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   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_COMPONENT          0x00040000
  50 #define ACPI_BATTERY_CLASS              "battery"
  51 #define ACPI_BATTERY_DEVICE_NAME        "Battery"
  52 #define ACPI_BATTERY_NOTIFY_STATUS      0x80
  53 #define ACPI_BATTERY_NOTIFY_INFO        0x81
  54
  55 #define _COMPONENT              ACPI_BATTERY_COMPONENT
  56
  57 ACPI_MODULE_NAME("battery");
  58
  59 MODULE_AUTHOR("Paul Diefenbaugh");
  60 MODULE_AUTHOR("Alexey Starikovskiy <astarikovskiy@suse.de>");
  61 MODULE_DESCRIPTION("ACPI Battery Driver");
  62 MODULE_LICENSE("GPL");
  63
  64 static unsigned int cache_time = 1000;
  65 module_param(cache_time, uint, 0644);
  66 MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
  67
  68 #ifdef CONFIG_ACPI_PROCFS_POWER
  69 extern struct proc_dir_entry *acpi_lock_battery_dir(void);
  70 extern void *acpi_unlock_battery_dir(struct proc_dir_entry *acpi_battery_dir);
  71
  72 enum acpi_battery_files {
  73         info_tag = 0,
  74         state_tag,
  75         alarm_tag,
  76         ACPI_BATTERY_NUMFILES,
  77 };
  78
  79 #endif
  80
  81 static const struct acpi_device_id battery_device_ids[] = {
  82         {"PNP0C0A", 0},
  83         {"", 0},
  84 };
  85
  86 MODULE_DEVICE_TABLE(acpi, battery_device_ids);
  87
  88
  89 struct acpi_battery {
  90         struct mutex lock;
  91 #ifdef CONFIG_ACPI_SYSFS_POWER
  92         struct power_supply bat;
  93 #endif
  94         struct acpi_device *device;
  95         unsigned long update_time;
  96         int current_now;
  97         int capacity_now;
  98         int voltage_now;
  99         int design_capacity;
 100         int full_charge_capacity;
 101         int technology;
 102         int design_voltage;
 103         int design_capacity_warning;
 104         int design_capacity_low;
 105         int capacity_granularity_1;
 106         int capacity_granularity_2;
 107         int alarm;
 108         char model_number[32];
 109         char serial_number[32];
 110         char type[32];
 111         char oem_info[32];
 112         int state;
 113         int power_unit;
 114         u8 alarm_present;
 115 };
 116
 117 #define to_acpi_battery(x) container_of(x, struct acpi_battery, bat);
 118
 119 inline int acpi_battery_present(struct acpi_battery *battery)
 120 {
 121         return battery->device->status.battery_present;
 122 }
 123
 124 #ifdef CONFIG_ACPI_SYSFS_POWER
 125 static int acpi_battery_technology(struct acpi_battery *battery)
 126 {
 127         if (!strcasecmp("NiCd", battery->type))
 128                 return POWER_SUPPLY_TECHNOLOGY_NiCd;
 129         if (!strcasecmp("NiMH", battery->type))
 130                 return POWER_SUPPLY_TECHNOLOGY_NiMH;
 131         if (!strcasecmp("LION", battery->type))
 132                 return POWER_SUPPLY_TECHNOLOGY_LION;
 133         if (!strncasecmp("LI-ION", battery->type, 6))
 134                 return POWER_SUPPLY_TECHNOLOGY_LION;
 135         if (!strcasecmp("LiP", battery->type))
 136                 return POWER_SUPPLY_TECHNOLOGY_LIPO;
 137         return POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
 138 }
 139
 140 static int acpi_battery_get_state(struct acpi_battery *battery);
 141
 142 static int acpi_battery_get_property(struct power_supply *psy,
 143                                      enum power_supply_property psp,
 144                                      union power_supply_propval *val)
 145 {
 146         struct acpi_battery *battery = to_acpi_battery(psy);
 147
 148         if (acpi_battery_present(battery)) {
 149                 /* run battery update only if it is present */
 150                 acpi_battery_get_state(battery);
 151         } else if (psp != POWER_SUPPLY_PROP_PRESENT)
 152                 return -ENODEV;
 153         switch (psp) {
 154         case POWER_SUPPLY_PROP_STATUS:
 155                 if (battery->state & 0x01)
 156                         val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
 157                 else if (battery->state & 0x02)
 158                         val->intval = POWER_SUPPLY_STATUS_CHARGING;
 159                 else if (battery->state == 0)
 160                         val->intval = POWER_SUPPLY_STATUS_FULL;
 161                 else
 162                         val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
