1 // SPDX-License-Identifier: GPL-2.0-only
3 * scan.c - support for transforming the ACPI namespace into individual objects
6 #define pr_fmt(fmt) "ACPI: " fmt
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/nls.h>
20 #include <linux/dma-map-ops.h>
21 #include <linux/platform_data/x86/apple.h>
22 #include <linux/pgtable.h>
26 extern struct acpi_device *acpi_root;
28 #define ACPI_BUS_CLASS "system_bus"
29 #define ACPI_BUS_HID "LNXSYBUS"
30 #define ACPI_BUS_DEVICE_NAME "System Bus"
32 #define ACPI_IS_ROOT_DEVICE(device) (!(device)->parent)
34 #define INVALID_ACPI_HANDLE ((acpi_handle)empty_zero_page)
36 static const char *dummy_hid = "device";
38 static LIST_HEAD(acpi_dep_list);
39 static DEFINE_MUTEX(acpi_dep_list_lock);
40 LIST_HEAD(acpi_bus_id_list);
41 static DEFINE_MUTEX(acpi_scan_lock);
42 static LIST_HEAD(acpi_scan_handlers_list);
43 DEFINE_MUTEX(acpi_device_lock);
44 LIST_HEAD(acpi_wakeup_device_list);
45 static DEFINE_MUTEX(acpi_hp_context_lock);
48 * The UART device described by the SPCR table is the only object which needs
49 * special-casing. Everything else is covered by ACPI namespace paths in STAO
52 static u64 spcr_uart_addr;
54 void acpi_scan_lock_acquire(void)
56 mutex_lock(&acpi_scan_lock);
58 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
60 void acpi_scan_lock_release(void)
62 mutex_unlock(&acpi_scan_lock);
64 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
66 void acpi_lock_hp_context(void)
68 mutex_lock(&acpi_hp_context_lock);
71 void acpi_unlock_hp_context(void)
73 mutex_unlock(&acpi_hp_context_lock);
76 void acpi_initialize_hp_context(struct acpi_device *adev,
77 struct acpi_hotplug_context *hp,
78 int (*notify)(struct acpi_device *, u32),
79 void (*uevent)(struct acpi_device *, u32))
81 acpi_lock_hp_context();
84 acpi_set_hp_context(adev, hp);
85 acpi_unlock_hp_context();
87 EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
89 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
94 list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
98 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
99 const char *hotplug_profile_name)
103 error = acpi_scan_add_handler(handler);
107 acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
111 bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
113 struct acpi_device_physical_node *pn;
115 char *envp[] = { "EVENT=offline", NULL };
118 * acpi_container_offline() calls this for all of the container's
119 * children under the container's physical_node_lock lock.
121 mutex_lock_nested(&adev->physical_node_lock, SINGLE_DEPTH_NESTING);
123 list_for_each_entry(pn, &adev->physical_node_list, node)
124 if (device_supports_offline(pn->dev) && !pn->dev->offline) {
126 kobject_uevent_env(&pn->dev->kobj, KOBJ_CHANGE, envp);
132 mutex_unlock(&adev->physical_node_lock);
136 static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
139 struct acpi_device *device = NULL;
140 struct acpi_device_physical_node *pn;
141 bool second_pass = (bool)data;
142 acpi_status status = AE_OK;
144 if (acpi_bus_get_device(handle, &device))
147 if (device->handler && !device->handler->hotplug.enabled) {
148 *ret_p = &device->dev;
152 mutex_lock(&device->physical_node_lock);
154 list_for_each_entry(pn, &device->physical_node_list, node) {
158 /* Skip devices offlined by the first pass. */
162 pn->put_online = false;
164 ret = device_offline(pn->dev);
166 pn->put_online = !ret;
176 mutex_unlock(&device->physical_node_lock);
181 static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
184 struct acpi_device *device = NULL;
185 struct acpi_device_physical_node *pn;
187 if (acpi_bus_get_device(handle, &device))
190 mutex_lock(&device->physical_node_lock);
192 list_for_each_entry(pn, &device->physical_node_list, node)
193 if (pn->put_online) {
194 device_online(pn->dev);
195 pn->put_online = false;
198 mutex_unlock(&device->physical_node_lock);
203 static int acpi_scan_try_to_offline(struct acpi_device *device)
205 acpi_handle handle = device->handle;
206 struct device *errdev = NULL;
210 * Carry out two passes here and ignore errors in the first pass,
211 * because if the devices in question are memory blocks and
212 * CONFIG_MEMCG is set, one of the blocks may hold data structures
213 * that the other blocks depend on, but it is not known in advance which
216 * If the first pass is successful, the second one isn't needed, though.
218 status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
219 NULL, acpi_bus_offline, (void *)false,
221 if (status == AE_SUPPORT) {
222 dev_warn(errdev, "Offline disabled.\n");
223 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
224 acpi_bus_online, NULL, NULL, NULL);
227 acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
230 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
231 NULL, acpi_bus_offline, (void *)true,
234 acpi_bus_offline(handle, 0, (void *)true,
238 dev_warn(errdev, "Offline failed.\n");
239 acpi_bus_online(handle, 0, NULL, NULL);
240 acpi_walk_namespace(ACPI_TYPE_ANY, handle,
241 ACPI_UINT32_MAX, acpi_bus_online,
249 static int acpi_scan_hot_remove(struct acpi_device *device)
251 acpi_handle handle = device->handle;
252 unsigned long long sta;
255 if (device->handler && device->handler->hotplug.demand_offline) {
256 if (!acpi_scan_is_offline(device, true))
259 int error = acpi_scan_try_to_offline(device);
264 acpi_handle_debug(handle, "Ejecting\n");
266 acpi_bus_trim(device);
268 acpi_evaluate_lck(handle, 0);
272 status = acpi_evaluate_ej0(handle);
273 if (status == AE_NOT_FOUND)
275 else if (ACPI_FAILURE(status))
279 * Verify if eject was indeed successful. If not, log an error
280 * message. No need to call _OST since _EJ0 call was made OK.
282 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
283 if (ACPI_FAILURE(status)) {
284 acpi_handle_warn(handle,
285 "Status check after eject failed (0x%x)\n", status);
286 } else if (sta & ACPI_STA_DEVICE_ENABLED) {
287 acpi_handle_warn(handle,
288 "Eject incomplete - status 0x%llx\n", sta);
294 static int acpi_scan_device_not_present(struct acpi_device *adev)
296 if (!acpi_device_enumerated(adev)) {
297 dev_warn(&adev->dev, "Still not present\n");
304 static int acpi_scan_device_check(struct acpi_device *adev)
308 acpi_bus_get_status(adev);
309 if (adev->status.present || adev->status.functional) {
311 * This function is only called for device objects for which
312 * matching scan handlers exist. The only situation in which
313 * the scan handler is not attached to this device object yet
314 * is when the device has just appeared (either it wasn't
315 * present at all before or it was removed and then added
319 dev_warn(&adev->dev, "Already enumerated\n");
322 error = acpi_bus_scan(adev->handle);
324 dev_warn(&adev->dev, "Namespace scan failure\n");
327 if (!adev->handler) {
328 dev_warn(&adev->dev, "Enumeration failure\n");
332 error = acpi_scan_device_not_present(adev);
337 static int acpi_scan_bus_check(struct acpi_device *adev)
339 struct acpi_scan_handler *handler = adev->handler;
340 struct acpi_device *child;
343 acpi_bus_get_status(adev);
344 if (!(adev->status.present || adev->status.functional)) {
345 acpi_scan_device_not_present(adev);
348 if (handler && handler->hotplug.scan_dependent)
349 return handler->hotplug.scan_dependent(adev);
351 error = acpi_bus_scan(adev->handle);
353 dev_warn(&adev->dev, "Namespace scan failure\n");
356 list_for_each_entry(child, &adev->children, node) {
357 error = acpi_scan_bus_check(child);
364 static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type)
367 case ACPI_NOTIFY_BUS_CHECK:
368 return acpi_scan_bus_check(adev);
369 case ACPI_NOTIFY_DEVICE_CHECK:
370 return acpi_scan_device_check(adev);
371 case ACPI_NOTIFY_EJECT_REQUEST:
372 case ACPI_OST_EC_OSPM_EJECT:
373 if (adev->handler && !adev->handler->hotplug.enabled) {
374 dev_info(&adev->dev, "Eject disabled\n");
377 acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST,
378 ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
379 return acpi_scan_hot_remove(adev);
384 void acpi_device_hotplug(struct acpi_device *adev, u32 src)
386 u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
389 lock_device_hotplug();
390 mutex_lock(&acpi_scan_lock);
393 * The device object's ACPI handle cannot become invalid as long as we
394 * are holding acpi_scan_lock, but it might have become invalid before
395 * that lock was acquired.
