drivers/acpi/battery.c

   1 /*
   2  *  battery.c - ACPI Battery Driver (Revision: 2.0)
   3  *
   4  *  Copyright (C) 2007 Alexey Starikovskiy <astarikovskiy@suse.de>
   5  *  Copyright (C) 2004-2007 Vladimir Lebedev <vladimir.p.lebedev@intel.com>
   6  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   7  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   8  *
   9  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  10  *
  11  *  This program is free software; you can redistribute it and/or modify
  12  *  it under the terms of the GNU General Public License as published by
  13  *  the Free Software Foundation; either version 2 of the License, or (at
  14  *  your option) any later version.
  15  *
  16  *  This program is distributed in the hope that it will be useful, but
  17  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  18  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19  *  General Public License for more details.
  20  *
  21  *  You should have received a copy of the GNU General Public License along
  22  *  with this program; if not, write to the Free Software Foundation, Inc.,
  23  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  24  *
  25  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  26  */
  27
  28 #include <linux/kernel.h>
  29 #include <linux/module.h>
  30 #include <linux/init.h>
  31 #include <linux/types.h>
  32 #include <linux/jiffies.h>
  33
  34 #ifdef CONFIG_ACPI_PROCFS_POWER
  35 #include <linux/proc_fs.h>
  36 #include <linux/seq_file.h>
  37 #include <asm/uaccess.h>
  38 #endif
  39
  40 #include <acpi/acpi_bus.h>
  41 #include <acpi/acpi_drivers.h>
  42
  43 #ifdef CONFIG_ACPI_SYSFS_POWER
  44 #include <linux/power_supply.h>
  45 #endif
  46
  47 #define ACPI_BATTERY_VALUE_UNKNOWN 0xFFFFFFFF
  48
  49 #define ACPI_BATTERY_COMPONENT          0x00040000
  50 #define ACPI_BATTERY_CLASS              "battery"
  51 #define ACPI_BATTERY_DEVICE_NAME        "Battery"
  52 #define ACPI_BATTERY_NOTIFY_STATUS      0x80
  53 #define ACPI_BATTERY_NOTIFY_INFO        0x81
  54
  55 #define _COMPONENT              ACPI_BATTERY_COMPONENT
  56
  57 ACPI_MODULE_NAME("battery");
  58
  59 MODULE_AUTHOR("Paul Diefenbaugh");
  60 MODULE_AUTHOR("Alexey Starikovskiy <astarikovskiy@suse.de>");
  61 MODULE_DESCRIPTION("ACPI Battery Driver");
  62 MODULE_LICENSE("GPL");
  63
  64 static unsigned int cache_time = 1000;
  65 module_param(cache_time, uint, 0644);
  66 MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
  67
  68 #ifdef CONFIG_ACPI_PROCFS_POWER
  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 enum acpi_battery_files {
  73         info_tag = 0,
  74         state_tag,
  75         alarm_tag,
  76         ACPI_BATTERY_NUMFILES,
  77 };
  78
  79 #endif
  80
  81 static const struct acpi_device_id battery_device_ids[] = {
  82         {"PNP0C0A", 0},
  83         {"", 0},
  84 };
  85
  86 MODULE_DEVICE_TABLE(acpi, battery_device_ids);
  87
  88
  89 struct acpi_battery {
  90         struct mutex lock;
  91 #ifdef CONFIG_ACPI_SYSFS_POWER
  92         struct power_supply bat;
  93 #endif
  94         struct acpi_device *device;
  95         unsigned long update_time;
  96         int current_now;
  97         int capacity_now;
  98         int voltage_now;
  99         int design_capacity;
 100         int full_charge_capacity;
 101         int technology;
 102         int design_voltage;
 103         int design_capacity_warning;
 104         int design_capacity_low;
 105         int capacity_granularity_1;
 106         int capacity_granularity_2;
 107         int alarm;
 108         char model_number[32];
 109         char serial_number[32];
 110         char type[32];
 111         char oem_info[32];
 112         int state;
 113         int power_unit;
 114         u8 alarm_present;
 115 };
 116
 117 #define to_acpi_battery(x) container_of(x, struct acpi_battery, bat);
 118
 119 inline int acpi_battery_present(struct acpi_battery *battery)
 120 {
 121         return battery->device->status.battery_present;
 122 }
 123
 124 #ifdef CONFIG_ACPI_SYSFS_POWER
 125 static int acpi_battery_technology(struct acpi_battery *battery)
 126 {
 127         if (!strcasecmp("NiCd", battery->type))
 128                 return POWER_SUPPLY_TECHNOLOGY_NiCd;
 129         if (!strcasecmp("NiMH", battery->type))
 130                 return POWER_SUPPLY_TECHNOLOGY_NiMH;
 131         if (!strcasecmp("LION", battery->type))
 132                 return POWER_SUPPLY_TECHNOLOGY_LION;
 133         if (!strncasecmp("LI-ION", battery->type, 6))
