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/acpi.h>
   8
   9 #include <acpi/acpi_drivers.h>
  10 #include <acpi/acinterp.h>      /* for acpi_ex_eisa_id_to_string() */
  11
  12 #define _COMPONENT              ACPI_BUS_COMPONENT
  13 ACPI_MODULE_NAME("scan")
  14 #define STRUCT_TO_INT(s)        (*((int*)&s))
  15 extern struct acpi_device *acpi_root;
  16
  17 #define ACPI_BUS_CLASS                  "system_bus"
  18 #define ACPI_BUS_HID                    "ACPI_BUS"
  19 #define ACPI_BUS_DRIVER_NAME            "ACPI Bus Driver"
  20 #define ACPI_BUS_DEVICE_NAME            "System Bus"
  21
  22 static LIST_HEAD(acpi_device_list);
  23 DEFINE_SPINLOCK(acpi_device_lock);
  24 LIST_HEAD(acpi_wakeup_device_list);
  25
  26
  27 static void acpi_device_release(struct kobject *kobj)
  28 {
  29         struct acpi_device *dev = container_of(kobj, struct acpi_device, kobj);
  30         kfree(dev->pnp.cid_list);
  31         kfree(dev);
  32 }
  33
  34 struct acpi_device_attribute {
  35         struct attribute attr;
  36          ssize_t(*show) (struct acpi_device *, char *);
  37          ssize_t(*store) (struct acpi_device *, const char *, size_t);
  38 };
  39
  40 typedef void acpi_device_sysfs_files(struct kobject *,
  41                                      const struct attribute *);
  42
  43 static void setup_sys_fs_device_files(struct acpi_device *dev,
  44                                       acpi_device_sysfs_files * func);
  45
  46 #define create_sysfs_device_files(dev)  \
  47         setup_sys_fs_device_files(dev, (acpi_device_sysfs_files *)&sysfs_create_file)
  48 #define remove_sysfs_device_files(dev)  \
  49         setup_sys_fs_device_files(dev, (acpi_device_sysfs_files *)&sysfs_remove_file)
  50
  51 #define to_acpi_device(n) container_of(n, struct acpi_device, kobj)
  52 #define to_handle_attr(n) container_of(n, struct acpi_device_attribute, attr);
  53
  54 static ssize_t acpi_device_attr_show(struct kobject *kobj,
  55                                      struct attribute *attr, char *buf)
  56 {
  57         struct acpi_device *device = to_acpi_device(kobj);
  58         struct acpi_device_attribute *attribute = to_handle_attr(attr);
  59         return attribute->show ? attribute->show(device, buf) : -EIO;
  60 }
  61 static ssize_t acpi_device_attr_store(struct kobject *kobj,
  62                                       struct attribute *attr, const char *buf,
  63                                       size_t len)
  64 {
  65         struct acpi_device *device = to_acpi_device(kobj);
  66         struct acpi_device_attribute *attribute = to_handle_attr(attr);
  67         return attribute->store ? attribute->store(device, buf, len) : -EIO;
  68 }
  69
  70 static struct sysfs_ops acpi_device_sysfs_ops = {
  71         .show = acpi_device_attr_show,
  72         .store = acpi_device_attr_store,
  73 };
  74
  75 static struct kobj_type ktype_acpi_ns = {
  76         .sysfs_ops = &acpi_device_sysfs_ops,
  77         .release = acpi_device_release,
  78 };
  79
  80 static int namespace_uevent(struct kset *kset, struct kobject *kobj,
  81                              char **envp, int num_envp, char *buffer,
  82                              int buffer_size)
  83 {
  84         struct acpi_device *dev = to_acpi_device(kobj);
  85         int i = 0;
  86         int len = 0;
  87
  88         if (!dev->driver)
  89                 return 0;
  90
  91         if (add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
  92                            "PHYSDEVDRIVER=%s", dev->driver->name))
  93                 return -ENOMEM;
  94
  95         envp[i] = NULL;
  96
  97         return 0;
  98 }
  99
 100 static struct kset_uevent_ops namespace_uevent_ops = {
 101         .uevent = &namespace_uevent,
 102 };
 103
 104 static struct kset acpi_namespace_kset = {
 105         .kobj = {
 106                  .name = "namespace",
 107                  },
 108         .subsys = &acpi_subsys,
 109         .ktype = &ktype_acpi_ns,
 110         .uevent_ops = &namespace_uevent_ops,
 111 };
 112
 113 static void acpi_device_register(struct acpi_device *device,
 114                                  struct acpi_device *parent)
 115 {
 116         /*
 117          * Linkage
 118          * -------
 119          * Link this device to its parent and siblings.
