struct acpi_battery *battery = seq->private;
634
635         if (result)
636                 goto end;
637
638         if (!acpi_battery_present(battery)) {
639                 seq_printf(seq, "present:                 no\n");
640                 goto end;
641         }
642         seq_printf(seq, "alarm:                   ");
643         if (!battery->alarm)
644                 seq_printf(seq, "unsupported\n");
645         else
646                 seq_printf(seq, "%u %sh\n", battery->alarm,
647                                 acpi_battery_units(battery));
648       end:
649         if (result)
650                 seq_printf(seq, "ERROR: Unable to read battery alarm\n");
651         return result;
652 }
653
654 static ssize_t acpi_battery_write_alarm(struct file *file,
655                                         const char __user * buffer,
656                                         size_t count, loff_t * ppos)
657 {
658         int result = 0;
659         char alarm_string[12] = { '\0' };
660         struct seq_file *m = file->private_data;
661         struct acpi_battery *battery = m->private;
662
663         if (!battery || (count > sizeof(alarm_string) - 1))
664                 return -EINVAL;
665         if (!acpi_battery_present(battery)) {
666                 result = -ENODEV;
667                 goto end;
668         }
669         if (copy_from_user(alarm_string, buffer, count)) {
670                 result = -EFAULT;
671                 goto end;
672         }
673         alarm_string[count] = '\0';
674         battery->alarm = simple_strtol(alarm_string, NULL, 0);
675         result = acpi_battery_set_alarm(battery);
676       end:
677         if (!result)
678                 return count;
679         return result;
680 }
681
682 typedef int(*print_func)(struct seq_file *seq, int result);
683
684 static print_func acpi_print_funcs[ACPI_BATTERY_NUMFILES] = {
685         acpi_battery_print_info,
686         acpi_battery_print_state,
687         acpi_battery_print_alarm,
688 };
689
690 static int acpi_battery_read(int fid, struct seq_file *seq)
691 {
692         struct acpi_battery *battery = seq->private;
693         int result = acpi_battery_update(battery);
694         return acpi_print_funcs[fid](seq, result);
695 }
696
697 #define DECLARE_FILE_FUNCTIONS(_name) \
698 static int acpi_battery_read_##_name(struct seq_file *seq, void *offset) \
699 { \
700         return acpi_battery_read(_name##_tag, seq); \
701 } \
702 static int acpi_battery_##_name##_open_fs(struct inode *inode, struct file *file) \
703 { \
704         return single_open(file, acpi_battery_read_##_name, PDE(inode)->data); \
705 }
706
707 DECLARE_FILE_FUNCTIONS(info);
708 DECLARE_FILE_FUNCTIONS(state);
709 DECLARE_FILE_FUNCTIONS(alarm);
710
711 #undef DECLARE_FILE_FUNCTIONS
712
713 #define FILE_DESCRIPTION_RO(_name) \
714         { \
715         .name = __stringify(_name), \
716         .mode = S_IRUGO, \
717         .ops = { \
718                 .open = acpi_battery_##_name##_open_fs, \
719                 .read = seq_read, \
720                 .llseek = seq_lseek, \
721                 .release = single_release, \
722                 .owner = THIS_MODULE, \
723                 }, \
724         }
725
726 #define FILE_DESCRIPTION_RW(_name) \
727         { \
728         .name = __stringify(_name), \
729         .mode = S_IFREG | S_IRUGO | S_IWUSR, \
730         .ops = { \
731                 .open = acpi_battery_##_name##_open_fs, \
732                 .read = seq_read, \
733                 .llseek = seq_lseek, \
734                 .write = acpi_battery_write_##_name, \
735                 .release = single_release, \
736                 .owner = THIS_MODULE, \
737                 }, \
738         }
739
740 static struct battery_file {
741         struct file_operations ops;
742         mode_t mode;
743         const char *name;
744 } acpi_battery_file[] = {
745         FILE_DESCRIPTION_RO(info),
746         FILE_DESCRIPTION_RO(state),
747         FILE_DESCRIPTION_RW(alarm),
748 };
749
750 #undef FILE_DESCRIPTION_RO
751 #undef FILE_DESCRIPTION_RW
752
753 static int acpi_battery_add_fs(struct acpi_device *device)
754 {
755         struct proc_dir_entry *entry = NULL;
756         int i;
757
758         if (!acpi_device_dir(device)) {
759                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
760                                                      acpi_battery_dir);
761                 if (!acpi_device_dir(device))
762                         return -ENODEV;
763                 acpi_device_dir(device)->owner = THIS_MODULE;
764         }
765
766         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i) {
767                 entry = proc_create_data(acpi_battery_file[i].name,
768                                          acpi_battery_file[i].mode,
769                                          acpi_device_dir(device),
770                                          &acpi_battery_file[i].ops,
771                                          acpi_driver_data(device));
772                 if (!entry)
773                         return -ENODEV;
774         }
775         return 0;
