drivers/acpi/scan.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * scan.c - support for transforming the ACPI namespace into individual objects
   4  */
   5
   6 #define pr_fmt(fmt) "ACPI: " fmt
   7
   8 #include <linux/module.h>
   9 #include <linux/init.h>
  10 #include <linux/slab.h>
  11 #include <linux/kernel.h>
  12 #include <linux/acpi.h>
  13 #include <linux/acpi_iort.h>
  14 #include <linux/acpi_viot.h>
  15 #include <linux/iommu.h>
  16 #include <linux/signal.h>
  17 #include <linux/kthread.h>
  18 #include <linux/dmi.h>
  19 #include <linux/dma-map-ops.h>
  20 #include <linux/platform_data/x86/apple.h>
  21 #include <linux/pgtable.h>
  22 #include <linux/crc32.h>
  23 #include <linux/dma-direct.h>
  24
  25 #include "internal.h"
  26 #include "sleep.h"
  27
  28 #define ACPI_BUS_CLASS                  "system_bus"
  29 #define ACPI_BUS_HID                    "LNXSYBUS"
  30 #define ACPI_BUS_DEVICE_NAME            "System Bus"
  31
  32 #define INVALID_ACPI_HANDLE     ((acpi_handle)ZERO_PAGE(0))
  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 void acpi_scan_lock_acquire(void)
  53 {
  54         mutex_lock(&acpi_scan_lock);
  55 }
  56 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
  57
  58 void acpi_scan_lock_release(void)
  59 {
  60         mutex_unlock(&acpi_scan_lock);
  61 }
  62 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
  63
  64 void acpi_lock_hp_context(void)
  65 {
  66         mutex_lock(&acpi_hp_context_lock);
  67 }
  68
  69 void acpi_unlock_hp_context(void)
  70 {
  71         mutex_unlock(&acpi_hp_context_lock);
  72 }
  73
  74 void acpi_initialize_hp_context(struct acpi_device *adev,
  75                                 struct acpi_hotplug_context *hp,
  76                                 acpi_hp_notify notify, acpi_hp_uevent uevent)
  77 {
  78         acpi_lock_hp_context();
  79         hp->notify = notify;
  80         hp->uevent = uevent;
  81         acpi_set_hp_context(adev, hp);
  82         acpi_unlock_hp_context();
  83 }
  84 EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
  85
  86 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
  87 {
  88         if (!handler)
  89                 return -EINVAL;
  90
  91         list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
  92         return 0;
  93 }
  94
  95 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
  96                                        const char *hotplug_profile_name)
  97 {
  98         int error;
  99
 100         error = acpi_scan_add_handler(handler);
 101         if (error)
 102                 return error;
 103
 104         acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
 105         return 0;
 106 }
 107
 108 bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
 109 {
 110         struct acpi_device_physical_node *pn;
 111         bool offline = true;
 112         char *envp[] = { "EVENT=offline", NULL };
 113
 114         /*
 115          * acpi_container_offline() calls this for all of the container's
 116          * children under the container's physical_node_lock lock.
 117          */
 118         mutex_lock_nested(&adev->physical_node_lock, SINGLE_DEPTH_NESTING);
 119
 120         list_for_each_entry(pn, &adev->physical_node_list, node)
 121                 if (device_supports_offline(pn->dev) && !pn->dev->offline) {
 122                         if (uevent)
 123                                 kobject_uevent_env(&pn->dev->kobj, KOBJ_CHANGE, envp);
 124
 125                         offline = false;
 126                         break;
 127                 }
 128
 129         mutex_unlock(&adev->physical_node_lock);
 130         return offline;
 131 }
 132
 133 static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
 134                                     void **ret_p)
 135 {
 136         struct acpi_device *device = acpi_fetch_acpi_dev(handle);
 137         struct acpi_device_physical_node *pn;
 138         bool second_pass = (bool)data;
 139         acpi_status status = AE_OK;
 140
 141         if (!device)
 142                 return AE_OK;
 143
 144         if (device->handler && !device->handler->hotplug.enabled) {
 145                 *ret_p = &device->dev;
 146                 return AE_SUPPORT;
 147         }
 148
 149         mutex_lock(&device->physical_node_lock);
 150
 151         list_for_each_entry(pn, &device->physical_node_list, node) {
 152                 int ret;
 153
 154                 if (second_pass) {
 155                         /* Skip devices offlined by the first pass. */
 156                         if (pn->put_online)
 157                                 continue;
 158                 } else {
 159                         pn->put_online = false;
 160                 }
 161                 ret = device_offline(pn->dev);
 162                 if (ret >= 0) {
 163                         pn->put_online = !ret;
 164                 } else {
 165                         *ret_p = pn->dev;
 166                         if (second_pass) {
 167                                 status = AE_ERROR;
 168                                 break;
 169                         }
 170                 }
 171         }
 172
 173         mutex_unlock(&device->physical_node_lock);
 174
 175         return status;
 176 }
 177
 178 static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
 179                                    void **ret_p)
 180 {
 181         struct acpi_device *device = acpi_fetch_acpi_dev(handle);
 182         struct acpi_device_physical_node *pn;
 183
 184         if (!device)
 185                 return AE_OK;
 186
 187         mutex_lock(&device->physical_node_lock);
 188
 189         list_for_each_entry(pn, &device->physical_node_list, node)
 190                 if (pn->put_online) {
 191                         device_online(pn->dev);
 192                         pn->put_online = false;
 193                 }
 194
 195         mutex_unlock(&device->physical_node_lock);
 196
 197         return AE_OK;
 198 }
 199
 200 static int acpi_scan_try_to_offline(struct acpi_device *device)
 201 {
 202         acpi_handle handle = device->handle;
 203         struct device *errdev = NULL;
 204         acpi_status status;
 205
 206         /*
 207          * Carry out two passes here and ignore errors in the first pass,
 208          * because if the devices in question are memory blocks and
 209          * CONFIG_MEMCG is set, one of the blocks may hold data structures
 210          * that the other blocks depend on, but it is not known in advance which
 211          * block holds them.
 212          *
 213          * If the first pass is successful, the second one isn't needed, though.
 214          */
 215         status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 216                                      NULL, acpi_bus_offline, (void *)false,
 217                                      (void **)&errdev);
 218         if (status == AE_SUPPORT) {
 219                 dev_warn(errdev, "Offline disabled.\n");
 220                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 221                                     acpi_bus_online, NULL, NULL, NULL);
 222                 return -EPERM;
 223         }
 224         acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
 225         if (errdev) {
 226                 errdev = NULL;
 227                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
 228                                     NULL, acpi_bus_offline, (void *)true,
 229                                     (void **)&errdev);
 230                 if (!errdev)
 231                         acpi_bus_offline(handle, 0, (void *)true,
 232                                          (void **)&errdev);
 233
 234                 if (errdev) {
 235                         dev_warn(errdev, "Offline failed.\n");
 236                         acpi_bus_online(handle, 0, NULL, NULL);
 237                         acpi_walk_namespace(ACPI_TYPE_ANY, handle,
 238                                             ACPI_UINT32_MAX, acpi_bus_online,
 239                                             NULL, NULL, NULL);
 240                         return -EBUSY;
 241                 }
 242         }
 243         return 0;
 244 }
 245
 246 static int acpi_scan_check_and_detach(struct acpi_device *adev, void *check)
 247 {
 248         struct acpi_scan_handler *handler = adev->handler;
 249
 250         acpi_dev_for_each_child_reverse(adev, acpi_scan_check_and_detach, check);
 251
 252         if (check) {
 253                 acpi_bus_get_status(adev);
 254                 /*
 255                  * Skip devices that are still there and take the enabled
 256                  * flag into account.
 257                  */
 258                 if (acpi_device_is_enabled(adev))
 259                         return 0;
 260
 261                 /* Skip device that have not been enumerated. */
 262                 if (!acpi_device_enumerated(adev)) {
 263                         dev_dbg(&adev->dev, "Still not enumerated\n");
 264                         return 0;
 265                 }
 266         }
 267
 268         adev->flags.match_driver = false;
 269         if (handler) {
 270                 if (handler->detach)
 271                         handler->detach(adev);
 272
 273                 adev->handler = NULL;
 274         } else {
 275                 device_release_driver(&adev->dev);
 276         }
 277         /*
 278          * Most likely, the device is going away, so put it into D3cold before
 279          * that.
 280          */
 281         acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
 282         adev->flags.initialized = false;
 283         acpi_device_clear_enumerated(adev);
 284
 285         return 0;
 286 }
 287
 288 static void acpi_scan_check_subtree(struct acpi_device *adev)
 289 {
 290         acpi_scan_check_and_detach(adev, (void *)true);
 291 }
 292
 293 static int acpi_scan_hot_remove(struct acpi_device *device)
 294 {
 295         acpi_handle handle = device->handle;
 296         unsigned long long sta;
 297         acpi_status status;
 298
 299         if (device->handler && device->handler->hotplug.demand_offline) {
 300                 if (!acpi_scan_is_offline(device, true))
 301                         return -EBUSY;
 302         } else {
 303                 int error = acpi_scan_try_to_offline(device);
 304                 if (error)
 305                         return error;
 306         }
 307
 308         acpi_handle_debug(handle, "Ejecting\n");
 309
 310         acpi_bus_trim(device);
 311
 312         acpi_evaluate_lck(handle, 0);
 313         /*
 314          * TBD: _EJD support.
 315          */
 316         status = acpi_evaluate_ej0(handle);
 317         if (status == AE_NOT_FOUND)
 318                 return -ENODEV;
 319         else if (ACPI_FAILURE(status))
 320                 return -EIO;
 321
 322         /*
 323          * Verify if eject was indeed successful.  If not, log an error
 324          * message.  No need to call _OST since _EJ0 call was made OK.
 325          */
 326         status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
 327         if (ACPI_FAILURE(status)) {
 328                 acpi_handle_warn(handle,
 329                         "Status check after eject failed (0x%x)\n", status);
 330         } else if (sta & ACPI_STA_DEVICE_ENABLED) {
 331                 acpi_handle_warn(handle,
 332                         "Eject incomplete - status 0x%llx\n", sta);
 333         }
 334
 335         return 0;
 336 }
 337
 338 static int acpi_scan_rescan_bus(struct acpi_device *adev)
 339 {
 340         struct acpi_scan_handler *handler = adev->handler;
 341         int ret;
 342
 343         if (handler && handler->hotplug.scan_dependent)
 344                 ret = handler->hotplug.scan_dependent(adev);
 345         else
 346                 ret = acpi_bus_scan(adev->handle);
 347
 348         if (ret)
 349                 dev_info(&adev->dev, "Namespace scan failure\n");
 350
 351         return ret;
 352 }
 353
 354 static int acpi_scan_device_check(struct acpi_device *adev)
 355 {
 356         struct acpi_device *parent;
 357
 358         acpi_scan_check_subtree(adev);
 359
 360         if (!acpi_device_is_present(adev))
 361                 return 0;
 362
 363         /*
 364          * This function is only called for device objects for which matching
 365          * scan handlers exist.  The only situation in which the scan handler
 366          * is not attached to this device object yet is when the device has
 367          * just appeared (either it wasn't present at all before or it was
 368          * removed and then added again).
