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 #include <linux/nls.h>
  14 #include <linux/dma-mapping.h>
  15
  16 #include <asm/pgtable.h>
  17
  18 #include "internal.h"
  19
  20 #define _COMPONENT              ACPI_BUS_COMPONENT
  21 ACPI_MODULE_NAME("scan");
  22 extern struct acpi_device *acpi_root;
  23
  24 #define ACPI_BUS_CLASS                  "system_bus"
  25 #define ACPI_BUS_HID                    "LNXSYBUS"
  26 #define ACPI_BUS_DEVICE_NAME            "System Bus"
  27
  28 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
  29
  30 #define INVALID_ACPI_HANDLE     ((acpi_handle)empty_zero_page)
  31
  32 /*
  33  * If set, devices will be hot-removed even if they cannot be put offline
  34  * gracefully (from the kernel's standpoint).
  35  */
  36 bool acpi_force_hot_remove;
  37
  38 static const char *dummy_hid = "device";
  39
  40 static LIST_HEAD(acpi_dep_list);
  41 static DEFINE_MUTEX(acpi_dep_list_lock);
  42 LIST_HEAD(acpi_bus_id_list);
  43 static DEFINE_MUTEX(acpi_scan_lock);
  44 static LIST_HEAD(acpi_scan_handlers_list);
  45 DEFINE_MUTEX(acpi_device_lock);
  46 LIST_HEAD(acpi_wakeup_device_list);
  47 static DEFINE_MUTEX(acpi_hp_context_lock);
  48
  49 struct acpi_dep_data {
  50         struct list_head node;
  51         acpi_handle master;
  52         acpi_handle slave;
  53 };
  54
  55 void acpi_scan_lock_acquire(void)
  56 {
  57         mutex_lock(&acpi_scan_lock);
  58 }
  59 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
  60
  61 void acpi_scan_lock_release(void)
  62 {
  63         mutex_unlock(&acpi_scan_lock);
  64 }
  65 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
  66
  67 void acpi_lock_hp_context(void)
  68 {
  69         mutex_lock(&acpi_hp_context_lock);
  70 }
  71
  72 void acpi_unlock_hp_context(void)
  73 {
  74         mutex_unlock(&acpi_hp_context_lock);
  75 }
  76
  77 void acpi_initialize_hp_context(struct acpi_device *adev,
  78                                 struct acpi_hotplug_context *hp,
  79                                 int (*notify)(struct acpi_device *, u32),
  80                                 void (*uevent)(struct acpi_device *, u32))
  81 {
  82         acpi_lock_hp_context();
  83         hp->notify = notify;
  84         hp->uevent = uevent;
  85         acpi_set_hp_context(adev, hp);
  86         acpi_unlock_hp_context();
  87 }
  88 EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
  89
  90 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
  91 {
  92         if (!handler)
  93                 return -EINVAL;
  94
  95         list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
  96         return 0;
  97 }
  98
  99 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
 100                                        const char *hotplug_profile_name)
 101 {
 102         int error;
 103
 104         error = acpi_scan_add_handler(handler);
 105         if (error)
 106                 return error;
 107
 108         acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
 109         return 0;
 110 }
 111
 112 bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
 113 {
 114         struct acpi_device_physical_node *pn;
 115         bool offline = true;
 116
 117         /*
 118          * acpi_container_offline() calls this for all of the container's
 119          * children under the container's physical_node_lock lock.
 120          */
 121         mutex_lock_nested(&adev->physical_node_lock, SINGLE_DEPTH_NESTING);
 122
 123         list_for_each_entry(pn, &adev->physical_node_list, node)
 124                 if (device_supports_offline(pn->dev) && !pn->dev->offline) {
 125                         if (uevent)
 126                                 kobject_uevent(&pn->dev->kobj, KOBJ_CHANGE);
 127
 128                         offline = false;
 129                         break;
 130                 }
 131
 132         mutex_unlock(&adev->physical_node_lock);
 133         return offline;
 134 }
 135
 136 static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
 137                                     void **ret_p)
 138 {
 139         struct acpi_device *device = NULL;
 140         struct acpi_device_physical_node *pn;
 141         bool second_pass = (bool)data;
 142         acpi_status status = AE_OK;
 143
 144         if (acpi_bus_get_device(handle, &device))
 145                 return AE_OK;
 146
 147         if (device->handler && !device->handler->hotplug.enabled) {
 148                 *ret_p = &device->dev;
 149                 return AE_SUPPORT;
 150         }
 151
 152         mutex_lock(&device->physical_node_lock);
 153
 154         list_for_each_entry(pn, &device->physical_node_list, node) {
 155                 int ret;
 156
 157                 if (second_pass) {
 158                         /* Skip devices offlined by the first pass. */
 159                         if (pn->put_online)
 160                                 continue;
 161                 } else {
 162                         pn->put_online = false;
 163                 }
 164                 ret = device_offline(pn->dev);
 165                 if (acpi_force_hot_remove)
 166                         continue;
 167
 168                 if (ret >= 0) {
 169                         pn->put_online = !ret;
 170                 } else {
 171                         *ret_p = pn->dev;
 172                         if (second_pass) {
 173                                 status = AE_ERROR;
 174                                 break;
 175                         }
 176                 }
 177         }
 178
 179         mutex_unlock(&device->physical_node_lock);
 180
 181         return status;
 182 }
 183
 184 static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
 185                                    void **ret_p)
 186 {
 187         struct acpi_device *device = NULL;
 188         struct acpi_device_physical_node *pn;
 189
 190         if (acpi_bus_get_device(handle, &device))
 191                 return AE_OK;
 192
 193         mutex_lock(&device->physical_node_lock);
 194
 195         list_for_each_entry(pn, &device->physical_node_list, node)
 196                 if (pn->put_online) {
 197                         device_online(pn->dev);
 198                         pn->put_online = false;
 199                 }
 200
 201         mutex_unlock(&device->physical_node_lock);
 202
 203         return AE_OK;
 204 }
 205
 206 static int acpi_scan_try_to_offline(struct acpi_device *device)
 207 {
 208         acpi_handle handle = device->handle;
 209         struct device *errdev = NULL;
 210         acpi_status status;
 211
 212         /*
 213          * Carry out two passes here and ignore errors in the first pass,
 214          * because if the devices in question are memory blocks and
 215          * CONFIG_MEMCG is set, one of the blocks may hold data structures
 216          * that the other blocks depend on, but it is not known in advance which
 217          * block holds them.
 218          *
 219          * If the first pass is successful, the second one isn't needed, though.
 220          */
 221         status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 222                                      NULL, acpi_bus_offline, (void *)false,
 223                                      (void **)&errdev);
 224         if (status == AE_SUPPORT) {
 225                 dev_warn(errdev, "Offline disabled.\n");
 226                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 227                                     acpi_bus_online, NULL, NULL, NULL);
 228                 return -EPERM;
 229         }
 230         acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
 231         if (errdev) {
 232                 errdev = NULL;
 233                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 234                                     NULL, acpi_bus_offline, (void *)true,
 235                                     (void **)&errdev);
 236                 if (!errdev || acpi_force_hot_remove)
 237                         acpi_bus_offline(handle, 0, (void *)true,
 238                                          (void **)&errdev);
 239
 240                 if (errdev && !acpi_force_hot_remove) {
 241                         dev_warn(errdev, "Offline failed.\n");
 242                         acpi_bus_online(handle, 0, NULL, NULL);
 243                         acpi_walk_namespace(ACPI_TYPE_ANY, handle,
 244                                             ACPI_UINT32_MAX, acpi_bus_online,
 245                                             NULL, NULL, NULL);
 246                         return -EBUSY;
 247                 }
 248         }
 249         return 0;
 250 }
 251
 252 static int acpi_scan_hot_remove(struct acpi_device *device)
 253 {
 254         acpi_handle handle = device->handle;
 255         unsigned long long sta;
 256         acpi_status status;
 257
 258         if (device->handler && device->handler->hotplug.demand_offline
 259             && !acpi_force_hot_remove) {
 260                 if (!acpi_scan_is_offline(device, true))
 261                         return -EBUSY;
 262         } else {
 263                 int error = acpi_scan_try_to_offline(device);
 264                 if (error)
 265                         return error;
 266         }
 267
 268         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 269                 "Hot-removing device %s...\n", dev_name(&device->dev)));
 270
 271         acpi_bus_trim(device);
 272
 273         acpi_evaluate_lck(handle, 0);
 274         /*
 275          * TBD: _EJD support.
