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_DEVICE_NAME        "Battery"
  45 #define ACPI_BATTERY_NOTIFY_STATUS      0x80
  46 #define ACPI_BATTERY_NOTIFY_INFO        0x81
  47 #define ACPI_BATTERY_UNITS_WATTS        "mW"
  48 #define ACPI_BATTERY_UNITS_AMPS         "mA"
  49
  50 #define _COMPONENT              ACPI_BATTERY_COMPONENT
  51
  52 #define ACPI_BATTERY_UPDATE_TIME        0
  53
  54 #define ACPI_BATTERY_NONE_UPDATE        0
  55 #define ACPI_BATTERY_EASY_UPDATE        1
  56 #define ACPI_BATTERY_INIT_UPDATE        2
  57
  58 ACPI_MODULE_NAME("battery");
  59
  60 MODULE_AUTHOR("Paul Diefenbaugh");
  61 MODULE_DESCRIPTION("ACPI Battery Driver");
  62 MODULE_LICENSE("GPL");
  63
  64 static unsigned int update_time = ACPI_BATTERY_UPDATE_TIME;
  65
  66 /* 0 - every time, > 0 - by update_time */
  67 module_param(update_time, uint, 0644);
  68
  69 extern struct proc_dir_entry *acpi_lock_battery_dir(void);
  70 extern void *acpi_unlock_battery_dir(struct proc_dir_entry *acpi_battery_dir);
  71
  72 static int acpi_battery_add(struct acpi_device *device);
  73 static int acpi_battery_remove(struct acpi_device *device, int type);
  74 static int acpi_battery_resume(struct acpi_device *device);
  75
  76 static const struct acpi_device_id battery_device_ids[] = {
  77         {"PNP0C0A", 0},
  78         {"", 0},
  79 };
  80 MODULE_DEVICE_TABLE(acpi, battery_device_ids);
  81
  82 static struct acpi_driver acpi_battery_driver = {
  83         .name = "battery",
  84         .class = ACPI_BATTERY_CLASS,
  85         .ids = battery_device_ids,
  86         .ops = {
  87                 .add = acpi_battery_add,
  88                 .resume = acpi_battery_resume,
  89                 .remove = acpi_battery_remove,
  90                 },
  91 };
  92
  93 struct acpi_battery_state {
  94         acpi_integer state;
  95         acpi_integer present_rate;
  96         acpi_integer remaining_capacity;
  97         acpi_integer present_voltage;
  98 };
  99
 100 struct acpi_battery_info {
 101         acpi_integer power_unit;
 102         acpi_integer design_capacity;
 103         acpi_integer last_full_capacity;
 104         acpi_integer battery_technology;
 105         acpi_integer design_voltage;
 106         acpi_integer design_capacity_warning;
 107         acpi_integer design_capacity_low;
 108         acpi_integer battery_capacity_granularity_1;
 109         acpi_integer battery_capacity_granularity_2;
 110         acpi_string model_number;
 111         acpi_string serial_number;
 112         acpi_string battery_type;
 113         acpi_string oem_info;
 114 };
 115
 116 enum acpi_battery_files{
 117         ACPI_BATTERY_INFO = 0,
 118         ACPI_BATTERY_STATE,
 119         ACPI_BATTERY_ALARM,
 120         ACPI_BATTERY_NUMFILES,
 121 };
 122
 123 struct acpi_battery_flags {
 124         u8 battery_present_prev;
 125         u8 alarm_present;
 126         u8 init_update;
 127         u8 update[ACPI_BATTERY_NUMFILES];
 128         u8 power_unit;
 129 };
 130
 131 struct acpi_battery {
 132         struct mutex mutex;
 133         struct acpi_device *device;
 134         struct acpi_battery_flags flags;
 135         struct acpi_buffer bif_data;
 136         struct acpi_buffer bst_data;
 137         unsigned long alarm;
 138         unsigned long update_time[ACPI_BATTERY_NUMFILES];
 139 };
 140
 141 inline int acpi_battery_present(struct acpi_battery *battery)
 142 {
 143         return battery->device->status.battery_present;
 144 }
 145 inline char *acpi_battery_power_units(struct acpi_battery *battery)
 146 {
 147         if (battery->flags.power_unit)
 148                 return ACPI_BATTERY_UNITS_AMPS;
 149         else
 150                 return ACPI_BATTERY_UNITS_WATTS;
 151 }
 152
 153 inline acpi_handle acpi_battery_handle(struct acpi_battery *battery)
 154 {
 155         return battery->device->handle;
 156 }
 157
 158 /* --------------------------------------------------------------------------
 159                                Battery Management
 160    -------------------------------------------------------------------------- */
 161
 162 static void acpi_battery_check_result(struct acpi_battery *battery, int result)
 163 {
 164         if (!battery)
 165                 return;
