Merge branch 'merge'
[linux-2.6] / drivers / acpi / battery.c
1 /*
2  *  acpi_battery.c - ACPI Battery Driver ($Revision: 37 $)
3  *
4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6  *
7  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8  *
9  *  This program is free software; you can redistribute it and/or modify
10  *  it under the terms of the GNU General Public License as published by
11  *  the Free Software Foundation; either version 2 of the License, or (at
12  *  your option) any later version.
13  *
14  *  This program is distributed in the hope that it will be useful, but
15  *  WITHOUT ANY WARRANTY; without even the implied warranty of
16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  *  General Public License for more details.
18  *
19  *  You should have received a copy of the GNU General Public License along
20  *  with this program; if not, write to the Free Software Foundation, Inc.,
21  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
22  *
23  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
24  */
25
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28 #include <linux/init.h>
29 #include <linux/types.h>
30 #include <linux/proc_fs.h>
31 #include <linux/seq_file.h>
32 #include <asm/uaccess.h>
33
34 #include <acpi/acpi_bus.h>
35 #include <acpi/acpi_drivers.h>
36
37 #define ACPI_BATTERY_VALUE_UNKNOWN 0xFFFFFFFF
38
39 #define ACPI_BATTERY_FORMAT_BIF "NNNNNNNNNSSSS"
40 #define ACPI_BATTERY_FORMAT_BST "NNNN"
41
42 #define ACPI_BATTERY_COMPONENT          0x00040000
43 #define ACPI_BATTERY_CLASS              "battery"
44 #define ACPI_BATTERY_HID                "PNP0C0A"
45 #define ACPI_BATTERY_DRIVER_NAME        "ACPI Battery Driver"
46 #define ACPI_BATTERY_DEVICE_NAME        "Battery"
47 #define ACPI_BATTERY_FILE_INFO          "info"
48 #define ACPI_BATTERY_FILE_STATUS        "state"
49 #define ACPI_BATTERY_FILE_ALARM         "alarm"
50 #define ACPI_BATTERY_NOTIFY_STATUS      0x80
51 #define ACPI_BATTERY_NOTIFY_INFO        0x81
52 #define ACPI_BATTERY_UNITS_WATTS        "mW"
53 #define ACPI_BATTERY_UNITS_AMPS         "mA"
54
55 #define _COMPONENT              ACPI_BATTERY_COMPONENT
56 ACPI_MODULE_NAME("acpi_battery")
57
58     MODULE_AUTHOR("Paul Diefenbaugh");
59 MODULE_DESCRIPTION(ACPI_BATTERY_DRIVER_NAME);
60 MODULE_LICENSE("GPL");
61
62 extern struct proc_dir_entry *acpi_lock_battery_dir(void);
63 extern void *acpi_unlock_battery_dir(struct proc_dir_entry *acpi_battery_dir);
64
65 static int acpi_battery_add(struct acpi_device *device);
66 static int acpi_battery_remove(struct acpi_device *device, int type);
67
68 static struct acpi_driver acpi_battery_driver = {
69         .name = ACPI_BATTERY_DRIVER_NAME,
70         .class = ACPI_BATTERY_CLASS,
71         .ids = ACPI_BATTERY_HID,
72         .ops = {
73                 .add = acpi_battery_add,
74                 .remove = acpi_battery_remove,
75                 },
76 };
77
78 struct acpi_battery_status {
79         acpi_integer state;
80         acpi_integer present_rate;
81         acpi_integer remaining_capacity;
82         acpi_integer present_voltage;
83 };
84
85 struct acpi_battery_info {
86         acpi_integer power_unit;
87         acpi_integer design_capacity;
88         acpi_integer last_full_capacity;
89         acpi_integer battery_technology;
90         acpi_integer design_voltage;
91         acpi_integer design_capacity_warning;
92         acpi_integer design_capacity_low;
93         acpi_integer battery_capacity_granularity_1;
94         acpi_integer battery_capacity_granularity_2;
95         acpi_string model_number;
96         acpi_string serial_number;
97         acpi_string battery_type;
98         acpi_string oem_info;
99 };
100
101 struct acpi_battery_flags {
102         u8 present:1;           /* Bay occupied? */
103         u8 power_unit:1;        /* 0=watts, 1=apms */
104         u8 alarm:1;             /* _BTP present? */
105         u8 reserved:5;
106 };
107
108 struct acpi_battery_trips {
109         unsigned long warning;
110         unsigned long low;
111 };
112
113 struct acpi_battery {
114         struct acpi_device * device;
115         struct acpi_battery_flags flags;
116         struct acpi_battery_trips trips;
117         unsigned long alarm;
118         struct acpi_battery_info *info;
119 };
120
121 /* --------------------------------------------------------------------------
122                                Battery Management
123    -------------------------------------------------------------------------- */
124
125 static int
126 acpi_battery_get_info(struct acpi_battery *battery,
