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/slab.h>
   8 #include <linux/kernel.h>
   9 #include <linux/acpi.h>
  10 #include <linux/signal.h>
  11 #include <linux/kthread.h>
  12 #include <linux/dmi.h>
  13
  14 #include <acpi/acpi_drivers.h>
  15
  16 #include "internal.h"
  17
  18 #define _COMPONENT              ACPI_BUS_COMPONENT
  19 ACPI_MODULE_NAME("scan");
  20 #define STRUCT_TO_INT(s)        (*((int*)&s))
  21 extern struct acpi_device *acpi_root;
  22
  23 #define ACPI_BUS_CLASS                  "system_bus"
  24 #define ACPI_BUS_HID                    "LNXSYBUS"
  25 #define ACPI_BUS_DEVICE_NAME            "System Bus"
  26
  27 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
  28
  29 static const char *dummy_hid = "device";
  30
  31 static LIST_HEAD(acpi_device_list);
  32 static LIST_HEAD(acpi_bus_id_list);
  33 DEFINE_MUTEX(acpi_device_lock);
  34 LIST_HEAD(acpi_wakeup_device_list);
  35
  36 struct acpi_device_bus_id{
  37         char bus_id[15];
  38         unsigned int instance_no;
  39         struct list_head node;
  40 };
  41
  42 /*
  43  * Creates hid/cid(s) string needed for modalias and uevent
  44  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
  45  * char *modalias: "acpi:IBM0001:ACPI0001"
  46 */
  47 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
  48                            int size)
  49 {
  50         int len;
  51         int count;
  52         struct acpi_hardware_id *id;
  53
  54         if (list_empty(&acpi_dev->pnp.ids))
  55                 return 0;
  56
  57         len = snprintf(modalias, size, "acpi:");
  58         size -= len;
  59
  60         list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
  61                 count = snprintf(&modalias[len], size, "%s:", id->id);
  62                 if (count < 0 || count >= size)
  63                         return -EINVAL;
  64                 len += count;
  65                 size -= count;
  66         }
  67
  68         modalias[len] = '\0';
  69         return len;
  70 }
  71
  72 static ssize_t
  73 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
  74         struct acpi_device *acpi_dev = to_acpi_device(dev);
  75         int len;
  76
  77         /* Device has no HID and no CID or string is >1024 */
  78         len = create_modalias(acpi_dev, buf, 1024);
  79         if (len <= 0)
  80                 return 0;
  81         buf[len++] = '\n';
  82         return len;
  83 }
  84 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
  85
  86 static void acpi_bus_hot_remove_device(void *context)
  87 {
  88         struct acpi_device *device;
  89         acpi_handle handle = context;
  90         struct acpi_object_list arg_list;
  91         union acpi_object arg;
  92         acpi_status status = AE_OK;
  93
  94         if (acpi_bus_get_device(handle, &device))
  95                 return;
  96
  97         if (!device)
  98                 return;
  99
 100         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 101                 "Hot-removing device %s...\n", dev_name(&device->dev)));
 102
 103         if (acpi_bus_trim(device, 1)) {
 104                 printk(KERN_ERR PREFIX
 105                                 "Removing device failed\n");
 106                 return;
 107         }
 108
 109         /* power off device */
 110         status = acpi_evaluate_object(handle, "_PS3", NULL, NULL);
 111         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
 112                 printk(KERN_WARNING PREFIX
 113                                 "Power-off device failed\n");
 114
 115         if (device->flags.lockable) {
 116                 arg_list.count = 1;
 117                 arg_list.pointer = &arg;
 118                 arg.type = ACPI_TYPE_INTEGER;
 119                 arg.integer.value = 0;
 120                 acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
 121         }
 122
 123         arg_list.count = 1;
 124         arg_list.pointer = &arg;
 125         arg.type = ACPI_TYPE_INTEGER;
 126         arg.integer.value = 1;
 127
 128         /*
 129          * TBD: _EJD support.
 130          */
 131         status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
 132         if (ACPI_FAILURE(status))
 133                 printk(KERN_WARNING PREFIX
 134                                 "Eject device failed\n");
 135
 136         return;
 137 }
 138
 139 static ssize_t
 140 acpi_eject_store(struct device *d, struct device_attribute *attr,
 141                 const char *buf, size_t count)
 142 {
 143         int ret = count;
 144         acpi_status status;
 145         acpi_object_type type = 0;
 146         struct acpi_device *acpi_device = to_acpi_device(d);
 147
 148         if ((!count) || (buf[0] != '1')) {
 149                 return -EINVAL;
 150         }
 151 #ifndef FORCE_EJECT
 152         if (acpi_device->driver == NULL) {
 153                 ret = -ENODEV;
 154                 goto err;
 155         }
 156 #endif
 157         status = acpi_get_type(acpi_device->handle, &type);
 158         if (ACPI_FAILURE(status) || (!acpi_device->flags.ejectable)) {
 159                 ret = -ENODEV;
 160                 goto err;
 161         }
 162
 163         acpi_os_hotplug_execute(acpi_bus_hot_remove_device, acpi_device->handle);
 164 err:
 165         return ret;
 166 }
 167
 168 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
 169
 170 static ssize_t
 171 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
 172         struct acpi_device *acpi_dev = to_acpi_device(dev);
 173
 174         return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
 175 }
 176 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
 177
 178 static ssize_t
 179 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
 180         struct acpi_device *acpi_dev = to_acpi_device(dev);
 181         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
 182         int result;
 183
 184         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
 185         if (result)
 186                 goto end;
 187
 188         result = sprintf(buf, "%s\n", (char*)path.pointer);
 189         kfree(path.pointer);
 190 end:
 191         return result;
 192 }
 193 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
 194
 195 static int acpi_device_setup_files(struct acpi_device *dev)
 196 {
 197         acpi_status status;
 198         acpi_handle temp;
 199         int result = 0;
 200
 201         /*
 202          * Devices gotten from FADT don't have a "path" attribute
 203          */
 204         if (dev->handle) {
 205                 result = device_create_file(&dev->dev, &dev_attr_path);
 206                 if (result)
 207                         goto end;
 208         }
 209
 210         if (!list_empty(&dev->pnp.ids)) {
 211                 result = device_create_file(&dev->dev, &dev_attr_hid);
 212                 if (result)
 213                         goto end;
 214
 215                 result = device_create_file(&dev->dev, &dev_attr_modalias);
 216                 if (result)
 217                         goto end;
 218         }
 219
 220         /*
 221          * If device has _EJ0, 'eject' file is created that is used to trigger
 222          * hot-removal function from userland.
