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         if (!acpi_dev->flags.hardware_id && !acpi_dev->flags.compatible_ids)
  51                 return -ENODEV;
  52
  53         len = snprintf(modalias, size, "acpi:");
  54         size -= len;
  55
  56         list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
  57                 count = snprintf(&modalias[len], size, "%s:", id->id);
  58                 if (count < 0 || count >= size)
  59                         return -EINVAL;
  60                 len += count;
  61                 size -= count;
  62         }
  63
  64         modalias[len] = '\0';
  65         return len;
  66 }
  67
  68 static ssize_t
  69 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
  70         struct acpi_device *acpi_dev = to_acpi_device(dev);
  71         int len;
  72
  73         /* Device has no HID and no CID or string is >1024 */
  74         len = create_modalias(acpi_dev, buf, 1024);
  75         if (len <= 0)
  76                 return 0;
  77         buf[len++] = '\n';
  78         return len;
  79 }
  80 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
  81
  82 static void acpi_bus_hot_remove_device(void *context)
  83 {
  84         struct acpi_device *device;
  85         acpi_handle handle = context;
  86         struct acpi_object_list arg_list;
  87         union acpi_object arg;
  88         acpi_status status = AE_OK;
  89
  90         if (acpi_bus_get_device(handle, &device))
  91                 return;
  92
  93         if (!device)
  94                 return;
  95
  96         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
  97                 "Hot-removing device %s...\n", dev_name(&device->dev)));
  98
  99         if (acpi_bus_trim(device, 1)) {
 100                 printk(KERN_ERR PREFIX
 101                                 "Removing device failed\n");
 102                 return;
 103         }
 104
 105         /* power off device */
 106         status = acpi_evaluate_object(handle, "_PS3", NULL, NULL);
 107         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
 108                 printk(KERN_WARNING PREFIX
 109                                 "Power-off device failed\n");
 110
 111         if (device->flags.lockable) {
 112                 arg_list.count = 1;
 113                 arg_list.pointer = &arg;
 114                 arg.type = ACPI_TYPE_INTEGER;
 115                 arg.integer.value = 0;
 116                 acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
 117         }
 118
 119         arg_list.count = 1;
 120         arg_list.pointer = &arg;
 121         arg.type = ACPI_TYPE_INTEGER;
 122         arg.integer.value = 1;
 123
 124         /*
 125          * TBD: _EJD support.
 126          */
 127         status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
 128         if (ACPI_FAILURE(status))
 129                 printk(KERN_WARNING PREFIX
 130                                 "Eject device failed\n");
 131
 132         return;
 133 }
 134
 135 static ssize_t
 136 acpi_eject_store(struct device *d, struct device_attribute *attr,
 137                 const char *buf, size_t count)
 138 {
 139         int ret = count;
 140         acpi_status status;
 141         acpi_object_type type = 0;
 142         struct acpi_device *acpi_device = to_acpi_device(d);
 143
 144         if ((!count) || (buf[0] != '1')) {
 145                 return -EINVAL;
 146         }
 147 #ifndef FORCE_EJECT
 148         if (acpi_device->driver == NULL) {
 149                 ret = -ENODEV;
 150                 goto err;
 151         }
 152 #endif
 153         status = acpi_get_type(acpi_device->handle, &type);
 154         if (ACPI_FAILURE(status) || (!acpi_device->flags.ejectable)) {
 155                 ret = -ENODEV;
 156                 goto err;
 157         }
 158
 159         acpi_os_hotplug_execute(acpi_bus_hot_remove_device, acpi_device->handle);
 160 err:
 161         return ret;
 162 }
 163
 164 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
 165
 166 static ssize_t
 167 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
 168         struct acpi_device *acpi_dev = to_acpi_device(dev);
 169
 170         return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
 171 }
 172 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
 173
 174 static ssize_t
 175 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
 176         struct acpi_device *acpi_dev = to_acpi_device(dev);
 177         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
 178         int result;
 179
 180         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
 181         if (result)
 182                 goto end;
 183
 184         result = sprintf(buf, "%s\n", (char*)path.pointer);
 185         kfree(path.pointer);
 186 end:
 187         return result;
 188 }
 189 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
 190
 191 static int acpi_device_setup_files(struct acpi_device *dev)
 192 {
 193         acpi_status status;
 194         acpi_handle temp;
 195         int result = 0;
 196
 197         /*
 198          * Devices gotten from FADT don't have a "path" attribute
 199          */
 200         if (dev->handle) {
 201                 result = device_create_file(&dev->dev, &dev_attr_path);
 202                 if (result)
 203                         goto end;
 204         }
 205
 206         if (dev->flags.hardware_id) {
 207                 result = device_create_file(&dev->dev, &dev_attr_hid);
 208                 if (result)
 209                         goto end;
 210         }
 211
 212         if (dev->flags.hardware_id || dev->flags.compatible_ids) {
 213                 result = device_create_file(&dev->dev, &dev_attr_modalias);
 214                 if (result)
 215                         goto end;
 216         }
 217
 218         /*
 219          * If device has _EJ0, 'eject' file is created that is used to trigger
 220          * hot-removal function from userland.
 221          */
 222         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 223         if (ACPI_SUCCESS(status))
 224                 result = device_create_file(&dev->dev, &dev_attr_eject);
 225 end:
 226         return result;
 227 }
 228
 229 static void acpi_device_remove_files(struct acpi_device *dev)
 230 {
 231         acpi_status status;
 232         acpi_handle temp;
 233
 234         /*
 235          * If device has _EJ0, 'eject' file is created that is used to trigger
 236          * hot-removal function from userland.
