err.no Git - linux-2.6/blob - drivers/acpi/scan.c

   1 /*
   2  * scan.c - support for transforming the ACPI namespace into individual objects
   3  */
   4
   5 #include <linux/module.h>
   6 #include <linux/init.h>
   7 #include <linux/kernel.h>
   8 #include <linux/acpi.h>
   9
  10 #include <acpi/acpi_drivers.h>
  11 #include <acpi/acinterp.h>      /* for acpi_ex_eisa_id_to_string() */
  12
  13 #define _COMPONENT              ACPI_BUS_COMPONENT
  14 ACPI_MODULE_NAME("scan")
  15 #define STRUCT_TO_INT(s)        (*((int*)&s))
  16 extern struct acpi_device *acpi_root;
  17
  18 #define ACPI_BUS_CLASS                  "system_bus"
  19 #define ACPI_BUS_HID                    "ACPI_BUS"
  20 #define ACPI_BUS_DRIVER_NAME            "ACPI Bus Driver"
  21 #define ACPI_BUS_DEVICE_NAME            "System Bus"
  22
  23 static LIST_HEAD(acpi_device_list);
  24 DEFINE_SPINLOCK(acpi_device_lock);
  25 LIST_HEAD(acpi_wakeup_device_list);
  26
  27
  28 static void acpi_device_release_legacy(struct kobject *kobj)
  29 {
  30         struct acpi_device *dev = container_of(kobj, struct acpi_device, kobj);
  31         kfree(dev->pnp.cid_list);
  32         kfree(dev);
  33 }
  34
  35 struct acpi_device_attribute {
  36         struct attribute attr;
  37          ssize_t(*show) (struct acpi_device *, char *);
  38          ssize_t(*store) (struct acpi_device *, const char *, size_t);
  39 };
  40
  41 typedef void acpi_device_sysfs_files(struct kobject *,
  42                                      const struct attribute *);
  43
  44 static void setup_sys_fs_device_files(struct acpi_device *dev,
  45                                       acpi_device_sysfs_files * func);
  46
  47 #define create_sysfs_device_files(dev)  \
  48         setup_sys_fs_device_files(dev, (acpi_device_sysfs_files *)&sysfs_create_file)
  49 #define remove_sysfs_device_files(dev)  \
  50         setup_sys_fs_device_files(dev, (acpi_device_sysfs_files *)&sysfs_remove_file)
  51
  52 #define to_acpi_dev(n) container_of(n, struct acpi_device, kobj)
  53 #define to_handle_attr(n) container_of(n, struct acpi_device_attribute, attr);
  54
  55 static ssize_t acpi_device_attr_show(struct kobject *kobj,
  56                                      struct attribute *attr, char *buf)
  57 {
  58         struct acpi_device *device = to_acpi_dev(kobj);
  59         struct acpi_device_attribute *attribute = to_handle_attr(attr);
  60         return attribute->show ? attribute->show(device, buf) : -EIO;
  61 }
  62 static ssize_t acpi_device_attr_store(struct kobject *kobj,
  63                                       struct attribute *attr, const char *buf,
  64                                       size_t len)
  65 {
  66         struct acpi_device *device = to_acpi_dev(kobj);
  67         struct acpi_device_attribute *attribute = to_handle_attr(attr);
  68         return attribute->store ? attribute->store(device, buf, len) : -EIO;
  69 }
  70
  71 static struct sysfs_ops acpi_device_sysfs_ops = {
  72         .show = acpi_device_attr_show,
  73         .store = acpi_device_attr_store,
  74 };
  75
  76 static struct kobj_type ktype_acpi_ns = {
  77         .sysfs_ops = &acpi_device_sysfs_ops,
  78         .release = acpi_device_release_legacy,
  79 };
  80
  81 static int namespace_uevent(struct kset *kset, struct kobject *kobj,
  82                              char **envp, int num_envp, char *buffer,
  83                              int buffer_size)
  84 {
  85         struct acpi_device *dev = to_acpi_dev(kobj);
  86         int i = 0;
  87         int len = 0;
  88
  89         if (!dev->driver)
  90                 return 0;
  91
  92         if (add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
  93                            "PHYSDEVDRIVER=%s", dev->driver->name))
  94                 return -ENOMEM;
  95
  96         envp[i] = NULL;
  97
  98         return 0;
  99 }
 100
 101 static struct kset_uevent_ops namespace_uevent_ops = {
 102         .uevent = &namespace_uevent,
 103 };
 104
 105 static struct kset acpi_namespace_kset = {
 106         .kobj = {
 107                  .name = "namespace",
 108                  },
 109         .subsys = &acpi_subsys,
 110         .ktype = &ktype_acpi_ns,
 111         .uevent_ops = &namespace_uevent_ops,
 112 };
 113
 114 /* --------------------------------------------------------------------------
 115                 ACPI sysfs device file support
 116    -------------------------------------------------------------------------- */
 117 static ssize_t acpi_eject_store(struct acpi_device *device,
 118                                 const char *buf, size_t count);
 119
 120 #define ACPI_DEVICE_ATTR(_name,_mode,_show,_store) \
 121 static struct acpi_device_attribute acpi_device_attr_##_name = \
 122                 __ATTR(_name, _mode, _show, _store)
 123
 124 ACPI_DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
 125
 126 /**
 127  * setup_sys_fs_device_files - sets up the device files under device namespace
 128  * @dev:        acpi_device object
 129  * @func:       function pointer to create or destroy the device file
 130  */
 131 static void
 132 setup_sys_fs_device_files(struct acpi_device *dev,
 133                           acpi_device_sysfs_files * func)
 134 {
 135         acpi_status status;
 136         acpi_handle temp = NULL;
 137
 138         /*
 139          * If device has _EJ0, 'eject' file is created that is used to trigger
 140          * hot-removal function from userland.
 141          */
 142         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 143         if (ACPI_SUCCESS(status))
 144                 (*(func)) (&dev->kobj, &acpi_device_attr_eject.attr);
 145 }
 146
 147 static int acpi_eject_operation(acpi_handle handle, int lockable)
 148 {
 149         struct acpi_object_list arg_list;
 150         union acpi_object arg;
 151         acpi_status status = AE_OK;
 152
 153         /*
 154          * TBD: evaluate _PS3?
