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 #include <linux/signal.h>
  10 #include <linux/kthread.h>
  11
  12 #include <acpi/acpi_drivers.h>
  13
  14 #include "internal.h"
  15
  16 #define _COMPONENT              ACPI_BUS_COMPONENT
  17 ACPI_MODULE_NAME("scan");
  18 #define STRUCT_TO_INT(s)        (*((int*)&s))
  19 extern struct acpi_device *acpi_root;
  20
  21 #define ACPI_BUS_CLASS                  "system_bus"
  22 #define ACPI_BUS_HID                    "LNXSYBUS"
  23 #define ACPI_BUS_DEVICE_NAME            "System Bus"
  24
  25 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
  26
  27 static LIST_HEAD(acpi_device_list);
  28 static LIST_HEAD(acpi_bus_id_list);
  29 DEFINE_MUTEX(acpi_device_lock);
  30 LIST_HEAD(acpi_wakeup_device_list);
  31
  32 struct acpi_device_bus_id{
  33         char bus_id[15];
  34         unsigned int instance_no;
  35         struct list_head node;
  36 };
  37
  38 /*
  39  * Creates hid/cid(s) string needed for modalias and uevent
  40  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
  41  * char *modalias: "acpi:IBM0001:ACPI0001"
  42 */
  43 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
  44                            int size)
  45 {
  46         int len;
  47         int count;
  48         struct acpi_hardware_id *id;
  49
  50         len = snprintf(modalias, size, "acpi:");
  51         size -= len;
  52
  53         list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
  54                 count = snprintf(&modalias[len], size, "%s:", id->id);
  55                 if (count < 0 || count >= size)
  56                         return -EINVAL;
  57                 len += count;
  58                 size -= count;
  59         }
  60
  61         modalias[len] = '\0';
  62         return len;
  63 }
  64
  65 static ssize_t
  66 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
  67         struct acpi_device *acpi_dev = to_acpi_device(dev);
  68         int len;
  69
  70         /* Device has no HID and no CID or string is >1024 */
  71         len = create_modalias(acpi_dev, buf, 1024);
  72         if (len <= 0)
  73                 return 0;
  74         buf[len++] = '\n';
  75         return len;
  76 }
  77 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
  78
  79 static void acpi_bus_hot_remove_device(void *context)
  80 {
  81         struct acpi_device *device;
  82         acpi_handle handle = context;
  83         struct acpi_object_list arg_list;
  84         union acpi_object arg;
  85         acpi_status status = AE_OK;
  86
  87         if (acpi_bus_get_device(handle, &device))
  88                 return;
  89
  90         if (!device)
  91                 return;
  92
  93         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
  94                 "Hot-removing device %s...\n", dev_name(&device->dev)));
  95
  96         if (acpi_bus_trim(device, 1)) {
  97                 printk(KERN_ERR PREFIX
  98                                 "Removing device failed\n");
  99                 return;
 100         }
 101
 102         /* power off device */
 103         status = acpi_evaluate_object(handle, "_PS3", NULL, NULL);
 104         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
 105                 printk(KERN_WARNING PREFIX
 106                                 "Power-off device failed\n");
 107
 108         if (device->flags.lockable) {
 109                 arg_list.count = 1;
 110                 arg_list.pointer = &arg;
 111                 arg.type = ACPI_TYPE_INTEGER;
 112                 arg.integer.value = 0;
 113                 acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
 114         }
 115
 116         arg_list.count = 1;
 117         arg_list.pointer = &arg;
 118         arg.type = ACPI_TYPE_INTEGER;
 119         arg.integer.value = 1;
 120
 121         /*
 122          * TBD: _EJD support.
 123          */
 124         status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
 125         if (ACPI_FAILURE(status))
 126                 printk(KERN_WARNING PREFIX
 127                                 "Eject device failed\n");
 128
 129         return;
 130 }
 131
 132 static ssize_t
 133 acpi_eject_store(struct device *d, struct device_attribute *attr,
 134                 const char *buf, size_t count)
 135 {
 136         int ret = count;
 137         acpi_status status;
 138         acpi_object_type type = 0;
 139         struct acpi_device *acpi_device = to_acpi_device(d);
 140
 141         if ((!count) || (buf[0] != '1')) {
 142                 return -EINVAL;
 143         }
 144 #ifndef FORCE_EJECT
 145         if (acpi_device->driver == NULL) {
 146                 ret = -ENODEV;
 147                 goto err;
 148         }
 149 #endif
 150         status = acpi_get_type(acpi_device->handle, &type);
 151         if (ACPI_FAILURE(status) || (!acpi_device->flags.ejectable)) {
 152                 ret = -ENODEV;
 153                 goto err;
 154         }
 155
 156         acpi_os_hotplug_execute(acpi_bus_hot_remove_device, acpi_device->handle);
 157 err:
 158         return ret;
 159 }
 160
 161 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
 162
 163 static ssize_t
 164 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
 165         struct acpi_device *acpi_dev = to_acpi_device(dev);
 166
 167         return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
 168 }
 169 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
 170
 171 static ssize_t
 172 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
 173         struct acpi_device *acpi_dev = to_acpi_device(dev);
 174         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
 175         int result;
 176
 177         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
 178         if (result)
 179                 goto end;
 180
 181         result = sprintf(buf, "%s\n", (char*)path.pointer);
 182         kfree(path.pointer);
 183 end:
 184         return result;
 185 }
 186 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
 187
 188 static int acpi_device_setup_files(struct acpi_device *dev)
 189 {
 190         acpi_status status;
 191         acpi_handle temp;
 192         int result = 0;
 193
 194         /*
 195          * Devices gotten from FADT don't have a "path" attribute
 196          */
 197         if (dev->handle) {
 198                 result = device_create_file(&dev->dev, &dev_attr_path);
 199                 if (result)
 200                         goto end;
 201         }
 202
 203         result = device_create_file(&dev->dev, &dev_attr_hid);
 204         if (result)
 205                 goto end;
 206
 207         result = device_create_file(&dev->dev, &dev_attr_modalias);
 208         if (result)
 209                 goto end;
 210
 211         /*
 212          * If device has _EJ0, 'eject' file is created that is used to trigger
 213          * hot-removal function from userland.
