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;
 177                 if (battery->power_unit) {
 178                         val->intval *= 1000;
 179                 } else {
 180                         /*
 181                          * If power units are mW, convert to mA by dividing by
 182                          * current voltage.
 183                          */
 184                         if (battery->voltage_now)
 185                                 val->intval /= battery->voltage_now;
 186                         else
 187                                 val->intval = -1;
 188                 }
 189                 break;
 190         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
 191         case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
 192                 val->intval = battery->design_capacity * 1000;
 193                 break;
 194         case POWER_SUPPLY_PROP_CHARGE_FULL:
 195         case POWER_SUPPLY_PROP_ENERGY_FULL:
 196                 val->intval = battery->full_charge_capacity * 1000;
 197                 break;
 198         case POWER_SUPPLY_PROP_CHARGE_NOW:
 199         case POWER_SUPPLY_PROP_ENERGY_NOW:
 200                 val->intval = battery->capacity_now * 1000;
 201                 break;
 202         case POWER_SUPPLY_PROP_MODEL_NAME:
 203                 val->strval = battery->model_number;
 204                 break;
 205         case POWER_SUPPLY_PROP_MANUFACTURER:
 206                 val->strval = battery->oem_info;
 207                 break;
 208         case POWER_SUPPLY_PROP_SERIAL_NUMBER:
 209                 val->strval = battery->serial_number;
 210                 break;
 211         default:
 212                 return -EINVAL;
 213         }
 214         return 0;
 215 }
 216
 217 static enum power_supply_property charge_battery_props[] = {
 218         POWER_SUPPLY_PROP_STATUS,
 219         POWER_SUPPLY_PROP_PRESENT,
 220         POWER_SUPPLY_PROP_TECHNOLOGY,
 221         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 222         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 223         POWER_SUPPLY_PROP_CURRENT_NOW,
 224         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 225         POWER_SUPPLY_PROP_CHARGE_FULL,
 226         POWER_SUPPLY_PROP_CHARGE_NOW,
 227         POWER_SUPPLY_PROP_MODEL_NAME,
 228         POWER_SUPPLY_PROP_MANUFACTURER,
 229         POWER_SUPPLY_PROP_SERIAL_NUMBER,
 230 };
 231
 232 static enum power_supply_property energy_battery_props[] = {
 233         POWER_SUPPLY_PROP_STATUS,
 234         POWER_SUPPLY_PROP_PRESENT,
 235         POWER_SUPPLY_PROP_TECHNOLOGY,
 236         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 237         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 238         POWER_SUPPLY_PROP_CURRENT_NOW,
 239         POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
 240         POWER_SUPPLY_PROP_ENERGY_FULL,
 241         POWER_SUPPLY_PROP_ENERGY_NOW,
 242         POWER_SUPPLY_PROP_MODEL_NAME,
 243         POWER_SUPPLY_PROP_MANUFACTURER,
 244         POWER_SUPPLY_PROP_SERIAL_NUMBER,
 245 };
 246 #endif
 247
 248 #ifdef CONFIG_ACPI_PROCFS_POWER
 249 inline char *acpi_battery_units(struct acpi_battery *battery)
 250 {
 251         return (battery->power_unit)?"mA":"mW";
 252 }
 253 #endif
 254
 255 /* --------------------------------------------------------------------------
 256                                Battery Management
 257    -------------------------------------------------------------------------- */
 258 struct acpi_offsets {
 259         size_t offset;          /* offset inside struct acpi_sbs_battery */
 260         u8 mode;                /* int or string? */
 261 };
 262
 263 static struct acpi_offsets state_offsets[] = {
 264         {offsetof(struct acpi_battery, state), 0},
 265         {offsetof(struct acpi_battery, current_now), 0},
 266         {offsetof(struct acpi_battery, capacity_now), 0},
 267         {offsetof(struct acpi_battery, voltage_now), 0},
 268 };
 269
 270 static struct acpi_offsets info_offsets[] = {
 271         {offsetof(struct acpi_battery, power_unit), 0},
 272         {offsetof(struct acpi_battery, design_capacity), 0},
 273         {offsetof(struct acpi_battery, full_charge_capacity), 0},
 274         {offsetof(struct acpi_battery, technology), 0},