 155          */
 156
 157         if (lockable) {
 158                 arg_list.count = 1;
 159                 arg_list.pointer = &arg;
 160                 arg.type = ACPI_TYPE_INTEGER;
 161                 arg.integer.value = 0;
 162                 acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
 163         }
 164
 165         arg_list.count = 1;
 166         arg_list.pointer = &arg;
 167         arg.type = ACPI_TYPE_INTEGER;
 168         arg.integer.value = 1;
 169
 170         /*
 171          * TBD: _EJD support.
 172          */
 173
 174         status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
 175         if (ACPI_FAILURE(status)) {
 176                 return (-ENODEV);
 177         }
 178
 179         return (0);
 180 }
 181
 182 static ssize_t
 183 acpi_eject_store(struct acpi_device *device, const char *buf, size_t count)
 184 {
 185         int result;
 186         int ret = count;
 187         int islockable;
 188         acpi_status status;
 189         acpi_handle handle;
 190         acpi_object_type type = 0;
 191
 192         if ((!count) || (buf[0] != '1')) {
 193                 return -EINVAL;
 194         }
 195 #ifndef FORCE_EJECT
 196         if (device->driver == NULL) {
 197                 ret = -ENODEV;
 198                 goto err;
 199         }
 200 #endif
 201         status = acpi_get_type(device->handle, &type);
 202         if (ACPI_FAILURE(status) || (!device->flags.ejectable)) {
 203                 ret = -ENODEV;
 204                 goto err;
 205         }
 206
 207         islockable = device->flags.lockable;
 208         handle = device->handle;
 209
 210         result = acpi_bus_trim(device, 1);
 211
 212         if (!result)
 213                 result = acpi_eject_operation(handle, islockable);
 214
 215         if (result) {
 216                 ret = -EBUSY;
 217         }
 218       err:
 219         return ret;
 220 }
 221
 222 /* --------------------------------------------------------------------------
 223                         ACPI Bus operations
 224    -------------------------------------------------------------------------- */
 225 static void acpi_device_release(struct device *dev)
 226 {
 227         struct acpi_device *acpi_dev = to_acpi_device(dev);
 228
 229         kfree(acpi_dev->pnp.cid_list);
 230         kfree(acpi_dev);
 231 }
 232
 233 static int acpi_device_suspend(struct device *dev, pm_message_t state)
 234 {
 235         struct acpi_device *acpi_dev = to_acpi_device(dev);
 236         struct acpi_driver *acpi_drv = acpi_dev->driver;
 237
 238         if (acpi_drv && acpi_drv->ops.suspend)
 239                 return acpi_drv->ops.suspend(acpi_dev, state);
 240         return 0;
 241 }
 242
 243 static int acpi_device_resume(struct device *dev)
 244 {
 245         struct acpi_device *acpi_dev = to_acpi_device(dev);
 246         struct acpi_driver *acpi_drv = acpi_dev->driver;
 247
 248         if (acpi_drv && acpi_drv->ops.resume)
 249                 return acpi_drv->ops.resume(acpi_dev);
 250         return 0;
 251 }
 252
 253 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
 254 {
 255         struct acpi_device *acpi_dev = to_acpi_device(dev);
 256         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
 257
 258         if (acpi_drv->ops.match)
 259                 return !acpi_drv->ops.match(acpi_dev, acpi_drv);
 260         return !acpi_match_ids(acpi_dev, acpi_drv->ids);
 261 }
 262
 263 static int acpi_device_uevent(struct device *dev, char **envp, int num_envp,
 264         char *buffer, int buffer_size)
 265 {
 266         struct acpi_device *acpi_dev = to_acpi_device(dev);
 267         int i = 0, length = 0, ret = 0;
 268
 269         if (acpi_dev->flags.hardware_id)
 270                 ret = add_uevent_var(envp, num_envp, &i,
 271                         buffer, buffer_size, &length,
 272                         "HWID=%s", acpi_dev->pnp.hardware_id);
 273         if (ret)
 274                 return -ENOMEM;
 275         if (acpi_dev->flags.compatible_ids) {
 276                 int j;
 277                 struct acpi_compatible_id_list *cid_list;
 278
 279                 cid_list = acpi_dev->pnp.cid_list;
 280
 281                 for (j = 0; j < cid_list->count; j++) {
 282                         ret = add_uevent_var(envp, num_envp, &i, buffer,
 283                                 buffer_size, &length, "COMPTID=%s",
 284                                 cid_list->id[j].value);
 285                         if (ret)
 286                                 return -ENOMEM;
 287                 }
 288         }
 289
 290         envp[i] = NULL;
 291         return 0;
 292 }
 293
 294 static int acpi_bus_driver_init(struct acpi_device *, struct acpi_driver *);
 295 static int acpi_start_single_object(struct acpi_device *);
 296 static int acpi_device_probe(struct device * dev)
 297 {
 298         struct acpi_device *acpi_dev = to_acpi_device(dev);
 299         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
 300         int ret;
 301
 302         ret = acpi_bus_driver_init(acpi_dev, acpi_drv);
 303         if (!ret) {
 304                 acpi_start_single_object(acpi_dev);
 305                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 306                         "Found driver [%s] for device [%s]\n",
 307                         acpi_drv->name, acpi_dev->pnp.bus_id));
 308                 get_device(dev);
 309         }
 310         return ret;
 311 }
 312
 313 static int acpi_device_remove(struct device * dev)
 314 {
 315         struct acpi_device *acpi_dev = to_acpi_device(dev);
 316         struct acpi_driver *acpi_drv = acpi_dev->driver;
 317
 318         if (acpi_drv) {
 319                 if (acpi_drv->ops.stop)
 320                         acpi_drv->ops.stop(acpi_dev, ACPI_BUS_REMOVAL_NORMAL);
 321                 if (acpi_drv->ops.remove)
 322                         acpi_drv->ops.remove(acpi_dev, ACPI_BUS_REMOVAL_NORMAL);
 323         }
 324         acpi_dev->driver = NULL;
 325         acpi_driver_data(dev) = NULL;
 326
 327         put_device(dev);
 328         return 0;
 329 }
 330
 331 static void acpi_device_shutdown(struct device *dev)
 332 {
 333         struct acpi_device *acpi_dev = to_acpi_device(dev);
 334         struct acpi_driver *acpi_drv = acpi_dev->driver;
 335
 336         if (acpi_drv && acpi_drv->ops.shutdown)
 337                 acpi_drv->ops.shutdown(acpi_dev);
 338
 339         return ;
 340 }
 341
 342 static struct bus_type acpi_bus_type = {
 343         .name           = "acpi",
 344         .suspend        = acpi_device_suspend,
 345         .resume         = acpi_device_resume,
 346         .shutdown       = acpi_device_shutdown,
 347         .match          = acpi_bus_match,
 348         .probe          = acpi_device_probe,
 349         .remove         = acpi_device_remove,
 350         .uevent         = acpi_device_uevent,
 351 };
 352
 353 static void acpi_device_register(struct acpi_device *device,
 354                                  struct acpi_device *parent)
 355 {
 356         int err;
 357
 358         /*
 359          * Linkage
 360          * -------
 361          * Link this device to its parent and siblings.