127                       struct acpi_battery_info **bif)
128 {
129         int result = 0;
130         acpi_status status = 0;
131         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
132         struct acpi_buffer format = { sizeof(ACPI_BATTERY_FORMAT_BIF),
133                 ACPI_BATTERY_FORMAT_BIF
134         };
135         struct acpi_buffer data = { 0, NULL };
136         union acpi_object *package = NULL;
137
138
139         if (!battery || !bif)
140                 return -EINVAL;
141
142         /* Evalute _BIF */
143
144         status = acpi_evaluate_object(battery->device->handle, "_BIF", NULL, &buffer);
145         if (ACPI_FAILURE(status)) {
146                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BIF"));
147                 return -ENODEV;
148         }
149
150         package = (union acpi_object *)buffer.pointer;
151
152         /* Extract Package Data */
153
154         status = acpi_extract_package(package, &format, &data);
155         if (status != AE_BUFFER_OVERFLOW) {
156                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _BIF"));
157                 result = -ENODEV;
158                 goto end;
159         }
160
161         data.pointer = kmalloc(data.length, GFP_KERNEL);
162         if (!data.pointer) {
163                 result = -ENOMEM;
164                 goto end;
165         }
166         memset(data.pointer, 0, data.length);
167
168         status = acpi_extract_package(package, &format, &data);
169         if (ACPI_FAILURE(status)) {
170                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _BIF"));
171                 kfree(data.pointer);
172                 result = -ENODEV;
173                 goto end;
174         }
175
176       end:
177         kfree(buffer.pointer);
178
179         if (!result)
180                 (*bif) = (struct acpi_battery_info *)data.pointer;
181
182         return result;
183 }
184
185 static int
186 acpi_battery_get_status(struct acpi_battery *battery,
187                         struct acpi_battery_status **bst)
188 {
189         int result = 0;
190         acpi_status status = 0;
191         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
192         struct acpi_buffer format = { sizeof(ACPI_BATTERY_FORMAT_BST),
193                 ACPI_BATTERY_FORMAT_BST
194         };
195         struct acpi_buffer data = { 0, NULL };
196         union acpi_object *package = NULL;
197
198
199         if (!battery || !bst)
200                 return -EINVAL;
201
202         /* Evalute _BST */
203
204         status = acpi_evaluate_object(battery->device->handle, "_BST", NULL, &buffer);
205         if (ACPI_FAILURE(status)) {
206                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BST"));
207                 return -ENODEV;
208         }
209
210         package = (union acpi_object *)buffer.pointer;
211
212         /* Extract Package Data */
213
214         status = acpi_extract_package(package, &format, &data);
215         if (status != AE_BUFFER_OVERFLOW) {
216                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _BST"));
217                 result = -ENODEV;
218                 goto end;
219         }
220
221         data.pointer = kmalloc(data.length, GFP_KERNEL);
222         if (!data.pointer) {
223                 result = -ENOMEM;
224                 goto end;
225         }
226         memset(data.pointer, 0, data.length);
227
228         status = acpi_extract_package(package, &format, &data);
229         if (ACPI_FAILURE(status)) {
230                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _BST"));
231                 kfree(data.pointer);
232                 result = -ENODEV;
233                 goto end;
234         }
235
236       end:
237         kfree(buffer.pointer);
238
239         if (!result)
240                 (*bst) = (struct acpi_battery_status *)data.pointer;
241
242         return result;
243 }
244
245 static int
246 acpi_battery_set_alarm(struct acpi_battery *battery, unsigned long alarm)
247 {
248         acpi_status status = 0;
249         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
250         struct acpi_object_list arg_list = { 1, &arg0 };
251
252
253         if (!battery)
254                 return -EINVAL;
255
256         if (!battery->flags.alarm)
257                 return -ENODEV;
258
259         arg0.integer.value = alarm;
260
261         status = acpi_evaluate_object(battery->device->handle, "_BTP", &arg_list, NULL);
262         if (ACPI_FAILURE(status))
263                 return -ENODEV;
264
265         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Alarm set to %d\n", (u32) alarm));