 275         {offsetof(struct acpi_battery, design_voltage), 0},
 276         {offsetof(struct acpi_battery, design_capacity_warning), 0},
 277         {offsetof(struct acpi_battery, design_capacity_low), 0},
 278         {offsetof(struct acpi_battery, capacity_granularity_1), 0},
 279         {offsetof(struct acpi_battery, capacity_granularity_2), 0},
 280         {offsetof(struct acpi_battery, model_number), 1},
 281         {offsetof(struct acpi_battery, serial_number), 1},
 282         {offsetof(struct acpi_battery, type), 1},
 283         {offsetof(struct acpi_battery, oem_info), 1},
 284 };
 285
 286 static int extract_package(struct acpi_battery *battery,
 287                            union acpi_object *package,
 288                            struct acpi_offsets *offsets, int num)
 289 {
 290         int i;
 291         union acpi_object *element;
 292         if (package->type != ACPI_TYPE_PACKAGE)
 293                 return -EFAULT;
 294         for (i = 0; i < num; ++i) {
 295                 if (package->package.count <= i)
 296                         return -EFAULT;
 297                 element = &package->package.elements[i];
 298                 if (offsets[i].mode) {
 299                         u8 *ptr = (u8 *)battery + offsets[i].offset;
 300                         if (element->type == ACPI_TYPE_STRING ||
 301                             element->type == ACPI_TYPE_BUFFER)
 302                                 strncpy(ptr, element->string.pointer, 32);
 303                         else if (element->type == ACPI_TYPE_INTEGER) {
 304                                 strncpy(ptr, (u8 *)&element->integer.value,
 305                                         sizeof(acpi_integer));
 306                                 ptr[sizeof(acpi_integer)] = 0;
 307                         } else
 308                                 *ptr = 0; /* don't have value */
 309                 } else {
 310                         int *x = (int *)((u8 *)battery + offsets[i].offset);
 311                         *x = (element->type == ACPI_TYPE_INTEGER) ?
 312                                 element->integer.value : -1;
 313                 }
 314         }
 315         return 0;
 316 }
 317
 318 static int acpi_battery_get_status(struct acpi_battery *battery)
 319 {
 320         if (acpi_bus_get_status(battery->device)) {
 321                 ACPI_EXCEPTION((AE_INFO, AE_ERROR, "Evaluating _STA"));
 322                 return -ENODEV;
 323         }
 324         return 0;
 325 }
 326
 327 static int acpi_battery_get_info(struct acpi_battery *battery)
 328 {
 329         int result = -EFAULT;
 330         acpi_status status = 0;
 331         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 332
 333         if (!acpi_battery_present(battery))
 334                 return 0;
 335         mutex_lock(&battery->lock);
 336         status = acpi_evaluate_object(battery->device->handle, "_BIF",
 337                                       NULL, &buffer);
 338         mutex_unlock(&battery->lock);
 339
 340         if (ACPI_FAILURE(status)) {
 341                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BIF"));
 342                 return -ENODEV;
 343         }
 344
 345         result = extract_package(battery, buffer.pointer,
 346                                  info_offsets, ARRAY_SIZE(info_offsets));
 347         kfree(buffer.pointer);
 348         return result;
 349 }
 350
 351 static int acpi_battery_get_state(struct acpi_battery *battery)
 352 {
 353         int result = 0;
 354         acpi_status status = 0;
 355         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 356
 357         if (!acpi_battery_present(battery))
 358                 return 0;
 359
 360         if (battery->update_time &&
 361             time_before(jiffies, battery->update_time +
 362                         msecs_to_jiffies(cache_time)))
 363                 return 0;
 364
 365         mutex_lock(&battery->lock);
 366         status = acpi_evaluate_object(battery->device->handle, "_BST",
 367                                       NULL, &buffer);
 368         mutex_unlock(&battery->lock);
 369
 370         if (ACPI_FAILURE(status)) {
 371                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BST"));
 372                 return -ENODEV;
 373         }
 374