 166
 167         if (result) {
 168                 battery->flags.init_update = 1;
 169         }
 170 }
 171
 172 static int acpi_battery_extract_package(struct acpi_battery *battery,
 173                                         union acpi_object *package,
 174                                         struct acpi_buffer *format,
 175                                         struct acpi_buffer *data,
 176                                         char *package_name)
 177 {
 178         acpi_status status = AE_OK;
 179         struct acpi_buffer data_null = { 0, NULL };
 180
 181         status = acpi_extract_package(package, format, &data_null);
 182         if (status != AE_BUFFER_OVERFLOW) {
 183                 ACPI_EXCEPTION((AE_INFO, status, "Extracting size %s",
 184                                 package_name));
 185                 return -ENODEV;
 186         }
 187
 188         if (data_null.length != data->length) {
 189                 kfree(data->pointer);
 190                 data->pointer = kzalloc(data_null.length, GFP_KERNEL);
 191                 if (!data->pointer) {
 192                         ACPI_EXCEPTION((AE_INFO, AE_NO_MEMORY, "kzalloc()"));
 193                         return -ENOMEM;
 194                 }
 195                 data->length = data_null.length;
 196         }
 197
 198         status = acpi_extract_package(package, format, data);
 199         if (ACPI_FAILURE(status)) {
 200                 ACPI_EXCEPTION((AE_INFO, status, "Extracting %s",
 201                                 package_name));
 202                 return -ENODEV;
 203         }
 204
 205         return 0;
 206 }
 207
 208 static int acpi_battery_get_status(struct acpi_battery *battery)
 209 {
 210         int result = 0;
 211
 212         result = acpi_bus_get_status(battery->device);
 213         if (result) {
 214                 ACPI_EXCEPTION((AE_INFO, AE_ERROR, "Evaluating _STA"));
 215                 return -ENODEV;
 216         }
 217         return result;
 218 }
 219
 220 static int acpi_battery_get_info(struct acpi_battery *battery)
 221 {
 222         int result = 0;
 223         acpi_status status = 0;
 224         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 225         struct acpi_buffer format = { sizeof(ACPI_BATTERY_FORMAT_BIF),
 226                 ACPI_BATTERY_FORMAT_BIF
 227         };
 228         union acpi_object *package = NULL;
 229         struct acpi_buffer *data = NULL;
 230         struct acpi_battery_info *bif = NULL;
 231
 232         battery->update_time[ACPI_BATTERY_INFO] = get_seconds();
 233
 234         if (!acpi_battery_present(battery))
 235                 return 0;
 236
 237         /* Evaluate _BIF */
 238
 239         status =
 240             acpi_evaluate_object(acpi_battery_handle(battery), "_BIF", NULL,
 241                                  &buffer);
 242         if (ACPI_FAILURE(status)) {
 243                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BIF"));
 244                 return -ENODEV;
 245         }
 246
 247         package = buffer.pointer;
 248
 249         data = &battery->bif_data;
 250
 251         /* Extract Package Data */
 252
 253         result =
 254             acpi_battery_extract_package(battery, package, &format, data,
 255                                          "_BIF");
 256         if (result)
 257                 goto end;
 258
 259       end:
 260
 261         kfree(buffer.pointer);
 262
 263         if (!result) {
 264                 bif = data->pointer;
 265                 battery->flags.power_unit = bif->power_unit;
 266         }
 267
 268         return result;
 269 }
 270
 271 static int acpi_battery_get_state(struct acpi_battery *battery)
 272 {
 273         int result = 0;
 274         acpi_status status = 0;
 275         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 276         struct acpi_buffer format = { sizeof(ACPI_BATTERY_FORMAT_BST),
 277                 ACPI_BATTERY_FORMAT_BST
 278         };
 279         union acpi_object *package = NULL;
 280         struct acpi_buffer *data = NULL;
 281
 282         battery->update_time[ACPI_BATTERY_STATE] = get_seconds();
 283
 284         if (!acpi_battery_present(battery))
 285                 return 0;
 286