 120          */
 121         INIT_LIST_HEAD(&device->children);
 122         INIT_LIST_HEAD(&device->node);
 123         INIT_LIST_HEAD(&device->g_list);
 124         INIT_LIST_HEAD(&device->wakeup_list);
 125
 126         spin_lock(&acpi_device_lock);
 127         if (device->parent) {
 128                 list_add_tail(&device->node, &device->parent->children);
 129                 list_add_tail(&device->g_list, &device->parent->g_list);
 130         } else
 131                 list_add_tail(&device->g_list, &acpi_device_list);
 132         if (device->wakeup.flags.valid)
 133                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
 134         spin_unlock(&acpi_device_lock);
 135
 136         strlcpy(device->kobj.name, device->pnp.bus_id, KOBJ_NAME_LEN);
 137         if (parent)
 138                 device->kobj.parent = &parent->kobj;
 139         device->kobj.ktype = &ktype_acpi_ns;
 140         device->kobj.kset = &acpi_namespace_kset;
 141         kobject_register(&device->kobj);
 142         create_sysfs_device_files(device);
 143 }
 144
 145 static void acpi_device_unregister(struct acpi_device *device, int type)
 146 {
 147         spin_lock(&acpi_device_lock);
 148         if (device->parent) {
 149                 list_del(&device->node);
 150                 list_del(&device->g_list);
 151         } else
 152                 list_del(&device->g_list);
 153
 154         list_del(&device->wakeup_list);
 155
 156         spin_unlock(&acpi_device_lock);
 157
 158         acpi_detach_data(device->handle, acpi_bus_data_handler);
 159         remove_sysfs_device_files(device);
 160         kobject_unregister(&device->kobj);
 161 }
 162
 163 void acpi_bus_data_handler(acpi_handle handle, u32 function, void *context)
 164 {
 165
 166         /* TBD */
 167
 168         return;
 169 }
 170
 171 static int acpi_bus_get_power_flags(struct acpi_device *device)
 172 {
 173         acpi_status status = 0;
 174         acpi_handle handle = NULL;
 175         u32 i = 0;
 176
 177
 178         /*
 179          * Power Management Flags
 180          */
 181         status = acpi_get_handle(device->handle, "_PSC", &handle);
 182         if (ACPI_SUCCESS(status))
 183                 device->power.flags.explicit_get = 1;
 184         status = acpi_get_handle(device->handle, "_IRC", &handle);
 185         if (ACPI_SUCCESS(status))
 186                 device->power.flags.inrush_current = 1;
 187
 188         /*
 189          * Enumerate supported power management states
 190          */
 191         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
 192                 struct acpi_device_power_state *ps = &device->power.states[i];
 193                 char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
 194
 195                 /* Evaluate "_PRx" to se if power resources are referenced */
 196                 acpi_evaluate_reference(device->handle, object_name, NULL,
 197                                         &ps->resources);
 198                 if (ps->resources.count) {
 199                         device->power.flags.power_resources = 1;
 200                         ps->flags.valid = 1;
 201                 }
 202
 203                 /* Evaluate "_PSx" to see if we can do explicit sets */
 204                 object_name[2] = 'S';
 205                 status = acpi_get_handle(device->handle, object_name, &handle);
 206                 if (ACPI_SUCCESS(status)) {
 207                         ps->flags.explicit_set = 1;
 208                         ps->flags.valid = 1;
 209                 }
 210
 211                 /* State is valid if we have some power control */
 212                 if (ps->resources.count || ps->flags.explicit_set)
 213                         ps->flags.valid = 1;
 214
 215                 ps->power = -1; /* Unknown - driver assigned */
 216                 ps->latency = -1;       /* Unknown - driver assigned */
 217         }
 218
 219         /* Set defaults for D0 and D3 states (always valid) */
 220         device->power.states[ACPI_STATE_D0].flags.valid = 1;
 221         device->power.states[ACPI_STATE_D0].power = 100;
 222         device->power.states[ACPI_STATE_D3].flags.valid = 1;
 223         device->power.states[ACPI_STATE_D3].power = 0;
 224
 225         /* TBD: System wake support and resource requirements. */
 226
 227         device->power.state = ACPI_STATE_UNKNOWN;
 228
 229         return 0;
 230 }
 231
 232 int acpi_match_ids(struct acpi_device *device, char *ids)
 233 {
 234         if (device->flags.hardware_id)
 235                 if (strstr(ids, device->pnp.hardware_id))
 236                         return 0;
 237
 238         if (device->flags.compatible_ids) {
 239                 struct acpi_compatible_id_list *cid_list = device->pnp.cid_list;
 240                 int i;
 241
 242                 /* compare multiple _CID entries against driver ids */
 243                 for (i = 0; i < cid_list->count; i++) {
 244                         if (strstr(ids, cid_list->id[i].value))
 245                                 return 0;
 246                 }
 247         }
 248         return -ENOENT;
 249 }
 250
 251 static acpi_status
 252 acpi_bus_extract_wakeup_device_power_package(struct acpi_device *device,
 253                                              union acpi_object *package)
 254 {
 255         int i = 0;
 256         union acpi_object *element = NULL;
 257
 258         if (!device || !package || (package->package.count < 2))
 259                 return AE_BAD_PARAMETER;
 260
 261         element = &(package->package.elements[0]);
 262         if (!element)
 263                 return AE_BAD_PARAMETER;
 264         if (element->type == ACPI_TYPE_PACKAGE) {
 265                 if ((element->package.count < 2) ||
 266                     (element->package.elements[0].type !=
 267                      ACPI_TYPE_LOCAL_REFERENCE)
 268                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
 269                         return AE_BAD_DATA;
 270                 device->wakeup.gpe_device =
 271                     element->package.elements[0].reference.handle;
 272                 device->wakeup.gpe_number =
 273                     (u32) element->package.elements[1].integer.value;
 274         } else if (element->type == ACPI_TYPE_INTEGER) {
 275                 device->wakeup.gpe_number = element->integer.value;
 276         } else
 277                 return AE_BAD_DATA;
 278
 279         element = &(package->package.elements[1]);
 280         if (element->type != ACPI_TYPE_INTEGER) {
 281                 return AE_BAD_DATA;
 282         }
 283         device->wakeup.sleep_state = element->integer.value;
 284
 285         if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
 286                 return AE_NO_MEMORY;
 287         }
 288         device->wakeup.resources.count = package->package.count - 2;
 289         for (i = 0; i < device->wakeup.resources.count; i++) {
 290                 element = &(package->package.elements[i + 2]);
 291                 if (element->type != ACPI_TYPE_ANY) {
 292                         return AE_BAD_DATA;
 293                 }
 294
 295                 device->wakeup.resources.handles[i] = element->reference.handle;
 296         }
 297
 298         return AE_OK;
 299 }
 300
 301 static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
 302 {
 303         acpi_status status = 0;
 304         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 305         union acpi_object *package = NULL;
 306
 307
 308         /* _PRW */
 309         status = acpi_evaluate_object(device->handle, "_PRW", NULL, &buffer);
 310         if (ACPI_FAILURE(status)) {
 311                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
 312                 goto end;
 313         }
 314
 315         package = (union acpi_object *)buffer.pointer;
 316         status = acpi_bus_extract_wakeup_device_power_package(device, package);
 317         if (ACPI_FAILURE(status)) {
 318                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _PRW package"));
 319                 goto end;
 320         }
 321
 322         kfree(buffer.pointer);
 323
 324         device->wakeup.flags.valid = 1;
 325         /* Power button, Lid switch always enable wakeup */
 326         if (!acpi_match_ids(device, "PNP0C0D,PNP0C0C,PNP0C0E"))
 327                 device->wakeup.flags.run_wake = 1;
 328
 329       end:
 330         if (ACPI_FAILURE(status))
 331                 device->flags.wake_capable = 0;
 332         return 0;
 333 }
 334
 335 /* --------------------------------------------------------------------------
 336                 ACPI sysfs device file support
 337    -------------------------------------------------------------------------- */
 338 static ssize_t acpi_eject_store(struct acpi_device *device,
 339                                 const char *buf, size_t count);
 340
 341 #define ACPI_DEVICE_ATTR(_name,_mode,_show,_store) \
 342 static struct acpi_device_attribute acpi_device_attr_##_name = \
 343                 __ATTR(_name, _mode, _show, _store)
 344
 345 ACPI_DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
 346
 347 /**
 348  * setup_sys_fs_device_files - sets up the device files under device namespace
 349  * @dev:        acpi_device object
 350  * @func:       function pointer to create or destroy the device file
 351  */
 352 static void
 353 setup_sys_fs_device_files(struct acpi_device *dev,
 354                           acpi_device_sysfs_files * func)
 355 {
 356         acpi_status status;
 357         acpi_handle temp = NULL;
 358
 359         /*
 360          * If device has _EJ0, 'eject' file is created that is used to trigger
 361          * hot-removal function from userland.
