drivers/acpi/bus.c

   1 /*
   2  *  acpi_bus.c - ACPI Bus Driver ($Revision: 80 $)
   3  *
   4  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <[email protected]>
   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/device.h>
  33 #include <linux/proc_fs.h>
  34 #include <linux/acpi.h>
  35 #include <linux/slab.h>
  36 #ifdef CONFIG_X86
  37 #include <asm/mpspec.h>
  38 #endif
  39 #include <linux/pci.h>
  40 #include <acpi/apei.h>
  41 #include <linux/dmi.h>
  42 #include <linux/suspend.h>
  43
  44 #include "internal.h"
  45
  46 #define _COMPONENT              ACPI_BUS_COMPONENT
  47 ACPI_MODULE_NAME("bus");
  48
  49 struct acpi_device *acpi_root;
  50 struct proc_dir_entry *acpi_root_dir;
  51 EXPORT_SYMBOL(acpi_root_dir);
  52
  53 #ifdef CONFIG_X86
  54 static int set_copy_dsdt(const struct dmi_system_id *id)
  55 {
  56         printk(KERN_NOTICE "%s detected - "
  57                 "force copy of DSDT to local memory\n", id->ident);
  58         acpi_gbl_copy_dsdt_locally = 1;
  59         return 0;
  60 }
  61
  62 static struct dmi_system_id dsdt_dmi_table[] __initdata = {
  63         /*
  64          * Invoke DSDT corruption work-around on all Toshiba Satellite.
  65          * https://bugzilla.kernel.org/show_bug.cgi?id=14679
  66          */
  67         {
  68          .callback = set_copy_dsdt,
  69          .ident = "TOSHIBA Satellite",
  70          .matches = {
  71                 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
  72                 DMI_MATCH(DMI_PRODUCT_NAME, "Satellite"),
  73                 },
  74         },
  75         {}
  76 };
  77 #else
  78 static struct dmi_system_id dsdt_dmi_table[] __initdata = {
  79         {}
  80 };
  81 #endif
  82
  83 /* --------------------------------------------------------------------------
  84                                 Device Management
  85    -------------------------------------------------------------------------- */
  86
  87 acpi_status acpi_bus_get_status_handle(acpi_handle handle,
  88                                        unsigned long long *sta)
  89 {
  90         acpi_status status;
  91
  92         status = acpi_evaluate_integer(handle, "_STA", NULL, sta);
  93         if (ACPI_SUCCESS(status))
  94                 return AE_OK;
  95
  96         if (status == AE_NOT_FOUND) {
  97                 *sta = ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED |
  98                        ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING;
  99                 return AE_OK;
 100         }
 101         return status;
 102 }
 103
 104 int acpi_bus_get_status(struct acpi_device *device)
 105 {
 106         acpi_status status;
 107         unsigned long long sta;
 108
 109         status = acpi_bus_get_status_handle(device->handle, &sta);
 110         if (ACPI_FAILURE(status))
 111                 return -ENODEV;
 112
 113         acpi_set_device_status(device, sta);
 114
 115         if (device->status.functional && !device->status.present) {
 116                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]: "
 117                        "functional but not present;\n",
 118                         device->pnp.bus_id, (u32)sta));
 119         }
 120
 121         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]\n",
 122                           device->pnp.bus_id, (u32)sta));
 123         return 0;
 124 }
 125 EXPORT_SYMBOL(acpi_bus_get_status);
 126
 127 void acpi_bus_private_data_handler(acpi_handle handle,
 128                                    void *context)
 129 {
 130         return;
 131 }
 132 EXPORT_SYMBOL(acpi_bus_private_data_handler);
 133
 134 int acpi_bus_get_private_data(acpi_handle handle, void **data)
 135 {
 136         acpi_status status;
 137
 138         if (!*data)
 139                 return -EINVAL;
 140
 141         status = acpi_get_data(handle, acpi_bus_private_data_handler, data);
 142         if (ACPI_FAILURE(status) || !*data) {
 143                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
 144                                 handle));
 145                 return -ENODEV;
 146         }
 147
 148         return 0;
 149 }
 150 EXPORT_SYMBOL(acpi_bus_get_private_data);
 151
 152 void acpi_bus_no_hotplug(acpi_handle handle)
 153 {
 154         struct acpi_device *adev = NULL;
 155
 156         acpi_bus_get_device(handle, &adev);
 157         if (adev)
 158                 adev->flags.no_hotplug = true;
 159 }
 160 EXPORT_SYMBOL_GPL(acpi_bus_no_hotplug);
 161
 162 static void acpi_print_osc_error(acpi_handle handle,
 163         struct acpi_osc_context *context, char *error)
 164 {
 165         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER};
 166         int i;
 167
 168         if (ACPI_FAILURE(acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer)))
 169                 printk(KERN_DEBUG "%s\n", error);
 170         else {