 163                 break;
 164         case POWER_SUPPLY_PROP_PRESENT:
 165                 val->intval = acpi_battery_present(battery);
 166                 break;
 167         case POWER_SUPPLY_PROP_TECHNOLOGY:
 168                 val->intval = acpi_battery_technology(battery);
 169                 break;
 170         case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
 171                 val->intval = battery->design_voltage * 1000;
 172                 break;
 173         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 174                 val->intval = battery->voltage_now * 1000;
 175                 break;
 176         case POWER_SUPPLY_PROP_CURRENT_NOW:
 177                 val->intval = battery->current_now * 1000;
 178                 break;
 179         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
 180         case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
 181                 val->intval = battery->design_capacity * 1000;
 182                 break;
 183         case POWER_SUPPLY_PROP_CHARGE_FULL:
 184         case POWER_SUPPLY_PROP_ENERGY_FULL:
 185                 val->intval = battery->full_charge_capacity * 1000;
 186                 break;
 187         case POWER_SUPPLY_PROP_CHARGE_NOW:
 188         case POWER_SUPPLY_PROP_ENERGY_NOW:
 189                 val->intval = battery->capacity_now * 1000;
 190                 break;
 191         case POWER_SUPPLY_PROP_MODEL_NAME:
 192                 val->strval = battery->model_number;
 193                 break;
 194         case POWER_SUPPLY_PROP_MANUFACTURER:
 195                 val->strval = battery->oem_info;
 196                 break;
 197         case POWER_SUPPLY_PROP_SERIAL_NUMBER:
 198                 val->strval = battery->serial_number;
 199                 break;
 200         default:
 201                 return -EINVAL;
 202         }
 203         return 0;
 204 }
 205
 206 static enum power_supply_property charge_battery_props[] = {
 207         POWER_SUPPLY_PROP_STATUS,
 208         POWER_SUPPLY_PROP_PRESENT,
 209         POWER_SUPPLY_PROP_TECHNOLOGY,
 210         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 211         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 212         POWER_SUPPLY_PROP_CURRENT_NOW,
 213         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 214         POWER_SUPPLY_PROP_CHARGE_FULL,
 215         POWER_SUPPLY_PROP_CHARGE_NOW,
 216         POWER_SUPPLY_PROP_MODEL_NAME,
 217         POWER_SUPPLY_PROP_MANUFACTURER,
 218         POWER_SUPPLY_PROP_SERIAL_NUMBER,
 219 };
 220
 221 static enum power_supply_property energy_battery_props[] = {
 222         POWER_SUPPLY_PROP_STATUS,
 223         POWER_SUPPLY_PROP_PRESENT,
 224         POWER_SUPPLY_PROP_TECHNOLOGY,
 225         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 226         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 227         POWER_SUPPLY_PROP_CURRENT_NOW,
 228         POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
 229         POWER_SUPPLY_PROP_ENERGY_FULL,
 230         POWER_SUPPLY_PROP_ENERGY_NOW,
 231         POWER_SUPPLY_PROP_MODEL_NAME,
 232         POWER_SUPPLY_PROP_MANUFACTURER,
 233         POWER_SUPPLY_PROP_SERIAL_NUMBER,
 234 };
 235 #endif
 236
 237 #ifdef CONFIG_ACPI_PROCFS_POWER
 238 inline char *acpi_battery_units(struct acpi_battery *battery)
 239 {
 240         return (battery->power_unit)?"mA":"mW";
 241 }
 242 #endif
 243
 244 /* --------------------------------------------------------------------------
 245                                Battery Management
 246    -------------------------------------------------------------------------- */
 247 struct acpi_offsets {
 248         size_t offset;          /* offset inside struct acpi_sbs_battery */
 249         u8 mode;                /* int or string? */
 250 };
 251
 252 static struct acpi_offsets state_offsets[] = {
 253         {offsetof(struct acpi_battery, state), 0},
 254         {offsetof(struct acpi_battery, current_now), 0},
 255         {offsetof(struct acpi_battery, capacity_now), 0},
 256         {offsetof(struct acpi_battery, voltage_now), 0},
 257 };
 258
 259 static struct acpi_offsets info_offsets[] = {
 260         {offsetof(struct acpi_battery, power_unit), 0},
 261         {offsetof(struct acpi_battery, design_capacity), 0},