 134                 return POWER_SUPPLY_TECHNOLOGY_LION;
 135         if (!strcasecmp("LiP", battery->type))
 136                 return POWER_SUPPLY_TECHNOLOGY_LIPO;
 137         return POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
 138 }
 139
 140 static int acpi_battery_get_state(struct acpi_battery *battery);
 141
 142 static int acpi_battery_get_property(struct power_supply *psy,
 143                                      enum power_supply_property psp,
 144                                      union power_supply_propval *val)
 145 {
 146         struct acpi_battery *battery = to_acpi_battery(psy);
 147
 148         if (acpi_battery_present(battery)) {
 149                 /* run battery update only if it is present */
 150                 acpi_battery_get_state(battery);
 151         } else if (psp != POWER_SUPPLY_PROP_PRESENT)
 152                 return -ENODEV;
 153         switch (psp) {
 154         case POWER_SUPPLY_PROP_STATUS:
 155                 if (battery->state & 0x01)
 156                         val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
 157                 else if (battery->state & 0x02)
 158                         val->intval = POWER_SUPPLY_STATUS_CHARGING;
 159                 else if (battery->state == 0)
 160                         val->intval = POWER_SUPPLY_STATUS_FULL;
 161                 else
 162                         val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
 163                 break;
 164         case POWER_SUPPLY_PROP_PRESENT:
 165                 val->intval = acpi_battery_present(battery);
 166                 break;
 167         case POWER_SUPPLY_PROP_TECHNOLOGY:
 168                 val->intval = acpi_battery_technology(battery);
 169                 break;
 170         case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
 171                 val->intval = battery->design_voltage * 1000;
 172                 break;
 173         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 174                 val->intval = battery->voltage_now * 1000;
 175                 break;
 176         case POWER_SUPPLY_PROP_CURRENT_NOW:
 177                 val->intval = battery->current_now * 1000;
 178                 break;
 179         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
 180         case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
 181                 val->intval = battery->design_capacity * 1000;
 182                 break;
 183         case POWER_SUPPLY_PROP_CHARGE_FULL:
 184         case POWER_SUPPLY_PROP_ENERGY_FULL:
 185                 val->intval = battery->full_charge_capacity * 1000;
 186                 break;
 187         case POWER_SUPPLY_PROP_CHARGE_NOW:
 188         case POWER_SUPPLY_PROP_ENERGY_NOW:
 189                 val->intval = battery->capacity_now * 1000;
 190                 break;
 191         case POWER_SUPPLY_PROP_MODEL_NAME:
 192                 val->strval = battery->model_number;
 193                 break;
 194         case POWER_SUPPLY_PROP_MANUFACTURER:
 195                 val->strval = battery->oem_info;
 196                 break;
 197         case POWER_SUPPLY_PROP_SERIAL_NUMBER:
 198                 val->strval = battery->serial_number;
 199                 break;
 200         default:
 201                 return -EINVAL;
 202         }
 203         return 0;
 204 }
 205
 206 static enum power_supply_property charge_battery_props[] = {
 207         POWER_SUPPLY_PROP_STATUS,
 208         POWER_SUPPLY_PROP_PRESENT,
 209         POWER_SUPPLY_PROP_TECHNOLOGY,
 210         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 211         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 212         POWER_SUPPLY_PROP_CURRENT_NOW,
 213         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 214         POWER_SUPPLY_PROP_CHARGE_FULL,
 215         POWER_SUPPLY_PROP_CHARGE_NOW,
 216         POWER_SUPPLY_PROP_MODEL_NAME,
 217         POWER_SUPPLY_PROP_MANUFACTURER,
 218         POWER_SUPPLY_PROP_SERIAL_NUMBER,
 219 };
 220
 221 static enum power_supply_property energy_battery_props[] = {
 222         POWER_SUPPLY_PROP_STATUS,
 223         POWER_SUPPLY_PROP_PRESENT,
 224         POWER_SUPPLY_PROP_TECHNOLOGY,
 225         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 226         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 227         POWER_SUPPLY_PROP_CURRENT_NOW,
 228         POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
 229         POWER_SUPPLY_PROP_ENERGY_FULL,
 230         POWER_SUPPLY_PROP_ENERGY_NOW,
 231         POWER_SUPPLY_PROP_MODEL_NAME,
