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/acpi_iort.h>
  11 #include <linux/signal.h>
  12 #include <linux/kthread.h>
  13 #include <linux/dmi.h>
  14 #include <linux/nls.h>
  15 #include <linux/dma-mapping.h>
  16 #include <linux/platform_data/x86/apple.h>
  17
  18 #include <asm/pgtable.h>
  19
  20 #include "internal.h"
  21
  22 #define _COMPONENT              ACPI_BUS_COMPONENT
  23 ACPI_MODULE_NAME("scan");
  24 extern struct acpi_device *acpi_root;
  25
  26 #define ACPI_BUS_CLASS                  "system_bus"
  27 #define ACPI_BUS_HID                    "LNXSYBUS"
  28 #define ACPI_BUS_DEVICE_NAME            "System Bus"
  29
  30 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
  31
  32 #define INVALID_ACPI_HANDLE     ((acpi_handle)empty_zero_page)
  33
  34 static const char *dummy_hid = "device";
  35
  36 static LIST_HEAD(acpi_dep_list);
  37 static DEFINE_MUTEX(acpi_dep_list_lock);
  38 LIST_HEAD(acpi_bus_id_list);
  39 static DEFINE_MUTEX(acpi_scan_lock);
  40 static LIST_HEAD(acpi_scan_handlers_list);
  41 DEFINE_MUTEX(acpi_device_lock);
  42 LIST_HEAD(acpi_wakeup_device_list);
  43 static DEFINE_MUTEX(acpi_hp_context_lock);
  44
  45 /*
  46  * The UART device described by the SPCR table is the only object which needs
  47  * special-casing. Everything else is covered by ACPI namespace paths in STAO
  48  * table.
  49  */
  50 static u64 spcr_uart_addr;
  51
  52 struct acpi_dep_data {
  53         struct list_head node;
  54         acpi_handle master;
  55         acpi_handle slave;
  56 };
  57
  58 void acpi_scan_lock_acquire(void)
  59 {
  60         mutex_lock(&acpi_scan_lock);
  61 }
  62 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
  63
  64 void acpi_scan_lock_release(void)
  65 {
  66         mutex_unlock(&acpi_scan_lock);
  67 }
  68 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
  69
  70 void acpi_lock_hp_context(void)
  71 {
  72         mutex_lock(&acpi_hp_context_lock);
  73 }
  74
  75 void acpi_unlock_hp_context(void)
  76 {
  77         mutex_unlock(&acpi_hp_context_lock);
  78 }
  79
  80 void acpi_initialize_hp_context(struct acpi_device *adev,
  81                                 struct acpi_hotplug_context *hp,
  82                                 int (*notify)(struct acpi_device *, u32),
  83                                 void (*uevent)(struct acpi_device *, u32))
  84 {
  85         acpi_lock_hp_context();
  86         hp->notify = notify;
  87         hp->uevent = uevent;
  88         acpi_set_hp_context(adev, hp);
  89         acpi_unlock_hp_context();
  90 }
  91 EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
  92
  93 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
  94 {
  95         if (!handler)
  96                 return -EINVAL;
  97
  98         list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
  99         return 0;
 100 }
 101
 102 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
 103                                        const char *hotplug_profile_name)
 104 {
 105         int error;
 106
 107         error = acpi_scan_add_handler(handler);
 108         if (error)
 109                 return error;
 110
 111         acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
 112         return 0;
 113 }
 114
 115 bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
 116 {
 117         struct acpi_device_physical_node *pn;
 118         bool offline = true;
 119
 120         /*
 121          * acpi_container_offline() calls this for all of the container's
 122          * children under the container's physical_node_lock lock.
 123          */
 124         mutex_lock_nested(&adev->physical_node_lock, SINGLE_DEPTH_NESTING);
 125
 126         list_for_each_entry(pn, &adev->physical_node_list, node)
 127                 if (device_supports_offline(pn->dev) && !pn->dev->offline) {
 128                         if (uevent)
 129                                 kobject_uevent(&pn->dev->kobj, KOBJ_CHANGE);
 130
 131                         offline = false;
 132                         break;
 133                 }
 134
 135         mutex_unlock(&adev->physical_node_lock);
 136         return offline;
 137 }
 138
 139 static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
 140                                     void **ret_p)
 141 {
 142         struct acpi_device *device = NULL;
 143         struct acpi_device_physical_node *pn;
 144         bool second_pass = (bool)data;
 145         acpi_status status = AE_OK;
 146
 147         if (acpi_bus_get_device(handle, &device))
 148                 return AE_OK;
 149
 150         if (device->handler && !device->handler->hotplug.enabled) {
 151                 *ret_p = &device->dev;
 152                 return AE_SUPPORT;
 153         }
 154
 155         mutex_lock(&device->physical_node_lock);
 156
 157         list_for_each_entry(pn, &device->physical_node_list, node) {
 158                 int ret;
 159
 160                 if (second_pass) {
 161                         /* Skip devices offlined by the first pass. */
 162                         if (pn->put_online)
 163                                 continue;
 164                 } else {
 165                         pn->put_online = false;
 166                 }
 167                 ret = device_offline(pn->dev);
 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)
 237                         acpi_bus_offline(handle, 0, (void *)true,
 238                                          (void **)&errdev);
 239
 240                 if (errdev) {
 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                 if (!acpi_scan_is_offline(device, true))
 260                         return -EBUSY;
 261         } else {
 262                 int error = acpi_scan_try_to_offline(device);
 263                 if (error)
 264                         return error;
 265         }
 266
 267         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 268                 "Hot-removing device %s...\n", dev_name(&device->dev)));
 269
 270         acpi_bus_trim(device);
 271
 272         acpi_evaluate_lck(handle, 0);
 273         /*
 274          * TBD: _EJD support.
 275          */
 276         status = acpi_evaluate_ej0(handle);
 277         if (status == AE_NOT_FOUND)
 278                 return -ENODEV;
 279         else if (ACPI_FAILURE(status))
 280                 return -EIO;
 281
 282         /*
 283          * Verify if eject was indeed successful.  If not, log an error
 284          * message.  No need to call _OST since _EJ0 call was made OK.
 285          */
 286         status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
 287         if (ACPI_FAILURE(status)) {
 288                 acpi_handle_warn(handle,
 289                         "Status check after eject failed (0x%x)\n", status);
 290         } else if (sta & ACPI_STA_DEVICE_ENABLED) {
 291                 acpi_handle_warn(handle,
 292                         "Eject incomplete - status 0x%llx\n", sta);
 293         }
 294
 295         return 0;
 296 }
 297
 298 static int acpi_scan_device_not_present(struct acpi_device *adev)
 299 {
 300         if (!acpi_device_enumerated(adev)) {
 301                 dev_warn(&adev->dev, "Still not present\n");
 302                 return -EALREADY;
 303         }
 304         acpi_bus_trim(adev);
 305         return 0;
 306 }
 307
 308 static int acpi_scan_device_check(struct acpi_device *adev)
 309 {
 310         int error;
 311
 312         acpi_bus_get_status(adev);
 313         if (adev->status.present || adev->status.functional) {
 314                 /*
 315                  * This function is only called for device objects for which
 316                  * matching scan handlers exist.  The only situation in which
 317                  * the scan handler is not attached to this device object yet
 318                  * is when the device has just appeared (either it wasn't
 319                  * present at all before or it was removed and then added
 320                  * again).