 214          */
 215         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 216         if (ACPI_SUCCESS(status))
 217                 result = device_create_file(&dev->dev, &dev_attr_eject);
 218 end:
 219         return result;
 220 }
 221
 222 static void acpi_device_remove_files(struct acpi_device *dev)
 223 {
 224         acpi_status status;
 225         acpi_handle temp;
 226
 227         /*
 228          * If device has _EJ0, 'eject' file is created that is used to trigger
 229          * hot-removal function from userland.
 230          */
 231         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 232         if (ACPI_SUCCESS(status))
 233                 device_remove_file(&dev->dev, &dev_attr_eject);
 234
 235         device_remove_file(&dev->dev, &dev_attr_modalias);
 236         device_remove_file(&dev->dev, &dev_attr_hid);
 237         if (dev->handle)
 238                 device_remove_file(&dev->dev, &dev_attr_path);
 239 }
 240 /* --------------------------------------------------------------------------
 241                         ACPI Bus operations
 242    -------------------------------------------------------------------------- */
 243
 244 int acpi_match_device_ids(struct acpi_device *device,
 245                           const struct acpi_device_id *ids)
 246 {
 247         const struct acpi_device_id *id;
 248         struct acpi_hardware_id *hwid;
 249
 250         /*
 251          * If the device is not present, it is unnecessary to load device
 252          * driver for it.
 253          */
 254         if (!device->status.present)
 255                 return -ENODEV;
 256
 257         for (id = ids; id->id[0]; id++)
 258                 list_for_each_entry(hwid, &device->pnp.ids, list)
 259                         if (!strcmp((char *) id->id, hwid->id))
 260                                 return 0;
 261
 262         return -ENOENT;
 263 }
 264 EXPORT_SYMBOL(acpi_match_device_ids);
 265
 266 static void acpi_free_ids(struct acpi_device *device)
 267 {
 268         struct acpi_hardware_id *id, *tmp;
 269
 270         list_for_each_entry_safe(id, tmp, &device->pnp.ids, list) {
 271                 kfree(id->id);
 272                 kfree(id);
 273         }
 274 }
 275
 276 static void acpi_device_release(struct device *dev)
 277 {
 278         struct acpi_device *acpi_dev = to_acpi_device(dev);
 279
 280         acpi_free_ids(acpi_dev);
 281         kfree(acpi_dev);
 282 }
 283
 284 static int acpi_device_suspend(struct device *dev, pm_message_t state)
 285 {
 286         struct acpi_device *acpi_dev = to_acpi_device(dev);
 287         struct acpi_driver *acpi_drv = acpi_dev->driver;
 288
 289         if (acpi_drv && acpi_drv->ops.suspend)
 290                 return acpi_drv->ops.suspend(acpi_dev, state);
 291         return 0;
 292 }
 293
 294 static int acpi_device_resume(struct device *dev)
 295 {
 296         struct acpi_device *acpi_dev = to_acpi_device(dev);
 297         struct acpi_driver *acpi_drv = acpi_dev->driver;
 298
 299         if (acpi_drv && acpi_drv->ops.resume)
 300                 return acpi_drv->ops.resume(acpi_dev);
 301         return 0;
 302 }
 303
 304 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
 305 {
 306         struct acpi_device *acpi_dev = to_acpi_device(dev);
 307         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
 308
 309         return !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
 310 }
 311
 312 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
 313 {
 314         struct acpi_device *acpi_dev = to_acpi_device(dev);
 315         int len;
 316
 317         if (add_uevent_var(env, "MODALIAS="))
 318                 return -ENOMEM;
 319         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
 320                               sizeof(env->buf) - env->buflen);
 321         if (len >= (sizeof(env->buf) - env->buflen))
 322                 return -ENOMEM;
 323         env->buflen += len;
 324         return 0;
 325 }
 326
 327 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
 328 {
 329         struct acpi_device *device = data;
 330
 331         device->driver->ops.notify(device, event);
 332 }
 333
 334 static acpi_status acpi_device_notify_fixed(void *data)
 335 {
 336         struct acpi_device *device = data;
 337
 338         /* Fixed hardware devices have no handles */
 339         acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
 340         return AE_OK;
 341 }
 342
 343 static int acpi_device_install_notify_handler(struct acpi_device *device)
 344 {
 345         acpi_status status;
 346
 347         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 348                 status =
 349                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 350                                                      acpi_device_notify_fixed,
 351                                                      device);
 352         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 353                 status =
 354                     acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 355                                                      acpi_device_notify_fixed,
 356                                                      device);
 357         else
 358                 status = acpi_install_notify_handler(device->handle,
 359                                                      ACPI_DEVICE_NOTIFY,
 360                                                      acpi_device_notify,
 361                                                      device);
 362
 363         if (ACPI_FAILURE(status))
 364                 return -EINVAL;
 365         return 0;
 366 }
 367
 368 static void acpi_device_remove_notify_handler(struct acpi_device *device)
 369 {
 370         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 371                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 372                                                 acpi_device_notify_fixed);
 373         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 374                 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 375                                                 acpi_device_notify_fixed);
 376         else
 377                 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
 378                                            acpi_device_notify);
 379 }
 380
 381 static int acpi_bus_driver_init(struct acpi_device *, struct acpi_driver *);
 382 static int acpi_start_single_object(struct acpi_device *);
 383 static int acpi_device_probe(struct device * dev)
 384 {
 385         struct acpi_device *acpi_dev = to_acpi_device(dev);
 386         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
 387         int ret;
 388
 389         ret = acpi_bus_driver_init(acpi_dev, acpi_drv);
 390         if (!ret) {
 391                 if (acpi_dev->bus_ops.acpi_op_start)
 392                         acpi_start_single_object(acpi_dev);
 393
 394                 if (acpi_drv->ops.notify) {