397 if (adev->handle == INVALID_ACPI_HANDLE)
400 if (adev->flags.is_dock_station) {
401 error = dock_notify(adev, src);
402 } else if (adev->flags.hotplug_notify) {
403 error = acpi_generic_hotplug_event(adev, src);
405 int (*notify)(struct acpi_device *, u32);
407 acpi_lock_hp_context();
408 notify = adev->hp ? adev->hp->notify : NULL;
409 acpi_unlock_hp_context();
411 * There may be additional notify handlers for device objects
412 * without the .event() callback, so ignore them here.
415 error = notify(adev, src);
421 ost_code = ACPI_OST_SC_SUCCESS;
424 ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
427 ost_code = ACPI_OST_SC_DEVICE_BUSY;
430 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
435 acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
438 acpi_bus_put_acpi_device(adev);
439 mutex_unlock(&acpi_scan_lock);
440 unlock_device_hotplug();
443 static void acpi_free_power_resources_lists(struct acpi_device *device)
447 if (device->wakeup.flags.valid)
448 acpi_power_resources_list_free(&device->wakeup.resources);
450 if (!device->power.flags.power_resources)
453 for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
454 struct acpi_device_power_state *ps = &device->power.states[i];
455 acpi_power_resources_list_free(&ps->resources);
459 static void acpi_device_release(struct device *dev)
461 struct acpi_device *acpi_dev = to_acpi_device(dev);
463 acpi_free_properties(acpi_dev);
464 acpi_free_pnp_ids(&acpi_dev->pnp);
465 acpi_free_power_resources_lists(acpi_dev);
469 static void acpi_device_del(struct acpi_device *device)
471 struct acpi_device_bus_id *acpi_device_bus_id;
473 mutex_lock(&acpi_device_lock);
475 list_del(&device->node);
477 list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node)
478 if (!strcmp(acpi_device_bus_id->bus_id,
479 acpi_device_hid(device))) {
480 ida_simple_remove(&acpi_device_bus_id->instance_ida, device->pnp.instance_no);
481 if (ida_is_empty(&acpi_device_bus_id->instance_ida)) {
482 list_del(&acpi_device_bus_id->node);
483 kfree_const(acpi_device_bus_id->bus_id);
484 kfree(acpi_device_bus_id);
489 list_del(&device->wakeup_list);
490 mutex_unlock(&acpi_device_lock);
492 acpi_power_add_remove_device(device, false);
493 acpi_device_remove_files(device);
495 device->remove(device);
497 device_del(&device->dev);
500 static BLOCKING_NOTIFIER_HEAD(acpi_reconfig_chain);
502 static LIST_HEAD(acpi_device_del_list);
503 static DEFINE_MUTEX(acpi_device_del_lock);
505 static void acpi_device_del_work_fn(struct work_struct *work_not_used)
508 struct acpi_device *adev;
510 mutex_lock(&acpi_device_del_lock);
512 if (list_empty(&acpi_device_del_list)) {
513 mutex_unlock(&acpi_device_del_lock);
516 adev = list_first_entry(&acpi_device_del_list,
517 struct acpi_device, del_list);
518 list_del(&adev->del_list);
520 mutex_unlock(&acpi_device_del_lock);
522 blocking_notifier_call_chain(&acpi_reconfig_chain,
523 ACPI_RECONFIG_DEVICE_REMOVE, adev);
525 acpi_device_del(adev);
527 * Drop references to all power resources that might have been
528 * used by the device.
530 acpi_power_transition(adev, ACPI_STATE_D3_COLD);
536 * acpi_scan_drop_device - Drop an ACPI device object.
537 * @handle: Handle of an ACPI namespace node, not used.
538 * @context: Address of the ACPI device object to drop.
540 * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
541 * namespace node the device object pointed to by @context is attached to.
543 * The unregistration is carried out asynchronously to avoid running
544 * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
545 * ensure the correct ordering (the device objects must be unregistered in the
546 * same order in which the corresponding namespace nodes are deleted).
548 static void acpi_scan_drop_device(acpi_handle handle, void *context)
550 static DECLARE_WORK(work, acpi_device_del_work_fn);
551 struct acpi_device *adev = context;
553 mutex_lock(&acpi_device_del_lock);
556 * Use the ACPI hotplug workqueue which is ordered, so this work item
557 * won't run after any hotplug work items submitted subsequently. That
558 * prevents attempts to register device objects identical to those being
559 * deleted from happening concurrently (such attempts result from
560 * hotplug events handled via the ACPI hotplug workqueue). It also will
561 * run after all of the work items submitted previously, which helps
562 * those work items to ensure that they are not accessing stale device
565 if (list_empty(&acpi_device_del_list))
566 acpi_queue_hotplug_work(&work);
568 list_add_tail(&adev->del_list, &acpi_device_del_list);
569 /* Make acpi_ns_validate_handle() return NULL for this handle. */
570 adev->handle = INVALID_ACPI_HANDLE;
572 mutex_unlock(&acpi_device_del_lock);
575 static struct acpi_device *handle_to_device(acpi_handle handle,
576 void (*callback)(void *))
578 struct acpi_device *adev = NULL;
581 status = acpi_get_data_full(handle, acpi_scan_drop_device,
582 (void **)&adev, callback);
583 if (ACPI_FAILURE(status) || !adev) {
584 acpi_handle_debug(handle, "No context!\n");
590 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
595 *device = handle_to_device(handle, NULL);
601 EXPORT_SYMBOL(acpi_bus_get_device);
603 static void get_acpi_device(void *dev)
608 struct acpi_device *acpi_bus_get_acpi_device(acpi_handle handle)
610 return handle_to_device(handle, get_acpi_device);
613 static struct acpi_device_bus_id *acpi_device_bus_id_match(const char *dev_id)
615 struct acpi_device_bus_id *acpi_device_bus_id;
617 /* Find suitable bus_id and instance number in acpi_bus_id_list. */
618 list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
619 if (!strcmp(acpi_device_bus_id->bus_id, dev_id))
620 return acpi_device_bus_id;
625 static int acpi_device_set_name(struct acpi_device *device,
626 struct acpi_device_bus_id *acpi_device_bus_id)
628 struct ida *instance_ida = &acpi_device_bus_id->instance_ida;
631 result = ida_simple_get(instance_ida, 0, ACPI_MAX_DEVICE_INSTANCES, GFP_KERNEL);
635 device->pnp.instance_no = result;
636 dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, result);
640 static int acpi_tie_acpi_dev(struct acpi_device *adev)
642 acpi_handle handle = adev->handle;
648 status = acpi_attach_data(handle, acpi_scan_drop_device, adev);
649 if (ACPI_FAILURE(status)) {
650 acpi_handle_err(handle, "Unable to attach device data\n");
657 static int __acpi_device_add(struct acpi_device *device,
658 void (*release)(struct device *))
660 struct acpi_device_bus_id *acpi_device_bus_id;
666 * Link this device to its parent and siblings.
