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_DEVICE_NAME        "Battery"
  46 #define ACPI_BATTERY_FILE_INFO          "info"
  47 #define ACPI_BATTERY_FILE_STATUS        "state"
  48 #define ACPI_BATTERY_FILE_ALARM         "alarm"
  49 #define ACPI_BATTERY_NOTIFY_STATUS      0x80
  50 #define ACPI_BATTERY_NOTIFY_INFO        0x81
  51 #define ACPI_BATTERY_UNITS_WATTS        "mW"
  52 #define ACPI_BATTERY_UNITS_AMPS         "mA"
  53
  54 #define _COMPONENT              ACPI_BATTERY_COMPONENT
  55 ACPI_MODULE_NAME("battery");
  56
  57 MODULE_AUTHOR("Paul Diefenbaugh");
  58 MODULE_DESCRIPTION("ACPI Battery Driver");
  59 MODULE_LICENSE("GPL");
  60
  61 extern struct proc_dir_entry *acpi_lock_battery_dir(void);
  62 extern void *acpi_unlock_battery_dir(struct proc_dir_entry *acpi_battery_dir);
  63
  64 static int acpi_battery_add(struct acpi_device *device);
  65 static int acpi_battery_remove(struct acpi_device *device, int type);
  66 static int acpi_battery_resume(struct acpi_device *device);
  67
  68 static struct acpi_driver acpi_battery_driver = {
  69         .name = "battery",
  70         .class = ACPI_BATTERY_CLASS,
  71         .ids = ACPI_BATTERY_HID,
  72         .ops = {
  73                 .add = acpi_battery_add,
  74                 .resume = acpi_battery_resume,
  75                 .remove = acpi_battery_remove,
  76                 },
  77 };
  78
  79 struct acpi_battery_status {
  80         acpi_integer state;
  81         acpi_integer present_rate;
  82         acpi_integer remaining_capacity;
  83         acpi_integer present_voltage;
  84 };
  85
  86 struct acpi_battery_info {
  87         acpi_integer power_unit;
  88         acpi_integer design_capacity;
  89         acpi_integer last_full_capacity;
  90         acpi_integer battery_technology;
  91         acpi_integer design_voltage;
  92         acpi_integer design_capacity_warning;
  93         acpi_integer design_capacity_low;
  94         acpi_integer battery_capacity_granularity_1;
  95         acpi_integer battery_capacity_granularity_2;
  96         acpi_string model_number;
  97         acpi_string serial_number;
  98         acpi_string battery_type;
  99         acpi_string oem_info;
 100 };
 101
 102 struct acpi_battery_flags {
 103         u8 present:1;           /* Bay occupied? */
 104         u8 power_unit:1;        /* 0=watts, 1=apms */
 105         u8 alarm:1;             /* _BTP present? */
 106         u8 reserved:5;
 107 };
 108
 109 struct acpi_battery_trips {
 110         unsigned long warning;
 111         unsigned long low;
 112 };
 113
 114 struct acpi_battery {
 115         struct acpi_device * device;
 116         struct acpi_battery_flags flags;
 117         struct acpi_battery_trips trips;
 118         unsigned long alarm;
 119         struct acpi_battery_info *info;
 120 };
 121
 122 /* --------------------------------------------------------------------------
 123                                Battery Management
 124    -------------------------------------------------------------------------- */
 125
 126 static int
 127 acpi_battery_get_info(struct acpi_battery *battery,
 128                       struct acpi_battery_info **bif)
 129 {
 130         int result = 0;
 131         acpi_status status = 0;
 132         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 133         struct acpi_buffer format = { sizeof(ACPI_BATTERY_FORMAT_BIF),
 134                 ACPI_BATTERY_FORMAT_BIF
 135         };
 136         struct acpi_buffer data = { 0, NULL };
 137         union acpi_object *package = NULL;
 138
 139
 140         if (!battery || !bif)
 141                 return -EINVAL;
 142
 143         /* Evalute _BIF */
 144
 145         status = acpi_evaluate_object(battery->device->handle, "_BIF", NULL, &buffer);
 146         if (ACPI_FAILURE(status)) {
 147                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BIF"));
 148                 return -ENODEV;
 149         }
 150
 151         package = buffer.pointer;
 152
 153         /* Extract Package Data */
 154
 155         status = acpi_extract_package(package, &format, &data);
 156         if (status != AE_BUFFER_OVERFLOW) {
 157                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _BIF"));
 158                 result = -ENODEV;
 159                 goto end;