 223          */
 224         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 225         if (ACPI_SUCCESS(status))
 226                 result = device_create_file(&dev->dev, &dev_attr_eject);
 227 end:
 228         return result;
 229 }
 230
 231 static void acpi_device_remove_files(struct acpi_device *dev)
 232 {
 233         acpi_status status;
 234         acpi_handle temp;
 235
 236         /*
 237          * If device has _EJ0, 'eject' file is created that is used to trigger
 238          * hot-removal function from userland.
 239          */
 240         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
 241         if (ACPI_SUCCESS(status))
 242                 device_remove_file(&dev->dev, &dev_attr_eject);
 243
 244         device_remove_file(&dev->dev, &dev_attr_modalias);
 245         device_remove_file(&dev->dev, &dev_attr_hid);
 246         if (dev->handle)
 247                 device_remove_file(&dev->dev, &dev_attr_path);
 248 }
 249 /* --------------------------------------------------------------------------
 250                         ACPI Bus operations
 251    -------------------------------------------------------------------------- */
 252
 253 int acpi_match_device_ids(struct acpi_device *device,
 254                           const struct acpi_device_id *ids)
 255 {
 256         const struct acpi_device_id *id;
 257         struct acpi_hardware_id *hwid;
 258
 259         /*
 260          * If the device is not present, it is unnecessary to load device
 261          * driver for it.
 262          */
 263         if (!device->status.present)
 264                 return -ENODEV;
 265
 266         for (id = ids; id->id[0]; id++)
 267                 list_for_each_entry(hwid, &device->pnp.ids, list)
 268                         if (!strcmp((char *) id->id, hwid->id))
 269                                 return 0;
 270
 271         return -ENOENT;
 272 }
 273 EXPORT_SYMBOL(acpi_match_device_ids);
 274
 275 static void acpi_free_ids(struct acpi_device *device)
 276 {
 277         struct acpi_hardware_id *id, *tmp;
 278
 279         list_for_each_entry_safe(id, tmp, &device->pnp.ids, list) {
 280                 kfree(id->id);
 281                 kfree(id);
 282         }
 283 }
 284
 285 static void acpi_device_release(struct device *dev)
 286 {
 287         struct acpi_device *acpi_dev = to_acpi_device(dev);
 288
 289         acpi_free_ids(acpi_dev);
 290         kfree(acpi_dev);
 291 }
 292
 293 static int acpi_device_suspend(struct device *dev, pm_message_t state)
 294 {
 295         struct acpi_device *acpi_dev = to_acpi_device(dev);
 296         struct acpi_driver *acpi_drv = acpi_dev->driver;
 297
 298         if (acpi_drv && acpi_drv->ops.suspend)
 299                 return acpi_drv->ops.suspend(acpi_dev, state);
 300         return 0;
 301 }
 302
 303 static int acpi_device_resume(struct device *dev)
 304 {
 305         struct acpi_device *acpi_dev = to_acpi_device(dev);
 306         struct acpi_driver *acpi_drv = acpi_dev->driver;
 307
 308         if (acpi_drv && acpi_drv->ops.resume)
 309                 return acpi_drv->ops.resume(acpi_dev);
 310         return 0;
 311 }
 312
 313 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
 314 {
 315         struct acpi_device *acpi_dev = to_acpi_device(dev);
 316         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
 317
 318         return !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
 319 }
 320
 321 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
 322 {
 323         struct acpi_device *acpi_dev = to_acpi_device(dev);
 324         int len;
 325
 326         if (list_empty(&acpi_dev->pnp.ids))
 327                 return 0;
 328
 329         if (add_uevent_var(env, "MODALIAS="))
 330                 return -ENOMEM;
 331         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
 332                               sizeof(env->buf) - env->buflen);
 333         if (len >= (sizeof(env->buf) - env->buflen))
 334                 return -ENOMEM;
 335         env->buflen += len;
 336         return 0;
 337 }
 338
 339 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
 340 {
 341         struct acpi_device *device = data;
 342
 343         device->driver->ops.notify(device, event);
 344 }
 345
 346 static acpi_status acpi_device_notify_fixed(void *data)
 347 {
 348         struct acpi_device *device = data;
 349
 350         /* Fixed hardware devices have no handles */
 351         acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
 352         return AE_OK;
 353 }
 354
 355 static int acpi_device_install_notify_handler(struct acpi_device *device)
 356 {
 357         acpi_status status;
 358
 359         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 360                 status =
 361                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 362                                                      acpi_device_notify_fixed,
 363                                                      device);
 364         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 365                 status =
 366                     acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 367                                                      acpi_device_notify_fixed,
 368                                                      device);
 369         else
 370                 status = acpi_install_notify_handler(device->handle,
 371                                                      ACPI_DEVICE_NOTIFY,
 372                                                      acpi_device_notify,
 373                                                      device);
 374
 375         if (ACPI_FAILURE(status))
 376                 return -EINVAL;
 377         return 0;
 378 }
 379
 380 static void acpi_device_remove_notify_handler(struct acpi_device *device)
 381 {
 382         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
 383                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
 384                                                 acpi_device_notify_fixed);
 385         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
 386                 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
 387                                                 acpi_device_notify_fixed);
 388         else
 389                 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
 390                                            acpi_device_notify);
 391 }
 392
 393 static int acpi_bus_driver_init(struct acpi_device *, struct acpi_driver *);
 394 static int acpi_start_single_object(struct acpi_device *);
 395 static int acpi_device_probe(struct device * dev)
