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 #include <linux/power_supply.h>
  44
  45 #define ACPI_BATTERY_VALUE_UNKNOWN 0xFFFFFFFF
  46
  47 #define ACPI_BATTERY_COMPONENT          0x00040000
  48 #define ACPI_BATTERY_CLASS              "battery"
  49 #define ACPI_BATTERY_DEVICE_NAME        "Battery"
  50 #define ACPI_BATTERY_NOTIFY_STATUS      0x80
  51 #define ACPI_BATTERY_NOTIFY_INFO        0x81
  52
  53 #define _COMPONENT              ACPI_BATTERY_COMPONENT
  54
  55 ACPI_MODULE_NAME("battery");
  56
  57 MODULE_AUTHOR("Paul Diefenbaugh");
  58 MODULE_AUTHOR("Alexey Starikovskiy <astarikovskiy@suse.de>");
  59 MODULE_DESCRIPTION("ACPI Battery Driver");
  60 MODULE_LICENSE("GPL");
  61
  62 static unsigned int cache_time = 1000;
  63 module_param(cache_time, uint, 0644);
  64 MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
  65
  66 #ifdef CONFIG_ACPI_PROCFS_POWER
  67 extern struct proc_dir_entry *acpi_lock_battery_dir(void);
  68 extern void *acpi_unlock_battery_dir(struct proc_dir_entry *acpi_battery_dir);
  69
  70 enum acpi_battery_files {
  71         info_tag = 0,
  72         state_tag,
  73         alarm_tag,
  74         ACPI_BATTERY_NUMFILES,
  75 };
  76
  77 #endif
  78
  79 static const struct acpi_device_id battery_device_ids[] = {
  80         {"PNP0C0A", 0},
  81         {"", 0},
  82 };
  83
  84 MODULE_DEVICE_TABLE(acpi, battery_device_ids);
  85
  86
  87 struct acpi_battery {
  88         struct mutex lock;
  89         struct power_supply bat;
  90         struct acpi_device *device;
  91         unsigned long update_time;
  92         int current_now;
  93         int capacity_now;
  94         int voltage_now;
  95         int design_capacity;
  96         int full_charge_capacity;
  97         int technology;
  98         int design_voltage;
  99         int design_capacity_warning;
 100         int design_capacity_low;
 101         int capacity_granularity_1;
 102         int capacity_granularity_2;
 103         int alarm;
 104         char model_number[32];
 105         char serial_number[32];
 106         char type[32];
 107         char oem_info[32];
 108         int state;
 109         int power_unit;
 110         u8 alarm_present;
 111 };
 112
 113 #define to_acpi_battery(x) container_of(x, struct acpi_battery, bat);
 114
 115 inline int acpi_battery_present(struct acpi_battery *battery)
 116 {
 117         return battery->device->status.battery_present;
 118 }
 119
 120 static int acpi_battery_technology(struct acpi_battery *battery)
 121 {
 122         if (!strcasecmp("NiCd", battery->type))
 123                 return POWER_SUPPLY_TECHNOLOGY_NiCd;
 124         if (!strcasecmp("NiMH", battery->type))
 125                 return POWER_SUPPLY_TECHNOLOGY_NiMH;
 126         if (!strcasecmp("LION", battery->type))
 127                 return POWER_SUPPLY_TECHNOLOGY_LION;
 128         if (!strncasecmp("LI-ION", battery->type, 6))
 129                 return POWER_SUPPLY_TECHNOLOGY_LION;
 130         if (!strcasecmp("LiP", battery->type))
 131                 return POWER_SUPPLY_TECHNOLOGY_LIPO;
 132         return POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
 133 }
 134
 135 static int acpi_battery_get_state(struct acpi_battery *battery);
 136
 137 static int acpi_battery_get_property(struct power_supply *psy,
 138                                      enum power_supply_property psp,
 139                                      union power_supply_propval *val)
 140 {
 141         struct acpi_battery *battery = to_acpi_battery(psy);
 142
 143         if (acpi_battery_present(battery)) {
 144                 /* run battery update only if it is present */
 145                 acpi_battery_get_state(battery);
 146         } else if (psp != POWER_SUPPLY_PROP_PRESENT)
 147                 return -ENODEV;
 148         switch (psp) {
 149         case POWER_SUPPLY_PROP_STATUS:
 150                 if (battery->state & 0x01)
 151                         val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
 152                 else if (battery->state & 0x02)
 153                         val->intval = POWER_SUPPLY_STATUS_CHARGING;
 154                 else if (battery->state == 0)
 155                         val->intval = POWER_SUPPLY_STATUS_FULL;
 156                 else