 232         POWER_SUPPLY_PROP_MANUFACTURER,
 233         POWER_SUPPLY_PROP_SERIAL_NUMBER,
 234 };
 235 #endif
 236
 237 #ifdef CONFIG_ACPI_PROCFS_POWER
 238 inline char *acpi_battery_units(struct acpi_battery *battery)
 239 {
 240         return (battery->power_unit)?"mA":"mW";
 241 }
 242 #endif
 243
 244 /* --------------------------------------------------------------------------
 245                                Battery Management
 246    -------------------------------------------------------------------------- */
 247 struct acpi_offsets {
 248         size_t offset;          /* offset inside struct acpi_sbs_battery */
 249         u8 mode;                /* int or string? */
 250 };
 251
 252 static struct acpi_offsets state_offsets[] = {
 253         {offsetof(struct acpi_battery, state), 0},
 254         {offsetof(struct acpi_battery, current_now), 0},
 255         {offsetof(struct acpi_battery, capacity_now), 0},
 256         {offsetof(struct acpi_battery, voltage_now), 0},
 257 };
 258
 259 static struct acpi_offsets info_offsets[] = {
 260         {offsetof(struct acpi_battery, power_unit), 0},
 261         {offsetof(struct acpi_battery, design_capacity), 0},
 262         {offsetof(struct acpi_battery, full_charge_capacity), 0},
 263         {offsetof(struct acpi_battery, technology), 0},
 264         {offsetof(struct acpi_battery, design_voltage), 0},
 265         {offsetof(struct acpi_battery, design_capacity_warning), 0},
 266         {offsetof(struct acpi_battery, design_capacity_low), 0},
 267         {offsetof(struct acpi_battery, capacity_granularity_1), 0},
 268         {offsetof(struct acpi_battery, capacity_granularity_2), 0},
 269         {offsetof(struct acpi_battery, model_number), 1},
 270         {offsetof(struct acpi_battery, serial_number), 1},
 271         {offsetof(struct acpi_battery, type), 1},
 272         {offsetof(struct acpi_battery, oem_info), 1},
 273 };
 274
 275 static int extract_package(struct acpi_battery *battery,
 276                            union acpi_object *package,
 277                            struct acpi_offsets *offsets, int num)
 278 {
 279         int i;
 280         union acpi_object *element;
 281         if (package->type != ACPI_TYPE_PACKAGE)
 282                 return -EFAULT;
 283         for (i = 0; i < num; ++i) {
 284                 if (package->package.count <= i)
 285                         return -EFAULT;
 286                 element = &package->package.elements[i];
 287                 if (offsets[i].mode) {
 288                         u8 *ptr = (u8 *)battery + offsets[i].offset;
 289                         if (element->type == ACPI_TYPE_STRING ||
 290                             element->type == ACPI_TYPE_BUFFER)
 291                                 strncpy(ptr, element->string.pointer, 32);
 292                         else if (element->type == ACPI_TYPE_INTEGER) {
 293                                 strncpy(ptr, (u8 *)&element->integer.value,
 294                                         sizeof(acpi_integer));
 295                                 ptr[sizeof(acpi_integer)] = 0;
 296                         } else return -EFAULT;
 297                 } else {
 298                         if (element->type == ACPI_TYPE_INTEGER) {
 299                                 int *x = (int *)((u8 *)battery +
 300                                                 offsets[i].offset);
 301                                 *x = element->integer.value;
 302                         } else return -EFAULT;
 303                 }
 304         }
 305         return 0;
 306 }
 307
 308 static int acpi_battery_get_status(struct acpi_battery *battery)
 309 {
 310         if (acpi_bus_get_status(battery->device)) {
 311                 ACPI_EXCEPTION((AE_INFO, AE_ERROR, "Evaluating _STA"));
 312                 return -ENODEV;
 313         }
 314         return 0;
 315 }
 316
 317 static int acpi_battery_get_info(struct acpi_battery *battery)
 318 {
 319         int result = -EFAULT;
 320         acpi_status status = 0;
 321         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 322
 323         if (!acpi_battery_present(battery))
 324                 return 0;
 325         mutex_lock(&battery->lock);
 326         status = acpi_evaluate_object(battery->device->handle, "_BIF",
 327                                       NULL, &buffer);
 328         mutex_unlock(&battery->lock);
 329
 330         if (ACPI_FAILURE(status)) {
 331                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BIF"));
 332                 return -ENODEV;
 333         }
 334