 396 {
 397         struct acpi_device *acpi_dev = to_acpi_device(dev);
 398         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
 399         int ret;
 400
 401         ret = acpi_bus_driver_init(acpi_dev, acpi_drv);
 402         if (!ret) {
 403                 if (acpi_dev->bus_ops.acpi_op_start)
 404                         acpi_start_single_object(acpi_dev);
 405
 406                 if (acpi_drv->ops.notify) {
 407                         ret = acpi_device_install_notify_handler(acpi_dev);
 408                         if (ret) {
 409                                 if (acpi_drv->ops.remove)
 410                                         acpi_drv->ops.remove(acpi_dev,
 411                                                      acpi_dev->removal_type);
 412                                 return ret;
 413                         }
 414                 }
 415
 416                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 417                         "Found driver [%s] for device [%s]\n",
 418                         acpi_drv->name, acpi_dev->pnp.bus_id));
 419                 get_device(dev);
 420         }
 421         return ret;
 422 }
 423
 424 static int acpi_device_remove(struct device * dev)
 425 {
 426         struct acpi_device *acpi_dev = to_acpi_device(dev);
 427         struct acpi_driver *acpi_drv = acpi_dev->driver;
 428
 429         if (acpi_drv) {
 430                 if (acpi_drv->ops.notify)
 431                         acpi_device_remove_notify_handler(acpi_dev);
 432                 if (acpi_drv->ops.remove)
 433                         acpi_drv->ops.remove(acpi_dev, acpi_dev->removal_type);
 434         }
 435         acpi_dev->driver = NULL;
 436         acpi_dev->driver_data = NULL;
 437
 438         put_device(dev);
 439         return 0;
 440 }
 441
 442 struct bus_type acpi_bus_type = {
 443         .name           = "acpi",
 444         .suspend        = acpi_device_suspend,
 445         .resume         = acpi_device_resume,
 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         return 0;
 519 end:
 520         mutex_lock(&acpi_device_lock);
 521         if (device->parent)
 522                 list_del(&device->node);
 523         list_del(&device->wakeup_list);
 524         mutex_unlock(&acpi_device_lock);
 525         return result;
 526 }
 527
 528 static void acpi_device_unregister(struct acpi_device *device, int type)
 529 {
 530         mutex_lock(&acpi_device_lock);
 531         if (device->parent)
 532                 list_del(&device->node);
 533
 534         list_del(&device->wakeup_list);
 535         mutex_unlock(&acpi_device_lock);
 536
 537         acpi_detach_data(device->handle, acpi_bus_data_handler);
 538
 539         acpi_device_remove_files(device);
 540         device_unregister(&device->dev);
 541 }
 542
 543 /* --------------------------------------------------------------------------
 544                                  Driver Management
 545    -------------------------------------------------------------------------- */
 546 /**
 547  * acpi_bus_driver_init - add a device to a driver
 548  * @device: the device to add and initialize
 549  * @driver: driver for the device
 550  *
 551  * Used to initialize a device via its device driver.  Called whenever a
 552  * driver is bound to a device.  Invokes the driver's add() ops.
 553  */
 554 static int
 555 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
 556 {
 557         int result = 0;
 558
 559         if (!device || !driver)
 560                 return -EINVAL;
 561
 562         if (!driver->ops.add)
 563                 return -ENOSYS;
 564
 565         result = driver->ops.add(device);
 566         if (result) {
 567                 device->driver = NULL;
 568                 device->driver_data = NULL;
 569                 return result;
 570         }
 571
 572         device->driver = driver;
 573
 574         /*
 575          * TBD - Configuration Management: Assign resources to device based
 576          * upon possible configuration and currently allocated resources.
 577          */
 578
 579         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 580                           "Driver successfully bound to device\n"));
 581         return 0;
 582 }
 583
 584 static int acpi_start_single_object(struct acpi_device *device)
 585 {
 586         int result = 0;
 587         struct acpi_driver *driver;
 588
 589
 590         if (!(driver = device->driver))
 591                 return 0;
 592
 593         if (driver->ops.start) {
 594                 result = driver->ops.start(device);
 595                 if (result && driver->ops.remove)
 596                         driver->ops.remove(device, ACPI_BUS_REMOVAL_NORMAL);
 597         }
 598
 599         return result;
 600 }
 601
 602 /**
 603  * acpi_bus_register_driver - register a driver with the ACPI bus
 604  * @driver: driver being registered
 605  *
 606  * Registers a driver with the ACPI bus.  Searches the namespace for all
 607  * devices that match the driver's criteria and binds.  Returns zero for
 608  * success or a negative error status for failure.
 609  */
 610 int acpi_bus_register_driver(struct acpi_driver *driver)
 611 {
 612         int ret;
 613
 614         if (acpi_disabled)
 615                 return -ENODEV;
 616         driver->drv.name = driver->name;
 617         driver->drv.bus = &acpi_bus_type;
 618         driver->drv.owner = driver->owner;
 619
 620         ret = driver_register(&driver->drv);
 621         return ret;
 622 }
 623
 624 EXPORT_SYMBOL(acpi_bus_register_driver);
 625
 626 /**
 627  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
 628  * @driver: driver to unregister
 629  *
 630  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
 631  * devices that match the driver's criteria and unbinds.
 632  */
 633 void acpi_bus_unregister_driver(struct acpi_driver *driver)
 634 {
 635         driver_unregister(&driver->drv);
 636 }
 637
 638 EXPORT_SYMBOL(acpi_bus_unregister_driver);
 639
 640 /* --------------------------------------------------------------------------
 641                                  Device Enumeration
 642    -------------------------------------------------------------------------- */
 643 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
 644 {
 645         acpi_status status;
 646         int ret;
 647         struct acpi_device *device;
 648
 649         /*
 650          * Fixed hardware devices do not appear in the namespace and do not
 651          * have handles, but we fabricate acpi_devices for them, so we have
 652          * to deal with them specially.