 375         result = extract_package(battery, buffer.pointer,
 376                                  state_offsets, ARRAY_SIZE(state_offsets));
 377         battery->update_time = jiffies;
 378         kfree(buffer.pointer);
 379         return result;
 380 }
 381
 382 static int acpi_battery_set_alarm(struct acpi_battery *battery)
 383 {
 384         acpi_status status = 0;
 385         union acpi_object arg0 = { .type = ACPI_TYPE_INTEGER };
 386         struct acpi_object_list arg_list = { 1, &arg0 };
 387
 388         if (!acpi_battery_present(battery)|| !battery->alarm_present)
 389                 return -ENODEV;
 390
 391         arg0.integer.value = battery->alarm;
 392
 393         mutex_lock(&battery->lock);
 394         status = acpi_evaluate_object(battery->device->handle, "_BTP",
 395                                  &arg_list, NULL);
 396         mutex_unlock(&battery->lock);
 397
 398         if (ACPI_FAILURE(status))
 399                 return -ENODEV;
 400
 401         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Alarm set to %d\n", battery->alarm));
 402         return 0;
 403 }
 404
 405 static int acpi_battery_init_alarm(struct acpi_battery *battery)
 406 {
 407         acpi_status status = AE_OK;
 408         acpi_handle handle = NULL;
 409
 410         /* See if alarms are supported, and if so, set default */
 411         status = acpi_get_handle(battery->device->handle, "_BTP", &handle);
 412         if (ACPI_FAILURE(status)) {
 413                 battery->alarm_present = 0;
 414                 return 0;
 415         }
 416         battery->alarm_present = 1;
 417         if (!battery->alarm)
 418                 battery->alarm = battery->design_capacity_warning;
 419         return acpi_battery_set_alarm(battery);
 420 }
 421
 422 #ifdef CONFIG_ACPI_SYSFS_POWER
 423 static ssize_t acpi_battery_alarm_show(struct device *dev,
 424                                         struct device_attribute *attr,
 425                                         char *buf)
 426 {
 427         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
 428         return sprintf(buf, "%d\n", battery->alarm * 1000);
 429 }
 430
 431 static ssize_t acpi_battery_alarm_store(struct device *dev,
 432                                         struct device_attribute *attr,
 433                                         const char *buf, size_t count)
 434 {
 435         unsigned long x;
 436         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
 437         if (sscanf(buf, "%ld\n", &x) == 1)
 438                 battery->alarm = x/1000;
 439         if (acpi_battery_present(battery))
 440                 acpi_battery_set_alarm(battery);
 441         return count;
 442 }
 443
 444 static struct device_attribute alarm_attr = {
 445         .attr = {.name = "alarm", .mode = 0644},
 446         .show = acpi_battery_alarm_show,
 447         .store = acpi_battery_alarm_store,
 448 };
 449
 450 static int sysfs_add_battery(struct acpi_battery *battery)
 451 {
 452         int result;
 453
 454         if (battery->power_unit) {
 455                 battery->bat.properties = charge_battery_props;
 456                 battery->bat.num_properties =
 457                         ARRAY_SIZE(charge_battery_props);
 458         } else {
 459                 battery->bat.properties = energy_battery_props;
 460                 battery->bat.num_properties =
 461                         ARRAY_SIZE(energy_battery_props);
 462         }
 463
 464         battery->bat.name = acpi_device_bid(battery->device);
 465         battery->bat.type = POWER_SUPPLY_TYPE_BATTERY;
 466         battery->bat.get_property = acpi_battery_get_property;
 467
 468         result = power_supply_register(&battery->device->dev, &battery->bat);
 469         if (result)
 470                 return result;
 471         return device_create_file(battery->bat.dev, &alarm_attr);
 472 }
 473
 474 static void sysfs_remove_battery(struct acpi_battery *battery)
 475 {
 476         if (!battery->bat.dev)
 477                 return;
 478         device_remove_file(battery->bat.dev, &alarm_attr);
 479         power_supply_unregister(&battery->bat);
 480         battery->bat.dev = NULL;
 481 }
 482 #endif
 483
 484 static int acpi_battery_update(struct acpi_battery *battery)
 485 {
 486         int result;
 487         result = acpi_battery_get_status(battery);