 321                  */
 322                 if (adev->handler) {
 323                         dev_warn(&adev->dev, "Already enumerated\n");
 324                         return -EALREADY;
 325                 }
 326                 error = acpi_bus_scan(adev->handle);
 327                 if (error) {
 328                         dev_warn(&adev->dev, "Namespace scan failure\n");
 329                         return error;
 330                 }
 331                 if (!adev->handler) {
 332                         dev_warn(&adev->dev, "Enumeration failure\n");
 333                         error = -ENODEV;
 334                 }
 335         } else {
 336                 error = acpi_scan_device_not_present(adev);
 337         }
 338         return error;
 339 }
 340
 341 static int acpi_scan_bus_check(struct acpi_device *adev)
 342 {
 343         struct acpi_scan_handler *handler = adev->handler;
 344         struct acpi_device *child;
 345         int error;
 346
 347         acpi_bus_get_status(adev);
 348         if (!(adev->status.present || adev->status.functional)) {
 349                 acpi_scan_device_not_present(adev);
 350                 return 0;
 351         }
 352         if (handler && handler->hotplug.scan_dependent)
 353                 return handler->hotplug.scan_dependent(adev);
 354
 355         error = acpi_bus_scan(adev->handle);
 356         if (error) {
 357                 dev_warn(&adev->dev, "Namespace scan failure\n");
 358                 return error;
 359         }
 360         list_for_each_entry(child, &adev->children, node) {
 361                 error = acpi_scan_bus_check(child);
 362                 if (error)
 363                         return error;
 364         }
 365         return 0;
 366 }
 367
 368 static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type)
 369 {
 370         switch (type) {
 371         case ACPI_NOTIFY_BUS_CHECK:
 372                 return acpi_scan_bus_check(adev);
 373         case ACPI_NOTIFY_DEVICE_CHECK:
 374                 return acpi_scan_device_check(adev);
 375         case ACPI_NOTIFY_EJECT_REQUEST:
 376         case ACPI_OST_EC_OSPM_EJECT:
 377                 if (adev->handler && !adev->handler->hotplug.enabled) {
 378                         dev_info(&adev->dev, "Eject disabled\n");
 379                         return -EPERM;
 380                 }
 381                 acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST,
 382                                   ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
 383                 return acpi_scan_hot_remove(adev);
 384         }
 385         return -EINVAL;
 386 }
 387
 388 void acpi_device_hotplug(struct acpi_device *adev, u32 src)
 389 {
 390         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
 391         int error = -ENODEV;
 392
 393         lock_device_hotplug();
 394         mutex_lock(&acpi_scan_lock);
 395
 396         /*
 397          * The device object's ACPI handle cannot become invalid as long as we
 398          * are holding acpi_scan_lock, but it might have become invalid before
 399          * that lock was acquired.
 400          */
 401         if (adev->handle == INVALID_ACPI_HANDLE)
 402                 goto err_out;
 403
 404         if (adev->flags.is_dock_station) {
 405                 error = dock_notify(adev, src);
 406         } else if (adev->flags.hotplug_notify) {
 407                 error = acpi_generic_hotplug_event(adev, src);
 408         } else {
 409                 int (*notify)(struct acpi_device *, u32);
 410
 411                 acpi_lock_hp_context();
 412                 notify = adev->hp ? adev->hp->notify : NULL;
 413                 acpi_unlock_hp_context();
 414                 /*
 415                  * There may be additional notify handlers for device objects
 416                  * without the .event() callback, so ignore them here.
 417                  */
 418                 if (notify)
 419                         error = notify(adev, src);
 420                 else
 421                         goto out;
 422         }
 423         switch (error) {
 424         case 0:
 425                 ost_code = ACPI_OST_SC_SUCCESS;
 426                 break;
 427         case -EPERM:
 428                 ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
 429                 break;
 430         case -EBUSY:
 431                 ost_code = ACPI_OST_SC_DEVICE_BUSY;
 432                 break;
 433         default:
 434                 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
 435                 break;
 436         }
 437
 438  err_out:
 439         acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
 440
 441  out:
 442         acpi_bus_put_acpi_device(adev);
 443         mutex_unlock(&acpi_scan_lock);
 444         unlock_device_hotplug();
 445 }
 446
 447 static void acpi_free_power_resources_lists(struct acpi_device *device)
 448 {
 449         int i;
 450
 451         if (device->wakeup.flags.valid)
 452                 acpi_power_resources_list_free(&device->wakeup.resources);
 453
 454         if (!device->power.flags.power_resources)
 455                 return;
 456
 457         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
 458                 struct acpi_device_power_state *ps = &device->power.states[i];
 459                 acpi_power_resources_list_free(&ps->resources);
 460         }
 461 }
 462
 463 static void acpi_device_release(struct device *dev)
 464 {
 465         struct acpi_device *acpi_dev = to_acpi_device(dev);
 466
 467         acpi_free_properties(acpi_dev);
 468         acpi_free_pnp_ids(&acpi_dev->pnp);
 469         acpi_free_power_resources_lists(acpi_dev);
 470         kfree(acpi_dev);
 471 }
 472
 473 static void acpi_device_del(struct acpi_device *device)
 474 {
 475         struct acpi_device_bus_id *acpi_device_bus_id;
 476
 477         mutex_lock(&acpi_device_lock);
 478         if (device->parent)
 479                 list_del(&device->node);
 480
 481         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node)
 482                 if (!strcmp(acpi_device_bus_id->bus_id,
 483                             acpi_device_hid(device))) {
 484                         if (acpi_device_bus_id->instance_no > 0)
 485                                 acpi_device_bus_id->instance_no--;
 486                         else {
 487                                 list_del(&acpi_device_bus_id->node);
 488                                 kfree(acpi_device_bus_id);
 489                         }
 490                         break;
 491                 }
 492
 493         list_del(&device->wakeup_list);
 494         mutex_unlock(&acpi_device_lock);
 495
 496         acpi_power_add_remove_device(device, false);
 497         acpi_device_remove_files(device);
 498         if (device->remove)
 499                 device->remove(device);
 500
 501         device_del(&device->dev);
 502 }
 503
 504 static BLOCKING_NOTIFIER_HEAD(acpi_reconfig_chain);
 505
 506 static LIST_HEAD(acpi_device_del_list);
 507 static DEFINE_MUTEX(acpi_device_del_lock);
 508
 509 static void acpi_device_del_work_fn(struct work_struct *work_not_used)
 510 {
 511         for (;;) {
 512                 struct acpi_device *adev;
 513
 514                 mutex_lock(&acpi_device_del_lock);
 515
 516                 if (list_empty(&acpi_device_del_list)) {
 517                         mutex_unlock(&acpi_device_del_lock);
 518                         break;
 519                 }
 520                 adev = list_first_entry(&acpi_device_del_list,
 521                                         struct acpi_device, del_list);
 522                 list_del(&adev->del_list);
 523
 524                 mutex_unlock(&acpi_device_del_lock);
 525
 526                 blocking_notifier_call_chain(&acpi_reconfig_chain,
 527                                              ACPI_RECONFIG_DEVICE_REMOVE, adev);
 528
 529                 acpi_device_del(adev);
 530                 /*
 531                  * Drop references to all power resources that might have been
 532                  * used by the device.
 533                  */
 534                 acpi_power_transition(adev, ACPI_STATE_D3_COLD);
 535                 put_device(&adev->dev);
 536         }
 537 }
 538
 539 /**
 540  * acpi_scan_drop_device - Drop an ACPI device object.
 541  * @handle: Handle of an ACPI namespace node, not used.
 542  * @context: Address of the ACPI device object to drop.
 543  *
 544  * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
 545  * namespace node the device object pointed to by @context is attached to.
 546  *
 547  * The unregistration is carried out asynchronously to avoid running
 548  * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
 549  * ensure the correct ordering (the device objects must be unregistered in the
 550  * same order in which the corresponding namespace nodes are deleted).
