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
  17 #include <asm/pgtable.h>
  18
  19 #include "internal.h"
  20
  21 #define _COMPONENT              ACPI_BUS_COMPONENT
  22 ACPI_MODULE_NAME("scan");
  23 extern struct acpi_device *acpi_root;
  24
  25 #define ACPI_BUS_CLASS                  "system_bus"
  26 #define ACPI_BUS_HID                    "LNXSYBUS"
  27 #define ACPI_BUS_DEVICE_NAME            "System Bus"
  28
  29 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
  30
  31 #define INVALID_ACPI_HANDLE     ((acpi_handle)empty_zero_page)
  32
  33 static const char *dummy_hid = "device";
  34
  35 static LIST_HEAD(acpi_dep_list);
  36 static DEFINE_MUTEX(acpi_dep_list_lock);
  37 LIST_HEAD(acpi_bus_id_list);
  38 static DEFINE_MUTEX(acpi_scan_lock);
  39 static LIST_HEAD(acpi_scan_handlers_list);
  40 DEFINE_MUTEX(acpi_device_lock);
  41 LIST_HEAD(acpi_wakeup_device_list);
  42 static DEFINE_MUTEX(acpi_hp_context_lock);
  43
  44 /*
  45  * The UART device described by the SPCR table is the only object which needs
  46  * special-casing. Everything else is covered by ACPI namespace paths in STAO
  47  * table.
  48  */
  49 static u64 spcr_uart_addr;
  50
  51 struct acpi_dep_data {
  52         struct list_head node;
  53         acpi_handle master;
  54         acpi_handle slave;
  55 };
  56
  57 void acpi_scan_lock_acquire(void)
  58 {
  59         mutex_lock(&acpi_scan_lock);
  60 }
  61 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
  62
  63 void acpi_scan_lock_release(void)
  64 {
  65         mutex_unlock(&acpi_scan_lock);
  66 }
  67 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
  68
  69 void acpi_lock_hp_context(void)
  70 {
  71         mutex_lock(&acpi_hp_context_lock);
  72 }
  73
  74 void acpi_unlock_hp_context(void)
  75 {
  76         mutex_unlock(&acpi_hp_context_lock);
  77 }
  78
  79 void acpi_initialize_hp_context(struct acpi_device *adev,
  80                                 struct acpi_hotplug_context *hp,
  81                                 int (*notify)(struct acpi_device *, u32),
  82                                 void (*uevent)(struct acpi_device *, u32))
  83 {
  84         acpi_lock_hp_context();
  85         hp->notify = notify;
  86         hp->uevent = uevent;
  87         acpi_set_hp_context(adev, hp);
  88         acpi_unlock_hp_context();
  89 }
  90 EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
  91
  92 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
  93 {
  94         if (!handler)
  95                 return -EINVAL;
  96
  97         list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
  98         return 0;
  99 }
 100
 101 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
 102                                        const char *hotplug_profile_name)
 103 {
 104         int error;
 105
 106         error = acpi_scan_add_handler(handler);
 107         if (error)
 108                 return error;
 109
 110         acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
 111         return 0;
 112 }
 113
 114 bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
 115 {
 116         struct acpi_device_physical_node *pn;
 117         bool offline = true;
 118
 119         /*
 120          * acpi_container_offline() calls this for all of the container's
 121          * children under the container's physical_node_lock lock.
 122          */
 123         mutex_lock_nested(&adev->physical_node_lock, SINGLE_DEPTH_NESTING);
 124
 125         list_for_each_entry(pn, &adev->physical_node_list, node)
 126                 if (device_supports_offline(pn->dev) && !pn->dev->offline) {
 127                         if (uevent)
 128                                 kobject_uevent(&pn->dev->kobj, KOBJ_CHANGE);
 129
 130                         offline = false;
 131                         break;
 132                 }
 133
 134         mutex_unlock(&adev->physical_node_lock);
 135         return offline;
 136 }
 137
 138 static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
 139                                     void **ret_p)
 140 {
 141         struct acpi_device *device = NULL;
 142         struct acpi_device_physical_node *pn;
 143         bool second_pass = (bool)data;
 144         acpi_status status = AE_OK;
 145
 146         if (acpi_bus_get_device(handle, &device))
 147                 return AE_OK;
 148
 149         if (device->handler && !device->handler->hotplug.enabled) {
 150                 *ret_p = &device->dev;
 151                 return AE_SUPPORT;
 152         }
 153
 154         mutex_lock(&device->physical_node_lock);
 155
 156         list_for_each_entry(pn, &device->physical_node_list, node) {
 157                 int ret;
 158
 159                 if (second_pass) {
 160                         /* Skip devices offlined by the first pass. */
 161                         if (pn->put_online)
 162                                 continue;
 163                 } else {
 164                         pn->put_online = false;
 165                 }
 166                 ret = device_offline(pn->dev);
 167                 if (ret >= 0) {
 168                         pn->put_online = !ret;
 169                 } else {
 170                         *ret_p = pn->dev;
 171                         if (second_pass) {
 172                                 status = AE_ERROR;
 173                                 break;
 174                         }
 175                 }
 176         }
 177
 178         mutex_unlock(&device->physical_node_lock);
 179
 180         return status;
 181 }
 182
 183 static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
 184                                    void **ret_p)
 185 {
 186         struct acpi_device *device = NULL;
 187         struct acpi_device_physical_node *pn;
 188
 189         if (acpi_bus_get_device(handle, &device))
 190                 return AE_OK;
 191
 192         mutex_lock(&device->physical_node_lock);
 193
 194         list_for_each_entry(pn, &device->physical_node_list, node)
 195                 if (pn->put_online) {
 196                         device_online(pn->dev);
 197                         pn->put_online = false;
 198                 }
 199
 200         mutex_unlock(&device->physical_node_lock);
 201
 202         return AE_OK;
 203 }
 204
 205 static int acpi_scan_try_to_offline(struct acpi_device *device)
 206 {
 207         acpi_handle handle = device->handle;
 208         struct device *errdev = NULL;
 209         acpi_status status;
 210
 211         /*
 212          * Carry out two passes here and ignore errors in the first pass,
 213          * because if the devices in question are memory blocks and
 214          * CONFIG_MEMCG is set, one of the blocks may hold data structures
 215          * that the other blocks depend on, but it is not known in advance which
 216          * block holds them.
 217          *
 218          * If the first pass is successful, the second one isn't needed, though.
 219          */
 220         status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 221                                      NULL, acpi_bus_offline, (void *)false,
 222                                      (void **)&errdev);
 223         if (status == AE_SUPPORT) {
 224                 dev_warn(errdev, "Offline disabled.\n");
 225                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 226                                     acpi_bus_online, NULL, NULL, NULL);
 227                 return -EPERM;
 228         }
 229         acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
 230         if (errdev) {
 231                 errdev = NULL;
 232                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 233                                     NULL, acpi_bus_offline, (void *)true,
 234                                     (void **)&errdev);
 235                 if (!errdev)
 236                         acpi_bus_offline(handle, 0, (void *)true,
 237                                          (void **)&errdev);
 238
 239                 if (errdev) {
 240                         dev_warn(errdev, "Offline failed.\n");
 241                         acpi_bus_online(handle, 0, NULL, NULL);
 242                         acpi_walk_namespace(ACPI_TYPE_ANY, handle,
 243                                             ACPI_UINT32_MAX, acpi_bus_online,
 244                                             NULL, NULL, NULL);
 245                         return -EBUSY;
 246                 }
 247         }
 248         return 0;
 249 }
 250
 251 static int acpi_scan_hot_remove(struct acpi_device *device)
 252 {
 253         acpi_handle handle = device->handle;
 254         unsigned long long sta;
 255         acpi_status status;
 256
 257         if (device->handler && device->handler->hotplug.demand_offline) {
 258                 if (!acpi_scan_is_offline(device, true))
 259                         return -EBUSY;
 260         } else {
 261                 int error = acpi_scan_try_to_offline(device);
 262                 if (error)
 263                         return error;
 264         }
 265
 266         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 267                 "Hot-removing device %s...\n", dev_name(&device->dev)));
 268
 269         acpi_bus_trim(device);
 270
 271         acpi_evaluate_lck(handle, 0);
 272         /*
 273          * TBD: _EJD support.
 274          */
 275         status = acpi_evaluate_ej0(handle);
 276         if (status == AE_NOT_FOUND)
 277                 return -ENODEV;
 278         else if (ACPI_FAILURE(status))
 279                 return -EIO;
 280
 281         /*
 282          * Verify if eject was indeed successful.  If not, log an error
 283          * message.  No need to call _OST since _EJ0 call was made OK.