 262         {offsetof(struct acpi_battery, full_charge_capacity), 0},
 263         {offsetof(struct acpi_battery, technology), 0},
 264         {offsetof(struct acpi_battery, design_voltage), 0},
 265         {offsetof(struct acpi_battery, design_capacity_warning), 0},
 266         {offsetof(struct acpi_battery, design_capacity_low), 0},
 267         {offsetof(struct acpi_battery, capacity_granularity_1), 0},
 268         {offsetof(struct acpi_battery, capacity_granularity_2), 0},
 269         {offsetof(struct acpi_battery, model_number), 1},
 270         {offsetof(struct acpi_battery, serial_number), 1},
 271         {offsetof(struct acpi_battery, type), 1},
 272         {offsetof(struct acpi_battery, oem_info), 1},
 273 };
 274
 275 static int extract_package(struct acpi_battery *battery,
 276                            union acpi_object *package,
 277                            struct acpi_offsets *offsets, int num)
 278 {
 279         int i;
 280         union acpi_object *element;
 281         if (package->type != ACPI_TYPE_PACKAGE)
 282                 return -EFAULT;
 283         for (i = 0; i < num; ++i) {
 284                 if (package->package.count <= i)
 285                         return -EFAULT;
 286                 element = &package->package.elements[i];
 287                 if (offsets[i].mode) {
 288                         u8 *ptr = (u8 *)battery + offsets[i].offset;
 289                         if (element->type == ACPI_TYPE_STRING ||
 290                             element->type == ACPI_TYPE_BUFFER)
 291                                 strncpy(ptr, element->string.pointer, 32);
 292                         else if (element->type == ACPI_TYPE_INTEGER) {
 293                                 strncpy(ptr, (u8 *)&element->integer.value,
 294                                         sizeof(acpi_integer));
 295                                 ptr[sizeof(acpi_integer)] = 0;
 296                         } else
 297                                 *ptr = 0; /* don't have value */
 298                 } else {
 299                         int *x = (int *)((u8 *)battery + offsets[i].offset);
 300                         *x = (element->type == ACPI_TYPE_INTEGER) ?
 301                                 element->integer.value : -1;
 302                 }
 303         }
 304         return 0;
 305 }
 306
 307 static int acpi_battery_get_status(struct acpi_battery *battery)
 308 {
 309         if (acpi_bus_get_status(battery->device)) {
 310                 ACPI_EXCEPTION((AE_INFO, AE_ERROR, "Evaluating _STA"));
 311                 return -ENODEV;
 312         }
 313         return 0;
 314 }
 315
 316 static int acpi_battery_get_info(struct acpi_battery *battery)
 317 {
 318         int result = -EFAULT;
 319         acpi_status status = 0;
 320         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 321
 322         if (!acpi_battery_present(battery))
 323                 return 0;
 324         mutex_lock(&battery->lock);
 325         status = acpi_evaluate_object(battery->device->handle, "_BIF",
 326                                       NULL, &buffer);
 327         mutex_unlock(&battery->lock);
 328
 329         if (ACPI_FAILURE(status)) {
 330                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BIF"));
 331                 return -ENODEV;
 332         }
 333
 334         result = extract_package(battery, buffer.pointer,
 335                                  info_offsets, ARRAY_SIZE(info_offsets));
 336         kfree(buffer.pointer);
 337         return result;
 338 }
 339
 340 static int acpi_battery_get_state(struct acpi_battery *battery)
 341 {
 342         int result = 0;
 343         acpi_status status = 0;
 344         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 345
 346         if (!acpi_battery_present(battery))
 347                 return 0;
 348
 349         if (battery->update_time &&
 350             time_before(jiffies, battery->update_time +
 351                         msecs_to_jiffies(cache_time)))
 352                 return 0;
 353
 354         mutex_lock(&battery->lock);
 355         status = acpi_evaluate_object(battery->device->handle, "_BST",
 356                                       NULL, &buffer);
 357         mutex_unlock(&battery->lock);
 358
 359         if (ACPI_FAILURE(status)) {
 360                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BST"));
