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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
  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 #include <linux/power_supply.h>
  44
  45 #define ACPI_BATTERY_VALUE_UNKNOWN 0xFFFFFFFF
  46
  47 #define ACPI_BATTERY_COMPONENT          0x00040000
  48 #define ACPI_BATTERY_CLASS              "battery"
  49 #define ACPI_BATTERY_DEVICE_NAME        "Battery"
  50 #define ACPI_BATTERY_NOTIFY_STATUS      0x80
  51 #define ACPI_BATTERY_NOTIFY_INFO        0x81
  52
  53 #define _COMPONENT              ACPI_BATTERY_COMPONENT
  54
  55 ACPI_MODULE_NAME("battery");
  56
  57 MODULE_AUTHOR("Paul Diefenbaugh");
  58 MODULE_AUTHOR("Alexey Starikovskiy <astarikovskiy@suse.de>");
  59 MODULE_DESCRIPTION("ACPI Battery Driver");
  60 MODULE_LICENSE("GPL");
  61
  62 static unsigned int cache_time = 1000;
  63 module_param(cache_time, uint, 0644);
  64 MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
  65
  66 #ifdef CONFIG_ACPI_PROCFS
  67 extern struct proc_dir_entry *acpi_lock_battery_dir(void);
  68 extern void *acpi_unlock_battery_dir(struct proc_dir_entry *acpi_battery_dir);
  69
  70 enum acpi_battery_files {
  71         info_tag = 0,
  72         state_tag,
  73         alarm_tag,
  74         ACPI_BATTERY_NUMFILES,
  75 };
  76
  77 #endif
  78
  79 static const struct acpi_device_id battery_device_ids[] = {
  80         {"PNP0C0A", 0},
  81         {"", 0},
  82 };
  83
  84 MODULE_DEVICE_TABLE(acpi, battery_device_ids);
  85
  86
  87 struct acpi_battery {
  88         struct mutex lock;
  89         struct power_supply bat;
  90         struct acpi_device *device;
  91         unsigned long update_time;
  92         int current_now;
  93         int capacity_now;
  94         int voltage_now;
  95         int design_capacity;
  96         int full_charge_capacity;
  97         int technology;
  98         int design_voltage;
  99         int design_capacity_warning;
 100         int design_capacity_low;
 101         int capacity_granularity_1;
 102         int capacity_granularity_2;
 103         int alarm;
 104         char model_number[32];
 105         char serial_number[32];
 106         char type[32];
 107         char oem_info[32];
 108         int state;
 109         int power_unit;
 110         u8 alarm_present;
 111 };
 112
 113 #define to_acpi_battery(x) container_of(x, struct acpi_battery, bat);
 114
 115 inline int acpi_battery_present(struct acpi_battery *battery)
 116 {
 117         return battery->device->status.battery_present;
 118 }
 119
 120 static int acpi_battery_technology(struct acpi_battery *battery)
 121 {
 122         if (!strcasecmp("NiCd", battery->type))
 123                 return POWER_SUPPLY_TECHNOLOGY_NiCd;
 124         if (!strcasecmp("NiMH", battery->type))
 125                 return POWER_SUPPLY_TECHNOLOGY_NiMH;
 126         if (!strcasecmp("LION", battery->type))
 127                 return POWER_SUPPLY_TECHNOLOGY_LION;
 128         if (!strcasecmp("LI-ION", battery->type))
 129                 return POWER_SUPPLY_TECHNOLOGY_LION;
 130         if (!strcasecmp("LiP", battery->type))
 131                 return POWER_SUPPLY_TECHNOLOGY_LIPO;
 132         return POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
 133 }
 134
 135 static int acpi_battery_update(struct acpi_battery *battery);
 136
 137 static int acpi_battery_get_property(struct power_supply *psy,
 138                                      enum power_supply_property psp,
 139                                      union power_supply_propval *val)
 140 {
 141         struct acpi_battery *battery = to_acpi_battery(psy);
 142
 143         if ((!acpi_battery_present(battery)) &&
 144              psp != POWER_SUPPLY_PROP_PRESENT)
 145                 return -ENODEV;
 146         acpi_battery_update(battery);
 147         switch (psp) {
 148         case POWER_SUPPLY_PROP_STATUS:
 149                 if (battery->state & 0x01)
 150                         val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
 151                 else if (battery->state & 0x02)
 152                         val->intval = POWER_SUPPLY_STATUS_CHARGING;
 153                 else if (battery->state == 0)
 154                         val->intval = POWER_SUPPLY_STATUS_FULL;