 237          */
 238         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 239         if (ACPI_SUCCESS(status))
 240                 device_remove_file(&dev->dev, &dev_attr_eject);
 241
 242         if (dev->flags.hardware_id || dev->flags.compatible_ids)
 243                 device_remove_file(&dev->dev, &dev_attr_modalias);
 244
 245         if (dev->flags.hardware_id)
 246                 device_remove_file(&dev->dev, &dev_attr_hid);
 247         if (dev->handle)
 248                 device_remove_file(&dev->dev, &dev_attr_path);
 249 }
 250 /* --------------------------------------------------------------------------
 251                         ACPI Bus operations
 252    -------------------------------------------------------------------------- */
 253
 254 int acpi_match_device_ids(struct acpi_device *device,
 255                           const struct acpi_device_id *ids)
 256 {
 257         const struct acpi_device_id *id;
 258         struct acpi_hardware_id *hwid;
 259
 260         /*
 261          * If the device is not present, it is unnecessary to load device
 262          * driver for it.
 263          */
 264         if (!device->status.present)
 265                 return -ENODEV;
 266
 267         for (id = ids; id->id[0]; id++)
 268                 list_for_each_entry(hwid, &device->pnp.ids, list)
 269                         if (!strcmp((char *) id->id, hwid->id))
 270                                 return 0;
 271
 272         return -ENOENT;
 273 }
 274 EXPORT_SYMBOL(acpi_match_device_ids);
 275
 276 static void acpi_free_ids(struct acpi_device *device)
 277 {
 278         struct acpi_hardware_id *id, *tmp;
 279
 280         list_for_each_entry_safe(id, tmp, &device->pnp.ids, list) {
 281                 kfree(id->id);
 282                 kfree(id);
 283         }
 284 }
 285
 286 static void acpi_device_release(struct device *dev)
 287 {
 288         struct acpi_device *acpi_dev = to_acpi_device(dev);
 289
 290         acpi_free_ids(acpi_dev);
 291         kfree(acpi_dev);
 292 }
 293
 294 static int acpi_device_suspend(struct device *dev, pm_message_t state)
 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.suspend)
 300                 return acpi_drv->ops.suspend(acpi_dev, state);
 301         return 0;
 302 }
 303
 304 static int acpi_device_resume(struct device *dev)
 305 {
 306         struct acpi_device *acpi_dev = to_acpi_device(dev);
 307         struct acpi_driver *acpi_drv = acpi_dev->driver;
 308
 309         if (acpi_drv && acpi_drv->ops.resume)
 310                 return acpi_drv->ops.resume(acpi_dev);
 311         return 0;
 312 }
 313
 314 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
 315 {
 316         struct acpi_device *acpi_dev = to_acpi_device(dev);
 317         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
 318
 319         return !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
 320 }
 321
 322 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
 323 {
 324         struct acpi_device *acpi_dev = to_acpi_device(dev);
 325         int len;
 326
 327         if (add_uevent_var(env, "MODALIAS="))
 328                 return -ENOMEM;
 329         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
 330                               sizeof(env->buf) - env->buflen);
 331         if (len >= (sizeof(env->buf) - env->buflen))
 332                 return -ENOMEM;
 333         env->buflen += len;
 334         return 0;
 335 }
 336
 337 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
 338 {
 339         struct acpi_device *device = data;
 340
 341         device->driver->ops.notify(device, event);
 342 }
 343
 344 static acpi_status acpi_device_notify_fixed(void *data)
 345 {
 346         struct acpi_device *device = data;
 347
 348         /* Fixed hardware devices have no handles */
 349         acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
 350         return AE_OK;
 351 }
 352
 353 static int acpi_device_install_notify_handler(struct acpi_device *device)
 354 {
 355         acpi_status status;
 356
 357         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 358                 status =
 359                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 360                                                      acpi_device_notify_fixed,
 361                                                      device);
 362         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 363                 status =
 364                     acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 365                                                      acpi_device_notify_fixed,
 366                                                      device);
 367         else
 368                 status = acpi_install_notify_handler(device->handle,
 369                                                      ACPI_DEVICE_NOTIFY,
 370                                                      acpi_device_notify,
 371                                                      device);
 372
 373         if (ACPI_FAILURE(status))
 374                 return -EINVAL;
 375         return 0;
 376 }
 377
 378 static void acpi_device_remove_notify_handler(struct acpi_device *device)
 379 {
 380         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 381                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 382                                                 acpi_device_notify_fixed);
 383         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 384                 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 385                                                 acpi_device_notify_fixed);
 386         else
 387                 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
 388                                            acpi_device_notify);
 389 }
 390
 391 static int acpi_bus_driver_init(struct acpi_device *, struct acpi_driver *);
 392 static int acpi_start_single_object(struct acpi_device *);
 393 static int acpi_device_probe(struct device * dev)
 394 {
 395         struct acpi_device *acpi_dev = to_acpi_device(dev);
 396         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
 397         int ret;
 398
 399         ret = acpi_bus_driver_init(acpi_dev, acpi_drv);
 400         if (!ret) {
 401                 if (acpi_dev->bus_ops.acpi_op_start)
 402                         acpi_start_single_object(acpi_dev);
 403
 404                 if (acpi_drv->ops.notify) {
 405                         ret = acpi_device_install_notify_handler(acpi_dev);
 406                         if (ret) {
 407                                 if (acpi_drv->ops.remove)
 408                                         acpi_drv->ops.remove(acpi_dev,
 409                                                      acpi_dev->removal_type);
 410                                 return ret;
 411                         }
 412                 }
 413
 414                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 415                         "Found driver [%s] for device [%s]\n",
 416                         acpi_drv->name, acpi_dev->pnp.bus_id));
 417                 get_device(dev);
 418         }
 419         return ret;
 420 }
 421
 422 static int acpi_device_remove(struct device * dev)
 423 {
 424         struct acpi_device *acpi_dev = to_acpi_device(dev);
 425         struct acpi_driver *acpi_drv = acpi_dev->driver;
 426
 427         if (acpi_drv) {
 428                 if (acpi_drv->ops.notify)
 429                         acpi_device_remove_notify_handler(acpi_dev);
 430                 if (acpi_drv->ops.remove)
 431                         acpi_drv->ops.remove(acpi_dev, acpi_dev->removal_type);
 432         }
 433         acpi_dev->driver = NULL;
 434         acpi_dev->driver_data = NULL;
 435
 436         put_device(dev);
 437         return 0;
 438 }
 439
 440 struct bus_type acpi_bus_type = {
 441         .name           = "acpi",
 442         .suspend        = acpi_device_suspend,
 443         .resume         = acpi_device_resume,
 444         .match          = acpi_bus_match,
 445         .probe          = acpi_device_probe,
 446         .remove         = acpi_device_remove,
 447         .uevent         = acpi_device_uevent,
 448 };
 449
 450 static int acpi_device_register(struct acpi_device *device)
 451 {
 452         int result;
 453         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
 454         int found = 0;
 455
 456         /*
 457          * Linkage
 458          * -------
 459          * Link this device to its parent and siblings.