 171                 printk(KERN_DEBUG "%s:%s\n", (char *)buffer.pointer, error);
 172                 kfree(buffer.pointer);
 173         }
 174         printk(KERN_DEBUG"_OSC request data:");
 175         for (i = 0; i < context->cap.length; i += sizeof(u32))
 176                 printk("%x ", *((u32 *)(context->cap.pointer + i)));
 177         printk("\n");
 178 }
 179
 180 acpi_status acpi_str_to_uuid(char *str, u8 *uuid)
 181 {
 182         int i;
 183         static int opc_map_to_uuid[16] = {6, 4, 2, 0, 11, 9, 16, 14, 19, 21,
 184                 24, 26, 28, 30, 32, 34};
 185
 186         if (strlen(str) != 36)
 187                 return AE_BAD_PARAMETER;
 188         for (i = 0; i < 36; i++) {
 189                 if (i == 8 || i == 13 || i == 18 || i == 23) {
 190                         if (str[i] != '-')
 191                                 return AE_BAD_PARAMETER;
 192                 } else if (!isxdigit(str[i]))
 193                         return AE_BAD_PARAMETER;
 194         }
 195         for (i = 0; i < 16; i++) {
 196                 uuid[i] = hex_to_bin(str[opc_map_to_uuid[i]]) << 4;
 197                 uuid[i] |= hex_to_bin(str[opc_map_to_uuid[i] + 1]);
 198         }
 199         return AE_OK;
 200 }
 201 EXPORT_SYMBOL_GPL(acpi_str_to_uuid);
 202
 203 acpi_status acpi_run_osc(acpi_handle handle, struct acpi_osc_context *context)
 204 {
 205         acpi_status status;
 206         struct acpi_object_list input;
 207         union acpi_object in_params[4];
 208         union acpi_object *out_obj;
 209         u8 uuid[16];
 210         u32 errors;
 211         struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
 212
 213         if (!context)
 214                 return AE_ERROR;
 215         if (ACPI_FAILURE(acpi_str_to_uuid(context->uuid_str, uuid)))
 216                 return AE_ERROR;
 217         context->ret.length = ACPI_ALLOCATE_BUFFER;
 218         context->ret.pointer = NULL;
 219
 220         /* Setting up input parameters */
 221         input.count = 4;
 222         input.pointer = in_params;
 223         in_params[0].type               = ACPI_TYPE_BUFFER;
 224         in_params[0].buffer.length      = 16;
 225         in_params[0].buffer.pointer     = uuid;
 226         in_params[1].type               = ACPI_TYPE_INTEGER;
 227         in_params[1].integer.value      = context->rev;
 228         in_params[2].type               = ACPI_TYPE_INTEGER;
 229         in_params[2].integer.value      = context->cap.length/sizeof(u32);
 230         in_params[3].type               = ACPI_TYPE_BUFFER;
 231         in_params[3].buffer.length      = context->cap.length;
 232         in_params[3].buffer.pointer     = context->cap.pointer;
 233
 234         status = acpi_evaluate_object(handle, "_OSC", &input, &output);
 235         if (ACPI_FAILURE(status))
 236                 return status;
 237
 238         if (!output.length)
 239                 return AE_NULL_OBJECT;
 240
 241         out_obj = output.pointer;
 242         if (out_obj->type != ACPI_TYPE_BUFFER
 243                 || out_obj->buffer.length != context->cap.length) {
 244                 acpi_print_osc_error(handle, context,
 245                         "_OSC evaluation returned wrong type");
 246                 status = AE_TYPE;
 247                 goto out_kfree;
 248         }
 249         /* Need to ignore the bit0 in result code */
 250         errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0);
 251         if (errors) {
 252                 if (errors & OSC_REQUEST_ERROR)
 253                         acpi_print_osc_error(handle, context,
 254                                 "_OSC request failed");
 255                 if (errors & OSC_INVALID_UUID_ERROR)
 256                         acpi_print_osc_error(handle, context,
 257                                 "_OSC invalid UUID");
 258                 if (errors & OSC_INVALID_REVISION_ERROR)
 259                         acpi_print_osc_error(handle, context,
 260                                 "_OSC invalid revision");
 261                 if (errors & OSC_CAPABILITIES_MASK_ERROR) {
 262                         if (((u32 *)context->cap.pointer)[OSC_QUERY_DWORD]
 263                             & OSC_QUERY_ENABLE)
 264                                 goto out_success;
 265                         status = AE_SUPPORT;
 266                         goto out_kfree;
 267                 }
 268                 status = AE_ERROR;
 269                 goto out_kfree;
 270         }
 271 out_success:
 272         context->ret.length = out_obj->buffer.length;
 273         context->ret.pointer = kmemdup(out_obj->buffer.pointer,
 274                                        context->ret.length, GFP_KERNEL);
 275         if (!context->ret.pointer) {
 276                 status =  AE_NO_MEMORY;
 277                 goto out_kfree;
 278         }
 279         status =  AE_OK;