668 INIT_LIST_HEAD(&device->children);
669 INIT_LIST_HEAD(&device->node);
670 INIT_LIST_HEAD(&device->wakeup_list);
671 INIT_LIST_HEAD(&device->physical_node_list);
672 INIT_LIST_HEAD(&device->del_list);
673 mutex_init(&device->physical_node_lock);
675 mutex_lock(&acpi_device_lock);
677 acpi_device_bus_id = acpi_device_bus_id_match(acpi_device_hid(device));
678 if (acpi_device_bus_id) {
679 result = acpi_device_set_name(device, acpi_device_bus_id);
683 acpi_device_bus_id = kzalloc(sizeof(*acpi_device_bus_id),
685 if (!acpi_device_bus_id) {
689 acpi_device_bus_id->bus_id =
690 kstrdup_const(acpi_device_hid(device), GFP_KERNEL);
691 if (!acpi_device_bus_id->bus_id) {
692 kfree(acpi_device_bus_id);
697 ida_init(&acpi_device_bus_id->instance_ida);
699 result = acpi_device_set_name(device, acpi_device_bus_id);
701 kfree_const(acpi_device_bus_id->bus_id);
702 kfree(acpi_device_bus_id);
706 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
710 list_add_tail(&device->node, &device->parent->children);
712 if (device->wakeup.flags.valid)
713 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
715 mutex_unlock(&acpi_device_lock);
718 device->dev.parent = &device->parent->dev;
720 device->dev.bus = &acpi_bus_type;
721 device->dev.release = release;
722 result = device_add(&device->dev);
724 dev_err(&device->dev, "Error registering device\n");
728 result = acpi_device_setup_files(device);
730 pr_err("Error creating sysfs interface for device %s\n",
731 dev_name(&device->dev));
736 mutex_lock(&acpi_device_lock);
739 list_del(&device->node);
741 list_del(&device->wakeup_list);
744 mutex_unlock(&acpi_device_lock);
746 acpi_detach_data(device->handle, acpi_scan_drop_device);
751 int acpi_device_add(struct acpi_device *adev, void (*release)(struct device *))
755 ret = acpi_tie_acpi_dev(adev);
759 return __acpi_device_add(adev, release);
762 /* --------------------------------------------------------------------------
764 -------------------------------------------------------------------------- */
765 static bool acpi_info_matches_ids(struct acpi_device_info *info,
766 const char * const ids[])
768 struct acpi_pnp_device_id_list *cid_list = NULL;
771 if (!(info->valid & ACPI_VALID_HID))
774 index = match_string(ids, -1, info->hardware_id.string);
778 if (info->valid & ACPI_VALID_CID)
779 cid_list = &info->compatible_id_list;
784 for (i = 0; i < cid_list->count; i++) {
785 index = match_string(ids, -1, cid_list->ids[i].string);
793 /* List of HIDs for which we ignore matching ACPI devices, when checking _DEP lists. */
794 static const char * const acpi_ignore_dep_ids[] = {
795 "PNP0D80", /* Windows-compatible System Power Management Controller */
796 "INT33BD", /* Intel Baytrail Mailbox Device */
800 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
802 struct acpi_device *device = NULL;
806 * Fixed hardware devices do not appear in the namespace and do not
807 * have handles, but we fabricate acpi_devices for them, so we have
808 * to deal with them specially.
814 status = acpi_get_parent(handle, &handle);
815 if (ACPI_FAILURE(status))
816 return status == AE_NULL_ENTRY ? NULL : acpi_root;
817 } while (acpi_bus_get_device(handle, &device));
822 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
826 struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
827 union acpi_object *obj;
829 status = acpi_get_handle(handle, "_EJD", &tmp);
830 if (ACPI_FAILURE(status))
833 status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
834 if (ACPI_SUCCESS(status)) {
835 obj = buffer.pointer;
836 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
838 kfree(buffer.pointer);
842 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
844 static int acpi_bus_extract_wakeup_device_power_package(struct acpi_device *dev)
846 acpi_handle handle = dev->handle;
847 struct acpi_device_wakeup *wakeup = &dev->wakeup;
848 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
849 union acpi_object *package = NULL;
850 union acpi_object *element = NULL;
854 INIT_LIST_HEAD(&wakeup->resources);
857 status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
858 if (ACPI_FAILURE(status)) {
859 acpi_handle_info(handle, "_PRW evaluation failed: %s\n",
860 acpi_format_exception(status));
864 package = (union acpi_object *)buffer.pointer;
866 if (!package || package->package.count < 2)
869 element = &(package->package.elements[0]);
873 if (element->type == ACPI_TYPE_PACKAGE) {
874 if ((element->package.count < 2) ||
875 (element->package.elements[0].type !=
876 ACPI_TYPE_LOCAL_REFERENCE)
877 || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
881 element->package.elements[0].reference.handle;
883 (u32) element->package.elements[1].integer.value;
884 } else if (element->type == ACPI_TYPE_INTEGER) {
885 wakeup->gpe_device = NULL;
886 wakeup->gpe_number = element->integer.value;
891 element = &(package->package.elements[1]);
892 if (element->type != ACPI_TYPE_INTEGER)
895 wakeup->sleep_state = element->integer.value;
897 err = acpi_extract_power_resources(package, 2, &wakeup->resources);
901 if (!list_empty(&wakeup->resources)) {
904 err = acpi_power_wakeup_list_init(&wakeup->resources,
907 acpi_handle_warn(handle, "Retrieving current states "
908 "of wakeup power resources failed\n");
909 acpi_power_resources_list_free(&wakeup->resources);
912 if (sleep_state < wakeup->sleep_state) {
913 acpi_handle_warn(handle, "Overriding _PRW sleep state "
914 "(S%d) by S%d from power resources\n",
915 (int)wakeup->sleep_state, sleep_state);
916 wakeup->sleep_state = sleep_state;
921 kfree(buffer.pointer);
925 static bool acpi_wakeup_gpe_init(struct acpi_device *device)
927 static const struct acpi_device_id button_device_ids[] = {
928 {"PNP0C0C", 0}, /* Power button */
929 {"PNP0C0D", 0}, /* Lid */
930 {"PNP0C0E", 0}, /* Sleep button */
933 struct acpi_device_wakeup *wakeup = &device->wakeup;
936 wakeup->flags.notifier_present = 0;
938 /* Power button, Lid switch always enable wakeup */
939 if (!acpi_match_device_ids(device, button_device_ids)) {
940 if (!acpi_match_device_ids(device, &button_device_ids[1])) {
941 /* Do not use Lid/sleep button for S5 wakeup */
942 if (wakeup->sleep_state == ACPI_STATE_S5)
943 wakeup->sleep_state = ACPI_STATE_S4;
945 acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
946 device_set_wakeup_capable(&device->dev, true);
950 status = acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
952 return ACPI_SUCCESS(status);
955 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
959 /* Presence of _PRW indicates wake capable */
960 if (!acpi_has_method(device->handle, "_PRW"))
963 err = acpi_bus_extract_wakeup_device_power_package(device);
965 dev_err(&device->dev, "Unable to extract wakeup power resources");
969 device->wakeup.flags.valid = acpi_wakeup_gpe_init(device);
970 device->wakeup.prepare_count = 0;
972 * Call _PSW/_DSW object to disable its ability to wake the sleeping
973 * system for the ACPI device with the _PRW object.
974 * The _PSW object is deprecated in ACPI 3.0 and is replaced by _DSW.
975 * So it is necessary to call _DSW object first. Only when it is not
976 * present will the _PSW object used.
978 err = acpi_device_sleep_wake(device, 0, 0, 0);
980 pr_debug("error in _DSW or _PSW evaluation\n");
983 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
985 struct acpi_device_power_state *ps = &device->power.states[state];
986 char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
987 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
990 INIT_LIST_HEAD(&ps->resources);
992 /* Evaluate "_PRx" to get referenced power resources */
993 status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
994 if (ACPI_SUCCESS(status)) {
995 union acpi_object *package = buffer.pointer;
997 if (buffer.length && package
998 && package->type == ACPI_TYPE_PACKAGE
999 && package->package.count)
1000 acpi_extract_power_resources(package, 0, &ps->resources);
1002 ACPI_FREE(buffer.pointer);
1005 /* Evaluate "_PSx" to see if we can do explicit sets */
1007 if (acpi_has_method(device->handle, pathname))
1008 ps->flags.explicit_set = 1;
1010 /* State is valid if there are means to put the device into it. */
1011 if (!list_empty(&ps->resources) || ps->flags.explicit_set)
1012 ps->flags.valid = 1;
1014 ps->power = -1; /* Unknown - driver assigned */
1015 ps->latency = -1; /* Unknown - driver assigned */
1018 static void acpi_bus_get_power_flags(struct acpi_device *device)
1022 /* Presence of _PS0|_PR0 indicates 'power manageable' */
1023 if (!acpi_has_method(device->handle, "_PS0") &&
1024 !acpi_has_method(device->handle, "_PR0"))
1027 device->flags.power_manageable = 1;
1030 * Power Management Flags
1032 if (acpi_has_method(device->handle, "_PSC"))
1033 device->power.flags.explicit_get = 1;
1035 if (acpi_has_method(device->handle, "_IRC"))
1036 device->power.flags.inrush_current = 1;
1038 if (acpi_has_method(device->handle, "_DSW"))
1039 device->power.flags.dsw_present = 1;
1042 * Enumerate supported power management states
1044 for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
1045 acpi_bus_init_power_state(device, i);
1047 INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
1049 /* Set the defaults for D0 and D3hot (always supported). */
1050 device->power.states[ACPI_STATE_D0].flags.valid = 1;
1051 device->power.states[ACPI_STATE_D0].power = 100;
1052 device->power.states[ACPI_STATE_D3_HOT].flags.valid = 1;
1055 * Use power resources only if the D0 list of them is populated, because
1056 * some platforms may provide _PR3 only to indicate D3cold support and
1057 * in those cases the power resources list returned by it may be bogus.
