drivers/acpi/bus.c

   1 /*
   2  *  acpi_bus.c - ACPI Bus Driver ($Revision: 80 $)
   3  *
   4  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   5  *
   6  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   7  *
   8  *  This program is free software; you can redistribute it and/or modify
   9  *  it under the terms of the GNU General Public License as published by
  10  *  the Free Software Foundation; either version 2 of the License, or (at
  11  *  your option) any later version.
  12  *
  13  *  This program is distributed in the hope that it will be useful, but
  14  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  *  General Public License for more details.
  17  *
  18  *  You should have received a copy of the GNU General Public License along
  19  *  with this program; if not, write to the Free Software Foundation, Inc.,
  20  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  21  *
  22  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  23  */
  24
  25 #include <linux/module.h>
  26 #include <linux/init.h>
  27 #include <linux/ioport.h>
  28 #include <linux/list.h>
  29 #include <linux/sched.h>
  30 #include <linux/pm.h>
  31 #include <linux/pm_legacy.h>
  32 #include <linux/device.h>
  33 #include <linux/proc_fs.h>
  34 #ifdef CONFIG_X86
  35 #include <asm/mpspec.h>
  36 #endif
  37 #include <acpi/acpi_bus.h>
  38 #include <acpi/acpi_drivers.h>
  39
  40 #define _COMPONENT              ACPI_BUS_COMPONENT
  41 ACPI_MODULE_NAME("acpi_bus")
  42 #ifdef  CONFIG_X86
  43 extern void __init acpi_pic_sci_set_trigger(unsigned int irq, u16 trigger);
  44 #endif
  45
  46 struct fadt_descriptor acpi_fadt;
  47 EXPORT_SYMBOL(acpi_fadt);
  48
  49 struct acpi_device *acpi_root;
  50 struct proc_dir_entry *acpi_root_dir;
  51 EXPORT_SYMBOL(acpi_root_dir);
  52
  53 #define STRUCT_TO_INT(s)        (*((int*)&s))
  54
  55 /* --------------------------------------------------------------------------
  56                                 Device Management
  57    -------------------------------------------------------------------------- */
  58
  59 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
  60 {
  61         acpi_status status = AE_OK;
  62
  63         ACPI_FUNCTION_TRACE("acpi_bus_get_device");
  64
  65         if (!device)
  66                 return_VALUE(-EINVAL);
  67
  68         /* TBD: Support fixed-feature devices */
  69
  70         status = acpi_get_data(handle, acpi_bus_data_handler, (void **)device);
  71         if (ACPI_FAILURE(status) || !*device) {
  72                 ACPI_DEBUG_PRINT((ACPI_DB_WARN, "No context for object [%p]\n",
  73                                   handle));
  74                 return_VALUE(-ENODEV);
  75         }
  76
  77         return_VALUE(0);
  78 }
  79
  80 EXPORT_SYMBOL(acpi_bus_get_device);
  81
  82 int acpi_bus_get_status(struct acpi_device *device)
  83 {
  84         acpi_status status = AE_OK;
  85         unsigned long sta = 0;
  86
  87         ACPI_FUNCTION_TRACE("acpi_bus_get_status");
  88
  89         if (!device)
  90                 return_VALUE(-EINVAL);
  91
  92         /*
  93          * Evaluate _STA if present.
  94          */
  95         if (device->flags.dynamic_status) {
  96                 status =
  97                     acpi_evaluate_integer(device->handle, "_STA", NULL, &sta);
  98                 if (ACPI_FAILURE(status))
  99                         return_VALUE(-ENODEV);
 100                 STRUCT_TO_INT(device->status) = (int)sta;
 101         }
 102
 103         /*
 104          * Otherwise we assume the status of our parent (unless we don't
 105          * have one, in which case status is implied).