 653          */
 654         if (handle == NULL)
 655                 return acpi_root;
 656
 657         do {
 658                 status = acpi_get_parent(handle, &handle);
 659                 if (status == AE_NULL_ENTRY)
 660                         return NULL;
 661                 if (ACPI_FAILURE(status))
 662                         return acpi_root;
 663
 664                 ret = acpi_bus_get_device(handle, &device);
 665                 if (ret == 0)
 666                         return device;
 667         } while (1);
 668 }
 669
 670 acpi_status
 671 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
 672 {
 673         acpi_status status;
 674         acpi_handle tmp;
 675         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 676         union acpi_object *obj;
 677
 678         status = acpi_get_handle(handle, "_EJD", &tmp);
 679         if (ACPI_FAILURE(status))
 680                 return status;
 681
 682         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
 683         if (ACPI_SUCCESS(status)) {
 684                 obj = buffer.pointer;
 685                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
 686                                          ejd);
 687                 kfree(buffer.pointer);
 688         }
 689         return status;
 690 }
 691 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
 692
 693 void acpi_bus_data_handler(acpi_handle handle, void *context)
 694 {
 695
 696         /* TBD */
 697
 698         return;
 699 }
 700
 701 static int acpi_bus_get_perf_flags(struct acpi_device *device)
 702 {
 703         device->performance.state = ACPI_STATE_UNKNOWN;
 704         return 0;
 705 }
 706
 707 static acpi_status
 708 acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
 709                                              struct acpi_device_wakeup *wakeup)
 710 {
 711         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 712         union acpi_object *package = NULL;
 713         union acpi_object *element = NULL;
 714         acpi_status status;
 715         int i = 0;
 716
 717         if (!wakeup)
 718                 return AE_BAD_PARAMETER;
 719
 720         /* _PRW */
 721         status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
 722         if (ACPI_FAILURE(status)) {
 723                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
 724                 return status;
 725         }
 726
 727         package = (union acpi_object *)buffer.pointer;
 728
 729         if (!package || (package->package.count < 2)) {
 730                 status = AE_BAD_DATA;
 731                 goto out;
 732         }
 733
 734         element = &(package->package.elements[0]);
 735         if (!element) {
 736                 status = AE_BAD_DATA;
 737                 goto out;
 738         }
 739         if (element->type == ACPI_TYPE_PACKAGE) {
 740                 if ((element->package.count < 2) ||
 741                     (element->package.elements[0].type !=
 742                      ACPI_TYPE_LOCAL_REFERENCE)
 743                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER)) {
 744                         status = AE_BAD_DATA;
 745                         goto out;
 746                 }
 747                 wakeup->gpe_device =
 748                     element->package.elements[0].reference.handle;
 749                 wakeup->gpe_number =
 750                     (u32) element->package.elements[1].integer.value;
 751         } else if (element->type == ACPI_TYPE_INTEGER) {
 752                 wakeup->gpe_device = NULL;
 753                 wakeup->gpe_number = element->integer.value;
 754         } else {
 755                 status = AE_BAD_DATA;
 756                 goto out;
 757         }
 758
 759         element = &(package->package.elements[1]);
 760         if (element->type != ACPI_TYPE_INTEGER) {
 761                 status = AE_BAD_DATA;
 762                 goto out;
 763         }
 764         wakeup->sleep_state = element->integer.value;
 765
 766         if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
 767                 status = AE_NO_MEMORY;
 768                 goto out;
 769         }
 770         wakeup->resources.count = package->package.count - 2;
 771         for (i = 0; i < wakeup->resources.count; i++) {
 772                 element = &(package->package.elements[i + 2]);
 773                 if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
 774                         status = AE_BAD_DATA;
 775                         goto out;
 776                 }
 777
 778                 wakeup->resources.handles[i] = element->reference.handle;
 779         }
 780
 781         acpi_setup_gpe_for_wake(handle, wakeup->gpe_device, wakeup->gpe_number);
 782
 783  out:
 784         kfree(buffer.pointer);
 785
 786         return status;
 787 }
 788
 789 static void acpi_bus_set_run_wake_flags(struct acpi_device *device)
 790 {
 791         struct acpi_device_id button_device_ids[] = {
 792                 {"PNP0C0D", 0},
 793                 {"PNP0C0C", 0},
 794                 {"PNP0C0E", 0},
 795                 {"", 0},
 796         };
 797         acpi_status status;
 798         acpi_event_status event_status;
 799
 800         device->wakeup.flags.notifier_present = 0;
 801
 802         /* Power button, Lid switch always enable wakeup */
 803         if (!acpi_match_device_ids(device, button_device_ids)) {
 804                 device->wakeup.flags.run_wake = 1;
 805                 device_set_wakeup_capable(&device->dev, true);
 806                 return;
 807         }
 808
 809         status = acpi_get_gpe_status(device->wakeup.gpe_device,
 810                                         device->wakeup.gpe_number,
 811                                                 &event_status);
 812         if (status == AE_OK)
 813                 device->wakeup.flags.run_wake =
 814                                 !!(event_status & ACPI_EVENT_FLAG_HANDLE);
 815 }
 816
 817 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
 818 {
 819         acpi_handle temp;
 820         acpi_status status = 0;
 821         int psw_error;
 822
 823         /* Presence of _PRW indicates wake capable */
 824         status = acpi_get_handle(device->handle, "_PRW", &temp);
 825         if (ACPI_FAILURE(status))
 826                 return;
 827
 828         status = acpi_bus_extract_wakeup_device_power_package(device->handle,
 829                                                               &device->wakeup);
 830         if (ACPI_FAILURE(status)) {
 831                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _PRW package"));
 832                 return;
 833         }
 834
 835         device->wakeup.flags.valid = 1;
 836         device->wakeup.prepare_count = 0;
 837         acpi_bus_set_run_wake_flags(device);
 838         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
 839          * system for the ACPI device with the _PRW object.
 840          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
 841          * So it is necessary to call _DSW object first. Only when it is not
 842          * present will the _PSW object used.