 369          */
 370         if (adev->handler) {
 371                 dev_dbg(&adev->dev, "Already enumerated\n");
 372                 return 0;
 373         }
 374
 375         parent = acpi_dev_parent(adev);
 376         if (!parent)
 377                 parent = adev;
 378
 379         return acpi_scan_rescan_bus(parent);
 380 }
 381
 382 static int acpi_scan_bus_check(struct acpi_device *adev)
 383 {
 384         acpi_scan_check_subtree(adev);
 385
 386         return acpi_scan_rescan_bus(adev);
 387 }
 388
 389 static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type)
 390 {
 391         switch (type) {
 392         case ACPI_NOTIFY_BUS_CHECK:
 393                 return acpi_scan_bus_check(adev);
 394         case ACPI_NOTIFY_DEVICE_CHECK:
 395                 return acpi_scan_device_check(adev);
 396         case ACPI_NOTIFY_EJECT_REQUEST:
 397         case ACPI_OST_EC_OSPM_EJECT:
 398                 if (adev->handler && !adev->handler->hotplug.enabled) {
 399                         dev_info(&adev->dev, "Eject disabled\n");
 400                         return -EPERM;
 401                 }
 402                 acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST,
 403                                   ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
 404                 return acpi_scan_hot_remove(adev);
 405         }
 406         return -EINVAL;
 407 }
 408
 409 void acpi_device_hotplug(struct acpi_device *adev, u32 src)
 410 {
 411         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
 412         int error = -ENODEV;
 413
 414         lock_device_hotplug();
 415         mutex_lock(&acpi_scan_lock);
 416
 417         /*
 418          * The device object's ACPI handle cannot become invalid as long as we
 419          * are holding acpi_scan_lock, but it might have become invalid before
 420          * that lock was acquired.
 421          */
 422         if (adev->handle == INVALID_ACPI_HANDLE)
 423                 goto err_out;
 424
 425         if (adev->flags.is_dock_station) {
 426                 error = dock_notify(adev, src);
 427         } else if (adev->flags.hotplug_notify) {
 428                 error = acpi_generic_hotplug_event(adev, src);
 429         } else {
 430                 acpi_hp_notify notify;
 431
 432                 acpi_lock_hp_context();
 433                 notify = adev->hp ? adev->hp->notify : NULL;
 434                 acpi_unlock_hp_context();
 435                 /*
 436                  * There may be additional notify handlers for device objects
 437                  * without the .event() callback, so ignore them here.
 438                  */
 439                 if (notify)
 440                         error = notify(adev, src);
 441                 else
 442                         goto out;
 443         }
 444         switch (error) {
 445         case 0:
 446                 ost_code = ACPI_OST_SC_SUCCESS;
 447                 break;
 448         case -EPERM:
 449                 ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
 450                 break;
 451         case -EBUSY:
 452                 ost_code = ACPI_OST_SC_DEVICE_BUSY;
 453                 break;
 454         default:
 455                 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
 456                 break;
 457         }
 458
 459  err_out:
 460         acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
 461
 462  out:
 463         acpi_put_acpi_dev(adev);
 464         mutex_unlock(&acpi_scan_lock);
 465         unlock_device_hotplug();
 466 }
 467
 468 static void acpi_free_power_resources_lists(struct acpi_device *device)
 469 {
 470         int i;
 471
 472         if (device->wakeup.flags.valid)
 473                 acpi_power_resources_list_free(&device->wakeup.resources);
 474
 475         if (!device->power.flags.power_resources)
 476                 return;
 477
 478         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
 479                 struct acpi_device_power_state *ps = &device->power.states[i];
 480                 acpi_power_resources_list_free(&ps->resources);
 481         }
 482 }
 483
 484 static void acpi_device_release(struct device *dev)
 485 {
 486         struct acpi_device *acpi_dev = to_acpi_device(dev);
 487
 488         acpi_free_properties(acpi_dev);
 489         acpi_free_pnp_ids(&acpi_dev->pnp);
 490         acpi_free_power_resources_lists(acpi_dev);
 491         kfree(acpi_dev);
 492 }
 493
 494 static void acpi_device_del(struct acpi_device *device)
 495 {
 496         struct acpi_device_bus_id *acpi_device_bus_id;
 497
 498         mutex_lock(&acpi_device_lock);
 499
 500         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node)
 501                 if (!strcmp(acpi_device_bus_id->bus_id,
 502                             acpi_device_hid(device))) {
 503                         ida_free(&acpi_device_bus_id->instance_ida,
 504                                  device->pnp.instance_no);
 505                         if (ida_is_empty(&acpi_device_bus_id->instance_ida)) {
 506                                 list_del(&acpi_device_bus_id->node);
 507                                 kfree_const(acpi_device_bus_id->bus_id);
 508                                 kfree(acpi_device_bus_id);
 509                         }
 510                         break;
 511                 }
 512
 513         list_del(&device->wakeup_list);
 514
 515         mutex_unlock(&acpi_device_lock);
 516
 517         acpi_power_add_remove_device(device, false);
 518         acpi_device_remove_files(device);
 519         if (device->remove)
 520                 device->remove(device);
 521
 522         device_del(&device->dev);
 523 }
 524
 525 static BLOCKING_NOTIFIER_HEAD(acpi_reconfig_chain);
 526
 527 static LIST_HEAD(acpi_device_del_list);
 528 static DEFINE_MUTEX(acpi_device_del_lock);
 529
 530 static void acpi_device_del_work_fn(struct work_struct *work_not_used)
 531 {
 532         for (;;) {
 533                 struct acpi_device *adev;
 534
 535                 mutex_lock(&acpi_device_del_lock);
 536
 537                 if (list_empty(&acpi_device_del_list)) {
 538                         mutex_unlock(&acpi_device_del_lock);
 539                         break;
 540                 }
 541                 adev = list_first_entry(&acpi_device_del_list,
 542                                         struct acpi_device, del_list);
 543                 list_del(&adev->del_list);
 544
 545                 mutex_unlock(&acpi_device_del_lock);
 546
 547                 blocking_notifier_call_chain(&acpi_reconfig_chain,
 548                                              ACPI_RECONFIG_DEVICE_REMOVE, adev);
 549
 550                 acpi_device_del(adev);
 551                 /*
 552                  * Drop references to all power resources that might have been
 553                  * used by the device.
 554                  */
 555                 acpi_power_transition(adev, ACPI_STATE_D3_COLD);
 556                 acpi_dev_put(adev);
 557         }
 558 }
 559
 560 /**
 561  * acpi_scan_drop_device - Drop an ACPI device object.
 562  * @handle: Handle of an ACPI namespace node, not used.
 563  * @context: Address of the ACPI device object to drop.
 564  *
 565  * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
 566  * namespace node the device object pointed to by @context is attached to.
 567  *
 568  * The unregistration is carried out asynchronously to avoid running
 569  * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
 570  * ensure the correct ordering (the device objects must be unregistered in the
 571  * same order in which the corresponding namespace nodes are deleted).
 572  */
 573 static void acpi_scan_drop_device(acpi_handle handle, void *context)
 574 {
 575         static DECLARE_WORK(work, acpi_device_del_work_fn);
 576         struct acpi_device *adev = context;
 577
 578         mutex_lock(&acpi_device_del_lock);
 579
 580         /*
 581          * Use the ACPI hotplug workqueue which is ordered, so this work item
 582          * won't run after any hotplug work items submitted subsequently.  That
 583          * prevents attempts to register device objects identical to those being
 584          * deleted from happening concurrently (such attempts result from
 585          * hotplug events handled via the ACPI hotplug workqueue).  It also will
 586          * run after all of the work items submitted previously, which helps
 587          * those work items to ensure that they are not accessing stale device
 588          * objects.
 589          */
 590         if (list_empty(&acpi_device_del_list))
 591                 acpi_queue_hotplug_work(&work);
 592
 593         list_add_tail(&adev->del_list, &acpi_device_del_list);
 594         /* Make acpi_ns_validate_handle() return NULL for this handle. */
 595         adev->handle = INVALID_ACPI_HANDLE;
 596
 597         mutex_unlock(&acpi_device_del_lock);
 598 }
 599
 600 static struct acpi_device *handle_to_device(acpi_handle handle,
 601                                             void (*callback)(void *))
 602 {
 603         struct acpi_device *adev = NULL;
 604         acpi_status status;
 605
 606         status = acpi_get_data_full(handle, acpi_scan_drop_device,
 607                                     (void **)&adev, callback);
 608         if (ACPI_FAILURE(status) || !adev) {
 609                 acpi_handle_debug(handle, "No context!\n");
 610                 return NULL;
 611         }
 612         return adev;
 613 }
 614
 615 /**
 616  * acpi_fetch_acpi_dev - Retrieve ACPI device object.
 617  * @handle: ACPI handle associated with the requested ACPI device object.
 618  *
 619  * Return a pointer to the ACPI device object associated with @handle, if
 620  * present, or NULL otherwise.
 621  */
 622 struct acpi_device *acpi_fetch_acpi_dev(acpi_handle handle)
 623 {
 624         return handle_to_device(handle, NULL);
 625 }
 626 EXPORT_SYMBOL_GPL(acpi_fetch_acpi_dev);
 627
 628 static void get_acpi_device(void *dev)
 629 {
 630         acpi_dev_get(dev);
 631 }
 632
 633 /**
 634  * acpi_get_acpi_dev - Retrieve ACPI device object and reference count it.
 635  * @handle: ACPI handle associated with the requested ACPI device object.
 636  *
 637  * Return a pointer to the ACPI device object associated with @handle and bump
 638  * up that object's reference counter (under the ACPI Namespace lock), if
 639  * present, or return NULL otherwise.
 640  *
 641  * The ACPI device object reference acquired by this function needs to be
 642  * dropped via acpi_dev_put().
 643  */
 644 struct acpi_device *acpi_get_acpi_dev(acpi_handle handle)
 645 {
 646         return handle_to_device(handle, get_acpi_device);
 647 }
 648 EXPORT_SYMBOL_GPL(acpi_get_acpi_dev);
 649
 650 static struct acpi_device_bus_id *acpi_device_bus_id_match(const char *dev_id)
 651 {
 652         struct acpi_device_bus_id *acpi_device_bus_id;
 653
 654         /* Find suitable bus_id and instance number in acpi_bus_id_list. */
 655         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
 656                 if (!strcmp(acpi_device_bus_id->bus_id, dev_id))
 657                         return acpi_device_bus_id;
 658         }
 659         return NULL;
 660 }
 661
 662 static int acpi_device_set_name(struct acpi_device *device,
 663                                 struct acpi_device_bus_id *acpi_device_bus_id)
 664 {
 665         struct ida *instance_ida = &acpi_device_bus_id->instance_ida;
 666         int result;
 667
 668         result = ida_alloc(instance_ida, GFP_KERNEL);
 669         if (result < 0)
 670                 return result;
 671
 672         device->pnp.instance_no = result;
 673         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, result);
 674         return 0;
 675 }
 676
 677 int acpi_tie_acpi_dev(struct acpi_device *adev)
 678 {
 679         acpi_handle handle = adev->handle;
 680         acpi_status status;
 681
 682         if (!handle)
 683                 return 0;
 684
 685         status = acpi_attach_data(handle, acpi_scan_drop_device, adev);
 686         if (ACPI_FAILURE(status)) {
 687                 acpi_handle_err(handle, "Unable to attach device data\n");
 688                 return -ENODEV;
 689         }
 690
 691         return 0;
 692 }
 693
 694 static void acpi_store_pld_crc(struct acpi_device *adev)
 695 {
 696         struct acpi_pld_info *pld;
 697         acpi_status status;
 698
 699         status = acpi_get_physical_device_location(adev->handle, &pld);
 700         if (ACPI_FAILURE(status))
 701                 return;
 702
 703         adev->pld_crc = crc32(~0, pld, sizeof(*pld));
 704         ACPI_FREE(pld);
 705 }
 706
 707 int acpi_device_add(struct acpi_device *device)
 708 {
 709         struct acpi_device_bus_id *acpi_device_bus_id;
 710         int result;
 711
 712         /*
 713          * Linkage
 714          * -------
 715          * Link this device to its parent and siblings.