 551  */
 552 static void acpi_scan_drop_device(acpi_handle handle, void *context)
 553 {
 554         static DECLARE_WORK(work, acpi_device_del_work_fn);
 555         struct acpi_device *adev = context;
 556
 557         mutex_lock(&acpi_device_del_lock);
 558
 559         /*
 560          * Use the ACPI hotplug workqueue which is ordered, so this work item
 561          * won't run after any hotplug work items submitted subsequently.  That
 562          * prevents attempts to register device objects identical to those being
 563          * deleted from happening concurrently (such attempts result from
 564          * hotplug events handled via the ACPI hotplug workqueue).  It also will
 565          * run after all of the work items submitted previosuly, which helps
 566          * those work items to ensure that they are not accessing stale device
 567          * objects.
 568          */
 569         if (list_empty(&acpi_device_del_list))
 570                 acpi_queue_hotplug_work(&work);
 571
 572         list_add_tail(&adev->del_list, &acpi_device_del_list);
 573         /* Make acpi_ns_validate_handle() return NULL for this handle. */
 574         adev->handle = INVALID_ACPI_HANDLE;
 575
 576         mutex_unlock(&acpi_device_del_lock);
 577 }
 578
 579 static int acpi_get_device_data(acpi_handle handle, struct acpi_device **device,
 580                                 void (*callback)(void *))
 581 {
 582         acpi_status status;
 583
 584         if (!device)
 585                 return -EINVAL;
 586
 587         status = acpi_get_data_full(handle, acpi_scan_drop_device,
 588                                     (void **)device, callback);
 589         if (ACPI_FAILURE(status) || !*device) {
 590                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
 591                                   handle));
 592                 return -ENODEV;
 593         }
 594         return 0;
 595 }
 596
 597 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
 598 {
 599         return acpi_get_device_data(handle, device, NULL);
 600 }
 601 EXPORT_SYMBOL(acpi_bus_get_device);
 602
 603 static void get_acpi_device(void *dev)
 604 {
 605         if (dev)
 606                 get_device(&((struct acpi_device *)dev)->dev);
 607 }
 608
 609 struct acpi_device *acpi_bus_get_acpi_device(acpi_handle handle)
 610 {
 611         struct acpi_device *adev = NULL;
 612
 613         acpi_get_device_data(handle, &adev, get_acpi_device);
 614         return adev;
 615 }
 616
 617 void acpi_bus_put_acpi_device(struct acpi_device *adev)
 618 {
 619         put_device(&adev->dev);
 620 }
 621
 622 int acpi_device_add(struct acpi_device *device,
 623                     void (*release)(struct device *))
 624 {
 625         int result;
 626         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
 627         int found = 0;
 628
 629         if (device->handle) {
 630                 acpi_status status;
 631
 632                 status = acpi_attach_data(device->handle, acpi_scan_drop_device,
 633                                           device);
 634                 if (ACPI_FAILURE(status)) {
 635                         acpi_handle_err(device->handle,
 636                                         "Unable to attach device data\n");
 637                         return -ENODEV;
 638                 }
 639         }
 640
 641         /*
 642          * Linkage
 643          * -------
 644          * Link this device to its parent and siblings.
 645          */
 646         INIT_LIST_HEAD(&device->children);
 647         INIT_LIST_HEAD(&device->node);
 648         INIT_LIST_HEAD(&device->wakeup_list);
 649         INIT_LIST_HEAD(&device->physical_node_list);
 650         INIT_LIST_HEAD(&device->del_list);
 651         mutex_init(&device->physical_node_lock);
 652
 653         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
 654         if (!new_bus_id) {
 655                 pr_err(PREFIX "Memory allocation error\n");
 656                 result = -ENOMEM;
 657                 goto err_detach;
 658         }
 659
 660         mutex_lock(&acpi_device_lock);
 661         /*
 662          * Find suitable bus_id and instance number in acpi_bus_id_list
 663          * If failed, create one and link it into acpi_bus_id_list
 664          */
 665         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
 666                 if (!strcmp(acpi_device_bus_id->bus_id,
 667                             acpi_device_hid(device))) {
 668                         acpi_device_bus_id->instance_no++;
 669                         found = 1;
 670                         kfree(new_bus_id);
 671                         break;
 672                 }
 673         }
 674         if (!found) {
 675                 acpi_device_bus_id = new_bus_id;
 676                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
 677                 acpi_device_bus_id->instance_no = 0;
 678                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
 679         }
 680         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
 681
 682         if (device->parent)
 683                 list_add_tail(&device->node, &device->parent->children);
 684
 685         if (device->wakeup.flags.valid)
 686                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
 687         mutex_unlock(&acpi_device_lock);
 688
 689         if (device->parent)
 690                 device->dev.parent = &device->parent->dev;
 691         device->dev.bus = &acpi_bus_type;
 692         device->dev.release = release;
 693         result = device_add(&device->dev);
 694         if (result) {
 695                 dev_err(&device->dev, "Error registering device\n");
 696                 goto err;
 697         }
 698
 699         result = acpi_device_setup_files(device);
 700         if (result)
 701                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
 702                        dev_name(&device->dev));
 703
 704         return 0;
 705
 706  err:
 707         mutex_lock(&acpi_device_lock);
 708         if (device->parent)
 709                 list_del(&device->node);
 710         list_del(&device->wakeup_list);
 711         mutex_unlock(&acpi_device_lock);
 712
 713  err_detach:
 714         acpi_detach_data(device->handle, acpi_scan_drop_device);
 715         return result;
 716 }
 717
 718 /* --------------------------------------------------------------------------
 719                                  Device Enumeration
 720    -------------------------------------------------------------------------- */
 721 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
 722 {
 723         struct acpi_device *device = NULL;
 724         acpi_status status;
 725
 726         /*
 727          * Fixed hardware devices do not appear in the namespace and do not
 728          * have handles, but we fabricate acpi_devices for them, so we have
 729          * to deal with them specially.