 362          */
 363         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 364         if (ACPI_SUCCESS(status))
 365                 (*(func)) (&dev->kobj, &acpi_device_attr_eject.attr);
 366 }
 367
 368 static int acpi_eject_operation(acpi_handle handle, int lockable)
 369 {
 370         struct acpi_object_list arg_list;
 371         union acpi_object arg;
 372         acpi_status status = AE_OK;
 373
 374         /*
 375          * TBD: evaluate _PS3?
 376          */
 377
 378         if (lockable) {
 379                 arg_list.count = 1;
 380                 arg_list.pointer = &arg;
 381                 arg.type = ACPI_TYPE_INTEGER;
 382                 arg.integer.value = 0;
 383                 acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
 384         }
 385
 386         arg_list.count = 1;
 387         arg_list.pointer = &arg;
 388         arg.type = ACPI_TYPE_INTEGER;
 389         arg.integer.value = 1;
 390
 391         /*
 392          * TBD: _EJD support.
 393          */
 394
 395         status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
 396         if (ACPI_FAILURE(status)) {
 397                 return (-ENODEV);
 398         }
 399
 400         return (0);
 401 }
 402
 403 static ssize_t
 404 acpi_eject_store(struct acpi_device *device, const char *buf, size_t count)
 405 {
 406         int result;
 407         int ret = count;
 408         int islockable;
 409         acpi_status status;
 410         acpi_handle handle;
 411         acpi_object_type type = 0;
 412
 413         if ((!count) || (buf[0] != '1')) {
 414                 return -EINVAL;
 415         }
 416 #ifndef FORCE_EJECT
 417         if (device->driver == NULL) {
 418                 ret = -ENODEV;
 419                 goto err;
 420         }
 421 #endif
 422         status = acpi_get_type(device->handle, &type);
 423         if (ACPI_FAILURE(status) || (!device->flags.ejectable)) {
 424                 ret = -ENODEV;
 425                 goto err;
 426         }
 427
 428         islockable = device->flags.lockable;
 429         handle = device->handle;
 430
 431         result = acpi_bus_trim(device, 1);
 432
 433         if (!result)
 434                 result = acpi_eject_operation(handle, islockable);
 435
 436         if (result) {
 437                 ret = -EBUSY;
 438         }
 439       err:
 440         return ret;
 441 }
 442
 443 /* --------------------------------------------------------------------------
 444                               Performance Management
 445    -------------------------------------------------------------------------- */
 446
 447 static int acpi_bus_get_perf_flags(struct acpi_device *device)
 448 {
 449         device->performance.state = ACPI_STATE_UNKNOWN;
 450         return 0;
 451 }
 452
 453 /* --------------------------------------------------------------------------
 454                                  Driver Management
 455    -------------------------------------------------------------------------- */
 456
 457 static LIST_HEAD(acpi_bus_drivers);
 458
 459 /**
 460  * acpi_bus_match - match device IDs to driver's supported IDs
 461  * @device: the device that we are trying to match to a driver
 462  * @driver: driver whose device id table is being checked
 463  *
 464  * Checks the device's hardware (_HID) or compatible (_CID) ids to see if it
 465  * matches the specified driver's criteria.
 466  */
 467 static int
 468 acpi_bus_match(struct acpi_device *device, struct acpi_driver *driver)
 469 {
 470         if (driver && driver->ops.match)
 471                 return driver->ops.match(device, driver);
 472         return acpi_match_ids(device, driver->ids);
 473 }
 474
 475 /**
 476  * acpi_bus_driver_init - add a device to a driver
 477  * @device: the device to add and initialize
 478  * @driver: driver for the device
 479  *
 480  * Used to initialize a device via its device driver.  Called whenever a
 481  * driver is bound to a device.  Invokes the driver's add() and start() ops.
 482  */
 483 static int
 484 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
 485 {
 486         int result = 0;
 487
 488
 489         if (!device || !driver)
 490                 return -EINVAL;
 491
 492         if (!driver->ops.add)
 493                 return -ENOSYS;
 494
 495         result = driver->ops.add(device);
 496         if (result) {
 497                 device->driver = NULL;
 498                 acpi_driver_data(device) = NULL;
 499                 return result;
 500         }
 501
 502         device->driver = driver;
 503
 504         /*
 505          * TBD - Configuration Management: Assign resources to device based
 506          * upon possible configuration and currently allocated resources.