 276          */
 277         status = acpi_evaluate_ej0(handle);
 278         if (status == AE_NOT_FOUND)
 279                 return -ENODEV;
 280         else if (ACPI_FAILURE(status))
 281                 return -EIO;
 282
 283         /*
 284          * Verify if eject was indeed successful.  If not, log an error
 285          * message.  No need to call _OST since _EJ0 call was made OK.
 286          */
 287         status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
 288         if (ACPI_FAILURE(status)) {
 289                 acpi_handle_warn(handle,
 290                         "Status check after eject failed (0x%x)\n", status);
 291         } else if (sta & ACPI_STA_DEVICE_ENABLED) {
 292                 acpi_handle_warn(handle,
 293                         "Eject incomplete - status 0x%llx\n", sta);
 294         }
 295
 296         return 0;
 297 }
 298
 299 static int acpi_scan_device_not_present(struct acpi_device *adev)
 300 {
 301         if (!acpi_device_enumerated(adev)) {
 302                 dev_warn(&adev->dev, "Still not present\n");
 303                 return -EALREADY;
 304         }
 305         acpi_bus_trim(adev);
 306         return 0;
 307 }
 308
 309 static int acpi_scan_device_check(struct acpi_device *adev)
 310 {
 311         int error;
 312
 313         acpi_bus_get_status(adev);
 314         if (adev->status.present || adev->status.functional) {
 315                 /*
 316                  * This function is only called for device objects for which
 317                  * matching scan handlers exist.  The only situation in which
 318                  * the scan handler is not attached to this device object yet
 319                  * is when the device has just appeared (either it wasn't
 320                  * present at all before or it was removed and then added
 321                  * again).
 322                  */
 323                 if (adev->handler) {
 324                         dev_warn(&adev->dev, "Already enumerated\n");
 325                         return -EALREADY;
 326                 }
 327                 error = acpi_bus_scan(adev->handle);
 328                 if (error) {
 329                         dev_warn(&adev->dev, "Namespace scan failure\n");
 330                         return error;
 331                 }
 332                 if (!adev->handler) {
 333                         dev_warn(&adev->dev, "Enumeration failure\n");
 334                         error = -ENODEV;
 335                 }
 336         } else {
 337                 error = acpi_scan_device_not_present(adev);
 338         }
 339         return error;
 340 }
 341
 342 static int acpi_scan_bus_check(struct acpi_device *adev)
 343 {
 344         struct acpi_scan_handler *handler = adev->handler;
 345         struct acpi_device *child;
 346         int error;
 347
 348         acpi_bus_get_status(adev);
 349         if (!(adev->status.present || adev->status.functional)) {
 350                 acpi_scan_device_not_present(adev);
 351                 return 0;
 352         }
 353         if (handler && handler->hotplug.scan_dependent)
 354                 return handler->hotplug.scan_dependent(adev);
 355
 356         error = acpi_bus_scan(adev->handle);
 357         if (error) {
 358                 dev_warn(&adev->dev, "Namespace scan failure\n");
 359                 return error;
 360         }
 361         list_for_each_entry(child, &adev->children, node) {
 362                 error = acpi_scan_bus_check(child);
 363                 if (error)
 364                         return error;
 365         }
 366         return 0;
 367 }
 368
 369 static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type)
 370 {
 371         switch (type) {
 372         case ACPI_NOTIFY_BUS_CHECK:
 373                 return acpi_scan_bus_check(adev);
 374         case ACPI_NOTIFY_DEVICE_CHECK:
 375                 return acpi_scan_device_check(adev);
 376         case ACPI_NOTIFY_EJECT_REQUEST:
 377         case ACPI_OST_EC_OSPM_EJECT:
 378                 if (adev->handler && !adev->handler->hotplug.enabled) {
 379                         dev_info(&adev->dev, "Eject disabled\n");
 380                         return -EPERM;
 381                 }
 382                 acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST,
 383                                   ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
 384                 return acpi_scan_hot_remove(adev);
 385         }
 386         return -EINVAL;
 387 }
 388
 389 void acpi_device_hotplug(struct acpi_device *adev, u32 src)
 390 {
 391         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
 392         int error = -ENODEV;
 393
 394         lock_device_hotplug();
 395         mutex_lock(&acpi_scan_lock);
 396
 397         /*
 398          * The device object's ACPI handle cannot become invalid as long as we
 399          * are holding acpi_scan_lock, but it might have become invalid before
 400          * that lock was acquired.
 401          */
 402         if (adev->handle == INVALID_ACPI_HANDLE)
 403                 goto err_out;
 404
 405         if (adev->flags.is_dock_station) {
 406                 error = dock_notify(adev, src);
 407         } else if (adev->flags.hotplug_notify) {
 408                 error = acpi_generic_hotplug_event(adev, src);
 409                 if (error == -EPERM) {
 410                         ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
 411                         goto err_out;
 412                 }
 413         } else {
 414                 int (*notify)(struct acpi_device *, u32);
 415
 416                 acpi_lock_hp_context();
 417                 notify = adev->hp ? adev->hp->notify : NULL;
 418                 acpi_unlock_hp_context();
 419                 /*
 420                  * There may be additional notify handlers for device objects
 421                  * without the .event() callback, so ignore them here.
 422                  */
 423                 if (notify)
 424                         error = notify(adev, src);
 425                 else
 426                         goto out;
 427         }
 428         if (!error)
 429                 ost_code = ACPI_OST_SC_SUCCESS;
 430
 431  err_out:
 432         acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
 433
 434  out:
 435         acpi_bus_put_acpi_device(adev);
 436         mutex_unlock(&acpi_scan_lock);
 437         unlock_device_hotplug();
 438 }
 439
 440 static void acpi_free_power_resources_lists(struct acpi_device *device)
 441 {
 442         int i;
 443
 444         if (device->wakeup.flags.valid)
 445                 acpi_power_resources_list_free(&device->wakeup.resources);
 446
 447         if (!device->power.flags.power_resources)
 448                 return;
 449
 450         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
 451                 struct acpi_device_power_state *ps = &device->power.states[i];
 452                 acpi_power_resources_list_free(&ps->resources);
 453         }
 454 }
 455
 456 static void acpi_device_release(struct device *dev)
 457 {
 458         struct acpi_device *acpi_dev = to_acpi_device(dev);
 459
 460         acpi_free_properties(acpi_dev);
 461         acpi_free_pnp_ids(&acpi_dev->pnp);
 462         acpi_free_power_resources_lists(acpi_dev);
 463         kfree(acpi_dev);
 464 }
 465
 466 static void acpi_device_del(struct acpi_device *device)
 467 {
 468         struct acpi_device_bus_id *acpi_device_bus_id;
 469
 470         mutex_lock(&acpi_device_lock);
 471         if (device->parent)
 472                 list_del(&device->node);
 473
 474         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node)
 475                 if (!strcmp(acpi_device_bus_id->bus_id,
 476                             acpi_device_hid(device))) {
 477                         if (acpi_device_bus_id->instance_no > 0)
 478                                 acpi_device_bus_id->instance_no--;
 479                         else {
 480                                 list_del(&acpi_device_bus_id->node);
 481                                 kfree(acpi_device_bus_id);
 482                         }
 483                         break;
 484                 }
 485
 486         list_del(&device->wakeup_list);
 487         mutex_unlock(&acpi_device_lock);
 488
 489         acpi_power_add_remove_device(device, false);
 490         acpi_device_remove_files(device);
 491         if (device->remove)
 492                 device->remove(device);
 493
 494         device_del(&device->dev);
 495 }
 496
 497 static BLOCKING_NOTIFIER_HEAD(acpi_reconfig_chain);
 498
 499 static LIST_HEAD(acpi_device_del_list);
 500 static DEFINE_MUTEX(acpi_device_del_lock);
 501
 502 static void acpi_device_del_work_fn(struct work_struct *work_not_used)
 503 {
 504         for (;;) {
 505                 struct acpi_device *adev;
 506
 507                 mutex_lock(&acpi_device_del_lock);
 508
 509                 if (list_empty(&acpi_device_del_list)) {
 510                         mutex_unlock(&acpi_device_del_lock);
 511                         break;
 512                 }
 513                 adev = list_first_entry(&acpi_device_del_list,
 514                                         struct acpi_device, del_list);
 515                 list_del(&adev->del_list);
 516
 517                 mutex_unlock(&acpi_device_del_lock);
 518
 519                 blocking_notifier_call_chain(&acpi_reconfig_chain,
 520                                              ACPI_RECONFIG_DEVICE_REMOVE, adev);
 521
 522                 acpi_device_del(adev);
 523                 /*
 524                  * Drop references to all power resources that might have been
 525                  * used by the device.
