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