// SPDX-License-Identifier: GPL-2.0-only /* * scan.c - support for transforming the ACPI namespace into individual objects */ #define pr_fmt(fmt) "ACPI: " fmt #include <linux/module.h> #include <linux/init.h> #include <linux/slab.h> #include <linux/kernel.h> #include <linux/acpi.h> #include <linux/acpi_iort.h> #include <linux/acpi_viot.h> #include <linux/iommu.h> #include <linux/signal.h> #include <linux/kthread.h> #include <linux/dmi.h> #include <linux/dma-map-ops.h> #include <linux/platform_data/x86/apple.h> #include <linux/pgtable.h> #include <linux/crc32.h> #include <linux/dma-direct.h> #include "internal.h" #include "sleep.h" #define ACPI_BUS_CLASS "system_bus" #define ACPI_BUS_HID "LNXSYBUS" #define ACPI_BUS_DEVICE_NAME "System Bus" #define INVALID_ACPI_HANDLE ((acpi_handle)ZERO_PAGE(0)) static const char *dummy_hid = "device"; static LIST_HEAD(acpi_dep_list); static DEFINE_MUTEX(acpi_dep_list_lock); LIST_HEAD(acpi_bus_id_list); static DEFINE_MUTEX(acpi_scan_lock); static LIST_HEAD(acpi_scan_handlers_list); DEFINE_MUTEX(acpi_device_lock); LIST_HEAD(acpi_wakeup_device_list); static DEFINE_MUTEX(acpi_hp_context_lock); /* * The UART device described by the SPCR table is the only object which needs * special-casing. Everything else is covered by ACPI namespace paths in STAO * table. */ static u64 spcr_uart_addr; void acpi_scan_lock_acquire(void) { mutex_lock(&acpi_scan_lock); } EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire); void acpi_scan_lock_release(void) { mutex_unlock(&acpi_scan_lock); } EXPORT_SYMBOL_GPL(acpi_scan_lock_release); void acpi_lock_hp_context(void) { mutex_lock(&acpi_hp_context_lock); } void acpi_unlock_hp_context(void) { mutex_unlock(&acpi_hp_context_lock); } void acpi_initialize_hp_context(struct acpi_device *adev, struct acpi_hotplug_context *hp, int (*notify)(struct acpi_device *, u32), void (*uevent)(struct acpi_device *, u32)) { acpi_lock_hp_context(); hp->notify = notify; hp->uevent = uevent; acpi_set_hp_context(adev, hp); acpi_unlock_hp_context(); } EXPORT_SYMBOL_GPL(acpi_initialize_hp_context); int acpi_scan_add_handler(struct acpi_scan_handler *handler) { if (!handler) return -EINVAL; list_add_tail(&handler->list_node, &acpi_scan_handlers_list); return 0; } int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler, const char *hotplug_profile_name) { int error; error = acpi_scan_add_handler(handler); if (error) return error; acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name); return 0; } bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent) { struct acpi_device_physical_node *pn; bool offline = true; char *envp[] = { "EVENT=offline", NULL }; /* * acpi_container_offline() calls this for all of the container's * children under the container's physical_node_lock lock. */ mutex_lock_nested(&adev->physical_node_lock, SINGLE_DEPTH_NESTING); list_for_each_entry(pn, &adev->physical_node_list, node) if (device_supports_offline(pn->dev) && !pn->dev->offline) { if (uevent) kobject_uevent_env(&pn->dev->kobj, KOBJ_CHANGE, envp); offline = false; break; } mutex_unlock(&adev->physical_node_lock); return offline; } static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data, void **ret_p) { struct acpi_device *device = acpi_fetch_acpi_dev(handle); struct acpi_device_physical_node *pn; bool second_pass = (bool)data; acpi_status status = AE_OK; if (!device) return AE_OK; if (device->handler && !device->handler->hotplug.enabled) { *ret_p = &device->dev; return AE_SUPPORT; } mutex_lock(&device->physical_node_lock); list_for_each_entry(pn, &device->physical_node_list, node) { int ret; if (second_pass) { /* Skip devices offlined by the first pass. */ if (pn->put_online) continue; } else { pn->put_online = false; } ret = device_offline(pn->dev); if (ret >= 0) { pn->put_online = !ret; } else { *ret_p = pn->dev; if (second_pass) { status = AE_ERROR; break; } } } mutex_unlock(&device->physical_node_lock); return status; } static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data, void **ret_p) { struct acpi_device *device = acpi_fetch_acpi_dev(handle); struct acpi_device_physical_node *pn; if (!device) return AE_OK; mutex_lock(&device->physical_node_lock); list_for_each_entry(pn, &device->physical_node_list, node) if (pn->put_online) { device_online(pn->dev); pn->put_online = false; } mutex_unlock(&device->physical_node_lock); return AE_OK; } static int acpi_scan_try_to_offline(struct acpi_device *device) { acpi_handle handle = device->handle; struct device *errdev = NULL; acpi_status status; /* * Carry out two passes here and ignore errors in the first pass, * because if the devices in question are memory blocks and * CONFIG_MEMCG is set, one of the blocks may hold data structures * that the other blocks depend on, but it is not known in advance which * block holds them. * * If the first pass is successful, the second one isn't needed, though. */ status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX, NULL, acpi_bus_offline, (void *)false, (void **)&errdev); if (status == AE_SUPPORT) { dev_warn(errdev, "Offline disabled.\n"); acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX, acpi_bus_online, NULL, NULL, NULL); return -EPERM; } acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev); if (errdev) { errdev = NULL; acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX, NULL, acpi_bus_offline, (void *)true, (void **)&errdev); if (!errdev) acpi_bus_offline(handle, 0, (void *)true, (void **)&errdev); if (errdev) { dev_warn(errdev, "Offline failed.\n"); acpi_bus_online(handle, 0, NULL, NULL); acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX, acpi_bus_online, NULL, NULL, NULL); return -EBUSY; } } return 0; } static int acpi_scan_hot_remove(struct acpi_device *device) { acpi_handle handle = device->handle; unsigned long long sta; acpi_status status; if (device->handler && device->handler->hotplug.demand_offline) { if (!acpi_scan_is_offline(device, true)) return -EBUSY; } else { int error = acpi_scan_try_to_offline(device); if (error) return error; } acpi_handle_debug(handle, "Ejecting\n"); acpi_bus_trim(device); acpi_evaluate_lck(handle, 0); /* * TBD: _EJD support. */ status = acpi_evaluate_ej0(handle); if (status == AE_NOT_FOUND) return -ENODEV; else if (ACPI_FAILURE(status)) return -EIO; /* * Verify if eject was indeed successful. If not, log an error * message. No need to call _OST since _EJ0 call was made OK. */ status = acpi_evaluate_integer(handle, "_STA", NULL, &sta); if (ACPI_FAILURE(status)) { acpi_handle_warn(handle, "Status check after eject failed (0x%x)\n", status); } else if (sta & ACPI_STA_DEVICE_ENABLED) { acpi_handle_warn(handle, "Eject incomplete - status 0x%llx\n", sta); } return 0; } static int acpi_scan_device_not_present(struct acpi_device *adev) { if (!acpi_device_enumerated(adev)) { dev_warn(&adev->dev, "Still not present\n"); return -EALREADY; } acpi_bus_trim(adev); return 0; } static int acpi_scan_device_check(struct acpi_device *adev) { int error; acpi_bus_get_status(adev); if (adev->status.present || adev->status.functional) { /* * This function is only called for device objects for which * matching scan handlers exist. The only situation in which * the scan handler is not attached to this device object yet * is when the device has just appeared (either it wasn't * present at all before or it was removed and then added * again). */ if (adev->handler) { dev_warn(&adev->dev, "Already enumerated\n"); return -EALREADY; } error = acpi_bus_scan(adev->handle); if (error) { dev_warn(&adev->dev, "Namespace scan failure\n"); return error; } if (!adev->handler) { dev_warn(&adev->dev, "Enumeration failure\n"); error = -ENODEV; } } else { error = acpi_scan_device_not_present(adev); } return error; } static int acpi_scan_bus_check(struct acpi_device *adev, void *not_used) { struct acpi_scan_handler *handler = adev->handler; int error; acpi_bus_get_status(adev); if (!