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 #include <linux/async.h>
  34 #include <linux/dmi.h>
  35 #include <linux/slab.h>
  36
  37 #ifdef CONFIG_ACPI_PROCFS_POWER
  38 #include <linux/proc_fs.h>
  39 #include <linux/seq_file.h>
  40 #include <asm/uaccess.h>
  41 #endif
  42
  43 #include <acpi/acpi_bus.h>
  44 #include <acpi/acpi_drivers.h>
  45
  46 #ifdef CONFIG_ACPI_SYSFS_POWER
  47 #include <linux/power_supply.h>
  48 #endif
  49
  50 #define PREFIX "ACPI: "
  51
  52 #define ACPI_BATTERY_VALUE_UNKNOWN 0xFFFFFFFF
  53
  54 #define ACPI_BATTERY_CLASS              "battery"
  55 #define ACPI_BATTERY_DEVICE_NAME        "Battery"
  56 #define ACPI_BATTERY_NOTIFY_STATUS      0x80
  57 #define ACPI_BATTERY_NOTIFY_INFO        0x81
  58 #define ACPI_BATTERY_NOTIFY_THRESHOLD   0x82
  59
  60 #define _COMPONENT              ACPI_BATTERY_COMPONENT
  61
  62 ACPI_MODULE_NAME("battery");
  63
  64 MODULE_AUTHOR("Paul Diefenbaugh");
  65 MODULE_AUTHOR("Alexey Starikovskiy <astarikovskiy@suse.de>");
  66 MODULE_DESCRIPTION("ACPI Battery Driver");
  67 MODULE_LICENSE("GPL");
  68
  69 static unsigned int cache_time = 1000;
  70 module_param(cache_time, uint, 0644);
  71 MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
  72
  73 #ifdef CONFIG_ACPI_PROCFS_POWER
  74 extern struct proc_dir_entry *acpi_lock_battery_dir(void);
  75 extern void *acpi_unlock_battery_dir(struct proc_dir_entry *acpi_battery_dir);
  76
  77 enum acpi_battery_files {
  78         info_tag = 0,
  79         state_tag,
  80         alarm_tag,
  81         ACPI_BATTERY_NUMFILES,
  82 };
  83
  84 #endif
  85
  86 static const struct acpi_device_id battery_device_ids[] = {
  87         {"PNP0C0A", 0},
  88         {"", 0},
  89 };
  90
  91 MODULE_DEVICE_TABLE(acpi, battery_device_ids);
  92
  93 enum {
  94         ACPI_BATTERY_ALARM_PRESENT,
  95         ACPI_BATTERY_XINFO_PRESENT,
  96         /* For buggy DSDTs that report negative 16-bit values for either
  97          * charging or discharging current and/or report 0 as 65536
  98          * due to bad math.
  99          */
 100         ACPI_BATTERY_QUIRK_SIGNED16_CURRENT,
 101 };
 102
 103 struct acpi_battery {
 104         struct mutex lock;
 105 #ifdef CONFIG_ACPI_SYSFS_POWER
 106         struct power_supply bat;
 107 #endif
 108         struct acpi_device *device;
 109         unsigned long update_time;
 110         int rate_now;
 111         int capacity_now;
 112         int voltage_now;
 113         int design_capacity;
 114         int full_charge_capacity;
 115         int technology;
 116         int design_voltage;
 117         int design_capacity_warning;
 118         int design_capacity_low;
 119         int cycle_count;
 120         int measurement_accuracy;
 121         int max_sampling_time;
 122         int min_sampling_time;
 123         int max_averaging_interval;
 124         int min_averaging_interval;
 125         int capacity_granularity_1;
 126         int capacity_granularity_2;
 127         int alarm;
 128         char model_number[32];
 129         char serial_number[32];
 130         char type[32];
 131         char oem_info[32];
 132         int state;
 133         int power_unit;
 134         unsigned long flags;
 135 };
 136
 137 #define to_acpi_battery(x) container_of(x, struct acpi_battery, bat);
 138
 139 inline int acpi_battery_present(struct acpi_battery *battery)
 140 {
 141         return battery->device->status.battery_present;
 142 }
 143
 144 #ifdef CONFIG_ACPI_SYSFS_POWER
 145 static int acpi_battery_technology(struct acpi_battery *battery)
 146 {
 147         if (!strcasecmp("NiCd", battery->type))
 148                 return POWER_SUPPLY_TECHNOLOGY_NiCd;
 149         if (!strcasecmp("NiMH", battery->type))
 150                 return POWER_SUPPLY_TECHNOLOGY_NiMH;
 151         if (!strcasecmp("LION", battery->type))
 152                 return POWER_SUPPLY_TECHNOLOGY_LION;
 153         if (!strncasecmp("LI-ION", battery->type, 6))
 154                 return POWER_SUPPLY_TECHNOLOGY_LION;
 155         if (!strcasecmp("LiP", battery->type))
 156                 return POWER_SUPPLY_TECHNOLOGY_LIPO;
 157         return POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
 158 }
 159
 160 static int acpi_battery_get_state(struct acpi_battery *battery);
 161
 162 static int acpi_battery_is_charged(struct acpi_battery *battery)
 163 {
 164         /* either charging or discharging */
 165         if (battery->state != 0)
 166                 return 0;
 167
 168         /* battery not reporting charge */
 169         if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN ||
 170             battery->capacity_now == 0)
 171                 return 0;
 172
 173         /* good batteries update full_charge as the batteries degrade */