 843          */
 844         psw_error = acpi_device_sleep_wake(device, 0, 0, 0);
 845         if (psw_error)
 846                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 847                                 "error in _DSW or _PSW evaluation\n"));
 848 }
 849
 850 static void acpi_bus_add_power_resource(acpi_handle handle);
 851
 852 static int acpi_bus_get_power_flags(struct acpi_device *device)
 853 {
 854         acpi_status status = 0;
 855         acpi_handle handle = NULL;
 856         u32 i = 0;
 857
 858
 859         /*
 860          * Power Management Flags
 861          */
 862         status = acpi_get_handle(device->handle, "_PSC", &handle);
 863         if (ACPI_SUCCESS(status))
 864                 device->power.flags.explicit_get = 1;
 865         status = acpi_get_handle(device->handle, "_IRC", &handle);
 866         if (ACPI_SUCCESS(status))
 867                 device->power.flags.inrush_current = 1;
 868
 869         /*
 870          * Enumerate supported power management states
 871          */
 872         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
 873                 struct acpi_device_power_state *ps = &device->power.states[i];
 874                 char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
 875
 876                 /* Evaluate "_PRx" to se if power resources are referenced */
 877                 acpi_evaluate_reference(device->handle, object_name, NULL,
 878                                         &ps->resources);
 879                 if (ps->resources.count) {
 880                         int j;
 881
 882                         device->power.flags.power_resources = 1;
 883                         ps->flags.valid = 1;
 884                         for (j = 0; j < ps->resources.count; j++)
 885                                 acpi_bus_add_power_resource(ps->resources.handles[j]);
 886                 }
 887
 888                 /* Evaluate "_PSx" to see if we can do explicit sets */
 889                 object_name[2] = 'S';
 890                 status = acpi_get_handle(device->handle, object_name, &handle);
 891                 if (ACPI_SUCCESS(status)) {
 892                         ps->flags.explicit_set = 1;
 893                         ps->flags.valid = 1;
 894                 }
 895
 896                 /* State is valid if we have some power control */
 897                 if (ps->resources.count || ps->flags.explicit_set)
 898                         ps->flags.valid = 1;
 899
 900                 ps->power = -1; /* Unknown - driver assigned */
 901                 ps->latency = -1;       /* Unknown - driver assigned */
 902         }
 903
 904         /* Set defaults for D0 and D3 states (always valid) */
 905         device->power.states[ACPI_STATE_D0].flags.valid = 1;
 906         device->power.states[ACPI_STATE_D0].power = 100;
 907         device->power.states[ACPI_STATE_D3].flags.valid = 1;
 908         device->power.states[ACPI_STATE_D3].power = 0;
 909
 910         acpi_bus_init_power(device);
 911
 912         return 0;
 913 }
 914
 915 static int acpi_bus_get_flags(struct acpi_device *device)
 916 {
 917         acpi_status status = AE_OK;
 918         acpi_handle temp = NULL;
 919
 920
 921         /* Presence of _STA indicates 'dynamic_status' */
 922         status = acpi_get_handle(device->handle, "_STA", &temp);
 923         if (ACPI_SUCCESS(status))
 924                 device->flags.dynamic_status = 1;
 925
 926         /* Presence of _RMV indicates 'removable' */
 927         status = acpi_get_handle(device->handle, "_RMV", &temp);
 928         if (ACPI_SUCCESS(status))
 929                 device->flags.removable = 1;
 930
 931         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
 932         status = acpi_get_handle(device->handle, "_EJD", &temp);
 933         if (ACPI_SUCCESS(status))
 934                 device->flags.ejectable = 1;
 935         else {
 936                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
 937                 if (ACPI_SUCCESS(status))
 938                         device->flags.ejectable = 1;
 939         }
 940
 941         /* Presence of _LCK indicates 'lockable' */
 942         status = acpi_get_handle(device->handle, "_LCK", &temp);
 943         if (ACPI_SUCCESS(status))
 944                 device->flags.lockable = 1;
 945
 946         /* Power resources cannot be power manageable. */
 947         if (device->device_type == ACPI_BUS_TYPE_POWER)
 948                 return 0;
 949
 950         /* Presence of _PS0|_PR0 indicates 'power manageable' */
 951         status = acpi_get_handle(device->handle, "_PS0", &temp);
 952         if (ACPI_FAILURE(status))
 953                 status = acpi_get_handle(device->handle, "_PR0", &temp);
 954         if (ACPI_SUCCESS(status))
 955                 device->flags.power_manageable = 1;
 956
 957         /* TBD: Performance management */
 958
 959         return 0;
 960 }
 961
 962 static void acpi_device_get_busid(struct acpi_device *device)
 963 {
 964         char bus_id[5] = { '?', 0 };
 965         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
 966         int i = 0;
 967
 968         /*
 969          * Bus ID
 970          * ------
 971          * The device's Bus ID is simply the object name.
 972          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
 973          */
 974         if (ACPI_IS_ROOT_DEVICE(device)) {
 975                 strcpy(device->pnp.bus_id, "ACPI");
 976                 return;
 977         }
 978
 979         switch (device->device_type) {
 980         case ACPI_BUS_TYPE_POWER_BUTTON:
 981                 strcpy(device->pnp.bus_id, "PWRF");
 982                 break;
 983         case ACPI_BUS_TYPE_SLEEP_BUTTON:
 984                 strcpy(device->pnp.bus_id, "SLPF");
 985                 break;
 986         default:
 987                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
 988                 /* Clean up trailing underscores (if any) */
 989                 for (i = 3; i > 1; i--) {
 990                         if (bus_id[i] == '_')
 991                                 bus_id[i] = '\0';
 992                         else
 993                                 break;
 994                 }
 995                 strcpy(device->pnp.bus_id, bus_id);
 996                 break;
 997         }
 998 }
 999
1000 /*
1001  * acpi_bay_match - see if a device is an ejectable driver bay
1002  *
1003  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1004  * then we can safely call it an ejectable drive bay
1005  */
1006 static int acpi_bay_match(struct acpi_device *device){
1007         acpi_status status;
1008         acpi_handle handle;
1009         acpi_handle tmp;
1010         acpi_handle phandle;
1011
1012         handle = device->handle;
1013
1014         status = acpi_get_handle(handle, "_EJ0", &tmp);
1015         if (ACPI_FAILURE(status))
1016                 return -ENODEV;
1017
1018         if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
1019                 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
1020                 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
1021                 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
1022                 return 0;
1023
1024         if (acpi_get_parent(handle, &phandle))
1025                 return -ENODEV;
1026
1027         if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
1028                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
1029                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
1030                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
1031                 return 0;
1032
1033         return -ENODEV;
1034 }
1035
1036 /*
1037  * acpi_dock_match - see if a device has a _DCK method
1038  */
1039 static int acpi_dock_match(struct acpi_device *device)
1040 {
1041         acpi_handle tmp;
1042         return acpi_get_handle(device->handle, "_DCK", &tmp);
1043 }
1044
1045 const char *acpi_device_hid(struct acpi_device *device)
1046 {
1047         struct acpi_hardware_id *hid;
1048
1049         if (list_empty(&device->pnp.ids))
1050                 return dummy_hid;
1051
1052         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1053         return hid->id;
1054 }
1055 EXPORT_SYMBOL(acpi_device_hid);
1056
1057 static void acpi_add_id(struct acpi_device *device, const char *dev_id)
1058 {
1059         struct acpi_hardware_id *id;
1060
1061         id = kmalloc(sizeof(*id), GFP_KERNEL);
1062         if (!id)
1063                 return;
1064
1065         id->id = kmalloc(strlen(dev_id) + 1, GFP_KERNEL);
1066         if (!id->id) {
1067                 kfree(id);
1068                 return;
1069         }
1070
1071         strcpy(id->id, dev_id);
1072         list_add_tail(&id->list, &device->pnp.ids);
1073 }
1074
1075 /*
1076  * Old IBM workstations have a DSDT bug wherein the SMBus object
1077  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1078  * prefix.  Work around this.
