drivers/acpi/battery.c

   1 /*
   2  *  battery.c - ACPI Battery Driver (Revision: 2.0)
   3  *
   4  *  Copyright (C) 2007 Alexey Starikovskiy <astarikovskiy@suse.de>
   5  *  Copyright (C) 2004-2007 Vladimir Lebedev <vladimir.p.lebedev@intel.com>
   6  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   7  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   8  *
   9  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  10  *
  11  *  This program is free software; you can redistribute it and/or modify
  12  *  it under the terms of the GNU General Public License as published by
  13  *  the Free Software Foundation; either version 2 of the License, or (at
  14  *  your option) any later version.
  15  *
  16  *  This program is distributed in the hope that it will be useful, but
  17  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  18  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19  *  General Public License for more details.
  20  *
  21  *  You should have received a copy of the GNU General Public License along
  22  *  with this program; if not, write to the Free Software Foundation, Inc.,
  23  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  24  *
  25  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  26  */
  27
  28 #include <linux/kernel.h>
  29 #include <linux/module.h>
  30 #include <linux/init.h>
  31 #include <linux/types.h>
  32 #include <linux/jiffies.h>
  33
  34 #ifdef CONFIG_ACPI_PROCFS_POWER
  35 #include <linux/proc_fs.h>
  36 #include <linux/seq_file.h>
  37 #include <asm/uaccess.h>
  38 #endif
  39
  40 #include <acpi/acpi_bus.h>
  41 #include <acpi/acpi_drivers.h>
  42
  43 #ifdef CONFIG_ACPI_SYSFS_POWER
  44 #include <linux/power_supply.h>
  45 #endif
  46
  47 #define ACPI_BATTERY_VALUE_UNKNOWN 0xFFFFFFFF
  48
  49 #define ACPI_BATTERY_CLASS              "battery"
  50 #define ACPI_BATTERY_DEVICE_NAME        "Battery"
  51 #define ACPI_BATTERY_NOTIFY_STATUS      0x80
  52 #define ACPI_BATTERY_NOTIFY_INFO        0x81
  53
  54 #define _COMPONENT              ACPI_BATTERY_COMPONENT
  55
  56 ACPI_MODULE_NAME("battery");
  57
  58 MODULE_AUTHOR("Paul Diefenbaugh");
  59 MODULE_AUTHOR("Alexey Starikovskiy <astarikovskiy@suse.de>");
  60 MODULE_DESCRIPTION("ACPI Battery Driver");
  61 MODULE_LICENSE("GPL");
  62
  63 static unsigned int cache_time = 1000;
  64 module_param(cache_time, uint, 0644);
  65 MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
  66
  67 #ifdef CONFIG_ACPI_PROCFS_POWER
  68 extern struct proc_dir_entry *acpi_lock_battery_dir(void);
  69 extern void *acpi_unlock_battery_dir(struct proc_dir_entry *acpi_battery_dir);
  70
  71 enum acpi_battery_files {
  72         info_tag = 0,
  73         state_tag,
  74         alarm_tag,
  75         ACPI_BATTERY_NUMFILES,
  76 };
  77
  78 #endif
  79
  80 static const struct acpi_device_id battery_device_ids[] = {
  81         {"PNP0C0A", 0},
  82         {"", 0},
  83 };
  84
  85 MODULE_DEVICE_TABLE(acpi, battery_device_ids);
  86
  87
  88 struct acpi_battery {
  89         struct mutex lock;
  90 #ifdef CONFIG_ACPI_SYSFS_POWER
  91         struct power_supply bat;
  92 #endif
  93         struct acpi_device *device;
  94         unsigned long update_time;
  95         int current_now;
  96         int capacity_now;
  97         int voltage_now;
  98         int design_capacity;
  99         int full_charge_capacity;
 100         int technology;
 101         int design_voltage;
 102         int design_capacity_warning;
 103         int design_capacity_low;
 104         int capacity_granularity_1;
 105         int capacity_granularity_2;
 106         int alarm;
 107         char model_number[32];
 108         char serial_number[32];
 109         char type[32];
 110         char oem_info[32];
 111         int state;
 112         int power_unit;
 113         u8 alarm_present;
 114 };
 115
 116 #define to_acpi_battery(x) container_of(x, struct acpi_battery, bat);
 117
 118 inline int acpi_battery_present(struct acpi_battery *battery)
 119 {
 120         return battery->device->status.battery_present;
 121 }
 122
 123 #ifdef CONFIG_ACPI_SYSFS_POWER
 124 static int acpi_battery_technology(struct acpi_battery *battery)