 361                 return -ENODEV;
 362         }
 363
 364         result = extract_package(battery, buffer.pointer,
 365                                  state_offsets, ARRAY_SIZE(state_offsets));
 366         battery->update_time = jiffies;
 367         kfree(buffer.pointer);
 368         return result;
 369 }
 370
 371 static int acpi_battery_set_alarm(struct acpi_battery *battery)
 372 {
 373         acpi_status status = 0;
 374         union acpi_object arg0 = { .type = ACPI_TYPE_INTEGER };
 375         struct acpi_object_list arg_list = { 1, &arg0 };
 376
 377         if (!acpi_battery_present(battery)|| !battery->alarm_present)
 378                 return -ENODEV;
 379
 380         arg0.integer.value = battery->alarm;
 381
 382         mutex_lock(&battery->lock);
 383         status = acpi_evaluate_object(battery->device->handle, "_BTP",
 384                                  &arg_list, NULL);
 385         mutex_unlock(&battery->lock);
 386
 387         if (ACPI_FAILURE(status))
 388                 return -ENODEV;
 389
 390         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Alarm set to %d\n", battery->alarm));
 391         return 0;
 392 }
 393
 394 static int acpi_battery_init_alarm(struct acpi_battery *battery)
 395 {
 396         acpi_status status = AE_OK;
 397         acpi_handle handle = NULL;
 398
 399         /* See if alarms are supported, and if so, set default */
 400         status = acpi_get_handle(battery->device->handle, "_BTP", &handle);
 401         if (ACPI_FAILURE(status)) {
 402                 battery->alarm_present = 0;
 403                 return 0;
 404         }
 405         battery->alarm_present = 1;
 406         if (!battery->alarm)
 407                 battery->alarm = battery->design_capacity_warning;
 408         return acpi_battery_set_alarm(battery);
 409 }
 410
 411 #ifdef CONFIG_ACPI_SYSFS_POWER
 412 static ssize_t acpi_battery_alarm_show(struct device *dev,
 413                                         struct device_attribute *attr,
 414                                         char *buf)
 415 {
 416         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
 417         return sprintf(buf, "%d\n", battery->alarm * 1000);
 418 }
 419
 420 static ssize_t acpi_battery_alarm_store(struct device *dev,
 421                                         struct device_attribute *attr,
 422                                         const char *buf, size_t count)
 423 {
 424         unsigned long x;
 425         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
 426         if (sscanf(buf, "%ld\n", &x) == 1)
 427                 battery->alarm = x/1000;
 428         if (acpi_battery_present(battery))
 429                 acpi_battery_set_alarm(battery);
 430         return count;
 431 }
 432
 433 static struct device_attribute alarm_attr = {
 434         .attr = {.name = "alarm", .mode = 0644, .owner = THIS_MODULE},
 435         .show = acpi_battery_alarm_show,
 436         .store = acpi_battery_alarm_store,
 437 };
 438
 439 static int sysfs_add_battery(struct acpi_battery *battery)
 440 {
 441         int result;
 442
 443         if (battery->power_unit) {
 444                 battery->bat.properties = charge_battery_props;
 445                 battery->bat.num_properties =
 446                         ARRAY_SIZE(charge_battery_props);
 447         } else {
 448                 battery->bat.properties = energy_battery_props;
 449                 battery->bat.num_properties =
 450                         ARRAY_SIZE(energy_battery_props);
 451         }
 452
 453         battery->bat.name = acpi_device_bid(battery->device);
 454         battery->bat.type = POWER_SUPPLY_TYPE_BATTERY;
 455         battery->bat.get_property = acpi_battery_get_property;
 456
 457         result = power_supply_register(&battery->device->dev, &battery->bat);
 458         if (result)
 459                 return result;
 460         return device_create_file(battery->bat.dev, &alarm_attr);
 461 }
 462
 463 static void sysfs_remove_battery(struct acpi_battery *battery)
 464 {
 465         if (!battery->bat.dev)
 466                 return;
 467         device_remove_file(battery->bat.dev, &alarm_attr);
 468         power_supply_unregister(&battery->bat);
 469         battery->bat.dev = NULL;
 470 }
 471 #endif
 472