(adev->status.present || adev->status.functional)) { acpi_scan_device_not_present(adev); return 0; } if (handler && handler->hotplug.scan_dependent) return handler->hotplug.scan_dependent(adev); error = acpi_bus_scan(adev->handle); if (error) { dev_warn(&adev->dev, "Namespace scan failure\n"); return error; } return acpi_dev_for_each_child(adev, acpi_scan_bus_check, NULL); } static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type) { switch (type) { case ACPI_NOTIFY_BUS_CHECK: return acpi_scan_bus_check(adev, NULL); case ACPI_NOTIFY_DEVICE_CHECK: return acpi_scan_device_check(adev); case ACPI_NOTIFY_EJECT_REQUEST: case ACPI_OST_EC_OSPM_EJECT: if (adev->handler && !adev->handler->hotplug.enabled) { dev_info(&adev->dev, "Eject disabled\n"); return -EPERM; } acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST, ACPI_OST_SC_EJECT_IN_PROGRESS, NULL); return acpi_scan_hot_remove(adev); } return -EINVAL; } void acpi_device_hotplug(struct acpi_device *adev, u32 src) { u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE; int error = -ENODEV; lock_device_hotplug(); mutex_lock(&acpi_scan_lock); /* * The device object's ACPI handle cannot become invalid as long as we * are holding acpi_scan_lock, but it might have become invalid before * that lock was acquired. */ if (adev->handle == INVALID_ACPI_HANDLE) goto err_out; if (adev->flags.is_dock_station) { error = dock_notify(adev, src); } else if (adev->flags.hotplug_notify) { error = acpi_generic_hotplug_event(adev, src); } else { int (*notify)(struct acpi_device *, u32); acpi_lock_hp_context(); notify = adev->hp ? adev->hp->notify : NULL; acpi_unlock_hp_context(); /* * There may be additional notify handlers for device objects * without the .event() callback, so ignore them here. */ if (notify) error = notify(adev, src); else goto out; } switch (error) { case 0: ost_code = ACPI_OST_SC_SUCCESS; break; case -EPERM: ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED; break; case -EBUSY: ost_code = ACPI_OST_SC_DEVICE_BUSY; break; default: ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE; break; } err_out: acpi_evaluate_ost(adev->handle, src, ost_code, NULL); out: acpi_put_acpi_dev(adev); mutex_unlock(&acpi_scan_lock); unlock_device_hotplug(); } static void acpi_free_power_resources_lists(struct acpi_device *device) { int i; if (device->wakeup.flags.valid) acpi_power_resources_list_free(&device->wakeup.resources); if (!device->power.flags.power_resources) return; for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) { struct acpi_device_power_state *ps = &device->power.states[i]; acpi_power_resources_list_free(&ps->resources); } } static void acpi_device_release(struct device *dev) { struct acpi_device *acpi_dev = to_acpi_device(dev); acpi_free_properties(acpi_dev); acpi_free_pnp_ids(&acpi_dev->pnp); acpi_free_power_resources_lists(acpi_dev); kfree(acpi_dev); } static void acpi_device_del(struct acpi_device *device) { struct acpi_device_bus_id *acpi_device_bus_id; mutex_lock(&acpi_device_lock); list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) if (!strcmp(acpi_device_bus_id->bus_id, acpi_device_hid(device))) { ida_free(&acpi_device_bus_id->instance_ida, device->pnp.instance_no); if (ida_is_empty(&acpi_device_bus_id->instance_ida)) { list_del(&acpi_device_bus_id->node); kfree_const(acpi_device_bus_id->bus_id); kfree(acpi_device_bus_id); } break; } list_del(&device->wakeup_list); mutex_unlock(&acpi_device_lock); acpi_power_add_remove_device(device, false); acpi_device_remove_files(device); if (device->remove) device->remove(device); device_del(&device->dev); } static BLOCKING_NOTIFIER_HEAD(acpi_reconfig_chain); static LIST_HEAD(acpi_device_del_list); static DEFINE_MUTEX(acpi_device_del_lock); static void acpi_device_del_work_fn(struct work_struct *work_not_used) { for (;;) { struct acpi_device *adev; mutex_lock(&acpi_device_del_lock); if (list_empty(&acpi_device_del_list)) { mutex_unlock(&acpi_device_del_lock); break; } adev = list_first_entry(&acpi_device_del_list, struct acpi_device, del_list); list_del(&adev->del_list); mutex_unlock(&acpi_device_del_lock); blocking_notifier_call_chain(&acpi_reconfig_chain, ACPI_RECONFIG_DEVICE_REMOVE, adev); acpi_device_del(adev); /* * Drop references to all power resources that might have been * used by the device. */ acpi_power_transition(adev, ACPI_STATE_D3_COLD); acpi_dev_put(adev); } } /** * acpi_scan_drop_device - Drop an ACPI device object. * @handle: Handle of an ACPI namespace node, not used. * @context: Address of the ACPI device object to drop. * * This is invoked by acpi_ns_delete_node() during the removal of the ACPI * namespace node the device object pointed to by @context is attached to. * * The unregistration is carried out asynchronously to avoid running * acpi_device_del() under the ACPICA's namespace mutex and the list is used to * ensure the correct ordering (the device objects must be unregistered in the * same order in which the corresponding namespace nodes are deleted). */ static void acpi_scan_drop_device(acpi_handle handle, void *context) { static DECLARE_WORK(work, acpi_device_del_work_fn); struct acpi_device *adev = context; mutex_lock(&acpi_device_del_lock); /* * Use the ACPI hotplug workqueue which is ordered, so this work item * won't run after any hotplug work items submitted subsequently. That * prevents attempts to register device objects identical to those being * deleted from happening concurrently (such attempts result from * hotplug events handled via the ACPI hotplug workqueue). It also will * run after all of the work items submitted previously, which helps * those work items to ensure that they are not accessing stale device * objects. */ if (list_empty(&acpi_device_del_list)) acpi_queue_hotplug_work(&work); list_add_tail(&adev->del_list, &acpi_device_del_list); /* Make acpi_ns_validate_handle() return NULL for this handle. */ adev->handle = INVALID_ACPI_HANDLE; mutex_unlock(&acpi_device_del_lock); } static struct acpi_device *handle_to_device(acpi_handle handle, void (*callback)(void *)) { struct acpi_device *adev = NULL; acpi_status status; status = acpi_get_data_full(handle, acpi_scan_drop_device, (void **)&adev, callback); if (ACPI_FAILURE(status) || !adev) { acpi_handle_debug(handle, "No context!