drivers/acpi/battery.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  battery.c - ACPI Battery Driver (Revision: 2.0)
   4  *
   5  *  Copyright (C) 2007 Alexey Starikovskiy <[email protected]>
   6  *  Copyright (C) 2004-2007 Vladimir Lebedev <[email protected]>
   7  *  Copyright (C) 2001, 2002 Andy Grover <[email protected]>
   8  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <[email protected]>
   9  */
  10
  11 #define pr_fmt(fmt) "ACPI: battery: " fmt
  12
  13 #include <linux/async.h>
  14 #include <linux/delay.h>
  15 #include <linux/dmi.h>
  16 #include <linux/jiffies.h>
  17 #include <linux/kernel.h>
  18 #include <linux/list.h>
  19 #include <linux/module.h>
  20 #include <linux/mutex.h>
  21 #include <linux/slab.h>
  22 #include <linux/suspend.h>
  23 #include <linux/types.h>
  24
  25 #include <asm/unaligned.h>
  26
  27 #include <linux/acpi.h>
  28 #include <linux/power_supply.h>
  29
  30 #include <acpi/battery.h>
  31
  32 #define ACPI_BATTERY_VALUE_UNKNOWN 0xFFFFFFFF
  33 #define ACPI_BATTERY_CAPACITY_VALID(capacity) \
  34         ((capacity) != 0 && (capacity) != ACPI_BATTERY_VALUE_UNKNOWN)
  35
  36 #define ACPI_BATTERY_DEVICE_NAME        "Battery"
  37
  38 /* Battery power unit: 0 means mW, 1 means mA */
  39 #define ACPI_BATTERY_POWER_UNIT_MA      1
  40
  41 #define ACPI_BATTERY_STATE_DISCHARGING  0x1
  42 #define ACPI_BATTERY_STATE_CHARGING     0x2
  43 #define ACPI_BATTERY_STATE_CRITICAL     0x4
  44
  45 MODULE_AUTHOR("Paul Diefenbaugh");
  46 MODULE_AUTHOR("Alexey Starikovskiy <[email protected]>");
  47 MODULE_DESCRIPTION("ACPI Battery Driver");
  48 MODULE_LICENSE("GPL");
  49
  50 static async_cookie_t async_cookie;
  51 static bool battery_driver_registered;
  52 static int battery_bix_broken_package;
  53 static int battery_notification_delay_ms;
  54 static int battery_ac_is_broken;
  55 static unsigned int cache_time = 1000;
  56 module_param(cache_time, uint, 0644);
  57 MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
  58
  59 static const struct acpi_device_id battery_device_ids[] = {
  60         {"PNP0C0A", 0},
  61
  62         /* Microsoft Surface Go 3 */
  63         {"MSHW0146", 0},
  64
  65         {"", 0},
  66 };
  67
  68 MODULE_DEVICE_TABLE(acpi, battery_device_ids);
  69
  70 enum {
  71         ACPI_BATTERY_ALARM_PRESENT,
  72         ACPI_BATTERY_XINFO_PRESENT,
  73         ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY,
  74         /* On Lenovo Thinkpad models from 2010 and 2011, the power unit
  75          * switches between mWh and mAh depending on whether the system
  76          * is running on battery or not.  When mAh is the unit, most
  77          * reported values are incorrect and need to be adjusted by
  78          * 10000/design_voltage.  Verified on x201, t410, t410s, and x220.
  79          * Pre-2010 and 2012 models appear to always report in mWh and
  80          * are thus unaffected (tested with t42, t61, t500, x200, x300,
  81          * and x230).  Also, in mid-2012 Lenovo issued a BIOS update for
  82          *  the 2011 models that fixes the issue (tested on x220 with a
  83          * post-1.29 BIOS), but as of Nov. 2012, no such update is
  84          * available for the 2010 models.
  85          */
  86         ACPI_BATTERY_QUIRK_THINKPAD_MAH,
  87         /* for batteries reporting current capacity with design capacity
  88          * on a full charge, but showing degradation in full charge cap.
  89          */
  90         ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE,
  91 };
  92
  93 struct acpi_battery {
  94         struct mutex lock;
  95         struct mutex sysfs_lock;
  96         struct power_supply *bat;
  97         struct power_supply_desc bat_desc;
  98         struct acpi_device *device;
  99         struct notifier_block pm_nb;
 100         struct list_head list;
 101         unsigned long update_time;
 102         int revision;
 103         int rate_now;
 104         int capacity_now;
 105         int voltage_now;
 106         int design_capacity;
 107         int full_charge_capacity;
 108         int technology;
 109         int design_voltage;
 110         int design_capacity_warning;
 111         int design_capacity_low;
 112         int cycle_count;
 113         int measurement_accuracy;
 114         int max_sampling_time;
 115         int min_sampling_time;
 116         int max_averaging_interval;
 117         int min_averaging_interval;
 118         int capacity_granularity_1;
 119         int capacity_granularity_2;
 120         int alarm;
 121         char model_number[32];
 122         char serial_number[32];
 123         char type[32];
 124         char oem_info[32];
 125         int state;
 126         int power_unit;
 127         unsigned long flags;
 128 };
 129
 130 #define to_acpi_battery(x) power_supply_get_drvdata(x)
 131
 132 static inline int acpi_battery_present(struct acpi_battery *battery)
 133 {
 134         return battery->device->status.battery_present;
 135 }
 136
 137 static int acpi_battery_technology(struct acpi_battery *battery)
 138 {
 139         if (!strcasecmp("NiCd", battery->type))
 140                 return POWER_SUPPLY_TECHNOLOGY_NiCd;
 141         if (!strcasecmp("NiMH", battery->type))
 142                 return POWER_SUPPLY_TECHNOLOGY_NiMH;
 143         if (!strcasecmp("LION", battery->type))
 144                 return POWER_SUPPLY_TECHNOLOGY_LION;
 145         if (!strncasecmp("LI-ION", battery->type, 6))
 146                 return POWER_SUPPLY_TECHNOLOGY_LION;
 147         if (!strcasecmp("LiP", battery->type))
 148                 return POWER_SUPPLY_TECHNOLOGY_LIPO;
 149         return POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
 150 }
 151
 152 static int acpi_battery_get_state(struct acpi_battery *battery);
 153
 154 static int acpi_battery_is_charged(struct acpi_battery *battery)
 155 {
 156         /* charging, discharging or critical low */
 157         if (battery->state != 0)
 158                 return 0;
 159
 160         /* battery not reporting charge */
 161         if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN ||
 162             battery->capacity_now == 0)
 163                 return 0;
 164
 165         /* good batteries update full_charge as the batteries degrade */
 166         if (battery->full_charge_capacity == battery->capacity_now)
 167                 return 1;
 168
 169         /* fallback to using design values for broken batteries */
 170         if (battery->design_capacity <= battery->capacity_now)
 171                 return 1;
 172
 173         /* we don't do any sort of metric based on percentages */
 174         return 0;
 175 }
 176
 177 static bool acpi_battery_is_degraded(struct acpi_battery *battery)
 178 {
 179         return ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity) &&
 180                 ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity) &&
 181                 battery->full_charge_capacity < battery->design_capacity;
 182 }
 183
 184 static int acpi_battery_handle_discharging(struct acpi_battery *battery)
 185 {
 186         /*
 187          * Some devices wrongly report discharging if the battery's charge level
 188          * was above the device's start charging threshold atm the AC adapter
 189          * was plugged in and the device thus did not start a new charge cycle.