 395                         ret = acpi_device_install_notify_handler(acpi_dev);
 396                         if (ret) {
 397                                 if (acpi_drv->ops.remove)
 398                                         acpi_drv->ops.remove(acpi_dev,
 399                                                      acpi_dev->removal_type);
 400                                 return ret;
 401                         }
 402                 }
 403
 404                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 405                         "Found driver [%s] for device [%s]\n",
 406                         acpi_drv->name, acpi_dev->pnp.bus_id));
 407                 get_device(dev);
 408         }
 409         return ret;
 410 }
 411
 412 static int acpi_device_remove(struct device * dev)
 413 {
 414         struct acpi_device *acpi_dev = to_acpi_device(dev);
 415         struct acpi_driver *acpi_drv = acpi_dev->driver;
 416
 417         if (acpi_drv) {
 418                 if (acpi_drv->ops.notify)
 419                         acpi_device_remove_notify_handler(acpi_dev);
 420                 if (acpi_drv->ops.remove)
 421                         acpi_drv->ops.remove(acpi_dev, acpi_dev->removal_type);
 422         }
 423         acpi_dev->driver = NULL;
 424         acpi_dev->driver_data = NULL;
 425
 426         put_device(dev);
 427         return 0;
 428 }
 429
 430 static void acpi_device_shutdown(struct device *dev)
 431 {
 432         struct acpi_device *acpi_dev = to_acpi_device(dev);
 433         struct acpi_driver *acpi_drv = acpi_dev->driver;
 434
 435         if (acpi_drv && acpi_drv->ops.shutdown)
 436                 acpi_drv->ops.shutdown(acpi_dev);
 437
 438         return ;
 439 }
 440
 441 struct bus_type acpi_bus_type = {
 442         .name           = "acpi",
 443         .suspend        = acpi_device_suspend,
 444         .resume         = acpi_device_resume,
 445         .shutdown       = acpi_device_shutdown,
 446         .match          = acpi_bus_match,
 447         .probe          = acpi_device_probe,
 448         .remove         = acpi_device_remove,
 449         .uevent         = acpi_device_uevent,
 450 };
 451
 452 static int acpi_device_register(struct acpi_device *device)
 453 {
 454         int result;
 455         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
 456         int found = 0;
 457
 458         /*
 459          * Linkage
 460          * -------
 461          * Link this device to its parent and siblings.
 462          */
 463         INIT_LIST_HEAD(&device->children);
 464         INIT_LIST_HEAD(&device->node);
 465         INIT_LIST_HEAD(&device->wakeup_list);
 466
 467         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
 468         if (!new_bus_id) {
 469                 printk(KERN_ERR PREFIX "Memory allocation error\n");
 470                 return -ENOMEM;
 471         }
 472
 473         mutex_lock(&acpi_device_lock);
 474         /*
 475          * Find suitable bus_id and instance number in acpi_bus_id_list
 476          * If failed, create one and link it into acpi_bus_id_list
 477          */
 478         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
 479                 if (!strcmp(acpi_device_bus_id->bus_id,
 480                             acpi_device_hid(device))) {
 481                         acpi_device_bus_id->instance_no++;
 482                         found = 1;
 483                         kfree(new_bus_id);
 484                         break;
 485                 }
 486         }
 487         if (!found) {
 488                 acpi_device_bus_id = new_bus_id;
 489                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
 490                 acpi_device_bus_id->instance_no = 0;
 491                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
 492         }
 493         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
 494
 495         if (device->parent)
 496                 list_add_tail(&device->node, &device->parent->children);
 497
 498         if (device->wakeup.flags.valid)
 499                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
 500         mutex_unlock(&acpi_device_lock);
 501
 502         if (device->parent)
 503                 device->dev.parent = &device->parent->dev;
 504         device->dev.bus = &acpi_bus_type;
 505         device->dev.release = &acpi_device_release;
 506         result = device_register(&device->dev);
 507         if (result) {
 508                 dev_err(&device->dev, "Error registering device\n");
 509                 goto end;
 510         }
 511
 512         result = acpi_device_setup_files(device);
 513         if (result)
 514                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
 515                        dev_name(&device->dev));
 516
 517         device->removal_type = ACPI_BUS_REMOVAL_NORMAL;
 518         device_enable_async_suspend(&device->dev, true);
 519         return 0;
 520 end:
 521         mutex_lock(&acpi_device_lock);
 522         if (device->parent)
 523                 list_del(&device->node);
 524         list_del(&device->wakeup_list);
 525         mutex_unlock(&acpi_device_lock);
 526         return result;
 527 }
 528
 529 static void acpi_device_unregister(struct acpi_device *device, int type)
 530 {
 531         mutex_lock(&acpi_device_lock);
 532         if (device->parent)
 533                 list_del(&device->node);
 534
 535         list_del(&device->wakeup_list);
 536         mutex_unlock(&acpi_device_lock);
 537
 538         acpi_detach_data(device->handle, acpi_bus_data_handler);
 539
 540         acpi_device_remove_files(device);
 541         device_unregister(&device->dev);
 542 }
 543
 544 /* --------------------------------------------------------------------------
 545                                  Driver Management
 546    -------------------------------------------------------------------------- */
 547 /**
 548  * acpi_bus_driver_init - add a device to a driver
 549  * @device: the device to add and initialize
 550  * @driver: driver for the device
 551  *
 552  * Used to initialize a device via its device driver.  Called whenever a
 553  * driver is bound to a device.  Invokes the driver's add() ops.
 554  */
 555 static int
 556 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
 557 {
 558         int result = 0;
 559
 560         if (!device || !driver)
 561                 return -EINVAL;
 562
 563         if (!driver->ops.add)
 564                 return -ENOSYS;
 565
 566         result = driver->ops.add(device);
 567         if (result) {
 568                 device->driver = NULL;
 569                 device->driver_data = NULL;
 570                 return result;
 571         }
 572
 573         device->driver = driver;
 574
 575         /*
 576          * TBD - Configuration Management: Assign resources to device based
 577          * upon possible configuration and currently allocated resources.