 125 {
 126         if (!strcasecmp("NiCd", battery->type))
 127                 return POWER_SUPPLY_TECHNOLOGY_NiCd;
 128         if (!strcasecmp("NiMH", battery->type))
 129                 return POWER_SUPPLY_TECHNOLOGY_NiMH;
 130         if (!strcasecmp("LION", battery->type))
 131                 return POWER_SUPPLY_TECHNOLOGY_LION;
 132         if (!strncasecmp("LI-ION", battery->type, 6))
 133                 return POWER_SUPPLY_TECHNOLOGY_LION;
 134         if (!strcasecmp("LiP", battery->type))
 135                 return POWER_SUPPLY_TECHNOLOGY_LIPO;
 136         return POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
 137 }
 138
 139 static int acpi_battery_get_state(struct acpi_battery *battery);
 140
 141 static int acpi_battery_get_property(struct power_supply *psy,
 142                                      enum power_supply_property psp,
 143                                      union power_supply_propval *val)
 144 {
 145         struct acpi_battery *battery = to_acpi_battery(psy);
 146
 147         if (acpi_battery_present(battery)) {
 148                 /* run battery update only if it is present */
 149                 acpi_battery_get_state(battery);
 150         } else if (psp != POWER_SUPPLY_PROP_PRESENT)
 151                 return -ENODEV;
 152         switch (psp) {
 153         case POWER_SUPPLY_PROP_STATUS:
 154                 if (battery->state & 0x01)
 155                         val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
 156                 else if (battery->state & 0x02)
 157                         val->intval = POWER_SUPPLY_STATUS_CHARGING;
 158                 else if (battery->state == 0)
 159                         val->intval = POWER_SUPPLY_STATUS_FULL;
 160                 else
 161                         val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
 162                 break;
 163         case POWER_SUPPLY_PROP_PRESENT:
 164                 val->intval = acpi_battery_present(battery);
 165                 break;
 166         case POWER_SUPPLY_PROP_TECHNOLOGY:
 167                 val->intval = acpi_battery_technology(battery);
 168                 break;
 169         case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
 170                 val->intval = battery->design_voltage * 1000;
 171                 break;
 172         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 173                 val->intval = battery->voltage_now * 1000;
 174                 break;
 175         case POWER_SUPPLY_PROP_CURRENT_NOW:
 176                 val->intval = battery->current_now * 1000;
 177                 break;
 178         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
 179         case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
 180                 val->intval = battery->design_capacity * 1000;
 181                 break;
 182         case POWER_SUPPLY_PROP_CHARGE_FULL:
 183         case POWER_SUPPLY_PROP_ENERGY_FULL:
 184                 val->intval = battery->full_charge_capacity * 1000;
 185                 break;
 186         case POWER_SUPPLY_PROP_CHARGE_NOW:
 187         case POWER_SUPPLY_PROP_ENERGY_NOW:
 188                 val->intval = battery->capacity_now * 1000;
 189                 break;
 190         case POWER_SUPPLY_PROP_MODEL_NAME:
 191                 val->strval = battery->model_number;
 192                 break;
 193         case POWER_SUPPLY_PROP_MANUFACTURER:
 194                 val->strval = battery->oem_info;
 195                 break;
 196         case POWER_SUPPLY_PROP_SERIAL_NUMBER:
 197                 val->strval = battery->serial_number;
 198                 break;
 199         default:
 200                 return -EINVAL;
 201         }
 202         return 0;
 203 }
 204
 205 static enum power_supply_property charge_battery_props[] = {
 206         POWER_SUPPLY_PROP_STATUS,
 207         POWER_SUPPLY_PROP_PRESENT,
 208         POWER_SUPPLY_PROP_TECHNOLOGY,
 209         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 210         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 211         POWER_SUPPLY_PROP_CURRENT_NOW,
 212         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 213         POWER_SUPPLY_PROP_CHARGE_FULL,