 730          */
 731         if (!handle)
 732                 return acpi_root;
 733
 734         do {
 735                 status = acpi_get_parent(handle, &handle);
 736                 if (ACPI_FAILURE(status))
 737                         return status == AE_NULL_ENTRY ? NULL : acpi_root;
 738         } while (acpi_bus_get_device(handle, &device));
 739         return device;
 740 }
 741
 742 acpi_status
 743 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
 744 {
 745         acpi_status status;
 746         acpi_handle tmp;
 747         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 748         union acpi_object *obj;
 749
 750         status = acpi_get_handle(handle, "_EJD", &tmp);
 751         if (ACPI_FAILURE(status))
 752                 return status;
 753
 754         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
 755         if (ACPI_SUCCESS(status)) {
 756                 obj = buffer.pointer;
 757                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
 758                                          ejd);
 759                 kfree(buffer.pointer);
 760         }
 761         return status;
 762 }
 763 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
 764
 765 static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
 766                                         struct acpi_device_wakeup *wakeup)
 767 {
 768         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 769         union acpi_object *package = NULL;
 770         union acpi_object *element = NULL;
 771         acpi_status status;
 772         int err = -ENODATA;
 773
 774         if (!wakeup)
 775                 return -EINVAL;
 776
 777         INIT_LIST_HEAD(&wakeup->resources);
 778
 779         /* _PRW */
 780         status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
 781         if (ACPI_FAILURE(status)) {
 782                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
 783                 return err;
 784         }
 785
 786         package = (union acpi_object *)buffer.pointer;
 787
 788         if (!package || package->package.count < 2)
 789                 goto out;
 790
 791         element = &(package->package.elements[0]);
 792         if (!element)
 793                 goto out;
 794
 795         if (element->type == ACPI_TYPE_PACKAGE) {
 796                 if ((element->package.count < 2) ||
 797                     (element->package.elements[0].type !=
 798                      ACPI_TYPE_LOCAL_REFERENCE)
 799                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
 800                         goto out;
 801
 802                 wakeup->gpe_device =
 803                     element->package.elements[0].reference.handle;
 804                 wakeup->gpe_number =
 805                     (u32) element->package.elements[1].integer.value;
 806         } else if (element->type == ACPI_TYPE_INTEGER) {
 807                 wakeup->gpe_device = NULL;
 808                 wakeup->gpe_number = element->integer.value;
 809         } else {
 810                 goto out;
 811         }
 812
 813         element = &(package->package.elements[1]);
 814         if (element->type != ACPI_TYPE_INTEGER)
 815                 goto out;
 816
 817         wakeup->sleep_state = element->integer.value;
 818
 819         err = acpi_extract_power_resources(package, 2, &wakeup->resources);
 820         if (err)
 821                 goto out;
 822
 823         if (!list_empty(&wakeup->resources)) {
 824                 int sleep_state;
 825
 826                 err = acpi_power_wakeup_list_init(&wakeup->resources,
 827                                                   &sleep_state);
 828                 if (err) {
 829                         acpi_handle_warn(handle, "Retrieving current states "
 830                                          "of wakeup power resources failed\n");
 831                         acpi_power_resources_list_free(&wakeup->resources);
 832                         goto out;
 833                 }
 834                 if (sleep_state < wakeup->sleep_state) {
 835                         acpi_handle_warn(handle, "Overriding _PRW sleep state "
 836                                          "(S%d) by S%d from power resources\n",
 837                                          (int)wakeup->sleep_state, sleep_state);
 838                         wakeup->sleep_state = sleep_state;
 839                 }
 840         }
 841
 842  out:
 843         kfree(buffer.pointer);
 844         return err;
 845 }
 846
 847 static bool acpi_wakeup_gpe_init(struct acpi_device *device)
 848 {
 849         static const struct acpi_device_id button_device_ids[] = {
 850                 {"PNP0C0C", 0},
 851                 {"PNP0C0D", 0},
 852                 {"PNP0C0E", 0},
 853                 {"", 0},
 854         };
 855         struct acpi_device_wakeup *wakeup = &device->wakeup;
 856         acpi_status status;
 857
 858         wakeup->flags.notifier_present = 0;
 859
 860         /* Power button, Lid switch always enable wakeup */
 861         if (!acpi_match_device_ids(device, button_device_ids)) {
 862                 if (!acpi_match_device_ids(device, &button_device_ids[1])) {
 863                         /* Do not use Lid/sleep button for S5 wakeup */
 864                         if (wakeup->sleep_state == ACPI_STATE_S5)
 865                                 wakeup->sleep_state = ACPI_STATE_S4;
 866                 }
 867                 acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
 868                 device_set_wakeup_capable(&device->dev, true);
 869                 return true;
 870         }
 871
 872         status = acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
 873                                          wakeup->gpe_number);
 874         return ACPI_SUCCESS(status);
 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 = acpi_wakeup_gpe_init(device);
 893         device->wakeup.prepare_count = 0;
 894         /*
 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         case ACPI_BUS_TYPE_ECDT_EC:
1028                 strcpy(device->pnp.bus_id, "ECDT");
1029                 break;
1030         default:
1031                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1032                 /* Clean up trailing underscores (if any) */
1033                 for (i = 3; i > 1; i--) {
1034                         if (bus_id[i] == '_')
1035                                 bus_id[i] = '\0';
1036                         else
1037                                 break;
1038                 }
1039                 strcpy(device->pnp.bus_id, bus_id);
1040                 break;
1041         }
1042 }
1043
1044 /*
1045  * acpi_ata_match - see if an acpi object is an ATA device
1046  *
1047  * If an acpi object has one of the ACPI ATA methods defined,
1048  * then we can safely call it an ATA device.
1049  */
1050 bool acpi_ata_match(acpi_handle handle)
1051 {
1052         return acpi_has_method(handle, "_GTF") ||
1053                acpi_has_method(handle, "_GTM") ||
1054                acpi_has_method(handle, "_STM") ||
1055                acpi_has_method(handle, "_SDD");
1056 }
1057
1058 /*
1059  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1060  *
1061  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1062  * then we can safely call it an ejectable drive bay
1063  */
1064 bool acpi_bay_match(acpi_handle handle)
1065 {
1066         acpi_handle phandle;
1067
1068         if (!acpi_has_method(handle, "_EJ0"))
1069                 return false;
1070         if (acpi_ata_match(handle))
1071                 return true;
1072         if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1073                 return false;
1074
1075         return acpi_ata_match(phandle);
1076 }
1077
1078 bool acpi_device_is_battery(struct acpi_device *adev)
1079 {
1080         struct acpi_hardware_id *hwid;
1081
1082         list_for_each_entry(hwid, &adev->pnp.ids, list)
1083                 if (!strcmp("PNP0C0A", hwid->id))
1084                         return true;
1085
1086         return false;
1087 }
1088
1089 static bool is_ejectable_bay(struct acpi_device *adev)
1090 {
1091         acpi_handle handle = adev->handle;
1092
1093         if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
1094                 return true;
1095
1096         return acpi_bay_match(handle);
1097 }
1098
1099 /*
1100  * acpi_dock_match - see if an acpi object has a _DCK method
1101  */
1102 bool acpi_dock_match(acpi_handle handle)
1103 {
1104         return acpi_has_method(handle, "_DCK");
1105 }
1106
1107 static acpi_status
1108 acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
1109                           void **return_value)
1110 {
1111         long *cap = context;
1112
1113         if (acpi_has_method(handle, "_BCM") &&
1114             acpi_has_method(handle, "_BCL")) {
1115                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight "
1116                                   "support\n"));
1117                 *cap |= ACPI_VIDEO_BACKLIGHT;
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         case ACPI_BUS_TYPE_ECDT_EC:
1311                 acpi_add_id(pnp, ACPI_ECDT_HID);
1312                 break;
1313         }
1314 }
1315
1316 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1317 {
1318         struct acpi_hardware_id *id, *tmp;
1319
1320         list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1321                 kfree_const(id->id);
1322                 kfree(id);
1323         }
1324         kfree(pnp->unique_id);
1325 }
1326
1327 /**
1328  * acpi_dma_supported - Check DMA support for the specified device.
1329  * @adev: The pointer to acpi device
1330  *
1331  * Return false if DMA is not supported. Otherwise, return true
1332  */
1333 bool acpi_dma_supported(struct acpi_device *adev)
1334 {
1335         if (!adev)
1336                 return false;
1337
1338         if (adev->flags.cca_seen)
1339                 return true;
1340
1341         /*
1342         * Per ACPI 6.0 sec 6.2.17, assume devices can do cache-coherent
1343         * DMA on "Intel platforms".  Presumably that includes all x86 and
1344         * ia64, and other arches will set CONFIG_ACPI_CCA_REQUIRED=y.
1345         */
1346         if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1347                 return true;
1348
1349         return false;
1350 }
1351
1352 /**
1353  * acpi_get_dma_attr - Check the supported DMA attr for the specified device.
1354  * @adev: The pointer to acpi device
1355  *
1356  * Return enum dev_dma_attr.
1357  */
1358 enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
1359 {
1360         if (!acpi_dma_supported(adev))
1361                 return DEV_DMA_NOT_SUPPORTED;
1362
1363         if (adev->flags.coherent_dma)
1364                 return DEV_DMA_COHERENT;
1365         else
1366                 return DEV_DMA_NON_COHERENT;
1367 }
1368
1369 /**
1370  * acpi_dma_get_range() - Get device DMA parameters.