 362          */
 363         INIT_LIST_HEAD(&device->children);
 364         INIT_LIST_HEAD(&device->node);
 365         INIT_LIST_HEAD(&device->g_list);
 366         INIT_LIST_HEAD(&device->wakeup_list);
 367
 368         spin_lock(&acpi_device_lock);
 369         if (device->parent) {
 370                 list_add_tail(&device->node, &device->parent->children);
 371                 list_add_tail(&device->g_list, &device->parent->g_list);
 372         } else
 373                 list_add_tail(&device->g_list, &acpi_device_list);
 374         if (device->wakeup.flags.valid)
 375                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
 376         spin_unlock(&acpi_device_lock);
 377
 378         strlcpy(device->kobj.name, device->pnp.bus_id, KOBJ_NAME_LEN);
 379         if (parent)
 380                 device->kobj.parent = &parent->kobj;
 381         device->kobj.ktype = &ktype_acpi_ns;
 382         device->kobj.kset = &acpi_namespace_kset;
 383         err = kobject_register(&device->kobj);
 384         if (err < 0)
 385                 printk(KERN_WARNING "%s: kobject_register error: %d\n",
 386                         __FUNCTION__, err);
 387         create_sysfs_device_files(device);
 388
 389         if (device->parent)
 390                 device->dev.parent = &parent->dev;
 391         device->dev.bus = &acpi_bus_type;
 392         device_initialize(&device->dev);
 393         sprintf(device->dev.bus_id, "%s", device->pnp.bus_id);
 394         device->dev.release = &acpi_device_release;
 395         device_add(&device->dev);
 396 }
 397
 398 static void acpi_device_unregister(struct acpi_device *device, int type)
 399 {
 400         spin_lock(&acpi_device_lock);
 401         if (device->parent) {
 402                 list_del(&device->node);
 403                 list_del(&device->g_list);
 404         } else
 405                 list_del(&device->g_list);
 406
 407         list_del(&device->wakeup_list);
 408
 409         spin_unlock(&acpi_device_lock);
 410
 411         acpi_detach_data(device->handle, acpi_bus_data_handler);
 412         remove_sysfs_device_files(device);
 413         kobject_unregister(&device->kobj);
 414
 415         device_unregister(&device->dev);
 416 }
 417
 418 /* --------------------------------------------------------------------------
 419                                  Driver Management
 420    -------------------------------------------------------------------------- */
 421 /**
 422  * acpi_bus_driver_init - add a device to a driver
 423  * @device: the device to add and initialize
 424  * @driver: driver for the device
 425  *
 426  * Used to initialize a device via its device driver.  Called whenever a
 427  * driver is bound to a device.  Invokes the driver's add() ops.
 428  */
 429 static int
 430 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
 431 {
 432         int result = 0;
 433
 434
 435         if (!device || !driver)
 436                 return -EINVAL;
 437
 438         if (!driver->ops.add)
 439                 return -ENOSYS;
 440
 441         result = driver->ops.add(device);
 442         if (result) {
 443                 device->driver = NULL;
 444                 acpi_driver_data(device) = NULL;
 445                 return result;
 446         }
 447
 448         device->driver = driver;
 449
 450         /*
 451          * TBD - Configuration Management: Assign resources to device based
 452          * upon possible configuration and currently allocated resources.
 453          */
 454
 455         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 456                           "Driver successfully bound to device\n"));
 457         return 0;
 458 }
 459
 460 static int acpi_start_single_object(struct acpi_device *device)
 461 {
 462         int result = 0;
 463         struct acpi_driver *driver;
 464
 465
 466         if (!(driver = device->driver))
 467                 return 0;
 468
 469         if (driver->ops.start) {
 470                 result = driver->ops.start(device);
 471                 if (result && driver->ops.remove)
 472                         driver->ops.remove(device, ACPI_BUS_REMOVAL_NORMAL);
 473         }
 474
 475         return result;
 476 }
 477
 478 /**
 479  * acpi_bus_register_driver - register a driver with the ACPI bus
 480  * @driver: driver being registered
 481  *
 482  * Registers a driver with the ACPI bus.  Searches the namespace for all
 483  * devices that match the driver's criteria and binds.  Returns zero for
 484  * success or a negative error status for failure.
 485  */
 486 int acpi_bus_register_driver(struct acpi_driver *driver)
 487 {
 488         int ret;
 489
 490         if (acpi_disabled)
 491                 return -ENODEV;
 492         driver->drv.name = driver->name;
 493         driver->drv.bus = &acpi_bus_type;
 494         driver->drv.owner = driver->owner;
 495
 496         ret = driver_register(&driver->drv);
 497         return ret;
 498 }
 499
 500 EXPORT_SYMBOL(acpi_bus_register_driver);
 501
 502 /**
 503  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
 504  * @driver: driver to unregister
 505  *
 506  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
 507  * devices that match the driver's criteria and unbinds.