 335         result = extract_package(battery, buffer.pointer,
 336                                  info_offsets, ARRAY_SIZE(info_offsets));
 337         kfree(buffer.pointer);
 338         return result;
 339 }
 340
 341 static int acpi_battery_get_state(struct acpi_battery *battery)
 342 {
 343         int result = 0;
 344         acpi_status status = 0;
 345         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 346
 347         if (!acpi_battery_present(battery))
 348                 return 0;
 349
 350         if (battery->update_time &&
 351             time_before(jiffies, battery->update_time +
 352                         msecs_to_jiffies(cache_time)))
 353                 return 0;
 354
 355         mutex_lock(&battery->lock);
 356         status = acpi_evaluate_object(battery->device->handle, "_BST",
 357                                       NULL, &buffer);
 358         mutex_unlock(&battery->lock);
 359
 360         if (ACPI_FAILURE(status)) {
 361                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BST"));
 362                 return -ENODEV;
 363         }
 364
 365         result = extract_package(battery, buffer.pointer,
 366                                  state_offsets, ARRAY_SIZE(state_offsets));
 367         battery->update_time = jiffies;
 368         kfree(buffer.pointer);
 369         return result;
 370 }
 371
 372 static int acpi_battery_set_alarm(struct acpi_battery *battery)
 373 {
 374         acpi_status status = 0;
 375         union acpi_object arg0 = { .type = ACPI_TYPE_INTEGER };
 376         struct acpi_object_list arg_list = { 1, &arg0 };
 377
 378         if (!acpi_battery_present(battery)|| !battery->alarm_present)
 379                 return -ENODEV;
 380
 381         arg0.integer.value = battery->alarm;
 382
 383         mutex_lock(&battery->lock);
 384         status = acpi_evaluate_object(battery->device->handle, "_BTP",
 385                                  &arg_list, NULL);
 386         mutex_unlock(&battery->lock);
 387
 388         if (ACPI_FAILURE(status))
 389                 return -ENODEV;
 390
 391         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Alarm set to %d\n", battery->alarm));
 392         return 0;
 393 }
 394
 395 static int acpi_battery_init_alarm(struct acpi_battery *battery)
 396 {
 397         acpi_status status = AE_OK;
 398         acpi_handle handle = NULL;
 399
 400         /* See if alarms are supported, and if so, set default */
 401         status = acpi_get_handle(battery->device->handle, "_BTP", &handle);
 402         if (ACPI_FAILURE(status)) {
 403                 battery->alarm_present = 0;
 404                 return 0;
 405         }
 406         battery->alarm_present = 1;
 407         if (!battery->alarm)
 408                 battery->alarm = battery->design_capacity_warning;
 409         return acpi_battery_set_alarm(battery);
 410 }
 411
 412 #ifdef CONFIG_ACPI_SYSFS_POWER
 413 static ssize_t acpi_battery_alarm_show(struct device *dev,
 414                                         struct device_attribute *attr,
 415                                         char *buf)
 416 {
 417         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
 418         return sprintf(buf, "%d\n", battery->alarm * 1000);
 419 }
 420
 421 static ssize_t acpi_battery_alarm_store(struct device *dev,
 422                                         struct device_attribute *attr,
 423                                         const char *buf, size_t count)
 424 {
 425         unsigned long x;
 426         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
 427         if (sscanf(buf, "%ld\n", &x) == 1)
 428                 battery->alarm = x/1000;
 429         if (acpi_battery_present(battery))
 430                 acpi_battery_set_alarm(battery);
 431         return count;
 432 }
 433
 434 static struct device_attribute alarm_attr = {
 435         .attr = {.name = "alarm", .mode = 0644, .owner = THIS_MODULE},
 436         .show = acpi_battery_alarm_show,
 437         .store = acpi_battery_alarm_store,
 438 };
 439
 440 static int sysfs_add_battery(struct acpi_battery *battery)
 441 {
 442         int result;
 443
 444         if (battery->power_unit) {
 445                 battery->bat.properties = charge_battery_props;
 446                 battery->bat.num_properties =
 447                         ARRAY_SIZE(charge_battery_props);
 448         } else {
 449                 battery->bat.properties = energy_battery_props;
 450                 battery->bat.num_properties =
 451                         ARRAY_SIZE(energy_battery_props);