 473 static int acpi_battery_update(struct acpi_battery *battery)
 474 {
 475         int result;
 476         result = acpi_battery_get_status(battery);
 477         if (result)
 478                 return result;
 479 #ifdef CONFIG_ACPI_SYSFS_POWER
 480         if (!acpi_battery_present(battery)) {
 481                 sysfs_remove_battery(battery);
 482                 battery->update_time = 0;
 483                 return 0;
 484         }
 485 #endif
 486         if (!battery->update_time) {
 487                 result = acpi_battery_get_info(battery);
 488                 if (result)
 489                         return result;
 490                 acpi_battery_init_alarm(battery);
 491         }
 492 #ifdef CONFIG_ACPI_SYSFS_POWER
 493         if (!battery->bat.dev)
 494                 sysfs_add_battery(battery);
 495 #endif
 496         return acpi_battery_get_state(battery);
 497 }
 498
 499 /* --------------------------------------------------------------------------
 500                               FS Interface (/proc)
 501    -------------------------------------------------------------------------- */
 502
 503 #ifdef CONFIG_ACPI_PROCFS_POWER
 504 static struct proc_dir_entry *acpi_battery_dir;
 505
 506 static int acpi_battery_print_info(struct seq_file *seq, int result)
 507 {
 508         struct acpi_battery *battery = seq->private;
 509
 510         if (result)
 511                 goto end;
 512
 513         seq_printf(seq, "present:                 %s\n",
 514                    acpi_battery_present(battery)?"yes":"no");
 515         if (!acpi_battery_present(battery))
 516                 goto end;
 517         if (battery->design_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
 518                 seq_printf(seq, "design capacity:         unknown\n");
 519         else
 520                 seq_printf(seq, "design capacity:         %d %sh\n",
 521                            battery->design_capacity,
 522                            acpi_battery_units(battery));
 523
 524         if (battery->full_charge_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
 525                 seq_printf(seq, "last full capacity:      unknown\n");
 526         else
 527                 seq_printf(seq, "last full capacity:      %d %sh\n",
 528                            battery->full_charge_capacity,
 529                            acpi_battery_units(battery));
 530
 531         seq_printf(seq, "battery technology:      %srechargeable\n",
 532                    (!battery->technology)?"non-":"");
 533
 534         if (battery->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
 535                 seq_printf(seq, "design voltage:          unknown\n");
 536         else
 537                 seq_printf(seq, "design voltage:          %d mV\n",
 538                            battery->design_voltage);
 539         seq_printf(seq, "design capacity warning: %d %sh\n",
 540                    battery->design_capacity_warning,
 541                    acpi_battery_units(battery));
 542         seq_printf(seq, "design capacity low:     %d %sh\n",
 543                    battery->design_capacity_low,
 544                    acpi_battery_units(battery));
 545         seq_printf(seq, "capacity granularity 1:  %d %sh\n",
 546                    battery->capacity_granularity_1,
 547                    acpi_battery_units(battery));
 548         seq_printf(seq, "capacity granularity 2:  %d %sh\n",
 549                    battery->capacity_granularity_2,
 550                    acpi_battery_units(battery));
 551         seq_printf(seq, "model number:            %s\n", battery->model_number);
 552         seq_printf(seq, "serial number:           %s\n", battery->serial_number);
 553         seq_printf(seq, "battery type:            %s\n", battery->type);
 554         seq_printf(seq, "OEM info:                %s\n", battery->oem_info);
 555       end:
 556         if (result)
 557                 seq_printf(seq, "ERROR: Unable to read battery info\n");
 558         return result;
 559 }
 560
 561 static int acpi_battery_print_state(struct seq_file *seq, int result)
 562 {
 563         struct acpi_battery *battery = seq->private;
 564
 565         if (result)
 566                 goto end;
 567
 568         seq_printf(seq, "present:                 %s\n",
 569                    acpi_battery_present(battery)?"yes":"no");