266
267         battery->alarm = alarm;
268
269         return 0;
270 }
271
272 static int acpi_battery_check(struct acpi_battery *battery)
273 {
274         int result = 0;
275         acpi_status status = AE_OK;
276         acpi_handle handle = NULL;
277         struct acpi_device *device = NULL;
278         struct acpi_battery_info *bif = NULL;
279
280
281         if (!battery)
282                 return -EINVAL;
283
284         device = battery->device;
285
286         result = acpi_bus_get_status(device);
287         if (result)
288                 return result;
289
290         /* Insertion? */
291
292         if (!battery->flags.present && device->status.battery_present) {
293
294                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Battery inserted\n"));
295
296                 /* Evalute _BIF to get certain static information */
297
298                 result = acpi_battery_get_info(battery, &bif);
299                 if (result)
300                         return result;
301
302                 battery->flags.power_unit = bif->power_unit;
303                 battery->trips.warning = bif->design_capacity_warning;
304                 battery->trips.low = bif->design_capacity_low;
305                 kfree(bif);
306
307                 /* See if alarms are supported, and if so, set default */
308
309                 status = acpi_get_handle(battery->device->handle, "_BTP", &handle);
310                 if (ACPI_SUCCESS(status)) {
311                         battery->flags.alarm = 1;
312                         acpi_battery_set_alarm(battery, battery->trips.warning);
313                 }
314         }
315
316         /* Removal? */
317
318         else if (battery->flags.present && !device->status.battery_present) {
319                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Battery removed\n"));
320         }
321
322         battery->flags.present = device->status.battery_present;
323
324         return result;
325 }
326
327 /* --------------------------------------------------------------------------
328                               FS Interface (/proc)
329    -------------------------------------------------------------------------- */
330
331 static struct proc_dir_entry *acpi_battery_dir;
332 static int acpi_battery_read_info(struct seq_file *seq, void *offset)
333 {
334         int result = 0;
335         struct acpi_battery *battery = (struct acpi_battery *)seq->private;
336         struct acpi_battery_info *bif = NULL;
337         char *units = "?";
338
339
340         if (!battery)
341                 goto end;
342
343         if (battery->flags.present)
344                 seq_printf(seq, "present:                 yes\n");
345         else {
346                 seq_printf(seq, "present:                 no\n");
347                 goto end;
348         }
349
350         /* Battery Info (_BIF) */
351
352         result = acpi_battery_get_info(battery, &bif);
353         if (result || !bif) {
354                 seq_printf(seq, "ERROR: Unable to read battery information\n");
355                 goto end;
356         }
357
358         units =
359             bif->
360             power_unit ? ACPI_BATTERY_UNITS_AMPS : ACPI_BATTERY_UNITS_WATTS;
361
362         if (bif->design_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
363                 seq_printf(seq, "design capacity:         unknown\n");
364         else
365                 seq_printf(seq, "design capacity:         %d %sh\n",
366                            (u32) bif->design_capacity, units);
367
368         if (bif->last_full_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
369                 seq_printf(seq, "last full capacity:      unknown\n");
370         else
371                 seq_printf(seq, "last full capacity:      %d %sh\n",
372                            (u32) bif->last_full_capacity, units);
373
374         switch ((u32) bif->battery_technology) {
375         case 0:
376                 seq_printf(seq, "battery technology:      non-rechargeable\n");
377                 break;
378         case 1:
379                 seq_printf(seq, "battery technology:      rechargeable\n");
380                 break;
381         default:
382                 seq_printf(seq, "battery technology:      unknown\n");
383                 break;
384         }
385
386         if (bif->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
387                 seq_printf(seq, "design voltage:          unknown\n");
388         else
389                 seq_printf(seq, "design voltage:          %d mV\n",