 190          */
 191         if ((battery_ac_is_broken || power_supply_is_system_supplied()) &&
 192             battery->rate_now == 0)
 193                 return POWER_SUPPLY_STATUS_NOT_CHARGING;
 194
 195         return POWER_SUPPLY_STATUS_DISCHARGING;
 196 }
 197
 198 static int acpi_battery_get_property(struct power_supply *psy,
 199                                      enum power_supply_property psp,
 200                                      union power_supply_propval *val)
 201 {
 202         int full_capacity = ACPI_BATTERY_VALUE_UNKNOWN, ret = 0;
 203         struct acpi_battery *battery = to_acpi_battery(psy);
 204
 205         if (acpi_battery_present(battery)) {
 206                 /* run battery update only if it is present */
 207                 acpi_battery_get_state(battery);
 208         } else if (psp != POWER_SUPPLY_PROP_PRESENT)
 209                 return -ENODEV;
 210         switch (psp) {
 211         case POWER_SUPPLY_PROP_STATUS:
 212                 if (battery->state & ACPI_BATTERY_STATE_DISCHARGING)
 213                         val->intval = acpi_battery_handle_discharging(battery);
 214                 else if (battery->state & ACPI_BATTERY_STATE_CHARGING)
 215                         val->intval = POWER_SUPPLY_STATUS_CHARGING;
 216                 else if (acpi_battery_is_charged(battery))
 217                         val->intval = POWER_SUPPLY_STATUS_FULL;
 218                 else
 219                         val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
 220                 break;
 221         case POWER_SUPPLY_PROP_PRESENT:
 222                 val->intval = acpi_battery_present(battery);
 223                 break;
 224         case POWER_SUPPLY_PROP_TECHNOLOGY:
 225                 val->intval = acpi_battery_technology(battery);
 226                 break;
 227         case POWER_SUPPLY_PROP_CYCLE_COUNT:
 228                 val->intval = battery->cycle_count;
 229                 break;
 230         case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
 231                 if (battery->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
 232                         ret = -ENODEV;
 233                 else
 234                         val->intval = battery->design_voltage * 1000;
 235                 break;
 236         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 237                 if (battery->voltage_now == ACPI_BATTERY_VALUE_UNKNOWN)
 238                         ret = -ENODEV;
 239                 else
 240                         val->intval = battery->voltage_now * 1000;
 241                 break;
 242         case POWER_SUPPLY_PROP_CURRENT_NOW:
 243         case POWER_SUPPLY_PROP_POWER_NOW:
 244                 if (battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN)
 245                         ret = -ENODEV;
 246                 else
 247                         val->intval = battery->rate_now * 1000;
 248                 break;
 249         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
 250         case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
 251                 if (!ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity))
 252                         ret = -ENODEV;
 253                 else
 254                         val->intval = battery->design_capacity * 1000;
 255                 break;
 256         case POWER_SUPPLY_PROP_CHARGE_FULL:
 257         case POWER_SUPPLY_PROP_ENERGY_FULL:
 258                 if (!ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity))
 259                         ret = -ENODEV;
 260                 else
 261                         val->intval = battery->full_charge_capacity * 1000;
 262                 break;
 263         case POWER_SUPPLY_PROP_CHARGE_NOW:
 264         case POWER_SUPPLY_PROP_ENERGY_NOW:
 265                 if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN)
 266                         ret = -ENODEV;
 267                 else
 268                         val->intval = battery->capacity_now * 1000;
 269                 break;
 270         case POWER_SUPPLY_PROP_CAPACITY:
 271                 if (ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity))
 272                         full_capacity = battery->full_charge_capacity;
 273                 else if (ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity))
 274                         full_capacity = battery->design_capacity;
 275
 276                 if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN ||
 277                     full_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
 278                         ret = -ENODEV;
 279                 else
 280                         val->intval = battery->capacity_now * 100/
 281                                         full_capacity;
 282                 break;
 283         case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
 284                 if (battery->state & ACPI_BATTERY_STATE_CRITICAL)
 285                         val->intval = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
 286                 else if (test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags) &&
 287                         (battery->capacity_now <= battery->alarm))
 288                         val->intval = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
 289                 else if (acpi_battery_is_charged(battery))
 290                         val->intval = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
 291                 else
 292                         val->intval = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
 293                 break;
 294         case POWER_SUPPLY_PROP_MODEL_NAME:
 295                 val->strval = battery->model_number;
 296                 break;
 297         case POWER_SUPPLY_PROP_MANUFACTURER:
 298                 val->strval = battery->oem_info;
 299                 break;
 300         case POWER_SUPPLY_PROP_SERIAL_NUMBER:
 301                 val->strval = battery->serial_number;
 302                 break;
 303         default:
 304                 ret = -EINVAL;
 305         }
 306         return ret;
 307 }
 308
 309 static enum power_supply_property charge_battery_props[] = {
 310         POWER_SUPPLY_PROP_STATUS,
 311         POWER_SUPPLY_PROP_PRESENT,
 312         POWER_SUPPLY_PROP_TECHNOLOGY,
 313         POWER_SUPPLY_PROP_CYCLE_COUNT,
 314         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 315         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 316         POWER_SUPPLY_PROP_CURRENT_NOW,
 317         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 318         POWER_SUPPLY_PROP_CHARGE_FULL,