 106          */
 107         else if (device->parent)
 108                 device->status = device->parent->status;
 109         else
 110                 STRUCT_TO_INT(device->status) = 0x0F;
 111
 112         if (device->status.functional && !device->status.present) {
 113                 printk(KERN_WARNING PREFIX "Device [%s] status [%08x]: "
 114                        "functional but not present; setting present\n",
 115                        device->pnp.bus_id, (u32) STRUCT_TO_INT(device->status));
 116                 device->status.present = 1;
 117         }
 118
 119         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]\n",
 120                           device->pnp.bus_id,
 121                           (u32) STRUCT_TO_INT(device->status)));
 122
 123         return_VALUE(0);
 124 }
 125
 126 EXPORT_SYMBOL(acpi_bus_get_status);
 127
 128 /* --------------------------------------------------------------------------
 129                                  Power Management
 130    -------------------------------------------------------------------------- */
 131
 132 int acpi_bus_get_power(acpi_handle handle, int *state)
 133 {
 134         int result = 0;
 135         acpi_status status = 0;
 136         struct acpi_device *device = NULL;
 137         unsigned long psc = 0;
 138
 139         ACPI_FUNCTION_TRACE("acpi_bus_get_power");
 140
 141         result = acpi_bus_get_device(handle, &device);
 142         if (result)
 143                 return_VALUE(result);
 144
 145         *state = ACPI_STATE_UNKNOWN;
 146
 147         if (!device->flags.power_manageable) {
 148                 /* TBD: Non-recursive algorithm for walking up hierarchy */
 149                 if (device->parent)
 150                         *state = device->parent->power.state;
 151                 else
 152                         *state = ACPI_STATE_D0;
 153         } else {
 154                 /*
 155                  * Get the device's power state either directly (via _PSC) or
 156                  * indirectly (via power resources).
 157                  */
 158                 if (device->power.flags.explicit_get) {
 159                         status = acpi_evaluate_integer(device->handle, "_PSC",
 160                                                        NULL, &psc);
 161                         if (ACPI_FAILURE(status))
 162                                 return_VALUE(-ENODEV);
 163                         device->power.state = (int)psc;
 164                 } else if (device->power.flags.power_resources) {
 165                         result = acpi_power_get_inferred_state(device);
 166                         if (result)
 167                                 return_VALUE(result);
 168                 }
 169
 170                 *state = device->power.state;
 171         }
 172
 173         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is D%d\n",
 174                           device->pnp.bus_id, device->power.state));
 175
 176         return_VALUE(0);
 177 }
 178
 179 EXPORT_SYMBOL(acpi_bus_get_power);
 180
 181 int acpi_bus_set_power(acpi_handle handle, int state)
 182 {
 183         int result = 0;
 184         acpi_status status = AE_OK;
 185         struct acpi_device *device = NULL;
 186         char object_name[5] = { '_', 'P', 'S', '0' + state, '\0' };
 187
 188         ACPI_FUNCTION_TRACE("acpi_bus_set_power");
 189
 190         result = acpi_bus_get_device(handle, &device);
 191         if (result)
 192                 return_VALUE(result);
 193
 194         if ((state < ACPI_STATE_D0) || (state > ACPI_STATE_D3))
 195                 return_VALUE(-EINVAL);
 196
 197         /* Make sure this is a valid target state */
 198
 199         if (!device->flags.power_manageable) {
 200                 ACPI_DEBUG_PRINT((ACPI_DB_WARN,
 201                                   "Device is not power manageable\n"));
 202                 return_VALUE(-ENODEV);
 203         }
 204         /*
 205          * Get device's current power state if it's unknown
 206          * This means device power state isn't initialized or previous setting failed
 207          */
 208         if (!device->flags.force_power_state) {
 209                 if (device->power.state == ACPI_STATE_UNKNOWN)
 210                         acpi_bus_get_power(device->handle, &device->power.state);
 211                 if (state == device->power.state) {
 212                         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at D%d\n",
 213                                           state));
 214                         return_VALUE(0);
 215                 }
 216         }
 217         if (!device->power.states[state].flags.valid) {
 218                 ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Device does not support D%d\n",
 219                                   state));
 220                 return_VALUE(-ENODEV);
 221         }
 222         if (device->parent && (state < device->parent->power.state)) {
 223                 ACPI_DEBUG_PRINT((ACPI_DB_WARN,
 224                                   "Cannot set device to a higher-powered state than parent\n"));
 225                 return_VALUE(-ENODEV);
 226         }
 227
 228         /*
 229          * Transition Power
 230          * ----------------
 231          * On transitions to a high-powered state we first apply power (via
 232          * power resources) then evalute _PSx.  Conversly for transitions to
 233          * a lower-powered state.