390                            (u32) bif->design_voltage);
391
392         seq_printf(seq, "design capacity warning: %d %sh\n",
393                    (u32) bif->design_capacity_warning, units);
394         seq_printf(seq, "design capacity low:     %d %sh\n",
395                    (u32) bif->design_capacity_low, units);
396         seq_printf(seq, "capacity granularity 1:  %d %sh\n",
397                    (u32) bif->battery_capacity_granularity_1, units);
398         seq_printf(seq, "capacity granularity 2:  %d %sh\n",
399                    (u32) bif->battery_capacity_granularity_2, units);
400         seq_printf(seq, "model number:            %s\n", bif->model_number);
401         seq_printf(seq, "serial number:           %s\n", bif->serial_number);
402         seq_printf(seq, "battery type:            %s\n", bif->battery_type);
403         seq_printf(seq, "OEM info:                %s\n", bif->oem_info);
404
405       end:
406         kfree(bif);
407
408         return 0;
409 }
410
411 static int acpi_battery_info_open_fs(struct inode *inode, struct file *file)
412 {
413         return single_open(file, acpi_battery_read_info, PDE(inode)->data);
414 }
415
416 static int acpi_battery_read_state(struct seq_file *seq, void *offset)
417 {
418         int result = 0;
419         struct acpi_battery *battery = (struct acpi_battery *)seq->private;
420         struct acpi_battery_status *bst = NULL;
421         char *units = "?";
422
423
424         if (!battery)
425                 goto end;
426
427         if (battery->flags.present)
428                 seq_printf(seq, "present:                 yes\n");
429         else {
430                 seq_printf(seq, "present:                 no\n");
431                 goto end;
432         }
433
434         /* Battery Units */
435
436         units =
437             battery->flags.
438             power_unit ? ACPI_BATTERY_UNITS_AMPS : ACPI_BATTERY_UNITS_WATTS;
439
440         /* Battery Status (_BST) */
441
442         result = acpi_battery_get_status(battery, &bst);
443         if (result || !bst) {
444                 seq_printf(seq, "ERROR: Unable to read battery status\n");
445                 goto end;
446         }
447
448         if (!(bst->state & 0x04))
449                 seq_printf(seq, "capacity state:          ok\n");
450         else
451                 seq_printf(seq, "capacity state:          critical\n");
452
453         if ((bst->state & 0x01) && (bst->state & 0x02)) {
454                 seq_printf(seq,
455                            "charging state:          charging/discharging\n");
456         } else if (bst->state & 0x01)
457                 seq_printf(seq, "charging state:          discharging\n");
458         else if (bst->state & 0x02)
459                 seq_printf(seq, "charging state:          charging\n");
460         else {
461                 seq_printf(seq, "charging state:          charged\n");
462         }
463
464         if (bst->present_rate == ACPI_BATTERY_VALUE_UNKNOWN)
465                 seq_printf(seq, "present rate:            unknown\n");
466         else
467                 seq_printf(seq, "present rate:            %d %s\n",
468                            (u32) bst->present_rate, units);
469
470         if (bst->remaining_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
471                 seq_printf(seq, "remaining capacity:      unknown\n");
472         else
473                 seq_printf(seq, "remaining capacity:      %d %sh\n",
474                            (u32) bst->remaining_capacity, units);
475
476         if (bst->present_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
477                 seq_printf(seq, "present voltage:         unknown\n");
478         else
479                 seq_printf(seq, "present voltage:         %d mV\n",
480                            (u32) bst->present_voltage);
481
482       end:
483         kfree(bst);
484
485         return 0;
486 }
487
488 static int acpi_battery_state_open_fs(struct inode *inode, struct file *file)
489 {
490         return single_open(file, acpi_battery_read_state, PDE(inode)->data);
491 }
492
493 static int acpi_battery_read_alarm(struct seq_file *seq, void *offset)
494 {
495         struct acpi_battery *battery = (struct acpi_battery *)seq->private;
496         char *units = "?";
497
498
499         if (!battery)
500                 goto end;
501
502         if (!battery->flags.present) {
503                 seq_printf(seq, "present:                 no\n");
504                 goto end;
505         }
506
507         /* Battery Units */
508
509         units =
510             battery->flags.