 155                 break;
 156         case POWER_SUPPLY_PROP_PRESENT:
 157                 val->intval = acpi_battery_present(battery);
 158                 break;
 159         case POWER_SUPPLY_PROP_TECHNOLOGY:
 160                 val->intval = acpi_battery_technology(battery);
 161                 break;
 162         case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
 163                 val->intval = battery->design_voltage * 1000;
 164                 break;
 165         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
 166                 val->intval = battery->voltage_now * 1000;
 167                 break;
 168         case POWER_SUPPLY_PROP_CURRENT_NOW:
 169                 val->intval = battery->current_now * 1000;
 170                 break;
 171         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
 172         case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
 173                 val->intval = battery->design_capacity * 1000;
 174                 break;
 175         case POWER_SUPPLY_PROP_CHARGE_FULL:
 176         case POWER_SUPPLY_PROP_ENERGY_FULL:
 177                 val->intval = battery->full_charge_capacity * 1000;
 178                 break;
 179         case POWER_SUPPLY_PROP_CHARGE_NOW:
 180         case POWER_SUPPLY_PROP_ENERGY_NOW:
 181                 val->intval = battery->capacity_now * 1000;
 182                 break;
 183         case POWER_SUPPLY_PROP_MODEL_NAME:
 184                 val->strval = battery->model_number;
 185                 break;
 186         case POWER_SUPPLY_PROP_MANUFACTURER:
 187                 val->strval = battery->oem_info;
 188                 break;
 189         default:
 190                 return -EINVAL;
 191         }
 192         return 0;
 193 }
 194
 195 static enum power_supply_property charge_battery_props[] = {
 196         POWER_SUPPLY_PROP_STATUS,
 197         POWER_SUPPLY_PROP_PRESENT,
 198         POWER_SUPPLY_PROP_TECHNOLOGY,
 199         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 200         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 201         POWER_SUPPLY_PROP_CURRENT_NOW,
 202         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 203         POWER_SUPPLY_PROP_CHARGE_FULL,
 204         POWER_SUPPLY_PROP_CHARGE_NOW,
 205         POWER_SUPPLY_PROP_MODEL_NAME,
 206         POWER_SUPPLY_PROP_MANUFACTURER,
 207 };
 208
 209 static enum power_supply_property energy_battery_props[] = {
 210         POWER_SUPPLY_PROP_STATUS,
 211         POWER_SUPPLY_PROP_PRESENT,
 212         POWER_SUPPLY_PROP_TECHNOLOGY,
 213         POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
 214         POWER_SUPPLY_PROP_VOLTAGE_NOW,
 215         POWER_SUPPLY_PROP_CURRENT_NOW,
 216         POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
 217         POWER_SUPPLY_PROP_ENERGY_FULL,
 218         POWER_SUPPLY_PROP_ENERGY_NOW,
 219         POWER_SUPPLY_PROP_MODEL_NAME,
 220         POWER_SUPPLY_PROP_MANUFACTURER,
 221 };
 222
 223 #ifdef CONFIG_ACPI_PROCFS
 224 inline char *acpi_battery_units(struct acpi_battery *battery)
 225 {
 226         return (battery->power_unit)?"mA":"mW";
 227 }
 228 #endif
 229
 230 /* --------------------------------------------------------------------------
 231                                Battery Management
 232    -------------------------------------------------------------------------- */
 233 struct acpi_offsets {
 234         size_t offset;          /* offset inside struct acpi_sbs_battery */
 235         u8 mode;                /* int or string? */
 236 };
 237
 238 static struct acpi_offsets state_offsets[] = {
 239         {offsetof(struct acpi_battery, state), 0},
 240         {offsetof(struct acpi_battery, current_now), 0},
 241         {offsetof(struct acpi_battery, capacity_now), 0},
 242         {offsetof(struct acpi_battery, voltage_now), 0},
 243 };
 244
 245 static struct acpi_offsets info_offsets[] = {
 246         {offsetof(struct acpi_battery, power_unit), 0},
 247         {offsetof(struct acpi_battery, design_capacity), 0},
 248         {offsetof(struct acpi_battery, full_charge_capacity), 0},
 249         {offsetof(struct acpi_battery, technology), 0},
 250         {offsetof(struct acpi_battery, design_voltage), 0},