 526                  */
 527                 acpi_power_transition(adev, ACPI_STATE_D3_COLD);
 528                 put_device(&adev->dev);
 529         }
 530 }
 531
 532 /**
 533  * acpi_scan_drop_device - Drop an ACPI device object.
 534  * @handle: Handle of an ACPI namespace node, not used.
 535  * @context: Address of the ACPI device object to drop.
 536  *
 537  * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
 538  * namespace node the device object pointed to by @context is attached to.
 539  *
 540  * The unregistration is carried out asynchronously to avoid running
 541  * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
 542  * ensure the correct ordering (the device objects must be unregistered in the
 543  * same order in which the corresponding namespace nodes are deleted).
 544  */
 545 static void acpi_scan_drop_device(acpi_handle handle, void *context)
 546 {
 547         static DECLARE_WORK(work, acpi_device_del_work_fn);
 548         struct acpi_device *adev = context;
 549
 550         mutex_lock(&acpi_device_del_lock);
 551
 552         /*
 553          * Use the ACPI hotplug workqueue which is ordered, so this work item
 554          * won't run after any hotplug work items submitted subsequently.  That
 555          * prevents attempts to register device objects identical to those being
 556          * deleted from happening concurrently (such attempts result from
 557          * hotplug events handled via the ACPI hotplug workqueue).  It also will
 558          * run after all of the work items submitted previosuly, which helps
 559          * those work items to ensure that they are not accessing stale device
 560          * objects.
 561          */
 562         if (list_empty(&acpi_device_del_list))
 563                 acpi_queue_hotplug_work(&work);
 564
 565         list_add_tail(&adev->del_list, &acpi_device_del_list);
 566         /* Make acpi_ns_validate_handle() return NULL for this handle. */
 567         adev->handle = INVALID_ACPI_HANDLE;
 568
 569         mutex_unlock(&acpi_device_del_lock);
 570 }
 571
 572 static int acpi_get_device_data(acpi_handle handle, struct acpi_device **device,
 573                                 void (*callback)(void *))
 574 {
 575         acpi_status status;
 576
 577         if (!device)
 578                 return -EINVAL;
 579
 580         status = acpi_get_data_full(handle, acpi_scan_drop_device,
 581                                     (void **)device, callback);
 582         if (ACPI_FAILURE(status) || !*device) {
 583                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
 584                                   handle));
 585                 return -ENODEV;
 586         }
 587         return 0;
 588 }
 589
 590 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
 591 {
 592         return acpi_get_device_data(handle, device, NULL);
 593 }
 594 EXPORT_SYMBOL(acpi_bus_get_device);
 595
 596 static void get_acpi_device(void *dev)
 597 {
 598         if (dev)
 599                 get_device(&((struct acpi_device *)dev)->dev);
 600 }
 601
 602 struct acpi_device *acpi_bus_get_acpi_device(acpi_handle handle)
 603 {
 604         struct acpi_device *adev = NULL;
 605
 606         acpi_get_device_data(handle, &adev, get_acpi_device);
 607         return adev;
 608 }
 609
 610 void acpi_bus_put_acpi_device(struct acpi_device *adev)
 611 {
 612         put_device(&adev->dev);
 613 }
 614
 615 int acpi_device_add(struct acpi_device *device,
 616                     void (*release)(struct device *))
 617 {
 618         int result;
 619         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
 620         int found = 0;
 621
 622         if (device->handle) {
 623                 acpi_status status;
 624
 625                 status = acpi_attach_data(device->handle, acpi_scan_drop_device,
 626                                           device);
 627                 if (ACPI_FAILURE(status)) {
 628                         acpi_handle_err(device->handle,
 629                                         "Unable to attach device data\n");
 630                         return -ENODEV;
 631                 }
 632         }
 633
 634         /*
 635          * Linkage
 636          * -------
 637          * Link this device to its parent and siblings.
 638          */
 639         INIT_LIST_HEAD(&device->children);
 640         INIT_LIST_HEAD(&device->node);
 641         INIT_LIST_HEAD(&device->wakeup_list);
 642         INIT_LIST_HEAD(&device->physical_node_list);
 643         INIT_LIST_HEAD(&device->del_list);
 644         mutex_init(&device->physical_node_lock);
 645
 646         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
 647         if (!new_bus_id) {
 648                 pr_err(PREFIX "Memory allocation error\n");
 649                 result = -ENOMEM;
 650                 goto err_detach;
 651         }
 652
 653         mutex_lock(&acpi_device_lock);
 654         /*
 655          * Find suitable bus_id and instance number in acpi_bus_id_list
 656          * If failed, create one and link it into acpi_bus_id_list
 657          */
 658         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
 659                 if (!strcmp(acpi_device_bus_id->bus_id,
 660                             acpi_device_hid(device))) {
 661                         acpi_device_bus_id->instance_no++;
 662                         found = 1;
 663                         kfree(new_bus_id);
 664                         break;
 665                 }
 666         }
 667         if (!found) {
 668                 acpi_device_bus_id = new_bus_id;
 669                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
 670                 acpi_device_bus_id->instance_no = 0;
 671                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
 672         }
 673         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
 674
 675         if (device->parent)
 676                 list_add_tail(&device->node, &device->parent->children);
 677
 678         if (device->wakeup.flags.valid)
 679                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
 680         mutex_unlock(&acpi_device_lock);
 681
 682         if (device->parent)
 683                 device->dev.parent = &device->parent->dev;
 684         device->dev.bus = &acpi_bus_type;
 685         device->dev.release = release;
 686         result = device_add(&device->dev);
 687         if (result) {
 688                 dev_err(&device->dev, "Error registering device\n");
 689                 goto err;
 690         }
 691
 692         result = acpi_device_setup_files(device);
 693         if (result)
 694                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
 695                        dev_name(&device->dev));
 696
 697         return 0;
 698
 699  err:
 700         mutex_lock(&acpi_device_lock);
 701         if (device->parent)
 702                 list_del(&device->node);
 703         list_del(&device->wakeup_list);
 704         mutex_unlock(&acpi_device_lock);
 705
 706  err_detach:
 707         acpi_detach_data(device->handle, acpi_scan_drop_device);
 708         return result;
 709 }
 710
 711 /* --------------------------------------------------------------------------
 712                                  Device Enumeration
 713    -------------------------------------------------------------------------- */
 714 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
 715 {
 716         struct acpi_device *device = NULL;
 717         acpi_status status;
 718
 719         /*
 720          * Fixed hardware devices do not appear in the namespace and do not
 721          * have handles, but we fabricate acpi_devices for them, so we have
 722          * to deal with them specially.