 319         POWER_SUPPLY_PROP_CHARGE_NOW,
 320         POWER_SUPPLY_PROP_CAPACITY,
 321         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
 322         POWER_SUPPLY_PROP_MODEL_NAME,
 323         POWER_SUPPLY_PROP_MANUFACTURER,
 324         POWER_SUPPLY_PROP_SERIAL_NUMBER,
 325 };
 326
 327 static enum power_supply_property charge_battery_full_cap_broken_props[] = {
 328         POWER_SUPPLY_PROP_STATUS,
 329         POWER_SUPPLY_PROP_PRESENT,
 330         POWER_SUPPLY_PROP_TECHNOLOGY,
 331         POWER_SUPPLY_PROP_CYCLE_COUNT,
 332         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 333         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 334         POWER_SUPPLY_PROP_CURRENT_NOW,
 335         POWER_SUPPLY_PROP_CHARGE_NOW,
 336         POWER_SUPPLY_PROP_MODEL_NAME,
 337         POWER_SUPPLY_PROP_MANUFACTURER,
 338         POWER_SUPPLY_PROP_SERIAL_NUMBER,
 339 };
 340
 341 static enum power_supply_property energy_battery_props[] = {
 342         POWER_SUPPLY_PROP_STATUS,
 343         POWER_SUPPLY_PROP_PRESENT,
 344         POWER_SUPPLY_PROP_TECHNOLOGY,
 345         POWER_SUPPLY_PROP_CYCLE_COUNT,
 346         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 347         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 348         POWER_SUPPLY_PROP_POWER_NOW,
 349         POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
 350         POWER_SUPPLY_PROP_ENERGY_FULL,
 351         POWER_SUPPLY_PROP_ENERGY_NOW,
 352         POWER_SUPPLY_PROP_CAPACITY,
 353         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
 354         POWER_SUPPLY_PROP_MODEL_NAME,
 355         POWER_SUPPLY_PROP_MANUFACTURER,
 356         POWER_SUPPLY_PROP_SERIAL_NUMBER,
 357 };
 358
 359 static enum power_supply_property energy_battery_full_cap_broken_props[] = {
 360         POWER_SUPPLY_PROP_STATUS,
 361         POWER_SUPPLY_PROP_PRESENT,
 362         POWER_SUPPLY_PROP_TECHNOLOGY,
 363         POWER_SUPPLY_PROP_CYCLE_COUNT,
 364         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 365         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 366         POWER_SUPPLY_PROP_POWER_NOW,
 367         POWER_SUPPLY_PROP_ENERGY_NOW,
 368         POWER_SUPPLY_PROP_MODEL_NAME,
 369         POWER_SUPPLY_PROP_MANUFACTURER,
 370         POWER_SUPPLY_PROP_SERIAL_NUMBER,
 371 };
 372
 373 /* Battery Management */
 374 struct acpi_offsets {
 375         size_t offset;          /* offset inside struct acpi_sbs_battery */
 376         u8 mode;                /* int or string? */
 377 };
 378
 379 static const struct acpi_offsets state_offsets[] = {
 380         {offsetof(struct acpi_battery, state), 0},
 381         {offsetof(struct acpi_battery, rate_now), 0},
 382         {offsetof(struct acpi_battery, capacity_now), 0},
 383         {offsetof(struct acpi_battery, voltage_now), 0},
 384 };
 385
 386 static const struct acpi_offsets info_offsets[] = {
 387         {offsetof(struct acpi_battery, power_unit), 0},
 388         {offsetof(struct acpi_battery, design_capacity), 0},
 389         {offsetof(struct acpi_battery, full_charge_capacity), 0},
 390         {offsetof(struct acpi_battery, technology), 0},
 391         {offsetof(struct acpi_battery, design_voltage), 0},
 392         {offsetof(struct acpi_battery, design_capacity_warning), 0},
 393         {offsetof(struct acpi_battery, design_capacity_low), 0},
 394         {offsetof(struct acpi_battery, capacity_granularity_1), 0},
 395         {offsetof(struct acpi_battery, capacity_granularity_2), 0},
 396         {offsetof(struct acpi_battery, model_number), 1},
 397         {offsetof(struct acpi_battery, serial_number), 1},
 398         {offsetof(struct acpi_battery, type), 1},
 399         {offsetof(struct acpi_battery, oem_info), 1},
 400 };
 401
 402 static const struct acpi_offsets extended_info_offsets[] = {
 403         {offsetof(struct acpi_battery, revision), 0},
 404         {offsetof(struct acpi_battery, power_unit), 0},
 405         {offsetof(struct acpi_battery, design_capacity), 0},
 406         {offsetof(struct acpi_battery, full_charge_capacity), 0},
 407         {offsetof(struct acpi_battery, technology), 0},
 408         {offsetof(struct acpi_battery, design_voltage), 0},
 409         {offsetof(struct acpi_battery, design_capacity_warning), 0},
 410         {offsetof(struct acpi_battery, design_capacity_low), 0},
 411         {offsetof(struct acpi_battery, cycle_count), 0},
 412         {offsetof(struct acpi_battery, measurement_accuracy), 0},
 413         {offsetof(struct acpi_battery, max_sampling_time), 0},
 414         {offsetof(struct acpi_battery, min_sampling_time), 0},
 415         {offsetof(struct acpi_battery, max_averaging_interval), 0},
 416         {offsetof(struct acpi_battery, min_averaging_interval), 0},
 417         {offsetof(struct acpi_battery, capacity_granularity_1), 0},
 418         {offsetof(struct acpi_battery, capacity_granularity_2), 0},
 419         {offsetof(struct acpi_battery, model_number), 1},
 420         {offsetof(struct acpi_battery, serial_number), 1},
 421         {offsetof(struct acpi_battery, type), 1},
 422         {offsetof(struct acpi_battery, oem_info), 1},
 423 };
 424
 425 static int extract_package(struct acpi_battery *battery,
 426                            union acpi_object *package,
 427                            const struct acpi_offsets *offsets, int num)
 428 {
 429         int i;
 430         union acpi_object *element;
 431
 432         if (package->type != ACPI_TYPE_PACKAGE)
 433                 return -EFAULT;
 434         for (i = 0; i < num; ++i) {
 435                 if (package->package.count <= i)
 436                         return -EFAULT;
 437                 element = &package->package.elements[i];
 438                 if (offsets[i].mode) {
 439                         u8 *ptr = (u8 *)battery + offsets[i].offset;
 440
 441                         if (element->type == ACPI_TYPE_STRING ||
 442                             element->type == ACPI_TYPE_BUFFER)
 443                                 strncpy(ptr, element->string.pointer, 32);
 444                         else if (element->type == ACPI_TYPE_INTEGER) {
 445                                 strncpy(ptr, (u8 *)&element->integer.value,
 446                                         sizeof(u64));
 447                                 ptr[sizeof(u64)] = 0;
 448                         } else
 449                                 *ptr = 0; /* don't have value */
 450                 } else {
 451                         int *x = (int *)((u8 *)battery + offsets[i].offset);
 452                         *x = (element->type == ACPI_TYPE_INTEGER) ?