 214         POWER_SUPPLY_PROP_CHARGE_NOW,
 215         POWER_SUPPLY_PROP_MODEL_NAME,
 216         POWER_SUPPLY_PROP_MANUFACTURER,
 217         POWER_SUPPLY_PROP_SERIAL_NUMBER,
 218 };
 219
 220 static enum power_supply_property energy_battery_props[] = {
 221         POWER_SUPPLY_PROP_STATUS,
 222         POWER_SUPPLY_PROP_PRESENT,
 223         POWER_SUPPLY_PROP_TECHNOLOGY,
 224         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 225         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 226         POWER_SUPPLY_PROP_CURRENT_NOW,
 227         POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
 228         POWER_SUPPLY_PROP_ENERGY_FULL,
 229         POWER_SUPPLY_PROP_ENERGY_NOW,
 230         POWER_SUPPLY_PROP_MODEL_NAME,
 231         POWER_SUPPLY_PROP_MANUFACTURER,
 232         POWER_SUPPLY_PROP_SERIAL_NUMBER,
 233 };
 234 #endif
 235
 236 #ifdef CONFIG_ACPI_PROCFS_POWER
 237 inline char *acpi_battery_units(struct acpi_battery *battery)
 238 {
 239         return (battery->power_unit)?"mA":"mW";
 240 }
 241 #endif
 242
 243 /* --------------------------------------------------------------------------
 244                                Battery Management
 245    -------------------------------------------------------------------------- */
 246 struct acpi_offsets {
 247         size_t offset;          /* offset inside struct acpi_sbs_battery */
 248         u8 mode;                /* int or string? */
 249 };
 250
 251 static struct acpi_offsets state_offsets[] = {
 252         {offsetof(struct acpi_battery, state), 0},
 253         {offsetof(struct acpi_battery, current_now), 0},
 254         {offsetof(struct acpi_battery, capacity_now), 0},
 255         {offsetof(struct acpi_battery, voltage_now), 0},
 256 };
 257
 258 static struct acpi_offsets info_offsets[] = {
 259         {offsetof(struct acpi_battery, power_unit), 0},
 260         {offsetof(struct acpi_battery, design_capacity), 0},
 261         {offsetof(struct acpi_battery, full_charge_capacity), 0},
 262         {offsetof(struct acpi_battery, technology), 0},
 263         {offsetof(struct acpi_battery, design_voltage), 0},
 264         {offsetof(struct acpi_battery, design_capacity_warning), 0},
 265         {offsetof(struct acpi_battery, design_capacity_low), 0},
 266         {offsetof(struct acpi_battery, capacity_granularity_1), 0},
 267         {offsetof(struct acpi_battery, capacity_granularity_2), 0},
 268         {offsetof(struct acpi_battery, model_number), 1},
 269         {offsetof(struct acpi_battery, serial_number), 1},
 270         {offsetof(struct acpi_battery, type), 1},
 271         {offsetof(struct acpi_battery, oem_info), 1},
 272 };
 273
 274 static int extract_package(struct acpi_battery *battery,
 275                            union acpi_object *package,
 276                            struct acpi_offsets *offsets, int num)
 277 {
 278         int i;
 279         union acpi_object *element;
 280         if (package->type != ACPI_TYPE_PACKAGE)
 281                 return -EFAULT;
 282         for (i = 0; i < num; ++i) {
 283                 if (package->package.count <= i)
 284                         return -EFAULT;
 285                 element = &package->package.elements[i];
 286                 if (offsets[i].mode) {
 287                         u8 *ptr = (u8 *)battery + offsets[i].offset;
 288                         if (element->type == ACPI_TYPE_STRING ||
 289                             element->type == ACPI_TYPE_BUFFER)
 290                                 strncpy(ptr, element->string.pointer, 32);
 291                         else if (element->type == ACPI_TYPE_INTEGER) {
 292                                 strncpy(ptr, (u8 *)&element->integer.value,
 293                                         sizeof(acpi_integer));
 294                                 ptr[sizeof(acpi_integer)] = 0;
 295                         } else
 296                                 *ptr = 0; /* don't have value */
 297                 } else {
 298                         int *x = (int *)((u8 *)battery + offsets[i].offset);
 299                         *x = (element->type == ACPI_TYPE_INTEGER) ?