 174         if (battery->full_charge_capacity == battery->capacity_now)
 175                 return 1;
 176
 177         /* fallback to using design values for broken batteries */
 178         if (battery->design_capacity == battery->capacity_now)
 179                 return 1;
 180
 181         /* we don't do any sort of metric based on percentages */
 182         return 0;
 183 }
 184
 185 static int acpi_battery_get_property(struct power_supply *psy,
 186                                      enum power_supply_property psp,
 187                                      union power_supply_propval *val)
 188 {
 189         struct acpi_battery *battery = to_acpi_battery(psy);
 190
 191         if (acpi_battery_present(battery)) {
 192                 /* run battery update only if it is present */
 193                 acpi_battery_get_state(battery);
 194         } else if (psp != POWER_SUPPLY_PROP_PRESENT)
 195                 return -ENODEV;
 196         switch (psp) {
 197         case POWER_SUPPLY_PROP_STATUS:
 198                 if (battery->state & 0x01)
 199                         val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
 200                 else if (battery->state & 0x02)
 201                         val->intval = POWER_SUPPLY_STATUS_CHARGING;
 202                 else if (acpi_battery_is_charged(battery))
 203                         val->intval = POWER_SUPPLY_STATUS_FULL;
 204                 else
 205                         val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
 206                 break;
 207         case POWER_SUPPLY_PROP_PRESENT:
 208                 val->intval = acpi_battery_present(battery);
 209                 break;
 210         case POWER_SUPPLY_PROP_TECHNOLOGY:
 211                 val->intval = acpi_battery_technology(battery);
 212                 break;
 213         case POWER_SUPPLY_PROP_CYCLE_COUNT:
 214                 val->intval = battery->cycle_count;
 215                 break;
 216         case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
 217                 val->intval = battery->design_voltage * 1000;
 218                 break;
 219         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 220                 val->intval = battery->voltage_now * 1000;
 221                 break;
 222         case POWER_SUPPLY_PROP_CURRENT_NOW:
 223         case POWER_SUPPLY_PROP_POWER_NOW:
 224                 val->intval = battery->rate_now * 1000;
 225                 break;
 226         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
 227         case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
 228                 val->intval = battery->design_capacity * 1000;
 229                 break;
 230         case POWER_SUPPLY_PROP_CHARGE_FULL:
 231         case POWER_SUPPLY_PROP_ENERGY_FULL:
 232                 val->intval = battery->full_charge_capacity * 1000;
 233                 break;
 234         case POWER_SUPPLY_PROP_CHARGE_NOW:
 235         case POWER_SUPPLY_PROP_ENERGY_NOW:
 236                 val->intval = battery->capacity_now * 1000;
 237                 break;
 238         case POWER_SUPPLY_PROP_MODEL_NAME:
 239                 val->strval = battery->model_number;
 240                 break;
 241         case POWER_SUPPLY_PROP_MANUFACTURER:
 242                 val->strval = battery->oem_info;
 243                 break;
 244         case POWER_SUPPLY_PROP_SERIAL_NUMBER:
 245                 val->strval = battery->serial_number;
 246                 break;
 247         default:
 248                 return -EINVAL;
 249         }
 250         return 0;
 251 }
 252
 253 static enum power_supply_property charge_battery_props[] = {
 254         POWER_SUPPLY_PROP_STATUS,
 255         POWER_SUPPLY_PROP_PRESENT,
 256         POWER_SUPPLY_PROP_TECHNOLOGY,
 257         POWER_SUPPLY_PROP_CYCLE_COUNT,
 258         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 259         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 260         POWER_SUPPLY_PROP_CURRENT_NOW,
 261         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 262         POWER_SUPPLY_PROP_CHARGE_FULL,
 263         POWER_SUPPLY_PROP_CHARGE_NOW,
 264         POWER_SUPPLY_PROP_MODEL_NAME,
 265         POWER_SUPPLY_PROP_MANUFACTURER,
 266         POWER_SUPPLY_PROP_SERIAL_NUMBER,
 267 };
 268
 269 static enum power_supply_property energy_battery_props[] = {
 270         POWER_SUPPLY_PROP_STATUS,
 271         POWER_SUPPLY_PROP_PRESENT,
 272         POWER_SUPPLY_PROP_TECHNOLOGY,
 273         POWER_SUPPLY_PROP_CYCLE_COUNT,
 274         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 275         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 276         POWER_SUPPLY_PROP_POWER_NOW,
 277         POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
 278         POWER_SUPPLY_PROP_ENERGY_FULL,