 453                                 element->integer.value : -1;
 454                 }
 455         }
 456         return 0;
 457 }
 458
 459 static int acpi_battery_get_status(struct acpi_battery *battery)
 460 {
 461         if (acpi_bus_get_status(battery->device)) {
 462                 acpi_handle_info(battery->device->handle,
 463                                  "_STA evaluation failed\n");
 464                 return -ENODEV;
 465         }
 466         return 0;
 467 }
 468
 469
 470 static int extract_battery_info(const int use_bix,
 471                          struct acpi_battery *battery,
 472                          const struct acpi_buffer *buffer)
 473 {
 474         int result = -EFAULT;
 475
 476         if (use_bix && battery_bix_broken_package)
 477                 result = extract_package(battery, buffer->pointer,
 478                                 extended_info_offsets + 1,
 479                                 ARRAY_SIZE(extended_info_offsets) - 1);
 480         else if (use_bix)
 481                 result = extract_package(battery, buffer->pointer,
 482                                 extended_info_offsets,
 483                                 ARRAY_SIZE(extended_info_offsets));
 484         else
 485                 result = extract_package(battery, buffer->pointer,
 486                                 info_offsets, ARRAY_SIZE(info_offsets));
 487         if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags))
 488                 battery->full_charge_capacity = battery->design_capacity;
 489         if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH, &battery->flags) &&
 490             battery->power_unit && battery->design_voltage) {
 491                 battery->design_capacity = battery->design_capacity *
 492                     10000 / battery->design_voltage;
 493                 battery->full_charge_capacity = battery->full_charge_capacity *
 494                     10000 / battery->design_voltage;
 495                 battery->design_capacity_warning =
 496                     battery->design_capacity_warning *
 497                     10000 / battery->design_voltage;
 498                 /* Curiously, design_capacity_low, unlike the rest of them,
 499                  *  is correct.
 500                  */
 501                 /* capacity_granularity_* equal 1 on the systems tested, so
 502                  * it's impossible to tell if they would need an adjustment
 503                  * or not if their values were higher.
 504                  */
 505         }
 506         if (test_bit(ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE, &battery->flags) &&
 507             battery->capacity_now > battery->full_charge_capacity)
 508                 battery->capacity_now = battery->full_charge_capacity;
 509
 510         return result;
 511 }
 512
 513 static int acpi_battery_get_info(struct acpi_battery *battery)
 514 {
 515         const int xinfo = test_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags);
 516         int use_bix;
 517         int result = -ENODEV;
 518
 519         if (!acpi_battery_present(battery))
 520                 return 0;
 521
 522
 523         for (use_bix = xinfo ? 1 : 0; use_bix >= 0; use_bix--) {
 524                 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 525                 acpi_status status = AE_ERROR;
 526
 527                 mutex_lock(&battery->lock);
 528                 status = acpi_evaluate_object(battery->device->handle,
 529                                               use_bix ? "_BIX":"_BIF",
 530                                               NULL, &buffer);
 531                 mutex_unlock(&battery->lock);
 532
 533                 if (ACPI_FAILURE(status)) {
 534                         acpi_handle_info(battery->device->handle,
 535                                          "%s evaluation failed: %s\n",
 536                                          use_bix ? "_BIX":"_BIF",
 537                                          acpi_format_exception(status));
 538                 } else {
 539                         result = extract_battery_info(use_bix,
 540                                                       battery,
 541                                                       &buffer);
 542
 543                         kfree(buffer.pointer);
 544                         break;
 545                 }
 546         }
 547
 548         if (!result && !use_bix && xinfo)
 549                 pr_warn(FW_BUG "The _BIX method is broken, using _BIF.\n");
 550
 551         return result;
 552 }
 553
 554 static int acpi_battery_get_state(struct acpi_battery *battery)
 555 {
 556         int result = 0;
 557         acpi_status status = 0;
 558         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 559
 560         if (!acpi_battery_present(battery))
 561                 return 0;
 562
 563         if (battery->update_time &&
 564             time_before(jiffies, battery->update_time +
 565                         msecs_to_jiffies(cache_time)))
 566                 return 0;
 567
 568         mutex_lock(&battery->lock);
 569         status = acpi_evaluate_object(battery->device->handle, "_BST",
 570                                       NULL, &buffer);
 571         mutex_unlock(&battery->lock);
 572
 573         if (ACPI_FAILURE(status)) {
 574                 acpi_handle_info(battery->device->handle,
 575                                  "_BST evaluation failed: %s",
 576                                  acpi_format_exception(status));
 577                 return -ENODEV;
 578         }
 579
 580         result = extract_package(battery, buffer.pointer,
 581                                  state_offsets, ARRAY_SIZE(state_offsets));
 582         battery->update_time = jiffies;
 583         kfree(buffer.pointer);
 584
 585         /* For buggy DSDTs that report negative 16-bit values for either
 586          * charging or discharging current and/or report 0 as 65536
 587          * due to bad math.