 460          */
 461         INIT_LIST_HEAD(&device->children);
 462         INIT_LIST_HEAD(&device->node);
 463         INIT_LIST_HEAD(&device->wakeup_list);
 464
 465         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
 466         if (!new_bus_id) {
 467                 printk(KERN_ERR PREFIX "Memory allocation error\n");
 468                 return -ENOMEM;
 469         }
 470
 471         mutex_lock(&acpi_device_lock);
 472         /*
 473          * Find suitable bus_id and instance number in acpi_bus_id_list
 474          * If failed, create one and link it into acpi_bus_id_list
 475          */
 476         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
 477                 if (!strcmp(acpi_device_bus_id->bus_id, device->flags.hardware_id ? acpi_device_hid(device) : "device")) {
 478                         acpi_device_bus_id->instance_no ++;
 479                         found = 1;
 480                         kfree(new_bus_id);
 481                         break;
 482                 }
 483         }
 484         if (!found) {
 485                 acpi_device_bus_id = new_bus_id;
 486                 strcpy(acpi_device_bus_id->bus_id, device->flags.hardware_id ? acpi_device_hid(device) : "device");
 487                 acpi_device_bus_id->instance_no = 0;
 488                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
 489         }
 490         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
 491
 492         if (device->parent)
 493                 list_add_tail(&device->node, &device->parent->children);
 494
 495         if (device->wakeup.flags.valid)
 496                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
 497         mutex_unlock(&acpi_device_lock);
 498
 499         if (device->parent)
 500                 device->dev.parent = &device->parent->dev;
 501         device->dev.bus = &acpi_bus_type;
 502         device->dev.release = &acpi_device_release;
 503         result = device_register(&device->dev);
 504         if (result) {
 505                 dev_err(&device->dev, "Error registering device\n");
 506                 goto end;
 507         }
 508
 509         result = acpi_device_setup_files(device);
 510         if (result)
 511                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
 512                        dev_name(&device->dev));
 513
 514         device->removal_type = ACPI_BUS_REMOVAL_NORMAL;
 515         return 0;
 516 end:
 517         mutex_lock(&acpi_device_lock);
 518         if (device->parent)
 519                 list_del(&device->node);
 520         list_del(&device->wakeup_list);
 521         mutex_unlock(&acpi_device_lock);
 522         return result;
 523 }
 524
 525 static void acpi_device_unregister(struct acpi_device *device, int type)
 526 {
 527         mutex_lock(&acpi_device_lock);
 528         if (device->parent)
 529                 list_del(&device->node);
 530
 531         list_del(&device->wakeup_list);
 532         mutex_unlock(&acpi_device_lock);
 533
 534         acpi_detach_data(device->handle, acpi_bus_data_handler);
 535
 536         acpi_device_remove_files(device);
 537         device_unregister(&device->dev);
 538 }
 539
 540 /* --------------------------------------------------------------------------
 541                                  Driver Management
 542    -------------------------------------------------------------------------- */
 543 /**
 544  * acpi_bus_driver_init - add a device to a driver
 545  * @device: the device to add and initialize
 546  * @driver: driver for the device
 547  *
 548  * Used to initialize a device via its device driver.  Called whenever a
 549  * driver is bound to a device.  Invokes the driver's add() ops.
 550  */
 551 static int
 552 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
 553 {
 554         int result = 0;
 555
 556         if (!device || !driver)
 557                 return -EINVAL;
 558
 559         if (!driver->ops.add)
 560                 return -ENOSYS;
 561
 562         result = driver->ops.add(device);
 563         if (result) {
 564                 device->driver = NULL;
 565                 device->driver_data = NULL;
 566                 return result;
 567         }
 568
 569         device->driver = driver;
 570
 571         /*
 572          * TBD - Configuration Management: Assign resources to device based
 573          * upon possible configuration and currently allocated resources.
 574          */
 575
 576         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 577                           "Driver successfully bound to device\n"));
 578         return 0;
 579 }
 580
 581 static int acpi_start_single_object(struct acpi_device *device)
 582 {
 583         int result = 0;
 584         struct acpi_driver *driver;
 585
 586
 587         if (!(driver = device->driver))
 588                 return 0;
 589
 590         if (driver->ops.start) {
 591                 result = driver->ops.start(device);
 592                 if (result && driver->ops.remove)
 593                         driver->ops.remove(device, ACPI_BUS_REMOVAL_NORMAL);
 594         }
 595
 596         return result;
 597 }
 598
 599 /**
 600  * acpi_bus_register_driver - register a driver with the ACPI bus
 601  * @driver: driver being registered
 602  *
 603  * Registers a driver with the ACPI bus.  Searches the namespace for all
 604  * devices that match the driver's criteria and binds.  Returns zero for
 605  * success or a negative error status for failure.
 606  */
 607 int acpi_bus_register_driver(struct acpi_driver *driver)
 608 {
 609         int ret;
 610
 611         if (acpi_disabled)
 612                 return -ENODEV;
 613         driver->drv.name = driver->name;
 614         driver->drv.bus = &acpi_bus_type;
 615         driver->drv.owner = driver->owner;
 616
 617         ret = driver_register(&driver->drv);
 618         return ret;
 619 }
 620
 621 EXPORT_SYMBOL(acpi_bus_register_driver);
 622
 623 /**
 624  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
 625  * @driver: driver to unregister
 626  *
 627  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
 628  * devices that match the driver's criteria and unbinds.