 287         /* Evaluate _BST */
 288
 289         status =
 290             acpi_evaluate_object(acpi_battery_handle(battery), "_BST", NULL,
 291                                  &buffer);
 292         if (ACPI_FAILURE(status)) {
 293                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BST"));
 294                 return -ENODEV;
 295         }
 296
 297         package = buffer.pointer;
 298
 299         data = &battery->bst_data;
 300
 301         /* Extract Package Data */
 302
 303         result =
 304             acpi_battery_extract_package(battery, package, &format, data,
 305                                          "_BST");
 306         if (result)
 307                 goto end;
 308
 309       end:
 310         kfree(buffer.pointer);
 311
 312         return result;
 313 }
 314
 315 static int acpi_battery_get_alarm(struct acpi_battery *battery)
 316 {
 317         battery->update_time[ACPI_BATTERY_ALARM] = get_seconds();
 318
 319         return 0;
 320 }
 321
 322 static int acpi_battery_set_alarm(struct acpi_battery *battery,
 323                                   unsigned long alarm)
 324 {
 325         acpi_status status = 0;
 326         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
 327         struct acpi_object_list arg_list = { 1, &arg0 };
 328
 329         battery->update_time[ACPI_BATTERY_ALARM] = get_seconds();
 330
 331         if (!acpi_battery_present(battery))
 332                 return -ENODEV;
 333
 334         if (!battery->flags.alarm_present)
 335                 return -ENODEV;
 336
 337         arg0.integer.value = alarm;
 338
 339         status =
 340             acpi_evaluate_object(acpi_battery_handle(battery), "_BTP",
 341                                  &arg_list, NULL);
 342         if (ACPI_FAILURE(status))
 343                 return -ENODEV;
 344
 345         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Alarm set to %d\n", (u32) alarm));
 346
 347         battery->alarm = alarm;
 348
 349         return 0;
 350 }
 351
 352 static int acpi_battery_init_alarm(struct acpi_battery *battery)
 353 {
 354         int result = 0;
 355         acpi_status status = AE_OK;
 356         acpi_handle handle = NULL;
 357         struct acpi_battery_info *bif = battery->bif_data.pointer;
 358         unsigned long alarm = battery->alarm;
 359
 360         /* See if alarms are supported, and if so, set default */
 361
 362         status = acpi_get_handle(acpi_battery_handle(battery), "_BTP", &handle);
 363         if (ACPI_SUCCESS(status)) {
 364                 battery->flags.alarm_present = 1;
 365                 if (!alarm && bif) {
 366                         alarm = bif->design_capacity_warning;
 367                 }
 368                 result = acpi_battery_set_alarm(battery, alarm);
 369                 if (result)
 370                         goto end;
 371         } else {
 372                 battery->flags.alarm_present = 0;
 373         }
 374
 375       end:
 376
 377         return result;
 378 }
 379
 380 static int acpi_battery_init_update(struct acpi_battery *battery)
 381 {
 382         int result = 0;
 383
 384         result = acpi_battery_get_status(battery);
 385         if (result)
 386                 return result;
 387
 388         battery->flags.battery_present_prev = acpi_battery_present(battery);
 389
 390         if (acpi_battery_present(battery)) {
 391                 result = acpi_battery_get_info(battery);
 392                 if (result)
 393                         return result;
 394                 result = acpi_battery_get_state(battery);
 395                 if (result)
 396                         return result;
 397
 398                 acpi_battery_init_alarm(battery);
 399         }
 400
 401         return result;
 402 }
 403
 404 static int acpi_battery_update(struct acpi_battery *battery,
 405                                int update, int *update_result_ptr)
 406 {
 407         int result = 0;
 408         int update_result = ACPI_BATTERY_NONE_UPDATE;
 409
 410         if (!acpi_battery_present(battery)) {
 411                 update = 1;
 412         }
 413
 414         if (battery->flags.init_update) {
 415                 result = acpi_battery_init_update(battery);
 416                 if (result)