 588          */
 589         if (battery->power_unit == ACPI_BATTERY_POWER_UNIT_MA &&
 590                 battery->rate_now != ACPI_BATTERY_VALUE_UNKNOWN &&
 591                 (s16)(battery->rate_now) < 0) {
 592                 battery->rate_now = abs((s16)battery->rate_now);
 593                 pr_warn_once(FW_BUG "(dis)charge rate invalid.\n");
 594         }
 595
 596         if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags)
 597             && battery->capacity_now >= 0 && battery->capacity_now <= 100)
 598                 battery->capacity_now = (battery->capacity_now *
 599                                 battery->full_charge_capacity) / 100;
 600         if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH, &battery->flags) &&
 601             battery->power_unit && battery->design_voltage) {
 602                 battery->capacity_now = battery->capacity_now *
 603                     10000 / battery->design_voltage;
 604         }
 605         if (test_bit(ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE, &battery->flags) &&
 606             battery->capacity_now > battery->full_charge_capacity)
 607                 battery->capacity_now = battery->full_charge_capacity;
 608
 609         return result;
 610 }
 611
 612 static int acpi_battery_set_alarm(struct acpi_battery *battery)
 613 {
 614         acpi_status status = 0;
 615
 616         if (!acpi_battery_present(battery) ||
 617             !test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags))
 618                 return -ENODEV;
 619
 620         mutex_lock(&battery->lock);
 621         status = acpi_execute_simple_method(battery->device->handle, "_BTP",
 622                                             battery->alarm);
 623         mutex_unlock(&battery->lock);
 624
 625         if (ACPI_FAILURE(status))
 626                 return -ENODEV;
 627
 628         acpi_handle_debug(battery->device->handle, "Alarm set to %d\n",
 629                           battery->alarm);
 630
 631         return 0;
 632 }
 633
 634 static int acpi_battery_init_alarm(struct acpi_battery *battery)
 635 {
 636         /* See if alarms are supported, and if so, set default */
 637         if (!acpi_has_method(battery->device->handle, "_BTP")) {
 638                 clear_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags);
 639                 return 0;
 640         }
 641         set_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags);
 642         if (!battery->alarm)
 643                 battery->alarm = battery->design_capacity_warning;
 644         return acpi_battery_set_alarm(battery);
 645 }
 646
 647 static ssize_t acpi_battery_alarm_show(struct device *dev,
 648                                         struct device_attribute *attr,
 649                                         char *buf)
 650 {
 651         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
 652
 653         return sprintf(buf, "%d\n", battery->alarm * 1000);
 654 }
 655
 656 static ssize_t acpi_battery_alarm_store(struct device *dev,
 657                                         struct device_attribute *attr,
 658                                         const char *buf, size_t count)
 659 {
 660         unsigned long x;
 661         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
 662
 663         if (sscanf(buf, "%lu\n", &x) == 1)
 664                 battery->alarm = x/1000;
 665         if (acpi_battery_present(battery))
 666                 acpi_battery_set_alarm(battery);
 667         return count;
 668 }
 669
 670 static const struct device_attribute alarm_attr = {
 671         .attr = {.name = "alarm", .mode = 0644},
 672         .show = acpi_battery_alarm_show,
 673         .store = acpi_battery_alarm_store,
 674 };
 675
 676 /*
 677  * The Battery Hooking API
 678  *
 679  * This API is used inside other drivers that need to expose
 680  * platform-specific behaviour within the generic driver in a
 681  * generic way.
 682  *
 683  */
 684
 685 static LIST_HEAD(acpi_battery_list);
 686 static LIST_HEAD(battery_hook_list);
 687 static DEFINE_MUTEX(hook_mutex);
 688
 689 static void __battery_hook_unregister(struct acpi_battery_hook *hook, int lock)
 690 {
 691         struct acpi_battery *battery;
 692         /*
 693          * In order to remove a hook, we first need to
 694          * de-register all the batteries that are registered.
 695          */
 696         if (lock)
 697                 mutex_lock(&hook_mutex);
 698         list_for_each_entry(battery, &acpi_battery_list, list) {
 699                 if (!hook->remove_battery(battery->bat, hook))
 700                         power_supply_changed(battery->bat);
 701         }
 702         list_del(&hook->list);
 703         if (lock)
 704                 mutex_unlock(&hook_mutex);
 705         pr_info("extension unregistered: %s\n", hook->name);
 706 }
 707
 708 void battery_hook_unregister(struct acpi_battery_hook *hook)
 709 {
 710         __battery_hook_unregister(hook, 1);
 711 }
 712 EXPORT_SYMBOL_GPL(battery_hook_unregister);
 713
 714 void battery_hook_register(struct acpi_battery_hook *hook)
 715 {
 716         struct acpi_battery *battery;
 717
 718         mutex_lock(&hook_mutex);
 719         INIT_LIST_HEAD(&hook->list);
 720         list_add(&hook->list, &battery_hook_list);
 721         /*
 722          * Now that the driver is registered, we need
 723          * to notify the hook that a battery is available
 724          * for each battery, so that the driver may add
 725          * its attributes.
 726          */
 727         list_for_each_entry(battery, &acpi_battery_list, list) {
 728                 if (hook->add_battery(battery->bat, hook)) {
 729                         /*
 730                          * If a add-battery returns non-zero,
 731                          * the registration of the extension has failed,
 732                          * and we will not add it to the list of loaded
 733                          * hooks.
 734                          */
 735                         pr_err("extension failed to load: %s", hook->name);
 736                         __battery_hook_unregister(hook, 0);
 737                         goto end;
 738                 }
 739
 740                 power_supply_changed(battery->bat);
 741         }
 742         pr_info("new extension: %s\n", hook->name);
 743 end:
 744         mutex_unlock(&hook_mutex);
 745 }
 746 EXPORT_SYMBOL_GPL(battery_hook_register);
 747
 748 /*
 749  * This function gets called right after the battery sysfs
 750  * attributes have been added, so that the drivers that
 751  * define custom sysfs attributes can add their own.
 752  */
 753 static void battery_hook_add_battery(struct acpi_battery *battery)
 754 {
 755         struct acpi_battery_hook *hook_node, *tmp;
 756
 757         mutex_lock(&hook_mutex);
 758         INIT_LIST_HEAD(&battery->list);
 759         list_add(&battery->list, &acpi_battery_list);
 760         /*
 761          * Since we added a new battery to the list, we need to
 762          * iterate over the hooks and call add_battery for each
 763          * hook that was registered. This usually happens
 764          * when a battery gets hotplugged or initialized
 765          * during the battery module initialization.
 766          */
 767         list_for_each_entry_safe(hook_node, tmp, &battery_hook_list, list) {
 768                 if (hook_node->add_battery(battery->bat, hook_node)) {
 769                         /*
 770                          * The notification of the extensions has failed, to
 771                          * prevent further errors we will unload the extension.