 160         }
 161
 162         data.pointer = kzalloc(data.length, GFP_KERNEL);
 163         if (!data.pointer) {
 164                 result = -ENOMEM;
 165                 goto end;
 166         }
 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) = 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 = 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 = kzalloc(data.length, GFP_KERNEL);
 222         if (!data.pointer) {
 223                 result = -ENOMEM;
 224                 goto end;
 225         }
 226
 227         status = acpi_extract_package(package, &format, &data);
 228         if (ACPI_FAILURE(status)) {
 229                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _BST"));
 230                 kfree(data.pointer);
 231                 result = -ENODEV;
 232                 goto end;
 233         }
 234
 235       end:
 236         kfree(buffer.pointer);
 237
 238         if (!result)
 239                 (*bst) = data.pointer;
 240
 241         return result;
 242 }
 243
 244 static int
 245 acpi_battery_set_alarm(struct acpi_battery *battery, unsigned long alarm)
 246 {
 247         acpi_status status = 0;
 248         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
 249         struct acpi_object_list arg_list = { 1, &arg0 };
 250
 251
 252         if (!battery)
 253                 return -EINVAL;
 254
 255         if (!battery->flags.alarm)
 256                 return -ENODEV;
 257
 258         arg0.integer.value = alarm;
 259
 260         status = acpi_evaluate_object(battery->device->handle, "_BTP", &arg_list, NULL);
 261         if (ACPI_FAILURE(status))
 262                 return -ENODEV;
 263
 264         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Alarm set to %d\n", (u32) alarm));
 265
 266         battery->alarm = alarm;
 267
 268         return 0;
 269 }
 270
 271 static int acpi_battery_check(struct acpi_battery *battery)
 272 {
 273         int result = 0;
 274         acpi_status status = AE_OK;
 275         acpi_handle handle = NULL;
 276         struct acpi_device *device = NULL;
 277         struct acpi_battery_info *bif = NULL;
 278
 279
 280         if (!battery)
 281                 return -EINVAL;
 282
 283         device = battery->device;
 284
 285         result = acpi_bus_get_status(device);
 286         if (result)
 287                 return result;
 288
 289         /* Insertion? */
 290
 291         if (!battery->flags.present && device->status.battery_present) {
 292
 293                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Battery inserted\n"));
 294
 295                 /* Evalute _BIF to get certain static information */
 296
 297                 result = acpi_battery_get_info(battery, &bif);
 298                 if (result)
 299                         return result;
 300
 301                 battery->flags.power_unit = bif->power_unit;
 302                 battery->trips.warning = bif->design_capacity_warning;
 303                 battery->trips.low = bif->design_capacity_low;
 304                 kfree(bif);
 305
 306                 /* See if alarms are supported, and if so, set default */
 307
 308                 status = acpi_get_handle(battery->device->handle, "_BTP", &handle);
 309                 if (ACPI_SUCCESS(status)) {
 310                         battery->flags.alarm = 1;
 311                         acpi_battery_set_alarm(battery, battery->trips.warning);
 312                 }
 313         }
 314
 315         /* Removal? */
 316
 317         else if (battery->flags.present && !device->status.battery_present) {
 318                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Battery removed\n"));
 319         }
 320
 321         battery->flags.present = device->status.battery_present;
 322
 323         return result;
 324 }
 325
 326 static void acpi_battery_check_present(struct acpi_battery *battery)
 327 {
 328         if (!battery->flags.present) {
 329                 acpi_battery_check(battery);
 330         }
 331 }
 332
 333 /* --------------------------------------------------------------------------
 334                               FS Interface (/proc)
 335    -------------------------------------------------------------------------- */
 336
 337 static struct proc_dir_entry *acpi_battery_dir;