 716          */
 717         INIT_LIST_HEAD(&device->wakeup_list);
 718         INIT_LIST_HEAD(&device->physical_node_list);
 719         INIT_LIST_HEAD(&device->del_list);
 720         mutex_init(&device->physical_node_lock);
 721
 722         mutex_lock(&acpi_device_lock);
 723
 724         acpi_device_bus_id = acpi_device_bus_id_match(acpi_device_hid(device));
 725         if (acpi_device_bus_id) {
 726                 result = acpi_device_set_name(device, acpi_device_bus_id);
 727                 if (result)
 728                         goto err_unlock;
 729         } else {
 730                 acpi_device_bus_id = kzalloc(sizeof(*acpi_device_bus_id),
 731                                              GFP_KERNEL);
 732                 if (!acpi_device_bus_id) {
 733                         result = -ENOMEM;
 734                         goto err_unlock;
 735                 }
 736                 acpi_device_bus_id->bus_id =
 737                         kstrdup_const(acpi_device_hid(device), GFP_KERNEL);
 738                 if (!acpi_device_bus_id->bus_id) {
 739                         kfree(acpi_device_bus_id);
 740                         result = -ENOMEM;
 741                         goto err_unlock;
 742                 }
 743
 744                 ida_init(&acpi_device_bus_id->instance_ida);
 745
 746                 result = acpi_device_set_name(device, acpi_device_bus_id);
 747                 if (result) {
 748                         kfree_const(acpi_device_bus_id->bus_id);
 749                         kfree(acpi_device_bus_id);
 750                         goto err_unlock;
 751                 }
 752
 753                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
 754         }
 755
 756         if (device->wakeup.flags.valid)
 757                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
 758
 759         acpi_store_pld_crc(device);
 760
 761         mutex_unlock(&acpi_device_lock);
 762
 763         result = device_add(&device->dev);
 764         if (result) {
 765                 dev_err(&device->dev, "Error registering device\n");
 766                 goto err;
 767         }
 768
 769         result = acpi_device_setup_files(device);
 770         if (result)
 771                 pr_err("Error creating sysfs interface for device %s\n",
 772                        dev_name(&device->dev));
 773
 774         return 0;
 775
 776 err:
 777         mutex_lock(&acpi_device_lock);
 778
 779         list_del(&device->wakeup_list);
 780
 781 err_unlock:
 782         mutex_unlock(&acpi_device_lock);
 783
 784         acpi_detach_data(device->handle, acpi_scan_drop_device);
 785
 786         return result;
 787 }
 788
 789 /* --------------------------------------------------------------------------
 790                                  Device Enumeration
 791    -------------------------------------------------------------------------- */
 792 static bool acpi_info_matches_ids(struct acpi_device_info *info,
 793                                   const char * const ids[])
 794 {
 795         struct acpi_pnp_device_id_list *cid_list = NULL;
 796         int i, index;
 797
 798         if (!(info->valid & ACPI_VALID_HID))
 799                 return false;
 800
 801         index = match_string(ids, -1, info->hardware_id.string);
 802         if (index >= 0)
 803                 return true;
 804
 805         if (info->valid & ACPI_VALID_CID)
 806                 cid_list = &info->compatible_id_list;
 807
 808         if (!cid_list)
 809                 return false;
 810
 811         for (i = 0; i < cid_list->count; i++) {
 812                 index = match_string(ids, -1, cid_list->ids[i].string);
 813                 if (index >= 0)
 814                         return true;
 815         }
 816
 817         return false;
 818 }
 819
 820 /* List of HIDs for which we ignore matching ACPI devices, when checking _DEP lists. */
 821 static const char * const acpi_ignore_dep_ids[] = {
 822         "PNP0D80", /* Windows-compatible System Power Management Controller */
 823         "INT33BD", /* Intel Baytrail Mailbox Device */
 824         "LATT2021", /* Lattice FW Update Client Driver */
 825         NULL
 826 };
 827
 828 /* List of HIDs for which we honor deps of matching ACPI devs, when checking _DEP lists. */
 829 static const char * const acpi_honor_dep_ids[] = {
 830         "INT3472", /* Camera sensor PMIC / clk and regulator info */
 831         "INTC1059", /* IVSC (TGL) driver must be loaded to allow i2c access to camera sensors */
 832         "INTC1095", /* IVSC (ADL) driver must be loaded to allow i2c access to camera sensors */
 833         "INTC100A", /* IVSC (RPL) driver must be loaded to allow i2c access to camera sensors */
 834         "INTC10CF", /* IVSC (MTL) driver must be loaded to allow i2c access to camera sensors */
 835         NULL
 836 };
 837
 838 static struct acpi_device *acpi_find_parent_acpi_dev(acpi_handle handle)
 839 {
 840         struct acpi_device *adev;
 841
 842         /*
 843          * Fixed hardware devices do not appear in the namespace and do not
 844          * have handles, but we fabricate acpi_devices for them, so we have
 845          * to deal with them specially.
 846          */
 847         if (!handle)
 848                 return acpi_root;
 849
 850         do {
 851                 acpi_status status;
 852
 853                 status = acpi_get_parent(handle, &handle);
 854                 if (ACPI_FAILURE(status)) {
 855                         if (status != AE_NULL_ENTRY)
 856                                 return acpi_root;
 857
 858                         return NULL;
 859                 }
 860                 adev = acpi_fetch_acpi_dev(handle);
 861         } while (!adev);
 862         return adev;
 863 }
 864
 865 acpi_status
 866 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
 867 {
 868         acpi_status status;
 869         acpi_handle tmp;
 870         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
 871         union acpi_object *obj;
 872
 873         status = acpi_get_handle(handle, "_EJD", &tmp);
 874         if (ACPI_FAILURE(status))
 875                 return status;
 876
 877         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
 878         if (ACPI_SUCCESS(status)) {
 879                 obj = buffer.pointer;
 880                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
 881                                          ejd);
 882                 kfree(buffer.pointer);
 883         }
 884         return status;
 885 }
 886 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
 887
 888 static int acpi_bus_extract_wakeup_device_power_package(struct acpi_device *dev)
 889 {
 890         acpi_handle handle = dev->handle;
 891         struct acpi_device_wakeup *wakeup = &dev->wakeup;
 892         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 893         union acpi_object *package = NULL;
 894         union acpi_object *element = NULL;
 895         acpi_status status;
 896         int err = -ENODATA;
 897
 898         INIT_LIST_HEAD(&wakeup->resources);
 899
 900         /* _PRW */
 901         status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
 902         if (ACPI_FAILURE(status)) {
 903                 acpi_handle_info(handle, "_PRW evaluation failed: %s\n",
 904                                  acpi_format_exception(status));
 905                 return err;
 906         }
 907
 908         package = (union acpi_object *)buffer.pointer;
 909
 910         if (!package || package->package.count < 2)
 911                 goto out;
 912
 913         element = &(package->package.elements[0]);
 914         if (!element)
 915                 goto out;
 916
 917         if (element->type == ACPI_TYPE_PACKAGE) {
 918                 if ((element->package.count < 2) ||
 919                     (element->package.elements[0].type !=
 920                      ACPI_TYPE_LOCAL_REFERENCE)
 921                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
 922                         goto out;
 923
 924                 wakeup->gpe_device =
 925                     element->package.elements[0].reference.handle;
 926                 wakeup->gpe_number =
 927                     (u32) element->package.elements[1].integer.value;
 928         } else if (element->type == ACPI_TYPE_INTEGER) {
 929                 wakeup->gpe_device = NULL;
 930                 wakeup->gpe_number = element->integer.value;
 931         } else {
 932                 goto out;
 933         }
 934
 935         element = &(package->package.elements[1]);
 936         if (element->type != ACPI_TYPE_INTEGER)
 937                 goto out;
 938
 939         wakeup->sleep_state = element->integer.value;
 940
 941         err = acpi_extract_power_resources(package, 2, &wakeup->resources);
 942         if (err)
 943                 goto out;
 944
 945         if (!list_empty(&wakeup->resources)) {
 946                 int sleep_state;
 947
 948                 err = acpi_power_wakeup_list_init(&wakeup->resources,
 949                                                   &sleep_state);
 950                 if (err) {
 951                         acpi_handle_warn(handle, "Retrieving current states "
 952                                          "of wakeup power resources failed\n");
 953                         acpi_power_resources_list_free(&wakeup->resources);
 954                         goto out;
 955                 }
 956                 if (sleep_state < wakeup->sleep_state) {
 957                         acpi_handle_warn(handle, "Overriding _PRW sleep state "
 958                                          "(S%d) by S%d from power resources\n",
 959                                          (int)wakeup->sleep_state, sleep_state);
 960                         wakeup->sleep_state = sleep_state;
 961                 }
 962         }
 963
 964  out:
 965         kfree(buffer.pointer);
 966         return err;
 967 }
 968
 969 /* Do not use a button for S5 wakeup */
 970 #define ACPI_AVOID_WAKE_FROM_S5         BIT(0)
 971
 972 static bool acpi_wakeup_gpe_init(struct acpi_device *device)
 973 {
 974         static const struct acpi_device_id button_device_ids[] = {
 975                 {"PNP0C0C", 0},                         /* Power button */
 976                 {"PNP0C0D", ACPI_AVOID_WAKE_FROM_S5},   /* Lid */
 977                 {"PNP0C0E", ACPI_AVOID_WAKE_FROM_S5},   /* Sleep button */
 978                 {"", 0},
 979         };
 980         struct acpi_device_wakeup *wakeup = &device->wakeup;
 981         const struct acpi_device_id *match;
 982         acpi_status status;
 983
 984         wakeup->flags.notifier_present = 0;
 985
 986         /* Power button, Lid switch always enable wakeup */
 987         match = acpi_match_acpi_device(button_device_ids, device);
 988         if (match) {
 989                 if ((match->driver_data & ACPI_AVOID_WAKE_FROM_S5) &&
 990                     wakeup->sleep_state == ACPI_STATE_S5)
 991                         wakeup->sleep_state = ACPI_STATE_S4;
 992                 acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
 993                 device_set_wakeup_capable(&device->dev, true);
 994                 return true;
 995         }
 996
 997         status = acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
 998                                          wakeup->gpe_number);
 999         return ACPI_SUCCESS(status);
1000 }
1001
1002 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
1003 {
1004         int err;
1005
1006         /* Presence of _PRW indicates wake capable */
1007         if (!acpi_has_method(device->handle, "_PRW"))
1008                 return;
1009
1010         err = acpi_bus_extract_wakeup_device_power_package(device);
1011         if (err) {
1012                 dev_err(&device->dev, "Unable to extract wakeup power resources");
1013                 return;
1014         }
1015
1016         device->wakeup.flags.valid = acpi_wakeup_gpe_init(device);
1017         device->wakeup.prepare_count = 0;
1018         /*
1019          * Call _PSW/_DSW object to disable its ability to wake the sleeping
1020          * system for the ACPI device with the _PRW object.
1021          * The _PSW object is deprecated in ACPI 3.0 and is replaced by _DSW.
1022          * So it is necessary to call _DSW object first. Only when it is not
1023          * present will the _PSW object used.
1024          */
1025         err = acpi_device_sleep_wake(device, 0, 0, 0);
1026         if (err)
1027                 pr_debug("error in _DSW or _PSW evaluation\n");
1028 }
1029
1030 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
1031 {
1032         struct acpi_device_power_state *ps = &device->power.states[state];
1033         char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
1034         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1035         acpi_status status;
1036
1037         INIT_LIST_HEAD(&ps->resources);
1038
1039         /* Evaluate "_PRx" to get referenced power resources */
1040         status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
1041         if (ACPI_SUCCESS(status)) {
1042                 union acpi_object *package = buffer.pointer;
1043
1044                 if (buffer.length && package
1045                     && package->type == ACPI_TYPE_PACKAGE
1046                     && package->package.count)
1047                         acpi_extract_power_resources(package, 0, &ps->resources);
1048
1049                 ACPI_FREE(buffer.pointer);
1050         }
1051
1052         /* Evaluate "_PSx" to see if we can do explicit sets */
1053         pathname[2] = 'S';
1054         if (acpi_has_method(device->handle, pathname))
1055                 ps->flags.explicit_set = 1;
1056
1057         /* State is valid if there are means to put the device into it. */
1058         if (!list_empty(&ps->resources) || ps->flags.explicit_set)
1059                 ps->flags.valid = 1;
1060
1061         ps->power = -1;         /* Unknown - driver assigned */
1062         ps->latency = -1;       /* Unknown - driver assigned */
1063 }
1064
1065 static void acpi_bus_get_power_flags(struct acpi_device *device)
1066 {
1067         unsigned long long dsc = ACPI_STATE_D0;
1068         u32 i;
1069
1070         /* Presence of _PS0|_PR0 indicates 'power manageable' */
1071         if (!acpi_has_method(device->handle, "_PS0") &&
1072             !acpi_has_method(device->handle, "_PR0"))
1073                 return;
1074
1075         device->flags.power_manageable = 1;
1076
1077         /*
1078          * Power Management Flags
1079          */
1080         if (acpi_has_method(device->handle, "_PSC"))
1081                 device->power.flags.explicit_get = 1;
1082
1083         if (acpi_has_method(device->handle, "_IRC"))
1084                 device->power.flags.inrush_current = 1;
1085
1086         if (acpi_has_method(device->handle, "_DSW"))
1087                 device->power.flags.dsw_present = 1;
1088
1089         acpi_evaluate_integer(device->handle, "_DSC", NULL, &dsc);
1090         device->power.state_for_enumeration = dsc;
1091
1092         /*
1093          * Enumerate supported power management states
1094          */
1095         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
1096                 acpi_bus_init_power_state(device, i);
1097
1098         INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
1099
1100         /* Set the defaults for D0 and D3hot (always supported). */
1101         device->power.states[ACPI_STATE_D0].flags.valid = 1;
1102         device->power.states[ACPI_STATE_D0].power = 100;
1103         device->power.states[ACPI_STATE_D3_HOT].flags.valid = 1;
1104
1105         /*
1106          * Use power resources only if the D0 list of them is populated, because
1107          * some platforms may provide _PR3 only to indicate D3cold support and
1108          * in those cases the power resources list returned by it may be bogus.