 280
 281 out_kfree:
 282         kfree(output.pointer);
 283         if (status != AE_OK)
 284                 context->ret.pointer = NULL;
 285         return status;
 286 }
 287 EXPORT_SYMBOL(acpi_run_osc);
 288
 289 bool osc_sb_apei_support_acked;
 290 static u8 sb_uuid_str[] = "0811B06E-4A27-44F9-8D60-3CBBC22E7B48";
 291 static void acpi_bus_osc_support(void)
 292 {
 293         u32 capbuf[2];
 294         struct acpi_osc_context context = {
 295                 .uuid_str = sb_uuid_str,
 296                 .rev = 1,
 297                 .cap.length = 8,
 298                 .cap.pointer = capbuf,
 299         };
 300         acpi_handle handle;
 301
 302         capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
 303         capbuf[OSC_SUPPORT_DWORD] = OSC_SB_PR3_SUPPORT; /* _PR3 is in use */
 304 #if defined(CONFIG_ACPI_PROCESSOR_AGGREGATOR) ||\
 305                         defined(CONFIG_ACPI_PROCESSOR_AGGREGATOR_MODULE)
 306         capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_PAD_SUPPORT;
 307 #endif
 308
 309 #if defined(CONFIG_ACPI_PROCESSOR) || defined(CONFIG_ACPI_PROCESSOR_MODULE)
 310         capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_PPC_OST_SUPPORT;
 311 #endif
 312
 313 #ifdef ACPI_HOTPLUG_OST
 314         capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_HOTPLUG_OST_SUPPORT;
 315 #endif
 316
 317         if (!ghes_disable)
 318                 capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_APEI_SUPPORT;
 319         if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle)))
 320                 return;
 321         if (ACPI_SUCCESS(acpi_run_osc(handle, &context))) {
 322                 u32 *capbuf_ret = context.ret.pointer;
 323                 if (context.ret.length > OSC_SUPPORT_DWORD)
 324                         osc_sb_apei_support_acked =
 325                                 capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_APEI_SUPPORT;
 326                 kfree(context.ret.pointer);
 327         }
 328         /* do we need to check other returned cap? Sounds no */
 329 }
 330
 331 /* --------------------------------------------------------------------------
 332                              Notification Handling
 333    -------------------------------------------------------------------------- */
 334
 335 /**
 336  * acpi_bus_notify
 337  * ---------------
 338  * Callback for all 'system-level' device notifications (values 0x00-0x7F).
 339  */
 340 static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
 341 {
 342         struct acpi_device *device = NULL;
 343         struct acpi_driver *driver;
 344
 345         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Notification %#02x to handle %p\n",
 346                           type, handle));
 347
 348         switch (type) {
 349
 350         case ACPI_NOTIFY_BUS_CHECK:
 351                 /* TBD */
 352                 break;
 353
 354         case ACPI_NOTIFY_DEVICE_CHECK:
 355                 /* TBD */
 356                 break;
 357
 358         case ACPI_NOTIFY_DEVICE_WAKE:
 359                 /* TBD */
 360                 break;
 361
 362         case ACPI_NOTIFY_EJECT_REQUEST:
 363                 /* TBD */
 364                 break;
 365
 366         case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
 367                 /* TBD: Exactly what does 'light' mean? */
 368                 break;
 369
 370         case ACPI_NOTIFY_FREQUENCY_MISMATCH:
 371                 /* TBD */
 372                 break;
 373
 374         case ACPI_NOTIFY_BUS_MODE_MISMATCH:
 375                 /* TBD */
 376                 break;
 377
 378         case ACPI_NOTIFY_POWER_FAULT:
 379                 /* TBD */
 380                 break;
 381
 382         default:
 383                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 384                                   "Received unknown/unsupported notification [%08x]\n",
 385                                   type));
 386                 break;
 387         }
 388
 389         acpi_bus_get_device(handle, &device);
 390         if (device) {
 391                 driver = device->driver;
 392                 if (driver && driver->ops.notify &&
 393                     (driver->flags & ACPI_DRIVER_ALL_NOTIFY_EVENTS))
 394                         driver->ops.notify(device, type);
 395         }
 396 }
 397
 398 /* --------------------------------------------------------------------------
 399                              Initialization/Cleanup
 400    -------------------------------------------------------------------------- */
 401
 402 static int __init acpi_bus_init_irq(void)
 403 {
 404         acpi_status status;
 405         char *message = NULL;
 406
 407
 408         /*
 409          * Let the system know what interrupt model we are using by
 410          * evaluating the \_PIC object, if exists.