1079  */
1080 static int acpi_ibm_smbus_match(struct acpi_device *device)
1081 {
1082         acpi_handle h_dummy;
1083         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
1084         int result;
1085
1086         if (!dmi_name_in_vendors("IBM"))
1087                 return -ENODEV;
1088
1089         /* Look for SMBS object */
1090         result = acpi_get_name(device->handle, ACPI_SINGLE_NAME, &path);
1091         if (result)
1092                 return result;
1093
1094         if (strcmp("SMBS", path.pointer)) {
1095                 result = -ENODEV;
1096                 goto out;
1097         }
1098
1099         /* Does it have the necessary (but misnamed) methods? */
1100         result = -ENODEV;
1101         if (ACPI_SUCCESS(acpi_get_handle(device->handle, "SBI", &h_dummy)) &&
1102             ACPI_SUCCESS(acpi_get_handle(device->handle, "SBR", &h_dummy)) &&
1103             ACPI_SUCCESS(acpi_get_handle(device->handle, "SBW", &h_dummy)))
1104                 result = 0;
1105 out:
1106         kfree(path.pointer);
1107         return result;
1108 }
1109
1110 static void acpi_device_set_id(struct acpi_device *device)
1111 {
1112         acpi_status status;
1113         struct acpi_device_info *info;
1114         struct acpica_device_id_list *cid_list;
1115         int i;
1116
1117         switch (device->device_type) {
1118         case ACPI_BUS_TYPE_DEVICE:
1119                 if (ACPI_IS_ROOT_DEVICE(device)) {
1120                         acpi_add_id(device, ACPI_SYSTEM_HID);
1121                         break;
1122                 }
1123
1124                 status = acpi_get_object_info(device->handle, &info);
1125                 if (ACPI_FAILURE(status)) {
1126                         printk(KERN_ERR PREFIX "%s: Error reading device info\n", __func__);
1127                         return;
1128                 }
1129
1130                 if (info->valid & ACPI_VALID_HID)
1131                         acpi_add_id(device, info->hardware_id.string);
1132                 if (info->valid & ACPI_VALID_CID) {
1133                         cid_list = &info->compatible_id_list;
1134                         for (i = 0; i < cid_list->count; i++)
1135                                 acpi_add_id(device, cid_list->ids[i].string);
1136                 }
1137                 if (info->valid & ACPI_VALID_ADR) {
1138                         device->pnp.bus_address = info->address;
1139                         device->flags.bus_address = 1;
1140                 }
1141
1142                 kfree(info);
1143
1144                 /*
1145                  * Some devices don't reliably have _HIDs & _CIDs, so add
1146                  * synthetic HIDs to make sure drivers can find them.
1147                  */
1148                 if (acpi_is_video_device(device))
1149                         acpi_add_id(device, ACPI_VIDEO_HID);
1150                 else if (ACPI_SUCCESS(acpi_bay_match(device)))
1151                         acpi_add_id(device, ACPI_BAY_HID);
1152                 else if (ACPI_SUCCESS(acpi_dock_match(device)))
1153                         acpi_add_id(device, ACPI_DOCK_HID);
1154                 else if (!acpi_ibm_smbus_match(device))
1155                         acpi_add_id(device, ACPI_SMBUS_IBM_HID);
1156                 else if (!acpi_device_hid(device) &&
1157                          ACPI_IS_ROOT_DEVICE(device->parent)) {
1158                         acpi_add_id(device, ACPI_BUS_HID); /* \_SB, LNXSYBUS */
1159                         strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
1160                         strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
1161                 }
1162
1163                 break;
1164         case ACPI_BUS_TYPE_POWER:
1165                 acpi_add_id(device, ACPI_POWER_HID);
1166                 break;
1167         case ACPI_BUS_TYPE_PROCESSOR:
1168                 acpi_add_id(device, ACPI_PROCESSOR_OBJECT_HID);
1169                 break;
1170         case ACPI_BUS_TYPE_THERMAL:
1171                 acpi_add_id(device, ACPI_THERMAL_HID);
1172                 break;
1173         case ACPI_BUS_TYPE_POWER_BUTTON:
1174                 acpi_add_id(device, ACPI_BUTTON_HID_POWERF);
1175                 break;
1176         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1177                 acpi_add_id(device, ACPI_BUTTON_HID_SLEEPF);
1178                 break;
1179         }
1180 }
1181
1182 static int acpi_device_set_context(struct acpi_device *device)
1183 {
1184         acpi_status status;
1185
1186         /*
1187          * Context
1188          * -------
1189          * Attach this 'struct acpi_device' to the ACPI object.  This makes
1190          * resolutions from handle->device very efficient.  Fixed hardware
1191          * devices have no handles, so we skip them.