 157                         val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
 158                 break;
 159         case POWER_SUPPLY_PROP_PRESENT:
 160                 val->intval = acpi_battery_present(battery);
 161                 break;
 162         case POWER_SUPPLY_PROP_TECHNOLOGY:
 163                 val->intval = acpi_battery_technology(battery);
 164                 break;
 165         case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
 166                 val->intval = battery->design_voltage * 1000;
 167                 break;
 168         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 169                 val->intval = battery->voltage_now * 1000;
 170                 break;
 171         case POWER_SUPPLY_PROP_CURRENT_NOW:
 172                 val->intval = battery->current_now * 1000;
 173                 break;
 174         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
 175         case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
 176                 val->intval = battery->design_capacity * 1000;
 177                 break;
 178         case POWER_SUPPLY_PROP_CHARGE_FULL:
 179         case POWER_SUPPLY_PROP_ENERGY_FULL:
 180                 val->intval = battery->full_charge_capacity * 1000;
 181                 break;
 182         case POWER_SUPPLY_PROP_CHARGE_NOW:
 183         case POWER_SUPPLY_PROP_ENERGY_NOW:
 184                 val->intval = battery->capacity_now * 1000;
 185                 break;
 186         case POWER_SUPPLY_PROP_MODEL_NAME:
 187                 val->strval = battery->model_number;
 188                 break;
 189         case POWER_SUPPLY_PROP_MANUFACTURER:
 190                 val->strval = battery->oem_info;
 191                 break;
 192         default:
 193                 return -EINVAL;
 194         }
 195         return 0;
 196 }
 197
 198 static enum power_supply_property charge_battery_props[] = {
 199         POWER_SUPPLY_PROP_STATUS,
 200         POWER_SUPPLY_PROP_PRESENT,
 201         POWER_SUPPLY_PROP_TECHNOLOGY,
 202         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 203         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 204         POWER_SUPPLY_PROP_CURRENT_NOW,
 205         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 206         POWER_SUPPLY_PROP_CHARGE_FULL,
 207         POWER_SUPPLY_PROP_CHARGE_NOW,
 208         POWER_SUPPLY_PROP_MODEL_NAME,
 209         POWER_SUPPLY_PROP_MANUFACTURER,
 210 };
 211
 212 static enum power_supply_property energy_battery_props[] = {
 213         POWER_SUPPLY_PROP_STATUS,
 214         POWER_SUPPLY_PROP_PRESENT,
 215         POWER_SUPPLY_PROP_TECHNOLOGY,
 216         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 217         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 218         POWER_SUPPLY_PROP_CURRENT_NOW,
 219         POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
 220         POWER_SUPPLY_PROP_ENERGY_FULL,
 221         POWER_SUPPLY_PROP_ENERGY_NOW,
 222         POWER_SUPPLY_PROP_MODEL_NAME,
 223         POWER_SUPPLY_PROP_MANUFACTURER,
 224 };
 225
 226 #ifdef CONFIG_ACPI_PROCFS_POWER
 227 inline char *acpi_battery_units(struct acpi_battery *battery)
 228 {
 229         return (battery->power_unit)?"mA":"mW";
 230 }
 231 #endif
 232
 233 /* --------------------------------------------------------------------------
 234                                Battery Management
 235    -------------------------------------------------------------------------- */
 236 struct acpi_offsets {
 237         size_t offset;          /* offset inside struct acpi_sbs_battery */
 238         u8 mode;                /* int or string? */
 239 };
 240
 241 static struct acpi_offsets state_offsets[] = {
 242         {offsetof(struct acpi_battery, state), 0},
 243         {offsetof(struct acpi_battery, current_now), 0},
 244         {offsetof(struct acpi_battery, capacity_now), 0},
 245         {offsetof(struct acpi_battery, voltage_now), 0},
 246 };
 247
 248 static struct acpi_offsets info_offsets[] = {
 249         {offsetof(struct acpi_battery, power_unit), 0},
 250         {offsetof(struct acpi_battery, design_capacity), 0},
 251         {offsetof(struct acpi_battery, full_charge_capacity), 0},
 252         {offsetof(struct acpi_battery, technology), 0},