 570         if (!acpi_battery_present(battery))
 571                 goto end;
 572
 573         seq_printf(seq, "capacity state:          %s\n",
 574                         (battery->state & 0x04)?"critical":"ok");
 575         if ((battery->state & 0x01) && (battery->state & 0x02))
 576                 seq_printf(seq,
 577                            "charging state:          charging/discharging\n");
 578         else if (battery->state & 0x01)
 579                 seq_printf(seq, "charging state:          discharging\n");
 580         else if (battery->state & 0x02)
 581                 seq_printf(seq, "charging state:          charging\n");
 582         else
 583                 seq_printf(seq, "charging state:          charged\n");
 584
 585         if (battery->current_now == ACPI_BATTERY_VALUE_UNKNOWN)
 586                 seq_printf(seq, "present rate:            unknown\n");
 587         else
 588                 seq_printf(seq, "present rate:            %d %s\n",
 589                            battery->current_now, acpi_battery_units(battery));
 590
 591         if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN)
 592                 seq_printf(seq, "remaining capacity:      unknown\n");
 593         else
 594                 seq_printf(seq, "remaining capacity:      %d %sh\n",
 595                            battery->capacity_now, acpi_battery_units(battery));
 596         if (battery->voltage_now == ACPI_BATTERY_VALUE_UNKNOWN)
 597                 seq_printf(seq, "present voltage:         unknown\n");
 598         else
 599                 seq_printf(seq, "present voltage:         %d mV\n",
 600                            battery->voltage_now);
 601       end:
 602         if (result)
 603                 seq_printf(seq, "ERROR: Unable to read battery state\n");
 604
 605         return result;
 606 }
 607
 608 static int acpi_battery_print_alarm(struct seq_file *seq, int result)
 609 {
 610         struct acpi_battery *battery = seq->private;
 611
 612         if (result)
 613                 goto end;
 614
 615         if (!acpi_battery_present(battery)) {
 616                 seq_printf(seq, "present:                 no\n");
 617                 goto end;
 618         }
 619         seq_printf(seq, "alarm:                   ");
 620         if (!battery->alarm)
 621                 seq_printf(seq, "unsupported\n");
 622         else
 623                 seq_printf(seq, "%u %sh\n", battery->alarm,
 624                                 acpi_battery_units(battery));
 625       end:
 626         if (result)
 627                 seq_printf(seq, "ERROR: Unable to read battery alarm\n");
 628         return result;
 629 }
 630
 631 static ssize_t acpi_battery_write_alarm(struct file *file,
 632                                         const char __user * buffer,
 633                                         size_t count, loff_t * ppos)
 634 {
 635         int result = 0;
 636         char alarm_string[12] = { '\0' };
 637         struct seq_file *m = file->private_data;
 638         struct acpi_battery *battery = m->private;
 639
 640         if (!battery || (count > sizeof(alarm_string) - 1))
 641                 return -EINVAL;
 642         if (!acpi_battery_present(battery)) {
 643                 result = -ENODEV;
 644                 goto end;
 645         }
 646         if (copy_from_user(alarm_string, buffer, count)) {
 647                 result = -EFAULT;
 648                 goto end;
 649         }
 650         alarm_string[count] = '\0';
 651         battery->alarm = simple_strtol(alarm_string, NULL, 0);
 652         result = acpi_battery_set_alarm(battery);
 653       end:
 654         if (!result)
 655                 return count;
 656         return result;
 657 }
 658
 659 typedef int(*print_func)(struct seq_file *seq, int result);
 660
 661 static print_func acpi_print_funcs[ACPI_BATTERY_NUMFILES] = {
 662         acpi_battery_print_info,
 663         acpi_battery_print_state,
 664         acpi_battery_print_alarm,
 665 };
 666
 667 static int acpi_battery_read(int fid, struct seq_file *seq)
 668 {
 669         struct acpi_battery *battery = seq->private;
 670         int result = acpi_battery_update(battery);
 671         return acpi_print_funcs[fid](seq, result);
 672 }
 673
 674 #define DECLARE_FILE_FUNCTIONS(_name) \
 675 static int acpi_battery_read_##_name(struct seq_file *seq, void *offset) \