 507          */
 508
 509         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 510                           "Driver successfully bound to device\n"));
 511         return 0;
 512 }
 513
 514 static int acpi_start_single_object(struct acpi_device *device)
 515 {
 516         int result = 0;
 517         struct acpi_driver *driver;
 518
 519
 520         if (!(driver = device->driver))
 521                 return 0;
 522
 523         if (driver->ops.start) {
 524                 result = driver->ops.start(device);
 525                 if (result && driver->ops.remove)
 526                         driver->ops.remove(device, ACPI_BUS_REMOVAL_NORMAL);
 527         }
 528
 529         return result;
 530 }
 531
 532 static void acpi_driver_attach(struct acpi_driver *drv)
 533 {
 534         struct list_head *node, *next;
 535
 536
 537         spin_lock(&acpi_device_lock);
 538         list_for_each_safe(node, next, &acpi_device_list) {
 539                 struct acpi_device *dev =
 540                     container_of(node, struct acpi_device, g_list);
 541
 542                 if (dev->driver || !dev->status.present)
 543                         continue;
 544                 spin_unlock(&acpi_device_lock);
 545
 546                 if (!acpi_bus_match(dev, drv)) {
 547                         if (!acpi_bus_driver_init(dev, drv)) {
 548                                 acpi_start_single_object(dev);
 549                                 atomic_inc(&drv->references);
 550                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 551                                                   "Found driver [%s] for device [%s]\n",
 552                                                   drv->name, dev->pnp.bus_id));
 553                         }
 554                 }
 555                 spin_lock(&acpi_device_lock);
 556         }
 557         spin_unlock(&acpi_device_lock);
 558 }
 559
 560 static void acpi_driver_detach(struct acpi_driver *drv)
 561 {
 562         struct list_head *node, *next;
 563
 564
 565         spin_lock(&acpi_device_lock);
 566         list_for_each_safe(node, next, &acpi_device_list) {
 567                 struct acpi_device *dev =
 568                     container_of(node, struct acpi_device, g_list);
 569
 570                 if (dev->driver == drv) {
 571                         spin_unlock(&acpi_device_lock);
 572                         if (drv->ops.remove)
 573                                 drv->ops.remove(dev, ACPI_BUS_REMOVAL_NORMAL);
 574                         spin_lock(&acpi_device_lock);
 575                         dev->driver = NULL;
 576                         dev->driver_data = NULL;
 577                         atomic_dec(&drv->references);
 578                 }
 579         }
 580         spin_unlock(&acpi_device_lock);
 581 }
 582
 583 /**
 584  * acpi_bus_register_driver - register a driver with the ACPI bus
 585  * @driver: driver being registered
 586  *
 587  * Registers a driver with the ACPI bus.  Searches the namespace for all
 588  * devices that match the driver's criteria and binds.  Returns zero for
 589  * success or a negative error status for failure.
 590  */
 591 int acpi_bus_register_driver(struct acpi_driver *driver)
 592 {
 593
 594         if (acpi_disabled)
 595                 return -ENODEV;
 596
 597         spin_lock(&acpi_device_lock);
 598         list_add_tail(&driver->node, &acpi_bus_drivers);
 599         spin_unlock(&acpi_device_lock);
 600         acpi_driver_attach(driver);
 601
 602         return 0;
 603 }
 604
 605 EXPORT_SYMBOL(acpi_bus_register_driver);
 606
 607 /**
 608  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
 609  * @driver: driver to unregister
 610  *
 611  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
 612  * devices that match the driver's criteria and unbinds.
 613  */
 614 void acpi_bus_unregister_driver(struct acpi_driver *driver)
 615 {
 616         acpi_driver_detach(driver);
 617
 618         if (!atomic_read(&driver->references)) {
 619                 spin_lock(&acpi_device_lock);
 620                 list_del_init(&driver->node);
 621                 spin_unlock(&acpi_device_lock);
 622         }
 623         return;
 624 }
 625
 626 EXPORT_SYMBOL(acpi_bus_unregister_driver);
 627
 628 /**
 629  * acpi_bus_find_driver - check if there is a driver installed for the device
 630  * @device: device that we are trying to find a supporting driver for
 631  *
 632  * Parses the list of registered drivers looking for a driver applicable for
 633  * the specified device.
 634  */
 635 static int acpi_bus_find_driver(struct acpi_device *device)
 636 {
 637         int result = 0;
 638         struct list_head *node, *next;
 639
 640
 641         spin_lock(&acpi_device_lock);
 642         list_for_each_safe(node, next, &acpi_bus_drivers) {
 643                 struct acpi_driver *driver =
 644                     container_of(node, struct acpi_driver, node);
 645
 646                 atomic_inc(&driver->references);
 647                 spin_unlock(&acpi_device_lock);
 648                 if (!acpi_bus_match(device, driver)) {
 649                         result = acpi_bus_driver_init(device, driver);
 650                         if (!result)
 651                                 goto Done;
 652                 }
 653                 atomic_dec(&driver->references);
 654                 spin_lock(&acpi_device_lock);
 655         }
 656         spin_unlock(&acpi_device_lock);
 657
 658       Done:
 659         return result;
 660 }
 661
 662 /* --------------------------------------------------------------------------
 663                                  Device Enumeration
 664    -------------------------------------------------------------------------- */
 665
 666 acpi_status
 667 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
 668 {
 669         acpi_status status;
 670         acpi_handle tmp;
 671         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 672         union acpi_object *obj;
 673
 674         status = acpi_get_handle(handle, "_EJD", &tmp);
 675         if (ACPI_FAILURE(status))
 676                 return status;
 677
 678         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
 679         if (ACPI_SUCCESS(status)) {
 680                 obj = buffer.pointer;
 681                 status = acpi_get_handle(NULL, obj->string.pointer, ejd);
 682                 kfree(buffer.pointer);
 683         }
 684         return status;
 685 }
 686 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
 687
 688
 689 static int acpi_bus_get_flags(struct acpi_device *device)
 690 {
 691         acpi_status status = AE_OK;
 692         acpi_handle temp = NULL;
 693
 694
 695         /* Presence of _STA indicates 'dynamic_status' */
 696         status = acpi_get_handle(device->handle, "_STA", &temp);
 697         if (ACPI_SUCCESS(status))
 698                 device->flags.dynamic_status = 1;
 699
 700         /* Presence of _CID indicates 'compatible_ids' */
 701         status = acpi_get_handle(device->handle, "_CID", &temp);
 702         if (ACPI_SUCCESS(status))
 703                 device->flags.compatible_ids = 1;
 704
 705         /* Presence of _RMV indicates 'removable' */
 706         status = acpi_get_handle(device->handle, "_RMV", &temp);
 707         if (ACPI_SUCCESS(status))
 708                 device->flags.removable = 1;
 709
 710         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
 711         status = acpi_get_handle(device->handle, "_EJD", &temp);
 712         if (ACPI_SUCCESS(status))
 713                 device->flags.ejectable = 1;
 714         else {
 715                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
 716                 if (ACPI_SUCCESS(status))
 717                         device->flags.ejectable = 1;
 718         }
 719
 720         /* Presence of _LCK indicates 'lockable' */
 721         status = acpi_get_handle(device->handle, "_LCK", &temp);
 722         if (ACPI_SUCCESS(status))
 723                 device->flags.lockable = 1;
 724
 725         /* Presence of _PS0|_PR0 indicates 'power manageable' */
 726         status = acpi_get_handle(device->handle, "_PS0", &temp);
 727         if (ACPI_FAILURE(status))
 728                 status = acpi_get_handle(device->handle, "_PR0", &temp);
 729         if (ACPI_SUCCESS(status))
 730                 device->flags.power_manageable = 1;
 731
 732         /* Presence of _PRW indicates wake capable */
 733         status = acpi_get_handle(device->handle, "_PRW", &temp);
 734         if (ACPI_SUCCESS(status))
 735                 device->flags.wake_capable = 1;
 736
 737         /* TBD: Peformance management */
 738
 739         return 0;
 740 }
 741
 742 static void acpi_device_get_busid(struct acpi_device *device,
 743                                   acpi_handle handle, int type)
 744 {
 745         char bus_id[5] = { '?', 0 };
 746         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
 747         int i = 0;
 748
 749         /*
 750          * Bus ID
 751          * ------
 752          * The device's Bus ID is simply the object name.