 411          */
 412
 413         switch (acpi_irq_model) {
 414         case ACPI_IRQ_MODEL_PIC:
 415                 message = "PIC";
 416                 break;
 417         case ACPI_IRQ_MODEL_IOAPIC:
 418                 message = "IOAPIC";
 419                 break;
 420         case ACPI_IRQ_MODEL_IOSAPIC:
 421                 message = "IOSAPIC";
 422                 break;
 423         case ACPI_IRQ_MODEL_PLATFORM:
 424                 message = "platform specific model";
 425                 break;
 426         default:
 427                 printk(KERN_WARNING PREFIX "Unknown interrupt routing model\n");
 428                 return -ENODEV;
 429         }
 430
 431         printk(KERN_INFO PREFIX "Using %s for interrupt routing\n", message);
 432
 433         status = acpi_execute_simple_method(NULL, "\\_PIC", acpi_irq_model);
 434         if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
 435                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PIC"));
 436                 return -ENODEV;
 437         }
 438
 439         return 0;
 440 }
 441
 442 u8 acpi_gbl_permanent_mmap;
 443
 444
 445 void __init acpi_early_init(void)
 446 {
 447         acpi_status status;
 448
 449         if (acpi_disabled)
 450                 return;
 451
 452         printk(KERN_INFO PREFIX "Core revision %08x\n", ACPI_CA_VERSION);
 453
 454         /* enable workarounds, unless strict ACPI spec. compliance */
 455         if (!acpi_strict)
 456                 acpi_gbl_enable_interpreter_slack = TRUE;
 457
 458         acpi_gbl_permanent_mmap = 1;
 459
 460         /*
 461          * If the machine falls into the DMI check table,
 462          * DSDT will be copied to memory
 463          */
 464         dmi_check_system(dsdt_dmi_table);
 465
 466         status = acpi_reallocate_root_table();
 467         if (ACPI_FAILURE(status)) {
 468                 printk(KERN_ERR PREFIX
 469                        "Unable to reallocate ACPI tables\n");
 470                 goto error0;
 471         }
 472
 473         status = acpi_initialize_subsystem();
 474         if (ACPI_FAILURE(status)) {
 475                 printk(KERN_ERR PREFIX
 476                        "Unable to initialize the ACPI Interpreter\n");
 477                 goto error0;
 478         }
 479
 480         status = acpi_load_tables();
 481         if (ACPI_FAILURE(status)) {
 482                 printk(KERN_ERR PREFIX
 483                        "Unable to load the System Description Tables\n");
 484                 goto error0;
 485         }
 486
 487 #ifdef CONFIG_X86
 488         if (!acpi_ioapic) {
 489                 /* compatible (0) means level (3) */
 490                 if (!(acpi_sci_flags & ACPI_MADT_TRIGGER_MASK)) {
 491                         acpi_sci_flags &= ~ACPI_MADT_TRIGGER_MASK;
 492                         acpi_sci_flags |= ACPI_MADT_TRIGGER_LEVEL;
 493                 }
 494                 /* Set PIC-mode SCI trigger type */
 495                 acpi_pic_sci_set_trigger(acpi_gbl_FADT.sci_interrupt,
 496                                          (acpi_sci_flags & ACPI_MADT_TRIGGER_MASK) >> 2);
 497         } else {
 498                 /*
 499                  * now that acpi_gbl_FADT is initialized,
 500                  * update it with result from INT_SRC_OVR parsing
 501                  */
 502                 acpi_gbl_FADT.sci_interrupt = acpi_sci_override_gsi;
 503         }
 504 #endif
 505
 506         status = acpi_enable_subsystem(~ACPI_NO_ACPI_ENABLE);
 507         if (ACPI_FAILURE(status)) {
 508                 printk(KERN_ERR PREFIX "Unable to enable ACPI\n");
 509                 goto error0;
 510         }
 511
 512         return;
 513
 514       error0:
 515         disable_acpi();
 516         return;
 517 }
 518
 519 static int __init acpi_bus_init(void)
 520 {
 521         int result;
 522         acpi_status status;
 523
 524         acpi_os_initialize1();
 525
 526         status = acpi_enable_subsystem(ACPI_NO_ACPI_ENABLE);
 527         if (ACPI_FAILURE(status)) {
 528                 printk(KERN_ERR PREFIX
 529                        "Unable to start the ACPI Interpreter\n");
 530                 goto error1;
 531         }
 532
 533         /*
 534          * ACPI 2.0 requires the EC driver to be loaded and work before
 535          * the EC device is found in the namespace (i.e. before acpi_initialize_objects()
 536          * is called).