 300                                 element->integer.value : -1;
 301                 }
 302         }
 303         return 0;
 304 }
 305
 306 static int acpi_battery_get_status(struct acpi_battery *battery)
 307 {
 308         if (acpi_bus_get_status(battery->device)) {
 309                 ACPI_EXCEPTION((AE_INFO, AE_ERROR, "Evaluating _STA"));
 310                 return -ENODEV;
 311         }
 312         return 0;
 313 }
 314
 315 static int acpi_battery_get_info(struct acpi_battery *battery)
 316 {
 317         int result = -EFAULT;
 318         acpi_status status = 0;
 319         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 320
 321         if (!acpi_battery_present(battery))
 322                 return 0;
 323         mutex_lock(&battery->lock);
 324         status = acpi_evaluate_object(battery->device->handle, "_BIF",
 325                                       NULL, &buffer);
 326         mutex_unlock(&battery->lock);
 327
 328         if (ACPI_FAILURE(status)) {
 329                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BIF"));
 330                 return -ENODEV;
 331         }
 332
 333         result = extract_package(battery, buffer.pointer,
 334                                  info_offsets, ARRAY_SIZE(info_offsets));
 335         kfree(buffer.pointer);
 336         return result;
 337 }
 338
 339 static int acpi_battery_get_state(struct acpi_battery *battery)
 340 {
 341         int result = 0;
 342         acpi_status status = 0;
 343         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 344
 345         if (!acpi_battery_present(battery))
 346                 return 0;
 347
 348         if (battery->update_time &&
 349             time_before(jiffies, battery->update_time +
 350                         msecs_to_jiffies(cache_time)))
 351                 return 0;
 352
 353         mutex_lock(&battery->lock);
 354         status = acpi_evaluate_object(battery->device->handle, "_BST",
 355                                       NULL, &buffer);
 356         mutex_unlock(&battery->lock);
 357
 358         if (ACPI_FAILURE(status)) {
 359                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BST"));
 360                 return -ENODEV;
 361         }
 362
 363         result = extract_package(battery, buffer.pointer,
 364                                  state_offsets, ARRAY_SIZE(state_offsets));
 365         battery->update_time = jiffies;
 366         kfree(buffer.pointer);
 367         return result;
 368 }
 369
 370 static int acpi_battery_set_alarm(struct acpi_battery *battery)
 371 {
 372         acpi_status status = 0;
 373         union acpi_object arg0 = { .type = ACPI_TYPE_INTEGER };
 374         struct acpi_object_list arg_list = { 1, &arg0 };
 375
 376         if (!acpi_battery_present(battery)|| !battery->alarm_present)
 377                 return -ENODEV;
 378
 379         arg0.integer.value = battery->alarm;
 380
 381         mutex_lock(&battery->lock);
 382         status = acpi_evaluate_object(battery->device->handle, "_BTP",
 383                                  &arg_list, NULL);
 384         mutex_unlock(&battery->lock);
 385
 386         if (ACPI_FAILURE(status))
 387                 return -ENODEV;
 388
 389         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Alarm set to %d\n", battery->alarm));
 390         return 0;
 391 }
 392
 393 static int acpi_battery_init_alarm(struct acpi_battery *battery)
 394 {
 395         acpi_status status = AE_OK;
 396         acpi_handle handle = NULL;
 397
 398         /* See if alarms are supported, and if so, set default */
 399         status = acpi_get_handle(battery->device->handle, "_BTP", &handle);
 400         if (ACPI_FAILURE(status)) {
 401                 battery->alarm_present = 0;
 402                 return 0;
 403         }
 404         battery->alarm_present = 1;
 405         if (!battery->alarm)
 406                 battery->alarm = battery->design_capacity_warning;
 407         return acpi_battery_set_alarm(battery);
 408 }
 409
 410 #ifdef CONFIG_ACPI_SYSFS_POWER
 411 static ssize_t acpi_battery_alarm_show(struct device *dev,
 412                                         struct device_attribute *attr,
 413                                         char *buf)
 414 {
 415         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
 416         return sprintf(buf, "%d\n", battery->alarm * 1000);
 417 }
 418
 419 static ssize_t acpi_battery_alarm_store(struct device *dev,
 420                                         struct device_attribute *attr,
 421                                         const char *buf, size_t count)
 422 {
 423         unsigned long x;
 424         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
 425         if (sscanf(buf, "%ld\n", &x) == 1)