 772                          */
 773                         pr_err("error in extension, unloading: %s",
 774                                         hook_node->name);
 775                         __battery_hook_unregister(hook_node, 0);
 776                 }
 777         }
 778         mutex_unlock(&hook_mutex);
 779 }
 780
 781 static void battery_hook_remove_battery(struct acpi_battery *battery)
 782 {
 783         struct acpi_battery_hook *hook;
 784
 785         mutex_lock(&hook_mutex);
 786         /*
 787          * Before removing the hook, we need to remove all
 788          * custom attributes from the battery.
 789          */
 790         list_for_each_entry(hook, &battery_hook_list, list) {
 791                 hook->remove_battery(battery->bat, hook);
 792         }
 793         /* Then, just remove the battery from the list */
 794         list_del(&battery->list);
 795         mutex_unlock(&hook_mutex);
 796 }
 797
 798 static void __exit battery_hook_exit(void)
 799 {
 800         struct acpi_battery_hook *hook;
 801         struct acpi_battery_hook *ptr;
 802         /*
 803          * At this point, the acpi_bus_unregister_driver()
 804          * has called remove for all batteries. We just
 805          * need to remove the hooks.
 806          */
 807         list_for_each_entry_safe(hook, ptr, &battery_hook_list, list) {
 808                 __battery_hook_unregister(hook, 1);
 809         }
 810         mutex_destroy(&hook_mutex);
 811 }
 812
 813 static int sysfs_add_battery(struct acpi_battery *battery)
 814 {
 815         struct power_supply_config psy_cfg = { .drv_data = battery, };
 816         bool full_cap_broken = false;
 817
 818         if (!ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity) &&
 819             !ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity))
 820                 full_cap_broken = true;
 821
 822         if (battery->power_unit == ACPI_BATTERY_POWER_UNIT_MA) {
 823                 if (full_cap_broken) {
 824                         battery->bat_desc.properties =
 825                             charge_battery_full_cap_broken_props;
 826                         battery->bat_desc.num_properties =
 827                             ARRAY_SIZE(charge_battery_full_cap_broken_props);
 828                 } else {
 829                         battery->bat_desc.properties = charge_battery_props;
 830                         battery->bat_desc.num_properties =
 831                             ARRAY_SIZE(charge_battery_props);
 832                 }
 833         } else {
 834                 if (full_cap_broken) {
 835                         battery->bat_desc.properties =
 836                             energy_battery_full_cap_broken_props;
 837                         battery->bat_desc.num_properties =
 838                             ARRAY_SIZE(energy_battery_full_cap_broken_props);
 839                 } else {
 840                         battery->bat_desc.properties = energy_battery_props;
 841                         battery->bat_desc.num_properties =
 842                             ARRAY_SIZE(energy_battery_props);
 843                 }
 844         }
 845
 846         battery->bat_desc.name = acpi_device_bid(battery->device);
 847         battery->bat_desc.type = POWER_SUPPLY_TYPE_BATTERY;
 848         battery->bat_desc.get_property = acpi_battery_get_property;
 849
 850         battery->bat = power_supply_register_no_ws(&battery->device->dev,
 851                                 &battery->bat_desc, &psy_cfg);
 852
 853         if (IS_ERR(battery->bat)) {
 854                 int result = PTR_ERR(battery->bat);
 855
 856                 battery->bat = NULL;
 857                 return result;
 858         }
 859         battery_hook_add_battery(battery);
 860         return device_create_file(&battery->bat->dev, &alarm_attr);
 861 }
 862
 863 static void sysfs_remove_battery(struct acpi_battery *battery)
 864 {
 865         mutex_lock(&battery->sysfs_lock);
 866         if (!battery->bat) {
 867                 mutex_unlock(&battery->sysfs_lock);
 868                 return;
 869         }
 870         battery_hook_remove_battery(battery);
 871         device_remove_file(&battery->bat->dev, &alarm_attr);
 872         power_supply_unregister(battery->bat);
 873         battery->bat = NULL;
 874         mutex_unlock(&battery->sysfs_lock);
 875 }
 876
 877 static void find_battery(const struct dmi_header *dm, void *private)
 878 {
 879         struct acpi_battery *battery = (struct acpi_battery *)private;
 880         /* Note: the hardcoded offsets below have been extracted from
 881          * the source code of dmidecode.
 882          */
 883         if (dm->type == DMI_ENTRY_PORTABLE_BATTERY && dm->length >= 8) {
 884                 const u8 *dmi_data = (const u8 *)(dm + 1);
 885                 int dmi_capacity = get_unaligned((const u16 *)(dmi_data + 6));
 886
 887                 if (dm->length >= 18)
 888                         dmi_capacity *= dmi_data[17];
 889                 if (battery->design_capacity * battery->design_voltage / 1000
 890                     != dmi_capacity &&
 891                     battery->design_capacity * 10 == dmi_capacity)
 892                         set_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH,
 893                                 &battery->flags);
 894         }
 895 }
 896
 897 /*
 898  * According to the ACPI spec, some kinds of primary batteries can
 899  * report percentage battery remaining capacity directly to OS.
 900  * In this case, it reports the Last Full Charged Capacity == 100
 901  * and BatteryPresentRate == 0xFFFFFFFF.
 902  *
 903  * Now we found some battery reports percentage remaining capacity
 904  * even if it's rechargeable.
 905  * https://bugzilla.kernel.org/show_bug.cgi?id=15979
 906  *
 907  * Handle this correctly so that they won't break userspace.