 284          */
 285         status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
 286         if (ACPI_FAILURE(status)) {
 287                 acpi_handle_warn(handle,
 288                         "Status check after eject failed (0x%x)\n", status);
 289         } else if (sta & ACPI_STA_DEVICE_ENABLED) {
 290                 acpi_handle_warn(handle,
 291                         "Eject incomplete - status 0x%llx\n", sta);
 292         }
 293
 294         return 0;
 295 }
 296
 297 static int acpi_scan_device_not_present(struct acpi_device *adev)
 298 {
 299         if (!acpi_device_enumerated(adev)) {
 300                 dev_warn(&adev->dev, "Still not present\n");
 301                 return -EALREADY;
 302         }
 303         acpi_bus_trim(adev);
 304         return 0;
 305 }
 306
 307 static int acpi_scan_device_check(struct acpi_device *adev)
 308 {
 309         int error;
 310
 311         acpi_bus_get_status(adev);
 312         if (adev->status.present || adev->status.functional) {
 313                 /*
 314                  * This function is only called for device objects for which
 315                  * matching scan handlers exist.  The only situation in which
 316                  * the scan handler is not attached to this device object yet
 317                  * is when the device has just appeared (either it wasn't
 318                  * present at all before or it was removed and then added
 319                  * again).
 320                  */
 321                 if (adev->handler) {
 322                         dev_warn(&adev->dev, "Already enumerated\n");
 323                         return -EALREADY;
 324                 }
 325                 error = acpi_bus_scan(adev->handle);
 326                 if (error) {
 327                         dev_warn(&adev->dev, "Namespace scan failure\n");
 328                         return error;
 329                 }
 330                 if (!adev->handler) {
 331                         dev_warn(&adev->dev, "Enumeration failure\n");
 332                         error = -ENODEV;
 333                 }
 334         } else {
 335                 error = acpi_scan_device_not_present(adev);
 336         }
 337         return error;
 338 }
 339
 340 static int acpi_scan_bus_check(struct acpi_device *adev)
 341 {
 342         struct acpi_scan_handler *handler = adev->handler;
 343         struct acpi_device *child;
 344         int error;
 345
 346         acpi_bus_get_status(adev);
 347         if (!(adev->status.present || adev->status.functional)) {
 348                 acpi_scan_device_not_present(adev);
 349                 return 0;
 350         }
 351         if (handler && handler->hotplug.scan_dependent)
 352                 return handler->hotplug.scan_dependent(adev);
 353
 354         error = acpi_bus_scan(adev->handle);
 355         if (error) {
 356                 dev_warn(&adev->dev, "Namespace scan failure\n");
 357                 return error;
 358         }
 359         list_for_each_entry(child, &adev->children, node) {
 360                 error = acpi_scan_bus_check(child);
 361                 if (error)
 362                         return error;
 363         }
 364         return 0;
 365 }
 366
 367 static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type)
 368 {
 369         switch (type) {
 370         case ACPI_NOTIFY_BUS_CHECK:
 371                 return acpi_scan_bus_check(adev);
 372         case ACPI_NOTIFY_DEVICE_CHECK:
 373                 return acpi_scan_device_check(adev);
 374         case ACPI_NOTIFY_EJECT_REQUEST:
 375         case ACPI_OST_EC_OSPM_EJECT:
 376                 if (adev->handler && !adev->handler->hotplug.enabled) {
 377                         dev_info(&adev->dev, "Eject disabled\n");
 378                         return -EPERM;
 379                 }
 380                 acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST,
 381                                   ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
 382                 return acpi_scan_hot_remove(adev);
 383         }
 384         return -EINVAL;
 385 }
 386
 387 void acpi_device_hotplug(struct acpi_device *adev, u32 src)
 388 {
 389         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
 390         int error = -ENODEV;
 391
 392         lock_device_hotplug();
 393         mutex_lock(&acpi_scan_lock);
 394
 395         /*
 396          * The device object's ACPI handle cannot become invalid as long as we
 397          * are holding acpi_scan_lock, but it might have become invalid before
 398          * that lock was acquired.
 399          */
 400         if (adev->handle == INVALID_ACPI_HANDLE)
 401                 goto err_out;
 402
 403         if (adev->flags.is_dock_station) {
 404                 error = dock_notify(adev, src);
 405         } else if (adev->flags.hotplug_notify) {
 406                 error = acpi_generic_hotplug_event(adev, src);
 407                 if (error == -EPERM) {
 408                         ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
 409                         goto err_out;
 410                 }
 411         } else {
 412                 int (*notify)(struct acpi_device *, u32);
 413
 414                 acpi_lock_hp_context();
 415                 notify = adev->hp ? adev->hp->notify : NULL;
 416                 acpi_unlock_hp_context();
 417                 /*
 418                  * There may be additional notify handlers for device objects
 419                  * without the .event() callback, so ignore them here.
 420                  */
 421                 if (notify)
 422                         error = notify(adev, src);
 423                 else
 424                         goto out;
 425         }
 426         if (!error)
 427                 ost_code = ACPI_OST_SC_SUCCESS;
 428
 429  err_out:
 430         acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
 431
 432  out:
 433         acpi_bus_put_acpi_device(adev);
 434         mutex_unlock(&acpi_scan_lock);
 435         unlock_device_hotplug();
 436 }
 437
 438 static void acpi_free_power_resources_lists(struct acpi_device *device)
 439 {
 440         int i;
 441
 442         if (device->wakeup.flags.valid)
 443                 acpi_power_resources_list_free(&device->wakeup.resources);
 444
 445         if (!device->power.flags.power_resources)
 446                 return;
 447
 448         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
 449                 struct acpi_device_power_state *ps = &device->power.states[i];
 450                 acpi_power_resources_list_free(&ps->resources);
 451         }
 452 }
 453
 454 static void acpi_device_release(struct device *dev)
 455 {
 456         struct acpi_device *acpi_dev = to_acpi_device(dev);
 457
 458         acpi_free_properties(acpi_dev);
 459         acpi_free_pnp_ids(&acpi_dev->pnp);
 460         acpi_free_power_resources_lists(acpi_dev);
 461         kfree(acpi_dev);
 462 }
 463
 464 static void acpi_device_del(struct acpi_device *device)
 465 {
 466         struct acpi_device_bus_id *acpi_device_bus_id;
 467
 468         mutex_lock(&acpi_device_lock);
 469         if (device->parent)
 470                 list_del(&device->node);
 471
 472         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node)
 473                 if (!strcmp(acpi_device_bus_id->bus_id,
 474                             acpi_device_hid(device))) {
 475                         if (acpi_device_bus_id->instance_no > 0)
 476                                 acpi_device_bus_id->instance_no--;
 477                         else {
 478                                 list_del(&acpi_device_bus_id->node);
 479                                 kfree(acpi_device_bus_id);
 480                         }
 481                         break;
 482                 }
 483
 484         list_del(&device->wakeup_list);
 485         mutex_unlock(&acpi_device_lock);
 486
 487         acpi_power_add_remove_device(device, false);
 488         acpi_device_remove_files(device);
 489         if (device->remove)
 490                 device->remove(device);
 491
 492         device_del(&device->dev);
 493 }
 494
 495 static BLOCKING_NOTIFIER_HEAD(acpi_reconfig_chain);
 496
 497 static LIST_HEAD(acpi_device_del_list);
 498 static DEFINE_MUTEX(acpi_device_del_lock);
 499
 500 static void acpi_device_del_work_fn(struct work_struct *work_not_used)
 501 {
 502         for (;;) {
 503                 struct acpi_device *adev;
 504
 505                 mutex_lock(&acpi_device_del_lock);
 506
 507                 if (list_empty(&acpi_device_del_list)) {
 508                         mutex_unlock(&acpi_device_del_lock);
 509                         break;
 510                 }
 511                 adev = list_first_entry(&acpi_device_del_list,
 512                                         struct acpi_device, del_list);
 513                 list_del(&adev->del_list);
 514
 515                 mutex_unlock(&acpi_device_del_lock);
 516
 517                 blocking_notifier_call_chain(&acpi_reconfig_chain,
 518                                              ACPI_RECONFIG_DEVICE_REMOVE, adev);
 519
 520                 acpi_device_del(adev);
 521                 /*
 522                  * Drop references to all power resources that might have been
 523                  * used by the device.
 524                  */
 525                 acpi_power_transition(adev, ACPI_STATE_D3_COLD);
 526                 put_device(&adev->dev);
 527         }
 528 }
 529
 530 /**
 531  * acpi_scan_drop_device - Drop an ACPI device object.
 532  * @handle: Handle of an ACPI namespace node, not used.
 533  * @context: Address of the ACPI device object to drop.
 534  *
 535  * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
 536  * namespace node the device object pointed to by @context is attached to.
 537  *
 538  * The unregistration is carried out asynchronously to avoid running
 539  * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
 540  * ensure the correct ordering (the device objects must be unregistered in the
 541  * same order in which the corresponding namespace nodes are deleted).
