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); 2807