 578          */
 579
 580         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 581                           "Driver successfully bound to device\n"));
 582         return 0;
 583 }
 584
 585 static int acpi_start_single_object(struct acpi_device *device)
 586 {
 587         int result = 0;
 588         struct acpi_driver *driver;
 589
 590
 591         if (!(driver = device->driver))
 592                 return 0;
 593
 594         if (driver->ops.start) {
 595                 result = driver->ops.start(device);
 596                 if (result && driver->ops.remove)
 597                         driver->ops.remove(device, ACPI_BUS_REMOVAL_NORMAL);
 598         }
 599
 600         return result;
 601 }
 602
 603 /**
 604  * acpi_bus_register_driver - register a driver with the ACPI bus
 605  * @driver: driver being registered
 606  *
 607  * Registers a driver with the ACPI bus.  Searches the namespace for all
 608  * devices that match the driver's criteria and binds.  Returns zero for
 609  * success or a negative error status for failure.
 610  */
 611 int acpi_bus_register_driver(struct acpi_driver *driver)
 612 {
 613         int ret;
 614
 615         if (acpi_disabled)
 616                 return -ENODEV;
 617         driver->drv.name = driver->name;
 618         driver->drv.bus = &acpi_bus_type;
 619         driver->drv.owner = driver->owner;
 620
 621         ret = driver_register(&driver->drv);
 622         return ret;
 623 }
 624
 625 EXPORT_SYMBOL(acpi_bus_register_driver);
 626
 627 /**
 628  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
 629  * @driver: driver to unregister
 630  *
 631  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
 632  * devices that match the driver's criteria and unbinds.
 633  */
 634 void acpi_bus_unregister_driver(struct acpi_driver *driver)
 635 {
 636         driver_unregister(&driver->drv);
 637 }
 638
 639 EXPORT_SYMBOL(acpi_bus_unregister_driver);
 640
 641 /* --------------------------------------------------------------------------
 642                                  Device Enumeration
 643    -------------------------------------------------------------------------- */
 644 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
 645 {
 646         acpi_status status;
 647         int ret;
 648         struct acpi_device *device;
 649
 650         /*
 651          * Fixed hardware devices do not appear in the namespace and do not
 652          * have handles, but we fabricate acpi_devices for them, so we have
 653          * to deal with them specially.
 654          */
 655         if (handle == NULL)
 656                 return acpi_root;
 657
 658         do {
 659                 status = acpi_get_parent(handle, &handle);
 660                 if (status == AE_NULL_ENTRY)
 661                         return NULL;
 662                 if (ACPI_FAILURE(status))
 663                         return acpi_root;
 664
 665                 ret = acpi_bus_get_device(handle, &device);
 666                 if (ret == 0)
 667                         return device;
 668         } while (1);
 669 }
 670
 671 acpi_status
 672 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
 673 {
 674         acpi_status status;
 675         acpi_handle tmp;
 676         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 677         union acpi_object *obj;
 678
 679         status = acpi_get_handle(handle, "_EJD", &tmp);
 680         if (ACPI_FAILURE(status))
 681                 return status;
 682
 683         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
 684         if (ACPI_SUCCESS(status)) {
 685                 obj = buffer.pointer;
 686                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
 687                                          ejd);
 688                 kfree(buffer.pointer);
 689         }
 690         return status;
 691 }
 692 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
 693
 694 void acpi_bus_data_handler(acpi_handle handle, void *context)
 695 {
 696
 697         /* TBD */
 698
 699         return;
 700 }
 701
 702 static int acpi_bus_get_perf_flags(struct acpi_device *device)
 703 {
 704         device->performance.state = ACPI_STATE_UNKNOWN;
 705         return 0;
 706 }
 707
 708 static acpi_status
 709 acpi_bus_extract_wakeup_device_power_package(struct acpi_device *device,
 710                                              union acpi_object *package)
 711 {
 712         int i = 0;
 713         union acpi_object *element = NULL;
 714
 715         if (!device || !package || (package->package.count < 2))
 716                 return AE_BAD_PARAMETER;
 717
 718         element = &(package->package.elements[0]);
 719         if (!element)
 720                 return AE_BAD_PARAMETER;
 721         if (element->type == ACPI_TYPE_PACKAGE) {
 722                 if ((element->package.count < 2) ||
 723                     (element->package.elements[0].type !=
 724                      ACPI_TYPE_LOCAL_REFERENCE)
 725                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
 726                         return AE_BAD_DATA;
 727                 device->wakeup.gpe_device =
 728                     element->package.elements[0].reference.handle;
 729                 device->wakeup.gpe_number =
 730                     (u32) element->package.elements[1].integer.value;
 731         } else if (element->type == ACPI_TYPE_INTEGER) {
 732                 device->wakeup.gpe_number = element->integer.value;
 733         } else
 734                 return AE_BAD_DATA;
 735
 736         element = &(package->package.elements[1]);
 737         if (element->type != ACPI_TYPE_INTEGER) {
 738                 return AE_BAD_DATA;
 739         }
 740         device->wakeup.sleep_state = element->integer.value;
 741
 742         if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
 743                 return AE_NO_MEMORY;
 744         }
 745         device->wakeup.resources.count = package->package.count - 2;
 746         for (i = 0; i < device->wakeup.resources.count; i++) {
 747                 element = &(package->package.elements[i + 2]);
 748                 if (element->type != ACPI_TYPE_LOCAL_REFERENCE)
 749                         return AE_BAD_DATA;
 750
 751                 device->wakeup.resources.handles[i] = element->reference.handle;
 752         }
 753
 754         return AE_OK;
 755 }
 756
 757 static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
 758 {
 759         acpi_status status = 0;
 760         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 761         union acpi_object *package = NULL;
 762         int psw_error;
 763
 764         struct acpi_device_id button_device_ids[] = {
 765                 {"PNP0C0D", 0},
 766                 {"PNP0C0C", 0},
 767                 {"PNP0C0E", 0},
 768                 {"", 0},
 769         };
 770
 771         /* _PRW */
 772         status = acpi_evaluate_object(device->handle, "_PRW", NULL, &buffer);
 773         if (ACPI_FAILURE(status)) {
 774                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
 775                 goto end;
 776         }
 777
 778         package = (union acpi_object *)buffer.pointer;
 779         status = acpi_bus_extract_wakeup_device_power_package(device, package);
 780         if (ACPI_FAILURE(status)) {
 781                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _PRW package"));
 782                 goto end;
 783         }
 784
 785         kfree(buffer.pointer);
 786
 787         device->wakeup.flags.valid = 1;
 788         device->wakeup.prepare_count = 0;
 789         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
 790          * system for the ACPI device with the _PRW object.