 629  */
 630 void acpi_bus_unregister_driver(struct acpi_driver *driver)
 631 {
 632         driver_unregister(&driver->drv);
 633 }
 634
 635 EXPORT_SYMBOL(acpi_bus_unregister_driver);
 636
 637 /* --------------------------------------------------------------------------
 638                                  Device Enumeration
 639    -------------------------------------------------------------------------- */
 640 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
 641 {
 642         acpi_status status;
 643         int ret;
 644         struct acpi_device *device;
 645
 646         /*
 647          * Fixed hardware devices do not appear in the namespace and do not
 648          * have handles, but we fabricate acpi_devices for them, so we have
 649          * to deal with them specially.
 650          */
 651         if (handle == NULL)
 652                 return acpi_root;
 653
 654         do {
 655                 status = acpi_get_parent(handle, &handle);
 656                 if (status == AE_NULL_ENTRY)
 657                         return NULL;
 658                 if (ACPI_FAILURE(status))
 659                         return acpi_root;
 660
 661                 ret = acpi_bus_get_device(handle, &device);
 662                 if (ret == 0)
 663                         return device;
 664         } while (1);
 665 }
 666
 667 acpi_status
 668 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
 669 {
 670         acpi_status status;
 671         acpi_handle tmp;
 672         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 673         union acpi_object *obj;
 674
 675         status = acpi_get_handle(handle, "_EJD", &tmp);
 676         if (ACPI_FAILURE(status))
 677                 return status;
 678
 679         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
 680         if (ACPI_SUCCESS(status)) {
 681                 obj = buffer.pointer;
 682                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
 683                                          ejd);
 684                 kfree(buffer.pointer);
 685         }
 686         return status;
 687 }
 688 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
 689
 690 void acpi_bus_data_handler(acpi_handle handle, void *context)
 691 {
 692
 693         /* TBD */
 694
 695         return;
 696 }
 697
 698 static int acpi_bus_get_perf_flags(struct acpi_device *device)
 699 {
 700         device->performance.state = ACPI_STATE_UNKNOWN;
 701         return 0;
 702 }
 703
 704 static acpi_status
 705 acpi_bus_extract_wakeup_device_power_package(struct acpi_device *device,
 706                                              union acpi_object *package)
 707 {
 708         int i = 0;
 709         union acpi_object *element = NULL;
 710
 711         if (!device || !package || (package->package.count < 2))
 712                 return AE_BAD_PARAMETER;
 713
 714         element = &(package->package.elements[0]);
 715         if (!element)
 716                 return AE_BAD_PARAMETER;
 717         if (element->type == ACPI_TYPE_PACKAGE) {
 718                 if ((element->package.count < 2) ||
 719                     (element->package.elements[0].type !=
 720                      ACPI_TYPE_LOCAL_REFERENCE)
 721                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
 722                         return AE_BAD_DATA;
 723                 device->wakeup.gpe_device =
 724                     element->package.elements[0].reference.handle;
 725                 device->wakeup.gpe_number =
 726                     (u32) element->package.elements[1].integer.value;
 727         } else if (element->type == ACPI_TYPE_INTEGER) {
 728                 device->wakeup.gpe_number = element->integer.value;
 729         } else
 730                 return AE_BAD_DATA;
 731
 732         element = &(package->package.elements[1]);
 733         if (element->type != ACPI_TYPE_INTEGER) {
 734                 return AE_BAD_DATA;
 735         }
 736         device->wakeup.sleep_state = element->integer.value;
 737
 738         if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
 739                 return AE_NO_MEMORY;
 740         }
 741         device->wakeup.resources.count = package->package.count - 2;
 742         for (i = 0; i < device->wakeup.resources.count; i++) {
 743                 element = &(package->package.elements[i + 2]);
 744                 if (element->type != ACPI_TYPE_LOCAL_REFERENCE)
 745                         return AE_BAD_DATA;
 746
 747                 device->wakeup.resources.handles[i] = element->reference.handle;
 748         }
 749
 750         return AE_OK;
 751 }
 752
 753 static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
 754 {
 755         acpi_status status = 0;
 756         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 757         union acpi_object *package = NULL;
 758         int psw_error;
 759
 760         struct acpi_device_id button_device_ids[] = {
 761                 {"PNP0C0D", 0},
 762                 {"PNP0C0C", 0},
 763                 {"PNP0C0E", 0},
 764                 {"", 0},
 765         };
 766
 767         /* _PRW */
 768         status = acpi_evaluate_object(device->handle, "_PRW", NULL, &buffer);
 769         if (ACPI_FAILURE(status)) {
 770                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
 771                 goto end;
 772         }
 773
 774         package = (union acpi_object *)buffer.pointer;
 775         status = acpi_bus_extract_wakeup_device_power_package(device, package);
 776         if (ACPI_FAILURE(status)) {
 777                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _PRW package"));
 778                 goto end;
 779         }
 780
 781         kfree(buffer.pointer);
 782
 783         device->wakeup.flags.valid = 1;
 784         device->wakeup.prepare_count = 0;
 785         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
 786          * system for the ACPI device with the _PRW object.
 787          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
 788          * So it is necessary to call _DSW object first. Only when it is not
 789          * present will the _PSW object used.