 279         POWER_SUPPLY_PROP_ENERGY_NOW,
 280         POWER_SUPPLY_PROP_MODEL_NAME,
 281         POWER_SUPPLY_PROP_MANUFACTURER,
 282         POWER_SUPPLY_PROP_SERIAL_NUMBER,
 283 };
 284 #endif
 285
 286 #ifdef CONFIG_ACPI_PROCFS_POWER
 287 inline char *acpi_battery_units(struct acpi_battery *battery)
 288 {
 289         return (battery->power_unit)?"mA":"mW";
 290 }
 291 #endif
 292
 293 /* --------------------------------------------------------------------------
 294                                Battery Management
 295    -------------------------------------------------------------------------- */
 296 struct acpi_offsets {
 297         size_t offset;          /* offset inside struct acpi_sbs_battery */
 298         u8 mode;                /* int or string? */
 299 };
 300
 301 static struct acpi_offsets state_offsets[] = {
 302         {offsetof(struct acpi_battery, state), 0},
 303         {offsetof(struct acpi_battery, rate_now), 0},
 304         {offsetof(struct acpi_battery, capacity_now), 0},
 305         {offsetof(struct acpi_battery, voltage_now), 0},
 306 };
 307
 308 static struct acpi_offsets info_offsets[] = {
 309         {offsetof(struct acpi_battery, power_unit), 0},
 310         {offsetof(struct acpi_battery, design_capacity), 0},
 311         {offsetof(struct acpi_battery, full_charge_capacity), 0},
 312         {offsetof(struct acpi_battery, technology), 0},
 313         {offsetof(struct acpi_battery, design_voltage), 0},
 314         {offsetof(struct acpi_battery, design_capacity_warning), 0},
 315         {offsetof(struct acpi_battery, design_capacity_low), 0},
 316         {offsetof(struct acpi_battery, capacity_granularity_1), 0},
 317         {offsetof(struct acpi_battery, capacity_granularity_2), 0},
 318         {offsetof(struct acpi_battery, model_number), 1},
 319         {offsetof(struct acpi_battery, serial_number), 1},
 320         {offsetof(struct acpi_battery, type), 1},
 321         {offsetof(struct acpi_battery, oem_info), 1},
 322 };
 323
 324 static struct acpi_offsets extended_info_offsets[] = {
 325         {offsetof(struct acpi_battery, power_unit), 0},
 326         {offsetof(struct acpi_battery, design_capacity), 0},
 327         {offsetof(struct acpi_battery, full_charge_capacity), 0},
 328         {offsetof(struct acpi_battery, technology), 0},
 329         {offsetof(struct acpi_battery, design_voltage), 0},
 330         {offsetof(struct acpi_battery, design_capacity_warning), 0},
 331         {offsetof(struct acpi_battery, design_capacity_low), 0},
 332         {offsetof(struct acpi_battery, cycle_count), 0},
 333         {offsetof(struct acpi_battery, measurement_accuracy), 0},
 334         {offsetof(struct acpi_battery, max_sampling_time), 0},
 335         {offsetof(struct acpi_battery, min_sampling_time), 0},
 336         {offsetof(struct acpi_battery, max_averaging_interval), 0},
 337         {offsetof(struct acpi_battery, min_averaging_interval), 0},
 338         {offsetof(struct acpi_battery, capacity_granularity_1), 0},
 339         {offsetof(struct acpi_battery, capacity_granularity_2), 0},
 340         {offsetof(struct acpi_battery, model_number), 1},
 341         {offsetof(struct acpi_battery, serial_number), 1},
 342         {offsetof(struct acpi_battery, type), 1},
 343         {offsetof(struct acpi_battery, oem_info), 1},
 344 };
 345
 346 static int extract_package(struct acpi_battery *battery,
 347                            union acpi_object *package,
 348                            struct acpi_offsets *offsets, int num)
 349 {
 350         int i;
 351         union acpi_object *element;
 352         if (package->type != ACPI_TYPE_PACKAGE)
 353                 return -EFAULT;
 354         for (i = 0; i < num; ++i) {
 355                 if (package->package.count <= i)
 356                         return -EFAULT;
 357                 element = &package->package.elements[i];
 358                 if (offsets[i].mode) {
 359                         u8 *ptr = (u8 *)battery + offsets[i].offset;
 360                         if (element->type == ACPI_TYPE_STRING ||
 361                             element->type == ACPI_TYPE_BUFFER)
 362                                 strncpy(ptr, element->string.pointer, 32);
 363                         else if (element->type == ACPI_TYPE_INTEGER) {
 364                                 strncpy(ptr, (u8 *)&element->integer.value,
 365                                         sizeof(u64));
 366                                 ptr[sizeof(u64)] = 0;
 367                         } else
 368                                 *ptr = 0; /* don't have value */
 369                 } else {
 370                         int *x = (int *)((u8 *)battery + offsets[i].offset);
 371                         *x = (element->type == ACPI_TYPE_INTEGER) ?
