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