1109          */
1110         if (!list_empty(&device->power.states[ACPI_STATE_D0].resources)) {
1111                 device->power.flags.power_resources = 1;
1112                 /*
1113                  * D3cold is supported if the D3hot list of power resources is
1114                  * not empty.
1115                  */
1116                 if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources))
1117                         device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
1118         }
1119
1120         if (acpi_bus_init_power(device))
1121                 device->flags.power_manageable = 0;
1122 }
1123
1124 static void acpi_bus_get_flags(struct acpi_device *device)
1125 {
1126         /* Presence of _STA indicates 'dynamic_status' */
1127         if (acpi_has_method(device->handle, "_STA"))
1128                 device->flags.dynamic_status = 1;
1129
1130         /* Presence of _RMV indicates 'removable' */
1131         if (acpi_has_method(device->handle, "_RMV"))
1132                 device->flags.removable = 1;
1133
1134         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
1135         if (acpi_has_method(device->handle, "_EJD") ||
1136             acpi_has_method(device->handle, "_EJ0"))
1137                 device->flags.ejectable = 1;
1138 }
1139
1140 static void acpi_device_get_busid(struct acpi_device *device)
1141 {
1142         char bus_id[5] = { '?', 0 };
1143         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1144         int i = 0;
1145
1146         /*
1147          * Bus ID
1148          * ------
1149          * The device's Bus ID is simply the object name.
1150          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1151          */
1152         if (!acpi_dev_parent(device)) {
1153                 strcpy(device->pnp.bus_id, "ACPI");
1154                 return;
1155         }
1156
1157         switch (device->device_type) {
1158         case ACPI_BUS_TYPE_POWER_BUTTON:
1159                 strcpy(device->pnp.bus_id, "PWRF");
1160                 break;
1161         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1162                 strcpy(device->pnp.bus_id, "SLPF");
1163                 break;
1164         case ACPI_BUS_TYPE_ECDT_EC:
1165                 strcpy(device->pnp.bus_id, "ECDT");
1166                 break;
1167         default:
1168                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1169                 /* Clean up trailing underscores (if any) */
1170                 for (i = 3; i > 1; i--) {
1171                         if (bus_id[i] == '_')
1172                                 bus_id[i] = '\0';
1173                         else
1174                                 break;
1175                 }
1176                 strcpy(device->pnp.bus_id, bus_id);
1177                 break;
1178         }
1179 }
1180
1181 /*
1182  * acpi_ata_match - see if an acpi object is an ATA device
1183  *
1184  * If an acpi object has one of the ACPI ATA methods defined,
1185  * then we can safely call it an ATA device.
1186  */
1187 bool acpi_ata_match(acpi_handle handle)
1188 {
1189         return acpi_has_method(handle, "_GTF") ||
1190                acpi_has_method(handle, "_GTM") ||
1191                acpi_has_method(handle, "_STM") ||
1192                acpi_has_method(handle, "_SDD");
1193 }
1194
1195 /*
1196  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1197  *
1198  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1199  * then we can safely call it an ejectable drive bay
1200  */
1201 bool acpi_bay_match(acpi_handle handle)
1202 {
1203         acpi_handle phandle;
1204
1205         if (!acpi_has_method(handle, "_EJ0"))
1206                 return false;
1207         if (acpi_ata_match(handle))
1208                 return true;
1209         if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1210                 return false;
1211
1212         return acpi_ata_match(phandle);
1213 }
1214
1215 bool acpi_device_is_battery(struct acpi_device *adev)
1216 {
1217         struct acpi_hardware_id *hwid;
1218
1219         list_for_each_entry(hwid, &adev->pnp.ids, list)
1220                 if (!strcmp("PNP0C0A", hwid->id))
1221                         return true;
1222
1223         return false;
1224 }
1225
1226 static bool is_ejectable_bay(struct acpi_device *adev)
1227 {
1228         acpi_handle handle = adev->handle;
1229
1230         if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
1231                 return true;
1232
1233         return acpi_bay_match(handle);
1234 }
1235
1236 /*
1237  * acpi_dock_match - see if an acpi object has a _DCK method
1238  */
1239 bool acpi_dock_match(acpi_handle handle)
1240 {
1241         return acpi_has_method(handle, "_DCK");
1242 }
1243
1244 static acpi_status
1245 acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
1246                           void **return_value)
1247 {
1248         long *cap = context;
1249
1250         if (acpi_has_method(handle, "_BCM") &&
1251             acpi_has_method(handle, "_BCL")) {
1252                 acpi_handle_debug(handle, "Found generic backlight support\n");
1253                 *cap |= ACPI_VIDEO_BACKLIGHT;
1254                 /* We have backlight support, no need to scan further */
1255                 return AE_CTRL_TERMINATE;
1256         }
1257         return 0;
1258 }
1259
1260 /* Returns true if the ACPI object is a video device which can be
1261  * handled by video.ko.
1262  * The device will get a Linux specific CID added in scan.c to
1263  * identify the device as an ACPI graphics device
1264  * Be aware that the graphics device may not be physically present
1265  * Use acpi_video_get_capabilities() to detect general ACPI video
1266  * capabilities of present cards
1267  */
1268 long acpi_is_video_device(acpi_handle handle)
1269 {
1270         long video_caps = 0;
1271
1272         /* Is this device able to support video switching ? */
1273         if (acpi_has_method(handle, "_DOD") || acpi_has_method(handle, "_DOS"))
1274                 video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
1275
1276         /* Is this device able to retrieve a video ROM ? */
1277         if (acpi_has_method(handle, "_ROM"))
1278                 video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
1279
1280         /* Is this device able to configure which video head to be POSTed ? */
1281         if (acpi_has_method(handle, "_VPO") &&
1282             acpi_has_method(handle, "_GPD") &&
1283             acpi_has_method(handle, "_SPD"))
1284                 video_caps |= ACPI_VIDEO_DEVICE_POSTING;
1285
1286         /* Only check for backlight functionality if one of the above hit. */
1287         if (video_caps)
1288                 acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
1289                                     ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
1290                                     &video_caps, NULL);
1291
1292         return video_caps;
1293 }
1294 EXPORT_SYMBOL(acpi_is_video_device);
1295
1296 const char *acpi_device_hid(struct acpi_device *device)
1297 {
1298         struct acpi_hardware_id *hid;
1299
1300         hid = list_first_entry_or_null(&device->pnp.ids, struct acpi_hardware_id, list);
1301         if (!hid)
1302                 return dummy_hid;
1303
1304         return hid->id;
1305 }
1306 EXPORT_SYMBOL(acpi_device_hid);
1307
1308 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1309 {
1310         struct acpi_hardware_id *id;
1311
1312         id = kmalloc(sizeof(*id), GFP_KERNEL);
1313         if (!id)
1314                 return;
1315
1316         id->id = kstrdup_const(dev_id, GFP_KERNEL);
1317         if (!id->id) {
1318                 kfree(id);
1319                 return;
1320         }
1321
1322         list_add_tail(&id->list, &pnp->ids);
1323         pnp->type.hardware_id = 1;
1324 }
1325
1326 /*
1327  * Old IBM workstations have a DSDT bug wherein the SMBus object
1328  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1329  * prefix.  Work around this.
1330  */
1331 static bool acpi_ibm_smbus_match(acpi_handle handle)
1332 {
1333         char node_name[ACPI_PATH_SEGMENT_LENGTH];
1334         struct acpi_buffer path = { sizeof(node_name), node_name };
1335
1336         if (!dmi_name_in_vendors("IBM"))
1337                 return false;
1338
1339         /* Look for SMBS object */
1340         if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1341             strcmp("SMBS", path.pointer))
1342                 return false;
1343
1344         /* Does it have the necessary (but misnamed) methods? */
1345         if (acpi_has_method(handle, "SBI") &&
1346             acpi_has_method(handle, "SBR") &&
1347             acpi_has_method(handle, "SBW"))
1348                 return true;
1349
1350         return false;
1351 }
1352
1353 static bool acpi_object_is_system_bus(acpi_handle handle)
1354 {
1355         acpi_handle tmp;
1356
1357         if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
1358             tmp == handle)
1359                 return true;
1360         if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
1361             tmp == handle)
1362                 return true;
1363
1364         return false;
1365 }
1366
1367 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1368                              int device_type)
1369 {
1370         struct acpi_device_info *info = NULL;
1371         struct acpi_pnp_device_id_list *cid_list;
1372         int i;
1373
1374         switch (device_type) {
1375         case ACPI_BUS_TYPE_DEVICE:
1376                 if (handle == ACPI_ROOT_OBJECT) {
1377                         acpi_add_id(pnp, ACPI_SYSTEM_HID);
1378                         break;
1379                 }
1380
1381                 acpi_get_object_info(handle, &info);
1382                 if (!info) {
1383                         pr_err("%s: Error reading device info\n", __func__);
1384                         return;
1385                 }
1386
1387                 if (info->valid & ACPI_VALID_HID) {
1388                         acpi_add_id(pnp, info->hardware_id.string);
1389                         pnp->type.platform_id = 1;
1390                 }
1391                 if (info->valid & ACPI_VALID_CID) {
1392                         cid_list = &info->compatible_id_list;
1393                         for (i = 0; i < cid_list->count; i++)
1394                                 acpi_add_id(pnp, cid_list->ids[i].string);
1395                 }
1396                 if (info->valid & ACPI_VALID_ADR) {
1397                         pnp->bus_address = info->address;
1398                         pnp->type.bus_address = 1;
1399                 }
1400                 if (info->valid & ACPI_VALID_UID)
1401                         pnp->unique_id = kstrdup(info->unique_id.string,
1402                                                         GFP_KERNEL);
1403                 if (info->valid & ACPI_VALID_CLS)
1404                         acpi_add_id(pnp, info->class_code.string);
1405
1406                 kfree(info);
1407
1408                 /*
1409                  * Some devices don't reliably have _HIDs & _CIDs, so add
1410                  * synthetic HIDs to make sure drivers can find them.