511             power_unit ? ACPI_BATTERY_UNITS_AMPS : ACPI_BATTERY_UNITS_WATTS;
512
513         /* Battery Alarm */
514
515         seq_printf(seq, "alarm:                   ");
516         if (!battery->alarm)
517                 seq_printf(seq, "unsupported\n");
518         else
519                 seq_printf(seq, "%d %sh\n", (u32) battery->alarm, units);
520
521       end:
522         return 0;
523 }
524
525 static ssize_t
526 acpi_battery_write_alarm(struct file *file,
527                          const char __user * buffer,
528                          size_t count, loff_t * ppos)
529 {
530         int result = 0;
531         char alarm_string[12] = { '\0' };
532         struct seq_file *m = (struct seq_file *)file->private_data;
533         struct acpi_battery *battery = (struct acpi_battery *)m->private;
534
535
536         if (!battery || (count > sizeof(alarm_string) - 1))
537                 return -EINVAL;
538
539         if (!battery->flags.present)
540                 return -ENODEV;
541
542         if (copy_from_user(alarm_string, buffer, count))
543                 return -EFAULT;
544
545         alarm_string[count] = '\0';
546
547         result = acpi_battery_set_alarm(battery,
548                                         simple_strtoul(alarm_string, NULL, 0));
549         if (result)
550                 return result;
551
552         return count;
553 }
554
555 static int acpi_battery_alarm_open_fs(struct inode *inode, struct file *file)
556 {
557         return single_open(file, acpi_battery_read_alarm, PDE(inode)->data);
558 }
559
560 static const struct file_operations acpi_battery_info_ops = {
561         .open = acpi_battery_info_open_fs,
562         .read = seq_read,
563         .llseek = seq_lseek,
564         .release = single_release,
565         .owner = THIS_MODULE,
566 };
567
568 static const struct file_operations acpi_battery_state_ops = {
569         .open = acpi_battery_state_open_fs,
570         .read = seq_read,
571         .llseek = seq_lseek,
572         .release = single_release,
573         .owner = THIS_MODULE,
574 };
575
576 static const struct file_operations acpi_battery_alarm_ops = {
577         .open = acpi_battery_alarm_open_fs,
578         .read = seq_read,
579         .write = acpi_battery_write_alarm,
580         .llseek = seq_lseek,
581         .release = single_release,
582         .owner = THIS_MODULE,
583 };
584
585 static int acpi_battery_add_fs(struct acpi_device *device)
586 {
587         struct proc_dir_entry *entry = NULL;
588
589
590         if (!acpi_device_dir(device)) {
591                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
592                                                      acpi_battery_dir);
593                 if (!acpi_device_dir(device))
594                         return -ENODEV;
595                 acpi_device_dir(device)->owner = THIS_MODULE;
596         }
597
598         /* 'info' [R] */
599         entry = create_proc_entry(ACPI_BATTERY_FILE_INFO,
600                                   S_IRUGO, acpi_device_dir(device));
601         if (!entry)
602                 return -ENODEV;
603         else {
604                 entry->proc_fops = &acpi_battery_info_ops;
605                 entry->data = acpi_driver_data(device);
606                 entry->owner = THIS_MODULE;
607         }
608
609         /* 'status' [R] */
610         entry = create_proc_entry(ACPI_BATTERY_FILE_STATUS,
611                                   S_IRUGO, acpi_device_dir(device));
612         if (!entry)
613                 return -ENODEV;
614         else {
615                 entry->proc_fops = &acpi_battery_state_ops;
616                 entry->data = acpi_driver_data(device);
617                 entry->owner = THIS_MODULE;
618         }
619
620         /* 'alarm' [R/W] */
621         entry = create_proc_entry(ACPI_BATTERY_FILE_ALARM,
622                                   S_IFREG | S_IRUGO | S_IWUSR,
623                                   acpi_device_dir(device));
624         if (!entry)
625                 return -ENODEV;
626         else {
627                 entry->proc_fops = &acpi_battery_alarm_ops;
628                 entry->data = acpi_driver_data(device);
629                 entry->owner = THIS_MODULE;
630         }
631
632         return 0;
633 }
634
635 static int acpi_battery_remove_fs(struct acpi_device *device)
636 {
637
638         if (acpi_device_dir(device)) {
639                 remove_proc_entry(ACPI_BATTERY_FILE_ALARM,
640                                   acpi_device_dir(device));
641                 remove_proc_entry(ACPI_BATTERY_FILE_STATUS,