 723          */
 724         if (!handle)
 725                 return acpi_root;
 726
 727         do {
 728                 status = acpi_get_parent(handle, &handle);
 729                 if (ACPI_FAILURE(status))
 730                         return status == AE_NULL_ENTRY ? NULL : acpi_root;
 731         } while (acpi_bus_get_device(handle, &device));
 732         return device;
 733 }
 734
 735 acpi_status
 736 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
 737 {
 738         acpi_status status;
 739         acpi_handle tmp;
 740         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 741         union acpi_object *obj;
 742
 743         status = acpi_get_handle(handle, "_EJD", &tmp);
 744         if (ACPI_FAILURE(status))
 745                 return status;
 746
 747         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
 748         if (ACPI_SUCCESS(status)) {
 749                 obj = buffer.pointer;
 750                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
 751                                          ejd);
 752                 kfree(buffer.pointer);
 753         }
 754         return status;
 755 }
 756 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
 757
 758 static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
 759                                         struct acpi_device_wakeup *wakeup)
 760 {
 761         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 762         union acpi_object *package = NULL;
 763         union acpi_object *element = NULL;
 764         acpi_status status;
 765         int err = -ENODATA;
 766
 767         if (!wakeup)
 768                 return -EINVAL;
 769
 770         INIT_LIST_HEAD(&wakeup->resources);
 771
 772         /* _PRW */
 773         status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
 774         if (ACPI_FAILURE(status)) {
 775                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
 776                 return err;
 777         }
 778
 779         package = (union acpi_object *)buffer.pointer;
 780
 781         if (!package || package->package.count < 2)
 782                 goto out;
 783
 784         element = &(package->package.elements[0]);
 785         if (!element)
 786                 goto out;
 787
 788         if (element->type == ACPI_TYPE_PACKAGE) {
 789                 if ((element->package.count < 2) ||
 790                     (element->package.elements[0].type !=
 791                      ACPI_TYPE_LOCAL_REFERENCE)
 792                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
 793                         goto out;
 794
 795                 wakeup->gpe_device =
 796                     element->package.elements[0].reference.handle;
 797                 wakeup->gpe_number =
 798                     (u32) element->package.elements[1].integer.value;
 799         } else if (element->type == ACPI_TYPE_INTEGER) {
 800                 wakeup->gpe_device = NULL;
 801                 wakeup->gpe_number = element->integer.value;
 802         } else {
 803                 goto out;
 804         }
 805
 806         element = &(package->package.elements[1]);
 807         if (element->type != ACPI_TYPE_INTEGER)
 808                 goto out;
 809
 810         wakeup->sleep_state = element->integer.value;
 811
 812         err = acpi_extract_power_resources(package, 2, &wakeup->resources);
 813         if (err)
 814                 goto out;
 815
 816         if (!list_empty(&wakeup->resources)) {
 817                 int sleep_state;
 818
 819                 err = acpi_power_wakeup_list_init(&wakeup->resources,
 820                                                   &sleep_state);
 821                 if (err) {
 822                         acpi_handle_warn(handle, "Retrieving current states "
 823                                          "of wakeup power resources failed\n");
 824                         acpi_power_resources_list_free(&wakeup->resources);
 825                         goto out;
 826                 }
 827                 if (sleep_state < wakeup->sleep_state) {
 828                         acpi_handle_warn(handle, "Overriding _PRW sleep state "
 829                                          "(S%d) by S%d from power resources\n",
 830                                          (int)wakeup->sleep_state, sleep_state);
 831                         wakeup->sleep_state = sleep_state;
 832                 }
 833         }
 834
 835  out:
 836         kfree(buffer.pointer);
 837         return err;
 838 }
 839
 840 static void acpi_wakeup_gpe_init(struct acpi_device *device)
 841 {
 842         static const struct acpi_device_id button_device_ids[] = {
 843                 {"PNP0C0C", 0},
 844                 {"PNP0C0D", 0},
 845                 {"PNP0C0E", 0},
 846                 {"", 0},
 847         };
 848         struct acpi_device_wakeup *wakeup = &device->wakeup;
 849         acpi_status status;
 850         acpi_event_status event_status;
 851
 852         wakeup->flags.notifier_present = 0;
 853
 854         /* Power button, Lid switch always enable wakeup */
 855         if (!acpi_match_device_ids(device, button_device_ids)) {
 856                 wakeup->flags.run_wake = 1;
 857                 if (!acpi_match_device_ids(device, &button_device_ids[1])) {
 858                         /* Do not use Lid/sleep button for S5 wakeup */
 859                         if (wakeup->sleep_state == ACPI_STATE_S5)
 860                                 wakeup->sleep_state = ACPI_STATE_S4;
 861                 }
 862                 acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
 863                 device_set_wakeup_capable(&device->dev, true);
 864                 return;
 865         }
 866
 867         acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
 868                                 wakeup->gpe_number);
 869         status = acpi_get_gpe_status(wakeup->gpe_device, wakeup->gpe_number,
 870                                      &event_status);
 871         if (ACPI_FAILURE(status))
 872                 return;
 873
 874         wakeup->flags.run_wake = !!(event_status & ACPI_EVENT_FLAG_HAS_HANDLER);
 875 }
 876
 877 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
 878 {
 879         int err;
 880
 881         /* Presence of _PRW indicates wake capable */
 882         if (!acpi_has_method(device->handle, "_PRW"))
 883                 return;
 884
 885         err = acpi_bus_extract_wakeup_device_power_package(device->handle,
 886                                                            &device->wakeup);
 887         if (err) {
 888                 dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
 889                 return;
 890         }
 891
 892         device->wakeup.flags.valid = 1;
 893         device->wakeup.prepare_count = 0;
 894         acpi_wakeup_gpe_init(device);
 895         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
 896          * system for the ACPI device with the _PRW object.
 897          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
 898          * So it is necessary to call _DSW object first. Only when it is not
 899          * present will the _PSW object used.
 900          */
 901         err = acpi_device_sleep_wake(device, 0, 0, 0);
 902         if (err)
 903                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 904                                 "error in _DSW or _PSW evaluation\n"));
 905 }
 906
 907 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
 908 {
 909         struct acpi_device_power_state *ps = &device->power.states[state];
 910         char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
 911         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 912         acpi_status status;
 913
 914         INIT_LIST_HEAD(&ps->resources);
 915
 916         /* Evaluate "_PRx" to get referenced power resources */
 917         status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
 918         if (ACPI_SUCCESS(status)) {
 919                 union acpi_object *package = buffer.pointer;
 920
 921                 if (buffer.length && package
 922                     && package->type == ACPI_TYPE_PACKAGE
 923                     && package->package.count) {
 924                         int err = acpi_extract_power_resources(package, 0,
 925                                                                &ps->resources);
 926                         if (!err)
 927                                 device->power.flags.power_resources = 1;
 928                 }
 929                 ACPI_FREE(buffer.pointer);
 930         }
 931
 932         /* Evaluate "_PSx" to see if we can do explicit sets */
 933         pathname[2] = 'S';
 934         if (acpi_has_method(device->handle, pathname))
 935                 ps->flags.explicit_set = 1;
 936
 937         /* State is valid if there are means to put the device into it. */
 938         if (!list_empty(&ps->resources) || ps->flags.explicit_set)
 939                 ps->flags.valid = 1;
 940
 941         ps->power = -1;         /* Unknown - driver assigned */
 942         ps->latency = -1;       /* Unknown - driver assigned */
 943 }
 944
 945 static void acpi_bus_get_power_flags(struct acpi_device *device)
 946 {
 947         u32 i;
 948
 949         /* Presence of _PS0|_PR0 indicates 'power manageable' */
 950         if (!acpi_has_method(device->handle, "_PS0") &&
 951             !acpi_has_method(device->handle, "_PR0"))
 952                 return;
 953
 954         device->flags.power_manageable = 1;
 955
 956         /*
 957          * Power Management Flags
 958          */
 959         if (acpi_has_method(device->handle, "_PSC"))
 960                 device->power.flags.explicit_get = 1;
 961
 962         if (acpi_has_method(device->handle, "_IRC"))
 963                 device->power.flags.inrush_current = 1;
 964
 965         if (acpi_has_method(device->handle, "_DSW"))
 966                 device->power.flags.dsw_present = 1;
 967
 968         /*
 969          * Enumerate supported power management states
 970          */
 971         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
 972                 acpi_bus_init_power_state(device, i);
 973
 974         INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
 975         if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources))
 976                 device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
 977
 978         /* Set defaults for D0 and D3hot states (always valid) */
 979         device->power.states[ACPI_STATE_D0].flags.valid = 1;
 980         device->power.states[ACPI_STATE_D0].power = 100;
 981         device->power.states[ACPI_STATE_D3_HOT].flags.valid = 1;
 982
 983         if (acpi_bus_init_power(device))
 984                 device->flags.power_manageable = 0;
 985 }
 986
 987 static void acpi_bus_get_flags(struct acpi_device *device)
 988 {
 989         /* Presence of _STA indicates 'dynamic_status' */
 990         if (acpi_has_method(device->handle, "_STA"))
 991                 device->flags.dynamic_status = 1;
 992
 993         /* Presence of _RMV indicates 'removable' */
 994         if (acpi_has_method(device->handle, "_RMV"))
 995                 device->flags.removable = 1;
 996
 997         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
 998         if (acpi_has_method(device->handle, "_EJD") ||
 999             acpi_has_method(device->handle, "_EJ0"))
1000                 device->flags.ejectable = 1;
1001 }
1002
1003 static void acpi_device_get_busid(struct acpi_device *device)
1004 {
1005         char bus_id[5] = { '?', 0 };
1006         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1007         int i = 0;
1008
1009         /*
1010          * Bus ID
1011          * ------
1012          * The device's Bus ID is simply the object name.