1059 if (!list_empty(&device->power.states[ACPI_STATE_D0].resources)) {
1060 device->power.flags.power_resources = 1;
1062 * D3cold is supported if the D3hot list of power resources is
1065 if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources))
1066 device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
1069 if (acpi_bus_init_power(device))
1070 device->flags.power_manageable = 0;
1073 static void acpi_bus_get_flags(struct acpi_device *device)
1075 /* Presence of _STA indicates 'dynamic_status' */
1076 if (acpi_has_method(device->handle, "_STA"))
1077 device->flags.dynamic_status = 1;
1079 /* Presence of _RMV indicates 'removable' */
1080 if (acpi_has_method(device->handle, "_RMV"))
1081 device->flags.removable = 1;
1083 /* Presence of _EJD|_EJ0 indicates 'ejectable' */
1084 if (acpi_has_method(device->handle, "_EJD") ||
1085 acpi_has_method(device->handle, "_EJ0"))
1086 device->flags.ejectable = 1;
1089 static void acpi_device_get_busid(struct acpi_device *device)
1091 char bus_id[5] = { '?', 0 };
1092 struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1098 * The device's Bus ID is simply the object name.
1099 * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1101 if (ACPI_IS_ROOT_DEVICE(device)) {
1102 strcpy(device->pnp.bus_id, "ACPI");
1106 switch (device->device_type) {
1107 case ACPI_BUS_TYPE_POWER_BUTTON:
1108 strcpy(device->pnp.bus_id, "PWRF");
1110 case ACPI_BUS_TYPE_SLEEP_BUTTON:
1111 strcpy(device->pnp.bus_id, "SLPF");
1113 case ACPI_BUS_TYPE_ECDT_EC:
1114 strcpy(device->pnp.bus_id, "ECDT");
1117 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1118 /* Clean up trailing underscores (if any) */
1119 for (i = 3; i > 1; i--) {
1120 if (bus_id[i] == '_')
1125 strcpy(device->pnp.bus_id, bus_id);
1131 * acpi_ata_match - see if an acpi object is an ATA device
1133 * If an acpi object has one of the ACPI ATA methods defined,
1134 * then we can safely call it an ATA device.
1136 bool acpi_ata_match(acpi_handle handle)
1138 return acpi_has_method(handle, "_GTF") ||
1139 acpi_has_method(handle, "_GTM") ||
1140 acpi_has_method(handle, "_STM") ||
1141 acpi_has_method(handle, "_SDD");
1145 * acpi_bay_match - see if an acpi object is an ejectable driver bay
1147 * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1148 * then we can safely call it an ejectable drive bay
1150 bool acpi_bay_match(acpi_handle handle)
1152 acpi_handle phandle;
1154 if (!acpi_has_method(handle, "_EJ0"))
1156 if (acpi_ata_match(handle))
1158 if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1161 return acpi_ata_match(phandle);
1164 bool acpi_device_is_battery(struct acpi_device *adev)
1166 struct acpi_hardware_id *hwid;
1168 list_for_each_entry(hwid, &adev->pnp.ids, list)
1169 if (!strcmp("PNP0C0A", hwid->id))
1175 static bool is_ejectable_bay(struct acpi_device *adev)
1177 acpi_handle handle = adev->handle;
1179 if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
1182 return acpi_bay_match(handle);
1186 * acpi_dock_match - see if an acpi object has a _DCK method
1188 bool acpi_dock_match(acpi_handle handle)
1190 return acpi_has_method(handle, "_DCK");
1194 acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
1195 void **return_value)
1197 long *cap = context;
1199 if (acpi_has_method(handle, "_BCM") &&
1200 acpi_has_method(handle, "_BCL")) {
1201 acpi_handle_debug(handle, "Found generic backlight support\n");
1202 *cap |= ACPI_VIDEO_BACKLIGHT;
1203 /* We have backlight support, no need to scan further */
1204 return AE_CTRL_TERMINATE;
1209 /* Returns true if the ACPI object is a video device which can be
1210 * handled by video.ko.
1211 * The device will get a Linux specific CID added in scan.c to
1212 * identify the device as an ACPI graphics device
1213 * Be aware that the graphics device may not be physically present
1214 * Use acpi_video_get_capabilities() to detect general ACPI video
1215 * capabilities of present cards
1217 long acpi_is_video_device(acpi_handle handle)
1219 long video_caps = 0;
1221 /* Is this device able to support video switching ? */
1222 if (acpi_has_method(handle, "_DOD") || acpi_has_method(handle, "_DOS"))
1223 video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
1225 /* Is this device able to retrieve a video ROM ? */
1226 if (acpi_has_method(handle, "_ROM"))
1227 video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
1229 /* Is this device able to configure which video head to be POSTed ? */
1230 if (acpi_has_method(handle, "_VPO") &&
1231 acpi_has_method(handle, "_GPD") &&
1232 acpi_has_method(handle, "_SPD"))
1233 video_caps |= ACPI_VIDEO_DEVICE_POSTING;
1235 /* Only check for backlight functionality if one of the above hit. */
1237 acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
1238 ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
1243 EXPORT_SYMBOL(acpi_is_video_device);
1245 const char *acpi_device_hid(struct acpi_device *device)
1247 struct acpi_hardware_id *hid;
1249 if (list_empty(&device->pnp.ids))
1252 hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1255 EXPORT_SYMBOL(acpi_device_hid);
1257 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1259 struct acpi_hardware_id *id;
1261 id = kmalloc(sizeof(*id), GFP_KERNEL);
1265 id->id = kstrdup_const(dev_id, GFP_KERNEL);
1271 list_add_tail(&id->list, &pnp->ids);
1272 pnp->type.hardware_id = 1;
1276 * Old IBM workstations have a DSDT bug wherein the SMBus object
1277 * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1278 * prefix. Work around this.
1280 static bool acpi_ibm_smbus_match(acpi_handle handle)
1282 char node_name[ACPI_PATH_SEGMENT_LENGTH];
1283 struct acpi_buffer path = { sizeof(node_name), node_name };
1285 if (!dmi_name_in_vendors("IBM"))
1288 /* Look for SMBS object */
1289 if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1290 strcmp("SMBS", path.pointer))
1293 /* Does it have the necessary (but misnamed) methods? */
1294 if (acpi_has_method(handle, "SBI") &&
1295 acpi_has_method(handle, "SBR") &&
1296 acpi_has_method(handle, "SBW"))
1302 static bool acpi_object_is_system_bus(acpi_handle handle)
1306 if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
1309 if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
1316 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1319 struct acpi_device_info *info = NULL;
1320 struct acpi_pnp_device_id_list *cid_list;
1323 switch (device_type) {
1324 case ACPI_BUS_TYPE_DEVICE:
1325 if (handle == ACPI_ROOT_OBJECT) {
1326 acpi_add_id(pnp, ACPI_SYSTEM_HID);
1330 acpi_get_object_info(handle, &info);
1332 pr_err("%s: Error reading device info\n", __func__);
1336 if (info->valid & ACPI_VALID_HID) {
1337 acpi_add_id(pnp, info->hardware_id.string);
1338 pnp->type.platform_id = 1;
1340 if (info->valid & ACPI_VALID_CID) {
1341 cid_list = &info->compatible_id_list;
1342 for (i = 0; i < cid_list->count; i++)
1343 acpi_add_id(pnp, cid_list->ids[i].string);
1345 if (info->valid & ACPI_VALID_ADR) {
1346 pnp->bus_address = info->address;
1347 pnp->type.bus_address = 1;
1349 if (info->valid & ACPI_VALID_UID)
1350 pnp->unique_id = kstrdup(info->unique_id.string,
1352 if (info->valid & ACPI_VALID_CLS)
1353 acpi_add_id(pnp, info->class_code.string);
1358 * Some devices don't reliably have _HIDs & _CIDs, so add
1359 * synthetic HIDs to make sure drivers can find them.