 417                         goto end;
 418                 update_result = ACPI_BATTERY_INIT_UPDATE;
 419         } else if (update) {
 420                 result = acpi_battery_get_status(battery);
 421                 if (result)
 422                         goto end;
 423                 if ((!battery->flags.battery_present_prev & acpi_battery_present(battery))
 424                     || (battery->flags.battery_present_prev & !acpi_battery_present(battery))) {
 425                         result = acpi_battery_init_update(battery);
 426                         if (result)
 427                                 goto end;
 428                         update_result = ACPI_BATTERY_INIT_UPDATE;
 429                 } else {
 430                         update_result = ACPI_BATTERY_EASY_UPDATE;
 431                 }
 432         }
 433
 434       end:
 435
 436         battery->flags.init_update = (result != 0);
 437
 438         *update_result_ptr = update_result;
 439
 440         return result;
 441 }
 442
 443 static void acpi_battery_notify_update(struct acpi_battery *battery)
 444 {
 445         acpi_battery_get_status(battery);
 446
 447         if (battery->flags.init_update) {
 448                 return;
 449         }
 450
 451         if ((!battery->flags.battery_present_prev &
 452              acpi_battery_present(battery)) ||
 453             (battery->flags.battery_present_prev &
 454              !acpi_battery_present(battery))) {
 455                 battery->flags.init_update = 1;
 456         } else {
 457                 battery->flags.update[ACPI_BATTERY_INFO] = 1;
 458                 battery->flags.update[ACPI_BATTERY_STATE] = 1;
 459                 battery->flags.update[ACPI_BATTERY_ALARM] = 1;
 460         }
 461 }
 462
 463 /* --------------------------------------------------------------------------
 464                               FS Interface (/proc)
 465    -------------------------------------------------------------------------- */
 466
 467 static struct proc_dir_entry *acpi_battery_dir;
 468
 469 static int acpi_battery_print_info(struct seq_file *seq, int result)
 470 {
 471         struct acpi_battery *battery = seq->private;
 472         struct acpi_battery_info *bif = NULL;
 473         char *units = "?";
 474
 475         if (result)
 476                 goto end;
 477
 478         if (acpi_battery_present(battery))
 479                 seq_printf(seq, "present:                 yes\n");
 480         else {
 481                 seq_printf(seq, "present:                 no\n");
 482                 goto end;
 483         }
 484
 485         bif = battery->bif_data.pointer;
 486         if (!bif) {
 487                 ACPI_EXCEPTION((AE_INFO, AE_ERROR, "BIF buffer is NULL"));
 488                 result = -ENODEV;
 489                 goto end;
 490         }
 491
 492         /* Battery Units */
 493
 494         units = acpi_battery_power_units(battery);
 495
 496         if (bif->design_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
 497                 seq_printf(seq, "design capacity:         unknown\n");
 498         else
 499                 seq_printf(seq, "design capacity:         %d %sh\n",
 500                            (u32) bif->design_capacity, units);
 501
 502         if (bif->last_full_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
 503                 seq_printf(seq, "last full capacity:      unknown\n");
 504         else
 505                 seq_printf(seq, "last full capacity:      %d %sh\n",
 506                            (u32) bif->last_full_capacity, units);
 507
 508         switch ((u32) bif->battery_technology) {
 509         case 0:
 510                 seq_printf(seq, "battery technology:      non-rechargeable\n");
 511                 break;
 512         case 1:
 513                 seq_printf(seq, "battery technology:      rechargeable\n");
 514                 break;
 515         default:
 516                 seq_printf(seq, "battery technology:      unknown\n");
 517                 break;
 518         }
 519
 520         if (bif->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
 521                 seq_printf(seq, "design voltage:          unknown\n");
 522         else