 253         {offsetof(struct acpi_battery, design_voltage), 0},
 254         {offsetof(struct acpi_battery, design_capacity_warning), 0},
 255         {offsetof(struct acpi_battery, design_capacity_low), 0},
 256         {offsetof(struct acpi_battery, capacity_granularity_1), 0},
 257         {offsetof(struct acpi_battery, capacity_granularity_2), 0},
 258         {offsetof(struct acpi_battery, model_number), 1},
 259         {offsetof(struct acpi_battery, serial_number), 1},
 260         {offsetof(struct acpi_battery, type), 1},
 261         {offsetof(struct acpi_battery, oem_info), 1},
 262 };
 263
 264 static int extract_package(struct acpi_battery *battery,
 265                            union acpi_object *package,
 266                            struct acpi_offsets *offsets, int num)
 267 {
 268         int i;
 269         union acpi_object *element;
 270         if (package->type != ACPI_TYPE_PACKAGE)
 271                 return -EFAULT;
 272         for (i = 0; i < num; ++i) {
 273                 if (package->package.count <= i)
 274                         return -EFAULT;
 275                 element = &package->package.elements[i];
 276                 if (offsets[i].mode) {
 277                         u8 *ptr = (u8 *)battery + offsets[i].offset;
 278                         if (element->type == ACPI_TYPE_STRING ||
 279                             element->type == ACPI_TYPE_BUFFER)
 280                                 strncpy(ptr, element->string.pointer, 32);
 281                         else if (element->type == ACPI_TYPE_INTEGER) {
 282                                 strncpy(ptr, (u8 *)&element->integer.value,
 283                                         sizeof(acpi_integer));
 284                                 ptr[sizeof(acpi_integer)] = 0;
 285                         } else return -EFAULT;
 286                 } else {
 287                         if (element->type == ACPI_TYPE_INTEGER) {
 288                                 int *x = (int *)((u8 *)battery +
 289                                                 offsets[i].offset);
 290                                 *x = element->integer.value;
 291                         } else return -EFAULT;
 292                 }
 293         }
 294         return 0;
 295 }
 296
 297 static int acpi_battery_get_status(struct acpi_battery *battery)
 298 {
 299         if (acpi_bus_get_status(battery->device)) {
 300                 ACPI_EXCEPTION((AE_INFO, AE_ERROR, "Evaluating _STA"));
 301                 return -ENODEV;
 302         }
 303         return 0;
 304 }
 305
 306 static int acpi_battery_get_info(struct acpi_battery *battery)
 307 {
 308         int result = -EFAULT;
 309         acpi_status status = 0;
 310         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 311
 312         if (!acpi_battery_present(battery))
 313                 return 0;
 314         mutex_lock(&battery->lock);
 315         status = acpi_evaluate_object(battery->device->handle, "_BIF",
 316                                       NULL, &buffer);
 317         mutex_unlock(&battery->lock);
 318
 319         if (ACPI_FAILURE(status)) {
 320                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BIF"));
 321                 return -ENODEV;
 322         }
 323
 324         result = extract_package(battery, buffer.pointer,
 325                                  info_offsets, ARRAY_SIZE(info_offsets));
 326         kfree(buffer.pointer);
 327         return result;
 328 }
 329
 330 static int acpi_battery_get_state(struct acpi_battery *battery)
 331 {
 332         int result = 0;
 333         acpi_status status = 0;
 334         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 335
 336         if (!acpi_battery_present(battery))
 337                 return 0;
 338
 339         if (battery->update_time &&
 340             time_before(jiffies, battery->update_time +
 341                         msecs_to_jiffies(cache_time)))
 342                 return 0;
 343
 344         mutex_lock(&battery->lock);
 345         status = acpi_evaluate_object(battery->device->handle, "_BST",
 346                                       NULL, &buffer);
 347         mutex_unlock(&battery->lock);
 348
 349         if (ACPI_FAILURE(status)) {
 350                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BST"));
