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