 426                 battery->alarm = x/1000;
 427         if (acpi_battery_present(battery))
 428                 acpi_battery_set_alarm(battery);
 429         return count;
 430 }
 431
 432 static struct device_attribute alarm_attr = {
 433         .attr = {.name = "alarm", .mode = 0644},
 434         .show = acpi_battery_alarm_show,
 435         .store = acpi_battery_alarm_store,
 436 };
 437
 438 static int sysfs_add_battery(struct acpi_battery *battery)
 439 {
 440         int result;
 441
 442         if (battery->power_unit) {
 443                 battery->bat.properties = charge_battery_props;
 444                 battery->bat.num_properties =
 445                         ARRAY_SIZE(charge_battery_props);
 446         } else {
 447                 battery->bat.properties = energy_battery_props;
 448                 battery->bat.num_properties =
 449                         ARRAY_SIZE(energy_battery_props);
 450         }
 451
 452         battery->bat.name = acpi_device_bid(battery->device);
 453         battery->bat.type = POWER_SUPPLY_TYPE_BATTERY;
 454         battery->bat.get_property = acpi_battery_get_property;
 455
 456         result = power_supply_register(&battery->device->dev, &battery->bat);
 457         if (result)
 458                 return result;
 459         return device_create_file(battery->bat.dev, &alarm_attr);
 460 }
 461
 462 static void sysfs_remove_battery(struct acpi_battery *battery)
 463 {
 464         if (!battery->bat.dev)
 465                 return;
 466         device_remove_file(battery->bat.dev, &alarm_attr);
 467         power_supply_unregister(&battery->bat);
 468         battery->bat.dev = NULL;
 469 }
 470 #endif
 471
 472 static int acpi_battery_update(struct acpi_battery *battery)
 473 {
 474         int result;
 475         result = acpi_battery_get_status(battery);
 476         if (result)
 477                 return result;
 478 #ifdef CONFIG_ACPI_SYSFS_POWER
 479         if (!acpi_battery_present(battery)) {
 480                 sysfs_remove_battery(battery);
 481                 battery->update_time = 0;
 482                 return 0;
 483         }
 484 #endif
 485         if (!battery->update_time) {
 486                 result = acpi_battery_get_info(battery);
 487                 if (result)
 488                         return result;
 489                 acpi_battery_init_alarm(battery);
 490         }
 491 #ifdef CONFIG_ACPI_SYSFS_POWER
 492         if (!battery->bat.dev)
 493                 sysfs_add_battery(battery);
 494 #endif
 495         return acpi_battery_get_state(battery);
 496 }
 497
 498 /* --------------------------------------------------------------------------
 499                               FS Interface (/proc)
 500    -------------------------------------------------------------------------- */
 501
 502 #ifdef CONFIG_ACPI_PROCFS_POWER
 503 static struct proc_dir_entry *acpi_battery_dir;
 504
 505 static int acpi_battery_print_info(struct seq_file *seq, int result)
 506 {
 507         struct acpi_battery *battery = seq->private;
 508
 509         if (result)
 510                 goto end;
 511
 512         seq_printf(seq, "present:                 %s\n",
 513                    acpi_battery_present(battery)?"yes":"no");
 514         if (!acpi_battery_present(battery))
 515                 goto end;
 516         if (battery->design_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
 517                 seq_printf(seq, "design capacity:         unknown\n");
 518         else
 519                 seq_printf(seq, "design capacity:         %d %sh\n",
 520                            battery->design_capacity,
 521                            acpi_battery_units(battery));
 522
 523         if (battery->full_charge_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
 524                 seq_printf(seq, "last full capacity:      unknown\n");
 525         else
 526                 seq_printf(seq, "last full capacity:      %d %sh\n",
 527                            battery->full_charge_capacity,
 528                            acpi_battery_units(battery));
 529
 530         seq_printf(seq, "battery technology:      %srechargeable\n",
 531                    (!battery->technology)?"non-":"");
 532
 533         if (battery->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
 534                 seq_printf(seq, "design voltage:          unknown\n");
 535         else
 536                 seq_printf(seq, "design voltage:          %d mV\n",
 537                            battery->design_voltage);
 538         seq_printf(seq, "design capacity warning: %d %sh\n",
 539                    battery->design_capacity_warning,
 540                    acpi_battery_units(battery));
 541         seq_printf(seq, "design capacity low:     %d %sh\n",