\n"); return NULL; } return adev; } /** * acpi_fetch_acpi_dev - Retrieve ACPI device object. * @handle: ACPI handle associated with the requested ACPI device object. * * Return a pointer to the ACPI device object associated with @handle, if * present, or NULL otherwise. */ struct acpi_device *acpi_fetch_acpi_dev(acpi_handle handle) { return handle_to_device(handle, NULL); } EXPORT_SYMBOL_GPL(acpi_fetch_acpi_dev); static void get_acpi_device(void *dev) { acpi_dev_get(dev); } /** * acpi_get_acpi_dev - Retrieve ACPI device object and reference count it. * @handle: ACPI handle associated with the requested ACPI device object. * * Return a pointer to the ACPI device object associated with @handle and bump * up that object's reference counter (under the ACPI Namespace lock), if * present, or return NULL otherwise. * * The ACPI device object reference acquired by this function needs to be * dropped via acpi_dev_put(). */ struct acpi_device *acpi_get_acpi_dev(acpi_handle handle) { return handle_to_device(handle, get_acpi_device); } EXPORT_SYMBOL_GPL(acpi_get_acpi_dev); static struct acpi_device_bus_id *acpi_device_bus_id_match(const char *dev_id) { struct acpi_device_bus_id *acpi_device_bus_id; /* Find suitable bus_id and instance number in acpi_bus_id_list. */ list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) { if (!strcmp(acpi_device_bus_id->bus_id, dev_id)) return acpi_device_bus_id; } return NULL; } static int acpi_device_set_name(struct acpi_device *device, struct acpi_device_bus_id *acpi_device_bus_id) { struct ida *instance_ida = &acpi_device_bus_id->instance_ida; int result; result = ida_alloc(instance_ida, GFP_KERNEL); if (result < 0) return result; device->pnp.instance_no = result; dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, result); return 0; } int acpi_tie_acpi_dev(struct acpi_device *adev) { acpi_handle handle = adev->handle; acpi_status status; if (!handle) return 0; status = acpi_attach_data(handle, acpi_scan_drop_device, adev); if (ACPI_FAILURE(status)) { acpi_handle_err(handle, "Unable to attach device data\n"); return -ENODEV; } return 0; } static void acpi_store_pld_crc(struct acpi_device *adev) { struct acpi_pld_info *pld; acpi_status status; status = acpi_get_physical_device_location(adev->handle, &pld); if (ACPI_FAILURE(status)) return; adev->pld_crc = crc32(~0, pld, sizeof(*pld)); ACPI_FREE(pld); } int acpi_device_add(struct acpi_device *device) { struct acpi_device_bus_id *acpi_device_bus_id; int result; /* * Linkage * ------- * Link this device to its parent and siblings. */ INIT_LIST_HEAD(&device->wakeup_list); INIT_LIST_HEAD(&device->physical_node_list); INIT_LIST_HEAD(&device->del_list); mutex_init(&device->physical_node_lock); mutex_lock(&acpi_device_lock); acpi_device_bus_id = acpi_device_bus_id_match(acpi_device_hid(device)); if (acpi_device_bus_id) { result = acpi_device_set_name(device, acpi_device_bus_id); if (result) goto err_unlock; } else { acpi_device_bus_id = kzalloc(sizeof(*acpi_device_bus_id), GFP_KERNEL); if (!acpi_device_bus_id) { result = -ENOMEM; goto err_unlock; } acpi_device_bus_id->bus_id = kstrdup_const(acpi_device_hid(device), GFP_KERNEL); if (!acpi_device_bus_id->bus_id) { kfree(acpi_device_bus_id); result = -ENOMEM; goto err_unlock; } ida_init(&acpi_device_bus_id->instance_ida); result = acpi_device_set_name(device, acpi_device_bus_id); if (result) { kfree_const(acpi_device_bus_id->bus_id); kfree(acpi_device_bus_id); goto err_unlock; } list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list); } if (device->wakeup.flags.valid) list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list); acpi_store_pld_crc(device); mutex_unlock(&acpi_device_lock); result = device_add(&device->dev); if (result) { dev_err(&device->dev, "Error registering device\n"); goto err; } result = acpi_device_setup_files(device); if (result) pr_err("Error creating sysfs interface for device %s\n", dev_name(&device->dev)); return 0; err: mutex_lock(&acpi_device_lock); list_del(&device->wakeup_list); err_unlock: mutex_unlock(&acpi_device_lock); acpi_detach_data(device->handle, acpi_scan_drop_device); return result; } /* -------------------------------------------------------------------------- Device Enumeration -------------------------------------------------------------------------- */ static bool acpi_info_matches_ids(struct acpi_device_info *info, const char * const ids[]) { struct acpi_pnp_device_id_list *cid_list = NULL; int i, index; if (!(info->valid & ACPI_VALID_HID)) return false; index = match_string(ids, -1, info->hardware_id.string); if (index >= 0) return true; if (info->valid & ACPI_VALID_CID) cid_list = &info->compatible_id_list; if (!cid_list) return false; for (i = 0; i < cid_list->count; i++) { index = match_string(ids, -1, cid_list->ids[i].string); if (index >= 0) return true; } return false; } /* List of HIDs for which we ignore matching ACPI devices, when checking _DEP lists. */ static const char * const acpi_ignore_dep_ids[] = { "PNP0D80", /* Windows-compatible System Power Management Controller */ "INT33BD", /* Intel Baytrail Mailbox Device */ "LATT2021", /* Lattice FW Update Client Driver */ NULL }; /* List of HIDs for which we honor deps of matching ACPI devs, when checking _DEP lists. */ static const char * const acpi_honor_dep_ids[] = { "INT3472", /* Camera sensor PMIC / clk and regulator info */ "INTC1059", /* IVSC (TGL) driver must be loaded to allow i2c access to camera sensors */ "INTC1095", /* IVSC (ADL) driver must be loaded to allow i2c access to camera sensors */ "INTC100A", /* IVSC (RPL) driver must be loaded to allow i2c access to camera sensors */ NULL }; static struct acpi_device *acpi_find_parent_acpi_dev(acpi_handle handle) { struct acpi_device *adev; /* * Fixed hardware devices do not appear in the namespace and do not * have handles, but we fabricate acpi_devices for them, so we have * to deal with them specially. */ if (!handle) return acpi_root; do { acpi_status status; status = acpi_get_parent(handle, &handle); if (ACPI_FAILURE(status)) { if (status != AE_NULL_ENTRY) return acpi_root; return NULL; } adev = acpi_fetch_acpi_dev(handle); } while (!adev); return adev; } acpi_status acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd) { acpi_status status; acpi_handle tmp; struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL}; union acpi_object *obj; status = acpi_get_handle(handle, "_EJD", &tmp); if (ACPI_FAILURE(status)) return status; status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer); if (ACPI_SUCCESS(status)) { obj = buffer.pointer; status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer, ejd); kfree(buffer.pointer); } return status; } EXPORT_SYMBOL_GPL(acpi_bus_get_ejd); static int acpi_bus_extract_wakeup_device_power_package(struct acpi_device *dev) { acpi_handle handle = dev->handle; struct acpi_device_wakeup *wakeup = &dev->wakeup; struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; union acpi_object *package = NULL; union acpi_object *element = NULL; acpi_status status; int err = -ENODATA; INIT_LIST_HEAD(&wakeup->resources); /* _PRW */ status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer); if (ACPI_FAILURE(status)) { acpi_handle_info(handle, "_PRW evaluation failed: %s\n", acpi_format_exception(status)); return err; } package = (union acpi_object *)buffer.pointer; if (!package || package->package.count < 2) goto out; element = &(package->package.elements[0]); if (!element) goto out; if (element->type == ACPI_TYPE_PACKAGE) { if ((element->package.count < 2) || (element->package.elements[0].type != ACPI_TYPE_LOCAL_REFERENCE) || (element->package.elements[1].type != ACPI_TYPE_INTEGER)) goto out; wakeup->gpe_device = element->package.elements[0].reference.handle; wakeup->gpe_number = (u32) element->package.elements[1].integer.value; } else if (element->type == ACPI_TYPE_INTEGER) { wakeup->gpe_device = NULL; wakeup->gpe_number = element->integer.value; } else { goto out; } element = &(package->package.elements[1]); if (element->type != ACPI_TYPE_INTEGER) goto out; wakeup->sleep_state = element->integer.value; err = acpi_extract_power_resources(package, 2, &wakeup->resources); if (err) goto out; if (!list_empty(&wakeup->resources)) { int sleep_state; err = acpi_power_wakeup_list_init(&wakeup->resources, &sleep_state); if (err) { acpi_handle_warn(handle, "Retrieving current states " "of wakeup power resources failed\n"); acpi_power_resources_list_free(&wakeup->resources); goto out; } if (sleep_state < wakeup->sleep_state) { acpi_handle_warn(handle, "Overriding _PRW sleep state " "(S%d) by S%d from power resources\n", (int)wakeup->sleep_state, sleep_state); wakeup->sleep_state = sleep_state; } } out: kfree(buffer.pointer); return err; } /* Do not use a button for S5 wakeup */ #define ACPI_AVOID_WAKE_FROM_S5 BIT(0) static bool acpi_wakeup_gpe_init(struct acpi_device *device) { static const struct acpi_device_id button_device_ids[] = { {"PNP0C0C", 0}, /* Power button */ {"PNP0C0D", ACPI_AVOID_WAKE_FROM_S5}, /* Lid */ {"PNP0C0E", ACPI_AVOID_WAKE_FROM_S5}, /* Sleep button */ {"", 0}, }; struct acpi_device_wakeup *wakeup = &device->wakeup; const struct acpi_device_id *match; acpi_status status; wakeup->flags.notifier_present = 0; /* Power button, Lid switch always enable wakeup */ match = acpi_match_acpi_device(button_device_ids, device); if (match) { if ((match->driver_data & ACPI_AVOID_WAKE_FROM_S5) && wakeup->sleep_state == ACPI_STATE_S5) wakeup->sleep_state = ACPI_STATE_S4; acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number); device_set_wakeup_capable(&device->dev, true); return true; } status = acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device, wakeup->gpe_number); return ACPI_SUCCESS(status); } static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device) { int err; /* Presence of _PRW indicates wake capable */ if (!acpi_has_method(device->handle, "_PRW")) return; err = acpi_bus_extract_wakeup_device_power_package(device); if (err) { dev_err(&device->dev, "Unable to extract wakeup power resources"); return; } device->wakeup.flags.valid = acpi_wakeup_gpe_init(device); device->wakeup.prepare_count = 0; /* * Call _PSW/_DSW object to disable its ability to wake the sleeping * system for the ACPI device with the _PRW object. * The _PSW object is deprecated in ACPI 3.0 and is replaced by _DSW. * So it is necessary to call _DSW object first. Only when it is not * present will the _PSW object used. */ err = acpi_device_sleep_wake(device, 0, 0, 0); if (err) pr_debug("error in _DSW or _PSW evaluation\n"); } static void acpi_bus_init_power_state(struct acpi_device *device, int state) { struct acpi_device_power_state *ps = &device->power.states[state]; char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' }; struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; acpi_status status; INIT_LIST_HEAD(&ps->resources); /* Evaluate "_PRx" to get referenced power resources */ status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer); if (ACPI_SUCCESS(status)) { union acpi_object *package = buffer.pointer; if (buffer.length && package && package->type == ACPI_TYPE_PACKAGE && package->package.count) acpi_extract_power_resources(package, 0, &ps->resources); ACPI_FREE(buffer.pointer); } /* Evaluate "_PSx" to see if we can do explicit sets */ pathname[2] = 'S'; if (acpi_has_method(device->handle, pathname)) ps->flags.explicit_set = 1; /* State is valid if there are means to put the device into it. */ if (!list_empty(&ps->resources) || ps->flags.explicit_set) ps->flags.valid = 1; ps->power = -1; /* Unknown - driver assigned */ ps->latency = -1; /* Unknown - driver assigned */ } static void acpi_bus_get_power_flags(struct acpi_device *device) { unsigned long long dsc = ACPI_STATE_D0; u32 i; /* Presence of _PS0|_PR0 indicates 'power manageable' */ if (!acpi_has_method(device->handle, "_PS0") && !acpi_has_method(device->handle, "_PR0")) return; device->flags.power_manageable = 1; /* * Power Management Flags */ if (acpi_has_method(device->handle, "_PSC")) device->power.flags.explicit_get = 1; if (acpi_has_method(device->handle, "_IRC")) device->power.flags.inrush_current = 1; if (acpi_has_method(device->handle, "_DSW")) device->power.flags.dsw_present = 1; acpi_evaluate_integer(device->handle, "_DSC", NULL, &dsc); device->power.state_for_enumeration = dsc; /* * Enumerate supported power management states */ for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) acpi_bus_init_power_state(device, i); INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources); /* Set the defaults for D0 and D3hot (always supported). */ device->power.states[ACPI_STATE_D0].flags.valid = 1; device->power.states[ACPI_STATE_D0].power = 100; device->power.states[ACPI_STATE_D3_HOT].flags.valid = 1; /* * Use power resources only if the D0 list of them is populated, because * some platforms may provide _PR3 only to indicate D3cold support and * in those cases the power resources list returned by it may be bogus. */ if (!list_empty(&device->power.states[ACPI_STATE_D0].resources)) { device->power.flags.power_resources = 1; /* * D3cold is supported if the D3hot list of power resources is * not empty. */ if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources)) device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1; } if (acpi_bus_init_power(device)) device->flags.power_manageable = 0; } static void acpi_bus_get_flags(struct acpi_device *device) { /* Presence of _STA indicates 'dynamic_status' */ if (acpi_has_method(device->handle, "_STA")) device->flags.dynamic_status = 1; /* Presence of _RMV indicates 'removable' */ if (acpi_has_method(device->handle, "_RMV")) device->flags.removable = 1; /* Presence of _EJD|_EJ0 indicates 'ejectable' */ if (acpi_has_method(device->handle, "_EJD") || acpi_has_method(device->handle, "_EJ0")) device->flags.ejectable = 1; } static void acpi_device_get_busid(struct acpi_device *device) { char bus_id[5] = { '?', 0 }; struct acpi_buffer buffer = { sizeof(bus_id), bus_id }; int i = 0; /* * Bus ID * ------ * The device's Bus ID is simply the object name. * TBD: Shouldn't this value be unique (within the ACPI namespace)? */ if (!acpi_dev_parent(device)) { strcpy(device->pnp.bus_id, "ACPI"); return; } switch (device->device_type) { case ACPI_BUS_TYPE_POWER_BUTTON: strcpy(device->pnp.bus_id, "PWRF"); break; case ACPI_BUS_TYPE_SLEEP_BUTTON: strcpy(device->pnp.bus_id, "SLPF"); break; case ACPI_BUS_TYPE_ECDT_EC: strcpy(device->pnp.bus_id, "ECDT"); break; default: acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer); /* Clean up trailing underscores (if any) */ for (i = 3; i > 1; i--) { if (bus_id[i] == '_') bus_id[i] = '\0'; else break; } strcpy(device->pnp.bus_id, bus_id); break; } } /* * acpi_ata_match - see if an acpi object is an ATA device * * If an acpi object has one of the ACPI ATA methods defined, * then we can safely call it an ATA device. */ bool acpi_ata_match(acpi_handle handle) { return acpi_has_method(handle, "_GTF") || acpi_has_method(handle, "_GTM") || acpi_has_method(handle, "_STM") || acpi_has_method(handle, "_SDD"); } /* * acpi_bay_match - see if an acpi object is an ejectable driver bay * * If an acpi object is ejectable and has one of the ACPI ATA methods defined, * then we can safely call it an ejectable drive bay */ bool acpi_bay_match(acpi_handle handle) { acpi_handle phandle; if (!acpi_has_method(handle, "_EJ0")) return