 542  */
 543 static void acpi_scan_drop_device(acpi_handle handle, void *context)
 544 {
 545         static DECLARE_WORK(work, acpi_device_del_work_fn);
 546         struct acpi_device *adev = context;
 547
 548         mutex_lock(&acpi_device_del_lock);
 549
 550         /*
 551          * Use the ACPI hotplug workqueue which is ordered, so this work item
 552          * won't run after any hotplug work items submitted subsequently.  That
 553          * prevents attempts to register device objects identical to those being
 554          * deleted from happening concurrently (such attempts result from
 555          * hotplug events handled via the ACPI hotplug workqueue).  It also will
 556          * run after all of the work items submitted previosuly, which helps
 557          * those work items to ensure that they are not accessing stale device
 558          * objects.
 559          */
 560         if (list_empty(&acpi_device_del_list))
 561                 acpi_queue_hotplug_work(&work);
 562
 563         list_add_tail(&adev->del_list, &acpi_device_del_list);
 564         /* Make acpi_ns_validate_handle() return NULL for this handle. */
 565         adev->handle = INVALID_ACPI_HANDLE;
 566
 567         mutex_unlock(&acpi_device_del_lock);
 568 }
 569
 570 static int acpi_get_device_data(acpi_handle handle, struct acpi_device **device,
 571                                 void (*callback)(void *))
 572 {
 573         acpi_status status;
 574
 575         if (!device)
 576                 return -EINVAL;
 577
 578         status = acpi_get_data_full(handle, acpi_scan_drop_device,
 579                                     (void **)device, callback);
 580         if (ACPI_FAILURE(status) || !*device) {
 581                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
 582                                   handle));
 583                 return -ENODEV;
 584         }
 585         return 0;
 586 }
 587
 588 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
 589 {
 590         return acpi_get_device_data(handle, device, NULL);
 591 }
 592 EXPORT_SYMBOL(acpi_bus_get_device);
 593
 594 static void get_acpi_device(void *dev)
 595 {
 596         if (dev)
 597                 get_device(&((struct acpi_device *)dev)->dev);
 598 }
 599
 600 struct acpi_device *acpi_bus_get_acpi_device(acpi_handle handle)
 601 {
 602         struct acpi_device *adev = NULL;
 603
 604         acpi_get_device_data(handle, &adev, get_acpi_device);
 605         return adev;
 606 }
 607
 608 void acpi_bus_put_acpi_device(struct acpi_device *adev)
 609 {
 610         put_device(&adev->dev);
 611 }
 612
 613 int acpi_device_add(struct acpi_device *device,
 614                     void (*release)(struct device *))
 615 {
 616         int result;
 617         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
 618         int found = 0;
 619
 620         if (device->handle) {
 621                 acpi_status status;
 622
 623                 status = acpi_attach_data(device->handle, acpi_scan_drop_device,
 624                                           device);
 625                 if (ACPI_FAILURE(status)) {
 626                         acpi_handle_err(device->handle,
 627                                         "Unable to attach device data\n");
 628                         return -ENODEV;
 629                 }
 630         }
 631
 632         /*
 633          * Linkage
 634          * -------
 635          * Link this device to its parent and siblings.
 636          */
 637         INIT_LIST_HEAD(&device->children);
 638         INIT_LIST_HEAD(&device->node);
 639         INIT_LIST_HEAD(&device->wakeup_list);
 640         INIT_LIST_HEAD(&device->physical_node_list);
 641         INIT_LIST_HEAD(&device->del_list);
 642         mutex_init(&device->physical_node_lock);
 643
 644         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
 645         if (!new_bus_id) {
 646                 pr_err(PREFIX "Memory allocation error\n");
 647                 result = -ENOMEM;
 648                 goto err_detach;
 649         }
 650
 651         mutex_lock(&acpi_device_lock);
 652         /*
 653          * Find suitable bus_id and instance number in acpi_bus_id_list
 654          * If failed, create one and link it into acpi_bus_id_list
 655          */
 656         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
 657                 if (!strcmp(acpi_device_bus_id->bus_id,
 658                             acpi_device_hid(device))) {
 659                         acpi_device_bus_id->instance_no++;
 660                         found = 1;
 661                         kfree(new_bus_id);
 662                         break;
 663                 }
 664         }
 665         if (!found) {
 666                 acpi_device_bus_id = new_bus_id;
 667                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
 668                 acpi_device_bus_id->instance_no = 0;
 669                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
 670         }
 671         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
 672
 673         if (device->parent)
 674                 list_add_tail(&device->node, &device->parent->children);
 675
 676         if (device->wakeup.flags.valid)
 677                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
 678         mutex_unlock(&acpi_device_lock);
 679
 680         if (device->parent)
 681                 device->dev.parent = &device->parent->dev;
 682         device->dev.bus = &acpi_bus_type;
 683         device->dev.release = release;
 684         result = device_add(&device->dev);
 685         if (result) {
 686                 dev_err(&device->dev, "Error registering device\n");
 687                 goto err;
 688         }
 689
 690         result = acpi_device_setup_files(device);
 691         if (result)
 692                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
 693                        dev_name(&device->dev));
 694
 695         return 0;
 696
 697  err:
 698         mutex_lock(&acpi_device_lock);
 699         if (device->parent)
 700                 list_del(&device->node);
 701         list_del(&device->wakeup_list);
 702         mutex_unlock(&acpi_device_lock);
 703
 704  err_detach:
 705         acpi_detach_data(device->handle, acpi_scan_drop_device);
 706         return result;
 707 }
 708
 709 /* --------------------------------------------------------------------------
 710                                  Device Enumeration
 711    -------------------------------------------------------------------------- */
 712 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
 713 {
 714         struct acpi_device *device = NULL;
 715         acpi_status status;
 716
 717         /*
 718          * Fixed hardware devices do not appear in the namespace and do not
 719          * have handles, but we fabricate acpi_devices for them, so we have
 720          * to deal with them specially.
 721          */
 722         if (!handle)
 723                 return acpi_root;
 724
 725         do {
 726                 status = acpi_get_parent(handle, &handle);
 727                 if (ACPI_FAILURE(status))
 728                         return status == AE_NULL_ENTRY ? NULL : acpi_root;
 729         } while (acpi_bus_get_device(handle, &device));
 730         return device;
 731 }
 732
 733 acpi_status
 734 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
 735 {
 736         acpi_status status;
 737         acpi_handle tmp;
 738         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 739         union acpi_object *obj;
 740
 741         status = acpi_get_handle(handle, "_EJD", &tmp);
 742         if (ACPI_FAILURE(status))
 743                 return status;
 744
 745         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
 746         if (ACPI_SUCCESS(status)) {
 747                 obj = buffer.pointer;
 748                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
 749                                          ejd);
 750                 kfree(buffer.pointer);
 751         }
 752         return status;
 753 }
 754 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
 755
 756 static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
 757                                         struct acpi_device_wakeup *wakeup)
 758 {
 759         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 760         union acpi_object *package = NULL;
 761         union acpi_object *element = NULL;
 762         acpi_status status;
 763         int err = -ENODATA;
 764
 765         if (!wakeup)
 766                 return -EINVAL;
 767
 768         INIT_LIST_HEAD(&wakeup->resources);
 769
 770         /* _PRW */
 771         status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
 772         if (ACPI_FAILURE(status)) {
 773                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
 774                 return err;
 775         }
 776
 777         package = (union acpi_object *)buffer.pointer;
 778
 779         if (!package || package->package.count < 2)
 780                 goto out;
 781
 782         element = &(package->package.elements[0]);
 783         if (!element)
 784                 goto out;
 785
 786         if (element->type == ACPI_TYPE_PACKAGE) {
 787                 if ((element->package.count < 2) ||
 788                     (element->package.elements[0].type !=
 789                      ACPI_TYPE_LOCAL_REFERENCE)
 790                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
 791                         goto out;
 792
 793                 wakeup->gpe_device =
 794                     element->package.elements[0].reference.handle;
 795                 wakeup->gpe_number =
 796                     (u32) element->package.elements[1].integer.value;
 797         } else if (element->type == ACPI_TYPE_INTEGER) {
 798                 wakeup->gpe_device = NULL;
 799                 wakeup->gpe_number = element->integer.value;
 800         } else {
 801                 goto out;
 802         }
 803
 804         element = &(package->package.elements[1]);
 805         if (element->type != ACPI_TYPE_INTEGER)
 806                 goto out;
 807
 808         wakeup->sleep_state = element->integer.value;
 809
 810         err = acpi_extract_power_resources(package, 2, &wakeup->resources);
 811         if (err)
 812                 goto out;
 813
 814         if (!list_empty(&wakeup->resources)) {
 815                 int sleep_state;
 816
 817                 err = acpi_power_wakeup_list_init(&wakeup->resources,
 818                                                   &sleep_state);
 819                 if (err) {
 820                         acpi_handle_warn(handle, "Retrieving current states "
 821                                          "of wakeup power resources failed\n");
 822                         acpi_power_resources_list_free(&wakeup->resources);
 823                         goto out;
 824                 }
 825                 if (sleep_state < wakeup->sleep_state) {
 826                         acpi_handle_warn(handle, "Overriding _PRW sleep state "
 827                                          "(S%d) by S%d from power resources\n",
 828                                          (int)wakeup->sleep_state, sleep_state);
 829                         wakeup->sleep_state = sleep_state;
 830                 }
 831         }
 832
 833  out:
 834         kfree(buffer.pointer);
 835         return err;
 836 }
 837
 838 static void acpi_wakeup_gpe_init(struct acpi_device *device)
 839 {
 840         static const struct acpi_device_id button_device_ids[] = {
 841                 {"PNP0C0C", 0},
 842                 {"PNP0C0D", 0},
 843                 {"PNP0C0E", 0},
 844                 {"", 0},
 845         };
 846         struct acpi_device_wakeup *wakeup = &device->wakeup;
 847         acpi_status status;
 848         acpi_event_status event_status;
 849
 850         wakeup->flags.notifier_present = 0;
 851
 852         /* Power button, Lid switch always enable wakeup */
 853         if (!acpi_match_device_ids(device, button_device_ids)) {
 854                 wakeup->flags.run_wake = 1;
 855                 if (!acpi_match_device_ids(device, &button_device_ids[1])) {
 856                         /* Do not use Lid/sleep button for S5 wakeup */
 857                         if (wakeup->sleep_state == ACPI_STATE_S5)
 858                                 wakeup->sleep_state = ACPI_STATE_S4;
 859                 }
 860                 acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
 861                 device_set_wakeup_capable(&device->dev, true);
 862                 return;
 863         }
 864
 865         acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
 866                                 wakeup->gpe_number);
 867         status = acpi_get_gpe_status(wakeup->gpe_device, wakeup->gpe_number,
 868                                      &event_status);
 869         if (ACPI_FAILURE(status))
 870                 return;
 871
 872         wakeup->flags.run_wake = !!(event_status & ACPI_EVENT_FLAG_HAS_HANDLER);
 873 }
 874
 875 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
 876 {
 877         int err;
 878
 879         /* Presence of _PRW indicates wake capable */
 880         if (!acpi_has_method(device->handle, "_PRW"))
 881                 return;
 882
 883         err = acpi_bus_extract_wakeup_device_power_package(device->handle,
 884                                                            &device->wakeup);
 885         if (err) {
 886                 dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
 887                 return;
 888         }
 889
 890         device->wakeup.flags.valid = 1;
 891         device->wakeup.prepare_count = 0;
 892         acpi_wakeup_gpe_init(device);
 893         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
 894          * system for the ACPI device with the _PRW object.