 372                                 element->integer.value : -1;
 373                 }
 374         }
 375         return 0;
 376 }
 377
 378 static int acpi_battery_get_status(struct acpi_battery *battery)
 379 {
 380         if (acpi_bus_get_status(battery->device)) {
 381                 ACPI_EXCEPTION((AE_INFO, AE_ERROR, "Evaluating _STA"));
 382                 return -ENODEV;
 383         }
 384         return 0;
 385 }
 386
 387 static int acpi_battery_get_info(struct acpi_battery *battery)
 388 {
 389         int result = -EFAULT;
 390         acpi_status status = 0;
 391         char *name = test_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags)?
 392                         "_BIX" : "_BIF";
 393
 394         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 395
 396         if (!acpi_battery_present(battery))
 397                 return 0;
 398         mutex_lock(&battery->lock);
 399         status = acpi_evaluate_object(battery->device->handle, name,
 400                                                 NULL, &buffer);
 401         mutex_unlock(&battery->lock);
 402
 403         if (ACPI_FAILURE(status)) {
 404                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating %s", name));
 405                 return -ENODEV;
 406         }
 407         if (test_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags))
 408                 result = extract_package(battery, buffer.pointer,
 409                                 extended_info_offsets,
 410                                 ARRAY_SIZE(extended_info_offsets));
 411         else
 412                 result = extract_package(battery, buffer.pointer,
 413                                 info_offsets, ARRAY_SIZE(info_offsets));
 414         kfree(buffer.pointer);
 415         return result;
 416 }
 417
 418 static int acpi_battery_get_state(struct acpi_battery *battery)
 419 {
 420         int result = 0;
 421         acpi_status status = 0;
 422         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 423
 424         if (!acpi_battery_present(battery))
 425                 return 0;
 426
 427         if (battery->update_time &&
 428             time_before(jiffies, battery->update_time +
 429                         msecs_to_jiffies(cache_time)))
 430                 return 0;
 431
 432         mutex_lock(&battery->lock);
 433         status = acpi_evaluate_object(battery->device->handle, "_BST",
 434                                       NULL, &buffer);
 435         mutex_unlock(&battery->lock);
 436
 437         if (ACPI_FAILURE(status)) {
 438                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BST"));
 439                 return -ENODEV;
 440         }
 441
 442         result = extract_package(battery, buffer.pointer,
 443                                  state_offsets, ARRAY_SIZE(state_offsets));
 444         battery->update_time = jiffies;
 445         kfree(buffer.pointer);
 446
 447         if (test_bit(ACPI_BATTERY_QUIRK_SIGNED16_CURRENT, &battery->flags) &&
 448             battery->rate_now != -1)
 449                 battery->rate_now = abs((s16)battery->rate_now);
 450
 451         return result;
 452 }
 453
 454 static int acpi_battery_set_alarm(struct acpi_battery *battery)
 455 {
 456         acpi_status status = 0;
 457         union acpi_object arg0 = { .type = ACPI_TYPE_INTEGER };
 458         struct acpi_object_list arg_list = { 1, &arg0 };
 459
 460         if (!acpi_battery_present(battery) ||
 461             !test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags))
 462                 return -ENODEV;
 463
 464         arg0.integer.value = battery->alarm;
 465
 466         mutex_lock(&battery->lock);
 467         status = acpi_evaluate_object(battery->device->handle, "_BTP",
 468                                  &arg_list, NULL);
 469         mutex_unlock(&battery->lock);
 470
 471         if (ACPI_FAILURE(status))
 472                 return -ENODEV;
 473
 474         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Alarm set to %d\n", battery->alarm));
 475         return 0;
 476 }
 477
 478 static int acpi_battery_init_alarm(struct acpi_battery *battery)
 479 {
 480         acpi_status status = AE_OK;
 481         acpi_handle handle = NULL;
 482
 483         /* See if alarms are supported, and if so, set default */
 484         status = acpi_get_handle(battery->device->handle, "_BTP", &handle);
 485         if (ACPI_FAILURE(status)) {
 486                 clear_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags);
 487                 return 0;
 488         }
 489         set_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags);
 490         if (!battery->alarm)
 491                 battery->alarm = battery->design_capacity_warning;
 492         return acpi_battery_set_alarm(battery);
 493 }
 494
 495 #ifdef CONFIG_ACPI_SYSFS_POWER
 496 static ssize_t acpi_battery_alarm_show(struct device *dev,
 497                                         struct device_attribute *attr,