 508  */
 509 void acpi_bus_unregister_driver(struct acpi_driver *driver)
 510 {
 511         driver_unregister(&driver->drv);
 512 }
 513
 514 EXPORT_SYMBOL(acpi_bus_unregister_driver);
 515
 516 /* --------------------------------------------------------------------------
 517                                  Device Enumeration
 518    -------------------------------------------------------------------------- */
 519 acpi_status
 520 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
 521 {
 522         acpi_status status;
 523         acpi_handle tmp;
 524         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 525         union acpi_object *obj;
 526
 527         status = acpi_get_handle(handle, "_EJD", &tmp);
 528         if (ACPI_FAILURE(status))
 529                 return status;
 530
 531         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
 532         if (ACPI_SUCCESS(status)) {
 533                 obj = buffer.pointer;
 534                 status = acpi_get_handle(NULL, obj->string.pointer, ejd);
 535                 kfree(buffer.pointer);
 536         }
 537         return status;
 538 }
 539 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
 540
 541 void acpi_bus_data_handler(acpi_handle handle, u32 function, void *context)
 542 {
 543
 544         /* TBD */
 545
 546         return;
 547 }
 548
 549 int acpi_match_ids(struct acpi_device *device, char *ids)
 550 {
 551         if (device->flags.hardware_id)
 552                 if (strstr(ids, device->pnp.hardware_id))
 553                         return 0;
 554
 555         if (device->flags.compatible_ids) {
 556                 struct acpi_compatible_id_list *cid_list = device->pnp.cid_list;
 557                 int i;
 558
 559                 /* compare multiple _CID entries against driver ids */
 560                 for (i = 0; i < cid_list->count; i++) {
 561                         if (strstr(ids, cid_list->id[i].value))
 562                                 return 0;
 563                 }
 564         }
 565         return -ENOENT;
 566 }
 567
 568 static int acpi_bus_get_perf_flags(struct acpi_device *device)
 569 {
 570         device->performance.state = ACPI_STATE_UNKNOWN;
 571         return 0;
 572 }
 573
 574 static acpi_status
 575 acpi_bus_extract_wakeup_device_power_package(struct acpi_device *device,
 576                                              union acpi_object *package)
 577 {
 578         int i = 0;
 579         union acpi_object *element = NULL;
 580
 581         if (!device || !package || (package->package.count < 2))
 582                 return AE_BAD_PARAMETER;
 583
 584         element = &(package->package.elements[0]);
 585         if (!element)
 586                 return AE_BAD_PARAMETER;
 587         if (element->type == ACPI_TYPE_PACKAGE) {
 588                 if ((element->package.count < 2) ||
 589                     (element->package.elements[0].type !=
 590                      ACPI_TYPE_LOCAL_REFERENCE)
 591                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
 592                         return AE_BAD_DATA;
 593                 device->wakeup.gpe_device =
 594                     element->package.elements[0].reference.handle;
 595                 device->wakeup.gpe_number =
 596                     (u32) element->package.elements[1].integer.value;
 597         } else if (element->type == ACPI_TYPE_INTEGER) {
 598                 device->wakeup.gpe_number = element->integer.value;
 599         } else
 600                 return AE_BAD_DATA;
 601
 602         element = &(package->package.elements[1]);
 603         if (element->type != ACPI_TYPE_INTEGER) {
 604                 return AE_BAD_DATA;
 605         }
 606         device->wakeup.sleep_state = element->integer.value;
 607
 608         if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
 609                 return AE_NO_MEMORY;
 610         }
 611         device->wakeup.resources.count = package->package.count - 2;
 612         for (i = 0; i < device->wakeup.resources.count; i++) {
 613                 element = &(package->package.elements[i + 2]);
 614                 if (element->type != ACPI_TYPE_ANY) {
 615                         return AE_BAD_DATA;
 616                 }
 617
 618                 device->wakeup.resources.handles[i] = element->reference.handle;
 619         }
 620
 621         return AE_OK;
 622 }
 623
 624 static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
 625 {
 626         acpi_status status = 0;
 627         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 628         union acpi_object *package = NULL;
 629
 630
 631         /* _PRW */
 632         status = acpi_evaluate_object(device->handle, "_PRW", NULL, &buffer);
 633         if (ACPI_FAILURE(status)) {
 634                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
 635                 goto end;
 636         }
 637
 638         package = (union acpi_object *)buffer.pointer;
 639         status = acpi_bus_extract_wakeup_device_power_package(device, package);
 640         if (ACPI_FAILURE(status)) {
 641                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _PRW package"));
 642                 goto end;
 643         }
 644
 645         kfree(buffer.pointer);
 646
 647         device->wakeup.flags.valid = 1;
 648         /* Power button, Lid switch always enable wakeup */
 649         if (!acpi_match_ids(device, "PNP0C0D,PNP0C0C,PNP0C0E"))
 650                 device->wakeup.flags.run_wake = 1;
 651
 652       end:
 653         if (ACPI_FAILURE(status))
 654                 device->flags.wake_capable = 0;
 655         return 0;
 656 }
 657
 658 static int acpi_bus_get_power_flags(struct acpi_device *device)
 659 {
 660         acpi_status status = 0;
 661         acpi_handle handle = NULL;
 662         u32 i = 0;
 663
 664
 665         /*
 666          * Power Management Flags
 667          */
 668         status = acpi_get_handle(device->handle, "_PSC", &handle);
 669         if (ACPI_SUCCESS(status))
 670                 device->power.flags.explicit_get = 1;
 671         status = acpi_get_handle(device->handle, "_IRC", &handle);
 672         if (ACPI_SUCCESS(status))
 673                 device->power.flags.inrush_current = 1;
 674
 675         /*
 676          * Enumerate supported power management states
 677          */
 678         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
 679                 struct acpi_device_power_state *ps = &device->power.states[i];
 680                 char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
 681
 682                 /* Evaluate "_PRx" to se if power resources are referenced */
 683                 acpi_evaluate_reference(device->handle, object_name, NULL,
 684                                         &ps->resources);
 685                 if (ps->resources.count) {
 686                         device->power.flags.power_resources = 1;
 687                         ps->flags.valid = 1;
 688                 }
 689
 690                 /* Evaluate "_PSx" to see if we can do explicit sets */