 542                    battery->design_capacity_low,
 543                    acpi_battery_units(battery));
 544         seq_printf(seq, "capacity granularity 1:  %d %sh\n",
 545                    battery->capacity_granularity_1,
 546                    acpi_battery_units(battery));
 547         seq_printf(seq, "capacity granularity 2:  %d %sh\n",
 548                    battery->capacity_granularity_2,
 549                    acpi_battery_units(battery));
 550         seq_printf(seq, "model number:            %s\n", battery->model_number);
 551         seq_printf(seq, "serial number:           %s\n", battery->serial_number);
 552         seq_printf(seq, "battery type:            %s\n", battery->type);
 553         seq_printf(seq, "OEM info:                %s\n", battery->oem_info);
 554       end:
 555         if (result)
 556                 seq_printf(seq, "ERROR: Unable to read battery info\n");
 557         return result;
 558 }
 559
 560 static int acpi_battery_print_state(struct seq_file *seq, int result)
 561 {
 562         struct acpi_battery *battery = seq->private;
 563
 564         if (result)
 565                 goto end;
 566
 567         seq_printf(seq, "present:                 %s\n",
 568                    acpi_battery_present(battery)?"yes":"no");
 569         if (!acpi_battery_present(battery))
 570                 goto end;
 571
 572         seq_printf(seq, "capacity state:          %s\n",
 573                         (battery->state & 0x04)?"critical":"ok");
 574         if ((battery->state & 0x01) && (battery->state & 0x02))
 575                 seq_printf(seq,
 576                            "charging state:          charging/discharging\n");
 577         else if (battery->state & 0x01)
 578                 seq_printf(seq, "charging state:          discharging\n");
 579         else if (battery->state & 0x02)
 580                 seq_printf(seq, "charging state:          charging\n");
 581         else
 582                 seq_printf(seq, "charging state:          charged\n");
 583
 584         if (battery->current_now == ACPI_BATTERY_VALUE_UNKNOWN)
 585                 seq_printf(seq, "present rate:            unknown\n");
 586         else
 587                 seq_printf(seq, "present rate:            %d %s\n",
 588                            battery->current_now, acpi_battery_units(battery));
 589
 590         if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN)
 591                 seq_printf(seq, "remaining capacity:      unknown\n");
 592         else
 593                 seq_printf(seq, "remaining capacity:      %d %sh\n",
 594                            battery->capacity_now, acpi_battery_units(battery));
 595         if (battery->voltage_now == ACPI_BATTERY_VALUE_UNKNOWN)
 596                 seq_printf(seq, "present voltage:         unknown\n");
 597         else
 598                 seq_printf(seq, "present voltage:         %d mV\n",
 599                            battery->voltage_now);
 600       end:
 601         if (result)
 602                 seq_printf(seq, "ERROR: Unable to read battery state\n");
 603
 604         return result;
 605 }
 606
 607 static int acpi_battery_print_alarm(struct seq_file *seq, int result)
 608 {
 609         struct acpi_battery *battery = seq->private;
 610
 611         if (result)
 612                 goto end;
 613
 614         if (!acpi_battery_present(battery)) {
 615                 seq_printf(seq, "present:                 no\n");
 616                 goto end;
 617         }
 618         seq_printf(seq, "alarm:                   ");
 619         if (!battery->alarm)
 620                 seq_printf(seq, "unsupported\n");
 621         else
 622                 seq_printf(seq, "%u %sh\n", battery->alarm,
 623                                 acpi_battery_units(battery));
 624       end:
 625         if (result)
 626                 seq_printf(seq, "ERROR: Unable to read battery alarm\n");
 627         return result;
 628 }
 629
 630 static ssize_t acpi_battery_write_alarm(struct file *file,
 631                                         const char __user * buffer,
 632                                         size_t count, loff_t * ppos)
 633 {
 634         int result = 0;
 635         char alarm_string[12] = { '\0' };
 636         struct seq_file *m = file->private_data;
 637         struct acpi_battery *battery = m->private;
 638
 639         if (!battery || (count > sizeof(alarm_string) - 1))
 640                 return -EINVAL;
 641         if (!acpi_battery_present(battery)) {
 642                 result = -ENODEV;
 643                 goto end;
 644         }
 645         if (copy_from_user(alarm_string, buffer, count)) {
 646                 result = -EFAULT;
 647                 goto end;
 648         }
 649         alarm_string[count] = '\0';