 791          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
 792          * So it is necessary to call _DSW object first. Only when it is not
 793          * present will the _PSW object used.
 794          */
 795         psw_error = acpi_device_sleep_wake(device, 0, 0, 0);
 796         if (psw_error)
 797                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 798                                 "error in _DSW or _PSW evaluation\n"));
 799
 800         /* Power button, Lid switch always enable wakeup */
 801         if (!acpi_match_device_ids(device, button_device_ids))
 802                 device->wakeup.flags.run_wake = 1;
 803
 804 end:
 805         if (ACPI_FAILURE(status))
 806                 device->flags.wake_capable = 0;
 807         return 0;
 808 }
 809
 810 static int acpi_bus_get_power_flags(struct acpi_device *device)
 811 {
 812         acpi_status status = 0;
 813         acpi_handle handle = NULL;
 814         u32 i = 0;
 815
 816
 817         /*
 818          * Power Management Flags
 819          */
 820         status = acpi_get_handle(device->handle, "_PSC", &handle);
 821         if (ACPI_SUCCESS(status))
 822                 device->power.flags.explicit_get = 1;
 823         status = acpi_get_handle(device->handle, "_IRC", &handle);
 824         if (ACPI_SUCCESS(status))
 825                 device->power.flags.inrush_current = 1;
 826
 827         /*
 828          * Enumerate supported power management states
 829          */
 830         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
 831                 struct acpi_device_power_state *ps = &device->power.states[i];
 832                 char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
 833
 834                 /* Evaluate "_PRx" to se if power resources are referenced */
 835                 acpi_evaluate_reference(device->handle, object_name, NULL,
 836                                         &ps->resources);
 837                 if (ps->resources.count) {
 838                         device->power.flags.power_resources = 1;
 839                         ps->flags.valid = 1;
 840                 }
 841
 842                 /* Evaluate "_PSx" to see if we can do explicit sets */
 843                 object_name[2] = 'S';
 844                 status = acpi_get_handle(device->handle, object_name, &handle);
 845                 if (ACPI_SUCCESS(status)) {
 846                         ps->flags.explicit_set = 1;
 847                         ps->flags.valid = 1;
 848                 }
 849
 850                 /* State is valid if we have some power control */
 851                 if (ps->resources.count || ps->flags.explicit_set)
 852                         ps->flags.valid = 1;
 853
 854                 ps->power = -1; /* Unknown - driver assigned */
 855                 ps->latency = -1;       /* Unknown - driver assigned */
 856         }
 857
 858         /* Set defaults for D0 and D3 states (always valid) */
 859         device->power.states[ACPI_STATE_D0].flags.valid = 1;
 860         device->power.states[ACPI_STATE_D0].power = 100;
 861         device->power.states[ACPI_STATE_D3].flags.valid = 1;
 862         device->power.states[ACPI_STATE_D3].power = 0;
 863
 864         /* TBD: System wake support and resource requirements. */
 865
 866         device->power.state = ACPI_STATE_UNKNOWN;
 867         acpi_bus_get_power(device->handle, &(device->power.state));
 868
 869         return 0;
 870 }
 871
 872 static int acpi_bus_get_flags(struct acpi_device *device)
 873 {
 874         acpi_status status = AE_OK;
 875         acpi_handle temp = NULL;
 876
 877
 878         /* Presence of _STA indicates 'dynamic_status' */
 879         status = acpi_get_handle(device->handle, "_STA", &temp);
 880         if (ACPI_SUCCESS(status))
 881                 device->flags.dynamic_status = 1;
 882
 883         /* Presence of _RMV indicates 'removable' */
 884         status = acpi_get_handle(device->handle, "_RMV", &temp);
 885         if (ACPI_SUCCESS(status))
 886                 device->flags.removable = 1;
 887
 888         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
 889         status = acpi_get_handle(device->handle, "_EJD", &temp);
 890         if (ACPI_SUCCESS(status))
 891                 device->flags.ejectable = 1;
 892         else {
 893                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
 894                 if (ACPI_SUCCESS(status))
 895                         device->flags.ejectable = 1;
 896         }
 897
 898         /* Presence of _LCK indicates 'lockable' */
 899         status = acpi_get_handle(device->handle, "_LCK", &temp);
 900         if (ACPI_SUCCESS(status))
 901                 device->flags.lockable = 1;
 902
 903         /* Presence of _PS0|_PR0 indicates 'power manageable' */
 904         status = acpi_get_handle(device->handle, "_PS0", &temp);
 905         if (ACPI_FAILURE(status))
 906                 status = acpi_get_handle(device->handle, "_PR0", &temp);
 907         if (ACPI_SUCCESS(status))
 908                 device->flags.power_manageable = 1;
 909
 910         /* Presence of _PRW indicates wake capable */
 911         status = acpi_get_handle(device->handle, "_PRW", &temp);
 912         if (ACPI_SUCCESS(status))
 913                 device->flags.wake_capable = 1;
 914
 915         /* TBD: Performance management */
 916
 917         return 0;
 918 }
 919
 920 static void acpi_device_get_busid(struct acpi_device *device)
 921 {
 922         char bus_id[5] = { '?', 0 };
 923         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
 924         int i = 0;
 925
 926         /*
 927          * Bus ID
 928          * ------
 929          * The device's Bus ID is simply the object name.