 351                 return -ENODEV;
 352         }
 353
 354         result = extract_package(battery, buffer.pointer,
 355                                  state_offsets, ARRAY_SIZE(state_offsets));
 356         battery->update_time = jiffies;
 357         kfree(buffer.pointer);
 358         return result;
 359 }
 360
 361 static int acpi_battery_set_alarm(struct acpi_battery *battery)
 362 {
 363         acpi_status status = 0;
 364         union acpi_object arg0 = { .type = ACPI_TYPE_INTEGER };
 365         struct acpi_object_list arg_list = { 1, &arg0 };
 366
 367         if (!acpi_battery_present(battery)|| !battery->alarm_present)
 368                 return -ENODEV;
 369
 370         arg0.integer.value = battery->alarm;
 371
 372         mutex_lock(&battery->lock);
 373         status = acpi_evaluate_object(battery->device->handle, "_BTP",
 374                                  &arg_list, NULL);
 375         mutex_unlock(&battery->lock);
 376
 377         if (ACPI_FAILURE(status))
 378                 return -ENODEV;
 379
 380         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Alarm set to %d\n", battery->alarm));
 381         return 0;
 382 }
 383
 384 static int acpi_battery_init_alarm(struct acpi_battery *battery)
 385 {
 386         acpi_status status = AE_OK;
 387         acpi_handle handle = NULL;
 388
 389         /* See if alarms are supported, and if so, set default */
 390         status = acpi_get_handle(battery->device->handle, "_BTP", &handle);
 391         if (ACPI_FAILURE(status)) {
 392                 battery->alarm_present = 0;
 393                 return 0;
 394         }
 395         battery->alarm_present = 1;
 396         if (!battery->alarm)
 397                 battery->alarm = battery->design_capacity_warning;
 398         return acpi_battery_set_alarm(battery);
 399 }
 400
 401 static ssize_t acpi_battery_alarm_show(struct device *dev,
 402                                         struct device_attribute *attr,
 403                                         char *buf)
 404 {
 405         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
 406         return sprintf(buf, "%d\n", battery->alarm * 1000);
 407 }
 408
 409 static ssize_t acpi_battery_alarm_store(struct device *dev,
 410                                         struct device_attribute *attr,
 411                                         const char *buf, size_t count)
 412 {
 413         unsigned long x;
 414         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
 415         if (sscanf(buf, "%ld\n", &x) == 1)
 416                 battery->alarm = x/1000;
 417         if (acpi_battery_present(battery))
 418                 acpi_battery_set_alarm(battery);
 419         return count;
 420 }
 421
 422 static struct device_attribute alarm_attr = {
 423         .attr = {.name = "alarm", .mode = 0644, .owner = THIS_MODULE},
 424         .show = acpi_battery_alarm_show,
 425         .store = acpi_battery_alarm_store,
 426 };
 427
 428 static int sysfs_add_battery(struct acpi_battery *battery)
 429 {
 430         int result;
 431
 432         battery->update_time = 0;
 433         result = acpi_battery_get_info(battery);
 434         acpi_battery_init_alarm(battery);
 435         if (result)
 436                 return result;
 437         if (battery->power_unit) {
 438                 battery->bat.properties = charge_battery_props;
 439                 battery->bat.num_properties =
 440                         ARRAY_SIZE(charge_battery_props);
 441         } else {
 442                 battery->bat.properties = energy_battery_props;
 443                 battery->bat.num_properties =
 444                         ARRAY_SIZE(energy_battery_props);
 445         }
 446
 447         battery->bat.name = acpi_device_bid(battery->device);
 448         battery->bat.type = POWER_SUPPLY_TYPE_BATTERY;
 449         battery->bat.get_property = acpi_battery_get_property;
 450
 451         result = power_supply_register(&battery->device->dev, &battery->bat);
 452         if (result)
 453                 return result;
 454         return device_create_file(battery->bat.dev, &alarm_attr);
 455 }
 456
 457 static void sysfs_remove_battery(struct acpi_battery *battery)
 458 {
 459         if (!battery->bat.dev)
 460                 return;