 691                 object_name[2] = 'S';
 692                 status = acpi_get_handle(device->handle, object_name, &handle);
 693                 if (ACPI_SUCCESS(status)) {
 694                         ps->flags.explicit_set = 1;
 695                         ps->flags.valid = 1;
 696                 }
 697
 698                 /* State is valid if we have some power control */
 699                 if (ps->resources.count || ps->flags.explicit_set)
 700                         ps->flags.valid = 1;
 701
 702                 ps->power = -1; /* Unknown - driver assigned */
 703                 ps->latency = -1;       /* Unknown - driver assigned */
 704         }
 705
 706         /* Set defaults for D0 and D3 states (always valid) */
 707         device->power.states[ACPI_STATE_D0].flags.valid = 1;
 708         device->power.states[ACPI_STATE_D0].power = 100;
 709         device->power.states[ACPI_STATE_D3].flags.valid = 1;
 710         device->power.states[ACPI_STATE_D3].power = 0;
 711
 712         /* TBD: System wake support and resource requirements. */
 713
 714         device->power.state = ACPI_STATE_UNKNOWN;
 715
 716         return 0;
 717 }
 718
 719 static int acpi_bus_get_flags(struct acpi_device *device)
 720 {
 721         acpi_status status = AE_OK;
 722         acpi_handle temp = NULL;
 723
 724
 725         /* Presence of _STA indicates 'dynamic_status' */
 726         status = acpi_get_handle(device->handle, "_STA", &temp);
 727         if (ACPI_SUCCESS(status))
 728                 device->flags.dynamic_status = 1;
 729
 730         /* Presence of _CID indicates 'compatible_ids' */
 731         status = acpi_get_handle(device->handle, "_CID", &temp);
 732         if (ACPI_SUCCESS(status))
 733                 device->flags.compatible_ids = 1;
 734
 735         /* Presence of _RMV indicates 'removable' */
 736         status = acpi_get_handle(device->handle, "_RMV", &temp);
 737         if (ACPI_SUCCESS(status))
 738                 device->flags.removable = 1;
 739
 740         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
 741         status = acpi_get_handle(device->handle, "_EJD", &temp);
 742         if (ACPI_SUCCESS(status))
 743                 device->flags.ejectable = 1;
 744         else {
 745                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
 746                 if (ACPI_SUCCESS(status))
 747                         device->flags.ejectable = 1;
 748         }
 749
 750         /* Presence of _LCK indicates 'lockable' */
 751         status = acpi_get_handle(device->handle, "_LCK", &temp);
 752         if (ACPI_SUCCESS(status))
 753                 device->flags.lockable = 1;
 754
 755         /* Presence of _PS0|_PR0 indicates 'power manageable' */
 756         status = acpi_get_handle(device->handle, "_PS0", &temp);
 757         if (ACPI_FAILURE(status))
 758                 status = acpi_get_handle(device->handle, "_PR0", &temp);
 759         if (ACPI_SUCCESS(status))
 760                 device->flags.power_manageable = 1;
 761
 762         /* Presence of _PRW indicates wake capable */
 763         status = acpi_get_handle(device->handle, "_PRW", &temp);
 764         if (ACPI_SUCCESS(status))
 765                 device->flags.wake_capable = 1;
 766
 767         /* TBD: Peformance management */
 768
 769         return 0;
 770 }
 771
 772 static void acpi_device_get_busid(struct acpi_device *device,
 773                                   acpi_handle handle, int type)
 774 {
 775         char bus_id[5] = { '?', 0 };
 776         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
 777         int i = 0;
 778
 779         /*
 780          * Bus ID
 781          * ------
 782          * The device's Bus ID is simply the object name.
 783          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
 784          */
 785         switch (type) {
 786         case ACPI_BUS_TYPE_SYSTEM:
 787                 strcpy(device->pnp.bus_id, "ACPI");
 788                 break;
 789         case ACPI_BUS_TYPE_POWER_BUTTON:
 790                 strcpy(device->pnp.bus_id, "PWRF");
 791                 break;
 792         case ACPI_BUS_TYPE_SLEEP_BUTTON:
 793                 strcpy(device->pnp.bus_id, "SLPF");
 794                 break;
 795         default:
 796                 acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
 797                 /* Clean up trailing underscores (if any) */
 798                 for (i = 3; i > 1; i--) {
 799                         if (bus_id[i] == '_')
 800                                 bus_id[i] = '\0';
 801                         else
 802                                 break;
 803                 }
 804                 strcpy(device->pnp.bus_id, bus_id);
 805                 break;
 806         }
 807 }
 808
 809 static void acpi_device_set_id(struct acpi_device *device,
 810                                struct acpi_device *parent, acpi_handle handle,
 811                                int type)
 812 {
 813         struct acpi_device_info *info;
 814         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 815         char *hid = NULL;
 816         char *uid = NULL;
 817         struct acpi_compatible_id_list *cid_list = NULL;
 818         acpi_status status;
 819
 820         switch (type) {
 821         case ACPI_BUS_TYPE_DEVICE:
 822                 status = acpi_get_object_info(handle, &buffer);
 823                 if (ACPI_FAILURE(status)) {
 824                         printk("%s: Error reading device info\n", __FUNCTION__);
 825                         return;
 826                 }
 827
 828                 info = buffer.pointer;
 829                 if (info->valid & ACPI_VALID_HID)
 830                         hid = info->hardware_id.value;
 831                 if (info->valid & ACPI_VALID_UID)
 832                         uid = info->unique_id.value;
 833                 if (info->valid & ACPI_VALID_CID)
 834                         cid_list = &info->compatibility_id;
 835                 if (info->valid & ACPI_VALID_ADR) {
 836                         device->pnp.bus_address = info->address;
 837                         device->flags.bus_address = 1;
 838                 }
 839                 break;
 840         case ACPI_BUS_TYPE_POWER:
 841                 hid = ACPI_POWER_HID;
 842                 break;
 843         case ACPI_BUS_TYPE_PROCESSOR:
 844                 hid = ACPI_PROCESSOR_HID;
 845                 break;
 846         case ACPI_BUS_TYPE_SYSTEM:
 847                 hid = ACPI_SYSTEM_HID;
 848                 break;
 849         case ACPI_BUS_TYPE_THERMAL:
 850                 hid = ACPI_THERMAL_HID;
 851                 break;
 852         case ACPI_BUS_TYPE_POWER_BUTTON:
 853                 hid = ACPI_BUTTON_HID_POWERF;
 854                 break;
 855         case ACPI_BUS_TYPE_SLEEP_BUTTON:
 856                 hid = ACPI_BUTTON_HID_SLEEPF;
 857                 break;
 858         }
 859
 860         /*
 861          * \_SB
 862          * ----
 863          * Fix for the system root bus device -- the only root-level device.