1411                  */
1412                 if (acpi_is_video_device(handle)) {
1413                         acpi_add_id(pnp, ACPI_VIDEO_HID);
1414                         pnp->type.backlight = 1;
1415                         break;
1416                 }
1417                 if (acpi_bay_match(handle))
1418                         acpi_add_id(pnp, ACPI_BAY_HID);
1419                 else if (acpi_dock_match(handle))
1420                         acpi_add_id(pnp, ACPI_DOCK_HID);
1421                 else if (acpi_ibm_smbus_match(handle))
1422                         acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1423                 else if (list_empty(&pnp->ids) &&
1424                          acpi_object_is_system_bus(handle)) {
1425                         /* \_SB, \_TZ, LNXSYBUS */
1426                         acpi_add_id(pnp, ACPI_BUS_HID);
1427                         strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1428                         strcpy(pnp->device_class, ACPI_BUS_CLASS);
1429                 }
1430
1431                 break;
1432         case ACPI_BUS_TYPE_POWER:
1433                 acpi_add_id(pnp, ACPI_POWER_HID);
1434                 break;
1435         case ACPI_BUS_TYPE_PROCESSOR:
1436                 acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1437                 break;
1438         case ACPI_BUS_TYPE_THERMAL:
1439                 acpi_add_id(pnp, ACPI_THERMAL_HID);
1440                 break;
1441         case ACPI_BUS_TYPE_POWER_BUTTON:
1442                 acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1443                 break;
1444         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1445                 acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1446                 break;
1447         case ACPI_BUS_TYPE_ECDT_EC:
1448                 acpi_add_id(pnp, ACPI_ECDT_HID);
1449                 break;
1450         }
1451 }
1452
1453 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1454 {
1455         struct acpi_hardware_id *id, *tmp;
1456
1457         list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1458                 kfree_const(id->id);
1459                 kfree(id);
1460         }
1461         kfree(pnp->unique_id);
1462 }
1463
1464 /**
1465  * acpi_dma_supported - Check DMA support for the specified device.
1466  * @adev: The pointer to acpi device
1467  *
1468  * Return false if DMA is not supported. Otherwise, return true
1469  */
1470 bool acpi_dma_supported(const struct acpi_device *adev)
1471 {
1472         if (!adev)
1473                 return false;
1474
1475         if (adev->flags.cca_seen)
1476                 return true;
1477
1478         /*
1479         * Per ACPI 6.0 sec 6.2.17, assume devices can do cache-coherent
1480         * DMA on "Intel platforms".  Presumably that includes all x86 and
1481         * ia64, and other arches will set CONFIG_ACPI_CCA_REQUIRED=y.
1482         */
1483         if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1484                 return true;
1485
1486         return false;
1487 }
1488
1489 /**
1490  * acpi_get_dma_attr - Check the supported DMA attr for the specified device.
1491  * @adev: The pointer to acpi device
1492  *
1493  * Return enum dev_dma_attr.
1494  */
1495 enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
1496 {
1497         if (!acpi_dma_supported(adev))
1498                 return DEV_DMA_NOT_SUPPORTED;
1499
1500         if (adev->flags.coherent_dma)
1501                 return DEV_DMA_COHERENT;
1502         else
1503                 return DEV_DMA_NON_COHERENT;
1504 }
1505
1506 /**
1507  * acpi_dma_get_range() - Get device DMA parameters.
1508  *
1509  * @dev: device to configure
1510  * @map: pointer to DMA ranges result
1511  *
1512  * Evaluate DMA regions and return pointer to DMA regions on
1513  * parsing success; it does not update the passed in values on failure.
1514  *
1515  * Return 0 on success, < 0 on failure.
1516  */
1517 int acpi_dma_get_range(struct device *dev, const struct bus_dma_region **map)
1518 {
1519         struct acpi_device *adev;
1520         LIST_HEAD(list);
1521         struct resource_entry *rentry;
1522         int ret;
1523         struct device *dma_dev = dev;
1524         struct bus_dma_region *r;
1525
1526         /*
1527          * Walk the device tree chasing an ACPI companion with a _DMA
1528          * object while we go. Stop if we find a device with an ACPI
1529          * companion containing a _DMA method.
1530          */
1531         do {
1532                 adev = ACPI_COMPANION(dma_dev);
1533                 if (adev && acpi_has_method(adev->handle, METHOD_NAME__DMA))
1534                         break;
1535
1536                 dma_dev = dma_dev->parent;
1537         } while (dma_dev);
1538
1539         if (!dma_dev)
1540                 return -ENODEV;
1541
1542         if (!acpi_has_method(adev->handle, METHOD_NAME__CRS)) {
1543                 acpi_handle_warn(adev->handle, "_DMA is valid only if _CRS is present\n");
1544                 return -EINVAL;
1545         }
1546
1547         ret = acpi_dev_get_dma_resources(adev, &list);
1548         if (ret > 0) {
1549                 r = kcalloc(ret + 1, sizeof(*r), GFP_KERNEL);
1550                 if (!r) {
1551                         ret = -ENOMEM;
1552                         goto out;
1553                 }
1554
1555                 *map = r;
1556
1557                 list_for_each_entry(rentry, &list, node) {
1558                         if (rentry->res->start >= rentry->res->end) {
1559                                 kfree(*map);
1560                                 *map = NULL;
1561                                 ret = -EINVAL;
1562                                 dev_dbg(dma_dev, "Invalid DMA regions configuration\n");
1563                                 goto out;
1564                         }
1565
1566                         r->cpu_start = rentry->res->start;
1567                         r->dma_start = rentry->res->start - rentry->offset;
1568                         r->size = resource_size(rentry->res);
1569                         r++;
1570                 }
1571         }
1572  out:
1573         acpi_dev_free_resource_list(&list);
1574
1575         return ret >= 0 ? 0 : ret;
1576 }
1577
1578 #ifdef CONFIG_IOMMU_API
1579 int acpi_iommu_fwspec_init(struct device *dev, u32 id,
1580                            struct fwnode_handle *fwnode,
1581                            const struct iommu_ops *ops)
1582 {
1583         int ret;
1584
1585         ret = iommu_fwspec_init(dev, fwnode, ops);
1586         if (ret)
1587                 return ret;
1588
1589         return iommu_fwspec_add_ids(dev, &id, 1);
1590 }
1591
1592 static inline const struct iommu_ops *acpi_iommu_fwspec_ops(struct device *dev)
1593 {
1594         struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
1595
1596         return fwspec ? fwspec->ops : NULL;
1597 }
1598
1599 static int acpi_iommu_configure_id(struct device *dev, const u32 *id_in)
1600 {
1601         int err;
1602         const struct iommu_ops *ops;
1603
1604         /* Serialise to make dev->iommu stable under our potential fwspec */
1605         mutex_lock(&iommu_probe_device_lock);
1606         /*
1607          * If we already translated the fwspec there is nothing left to do,
1608          * return the iommu_ops.
1609          */
1610         ops = acpi_iommu_fwspec_ops(dev);
1611         if (ops) {
1612                 mutex_unlock(&iommu_probe_device_lock);
1613                 return 0;
1614         }
1615
1616         err = iort_iommu_configure_id(dev, id_in);
1617         if (err && err != -EPROBE_DEFER)
1618                 err = viot_iommu_configure(dev);
1619         mutex_unlock(&iommu_probe_device_lock);
1620
1621         /*
1622          * If we have reason to believe the IOMMU driver missed the initial
1623          * iommu_probe_device() call for dev, replay it to get things in order.
1624          */
1625         if (!err && dev->bus)
1626                 err = iommu_probe_device(dev);
1627
1628         if (err == -EPROBE_DEFER)
1629                 return err;
1630         if (err) {
1631                 dev_dbg(dev, "Adding to IOMMU failed: %d\n", err);
1632                 return err;
1633         }
1634         if (!acpi_iommu_fwspec_ops(dev))
1635                 return -ENODEV;
1636         return 0;
1637 }
1638
1639 #else /* !CONFIG_IOMMU_API */
1640
1641 int acpi_iommu_fwspec_init(struct device *dev, u32 id,
1642                            struct fwnode_handle *fwnode,
1643                            const struct iommu_ops *ops)
1644 {
1645         return -ENODEV;
1646 }
1647
1648 static int acpi_iommu_configure_id(struct device *dev, const u32 *id_in)
1649 {
1650         return -ENODEV;
1651 }
1652
1653 #endif /* !CONFIG_IOMMU_API */
1654
1655 /**
1656  * acpi_dma_configure_id - Set-up DMA configuration for the device.
1657  * @dev: The pointer to the device
1658  * @attr: device dma attributes
1659  * @input_id: input device id const value pointer
1660  */
1661 int acpi_dma_configure_id(struct device *dev, enum dev_dma_attr attr,
1662                           const u32 *input_id)
1663 {
1664         int ret;
1665
1666         if (attr == DEV_DMA_NOT_SUPPORTED) {
1667                 set_dma_ops(dev, &dma_dummy_ops);
1668                 return 0;
1669         }
1670
1671         acpi_arch_dma_setup(dev);
1672
1673         /* Ignore all other errors apart from EPROBE_DEFER */
1674         ret = acpi_iommu_configure_id(dev, input_id);
1675         if (ret == -EPROBE_DEFER)
1676                 return -EPROBE_DEFER;
1677
1678         arch_setup_dma_ops(dev, attr == DEV_DMA_COHERENT);
1679
1680         return 0;
1681 }
1682 EXPORT_SYMBOL_GPL(acpi_dma_configure_id);
1683
1684 static void acpi_init_coherency(struct acpi_device *adev)
1685 {
1686         unsigned long long cca = 0;
1687         acpi_status status;
1688         struct acpi_device *parent = acpi_dev_parent(adev);
1689
1690         if (parent && parent->flags.cca_seen) {
1691                 /*
1692                  * From ACPI spec, OSPM will ignore _CCA if an ancestor
1693                  * already saw one.
1694                  */
1695                 adev->flags.cca_seen = 1;
1696                 cca = parent->flags.coherent_dma;
1697         } else {
1698                 status = acpi_evaluate_integer(adev->handle, "_CCA",
1699                                                NULL, &cca);
1700                 if (ACPI_SUCCESS(status))
1701                         adev->flags.cca_seen = 1;
1702                 else if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1703                         /*
1704                          * If architecture does not specify that _CCA is
1705                          * required for DMA-able devices (e.g. x86),
1706                          * we default to _CCA=1.
1707                          */
1708                         cca = 1;
1709                 else
1710                         acpi_handle_debug(adev->handle,
1711                                           "ACPI device is missing _CCA.\n");
1712         }
1713
1714         adev->flags.coherent_dma = cca;
1715 }
1716
1717 static int acpi_check_serial_bus_slave(struct acpi_resource *ares, void *data)
1718 {
1719         bool *is_serial_bus_slave_p = data;
1720
1721         if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
1722                 return 1;
1723
1724         *is_serial_bus_slave_p = true;
1725
1726          /* no need to do more checking */
1727         return -1;
1728 }
1729
1730 static bool acpi_is_indirect_io_slave(struct acpi_device *device)
1731 {
1732         struct acpi_device *parent = acpi_dev_parent(device);
1733         static const struct acpi_device_id indirect_io_hosts[] = {
1734                 {"HISI0191", 0},
1735                 {}
1736         };
1737
1738         return parent && !acpi_match_device_ids(parent, indirect_io_hosts);
1739 }
1740
1741 static bool acpi_device_enumeration_by_parent(struct acpi_device *device)
1742 {
1743         struct list_head resource_list;
1744         bool is_serial_bus_slave = false;
1745         static const struct acpi_device_id ignore_serial_bus_ids[] = {
1746         /*
1747          * These devices have multiple SerialBus resources and a client
1748          * device must be instantiated for each of them, each with
1749          * its own device id.
1750          * Normally we only instantiate one client device for the first
1751          * resource, using the ACPI HID as id. These special cases are handled
1752          * by the drivers/platform/x86/serial-multi-instantiate.c driver, which
1753          * knows which client device id to use for each resource.
1754          */
1755                 {"BSG1160", },
1756                 {"BSG2150", },
1757                 {"CSC3551", },
1758                 {"CSC3554", },
1759                 {"CSC3556", },
1760                 {"CSC3557", },
1761                 {"INT33FE", },
1762                 {"INT3515", },
1763                 /* Non-conforming _HID for Cirrus Logic already released */
1764                 {"CLSA0100", },
1765                 {"CLSA0101", },
1766         /*
1767          * Some ACPI devs contain SerialBus resources even though they are not
1768          * attached to a serial bus at all.