 753          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
 754          */
 755         switch (type) {
 756         case ACPI_BUS_TYPE_SYSTEM:
 757                 strcpy(device->pnp.bus_id, "ACPI");
 758                 break;
 759         case ACPI_BUS_TYPE_POWER_BUTTON:
 760                 strcpy(device->pnp.bus_id, "PWRF");
 761                 break;
 762         case ACPI_BUS_TYPE_SLEEP_BUTTON:
 763                 strcpy(device->pnp.bus_id, "SLPF");
 764                 break;
 765         default:
 766                 acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
 767                 /* Clean up trailing underscores (if any) */
 768                 for (i = 3; i > 1; i--) {
 769                         if (bus_id[i] == '_')
 770                                 bus_id[i] = '\0';
 771                         else
 772                                 break;
 773                 }
 774                 strcpy(device->pnp.bus_id, bus_id);
 775                 break;
 776         }
 777 }
 778
 779 static void acpi_device_set_id(struct acpi_device *device,
 780                                struct acpi_device *parent, acpi_handle handle,
 781                                int type)
 782 {
 783         struct acpi_device_info *info;
 784         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 785         char *hid = NULL;
 786         char *uid = NULL;
 787         struct acpi_compatible_id_list *cid_list = NULL;
 788         acpi_status status;
 789
 790         switch (type) {
 791         case ACPI_BUS_TYPE_DEVICE:
 792                 status = acpi_get_object_info(handle, &buffer);
 793                 if (ACPI_FAILURE(status)) {
 794                         printk("%s: Error reading device info\n", __FUNCTION__);
 795                         return;
 796                 }
 797
 798                 info = buffer.pointer;
 799                 if (info->valid & ACPI_VALID_HID)
 800                         hid = info->hardware_id.value;
 801                 if (info->valid & ACPI_VALID_UID)
 802                         uid = info->unique_id.value;
 803                 if (info->valid & ACPI_VALID_CID)
 804                         cid_list = &info->compatibility_id;
 805                 if (info->valid & ACPI_VALID_ADR) {
 806                         device->pnp.bus_address = info->address;
 807                         device->flags.bus_address = 1;
 808                 }
 809                 break;
 810         case ACPI_BUS_TYPE_POWER:
 811                 hid = ACPI_POWER_HID;
 812                 break;
 813         case ACPI_BUS_TYPE_PROCESSOR:
 814                 hid = ACPI_PROCESSOR_HID;
 815                 break;
 816         case ACPI_BUS_TYPE_SYSTEM:
 817                 hid = ACPI_SYSTEM_HID;
 818                 break;
 819         case ACPI_BUS_TYPE_THERMAL:
 820                 hid = ACPI_THERMAL_HID;
 821                 break;
 822         case ACPI_BUS_TYPE_POWER_BUTTON:
 823                 hid = ACPI_BUTTON_HID_POWERF;
 824                 break;
 825         case ACPI_BUS_TYPE_SLEEP_BUTTON:
 826                 hid = ACPI_BUTTON_HID_SLEEPF;
 827                 break;
 828         }
 829
 830         /*
 831          * \_SB
 832          * ----
 833          * Fix for the system root bus device -- the only root-level device.
 834          */
 835         if (((acpi_handle)parent == ACPI_ROOT_OBJECT) && (type == ACPI_BUS_TYPE_DEVICE)) {
 836                 hid = ACPI_BUS_HID;
 837                 strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
 838                 strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
 839         }
 840
 841         if (hid) {
 842                 strcpy(device->pnp.hardware_id, hid);
 843                 device->flags.hardware_id = 1;
 844         }
 845         if (uid) {
 846                 strcpy(device->pnp.unique_id, uid);
 847                 device->flags.unique_id = 1;
 848         }
 849         if (cid_list) {
 850                 device->pnp.cid_list = kmalloc(cid_list->size, GFP_KERNEL);
 851                 if (device->pnp.cid_list)
 852                         memcpy(device->pnp.cid_list, cid_list, cid_list->size);
 853                 else
 854                         printk(KERN_ERR "Memory allocation error\n");
 855         }
 856
 857         kfree(buffer.pointer);
 858 }
 859
 860 static int acpi_device_set_context(struct acpi_device *device, int type)
 861 {
 862         acpi_status status = AE_OK;
 863         int result = 0;
 864         /*
 865          * Context
 866          * -------
 867          * Attach this 'struct acpi_device' to the ACPI object.  This makes
 868          * resolutions from handle->device very efficient.  Note that we need
 869          * to be careful with fixed-feature devices as they all attach to the
 870          * root object.