 251         {offsetof(struct acpi_battery, design_capacity_warning), 0},
 252         {offsetof(struct acpi_battery, design_capacity_low), 0},
 253         {offsetof(struct acpi_battery, capacity_granularity_1), 0},
 254         {offsetof(struct acpi_battery, capacity_granularity_2), 0},
 255         {offsetof(struct acpi_battery, model_number), 1},
 256         {offsetof(struct acpi_battery, serial_number), 1},
 257         {offsetof(struct acpi_battery, type), 1},
 258         {offsetof(struct acpi_battery, oem_info), 1},
 259 };
 260
 261 static int extract_package(struct acpi_battery *battery,
 262                            union acpi_object *package,
 263                            struct acpi_offsets *offsets, int num)
 264 {
 265         int i;
 266         union acpi_object *element;
 267         if (package->type != ACPI_TYPE_PACKAGE)
 268                 return -EFAULT;
 269         for (i = 0; i < num; ++i) {
 270                 if (package->package.count <= i)
 271                         return -EFAULT;
 272                 element = &package->package.elements[i];
 273                 if (offsets[i].mode) {
 274                         u8 *ptr = (u8 *)battery + offsets[i].offset;
 275                         if (element->type == ACPI_TYPE_STRING ||
 276                             element->type == ACPI_TYPE_BUFFER)
 277                                 strncpy(ptr, element->string.pointer, 32);
 278                         else if (element->type == ACPI_TYPE_INTEGER) {
 279                                 strncpy(ptr, (u8 *)&element->integer.value,
 280                                         sizeof(acpi_integer));
 281                                 ptr[sizeof(acpi_integer)] = 0;
 282                         } else return -EFAULT;
 283                 } else {
 284                         if (element->type == ACPI_TYPE_INTEGER) {
 285                                 int *x = (int *)((u8 *)battery +
 286                                                 offsets[i].offset);
 287                                 *x = element->integer.value;
 288                         } else return -EFAULT;
 289                 }
 290         }
 291         return 0;
 292 }
 293
 294 static int acpi_battery_get_status(struct acpi_battery *battery)
 295 {
 296         if (acpi_bus_get_status(battery->device)) {
 297                 ACPI_EXCEPTION((AE_INFO, AE_ERROR, "Evaluating _STA"));
 298                 return -ENODEV;
 299         }
 300         return 0;
 301 }
 302
 303 static int acpi_battery_get_info(struct acpi_battery *battery)
 304 {
 305         int result = -EFAULT;
 306         acpi_status status = 0;
 307         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 308
 309         if (!acpi_battery_present(battery))
 310                 return 0;
 311         mutex_lock(&battery->lock);
 312         status = acpi_evaluate_object(battery->device->handle, "_BIF",
 313                                       NULL, &buffer);
 314         mutex_unlock(&battery->lock);
 315
 316         if (ACPI_FAILURE(status)) {
 317                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BIF"));
 318                 return -ENODEV;
 319         }
 320
 321         result = extract_package(battery, buffer.pointer,
 322                                  info_offsets, ARRAY_SIZE(info_offsets));
 323         kfree(buffer.pointer);
 324         return result;
 325 }
 326
 327 static int acpi_battery_get_state(struct acpi_battery *battery)
 328 {
 329         int result = 0;
 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
 336         if (battery->update_time &&
 337             time_before(jiffies, battery->update_time +
 338                         msecs_to_jiffies(cache_time)))
 339                 return 0;
 340
 341         mutex_lock(&battery->lock);
 342         status = acpi_evaluate_object(battery->device->handle, "_BST",
 343                                       NULL, &buffer);
 344         mutex_unlock(&battery->lock);
 345
 346         if (ACPI_FAILURE(status)) {
 347                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BST"));
 348                 return -ENODEV;
 349         }
 350
 351         result = extract_package(battery, buffer.pointer,