1371  *
1372  * @dev: device to configure
1373  * @dma_addr: pointer device DMA address result
1374  * @offset: pointer to the DMA offset result
1375  * @size: pointer to DMA range size result
1376  *
1377  * Evaluate DMA regions and return respectively DMA region start, offset
1378  * and size in dma_addr, offset and size on parsing success; it does not
1379  * update the passed in values on failure.
1380  *
1381  * Return 0 on success, < 0 on failure.
1382  */
1383 int acpi_dma_get_range(struct device *dev, u64 *dma_addr, u64 *offset,
1384                        u64 *size)
1385 {
1386         struct acpi_device *adev;
1387         LIST_HEAD(list);
1388         struct resource_entry *rentry;
1389         int ret;
1390         struct device *dma_dev = dev;
1391         u64 len, dma_start = U64_MAX, dma_end = 0, dma_offset = 0;
1392
1393         /*
1394          * Walk the device tree chasing an ACPI companion with a _DMA
1395          * object while we go. Stop if we find a device with an ACPI
1396          * companion containing a _DMA method.
1397          */
1398         do {
1399                 adev = ACPI_COMPANION(dma_dev);
1400                 if (adev && acpi_has_method(adev->handle, METHOD_NAME__DMA))
1401                         break;
1402
1403                 dma_dev = dma_dev->parent;
1404         } while (dma_dev);
1405
1406         if (!dma_dev)
1407                 return -ENODEV;
1408
1409         if (!acpi_has_method(adev->handle, METHOD_NAME__CRS)) {
1410                 acpi_handle_warn(adev->handle, "_DMA is valid only if _CRS is present\n");
1411                 return -EINVAL;
1412         }
1413
1414         ret = acpi_dev_get_dma_resources(adev, &list);
1415         if (ret > 0) {
1416                 list_for_each_entry(rentry, &list, node) {
1417                         if (dma_offset && rentry->offset != dma_offset) {
1418                                 ret = -EINVAL;
1419                                 dev_warn(dma_dev, "Can't handle multiple windows with different offsets\n");
1420                                 goto out;
1421                         }
1422                         dma_offset = rentry->offset;
1423
1424                         /* Take lower and upper limits */
1425                         if (rentry->res->start < dma_start)
1426                                 dma_start = rentry->res->start;
1427                         if (rentry->res->end > dma_end)
1428                                 dma_end = rentry->res->end;
1429                 }
1430
1431                 if (dma_start >= dma_end) {
1432                         ret = -EINVAL;
1433                         dev_dbg(dma_dev, "Invalid DMA regions configuration\n");
1434                         goto out;
1435                 }
1436
1437                 *dma_addr = dma_start - dma_offset;
1438                 len = dma_end - dma_start;
1439                 *size = max(len, len + 1);
1440                 *offset = dma_offset;
1441         }
1442  out:
1443         acpi_dev_free_resource_list(&list);
1444
1445         return ret >= 0 ? 0 : ret;
1446 }
1447
1448 /**
1449  * acpi_dma_configure - Set-up DMA configuration for the device.
1450  * @dev: The pointer to the device
1451  * @attr: device dma attributes
1452  */
1453 int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr)
1454 {
1455         const struct iommu_ops *iommu;
1456         u64 dma_addr = 0, size = 0;
1457
1458         iort_dma_setup(dev, &dma_addr, &size);
1459
1460         iommu = iort_iommu_configure(dev);
1461         if (IS_ERR(iommu) && PTR_ERR(iommu) == -EPROBE_DEFER)
1462                 return -EPROBE_DEFER;
1463
1464         arch_setup_dma_ops(dev, dma_addr, size,
1465                                 iommu, attr == DEV_DMA_COHERENT);
1466
1467         return 0;
1468 }
1469 EXPORT_SYMBOL_GPL(acpi_dma_configure);
1470
1471 /**
1472  * acpi_dma_deconfigure - Tear-down DMA configuration for the device.
1473  * @dev: The pointer to the device
1474  */
1475 void acpi_dma_deconfigure(struct device *dev)
1476 {
1477         arch_teardown_dma_ops(dev);
1478 }
1479 EXPORT_SYMBOL_GPL(acpi_dma_deconfigure);
1480
1481 static void acpi_init_coherency(struct acpi_device *adev)
1482 {
1483         unsigned long long cca = 0;
1484         acpi_status status;
1485         struct acpi_device *parent = adev->parent;
1486
1487         if (parent && parent->flags.cca_seen) {
1488                 /*
1489                  * From ACPI spec, OSPM will ignore _CCA if an ancestor
1490                  * already saw one.
1491                  */
1492                 adev->flags.cca_seen = 1;
1493                 cca = parent->flags.coherent_dma;
1494         } else {
1495                 status = acpi_evaluate_integer(adev->handle, "_CCA",
1496                                                NULL, &cca);
1497                 if (ACPI_SUCCESS(status))
1498                         adev->flags.cca_seen = 1;
1499                 else if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1500                         /*
1501                          * If architecture does not specify that _CCA is
1502                          * required for DMA-able devices (e.g. x86),
1503                          * we default to _CCA=1.
1504                          */
1505                         cca = 1;
1506                 else
1507                         acpi_handle_debug(adev->handle,
1508                                           "ACPI device is missing _CCA.\n");
1509         }
1510
1511         adev->flags.coherent_dma = cca;
1512 }
1513
1514 static int acpi_check_serial_bus_slave(struct acpi_resource *ares, void *data)
1515 {
1516         bool *is_serial_bus_slave_p = data;
1517
1518         if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
1519                 return 1;
1520
1521         *is_serial_bus_slave_p = true;
1522
1523          /* no need to do more checking */
1524         return -1;
1525 }
1526
1527 static bool acpi_is_serial_bus_slave(struct acpi_device *device)
1528 {
1529         struct list_head resource_list;
1530         bool is_serial_bus_slave = false;
1531
1532         /* Macs use device properties in lieu of _CRS resources */
1533         if (x86_apple_machine &&
1534             (fwnode_property_present(&device->fwnode, "spiSclkPeriod") ||
1535              fwnode_property_present(&device->fwnode, "i2cAddress") ||
1536              fwnode_property_present(&device->fwnode, "baud")))
1537                 return true;
1538
1539         INIT_LIST_HEAD(&resource_list);
1540         acpi_dev_get_resources(device, &resource_list,
1541                                acpi_check_serial_bus_slave,
1542                                &is_serial_bus_slave);
1543         acpi_dev_free_resource_list(&resource_list);
1544
1545         return is_serial_bus_slave;
1546 }
1547
1548 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1549                              int type, unsigned long long sta)
1550 {
1551         INIT_LIST_HEAD(&device->pnp.ids);
1552         device->device_type = type;
1553         device->handle = handle;
1554         device->parent = acpi_bus_get_parent(handle);
1555         device->fwnode.ops = &acpi_device_fwnode_ops;
1556         acpi_set_device_status(device, sta);
1557         acpi_device_get_busid(device);
1558         acpi_set_pnp_ids(handle, &device->pnp, type);
1559         acpi_init_properties(device);
1560         acpi_bus_get_flags(device);
1561         device->flags.match_driver = false;
1562         device->flags.initialized = true;
1563         device->flags.serial_bus_slave = acpi_is_serial_bus_slave(device);
1564         acpi_device_clear_enumerated(device);
1565         device_initialize(&device->dev);
1566         dev_set_uevent_suppress(&device->dev, true);
1567         acpi_init_coherency(device);
1568 }
1569
1570 void acpi_device_add_finalize(struct acpi_device *device)
1571 {
1572         dev_set_uevent_suppress(&device->dev, false);
1573         kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1574 }
1575
1576 static int acpi_add_single_object(struct acpi_device **child,
1577                                   acpi_handle handle, int type,
1578                                   unsigned long long sta)
1579 {
1580         int result;
1581         struct acpi_device *device;
1582         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1583
1584         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1585         if (!device) {
1586                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1587                 return -ENOMEM;
1588         }
1589
1590         acpi_init_device_object(device, handle, type, sta);
1591         acpi_bus_get_power_flags(device);
1592         acpi_bus_get_wakeup_device_flags(device);
1593
1594         result = acpi_device_add(device, acpi_device_release);
1595         if (result) {
1596                 acpi_device_release(&device->dev);
1597                 return result;
1598         }
1599
1600         acpi_power_add_remove_device(device, true);
1601         acpi_device_add_finalize(device);
1602         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1603         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1604                 dev_name(&device->dev), (char *) buffer.pointer,
1605                 device->parent ? dev_name(&device->parent->dev) : "(null)"));
1606         kfree(buffer.pointer);
1607         *child = device;
1608         return 0;
1609 }
1610
1611 static acpi_status acpi_get_resource_memory(struct acpi_resource *ares,
1612                                             void *context)
1613 {
1614         struct resource *res = context;
1615
1616         if (acpi_dev_resource_memory(ares, res))
1617                 return AE_CTRL_TERMINATE;
1618
1619         return AE_OK;
1620 }
1621
1622 static bool acpi_device_should_be_hidden(acpi_handle handle)
1623 {
1624         acpi_status status;
1625         struct resource res;
1626
1627         /* Check if it should ignore the UART device */
1628         if (!(spcr_uart_addr && acpi_has_method(handle, METHOD_NAME__CRS)))
1629                 return false;
1630
1631         /*
1632          * The UART device described in SPCR table is assumed to have only one
1633          * memory resource present. So we only look for the first one here.