 498                                         char *buf)
 499 {
 500         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
 501         return sprintf(buf, "%d\n", battery->alarm * 1000);
 502 }
 503
 504 static ssize_t acpi_battery_alarm_store(struct device *dev,
 505                                         struct device_attribute *attr,
 506                                         const char *buf, size_t count)
 507 {
 508         unsigned long x;
 509         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
 510         if (sscanf(buf, "%ld\n", &x) == 1)
 511                 battery->alarm = x/1000;
 512         if (acpi_battery_present(battery))
 513                 acpi_battery_set_alarm(battery);
 514         return count;
 515 }
 516
 517 static struct device_attribute alarm_attr = {
 518         .attr = {.name = "alarm", .mode = 0644},
 519         .show = acpi_battery_alarm_show,
 520         .store = acpi_battery_alarm_store,
 521 };
 522
 523 static int sysfs_add_battery(struct acpi_battery *battery)
 524 {
 525         int result;
 526
 527         if (battery->power_unit) {
 528                 battery->bat.properties = charge_battery_props;
 529                 battery->bat.num_properties =
 530                         ARRAY_SIZE(charge_battery_props);
 531         } else {
 532                 battery->bat.properties = energy_battery_props;
 533                 battery->bat.num_properties =
 534                         ARRAY_SIZE(energy_battery_props);
 535         }
 536
 537         battery->bat.name = acpi_device_bid(battery->device);
 538         battery->bat.type = POWER_SUPPLY_TYPE_BATTERY;
 539         battery->bat.get_property = acpi_battery_get_property;
 540
 541         result = power_supply_register(&battery->device->dev, &battery->bat);
 542         if (result)
 543                 return result;
 544         return device_create_file(battery->bat.dev, &alarm_attr);
 545 }
 546
 547 static void sysfs_remove_battery(struct acpi_battery *battery)
 548 {
 549         if (!battery->bat.dev)
 550                 return;
 551         device_remove_file(battery->bat.dev, &alarm_attr);
 552         power_supply_unregister(&battery->bat);
 553         battery->bat.dev = NULL;
 554 }
 555 #endif
 556
 557 static void acpi_battery_quirks(struct acpi_battery *battery)
 558 {
 559         if (dmi_name_in_vendors("Acer") && battery->power_unit) {
 560                 set_bit(ACPI_BATTERY_QUIRK_SIGNED16_CURRENT, &battery->flags);
 561         }
 562 }
 563
 564 static int acpi_battery_update(struct acpi_battery *battery)
 565 {
 566         int result, old_present = acpi_battery_present(battery);
 567         result = acpi_battery_get_status(battery);
 568         if (result)
 569                 return result;
 570         if (!acpi_battery_present(battery)) {
 571 #ifdef CONFIG_ACPI_SYSFS_POWER
 572                 sysfs_remove_battery(battery);
 573 #endif
 574                 battery->update_time = 0;
 575                 return 0;
 576         }
 577         if (!battery->update_time ||
 578             old_present != acpi_battery_present(battery)) {
 579                 result = acpi_battery_get_info(battery);
 580                 if (result)
 581                         return result;
 582                 acpi_battery_quirks(battery);
 583                 acpi_battery_init_alarm(battery);
 584         }
 585 #ifdef CONFIG_ACPI_SYSFS_POWER
 586         if (!battery->bat.dev)
 587                 sysfs_add_battery(battery);
 588 #endif
 589         return acpi_battery_get_state(battery);
 590 }
 591
 592 /* --------------------------------------------------------------------------
 593                               FS Interface (/proc)
 594    -------------------------------------------------------------------------- */
 595
 596 #ifdef CONFIG_ACPI_PROCFS_POWER
 597 static struct proc_dir_entry *acpi_battery_dir;
 598
 599 static int acpi_battery_print_info(struct seq_file *seq, int result)
 600 {
 601         struct acpi_battery *battery = seq->private;
 602
 603         if (result)
 604                 goto end;
 605
 606         seq_printf(seq, "present:                 %s\n",
 607                    acpi_battery_present(battery)?"yes":"no");
 608         if (!acpi_battery_present(battery))
 609                 goto end;
 610         if (battery->design_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
 611                 seq_printf(seq, "design capacity:         unknown\n");
 612         else
 613                 seq_printf(seq, "design capacity:         %d %sh\n",
 614                            battery->design_capacity,
 615                            acpi_battery_units(battery));
 616
 617         if (battery->full_charge_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
 618                 seq_printf(seq, "last full capacity:      unknown\n");
 619         else
 620                 seq_printf(seq, "last full capacity:      %d %sh\n",
 621                            battery->full_charge_capacity,