 352                                  state_offsets, ARRAY_SIZE(state_offsets));
 353         battery->update_time = jiffies;
 354         kfree(buffer.pointer);
 355         return result;
 356 }
 357
 358 static int acpi_battery_set_alarm(struct acpi_battery *battery)
 359 {
 360         acpi_status status = 0;
 361         union acpi_object arg0 = { .type = ACPI_TYPE_INTEGER };
 362         struct acpi_object_list arg_list = { 1, &arg0 };
 363
 364         if (!acpi_battery_present(battery)|| !battery->alarm_present)
 365                 return -ENODEV;
 366
 367         arg0.integer.value = battery->alarm;
 368
 369         mutex_lock(&battery->lock);
 370         status = acpi_evaluate_object(battery->device->handle, "_BTP",
 371                                  &arg_list, NULL);
 372         mutex_unlock(&battery->lock);
 373
 374         if (ACPI_FAILURE(status))
 375                 return -ENODEV;
 376
 377         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Alarm set to %d\n", battery->alarm));
 378         return 0;
 379 }
 380
 381 static int acpi_battery_init_alarm(struct acpi_battery *battery)
 382 {
 383         acpi_status status = AE_OK;
 384         acpi_handle handle = NULL;
 385
 386         /* See if alarms are supported, and if so, set default */
 387         status = acpi_get_handle(battery->device->handle, "_BTP", &handle);
 388         if (ACPI_FAILURE(status)) {
 389                 battery->alarm_present = 0;
 390                 return 0;
 391         }
 392         battery->alarm_present = 1;
 393         if (!battery->alarm)
 394                 battery->alarm = battery->design_capacity_warning;
 395         return acpi_battery_set_alarm(battery);
 396 }
 397
 398 static ssize_t acpi_battery_alarm_show(struct device *dev,
 399                                         struct device_attribute *attr,
 400                                         char *buf)
 401 {
 402         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
 403         return sprintf(buf, "%d\n", battery->alarm * 1000);
 404 }
 405
 406 static ssize_t acpi_battery_alarm_store(struct device *dev,
 407                                         struct device_attribute *attr,
 408                                         const char *buf, size_t count)
 409 {
 410         unsigned long x;
 411         struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
 412         if (sscanf(buf, "%ld\n", &x) == 1)
 413                 battery->alarm = x/1000;
 414         if (acpi_battery_present(battery))
 415                 acpi_battery_set_alarm(battery);
 416         return count;
 417 }
 418
 419 static struct device_attribute alarm_attr = {
 420         .attr = {.name = "alarm", .mode = 0644, .owner = THIS_MODULE},
 421         .show = acpi_battery_alarm_show,
 422         .store = acpi_battery_alarm_store,
 423 };
 424
 425 static int sysfs_add_battery(struct acpi_battery *battery)
 426 {
 427         int result;
 428
 429         battery->update_time = 0;
 430         result = acpi_battery_get_info(battery);
 431         acpi_battery_init_alarm(battery);
 432         if (result)
 433                 return result;
 434         if (battery->power_unit) {
 435                 battery->bat.properties = charge_battery_props;
 436                 battery->bat.num_properties =
 437                         ARRAY_SIZE(charge_battery_props);
 438         } else {
 439                 battery->bat.properties = energy_battery_props;
 440                 battery->bat.num_properties =
 441                         ARRAY_SIZE(energy_battery_props);
 442         }
 443
 444         battery->bat.name = acpi_device_bid(battery->device);
 445         battery->bat.type = POWER_SUPPLY_TYPE_BATTERY;
 446         battery->bat.get_property = acpi_battery_get_property;
 447
 448         result = power_supply_register(&battery->device->dev, &battery->bat);
 449         if (result)
 450                 return result;
 451         return device_create_file(battery->bat.dev, &alarm_attr);
 452 }
 453
 454 static void sysfs_remove_battery(struct acpi_battery *battery)
 455 {
 456         if (!battery->bat.dev)
 457                 return;
 458         device_remove_file(battery->bat.dev, &alarm_attr);