 676 { \
 677         return acpi_battery_read(_name##_tag, seq); \
 678 } \
 679 static int acpi_battery_##_name##_open_fs(struct inode *inode, struct file *file) \
 680 { \
 681         return single_open(file, acpi_battery_read_##_name, PDE(inode)->data); \
 682 }
 683
 684 DECLARE_FILE_FUNCTIONS(info);
 685 DECLARE_FILE_FUNCTIONS(state);
 686 DECLARE_FILE_FUNCTIONS(alarm);
 687
 688 #undef DECLARE_FILE_FUNCTIONS
 689
 690 #define FILE_DESCRIPTION_RO(_name) \
 691         { \
 692         .name = __stringify(_name), \
 693         .mode = S_IRUGO, \
 694         .ops = { \
 695                 .open = acpi_battery_##_name##_open_fs, \
 696                 .read = seq_read, \
 697                 .llseek = seq_lseek, \
 698                 .release = single_release, \
 699                 .owner = THIS_MODULE, \
 700                 }, \
 701         }
 702
 703 #define FILE_DESCRIPTION_RW(_name) \
 704         { \
 705         .name = __stringify(_name), \
 706         .mode = S_IFREG | S_IRUGO | S_IWUSR, \
 707         .ops = { \
 708                 .open = acpi_battery_##_name##_open_fs, \
 709                 .read = seq_read, \
 710                 .llseek = seq_lseek, \
 711                 .write = acpi_battery_write_##_name, \
 712                 .release = single_release, \
 713                 .owner = THIS_MODULE, \
 714                 }, \
 715         }
 716
 717 static struct battery_file {
 718         struct file_operations ops;
 719         mode_t mode;
 720         char *name;
 721 } acpi_battery_file[] = {
 722         FILE_DESCRIPTION_RO(info),
 723         FILE_DESCRIPTION_RO(state),
 724         FILE_DESCRIPTION_RW(alarm),
 725 };
 726
 727 #undef FILE_DESCRIPTION_RO
 728 #undef FILE_DESCRIPTION_RW
 729
 730 static int acpi_battery_add_fs(struct acpi_device *device)
 731 {
 732         struct proc_dir_entry *entry = NULL;
 733         int i;
 734
 735         if (!acpi_device_dir(device)) {
 736                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 737                                                      acpi_battery_dir);
 738                 if (!acpi_device_dir(device))
 739                         return -ENODEV;
 740                 acpi_device_dir(device)->owner = THIS_MODULE;
 741         }
 742
 743         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i) {
 744                 entry = proc_create_data(acpi_battery_file[i].name,
 745                                          acpi_battery_file[i].mode,
 746                                          acpi_device_dir(device),
 747                                          &acpi_battery_file[i].ops,
 748                                          acpi_driver_data(device));
 749                 if (!entry)
 750                         return -ENODEV;
 751         }
 752         return 0;
 753 }
 754
 755 static void acpi_battery_remove_fs(struct acpi_device *device)
 756 {
 757         int i;
 758         if (!acpi_device_dir(device))
 759                 return;
 760         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i)
 761                 remove_proc_entry(acpi_battery_file[i].name,
 762                                   acpi_device_dir(device));
 763
 764         remove_proc_entry(acpi_device_bid(device), acpi_battery_dir);
 765         acpi_device_dir(device) = NULL;
 766 }
 767
 768 #endif
 769
 770 /* --------------------------------------------------------------------------
 771                                  Driver Interface
 772    -------------------------------------------------------------------------- */
 773
 774 static void acpi_battery_notify(acpi_handle handle, u32 event, void *data)
 775 {
 776         struct acpi_battery *battery = data;
 777         struct acpi_device *device;
 778         if (!battery)
 779                 return;
 780         device = battery->device;
 781         acpi_battery_update(battery);
 782         acpi_bus_generate_proc_event(device, event,
 783                                      acpi_battery_present(battery));
 784         acpi_bus_generate_netlink_event(device->pnp.device_class,
 785                                         device->dev.bus_id, event,
 786                                         acpi_battery_present(battery));
 787 #ifdef CONFIG_ACPI_SYSFS_POWER
 788         /* acpi_batter_update could remove power_supply object */