 790          */
 791         psw_error = acpi_device_sleep_wake(device, 0, 0, 0);
 792         if (psw_error)
 793                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 794                                 "error in _DSW or _PSW evaluation\n"));
 795
 796         /* Power button, Lid switch always enable wakeup */
 797         if (!acpi_match_device_ids(device, button_device_ids))
 798                 device->wakeup.flags.run_wake = 1;
 799
 800 end:
 801         if (ACPI_FAILURE(status))
 802                 device->flags.wake_capable = 0;
 803         return 0;
 804 }
 805
 806 static int acpi_bus_get_power_flags(struct acpi_device *device)
 807 {
 808         acpi_status status = 0;
 809         acpi_handle handle = NULL;
 810         u32 i = 0;
 811
 812
 813         /*
 814          * Power Management Flags
 815          */
 816         status = acpi_get_handle(device->handle, "_PSC", &handle);
 817         if (ACPI_SUCCESS(status))
 818                 device->power.flags.explicit_get = 1;
 819         status = acpi_get_handle(device->handle, "_IRC", &handle);
 820         if (ACPI_SUCCESS(status))
 821                 device->power.flags.inrush_current = 1;
 822
 823         /*
 824          * Enumerate supported power management states
 825          */
 826         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
 827                 struct acpi_device_power_state *ps = &device->power.states[i];
 828                 char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
 829
 830                 /* Evaluate "_PRx" to se if power resources are referenced */
 831                 acpi_evaluate_reference(device->handle, object_name, NULL,
 832                                         &ps->resources);
 833                 if (ps->resources.count) {
 834                         device->power.flags.power_resources = 1;
 835                         ps->flags.valid = 1;
 836                 }
 837
 838                 /* Evaluate "_PSx" to see if we can do explicit sets */
 839                 object_name[2] = 'S';
 840                 status = acpi_get_handle(device->handle, object_name, &handle);
 841                 if (ACPI_SUCCESS(status)) {
 842                         ps->flags.explicit_set = 1;
 843                         ps->flags.valid = 1;
 844                 }
 845
 846                 /* State is valid if we have some power control */
 847                 if (ps->resources.count || ps->flags.explicit_set)
 848                         ps->flags.valid = 1;
 849
 850                 ps->power = -1; /* Unknown - driver assigned */
 851                 ps->latency = -1;       /* Unknown - driver assigned */
 852         }
 853
 854         /* Set defaults for D0 and D3 states (always valid) */
 855         device->power.states[ACPI_STATE_D0].flags.valid = 1;
 856         device->power.states[ACPI_STATE_D0].power = 100;
 857         device->power.states[ACPI_STATE_D3].flags.valid = 1;
 858         device->power.states[ACPI_STATE_D3].power = 0;
 859
 860         /* TBD: System wake support and resource requirements. */
 861
 862         device->power.state = ACPI_STATE_UNKNOWN;
 863         acpi_bus_get_power(device->handle, &(device->power.state));
 864
 865         return 0;
 866 }
 867
 868 static int acpi_bus_get_flags(struct acpi_device *device)
 869 {
 870         acpi_status status = AE_OK;
 871         acpi_handle temp = NULL;
 872
 873
 874         /* Presence of _STA indicates 'dynamic_status' */
 875         status = acpi_get_handle(device->handle, "_STA", &temp);
 876         if (ACPI_SUCCESS(status))
 877                 device->flags.dynamic_status = 1;
 878
 879         /* Presence of _CID indicates 'compatible_ids' */
 880         status = acpi_get_handle(device->handle, "_CID", &temp);
 881         if (ACPI_SUCCESS(status))
 882                 device->flags.compatible_ids = 1;
 883
 884         /* Presence of _RMV indicates 'removable' */
 885         status = acpi_get_handle(device->handle, "_RMV", &temp);
 886         if (ACPI_SUCCESS(status))
 887                 device->flags.removable = 1;
 888
 889         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
 890         status = acpi_get_handle(device->handle, "_EJD", &temp);
 891         if (ACPI_SUCCESS(status))
 892                 device->flags.ejectable = 1;
 893         else {
 894                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
 895                 if (ACPI_SUCCESS(status))
 896                         device->flags.ejectable = 1;
 897         }
 898
 899         /* Presence of _LCK indicates 'lockable' */
 900         status = acpi_get_handle(device->handle, "_LCK", &temp);
 901         if (ACPI_SUCCESS(status))
 902                 device->flags.lockable = 1;
 903
 904         /* Presence of _PS0|_PR0 indicates 'power manageable' */
 905         status = acpi_get_handle(device->handle, "_PS0", &temp);
 906         if (ACPI_FAILURE(status))
 907                 status = acpi_get_handle(device->handle, "_PR0", &temp);
 908         if (ACPI_SUCCESS(status))
 909                 device->flags.power_manageable = 1;
 910
 911         /* Presence of _PRW indicates wake capable */
 912         status = acpi_get_handle(device->handle, "_PRW", &temp);
 913         if (ACPI_SUCCESS(status))
 914                 device->flags.wake_capable = 1;
 915
 916         /* TBD: Performance management */
 917
 918         return 0;
 919 }
 920
 921 static void acpi_device_get_busid(struct acpi_device *device)
 922 {
 923         char bus_id[5] = { '?', 0 };
 924         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
 925         int i = 0;
 926
 927         /*
 928          * Bus ID
 929          * ------
 930          * The device's Bus ID is simply the object name.