false; if (acpi_ata_match(handle)) return true; if (ACPI_FAILURE(acpi_get_parent(handle, &phandle))) return false; return acpi_ata_match(phandle); } bool acpi_device_is_battery(struct acpi_device *adev) { struct acpi_hardware_id *hwid; list_for_each_entry(hwid, &adev->pnp.ids, list) if (!strcmp("PNP0C0A", hwid->id)) return true; return false; } static bool is_ejectable_bay(struct acpi_device *adev) { acpi_handle handle = adev->handle; if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev)) return true; return acpi_bay_match(handle); } /* * acpi_dock_match - see if an acpi object has a _DCK method */ bool acpi_dock_match(acpi_handle handle) { return acpi_has_method(handle, "_DCK"); } static acpi_status acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context, void **return_value) { long *cap = context; if (acpi_has_method(handle, "_BCM") && acpi_has_method(handle, "_BCL")) { acpi_handle_debug(handle, "Found generic backlight support\n"); *cap |= ACPI_VIDEO_BACKLIGHT; /* We have backlight support, no need to scan further */ return AE_CTRL_TERMINATE; } return 0; } /* Returns true if the ACPI object is a video device which can be * handled by video.ko. * The device will get a Linux specific CID added in scan.c to * identify the device as an ACPI graphics device * Be aware that the graphics device may not be physically present * Use acpi_video_get_capabilities() to detect general ACPI video * capabilities of present cards */ long acpi_is_video_device(acpi_handle handle) { long video_caps = 0; /* Is this device able to support video switching ? */ if (acpi_has_method(handle, "_DOD") || acpi_has_method(handle, "_DOS")) video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING; /* Is this device able to retrieve a video ROM ? */ if (acpi_has_method(handle, "_ROM")) video_caps |= ACPI_VIDEO_ROM_AVAILABLE; /* Is this device able to configure which video head to be POSTed ? */ if (acpi_has_method(handle, "_VPO") && acpi_has_method(handle, "_GPD") && acpi_has_method(handle, "_SPD")) video_caps |= ACPI_VIDEO_DEVICE_POSTING; /* Only check for backlight functionality if one of the above hit. */ if (video_caps) acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL, &video_caps, NULL); return video_caps; } EXPORT_SYMBOL(acpi_is_video_device); const char *acpi_device_hid(struct acpi_device *device) { struct acpi_hardware_id *hid; if (list_empty(&device->pnp.ids)) return dummy_hid; hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list); return hid->id; } EXPORT_SYMBOL(acpi_device_hid); static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id) { struct acpi_hardware_id *id; id = kmalloc(sizeof(*id), GFP_KERNEL); if (!id) return; id->id = kstrdup_const(dev_id, GFP_KERNEL); if (!id->id) { kfree(id); return; } list_add_tail(&id->list, &pnp->ids); pnp->type.hardware_id = 1; } /* * Old IBM workstations have a DSDT bug wherein the SMBus object * lacks the SMBUS01 HID and the methods do not have the necessary "_" * prefix. Work around this. */ static bool acpi_ibm_smbus_match(acpi_handle handle) { char node_name[ACPI_PATH_SEGMENT_LENGTH]; struct acpi_buffer path = { sizeof(node_name), node_name }; if (!dmi_name_in_vendors("IBM")) return false; /* Look for SMBS object */ if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) || strcmp("SMBS", path.pointer)) return false; /* Does it have the necessary (but misnamed) methods? */ if (acpi_has_method(handle, "SBI") && acpi_has_method(handle, "SBR") && acpi_has_method(handle, "SBW")) return true; return false; } static bool acpi_object_is_system_bus(acpi_handle handle) { acpi_handle tmp; if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) && tmp == handle) return true; if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) && tmp == handle) return true; return false; } static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp, int device_type) { struct acpi_device_info *info = NULL; struct acpi_pnp_device_id_list *cid_list; int i; switch (device_type) { case ACPI_BUS_TYPE_DEVICE: if (handle == ACPI_ROOT_OBJECT) { acpi_add_id(pnp, ACPI_SYSTEM_HID); break; } acpi_get_object_info(handle, &info); if (!info) { pr_err("%s: Error reading device info\n", __func__); return; } if (info->valid & ACPI_VALID_HID) { acpi_add_id(pnp, info->hardware_id.string); pnp->type.platform_id = 1; } if (info->valid & ACPI_VALID_CID) { cid_list = &info->compatible_id_list; for (i = 0; i < cid_list->count; i++) acpi_add_id(pnp, cid_list->ids[i].string); } if (info->valid & ACPI_VALID_ADR) { pnp->bus_address = info->address; pnp->type.bus_address = 1; } if (info->valid & ACPI_VALID_UID) pnp->unique_id = kstrdup(info->unique_id.string, GFP_KERNEL); if (info->valid & ACPI_VALID_CLS) acpi_add_id(pnp, info->class_code.string); kfree(info); /* * Some devices don't reliably have _HIDs & _CIDs, so add * synthetic HIDs to make sure drivers can find them. */ if (acpi_is_video_device(handle)) { acpi_add_id(pnp, ACPI_VIDEO_HID); pnp->type.backlight = 1; break; } if (acpi_bay_match(handle)) acpi_add_id(pnp, ACPI_BAY_HID); else if (acpi_dock_match(handle)) acpi_add_id(pnp, ACPI_DOCK_HID); else if (acpi_ibm_smbus_match(handle)) acpi_add_id(pnp, ACPI_SMBUS_IBM_HID); else if (list_empty(&pnp->ids) && acpi_object_is_system_bus(handle)) { /* \_SB, \_TZ, LNXSYBUS */ acpi_add_id(pnp, ACPI_BUS_HID); strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME); strcpy(pnp->device_class, ACPI_BUS_CLASS); } break; case ACPI_BUS_TYPE_POWER: acpi_add_id(pnp, ACPI_POWER_HID); break; case ACPI_BUS_TYPE_PROCESSOR: acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID); break; case ACPI_BUS_TYPE_THERMAL: acpi_add_id(pnp, ACPI_THERMAL_HID); break; case ACPI_BUS_TYPE_POWER_BUTTON: acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF); break; case ACPI_BUS_TYPE_SLEEP_BUTTON: acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF); break; case ACPI_BUS_TYPE_ECDT_EC: acpi_add_id(pnp, ACPI_ECDT_HID); break; } } void acpi_free_pnp_ids(struct acpi_device_pnp *pnp) { struct acpi_hardware_id *id, *tmp; list_for_each_entry_safe(id, tmp, &pnp->ids, list) { kfree_const(id->id); kfree(id); } kfree(pnp->unique_id); } /** * acpi_dma_supported - Check DMA support for the specified device. * @adev: The pointer to acpi device * * Return false if DMA is not supported. Otherwise, return true */ bool acpi_dma_supported(const struct acpi_device *adev) { if (!adev) return false; if (adev->flags.cca_seen) return true; /* * Per ACPI 6.0 sec 6.2.17, assume devices can do cache-coherent * DMA on "Intel platforms". Presumably that includes all x86 and * ia64, and other arches will set CONFIG_ACPI_CCA_REQUIRED=y. */ if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED)) return true; return false; } /** * acpi_get_dma_attr - Check the supported DMA attr for the specified device. * @adev: The pointer to acpi device * * Return enum dev_dma_attr. */ enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev) { if (!acpi_dma_supported(adev)) return DEV_DMA_NOT_SUPPORTED; if (adev->flags.coherent_dma) return DEV_DMA_COHERENT; else return DEV_DMA_NON_COHERENT; } /** * acpi_dma_get_range() - Get device DMA parameters. * * @dev: device to configure * @map: pointer to DMA ranges result * * Evaluate DMA regions and return pointer to DMA regions on * parsing success; it does not update the passed in values on failure. * * Return 0 on success, < 0 on failure. */ int