642                                   acpi_device_dir(device));
643                 remove_proc_entry(ACPI_BATTERY_FILE_INFO,
644                                   acpi_device_dir(device));
645
646                 remove_proc_entry(acpi_device_bid(device), acpi_battery_dir);
647                 acpi_device_dir(device) = NULL;
648         }
649
650         return 0;
651 }
652
653 /* --------------------------------------------------------------------------
654                                  Driver Interface
655    -------------------------------------------------------------------------- */
656
657 static void acpi_battery_notify(acpi_handle handle, u32 event, void *data)
658 {
659         struct acpi_battery *battery = (struct acpi_battery *)data;
660         struct acpi_device *device = NULL;
661
662
663         if (!battery)
664                 return;
665
666         device = battery->device;
667
668         switch (event) {
669         case ACPI_BATTERY_NOTIFY_STATUS:
670         case ACPI_BATTERY_NOTIFY_INFO:
671         case ACPI_NOTIFY_BUS_CHECK:
672         case ACPI_NOTIFY_DEVICE_CHECK:
673                 acpi_battery_check(battery);
674                 acpi_bus_generate_event(device, event, battery->flags.present);
675                 break;
676         default:
677                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
678                                   "Unsupported event [0x%x]\n", event));
679                 break;
680         }
681
682         return;
683 }
684
685 static int acpi_battery_add(struct acpi_device *device)
686 {
687         int result = 0;
688         acpi_status status = 0;
689         struct acpi_battery *battery = NULL;
690
691
692         if (!device)
693                 return -EINVAL;
694
695         battery = kmalloc(sizeof(struct acpi_battery), GFP_KERNEL);
696         if (!battery)
697                 return -ENOMEM;
698         memset(battery, 0, sizeof(struct acpi_battery));
699
700         battery->device = device;
701         strcpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
702         strcpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
703         acpi_driver_data(device) = battery;
704
705         result = acpi_battery_check(battery);
706         if (result)
707                 goto end;
708
709         result = acpi_battery_add_fs(device);
710         if (result)
711                 goto end;
712
713         status = acpi_install_notify_handler(device->handle,
714                                              ACPI_ALL_NOTIFY,
715                                              acpi_battery_notify, battery);
716         if (ACPI_FAILURE(status)) {
717                 result = -ENODEV;
718                 goto end;
719         }
720
721         printk(KERN_INFO PREFIX "%s Slot [%s] (battery %s)\n",
722                ACPI_BATTERY_DEVICE_NAME, acpi_device_bid(device),
723                device->status.battery_present ? "present" : "absent");
724
725       end:
726         if (result) {
727                 acpi_battery_remove_fs(device);
728                 kfree(battery);
729         }
730
731         return result;
732 }
733
734 static int acpi_battery_remove(struct acpi_device *device, int type)
735 {
736         acpi_status status = 0;
737         struct acpi_battery *battery = NULL;
738
739
740         if (!device || !acpi_driver_data(device))
741                 return -EINVAL;
742
743         battery = (struct acpi_battery *)acpi_driver_data(device);
744
745         status = acpi_remove_notify_handler(device->handle,
746                                             ACPI_ALL_NOTIFY,
747                                             acpi_battery_notify);
748
749         acpi_battery_remove_fs(device);
750
751         kfree(battery);
752
753         return 0;
754 }
755
756 static int __init acpi_battery_init(void)
757 {
758         int result;
759
760         acpi_battery_dir = acpi_lock_battery_dir();
761         if (!acpi_battery_dir)
762                 return -ENODEV;
763
764         result = acpi_bus_register_driver(&acpi_battery_driver);
765         if (result < 0) {
766                 acpi_unlock_battery_dir(acpi_battery_dir);
767                 return -ENODEV;
768         }
769
770         return 0;
771 }
772
773 static void __exit acpi_battery_exit(void)
774 {
775
776         acpi_bus_unregister_driver(&acpi_battery_driver);
777
778         acpi_unlock_battery_dir(acpi_battery_dir);
779
780         return;
781 }
782
783 module_init(acpi_battery_init);
784 module_exit(acpi_battery_exit);