 523                 seq_printf(seq, "design voltage:          %d mV\n",
 524                            (u32) bif->design_voltage);
 525         seq_printf(seq, "design capacity warning: %d %sh\n",
 526                    (u32) bif->design_capacity_warning, units);
 527         seq_printf(seq, "design capacity low:     %d %sh\n",
 528                    (u32) bif->design_capacity_low, units);
 529         seq_printf(seq, "capacity granularity 1:  %d %sh\n",
 530                    (u32) bif->battery_capacity_granularity_1, units);
 531         seq_printf(seq, "capacity granularity 2:  %d %sh\n",
 532                    (u32) bif->battery_capacity_granularity_2, units);
 533         seq_printf(seq, "model number:            %s\n", bif->model_number);
 534         seq_printf(seq, "serial number:           %s\n", bif->serial_number);
 535         seq_printf(seq, "battery type:            %s\n", bif->battery_type);
 536         seq_printf(seq, "OEM info:                %s\n", bif->oem_info);
 537
 538       end:
 539
 540         if (result)
 541                 seq_printf(seq, "ERROR: Unable to read battery info\n");
 542
 543         return result;
 544 }
 545
 546 static int acpi_battery_print_state(struct seq_file *seq, int result)
 547 {
 548         struct acpi_battery *battery = seq->private;
 549         struct acpi_battery_state *bst = NULL;
 550         char *units = "?";
 551
 552         if (result)
 553                 goto end;
 554
 555         if (acpi_battery_present(battery))
 556                 seq_printf(seq, "present:                 yes\n");
 557         else {
 558                 seq_printf(seq, "present:                 no\n");
 559                 goto end;
 560         }
 561
 562         bst = battery->bst_data.pointer;
 563         if (!bst) {
 564                 ACPI_EXCEPTION((AE_INFO, AE_ERROR, "BST buffer is NULL"));
 565                 result = -ENODEV;
 566                 goto end;
 567         }
 568
 569         /* Battery Units */
 570
 571         units = acpi_battery_power_units(battery);
 572
 573         if (!(bst->state & 0x04))
 574                 seq_printf(seq, "capacity state:          ok\n");
 575         else
 576                 seq_printf(seq, "capacity state:          critical\n");
 577
 578         if ((bst->state & 0x01) && (bst->state & 0x02)) {
 579                 seq_printf(seq,
 580                            "charging state:          charging/discharging\n");
 581         } else if (bst->state & 0x01)
 582                 seq_printf(seq, "charging state:          discharging\n");
 583         else if (bst->state & 0x02)
 584                 seq_printf(seq, "charging state:          charging\n");
 585         else {
 586                 seq_printf(seq, "charging state:          charged\n");
 587         }
 588
 589         if (bst->present_rate == ACPI_BATTERY_VALUE_UNKNOWN)
 590                 seq_printf(seq, "present rate:            unknown\n");
 591         else
 592                 seq_printf(seq, "present rate:            %d %s\n",
 593                            (u32) bst->present_rate, units);
 594
 595         if (bst->remaining_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
 596                 seq_printf(seq, "remaining capacity:      unknown\n");
 597         else
 598                 seq_printf(seq, "remaining capacity:      %d %sh\n",
 599                            (u32) bst->remaining_capacity, units);
 600
 601         if (bst->present_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
 602                 seq_printf(seq, "present voltage:         unknown\n");
 603         else
 604                 seq_printf(seq, "present voltage:         %d mV\n",
 605                            (u32) bst->present_voltage);
 606
 607       end:
 608
 609         if (result) {
 610                 seq_printf(seq, "ERROR: Unable to read battery state\n");
 611         }
 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         char *units = "?";
 620
 621         if (result)
 622                 goto end;
 623
 624         if (!acpi_battery_present(battery)) {
 625                 seq_printf(seq, "present:                 no\n");
 626                 goto end;
 627         }
 628
 629         /* Battery Units */
 630
 631         units = acpi_battery_power_units(battery);