 459         power_supply_unregister(&battery->bat);
 460 }
 461
 462 static int acpi_battery_update(struct acpi_battery *battery)
 463 {
 464         int result = acpi_battery_get_status(battery);
 465         if (result)
 466                 return result;
 467         if (!acpi_battery_present(battery)) {
 468                 sysfs_remove_battery(battery);
 469                 return 0;
 470         }
 471         if (!battery->bat.dev)
 472                 sysfs_add_battery(battery);
 473         return acpi_battery_get_state(battery);
 474 }
 475
 476 /* --------------------------------------------------------------------------
 477                               FS Interface (/proc)
 478    -------------------------------------------------------------------------- */
 479
 480 #ifdef CONFIG_ACPI_PROCFS
 481 static struct proc_dir_entry *acpi_battery_dir;
 482
 483 static int acpi_battery_print_info(struct seq_file *seq, int result)
 484 {
 485         struct acpi_battery *battery = seq->private;
 486
 487         if (result)
 488                 goto end;
 489
 490         seq_printf(seq, "present:                 %s\n",
 491                    acpi_battery_present(battery)?"yes":"no");
 492         if (!acpi_battery_present(battery))
 493                 goto end;
 494         if (battery->design_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
 495                 seq_printf(seq, "design capacity:         unknown\n");
 496         else
 497                 seq_printf(seq, "design capacity:         %d %sh\n",
 498                            battery->design_capacity,
 499                            acpi_battery_units(battery));
 500
 501         if (battery->full_charge_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
 502                 seq_printf(seq, "last full capacity:      unknown\n");
 503         else
 504                 seq_printf(seq, "last full capacity:      %d %sh\n",
 505                            battery->full_charge_capacity,
 506                            acpi_battery_units(battery));
 507
 508         seq_printf(seq, "battery technology:      %srechargeable\n",
 509                    (!battery->technology)?"non-":"");
 510
 511         if (battery->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
 512                 seq_printf(seq, "design voltage:          unknown\n");
 513         else
 514                 seq_printf(seq, "design voltage:          %d mV\n",
 515                            battery->design_voltage);
 516         seq_printf(seq, "design capacity warning: %d %sh\n",
 517                    battery->design_capacity_warning,
 518                    acpi_battery_units(battery));
 519         seq_printf(seq, "design capacity low:     %d %sh\n",
 520                    battery->design_capacity_low,
 521                    acpi_battery_units(battery));
 522         seq_printf(seq, "capacity granularity 1:  %d %sh\n",
 523                    battery->capacity_granularity_1,
 524                    acpi_battery_units(battery));
 525         seq_printf(seq, "capacity granularity 2:  %d %sh\n",
 526                    battery->capacity_granularity_2,
 527                    acpi_battery_units(battery));
 528         seq_printf(seq, "model number:            %s\n", battery->model_number);
 529         seq_printf(seq, "serial number:           %s\n", battery->serial_number);
 530         seq_printf(seq, "battery type:            %s\n", battery->type);
 531         seq_printf(seq, "OEM info:                %s\n", battery->oem_info);
 532       end:
 533         if (result)
 534                 seq_printf(seq, "ERROR: Unable to read battery info\n");
 535         return result;
 536 }
 537
 538 static int acpi_battery_print_state(struct seq_file *seq, int result)
 539 {
 540         struct acpi_battery *battery = seq->private;
 541
 542         if (result)
 543                 goto end;
 544
 545         seq_printf(seq, "present:                 %s\n",
 546                    acpi_battery_present(battery)?"yes":"no");
 547         if (!acpi_battery_present(battery))
 548                 goto end;
 549
 550         seq_printf(seq, "capacity state:          %s\n",
 551                         (battery->state & 0x04)?"critical":"ok");
 552         if ((battery->state & 0x01) && (battery->state & 0x02))