 895          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
 896          * So it is necessary to call _DSW object first. Only when it is not
 897          * present will the _PSW object used.
 898          */
 899         err = acpi_device_sleep_wake(device, 0, 0, 0);
 900         if (err)
 901                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 902                                 "error in _DSW or _PSW evaluation\n"));
 903 }
 904
 905 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
 906 {
 907         struct acpi_device_power_state *ps = &device->power.states[state];
 908         char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
 909         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 910         acpi_status status;
 911
 912         INIT_LIST_HEAD(&ps->resources);
 913
 914         /* Evaluate "_PRx" to get referenced power resources */
 915         status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
 916         if (ACPI_SUCCESS(status)) {
 917                 union acpi_object *package = buffer.pointer;
 918
 919                 if (buffer.length && package
 920                     && package->type == ACPI_TYPE_PACKAGE
 921                     && package->package.count) {
 922                         int err = acpi_extract_power_resources(package, 0,
 923                                                                &ps->resources);
 924                         if (!err)
 925                                 device->power.flags.power_resources = 1;
 926                 }
 927                 ACPI_FREE(buffer.pointer);
 928         }
 929
 930         /* Evaluate "_PSx" to see if we can do explicit sets */
 931         pathname[2] = 'S';
 932         if (acpi_has_method(device->handle, pathname))
 933                 ps->flags.explicit_set = 1;
 934
 935         /* State is valid if there are means to put the device into it. */
 936         if (!list_empty(&ps->resources) || ps->flags.explicit_set)
 937                 ps->flags.valid = 1;
 938
 939         ps->power = -1;         /* Unknown - driver assigned */
 940         ps->latency = -1;       /* Unknown - driver assigned */
 941 }
 942
 943 static void acpi_bus_get_power_flags(struct acpi_device *device)
 944 {
 945         u32 i;
 946
 947         /* Presence of _PS0|_PR0 indicates 'power manageable' */
 948         if (!acpi_has_method(device->handle, "_PS0") &&
 949             !acpi_has_method(device->handle, "_PR0"))
 950                 return;
 951
 952         device->flags.power_manageable = 1;
 953
 954         /*
 955          * Power Management Flags
 956          */
 957         if (acpi_has_method(device->handle, "_PSC"))
 958                 device->power.flags.explicit_get = 1;
 959
 960         if (acpi_has_method(device->handle, "_IRC"))
 961                 device->power.flags.inrush_current = 1;
 962
 963         if (acpi_has_method(device->handle, "_DSW"))
 964                 device->power.flags.dsw_present = 1;
 965
 966         /*
 967          * Enumerate supported power management states
 968          */
 969         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
 970                 acpi_bus_init_power_state(device, i);
 971
 972         INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
 973         if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources))
 974                 device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
 975
 976         /* Set defaults for D0 and D3hot states (always valid) */
 977         device->power.states[ACPI_STATE_D0].flags.valid = 1;
 978         device->power.states[ACPI_STATE_D0].power = 100;
 979         device->power.states[ACPI_STATE_D3_HOT].flags.valid = 1;
 980
 981         if (acpi_bus_init_power(device))
 982                 device->flags.power_manageable = 0;
 983 }
 984
 985 static void acpi_bus_get_flags(struct acpi_device *device)
 986 {
 987         /* Presence of _STA indicates 'dynamic_status' */
 988         if (acpi_has_method(device->handle, "_STA"))
 989                 device->flags.dynamic_status = 1;
 990
 991         /* Presence of _RMV indicates 'removable' */
 992         if (acpi_has_method(device->handle, "_RMV"))
 993                 device->flags.removable = 1;
 994
 995         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
 996         if (acpi_has_method(device->handle, "_EJD") ||
 997             acpi_has_method(device->handle, "_EJ0"))
 998                 device->flags.ejectable = 1;
 999 }
1000
1001 static void acpi_device_get_busid(struct acpi_device *device)
1002 {
1003         char bus_id[5] = { '?', 0 };
1004         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1005         int i = 0;
1006
1007         /*
1008          * Bus ID
1009          * ------
1010          * The device's Bus ID is simply the object name.
1011          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1012          */
1013         if (ACPI_IS_ROOT_DEVICE(device)) {
1014                 strcpy(device->pnp.bus_id, "ACPI");
1015                 return;
1016         }
1017
1018         switch (device->device_type) {
1019         case ACPI_BUS_TYPE_POWER_BUTTON:
1020                 strcpy(device->pnp.bus_id, "PWRF");
1021                 break;
1022         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1023                 strcpy(device->pnp.bus_id, "SLPF");
1024                 break;
1025         default:
1026                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1027                 /* Clean up trailing underscores (if any) */
1028                 for (i = 3; i > 1; i--) {
1029                         if (bus_id[i] == '_')
1030                                 bus_id[i] = '\0';
1031                         else
1032                                 break;
1033                 }
1034                 strcpy(device->pnp.bus_id, bus_id);
1035                 break;
1036         }
1037 }
1038
1039 /*
1040  * acpi_ata_match - see if an acpi object is an ATA device
1041  *
1042  * If an acpi object has one of the ACPI ATA methods defined,
1043  * then we can safely call it an ATA device.
1044  */
1045 bool acpi_ata_match(acpi_handle handle)
1046 {
1047         return acpi_has_method(handle, "_GTF") ||
1048                acpi_has_method(handle, "_GTM") ||
1049                acpi_has_method(handle, "_STM") ||
1050                acpi_has_method(handle, "_SDD");
1051 }
1052
1053 /*
1054  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1055  *
1056  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1057  * then we can safely call it an ejectable drive bay
1058  */
1059 bool acpi_bay_match(acpi_handle handle)
1060 {
1061         acpi_handle phandle;
1062
1063         if (!acpi_has_method(handle, "_EJ0"))
1064                 return false;
1065         if (acpi_ata_match(handle))
1066                 return true;
1067         if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1068                 return false;
1069
1070         return acpi_ata_match(phandle);
1071 }
1072
1073 bool acpi_device_is_battery(struct acpi_device *adev)
1074 {
1075         struct acpi_hardware_id *hwid;
1076
1077         list_for_each_entry(hwid, &adev->pnp.ids, list)
1078                 if (!strcmp("PNP0C0A", hwid->id))
1079                         return true;
1080
1081         return false;
1082 }
1083
1084 static bool is_ejectable_bay(struct acpi_device *adev)
1085 {
1086         acpi_handle handle = adev->handle;
1087
1088         if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
1089                 return true;
1090
1091         return acpi_bay_match(handle);
1092 }
1093
1094 /*
1095  * acpi_dock_match - see if an acpi object has a _DCK method
1096  */
1097 bool acpi_dock_match(acpi_handle handle)
1098 {
1099         return acpi_has_method(handle, "_DCK");
1100 }
1101
1102 static acpi_status
1103 acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
1104                           void **return_value)
1105 {
1106         long *cap = context;
1107
1108         if (acpi_has_method(handle, "_BCM") &&
1109             acpi_has_method(handle, "_BCL")) {
1110                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight "
1111                                   "support\n"));
1112                 *cap |= ACPI_VIDEO_BACKLIGHT;
1113                 /* We have backlight support, no need to scan further */
1114                 return AE_CTRL_TERMINATE;
1115         }
1116         return 0;
1117 }
1118
1119 /* Returns true if the ACPI object is a video device which can be
1120  * handled by video.ko.