 338 static int acpi_battery_read_info(struct seq_file *seq, void *offset)
 339 {
 340         int result = 0;
 341         struct acpi_battery *battery = seq->private;
 342         struct acpi_battery_info *bif = NULL;
 343         char *units = "?";
 344
 345
 346         if (!battery)
 347                 goto end;
 348
 349         acpi_battery_check_present(battery);
 350
 351         if (battery->flags.present)
 352                 seq_printf(seq, "present:                 yes\n");
 353         else {
 354                 seq_printf(seq, "present:                 no\n");
 355                 goto end;
 356         }
 357
 358         /* Battery Info (_BIF) */
 359
 360         result = acpi_battery_get_info(battery, &bif);
 361         if (result || !bif) {
 362                 seq_printf(seq, "ERROR: Unable to read battery information\n");
 363                 goto end;
 364         }
 365
 366         units =
 367             bif->
 368             power_unit ? ACPI_BATTERY_UNITS_AMPS : ACPI_BATTERY_UNITS_WATTS;
 369
 370         if (bif->design_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
 371                 seq_printf(seq, "design capacity:         unknown\n");
 372         else
 373                 seq_printf(seq, "design capacity:         %d %sh\n",
 374                            (u32) bif->design_capacity, units);
 375
 376         if (bif->last_full_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
 377                 seq_printf(seq, "last full capacity:      unknown\n");
 378         else
 379                 seq_printf(seq, "last full capacity:      %d %sh\n",
 380                            (u32) bif->last_full_capacity, units);
 381
 382         switch ((u32) bif->battery_technology) {
 383         case 0:
 384                 seq_printf(seq, "battery technology:      non-rechargeable\n");
 385                 break;
 386         case 1:
 387                 seq_printf(seq, "battery technology:      rechargeable\n");
 388                 break;
 389         default:
 390                 seq_printf(seq, "battery technology:      unknown\n");
 391                 break;
 392         }
 393
 394         if (bif->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
 395                 seq_printf(seq, "design voltage:          unknown\n");
 396         else
 397                 seq_printf(seq, "design voltage:          %d mV\n",
 398                            (u32) bif->design_voltage);
 399
 400         seq_printf(seq, "design capacity warning: %d %sh\n",
 401                    (u32) bif->design_capacity_warning, units);
 402         seq_printf(seq, "design capacity low:     %d %sh\n",
 403                    (u32) bif->design_capacity_low, units);
 404         seq_printf(seq, "capacity granularity 1:  %d %sh\n",
 405                    (u32) bif->battery_capacity_granularity_1, units);
 406         seq_printf(seq, "capacity granularity 2:  %d %sh\n",
 407                    (u32) bif->battery_capacity_granularity_2, units);
 408         seq_printf(seq, "model number:            %s\n", bif->model_number);
 409         seq_printf(seq, "serial number:           %s\n", bif->serial_number);
 410         seq_printf(seq, "battery type:            %s\n", bif->battery_type);
 411         seq_printf(seq, "OEM info:                %s\n", bif->oem_info);
 412
 413       end:
 414         kfree(bif);
 415
 416         return 0;
 417 }
 418
 419 static int acpi_battery_info_open_fs(struct inode *inode, struct file *file)
 420 {
 421         return single_open(file, acpi_battery_read_info, PDE(inode)->data);
 422 }
 423
 424 static int acpi_battery_read_state(struct seq_file *seq, void *offset)
 425 {
 426         int result = 0;
 427         struct acpi_battery *battery = seq->private;
 428         struct acpi_battery_status *bst = NULL;
 429         char *units = "?";
 430
 431
 432         if (!battery)
 433                 goto end;
 434
 435         acpi_battery_check_present(battery);
 436
 437         if (battery->flags.present)
 438                 seq_printf(seq, "present:                 yes\n");
 439         else {
 440                 seq_printf(seq, "present:                 no\n");
 441                 goto end;
 442         }
 443
 444         /* Battery Units */
 445
 446         units =
 447             battery->flags.
