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