1121  * The device will get a Linux specific CID added in scan.c to
1122  * identify the device as an ACPI graphics device
1123  * Be aware that the graphics device may not be physically present
1124  * Use acpi_video_get_capabilities() to detect general ACPI video
1125  * capabilities of present cards
1126  */
1127 long acpi_is_video_device(acpi_handle handle)
1128 {
1129         long video_caps = 0;
1130
1131         /* Is this device able to support video switching ? */
1132         if (acpi_has_method(handle, "_DOD") || acpi_has_method(handle, "_DOS"))
1133                 video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
1134
1135         /* Is this device able to retrieve a video ROM ? */
1136         if (acpi_has_method(handle, "_ROM"))
1137                 video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
1138
1139         /* Is this device able to configure which video head to be POSTed ? */
1140         if (acpi_has_method(handle, "_VPO") &&
1141             acpi_has_method(handle, "_GPD") &&
1142             acpi_has_method(handle, "_SPD"))
1143                 video_caps |= ACPI_VIDEO_DEVICE_POSTING;
1144
1145         /* Only check for backlight functionality if one of the above hit. */
1146         if (video_caps)
1147                 acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
1148                                     ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
1149                                     &video_caps, NULL);
1150
1151         return video_caps;
1152 }
1153 EXPORT_SYMBOL(acpi_is_video_device);
1154
1155 const char *acpi_device_hid(struct acpi_device *device)
1156 {
1157         struct acpi_hardware_id *hid;
1158
1159         if (list_empty(&device->pnp.ids))
1160                 return dummy_hid;
1161
1162         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1163         return hid->id;
1164 }
1165 EXPORT_SYMBOL(acpi_device_hid);
1166
1167 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1168 {
1169         struct acpi_hardware_id *id;
1170
1171         id = kmalloc(sizeof(*id), GFP_KERNEL);
1172         if (!id)
1173                 return;
1174
1175         id->id = kstrdup_const(dev_id, GFP_KERNEL);
1176         if (!id->id) {
1177                 kfree(id);
1178                 return;
1179         }
1180
1181         list_add_tail(&id->list, &pnp->ids);
1182         pnp->type.hardware_id = 1;
1183 }
1184
1185 /*
1186  * Old IBM workstations have a DSDT bug wherein the SMBus object
1187  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1188  * prefix.  Work around this.
1189  */
1190 static bool acpi_ibm_smbus_match(acpi_handle handle)
1191 {
1192         char node_name[ACPI_PATH_SEGMENT_LENGTH];
1193         struct acpi_buffer path = { sizeof(node_name), node_name };
1194
1195         if (!dmi_name_in_vendors("IBM"))
1196                 return false;
1197
1198         /* Look for SMBS object */
1199         if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1200             strcmp("SMBS", path.pointer))
1201                 return false;
1202
1203         /* Does it have the necessary (but misnamed) methods? */
1204         if (acpi_has_method(handle, "SBI") &&
1205             acpi_has_method(handle, "SBR") &&
1206             acpi_has_method(handle, "SBW"))
1207                 return true;
1208
1209         return false;
1210 }
1211
1212 static bool acpi_object_is_system_bus(acpi_handle handle)
1213 {
1214         acpi_handle tmp;
1215
1216         if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
1217             tmp == handle)
1218                 return true;
1219         if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
1220             tmp == handle)
1221                 return true;
1222
1223         return false;
1224 }
1225
1226 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1227                                 int device_type)
1228 {
1229         acpi_status status;
1230         struct acpi_device_info *info;
1231         struct acpi_pnp_device_id_list *cid_list;
1232         int i;
1233
1234         switch (device_type) {
1235         case ACPI_BUS_TYPE_DEVICE:
1236                 if (handle == ACPI_ROOT_OBJECT) {
1237                         acpi_add_id(pnp, ACPI_SYSTEM_HID);
1238                         break;
1239                 }
1240
1241                 status = acpi_get_object_info(handle, &info);
1242                 if (ACPI_FAILURE(status)) {
1243                         pr_err(PREFIX "%s: Error reading device info\n",
1244                                         __func__);
1245                         return;
1246                 }
1247
1248                 if (info->valid & ACPI_VALID_HID) {
1249                         acpi_add_id(pnp, info->hardware_id.string);
1250                         pnp->type.platform_id = 1;
1251                 }
1252                 if (info->valid & ACPI_VALID_CID) {
1253                         cid_list = &info->compatible_id_list;
1254                         for (i = 0; i < cid_list->count; i++)
1255                                 acpi_add_id(pnp, cid_list->ids[i].string);
1256                 }
1257                 if (info->valid & ACPI_VALID_ADR) {
1258                         pnp->bus_address = info->address;
1259                         pnp->type.bus_address = 1;
1260                 }
1261                 if (info->valid & ACPI_VALID_UID)
1262                         pnp->unique_id = kstrdup(info->unique_id.string,
1263                                                         GFP_KERNEL);
1264                 if (info->valid & ACPI_VALID_CLS)
1265                         acpi_add_id(pnp, info->class_code.string);
1266
1267                 kfree(info);
1268
1269                 /*
1270                  * Some devices don't reliably have _HIDs & _CIDs, so add
1271                  * synthetic HIDs to make sure drivers can find them.
1272                  */
1273                 if (acpi_is_video_device(handle))
1274                         acpi_add_id(pnp, ACPI_VIDEO_HID);
1275                 else if (acpi_bay_match(handle))
1276                         acpi_add_id(pnp, ACPI_BAY_HID);
1277                 else if (acpi_dock_match(handle))
1278                         acpi_add_id(pnp, ACPI_DOCK_HID);
1279                 else if (acpi_ibm_smbus_match(handle))
1280                         acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1281                 else if (list_empty(&pnp->ids) &&
1282                          acpi_object_is_system_bus(handle)) {
1283                         /* \_SB, \_TZ, LNXSYBUS */
1284                         acpi_add_id(pnp, ACPI_BUS_HID);
1285                         strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1286                         strcpy(pnp->device_class, ACPI_BUS_CLASS);
1287                 }
1288
1289                 break;
1290         case ACPI_BUS_TYPE_POWER:
1291                 acpi_add_id(pnp, ACPI_POWER_HID);
1292                 break;
1293         case ACPI_BUS_TYPE_PROCESSOR:
1294                 acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1295                 break;
1296         case ACPI_BUS_TYPE_THERMAL:
1297                 acpi_add_id(pnp, ACPI_THERMAL_HID);
1298                 break;
1299         case ACPI_BUS_TYPE_POWER_BUTTON:
1300                 acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1301                 break;
1302         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1303                 acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1304                 break;
1305         }
1306 }
1307
1308 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1309 {
1310         struct acpi_hardware_id *id, *tmp;
1311
1312         list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1313                 kfree_const(id->id);
1314                 kfree(id);
1315         }
1316         kfree(pnp->unique_id);
1317 }
1318
1319 /**
1320  * acpi_dma_supported - Check DMA support for the specified device.
1321  * @adev: The pointer to acpi device
1322  *
1323  * Return false if DMA is not supported. Otherwise, return true
1324  */
1325 bool acpi_dma_supported(struct acpi_device *adev)
1326 {
1327         if (!adev)
1328                 return false;
1329
1330         if (adev->flags.cca_seen)
1331                 return true;
1332
1333         /*
1334         * Per ACPI 6.0 sec 6.2.17, assume devices can do cache-coherent
1335         * DMA on "Intel platforms".  Presumably that includes all x86 and
1336         * ia64, and other arches will set CONFIG_ACPI_CCA_REQUIRED=y.
1337         */
1338         if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1339                 return true;
1340
1341         return false;
1342 }
1343
1344 /**
1345  * acpi_get_dma_attr - Check the supported DMA attr for the specified device.
1346  * @adev: The pointer to acpi device
1347  *
1348  * Return enum dev_dma_attr.