 452         }
 453
 454         battery->bat.name = acpi_device_bid(battery->device);
 455         battery->bat.type = POWER_SUPPLY_TYPE_BATTERY;
 456         battery->bat.get_property = acpi_battery_get_property;
 457
 458         result = power_supply_register(&battery->device->dev, &battery->bat);
 459         if (result)
 460                 return result;
 461         return device_create_file(battery->bat.dev, &alarm_attr);
 462 }
 463
 464 static void sysfs_remove_battery(struct acpi_battery *battery)
 465 {
 466         if (!battery->bat.dev)
 467                 return;
 468         device_remove_file(battery->bat.dev, &alarm_attr);
 469         power_supply_unregister(&battery->bat);
 470         battery->bat.dev = NULL;
 471 }
 472 #endif
 473
 474 static int acpi_battery_update(struct acpi_battery *battery)
 475 {
 476         int result;
 477         result = acpi_battery_get_status(battery);
 478         if (result)
 479                 return result;
 480 #ifdef CONFIG_ACPI_SYSFS_POWER
 481         if (!acpi_battery_present(battery)) {
 482                 sysfs_remove_battery(battery);
 483                 battery->update_time = 0;
 484                 return 0;
 485         }
 486 #endif
 487         if (!battery->update_time) {
 488                 result = acpi_battery_get_info(battery);
 489                 if (result)
 490                         return result;
 491                 acpi_battery_init_alarm(battery);
 492         }
 493 #ifdef CONFIG_ACPI_SYSFS_POWER
 494         if (!battery->bat.dev)
 495                 sysfs_add_battery(battery);
 496 #endif
 497         return acpi_battery_get_state(battery);
 498 }
 499
 500 /* --------------------------------------------------------------------------
 501                               FS Interface (/proc)
 502    -------------------------------------------------------------------------- */
 503
 504 #ifdef CONFIG_ACPI_PROCFS_POWER
 505 static struct proc_dir_entry *acpi_battery_dir;
 506
 507 static int acpi_battery_print_info(struct seq_file *seq, int result)
 508 {
 509         struct acpi_battery *battery = seq->private;
 510
 511         if (result)
 512                 goto end;
 513
 514         seq_printf(seq, "present:                 %s\n",
 515                    acpi_battery_present(battery)?"yes":"no");
 516         if (!acpi_battery_present(battery))
 517                 goto end;
 518         if (battery->design_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
 519                 seq_printf(seq, "design capacity:         unknown\n");
 520         else
 521                 seq_printf(seq, "design capacity:         %d %sh\n",
 522                            battery->design_capacity,
 523                            acpi_battery_units(battery));
 524
 525         if (battery->full_charge_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
 526                 seq_printf(seq, "last full capacity:      unknown\n");
 527         else
 528                 seq_printf(seq, "last full capacity:      %d %sh\n",
 529                            battery->full_charge_capacity,
 530                            acpi_battery_units(battery));
 531
 532         seq_printf(seq, "battery technology:      %srechargeable\n",
 533                    (!battery->technology)?"non-":"");
 534
 535         if (battery->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
 536                 seq_printf(seq, "design voltage:          unknown\n");
 537         else
 538                 seq_printf(seq, "design voltage:          %d mV\n",
 539                            battery->design_voltage);
 540         seq_printf(seq, "design capacity warning: %d %sh\n",
 541                    battery->design_capacity_warning,
 542                    acpi_battery_units(battery));
 543         seq_printf(seq, "design capacity low:     %d %sh\n",
 544                    battery->design_capacity_low,
 545                    acpi_battery_units(battery));
 546         seq_printf(seq, "capacity granularity 1:  %d %sh\n",
 547                    battery->capacity_granularity_1,
 548                    acpi_battery_units(battery));
 549         seq_printf(seq, "capacity granularity 2:  %d %sh\n",
 550                    battery->capacity_granularity_2,
 551                    acpi_battery_units(battery));
 552         seq_printf(seq, "model number:            %s\n", battery->model_number);
 553         seq_printf(seq, "serial number:           %s\n", battery->serial_number);
 554         seq_printf(seq, "battery type:            %s\n", battery->type);