776 }
777
778 static void acpi_battery_remove_fs(struct acpi_device *device)
779 {
780         int i;
781         if (!acpi_device_dir(device))
782                 return;
783         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i)
784                 remove_proc_entry(acpi_battery_file[i].name,
785                                   acpi_device_dir(device));
786
787         remove_proc_entry(acpi_device_bid(device), acpi_battery_dir);
788         acpi_device_dir(device) = NULL;
789 }
790
791 #endif
792
793 /* --------------------------------------------------------------------------
794                                  Driver Interface
795    -------------------------------------------------------------------------- */
796
797 static void acpi_battery_notify(acpi_handle handle, u32 event, void *data)
798 {
799         struct acpi_battery *battery = data;
800         struct acpi_device *device;
801         if (!battery)
802                 return;
803         device = battery->device;
804         acpi_battery_update(battery);
805         acpi_bus_generate_proc_event(device, event,
806                                      acpi_battery_present(battery));
807         acpi_bus_generate_netlink_event(device->pnp.device_class,
808                                         dev_name(&device->dev), event,
809                                         acpi_battery_present(battery));
810 #ifdef CONFIG_ACPI_SYSFS_POWER
811         /* acpi_batter_update could remove power_supply object */
812         if (battery->bat.dev)
813                 kobject_uevent(&battery->bat.dev->kobj, KOBJ_CHANGE);
814 #endif
815 }
816
817 static int acpi_battery_add(struct acpi_device *device)
818 {
819         int result = 0;
820         acpi_status status = 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         if (result)
836                 goto end;
837 #endif
838         status = acpi_install_notify_handler(device->handle,
839                                              ACPI_ALL_NOTIFY,
840                                              acpi_battery_notify, battery);
841         if (ACPI_FAILURE(status)) {
842                 ACPI_EXCEPTION((AE_INFO, status, "Installing notify handler"));
843                 result = -ENODEV;
844                 goto end;
845         }
846         printk(KERN_INFO PREFIX "%s Slot [%s] (battery %s)\n",
847                ACPI_BATTERY_DEVICE_NAME, acpi_device_bid(device),
848                device->status.battery_present ? "present" : "absent");
849       end:
850         if (result) {
851 #ifdef CONFIG_ACPI_PROCFS_POWER
852                 acpi_battery_remove_fs(device);
853 #endif
854                 kfree(battery);
855         }
856         return result;
857 }
858
859 static int acpi_battery_remove(struct acpi_device *device, int type)
860 {
861         acpi_status status = 0;
862         struct acpi_battery *battery = NULL;
863
864         if (!device || !acpi_driver_data(device))
865                 return -EINVAL;
866         battery = acpi_driver_data(device);
867         status = acpi_remove_notify_handler(device->handle,
868                                             ACPI_ALL_NOTIFY,
869                                             acpi_battery_notify);
870 #ifdef CONFIG_ACPI_PROCFS_POWER
871         acpi_battery_remove_fs(device);
872 #endif
873 #ifdef CONFIG_ACPI_SYSFS_POWER
874         sysfs_remove_battery(battery);
875 #endif
876         mutex_destroy(&battery->lock);
877         kfree(battery);
878         return 0;
879 }
880
881 /* this is needed to learn about changes made in suspended state */
882 static int acpi_battery_resume(struct acpi_device *device)
883 {
884         struct acpi_battery *battery;
885         if (!device)
886                 return -EINVAL;
887         battery = acpi_driver_data(device);
888         battery->update_time = 0;
889         acpi_battery_update(battery);
890         return 0;
891 }
892
893 static struct acpi_driver acpi_battery_driver = {
894         .name = "battery",
895         .class = ACPI_BATTERY_CLASS,
896         .ids = battery_device_ids,
897         .ops = {
898                 .add = acpi_battery_add,
899                 .resume = acpi_battery_resume,
900                 .remove = acpi_battery_remove,
901                 },
902 };
903
904 static int __init acpi_battery_init(void)
905 {
906         if (acpi_disabled)
907                 return -ENODEV;
908 #ifdef CONFIG_ACPI_PROCFS_POWER
909         acpi_battery_dir = acpi_lock_battery_dir();
910         if (!acpi_battery_dir)
911                 return -ENODEV;
912 #endif
913         if (acpi_bus_register_driver(&acpi_battery_driver) < 0) {
914 #ifdef CONFIG_ACPI_PROCFS_POWER
915                 acpi_unlock_battery_dir(acpi_battery_dir);
916 #endif
917                 return -ENODEV;
918         }
919         return 0;
920 }
921
922 static void __exit acpi_battery_exit(void)
923 {
924         acpi_bus_unregister_driver(&acpi_battery_driver);
925 #ifdef CONFIG_ACPI_PROCFS_POWER
926         acpi_unlock_battery_dir(acpi_battery_dir);
927 #endif
928 }
929
930 module_init(acpi_battery_init);
931 module_exit(acpi_battery_exit);