 537          *
 538          * This is accomplished by looking for the ECDT table, and getting
 539          * the EC parameters out of that.
 540          */
 541         status = acpi_ec_ecdt_probe();
 542         /* Ignore result. Not having an ECDT is not fatal. */
 543
 544         status = acpi_initialize_objects(ACPI_FULL_INITIALIZATION);
 545         if (ACPI_FAILURE(status)) {
 546                 printk(KERN_ERR PREFIX "Unable to initialize ACPI objects\n");
 547                 goto error1;
 548         }
 549
 550         /*
 551          * _OSC method may exist in module level code,
 552          * so it must be run after ACPI_FULL_INITIALIZATION
 553          */
 554         acpi_bus_osc_support();
 555
 556         /*
 557          * _PDC control method may load dynamic SSDT tables,
 558          * and we need to install the table handler before that.
 559          */
 560         acpi_sysfs_init();
 561
 562         acpi_early_processor_set_pdc();
 563
 564         /*
 565          * Maybe EC region is required at bus_scan/acpi_get_devices. So it
 566          * is necessary to enable it as early as possible.
 567          */
 568         acpi_boot_ec_enable();
 569
 570         printk(KERN_INFO PREFIX "Interpreter enabled\n");
 571
 572         /* Initialize sleep structures */
 573         acpi_sleep_init();
 574
 575         /*
 576          * Get the system interrupt model and evaluate \_PIC.
 577          */
 578         result = acpi_bus_init_irq();
 579         if (result)
 580                 goto error1;
 581
 582         /*
 583          * Register the for all standard device notifications.
 584          */
 585         status =
 586             acpi_install_notify_handler(ACPI_ROOT_OBJECT, ACPI_SYSTEM_NOTIFY,
 587                                         &acpi_bus_notify, NULL);
 588         if (ACPI_FAILURE(status)) {
 589                 printk(KERN_ERR PREFIX
 590                        "Unable to register for device notifications\n");
 591                 goto error1;
 592         }
 593
 594         /*
 595          * Create the top ACPI proc directory
 596          */
 597         acpi_root_dir = proc_mkdir(ACPI_BUS_FILE_ROOT, NULL);
 598
 599         return 0;
 600
 601         /* Mimic structured exception handling */
 602       error1:
 603         acpi_terminate();
 604         return -ENODEV;
 605 }
 606
 607 struct kobject *acpi_kobj;
 608 EXPORT_SYMBOL_GPL(acpi_kobj);
 609
 610 static int __init acpi_init(void)
 611 {
 612         int result;
 613
 614         if (acpi_disabled) {
 615                 printk(KERN_INFO PREFIX "Interpreter disabled.\n");
 616                 return -ENODEV;
 617         }
 618
 619         acpi_kobj = kobject_create_and_add("acpi", firmware_kobj);
 620         if (!acpi_kobj) {
 621                 printk(KERN_WARNING "%s: kset create error\n", __func__);
 622                 acpi_kobj = NULL;
 623         }
 624
 625         init_acpi_device_notify();
 626         result = acpi_bus_init();
 627         if (result) {
 628                 disable_acpi();
 629                 return result;
 630         }
 631
 632         pci_mmcfg_late_init();
 633         acpi_scan_init();
 634         acpi_ec_init();
 635         acpi_debugfs_init();
 636         acpi_sleep_proc_init();
 637         acpi_wakeup_device_init();
 638         return 0;
 639 }
 640
 641 subsys_initcall(acpi_init);