1013          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1014          */
1015         if (ACPI_IS_ROOT_DEVICE(device)) {
1016                 strcpy(device->pnp.bus_id, "ACPI");
1017                 return;
1018         }
1019
1020         switch (device->device_type) {
1021         case ACPI_BUS_TYPE_POWER_BUTTON:
1022                 strcpy(device->pnp.bus_id, "PWRF");
1023                 break;
1024         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1025                 strcpy(device->pnp.bus_id, "SLPF");
1026                 break;
1027         default:
1028                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1029                 /* Clean up trailing underscores (if any) */
1030                 for (i = 3; i > 1; i--) {
1031                         if (bus_id[i] == '_')
1032                                 bus_id[i] = '\0';
1033                         else
1034                                 break;
1035                 }
1036                 strcpy(device->pnp.bus_id, bus_id);
1037                 break;
1038         }
1039 }
1040
1041 /*
1042  * acpi_ata_match - see if an acpi object is an ATA device
1043  *
1044  * If an acpi object has one of the ACPI ATA methods defined,
1045  * then we can safely call it an ATA device.
1046  */
1047 bool acpi_ata_match(acpi_handle handle)
1048 {
1049         return acpi_has_method(handle, "_GTF") ||
1050                acpi_has_method(handle, "_GTM") ||
1051                acpi_has_method(handle, "_STM") ||
1052                acpi_has_method(handle, "_SDD");
1053 }
1054
1055 /*
1056  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1057  *
1058  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1059  * then we can safely call it an ejectable drive bay
1060  */
1061 bool acpi_bay_match(acpi_handle handle)
1062 {
1063         acpi_handle phandle;
1064
1065         if (!acpi_has_method(handle, "_EJ0"))
1066                 return false;
1067         if (acpi_ata_match(handle))
1068                 return true;
1069         if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1070                 return false;
1071
1072         return acpi_ata_match(phandle);
1073 }
1074
1075 bool acpi_device_is_battery(struct acpi_device *adev)
1076 {
1077         struct acpi_hardware_id *hwid;
1078
1079         list_for_each_entry(hwid, &adev->pnp.ids, list)
1080                 if (!strcmp("PNP0C0A", hwid->id))
1081                         return true;
1082
1083         return false;
1084 }
1085
1086 static bool is_ejectable_bay(struct acpi_device *adev)
1087 {
1088         acpi_handle handle = adev->handle;
1089
1090         if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
1091                 return true;
1092
1093         return acpi_bay_match(handle);
1094 }
1095
1096 /*
1097  * acpi_dock_match - see if an acpi object has a _DCK method
1098  */
1099 bool acpi_dock_match(acpi_handle handle)
1100 {
1101         return acpi_has_method(handle, "_DCK");
1102 }
1103
1104 static acpi_status
1105 acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
1106                           void **return_value)
1107 {
1108         long *cap = context;
1109
1110         if (acpi_has_method(handle, "_BCM") &&
1111             acpi_has_method(handle, "_BCL")) {
1112                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight "
1113                                   "support\n"));
1114                 *cap |= ACPI_VIDEO_BACKLIGHT;
1115                 if (!acpi_has_method(handle, "_BQC"))
1116                         printk(KERN_WARNING FW_BUG PREFIX "No _BQC method, "
1117                                 "cannot determine initial brightness\n");
1118                 /* We have backlight support, no need to scan further */
1119                 return AE_CTRL_TERMINATE;
1120         }
1121         return 0;
1122 }
1123
1124 /* Returns true if the ACPI object is a video device which can be
1125  * handled by video.ko.
1126  * The device will get a Linux specific CID added in scan.c to
1127  * identify the device as an ACPI graphics device
1128  * Be aware that the graphics device may not be physically present
1129  * Use acpi_video_get_capabilities() to detect general ACPI video
1130  * capabilities of present cards
1131  */
1132 long acpi_is_video_device(acpi_handle handle)
1133 {
1134         long video_caps = 0;
1135
1136         /* Is this device able to support video switching ? */
1137         if (acpi_has_method(handle, "_DOD") || acpi_has_method(handle, "_DOS"))
1138                 video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
1139
1140         /* Is this device able to retrieve a video ROM ? */
1141         if (acpi_has_method(handle, "_ROM"))
1142                 video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
1143
1144         /* Is this device able to configure which video head to be POSTed ? */
1145         if (acpi_has_method(handle, "_VPO") &&
1146             acpi_has_method(handle, "_GPD") &&
1147             acpi_has_method(handle, "_SPD"))
1148                 video_caps |= ACPI_VIDEO_DEVICE_POSTING;
1149
1150         /* Only check for backlight functionality if one of the above hit. */
1151         if (video_caps)
1152                 acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
1153                                     ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
1154                                     &video_caps, NULL);
1155
1156         return video_caps;
1157 }
1158 EXPORT_SYMBOL(acpi_is_video_device);
1159
1160 const char *acpi_device_hid(struct acpi_device *device)
1161 {
1162         struct acpi_hardware_id *hid;
1163
1164         if (list_empty(&device->pnp.ids))
1165                 return dummy_hid;
1166
1167         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1168         return hid->id;
1169 }
1170 EXPORT_SYMBOL(acpi_device_hid);
1171
1172 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1173 {
1174         struct acpi_hardware_id *id;
1175
1176         id = kmalloc(sizeof(*id), GFP_KERNEL);
1177         if (!id)
1178                 return;
1179
1180         id->id = kstrdup_const(dev_id, GFP_KERNEL);
1181         if (!id->id) {
1182                 kfree(id);
1183                 return;
1184         }
1185
1186         list_add_tail(&id->list, &pnp->ids);
1187         pnp->type.hardware_id = 1;
1188 }
1189
1190 /*
1191  * Old IBM workstations have a DSDT bug wherein the SMBus object
1192  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1193  * prefix.  Work around this.
1194  */
1195 static bool acpi_ibm_smbus_match(acpi_handle handle)
1196 {
1197         char node_name[ACPI_PATH_SEGMENT_LENGTH];
1198         struct acpi_buffer path = { sizeof(node_name), node_name };
1199
1200         if (!dmi_name_in_vendors("IBM"))
1201                 return false;
1202
1203         /* Look for SMBS object */
1204         if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1205             strcmp("SMBS", path.pointer))
1206                 return false;
1207
1208         /* Does it have the necessary (but misnamed) methods? */
1209         if (acpi_has_method(handle, "SBI") &&
1210             acpi_has_method(handle, "SBR") &&
1211             acpi_has_method(handle, "SBW"))
1212                 return true;
1213
1214         return false;
1215 }
1216
1217 static bool acpi_object_is_system_bus(acpi_handle handle)
1218 {
1219         acpi_handle tmp;
1220
1221         if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
1222             tmp == handle)
1223                 return true;
1224         if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
1225             tmp == handle)
1226                 return true;
1227
1228         return false;
1229 }
1230
1231 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1232                                 int device_type)
1233 {
1234         acpi_status status;
1235         struct acpi_device_info *info;
1236         struct acpi_pnp_device_id_list *cid_list;
1237         int i;
1238
1239         switch (device_type) {
1240         case ACPI_BUS_TYPE_DEVICE:
1241                 if (handle == ACPI_ROOT_OBJECT) {
1242                         acpi_add_id(pnp, ACPI_SYSTEM_HID);
1243                         break;
1244                 }
1245
1246                 status = acpi_get_object_info(handle, &info);
1247                 if (ACPI_FAILURE(status)) {
1248                         pr_err(PREFIX "%s: Error reading device info\n",
1249                                         __func__);
1250                         return;
1251                 }
1252
1253                 if (info->valid & ACPI_VALID_HID) {
1254                         acpi_add_id(pnp, info->hardware_id.string);
1255                         pnp->type.platform_id = 1;
1256                 }
1257                 if (info->valid & ACPI_VALID_CID) {
1258                         cid_list = &info->compatible_id_list;
1259                         for (i = 0; i < cid_list->count; i++)
1260                                 acpi_add_id(pnp, cid_list->ids[i].string);
1261                 }
1262                 if (info->valid & ACPI_VALID_ADR) {
1263                         pnp->bus_address = info->address;
1264                         pnp->type.bus_address = 1;
1265                 }
1266                 if (info->valid & ACPI_VALID_UID)
1267                         pnp->unique_id = kstrdup(info->unique_id.string,
1268                                                         GFP_KERNEL);
1269                 if (info->valid & ACPI_VALID_CLS)
1270                         acpi_add_id(pnp, info->class_code.string);
1271
1272                 kfree(info);
1273
1274                 /*
1275                  * Some devices don't reliably have _HIDs & _CIDs, so add
1276                  * synthetic HIDs to make sure drivers can find them.