 908  */
 909 static void acpi_battery_quirks(struct acpi_battery *battery)
 910 {
 911         if (test_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags))
 912                 return;
 913
 914         if (battery->full_charge_capacity == 100 &&
 915                 battery->rate_now == ACPI_BATTERY_VALUE_UNKNOWN &&
 916                 battery->capacity_now >= 0 && battery->capacity_now <= 100) {
 917                 set_bit(ACPI_BATTERY_QUIRK_PERCENTAGE_CAPACITY, &battery->flags);
 918                 battery->full_charge_capacity = battery->design_capacity;
 919                 battery->capacity_now = (battery->capacity_now *
 920                                 battery->full_charge_capacity) / 100;
 921         }
 922
 923         if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH, &battery->flags))
 924                 return;
 925
 926         if (battery->power_unit && dmi_name_in_vendors("LENOVO")) {
 927                 const char *s;
 928
 929                 s = dmi_get_system_info(DMI_PRODUCT_VERSION);
 930                 if (s && !strncasecmp(s, "ThinkPad", 8)) {
 931                         dmi_walk(find_battery, battery);
 932                         if (test_bit(ACPI_BATTERY_QUIRK_THINKPAD_MAH,
 933                                      &battery->flags) &&
 934                             battery->design_voltage) {
 935                                 battery->design_capacity =
 936                                     battery->design_capacity *
 937                                     10000 / battery->design_voltage;
 938                                 battery->full_charge_capacity =
 939                                     battery->full_charge_capacity *
 940                                     10000 / battery->design_voltage;
 941                                 battery->design_capacity_warning =
 942                                     battery->design_capacity_warning *
 943                                     10000 / battery->design_voltage;
 944                                 battery->capacity_now = battery->capacity_now *
 945                                     10000 / battery->design_voltage;
 946                         }
 947                 }
 948         }
 949
 950         if (test_bit(ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE, &battery->flags))
 951                 return;
 952
 953         if (acpi_battery_is_degraded(battery) &&
 954             battery->capacity_now > battery->full_charge_capacity) {
 955                 set_bit(ACPI_BATTERY_QUIRK_DEGRADED_FULL_CHARGE, &battery->flags);
 956                 battery->capacity_now = battery->full_charge_capacity;
 957         }
 958 }
 959
 960 static int acpi_battery_update(struct acpi_battery *battery, bool resume)
 961 {
 962         int result = acpi_battery_get_status(battery);
 963
 964         if (result)
 965                 return result;
 966
 967         if (!acpi_battery_present(battery)) {
 968                 sysfs_remove_battery(battery);
 969                 battery->update_time = 0;
 970                 return 0;
 971         }
 972
 973         if (resume)
 974                 return 0;
 975
 976         if (!battery->update_time) {
 977                 result = acpi_battery_get_info(battery);
 978                 if (result)
 979                         return result;
 980                 acpi_battery_init_alarm(battery);
 981         }
 982
 983         result = acpi_battery_get_state(battery);
 984         if (result)
 985                 return result;
 986         acpi_battery_quirks(battery);
 987
 988         if (!battery->bat) {
 989                 result = sysfs_add_battery(battery);
 990                 if (result)
 991                         return result;
 992         }
 993
 994         /*
 995          * Wakeup the system if battery is critical low
 996          * or lower than the alarm level
 997          */
 998         if ((battery->state & ACPI_BATTERY_STATE_CRITICAL) ||
 999             (test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags) &&
1000              (battery->capacity_now <= battery->alarm)))
1001                 acpi_pm_wakeup_event(&battery->device->dev);
1002
1003         return result;
1004 }
1005
1006 static void acpi_battery_refresh(struct acpi_battery *battery)
1007 {
1008         int power_unit;
1009
1010         if (!battery->bat)
1011                 return;
1012
1013         power_unit = battery->power_unit;
1014
1015         acpi_battery_get_info(battery);
1016
1017         if (power_unit == battery->power_unit)
1018                 return;
1019
1020         /* The battery has changed its reporting units. */
1021         sysfs_remove_battery(battery);
1022         sysfs_add_battery(battery);
1023 }
1024
1025 /* Driver Interface */
1026 static void acpi_battery_notify(struct acpi_device *device, u32 event)
1027 {
1028         struct acpi_battery *battery = acpi_driver_data(device);
1029         struct power_supply *old;
1030
1031         if (!battery)
1032                 return;
1033         old = battery->bat;
1034         /*
1035          * On Acer Aspire V5-573G notifications are sometimes triggered too
1036          * early. For example, when AC is unplugged and notification is
1037          * triggered, battery state is still reported as "Full", and changes to
1038          * "Discharging" only after short delay, without any notification.
1039          */
1040         if (battery_notification_delay_ms > 0)
1041                 msleep(battery_notification_delay_ms);
1042         if (event == ACPI_BATTERY_NOTIFY_INFO)
1043                 acpi_battery_refresh(battery);
1044         acpi_battery_update(battery, false);
1045         acpi_bus_generate_netlink_event(device->pnp.device_class,
1046                                         dev_name(&device->dev), event,
1047                                         acpi_battery_present(battery));
1048         acpi_notifier_call_chain(device, event, acpi_battery_present(battery));
1049         /* acpi_battery_update could remove power_supply object */
1050         if (old && battery->bat)
1051                 power_supply_changed(battery->bat);
1052 }
1053
1054 static int battery_notify(struct notifier_block *nb,
1055                                unsigned long mode, void *_unused)
1056 {
1057         struct acpi_battery *battery = container_of(nb, struct acpi_battery,
1058                                                     pm_nb);
1059         int result;
1060
1061         switch (mode) {
1062         case PM_POST_HIBERNATION:
1063         case PM_POST_SUSPEND:
1064                 if (!acpi_battery_present(battery))
1065                         return 0;
1066
1067                 if (battery->bat) {
1068                         acpi_battery_refresh(battery);
1069                 } else {
1070                         result = acpi_battery_get_info(battery);
1071                         if (result)
1072                                 return result;
1073
1074                         result = sysfs_add_battery(battery);
1075                         if (result)
1076                                 return result;
1077                 }
1078
1079                 acpi_battery_init_alarm(battery);
1080                 acpi_battery_get_state(battery);
1081                 break;
1082         }
1083
1084         return 0;
1085 }
1086
1087 static int __init
1088 battery_bix_broken_package_quirk(const struct dmi_system_id *d)
1089 {
1090         battery_bix_broken_package = 1;
1091         return 0;
1092 }
1093
1094 static int __init
1095 battery_notification_delay_quirk(const struct dmi_system_id *d)
1096 {
1097         battery_notification_delay_ms = 1000;
1098         return 0;
1099 }
1100
1101 static int __init
1102 battery_ac_is_broken_quirk(const struct dmi_system_id *d)
1103 {
1104         battery_ac_is_broken = 1;
1105         return 0;
1106 }
1107
1108 static const struct dmi_system_id bat_dmi_table[] __initconst = {
1109         {
1110                 /* NEC LZ750/LS */
1111                 .callback = battery_bix_broken_package_quirk,
1112                 .matches = {
1113                         DMI_MATCH(DMI_SYS_VENDOR, "NEC"),
1114                         DMI_MATCH(DMI_PRODUCT_NAME, "PC-LZ750LS"),
1115                 },
1116         },
1117         {
1118                 /* Acer Aspire V5-573G */
1119                 .callback = battery_notification_delay_quirk,
1120                 .matches = {
1121                         DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
1122                         DMI_MATCH(DMI_PRODUCT_NAME, "Aspire V5-573G"),
1123                 },
1124         },
1125         {
1126                 /* Point of View mobii wintab p800w */
1127                 .callback = battery_ac_is_broken_quirk,
1128                 .matches = {
1129                         DMI_MATCH(DMI_BOARD_VENDOR, "AMI Corporation"),
1130                         DMI_MATCH(DMI_BOARD_NAME, "Aptio CRB"),
1131                         DMI_MATCH(DMI_BIOS_VERSION, "3BAIR1013"),
1132                         /* Above matches are too generic, add bios-date match */
1133                         DMI_MATCH(DMI_BIOS_DATE, "08/22/2014"),
1134                 },
1135         },
1136         {
1137                 /* Microsoft Surface Go 3 */
1138                 .callback = battery_notification_delay_quirk,
1139                 .matches = {
1140                         DMI_MATCH(DMI_SYS_VENDOR, "Microsoft Corporation"),
1141                         DMI_MATCH(DMI_PRODUCT_NAME, "Surface Go 3"),
1142                 },
1143         },
1144         {},
1145 };
1146
1147 /*
1148  * Some machines'(E,G Lenovo Z480) ECs are not stable
1149  * during boot up and this causes battery driver fails to be
1150  * probed due to failure of getting battery information
1151  * from EC sometimes. After several retries, the operation
1152  * may work. So add retry code here and 20ms sleep between
1153  * every retries.