1634          */
1635         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1636                                      acpi_get_resource_memory, &res);
1637         if (ACPI_FAILURE(status) || res.start != spcr_uart_addr)
1638                 return false;
1639
1640         acpi_handle_info(handle, "The UART device @%pa in SPCR table will be hidden\n",
1641                          &res.start);
1642
1643         return true;
1644 }
1645
1646 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1647                                     unsigned long long *sta)
1648 {
1649         acpi_status status;
1650         acpi_object_type acpi_type;
1651
1652         status = acpi_get_type(handle, &acpi_type);
1653         if (ACPI_FAILURE(status))
1654                 return -ENODEV;
1655
1656         switch (acpi_type) {
1657         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1658         case ACPI_TYPE_DEVICE:
1659                 if (acpi_device_should_be_hidden(handle))
1660                         return -ENODEV;
1661
1662                 *type = ACPI_BUS_TYPE_DEVICE;
1663                 status = acpi_bus_get_status_handle(handle, sta);
1664                 if (ACPI_FAILURE(status))
1665                         *sta = 0;
1666                 break;
1667         case ACPI_TYPE_PROCESSOR:
1668                 *type = ACPI_BUS_TYPE_PROCESSOR;
1669                 status = acpi_bus_get_status_handle(handle, sta);
1670                 if (ACPI_FAILURE(status))
1671                         return -ENODEV;
1672                 break;
1673         case ACPI_TYPE_THERMAL:
1674                 *type = ACPI_BUS_TYPE_THERMAL;
1675                 *sta = ACPI_STA_DEFAULT;
1676                 break;
1677         case ACPI_TYPE_POWER:
1678                 *type = ACPI_BUS_TYPE_POWER;
1679                 *sta = ACPI_STA_DEFAULT;
1680                 break;
1681         default:
1682                 return -ENODEV;
1683         }
1684
1685         return 0;
1686 }
1687
1688 bool acpi_device_is_present(const struct acpi_device *adev)
1689 {
1690         return adev->status.present || adev->status.functional;
1691 }
1692
1693 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1694                                        const char *idstr,
1695                                        const struct acpi_device_id **matchid)
1696 {
1697         const struct acpi_device_id *devid;
1698
1699         if (handler->match)
1700                 return handler->match(idstr, matchid);
1701
1702         for (devid = handler->ids; devid->id[0]; devid++)
1703                 if (!strcmp((char *)devid->id, idstr)) {
1704                         if (matchid)
1705                                 *matchid = devid;
1706
1707                         return true;
1708                 }
1709
1710         return false;
1711 }
1712
1713 static struct acpi_scan_handler *acpi_scan_match_handler(const char *idstr,
1714                                         const struct acpi_device_id **matchid)
1715 {
1716         struct acpi_scan_handler *handler;
1717
1718         list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1719                 if (acpi_scan_handler_matching(handler, idstr, matchid))
1720                         return handler;
1721
1722         return NULL;
1723 }
1724
1725 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1726 {
1727         if (!!hotplug->enabled == !!val)
1728                 return;
1729
1730         mutex_lock(&acpi_scan_lock);
1731
1732         hotplug->enabled = val;
1733
1734         mutex_unlock(&acpi_scan_lock);
1735 }
1736
1737 static void acpi_scan_init_hotplug(struct acpi_device *adev)
1738 {
1739         struct acpi_hardware_id *hwid;
1740
1741         if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
1742                 acpi_dock_add(adev);
1743                 return;
1744         }
1745         list_for_each_entry(hwid, &adev->pnp.ids, list) {
1746                 struct acpi_scan_handler *handler;
1747
1748                 handler = acpi_scan_match_handler(hwid->id, NULL);
1749                 if (handler) {
1750                         adev->flags.hotplug_notify = true;
1751                         break;
1752                 }
1753         }
1754 }
1755
1756 static void acpi_device_dep_initialize(struct acpi_device *adev)
1757 {
1758         struct acpi_dep_data *dep;
1759         struct acpi_handle_list dep_devices;
1760         acpi_status status;
1761         int i;
1762
1763         if (!acpi_has_method(adev->handle, "_DEP"))
1764                 return;
1765
1766         status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
1767                                         &dep_devices);
1768         if (ACPI_FAILURE(status)) {
1769                 dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
1770                 return;
1771         }
1772
1773         for (i = 0; i < dep_devices.count; i++) {
1774                 struct acpi_device_info *info;
1775                 int skip;
1776
1777                 status = acpi_get_object_info(dep_devices.handles[i], &info);
1778                 if (ACPI_FAILURE(status)) {
1779                         dev_dbg(&adev->dev, "Error reading _DEP device info\n");
1780                         continue;
1781                 }
1782
1783                 /*
1784                  * Skip the dependency of Windows System Power
1785                  * Management Controller
1786                  */
1787                 skip = info->valid & ACPI_VALID_HID &&
1788                         !strcmp(info->hardware_id.string, "INT3396");
1789
1790                 kfree(info);
1791
1792                 if (skip)
1793                         continue;
1794
1795                 dep = kzalloc(sizeof(struct acpi_dep_data), GFP_KERNEL);
1796                 if (!dep)
1797                         return;
1798
1799                 dep->master = dep_devices.handles[i];
1800                 dep->slave  = adev->handle;
1801                 adev->dep_unmet++;
1802
1803                 mutex_lock(&acpi_dep_list_lock);
1804                 list_add_tail(&dep->node , &acpi_dep_list);
1805                 mutex_unlock(&acpi_dep_list_lock);
1806         }
1807 }
1808
1809 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
1810                                       void *not_used, void **return_value)
1811 {
1812         struct acpi_device *device = NULL;
1813         int type;
1814         unsigned long long sta;
1815         int result;
1816
1817         acpi_bus_get_device(handle, &device);
1818         if (device)
1819                 goto out;
1820
1821         result = acpi_bus_type_and_status(handle, &type, &sta);
1822         if (result)
1823                 return AE_OK;
1824
1825         if (type == ACPI_BUS_TYPE_POWER) {
1826                 acpi_add_power_resource(handle);
1827                 return AE_OK;
1828         }
1829
1830         acpi_add_single_object(&device, handle, type, sta);
1831         if (!device)
1832                 return AE_CTRL_DEPTH;
1833
1834         acpi_scan_init_hotplug(device);
1835         acpi_device_dep_initialize(device);
1836
1837  out:
1838         if (!*return_value)
1839                 *return_value = device;
1840
1841         return AE_OK;
1842 }
1843
1844 static void acpi_default_enumeration(struct acpi_device *device)
1845 {
1846         /*
1847          * Do not enumerate SPI/I2C/UART slaves as they will be enumerated by
1848          * their respective parents.