 461         device_remove_file(battery->bat.dev, &alarm_attr);
 462         power_supply_unregister(&battery->bat);
 463         battery->bat.dev = NULL;
 464 }
 465
 466 static int acpi_battery_update(struct acpi_battery *battery)
 467 {
 468         int result = acpi_battery_get_status(battery);
 469         if (result)
 470                 return result;
 471         if (!acpi_battery_present(battery)) {
 472                 sysfs_remove_battery(battery);
 473                 return 0;
 474         }
 475         if (!battery->bat.dev)
 476                 sysfs_add_battery(battery);
 477         return acpi_battery_get_state(battery);
 478 }
 479
 480 /* --------------------------------------------------------------------------
 481                               FS Interface (/proc)
 482    -------------------------------------------------------------------------- */
 483
 484 #ifdef CONFIG_ACPI_PROCFS_POWER
 485 static struct proc_dir_entry *acpi_battery_dir;
 486
 487 static int acpi_battery_print_info(struct seq_file *seq, int result)
 488 {
 489         struct acpi_battery *battery = seq->private;
 490
 491         if (result)
 492                 goto end;
 493
 494         seq_printf(seq, "present:                 %s\n",
 495                    acpi_battery_present(battery)?"yes":"no");
 496         if (!acpi_battery_present(battery))
 497                 goto end;
 498         if (battery->design_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
 499                 seq_printf(seq, "design capacity:         unknown\n");
 500         else
 501                 seq_printf(seq, "design capacity:         %d %sh\n",
 502                            battery->design_capacity,
 503                            acpi_battery_units(battery));
 504
 505         if (battery->full_charge_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
 506                 seq_printf(seq, "last full capacity:      unknown\n");
 507         else
 508                 seq_printf(seq, "last full capacity:      %d %sh\n",
 509                            battery->full_charge_capacity,
 510                            acpi_battery_units(battery));
 511
 512         seq_printf(seq, "battery technology:      %srechargeable\n",
 513                    (!battery->technology)?"non-":"");
 514
 515         if (battery->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
 516                 seq_printf(seq, "design voltage:          unknown\n");
 517         else
 518                 seq_printf(seq, "design voltage:          %d mV\n",
 519                            battery->design_voltage);
 520         seq_printf(seq, "design capacity warning: %d %sh\n",
 521                    battery->design_capacity_warning,
 522                    acpi_battery_units(battery));
 523         seq_printf(seq, "design capacity low:     %d %sh\n",
 524                    battery->design_capacity_low,
 525                    acpi_battery_units(battery));
 526         seq_printf(seq, "capacity granularity 1:  %d %sh\n",
 527                    battery->capacity_granularity_1,
 528                    acpi_battery_units(battery));
 529         seq_printf(seq, "capacity granularity 2:  %d %sh\n",
 530                    battery->capacity_granularity_2,
 531                    acpi_battery_units(battery));
 532         seq_printf(seq, "model number:            %s\n", battery->model_number);
 533         seq_printf(seq, "serial number:           %s\n", battery->serial_number);
 534         seq_printf(seq, "battery type:            %s\n", battery->type);
 535         seq_printf(seq, "OEM info:                %s\n", battery->oem_info);
 536       end:
 537         if (result)
 538                 seq_printf(seq, "ERROR: Unable to read battery info\n");
 539         return result;
 540 }
 541
 542 static int acpi_battery_print_state(struct seq_file *seq, int result)
 543 {
 544         struct acpi_battery *battery = seq->private;
 545
 546         if (result)
 547                 goto end;
 548
 549         seq_printf(seq, "present:                 %s\n",
 550                    acpi_battery_present(battery)?"yes":"no");
 551         if (!acpi_battery_present(battery))
 552                 goto end;
 553
 554         seq_printf(seq, "capacity state:          %s\n",