 448             power_unit ? ACPI_BATTERY_UNITS_AMPS : ACPI_BATTERY_UNITS_WATTS;
 449
 450         /* Battery Status (_BST) */
 451
 452         result = acpi_battery_get_status(battery, &bst);
 453         if (result || !bst) {
 454                 seq_printf(seq, "ERROR: Unable to read battery status\n");
 455                 goto end;
 456         }
 457
 458         if (!(bst->state & 0x04))
 459                 seq_printf(seq, "capacity state:          ok\n");
 460         else
 461                 seq_printf(seq, "capacity state:          critical\n");
 462
 463         if ((bst->state & 0x01) && (bst->state & 0x02)) {
 464                 seq_printf(seq,
 465                            "charging state:          charging/discharging\n");
 466         } else if (bst->state & 0x01)
 467                 seq_printf(seq, "charging state:          discharging\n");
 468         else if (bst->state & 0x02)
 469                 seq_printf(seq, "charging state:          charging\n");
 470         else {
 471                 seq_printf(seq, "charging state:          charged\n");
 472         }
 473
 474         if (bst->present_rate == ACPI_BATTERY_VALUE_UNKNOWN)
 475                 seq_printf(seq, "present rate:            unknown\n");
 476         else
 477                 seq_printf(seq, "present rate:            %d %s\n",
 478                            (u32) bst->present_rate, units);
 479
 480         if (bst->remaining_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
 481                 seq_printf(seq, "remaining capacity:      unknown\n");
 482         else
 483                 seq_printf(seq, "remaining capacity:      %d %sh\n",
 484                            (u32) bst->remaining_capacity, units);
 485
 486         if (bst->present_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
 487                 seq_printf(seq, "present voltage:         unknown\n");
 488         else
 489                 seq_printf(seq, "present voltage:         %d mV\n",
 490                            (u32) bst->present_voltage);
 491
 492       end:
 493         kfree(bst);
 494
 495         return 0;
 496 }
 497
 498 static int acpi_battery_state_open_fs(struct inode *inode, struct file *file)
 499 {
 500         return single_open(file, acpi_battery_read_state, PDE(inode)->data);
 501 }
 502
 503 static int acpi_battery_read_alarm(struct seq_file *seq, void *offset)
 504 {
 505         struct acpi_battery *battery = seq->private;
 506         char *units = "?";
 507
 508
 509         if (!battery)
 510                 goto end;
 511
 512         acpi_battery_check_present(battery);
 513
 514         if (!battery->flags.present) {
 515                 seq_printf(seq, "present:                 no\n");
 516                 goto end;
 517         }
 518
 519         /* Battery Units */
 520
 521         units =
 522             battery->flags.
 523             power_unit ? ACPI_BATTERY_UNITS_AMPS : ACPI_BATTERY_UNITS_WATTS;
 524
 525         /* Battery Alarm */
 526
 527         seq_printf(seq, "alarm:                   ");
 528         if (!battery->alarm)
 529                 seq_printf(seq, "unsupported\n");
 530         else
 531                 seq_printf(seq, "%d %sh\n", (u32) battery->alarm, units);
 532
 533       end:
 534         return 0;
 535 }
 536
 537 static ssize_t
 538 acpi_battery_write_alarm(struct file *file,
 539                          const char __user * buffer,
 540                          size_t count, loff_t * ppos)
 541 {
 542         int result = 0;
 543         char alarm_string[12] = { '\0' };
 544         struct seq_file *m = file->private_data;
 545         struct acpi_battery *battery = m->private;
 546
 547
 548         if (!battery || (count > sizeof(alarm_string) - 1))
 549                 return -EINVAL;
 550
 551         acpi_battery_check_present(battery);
 552
 553         if (!battery->flags.present)
 554                 return -ENODEV;
 555
 556         if (copy_from_user(alarm_string, buffer, count))
 557                 return -EFAULT;
 558
 559         alarm_string[count] = '\0';
 560
 561         result = acpi_battery_set_alarm(battery,
 562                                         simple_strtoul(alarm_string, NULL, 0));