 864          */
 865         if (((acpi_handle)parent == ACPI_ROOT_OBJECT) && (type == ACPI_BUS_TYPE_DEVICE)) {
 866                 hid = ACPI_BUS_HID;
 867                 strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
 868                 strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
 869         }
 870
 871         if (hid) {
 872                 strcpy(device->pnp.hardware_id, hid);
 873                 device->flags.hardware_id = 1;
 874         }
 875         if (uid) {
 876                 strcpy(device->pnp.unique_id, uid);
 877                 device->flags.unique_id = 1;
 878         }
 879         if (cid_list) {
 880                 device->pnp.cid_list = kmalloc(cid_list->size, GFP_KERNEL);
 881                 if (device->pnp.cid_list)
 882                         memcpy(device->pnp.cid_list, cid_list, cid_list->size);
 883                 else
 884                         printk(KERN_ERR "Memory allocation error\n");
 885         }
 886
 887         kfree(buffer.pointer);
 888 }
 889
 890 static int acpi_device_set_context(struct acpi_device *device, int type)
 891 {
 892         acpi_status status = AE_OK;
 893         int result = 0;
 894         /*
 895          * Context
 896          * -------
 897          * Attach this 'struct acpi_device' to the ACPI object.  This makes
 898          * resolutions from handle->device very efficient.  Note that we need
 899          * to be careful with fixed-feature devices as they all attach to the
 900          * root object.
 901          */
 902         if (type != ACPI_BUS_TYPE_POWER_BUTTON &&
 903             type != ACPI_BUS_TYPE_SLEEP_BUTTON) {
 904                 status = acpi_attach_data(device->handle,
 905                                           acpi_bus_data_handler, device);
 906
 907                 if (ACPI_FAILURE(status)) {
 908                         printk("Error attaching device data\n");
 909                         result = -ENODEV;
 910                 }
 911         }
 912         return result;
 913 }
 914
 915 static void acpi_device_get_debug_info(struct acpi_device *device,
 916                                        acpi_handle handle, int type)
 917 {
 918 #ifdef CONFIG_ACPI_DEBUG_OUTPUT
 919         char *type_string = NULL;
 920         char name[80] = { '?', '\0' };
 921         struct acpi_buffer buffer = { sizeof(name), name };
 922
 923         switch (type) {
 924         case ACPI_BUS_TYPE_DEVICE:
 925                 type_string = "Device";
 926                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
 927                 break;
 928         case ACPI_BUS_TYPE_POWER:
 929                 type_string = "Power Resource";
 930                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
 931                 break;
 932         case ACPI_BUS_TYPE_PROCESSOR:
 933                 type_string = "Processor";
 934                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
 935                 break;
 936         case ACPI_BUS_TYPE_SYSTEM:
 937                 type_string = "System";
 938                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
 939                 break;
 940         case ACPI_BUS_TYPE_THERMAL:
 941                 type_string = "Thermal Zone";
 942                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
 943                 break;
 944         case ACPI_BUS_TYPE_POWER_BUTTON:
 945                 type_string = "Power Button";
 946                 sprintf(name, "PWRB");
 947                 break;
 948         case ACPI_BUS_TYPE_SLEEP_BUTTON:
 949                 type_string = "Sleep Button";
 950                 sprintf(name, "SLPB");
 951                 break;
 952         }
 953
 954         printk(KERN_DEBUG "Found %s %s [%p]\n", type_string, name, handle);
 955 #endif                          /*CONFIG_ACPI_DEBUG_OUTPUT */
 956 }
 957
 958 static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
 959 {
 960         if (!dev)
 961                 return -EINVAL;
 962
 963         device_release_driver(&dev->dev);
 964
 965         if (!rmdevice)
 966                 return 0;
 967
 968         if (dev->flags.bus_address) {
 969                 if ((dev->parent) && (dev->parent->ops.unbind))
 970                         dev->parent->ops.unbind(dev);
 971         }
 972
 973         acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
 974
 975         return 0;
 976 }
 977
 978 static int
 979 acpi_add_single_object(struct acpi_device **child,
 980                        struct acpi_device *parent, acpi_handle handle, int type)
 981 {
 982         int result = 0;
 983         struct acpi_device *device = NULL;
 984
 985
 986         if (!child)
 987                 return -EINVAL;
 988
 989         device = kmalloc(sizeof(struct acpi_device), GFP_KERNEL);
 990         if (!device) {
 991                 printk(KERN_ERR PREFIX "Memory allocation error\n");
 992                 return -ENOMEM;
 993         }
 994         memset(device, 0, sizeof(struct acpi_device));
 995
 996         device->handle = handle;
 997         device->parent = parent;
 998
 999         acpi_device_get_busid(device, handle, type);
1000
1001         /*
1002          * Flags
1003          * -----
1004          * Get prior to calling acpi_bus_get_status() so we know whether
1005          * or not _STA is present.  Note that we only look for object
1006          * handles -- cannot evaluate objects until we know the device is
1007          * present and properly initialized.