 234          */
 235         if (state < device->power.state) {
 236                 if (device->power.flags.power_resources) {
 237                         result = acpi_power_transition(device, state);
 238                         if (result)
 239                                 goto end;
 240                 }
 241                 if (device->power.states[state].flags.explicit_set) {
 242                         status = acpi_evaluate_object(device->handle,
 243                                                       object_name, NULL, NULL);
 244                         if (ACPI_FAILURE(status)) {
 245                                 result = -ENODEV;
 246                                 goto end;
 247                         }
 248                 }
 249         } else {
 250                 if (device->power.states[state].flags.explicit_set) {
 251                         status = acpi_evaluate_object(device->handle,
 252                                                       object_name, NULL, NULL);
 253                         if (ACPI_FAILURE(status)) {
 254                                 result = -ENODEV;
 255                                 goto end;
 256                         }
 257                 }
 258                 if (device->power.flags.power_resources) {
 259                         result = acpi_power_transition(device, state);
 260                         if (result)
 261                                 goto end;
 262                 }
 263         }
 264
 265       end:
 266         if (result)
 267                 ACPI_DEBUG_PRINT((ACPI_DB_WARN,
 268                                   "Error transitioning device [%s] to D%d\n",
 269                                   device->pnp.bus_id, state));
 270         else
 271                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 272                                   "Device [%s] transitioned to D%d\n",
 273                                   device->pnp.bus_id, state));
 274
 275         return_VALUE(result);
 276 }
 277
 278 EXPORT_SYMBOL(acpi_bus_set_power);
 279
 280 /* --------------------------------------------------------------------------
 281                                 Event Management
 282    -------------------------------------------------------------------------- */
 283
 284 static DEFINE_SPINLOCK(acpi_bus_event_lock);
 285
 286 LIST_HEAD(acpi_bus_event_list);
 287 DECLARE_WAIT_QUEUE_HEAD(acpi_bus_event_queue);
 288
 289 extern int event_is_open;
 290
 291 int acpi_bus_generate_event(struct acpi_device *device, u8 type, int data)
 292 {
 293         struct acpi_bus_event *event = NULL;
 294         unsigned long flags = 0;
 295
 296         ACPI_FUNCTION_TRACE("acpi_bus_generate_event");
 297
 298         if (!device)
 299                 return_VALUE(-EINVAL);
 300
 301         /* drop event on the floor if no one's listening */
 302         if (!event_is_open)
 303                 return_VALUE(0);
 304
 305         event = kmalloc(sizeof(struct acpi_bus_event), GFP_ATOMIC);
 306         if (!event)
 307                 return_VALUE(-ENOMEM);
 308
 309         strcpy(event->device_class, device->pnp.device_class);
 310         strcpy(event->bus_id, device->pnp.bus_id);
 311         event->type = type;
 312         event->data = data;
 313
 314         spin_lock_irqsave(&acpi_bus_event_lock, flags);
 315         list_add_tail(&event->node, &acpi_bus_event_list);
 316         spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
 317
 318         wake_up_interruptible(&acpi_bus_event_queue);
 319
 320         return_VALUE(0);
 321 }
 322
 323 EXPORT_SYMBOL(acpi_bus_generate_event);
 324
 325 int acpi_bus_receive_event(struct acpi_bus_event *event)
 326 {
 327         unsigned long flags = 0;
 328         struct acpi_bus_event *entry = NULL;
 329
 330         DECLARE_WAITQUEUE(wait, current);
 331
 332         ACPI_FUNCTION_TRACE("acpi_bus_receive_event");
 333
 334         if (!event)
 335                 return_VALUE(-EINVAL);