 563         if (result)
 564                 return result;
 565
 566         return count;
 567 }
 568
 569 static int acpi_battery_alarm_open_fs(struct inode *inode, struct file *file)
 570 {
 571         return single_open(file, acpi_battery_read_alarm, PDE(inode)->data);
 572 }
 573
 574 static const struct file_operations acpi_battery_info_ops = {
 575         .open = acpi_battery_info_open_fs,
 576         .read = seq_read,
 577         .llseek = seq_lseek,
 578         .release = single_release,
 579         .owner = THIS_MODULE,
 580 };
 581
 582 static const struct file_operations acpi_battery_state_ops = {
 583         .open = acpi_battery_state_open_fs,
 584         .read = seq_read,
 585         .llseek = seq_lseek,
 586         .release = single_release,
 587         .owner = THIS_MODULE,
 588 };
 589
 590 static const struct file_operations acpi_battery_alarm_ops = {
 591         .open = acpi_battery_alarm_open_fs,
 592         .read = seq_read,
 593         .write = acpi_battery_write_alarm,
 594         .llseek = seq_lseek,
 595         .release = single_release,
 596         .owner = THIS_MODULE,
 597 };
 598
 599 static int acpi_battery_add_fs(struct acpi_device *device)
 600 {
 601         struct proc_dir_entry *entry = NULL;
 602
 603
 604         if (!acpi_device_dir(device)) {
 605                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 606                                                      acpi_battery_dir);
 607                 if (!acpi_device_dir(device))
 608                         return -ENODEV;
 609                 acpi_device_dir(device)->owner = THIS_MODULE;
 610         }
 611
 612         /* 'info' [R] */
 613         entry = create_proc_entry(ACPI_BATTERY_FILE_INFO,
 614                                   S_IRUGO, acpi_device_dir(device));
 615         if (!entry)
 616                 return -ENODEV;
 617         else {
 618                 entry->proc_fops = &acpi_battery_info_ops;
 619                 entry->data = acpi_driver_data(device);
 620                 entry->owner = THIS_MODULE;
 621         }
 622
 623         /* 'status' [R] */
 624         entry = create_proc_entry(ACPI_BATTERY_FILE_STATUS,
 625                                   S_IRUGO, acpi_device_dir(device));
 626         if (!entry)
 627                 return -ENODEV;
 628         else {
 629                 entry->proc_fops = &acpi_battery_state_ops;
 630                 entry->data = acpi_driver_data(device);
 631                 entry->owner = THIS_MODULE;
 632         }
 633
 634         /* 'alarm' [R/W] */
 635         entry = create_proc_entry(ACPI_BATTERY_FILE_ALARM,
 636                                   S_IFREG | S_IRUGO | S_IWUSR,
 637                                   acpi_device_dir(device));
 638         if (!entry)
 639                 return -ENODEV;
 640         else {
 641                 entry->proc_fops = &acpi_battery_alarm_ops;
 642                 entry->data = acpi_driver_data(device);
 643                 entry->owner = THIS_MODULE;
 644         }
 645
 646         return 0;
 647 }
 648
 649 static int acpi_battery_remove_fs(struct acpi_device *device)
 650 {
 651
 652         if (acpi_device_dir(device)) {
 653                 remove_proc_entry(ACPI_BATTERY_FILE_ALARM,
 654                                   acpi_device_dir(device));
 655                 remove_proc_entry(ACPI_BATTERY_FILE_STATUS,
 656                                   acpi_device_dir(device));
 657                 remove_proc_entry(ACPI_BATTERY_FILE_INFO,
 658                                   acpi_device_dir(device));
 659
 660                 remove_proc_entry(acpi_device_bid(device), acpi_battery_dir);
 661                 acpi_device_dir(device) = NULL;
 662         }
 663
 664         return 0;
 665 }
 666
 667 /* --------------------------------------------------------------------------
 668                                  Driver Interface
 669    -------------------------------------------------------------------------- */
 670
 671 static void acpi_battery_notify(acpi_handle handle, u32 event, void *data)
 672 {
 673         struct acpi_battery *battery = data;
 674         struct acpi_device *device = NULL;