 622                            acpi_battery_units(battery));
 623
 624         seq_printf(seq, "battery technology:      %srechargeable\n",
 625                    (!battery->technology)?"non-":"");
 626
 627         if (battery->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
 628                 seq_printf(seq, "design voltage:          unknown\n");
 629         else
 630                 seq_printf(seq, "design voltage:          %d mV\n",
 631                            battery->design_voltage);
 632         seq_printf(seq, "design capacity warning: %d %sh\n",
 633                    battery->design_capacity_warning,
 634                    acpi_battery_units(battery));
 635         seq_printf(seq, "design capacity low:     %d %sh\n",
 636                    battery->design_capacity_low,
 637                    acpi_battery_units(battery));
 638         seq_printf(seq, "cycle count:             %i\n", battery->cycle_count);
 639         seq_printf(seq, "capacity granularity 1:  %d %sh\n",
 640                    battery->capacity_granularity_1,
 641                    acpi_battery_units(battery));
 642         seq_printf(seq, "capacity granularity 2:  %d %sh\n",
 643                    battery->capacity_granularity_2,
 644                    acpi_battery_units(battery));
 645         seq_printf(seq, "model number:            %s\n", battery->model_number);
 646         seq_printf(seq, "serial number:           %s\n", battery->serial_number);
 647         seq_printf(seq, "battery type:            %s\n", battery->type);
 648         seq_printf(seq, "OEM info:                %s\n", battery->oem_info);
 649       end:
 650         if (result)
 651                 seq_printf(seq, "ERROR: Unable to read battery info\n");
 652         return result;
 653 }
 654
 655 static int acpi_battery_print_state(struct seq_file *seq, int result)
 656 {
 657         struct acpi_battery *battery = seq->private;
 658
 659         if (result)
 660                 goto end;
 661
 662         seq_printf(seq, "present:                 %s\n",
 663                    acpi_battery_present(battery)?"yes":"no");
 664         if (!acpi_battery_present(battery))
 665                 goto end;
 666
 667         seq_printf(seq, "capacity state:          %s\n",
 668                         (battery->state & 0x04)?"critical":"ok");
 669         if ((battery->state & 0x01) && (battery->state & 0x02))
 670                 seq_printf(seq,
 671                            "charging state:          charging/discharging\n");
 672         else if (battery->state & 0x01)
 673                 seq_printf(seq, "charging state:          discharging\n");
 674         else if (battery->state & 0x02)
 675                 seq_printf(seq, "charging state:          charging\n");
 676         else
 677                 seq_printf(seq, "charging state:          charged\n");
 678
 679         if (battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN)
 680                 seq_printf(seq, "present rate:            unknown\n");
 681         else
 682                 seq_printf(seq, "present rate:            %d %s\n",
 683                            battery->rate_now, acpi_battery_units(battery));
 684
 685         if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN)
 686                 seq_printf(seq, "remaining capacity:      unknown\n");
 687         else
 688                 seq_printf(seq, "remaining capacity:      %d %sh\n",
 689                            battery->capacity_now, acpi_battery_units(battery));
 690         if (battery->voltage_now == ACPI_BATTERY_VALUE_UNKNOWN)
 691                 seq_printf(seq, "present voltage:         unknown\n");
 692         else
 693                 seq_printf(seq, "present voltage:         %d mV\n",
 694                            battery->voltage_now);
 695       end:
 696         if (result)
 697                 seq_printf(seq, "ERROR: Unable to read battery state\n");
 698
 699         return result;
 700 }
 701
 702 static int acpi_battery_print_alarm(struct seq_file *seq, int result)
 703 {
 704         struct acpi_battery *battery = seq->private;
 705
 706         if (result)
 707                 goto end;
 708
 709         if (!acpi_battery_present(battery)) {
 710                 seq_printf(seq, "present:                 no\n");
 711                 goto end;
 712         }
 713         seq_printf(seq, "alarm:                   ");
 714         if (!battery->alarm)
 715                 seq_printf(seq, "unsupported\n");
 716         else
 717                 seq_printf(seq, "%u %sh\n", battery->alarm,
 718                                 acpi_battery_units(battery));
 719       end:
 720         if (result)
 721                 seq_printf(seq, "ERROR: Unable to read battery alarm\n");
 722         return result;
 723 }
 724
 725 static ssize_t acpi_battery_write_alarm(struct file *file,
 726                                         const char __user * buffer,
 727                                         size_t count, loff_t * ppos)