 553                 seq_printf(seq,
 554                            "charging state:          charging/discharging\n");
 555         else if (battery->state & 0x01)
 556                 seq_printf(seq, "charging state:          discharging\n");
 557         else if (battery->state & 0x02)
 558                 seq_printf(seq, "charging state:          charging\n");
 559         else
 560                 seq_printf(seq, "charging state:          charged\n");
 561
 562         if (battery->current_now == ACPI_BATTERY_VALUE_UNKNOWN)
 563                 seq_printf(seq, "present rate:            unknown\n");
 564         else
 565                 seq_printf(seq, "present rate:            %d %s\n",
 566                            battery->current_now, acpi_battery_units(battery));
 567
 568         if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN)
 569                 seq_printf(seq, "remaining capacity:      unknown\n");
 570         else
 571                 seq_printf(seq, "remaining capacity:      %d %sh\n",
 572                            battery->capacity_now, acpi_battery_units(battery));
 573         if (battery->voltage_now == ACPI_BATTERY_VALUE_UNKNOWN)
 574                 seq_printf(seq, "present voltage:         unknown\n");
 575         else
 576                 seq_printf(seq, "present voltage:         %d mV\n",
 577                            battery->voltage_now);
 578       end:
 579         if (result)
 580                 seq_printf(seq, "ERROR: Unable to read battery state\n");
 581
 582         return result;
 583 }
 584
 585 static int acpi_battery_print_alarm(struct seq_file *seq, int result)
 586 {
 587         struct acpi_battery *battery = seq->private;
 588
 589         if (result)
 590                 goto end;
 591
 592         if (!acpi_battery_present(battery)) {
 593                 seq_printf(seq, "present:                 no\n");
 594                 goto end;
 595         }
 596         seq_printf(seq, "alarm:                   ");
 597         if (!battery->alarm)
 598                 seq_printf(seq, "unsupported\n");
 599         else
 600                 seq_printf(seq, "%u %sh\n", battery->alarm,
 601                                 acpi_battery_units(battery));
 602       end:
 603         if (result)
 604                 seq_printf(seq, "ERROR: Unable to read battery alarm\n");
 605         return result;
 606 }
 607
 608 static ssize_t acpi_battery_write_alarm(struct file *file,
 609                                         const char __user * buffer,
 610                                         size_t count, loff_t * ppos)
 611 {
 612         int result = 0;
 613         char alarm_string[12] = { '\0' };
 614         struct seq_file *m = file->private_data;
 615         struct acpi_battery *battery = m->private;
 616
 617         if (!battery || (count > sizeof(alarm_string) - 1))
 618                 return -EINVAL;
 619         if (!acpi_battery_present(battery)) {
 620                 result = -ENODEV;
 621                 goto end;
 622         }
 623         if (copy_from_user(alarm_string, buffer, count)) {
 624                 result = -EFAULT;
 625                 goto end;
 626         }
 627         alarm_string[count] = '\0';
 628         battery->alarm = simple_strtol(alarm_string, NULL, 0);
 629         result = acpi_battery_set_alarm(battery);
 630       end:
 631         if (!result)
 632                 return count;
 633         return result;
 634 }
 635
 636 typedef int(*print_func)(struct seq_file *seq, int result);
 637
 638 static print_func acpi_print_funcs[ACPI_BATTERY_NUMFILES] = {
 639         acpi_battery_print_info,
 640         acpi_battery_print_state,
 641         acpi_battery_print_alarm,
 642 };
 643
 644 static int acpi_battery_read(int fid, struct seq_file *seq)
 645 {
 646         struct acpi_battery *battery = seq->private;
 647         int result = acpi_battery_update(battery);
 648         return acpi_print_funcs[fid](seq, result);
 649 }
 650
 651 #define DECLARE_FILE_FUNCTIONS(_name) \
 652 static int acpi_battery_read_##_name(struct seq_file *seq, void *offset) \
 653 { \
 654         return acpi_battery_read(_name##_tag, seq); \
 655 } \