1154  */
1155 static int acpi_battery_update_retry(struct acpi_battery *battery)
1156 {
1157         int retry, ret;
1158
1159         for (retry = 5; retry; retry--) {
1160                 ret = acpi_battery_update(battery, false);
1161                 if (!ret)
1162                         break;
1163
1164                 msleep(20);
1165         }
1166         return ret;
1167 }
1168
1169 static int acpi_battery_add(struct acpi_device *device)
1170 {
1171         int result = 0;
1172         struct acpi_battery *battery = NULL;
1173
1174         if (!device)
1175                 return -EINVAL;
1176
1177         if (device->dep_unmet)
1178                 return -EPROBE_DEFER;
1179
1180         battery = kzalloc(sizeof(struct acpi_battery), GFP_KERNEL);
1181         if (!battery)
1182                 return -ENOMEM;
1183         battery->device = device;
1184         strcpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
1185         strcpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
1186         device->driver_data = battery;
1187         mutex_init(&battery->lock);
1188         mutex_init(&battery->sysfs_lock);
1189         if (acpi_has_method(battery->device->handle, "_BIX"))
1190                 set_bit(ACPI_BATTERY_XINFO_PRESENT, &battery->flags);
1191
1192         result = acpi_battery_update_retry(battery);
1193         if (result)
1194                 goto fail;
1195
1196         pr_info("Slot [%s] (battery %s)\n", acpi_device_bid(device),
1197                 device->status.battery_present ? "present" : "absent");
1198
1199         battery->pm_nb.notifier_call = battery_notify;
1200         register_pm_notifier(&battery->pm_nb);
1201
1202         device_init_wakeup(&device->dev, 1);
1203
1204         return result;
1205
1206 fail:
1207         sysfs_remove_battery(battery);
1208         mutex_destroy(&battery->lock);
1209         mutex_destroy(&battery->sysfs_lock);
1210         kfree(battery);
1211         return result;
1212 }
1213
1214 static void acpi_battery_remove(struct acpi_device *device)
1215 {
1216         struct acpi_battery *battery = NULL;
1217
1218         if (!device || !acpi_driver_data(device))
1219                 return;
1220         device_init_wakeup(&device->dev, 0);
1221         battery = acpi_driver_data(device);
1222         unregister_pm_notifier(&battery->pm_nb);
1223         sysfs_remove_battery(battery);
1224         mutex_destroy(&battery->lock);
1225         mutex_destroy(&battery->sysfs_lock);
1226         kfree(battery);
1227 }
1228
1229 #ifdef CONFIG_PM_SLEEP
1230 /* this is needed to learn about changes made in suspended state */
1231 static int acpi_battery_resume(struct device *dev)
1232 {
1233         struct acpi_battery *battery;
1234
1235         if (!dev)
1236                 return -EINVAL;
1237
1238         battery = acpi_driver_data(to_acpi_device(dev));
1239         if (!battery)
1240                 return -EINVAL;
1241
1242         battery->update_time = 0;
1243         acpi_battery_update(battery, true);
1244         return 0;
1245 }
1246 #else
1247 #define acpi_battery_resume NULL
1248 #endif
1249
1250 static SIMPLE_DEV_PM_OPS(acpi_battery_pm, NULL, acpi_battery_resume);
1251
1252 static struct acpi_driver acpi_battery_driver = {
1253         .name = "battery",
1254         .class = ACPI_BATTERY_CLASS,
1255         .ids = battery_device_ids,
1256         .flags = ACPI_DRIVER_ALL_NOTIFY_EVENTS,
1257         .ops = {
1258                 .add = acpi_battery_add,
1259                 .remove = acpi_battery_remove,
1260                 .notify = acpi_battery_notify,
1261                 },
1262         .drv.pm = &acpi_battery_pm,
1263 };
1264
1265 static void __init acpi_battery_init_async(void *unused, async_cookie_t cookie)
1266 {
1267         int result;
1268
1269         if (acpi_quirk_skip_acpi_ac_and_battery())
1270                 return;
1271
1272         dmi_check_system(bat_dmi_table);
1273
1274         result = acpi_bus_register_driver(&acpi_battery_driver);
1275         battery_driver_registered = (result == 0);
1276 }
1277
1278 static int __init acpi_battery_init(void)
1279 {
1280         if (acpi_disabled)
1281                 return -ENODEV;
1282
1283         async_cookie = async_schedule(acpi_battery_init_async, NULL);
1284         return 0;
1285 }
1286
1287 static void __exit acpi_battery_exit(void)
1288 {
1289         async_synchronize_cookie(async_cookie + 1);
1290         if (battery_driver_registered) {
1291                 acpi_bus_unregister_driver(&acpi_battery_driver);
1292                 battery_hook_exit();
1293         }
1294 }
1295
1296 module_init(acpi_battery_init);
1297 module_exit(acpi_battery_exit);