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