 931          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
 932          */
 933         if (ACPI_IS_ROOT_DEVICE(device)) {
 934                 strcpy(device->pnp.bus_id, "ACPI");
 935                 return;
 936         }
 937
 938         switch (device->device_type) {
 939         case ACPI_BUS_TYPE_POWER_BUTTON:
 940                 strcpy(device->pnp.bus_id, "PWRF");
 941                 break;
 942         case ACPI_BUS_TYPE_SLEEP_BUTTON:
 943                 strcpy(device->pnp.bus_id, "SLPF");
 944                 break;
 945         default:
 946                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
 947                 /* Clean up trailing underscores (if any) */
 948                 for (i = 3; i > 1; i--) {
 949                         if (bus_id[i] == '_')
 950                                 bus_id[i] = '\0';
 951                         else
 952                                 break;
 953                 }
 954                 strcpy(device->pnp.bus_id, bus_id);
 955                 break;
 956         }
 957 }
 958
 959 /*
 960  * acpi_bay_match - see if a device is an ejectable driver bay
 961  *
 962  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
 963  * then we can safely call it an ejectable drive bay
 964  */
 965 static int acpi_bay_match(struct acpi_device *device){
 966         acpi_status status;
 967         acpi_handle handle;
 968         acpi_handle tmp;
 969         acpi_handle phandle;
 970
 971         handle = device->handle;
 972
 973         status = acpi_get_handle(handle, "_EJ0", &tmp);
 974         if (ACPI_FAILURE(status))
 975                 return -ENODEV;
 976
 977         if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
 978                 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
 979                 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
 980                 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
 981                 return 0;
 982
 983         if (acpi_get_parent(handle, &phandle))
 984                 return -ENODEV;
 985
 986         if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
 987                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
 988                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
 989                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
 990                 return 0;
 991
 992         return -ENODEV;
 993 }
 994
 995 /*
 996  * acpi_dock_match - see if a device has a _DCK method
 997  */
 998 static int acpi_dock_match(struct acpi_device *device)
 999 {
1000         acpi_handle tmp;
1001         return acpi_get_handle(device->handle, "_DCK", &tmp);
1002 }
1003
1004 char *acpi_device_hid(struct acpi_device *device)
1005 {
1006         struct acpi_hardware_id *hid;
1007
1008         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1009         return hid->id;
1010 }
1011 EXPORT_SYMBOL(acpi_device_hid);
1012
1013 static void acpi_add_id(struct acpi_device *device, const char *dev_id)
1014 {
1015         struct acpi_hardware_id *id;
1016
1017         id = kmalloc(sizeof(*id), GFP_KERNEL);
1018         if (!id)
1019                 return;
1020
1021         id->id = kmalloc(strlen(dev_id) + 1, GFP_KERNEL);
1022         if (!id->id) {
1023                 kfree(id);
1024                 return;
1025         }
1026
1027         strcpy(id->id, dev_id);
1028         list_add_tail(&id->list, &device->pnp.ids);
1029 }
1030
1031 static void acpi_device_set_id(struct acpi_device *device)
1032 {
1033         struct acpi_device_info *info = NULL;
1034         char *hid = NULL;
1035         char *uid = NULL;
1036         struct acpica_device_id_list *cid_list = NULL;
1037         char *cid_add = NULL;
1038         acpi_status status;
1039         int i;
1040
1041         switch (device->device_type) {
1042         case ACPI_BUS_TYPE_DEVICE:
1043                 if (ACPI_IS_ROOT_DEVICE(device)) {
1044                         hid = ACPI_SYSTEM_HID;
1045                         break;
1046                 } else if (ACPI_IS_ROOT_DEVICE(device->parent)) {
1047                         /* \_SB_, the only root-level namespace device */
1048                         hid = ACPI_BUS_HID;
1049                         strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
1050                         strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
1051                         break;
1052                 }
1053
1054                 status = acpi_get_object_info(device->handle, &info);
1055                 if (ACPI_FAILURE(status)) {
1056                         printk(KERN_ERR PREFIX "%s: Error reading device info\n", __func__);
1057                         return;
1058                 }
1059
1060                 if (info->valid & ACPI_VALID_HID)
1061                         hid = info->hardware_id.string;
1062                 if (info->valid & ACPI_VALID_UID)
1063                         uid = info->unique_id.string;
1064                 if (info->valid & ACPI_VALID_CID)
1065                         cid_list = &info->compatible_id_list;
1066                 if (info->valid & ACPI_VALID_ADR) {
1067                         device->pnp.bus_address = info->address;
1068                         device->flags.bus_address = 1;
1069                 }
1070
1071                 /* If we have a video/bay/dock device, add our selfdefined
1072                    HID to the CID list. Like that the video/bay/dock drivers
1073                    will get autoloaded and the device might still match
1074                    against another driver.
1075                 */
1076                 if (acpi_is_video_device(device))
1077                         cid_add = ACPI_VIDEO_HID;
1078                 else if (ACPI_SUCCESS(acpi_bay_match(device)))
1079                         cid_add = ACPI_BAY_HID;
1080                 else if (ACPI_SUCCESS(acpi_dock_match(device)))
1081                         cid_add = ACPI_DOCK_HID;
1082
1083                 break;
1084         case ACPI_BUS_TYPE_POWER:
1085                 hid = ACPI_POWER_HID;
1086                 break;
1087         case ACPI_BUS_TYPE_PROCESSOR:
1088                 hid = ACPI_PROCESSOR_OBJECT_HID;
1089                 break;
1090         case ACPI_BUS_TYPE_THERMAL:
1091                 hid = ACPI_THERMAL_HID;
1092                 break;
1093         case ACPI_BUS_TYPE_POWER_BUTTON:
1094                 hid = ACPI_BUTTON_HID_POWERF;
1095                 break;
1096         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1097                 hid = ACPI_BUTTON_HID_SLEEPF;
1098                 break;
1099         }
1100
1101         /*
1102          * We build acpi_devices for some objects that don't have _HID or _CID,
1103          * e.g., PCI bridges and slots.  Drivers can't bind to these objects,
1104          * but we do use them indirectly by traversing the acpi_device tree.
1105          * This generic ID isn't useful for driver binding, but it provides
1106          * the useful property that "every acpi_device has an ID."
1107          */
1108         if (!hid && !cid_list && !cid_add)
1109                 hid = "device";
1110
1111         if (hid) {
1112                 acpi_add_id(device, hid);
1113                 device->flags.hardware_id = 1;
1114         }
1115         if (uid) {
1116                 device->pnp.unique_id = ACPI_ALLOCATE_ZEROED(strlen (uid) + 1);
1117                 if (device->pnp.unique_id) {
1118                         strcpy(device->pnp.unique_id, uid);
1119                         device->flags.unique_id = 1;
1120                 }
1121         }
1122         if (!device->flags.unique_id)
1123                 device->pnp.unique_id = "";
1124
1125         if (cid_list)
1126                 for (i = 0; i < cid_list->count; i++)
1127                         acpi_add_id(device, cid_list->ids[i].string);
1128         if (cid_add) {
1129                 acpi_add_id(device, cid_add);
1130                 device->flags.compatible_ids = 1;
1131         }
1132
1133         kfree(info);
1134 }
1135
1136 static int acpi_device_set_context(struct acpi_device *device)
1137 {
1138         acpi_status status;
1139
1140         /*
1141          * Context
1142          * -------
1143          * Attach this 'struct acpi_device' to the ACPI object.  This makes
1144          * resolutions from handle->device very efficient.  Fixed hardware
1145          * devices have no handles, so we skip them.