 871          */
 872         if (type != ACPI_BUS_TYPE_POWER_BUTTON &&
 873             type != ACPI_BUS_TYPE_SLEEP_BUTTON) {
 874                 status = acpi_attach_data(device->handle,
 875                                           acpi_bus_data_handler, device);
 876
 877                 if (ACPI_FAILURE(status)) {
 878                         printk("Error attaching device data\n");
 879                         result = -ENODEV;
 880                 }
 881         }
 882         return result;
 883 }
 884
 885 static void acpi_device_get_debug_info(struct acpi_device *device,
 886                                        acpi_handle handle, int type)
 887 {
 888 #ifdef CONFIG_ACPI_DEBUG_OUTPUT
 889         char *type_string = NULL;
 890         char name[80] = { '?', '\0' };
 891         struct acpi_buffer buffer = { sizeof(name), name };
 892
 893         switch (type) {
 894         case ACPI_BUS_TYPE_DEVICE:
 895                 type_string = "Device";
 896                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
 897                 break;
 898         case ACPI_BUS_TYPE_POWER:
 899                 type_string = "Power Resource";
 900                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
 901                 break;
 902         case ACPI_BUS_TYPE_PROCESSOR:
 903                 type_string = "Processor";
 904                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
 905                 break;
 906         case ACPI_BUS_TYPE_SYSTEM:
 907                 type_string = "System";
 908                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
 909                 break;
 910         case ACPI_BUS_TYPE_THERMAL:
 911                 type_string = "Thermal Zone";
 912                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
 913                 break;
 914         case ACPI_BUS_TYPE_POWER_BUTTON:
 915                 type_string = "Power Button";
 916                 sprintf(name, "PWRB");
 917                 break;
 918         case ACPI_BUS_TYPE_SLEEP_BUTTON:
 919                 type_string = "Sleep Button";
 920                 sprintf(name, "SLPB");
 921                 break;
 922         }
 923
 924         printk(KERN_DEBUG "Found %s %s [%p]\n", type_string, name, handle);
 925 #endif                          /*CONFIG_ACPI_DEBUG_OUTPUT */
 926 }
 927
 928 static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
 929 {
 930         int result = 0;
 931         struct acpi_driver *driver;
 932
 933
 934         if (!dev)
 935                 return -EINVAL;
 936
 937         driver = dev->driver;
 938
 939         if ((driver) && (driver->ops.remove)) {
 940
 941                 if (driver->ops.stop) {
 942                         result = driver->ops.stop(dev, ACPI_BUS_REMOVAL_EJECT);
 943                         if (result)
 944                                 return result;
 945                 }
 946
 947                 result = dev->driver->ops.remove(dev, ACPI_BUS_REMOVAL_EJECT);
 948                 if (result) {
 949                         return result;
 950                 }
 951
 952                 atomic_dec(&dev->driver->references);
 953                 dev->driver = NULL;
 954                 acpi_driver_data(dev) = NULL;
 955         }
 956
 957         if (!rmdevice)
 958                 return 0;
 959
 960         if (dev->flags.bus_address) {
 961                 if ((dev->parent) && (dev->parent->ops.unbind))
 962                         dev->parent->ops.unbind(dev);
 963         }
 964
 965         acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
 966
 967         return 0;
 968 }
 969
 970 static int
 971 acpi_add_single_object(struct acpi_device **child,
 972                        struct acpi_device *parent, acpi_handle handle, int type)
 973 {
 974         int result = 0;
 975         struct acpi_device *device = NULL;
 976
 977
 978         if (!child)
 979                 return -EINVAL;
 980
 981         device = kmalloc(sizeof(struct acpi_device), GFP_KERNEL);
 982         if (!device) {
 983                 printk(KERN_ERR PREFIX "Memory allocation error\n");
 984                 return -ENOMEM;
 985         }
 986         memset(device, 0, sizeof(struct acpi_device));
 987
 988         device->handle = handle;
 989         device->parent = parent;
 990
 991         acpi_device_get_busid(device, handle, type);
 992
 993         /*
 994          * Flags
 995          * -----
 996          * Get prior to calling acpi_bus_get_status() so we know whether
 997          * or not _STA is present.  Note that we only look for object
 998          * handles -- cannot evaluate objects until we know the device is
 999          * present and properly initialized.
1000          */
1001         result = acpi_bus_get_flags(device);
1002         if (result)
1003                 goto end;
1004
1005         /*
1006          * Status
1007          * ------
1008          * See if the device is present.  We always assume that non-Device
1009          * and non-Processor objects (e.g. thermal zones, power resources,
1010          * etc.) are present, functioning, etc. (at least when parent object
1011          * is present).  Note that _STA has a different meaning for some
1012          * objects (e.g. power resources) so we need to be careful how we use
1013          * it.
1014          */
1015         switch (type) {
1016         case ACPI_BUS_TYPE_PROCESSOR:
1017         case ACPI_BUS_TYPE_DEVICE:
1018                 result = acpi_bus_get_status(device);
1019                 if (ACPI_FAILURE(result) || !device->status.present) {
1020                         result = -ENOENT;
1021                         goto end;
1022                 }
1023                 break;
1024         default:
1025                 STRUCT_TO_INT(device->status) = 0x0F;
1026                 break;
1027         }
1028
1029         /*
1030          * Initialize Device
1031          * -----------------
1032          * TBD: Synch with Core's enumeration/initialization process.
1033          */
1034
1035         /*
1036          * Hardware ID, Unique ID, & Bus Address
1037          * -------------------------------------
1038          */
1039         acpi_device_set_id(device, parent, handle, type);
1040
1041         /*
1042          * Power Management
1043          * ----------------
1044          */
1045         if (device->flags.power_manageable) {
1046                 result = acpi_bus_get_power_flags(device);
1047                 if (result)
1048                         goto end;
1049         }
1050
1051         /*
1052          * Wakeup device management
1053          *-----------------------
1054          */
1055         if (device->flags.wake_capable) {
1056                 result = acpi_bus_get_wakeup_device_flags(device);
1057                 if (result)
1058                         goto end;
1059         }
1060
1061         /*
1062          * Performance Management
1063          * ----------------------
1064          */
1065         if (device->flags.performance_manageable) {
1066                 result = acpi_bus_get_perf_flags(device);
1067                 if (result)
1068                         goto end;
1069         }
1070
1071         if ((result = acpi_device_set_context(device, type)))
1072                 goto end;
1073
1074         acpi_device_get_debug_info(device, handle, type);
1075
1076         acpi_device_register(device, parent);
1077
1078         /*
1079          * Bind _ADR-Based Devices
1080          * -----------------------
1081          * If there's a a bus address (_ADR) then we utilize the parent's
1082          * 'bind' function (if exists) to bind the ACPI- and natively-
1083          * enumerated device representations.
1084          */
1085         if (device->flags.bus_address) {
1086                 if (device->parent && device->parent->ops.bind)
1087                         device->parent->ops.bind(device);
1088         }
1089
1090         /*
1091          * Locate & Attach Driver
1092          * ----------------------
1093          * If there's a hardware id (_HID) or compatible ids (_CID) we check
1094          * to see if there's a driver installed for this kind of device.  Note
1095          * that drivers can install before or after a device is enumerated.
1096          *
1097          * TBD: Assumes LDM provides driver hot-plug capability.