1277                  */
1278                 if (acpi_is_video_device(handle))
1279                         acpi_add_id(pnp, ACPI_VIDEO_HID);
1280                 else if (acpi_bay_match(handle))
1281                         acpi_add_id(pnp, ACPI_BAY_HID);
1282                 else if (acpi_dock_match(handle))
1283                         acpi_add_id(pnp, ACPI_DOCK_HID);
1284                 else if (acpi_ibm_smbus_match(handle))
1285                         acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1286                 else if (list_empty(&pnp->ids) &&
1287                          acpi_object_is_system_bus(handle)) {
1288                         /* \_SB, \_TZ, LNXSYBUS */
1289                         acpi_add_id(pnp, ACPI_BUS_HID);
1290                         strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1291                         strcpy(pnp->device_class, ACPI_BUS_CLASS);
1292                 }
1293
1294                 break;
1295         case ACPI_BUS_TYPE_POWER:
1296                 acpi_add_id(pnp, ACPI_POWER_HID);
1297                 break;
1298         case ACPI_BUS_TYPE_PROCESSOR:
1299                 acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1300                 break;
1301         case ACPI_BUS_TYPE_THERMAL:
1302                 acpi_add_id(pnp, ACPI_THERMAL_HID);
1303                 break;
1304         case ACPI_BUS_TYPE_POWER_BUTTON:
1305                 acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1306                 break;
1307         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1308                 acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1309                 break;
1310         }
1311 }
1312
1313 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1314 {
1315         struct acpi_hardware_id *id, *tmp;
1316
1317         list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1318                 kfree_const(id->id);
1319                 kfree(id);
1320         }
1321         kfree(pnp->unique_id);
1322 }
1323
1324 /**
1325  * acpi_dma_supported - Check DMA support for the specified device.
1326  * @adev: The pointer to acpi device
1327  *
1328  * Return false if DMA is not supported. Otherwise, return true
1329  */
1330 bool acpi_dma_supported(struct acpi_device *adev)
1331 {
1332         if (!adev)
1333                 return false;
1334
1335         if (adev->flags.cca_seen)
1336                 return true;
1337
1338         /*
1339         * Per ACPI 6.0 sec 6.2.17, assume devices can do cache-coherent
1340         * DMA on "Intel platforms".  Presumably that includes all x86 and
1341         * ia64, and other arches will set CONFIG_ACPI_CCA_REQUIRED=y.
1342         */
1343         if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1344                 return true;
1345
1346         return false;
1347 }
1348
1349 /**
1350  * acpi_get_dma_attr - Check the supported DMA attr for the specified device.
1351  * @adev: The pointer to acpi device
1352  *
1353  * Return enum dev_dma_attr.
1354  */
1355 enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
1356 {
1357         if (!acpi_dma_supported(adev))
1358                 return DEV_DMA_NOT_SUPPORTED;
1359
1360         if (adev->flags.coherent_dma)
1361                 return DEV_DMA_COHERENT;
1362         else
1363                 return DEV_DMA_NON_COHERENT;
1364 }
1365
1366 static void acpi_init_coherency(struct acpi_device *adev)
1367 {
1368         unsigned long long cca = 0;
1369         acpi_status status;
1370         struct acpi_device *parent = adev->parent;
1371
1372         if (parent && parent->flags.cca_seen) {
1373                 /*
1374                  * From ACPI spec, OSPM will ignore _CCA if an ancestor
1375                  * already saw one.
1376                  */
1377                 adev->flags.cca_seen = 1;
1378                 cca = parent->flags.coherent_dma;
1379         } else {
1380                 status = acpi_evaluate_integer(adev->handle, "_CCA",
1381                                                NULL, &cca);
1382                 if (ACPI_SUCCESS(status))
1383                         adev->flags.cca_seen = 1;
1384                 else if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1385                         /*
1386                          * If architecture does not specify that _CCA is
1387                          * required for DMA-able devices (e.g. x86),
1388                          * we default to _CCA=1.
1389                          */
1390                         cca = 1;
1391                 else
1392                         acpi_handle_debug(adev->handle,
1393                                           "ACPI device is missing _CCA.\n");
1394         }
1395
1396         adev->flags.coherent_dma = cca;
1397 }
1398
1399 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1400                              int type, unsigned long long sta)
1401 {
1402         INIT_LIST_HEAD(&device->pnp.ids);
1403         device->device_type = type;
1404         device->handle = handle;
1405         device->parent = acpi_bus_get_parent(handle);
1406         device->fwnode.type = FWNODE_ACPI;
1407         acpi_set_device_status(device, sta);
1408         acpi_device_get_busid(device);
1409         acpi_set_pnp_ids(handle, &device->pnp, type);
1410         acpi_init_properties(device);
1411         acpi_bus_get_flags(device);
1412         device->flags.match_driver = false;
1413         device->flags.initialized = true;
1414         acpi_device_clear_enumerated(device);
1415         device_initialize(&device->dev);
1416         dev_set_uevent_suppress(&device->dev, true);
1417         acpi_init_coherency(device);
1418 }
1419
1420 void acpi_device_add_finalize(struct acpi_device *device)
1421 {
1422         dev_set_uevent_suppress(&device->dev, false);
1423         kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1424 }
1425
1426 static int acpi_add_single_object(struct acpi_device **child,
1427                                   acpi_handle handle, int type,
1428                                   unsigned long long sta)
1429 {
1430         int result;
1431         struct acpi_device *device;
1432         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1433
1434         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1435         if (!device) {
1436                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1437                 return -ENOMEM;
1438         }
1439
1440         acpi_init_device_object(device, handle, type, sta);
1441         acpi_bus_get_power_flags(device);
1442         acpi_bus_get_wakeup_device_flags(device);
1443
1444         result = acpi_device_add(device, acpi_device_release);
1445         if (result) {
1446                 acpi_device_release(&device->dev);
1447                 return result;
1448         }
1449
1450         acpi_power_add_remove_device(device, true);
1451         acpi_device_add_finalize(device);
1452         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1453         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1454                 dev_name(&device->dev), (char *) buffer.pointer,
1455                 device->parent ? dev_name(&device->parent->dev) : "(null)"));
1456         kfree(buffer.pointer);
1457         *child = device;
1458         return 0;
1459 }
1460
1461 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1462                                     unsigned long long *sta)
1463 {
1464         acpi_status status;
1465         acpi_object_type acpi_type;
1466
1467         status = acpi_get_type(handle, &acpi_type);
1468         if (ACPI_FAILURE(status))
1469                 return -ENODEV;
1470
1471         switch (acpi_type) {
1472         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1473         case ACPI_TYPE_DEVICE:
1474                 *type = ACPI_BUS_TYPE_DEVICE;
1475                 status = acpi_bus_get_status_handle(handle, sta);
1476                 if (ACPI_FAILURE(status))
1477                         *sta = 0;
1478                 break;
1479         case ACPI_TYPE_PROCESSOR:
1480                 *type = ACPI_BUS_TYPE_PROCESSOR;
1481                 status = acpi_bus_get_status_handle(handle, sta);
1482                 if (ACPI_FAILURE(status))
1483                         return -ENODEV;
1484                 break;
1485         case ACPI_TYPE_THERMAL:
1486                 *type = ACPI_BUS_TYPE_THERMAL;
1487                 *sta = ACPI_STA_DEFAULT;
1488                 break;
1489         case ACPI_TYPE_POWER:
1490                 *type = ACPI_BUS_TYPE_POWER;
1491                 *sta = ACPI_STA_DEFAULT;
1492                 break;
1493         default:
1494                 return -ENODEV;
1495         }
1496
1497         return 0;
1498 }
1499
1500 bool acpi_device_is_present(struct acpi_device *adev)
1501 {
1502         if (adev->status.present || adev->status.functional)
1503                 return true;
1504
1505         adev->flags.initialized = false;
1506         return false;
1507 }
1508
1509 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1510                                        const char *idstr,
1511                                        const struct acpi_device_id **matchid)
1512 {
1513         const struct acpi_device_id *devid;
1514
1515         if (handler->match)
1516                 return handler->match(idstr, matchid);
1517
1518         for (devid = handler->ids; devid->id[0]; devid++)
1519                 if (!strcmp((char *)devid->id, idstr)) {
1520                         if (matchid)
1521                                 *matchid = devid;
1522
1523                         return true;
1524                 }
1525
1526         return false;
1527 }
1528
1529 static struct acpi_scan_handler *acpi_scan_match_handler(const char *idstr,
1530                                         const struct acpi_device_id **matchid)
1531 {
1532         struct acpi_scan_handler *handler;
1533
1534         list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1535                 if (acpi_scan_handler_matching(handler, idstr, matchid))
1536                         return handler;
1537