1361 if (acpi_is_video_device(handle))
1362 acpi_add_id(pnp, ACPI_VIDEO_HID);
1363 else if (acpi_bay_match(handle))
1364 acpi_add_id(pnp, ACPI_BAY_HID);
1365 else if (acpi_dock_match(handle))
1366 acpi_add_id(pnp, ACPI_DOCK_HID);
1367 else if (acpi_ibm_smbus_match(handle))
1368 acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1369 else if (list_empty(&pnp->ids) &&
1370 acpi_object_is_system_bus(handle)) {
1371 /* \_SB, \_TZ, LNXSYBUS */
1372 acpi_add_id(pnp, ACPI_BUS_HID);
1373 strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1374 strcpy(pnp->device_class, ACPI_BUS_CLASS);
1378 case ACPI_BUS_TYPE_POWER:
1379 acpi_add_id(pnp, ACPI_POWER_HID);
1381 case ACPI_BUS_TYPE_PROCESSOR:
1382 acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1384 case ACPI_BUS_TYPE_THERMAL:
1385 acpi_add_id(pnp, ACPI_THERMAL_HID);
1387 case ACPI_BUS_TYPE_POWER_BUTTON:
1388 acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1390 case ACPI_BUS_TYPE_SLEEP_BUTTON:
1391 acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1393 case ACPI_BUS_TYPE_ECDT_EC:
1394 acpi_add_id(pnp, ACPI_ECDT_HID);
1399 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1401 struct acpi_hardware_id *id, *tmp;
1403 list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1404 kfree_const(id->id);
1407 kfree(pnp->unique_id);
1411 * acpi_dma_supported - Check DMA support for the specified device.
1412 * @adev: The pointer to acpi device
1414 * Return false if DMA is not supported. Otherwise, return true
1416 bool acpi_dma_supported(const struct acpi_device *adev)
1421 if (adev->flags.cca_seen)
1425 * Per ACPI 6.0 sec 6.2.17, assume devices can do cache-coherent
1426 * DMA on "Intel platforms". Presumably that includes all x86 and
1427 * ia64, and other arches will set CONFIG_ACPI_CCA_REQUIRED=y.
1429 if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1436 * acpi_get_dma_attr - Check the supported DMA attr for the specified device.
1437 * @adev: The pointer to acpi device
1439 * Return enum dev_dma_attr.
1441 enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
1443 if (!acpi_dma_supported(adev))
1444 return DEV_DMA_NOT_SUPPORTED;
1446 if (adev->flags.coherent_dma)
1447 return DEV_DMA_COHERENT;
1449 return DEV_DMA_NON_COHERENT;
1453 * acpi_dma_get_range() - Get device DMA parameters.
1455 * @dev: device to configure
1456 * @dma_addr: pointer device DMA address result
1457 * @offset: pointer to the DMA offset result
1458 * @size: pointer to DMA range size result
1460 * Evaluate DMA regions and return respectively DMA region start, offset
1461 * and size in dma_addr, offset and size on parsing success; it does not
1462 * update the passed in values on failure.
1464 * Return 0 on success, < 0 on failure.
1466 int acpi_dma_get_range(struct device *dev, u64 *dma_addr, u64 *offset,
1469 struct acpi_device *adev;
1471 struct resource_entry *rentry;
1473 struct device *dma_dev = dev;
1474 u64 len, dma_start = U64_MAX, dma_end = 0, dma_offset = 0;
1477 * Walk the device tree chasing an ACPI companion with a _DMA
1478 * object while we go. Stop if we find a device with an ACPI
1479 * companion containing a _DMA method.
1482 adev = ACPI_COMPANION(dma_dev);
1483 if (adev && acpi_has_method(adev->handle, METHOD_NAME__DMA))
1486 dma_dev = dma_dev->parent;
1492 if (!acpi_has_method(adev->handle, METHOD_NAME__CRS)) {
1493 acpi_handle_warn(adev->handle, "_DMA is valid only if _CRS is present\n");
1497 ret = acpi_dev_get_dma_resources(adev, &list);
1499 list_for_each_entry(rentry, &list, node) {
1500 if (dma_offset && rentry->offset != dma_offset) {
1502 dev_warn(dma_dev, "Can't handle multiple windows with different offsets\n");
1505 dma_offset = rentry->offset;
1507 /* Take lower and upper limits */
1508 if (rentry->res->start < dma_start)
1509 dma_start = rentry->res->start;
1510 if (rentry->res->end > dma_end)
1511 dma_end = rentry->res->end;
1514 if (dma_start >= dma_end) {
1516 dev_dbg(dma_dev, "Invalid DMA regions configuration\n");
1520 *dma_addr = dma_start - dma_offset;
1521 len = dma_end - dma_start;
1522 *size = max(len, len + 1);
1523 *offset = dma_offset;
1526 acpi_dev_free_resource_list(&list);
1528 return ret >= 0 ? 0 : ret;
1531 #ifdef CONFIG_IOMMU_API
1532 int acpi_iommu_fwspec_init(struct device *dev, u32 id,
1533 struct fwnode_handle *fwnode,
1534 const struct iommu_ops *ops)
1536 int ret = iommu_fwspec_init(dev, fwnode, ops);
1539 ret = iommu_fwspec_add_ids(dev, &id, 1);
1544 static inline const struct iommu_ops *acpi_iommu_fwspec_ops(struct device *dev)
1546 struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
1548 return fwspec ? fwspec->ops : NULL;
1551 static const struct iommu_ops *acpi_iommu_configure_id(struct device *dev,
1555 const struct iommu_ops *ops;
1558 * If we already translated the fwspec there is nothing left to do,
1559 * return the iommu_ops.
1561 ops = acpi_iommu_fwspec_ops(dev);
1565 err = iort_iommu_configure_id(dev, id_in);
1566 if (err && err != -EPROBE_DEFER)
1567 err = viot_iommu_configure(dev);
1570 * If we have reason to believe the IOMMU driver missed the initial
1571 * iommu_probe_device() call for dev, replay it to get things in order.
1573 if (!err && dev->bus && !device_iommu_mapped(dev))
1574 err = iommu_probe_device(dev);
1576 /* Ignore all other errors apart from EPROBE_DEFER */
1577 if (err == -EPROBE_DEFER) {
1578 return ERR_PTR(err);
1580 dev_dbg(dev, "Adding to IOMMU failed: %d\n", err);
1583 return acpi_iommu_fwspec_ops(dev);
1586 #else /* !CONFIG_IOMMU_API */
1588 int acpi_iommu_fwspec_init(struct device *dev, u32 id,
1589 struct fwnode_handle *fwnode,
1590 const struct iommu_ops *ops)
1595 static const struct iommu_ops *acpi_iommu_configure_id(struct device *dev,
1601 #endif /* !CONFIG_IOMMU_API */
1604 * acpi_dma_configure_id - Set-up DMA configuration for the device.
1605 * @dev: The pointer to the device
1606 * @attr: device dma attributes
1607 * @input_id: input device id const value pointer
1609 int acpi_dma_configure_id(struct device *dev, enum dev_dma_attr attr,
1610 const u32 *input_id)
1612 const struct iommu_ops *iommu;
1613 u64 dma_addr = 0, size = 0;
1615 if (attr == DEV_DMA_NOT_SUPPORTED) {
1616 set_dma_ops(dev, &dma_dummy_ops);
1620 acpi_arch_dma_setup(dev, &dma_addr, &size);
1622 iommu = acpi_iommu_configure_id(dev, input_id);
1623 if (PTR_ERR(iommu) == -EPROBE_DEFER)
1624 return -EPROBE_DEFER;
1626 arch_setup_dma_ops(dev, dma_addr, size,
1627 iommu, attr == DEV_DMA_COHERENT);
1631 EXPORT_SYMBOL_GPL(acpi_dma_configure_id);
1633 static void acpi_init_coherency(struct acpi_device *adev)
1635 unsigned long long cca = 0;
1637 struct acpi_device *parent = adev->parent;
1639 if (parent && parent->flags.cca_seen) {
1641 * From ACPI spec, OSPM will ignore _CCA if an ancestor
1644 adev->flags.cca_seen = 1;
1645 cca = parent->flags.coherent_dma;
1647 status = acpi_evaluate_integer(adev->handle, "_CCA",
1649 if (ACPI_SUCCESS(status))
1650 adev->flags.cca_seen = 1;
1651 else if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1653 * If architecture does not specify that _CCA is
1654 * required for DMA-able devices (e.g. x86),
1655 * we default to _CCA=1.