1849          */
1850         if (!device->flags.serial_bus_slave) {
1851                 acpi_create_platform_device(device, NULL);
1852                 acpi_device_set_enumerated(device);
1853         } else {
1854                 blocking_notifier_call_chain(&acpi_reconfig_chain,
1855                                              ACPI_RECONFIG_DEVICE_ADD, device);
1856         }
1857 }
1858
1859 static const struct acpi_device_id generic_device_ids[] = {
1860         {ACPI_DT_NAMESPACE_HID, },
1861         {"", },
1862 };
1863
1864 static int acpi_generic_device_attach(struct acpi_device *adev,
1865                                       const struct acpi_device_id *not_used)
1866 {
1867         /*
1868          * Since ACPI_DT_NAMESPACE_HID is the only ID handled here, the test
1869          * below can be unconditional.
1870          */
1871         if (adev->data.of_compatible)
1872                 acpi_default_enumeration(adev);
1873
1874         return 1;
1875 }
1876
1877 static struct acpi_scan_handler generic_device_handler = {
1878         .ids = generic_device_ids,
1879         .attach = acpi_generic_device_attach,
1880 };
1881
1882 static int acpi_scan_attach_handler(struct acpi_device *device)
1883 {
1884         struct acpi_hardware_id *hwid;
1885         int ret = 0;
1886
1887         list_for_each_entry(hwid, &device->pnp.ids, list) {
1888                 const struct acpi_device_id *devid;
1889                 struct acpi_scan_handler *handler;
1890
1891                 handler = acpi_scan_match_handler(hwid->id, &devid);
1892                 if (handler) {
1893                         if (!handler->attach) {
1894                                 device->pnp.type.platform_id = 0;
1895                                 continue;
1896                         }
1897                         device->handler = handler;
1898                         ret = handler->attach(device, devid);
1899                         if (ret > 0)
1900                                 break;
1901
1902                         device->handler = NULL;
1903                         if (ret < 0)
1904                                 break;
1905                 }
1906         }
1907
1908         return ret;
1909 }
1910
1911 static void acpi_bus_attach(struct acpi_device *device)
1912 {
1913         struct acpi_device *child;
1914         acpi_handle ejd;
1915         int ret;
1916
1917         if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
1918                 register_dock_dependent_device(device, ejd);
1919
1920         acpi_bus_get_status(device);
1921         /* Skip devices that are not present. */
1922         if (!acpi_device_is_present(device)) {
1923                 device->flags.initialized = false;
1924                 acpi_device_clear_enumerated(device);
1925                 device->flags.power_manageable = 0;
1926                 return;
1927         }
1928         if (device->handler)
1929                 goto ok;
1930
1931         if (!device->flags.initialized) {
1932                 device->flags.power_manageable =
1933                         device->power.states[ACPI_STATE_D0].flags.valid;
1934                 if (acpi_bus_init_power(device))
1935                         device->flags.power_manageable = 0;
1936
1937                 device->flags.initialized = true;
1938         } else if (device->flags.visited) {
1939                 goto ok;
1940         }
1941
1942         ret = acpi_scan_attach_handler(device);
1943         if (ret < 0)
1944                 return;
1945
1946         device->flags.match_driver = true;
1947         if (ret > 0 && !device->flags.serial_bus_slave) {
1948                 acpi_device_set_enumerated(device);
1949                 goto ok;
1950         }
1951
1952         ret = device_attach(&device->dev);
1953         if (ret < 0)
1954                 return;
1955
1956         if (!device->pnp.type.platform_id && !device->flags.serial_bus_slave)
1957                 acpi_device_set_enumerated(device);
1958         else
1959                 acpi_default_enumeration(device);
1960
1961  ok:
1962         list_for_each_entry(child, &device->children, node)
1963                 acpi_bus_attach(child);
1964
1965         if (device->handler && device->handler->hotplug.notify_online)
1966                 device->handler->hotplug.notify_online(device);
1967 }
1968
1969 void acpi_walk_dep_device_list(acpi_handle handle)
1970 {
1971         struct acpi_dep_data *dep, *tmp;
1972         struct acpi_device *adev;
1973
1974         mutex_lock(&acpi_dep_list_lock);
1975         list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
1976                 if (dep->master == handle) {
1977                         acpi_bus_get_device(dep->slave, &adev);
1978                         if (!adev)
1979                                 continue;
1980
1981                         adev->dep_unmet--;
1982                         if (!adev->dep_unmet)
1983                                 acpi_bus_attach(adev);
1984                         list_del(&dep->node);
1985                         kfree(dep);
1986                 }
1987         }
1988         mutex_unlock(&acpi_dep_list_lock);
1989 }
1990 EXPORT_SYMBOL_GPL(acpi_walk_dep_device_list);
1991
1992 /**
1993  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
1994  * @handle: Root of the namespace scope to scan.
1995  *
1996  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
1997  * found devices.
1998  *
1999  * If no devices were found, -ENODEV is returned, but it does not mean that
2000  * there has been a real error.  There just have been no suitable ACPI objects
2001  * in the table trunk from which the kernel could create a device and add an
2002  * appropriate driver.
2003  *
2004  * Must be called under acpi_scan_lock.
2005  */
2006 int acpi_bus_scan(acpi_handle handle)
2007 {
2008         void *device = NULL;
2009
2010         if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
2011                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2012                                     acpi_bus_check_add, NULL, NULL, &device);
2013
2014         if (device) {
2015                 acpi_bus_attach(device);
2016                 return 0;
2017         }
2018         return -ENODEV;
2019 }
2020 EXPORT_SYMBOL(acpi_bus_scan);
2021
2022 /**
2023  * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
2024  * @adev: Root of the ACPI namespace scope to walk.
2025  *
2026  * Must be called under acpi_scan_lock.
2027  */
2028 void acpi_bus_trim(struct acpi_device *adev)
2029 {
2030         struct acpi_scan_handler *handler = adev->handler;
2031         struct acpi_device *child;
2032
2033         list_for_each_entry_reverse(child, &adev->children, node)
2034                 acpi_bus_trim(child);
2035
2036         adev->flags.match_driver = false;
2037         if (handler) {
2038                 if (handler->detach)
2039                         handler->detach(adev);
2040
2041                 adev->handler = NULL;
2042         } else {
2043                 device_release_driver(&adev->dev);
2044         }
2045         /*
2046          * Most likely, the device is going away, so put it into D3cold before
2047          * that.