1146          */
1147         if (!device->handle)
1148                 return 0;
1149
1150         status = acpi_attach_data(device->handle,
1151                                   acpi_bus_data_handler, device);
1152         if (ACPI_SUCCESS(status))
1153                 return 0;
1154
1155         printk(KERN_ERR PREFIX "Error attaching device data\n");
1156         return -ENODEV;
1157 }
1158
1159 static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
1160 {
1161         if (!dev)
1162                 return -EINVAL;
1163
1164         dev->removal_type = ACPI_BUS_REMOVAL_EJECT;
1165         device_release_driver(&dev->dev);
1166
1167         if (!rmdevice)
1168                 return 0;
1169
1170         /*
1171          * unbind _ADR-Based Devices when hot removal
1172          */
1173         if (dev->flags.bus_address) {
1174                 if ((dev->parent) && (dev->parent->ops.unbind))
1175                         dev->parent->ops.unbind(dev);
1176         }
1177         acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
1178
1179         return 0;
1180 }
1181
1182 static int acpi_add_single_object(struct acpi_device **child,
1183                                   acpi_handle handle, int type,
1184                                   unsigned long long sta,
1185                                   struct acpi_bus_ops *ops)
1186 {
1187         int result;
1188         struct acpi_device *device;
1189         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1190
1191         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1192         if (!device) {
1193                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1194                 return -ENOMEM;
1195         }
1196
1197         INIT_LIST_HEAD(&device->pnp.ids);
1198         device->device_type = type;
1199         device->handle = handle;
1200         device->parent = acpi_bus_get_parent(handle);
1201         device->bus_ops = *ops; /* workround for not call .start */
1202         STRUCT_TO_INT(device->status) = sta;
1203
1204         acpi_device_get_busid(device);
1205
1206         /*
1207          * Flags
1208          * -----
1209          * Note that we only look for object handles -- cannot evaluate objects
1210          * until we know the device is present and properly initialized.
1211          */
1212         result = acpi_bus_get_flags(device);
1213         if (result)
1214                 goto end;
1215
1216         /*
1217          * Initialize Device
1218          * -----------------
1219          * TBD: Synch with Core's enumeration/initialization process.
1220          */
1221
1222         /*
1223          * Hardware ID, Unique ID, & Bus Address
1224          * -------------------------------------
1225          */
1226         acpi_device_set_id(device);
1227
1228         /*
1229          * Power Management
1230          * ----------------
1231          */
1232         if (device->flags.power_manageable) {
1233                 result = acpi_bus_get_power_flags(device);
1234                 if (result)
1235                         goto end;
1236         }
1237
1238         /*
1239          * Wakeup device management
1240          *-----------------------
1241          */
1242         if (device->flags.wake_capable) {
1243                 result = acpi_bus_get_wakeup_device_flags(device);
1244                 if (result)
1245                         goto end;
1246         }
1247
1248         /*
1249          * Performance Management
1250          * ----------------------
1251          */
1252         if (device->flags.performance_manageable) {
1253                 result = acpi_bus_get_perf_flags(device);
1254                 if (result)
1255                         goto end;
1256         }
1257
1258         if ((result = acpi_device_set_context(device)))
1259                 goto end;
1260
1261         result = acpi_device_register(device);
1262
1263         /*
1264          * Bind _ADR-Based Devices when hot add
1265          */
1266         if (device->flags.bus_address) {
1267                 if (device->parent && device->parent->ops.bind)
1268                         device->parent->ops.bind(device);
1269         }
1270
1271 end:
1272         if (!result) {
1273                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1274                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1275                         "Adding %s [%s] parent %s\n", dev_name(&device->dev),
1276                          (char *) buffer.pointer,
1277                          device->parent ? dev_name(&device->parent->dev) :
1278                                           "(null)"));
1279                 kfree(buffer.pointer);
1280                 *child = device;
1281         } else
1282                 acpi_device_release(&device->dev);
1283
1284         return result;
1285 }
1286
1287 #define ACPI_STA_DEFAULT (ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED | \
1288                           ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING)
1289
1290 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1291                                     unsigned long long *sta)
1292 {
1293         acpi_status status;
1294         acpi_object_type acpi_type;
1295
1296         status = acpi_get_type(handle, &acpi_type);
1297         if (ACPI_FAILURE(status))
1298                 return -ENODEV;
1299
1300         switch (acpi_type) {
1301         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1302         case ACPI_TYPE_DEVICE:
1303                 *type = ACPI_BUS_TYPE_DEVICE;
1304                 status = acpi_bus_get_status_handle(handle, sta);
1305                 if (ACPI_FAILURE(status))
1306                         return -ENODEV;
1307                 break;
1308         case ACPI_TYPE_PROCESSOR:
1309                 *type = ACPI_BUS_TYPE_PROCESSOR;
1310                 status = acpi_bus_get_status_handle(handle, sta);
1311                 if (ACPI_FAILURE(status))
1312                         return -ENODEV;
1313                 break;
1314         case ACPI_TYPE_THERMAL:
1315                 *type = ACPI_BUS_TYPE_THERMAL;
1316                 *sta = ACPI_STA_DEFAULT;
1317                 break;
1318         case ACPI_TYPE_POWER:
1319                 *type = ACPI_BUS_TYPE_POWER;
1320                 *sta = ACPI_STA_DEFAULT;
1321                 break;
1322         default:
1323                 return -ENODEV;
1324         }
1325
1326         return 0;
1327 }
1328
1329 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl,
1330                                       void *context, void **return_value)
1331 {
1332         struct acpi_bus_ops *ops = context;
1333         int type;
1334         unsigned long long sta;
1335         struct acpi_device *device;
1336         acpi_status status;
1337         int result;
1338
1339         result = acpi_bus_type_and_status(handle, &type, &sta);
1340         if (result)
1341                 return AE_OK;
1342
1343         if (!(sta & ACPI_STA_DEVICE_PRESENT) &&
1344             !(sta & ACPI_STA_DEVICE_FUNCTIONING))
1345                 return AE_CTRL_DEPTH;
1346
1347         /*
1348          * We may already have an acpi_device from a previous enumeration.  If
1349          * so, we needn't add it again, but we may still have to start it.