 336
 337         if (list_empty(&acpi_bus_event_list)) {
 338
 339                 set_current_state(TASK_INTERRUPTIBLE);
 340                 add_wait_queue(&acpi_bus_event_queue, &wait);
 341
 342                 if (list_empty(&acpi_bus_event_list))
 343                         schedule();
 344
 345                 remove_wait_queue(&acpi_bus_event_queue, &wait);
 346                 set_current_state(TASK_RUNNING);
 347
 348                 if (signal_pending(current))
 349                         return_VALUE(-ERESTARTSYS);
 350         }
 351
 352         spin_lock_irqsave(&acpi_bus_event_lock, flags);
 353         entry =
 354             list_entry(acpi_bus_event_list.next, struct acpi_bus_event, node);
 355         if (entry)
 356                 list_del(&entry->node);
 357         spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
 358
 359         if (!entry)
 360                 return_VALUE(-ENODEV);
 361
 362         memcpy(event, entry, sizeof(struct acpi_bus_event));
 363
 364         kfree(entry);
 365
 366         return_VALUE(0);
 367 }
 368
 369 EXPORT_SYMBOL(acpi_bus_receive_event);
 370
 371 /* --------------------------------------------------------------------------
 372                              Notification Handling
 373    -------------------------------------------------------------------------- */
 374
 375 static int
 376 acpi_bus_check_device(struct acpi_device *device, int *status_changed)
 377 {
 378         acpi_status status = 0;
 379         struct acpi_device_status old_status;
 380
 381         ACPI_FUNCTION_TRACE("acpi_bus_check_device");
 382
 383         if (!device)
 384                 return_VALUE(-EINVAL);
 385
 386         if (status_changed)
 387                 *status_changed = 0;
 388
 389         old_status = device->status;
 390
 391         /*
 392          * Make sure this device's parent is present before we go about
 393          * messing with the device.
 394          */
 395         if (device->parent && !device->parent->status.present) {
 396                 device->status = device->parent->status;
 397                 if (STRUCT_TO_INT(old_status) != STRUCT_TO_INT(device->status)) {
 398                         if (status_changed)
 399                                 *status_changed = 1;
 400                 }
 401                 return_VALUE(0);
 402         }
 403
 404         status = acpi_bus_get_status(device);
 405         if (ACPI_FAILURE(status))
 406                 return_VALUE(-ENODEV);
 407
 408         if (STRUCT_TO_INT(old_status) == STRUCT_TO_INT(device->status))
 409                 return_VALUE(0);
 410
 411         if (status_changed)
 412                 *status_changed = 1;
 413
 414         /*
 415          * Device Insertion/Removal
 416          */
 417         if ((device->status.present) && !(old_status.present)) {
 418                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device insertion detected\n"));
 419                 /* TBD: Handle device insertion */
 420         } else if (!(device->status.present) && (old_status.present)) {
 421                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device removal detected\n"));
 422                 /* TBD: Handle device removal */
 423         }
 424
 425         return_VALUE(0);
 426 }
 427
 428 static int acpi_bus_check_scope(struct acpi_device *device)
 429 {
 430         int result = 0;
 431         int status_changed = 0;
 432
 433         ACPI_FUNCTION_TRACE("acpi_bus_check_scope");
 434
 435         if (!device)
 436                 return_VALUE(-EINVAL);
 437
 438         /* Status Change? */
 439         result = acpi_bus_check_device(device, &status_changed);
 440         if (result)
 441                 return_VALUE(result);
 442
 443         if (!status_changed)
 444                 return_VALUE(0);
 445
 446         /*
 447          * TBD: Enumerate child devices within this device's scope and
 448          *       run acpi_bus_check_device()'s on them.