 555                         (battery->state & 0x04)?"critical":"ok");
 556         if ((battery->state & 0x01) && (battery->state & 0x02))
 557                 seq_printf(seq,
 558                            "charging state:          charging/discharging\n");
 559         else if (battery->state & 0x01)
 560                 seq_printf(seq, "charging state:          discharging\n");
 561         else if (battery->state & 0x02)
 562                 seq_printf(seq, "charging state:          charging\n");
 563         else
 564                 seq_printf(seq, "charging state:          charged\n");
 565
 566         if (battery->current_now == ACPI_BATTERY_VALUE_UNKNOWN)
 567                 seq_printf(seq, "present rate:            unknown\n");
 568         else
 569                 seq_printf(seq, "present rate:            %d %s\n",
 570                            battery->current_now, acpi_battery_units(battery));
 571
 572         if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN)
 573                 seq_printf(seq, "remaining capacity:      unknown\n");
 574         else
 575                 seq_printf(seq, "remaining capacity:      %d %sh\n",
 576                            battery->capacity_now, acpi_battery_units(battery));
 577         if (battery->voltage_now == ACPI_BATTERY_VALUE_UNKNOWN)
 578                 seq_printf(seq, "present voltage:         unknown\n");
 579         else
 580                 seq_printf(seq, "present voltage:         %d mV\n",
 581                            battery->voltage_now);
 582       end:
 583         if (result)
 584                 seq_printf(seq, "ERROR: Unable to read battery state\n");
 585
 586         return result;
 587 }
 588
 589 static int acpi_battery_print_alarm(struct seq_file *seq, int result)
 590 {
 591         struct acpi_battery *battery = seq->private;
 592
 593         if (result)
 594                 goto end;
 595
 596         if (!acpi_battery_present(battery)) {
 597                 seq_printf(seq, "present:                 no\n");
 598                 goto end;
 599         }
 600         seq_printf(seq, "alarm:                   ");
 601         if (!battery->alarm)
 602                 seq_printf(seq, "unsupported\n");
 603         else
 604                 seq_printf(seq, "%u %sh\n", battery->alarm,
 605                                 acpi_battery_units(battery));
 606       end:
 607         if (result)
 608                 seq_printf(seq, "ERROR: Unable to read battery alarm\n");
 609         return result;
 610 }
 611
 612 static ssize_t acpi_battery_write_alarm(struct file *file,
 613                                         const char __user * buffer,
 614                                         size_t count, loff_t * ppos)
 615 {
 616         int result = 0;
 617         char alarm_string[12] = { '\0' };
 618         struct seq_file *m = file->private_data;
 619         struct acpi_battery *battery = m->private;
 620
 621         if (!battery || (count > sizeof(alarm_string) - 1))
 622                 return -EINVAL;
 623         if (!acpi_battery_present(battery)) {
 624                 result = -ENODEV;
 625                 goto end;
 626         }
 627         if (copy_from_user(alarm_string, buffer, count)) {
 628                 result = -EFAULT;
 629                 goto end;
 630         }
 631         alarm_string[count] = '\0';
 632         battery->alarm = simple_strtol(alarm_string, NULL, 0);
 633         result = acpi_battery_set_alarm(battery);
 634       end:
 635         if (!result)
 636                 return count;
 637         return result;
 638 }
 639
 640 typedef int(*print_func)(struct seq_file *seq, int result);
 641
 642 static print_func acpi_print_funcs[ACPI_BATTERY_NUMFILES] = {
 643         acpi_battery_print_info,
 644         acpi_battery_print_state,
 645         acpi_battery_print_alarm,
 646 };
 647
 648 static int acpi_battery_read(int fid, struct seq_file *seq)
 649 {
 650         struct acpi_battery *battery = seq->private;
 651         int result = acpi_battery_update(battery);
 652         return acpi_print_funcs[fid](seq, result);
 653 }
 654
 655 #define DECLARE_FILE_FUNCTIONS(_name) \
 656 static int acpi_battery_read_##_name(struct seq_file *seq, void *offset) \
 657 { \
 658         return acpi_battery_read(_name##_tag, seq); \