 488         if (result)
 489                 return result;
 490 #ifdef CONFIG_ACPI_SYSFS_POWER
 491         if (!acpi_battery_present(battery)) {
 492                 sysfs_remove_battery(battery);
 493                 battery->update_time = 0;
 494                 return 0;
 495         }
 496 #endif
 497         if (!battery->update_time) {
 498                 result = acpi_battery_get_info(battery);
 499                 if (result)
 500                         return result;
 501                 acpi_battery_init_alarm(battery);
 502         }
 503 #ifdef CONFIG_ACPI_SYSFS_POWER
 504         if (!battery->bat.dev)
 505                 sysfs_add_battery(battery);
 506 #endif
 507         return acpi_battery_get_state(battery);
 508 }
 509
 510 /* --------------------------------------------------------------------------
 511                               FS Interface (/proc)
 512    -------------------------------------------------------------------------- */
 513
 514 #ifdef CONFIG_ACPI_PROCFS_POWER
 515 static struct proc_dir_entry *acpi_battery_dir;
 516
 517 static int acpi_battery_print_info(struct seq_file *seq, int result)
 518 {
 519         struct acpi_battery *battery = seq->private;
 520
 521         if (result)
 522                 goto end;
 523
 524         seq_printf(seq, "present:                 %s\n",
 525                    acpi_battery_present(battery)?"yes":"no");
 526         if (!acpi_battery_present(battery))
 527                 goto end;
 528         if (battery->design_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
 529                 seq_printf(seq, "design capacity:         unknown\n");
 530         else
 531                 seq_printf(seq, "design capacity:         %d %sh\n",
 532                            battery->design_capacity,
 533                            acpi_battery_units(battery));
 534
 535         if (battery->full_charge_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
 536                 seq_printf(seq, "last full capacity:      unknown\n");
 537         else
 538                 seq_printf(seq, "last full capacity:      %d %sh\n",
 539                            battery->full_charge_capacity,
 540                            acpi_battery_units(battery));
 541
 542         seq_printf(seq, "battery technology:      %srechargeable\n",
 543                    (!battery->technology)?"non-":"");
 544
 545         if (battery->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
 546                 seq_printf(seq, "design voltage:          unknown\n");
 547         else
 548                 seq_printf(seq, "design voltage:          %d mV\n",
 549                            battery->design_voltage);
 550         seq_printf(seq, "design capacity warning: %d %sh\n",
 551                    battery->design_capacity_warning,
 552                    acpi_battery_units(battery));
 553         seq_printf(seq, "design capacity low:     %d %sh\n",
 554                    battery->design_capacity_low,
 555                    acpi_battery_units(battery));
 556         seq_printf(seq, "capacity granularity 1:  %d %sh\n",
 557                    battery->capacity_granularity_1,
 558                    acpi_battery_units(battery));
 559         seq_printf(seq, "capacity granularity 2:  %d %sh\n",
 560                    battery->capacity_granularity_2,
 561                    acpi_battery_units(battery));
 562         seq_printf(seq, "model number:            %s\n", battery->model_number);
 563         seq_printf(seq, "serial number:           %s\n", battery->serial_number);
 564         seq_printf(seq, "battery type:            %s\n", battery->type);
 565         seq_printf(seq, "OEM info:                %s\n", battery->oem_info);
 566       end:
 567         if (result)
 568                 seq_printf(seq, "ERROR: Unable to read battery info\n");
 569         return result;
 570 }
 571
 572 static int acpi_battery_print_state(struct seq_file *seq, int result)
 573 {
 574         struct acpi_battery *battery = seq->private;
 575
 576         if (result)
 577                 goto end;
 578
 579         seq_printf(seq, "present:                 %s\n",
 580                    acpi_battery_present(battery)?"yes":"no");
 581         if (!acpi_battery_present(battery))
 582                 goto end;
 583