1098          */
1099         acpi_bus_find_driver(device);
1100
1101       end:
1102         if (!result)
1103                 *child = device;
1104         else {
1105                 kfree(device->pnp.cid_list);
1106                 kfree(device);
1107         }
1108
1109         return result;
1110 }
1111
1112 static int acpi_bus_scan(struct acpi_device *start, struct acpi_bus_ops *ops)
1113 {
1114         acpi_status status = AE_OK;
1115         struct acpi_device *parent = NULL;
1116         struct acpi_device *child = NULL;
1117         acpi_handle phandle = NULL;
1118         acpi_handle chandle = NULL;
1119         acpi_object_type type = 0;
1120         u32 level = 1;
1121
1122
1123         if (!start)
1124                 return -EINVAL;
1125
1126         parent = start;
1127         phandle = start->handle;
1128
1129         /*
1130          * Parse through the ACPI namespace, identify all 'devices', and
1131          * create a new 'struct acpi_device' for each.
1132          */
1133         while ((level > 0) && parent) {
1134
1135                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1136                                               chandle, &chandle);
1137
1138                 /*
1139                  * If this scope is exhausted then move our way back up.
1140                  */
1141                 if (ACPI_FAILURE(status)) {
1142                         level--;
1143                         chandle = phandle;
1144                         acpi_get_parent(phandle, &phandle);
1145                         if (parent->parent)
1146                                 parent = parent->parent;
1147                         continue;
1148                 }
1149
1150                 status = acpi_get_type(chandle, &type);
1151                 if (ACPI_FAILURE(status))
1152                         continue;
1153
1154                 /*
1155                  * If this is a scope object then parse it (depth-first).
1156                  */
1157                 if (type == ACPI_TYPE_LOCAL_SCOPE) {
1158                         level++;
1159                         phandle = chandle;
1160                         chandle = NULL;
1161                         continue;
1162                 }
1163
1164                 /*
1165                  * We're only interested in objects that we consider 'devices'.
1166                  */
1167                 switch (type) {
1168                 case ACPI_TYPE_DEVICE:
1169                         type = ACPI_BUS_TYPE_DEVICE;
1170                         break;
1171                 case ACPI_TYPE_PROCESSOR:
1172                         type = ACPI_BUS_TYPE_PROCESSOR;
1173                         break;
1174                 case ACPI_TYPE_THERMAL:
1175                         type = ACPI_BUS_TYPE_THERMAL;
1176                         break;
1177                 case ACPI_TYPE_POWER:
1178                         type = ACPI_BUS_TYPE_POWER;
1179                         break;
1180                 default:
1181                         continue;
1182                 }
1183
1184                 if (ops->acpi_op_add)
1185                         status = acpi_add_single_object(&child, parent,
1186                                                         chandle, type);
1187                 else
1188                         status = acpi_bus_get_device(chandle, &child);
1189
1190                 if (ACPI_FAILURE(status))
1191                         continue;
1192
1193                 if (ops->acpi_op_start) {
1194                         status = acpi_start_single_object(child);
1195                         if (ACPI_FAILURE(status))
1196                                 continue;
1197                 }
1198
1199                 /*
1200                  * If the device is present, enabled, and functioning then
1201                  * parse its scope (depth-first).  Note that we need to
1202                  * represent absent devices to facilitate PnP notifications
1203                  * -- but only the subtree head (not all of its children,
1204                  * which will be enumerated when the parent is inserted).
1205                  *
1206                  * TBD: Need notifications and other detection mechanisms
1207                  *      in place before we can fully implement this.
1208                  */
1209                 if (child->status.present) {
1210                         status = acpi_get_next_object(ACPI_TYPE_ANY, chandle,
1211                                                       NULL, NULL);
1212                         if (ACPI_SUCCESS(status)) {
1213                                 level++;
1214                                 phandle = chandle;
1215                                 chandle = NULL;
1216                                 parent = child;
1217                         }
1218                 }
1219         }
1220
1221         return 0;
1222 }
1223
1224 int
1225 acpi_bus_add(struct acpi_device **child,
1226              struct acpi_device *parent, acpi_handle handle, int type)
1227 {
1228         int result;
1229         struct acpi_bus_ops ops;
1230
1231
1232         result = acpi_add_single_object(child, parent, handle, type);
1233         if (!result) {
1234                 memset(&ops, 0, sizeof(ops));
1235                 ops.acpi_op_add = 1;
1236                 result = acpi_bus_scan(*child, &ops);
1237         }
1238         return result;
1239 }
1240
1241 EXPORT_SYMBOL(acpi_bus_add);
1242
1243 int acpi_bus_start(struct acpi_device *device)
1244 {
1245         int result;
1246         struct acpi_bus_ops ops;
1247
1248
1249         if (!device)
1250                 return -EINVAL;
1251
1252         result = acpi_start_single_object(device);
1253         if (!result) {
1254                 memset(&ops, 0, sizeof(ops));
1255                 ops.acpi_op_start = 1;
1256                 result = acpi_bus_scan(device, &ops);
1257         }
1258         return result;
1259 }
1260
1261 EXPORT_SYMBOL(acpi_bus_start);
1262
1263 int acpi_bus_trim(struct acpi_device *start, int rmdevice)
1264 {
1265         acpi_status status;
1266         struct acpi_device *parent, *child;
1267         acpi_handle phandle, chandle;
1268         acpi_object_type type;
1269         u32 level = 1;
1270         int err = 0;
1271
1272         parent = start;
1273         phandle = start->handle;
1274         child = chandle = NULL;
1275
1276         while ((level > 0) && parent && (!err)) {
1277                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1278                                               chandle, &chandle);
1279
1280                 /*
1281                  * If this scope is exhausted then move our way back up.
1282                  */
1283                 if (ACPI_FAILURE(status)) {
1284                         level--;
1285                         chandle = phandle;
1286                         acpi_get_parent(phandle, &phandle);
1287                         child = parent;
1288                         parent = parent->parent;
1289
1290                         if (level == 0)
1291                                 err = acpi_bus_remove(child, rmdevice);
1292                         else
1293                                 err = acpi_bus_remove(child, 1);
1294
1295                         continue;
1296                 }
1297
1298                 status = acpi_get_type(chandle, &type);
1299                 if (ACPI_FAILURE(status)) {
1300                         continue;
1301                 }
1302                 /*
1303                  * If there is a device corresponding to chandle then
1304                  * parse it (depth-first).