 728 {
 729         int result = 0;
 730         char alarm_string[12] = { '\0' };
 731         struct seq_file *m = file->private_data;
 732         struct acpi_battery *battery = m->private;
 733
 734         if (!battery || (count > sizeof(alarm_string) - 1))
 735                 return -EINVAL;
 736         if (!acpi_battery_present(battery)) {
 737                 result = -ENODEV;
 738                 goto end;
 739         }
 740         if (copy_from_user(alarm_string, buffer, count)) {
 741                 result = -EFAULT;
 742                 goto end;
 743         }
 744         alarm_string[count] = '\0';
 745         battery->alarm = simple_strtol(alarm_string, NULL, 0);
 746         result = acpi_battery_set_alarm(battery);
 747       end:
 748         if (!result)
 749                 return count;
 750         return result;
 751 }
 752
 753 typedef int(*print_func)(struct seq_file *seq, int result);
 754
 755 static print_func acpi_print_funcs[ACPI_BATTERY_NUMFILES] = {
 756         acpi_battery_print_info,
 757         acpi_battery_print_state,
 758         acpi_battery_print_alarm,
 759 };
 760
 761 static int acpi_battery_read(int fid, struct seq_file *seq)
 762 {
 763         struct acpi_battery *battery = seq->private;
 764         int result = acpi_battery_update(battery);
 765         return acpi_print_funcs[fid](seq, result);
 766 }
 767
 768 #define DECLARE_FILE_FUNCTIONS(_name) \
 769 static int acpi_battery_read_##_name(struct seq_file *seq, void *offset) \
 770 { \
 771         return acpi_battery_read(_name##_tag, seq); \
 772 } \
 773 static int acpi_battery_##_name##_open_fs(struct inode *inode, struct file *file) \
 774 { \
 775         return single_open(file, acpi_battery_read_##_name, PDE(inode)->data); \
 776 }
 777
 778 DECLARE_FILE_FUNCTIONS(info);
 779 DECLARE_FILE_FUNCTIONS(state);
 780 DECLARE_FILE_FUNCTIONS(alarm);
 781
 782 #undef DECLARE_FILE_FUNCTIONS
 783
 784 #define FILE_DESCRIPTION_RO(_name) \
 785         { \
 786         .name = __stringify(_name), \
 787         .mode = S_IRUGO, \
 788         .ops = { \
 789                 .open = acpi_battery_##_name##_open_fs, \
 790                 .read = seq_read, \
 791                 .llseek = seq_lseek, \
 792                 .release = single_release, \
 793                 .owner = THIS_MODULE, \
 794                 }, \
 795         }
 796
 797 #define FILE_DESCRIPTION_RW(_name) \
 798         { \
 799         .name = __stringify(_name), \
 800         .mode = S_IFREG | S_IRUGO | S_IWUSR, \
 801         .ops = { \
 802                 .open = acpi_battery_##_name##_open_fs, \
 803                 .read = seq_read, \
 804                 .llseek = seq_lseek, \
 805                 .write = acpi_battery_write_##_name, \
 806                 .release = single_release, \
 807                 .owner = THIS_MODULE, \
 808                 }, \
 809         }
 810
 811 static struct battery_file {
 812         struct file_operations ops;
 813         mode_t mode;
 814         const char *name;
 815 } acpi_battery_file[] = {
 816         FILE_DESCRIPTION_RO(info),
 817         FILE_DESCRIPTION_RO(state),
 818         FILE_DESCRIPTION_RW(alarm),
 819 };
 820
 821 #undef FILE_DESCRIPTION_RO
 822 #undef FILE_DESCRIPTION_RW
 823
 824 static int acpi_battery_add_fs(struct acpi_device *device)
 825 {
 826         struct proc_dir_entry *entry = NULL;
 827         int i;
 828
 829         if (!acpi_device_dir(device)) {
 830                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 831                                                      acpi_battery_dir);
 832                 if (!acpi_device_dir(device))
 833                         return -ENODEV;
 834         }
 835
 836         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i) {
 837                 entry = proc_create_data(acpi_battery_file[i].name,
 838                                          acpi_battery_file[i].mode,
 839                                          acpi_device_dir(device),
 840                                          &acpi_battery_file[i].ops,
 841                                          acpi_driver_data(device));
 842                 if (!entry)
 843                         return -ENODEV;
 844         }
 845         return 0;
 846 }
 847
 848 static void acpi_battery_remove_fs(struct acpi_device *device)
 849 {
 850         int i;
 851         if (!acpi_device_dir(device))
 852                 return;
 853         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i)
 854                 remove_proc_entry(acpi_battery_file[i].name,
 855                                   acpi_device_dir(device));
 856
 857         remove_proc_entry(acpi_device_bid(device), acpi_battery_dir);
 858         acpi_device_dir(device) = NULL;
 859 }
 860
 861 #endif
 862
 863 /* --------------------------------------------------------------------------
 864                                  Driver Interface
 865    -------------------------------------------------------------------------- */