 584         seq_printf(seq, "capacity state:          %s\n",
 585                         (battery->state & 0x04)?"critical":"ok");
 586         if ((battery->state & 0x01) && (battery->state & 0x02))
 587                 seq_printf(seq,
 588                            "charging state:          charging/discharging\n");
 589         else if (battery->state & 0x01)
 590                 seq_printf(seq, "charging state:          discharging\n");
 591         else if (battery->state & 0x02)
 592                 seq_printf(seq, "charging state:          charging\n");
 593         else
 594                 seq_printf(seq, "charging state:          charged\n");
 595
 596         if (battery->current_now == ACPI_BATTERY_VALUE_UNKNOWN)
 597                 seq_printf(seq, "present rate:            unknown\n");
 598         else
 599                 seq_printf(seq, "present rate:            %d %s\n",
 600                            battery->current_now, acpi_battery_units(battery));
 601
 602         if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN)
 603                 seq_printf(seq, "remaining capacity:      unknown\n");
 604         else
 605                 seq_printf(seq, "remaining capacity:      %d %sh\n",
 606                            battery->capacity_now, acpi_battery_units(battery));
 607         if (battery->voltage_now == ACPI_BATTERY_VALUE_UNKNOWN)
 608                 seq_printf(seq, "present voltage:         unknown\n");
 609         else
 610                 seq_printf(seq, "present voltage:         %d mV\n",
 611                            battery->voltage_now);
 612       end:
 613         if (result)
 614                 seq_printf(seq, "ERROR: Unable to read battery state\n");
 615
 616         return result;
 617 }
 618
 619 static int acpi_battery_print_alarm(struct seq_file *seq, int result)
 620 {
 621         struct acpi_battery *battery = seq->private;
 622
 623         if (result)
 624                 goto end;
 625
 626         if (!acpi_battery_present(battery)) {
 627                 seq_printf(seq, "present:                 no\n");
 628                 goto end;
 629         }
 630         seq_printf(seq, "alarm:                   ");
 631         if (!battery->alarm)
 632                 seq_printf(seq, "unsupported\n");
 633         else
 634                 seq_printf(seq, "%u %sh\n", battery->alarm,
 635                                 acpi_battery_units(battery));
 636       end:
 637         if (result)
 638                 seq_printf(seq, "ERROR: Unable to read battery alarm\n");
 639         return result;
 640 }
 641
 642 static ssize_t acpi_battery_write_alarm(struct file *file,
 643                                         const char __user * buffer,
 644                                         size_t count, loff_t * ppos)
 645 {
 646         int result = 0;
 647         char alarm_string[12] = { '\0' };
 648         struct seq_file *m = file->private_data;
 649         struct acpi_battery *battery = m->private;
 650
 651         if (!battery || (count > sizeof(alarm_string) - 1))
 652                 return -EINVAL;
 653         if (!acpi_battery_present(battery)) {
 654                 result = -ENODEV;
 655                 goto end;
 656         }
 657         if (copy_from_user(alarm_string, buffer, count)) {
 658                 result = -EFAULT;
 659                 goto end;
 660         }
 661         alarm_string[count] = '\0';
 662         battery->alarm = simple_strtol(alarm_string, NULL, 0);
 663         result = acpi_battery_set_alarm(battery);
 664       end:
 665         if (!result)
 666                 return count;
 667         return result;
 668 }
 669
 670 typedef int(*print_func)(struct seq_file *seq, int result);
 671
 672 static print_func acpi_print_funcs[ACPI_BATTERY_NUMFILES] = {
 673         acpi_battery_print_info,
 674         acpi_battery_print_state,
 675         acpi_battery_print_alarm,
 676 };
 677
 678 static int acpi_battery_read(int fid, struct seq_file *seq)
 679 {
 680         struct acpi_battery *battery = seq->private;
 681         int result = acpi_battery_update(battery);
 682         return acpi_print_funcs[fid](seq, result);
 683 }
 684
 685 #define DECLARE_FILE_FUNCTIONS(_name) \
 686 static int acpi_battery_read_##_name(struct seq_file *seq, void *offset) \
 687 { \