 930          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
 931          */
 932         if (ACPI_IS_ROOT_DEVICE(device)) {
 933                 strcpy(device->pnp.bus_id, "ACPI");
 934                 return;
 935         }
 936
 937         switch (device->device_type) {
 938         case ACPI_BUS_TYPE_POWER_BUTTON:
 939                 strcpy(device->pnp.bus_id, "PWRF");
 940                 break;
 941         case ACPI_BUS_TYPE_SLEEP_BUTTON:
 942                 strcpy(device->pnp.bus_id, "SLPF");
 943                 break;
 944         default:
 945                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
 946                 /* Clean up trailing underscores (if any) */
 947                 for (i = 3; i > 1; i--) {
 948                         if (bus_id[i] == '_')
 949                                 bus_id[i] = '\0';
 950                         else
 951                                 break;
 952                 }
 953                 strcpy(device->pnp.bus_id, bus_id);
 954                 break;
 955         }
 956 }
 957
 958 /*
 959  * acpi_bay_match - see if a device is an ejectable driver bay
 960  *
 961  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
 962  * then we can safely call it an ejectable drive bay
 963  */
 964 static int acpi_bay_match(struct acpi_device *device){
 965         acpi_status status;
 966         acpi_handle handle;
 967         acpi_handle tmp;
 968         acpi_handle phandle;
 969
 970         handle = device->handle;
 971
 972         status = acpi_get_handle(handle, "_EJ0", &tmp);
 973         if (ACPI_FAILURE(status))
 974                 return -ENODEV;
 975
 976         if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
 977                 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
 978                 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
 979                 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
 980                 return 0;
 981
 982         if (acpi_get_parent(handle, &phandle))
 983                 return -ENODEV;
 984
 985         if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
 986                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
 987                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
 988                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
 989                 return 0;
 990
 991         return -ENODEV;
 992 }
 993
 994 /*
 995  * acpi_dock_match - see if a device has a _DCK method
 996  */
 997 static int acpi_dock_match(struct acpi_device *device)
 998 {
 999         acpi_handle tmp;
1000         return acpi_get_handle(device->handle, "_DCK", &tmp);
1001 }
1002
1003 char *acpi_device_hid(struct acpi_device *device)
1004 {
1005         struct acpi_hardware_id *hid;
1006
1007         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1008         return hid->id;
1009 }
1010 EXPORT_SYMBOL(acpi_device_hid);
1011
1012 static void acpi_add_id(struct acpi_device *device, const char *dev_id)
1013 {
1014         struct acpi_hardware_id *id;
1015
1016         id = kmalloc(sizeof(*id), GFP_KERNEL);
1017         if (!id)
1018                 return;
1019
1020         id->id = kmalloc(strlen(dev_id) + 1, GFP_KERNEL);
1021         if (!id->id) {
1022                 kfree(id);
1023                 return;
1024         }
1025
1026         strcpy(id->id, dev_id);
1027         list_add_tail(&id->list, &device->pnp.ids);
1028 }
1029
1030 static void acpi_device_set_id(struct acpi_device *device)
1031 {
1032         acpi_status status;
1033         struct acpi_device_info *info;
1034         struct acpica_device_id_list *cid_list;
1035         int i;
1036
1037         switch (device->device_type) {
1038         case ACPI_BUS_TYPE_DEVICE:
1039                 if (ACPI_IS_ROOT_DEVICE(device)) {
1040                         acpi_add_id(device, ACPI_SYSTEM_HID);
1041                         break;
1042                 } else if (ACPI_IS_ROOT_DEVICE(device->parent)) {
1043                         /* \_SB_, the only root-level namespace device */
1044                         acpi_add_id(device, ACPI_BUS_HID);
1045                         strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
1046                         strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
1047                         break;
1048                 }
1049
1050                 status = acpi_get_object_info(device->handle, &info);
1051                 if (ACPI_FAILURE(status)) {
1052                         printk(KERN_ERR PREFIX "%s: Error reading device info\n", __func__);
1053                         return;
1054                 }
1055
1056                 if (info->valid & ACPI_VALID_HID)
1057                         acpi_add_id(device, info->hardware_id.string);
1058                 if (info->valid & ACPI_VALID_CID) {
1059                         cid_list = &info->compatible_id_list;
1060                         for (i = 0; i < cid_list->count; i++)
1061                                 acpi_add_id(device, cid_list->ids[i].string);
1062                 }
1063                 if (info->valid & ACPI_VALID_ADR) {
1064                         device->pnp.bus_address = info->address;
1065                         device->flags.bus_address = 1;
1066                 }
1067
1068                 kfree(info);
1069
1070                 /*
1071                  * Some devices don't reliably have _HIDs & _CIDs, so add
1072                  * synthetic HIDs to make sure drivers can find them.
1073                  */
1074                 if (acpi_is_video_device(device))
1075                         acpi_add_id(device, ACPI_VIDEO_HID);
1076                 else if (ACPI_SUCCESS(acpi_bay_match(device)))
1077                         acpi_add_id(device, ACPI_BAY_HID);
1078                 else if (ACPI_SUCCESS(acpi_dock_match(device)))
1079                         acpi_add_id(device, ACPI_DOCK_HID);
1080
1081                 break;
1082         case ACPI_BUS_TYPE_POWER:
1083                 acpi_add_id(device, ACPI_POWER_HID);
1084                 break;
1085         case ACPI_BUS_TYPE_PROCESSOR:
1086                 acpi_add_id(device, ACPI_PROCESSOR_OBJECT_HID);
1087                 break;
1088         case ACPI_BUS_TYPE_THERMAL:
1089                 acpi_add_id(device, ACPI_THERMAL_HID);
1090                 break;
1091         case ACPI_BUS_TYPE_POWER_BUTTON:
1092                 acpi_add_id(device, ACPI_BUTTON_HID_POWERF);
1093                 break;
1094         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1095                 acpi_add_id(device, ACPI_BUTTON_HID_SLEEPF);
1096                 break;
1097         }
1098
1099         /*
1100          * We build acpi_devices for some objects that don't have _HID or _CID,
1101          * e.g., PCI bridges and slots.  Drivers can't bind to these objects,
1102          * but we do use them indirectly by traversing the acpi_device tree.