 659 } \
 660 static int acpi_battery_##_name##_open_fs(struct inode *inode, struct file *file) \
 661 { \
 662         return single_open(file, acpi_battery_read_##_name, PDE(inode)->data); \
 663 }
 664
 665 DECLARE_FILE_FUNCTIONS(info);
 666 DECLARE_FILE_FUNCTIONS(state);
 667 DECLARE_FILE_FUNCTIONS(alarm);
 668
 669 #undef DECLARE_FILE_FUNCTIONS
 670
 671 #define FILE_DESCRIPTION_RO(_name) \
 672         { \
 673         .name = __stringify(_name), \
 674         .mode = S_IRUGO, \
 675         .ops = { \
 676                 .open = acpi_battery_##_name##_open_fs, \
 677                 .read = seq_read, \
 678                 .llseek = seq_lseek, \
 679                 .release = single_release, \
 680                 .owner = THIS_MODULE, \
 681                 }, \
 682         }
 683
 684 #define FILE_DESCRIPTION_RW(_name) \
 685         { \
 686         .name = __stringify(_name), \
 687         .mode = S_IFREG | S_IRUGO | S_IWUSR, \
 688         .ops = { \
 689                 .open = acpi_battery_##_name##_open_fs, \
 690                 .read = seq_read, \
 691                 .llseek = seq_lseek, \
 692                 .write = acpi_battery_write_##_name, \
 693                 .release = single_release, \
 694                 .owner = THIS_MODULE, \
 695                 }, \
 696         }
 697
 698 static struct battery_file {
 699         struct file_operations ops;
 700         mode_t mode;
 701         char *name;
 702 } acpi_battery_file[] = {
 703         FILE_DESCRIPTION_RO(info),
 704         FILE_DESCRIPTION_RO(state),
 705         FILE_DESCRIPTION_RW(alarm),
 706 };
 707
 708 #undef FILE_DESCRIPTION_RO
 709 #undef FILE_DESCRIPTION_RW
 710
 711 static int acpi_battery_add_fs(struct acpi_device *device)
 712 {
 713         struct proc_dir_entry *entry = NULL;
 714         int i;
 715
 716         if (!acpi_device_dir(device)) {
 717                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 718                                                      acpi_battery_dir);
 719                 if (!acpi_device_dir(device))
 720                         return -ENODEV;
 721                 acpi_device_dir(device)->owner = THIS_MODULE;
 722         }
 723
 724         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i) {
 725                 entry = create_proc_entry(acpi_battery_file[i].name,
 726                                   acpi_battery_file[i].mode, acpi_device_dir(device));
 727                 if (!entry)
 728                         return -ENODEV;
 729                 else {
 730                         entry->proc_fops = &acpi_battery_file[i].ops;
 731                         entry->data = acpi_driver_data(device);
 732                         entry->owner = THIS_MODULE;
 733                 }
 734         }
 735         return 0;
 736 }
 737
 738 static void acpi_battery_remove_fs(struct acpi_device *device)
 739 {
 740         int i;
 741         if (!acpi_device_dir(device))
 742                 return;
 743         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i)
 744                 remove_proc_entry(acpi_battery_file[i].name,
 745                                   acpi_device_dir(device));
 746
 747         remove_proc_entry(acpi_device_bid(device), acpi_battery_dir);
 748         acpi_device_dir(device) = NULL;
 749 }
 750
 751 #endif
 752
 753 /* --------------------------------------------------------------------------
 754                                  Driver Interface
 755    -------------------------------------------------------------------------- */
 756
 757 static void acpi_battery_notify(acpi_handle handle, u32 event, void *data)
 758 {
 759         struct acpi_battery *battery = data;
 760         struct acpi_device *device;
 761         if (!battery)
 762                 return;
 763         device = battery->device;
 764         acpi_battery_update(battery);
 765         acpi_bus_generate_proc_event(device, event,
 766                                      acpi_battery_present(battery));
 767         acpi_bus_generate_netlink_event(device->pnp.device_class,
 768                                         device->dev.bus_id, event,
 769                                         acpi_battery_present(battery));
 770         /* acpi_batter_update could remove power_supply object */