 688         return acpi_battery_read(_name##_tag, seq); \
 689 } \
 690 static int acpi_battery_##_name##_open_fs(struct inode *inode, struct file *file) \
 691 { \
 692         return single_open(file, acpi_battery_read_##_name, PDE(inode)->data); \
 693 }
 694
 695 DECLARE_FILE_FUNCTIONS(info);
 696 DECLARE_FILE_FUNCTIONS(state);
 697 DECLARE_FILE_FUNCTIONS(alarm);
 698
 699 #undef DECLARE_FILE_FUNCTIONS
 700
 701 #define FILE_DESCRIPTION_RO(_name) \
 702         { \
 703         .name = __stringify(_name), \
 704         .mode = S_IRUGO, \
 705         .ops = { \
 706                 .open = acpi_battery_##_name##_open_fs, \
 707                 .read = seq_read, \
 708                 .llseek = seq_lseek, \
 709                 .release = single_release, \
 710                 .owner = THIS_MODULE, \
 711                 }, \
 712         }
 713
 714 #define FILE_DESCRIPTION_RW(_name) \
 715         { \
 716         .name = __stringify(_name), \
 717         .mode = S_IFREG | S_IRUGO | S_IWUSR, \
 718         .ops = { \
 719                 .open = acpi_battery_##_name##_open_fs, \
 720                 .read = seq_read, \
 721                 .llseek = seq_lseek, \
 722                 .write = acpi_battery_write_##_name, \
 723                 .release = single_release, \
 724                 .owner = THIS_MODULE, \
 725                 }, \
 726         }
 727
 728 static struct battery_file {
 729         struct file_operations ops;
 730         mode_t mode;
 731         char *name;
 732 } acpi_battery_file[] = {
 733         FILE_DESCRIPTION_RO(info),
 734         FILE_DESCRIPTION_RO(state),
 735         FILE_DESCRIPTION_RW(alarm),
 736 };
 737
 738 #undef FILE_DESCRIPTION_RO
 739 #undef FILE_DESCRIPTION_RW
 740
 741 static int acpi_battery_add_fs(struct acpi_device *device)
 742 {
 743         struct proc_dir_entry *entry = NULL;
 744         int i;
 745
 746         if (!acpi_device_dir(device)) {
 747                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 748                                                      acpi_battery_dir);
 749                 if (!acpi_device_dir(device))
 750                         return -ENODEV;
 751                 acpi_device_dir(device)->owner = THIS_MODULE;
 752         }
 753
 754         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i) {
 755                 entry = proc_create_data(acpi_battery_file[i].name,
 756                                          acpi_battery_file[i].mode,
 757                                          acpi_device_dir(device),
 758                                          &acpi_battery_file[i].ops,
 759                                          acpi_driver_data(device));
 760                 if (!entry)
 761                         return -ENODEV;
 762         }
 763         return 0;
 764 }
 765
 766 static void acpi_battery_remove_fs(struct acpi_device *device)
 767 {
 768         int i;
 769         if (!acpi_device_dir(device))
 770                 return;
 771         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i)
 772                 remove_proc_entry(acpi_battery_file[i].name,
 773                                   acpi_device_dir(device));
 774
 775         remove_proc_entry(acpi_device_bid(device), acpi_battery_dir);
 776         acpi_device_dir(device) = NULL;
 777 }
 778
 779 #endif
 780
 781 /* --------------------------------------------------------------------------
 782                                  Driver Interface
 783    -------------------------------------------------------------------------- */
 784
 785 static void acpi_battery_notify(acpi_handle handle, u32 event, void *data)
 786 {
 787         struct acpi_battery *battery = data;
 788         struct acpi_device *device;
 789         if (!battery)
 790                 return;
 791         device = battery->device;
 792         acpi_battery_update(battery);
 793         acpi_bus_generate_proc_event(device, event,
 794                                      acpi_battery_present(battery));
 795         acpi_bus_generate_netlink_event(device->pnp.device_class,
 796                                         dev_name(&device->dev), event,
 797                                         acpi_battery_present(battery));
 798 #ifdef CONFIG_ACPI_SYSFS_POWER
 799         /* acpi_batter_update could remove power_supply object */