1008          */
1009         result = acpi_bus_get_flags(device);
1010         if (result)
1011                 goto end;
1012
1013         /*
1014          * Status
1015          * ------
1016          * See if the device is present.  We always assume that non-Device
1017          * and non-Processor objects (e.g. thermal zones, power resources,
1018          * etc.) are present, functioning, etc. (at least when parent object
1019          * is present).  Note that _STA has a different meaning for some
1020          * objects (e.g. power resources) so we need to be careful how we use
1021          * it.
1022          */
1023         switch (type) {
1024         case ACPI_BUS_TYPE_PROCESSOR:
1025         case ACPI_BUS_TYPE_DEVICE:
1026                 result = acpi_bus_get_status(device);
1027                 if (ACPI_FAILURE(result) || !device->status.present) {
1028                         result = -ENOENT;
1029                         goto end;
1030                 }
1031                 break;
1032         default:
1033                 STRUCT_TO_INT(device->status) = 0x0F;
1034                 break;
1035         }
1036
1037         /*
1038          * Initialize Device
1039          * -----------------
1040          * TBD: Synch with Core's enumeration/initialization process.
1041          */
1042
1043         /*
1044          * Hardware ID, Unique ID, & Bus Address
1045          * -------------------------------------
1046          */
1047         acpi_device_set_id(device, parent, handle, type);
1048
1049         /*
1050          * Power Management
1051          * ----------------
1052          */
1053         if (device->flags.power_manageable) {
1054                 result = acpi_bus_get_power_flags(device);
1055                 if (result)
1056                         goto end;
1057         }
1058
1059         /*
1060          * Wakeup device management
1061          *-----------------------
1062          */
1063         if (device->flags.wake_capable) {
1064                 result = acpi_bus_get_wakeup_device_flags(device);
1065                 if (result)
1066                         goto end;
1067         }
1068
1069         /*
1070          * Performance Management
1071          * ----------------------
1072          */
1073         if (device->flags.performance_manageable) {
1074                 result = acpi_bus_get_perf_flags(device);
1075                 if (result)
1076                         goto end;
1077         }
1078
1079         if ((result = acpi_device_set_context(device, type)))
1080                 goto end;
1081
1082         acpi_device_get_debug_info(device, handle, type);
1083
1084         acpi_device_register(device, parent);
1085
1086         /*
1087          * Bind _ADR-Based Devices
1088          * -----------------------
1089          * If there's a a bus address (_ADR) then we utilize the parent's
1090          * 'bind' function (if exists) to bind the ACPI- and natively-
1091          * enumerated device representations.
1092          */
1093         if (device->flags.bus_address) {
1094                 if (device->parent && device->parent->ops.bind)
1095                         device->parent->ops.bind(device);
1096         }
1097
1098       end:
1099         if (!result)
1100                 *child = device;
1101         else {
1102                 kfree(device->pnp.cid_list);
1103                 kfree(device);
1104         }
1105
1106         return result;
1107 }
1108
1109 static int acpi_bus_scan(struct acpi_device *start, struct acpi_bus_ops *ops)
1110 {
1111         acpi_status status = AE_OK;
1112         struct acpi_device *parent = NULL;
1113         struct acpi_device *child = NULL;
1114         acpi_handle phandle = NULL;
1115         acpi_handle chandle = NULL;
1116         acpi_object_type type = 0;
1117         u32 level = 1;
1118
1119
1120         if (!start)
1121                 return -EINVAL;
1122
1123         parent = start;
1124         phandle = start->handle;
1125
1126         /*
1127          * Parse through the ACPI namespace, identify all 'devices', and
1128          * create a new 'struct acpi_device' for each.
1129          */
1130         while ((level > 0) && parent) {
1131
1132                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1133                                               chandle, &chandle);
1134
1135                 /*
1136                  * If this scope is exhausted then move our way back up.
1137                  */
1138                 if (ACPI_FAILURE(status)) {
1139                         level--;
1140                         chandle = phandle;
1141                         acpi_get_parent(phandle, &phandle);
1142                         if (parent->parent)
1143                                 parent = parent->parent;
1144                         continue;
1145                 }
1146
1147                 status = acpi_get_type(chandle, &type);
1148                 if (ACPI_FAILURE(status))
1149                         continue;
1150
1151                 /*
1152                  * If this is a scope object then parse it (depth-first).
1153                  */
1154                 if (type == ACPI_TYPE_LOCAL_SCOPE) {
1155                         level++;
1156                         phandle = chandle;
1157                         chandle = NULL;
1158                         continue;
1159                 }
1160
1161                 /*
1162                  * We're only interested in objects that we consider 'devices'.
1163                  */
1164                 switch (type) {
1165                 case ACPI_TYPE_DEVICE:
1166                         type = ACPI_BUS_TYPE_DEVICE;
1167                         break;
1168                 case ACPI_TYPE_PROCESSOR:
1169                         type = ACPI_BUS_TYPE_PROCESSOR;
1170                         break;
1171                 case ACPI_TYPE_THERMAL:
1172                         type = ACPI_BUS_TYPE_THERMAL;
1173                         break;
1174                 case ACPI_TYPE_POWER:
1175                         type = ACPI_BUS_TYPE_POWER;
1176                         break;
1177                 default:
1178                         continue;
1179                 }
1180
1181                 if (ops->acpi_op_add)
1182                         status = acpi_add_single_object(&child, parent,
1183                                                         chandle, type);
1184                 else
1185                         status = acpi_bus_get_device(chandle, &child);
1186
1187                 if (ACPI_FAILURE(status))
1188                         continue;
1189
1190                 if (ops->acpi_op_start) {
1191                         status = acpi_start_single_object(child);
1192                         if (ACPI_FAILURE(status))
1193                                 continue;
1194                 }
1195
1196                 /*
1197                  * If the device is present, enabled, and functioning then
1198                  * parse its scope (depth-first).  Note that we need to
1199                  * represent absent devices to facilitate PnP notifications
1200                  * -- but only the subtree head (not all of its children,
1201                  * which will be enumerated when the parent is inserted).