1769          */
1770                 {ACPI_VIDEO_HID, },
1771                 {"MSHW0028", },
1772         /*
1773          * HIDs of device with an UartSerialBusV2 resource for which userspace
1774          * expects a regular tty cdev to be created (instead of the in kernel
1775          * serdev) and which have a kernel driver which expects a platform_dev
1776          * such as the rfkill-gpio driver.
1777          */
1778                 {"BCM4752", },
1779                 {"LNV4752", },
1780                 {}
1781         };
1782
1783         if (acpi_is_indirect_io_slave(device))
1784                 return true;
1785
1786         /* Macs use device properties in lieu of _CRS resources */
1787         if (x86_apple_machine &&
1788             (fwnode_property_present(&device->fwnode, "spiSclkPeriod") ||
1789              fwnode_property_present(&device->fwnode, "i2cAddress") ||
1790              fwnode_property_present(&device->fwnode, "baud")))
1791                 return true;
1792
1793         if (!acpi_match_device_ids(device, ignore_serial_bus_ids))
1794                 return false;
1795
1796         INIT_LIST_HEAD(&resource_list);
1797         acpi_dev_get_resources(device, &resource_list,
1798                                acpi_check_serial_bus_slave,
1799                                &is_serial_bus_slave);
1800         acpi_dev_free_resource_list(&resource_list);
1801
1802         return is_serial_bus_slave;
1803 }
1804
1805 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1806                              int type, void (*release)(struct device *))
1807 {
1808         struct acpi_device *parent = acpi_find_parent_acpi_dev(handle);
1809
1810         INIT_LIST_HEAD(&device->pnp.ids);
1811         device->device_type = type;
1812         device->handle = handle;
1813         device->dev.parent = parent ? &parent->dev : NULL;
1814         device->dev.release = release;
1815         device->dev.bus = &acpi_bus_type;
1816         fwnode_init(&device->fwnode, &acpi_device_fwnode_ops);
1817         acpi_set_device_status(device, ACPI_STA_DEFAULT);
1818         acpi_device_get_busid(device);
1819         acpi_set_pnp_ids(handle, &device->pnp, type);
1820         acpi_init_properties(device);
1821         acpi_bus_get_flags(device);
1822         device->flags.match_driver = false;
1823         device->flags.initialized = true;
1824         device->flags.enumeration_by_parent =
1825                 acpi_device_enumeration_by_parent(device);
1826         acpi_device_clear_enumerated(device);
1827         device_initialize(&device->dev);
1828         dev_set_uevent_suppress(&device->dev, true);
1829         acpi_init_coherency(device);
1830 }
1831
1832 static void acpi_scan_dep_init(struct acpi_device *adev)
1833 {
1834         struct acpi_dep_data *dep;
1835
1836         list_for_each_entry(dep, &acpi_dep_list, node) {
1837                 if (dep->consumer == adev->handle) {
1838                         if (dep->honor_dep)
1839                                 adev->flags.honor_deps = 1;
1840
1841                         if (!dep->met)
1842                                 adev->dep_unmet++;
1843                 }
1844         }
1845 }
1846
1847 void acpi_device_add_finalize(struct acpi_device *device)
1848 {
1849         dev_set_uevent_suppress(&device->dev, false);
1850         kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1851 }
1852
1853 static void acpi_scan_init_status(struct acpi_device *adev)
1854 {
1855         if (acpi_bus_get_status(adev))
1856                 acpi_set_device_status(adev, 0);
1857 }
1858
1859 static int acpi_add_single_object(struct acpi_device **child,
1860                                   acpi_handle handle, int type, bool dep_init)
1861 {
1862         struct acpi_device *device;
1863         bool release_dep_lock = false;
1864         int result;
1865
1866         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1867         if (!device)
1868                 return -ENOMEM;
1869
1870         acpi_init_device_object(device, handle, type, acpi_device_release);
1871         /*
1872          * Getting the status is delayed till here so that we can call
1873          * acpi_bus_get_status() and use its quirk handling.  Note that
1874          * this must be done before the get power-/wakeup_dev-flags calls.
1875          */
1876         if (type == ACPI_BUS_TYPE_DEVICE || type == ACPI_BUS_TYPE_PROCESSOR) {
1877                 if (dep_init) {
1878                         mutex_lock(&acpi_dep_list_lock);
1879                         /*
1880                          * Hold the lock until the acpi_tie_acpi_dev() call
1881                          * below to prevent concurrent acpi_scan_clear_dep()
1882                          * from deleting a dependency list entry without
1883                          * updating dep_unmet for the device.
1884                          */
1885                         release_dep_lock = true;
1886                         acpi_scan_dep_init(device);
1887                 }
1888                 acpi_scan_init_status(device);
1889         }
1890
1891         acpi_bus_get_power_flags(device);
1892         acpi_bus_get_wakeup_device_flags(device);
1893
1894         result = acpi_tie_acpi_dev(device);
1895
1896         if (release_dep_lock)
1897                 mutex_unlock(&acpi_dep_list_lock);
1898
1899         if (!result)
1900                 result = acpi_device_add(device);
1901
1902         if (result) {
1903                 acpi_device_release(&device->dev);
1904                 return result;
1905         }
1906
1907         acpi_power_add_remove_device(device, true);
1908         acpi_device_add_finalize(device);
1909
1910         acpi_handle_debug(handle, "Added as %s, parent %s\n",
1911                           dev_name(&device->dev), device->dev.parent ?
1912                                 dev_name(device->dev.parent) : "(null)");
1913
1914         *child = device;
1915         return 0;
1916 }
1917
1918 static acpi_status acpi_get_resource_memory(struct acpi_resource *ares,
1919                                             void *context)
1920 {
1921         struct resource *res = context;
1922
1923         if (acpi_dev_resource_memory(ares, res))
1924                 return AE_CTRL_TERMINATE;
1925
1926         return AE_OK;
1927 }
1928
1929 static bool acpi_device_should_be_hidden(acpi_handle handle)
1930 {
1931         acpi_status status;
1932         struct resource res;
1933
1934         /* Check if it should ignore the UART device */
1935         if (!(spcr_uart_addr && acpi_has_method(handle, METHOD_NAME__CRS)))
1936                 return false;
1937
1938         /*
1939          * The UART device described in SPCR table is assumed to have only one
1940          * memory resource present. So we only look for the first one here.
1941          */
1942         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1943                                      acpi_get_resource_memory, &res);
1944         if (ACPI_FAILURE(status) || res.start != spcr_uart_addr)
1945                 return false;
1946
1947         acpi_handle_info(handle, "The UART device @%pa in SPCR table will be hidden\n",
1948                          &res.start);
1949
1950         return true;
1951 }
1952
1953 bool acpi_device_is_present(const struct acpi_device *adev)
1954 {
1955         return adev->status.present || adev->status.functional;
1956 }
1957
1958 bool acpi_device_is_enabled(const struct acpi_device *adev)
1959 {
1960         return adev->status.enabled;
1961 }
1962
1963 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1964                                        const char *idstr,
1965                                        const struct acpi_device_id **matchid)
1966 {
1967         const struct acpi_device_id *devid;
1968
1969         if (handler->match)
1970                 return handler->match(idstr, matchid);
1971
1972         for (devid = handler->ids; devid->id[0]; devid++)
1973                 if (!strcmp((char *)devid->id, idstr)) {
1974                         if (matchid)
1975                                 *matchid = devid;
1976
1977                         return true;
1978                 }
1979
1980         return false;
1981 }
1982
1983 static struct acpi_scan_handler *acpi_scan_match_handler(const char *idstr,
1984                                         const struct acpi_device_id **matchid)
1985 {
1986         struct acpi_scan_handler *handler;
1987
1988         list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1989                 if (acpi_scan_handler_matching(handler, idstr, matchid))
1990                         return handler;
1991
1992         return NULL;
1993 }
1994
1995 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1996 {
1997         if (!!hotplug->enabled == !!val)
1998                 return;
1999
2000         mutex_lock(&acpi_scan_lock);
2001
2002         hotplug->enabled = val;
2003
2004         mutex_unlock(&acpi_scan_lock);
2005 }
2006
2007 static void acpi_scan_init_hotplug(struct acpi_device *adev)
2008 {
2009         struct acpi_hardware_id *hwid;
2010
2011         if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
2012                 acpi_dock_add(adev);
2013                 return;
2014         }
2015         list_for_each_entry(hwid, &adev->pnp.ids, list) {
2016                 struct acpi_scan_handler *handler;
2017
2018                 handler = acpi_scan_match_handler(hwid->id, NULL);
2019                 if (handler) {
2020                         adev->flags.hotplug_notify = true;
2021                         break;
2022                 }
2023         }
2024 }
2025
2026 static u32 acpi_scan_check_dep(acpi_handle handle)
2027 {
2028         struct acpi_handle_list dep_devices;
2029         u32 count;
2030         int i;
2031
2032         /*
2033          * Check for _HID here to avoid deferring the enumeration of:
2034          * 1. PCI devices.
2035          * 2. ACPI nodes describing USB ports.
2036          * Still, checking for _HID catches more then just these cases ...
2037          */
2038         if (!acpi_has_method(handle, "_DEP") || !acpi_has_method(handle, "_HID"))
2039                 return 0;
2040
2041         if (!acpi_evaluate_reference(handle, "_DEP", NULL, &dep_devices)) {
2042                 acpi_handle_debug(handle, "Failed to evaluate _DEP.\n");
2043                 return 0;
2044         }
2045
2046         for (count = 0, i = 0; i < dep_devices.count; i++) {
2047                 struct acpi_device_info *info;
2048                 struct acpi_dep_data *dep;
2049                 bool skip, honor_dep;
2050                 acpi_status status;
2051
2052                 status = acpi_get_object_info(dep_devices.handles[i], &info);
2053                 if (ACPI_FAILURE(status)) {
2054                         acpi_handle_debug(handle, "Error reading _DEP device info\n");
2055                         continue;
2056                 }
2057
2058                 skip = acpi_info_matches_ids(info, acpi_ignore_dep_ids);
2059                 honor_dep = acpi_info_matches_ids(info, acpi_honor_dep_ids);
2060                 kfree(info);
2061
2062                 if (skip)
2063                         continue;
2064
2065                 dep = kzalloc(sizeof(*dep), GFP_KERNEL);
2066                 if (!dep)
2067                         continue;
2068
2069                 count++;
2070
2071                 dep->supplier = dep_devices.handles[i];
2072                 dep->consumer = handle;
2073                 dep->honor_dep = honor_dep;
2074
2075                 mutex_lock(&acpi_dep_list_lock);
2076                 list_add_tail(&dep->node , &acpi_dep_list);
2077                 mutex_unlock(&acpi_dep_list_lock);
2078         }
2079
2080         acpi_handle_list_free(&dep_devices);
2081         return count;
2082 }
2083
2084 static acpi_status acpi_scan_check_crs_csi2_cb(acpi_handle handle, u32 a, void *b, void **c)
2085 {
2086         acpi_mipi_check_crs_csi2(handle);
2087         return AE_OK;
2088 }
2089
2090 static acpi_status acpi_bus_check_add(acpi_handle handle, bool first_pass,
2091                                       struct acpi_device **adev_p)
2092 {
2093         struct acpi_device *device = acpi_fetch_acpi_dev(handle);
2094         acpi_object_type acpi_type;
2095         int type;
2096
2097         if (device)
2098                 goto out;
2099
2100         if (ACPI_FAILURE(acpi_get_type(handle, &acpi_type)))
2101                 return AE_OK;
2102
2103         switch (acpi_type) {
2104         case ACPI_TYPE_DEVICE:
2105                 if (acpi_device_should_be_hidden(handle))
2106                         return AE_OK;
2107
2108                 if (first_pass) {
2109                         acpi_mipi_check_crs_csi2(handle);
2110
2111                         /* Bail out if there are dependencies. */
2112                         if (acpi_scan_check_dep(handle) > 0) {
2113                                 /*
2114                                  * The entire CSI-2 connection graph needs to be
2115                                  * extracted before any drivers or scan handlers
2116                                  * are bound to struct device objects, so scan
2117                                  * _CRS CSI-2 resource descriptors for all
2118                                  * devices below the current handle.