1305                  */
1306                 if (acpi_bus_get_device(chandle, &child) == 0) {
1307                         level++;
1308                         phandle = chandle;
1309                         chandle = NULL;
1310                         parent = child;
1311                 }
1312                 continue;
1313         }
1314         return err;
1315 }
1316 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1317
1318
1319 static int acpi_bus_scan_fixed(struct acpi_device *root)
1320 {
1321         int result = 0;
1322         struct acpi_device *device = NULL;
1323
1324
1325         if (!root)
1326                 return -ENODEV;
1327
1328         /*
1329          * Enumerate all fixed-feature devices.
1330          */
1331         if (acpi_fadt.pwr_button == 0) {
1332                 result = acpi_add_single_object(&device, acpi_root,
1333                                                 NULL,
1334                                                 ACPI_BUS_TYPE_POWER_BUTTON);
1335                 if (!result)
1336                         result = acpi_start_single_object(device);
1337         }
1338
1339         if (acpi_fadt.sleep_button == 0) {
1340                 result = acpi_add_single_object(&device, acpi_root,
1341                                                 NULL,
1342                                                 ACPI_BUS_TYPE_SLEEP_BUTTON);
1343                 if (!result)
1344                         result = acpi_start_single_object(device);
1345         }
1346
1347         return result;
1348 }
1349
1350
1351 static inline struct acpi_device * to_acpi_dev(struct device * dev)
1352 {
1353         return container_of(dev, struct acpi_device, dev);
1354 }
1355
1356
1357 static int root_suspend(struct acpi_device * acpi_dev, pm_message_t state)
1358 {
1359         struct acpi_device * dev, * next;
1360         int result;
1361
1362         spin_lock(&acpi_device_lock);
1363         list_for_each_entry_safe_reverse(dev, next, &acpi_device_list, g_list) {
1364                 if (dev->driver && dev->driver->ops.suspend) {
1365                         spin_unlock(&acpi_device_lock);
1366                         result = dev->driver->ops.suspend(dev, 0);
1367                         if (result) {
1368                                 printk(KERN_ERR PREFIX "[%s - %s] Suspend failed: %d\n",
1369                                        acpi_device_name(dev),
1370                                        acpi_device_bid(dev), result);
1371                         }
1372                         spin_lock(&acpi_device_lock);
1373                 }
1374         }
1375         spin_unlock(&acpi_device_lock);
1376         return 0;
1377 }
1378
1379
1380 static int acpi_device_suspend(struct device * dev, pm_message_t state)
1381 {
1382         struct acpi_device * acpi_dev = to_acpi_dev(dev);
1383
1384         /*
1385          * For now, we should only register 1 generic device -
1386          * the ACPI root device - and from there, we walk the
1387          * tree of ACPI devices to suspend each one using the
1388          * ACPI driver methods.
1389          */
1390         if (acpi_dev->handle == ACPI_ROOT_OBJECT)
1391                 root_suspend(acpi_dev, state);
1392         return 0;
1393 }
1394
1395
1396
1397 static int root_resume(struct acpi_device * acpi_dev)
1398 {
1399         struct acpi_device * dev, * next;
1400         int result;
1401
1402         spin_lock(&acpi_device_lock);
1403         list_for_each_entry_safe(dev, next, &acpi_device_list, g_list) {
1404                 if (dev->driver && dev->driver->ops.resume) {
1405                         spin_unlock(&acpi_device_lock);
1406                         result = dev->driver->ops.resume(dev, 0);
1407                         if (result) {
1408                                 printk(KERN_ERR PREFIX "[%s - %s] resume failed: %d\n",
1409                                        acpi_device_name(dev),
1410                                        acpi_device_bid(dev), result);
1411                         }
1412                         spin_lock(&acpi_device_lock);
1413                 }
1414         }
1415         spin_unlock(&acpi_device_lock);
1416         return 0;
1417 }
1418
1419
1420 static int acpi_device_resume(struct device * dev)
1421 {
1422         struct acpi_device * acpi_dev = to_acpi_dev(dev);
1423
1424         /*
1425          * For now, we should only register 1 generic device -
1426          * the ACPI root device - and from there, we walk the
1427          * tree of ACPI devices to resume each one using the
1428          * ACPI driver methods.
1429          */
1430         if (acpi_dev->handle == ACPI_ROOT_OBJECT)
1431                 root_resume(acpi_dev);
1432         return 0;
1433 }
1434
1435
1436 static struct bus_type acpi_bus_type = {
1437         .name           = "acpi",
1438         .suspend        = acpi_device_suspend,
1439         .resume         = acpi_device_resume,
1440 };
1441
1442
1443
1444 static int __init acpi_scan_init(void)
1445 {
1446         int result;
1447         struct acpi_bus_ops ops;
1448
1449
1450         if (acpi_disabled)
1451                 return 0;
1452
1453         kset_register(&acpi_namespace_kset);
1454
1455         result = bus_register(&acpi_bus_type);
1456         if (result) {
1457                 /* We don't want to quit even if we failed to add suspend/resume */
1458                 printk(KERN_ERR PREFIX "Could not register bus type\n");
1459         }
1460
1461         /*
1462          * Create the root device in the bus's device tree
1463          */
1464         result = acpi_add_single_object(&acpi_root, NULL, ACPI_ROOT_OBJECT,
1465                                         ACPI_BUS_TYPE_SYSTEM);
1466         if (result)
1467                 goto Done;
1468
1469         result = acpi_start_single_object(acpi_root);
1470         if (result)
1471                 goto Done;
1472
1473         acpi_root->dev.bus = &acpi_bus_type;
1474         snprintf(acpi_root->dev.bus_id, BUS_ID_SIZE, "%s", acpi_bus_type.name);
1475         result = device_register(&acpi_root->dev);
1476         if (result) {
1477                 /* We don't want to quit even if we failed to add suspend/resume */
1478                 printk(KERN_ERR PREFIX "Could not register device\n");
1479         }
1480
1481         /*
1482          * Enumerate devices in the ACPI namespace.
1483          */
1484         result = acpi_bus_scan_fixed(acpi_root);
1485         if (!result) {
1486                 memset(&ops, 0, sizeof(ops));
1487                 ops.acpi_op_add = 1;
1488                 ops.acpi_op_start = 1;
1489                 result = acpi_bus_scan(acpi_root, &ops);
1490         }
1491
1492         if (result)
1493                 acpi_device_unregister(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
1494
1495       Done:
1496         return result;
1497 }
1498
1499 subsys_initcall(acpi_scan_init);