2048          */
2049         acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
2050         adev->flags.initialized = false;
2051         acpi_device_clear_enumerated(adev);
2052 }
2053 EXPORT_SYMBOL_GPL(acpi_bus_trim);
2054
2055 int acpi_bus_register_early_device(int type)
2056 {
2057         struct acpi_device *device = NULL;
2058         int result;
2059
2060         result = acpi_add_single_object(&device, NULL,
2061                                         type, ACPI_STA_DEFAULT);
2062         if (result)
2063                 return result;
2064
2065         device->flags.match_driver = true;
2066         return device_attach(&device->dev);
2067 }
2068 EXPORT_SYMBOL_GPL(acpi_bus_register_early_device);
2069
2070 static int acpi_bus_scan_fixed(void)
2071 {
2072         int result = 0;
2073
2074         /*
2075          * Enumerate all fixed-feature devices.
2076          */
2077         if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2078                 struct acpi_device *device = NULL;
2079
2080                 result = acpi_add_single_object(&device, NULL,
2081                                                 ACPI_BUS_TYPE_POWER_BUTTON,
2082                                                 ACPI_STA_DEFAULT);
2083                 if (result)
2084                         return result;
2085
2086                 device->flags.match_driver = true;
2087                 result = device_attach(&device->dev);
2088                 if (result < 0)
2089                         return result;
2090
2091                 device_init_wakeup(&device->dev, true);
2092         }
2093
2094         if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2095                 struct acpi_device *device = NULL;
2096
2097                 result = acpi_add_single_object(&device, NULL,
2098                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
2099                                                 ACPI_STA_DEFAULT);
2100                 if (result)
2101                         return result;
2102
2103                 device->flags.match_driver = true;
2104                 result = device_attach(&device->dev);
2105         }
2106
2107         return result < 0 ? result : 0;
2108 }
2109
2110 static void __init acpi_get_spcr_uart_addr(void)
2111 {
2112         acpi_status status;
2113         struct acpi_table_spcr *spcr_ptr;
2114
2115         status = acpi_get_table(ACPI_SIG_SPCR, 0,
2116                                 (struct acpi_table_header **)&spcr_ptr);
2117         if (ACPI_SUCCESS(status))
2118                 spcr_uart_addr = spcr_ptr->serial_port.address;
2119         else
2120                 printk(KERN_WARNING PREFIX "STAO table present, but SPCR is missing\n");
2121 }
2122
2123 static bool acpi_scan_initialized;
2124
2125 int __init acpi_scan_init(void)
2126 {
2127         int result;
2128         acpi_status status;
2129         struct acpi_table_stao *stao_ptr;
2130
2131         acpi_pci_root_init();
2132         acpi_pci_link_init();
2133         acpi_processor_init();
2134         acpi_lpss_init();
2135         acpi_apd_init();
2136         acpi_cmos_rtc_init();
2137         acpi_container_init();
2138         acpi_memory_hotplug_init();
2139         acpi_pnp_init();
2140         acpi_int340x_thermal_init();
2141         acpi_amba_init();
2142         acpi_watchdog_init();
2143         acpi_init_lpit();
2144
2145         acpi_scan_add_handler(&generic_device_handler);
2146
2147         /*
2148          * If there is STAO table, check whether it needs to ignore the UART
2149          * device in SPCR table.
2150          */
2151         status = acpi_get_table(ACPI_SIG_STAO, 0,
2152                                 (struct acpi_table_header **)&stao_ptr);
2153         if (ACPI_SUCCESS(status)) {
2154                 if (stao_ptr->header.length > sizeof(struct acpi_table_stao))
2155                         printk(KERN_INFO PREFIX "STAO Name List not yet supported.");
2156
2157                 if (stao_ptr->ignore_uart)
2158                         acpi_get_spcr_uart_addr();
2159         }
2160
2161         acpi_gpe_apply_masked_gpes();
2162         acpi_update_all_gpes();
2163
2164         mutex_lock(&acpi_scan_lock);
2165         /*
2166          * Enumerate devices in the ACPI namespace.
2167          */
2168         result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2169         if (result)
2170                 goto out;
2171
2172         result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2173         if (result)
2174                 goto out;
2175
2176         /* Fixed feature devices do not exist on HW-reduced platform */
2177         if (!acpi_gbl_reduced_hardware) {
2178                 result = acpi_bus_scan_fixed();
2179                 if (result) {
2180                         acpi_detach_data(acpi_root->handle,
2181                                          acpi_scan_drop_device);
2182                         acpi_device_del(acpi_root);
2183                         put_device(&acpi_root->dev);
2184                         goto out;
2185                 }
2186         }
2187
2188         acpi_scan_initialized = true;
2189
2190  out:
2191         mutex_unlock(&acpi_scan_lock);
2192         return result;
2193 }
2194
2195 static struct acpi_probe_entry *ape;
2196 static int acpi_probe_count;
2197 static DEFINE_MUTEX(acpi_probe_mutex);
2198
2199 static int __init acpi_match_madt(struct acpi_subtable_header *header,
2200                                   const unsigned long end)
2201 {
2202         if (!ape->subtable_valid || ape->subtable_valid(header, ape))
2203                 if (!ape->probe_subtbl(header, end))
2204                         acpi_probe_count++;
2205
2206         return 0;
2207 }
2208
2209 int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr)
2210 {
2211         int count = 0;
2212
2213         if (acpi_disabled)
2214                 return 0;
2215
2216         mutex_lock(&acpi_probe_mutex);
2217         for (ape = ap_head; nr; ape++, nr--) {
2218                 if (ACPI_COMPARE_NAME(ACPI_SIG_MADT, ape->id)) {
2219                         acpi_probe_count = 0;
2220                         acpi_table_parse_madt(ape->type, acpi_match_madt, 0);
2221                         count += acpi_probe_count;
2222                 } else {
2223                         int res;
2224                         res = acpi_table_parse(ape->id, ape->probe_table);
2225                         if (!res)
2226                                 count++;
2227                 }
2228         }
2229         mutex_unlock(&acpi_probe_mutex);
2230
2231         return count;
2232 }
2233
2234 struct acpi_table_events_work {
2235         struct work_struct work;
2236         void *table;
2237         u32 event;
2238 };
2239
2240 static void acpi_table_events_fn(struct work_struct *work)
2241 {
2242         struct acpi_table_events_work *tew;
2243
2244         tew = container_of(work, struct acpi_table_events_work, work);
2245
2246         if (tew->event == ACPI_TABLE_EVENT_LOAD) {
2247                 acpi_scan_lock_acquire();
2248                 acpi_bus_scan(ACPI_ROOT_OBJECT);
2249                 acpi_scan_lock_release();
2250         }
2251
2252         kfree(tew);
2253 }
2254
2255 void acpi_scan_table_handler(u32 event, void *table, void *context)
2256 {
2257         struct acpi_table_events_work *tew;
2258
2259         if (!acpi_scan_initialized)
2260                 return;
2261
2262         if (event != ACPI_TABLE_EVENT_LOAD)
2263                 return;
2264
2265         tew = kmalloc(sizeof(*tew), GFP_KERNEL);
2266         if (!tew)
2267                 return;
2268
2269         INIT_WORK(&tew->work, acpi_table_events_fn);
2270         tew->table = table;
2271         tew->event = event;
2272
2273         schedule_work(&tew->work);
2274 }
2275
2276 int acpi_reconfig_notifier_register(struct notifier_block *nb)
2277 {
2278         return blocking_notifier_chain_register(&acpi_reconfig_chain, nb);
2279 }
2280 EXPORT_SYMBOL(acpi_reconfig_notifier_register);
2281
2282 int acpi_reconfig_notifier_unregister(struct notifier_block *nb)
2283 {
2284         return blocking_notifier_chain_unregister(&acpi_reconfig_chain, nb);
2285 }
2286 EXPORT_SYMBOL(acpi_reconfig_notifier_unregister);