 650         battery->alarm = simple_strtol(alarm_string, NULL, 0);
 651         result = acpi_battery_set_alarm(battery);
 652       end:
 653         if (!result)
 654                 return count;
 655         return result;
 656 }
 657
 658 typedef int(*print_func)(struct seq_file *seq, int result);
 659
 660 static print_func acpi_print_funcs[ACPI_BATTERY_NUMFILES] = {
 661         acpi_battery_print_info,
 662         acpi_battery_print_state,
 663         acpi_battery_print_alarm,
 664 };
 665
 666 static int acpi_battery_read(int fid, struct seq_file *seq)
 667 {
 668         struct acpi_battery *battery = seq->private;
 669         int result = acpi_battery_update(battery);
 670         return acpi_print_funcs[fid](seq, result);
 671 }
 672
 673 #define DECLARE_FILE_FUNCTIONS(_name) \
 674 static int acpi_battery_read_##_name(struct seq_file *seq, void *offset) \
 675 { \
 676         return acpi_battery_read(_name##_tag, seq); \
 677 } \
 678 static int acpi_battery_##_name##_open_fs(struct inode *inode, struct file *file) \
 679 { \
 680         return single_open(file, acpi_battery_read_##_name, PDE(inode)->data); \
 681 }
 682
 683 DECLARE_FILE_FUNCTIONS(info);
 684 DECLARE_FILE_FUNCTIONS(state);
 685 DECLARE_FILE_FUNCTIONS(alarm);
 686
 687 #undef DECLARE_FILE_FUNCTIONS
 688
 689 #define FILE_DESCRIPTION_RO(_name) \
 690         { \
 691         .name = __stringify(_name), \
 692         .mode = S_IRUGO, \
 693         .ops = { \
 694                 .open = acpi_battery_##_name##_open_fs, \
 695                 .read = seq_read, \
 696                 .llseek = seq_lseek, \
 697                 .release = single_release, \
 698                 .owner = THIS_MODULE, \
 699                 }, \
 700         }
 701
 702 #define FILE_DESCRIPTION_RW(_name) \
 703         { \
 704         .name = __stringify(_name), \
 705         .mode = S_IFREG | S_IRUGO | S_IWUSR, \
 706         .ops = { \
 707                 .open = acpi_battery_##_name##_open_fs, \
 708                 .read = seq_read, \
 709                 .llseek = seq_lseek, \
 710                 .write = acpi_battery_write_##_name, \
 711                 .release = single_release, \
 712                 .owner = THIS_MODULE, \
 713                 }, \
 714         }
 715
 716 static struct battery_file {
 717         struct file_operations ops;
 718         mode_t mode;
 719         char *name;
 720 } acpi_battery_file[] = {
 721         FILE_DESCRIPTION_RO(info),
 722         FILE_DESCRIPTION_RO(state),
 723         FILE_DESCRIPTION_RW(alarm),
 724 };
 725
 726 #undef FILE_DESCRIPTION_RO
 727 #undef FILE_DESCRIPTION_RW
 728
 729 static int acpi_battery_add_fs(struct acpi_device *device)
 730 {
 731         struct proc_dir_entry *entry = NULL;
 732         int i;
 733
 734         if (!acpi_device_dir(device)) {
 735                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 736                                                      acpi_battery_dir);
 737                 if (!acpi_device_dir(device))
 738                         return -ENODEV;
 739                 acpi_device_dir(device)->owner = THIS_MODULE;
 740         }
 741
 742         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i) {
 743                 entry = proc_create_data(acpi_battery_file[i].name,
 744                                          acpi_battery_file[i].mode,
 745                                          acpi_device_dir(device),
 746                                          &acpi_battery_file[i].ops,
 747                                          acpi_driver_data(device));
 748                 if (!entry)
 749                         return -ENODEV;
 750         }
 751         return 0;
 752 }
 753
 754 static void acpi_battery_remove_fs(struct acpi_device *device)
 755 {
 756         int i;
 757         if (!acpi_device_dir(device))
 758                 return;
 759         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i)
 760                 remove_proc_entry(acpi_battery_file[i].name,
 761                                   acpi_device_dir(device));
 762
 763         remove_proc_entry(acpi_device_bid(device), acpi_battery_dir);
 764         acpi_device_dir(device) = NULL;
 765 }
 766
 767 #endif
 768
 769 /* --------------------------------------------------------------------------
 770                                  Driver Interface
 771    -------------------------------------------------------------------------- */
 772
 773 static void acpi_battery_notify(acpi_handle handle, u32 event, void *data)
 774 {
 775         struct acpi_battery *battery = data;
 776         struct acpi_device *device;
 777         if (!battery)
 778                 return;
 779         device = battery->device;
 780         acpi_battery_update(battery);