 632
 633         seq_printf(seq, "alarm:                   ");
 634         if (!battery->alarm)
 635                 seq_printf(seq, "unsupported\n");
 636         else
 637                 seq_printf(seq, "%lu %sh\n", battery->alarm, units);
 638
 639       end:
 640
 641         if (result)
 642                 seq_printf(seq, "ERROR: Unable to read battery alarm\n");
 643
 644         return result;
 645 }
 646
 647 static ssize_t
 648 acpi_battery_write_alarm(struct file *file,
 649                          const char __user * buffer,
 650                          size_t count, loff_t * ppos)
 651 {
 652         int result = 0;
 653         char alarm_string[12] = { '\0' };
 654         struct seq_file *m = file->private_data;
 655         struct acpi_battery *battery = m->private;
 656         int update_result = ACPI_BATTERY_NONE_UPDATE;
 657
 658         if (!battery || (count > sizeof(alarm_string) - 1))
 659                 return -EINVAL;
 660
 661         mutex_lock(&battery->mutex);
 662
 663         result = acpi_battery_update(battery, 1, &update_result);
 664         if (result) {
 665                 result = -ENODEV;
 666                 goto end;
 667         }
 668
 669         if (!acpi_battery_present(battery)) {
 670                 result = -ENODEV;
 671                 goto end;
 672         }
 673
 674         if (copy_from_user(alarm_string, buffer, count)) {
 675                 result = -EFAULT;
 676                 goto end;
 677         }
 678
 679         alarm_string[count] = '\0';
 680
 681         result = acpi_battery_set_alarm(battery,
 682                                         simple_strtoul(alarm_string, NULL, 0));
 683         if (result)
 684                 goto end;
 685
 686       end:
 687
 688         acpi_battery_check_result(battery, result);
 689
 690         if (!result)
 691                 result = count;
 692
 693         mutex_unlock(&battery->mutex);
 694
 695         return result;
 696 }
 697
 698 typedef int(*print_func)(struct seq_file *seq, int result);
 699 typedef int(*get_func)(struct acpi_battery *battery);
 700
 701 static struct acpi_read_mux {
 702         print_func print;
 703         get_func get;
 704 } acpi_read_funcs[ACPI_BATTERY_NUMFILES] = {
 705         {.get = acpi_battery_get_info, .print = acpi_battery_print_info},
 706         {.get = acpi_battery_get_state, .print = acpi_battery_print_state},
 707         {.get = acpi_battery_get_alarm, .print = acpi_battery_print_alarm},
 708 };
 709
 710 static int acpi_battery_read(int fid, struct seq_file *seq)
 711 {
 712         struct acpi_battery *battery = seq->private;
 713         int result = 0;
 714         int update_result = ACPI_BATTERY_NONE_UPDATE;
 715         int update = 0;
 716
 717         mutex_lock(&battery->mutex);
 718
 719         update = (get_seconds() - battery->update_time[fid] >= update_time);
 720         update = (update | battery->flags.update[fid]);
 721
 722         result = acpi_battery_update(battery, update, &update_result);
 723         if (result)
 724                 goto end;
 725
 726         if (update_result == ACPI_BATTERY_EASY_UPDATE) {
 727                 result = acpi_read_funcs[fid].get(battery);
 728                 if (result)
 729                         goto end;
 730         }
 731
 732       end:
 733         result = acpi_read_funcs[fid].print(seq, result);
 734         acpi_battery_check_result(battery, result);
 735         battery->flags.update[fid] = result;
 736         mutex_unlock(&battery->mutex);
 737         return result;
 738 }
 739
 740 static int acpi_battery_read_info(struct seq_file *seq, void *offset)
 741 {
 742         return acpi_battery_read(ACPI_BATTERY_INFO, seq);
 743 }
 744
 745 static int acpi_battery_read_state(struct seq_file *seq, void *offset)
 746 {
 747         return acpi_battery_read(ACPI_BATTERY_STATE, seq);
 748 }
 749
 750 static int acpi_battery_read_alarm(struct seq_file *seq, void *offset)
 751 {
 752         return acpi_battery_read(ACPI_BATTERY_ALARM, seq);
 753 }
 754
 755 static int acpi_battery_info_open_fs(struct inode *inode, struct file *file)
 756 {
 757         return single_open(file, acpi_battery_read_info, PDE(inode)->data);
 758 }
 759