 555         seq_printf(seq, "OEM info:                %s\n", battery->oem_info);
 556       end:
 557         if (result)
 558                 seq_printf(seq, "ERROR: Unable to read battery info\n");
 559         return result;
 560 }
 561
 562 static int acpi_battery_print_state(struct seq_file *seq, int result)
 563 {
 564         struct acpi_battery *battery = seq->private;
 565
 566         if (result)
 567                 goto end;
 568
 569         seq_printf(seq, "present:                 %s\n",
 570                    acpi_battery_present(battery)?"yes":"no");
 571         if (!acpi_battery_present(battery))
 572                 goto end;
 573
 574         seq_printf(seq, "capacity state:          %s\n",
 575                         (battery->state & 0x04)?"critical":"ok");
 576         if ((battery->state & 0x01) && (battery->state & 0x02))
 577                 seq_printf(seq,
 578                            "charging state:          charging/discharging\n");
 579         else if (battery->state & 0x01)
 580                 seq_printf(seq, "charging state:          discharging\n");
 581         else if (battery->state & 0x02)
 582                 seq_printf(seq, "charging state:          charging\n");
 583         else
 584                 seq_printf(seq, "charging state:          charged\n");
 585
 586         if (battery->current_now == ACPI_BATTERY_VALUE_UNKNOWN)
 587                 seq_printf(seq, "present rate:            unknown\n");
 588         else
 589                 seq_printf(seq, "present rate:            %d %s\n",
 590                            battery->current_now, acpi_battery_units(battery));
 591
 592         if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN)
 593                 seq_printf(seq, "remaining capacity:      unknown\n");
 594         else
 595                 seq_printf(seq, "remaining capacity:      %d %sh\n",
 596                            battery->capacity_now, acpi_battery_units(battery));
 597         if (battery->voltage_now == ACPI_BATTERY_VALUE_UNKNOWN)
 598                 seq_printf(seq, "present voltage:         unknown\n");
 599         else
 600                 seq_printf(seq, "present voltage:         %d mV\n",
 601                            battery->voltage_now);
 602       end:
 603         if (result)
 604                 seq_printf(seq, "ERROR: Unable to read battery state\n");
 605
 606         return result;
 607 }
 608
 609 static int acpi_battery_print_alarm(struct seq_file *seq, int result)
 610 {
 611         struct acpi_battery *battery = seq->private;
 612
 613         if (result)
 614                 goto end;
 615
 616         if (!acpi_battery_present(battery)) {
 617                 seq_printf(seq, "present:                 no\n");
 618                 goto end;
 619         }
 620         seq_printf(seq, "alarm:                   ");
 621         if (!battery->alarm)
 622                 seq_printf(seq, "unsupported\n");
 623         else
 624                 seq_printf(seq, "%u %sh\n", battery->alarm,
 625                                 acpi_battery_units(battery));
 626       end:
 627         if (result)
 628                 seq_printf(seq, "ERROR: Unable to read battery alarm\n");
 629         return result;
 630 }
 631
 632 static ssize_t acpi_battery_write_alarm(struct file *file,
 633                                         const char __user * buffer,
 634                                         size_t count, loff_t * ppos)
 635 {
 636         int result = 0;
 637         char alarm_string[12] = { '\0' };
 638         struct seq_file *m = file->private_data;
 639         struct acpi_battery *battery = m->private;
 640
 641         if (!battery || (count > sizeof(alarm_string) - 1))
 642                 return -EINVAL;
 643         if (!acpi_battery_present(battery)) {
 644                 result = -ENODEV;
 645                 goto end;
 646         }
 647         if (copy_from_user(alarm_string, buffer, count)) {
 648                 result = -EFAULT;
 649                 goto end;
 650         }
 651         alarm_string[count] = '\0';
 652         battery->alarm = simple_strtol(alarm_string, NULL, 0);
 653         result = acpi_battery_set_alarm(battery);
 654       end:
 655         if (!result)
 656                 return count;
 657         return result;
 658 }
 659
 660 typedef int(*print_func)(struct seq_file *seq, int result);
 661
 662 static print_func acpi_print_funcs[ACPI_BATTERY_NUMFILES] = {
 663         acpi_battery_print_info,
 664         acpi_battery_print_state,
 665         acpi_battery_print_alarm,