1538         return NULL;
1539 }
1540
1541 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1542 {
1543         if (!!hotplug->enabled == !!val)
1544                 return;
1545
1546         mutex_lock(&acpi_scan_lock);
1547
1548         hotplug->enabled = val;
1549
1550         mutex_unlock(&acpi_scan_lock);
1551 }
1552
1553 static void acpi_scan_init_hotplug(struct acpi_device *adev)
1554 {
1555         struct acpi_hardware_id *hwid;
1556
1557         if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
1558                 acpi_dock_add(adev);
1559                 return;
1560         }
1561         list_for_each_entry(hwid, &adev->pnp.ids, list) {
1562                 struct acpi_scan_handler *handler;
1563
1564                 handler = acpi_scan_match_handler(hwid->id, NULL);
1565                 if (handler) {
1566                         adev->flags.hotplug_notify = true;
1567                         break;
1568                 }
1569         }
1570 }
1571
1572 static void acpi_device_dep_initialize(struct acpi_device *adev)
1573 {
1574         struct acpi_dep_data *dep;
1575         struct acpi_handle_list dep_devices;
1576         acpi_status status;
1577         int i;
1578
1579         if (!acpi_has_method(adev->handle, "_DEP"))
1580                 return;
1581
1582         status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
1583                                         &dep_devices);
1584         if (ACPI_FAILURE(status)) {
1585                 dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
1586                 return;
1587         }
1588
1589         for (i = 0; i < dep_devices.count; i++) {
1590                 struct acpi_device_info *info;
1591                 int skip;
1592
1593                 status = acpi_get_object_info(dep_devices.handles[i], &info);
1594                 if (ACPI_FAILURE(status)) {
1595                         dev_dbg(&adev->dev, "Error reading _DEP device info\n");
1596                         continue;
1597                 }
1598
1599                 /*
1600                  * Skip the dependency of Windows System Power
1601                  * Management Controller
1602                  */
1603                 skip = info->valid & ACPI_VALID_HID &&
1604                         !strcmp(info->hardware_id.string, "INT3396");
1605
1606                 kfree(info);
1607
1608                 if (skip)
1609                         continue;
1610
1611                 dep = kzalloc(sizeof(struct acpi_dep_data), GFP_KERNEL);
1612                 if (!dep)
1613                         return;
1614
1615                 dep->master = dep_devices.handles[i];
1616                 dep->slave  = adev->handle;
1617                 adev->dep_unmet++;
1618
1619                 mutex_lock(&acpi_dep_list_lock);
1620                 list_add_tail(&dep->node , &acpi_dep_list);
1621                 mutex_unlock(&acpi_dep_list_lock);
1622         }
1623 }
1624
1625 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
1626                                       void *not_used, void **return_value)
1627 {
1628         struct acpi_device *device = NULL;
1629         int type;
1630         unsigned long long sta;
1631         int result;
1632
1633         acpi_bus_get_device(handle, &device);
1634         if (device)
1635                 goto out;
1636
1637         result = acpi_bus_type_and_status(handle, &type, &sta);
1638         if (result)
1639                 return AE_OK;
1640
1641         if (type == ACPI_BUS_TYPE_POWER) {
1642                 acpi_add_power_resource(handle);
1643                 return AE_OK;
1644         }
1645
1646         acpi_add_single_object(&device, handle, type, sta);
1647         if (!device)
1648                 return AE_CTRL_DEPTH;
1649
1650         acpi_scan_init_hotplug(device);
1651         acpi_device_dep_initialize(device);
1652
1653  out:
1654         if (!*return_value)
1655                 *return_value = device;
1656
1657         return AE_OK;
1658 }
1659
1660 static int acpi_check_spi_i2c_slave(struct acpi_resource *ares, void *data)
1661 {
1662         bool *is_spi_i2c_slave_p = data;
1663
1664         if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
1665                 return 1;
1666
1667         /*
1668          * devices that are connected to UART still need to be enumerated to
1669          * platform bus
1670          */
1671         if (ares->data.common_serial_bus.type != ACPI_RESOURCE_SERIAL_TYPE_UART)
1672                 *is_spi_i2c_slave_p = true;
1673
1674          /* no need to do more checking */
1675         return -1;
1676 }
1677
1678 static void acpi_default_enumeration(struct acpi_device *device)
1679 {
1680         struct list_head resource_list;
1681         bool is_spi_i2c_slave = false;
1682
1683         /*
1684          * Do not enumerate SPI/I2C slaves as they will be enumerated by their
1685          * respective parents.
1686          */
1687         INIT_LIST_HEAD(&resource_list);
1688         acpi_dev_get_resources(device, &resource_list, acpi_check_spi_i2c_slave,
1689                                &is_spi_i2c_slave);
1690         acpi_dev_free_resource_list(&resource_list);
1691         if (!is_spi_i2c_slave) {
1692                 acpi_create_platform_device(device);
1693                 acpi_device_set_enumerated(device);
1694         } else {
1695                 blocking_notifier_call_chain(&acpi_reconfig_chain,
1696                                              ACPI_RECONFIG_DEVICE_ADD, device);
1697         }
1698 }
1699
1700 static const struct acpi_device_id generic_device_ids[] = {
1701         {ACPI_DT_NAMESPACE_HID, },
1702         {"", },
1703 };
1704
1705 static int acpi_generic_device_attach(struct acpi_device *adev,
1706                                       const struct acpi_device_id *not_used)
1707 {
1708         /*
1709          * Since ACPI_DT_NAMESPACE_HID is the only ID handled here, the test
1710          * below can be unconditional.
1711          */
1712         if (adev->data.of_compatible)
1713                 acpi_default_enumeration(adev);
1714
1715         return 1;
1716 }
1717
1718 static struct acpi_scan_handler generic_device_handler = {
1719         .ids = generic_device_ids,
1720         .attach = acpi_generic_device_attach,
1721 };
1722
1723 static int acpi_scan_attach_handler(struct acpi_device *device)
1724 {
1725         struct acpi_hardware_id *hwid;
1726         int ret = 0;
1727
1728         list_for_each_entry(hwid, &device->pnp.ids, list) {
1729                 const struct acpi_device_id *devid;
1730                 struct acpi_scan_handler *handler;
1731
1732                 handler = acpi_scan_match_handler(hwid->id, &devid);
1733                 if (handler) {
1734                         if (!handler->attach) {
1735                                 device->pnp.type.platform_id = 0;
1736                                 continue;
1737                         }
1738                         device->handler = handler;
1739                         ret = handler->attach(device, devid);
1740                         if (ret > 0)
1741                                 break;
1742
1743                         device->handler = NULL;
1744                         if (ret < 0)
1745                                 break;
1746                 }
1747         }
1748
1749         return ret;
1750 }
1751
1752 static void acpi_bus_attach(struct acpi_device *device)
1753 {
1754         struct acpi_device *child;
1755         acpi_handle ejd;
1756         int ret;
1757
1758         if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
1759                 register_dock_dependent_device(device, ejd);
1760
1761         acpi_bus_get_status(device);
1762         /* Skip devices that are not present. */
1763         if (!acpi_device_is_present(device)) {
1764                 acpi_device_clear_enumerated(device);
1765                 device->flags.power_manageable = 0;
1766                 return;
1767         }
1768         if (device->handler)
1769                 goto ok;
1770
1771         if (!device->flags.initialized) {
1772                 device->flags.power_manageable =
1773                         device->power.states[ACPI_STATE_D0].flags.valid;
1774                 if (acpi_bus_init_power(device))
1775                         device->flags.power_manageable = 0;
1776
1777                 device->flags.initialized = true;
1778         }
1779
1780         ret = acpi_scan_attach_handler(device);
1781         if (ret < 0)
1782                 return;
1783
1784         device->flags.match_driver = true;
1785         if (!ret) {
1786                 ret = device_attach(&device->dev);
1787                 if (ret < 0)
1788                         return;
1789
1790                 if (!ret && device->pnp.type.platform_id)
1791                         acpi_default_enumeration(device);
1792         }
1793
1794  ok:
1795         list_for_each_entry(child, &device->children, node)
1796                 acpi_bus_attach(child);
1797
1798         if (device->handler && device->handler->hotplug.notify_online)
1799                 device->handler->hotplug.notify_online(device);
1800 }
1801
1802 void acpi_walk_dep_device_list(acpi_handle handle)
1803 {
1804         struct acpi_dep_data *dep, *tmp;
1805         struct acpi_device *adev;
1806
1807         mutex_lock(&acpi_dep_list_lock);
1808         list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
1809                 if (dep->master == handle) {
1810                         acpi_bus_get_device(dep->slave, &adev);
1811                         if (!adev)
1812                                 continue;
1813
1814                         adev->dep_unmet--;
1815                         if (!adev->dep_unmet)
1816                                 acpi_bus_attach(adev);
1817                         list_del(&dep->node);
1818                         kfree(dep);
1819                 }
1820         }
1821         mutex_unlock(&acpi_dep_list_lock);
1822 }
1823 EXPORT_SYMBOL_GPL(acpi_walk_dep_device_list);
1824
1825 /**
1826  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
1827  * @handle: Root of the namespace scope to scan.