1659 acpi_handle_debug(adev->handle,
1660 "ACPI device is missing _CCA.\n");
1663 adev->flags.coherent_dma = cca;
1666 static int acpi_check_serial_bus_slave(struct acpi_resource *ares, void *data)
1668 bool *is_serial_bus_slave_p = data;
1670 if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
1673 *is_serial_bus_slave_p = true;
1675 /* no need to do more checking */
1679 static bool acpi_is_indirect_io_slave(struct acpi_device *device)
1681 struct acpi_device *parent = device->parent;
1682 static const struct acpi_device_id indirect_io_hosts[] = {
1687 return parent && !acpi_match_device_ids(parent, indirect_io_hosts);
1690 static bool acpi_device_enumeration_by_parent(struct acpi_device *device)
1692 struct list_head resource_list;
1693 bool is_serial_bus_slave = false;
1695 * These devices have multiple I2cSerialBus resources and an i2c-client
1696 * must be instantiated for each, each with its own i2c_device_id.
1697 * Normally we only instantiate an i2c-client for the first resource,
1698 * using the ACPI HID as id. These special cases are handled by the
1699 * drivers/platform/x86/i2c-multi-instantiate.c driver, which knows
1700 * which i2c_device_id to use for each resource.
1702 static const struct acpi_device_id i2c_multi_instantiate_ids[] = {
1710 if (acpi_is_indirect_io_slave(device))
1713 /* Macs use device properties in lieu of _CRS resources */
1714 if (x86_apple_machine &&
1715 (fwnode_property_present(&device->fwnode, "spiSclkPeriod") ||
1716 fwnode_property_present(&device->fwnode, "i2cAddress") ||
1717 fwnode_property_present(&device->fwnode, "baud")))
1720 /* Instantiate a pdev for the i2c-multi-instantiate drv to bind to */
1721 if (!acpi_match_device_ids(device, i2c_multi_instantiate_ids))
1724 INIT_LIST_HEAD(&resource_list);
1725 acpi_dev_get_resources(device, &resource_list,
1726 acpi_check_serial_bus_slave,
1727 &is_serial_bus_slave);
1728 acpi_dev_free_resource_list(&resource_list);
1730 return is_serial_bus_slave;
1733 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1736 INIT_LIST_HEAD(&device->pnp.ids);
1737 device->device_type = type;
1738 device->handle = handle;
1739 device->parent = acpi_bus_get_parent(handle);
1740 fwnode_init(&device->fwnode, &acpi_device_fwnode_ops);
1741 acpi_set_device_status(device, ACPI_STA_DEFAULT);
1742 acpi_device_get_busid(device);
1743 acpi_set_pnp_ids(handle, &device->pnp, type);
1744 acpi_init_properties(device);
1745 acpi_bus_get_flags(device);
1746 device->flags.match_driver = false;
1747 device->flags.initialized = true;
1748 device->flags.enumeration_by_parent =
1749 acpi_device_enumeration_by_parent(device);
1750 acpi_device_clear_enumerated(device);
1751 device_initialize(&device->dev);
1752 dev_set_uevent_suppress(&device->dev, true);
1753 acpi_init_coherency(device);
1756 static void acpi_scan_dep_init(struct acpi_device *adev)
1758 struct acpi_dep_data *dep;
1760 list_for_each_entry(dep, &acpi_dep_list, node) {
1761 if (dep->consumer == adev->handle)
1766 void acpi_device_add_finalize(struct acpi_device *device)
1768 dev_set_uevent_suppress(&device->dev, false);
1769 kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1772 static void acpi_scan_init_status(struct acpi_device *adev)
1774 if (acpi_bus_get_status(adev))
1775 acpi_set_device_status(adev, 0);
1778 static int acpi_add_single_object(struct acpi_device **child,
1779 acpi_handle handle, int type, bool dep_init)
1781 struct acpi_device *device;
1782 bool release_dep_lock = false;
1785 device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1789 acpi_init_device_object(device, handle, type);
1791 * Getting the status is delayed till here so that we can call
1792 * acpi_bus_get_status() and use its quirk handling. Note that
1793 * this must be done before the get power-/wakeup_dev-flags calls.
1795 if (type == ACPI_BUS_TYPE_DEVICE || type == ACPI_BUS_TYPE_PROCESSOR) {
1797 mutex_lock(&acpi_dep_list_lock);
1799 * Hold the lock until the acpi_tie_acpi_dev() call
1800 * below to prevent concurrent acpi_scan_clear_dep()
1801 * from deleting a dependency list entry without
1802 * updating dep_unmet for the device.
1804 release_dep_lock = true;
1805 acpi_scan_dep_init(device);
1807 acpi_scan_init_status(device);
1810 acpi_bus_get_power_flags(device);
1811 acpi_bus_get_wakeup_device_flags(device);
1813 result = acpi_tie_acpi_dev(device);
1815 if (release_dep_lock)
1816 mutex_unlock(&acpi_dep_list_lock);
1819 result = __acpi_device_add(device, acpi_device_release);
1822 acpi_device_release(&device->dev);
1826 acpi_power_add_remove_device(device, true);
1827 acpi_device_add_finalize(device);
1829 acpi_handle_debug(handle, "Added as %s, parent %s\n",
1830 dev_name(&device->dev), device->parent ?
1831 dev_name(&device->parent->dev) : "(null)");
1837 static acpi_status acpi_get_resource_memory(struct acpi_resource *ares,
1840 struct resource *res = context;
1842 if (acpi_dev_resource_memory(ares, res))
1843 return AE_CTRL_TERMINATE;
1848 static bool acpi_device_should_be_hidden(acpi_handle handle)
1851 struct resource res;
1853 /* Check if it should ignore the UART device */
1854 if (!(spcr_uart_addr && acpi_has_method(handle, METHOD_NAME__CRS)))
1858 * The UART device described in SPCR table is assumed to have only one
1859 * memory resource present. So we only look for the first one here.
1861 status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1862 acpi_get_resource_memory, &res);
1863 if (ACPI_FAILURE(status) || res.start != spcr_uart_addr)
1866 acpi_handle_info(handle, "The UART device @%pa in SPCR table will be hidden\n",
1872 bool acpi_device_is_present(const struct acpi_device *adev)
1874 return adev->status.present || adev->status.functional;
1877 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1879 const struct acpi_device_id **matchid)
1881 const struct acpi_device_id *devid;
1884 return handler->match(idstr, matchid);
1886 for (devid = handler->ids; devid->id[0]; devid++)
1887 if (!strcmp((char *)devid->id, idstr)) {
1897 static struct acpi_scan_handler *acpi_scan_match_handler(const char *idstr,
1898 const struct acpi_device_id **matchid)
1900 struct acpi_scan_handler *handler;
1902 list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1903 if (acpi_scan_handler_matching(handler, idstr, matchid))
1909 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1911 if (!!hotplug->enabled == !!val)
1914 mutex_lock(&acpi_scan_lock);
1916 hotplug->enabled = val;
1918 mutex_unlock(&acpi_scan_lock);
1921 static void acpi_scan_init_hotplug(struct acpi_device *adev)
1923 struct acpi_hardware_id *hwid;
1925 if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
1926 acpi_dock_add(adev);
1929 list_for_each_entry(hwid, &adev->pnp.ids, list) {
1930 struct acpi_scan_handler *handler;
1932 handler = acpi_scan_match_handler(hwid->id, NULL);
1934 adev->flags.hotplug_notify = true;
1940 static u32 acpi_scan_check_dep(acpi_handle handle, bool check_dep)
1942 struct acpi_handle_list dep_devices;
1948 * Check for _HID here to avoid deferring the enumeration of:
1950 * 2. ACPI nodes describing USB ports.
1951 * Still, checking for _HID catches more then just these cases ...