1192          */
1193         if (!device->handle)
1194                 return 0;
1195
1196         status = acpi_attach_data(device->handle,
1197                                   acpi_bus_data_handler, device);
1198         if (ACPI_SUCCESS(status))
1199                 return 0;
1200
1201         printk(KERN_ERR PREFIX "Error attaching device data\n");
1202         return -ENODEV;
1203 }
1204
1205 static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
1206 {
1207         if (!dev)
1208                 return -EINVAL;
1209
1210         dev->removal_type = ACPI_BUS_REMOVAL_EJECT;
1211         device_release_driver(&dev->dev);
1212
1213         if (!rmdevice)
1214                 return 0;
1215
1216         /*
1217          * unbind _ADR-Based Devices when hot removal
1218          */
1219         if (dev->flags.bus_address) {
1220                 if ((dev->parent) && (dev->parent->ops.unbind))
1221                         dev->parent->ops.unbind(dev);
1222         }
1223         acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
1224
1225         return 0;
1226 }
1227
1228 static int acpi_add_single_object(struct acpi_device **child,
1229                                   acpi_handle handle, int type,
1230                                   unsigned long long sta,
1231                                   struct acpi_bus_ops *ops)
1232 {
1233         int result;
1234         struct acpi_device *device;
1235         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1236
1237         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1238         if (!device) {
1239                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1240                 return -ENOMEM;
1241         }
1242
1243         INIT_LIST_HEAD(&device->pnp.ids);
1244         device->device_type = type;
1245         device->handle = handle;
1246         device->parent = acpi_bus_get_parent(handle);
1247         device->bus_ops = *ops; /* workround for not call .start */
1248         STRUCT_TO_INT(device->status) = sta;
1249
1250         acpi_device_get_busid(device);
1251
1252         /*
1253          * Flags
1254          * -----
1255          * Note that we only look for object handles -- cannot evaluate objects
1256          * until we know the device is present and properly initialized.
1257          */
1258         result = acpi_bus_get_flags(device);
1259         if (result)
1260                 goto end;
1261
1262         /*
1263          * Initialize Device
1264          * -----------------
1265          * TBD: Synch with Core's enumeration/initialization process.
1266          */
1267         acpi_device_set_id(device);
1268
1269         /*
1270          * Power Management
1271          * ----------------
1272          */
1273         if (device->flags.power_manageable) {
1274                 result = acpi_bus_get_power_flags(device);
1275                 if (result)
1276                         goto end;
1277         }
1278
1279         /*
1280          * Wakeup device management
1281          *-----------------------
1282          */
1283         acpi_bus_get_wakeup_device_flags(device);
1284
1285         /*
1286          * Performance Management
1287          * ----------------------
1288          */
1289         if (device->flags.performance_manageable) {
1290                 result = acpi_bus_get_perf_flags(device);
1291                 if (result)
1292                         goto end;
1293         }
1294
1295         if ((result = acpi_device_set_context(device)))
1296                 goto end;
1297
1298         result = acpi_device_register(device);
1299
1300         /*
1301          * Bind _ADR-Based Devices when hot add
1302          */
1303         if (device->flags.bus_address) {
1304                 if (device->parent && device->parent->ops.bind)
1305                         device->parent->ops.bind(device);
1306         }
1307
1308 end:
1309         if (!result) {
1310                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1311                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1312                         "Adding %s [%s] parent %s\n", dev_name(&device->dev),
1313                          (char *) buffer.pointer,
1314                          device->parent ? dev_name(&device->parent->dev) :
1315                                           "(null)"));
1316                 kfree(buffer.pointer);
1317                 *child = device;
1318         } else
1319                 acpi_device_release(&device->dev);
1320
1321         return result;
1322 }
1323
1324 #define ACPI_STA_DEFAULT (ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED | \
1325                           ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING)
1326
1327 static void acpi_bus_add_power_resource(acpi_handle handle)
1328 {
1329         struct acpi_bus_ops ops = {
1330                 .acpi_op_add = 1,
1331                 .acpi_op_start = 1,
1332         };
1333         struct acpi_device *device = NULL;
1334
1335         acpi_bus_get_device(handle, &device);
1336         if (!device)
1337                 acpi_add_single_object(&device, handle, ACPI_BUS_TYPE_POWER,
1338                                         ACPI_STA_DEFAULT, &ops);
1339 }
1340
1341 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1342                                     unsigned long long *sta)
1343 {
1344         acpi_status status;
1345         acpi_object_type acpi_type;
1346
1347         status = acpi_get_type(handle, &acpi_type);
1348         if (ACPI_FAILURE(status))
1349                 return -ENODEV;
1350
1351         switch (acpi_type) {
1352         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1353         case ACPI_TYPE_DEVICE:
1354                 *type = ACPI_BUS_TYPE_DEVICE;
1355                 status = acpi_bus_get_status_handle(handle, sta);
1356                 if (ACPI_FAILURE(status))
1357                         return -ENODEV;
1358                 break;
1359         case ACPI_TYPE_PROCESSOR:
1360                 *type = ACPI_BUS_TYPE_PROCESSOR;
1361                 status = acpi_bus_get_status_handle(handle, sta);
1362                 if (ACPI_FAILURE(status))
1363                         return -ENODEV;
1364                 break;
1365         case ACPI_TYPE_THERMAL:
1366                 *type = ACPI_BUS_TYPE_THERMAL;
1367                 *sta = ACPI_STA_DEFAULT;
1368                 break;
1369         case ACPI_TYPE_POWER:
1370                 *type = ACPI_BUS_TYPE_POWER;
1371                 *sta = ACPI_STA_DEFAULT;
1372                 break;
1373         default:
1374                 return -ENODEV;
1375         }
1376
1377         return 0;
1378 }
1379
1380 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl,
1381                                       void *context, void **return_value)
1382 {
1383         struct acpi_bus_ops *ops = context;
1384         int type;
1385         unsigned long long sta;
1386         struct acpi_device *device;
1387         acpi_status status;
1388         int result;
1389
1390         result = acpi_bus_type_and_status(handle, &type, &sta);
1391         if (result)
1392                 return AE_OK;
1393
1394         if (!(sta & ACPI_STA_DEVICE_PRESENT) &&
1395             !(sta & ACPI_STA_DEVICE_FUNCTIONING)) {
1396                 struct acpi_device_wakeup wakeup;
1397                 acpi_handle temp;
1398
1399                 status = acpi_get_handle(handle, "_PRW", &temp);
1400                 if (ACPI_SUCCESS(status))
1401                         acpi_bus_extract_wakeup_device_power_package(handle,
1402                                                                      &wakeup);
1403                 return AE_CTRL_DEPTH;
1404         }
1405
1406         /*
1407          * We may already have an acpi_device from a previous enumeration.  If
1408          * so, we needn't add it again, but we may still have to start it.