 800         if (battery->bat.dev)
 801                 kobject_uevent(&battery->bat.dev->kobj, KOBJ_CHANGE);
 802 #endif
 803 }
 804
 805 static int acpi_battery_add(struct acpi_device *device)
 806 {
 807         int result = 0;
 808         acpi_status status = 0;
 809         struct acpi_battery *battery = NULL;
 810         if (!device)
 811                 return -EINVAL;
 812         battery = kzalloc(sizeof(struct acpi_battery), GFP_KERNEL);
 813         if (!battery)
 814                 return -ENOMEM;
 815         battery->device = device;
 816         strcpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
 817         strcpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
 818         device->driver_data = battery;
 819         mutex_init(&battery->lock);
 820         acpi_battery_update(battery);
 821 #ifdef CONFIG_ACPI_PROCFS_POWER
 822         result = acpi_battery_add_fs(device);
 823         if (result)
 824                 goto end;
 825 #endif
 826         status = acpi_install_notify_handler(device->handle,
 827                                              ACPI_ALL_NOTIFY,
 828                                              acpi_battery_notify, battery);
 829         if (ACPI_FAILURE(status)) {
 830                 ACPI_EXCEPTION((AE_INFO, status, "Installing notify handler"));
 831                 result = -ENODEV;
 832                 goto end;
 833         }
 834         printk(KERN_INFO PREFIX "%s Slot [%s] (battery %s)\n",
 835                ACPI_BATTERY_DEVICE_NAME, acpi_device_bid(device),
 836                device->status.battery_present ? "present" : "absent");
 837       end:
 838         if (result) {
 839 #ifdef CONFIG_ACPI_PROCFS_POWER
 840                 acpi_battery_remove_fs(device);
 841 #endif
 842                 kfree(battery);
 843         }
 844         return result;
 845 }
 846
 847 static int acpi_battery_remove(struct acpi_device *device, int type)
 848 {
 849         acpi_status status = 0;
 850         struct acpi_battery *battery = NULL;
 851
 852         if (!device || !acpi_driver_data(device))
 853                 return -EINVAL;
 854         battery = acpi_driver_data(device);
 855         status = acpi_remove_notify_handler(device->handle,
 856                                             ACPI_ALL_NOTIFY,
 857                                             acpi_battery_notify);
 858 #ifdef CONFIG_ACPI_PROCFS_POWER
 859         acpi_battery_remove_fs(device);
 860 #endif
 861 #ifdef CONFIG_ACPI_SYSFS_POWER
 862         sysfs_remove_battery(battery);
 863 #endif
 864         mutex_destroy(&battery->lock);
 865         kfree(battery);
 866         return 0;
 867 }
 868
 869 /* this is needed to learn about changes made in suspended state */
 870 static int acpi_battery_resume(struct acpi_device *device)
 871 {
 872         struct acpi_battery *battery;
 873         if (!device)
 874                 return -EINVAL;
 875         battery = acpi_driver_data(device);
 876         battery->update_time = 0;
 877         acpi_battery_update(battery);
 878         return 0;
 879 }
 880
 881 static struct acpi_driver acpi_battery_driver = {
 882         .name = "battery",
 883         .class = ACPI_BATTERY_CLASS,
 884         .ids = battery_device_ids,
 885         .ops = {
 886                 .add = acpi_battery_add,
 887                 .resume = acpi_battery_resume,
 888                 .remove = acpi_battery_remove,
 889                 },
 890 };
 891
 892 static int __init acpi_battery_init(void)
 893 {
 894         if (acpi_disabled)
 895                 return -ENODEV;
 896 #ifdef CONFIG_ACPI_PROCFS_POWER
 897         acpi_battery_dir = acpi_lock_battery_dir();
 898         if (!acpi_battery_dir)
 899                 return -ENODEV;
 900 #endif
 901         if (acpi_bus_register_driver(&acpi_battery_driver) < 0) {
 902 #ifdef CONFIG_ACPI_PROCFS_POWER
 903                 acpi_unlock_battery_dir(acpi_battery_dir);
 904 #endif
 905                 return -ENODEV;
 906         }
 907         return 0;
 908 }
 909
 910 static void __exit acpi_battery_exit(void)
 911 {
 912         acpi_bus_unregister_driver(&acpi_battery_driver);
 913 #ifdef CONFIG_ACPI_PROCFS_POWER
 914         acpi_unlock_battery_dir(acpi_battery_dir);
 915 #endif
 916 }
 917
 918 module_init(acpi_battery_init);
 919 module_exit(acpi_battery_exit);