 449          */
 450
 451         return_VALUE(0);
 452 }
 453
 454 /**
 455  * acpi_bus_notify
 456  * ---------------
 457  * Callback for all 'system-level' device notifications (values 0x00-0x7F).
 458  */
 459 static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
 460 {
 461         int result = 0;
 462         struct acpi_device *device = NULL;
 463
 464         ACPI_FUNCTION_TRACE("acpi_bus_notify");
 465
 466         if (acpi_bus_get_device(handle, &device))
 467                 return_VOID;
 468
 469         switch (type) {
 470
 471         case ACPI_NOTIFY_BUS_CHECK:
 472                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 473                                   "Received BUS CHECK notification for device [%s]\n",
 474                                   device->pnp.bus_id));
 475                 result = acpi_bus_check_scope(device);
 476                 /*
 477                  * TBD: We'll need to outsource certain events to non-ACPI
 478                  *      drivers via the device manager (device.c).
 479                  */
 480                 break;
 481
 482         case ACPI_NOTIFY_DEVICE_CHECK:
 483                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 484                                   "Received DEVICE CHECK notification for device [%s]\n",
 485                                   device->pnp.bus_id));
 486                 result = acpi_bus_check_device(device, NULL);
 487                 /*
 488                  * TBD: We'll need to outsource certain events to non-ACPI
 489                  *      drivers via the device manager (device.c).
 490                  */
 491                 break;
 492
 493         case ACPI_NOTIFY_DEVICE_WAKE:
 494                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 495                                   "Received DEVICE WAKE notification for device [%s]\n",
 496                                   device->pnp.bus_id));
 497                 /* TBD */
 498                 break;
 499
 500         case ACPI_NOTIFY_EJECT_REQUEST:
 501                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 502                                   "Received EJECT REQUEST notification for device [%s]\n",
 503                                   device->pnp.bus_id));
 504                 /* TBD */
 505                 break;
 506
 507         case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
 508                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 509                                   "Received DEVICE CHECK LIGHT notification for device [%s]\n",
 510                                   device->pnp.bus_id));
 511                 /* TBD: Exactly what does 'light' mean? */
 512                 break;
 513
 514         case ACPI_NOTIFY_FREQUENCY_MISMATCH:
 515                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 516                                   "Received FREQUENCY MISMATCH notification for device [%s]\n",
 517                                   device->pnp.bus_id));
 518                 /* TBD */
 519                 break;
 520
 521         case ACPI_NOTIFY_BUS_MODE_MISMATCH:
 522                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 523                                   "Received BUS MODE MISMATCH notification for device [%s]\n",
 524                                   device->pnp.bus_id));
 525                 /* TBD */
 526                 break;
 527
 528         case ACPI_NOTIFY_POWER_FAULT:
 529                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 530                                   "Received POWER FAULT notification for device [%s]\n",
 531                                   device->pnp.bus_id));
 532                 /* TBD */
 533                 break;
 534
 535         default:
 536                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 537                                   "Received unknown/unsupported notification [%08x]\n",
 538                                   type));
 539                 break;
 540         }
 541
 542         return_VOID;
 543 }
 544
 545 /* --------------------------------------------------------------------------
 546                              Initialization/Cleanup
 547    -------------------------------------------------------------------------- */
 548
 549 static int __init acpi_bus_init_irq(void)
 550 {
 551         acpi_status status = AE_OK;
 552         union acpi_object arg = { ACPI_TYPE_INTEGER };
 553         struct acpi_object_list arg_list = { 1, &arg };
 554         char *message = NULL;
 555
 556         ACPI_FUNCTION_TRACE("acpi_bus_init_irq");
 557
 558         /*
 559          * Let the system know what interrupt model we are using by
 560          * evaluating the \_PIC object, if exists.