2119                                  */
2120                                 acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
2121                                                     ACPI_UINT32_MAX,
2122                                                     acpi_scan_check_crs_csi2_cb,
2123                                                     NULL, NULL, NULL);
2124                                 return AE_CTRL_DEPTH;
2125                         }
2126                 }
2127
2128                 fallthrough;
2129         case ACPI_TYPE_ANY:     /* for ACPI_ROOT_OBJECT */
2130                 type = ACPI_BUS_TYPE_DEVICE;
2131                 break;
2132
2133         case ACPI_TYPE_PROCESSOR:
2134                 type = ACPI_BUS_TYPE_PROCESSOR;
2135                 break;
2136
2137         case ACPI_TYPE_THERMAL:
2138                 type = ACPI_BUS_TYPE_THERMAL;
2139                 break;
2140
2141         case ACPI_TYPE_POWER:
2142                 acpi_add_power_resource(handle);
2143                 fallthrough;
2144         default:
2145                 return AE_OK;
2146         }
2147
2148         /*
2149          * If first_pass is true at this point, the device has no dependencies,
2150          * or the creation of the device object would have been postponed above.
2151          */
2152         acpi_add_single_object(&device, handle, type, !first_pass);
2153         if (!device)
2154                 return AE_CTRL_DEPTH;
2155
2156         acpi_scan_init_hotplug(device);
2157
2158 out:
2159         if (!*adev_p)
2160                 *adev_p = device;
2161
2162         return AE_OK;
2163 }
2164
2165 static acpi_status acpi_bus_check_add_1(acpi_handle handle, u32 lvl_not_used,
2166                                         void *not_used, void **ret_p)
2167 {
2168         return acpi_bus_check_add(handle, true, (struct acpi_device **)ret_p);
2169 }
2170
2171 static acpi_status acpi_bus_check_add_2(acpi_handle handle, u32 lvl_not_used,
2172                                         void *not_used, void **ret_p)
2173 {
2174         return acpi_bus_check_add(handle, false, (struct acpi_device **)ret_p);
2175 }
2176
2177 static void acpi_default_enumeration(struct acpi_device *device)
2178 {
2179         /*
2180          * Do not enumerate devices with enumeration_by_parent flag set as
2181          * they will be enumerated by their respective parents.
2182          */
2183         if (!device->flags.enumeration_by_parent) {
2184                 acpi_create_platform_device(device, NULL);
2185                 acpi_device_set_enumerated(device);
2186         } else {
2187                 blocking_notifier_call_chain(&acpi_reconfig_chain,
2188                                              ACPI_RECONFIG_DEVICE_ADD, device);
2189         }
2190 }
2191
2192 static const struct acpi_device_id generic_device_ids[] = {
2193         {ACPI_DT_NAMESPACE_HID, },
2194         {"", },
2195 };
2196
2197 static int acpi_generic_device_attach(struct acpi_device *adev,
2198                                       const struct acpi_device_id *not_used)
2199 {
2200         /*
2201          * Since ACPI_DT_NAMESPACE_HID is the only ID handled here, the test
2202          * below can be unconditional.
2203          */
2204         if (adev->data.of_compatible)
2205                 acpi_default_enumeration(adev);
2206
2207         return 1;
2208 }
2209
2210 static struct acpi_scan_handler generic_device_handler = {
2211         .ids = generic_device_ids,
2212         .attach = acpi_generic_device_attach,
2213 };
2214
2215 static int acpi_scan_attach_handler(struct acpi_device *device)
2216 {
2217         struct acpi_hardware_id *hwid;
2218         int ret = 0;
2219
2220         list_for_each_entry(hwid, &device->pnp.ids, list) {
2221                 const struct acpi_device_id *devid;
2222                 struct acpi_scan_handler *handler;
2223
2224                 handler = acpi_scan_match_handler(hwid->id, &devid);
2225                 if (handler) {
2226                         if (!handler->attach) {
2227                                 device->pnp.type.platform_id = 0;
2228                                 continue;
2229                         }
2230                         device->handler = handler;
2231                         ret = handler->attach(device, devid);
2232                         if (ret > 0)
2233                                 break;
2234
2235                         device->handler = NULL;
2236                         if (ret < 0)
2237                                 break;
2238                 }
2239         }
2240
2241         return ret;
2242 }
2243
2244 static int acpi_bus_attach(struct acpi_device *device, void *first_pass)
2245 {
2246         bool skip = !first_pass && device->flags.visited;
2247         acpi_handle ejd;
2248         int ret;
2249
2250         if (skip)
2251                 goto ok;
2252
2253         if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
2254                 register_dock_dependent_device(device, ejd);
2255
2256         acpi_bus_get_status(device);
2257         /* Skip devices that are not ready for enumeration (e.g. not present) */
2258         if (!acpi_dev_ready_for_enumeration(device)) {
2259                 device->flags.initialized = false;
2260                 acpi_device_clear_enumerated(device);
2261                 device->flags.power_manageable = 0;
2262                 return 0;
2263         }
2264         if (device->handler)
2265                 goto ok;
2266
2267         if (!device->flags.initialized) {
2268                 device->flags.power_manageable =
2269                         device->power.states[ACPI_STATE_D0].flags.valid;
2270                 if (acpi_bus_init_power(device))
2271                         device->flags.power_manageable = 0;
2272
2273                 device->flags.initialized = true;
2274         } else if (device->flags.visited) {
2275                 goto ok;
2276         }
2277
2278         ret = acpi_scan_attach_handler(device);
2279         if (ret < 0)
2280                 return 0;
2281
2282         device->flags.match_driver = true;
2283         if (ret > 0 && !device->flags.enumeration_by_parent) {
2284                 acpi_device_set_enumerated(device);
2285                 goto ok;
2286         }
2287
2288         ret = device_attach(&device->dev);
2289         if (ret < 0)
2290                 return 0;
2291
2292         if (device->pnp.type.platform_id || device->flags.enumeration_by_parent)
2293                 acpi_default_enumeration(device);
2294         else
2295                 acpi_device_set_enumerated(device);
2296
2297 ok:
2298         acpi_dev_for_each_child(device, acpi_bus_attach, first_pass);
2299
2300         if (!skip && device->handler && device->handler->hotplug.notify_online)
2301                 device->handler->hotplug.notify_online(device);
2302
2303         return 0;
2304 }
2305
2306 static int acpi_dev_get_next_consumer_dev_cb(struct acpi_dep_data *dep, void *data)
2307 {
2308         struct acpi_device **adev_p = data;
2309         struct acpi_device *adev = *adev_p;
2310
2311         /*
2312          * If we're passed a 'previous' consumer device then we need to skip
2313          * any consumers until we meet the previous one, and then NULL @data
2314          * so the next one can be returned.
2315          */
2316         if (adev) {
2317                 if (dep->consumer == adev->handle)
2318                         *adev_p = NULL;
2319
2320                 return 0;
2321         }
2322
2323         adev = acpi_get_acpi_dev(dep->consumer);
2324         if (adev) {
2325                 *(struct acpi_device **)data = adev;
2326                 return 1;
2327         }
2328         /* Continue parsing if the device object is not present. */
2329         return 0;
2330 }
2331
2332 struct acpi_scan_clear_dep_work {
2333         struct work_struct work;
2334         struct acpi_device *adev;
2335 };
2336
2337 static void acpi_scan_clear_dep_fn(struct work_struct *work)
2338 {
2339         struct acpi_scan_clear_dep_work *cdw;
2340
2341         cdw = container_of(work, struct acpi_scan_clear_dep_work, work);
2342
2343         acpi_scan_lock_acquire();
2344         acpi_bus_attach(cdw->adev, (void *)true);
2345         acpi_scan_lock_release();
2346
2347         acpi_dev_put(cdw->adev);
2348         kfree(cdw);
2349 }
2350
2351 static bool acpi_scan_clear_dep_queue(struct acpi_device *adev)
2352 {
2353         struct acpi_scan_clear_dep_work *cdw;
2354
2355         if (adev->dep_unmet)
2356                 return false;
2357
2358         cdw = kmalloc(sizeof(*cdw), GFP_KERNEL);
2359         if (!cdw)
2360                 return false;
2361
2362         cdw->adev = adev;
2363         INIT_WORK(&cdw->work, acpi_scan_clear_dep_fn);
2364         /*
2365          * Since the work function may block on the lock until the entire
2366          * initial enumeration of devices is complete, put it into the unbound
2367          * workqueue.
2368          */
2369         queue_work(system_unbound_wq, &cdw->work);
2370
2371         return true;
2372 }
2373
2374 static void acpi_scan_delete_dep_data(struct acpi_dep_data *dep)
2375 {
2376         list_del(&dep->node);
2377         kfree(dep);
2378 }
2379
2380 static int acpi_scan_clear_dep(struct acpi_dep_data *dep, void *data)
2381 {
2382         struct acpi_device *adev = acpi_get_acpi_dev(dep->consumer);
2383
2384         if (adev) {
2385                 adev->dep_unmet--;
2386                 if (!acpi_scan_clear_dep_queue(adev))
2387                         acpi_dev_put(adev);
2388         }
2389
2390         if (dep->free_when_met)
2391                 acpi_scan_delete_dep_data(dep);
2392         else
2393                 dep->met = true;
2394
2395         return 0;
2396 }
2397
2398 /**
2399  * acpi_walk_dep_device_list - Apply a callback to every entry in acpi_dep_list
2400  * @handle:     The ACPI handle of the supplier device
2401  * @callback:   Pointer to the callback function to apply
2402  * @data:       Pointer to some data to pass to the callback
2403  *
2404  * The return value of the callback determines this function's behaviour. If 0
2405  * is returned we continue to iterate over acpi_dep_list. If a positive value
2406  * is returned then the loop is broken but this function returns 0. If a
2407  * negative value is returned by the callback then the loop is broken and that
2408  * value is returned as the final error.
2409  */
2410 static int acpi_walk_dep_device_list(acpi_handle handle,
2411                                 int (*callback)(struct acpi_dep_data *, void *),
2412                                 void *data)
2413 {
2414         struct acpi_dep_data *dep, *tmp;
2415         int ret = 0;
2416
2417         mutex_lock(&acpi_dep_list_lock);
2418         list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
2419                 if (dep->supplier == handle) {
2420                         ret = callback(dep, data);
2421                         if (ret)
2422                                 break;
2423                 }
2424         }
2425         mutex_unlock(&acpi_dep_list_lock);
2426
2427         return ret > 0 ? 0 : ret;
2428 }
2429
2430 /**
2431  * acpi_dev_clear_dependencies - Inform consumers that the device is now active
2432  * @supplier: Pointer to the supplier &struct acpi_device
2433  *
2434  * Clear dependencies on the given device.
2435  */
2436 void acpi_dev_clear_dependencies(struct acpi_device *supplier)
2437 {
2438         acpi_walk_dep_device_list(supplier->handle, acpi_scan_clear_dep, NULL);
2439 }
2440 EXPORT_SYMBOL_GPL(acpi_dev_clear_dependencies);
2441
2442 /**
2443  * acpi_dev_ready_for_enumeration - Check if the ACPI device is ready for enumeration
2444  * @device: Pointer to the &struct acpi_device to check
2445  *
2446  * Check if the device is present and has no unmet dependencies.
2447  *
2448  * Return true if the device is ready for enumeratino. Otherwise, return false.
2449  */
2450 bool acpi_dev_ready_for_enumeration(const struct acpi_device *device)
2451 {
2452         if (device->flags.honor_deps && device->dep_unmet)
2453                 return false;
2454
2455         return acpi_device_is_present(device);
2456 }
2457 EXPORT_SYMBOL_GPL(acpi_dev_ready_for_enumeration);
2458
2459 /**
2460  * acpi_dev_get_next_consumer_dev - Return the next adev dependent on @supplier
2461  * @supplier: Pointer to the dependee device
2462  * @start: Pointer to the current dependent device
2463  *
2464  * Returns the next &struct acpi_device which declares itself dependent on
2465  * @supplier via the _DEP buffer, parsed from the acpi_dep_list.