 771         if (battery->bat.dev)
 772                 kobject_uevent(&battery->bat.dev->kobj, KOBJ_CHANGE);
 773 }
 774
 775 static int acpi_battery_add(struct acpi_device *device)
 776 {
 777         int result = 0;
 778         acpi_status status = 0;
 779         struct acpi_battery *battery = NULL;
 780         if (!device)
 781                 return -EINVAL;
 782         battery = kzalloc(sizeof(struct acpi_battery), GFP_KERNEL);
 783         if (!battery)
 784                 return -ENOMEM;
 785         battery->device = device;
 786         strcpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
 787         strcpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
 788         acpi_driver_data(device) = battery;
 789         mutex_init(&battery->lock);
 790         acpi_battery_update(battery);
 791 #ifdef CONFIG_ACPI_PROCFS_POWER
 792         result = acpi_battery_add_fs(device);
 793         if (result)
 794                 goto end;
 795 #endif
 796         status = acpi_install_notify_handler(device->handle,
 797                                              ACPI_ALL_NOTIFY,
 798                                              acpi_battery_notify, battery);
 799         if (ACPI_FAILURE(status)) {
 800                 ACPI_EXCEPTION((AE_INFO, status, "Installing notify handler"));
 801                 result = -ENODEV;
 802                 goto end;
 803         }
 804         printk(KERN_INFO PREFIX "%s Slot [%s] (battery %s)\n",
 805                ACPI_BATTERY_DEVICE_NAME, acpi_device_bid(device),
 806                device->status.battery_present ? "present" : "absent");
 807       end:
 808         if (result) {
 809 #ifdef CONFIG_ACPI_PROCFS_POWER
 810                 acpi_battery_remove_fs(device);
 811 #endif
 812                 kfree(battery);
 813         }
 814         return result;
 815 }
 816
 817 static int acpi_battery_remove(struct acpi_device *device, int type)
 818 {
 819         acpi_status status = 0;
 820         struct acpi_battery *battery = NULL;
 821
 822         if (!device || !acpi_driver_data(device))
 823                 return -EINVAL;
 824         battery = acpi_driver_data(device);
 825         status = acpi_remove_notify_handler(device->handle,
 826                                             ACPI_ALL_NOTIFY,
 827                                             acpi_battery_notify);
 828 #ifdef CONFIG_ACPI_PROCFS_POWER
 829         acpi_battery_remove_fs(device);
 830 #endif
 831         sysfs_remove_battery(battery);
 832         mutex_destroy(&battery->lock);
 833         kfree(battery);
 834         return 0;
 835 }
 836
 837 /* this is needed to learn about changes made in suspended state */
 838 static int acpi_battery_resume(struct acpi_device *device)
 839 {
 840         struct acpi_battery *battery;
 841         if (!device)
 842                 return -EINVAL;
 843         battery = acpi_driver_data(device);
 844         battery->update_time = 0;
 845         acpi_battery_update(battery);
 846         return 0;
 847 }
 848
 849 static struct acpi_driver acpi_battery_driver = {
 850         .name = "battery",
 851         .class = ACPI_BATTERY_CLASS,
 852         .ids = battery_device_ids,
 853         .ops = {
 854                 .add = acpi_battery_add,
 855                 .resume = acpi_battery_resume,
 856                 .remove = acpi_battery_remove,
 857                 },
 858 };
 859
 860 static int __init acpi_battery_init(void)
 861 {
 862         if (acpi_disabled)
 863                 return -ENODEV;
 864 #ifdef CONFIG_ACPI_PROCFS_POWER
 865         acpi_battery_dir = acpi_lock_battery_dir();
 866         if (!acpi_battery_dir)
 867                 return -ENODEV;
 868 #endif
 869         if (acpi_bus_register_driver(&acpi_battery_driver) < 0) {
 870 #ifdef CONFIG_ACPI_PROCFS_POWER
 871                 acpi_unlock_battery_dir(acpi_battery_dir);
 872 #endif
 873                 return -ENODEV;
 874         }
 875         return 0;
 876 }
 877
 878 static void __exit acpi_battery_exit(void)
 879 {
 880         acpi_bus_unregister_driver(&acpi_battery_driver);
 881 #ifdef CONFIG_ACPI_PROCFS_POWER
 882         acpi_unlock_battery_dir(acpi_battery_dir);
 883 #endif
 884 }
 885
 886 module_init(acpi_battery_init);
 887 module_exit(acpi_battery_exit);