 781         acpi_bus_generate_proc_event(device, event,
 782                                      acpi_battery_present(battery));
 783         acpi_bus_generate_netlink_event(device->pnp.device_class,
 784                                         dev_name(&device->dev), event,
 785                                         acpi_battery_present(battery));
 786 #ifdef CONFIG_ACPI_SYSFS_POWER
 787         /* acpi_batter_update could remove power_supply object */
 788         if (battery->bat.dev)
 789                 kobject_uevent(&battery->bat.dev->kobj, KOBJ_CHANGE);
 790 #endif
 791 }
 792
 793 static int acpi_battery_add(struct acpi_device *device)
 794 {
 795         int result = 0;
 796         acpi_status status = 0;
 797         struct acpi_battery *battery = NULL;
 798         if (!device)
 799                 return -EINVAL;
 800         battery = kzalloc(sizeof(struct acpi_battery), GFP_KERNEL);
 801         if (!battery)
 802                 return -ENOMEM;
 803         battery->device = device;
 804         strcpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
 805         strcpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
 806         device->driver_data = battery;
 807         mutex_init(&battery->lock);
 808         acpi_battery_update(battery);
 809 #ifdef CONFIG_ACPI_PROCFS_POWER
 810         result = acpi_battery_add_fs(device);
 811         if (result)
 812                 goto end;
 813 #endif
 814         status = acpi_install_notify_handler(device->handle,
 815                                              ACPI_ALL_NOTIFY,
 816                                              acpi_battery_notify, battery);
 817         if (ACPI_FAILURE(status)) {
 818                 ACPI_EXCEPTION((AE_INFO, status, "Installing notify handler"));
 819                 result = -ENODEV;
 820                 goto end;
 821         }
 822         printk(KERN_INFO PREFIX "%s Slot [%s] (battery %s)\n",
 823                ACPI_BATTERY_DEVICE_NAME, acpi_device_bid(device),
 824                device->status.battery_present ? "present" : "absent");
 825       end:
 826         if (result) {
 827 #ifdef CONFIG_ACPI_PROCFS_POWER
 828                 acpi_battery_remove_fs(device);
 829 #endif
 830                 kfree(battery);
 831         }
 832         return result;
 833 }
 834
 835 static int acpi_battery_remove(struct acpi_device *device, int type)
 836 {
 837         acpi_status status = 0;
 838         struct acpi_battery *battery = NULL;
 839
 840         if (!device || !acpi_driver_data(device))
 841                 return -EINVAL;
 842         battery = acpi_driver_data(device);
 843         status = acpi_remove_notify_handler(device->handle,
 844                                             ACPI_ALL_NOTIFY,
 845                                             acpi_battery_notify);
 846 #ifdef CONFIG_ACPI_PROCFS_POWER
 847         acpi_battery_remove_fs(device);
 848 #endif
 849 #ifdef CONFIG_ACPI_SYSFS_POWER
 850         sysfs_remove_battery(battery);
 851 #endif
 852         mutex_destroy(&battery->lock);
 853         kfree(battery);
 854         return 0;
 855 }
 856
 857 /* this is needed to learn about changes made in suspended state */
 858 static int acpi_battery_resume(struct acpi_device *device)
 859 {
 860         struct acpi_battery *battery;
 861         if (!device)
 862                 return -EINVAL;
 863         battery = acpi_driver_data(device);
 864         battery->update_time = 0;
 865         acpi_battery_update(battery);
 866         return 0;
 867 }
 868
 869 static struct acpi_driver acpi_battery_driver = {
 870         .name = "battery",
 871         .class = ACPI_BATTERY_CLASS,
 872         .ids = battery_device_ids,
 873         .ops = {
 874                 .add = acpi_battery_add,
 875                 .resume = acpi_battery_resume,
 876                 .remove = acpi_battery_remove,
 877                 },
 878 };
 879
 880 static int __init acpi_battery_init(void)
 881 {
 882         if (acpi_disabled)
 883                 return -ENODEV;
 884 #ifdef CONFIG_ACPI_PROCFS_POWER
 885         acpi_battery_dir = acpi_lock_battery_dir();
 886         if (!acpi_battery_dir)
 887                 return -ENODEV;
 888 #endif
 889         if (acpi_bus_register_driver(&acpi_battery_driver) < 0) {
 890 #ifdef CONFIG_ACPI_PROCFS_POWER
 891                 acpi_unlock_battery_dir(acpi_battery_dir);
 892 #endif
 893                 return -ENODEV;
 894         }
 895         return 0;
 896 }
 897
 898 static void __exit acpi_battery_exit(void)
 899 {
 900         acpi_bus_unregister_driver(&acpi_battery_driver);
 901 #ifdef CONFIG_ACPI_PROCFS_POWER
 902         acpi_unlock_battery_dir(acpi_battery_dir);
 903 #endif
 904 }
 905
 906 module_init(acpi_battery_init);
 907 module_exit(acpi_battery_exit);