1202                  *
1203                  * TBD: Need notifications and other detection mechanisms
1204                  *      in place before we can fully implement this.
1205                  */
1206                 if (child->status.present) {
1207                         status = acpi_get_next_object(ACPI_TYPE_ANY, chandle,
1208                                                       NULL, NULL);
1209                         if (ACPI_SUCCESS(status)) {
1210                                 level++;
1211                                 phandle = chandle;
1212                                 chandle = NULL;
1213                                 parent = child;
1214                         }
1215                 }
1216         }
1217
1218         return 0;
1219 }
1220
1221 int
1222 acpi_bus_add(struct acpi_device **child,
1223              struct acpi_device *parent, acpi_handle handle, int type)
1224 {
1225         int result;
1226         struct acpi_bus_ops ops;
1227
1228
1229         result = acpi_add_single_object(child, parent, handle, type);
1230         if (!result) {
1231                 memset(&ops, 0, sizeof(ops));
1232                 ops.acpi_op_add = 1;
1233                 result = acpi_bus_scan(*child, &ops);
1234         }
1235         return result;
1236 }
1237
1238 EXPORT_SYMBOL(acpi_bus_add);
1239
1240 int acpi_bus_start(struct acpi_device *device)
1241 {
1242         int result;
1243         struct acpi_bus_ops ops;
1244
1245
1246         if (!device)
1247                 return -EINVAL;
1248
1249         result = acpi_start_single_object(device);
1250         if (!result) {
1251                 memset(&ops, 0, sizeof(ops));
1252                 ops.acpi_op_start = 1;
1253                 result = acpi_bus_scan(device, &ops);
1254         }
1255         return result;
1256 }
1257
1258 EXPORT_SYMBOL(acpi_bus_start);
1259
1260 int acpi_bus_trim(struct acpi_device *start, int rmdevice)
1261 {
1262         acpi_status status;
1263         struct acpi_device *parent, *child;
1264         acpi_handle phandle, chandle;
1265         acpi_object_type type;
1266         u32 level = 1;
1267         int err = 0;
1268
1269         parent = start;
1270         phandle = start->handle;
1271         child = chandle = NULL;
1272
1273         while ((level > 0) && parent && (!err)) {
1274                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1275                                               chandle, &chandle);
1276
1277                 /*
1278                  * If this scope is exhausted then move our way back up.
1279                  */
1280                 if (ACPI_FAILURE(status)) {
1281                         level--;
1282                         chandle = phandle;
1283                         acpi_get_parent(phandle, &phandle);
1284                         child = parent;
1285                         parent = parent->parent;
1286
1287                         if (level == 0)
1288                                 err = acpi_bus_remove(child, rmdevice);
1289                         else
1290                                 err = acpi_bus_remove(child, 1);
1291
1292                         continue;
1293                 }
1294
1295                 status = acpi_get_type(chandle, &type);
1296                 if (ACPI_FAILURE(status)) {
1297                         continue;
1298                 }
1299                 /*
1300                  * If there is a device corresponding to chandle then
1301                  * parse it (depth-first).
1302                  */
1303                 if (acpi_bus_get_device(chandle, &child) == 0) {
1304                         level++;
1305                         phandle = chandle;
1306                         chandle = NULL;
1307                         parent = child;
1308                 }
1309                 continue;
1310         }
1311         return err;
1312 }
1313 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1314
1315
1316 static int acpi_bus_scan_fixed(struct acpi_device *root)
1317 {
1318         int result = 0;
1319         struct acpi_device *device = NULL;
1320
1321
1322         if (!root)
1323                 return -ENODEV;
1324
1325         /*
1326          * Enumerate all fixed-feature devices.
1327          */
1328         if (acpi_fadt.pwr_button == 0) {
1329                 result = acpi_add_single_object(&device, acpi_root,
1330                                                 NULL,
1331                                                 ACPI_BUS_TYPE_POWER_BUTTON);
1332                 if (!result)
1333                         result = acpi_start_single_object(device);
1334         }
1335
1336         if (acpi_fadt.sleep_button == 0) {
1337                 result = acpi_add_single_object(&device, acpi_root,
1338                                                 NULL,
1339                                                 ACPI_BUS_TYPE_SLEEP_BUTTON);
1340                 if (!result)
1341                         result = acpi_start_single_object(device);
1342         }
1343
1344         return result;
1345 }
1346
1347 static int __init acpi_scan_init(void)
1348 {
1349         int result;
1350         struct acpi_bus_ops ops;
1351
1352
1353         if (acpi_disabled)
1354                 return 0;
1355
1356         result = kset_register(&acpi_namespace_kset);
1357         if (result < 0)
1358                 printk(KERN_ERR PREFIX "kset_register error: %d\n", result);
1359
1360         result = bus_register(&acpi_bus_type);
1361         if (result) {
1362                 /* We don't want to quit even if we failed to add suspend/resume */
1363                 printk(KERN_ERR PREFIX "Could not register bus type\n");
1364         }
1365
1366         /*
1367          * Create the root device in the bus's device tree
1368          */
1369         result = acpi_add_single_object(&acpi_root, NULL, ACPI_ROOT_OBJECT,
1370                                         ACPI_BUS_TYPE_SYSTEM);
1371         if (result)
1372                 goto Done;
1373
1374         result = acpi_start_single_object(acpi_root);
1375         if (result)
1376                 goto Done;
1377
1378         /*
1379          * Enumerate devices in the ACPI namespace.
1380          */
1381         result = acpi_bus_scan_fixed(acpi_root);
1382         if (!result) {
1383                 memset(&ops, 0, sizeof(ops));
1384                 ops.acpi_op_add = 1;
1385                 ops.acpi_op_start = 1;
1386                 result = acpi_bus_scan(acpi_root, &ops);
1387         }
1388
1389         if (result)
1390                 acpi_device_unregister(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
1391
1392       Done:
1393         return result;
1394 }
1395
1396 subsys_initcall(acpi_scan_init);