 561          */
 562
 563         switch (acpi_irq_model) {
 564         case ACPI_IRQ_MODEL_PIC:
 565                 message = "PIC";
 566                 break;
 567         case ACPI_IRQ_MODEL_IOAPIC:
 568                 message = "IOAPIC";
 569                 break;
 570         case ACPI_IRQ_MODEL_IOSAPIC:
 571                 message = "IOSAPIC";
 572                 break;
 573         default:
 574                 printk(KERN_WARNING PREFIX "Unknown interrupt routing model\n");
 575                 return_VALUE(-ENODEV);
 576         }
 577
 578         printk(KERN_INFO PREFIX "Using %s for interrupt routing\n", message);
 579
 580         arg.integer.value = acpi_irq_model;
 581
 582         status = acpi_evaluate_object(NULL, "\\_PIC", &arg_list, NULL);
 583         if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
 584                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PIC\n"));
 585                 return_VALUE(-ENODEV);
 586         }
 587
 588         return_VALUE(0);
 589 }
 590
 591 void __init acpi_early_init(void)
 592 {
 593         acpi_status status = AE_OK;
 594         struct acpi_buffer buffer = { sizeof(acpi_fadt), &acpi_fadt };
 595
 596         ACPI_FUNCTION_TRACE("acpi_early_init");
 597
 598         if (acpi_disabled)
 599                 return_VOID;
 600
 601         printk(KERN_INFO PREFIX "Core revision %08x\n", ACPI_CA_VERSION);
 602
 603         /* enable workarounds, unless strict ACPI spec. compliance */
 604         if (!acpi_strict)
 605                 acpi_gbl_enable_interpreter_slack = TRUE;
 606
 607         status = acpi_initialize_subsystem();
 608         if (ACPI_FAILURE(status)) {
 609                 printk(KERN_ERR PREFIX
 610                        "Unable to initialize the ACPI Interpreter\n");
 611                 goto error0;
 612         }
 613
 614         status = acpi_load_tables();
 615         if (ACPI_FAILURE(status)) {
 616                 printk(KERN_ERR PREFIX
 617                        "Unable to load the System Description Tables\n");
 618                 goto error0;
 619         }
 620
 621         /*
 622          * Get a separate copy of the FADT for use by other drivers.
 623          */
 624         status = acpi_get_table(ACPI_TABLE_ID_FADT, 1, &buffer);
 625         if (ACPI_FAILURE(status)) {
 626                 printk(KERN_ERR PREFIX "Unable to get the FADT\n");
 627                 goto error0;
 628         }
 629 #ifdef CONFIG_X86
 630         if (!acpi_ioapic) {
 631                 extern acpi_interrupt_flags acpi_sci_flags;
 632
 633                 /* compatible (0) means level (3) */
 634                 if (acpi_sci_flags.trigger == 0)
 635                         acpi_sci_flags.trigger = 3;
 636
 637                 /* Set PIC-mode SCI trigger type */
 638                 acpi_pic_sci_set_trigger(acpi_fadt.sci_int,
 639                                          acpi_sci_flags.trigger);
 640         } else {
 641                 extern int acpi_sci_override_gsi;
 642                 /*
 643                  * now that acpi_fadt is initialized,
 644                  * update it with result from INT_SRC_OVR parsing
 645                  */
 646                 acpi_fadt.sci_int = acpi_sci_override_gsi;
 647         }
 648 #endif
 649
 650         status =
 651             acpi_enable_subsystem(~
 652                                   (ACPI_NO_HARDWARE_INIT |
 653                                    ACPI_NO_ACPI_ENABLE));
 654         if (ACPI_FAILURE(status)) {
 655                 printk(KERN_ERR PREFIX "Unable to enable ACPI\n");
 656                 goto error0;
 657         }
 658
 659         return_VOID;
 660
 661       error0:
 662         disable_acpi();