 656 static int acpi_battery_##_name##_open_fs(struct inode *inode, struct file *file) \
 657 { \
 658         return single_open(file, acpi_battery_read_##_name, PDE(inode)->data); \
 659 }
 660
 661 DECLARE_FILE_FUNCTIONS(info);
 662 DECLARE_FILE_FUNCTIONS(state);
 663 DECLARE_FILE_FUNCTIONS(alarm);
 664
 665 #undef DECLARE_FILE_FUNCTIONS
 666
 667 #define FILE_DESCRIPTION_RO(_name) \
 668         { \
 669         .name = __stringify(_name), \
 670         .mode = S_IRUGO, \
 671         .ops = { \
 672                 .open = acpi_battery_##_name##_open_fs, \
 673                 .read = seq_read, \
 674                 .llseek = seq_lseek, \
 675                 .release = single_release, \
 676                 .owner = THIS_MODULE, \
 677                 }, \
 678         }
 679
 680 #define FILE_DESCRIPTION_RW(_name) \
 681         { \
 682         .name = __stringify(_name), \
 683         .mode = S_IFREG | S_IRUGO | S_IWUSR, \
 684         .ops = { \
 685                 .open = acpi_battery_##_name##_open_fs, \
 686                 .read = seq_read, \
 687                 .llseek = seq_lseek, \
 688                 .write = acpi_battery_write_##_name, \
 689                 .release = single_release, \
 690                 .owner = THIS_MODULE, \
 691                 }, \
 692         }
 693
 694 static struct battery_file {
 695         struct file_operations ops;
 696         mode_t mode;
 697         char *name;
 698 } acpi_battery_file[] = {
 699         FILE_DESCRIPTION_RO(info),
 700         FILE_DESCRIPTION_RO(state),
 701         FILE_DESCRIPTION_RW(alarm),
 702 };
 703
 704 #undef FILE_DESCRIPTION_RO
 705 #undef FILE_DESCRIPTION_RW
 706
 707 static int acpi_battery_add_fs(struct acpi_device *device)
 708 {
 709         struct proc_dir_entry *entry = NULL;
 710         int i;
 711
 712         if (!acpi_device_dir(device)) {
 713                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 714                                                      acpi_battery_dir);
 715                 if (!acpi_device_dir(device))
 716                         return -ENODEV;
 717                 acpi_device_dir(device)->owner = THIS_MODULE;
 718         }
 719
 720         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i) {
 721                 entry = create_proc_entry(acpi_battery_file[i].name,
 722                                   acpi_battery_file[i].mode, acpi_device_dir(device));
 723                 if (!entry)
 724                         return -ENODEV;
 725                 else {
 726                         entry->proc_fops = &acpi_battery_file[i].ops;
 727                         entry->data = acpi_driver_data(device);
 728                         entry->owner = THIS_MODULE;
 729                 }
 730         }
 731         return 0;
 732 }
 733
 734 static void acpi_battery_remove_fs(struct acpi_device *device)
 735 {
 736         int i;
 737         if (!acpi_device_dir(device))
 738                 return;
 739         for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i)
 740                 remove_proc_entry(acpi_battery_file[i].name,
 741                                   acpi_device_dir(device));
 742
 743         remove_proc_entry(acpi_device_bid(device), acpi_battery_dir);
 744         acpi_device_dir(device) = NULL;
 745 }
 746
 747 #endif
 748
 749 /* --------------------------------------------------------------------------
 750                                  Driver Interface
 751    -------------------------------------------------------------------------- */
 752
 753 static void acpi_battery_notify(acpi_handle handle, u32 event, void *data)
 754 {
 755         struct acpi_battery *battery = data;
 756         struct acpi_device *device;
 757         if (!battery)
 758                 return;
 759         device = battery->device;
 760         acpi_battery_update(battery);
 761         acpi_bus_generate_proc_event(device, event,
 762                                      acpi_battery_present(battery));
 763         acpi_bus_generate_netlink_event(device->pnp.device_class,
 764                                         device->dev.bus_id, event,
 765                                         acpi_battery_present(battery));
 766         /* acpi_batter_update could remove power_supply object */