 760 static int acpi_battery_state_open_fs(struct inode *inode, struct file *file)
 761 {
 762         return single_open(file, acpi_battery_read_state, PDE(inode)->data);
 763 }
 764
 765 static int acpi_battery_alarm_open_fs(struct inode *inode, struct file *file)
 766 {
 767         return single_open(file, acpi_battery_read_alarm, PDE(inode)->data);
 768 }
 769
 770 static struct battery_file {
 771         struct file_operations ops;
 772         mode_t mode;
 773         char *name;
 774 } acpi_battery_file[] = {
 775         {
 776         .name = "info",
 777         .mode = S_IRUGO,
 778         .ops = {
 779         .open = acpi_battery_info_open_fs,
 780         .read = seq_read,
 781         .llseek = seq_lseek,
 782         .release = single_release,
 783         .owner = THIS_MODULE,
 784         },
 785         },
 786         {
 787         .name = "state",
 788         .mode = S_IRUGO,
 789         .ops = {
 790         .open = acpi_battery_state_open_fs,
 791         .read = seq_read,
 792         .llseek = seq_lseek,
 793         .release = single_release,
 794         .owner = THIS_MODULE,
 795         },
 796         },
 797         {
 798         .name = "alarm",
 799         .mode = S_IFREG | S_IRUGO | S_IWUSR,
 800         .ops = {
 801         .open = acpi_battery_alarm_open_fs,
 802         .read = seq_read,
 803         .write = acpi_battery_write_alarm,
 804         .llseek = seq_lseek,
 805         .release = single_release,
 806         .owner = THIS_MODULE,
 807         },
 808         },
 809 };
 810
 811 static int acpi_battery_add_fs(struct acpi_device *device)
 812 {
 813         struct proc_dir_entry *entry = NULL;
 814         int i;
 815
 816         if (!acpi_device_dir(device)) {
 817                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 818                                                      acpi_battery_dir);
 819                 if (!acpi_device_dir(device))
 820                         return -ENODEV;
 821                 acpi_device_dir(device)->owner = THIS_MODULE;
 822         }
 823
 824         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i) {
 825                 entry = create_proc_entry(acpi_battery_file[i].name,
 826                                   acpi_battery_file[i].mode, acpi_device_dir(device));
 827                 if (!entry)
 828                         return -ENODEV;
 829                 else {
 830                         entry->proc_fops = &acpi_battery_file[i].ops;
 831                         entry->data = acpi_driver_data(device);
 832                         entry->owner = THIS_MODULE;
 833                 }
 834         }
 835
 836         return 0;
 837 }
 838
 839 static int acpi_battery_remove_fs(struct acpi_device *device)
 840 {
 841         int i;
 842         if (acpi_device_dir(device)) {
 843                 for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i) {
 844                         remove_proc_entry(acpi_battery_file[i].name,
 845                                   acpi_device_dir(device));
 846                 }
 847                 remove_proc_entry(acpi_device_bid(device), acpi_battery_dir);
 848                 acpi_device_dir(device) = NULL;
 849         }
 850
 851         return 0;
 852 }
 853
 854 /* --------------------------------------------------------------------------
 855                                  Driver Interface
 856    -------------------------------------------------------------------------- */
 857
 858 static void acpi_battery_notify(acpi_handle handle, u32 event, void *data)
 859 {
 860         struct acpi_battery *battery = data;
 861         struct acpi_device *device = NULL;
 862
 863         if (!battery)
 864                 return;
 865
 866         device = battery->device;
 867
 868         switch (event) {
 869         case ACPI_BATTERY_NOTIFY_STATUS:
 870         case ACPI_BATTERY_NOTIFY_INFO:
 871         case ACPI_NOTIFY_BUS_CHECK:
 872         case ACPI_NOTIFY_DEVICE_CHECK:
 873                 device = battery->device;
 874                 acpi_battery_notify_update(battery);
 875                 acpi_bus_generate_event(device, event,
 876                                         acpi_battery_present(battery));
 877                 break;
 878         default:
 879                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 880                                   "Unsupported event [0x%x]\n", event));
 881                 break;
 882         }
 883
 884         return;
 885 }
 886
 887 static int acpi_battery_add(struct acpi_device *device)
 888 {
 889         int result = 0;
 890         acpi_status status = 0;
 891         struct acpi_battery *battery = NULL;
 892
 893         if (!device)
 894                 return -EINVAL;
 895
 896         battery = kzalloc(sizeof(struct acpi_battery), GFP_KERNEL);
 897         if (!battery)
 898                 return -ENOMEM;
 899
 900         mutex_init(&battery->mutex);
 901
 902         mutex_lock(&battery->mutex);
 903
 904         battery->device = device;
 905         strcpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
 906         strcpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
 907         acpi_driver_data(device) = battery;
 908
 909         result = acpi_battery_get_status(battery);
 910         if (result)
 911                 goto end;
 912
 913         battery->flags.init_update = 1;
 914
 915         result = acpi_battery_add_fs(device);
 916         if (result)
 917                 goto end;
 918
 919         status = acpi_install_notify_handler(device->handle,
 920                                              ACPI_ALL_NOTIFY,
 921                                              acpi_battery_notify, battery);
 922         if (ACPI_FAILURE(status)) {
 923                 ACPI_EXCEPTION((AE_INFO, status, "Installing notify handler"));
 924                 result = -ENODEV;
 925                 goto end;
 926         }
 927
 928         printk(KERN_INFO PREFIX "%s Slot [%s] (battery %s)\n",
 929                ACPI_BATTERY_DEVICE_NAME, acpi_device_bid(device),
 930                device->status.battery_present ? "present" : "absent");
 931
 932       end:
 933
 934         if (result) {
 935                 acpi_battery_remove_fs(device);
 936                 kfree(battery);
 937         }
 938
 939         mutex_unlock(&battery->mutex);
 940
 941         return result;
 942 }
 943
 944 static int acpi_battery_remove(struct acpi_device *device, int type)
 945 {
 946         acpi_status status = 0;
 947         struct acpi_battery *battery = NULL;
 948
 949         if (!device || !acpi_driver_data(device))
 950                 return -EINVAL;
 951
 952         battery = acpi_driver_data(device);
 953
 954         mutex_lock(&battery->mutex);
 955
 956         status = acpi_remove_notify_handler(device->handle,
 957                                             ACPI_ALL_NOTIFY,
 958                                             acpi_battery_notify);
 959
 960         acpi_battery_remove_fs(device);
 961
 962         kfree(battery->bif_data.pointer);
 963
 964         kfree(battery->bst_data.pointer);
 965
 966         mutex_unlock(&battery->mutex);
 967
 968         mutex_destroy(&battery->mutex);
 969
 970         kfree(battery);
 971
 972         return 0;
 973 }
 974
 975 /* this is needed to learn about changes made in suspended state */
 976 static int acpi_battery_resume(struct acpi_device *device)
 977 {
 978         struct acpi_battery *battery;
 979
 980         if (!device)
 981                 return -EINVAL;
 982
 983         battery = device->driver_data;
 984
 985         battery->flags.init_update = 1;
 986
 987         return 0;
 988 }
 989
 990 static int __init acpi_battery_init(void)
 991 {
 992         int result;
 993
 994         if (acpi_disabled)
 995                 return -ENODEV;
 996
 997         acpi_battery_dir = acpi_lock_battery_dir();
 998         if (!acpi_battery_dir)
 999                 return -ENODEV;
1000
1001         result = acpi_bus_register_driver(&acpi_battery_driver);
1002         if (result < 0) {
1003                 acpi_unlock_battery_dir(acpi_battery_dir);
1004                 return -ENODEV;
1005         }
1006
1007         return 0;
1008 }
1009
1010 static void __exit acpi_battery_exit(void)
1011 {
1012         acpi_bus_unregister_driver(&acpi_battery_driver);
1013
1014         acpi_unlock_battery_dir(acpi_battery_dir);
1015
1016         return;
1017 }
1018
1019 module_init(acpi_battery_init);
1020 module_exit(acpi_battery_exit);