1828  *
1829  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
1830  * found devices.
1831  *
1832  * If no devices were found, -ENODEV is returned, but it does not mean that
1833  * there has been a real error.  There just have been no suitable ACPI objects
1834  * in the table trunk from which the kernel could create a device and add an
1835  * appropriate driver.
1836  *
1837  * Must be called under acpi_scan_lock.
1838  */
1839 int acpi_bus_scan(acpi_handle handle)
1840 {
1841         void *device = NULL;
1842
1843         if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
1844                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1845                                     acpi_bus_check_add, NULL, NULL, &device);
1846
1847         if (device) {
1848                 acpi_bus_attach(device);
1849                 return 0;
1850         }
1851         return -ENODEV;
1852 }
1853 EXPORT_SYMBOL(acpi_bus_scan);
1854
1855 /**
1856  * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
1857  * @adev: Root of the ACPI namespace scope to walk.
1858  *
1859  * Must be called under acpi_scan_lock.
1860  */
1861 void acpi_bus_trim(struct acpi_device *adev)
1862 {
1863         struct acpi_scan_handler *handler = adev->handler;
1864         struct acpi_device *child;
1865
1866         list_for_each_entry_reverse(child, &adev->children, node)
1867                 acpi_bus_trim(child);
1868
1869         adev->flags.match_driver = false;
1870         if (handler) {
1871                 if (handler->detach)
1872                         handler->detach(adev);
1873
1874                 adev->handler = NULL;
1875         } else {
1876                 device_release_driver(&adev->dev);
1877         }
1878         /*
1879          * Most likely, the device is going away, so put it into D3cold before
1880          * that.
1881          */
1882         acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
1883         adev->flags.initialized = false;
1884         acpi_device_clear_enumerated(adev);
1885 }
1886 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1887
1888 static int acpi_bus_scan_fixed(void)
1889 {
1890         int result = 0;
1891
1892         /*
1893          * Enumerate all fixed-feature devices.
1894          */
1895         if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
1896                 struct acpi_device *device = NULL;
1897
1898                 result = acpi_add_single_object(&device, NULL,
1899                                                 ACPI_BUS_TYPE_POWER_BUTTON,
1900                                                 ACPI_STA_DEFAULT);
1901                 if (result)
1902                         return result;
1903
1904                 device->flags.match_driver = true;
1905                 result = device_attach(&device->dev);
1906                 if (result < 0)
1907                         return result;
1908
1909                 device_init_wakeup(&device->dev, true);
1910         }
1911
1912         if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
1913                 struct acpi_device *device = NULL;
1914
1915                 result = acpi_add_single_object(&device, NULL,
1916                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
1917                                                 ACPI_STA_DEFAULT);
1918                 if (result)
1919                         return result;
1920
1921                 device->flags.match_driver = true;
1922                 result = device_attach(&device->dev);
1923         }
1924
1925         return result < 0 ? result : 0;
1926 }
1927
1928 static bool acpi_scan_initialized;
1929
1930 int __init acpi_scan_init(void)
1931 {
1932         int result;
1933
1934         acpi_pci_root_init();
1935         acpi_pci_link_init();
1936         acpi_processor_init();
1937         acpi_lpss_init();
1938         acpi_apd_init();
1939         acpi_cmos_rtc_init();
1940         acpi_container_init();
1941         acpi_memory_hotplug_init();
1942         acpi_pnp_init();
1943         acpi_int340x_thermal_init();
1944         acpi_amba_init();
1945
1946         acpi_scan_add_handler(&generic_device_handler);
1947
1948         mutex_lock(&acpi_scan_lock);
1949         /*
1950          * Enumerate devices in the ACPI namespace.
1951          */
1952         result = acpi_bus_scan(ACPI_ROOT_OBJECT);
1953         if (result)
1954                 goto out;
1955
1956         result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
1957         if (result)
1958                 goto out;
1959
1960         /* Fixed feature devices do not exist on HW-reduced platform */
1961         if (!acpi_gbl_reduced_hardware) {
1962                 result = acpi_bus_scan_fixed();
1963                 if (result) {
1964                         acpi_detach_data(acpi_root->handle,
1965                                          acpi_scan_drop_device);
1966                         acpi_device_del(acpi_root);
1967                         put_device(&acpi_root->dev);
1968                         goto out;
1969                 }
1970         }
1971
1972         acpi_update_all_gpes();
1973
1974         acpi_scan_initialized = true;
1975
1976  out:
1977         mutex_unlock(&acpi_scan_lock);
1978         return result;
1979 }
1980
1981 static struct acpi_probe_entry *ape;
1982 static int acpi_probe_count;
1983 static DEFINE_SPINLOCK(acpi_probe_lock);
1984
1985 static int __init acpi_match_madt(struct acpi_subtable_header *header,
1986                                   const unsigned long end)
1987 {
1988         if (!ape->subtable_valid || ape->subtable_valid(header, ape))
1989                 if (!ape->probe_subtbl(header, end))
1990                         acpi_probe_count++;
1991
1992         return 0;
1993 }
1994
1995 int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr)
1996 {
1997         int count = 0;
1998
1999         if (acpi_disabled)
2000                 return 0;
2001
2002         spin_lock(&acpi_probe_lock);
2003         for (ape = ap_head; nr; ape++, nr--) {
2004                 if (ACPI_COMPARE_NAME(ACPI_SIG_MADT, ape->id)) {
2005                         acpi_probe_count = 0;
2006                         acpi_table_parse_madt(ape->type, acpi_match_madt, 0);
2007                         count += acpi_probe_count;
2008                 } else {
2009                         int res;
2010                         res = acpi_table_parse(ape->id, ape->probe_table);
2011                         if (!res)
2012                                 count++;
2013                 }
2014         }
2015         spin_unlock(&acpi_probe_lock);
2016
2017         return count;
2018 }
2019
2020 struct acpi_table_events_work {
2021         struct work_struct work;
2022         void *table;
2023         u32 event;
2024 };
2025
2026 static void acpi_table_events_fn(struct work_struct *work)
2027 {
2028         struct acpi_table_events_work *tew;
2029
2030         tew = container_of(work, struct acpi_table_events_work, work);
2031
2032         if (tew->event == ACPI_TABLE_EVENT_LOAD) {
2033                 acpi_scan_lock_acquire();
2034                 acpi_bus_scan(ACPI_ROOT_OBJECT);
2035                 acpi_scan_lock_release();
2036         }
2037
2038         kfree(tew);
2039 }
2040
2041 void acpi_scan_table_handler(u32 event, void *table, void *context)
2042 {
2043         struct acpi_table_events_work *tew;
2044
2045         if (!acpi_scan_initialized)
2046                 return;
2047
2048         if (event != ACPI_TABLE_EVENT_LOAD)
2049                 return;
2050
2051         tew = kmalloc(sizeof(*tew), GFP_KERNEL);
2052         if (!tew)
2053                 return;
2054
2055         INIT_WORK(&tew->work, acpi_table_events_fn);
2056         tew->table = table;
2057         tew->event = event;
2058
2059         schedule_work(&tew->work);
2060 }
2061
2062 int acpi_reconfig_notifier_register(struct notifier_block *nb)
2063 {
2064         return blocking_notifier_chain_register(&acpi_reconfig_chain, nb);
2065 }
2066 EXPORT_SYMBOL(acpi_reconfig_notifier_register);
2067
2068 int acpi_reconfig_notifier_unregister(struct notifier_block *nb)
2069 {
2070         return blocking_notifier_chain_unregister(&acpi_reconfig_chain, nb);
2071 }
2072 EXPORT_SYMBOL(acpi_reconfig_notifier_unregister);