acpi_dma_get_range(struct device *dev, const struct bus_dma_region **map) { struct acpi_device *adev; LIST_HEAD(list); struct resource_entry *rentry; int ret; struct device *dma_dev = dev; struct bus_dma_region *r; /* * Walk the device tree chasing an ACPI companion with a _DMA * object while we go. Stop if we find a device with an ACPI * companion containing a _DMA method. */ do { adev = ACPI_COMPANION(dma_dev); if (adev && acpi_has_method(adev->handle, METHOD_NAME__DMA)) break; dma_dev = dma_dev->parent; } while (dma_dev); if (!dma_dev) return -ENODEV; if (!acpi_has_method(adev->handle, METHOD_NAME__CRS)) { acpi_handle_warn(adev->handle, "_DMA is valid only if _CRS is present\n"); return -EINVAL; } ret = acpi_dev_get_dma_resources(adev, &list); if (ret > 0) { r = kcalloc(ret + 1, sizeof(*r), GFP_KERNEL); if (!r) { ret = -ENOMEM; goto out; } *map = r; list_for_each_entry(rentry, &list, node) { if (rentry->res->start >= rentry->res->end) { kfree(*map); *map = NULL; ret = -EINVAL; dev_dbg(dma_dev, "Invalid DMA regions configuration\n"); goto out; } r->cpu_start = rentry->res->start; r->dma_start = rentry->res->start - rentry->offset; r->size = resource_size(rentry->res); r->offset = rentry->offset; r++; } } out: acpi_dev_free_resource_list(&list); return ret >= 0 ? 0 : ret; } #ifdef CONFIG_IOMMU_API int acpi_iommu_fwspec_init(struct device *dev, u32 id, struct fwnode_handle *fwnode, const struct iommu_ops *ops) { int ret = iommu_fwspec_init(dev, fwnode, ops); if (!ret) ret = iommu_fwspec_add_ids(dev, &id, 1); return ret; } static inline const struct iommu_ops *acpi_iommu_fwspec_ops(struct device *dev) { struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); return fwspec ? fwspec->ops : NULL; } static const struct iommu_ops *acpi_iommu_configure_id(struct device *dev, const u32 *id_in) { int err; const struct iommu_ops *ops; /* * If we already translated the fwspec there is nothing left to do, * return the iommu_ops. */ ops = acpi_iommu_fwspec_ops(dev); if (ops) return ops; err = iort_iommu_configure_id(dev, id_in); if (err && err != -EPROBE_DEFER) err = viot_iommu_configure(dev); /* * If we have reason to believe the IOMMU driver missed the initial * iommu_probe_device() call for dev, replay it to get things in order. */ if (!err && dev->bus) err = iommu_probe_device(dev); /* Ignore all other errors apart from EPROBE_DEFER */ if (err == -EPROBE_DEFER) { return ERR_PTR(err); } else if (err) { dev_dbg(dev, "Adding to IOMMU failed: %d\n", err); return NULL; } return acpi_iommu_fwspec_ops(dev); } #else /* !CONFIG_IOMMU_API */ int acpi_iommu_fwspec_init(struct device *dev, u32 id, struct fwnode_handle *fwnode, const struct iommu_ops *ops) { return -ENODEV; } static const struct iommu_ops *acpi_iommu_configure_id(struct device *dev, const u32 *id_in) { return NULL; } #endif /* !CONFIG_IOMMU_API */ /** * acpi_dma_configure_id - Set-up DMA configuration for the device. * @dev: The pointer to the device * @attr: device dma attributes * @input_id: input device id const value pointer */ int acpi_dma_configure_id(struct device *dev, enum dev_dma_attr attr, const u32 *input_id) { const struct iommu_ops *iommu; if (attr == DEV_DMA_NOT_SUPPORTED) { set_dma_ops(dev, &dma_dummy_ops); return 0; } acpi_arch_dma_setup(dev); iommu = acpi_iommu_configure_id(dev, input_id); if (PTR_ERR(iommu) == -EPROBE_DEFER) return -EPROBE_DEFER; arch_setup_dma_ops(dev, 0, U64_MAX, iommu, attr == DEV_DMA_COHERENT); return 0; } EXPORT_SYMBOL_GPL(acpi_dma_configure_id); static void acpi_init_coherency(struct acpi_device *adev) { unsigned long long cca = 0; acpi_status status; struct acpi_device *parent = acpi_dev_parent(adev); if (parent && parent->flags.cca_seen) { /* * From ACPI spec, OSPM will ignore _CCA if an ancestor * already saw one. */ adev->flags.cca_seen = 1; cca = parent->flags.coherent_dma; } else { status = acpi_evaluate_integer(adev->handle, "_CCA", NULL, &cca); if (ACPI_SUCCESS(status)) adev->flags.cca_seen = 1; else if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED)) /* * If architecture does not specify that _CCA is * required for DMA-able devices (e.g. x86), * we default to _CCA=1. */ cca = 1; else acpi_handle_debug(adev->handle, "ACPI device is missing _CCA.\n"); } adev->flags.coherent_dma = cca; } static int acpi_check_serial_bus_slave(struct acpi_resource *ares, void *data) { bool *is_serial_bus_slave_p = data; if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) return 1; *is_serial_bus_slave_p = true; /* no need to do more checking */ return -1; } static bool acpi_is_indirect_io_slave(struct acpi_device *device) { struct acpi_device *parent = acpi_dev_parent(device); static const struct acpi_device_id indirect_io_hosts[] = { {"HISI0191", 0}, {} }; return parent && !acpi_match_device_ids(parent, indirect_io_hosts); } static bool acpi_device_enumeration_by_parent(struct acpi_device *device) { struct list_head resource_list; bool is_serial_bus_slave = false; static const struct acpi_device_id ignore_serial_bus_ids[] = { /* * These devices have multiple SerialBus resources and a client * device must be instantiated for each of them, each with * its own device id. * Normally we only instantiate one client device for the first * resource, using the ACPI HID as id. These special cases are handled * by the drivers/platform/x86/serial-multi-instantiate.c driver, which * knows which client device id to use for each resource. */ {"BSG1160", }, {"BSG2150", }, {"CSC3551", }, {"CSC3556", }, {"INT33FE", }, {"INT3515", }, /* Non-conforming _HID for Cirrus Logic already released */ {"CLSA0100", }, {"CLSA0101", }, /* * Some ACPI devs contain SerialBus resources even though they are not * attached to a serial bus at all. */ {"MSHW0028", }, /* * HIDs of device with an UartSerialBusV2 resource for which userspace * expects a regular tty cdev to be created (instead of the in kernel * serdev) and which have a kernel driver which expects a platform_dev * such as the rfkill-gpio driver. */ {"BCM4752", }, {"LNV4752", }, {} }; if (acpi_is_indirect_io_slave(device)) return true; /* Macs use device properties in lieu of _CRS resources */ if (x86_apple_machine && (fwnode_property_present(&device->fwnode, "spiSclkPeriod") || fwnode_property_present(&device->fwnode, "i2cAddress") || fwnode_property_present(&device->fwnode, "baud"))) return true; if (!acpi_match_device_ids(device, ignore_serial_bus_ids)) return false; INIT_LIST_HEAD(&resource_list); acpi_dev_get_resources(device, &resource_list, acpi_check_serial_bus_slave, &is_serial_bus_slave); acpi_dev_free_resource_list(&resource_list); return is_serial_bus_slave; } void acpi_init_device_object(struct acpi_device *device, acpi_handle handle, int type, void (*release)(struct device *)) { struct acpi_device *parent = acpi_find_parent_acpi_dev(handle); INIT_LIST_HEAD(&device->pnp.ids); device->device_type = type; device->handle = handle; device->dev.parent = parent ? &parent->dev : NULL; device->dev.release = release; device->dev.bus = &acpi_bus_type; fwnode_init(&device->fwnode, &acpi_device_fwnode_ops); acpi_set_device_status(device, ACPI_STA_DEFAULT); acpi_device_get_busid(device); acpi_set_pnp_ids(handle, &device->pnp, type); acpi_init_properties(device); acpi_bus_get_flags(device); device->flags.match_driver = false; device->flags.initialized = true; device->flags.enumeration_by_parent = acpi_device_enumeration_by_parent(device); acpi_device_clear_enumerated(device); device_initialize(&device->dev); dev_set_uevent_suppress(&device->dev, true); acpi_init_coherency(device); } static void acpi_scan_dep_init(struct acpi_device *adev) { struct acpi_dep_data *dep; list_for_each_entry(dep, &acpi_dep_list, node) { if (dep->consumer == adev->handle) { if (dep->honor_dep) adev->flags.honor_deps = 1; adev->dep_unmet++; } } } void acpi_device_add_finalize(struct acpi_device *device) { dev_set_uevent_suppress(&device->dev, false); kobject_uevent(&device->dev.kobj, KOBJ_ADD); } static void acpi_scan_init_status(struct acpi_device *adev) { if (acpi_bus_get_status(adev)) acpi_set_device_status(adev, 0); } static int acpi_add_single_object(struct acpi_device **child, acpi_handle handle, int type, bool dep_init) { struct acpi_device *device; bool release_dep_lock = false; int result; device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL); if (!device) return -ENOMEM; acpi_init_device_object(device, handle, type, acpi_device_release); /* * Getting the status is delayed till here so that we can call * acpi_bus_get_status() and use its quirk handling. Note that * this must be done before the get power-/wakeup_dev-flags calls. */ if (type == ACPI_BUS_TYPE_DEVICE || type == ACPI_BUS_TYPE_PROCESSOR) { if (dep_init) { mutex_lock(&acpi_dep_list_lock); /* * Hold the lock until the acpi_tie_acpi_dev() call * below to prevent concurrent acpi_scan_clear_dep() * from deleting a dependency list entry without * updating dep_unmet for the device. */ release_dep_lock = true; acpi_scan_dep_init(device); } acpi_scan_init_status(device); } acpi_bus_get_power_flags(device); acpi_bus_get_wakeup_device_flags(device); result = acpi_tie_acpi_dev(device); if (release_dep_lock) mutex_unlock(&acpi_dep_list_lock); if (!result) result = acpi_device_add(device); if (result) { acpi_device_release(&device->dev); return result; } acpi_power_add_remove_device(device, true); acpi_device_add_finalize(device); acpi_handle_debug(handle, "Added as %s, parent %s\n", dev_name(&device->dev), device->dev.parent ? dev_name(device->dev.parent) : "(null)"); *child = device; return 0; } static acpi_status acpi_get_resource_memory(struct acpi_resource *ares, void *context) { struct resource *res = context; if (acpi_dev_resource_memory(ares, res)) return AE_CTRL_TERMINATE; return AE_OK; } static bool acpi_device_should_be_hidden(acpi_handle handle) { acpi_status status; struct resource res; /* Check if it should ignore the UART device */ if (!(spcr_uart_addr && acpi_has_method(handle, METHOD_NAME__CRS))) return false; /* * The UART device described in SPCR table is assumed to have only one * memory resource present. So we only look for the first one here. */ status = acpi_walk_resources(handle, METHOD_NAME__CRS, acpi_get_resource_memory, &res); if (ACPI_FAILURE(status) || res.start != spcr_uart_addr) return false; acpi_handle_info(handle, "The UART device @%pa in SPCR table will be hidden\n", &res.start); return true; } bool acpi_device_is_present(const struct acpi_device *adev) { return adev->status.present || adev->status.functional; } static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler, const char *idstr, const struct acpi_device_id **matchid) { const struct acpi_device_id *devid; if (handler->match) return handler->match(idstr, matchid); for (devid = handler->ids; devid->id[0]; devid++) if (!strcmp((char *)devid->id, idstr)) { if (matchid) *matchid = devid; return true; } return false; } static struct acpi_scan_handler *acpi_scan_match_handler(const char *idstr, const struct acpi_device_id **matchid) { struct acpi_scan_handler *handler; list_for_each_entry(handler, &acpi_scan_handlers_list, list_node) if (acpi_scan_handler_matching(handler, idstr, matchid)) return handler; return NULL; } void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val) { if (!!hotplug->enabled == !!val) return; mutex_lock(&acpi_scan_lock); hotplug->enabled = val; mutex_unlock(&acpi_scan_lock); } static void acpi_scan_init_hotplug(struct acpi_device *adev) { struct acpi_hardware_id *hwid; if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) { acpi_dock_add(adev); return; } list_for_each_entry(hwid, &adev->pnp.ids, list) { struct acpi_scan_handler *handler; handler = acpi_scan_match_handler(hwid->id, NULL); if (handler) { adev->flags.hotplug_notify = true; break; } } } static u32 acpi_scan_check_dep(acpi_handle handle, bool check_dep) { struct acpi_handle_list dep_devices; acpi_status status; u32 count; int i; /* * Check for _HID here to avoid deferring the enumeration of: * 1. PCI devices. * 2. ACPI nodes describing USB ports. * Still, checking for _HID catches more then just these cases ... */ if (!check_dep || !acpi_has_method(handle, "_DEP") || !acpi_has_method(handle, "_HID")) return 0; status = acpi_evaluate_reference(handle, "_DEP", NULL, &dep_devices); if (ACPI_FAILURE(status)) { acpi_handle_debug(handle, "Failed to evaluate _DEP.\n"); return 0; } for (count = 0, i = 0; i < dep_devices.count; i++) { struct acpi_device_info *info; struct acpi_dep_data *dep; bool skip, honor_dep; status = acpi_get_object_info(dep_devices.handles[i], &info); if (ACPI_FAILURE(status)) { acpi_handle_debug(handle, "Error reading _DEP device info\n"); continue; } skip = acpi_info_matches_ids(info, acpi_ignore_dep_ids); honor_dep = acpi_info_matches_ids(info, acpi_honor_dep_ids); kfree(info); if (skip) continue; dep = kzalloc(sizeof(*dep), GFP_KERNEL); if (!dep) continue; count++; dep->supplier = dep_devices.handles[i]; dep->consumer = handle; dep->honor_dep = honor_dep; mutex_lock(&acpi_dep_list_lock); list_add_tail(&dep->node , &acpi_dep_list); mutex_unlock(&acpi_dep_list_lock); } return count; } static acpi_status acpi_bus_check_add(acpi_handle handle, bool check_dep, struct acpi_device **adev_p) { struct acpi_device *device = acpi_fetch_acpi_dev(handle); acpi_object_type acpi_type; int type; if (device) goto out; if (ACPI_FAILURE(acpi_get_type(handle, &acpi_type))) return AE_OK; switch (acpi_type) { case ACPI_TYPE_DEVICE: if (acpi_device_should_be_hidden(handle)) return AE_OK; /* Bail out if there are dependencies. */ if (acpi_scan_check_dep(handle, check_dep) > 0) return AE_CTRL_DEPTH; fallthrough; case ACPI_TYPE_ANY: /* for ACPI_ROOT_OBJECT */ type = ACPI_BUS_TYPE_DEVICE; break; case ACPI_TYPE_PROCESSOR: type = ACPI_BUS_TYPE_PROCESSOR; break; case ACPI_TYPE_THERMAL: type = ACPI_BUS_TYPE_THERMAL; break; case ACPI_TYPE_POWER: acpi_add_power_resource(handle); fallthrough; default: return AE_OK; } /* * If check_dep is true at this point, the device has no dependencies, * or the creation of the device object would have been postponed above. */ acpi_add_single_object(&device, handle, type, !check_dep); if (!device) return AE_CTRL_DEPTH; acpi_scan_init_hotplug(device); out: if (!