1350          */
1351         device = NULL;
1352         acpi_bus_get_device(handle, &device);
1353         if (ops->acpi_op_add && !device)
1354                 acpi_add_single_object(&device, handle, type, sta, ops);
1355
1356         if (!device)
1357                 return AE_CTRL_DEPTH;
1358
1359         if (ops->acpi_op_start && !(ops->acpi_op_add)) {
1360                 status = acpi_start_single_object(device);
1361                 if (ACPI_FAILURE(status))
1362                         return AE_CTRL_DEPTH;
1363         }
1364
1365         if (!*return_value)
1366                 *return_value = device;
1367         return AE_OK;
1368 }
1369
1370 static int acpi_bus_scan(acpi_handle handle, struct acpi_bus_ops *ops,
1371                          struct acpi_device **child)
1372 {
1373         acpi_status status;
1374         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1375         void *device = NULL;
1376
1377         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1378         printk(KERN_INFO PREFIX "Enumerating devices from [%s]\n",
1379                (char *) buffer.pointer);
1380
1381         status = acpi_bus_check_add(handle, 0, ops, &device);
1382         if (ACPI_SUCCESS(status))
1383                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1384                                     acpi_bus_check_add, ops, &device);
1385
1386         if (child)
1387                 *child = device;
1388         return 0;
1389 }
1390
1391 int
1392 acpi_bus_add(struct acpi_device **child,
1393              struct acpi_device *parent, acpi_handle handle, int type)
1394 {
1395         struct acpi_bus_ops ops;
1396
1397         memset(&ops, 0, sizeof(ops));
1398         ops.acpi_op_add = 1;
1399
1400         acpi_bus_scan(handle, &ops, child);
1401         return 0;
1402 }
1403 EXPORT_SYMBOL(acpi_bus_add);
1404
1405 int acpi_bus_start(struct acpi_device *device)
1406 {
1407         struct acpi_bus_ops ops;
1408
1409         memset(&ops, 0, sizeof(ops));
1410         ops.acpi_op_start = 1;
1411
1412         acpi_bus_scan(device->handle, &ops, NULL);
1413         return 0;
1414 }
1415 EXPORT_SYMBOL(acpi_bus_start);
1416
1417 int acpi_bus_trim(struct acpi_device *start, int rmdevice)
1418 {
1419         acpi_status status;
1420         struct acpi_device *parent, *child;
1421         acpi_handle phandle, chandle;
1422         acpi_object_type type;
1423         u32 level = 1;
1424         int err = 0;
1425
1426         parent = start;
1427         phandle = start->handle;
1428         child = chandle = NULL;
1429
1430         while ((level > 0) && parent && (!err)) {
1431                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1432                                               chandle, &chandle);
1433
1434                 /*
1435                  * If this scope is exhausted then move our way back up.
1436                  */
1437                 if (ACPI_FAILURE(status)) {
1438                         level--;
1439                         chandle = phandle;
1440                         acpi_get_parent(phandle, &phandle);
1441                         child = parent;
1442                         parent = parent->parent;
1443
1444                         if (level == 0)
1445                                 err = acpi_bus_remove(child, rmdevice);
1446                         else
1447                                 err = acpi_bus_remove(child, 1);
1448
1449                         continue;
1450                 }
1451
1452                 status = acpi_get_type(chandle, &type);
1453                 if (ACPI_FAILURE(status)) {
1454                         continue;
1455                 }
1456                 /*
1457                  * If there is a device corresponding to chandle then
1458                  * parse it (depth-first).
1459                  */
1460                 if (acpi_bus_get_device(chandle, &child) == 0) {
1461                         level++;
1462                         phandle = chandle;
1463                         chandle = NULL;
1464                         parent = child;
1465                 }
1466                 continue;
1467         }
1468         return err;
1469 }
1470 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1471
1472 static int acpi_bus_scan_fixed(void)
1473 {
1474         int result = 0;
1475         struct acpi_device *device = NULL;
1476         struct acpi_bus_ops ops;
1477
1478         memset(&ops, 0, sizeof(ops));
1479         ops.acpi_op_add = 1;
1480         ops.acpi_op_start = 1;
1481
1482         /*
1483          * Enumerate all fixed-feature devices.
1484          */
1485         if ((acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON) == 0) {
1486                 result = acpi_add_single_object(&device, NULL,
1487                                                 ACPI_BUS_TYPE_POWER_BUTTON,
1488                                                 ACPI_STA_DEFAULT,
1489                                                 &ops);
1490         }
1491
1492         if ((acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON) == 0) {
1493                 result = acpi_add_single_object(&device, NULL,
1494                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
1495                                                 ACPI_STA_DEFAULT,
1496                                                 &ops);
1497         }
1498
1499         return result;
1500 }
1501
1502 int __init acpi_scan_init(void)
1503 {
1504         int result;
1505         struct acpi_bus_ops ops;
1506
1507         memset(&ops, 0, sizeof(ops));
1508         ops.acpi_op_add = 1;
1509         ops.acpi_op_start = 1;
1510
1511         result = bus_register(&acpi_bus_type);
1512         if (result) {
1513                 /* We don't want to quit even if we failed to add suspend/resume */
1514                 printk(KERN_ERR PREFIX "Could not register bus type\n");
1515         }
1516
1517         /*
1518          * Enumerate devices in the ACPI namespace.
1519          */
1520         result = acpi_bus_scan(ACPI_ROOT_OBJECT, &ops, &acpi_root);
1521
1522         if (!result)
1523                 result = acpi_bus_scan_fixed();
1524
1525         if (result)
1526                 acpi_device_unregister(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
1527
1528         return result;
1529 }