1103          * This generic ID isn't useful for driver binding, but it provides
1104          * the useful property that "every acpi_device has an ID."
1105          */
1106         if (list_empty(&device->pnp.ids))
1107                 acpi_add_id(device, "device");
1108 }
1109
1110 static int acpi_device_set_context(struct acpi_device *device)
1111 {
1112         acpi_status status;
1113
1114         /*
1115          * Context
1116          * -------
1117          * Attach this 'struct acpi_device' to the ACPI object.  This makes
1118          * resolutions from handle->device very efficient.  Fixed hardware
1119          * devices have no handles, so we skip them.
1120          */
1121         if (!device->handle)
1122                 return 0;
1123
1124         status = acpi_attach_data(device->handle,
1125                                   acpi_bus_data_handler, device);
1126         if (ACPI_SUCCESS(status))
1127                 return 0;
1128
1129         printk(KERN_ERR PREFIX "Error attaching device data\n");
1130         return -ENODEV;
1131 }
1132
1133 static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
1134 {
1135         if (!dev)
1136                 return -EINVAL;
1137
1138         dev->removal_type = ACPI_BUS_REMOVAL_EJECT;
1139         device_release_driver(&dev->dev);
1140
1141         if (!rmdevice)
1142                 return 0;
1143
1144         /*
1145          * unbind _ADR-Based Devices when hot removal
1146          */
1147         if (dev->flags.bus_address) {
1148                 if ((dev->parent) && (dev->parent->ops.unbind))
1149                         dev->parent->ops.unbind(dev);
1150         }
1151         acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
1152
1153         return 0;
1154 }
1155
1156 static int acpi_add_single_object(struct acpi_device **child,
1157                                   acpi_handle handle, int type,
1158                                   unsigned long long sta,
1159                                   struct acpi_bus_ops *ops)
1160 {
1161         int result;
1162         struct acpi_device *device;
1163         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1164
1165         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1166         if (!device) {
1167                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1168                 return -ENOMEM;
1169         }
1170
1171         INIT_LIST_HEAD(&device->pnp.ids);
1172         device->device_type = type;
1173         device->handle = handle;
1174         device->parent = acpi_bus_get_parent(handle);
1175         device->bus_ops = *ops; /* workround for not call .start */
1176         STRUCT_TO_INT(device->status) = sta;
1177
1178         acpi_device_get_busid(device);
1179
1180         /*
1181          * Flags
1182          * -----
1183          * Note that we only look for object handles -- cannot evaluate objects
1184          * until we know the device is present and properly initialized.
1185          */
1186         result = acpi_bus_get_flags(device);
1187         if (result)
1188                 goto end;
1189
1190         /*
1191          * Initialize Device
1192          * -----------------
1193          * TBD: Synch with Core's enumeration/initialization process.
1194          */
1195         acpi_device_set_id(device);
1196
1197         /*
1198          * Power Management
1199          * ----------------
1200          */
1201         if (device->flags.power_manageable) {
1202                 result = acpi_bus_get_power_flags(device);
1203                 if (result)
1204                         goto end;
1205         }
1206
1207         /*
1208          * Wakeup device management
1209          *-----------------------
1210          */
1211         if (device->flags.wake_capable) {
1212                 result = acpi_bus_get_wakeup_device_flags(device);
1213                 if (result)
1214                         goto end;
1215         }
1216
1217         /*
1218          * Performance Management
1219          * ----------------------
1220          */
1221         if (device->flags.performance_manageable) {
1222                 result = acpi_bus_get_perf_flags(device);
1223                 if (result)
1224                         goto end;
1225         }
1226
1227         if ((result = acpi_device_set_context(device)))
1228                 goto end;
1229
1230         result = acpi_device_register(device);
1231
1232         /*
1233          * Bind _ADR-Based Devices when hot add
1234          */
1235         if (device->flags.bus_address) {
1236                 if (device->parent && device->parent->ops.bind)
1237                         device->parent->ops.bind(device);
1238         }
1239
1240 end:
1241         if (!result) {
1242                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1243                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1244                         "Adding %s [%s] parent %s\n", dev_name(&device->dev),
1245                          (char *) buffer.pointer,
1246                          device->parent ? dev_name(&device->parent->dev) :
1247                                           "(null)"));
1248                 kfree(buffer.pointer);
1249                 *child = device;
1250         } else
1251                 acpi_device_release(&device->dev);
1252
1253         return result;
1254 }
1255
1256 #define ACPI_STA_DEFAULT (ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED | \
1257                           ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING)
1258
1259 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1260                                     unsigned long long *sta)
1261 {
1262         acpi_status status;
1263         acpi_object_type acpi_type;
1264
1265         status = acpi_get_type(handle, &acpi_type);
1266         if (ACPI_FAILURE(status))
1267                 return -ENODEV;
1268
1269         switch (acpi_type) {
1270         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1271         case ACPI_TYPE_DEVICE:
1272                 *type = ACPI_BUS_TYPE_DEVICE;
1273                 status = acpi_bus_get_status_handle(handle, sta);
1274                 if (ACPI_FAILURE(status))
1275                         return -ENODEV;
1276                 break;
1277         case ACPI_TYPE_PROCESSOR:
1278                 *type = ACPI_BUS_TYPE_PROCESSOR;
1279                 status = acpi_bus_get_status_handle(handle, sta);
1280                 if (ACPI_FAILURE(status))
1281                         return -ENODEV;
1282                 break;
1283         case ACPI_TYPE_THERMAL:
1284                 *type = ACPI_BUS_TYPE_THERMAL;
1285                 *sta = ACPI_STA_DEFAULT;
1286                 break;
1287         case ACPI_TYPE_POWER:
1288                 *type = ACPI_BUS_TYPE_POWER;
1289                 *sta = ACPI_STA_DEFAULT;
1290                 break;
1291         default:
1292                 return -ENODEV;
1293         }
1294
1295         return 0;
1296 }
1297
1298 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl,
1299                                       void *context, void **return_value)
1300 {
1301         struct acpi_bus_ops *ops = context;
1302         int type;
1303         unsigned long long sta;
1304         struct acpi_device *device;
1305         acpi_status status;
1306         int result;
1307
1308         result = acpi_bus_type_and_status(handle, &type, &sta);
1309         if (result)
1310                 return AE_OK;
1311
1312         if (!(sta & ACPI_STA_DEVICE_PRESENT) &&
1313             !(sta & ACPI_STA_DEVICE_FUNCTIONING))
1314                 return AE_CTRL_DEPTH;
1315
1316         /*
1317          * We may already have an acpi_device from a previous enumeration.  If
1318          * so, we needn't add it again, but we may still have to start it.