 666 };
 667
 668 static int acpi_battery_read(int fid, struct seq_file *seq)
 669 {
 670         struct acpi_battery *battery = seq->private;
 671         int result = acpi_battery_update(battery);
 672         return acpi_print_funcs[fid](seq, result);
 673 }
 674
 675 #define DECLARE_FILE_FUNCTIONS(_name) \
 676 static int acpi_battery_read_##_name(struct seq_file *seq, void *offset) \
 677 { \
 678         return acpi_battery_read(_name##_tag, seq); \
 679 } \
 680 static int acpi_battery_##_name##_open_fs(struct inode *inode, struct file *file) \
 681 { \
 682         return single_open(file, acpi_battery_read_##_name, PDE(inode)->data); \
 683 }
 684
 685 DECLARE_FILE_FUNCTIONS(info);
 686 DECLARE_FILE_FUNCTIONS(state);
 687 DECLARE_FILE_FUNCTIONS(alarm);
 688
 689 #undef DECLARE_FILE_FUNCTIONS
 690
 691 #define FILE_DESCRIPTION_RO(_name) \
 692         { \
 693         .name = __stringify(_name), \
 694         .mode = S_IRUGO, \
 695         .ops = { \
 696                 .open = acpi_battery_##_name##_open_fs, \
 697                 .read = seq_read, \
 698                 .llseek = seq_lseek, \
 699                 .release = single_release, \
 700                 .owner = THIS_MODULE, \
 701                 }, \
 702         }
 703
 704 #define FILE_DESCRIPTION_RW(_name) \
 705         { \
 706         .name = __stringify(_name), \
 707         .mode = S_IFREG | S_IRUGO | S_IWUSR, \
 708         .ops = { \
 709                 .open = acpi_battery_##_name##_open_fs, \
 710                 .read = seq_read, \
 711                 .llseek = seq_lseek, \
 712                 .write = acpi_battery_write_##_name, \
 713                 .release = single_release, \
 714                 .owner = THIS_MODULE, \
 715                 }, \
 716         }
 717
 718 static struct battery_file {
 719         struct file_operations ops;
 720         mode_t mode;
 721         char *name;
 722 } acpi_battery_file[] = {
 723         FILE_DESCRIPTION_RO(info),
 724         FILE_DESCRIPTION_RO(state),
 725         FILE_DESCRIPTION_RW(alarm),
 726 };
 727
 728 #undef FILE_DESCRIPTION_RO
 729 #undef FILE_DESCRIPTION_RW
 730
 731 static int acpi_battery_add_fs(struct acpi_device *device)
 732 {
 733         struct proc_dir_entry *entry = NULL;
 734         int i;
 735
 736         if (!acpi_device_dir(device)) {
 737                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 738                                                      acpi_battery_dir);
 739                 if (!acpi_device_dir(device))
 740                         return -ENODEV;
 741                 acpi_device_dir(device)->owner = THIS_MODULE;
 742         }
 743
 744         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i) {
 745                 entry = create_proc_entry(acpi_battery_file[i].name,
 746                                   acpi_battery_file[i].mode, acpi_device_dir(device));
 747                 if (!entry)
 748                         return -ENODEV;
 749                 else {
 750                         entry->proc_fops = &acpi_battery_file[i].ops;
 751                         entry->data = acpi_driver_data(device);
 752                         entry->owner = THIS_MODULE;
 753                 }
 754         }
 755         return 0;
 756 }
 757
 758 static void acpi_battery_remove_fs(struct acpi_device *device)
 759 {
 760         int i;
 761         if (!acpi_device_dir(device))
 762                 return;
 763         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i)
 764                 remove_proc_entry(acpi_battery_file[i].name,
 765                                   acpi_device_dir(device));
 766
 767         remove_proc_entry(acpi_device_bid(device), acpi_battery_dir);
 768         acpi_device_dir(device) = NULL;
 769 }
 770
 771 #endif
 772
 773 /* --------------------------------------------------------------------------
 774                                  Driver Interface
 775    -------------------------------------------------------------------------- */
 776
 777 static void acpi_battery_notify(acpi_handle handle, u32 event, void *data)
 778 {
 779         struct acpi_battery *battery = data;
 780         struct acpi_device *device;
 781         if (!battery)
 782                 return;
 783         device = battery->device;
 784         acpi_battery_update(battery);
 785         acpi_bus_generate_proc_event(device, event,
 786                                      acpi_battery_present(battery));
 787         acpi_bus_generate_netlink_event(device->pnp.device_class,
