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