1349  */
1350 enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
1351 {
1352         if (!acpi_dma_supported(adev))
1353                 return DEV_DMA_NOT_SUPPORTED;
1354
1355         if (adev->flags.coherent_dma)
1356                 return DEV_DMA_COHERENT;
1357         else
1358                 return DEV_DMA_NON_COHERENT;
1359 }
1360
1361 /**
1362  * acpi_dma_configure - Set-up DMA configuration for the device.
1363  * @dev: The pointer to the device
1364  * @attr: device dma attributes
1365  */
1366 int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr)
1367 {
1368         const struct iommu_ops *iommu;
1369         u64 size;
1370
1371         iort_set_dma_mask(dev);
1372
1373         iommu = iort_iommu_configure(dev);
1374         if (IS_ERR(iommu) && PTR_ERR(iommu) == -EPROBE_DEFER)
1375                 return -EPROBE_DEFER;
1376
1377         size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1);
1378         /*
1379          * Assume dma valid range starts at 0 and covers the whole
1380          * coherent_dma_mask.
1381          */
1382         arch_setup_dma_ops(dev, 0, size, iommu, attr == DEV_DMA_COHERENT);
1383
1384         return 0;
1385 }
1386 EXPORT_SYMBOL_GPL(acpi_dma_configure);
1387
1388 /**
1389  * acpi_dma_deconfigure - Tear-down DMA configuration for the device.
1390  * @dev: The pointer to the device
1391  */
1392 void acpi_dma_deconfigure(struct device *dev)
1393 {
1394         arch_teardown_dma_ops(dev);
1395 }
1396 EXPORT_SYMBOL_GPL(acpi_dma_deconfigure);
1397
1398 static void acpi_init_coherency(struct acpi_device *adev)
1399 {
1400         unsigned long long cca = 0;
1401         acpi_status status;
1402         struct acpi_device *parent = adev->parent;
1403
1404         if (parent && parent->flags.cca_seen) {
1405                 /*
1406                  * From ACPI spec, OSPM will ignore _CCA if an ancestor
1407                  * already saw one.
1408                  */
1409                 adev->flags.cca_seen = 1;
1410                 cca = parent->flags.coherent_dma;
1411         } else {
1412                 status = acpi_evaluate_integer(adev->handle, "_CCA",
1413                                                NULL, &cca);
1414                 if (ACPI_SUCCESS(status))
1415                         adev->flags.cca_seen = 1;
1416                 else if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1417                         /*
1418                          * If architecture does not specify that _CCA is
1419                          * required for DMA-able devices (e.g. x86),
1420                          * we default to _CCA=1.
1421                          */
1422                         cca = 1;
1423                 else
1424                         acpi_handle_debug(adev->handle,
1425                                           "ACPI device is missing _CCA.\n");
1426         }
1427
1428         adev->flags.coherent_dma = cca;
1429 }
1430
1431 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1432                              int type, unsigned long long sta)
1433 {
1434         INIT_LIST_HEAD(&device->pnp.ids);
1435         device->device_type = type;
1436         device->handle = handle;
1437         device->parent = acpi_bus_get_parent(handle);
1438         device->fwnode.type = FWNODE_ACPI;
1439         acpi_set_device_status(device, sta);
1440         acpi_device_get_busid(device);
1441         acpi_set_pnp_ids(handle, &device->pnp, type);
1442         acpi_init_properties(device);
1443         acpi_bus_get_flags(device);
1444         device->flags.match_driver = false;
1445         device->flags.initialized = true;
1446         acpi_device_clear_enumerated(device);
1447         device_initialize(&device->dev);
1448         dev_set_uevent_suppress(&device->dev, true);
1449         acpi_init_coherency(device);
1450 }
1451
1452 void acpi_device_add_finalize(struct acpi_device *device)
1453 {
1454         dev_set_uevent_suppress(&device->dev, false);
1455         kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1456 }
1457
1458 static int acpi_add_single_object(struct acpi_device **child,
1459                                   acpi_handle handle, int type,
1460                                   unsigned long long sta)
1461 {
1462         int result;
1463         struct acpi_device *device;
1464         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1465
1466         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1467         if (!device) {
1468                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1469                 return -ENOMEM;
1470         }
1471
1472         acpi_init_device_object(device, handle, type, sta);
1473         acpi_bus_get_power_flags(device);
1474         acpi_bus_get_wakeup_device_flags(device);
1475
1476         result = acpi_device_add(device, acpi_device_release);
1477         if (result) {
1478                 acpi_device_release(&device->dev);
1479                 return result;
1480         }
1481
1482         acpi_power_add_remove_device(device, true);
1483         acpi_device_add_finalize(device);
1484         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1485         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1486                 dev_name(&device->dev), (char *) buffer.pointer,
1487                 device->parent ? dev_name(&device->parent->dev) : "(null)"));
1488         kfree(buffer.pointer);
1489         *child = device;
1490         return 0;
1491 }
1492
1493 static acpi_status acpi_get_resource_memory(struct acpi_resource *ares,
1494                                             void *context)
1495 {
1496         struct resource *res = context;
1497
1498         if (acpi_dev_resource_memory(ares, res))
1499                 return AE_CTRL_TERMINATE;
1500
1501         return AE_OK;
1502 }
1503
1504 static bool acpi_device_should_be_hidden(acpi_handle handle)
1505 {
1506         acpi_status status;
1507         struct resource res;
1508
1509         /* Check if it should ignore the UART device */
1510         if (!(spcr_uart_addr && acpi_has_method(handle, METHOD_NAME__CRS)))
1511                 return false;
1512
1513         /*
1514          * The UART device described in SPCR table is assumed to have only one
1515          * memory resource present. So we only look for the first one here.
1516          */
1517         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1518                                      acpi_get_resource_memory, &res);
1519         if (ACPI_FAILURE(status) || res.start != spcr_uart_addr)
1520                 return false;
1521
1522         acpi_handle_info(handle, "The UART device @%pa in SPCR table will be hidden\n",
1523                          &res.start);
1524
1525         return true;
1526 }
1527
1528 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1529                                     unsigned long long *sta)
1530 {
1531         acpi_status status;
1532         acpi_object_type acpi_type;
1533
1534         status = acpi_get_type(handle, &acpi_type);
1535         if (ACPI_FAILURE(status))
1536                 return -ENODEV;
1537
1538         switch (acpi_type) {
1539         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1540         case ACPI_TYPE_DEVICE:
1541                 if (acpi_device_should_be_hidden(handle))
1542                         return -ENODEV;
1543
1544                 *type = ACPI_BUS_TYPE_DEVICE;
1545                 status = acpi_bus_get_status_handle(handle, sta);
1546                 if (ACPI_FAILURE(status))
1547                         *sta = 0;
1548                 break;
1549         case ACPI_TYPE_PROCESSOR:
1550                 *type = ACPI_BUS_TYPE_PROCESSOR;
1551                 status = acpi_bus_get_status_handle(handle, sta);
1552                 if (ACPI_FAILURE(status))
1553                         return -ENODEV;
1554                 break;
1555         case ACPI_TYPE_THERMAL:
1556                 *type = ACPI_BUS_TYPE_THERMAL;
1557                 *sta = ACPI_STA_DEFAULT;
1558                 break;
1559         case ACPI_TYPE_POWER:
1560                 *type = ACPI_BUS_TYPE_POWER;
1561                 *sta = ACPI_STA_DEFAULT;
1562                 break;
1563         default:
1564                 return -ENODEV;
1565         }
1566
1567         return 0;
1568 }
1569
1570 bool acpi_device_is_present(struct acpi_device *adev)
1571 {
1572         if (adev->status.present || adev->status.functional)
1573                 return true;
1574
1575         adev->flags.initialized = false;
1576         return false;
1577 }
1578
1579 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1580                                        const char *idstr,
1581                                        const struct acpi_device_id **matchid)
1582 {
1583         const struct acpi_device_id *devid;
1584
1585         if (handler->match)
1586                 return handler->match(idstr, matchid);
1587
1588         for (devid = handler->ids; devid->id[0]; devid++)
1589                 if (!strcmp((char *)devid->id, idstr)) {
1590                         if (matchid)
1591                                 *matchid = devid;
1592
1593                         return true;
1594                 }
1595
1596         return false;
1597 }
1598
1599 static struct acpi_scan_handler *acpi_scan_match_handler(const char *idstr,
1600                                         const struct acpi_device_id **matchid)
1601 {
1602         struct acpi_scan_handler *handler;
1603
1604         list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1605                 if (acpi_scan_handler_matching(handler, idstr, matchid))
1606                         return handler;
1607
1608         return NULL;
1609 }
1610
1611 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1612 {
1613         if (!!hotplug->enabled == !!val)
1614                 return;
1615
1616         mutex_lock(&acpi_scan_lock);
1617
1618         hotplug->enabled = val;
1619
1620         mutex_unlock(&acpi_scan_lock);
1621 }
1622
1623 static void acpi_scan_init_hotplug(struct acpi_device *adev)