 789         if (battery->bat.dev)
 790                 kobject_uevent(&battery->bat.dev->kobj, KOBJ_CHANGE);
 791 #endif
 792 }
 793
 794 static int acpi_battery_add(struct acpi_device *device)
 795 {
 796         int result = 0;
 797         acpi_status status = 0;
 798         struct acpi_battery *battery = NULL;
 799         if (!device)
 800                 return -EINVAL;
 801         battery = kzalloc(sizeof(struct acpi_battery), GFP_KERNEL);
 802         if (!battery)
 803                 return -ENOMEM;
 804         battery->device = device;
 805         strcpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
 806         strcpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
 807         acpi_driver_data(device) = battery;
 808         mutex_init(&battery->lock);
 809         acpi_battery_update(battery);
 810 #ifdef CONFIG_ACPI_PROCFS_POWER
 811         result = acpi_battery_add_fs(device);
 812         if (result)
 813                 goto end;
 814 #endif
 815         status = acpi_install_notify_handler(device->handle,
 816                                              ACPI_ALL_NOTIFY,
 817                                              acpi_battery_notify, battery);
 818         if (ACPI_FAILURE(status)) {
 819                 ACPI_EXCEPTION((AE_INFO, status, "Installing notify handler"));
 820                 result = -ENODEV;
 821                 goto end;
 822         }
 823         printk(KERN_INFO PREFIX "%s Slot [%s] (battery %s)\n",
 824                ACPI_BATTERY_DEVICE_NAME, acpi_device_bid(device),
 825                device->status.battery_present ? "present" : "absent");
 826       end:
 827         if (result) {
 828 #ifdef CONFIG_ACPI_PROCFS_POWER
 829                 acpi_battery_remove_fs(device);
 830 #endif
 831                 kfree(battery);
 832         }
 833         return result;
 834 }
 835
 836 static int acpi_battery_remove(struct acpi_device *device, int type)
 837 {
 838         acpi_status status = 0;
 839         struct acpi_battery *battery = NULL;
 840
 841         if (!device || !acpi_driver_data(device))
 842                 return -EINVAL;
 843         battery = acpi_driver_data(device);
 844         status = acpi_remove_notify_handler(device->handle,
 845                                             ACPI_ALL_NOTIFY,
 846                                             acpi_battery_notify);
 847 #ifdef CONFIG_ACPI_PROCFS_POWER
 848         acpi_battery_remove_fs(device);
 849 #endif
 850 #ifdef CONFIG_ACPI_SYSFS_POWER
 851         sysfs_remove_battery(battery);
 852 #endif
 853         mutex_destroy(&battery->lock);
 854         kfree(battery);
 855         return 0;
 856 }
 857
 858 /* this is needed to learn about changes made in suspended state */
 859 static int acpi_battery_resume(struct acpi_device *device)
 860 {
 861         struct acpi_battery *battery;
 862         if (!device)
 863                 return -EINVAL;
 864         battery = acpi_driver_data(device);
 865         battery->update_time = 0;
 866         acpi_battery_update(battery);
 867         return 0;
 868 }
 869
 870 static struct acpi_driver acpi_battery_driver = {
 871         .name = "battery",
 872         .class = ACPI_BATTERY_CLASS,
 873         .ids = battery_device_ids,
 874         .ops = {
 875                 .add = acpi_battery_add,
 876                 .resume = acpi_battery_resume,
 877                 .remove = acpi_battery_remove,
 878                 },
 879 };
 880
 881 static int __init acpi_battery_init(void)
 882 {
 883         if (acpi_disabled)
 884                 return -ENODEV;
 885 #ifdef CONFIG_ACPI_PROCFS_POWER
 886         acpi_battery_dir = acpi_lock_battery_dir();
 887         if (!acpi_battery_dir)
 888                 return -ENODEV;
 889 #endif
 890         if (acpi_bus_register_driver(&acpi_battery_driver) < 0) {
 891 #ifdef CONFIG_ACPI_PROCFS_POWER
 892                 acpi_unlock_battery_dir(acpi_battery_dir);
 893 #endif
 894                 return -ENODEV;
 895         }
 896         return 0;
 897 }
 898
 899 static void __exit acpi_battery_exit(void)
 900 {
 901         acpi_bus_unregister_driver(&acpi_battery_driver);
 902 #ifdef CONFIG_ACPI_PROCFS_POWER
 903         acpi_unlock_battery_dir(acpi_battery_dir);
 904 #endif
 905 }
 906
 907 module_init(acpi_battery_init);
 908 module_exit(acpi_battery_exit);