1953 if (!check_dep || !acpi_has_method(handle, "_DEP") ||
1954 !acpi_has_method(handle, "_HID"))
1957 status = acpi_evaluate_reference(handle, "_DEP", NULL, &dep_devices);
1958 if (ACPI_FAILURE(status)) {
1959 acpi_handle_debug(handle, "Failed to evaluate _DEP.\n");
1963 for (count = 0, i = 0; i < dep_devices.count; i++) {
1964 struct acpi_device_info *info;
1965 struct acpi_dep_data *dep;
1968 status = acpi_get_object_info(dep_devices.handles[i], &info);
1969 if (ACPI_FAILURE(status)) {
1970 acpi_handle_debug(handle, "Error reading _DEP device info\n");
1974 skip = acpi_info_matches_ids(info, acpi_ignore_dep_ids);
1980 dep = kzalloc(sizeof(*dep), GFP_KERNEL);
1986 dep->supplier = dep_devices.handles[i];
1987 dep->consumer = handle;
1989 mutex_lock(&acpi_dep_list_lock);
1990 list_add_tail(&dep->node , &acpi_dep_list);
1991 mutex_unlock(&acpi_dep_list_lock);
1997 static bool acpi_bus_scan_second_pass;
1999 static acpi_status acpi_bus_check_add(acpi_handle handle, bool check_dep,
2000 struct acpi_device **adev_p)
2002 struct acpi_device *device = NULL;
2003 acpi_object_type acpi_type;
2006 acpi_bus_get_device(handle, &device);
2010 if (ACPI_FAILURE(acpi_get_type(handle, &acpi_type)))
2013 switch (acpi_type) {
2014 case ACPI_TYPE_DEVICE:
2015 if (acpi_device_should_be_hidden(handle))
2018 /* Bail out if there are dependencies. */
2019 if (acpi_scan_check_dep(handle, check_dep) > 0) {
2020 acpi_bus_scan_second_pass = true;
2021 return AE_CTRL_DEPTH;
2025 case ACPI_TYPE_ANY: /* for ACPI_ROOT_OBJECT */
2026 type = ACPI_BUS_TYPE_DEVICE;
2029 case ACPI_TYPE_PROCESSOR:
2030 type = ACPI_BUS_TYPE_PROCESSOR;
2033 case ACPI_TYPE_THERMAL:
2034 type = ACPI_BUS_TYPE_THERMAL;
2037 case ACPI_TYPE_POWER:
2038 acpi_add_power_resource(handle);
2045 * If check_dep is true at this point, the device has no dependencies,
2046 * or the creation of the device object would have been postponed above.
2048 acpi_add_single_object(&device, handle, type, !check_dep);
2050 return AE_CTRL_DEPTH;
2052 acpi_scan_init_hotplug(device);
2061 static acpi_status acpi_bus_check_add_1(acpi_handle handle, u32 lvl_not_used,
2062 void *not_used, void **ret_p)
2064 return acpi_bus_check_add(handle, true, (struct acpi_device **)ret_p);
2067 static acpi_status acpi_bus_check_add_2(acpi_handle handle, u32 lvl_not_used,
2068 void *not_used, void **ret_p)
2070 return acpi_bus_check_add(handle, false, (struct acpi_device **)ret_p);
2073 static void acpi_default_enumeration(struct acpi_device *device)
2076 * Do not enumerate devices with enumeration_by_parent flag set as
2077 * they will be enumerated by their respective parents.
2079 if (!device->flags.enumeration_by_parent) {
2080 acpi_create_platform_device(device, NULL);
2081 acpi_device_set_enumerated(device);
2083 blocking_notifier_call_chain(&acpi_reconfig_chain,
2084 ACPI_RECONFIG_DEVICE_ADD, device);
2088 static const struct acpi_device_id generic_device_ids[] = {
2089 {ACPI_DT_NAMESPACE_HID, },
2093 static int acpi_generic_device_attach(struct acpi_device *adev,
2094 const struct acpi_device_id *not_used)
2097 * Since ACPI_DT_NAMESPACE_HID is the only ID handled here, the test
2098 * below can be unconditional.
2100 if (adev->data.of_compatible)
2101 acpi_default_enumeration(adev);
2106 static struct acpi_scan_handler generic_device_handler = {
2107 .ids = generic_device_ids,
2108 .attach = acpi_generic_device_attach,
2111 static int acpi_scan_attach_handler(struct acpi_device *device)
2113 struct acpi_hardware_id *hwid;
2116 list_for_each_entry(hwid, &device->pnp.ids, list) {
2117 const struct acpi_device_id *devid;
2118 struct acpi_scan_handler *handler;
2120 handler = acpi_scan_match_handler(hwid->id, &devid);
2122 if (!handler->attach) {
2123 device->pnp.type.platform_id = 0;
2126 device->handler = handler;
2127 ret = handler->attach(device, devid);
2131 device->handler = NULL;
2140 static void acpi_bus_attach(struct acpi_device *device, bool first_pass)
2142 struct acpi_device *child;
2143 bool skip = !first_pass && device->flags.visited;
2150 if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
2151 register_dock_dependent_device(device, ejd);
2153 acpi_bus_get_status(device);
2154 /* Skip devices that are not present. */
2155 if (!acpi_device_is_present(device)) {
2156 device->flags.initialized = false;
2157 acpi_device_clear_enumerated(device);
2158 device->flags.power_manageable = 0;
2161 if (device->handler)
2164 if (!device->flags.initialized) {
2165 device->flags.power_manageable =
2166 device->power.states[ACPI_STATE_D0].flags.valid;
2167 if (acpi_bus_init_power(device))
2168 device->flags.power_manageable = 0;
2170 device->flags.initialized = true;
2171 } else if (device->flags.visited) {
2175 ret = acpi_scan_attach_handler(device);
2179 device->flags.match_driver = true;
2180 if (ret > 0 && !device->flags.enumeration_by_parent) {
2181 acpi_device_set_enumerated(device);
2185 ret = device_attach(&device->dev);
2189 if (device->pnp.type.platform_id || device->flags.enumeration_by_parent)
2190 acpi_default_enumeration(device);
2192 acpi_device_set_enumerated(device);
2195 list_for_each_entry(child, &device->children, node)
2196 acpi_bus_attach(child, first_pass);
2198 if (!skip && device->handler && device->handler->hotplug.notify_online)
2199 device->handler->hotplug.notify_online(device);
2202 static int acpi_dev_get_first_consumer_dev_cb(struct acpi_dep_data *dep, void *data)
2204 struct acpi_device *adev;
2206 adev = acpi_bus_get_acpi_device(dep->consumer);
2208 *(struct acpi_device **)data = adev;
2211 /* Continue parsing if the device object is not present. */
2215 struct acpi_scan_clear_dep_work {
2216 struct work_struct work;
2217 struct acpi_device *adev;
2220 static void acpi_scan_clear_dep_fn(struct work_struct *work)
2222 struct acpi_scan_clear_dep_work *cdw;
2224 cdw = container_of(work, struct acpi_scan_clear_dep_work, work);
2226 acpi_scan_lock_acquire();
2227 acpi_bus_attach(cdw->adev, true);
2228 acpi_scan_lock_release();
2230 acpi_dev_put(cdw->adev);
2234 static bool acpi_scan_clear_dep_queue(struct acpi_device *adev)
2236 struct acpi_scan_clear_dep_work *cdw;
2238 if (adev->dep_unmet)
2241 cdw = kmalloc(sizeof(*cdw), GFP_KERNEL);
2246 INIT_WORK(&cdw->work, acpi_scan_clear_dep_fn);
2248 * Since the work function may block on the lock until the entire
2249 * initial enumeration of devices is complete, put it into the unbound
2252 queue_work(system_unbound_wq, &cdw->work);
2257 static int acpi_scan_clear_dep(struct acpi_dep_data *dep, void *data)
2259 struct acpi_device *adev = acpi_bus_get_acpi_device(dep->consumer);
2263 if (!acpi_scan_clear_dep_queue(adev))
2267 list_del(&dep->node);
2274 * acpi_walk_dep_device_list - Apply a callback to every entry in acpi_dep_list
2275 * @handle: The ACPI handle of the supplier device
2276 * @callback: Pointer to the callback function to apply
2277 * @data: Pointer to some data to pass to the callback
2279 * The return value of the callback determines this function's behaviour. If 0
2280 * is returned we continue to iterate over acpi_dep_list. If a positive value
2281 * is returned then the loop is broken but this function returns 0. If a
2282 * negative value is returned by the callback then the loop is broken and that
2283 * value is returned as the final error.
2285 static int acpi_walk_dep_device_list(acpi_handle handle,
2286 int (*callback)(struct acpi_dep_data *, void *),
2289 struct acpi_dep_data *dep, *tmp;
2292 mutex_lock(&acpi_dep_list_lock);
2293 list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
2294 if (dep->supplier == handle) {
2295 ret = callback(dep, data);
2300 mutex_unlock(&acpi_dep_list_lock);
2302 return ret > 0 ? 0 : ret;
2306 * acpi_dev_clear_dependencies - Inform consumers that the device is now active
2307 * @supplier: Pointer to the supplier &struct acpi_device
2309 * Clear dependencies on the given device.
2311 void acpi_dev_clear_dependencies(struct acpi_device *supplier)
2313 acpi_walk_dep_device_list(supplier->handle, acpi_scan_clear_dep, NULL);
2315 EXPORT_SYMBOL_GPL(acpi_dev_clear_dependencies);
2318 * acpi_dev_get_first_consumer_dev - Return ACPI device dependent on @supplier
2319 * @supplier: Pointer to the dependee device
2321 * Returns the first &struct acpi_device which declares itself dependent on
2322 * @supplier via the _DEP buffer, parsed from the acpi_dep_list.