1624 {
1625         struct acpi_hardware_id *hwid;
1626
1627         if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
1628                 acpi_dock_add(adev);
1629                 return;
1630         }
1631         list_for_each_entry(hwid, &adev->pnp.ids, list) {
1632                 struct acpi_scan_handler *handler;
1633
1634                 handler = acpi_scan_match_handler(hwid->id, NULL);
1635                 if (handler) {
1636                         adev->flags.hotplug_notify = true;
1637                         break;
1638                 }
1639         }
1640 }
1641
1642 static void acpi_device_dep_initialize(struct acpi_device *adev)
1643 {
1644         struct acpi_dep_data *dep;
1645         struct acpi_handle_list dep_devices;
1646         acpi_status status;
1647         int i;
1648
1649         if (!acpi_has_method(adev->handle, "_DEP"))
1650                 return;
1651
1652         status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
1653                                         &dep_devices);
1654         if (ACPI_FAILURE(status)) {
1655                 dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
1656                 return;
1657         }
1658
1659         for (i = 0; i < dep_devices.count; i++) {
1660                 struct acpi_device_info *info;
1661                 int skip;
1662
1663                 status = acpi_get_object_info(dep_devices.handles[i], &info);
1664                 if (ACPI_FAILURE(status)) {
1665                         dev_dbg(&adev->dev, "Error reading _DEP device info\n");
1666                         continue;
1667                 }
1668
1669                 /*
1670                  * Skip the dependency of Windows System Power
1671                  * Management Controller
1672                  */
1673                 skip = info->valid & ACPI_VALID_HID &&
1674                         !strcmp(info->hardware_id.string, "INT3396");
1675
1676                 kfree(info);
1677
1678                 if (skip)
1679                         continue;
1680
1681                 dep = kzalloc(sizeof(struct acpi_dep_data), GFP_KERNEL);
1682                 if (!dep)
1683                         return;
1684
1685                 dep->master = dep_devices.handles[i];
1686                 dep->slave  = adev->handle;
1687                 adev->dep_unmet++;
1688
1689                 mutex_lock(&acpi_dep_list_lock);
1690                 list_add_tail(&dep->node , &acpi_dep_list);
1691                 mutex_unlock(&acpi_dep_list_lock);
1692         }
1693 }
1694
1695 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
1696                                       void *not_used, void **return_value)
1697 {
1698         struct acpi_device *device = NULL;
1699         int type;
1700         unsigned long long sta;
1701         int result;
1702
1703         acpi_bus_get_device(handle, &device);
1704         if (device)
1705                 goto out;
1706
1707         result = acpi_bus_type_and_status(handle, &type, &sta);
1708         if (result)
1709                 return AE_OK;
1710
1711         if (type == ACPI_BUS_TYPE_POWER) {
1712                 acpi_add_power_resource(handle);
1713                 return AE_OK;
1714         }
1715
1716         acpi_add_single_object(&device, handle, type, sta);
1717         if (!device)
1718                 return AE_CTRL_DEPTH;
1719
1720         acpi_scan_init_hotplug(device);
1721         acpi_device_dep_initialize(device);
1722
1723  out:
1724         if (!*return_value)
1725                 *return_value = device;
1726
1727         return AE_OK;
1728 }
1729
1730 static int acpi_check_spi_i2c_slave(struct acpi_resource *ares, void *data)
1731 {
1732         bool *is_spi_i2c_slave_p = data;
1733
1734         if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
1735                 return 1;
1736
1737         /*
1738          * devices that are connected to UART still need to be enumerated to
1739          * platform bus
1740          */
1741         if (ares->data.common_serial_bus.type != ACPI_RESOURCE_SERIAL_TYPE_UART)
1742                 *is_spi_i2c_slave_p = true;
1743
1744          /* no need to do more checking */
1745         return -1;
1746 }
1747
1748 static void acpi_default_enumeration(struct acpi_device *device)
1749 {
1750         struct list_head resource_list;
1751         bool is_spi_i2c_slave = false;
1752
1753         /*
1754          * Do not enumerate SPI/I2C slaves as they will be enumerated by their
1755          * respective parents.
1756          */
1757         INIT_LIST_HEAD(&resource_list);
1758         acpi_dev_get_resources(device, &resource_list, acpi_check_spi_i2c_slave,
1759                                &is_spi_i2c_slave);
1760         acpi_dev_free_resource_list(&resource_list);
1761         if (!is_spi_i2c_slave) {
1762                 acpi_create_platform_device(device, NULL);
1763                 acpi_device_set_enumerated(device);
1764         } else {
1765                 blocking_notifier_call_chain(&acpi_reconfig_chain,
1766                                              ACPI_RECONFIG_DEVICE_ADD, device);
1767         }
1768 }
1769
1770 static const struct acpi_device_id generic_device_ids[] = {
1771         {ACPI_DT_NAMESPACE_HID, },
1772         {"", },
1773 };
1774
1775 static int acpi_generic_device_attach(struct acpi_device *adev,
1776                                       const struct acpi_device_id *not_used)
1777 {
1778         /*
1779          * Since ACPI_DT_NAMESPACE_HID is the only ID handled here, the test
1780          * below can be unconditional.
1781          */
1782         if (adev->data.of_compatible)
1783                 acpi_default_enumeration(adev);
1784
1785         return 1;
1786 }
1787
1788 static struct acpi_scan_handler generic_device_handler = {
1789         .ids = generic_device_ids,
1790         .attach = acpi_generic_device_attach,
1791 };
1792
1793 static int acpi_scan_attach_handler(struct acpi_device *device)
1794 {
1795         struct acpi_hardware_id *hwid;
1796         int ret = 0;
1797
1798         list_for_each_entry(hwid, &device->pnp.ids, list) {
1799                 const struct acpi_device_id *devid;
1800                 struct acpi_scan_handler *handler;
1801
1802                 handler = acpi_scan_match_handler(hwid->id, &devid);
1803                 if (handler) {
1804                         if (!handler->attach) {
1805                                 device->pnp.type.platform_id = 0;
1806                                 continue;
1807                         }
1808                         device->handler = handler;
1809                         ret = handler->attach(device, devid);
1810                         if (ret > 0)
1811                                 break;
1812
1813                         device->handler = NULL;
1814                         if (ret < 0)
1815                                 break;
1816                 }
1817         }
1818
1819         return ret;
1820 }
1821
1822 static void acpi_bus_attach(struct acpi_device *device)
1823 {
1824         struct acpi_device *child;
1825         acpi_handle ejd;
1826         int ret;
1827
1828         if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
1829                 register_dock_dependent_device(device, ejd);
1830
1831         acpi_bus_get_status(device);
1832         /* Skip devices that are not present. */
1833         if (!acpi_device_is_present(device)) {
1834                 acpi_device_clear_enumerated(device);
1835                 device->flags.power_manageable = 0;
1836                 return;
1837         }
1838         if (device->handler)
1839                 goto ok;
1840
1841         if (!device->flags.initialized) {
1842                 device->flags.power_manageable =
1843                         device->power.states[ACPI_STATE_D0].flags.valid;
1844                 if (acpi_bus_init_power(device))
1845                         device->flags.power_manageable = 0;
1846
1847                 device->flags.initialized = true;
1848         } else if (device->flags.visited) {
1849                 goto ok;
1850         }
1851
1852         ret = acpi_scan_attach_handler(device);
1853         if (ret < 0)
1854                 return;
1855
1856         device->flags.match_driver = true;
1857         if (ret > 0) {
1858                 acpi_device_set_enumerated(device);
1859                 goto ok;
1860         }
1861
1862         ret = device_attach(&device->dev);
1863         if (ret < 0)
1864                 return;
1865
1866         if (device->pnp.type.platform_id)
1867                 acpi_default_enumeration(device);
1868         else
1869                 acpi_device_set_enumerated(device);
1870
1871  ok:
1872         list_for_each_entry(child, &device->children, node)
1873                 acpi_bus_attach(child);
1874
1875         if (device->handler && device->handler->hotplug.notify_online)
1876                 device->handler->hotplug.notify_online(device);
1877 }
1878
1879 void acpi_walk_dep_device_list(acpi_handle handle)
1880 {
1881         struct acpi_dep_data *dep, *tmp;
1882         struct acpi_device *adev;
1883
1884         mutex_lock(&acpi_dep_list_lock);
1885         list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
1886                 if (dep->master == handle) {
1887                         acpi_bus_get_device(dep->slave, &adev);
1888                         if (!adev)
1889                                 continue;
1890
1891                         adev->dep_unmet--;
1892                         if (!adev->dep_unmet)
1893                                 acpi_bus_attach(adev);
1894                         list_del(&dep->node);
1895                         kfree(dep);
1896                 }
1897         }
1898         mutex_unlock(&acpi_dep_list_lock);
1899 }
1900 EXPORT_SYMBOL_GPL(acpi_walk_dep_device_list);
1901
1902 /**
1903  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
1904  * @handle: Root of the namespace scope to scan.
1905  *
1906  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
1907  * found devices.