 675
 676
 677         if (!battery)
 678                 return;
 679
 680         device = battery->device;
 681
 682         switch (event) {
 683         case ACPI_BATTERY_NOTIFY_STATUS:
 684         case ACPI_BATTERY_NOTIFY_INFO:
 685         case ACPI_NOTIFY_BUS_CHECK:
 686         case ACPI_NOTIFY_DEVICE_CHECK:
 687                 acpi_battery_check(battery);
 688                 acpi_bus_generate_event(device, event, battery->flags.present);
 689                 break;
 690         default:
 691                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 692                                   "Unsupported event [0x%x]\n", event));
 693                 break;
 694         }
 695
 696         return;
 697 }
 698
 699 static int acpi_battery_add(struct acpi_device *device)
 700 {
 701         int result = 0;
 702         acpi_status status = 0;
 703         struct acpi_battery *battery = NULL;
 704
 705
 706         if (!device)
 707                 return -EINVAL;
 708
 709         battery = kzalloc(sizeof(struct acpi_battery), GFP_KERNEL);
 710         if (!battery)
 711                 return -ENOMEM;
 712
 713         battery->device = device;
 714         strcpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
 715         strcpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
 716         acpi_driver_data(device) = battery;
 717
 718         result = acpi_battery_check(battery);
 719         if (result)
 720                 goto end;
 721
 722         result = acpi_battery_add_fs(device);
 723         if (result)
 724                 goto end;
 725
 726         status = acpi_install_notify_handler(device->handle,
 727                                              ACPI_ALL_NOTIFY,
 728                                              acpi_battery_notify, battery);
 729         if (ACPI_FAILURE(status)) {
 730                 result = -ENODEV;
 731                 goto end;
 732         }
 733
 734         printk(KERN_INFO PREFIX "%s Slot [%s] (battery %s)\n",
 735                ACPI_BATTERY_DEVICE_NAME, acpi_device_bid(device),
 736                device->status.battery_present ? "present" : "absent");
 737
 738       end:
 739         if (result) {
 740                 acpi_battery_remove_fs(device);
 741                 kfree(battery);
 742         }
 743
 744         return result;
 745 }
 746
 747 static int acpi_battery_remove(struct acpi_device *device, int type)
 748 {
 749         acpi_status status = 0;
 750         struct acpi_battery *battery = NULL;
 751
 752
 753         if (!device || !acpi_driver_data(device))
 754                 return -EINVAL;
 755
 756         battery = acpi_driver_data(device);
 757
 758         status = acpi_remove_notify_handler(device->handle,
 759                                             ACPI_ALL_NOTIFY,
 760                                             acpi_battery_notify);
 761
 762         acpi_battery_remove_fs(device);
 763
 764         kfree(battery);
 765
 766         return 0;
 767 }
 768
 769 /* this is needed to learn about changes made in suspended state */
 770 static int acpi_battery_resume(struct acpi_device *device)
 771 {
 772         struct acpi_battery *battery;
 773
 774         if (!device)
 775                 return -EINVAL;
 776
 777         battery = device->driver_data;
 778         return acpi_battery_check(battery);
 779 }
 780
 781 static int __init acpi_battery_init(void)
 782 {
 783         int result;
 784
 785         if (acpi_disabled)
 786                 return -ENODEV;
 787
 788         acpi_battery_dir = acpi_lock_battery_dir();
 789         if (!acpi_battery_dir)
 790                 return -ENODEV;
 791
 792         result = acpi_bus_register_driver(&acpi_battery_driver);
 793         if (result < 0) {
 794                 acpi_unlock_battery_dir(acpi_battery_dir);
 795                 return -ENODEV;
 796         }
 797
 798         return 0;
 799 }
 800
 801 static void __exit acpi_battery_exit(void)
 802 {
 803
 804         acpi_bus_unregister_driver(&acpi_battery_driver);
 805
 806         acpi_unlock_battery_dir(acpi_battery_dir);
 807
 808         return;
 809 }
 810
 811 module_init(acpi_battery_init);
 812 module_exit(acpi_battery_exit);