1409          */
1410         device = NULL;
1411         acpi_bus_get_device(handle, &device);
1412         if (ops->acpi_op_add && !device)
1413                 acpi_add_single_object(&device, handle, type, sta, ops);
1414
1415         if (!device)
1416                 return AE_CTRL_DEPTH;
1417
1418         if (ops->acpi_op_start && !(ops->acpi_op_add)) {
1419                 status = acpi_start_single_object(device);
1420                 if (ACPI_FAILURE(status))
1421                         return AE_CTRL_DEPTH;
1422         }
1423
1424         if (!*return_value)
1425                 *return_value = device;
1426         return AE_OK;
1427 }
1428
1429 static int acpi_bus_scan(acpi_handle handle, struct acpi_bus_ops *ops,
1430                          struct acpi_device **child)
1431 {
1432         acpi_status status;
1433         void *device = NULL;
1434
1435         status = acpi_bus_check_add(handle, 0, ops, &device);
1436         if (ACPI_SUCCESS(status))
1437                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1438                                     acpi_bus_check_add, NULL, ops, &device);
1439
1440         if (child)
1441                 *child = device;
1442
1443         if (device)
1444                 return 0;
1445         else
1446                 return -ENODEV;
1447 }
1448
1449 /*
1450  * acpi_bus_add and acpi_bus_start
1451  *
1452  * scan a given ACPI tree and (probably recently hot-plugged)
1453  * create and add or starts found devices.
1454  *
1455  * If no devices were found -ENODEV is returned which does not
1456  * mean that this is a real error, there just have been no suitable
1457  * ACPI objects in the table trunk from which the kernel could create
1458  * a device and add/start an appropriate driver.
1459  */
1460
1461 int
1462 acpi_bus_add(struct acpi_device **child,
1463              struct acpi_device *parent, acpi_handle handle, int type)
1464 {
1465         struct acpi_bus_ops ops;
1466
1467         memset(&ops, 0, sizeof(ops));
1468         ops.acpi_op_add = 1;
1469
1470         return acpi_bus_scan(handle, &ops, child);
1471 }
1472 EXPORT_SYMBOL(acpi_bus_add);
1473
1474 int acpi_bus_start(struct acpi_device *device)
1475 {
1476         struct acpi_bus_ops ops;
1477         int result;
1478
1479         if (!device)
1480                 return -EINVAL;
1481
1482         memset(&ops, 0, sizeof(ops));
1483         ops.acpi_op_start = 1;
1484
1485         result = acpi_bus_scan(device->handle, &ops, NULL);
1486
1487         acpi_update_all_gpes();
1488
1489         return result;
1490 }
1491 EXPORT_SYMBOL(acpi_bus_start);
1492
1493 int acpi_bus_trim(struct acpi_device *start, int rmdevice)
1494 {
1495         acpi_status status;
1496         struct acpi_device *parent, *child;
1497         acpi_handle phandle, chandle;
1498         acpi_object_type type;
1499         u32 level = 1;
1500         int err = 0;
1501
1502         parent = start;
1503         phandle = start->handle;
1504         child = chandle = NULL;
1505
1506         while ((level > 0) && parent && (!err)) {
1507                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1508                                               chandle, &chandle);
1509
1510                 /*
1511                  * If this scope is exhausted then move our way back up.
1512                  */
1513                 if (ACPI_FAILURE(status)) {
1514                         level--;
1515                         chandle = phandle;
1516                         acpi_get_parent(phandle, &phandle);
1517                         child = parent;
1518                         parent = parent->parent;
1519
1520                         if (level == 0)
1521                                 err = acpi_bus_remove(child, rmdevice);
1522                         else
1523                                 err = acpi_bus_remove(child, 1);
1524
1525                         continue;
1526                 }
1527
1528                 status = acpi_get_type(chandle, &type);
1529                 if (ACPI_FAILURE(status)) {
1530                         continue;
1531                 }
1532                 /*
1533                  * If there is a device corresponding to chandle then
1534                  * parse it (depth-first).
1535                  */
1536                 if (acpi_bus_get_device(chandle, &child) == 0) {
1537                         level++;
1538                         phandle = chandle;
1539                         chandle = NULL;
1540                         parent = child;
1541                 }
1542                 continue;
1543         }
1544         return err;
1545 }
1546 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1547
1548 static int acpi_bus_scan_fixed(void)
1549 {
1550         int result = 0;
1551         struct acpi_device *device = NULL;
1552         struct acpi_bus_ops ops;
1553
1554         memset(&ops, 0, sizeof(ops));
1555         ops.acpi_op_add = 1;
1556         ops.acpi_op_start = 1;
1557
1558         /*
1559          * Enumerate all fixed-feature devices.
1560          */
1561         if ((acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON) == 0) {
1562                 result = acpi_add_single_object(&device, NULL,
1563                                                 ACPI_BUS_TYPE_POWER_BUTTON,
1564                                                 ACPI_STA_DEFAULT,
1565                                                 &ops);
1566         }
1567
1568         if ((acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON) == 0) {
1569                 result = acpi_add_single_object(&device, NULL,
1570                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
1571                                                 ACPI_STA_DEFAULT,
1572                                                 &ops);
1573         }
1574
1575         return result;
1576 }
1577
1578 int __init acpi_scan_init(void)
1579 {
1580         int result;
1581         struct acpi_bus_ops ops;
1582
1583         memset(&ops, 0, sizeof(ops));
1584         ops.acpi_op_add = 1;
1585         ops.acpi_op_start = 1;
1586
1587         result = bus_register(&acpi_bus_type);
1588         if (result) {
1589                 /* We don't want to quit even if we failed to add suspend/resume */
1590                 printk(KERN_ERR PREFIX "Could not register bus type\n");
1591         }
1592
1593         acpi_power_init();
1594
1595         /*
1596          * Enumerate devices in the ACPI namespace.
1597          */
1598         result = acpi_bus_scan(ACPI_ROOT_OBJECT, &ops, &acpi_root);
1599
1600         if (!result)
1601                 result = acpi_bus_scan_fixed();
1602
1603         if (result)
1604                 acpi_device_unregister(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
1605         else
1606                 acpi_update_all_gpes();
1607
1608         return result;
1609 }