1908  *
1909  * If no devices were found, -ENODEV is returned, but it does not mean that
1910  * there has been a real error.  There just have been no suitable ACPI objects
1911  * in the table trunk from which the kernel could create a device and add an
1912  * appropriate driver.
1913  *
1914  * Must be called under acpi_scan_lock.
1915  */
1916 int acpi_bus_scan(acpi_handle handle)
1917 {
1918         void *device = NULL;
1919
1920         if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
1921                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1922                                     acpi_bus_check_add, NULL, NULL, &device);
1923
1924         if (device) {
1925                 acpi_bus_attach(device);
1926                 return 0;
1927         }
1928         return -ENODEV;
1929 }
1930 EXPORT_SYMBOL(acpi_bus_scan);
1931
1932 /**
1933  * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
1934  * @adev: Root of the ACPI namespace scope to walk.
1935  *
1936  * Must be called under acpi_scan_lock.
1937  */
1938 void acpi_bus_trim(struct acpi_device *adev)
1939 {
1940         struct acpi_scan_handler *handler = adev->handler;
1941         struct acpi_device *child;
1942
1943         list_for_each_entry_reverse(child, &adev->children, node)
1944                 acpi_bus_trim(child);
1945
1946         adev->flags.match_driver = false;
1947         if (handler) {
1948                 if (handler->detach)
1949                         handler->detach(adev);
1950
1951                 adev->handler = NULL;
1952         } else {
1953                 device_release_driver(&adev->dev);
1954         }
1955         /*
1956          * Most likely, the device is going away, so put it into D3cold before
1957          * that.
1958          */
1959         acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
1960         adev->flags.initialized = false;
1961         acpi_device_clear_enumerated(adev);
1962 }
1963 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1964
1965 static int acpi_bus_scan_fixed(void)
1966 {
1967         int result = 0;
1968
1969         /*
1970          * Enumerate all fixed-feature devices.
1971          */
1972         if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
1973                 struct acpi_device *device = NULL;
1974
1975                 result = acpi_add_single_object(&device, NULL,
1976                                                 ACPI_BUS_TYPE_POWER_BUTTON,
1977                                                 ACPI_STA_DEFAULT);
1978                 if (result)
1979                         return result;
1980
1981                 device->flags.match_driver = true;
1982                 result = device_attach(&device->dev);
1983                 if (result < 0)
1984                         return result;
1985
1986                 device_init_wakeup(&device->dev, true);
1987         }
1988
1989         if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
1990                 struct acpi_device *device = NULL;
1991
1992                 result = acpi_add_single_object(&device, NULL,
1993                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
1994                                                 ACPI_STA_DEFAULT);
1995                 if (result)
1996                         return result;
1997
1998                 device->flags.match_driver = true;
1999                 result = device_attach(&device->dev);
2000         }
2001
2002         return result < 0 ? result : 0;
2003 }
2004
2005 static void __init acpi_get_spcr_uart_addr(void)
2006 {
2007         acpi_status status;
2008         struct acpi_table_spcr *spcr_ptr;
2009
2010         status = acpi_get_table(ACPI_SIG_SPCR, 0,
2011                                 (struct acpi_table_header **)&spcr_ptr);
2012         if (ACPI_SUCCESS(status))
2013                 spcr_uart_addr = spcr_ptr->serial_port.address;
2014         else
2015                 printk(KERN_WARNING PREFIX "STAO table present, but SPCR is missing\n");
2016 }
2017
2018 static bool acpi_scan_initialized;
2019
2020 int __init acpi_scan_init(void)
2021 {
2022         int result;
2023         acpi_status status;
2024         struct acpi_table_stao *stao_ptr;
2025
2026         acpi_pci_root_init();
2027         acpi_pci_link_init();
2028         acpi_processor_init();
2029         acpi_lpss_init();
2030         acpi_apd_init();
2031         acpi_cmos_rtc_init();
2032         acpi_container_init();
2033         acpi_memory_hotplug_init();
2034         acpi_pnp_init();
2035         acpi_int340x_thermal_init();
2036         acpi_amba_init();
2037         acpi_watchdog_init();
2038
2039         acpi_scan_add_handler(&generic_device_handler);
2040
2041         /*
2042          * If there is STAO table, check whether it needs to ignore the UART
2043          * device in SPCR table.
2044          */
2045         status = acpi_get_table(ACPI_SIG_STAO, 0,
2046                                 (struct acpi_table_header **)&stao_ptr);
2047         if (ACPI_SUCCESS(status)) {
2048                 if (stao_ptr->header.length > sizeof(struct acpi_table_stao))
2049                         printk(KERN_INFO PREFIX "STAO Name List not yet supported.");
2050
2051                 if (stao_ptr->ignore_uart)
2052                         acpi_get_spcr_uart_addr();
2053         }
2054
2055         mutex_lock(&acpi_scan_lock);
2056         /*
2057          * Enumerate devices in the ACPI namespace.
2058          */
2059         result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2060         if (result)
2061                 goto out;
2062
2063         result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2064         if (result)
2065                 goto out;
2066
2067         /* Fixed feature devices do not exist on HW-reduced platform */
2068         if (!acpi_gbl_reduced_hardware) {
2069                 result = acpi_bus_scan_fixed();
2070                 if (result) {
2071                         acpi_detach_data(acpi_root->handle,
2072                                          acpi_scan_drop_device);
2073                         acpi_device_del(acpi_root);
2074                         put_device(&acpi_root->dev);
2075                         goto out;
2076                 }
2077         }
2078
2079         acpi_gpe_apply_masked_gpes();
2080         acpi_update_all_gpes();
2081         acpi_ec_ecdt_start();
2082
2083         acpi_scan_initialized = true;
2084
2085  out:
2086         mutex_unlock(&acpi_scan_lock);
2087         return result;
2088 }
2089
2090 static struct acpi_probe_entry *ape;
2091 static int acpi_probe_count;
2092 static DEFINE_MUTEX(acpi_probe_mutex);
2093
2094 static int __init acpi_match_madt(struct acpi_subtable_header *header,
2095                                   const unsigned long end)
2096 {
2097         if (!ape->subtable_valid || ape->subtable_valid(header, ape))
2098                 if (!ape->probe_subtbl(header, end))
2099                         acpi_probe_count++;
2100
2101         return 0;
2102 }
2103
2104 int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr)
2105 {
2106         int count = 0;
2107
2108         if (acpi_disabled)
2109                 return 0;
2110
2111         mutex_lock(&acpi_probe_mutex);
2112         for (ape = ap_head; nr; ape++, nr--) {
2113                 if (ACPI_COMPARE_NAME(ACPI_SIG_MADT, ape->id)) {
2114                         acpi_probe_count = 0;
2115                         acpi_table_parse_madt(ape->type, acpi_match_madt, 0);
2116                         count += acpi_probe_count;
2117                 } else {
2118                         int res;
2119                         res = acpi_table_parse(ape->id, ape->probe_table);
2120                         if (!res)
2121                                 count++;
2122                 }
2123         }
2124         mutex_unlock(&acpi_probe_mutex);
2125
2126         return count;
2127 }
2128
2129 struct acpi_table_events_work {
2130         struct work_struct work;
2131         void *table;
2132         u32 event;
2133 };
2134
2135 static void acpi_table_events_fn(struct work_struct *work)
2136 {
2137         struct acpi_table_events_work *tew;
2138
2139         tew = container_of(work, struct acpi_table_events_work, work);
2140
2141         if (tew->event == ACPI_TABLE_EVENT_LOAD) {
2142                 acpi_scan_lock_acquire();
2143                 acpi_bus_scan(ACPI_ROOT_OBJECT);
2144                 acpi_scan_lock_release();
2145         }
2146
2147         kfree(tew);
2148 }
2149
2150 void acpi_scan_table_handler(u32 event, void *table, void *context)
2151 {
2152         struct acpi_table_events_work *tew;
2153
2154         if (!acpi_scan_initialized)
2155                 return;
2156
2157         if (event != ACPI_TABLE_EVENT_LOAD)
2158                 return;
2159
2160         tew = kmalloc(sizeof(*tew), GFP_KERNEL);
2161         if (!tew)
2162                 return;
2163
2164         INIT_WORK(&tew->work, acpi_table_events_fn);
2165         tew->table = table;
2166         tew->event = event;
2167
2168         schedule_work(&tew->work);
2169 }
2170
2171 int acpi_reconfig_notifier_register(struct notifier_block *nb)
2172 {
2173         return blocking_notifier_chain_register(&acpi_reconfig_chain, nb);
2174 }
2175 EXPORT_SYMBOL(acpi_reconfig_notifier_register);
2176
2177 int acpi_reconfig_notifier_unregister(struct notifier_block *nb)
2178 {
2179         return blocking_notifier_chain_unregister(&acpi_reconfig_chain, nb);
2180 }
2181 EXPORT_SYMBOL(acpi_reconfig_notifier_unregister);