 767         if (battery->bat.dev)
 768                 kobject_uevent(&battery->bat.dev->kobj, KOBJ_CHANGE);
 769 }
 770
 771 static int acpi_battery_add(struct acpi_device *device)
 772 {
 773         int result = 0;
 774         acpi_status status = 0;
 775         struct acpi_battery *battery = NULL;
 776         if (!device)
 777                 return -EINVAL;
 778         battery = kzalloc(sizeof(struct acpi_battery), GFP_KERNEL);
 779         if (!battery)
 780                 return -ENOMEM;
 781         battery->device = device;
 782         strcpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
 783         strcpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
 784         acpi_driver_data(device) = battery;
 785         mutex_init(&battery->lock);
 786         acpi_battery_update(battery);
 787 #ifdef CONFIG_ACPI_PROCFS
 788         result = acpi_battery_add_fs(device);
 789         if (result)
 790                 goto end;
 791 #endif
 792         status = acpi_install_notify_handler(device->handle,
 793                                              ACPI_ALL_NOTIFY,
 794                                              acpi_battery_notify, battery);
 795         if (ACPI_FAILURE(status)) {
 796                 ACPI_EXCEPTION((AE_INFO, status, "Installing notify handler"));
 797                 result = -ENODEV;
 798                 goto end;
 799         }
 800         printk(KERN_INFO PREFIX "%s Slot [%s] (battery %s)\n",
 801                ACPI_BATTERY_DEVICE_NAME, acpi_device_bid(device),
 802                device->status.battery_present ? "present" : "absent");
 803       end:
 804         if (result) {
 805 #ifdef CONFIG_ACPI_PROCFS
 806                 acpi_battery_remove_fs(device);
 807 #endif
 808                 kfree(battery);
 809         }
 810         return result;
 811 }
 812
 813 static int acpi_battery_remove(struct acpi_device *device, int type)
 814 {
 815         acpi_status status = 0;
 816         struct acpi_battery *battery = NULL;
 817
 818         if (!device || !acpi_driver_data(device))
 819                 return -EINVAL;
 820         battery = acpi_driver_data(device);
 821         status = acpi_remove_notify_handler(device->handle,
 822                                             ACPI_ALL_NOTIFY,
 823                                             acpi_battery_notify);
 824 #ifdef CONFIG_ACPI_PROCFS
 825         acpi_battery_remove_fs(device);
 826 #endif
 827         sysfs_remove_battery(battery);
 828         mutex_destroy(&battery->lock);
 829         kfree(battery);
 830         return 0;
 831 }
 832
 833 /* this is needed to learn about changes made in suspended state */
 834 static int acpi_battery_resume(struct acpi_device *device)
 835 {
 836         struct acpi_battery *battery;
 837         if (!device)
 838                 return -EINVAL;
 839         battery = acpi_driver_data(device);
 840         battery->update_time = 0;
 841         acpi_battery_update(battery);
 842         return 0;
 843 }
 844
 845 static struct acpi_driver acpi_battery_driver = {
 846         .name = "battery",
 847         .class = ACPI_BATTERY_CLASS,
 848         .ids = battery_device_ids,
 849         .ops = {
 850                 .add = acpi_battery_add,
 851                 .resume = acpi_battery_resume,
 852                 .remove = acpi_battery_remove,
 853                 },
 854 };
 855
 856 static int __init acpi_battery_init(void)
 857 {
 858         if (acpi_disabled)
 859                 return -ENODEV;
 860 #ifdef CONFIG_ACPI_PROCFS
 861         acpi_battery_dir = acpi_lock_battery_dir();
 862         if (!acpi_battery_dir)
 863                 return -ENODEV;
 864 #endif
 865         if (acpi_bus_register_driver(&acpi_battery_driver) < 0) {
 866 #ifdef CONFIG_ACPI_PROCFS
 867                 acpi_unlock_battery_dir(acpi_battery_dir);
 868 #endif
 869                 return -ENODEV;
 870         }
 871         return 0;
 872 }
 873
 874 static void __exit acpi_battery_exit(void)
 875 {
 876         acpi_bus_unregister_driver(&acpi_battery_driver);
 877 #ifdef CONFIG_ACPI_PROCFS
 878         acpi_unlock_battery_dir(acpi_battery_dir);
 879 #endif
 880 }
 881
 882 module_init(acpi_battery_init);
 883 module_exit(acpi_battery_exit);