2466  *
2467  * If the returned adev is not passed as @start to this function, the caller is
2468  * responsible for putting the reference to adev when it is no longer needed.
2469  */
2470 struct acpi_device *acpi_dev_get_next_consumer_dev(struct acpi_device *supplier,
2471                                                    struct acpi_device *start)
2472 {
2473         struct acpi_device *adev = start;
2474
2475         acpi_walk_dep_device_list(supplier->handle,
2476                                   acpi_dev_get_next_consumer_dev_cb, &adev);
2477
2478         acpi_dev_put(start);
2479
2480         if (adev == start)
2481                 return NULL;
2482
2483         return adev;
2484 }
2485 EXPORT_SYMBOL_GPL(acpi_dev_get_next_consumer_dev);
2486
2487 static void acpi_scan_postponed_branch(acpi_handle handle)
2488 {
2489         struct acpi_device *adev = NULL;
2490
2491         if (ACPI_FAILURE(acpi_bus_check_add(handle, false, &adev)))
2492                 return;
2493
2494         acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2495                             acpi_bus_check_add_2, NULL, NULL, (void **)&adev);
2496
2497         /*
2498          * Populate the ACPI _CRS CSI-2 software nodes for the ACPI devices that
2499          * have been added above.
2500          */
2501         acpi_mipi_init_crs_csi2_swnodes();
2502
2503         acpi_bus_attach(adev, NULL);
2504 }
2505
2506 static void acpi_scan_postponed(void)
2507 {
2508         struct acpi_dep_data *dep, *tmp;
2509
2510         mutex_lock(&acpi_dep_list_lock);
2511
2512         list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
2513                 acpi_handle handle = dep->consumer;
2514
2515                 /*
2516                  * In case there are multiple acpi_dep_list entries with the
2517                  * same consumer, skip the current entry if the consumer device
2518                  * object corresponding to it is present already.
2519                  */
2520                 if (!acpi_fetch_acpi_dev(handle)) {
2521                         /*
2522                          * Even though the lock is released here, tmp is
2523                          * guaranteed to be valid, because none of the list
2524                          * entries following dep is marked as "free when met"
2525                          * and so they cannot be deleted.
2526                          */
2527                         mutex_unlock(&acpi_dep_list_lock);
2528
2529                         acpi_scan_postponed_branch(handle);
2530
2531                         mutex_lock(&acpi_dep_list_lock);
2532                 }
2533
2534                 if (dep->met)
2535                         acpi_scan_delete_dep_data(dep);
2536                 else
2537                         dep->free_when_met = true;
2538         }
2539
2540         mutex_unlock(&acpi_dep_list_lock);
2541 }
2542
2543 /**
2544  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
2545  * @handle: Root of the namespace scope to scan.
2546  *
2547  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
2548  * found devices.
2549  *
2550  * If no devices were found, -ENODEV is returned, but it does not mean that
2551  * there has been a real error.  There just have been no suitable ACPI objects
2552  * in the table trunk from which the kernel could create a device and add an
2553  * appropriate driver.
2554  *
2555  * Must be called under acpi_scan_lock.
2556  */
2557 int acpi_bus_scan(acpi_handle handle)
2558 {
2559         struct acpi_device *device = NULL;
2560
2561         /* Pass 1: Avoid enumerating devices with missing dependencies. */
2562
2563         if (ACPI_SUCCESS(acpi_bus_check_add(handle, true, &device)))
2564                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2565                                     acpi_bus_check_add_1, NULL, NULL,
2566                                     (void **)&device);
2567
2568         if (!device)
2569                 return -ENODEV;
2570
2571         /*
2572          * Set up ACPI _CRS CSI-2 software nodes using information extracted
2573          * from the _CRS CSI-2 resource descriptors during the ACPI namespace
2574          * walk above and MIPI DisCo for Imaging device properties.
2575          */
2576         acpi_mipi_scan_crs_csi2();
2577         acpi_mipi_init_crs_csi2_swnodes();
2578
2579         acpi_bus_attach(device, (void *)true);
2580
2581         /* Pass 2: Enumerate all of the remaining devices. */
2582
2583         acpi_scan_postponed();
2584
2585         acpi_mipi_crs_csi2_cleanup();
2586
2587         return 0;
2588 }
2589 EXPORT_SYMBOL(acpi_bus_scan);
2590
2591 /**
2592  * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
2593  * @adev: Root of the ACPI namespace scope to walk.
2594  *
2595  * Must be called under acpi_scan_lock.
2596  */
2597 void acpi_bus_trim(struct acpi_device *adev)
2598 {
2599         acpi_scan_check_and_detach(adev, NULL);
2600 }
2601 EXPORT_SYMBOL_GPL(acpi_bus_trim);
2602
2603 int acpi_bus_register_early_device(int type)
2604 {
2605         struct acpi_device *device = NULL;
2606         int result;
2607
2608         result = acpi_add_single_object(&device, NULL, type, false);
2609         if (result)
2610                 return result;
2611
2612         device->flags.match_driver = true;
2613         return device_attach(&device->dev);
2614 }
2615 EXPORT_SYMBOL_GPL(acpi_bus_register_early_device);
2616
2617 static void acpi_bus_scan_fixed(void)
2618 {
2619         if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2620                 struct acpi_device *adev = NULL;
2621
2622                 acpi_add_single_object(&adev, NULL, ACPI_BUS_TYPE_POWER_BUTTON,
2623                                        false);
2624                 if (adev) {
2625                         adev->flags.match_driver = true;
2626                         if (device_attach(&adev->dev) >= 0)
2627                                 device_init_wakeup(&adev->dev, true);
2628                         else
2629                                 dev_dbg(&adev->dev, "No driver\n");
2630                 }
2631         }
2632
2633         if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2634                 struct acpi_device *adev = NULL;
2635
2636                 acpi_add_single_object(&adev, NULL, ACPI_BUS_TYPE_SLEEP_BUTTON,
2637                                        false);
2638                 if (adev) {
2639                         adev->flags.match_driver = true;
2640                         if (device_attach(&adev->dev) < 0)
2641                                 dev_dbg(&adev->dev, "No driver\n");
2642                 }
2643         }
2644 }
2645
2646 static void __init acpi_get_spcr_uart_addr(void)
2647 {
2648         acpi_status status;
2649         struct acpi_table_spcr *spcr_ptr;
2650
2651         status = acpi_get_table(ACPI_SIG_SPCR, 0,
2652                                 (struct acpi_table_header **)&spcr_ptr);
2653         if (ACPI_FAILURE(status)) {
2654                 pr_warn("STAO table present, but SPCR is missing\n");
2655                 return;
2656         }
2657
2658         spcr_uart_addr = spcr_ptr->serial_port.address;
2659         acpi_put_table((struct acpi_table_header *)spcr_ptr);
2660 }
2661
2662 static bool acpi_scan_initialized;
2663
2664 void __init acpi_scan_init(void)
2665 {
2666         acpi_status status;
2667         struct acpi_table_stao *stao_ptr;
2668
2669         acpi_pci_root_init();
2670         acpi_pci_link_init();
2671         acpi_processor_init();
2672         acpi_platform_init();
2673         acpi_lpss_init();
2674         acpi_apd_init();
2675         acpi_cmos_rtc_init();
2676         acpi_container_init();
2677         acpi_memory_hotplug_init();
2678         acpi_watchdog_init();
2679         acpi_pnp_init();
2680         acpi_int340x_thermal_init();
2681         acpi_init_lpit();
2682
2683         acpi_scan_add_handler(&generic_device_handler);
2684
2685         /*
2686          * If there is STAO table, check whether it needs to ignore the UART
2687          * device in SPCR table.
2688          */
2689         status = acpi_get_table(ACPI_SIG_STAO, 0,
2690                                 (struct acpi_table_header **)&stao_ptr);
2691         if (ACPI_SUCCESS(status)) {
2692                 if (stao_ptr->header.length > sizeof(struct acpi_table_stao))
2693                         pr_info("STAO Name List not yet supported.\n");
2694
2695                 if (stao_ptr->ignore_uart)
2696                         acpi_get_spcr_uart_addr();
2697
2698                 acpi_put_table((struct acpi_table_header *)stao_ptr);
2699         }
2700
2701         acpi_gpe_apply_masked_gpes();
2702         acpi_update_all_gpes();
2703
2704         /*
2705          * Although we call __add_memory() that is documented to require the
2706          * device_hotplug_lock, it is not necessary here because this is an
2707          * early code when userspace or any other code path cannot trigger
2708          * hotplug/hotunplug operations.
2709          */
2710         mutex_lock(&acpi_scan_lock);
2711         /*
2712          * Enumerate devices in the ACPI namespace.
2713          */
2714         if (acpi_bus_scan(ACPI_ROOT_OBJECT))
2715                 goto unlock;
2716
2717         acpi_root = acpi_fetch_acpi_dev(ACPI_ROOT_OBJECT);
2718         if (!acpi_root)
2719                 goto unlock;
2720
2721         /* Fixed feature devices do not exist on HW-reduced platform */
2722         if (!acpi_gbl_reduced_hardware)
2723                 acpi_bus_scan_fixed();
2724
2725         acpi_turn_off_unused_power_resources();
2726
2727         acpi_scan_initialized = true;
2728
2729 unlock:
2730         mutex_unlock(&acpi_scan_lock);
2731 }
2732
2733 static struct acpi_probe_entry *ape;
2734 static int acpi_probe_count;
2735 static DEFINE_MUTEX(acpi_probe_mutex);
2736
2737 static int __init acpi_match_madt(union acpi_subtable_headers *header,
2738                                   const unsigned long end)
2739 {
2740         if (!ape->subtable_valid || ape->subtable_valid(&header->common, ape))
2741                 if (!ape->probe_subtbl(header, end))
2742                         acpi_probe_count++;
2743
2744         return 0;
2745 }
2746
2747 int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr)
2748 {
2749         int count = 0;
2750
2751         if (acpi_disabled)
2752                 return 0;
2753
2754         mutex_lock(&acpi_probe_mutex);
2755         for (ape = ap_head; nr; ape++, nr--) {
2756                 if (ACPI_COMPARE_NAMESEG(ACPI_SIG_MADT, ape->id)) {
2757                         acpi_probe_count = 0;
2758                         acpi_table_parse_madt(ape->type, acpi_match_madt, 0);
2759                         count += acpi_probe_count;
2760                 } else {
2761                         int res;
2762                         res = acpi_table_parse(ape->id, ape->probe_table);
2763                         if (!res)
2764                                 count++;
2765                 }
2766         }
2767         mutex_unlock(&acpi_probe_mutex);
2768
2769         return count;
2770 }
2771
2772 static void acpi_table_events_fn(struct work_struct *work)
2773 {
2774         acpi_scan_lock_acquire();
2775         acpi_bus_scan(ACPI_ROOT_OBJECT);
2776         acpi_scan_lock_release();
2777
2778         kfree(work);
2779 }
2780
2781 void acpi_scan_table_notify(void)
2782 {
2783         struct work_struct *work;
2784
2785         if (!acpi_scan_initialized)
2786                 return;
2787
2788         work = kmalloc(sizeof(*work), GFP_KERNEL);
2789         if (!work)
2790                 return;
2791
2792         INIT_WORK(work, acpi_table_events_fn);
2793         schedule_work(work);
2794 }
2795
2796 int acpi_reconfig_notifier_register(struct notifier_block *nb)
2797 {
2798         return blocking_notifier_chain_register(&acpi_reconfig_chain, nb);
2799 }
2800 EXPORT_SYMBOL(acpi_reconfig_notifier_register);
2801
2802 int acpi_reconfig_notifier_unregister(struct notifier_block *nb)
2803 {
2804         return blocking_notifier_chain_unregister(&acpi_reconfig_chain, nb);
2805 }
2806 EXPORT_SYMBOL(acpi_reconfig_notifier_unregister);