 663         return_VOID;
 664 }
 665
 666 static int __init acpi_bus_init(void)
 667 {
 668         int result = 0;
 669         acpi_status status = AE_OK;
 670         extern acpi_status acpi_os_initialize1(void);
 671
 672         ACPI_FUNCTION_TRACE("acpi_bus_init");
 673
 674         status = acpi_os_initialize1();
 675
 676         status =
 677             acpi_enable_subsystem(ACPI_NO_HARDWARE_INIT | ACPI_NO_ACPI_ENABLE);
 678         if (ACPI_FAILURE(status)) {
 679                 printk(KERN_ERR PREFIX
 680                        "Unable to start the ACPI Interpreter\n");
 681                 goto error1;
 682         }
 683
 684         if (ACPI_FAILURE(status)) {
 685                 printk(KERN_ERR PREFIX
 686                        "Unable to initialize ACPI OS objects\n");
 687                 goto error1;
 688         }
 689 #ifdef CONFIG_ACPI_EC
 690         /*
 691          * ACPI 2.0 requires the EC driver to be loaded and work before
 692          * the EC device is found in the namespace (i.e. before acpi_initialize_objects()
 693          * is called).
 694          *
 695          * This is accomplished by looking for the ECDT table, and getting
 696          * the EC parameters out of that.
 697          */
 698         status = acpi_ec_ecdt_probe();
 699         /* Ignore result. Not having an ECDT is not fatal. */
 700 #endif
 701
 702         status = acpi_initialize_objects(ACPI_FULL_INITIALIZATION);
 703         if (ACPI_FAILURE(status)) {
 704                 printk(KERN_ERR PREFIX "Unable to initialize ACPI objects\n");
 705                 goto error1;
 706         }
 707
 708         printk(KERN_INFO PREFIX "Interpreter enabled\n");
 709
 710         /*
 711          * Get the system interrupt model and evaluate \_PIC.
 712          */
 713         result = acpi_bus_init_irq();
 714         if (result)
 715                 goto error1;
 716
 717         /*
 718          * Register the for all standard device notifications.
 719          */
 720         status =
 721             acpi_install_notify_handler(ACPI_ROOT_OBJECT, ACPI_SYSTEM_NOTIFY,
 722                                         &acpi_bus_notify, NULL);
 723         if (ACPI_FAILURE(status)) {
 724                 printk(KERN_ERR PREFIX
 725                        "Unable to register for device notifications\n");
 726                 goto error1;
 727         }
 728
 729         /*
 730          * Create the top ACPI proc directory
 731          */
 732         acpi_root_dir = proc_mkdir(ACPI_BUS_FILE_ROOT, NULL);
 733
 734         return_VALUE(0);
 735
 736         /* Mimic structured exception handling */
 737       error1:
 738         acpi_terminate();
 739         return_VALUE(-ENODEV);
 740 }
 741
 742 decl_subsys(acpi, NULL, NULL);
 743
 744 static int __init acpi_init(void)
 745 {
 746         int result = 0;
 747
 748         ACPI_FUNCTION_TRACE("acpi_init");
 749
 750         if (acpi_disabled) {
 751                 printk(KERN_INFO PREFIX "Interpreter disabled.\n");
 752                 return_VALUE(-ENODEV);
 753         }
 754
 755         firmware_register(&acpi_subsys);
 756
 757         result = acpi_bus_init();
 758
 759         if (!result) {
 760 #ifdef CONFIG_PM_LEGACY
 761                 if (!PM_IS_ACTIVE())
 762                         pm_active = 1;
 763                 else {
 764                         printk(KERN_INFO PREFIX
 765                                "APM is already active, exiting\n");
 766                         disable_acpi();
 767                         result = -ENODEV;
 768                 }
 769 #endif
 770         } else
 771                 disable_acpi();
 772
 773         return_VALUE(result);
 774 }
 775
 776 subsys_initcall(acpi_init);