 788                                         device->dev.bus_id, event,
 789                                         acpi_battery_present(battery));
 790 #ifdef CONFIG_ACPI_SYSFS_POWER
 791         /* acpi_batter_update could remove power_supply object */
 792         if (battery->bat.dev)
 793                 kobject_uevent(&battery->bat.dev->kobj, KOBJ_CHANGE);
 794 #endif
 795 }
 796
 797 static int acpi_battery_add(struct acpi_device *device)
 798 {
 799         int result = 0;
 800         acpi_status status = 0;
 801         struct acpi_battery *battery = NULL;
 802         if (!device)
 803                 return -EINVAL;
 804         battery = kzalloc(sizeof(struct acpi_battery), GFP_KERNEL);
 805         if (!battery)
 806                 return -ENOMEM;
 807         battery->device = device;
 808         strcpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
 809         strcpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
 810         acpi_driver_data(device) = battery;
 811         mutex_init(&battery->lock);
 812         acpi_battery_update(battery);
 813 #ifdef CONFIG_ACPI_PROCFS_POWER
 814         result = acpi_battery_add_fs(device);
 815         if (result)
 816                 goto end;
 817 #endif
 818         status = acpi_install_notify_handler(device->handle,
 819                                              ACPI_ALL_NOTIFY,
 820                                              acpi_battery_notify, battery);
 821         if (ACPI_FAILURE(status)) {
 822                 ACPI_EXCEPTION((AE_INFO, status, "Installing notify handler"));
 823                 result = -ENODEV;
 824                 goto end;
 825         }
 826         printk(KERN_INFO PREFIX "%s Slot [%s] (battery %s)\n",
 827                ACPI_BATTERY_DEVICE_NAME, acpi_device_bid(device),
 828                device->status.battery_present ? "present" : "absent");
 829       end:
 830         if (result) {
 831 #ifdef CONFIG_ACPI_PROCFS_POWER
 832                 acpi_battery_remove_fs(device);
 833 #endif
 834                 kfree(battery);
 835         }
 836         return result;
 837 }
 838
 839 static int acpi_battery_remove(struct acpi_device *device, int type)
 840 {
 841         acpi_status status = 0;
 842         struct acpi_battery *battery = NULL;
 843
 844         if (!device || !acpi_driver_data(device))
 845                 return -EINVAL;
 846         battery = acpi_driver_data(device);
 847         status = acpi_remove_notify_handler(device->handle,
 848                                             ACPI_ALL_NOTIFY,
 849                                             acpi_battery_notify);
 850 #ifdef CONFIG_ACPI_PROCFS_POWER
 851         acpi_battery_remove_fs(device);
 852 #endif
 853 #ifdef CONFIG_ACPI_SYSFS_POWER
 854         sysfs_remove_battery(battery);
 855 #endif
 856         mutex_destroy(&battery->lock);
 857         kfree(battery);
 858         return 0;
 859 }
 860
 861 /* this is needed to learn about changes made in suspended state */
 862 static int acpi_battery_resume(struct acpi_device *device)
 863 {
 864         struct acpi_battery *battery;
 865         if (!device)
 866                 return -EINVAL;
 867         battery = acpi_driver_data(device);
 868         battery->update_time = 0;
 869         acpi_battery_update(battery);
 870         return 0;
 871 }
 872
 873 static struct acpi_driver acpi_battery_driver = {
 874         .name = "battery",
 875         .class = ACPI_BATTERY_CLASS,
 876         .ids = battery_device_ids,
 877         .ops = {
 878                 .add = acpi_battery_add,
 879                 .resume = acpi_battery_resume,
 880                 .remove = acpi_battery_remove,
 881                 },
 882 };
 883
 884 static int __init acpi_battery_init(void)
 885 {
 886         if (acpi_disabled)
 887                 return -ENODEV;
 888 #ifdef CONFIG_ACPI_PROCFS_POWER
 889         acpi_battery_dir = acpi_lock_battery_dir();
 890         if (!acpi_battery_dir)
 891                 return -ENODEV;
 892 #endif
 893         if (acpi_bus_register_driver(&acpi_battery_driver) < 0) {
 894 #ifdef CONFIG_ACPI_PROCFS_POWER
 895                 acpi_unlock_battery_dir(acpi_battery_dir);
 896 #endif
 897                 return -ENODEV;
 898         }
 899         return 0;
 900 }
 901
 902 static void __exit acpi_battery_exit(void)
 903 {
 904         acpi_bus_unregister_driver(&acpi_battery_driver);
 905 #ifdef CONFIG_ACPI_PROCFS_POWER
 906         acpi_unlock_battery_dir(acpi_battery_dir);
 907 #endif
 908 }
 909
 910 module_init(acpi_battery_init);
 911 module_exit(acpi_battery_exit);