 866
 867 static void acpi_battery_notify(struct acpi_device *device, u32 event)
 868 {
 869         struct acpi_battery *battery = acpi_driver_data(device);
 870 #ifdef CONFIG_ACPI_SYSFS_POWER
 871         struct device *old;
 872 #endif
 873
 874         if (!battery)
 875                 return;
 876 #ifdef CONFIG_ACPI_SYSFS_POWER
 877         old = battery->bat.dev;
 878 #endif
 879         acpi_battery_update(battery);
 880         acpi_bus_generate_proc_event(device, event,
 881                                      acpi_battery_present(battery));
 882         acpi_bus_generate_netlink_event(device->pnp.device_class,
 883                                         dev_name(&device->dev), event,
 884                                         acpi_battery_present(battery));
 885 #ifdef CONFIG_ACPI_SYSFS_POWER
 886         /* acpi_battery_update could remove power_supply object */
 887         if (old && battery->bat.dev)
 888                 power_supply_changed(&battery->bat);
 889 #endif
 890 }
 891
 892 static int acpi_battery_add(struct acpi_device *device)
 893 {
 894         int result = 0;
 895         struct acpi_battery *battery = NULL;
 896         acpi_handle handle;
 897         if (!device)
 898                 return -EINVAL;
 899         battery = kzalloc(sizeof(struct acpi_battery), GFP_KERNEL);
 900         if (!battery)
 901                 return -ENOMEM;
 902         battery->device = device;
 903         strcpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
 904         strcpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
 905         device->driver_data = battery;
 906         mutex_init(&battery->lock);
 907         if (ACPI_SUCCESS(acpi_get_handle(battery->device->handle,
 908                         "_BIX", &handle)))
 909                 set_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags);
 910         acpi_battery_update(battery);
 911 #ifdef CONFIG_ACPI_PROCFS_POWER
 912         result = acpi_battery_add_fs(device);
 913 #endif
 914         if (!result) {
 915                 printk(KERN_INFO PREFIX "%s Slot [%s] (battery %s)\n",
 916                         ACPI_BATTERY_DEVICE_NAME, acpi_device_bid(device),
 917                         device->status.battery_present ? "present" : "absent");
 918         } else {
 919 #ifdef CONFIG_ACPI_PROCFS_POWER
 920                 acpi_battery_remove_fs(device);
 921 #endif
 922                 kfree(battery);
 923         }
 924         return result;
 925 }
 926
 927 static int acpi_battery_remove(struct acpi_device *device, int type)
 928 {
 929         struct acpi_battery *battery = NULL;
 930
 931         if (!device || !acpi_driver_data(device))
 932                 return -EINVAL;
 933         battery = acpi_driver_data(device);
 934 #ifdef CONFIG_ACPI_PROCFS_POWER
 935         acpi_battery_remove_fs(device);
 936 #endif
 937 #ifdef CONFIG_ACPI_SYSFS_POWER
 938         sysfs_remove_battery(battery);
 939 #endif
 940         mutex_destroy(&battery->lock);
 941         kfree(battery);
 942         return 0;
 943 }
 944
 945 /* this is needed to learn about changes made in suspended state */
 946 static int acpi_battery_resume(struct acpi_device *device)
 947 {
 948         struct acpi_battery *battery;
 949         if (!device)
 950                 return -EINVAL;
 951         battery = acpi_driver_data(device);
 952         battery->update_time = 0;
 953         acpi_battery_update(battery);
 954         return 0;
 955 }
 956
 957 static struct acpi_driver acpi_battery_driver = {
 958         .name = "battery",
 959         .class = ACPI_BATTERY_CLASS,
 960         .ids = battery_device_ids,
 961         .flags = ACPI_DRIVER_ALL_NOTIFY_EVENTS,
 962         .ops = {
 963                 .add = acpi_battery_add,
 964                 .resume = acpi_battery_resume,
 965                 .remove = acpi_battery_remove,
 966                 .notify = acpi_battery_notify,
 967                 },
 968 };
 969
 970 static void __init acpi_battery_init_async(void *unused, async_cookie_t cookie)
 971 {
 972         if (acpi_disabled)
 973                 return;
 974 #ifdef CONFIG_ACPI_PROCFS_POWER
 975         acpi_battery_dir = acpi_lock_battery_dir();
 976         if (!acpi_battery_dir)
 977                 return;
 978 #endif
 979         if (acpi_bus_register_driver(&acpi_battery_driver) < 0) {
 980 #ifdef CONFIG_ACPI_PROCFS_POWER
 981                 acpi_unlock_battery_dir(acpi_battery_dir);
 982 #endif
 983                 return;
 984         }
 985         return;
 986 }
 987
 988 static int __init acpi_battery_init(void)
 989 {
 990         async_schedule(acpi_battery_init_async, NULL);
 991         return 0;
 992 }
 993
 994 static void __exit acpi_battery_exit(void)
 995 {
 996         acpi_bus_unregister_driver(&acpi_battery_driver);
 997 #ifdef CONFIG_ACPI_PROCFS_POWER
 998         acpi_unlock_battery_dir(acpi_battery_dir);
 999 #endif
1000 }
1001
1002 module_init(acpi_battery_init);
1003 module_exit(acpi_battery_exit);