2324 * The caller is responsible for putting the reference to adev when it is no
2327 struct acpi_device *acpi_dev_get_first_consumer_dev(struct acpi_device *supplier)
2329 struct acpi_device *adev = NULL;
2331 acpi_walk_dep_device_list(supplier->handle,
2332 acpi_dev_get_first_consumer_dev_cb, &adev);
2336 EXPORT_SYMBOL_GPL(acpi_dev_get_first_consumer_dev);
2339 * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
2340 * @handle: Root of the namespace scope to scan.
2342 * Scan a given ACPI tree (probably recently hot-plugged) and create and add
2345 * If no devices were found, -ENODEV is returned, but it does not mean that
2346 * there has been a real error. There just have been no suitable ACPI objects
2347 * in the table trunk from which the kernel could create a device and add an
2348 * appropriate driver.
2350 * Must be called under acpi_scan_lock.
2352 int acpi_bus_scan(acpi_handle handle)
2354 struct acpi_device *device = NULL;
2356 acpi_bus_scan_second_pass = false;
2358 /* Pass 1: Avoid enumerating devices with missing dependencies. */
2360 if (ACPI_SUCCESS(acpi_bus_check_add(handle, true, &device)))
2361 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2362 acpi_bus_check_add_1, NULL, NULL,
2368 acpi_bus_attach(device, true);
2370 if (!acpi_bus_scan_second_pass)
2373 /* Pass 2: Enumerate all of the remaining devices. */
2377 if (ACPI_SUCCESS(acpi_bus_check_add(handle, false, &device)))
2378 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2379 acpi_bus_check_add_2, NULL, NULL,
2382 acpi_bus_attach(device, false);
2386 EXPORT_SYMBOL(acpi_bus_scan);
2389 * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
2390 * @adev: Root of the ACPI namespace scope to walk.
2392 * Must be called under acpi_scan_lock.
2394 void acpi_bus_trim(struct acpi_device *adev)
2396 struct acpi_scan_handler *handler = adev->handler;
2397 struct acpi_device *child;
2399 list_for_each_entry_reverse(child, &adev->children, node)
2400 acpi_bus_trim(child);
2402 adev->flags.match_driver = false;
2404 if (handler->detach)
2405 handler->detach(adev);
2407 adev->handler = NULL;
2409 device_release_driver(&adev->dev);
2412 * Most likely, the device is going away, so put it into D3cold before
2415 acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
2416 adev->flags.initialized = false;
2417 acpi_device_clear_enumerated(adev);
2419 EXPORT_SYMBOL_GPL(acpi_bus_trim);
2421 int acpi_bus_register_early_device(int type)
2423 struct acpi_device *device = NULL;
2426 result = acpi_add_single_object(&device, NULL, type, false);
2430 device->flags.match_driver = true;
2431 return device_attach(&device->dev);
2433 EXPORT_SYMBOL_GPL(acpi_bus_register_early_device);
2435 static int acpi_bus_scan_fixed(void)
2440 * Enumerate all fixed-feature devices.
2442 if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2443 struct acpi_device *device = NULL;
2445 result = acpi_add_single_object(&device, NULL,
2446 ACPI_BUS_TYPE_POWER_BUTTON, false);
2450 device->flags.match_driver = true;
2451 result = device_attach(&device->dev);
2455 device_init_wakeup(&device->dev, true);
2458 if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2459 struct acpi_device *device = NULL;
2461 result = acpi_add_single_object(&device, NULL,
2462 ACPI_BUS_TYPE_SLEEP_BUTTON, false);
2466 device->flags.match_driver = true;
2467 result = device_attach(&device->dev);
2470 return result < 0 ? result : 0;
2473 static void __init acpi_get_spcr_uart_addr(void)
2476 struct acpi_table_spcr *spcr_ptr;
2478 status = acpi_get_table(ACPI_SIG_SPCR, 0,
2479 (struct acpi_table_header **)&spcr_ptr);
2480 if (ACPI_FAILURE(status)) {
2481 pr_warn("STAO table present, but SPCR is missing\n");
2485 spcr_uart_addr = spcr_ptr->serial_port.address;
2486 acpi_put_table((struct acpi_table_header *)spcr_ptr);
2489 static bool acpi_scan_initialized;
2491 int __init acpi_scan_init(void)
2495 struct acpi_table_stao *stao_ptr;
2497 acpi_pci_root_init();
2498 acpi_pci_link_init();
2499 acpi_processor_init();
2500 acpi_platform_init();
2503 acpi_cmos_rtc_init();
2504 acpi_container_init();
2505 acpi_memory_hotplug_init();
2506 acpi_watchdog_init();
2508 acpi_int340x_thermal_init();
2512 acpi_scan_add_handler(&generic_device_handler);
2515 * If there is STAO table, check whether it needs to ignore the UART
2516 * device in SPCR table.
2518 status = acpi_get_table(ACPI_SIG_STAO, 0,
2519 (struct acpi_table_header **)&stao_ptr);
2520 if (ACPI_SUCCESS(status)) {
2521 if (stao_ptr->header.length > sizeof(struct acpi_table_stao))
2522 pr_info("STAO Name List not yet supported.\n");
2524 if (stao_ptr->ignore_uart)
2525 acpi_get_spcr_uart_addr();
2527 acpi_put_table((struct acpi_table_header *)stao_ptr);
2530 acpi_gpe_apply_masked_gpes();
2531 acpi_update_all_gpes();
2534 * Although we call __add_memory() that is documented to require the
2535 * device_hotplug_lock, it is not necessary here because this is an
2536 * early code when userspace or any other code path cannot trigger
2537 * hotplug/hotunplug operations.
2539 mutex_lock(&acpi_scan_lock);
2541 * Enumerate devices in the ACPI namespace.
2543 result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2547 result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2551 /* Fixed feature devices do not exist on HW-reduced platform */
2552 if (!acpi_gbl_reduced_hardware) {
2553 result = acpi_bus_scan_fixed();
2555 acpi_detach_data(acpi_root->handle,
2556 acpi_scan_drop_device);
2557 acpi_device_del(acpi_root);
2558 acpi_bus_put_acpi_device(acpi_root);
2563 acpi_turn_off_unused_power_resources();
2565 acpi_scan_initialized = true;
2568 mutex_unlock(&acpi_scan_lock);
2572 static struct acpi_probe_entry *ape;
2573 static int acpi_probe_count;
2574 static DEFINE_MUTEX(acpi_probe_mutex);
2576 static int __init acpi_match_madt(union acpi_subtable_headers *header,
2577 const unsigned long end)
2579 if (!ape->subtable_valid || ape->subtable_valid(&header->common, ape))
2580 if (!ape->probe_subtbl(header, end))
2586 int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr)
2593 mutex_lock(&acpi_probe_mutex);
2594 for (ape = ap_head; nr; ape++, nr--) {
2595 if (ACPI_COMPARE_NAMESEG(ACPI_SIG_MADT, ape->id)) {
2596 acpi_probe_count = 0;
2597 acpi_table_parse_madt(ape->type, acpi_match_madt, 0);
2598 count += acpi_probe_count;
2601 res = acpi_table_parse(ape->id, ape->probe_table);
2606 mutex_unlock(&acpi_probe_mutex);
2611 static void acpi_table_events_fn(struct work_struct *work)
2613 acpi_scan_lock_acquire();
2614 acpi_bus_scan(ACPI_ROOT_OBJECT);
2615 acpi_scan_lock_release();
2620 void acpi_scan_table_notify(void)
2622 struct work_struct *work;
2624 if (!acpi_scan_initialized)
2627 work = kmalloc(sizeof(*work), GFP_KERNEL);
2631 INIT_WORK(work, acpi_table_events_fn);
2632 schedule_work(work);
2635 int acpi_reconfig_notifier_register(struct notifier_block *nb)
2637 return blocking_notifier_chain_register(&acpi_reconfig_chain, nb);
2639 EXPORT_SYMBOL(acpi_reconfig_notifier_register);
2641 int acpi_reconfig_notifier_unregister(struct notifier_block *nb)
2643 return blocking_notifier_chain_unregister(&acpi_reconfig_chain, nb);
2645 EXPORT_SYMBOL(acpi_reconfig_notifier_unregister);