1319          */
1320         device = NULL;
1321         acpi_bus_get_device(handle, &device);
1322         if (ops->acpi_op_add && !device)
1323                 acpi_add_single_object(&device, handle, type, sta, ops);
1324
1325         if (!device)
1326                 return AE_CTRL_DEPTH;
1327
1328         if (ops->acpi_op_start && !(ops->acpi_op_add)) {
1329                 status = acpi_start_single_object(device);
1330                 if (ACPI_FAILURE(status))
1331                         return AE_CTRL_DEPTH;
1332         }
1333
1334         if (!*return_value)
1335                 *return_value = device;
1336         return AE_OK;
1337 }
1338
1339 static int acpi_bus_scan(acpi_handle handle, struct acpi_bus_ops *ops,
1340                          struct acpi_device **child)
1341 {
1342         acpi_status status;
1343         void *device = NULL;
1344
1345         status = acpi_bus_check_add(handle, 0, ops, &device);
1346         if (ACPI_SUCCESS(status))
1347                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1348                                     acpi_bus_check_add, ops, &device);
1349
1350         if (child)
1351                 *child = device;
1352         return 0;
1353 }
1354
1355 int
1356 acpi_bus_add(struct acpi_device **child,
1357              struct acpi_device *parent, acpi_handle handle, int type)
1358 {
1359         struct acpi_bus_ops ops;
1360
1361         memset(&ops, 0, sizeof(ops));
1362         ops.acpi_op_add = 1;
1363
1364         acpi_bus_scan(handle, &ops, child);
1365         return 0;
1366 }
1367 EXPORT_SYMBOL(acpi_bus_add);
1368
1369 int acpi_bus_start(struct acpi_device *device)
1370 {
1371         struct acpi_bus_ops ops;
1372
1373         memset(&ops, 0, sizeof(ops));
1374         ops.acpi_op_start = 1;
1375
1376         acpi_bus_scan(device->handle, &ops, NULL);
1377         return 0;
1378 }
1379 EXPORT_SYMBOL(acpi_bus_start);
1380
1381 int acpi_bus_trim(struct acpi_device *start, int rmdevice)
1382 {
1383         acpi_status status;
1384         struct acpi_device *parent, *child;
1385         acpi_handle phandle, chandle;
1386         acpi_object_type type;
1387         u32 level = 1;
1388         int err = 0;
1389
1390         parent = start;
1391         phandle = start->handle;
1392         child = chandle = NULL;
1393
1394         while ((level > 0) && parent && (!err)) {
1395                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1396                                               chandle, &chandle);
1397
1398                 /*
1399                  * If this scope is exhausted then move our way back up.
1400                  */
1401                 if (ACPI_FAILURE(status)) {
1402                         level--;
1403                         chandle = phandle;
1404                         acpi_get_parent(phandle, &phandle);
1405                         child = parent;
1406                         parent = parent->parent;
1407
1408                         if (level == 0)
1409                                 err = acpi_bus_remove(child, rmdevice);
1410                         else
1411                                 err = acpi_bus_remove(child, 1);
1412
1413                         continue;
1414                 }
1415
1416                 status = acpi_get_type(chandle, &type);
1417                 if (ACPI_FAILURE(status)) {
1418                         continue;
1419                 }
1420                 /*
1421                  * If there is a device corresponding to chandle then
1422                  * parse it (depth-first).
1423                  */
1424                 if (acpi_bus_get_device(chandle, &child) == 0) {
1425                         level++;
1426                         phandle = chandle;
1427                         chandle = NULL;
1428                         parent = child;
1429                 }
1430                 continue;
1431         }
1432         return err;
1433 }
1434 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1435
1436 static int acpi_bus_scan_fixed(void)
1437 {
1438         int result = 0;
1439         struct acpi_device *device = NULL;
1440         struct acpi_bus_ops ops;
1441
1442         memset(&ops, 0, sizeof(ops));
1443         ops.acpi_op_add = 1;
1444         ops.acpi_op_start = 1;
1445
1446         /*
1447          * Enumerate all fixed-feature devices.
1448          */
1449         if ((acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON) == 0) {
1450                 result = acpi_add_single_object(&device, NULL,
1451                                                 ACPI_BUS_TYPE_POWER_BUTTON,
1452                                                 ACPI_STA_DEFAULT,
1453                                                 &ops);
1454         }
1455
1456         if ((acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON) == 0) {
1457                 result = acpi_add_single_object(&device, NULL,
1458                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
1459                                                 ACPI_STA_DEFAULT,
1460                                                 &ops);
1461         }
1462
1463         return result;
1464 }
1465
1466 int __init acpi_scan_init(void)
1467 {
1468         int result;
1469         struct acpi_bus_ops ops;
1470
1471         memset(&ops, 0, sizeof(ops));
1472         ops.acpi_op_add = 1;
1473         ops.acpi_op_start = 1;
1474
1475         result = bus_register(&acpi_bus_type);
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 bus type\n");
1479         }
1480
1481         /*
1482          * Enumerate devices in the ACPI namespace.
1483          */
1484         result = acpi_bus_scan(ACPI_ROOT_OBJECT, &ops, &acpi_root);
1485
1486         if (!result)
1487                 result = acpi_bus_scan_fixed();
1488
1489         if (result)
1490                 acpi_device_unregister(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
1491
1492         return result;
1493 }