*adev_p) *adev_p = device; return AE_OK; } static acpi_status acpi_bus_check_add_1(acpi_handle handle, u32 lvl_not_used, void *not_used, void **ret_p) { return acpi_bus_check_add(handle, true, (struct acpi_device **)ret_p); } static acpi_status acpi_bus_check_add_2(acpi_handle handle, u32 lvl_not_used, void *not_used, void **ret_p) { return acpi_bus_check_add(handle, false, (struct acpi_device **)ret_p); } static void acpi_default_enumeration(struct acpi_device *device) { /* * Do not enumerate devices with enumeration_by_parent flag set as * they will be enumerated by their respective parents. */ if (!device->flags.enumeration_by_parent) { acpi_create_platform_device(device, NULL); acpi_device_set_enumerated(device); } else { blocking_notifier_call_chain(&acpi_reconfig_chain, ACPI_RECONFIG_DEVICE_ADD, device); } } static const struct acpi_device_id generic_device_ids[] = { {ACPI_DT_NAMESPACE_HID, }, {"", }, }; static int acpi_generic_device_attach(struct acpi_device *adev, const struct acpi_device_id *not_used) { /* * Since ACPI_DT_NAMESPACE_HID is the only ID handled here, the test * below can be unconditional. */ if (adev->data.of_compatible) acpi_default_enumeration(adev); return 1; } static struct acpi_scan_handler generic_device_handler = { .ids = generic_device_ids, .attach = acpi_generic_device_attach, }; static int acpi_scan_attach_handler(struct acpi_device *device) { struct acpi_hardware_id *hwid; int ret = 0; list_for_each_entry(hwid, &device->pnp.ids, list) { const struct acpi_device_id *devid; struct acpi_scan_handler *handler; handler = acpi_scan_match_handler(hwid->id, &devid); if (handler) { if (!handler->attach) { device->pnp.type.platform_id = 0; continue; } device->handler = handler; ret = handler->attach(device, devid); if (ret > 0) break; device->handler = NULL; if (ret < 0) break; } } return ret; } static int acpi_bus_attach(struct acpi_device *device, void *first_pass) { bool skip = !first_pass && device->flags.visited; acpi_handle ejd; int ret; if (skip) goto ok; if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd))) register_dock_dependent_device(device, ejd); acpi_bus_get_status(device); /* Skip devices that are not ready for enumeration (e.g. not present) */ if (!acpi_dev_ready_for_enumeration(device)) { device->flags.initialized = false; acpi_device_clear_enumerated(device); device->flags.power_manageable = 0; return 0; } if (device->handler) goto ok; if (!device->flags.initialized) { device->flags.power_manageable = device->power.states[ACPI_STATE_D0].flags.valid; if (acpi_bus_init_power(device)) device->flags.power_manageable = 0; device->flags.initialized = true; } else if (device->flags.visited) { goto ok; } ret = acpi_scan_attach_handler(device); if (ret < 0) return 0; device->flags.match_driver = true; if (ret > 0 && !device->flags.enumeration_by_parent) { acpi_device_set_enumerated(device); goto ok; } ret = device_attach(&device->dev); if (ret < 0) return 0; if (device->pnp.type.platform_id || device->flags.enumeration_by_parent) acpi_default_enumeration(device); else acpi_device_set_enumerated(device); ok: acpi_dev_for_each_child(device, acpi_bus_attach, first_pass); if (!skip && device->handler && device->handler->hotplug.notify_online) device->handler->hotplug.notify_online(device); return 0; } static int acpi_dev_get_next_consumer_dev_cb(struct acpi_dep_data *dep, void *data) { struct acpi_device **adev_p = data; struct acpi_device *adev = *adev_p; /* * If we're passed a 'previous' consumer device then we need to skip * any consumers until we meet the previous one, and then NULL @data * so the next one can be returned. */ if (adev) { if (dep->consumer == adev->handle) *adev_p = NULL; return 0; } adev = acpi_get_acpi_dev(dep->consumer); if (adev) { *(struct acpi_device **)data = adev; return 1; } /* Continue parsing if the device object is not present. */ return 0; } struct acpi_scan_clear_dep_work { struct work_struct work; struct acpi_device *adev; }; static void acpi_scan_clear_dep_fn(struct work_struct *work) { struct acpi_scan_clear_dep_work *cdw; cdw = container_of(work, struct acpi_scan_clear_dep_work, work); acpi_scan_lock_acquire(); acpi_bus_attach(cdw->adev, (void *)true); acpi_scan_lock_release(); acpi_dev_put(cdw->adev); kfree(cdw); } static bool acpi_scan_clear_dep_queue(struct acpi_device *adev) { struct acpi_scan_clear_dep_work *cdw; if (adev->dep_unmet) return false; cdw = kmalloc(sizeof(*cdw), GFP_KERNEL); if (!cdw) return false; cdw->adev = adev; INIT_WORK(&cdw->work, acpi_scan_clear_dep_fn); /* * Since the work function may block on the lock until the entire * initial enumeration of devices is complete, put it into the unbound * workqueue. */ queue_work(system_unbound_wq, &cdw->work); return true; } static void acpi_scan_delete_dep_data(struct acpi_dep_data *dep) { list_del(&dep->node); kfree(dep); } static int acpi_scan_clear_dep(struct acpi_dep_data *dep, void *data) { struct acpi_device *adev = acpi_get_acpi_dev(dep->consumer); if (adev) { adev->dep_unmet--; if (!acpi_scan_clear_dep_queue(adev)) acpi_dev_put(adev); } if (dep->free_when_met) acpi_scan_delete_dep_data(dep); else dep->met = true; return 0; } /** * acpi_walk_dep_device_list - Apply a callback to every entry in acpi_dep_list * @handle: The ACPI handle of the supplier device * @callback: Pointer to the callback function to apply * @data: Pointer to some data to pass to the callback * * The return value of the callback determines this function's behaviour. If 0 * is returned we continue to iterate over acpi_dep_list. If a positive value * is returned then the loop is broken but this function returns 0. If a * negative value is returned by the callback then the loop is broken and that * value is returned as the final error. */ static int acpi_walk_dep_device_list(acpi_handle handle, int (*callback)(struct acpi_dep_data *, void *), void *data) { struct acpi_dep_data *dep, *tmp; int ret = 0; mutex_lock(&acpi_dep_list_lock); list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) { if (dep->supplier == handle) { ret = callback(dep, data); if (ret) break; } } mutex_unlock(&acpi_dep_list_lock); return ret > 0 ? 0 : ret; } /** * acpi_dev_clear_dependencies - Inform consumers that the device is now active * @supplier: Pointer to the supplier &struct acpi_device * * Clear dependencies on the given device. */ void acpi_dev_clear_dependencies(struct acpi_device *supplier) { acpi_walk_dep_device_list(supplier->handle, acpi_scan_clear_dep, NULL); } EXPORT_SYMBOL_GPL(acpi_dev_clear_dependencies); /** * acpi_dev_ready_for_enumeration - Check if the ACPI device is ready for enumeration * @device: Pointer to the &struct acpi_device to check * * Check if the device is present and has no unmet dependencies. * * Return true if the device is ready for enumeratino. Otherwise, return false. */ bool acpi_dev_ready_for_enumeration(const struct acpi_device *device) { if (device->flags.honor_deps && device->dep_unmet) return false; return acpi_device_is_present(device); } EXPORT_SYMBOL_GPL(acpi_dev_ready_for_enumeration); /** * acpi_dev_get_next_consumer_dev - Return the next adev dependent on @supplier * @supplier: Pointer to the dependee device * @start: Pointer to the current dependent device * * Returns the next &struct acpi_device which declares itself dependent on * @supplier via the _DEP buffer, parsed from the acpi_dep_list. * * If the returned adev is not passed as @start to this function, the caller is * responsible for putting the reference to adev when it is no longer needed. */ struct acpi_device *acpi_dev_get_next_consumer_dev(struct acpi_device *supplier, struct acpi_device *start) { struct acpi_device *adev = start; acpi_walk_dep_device_list(supplier->handle, acpi_dev_get_next_consumer_dev_cb, &adev); acpi_dev_put(start); if (adev == start) return NULL; return adev; } EXPORT_SYMBOL_GPL(acpi_dev_get_next_consumer_dev); static void acpi_scan_postponed_branch(acpi_handle handle) { struct acpi_device *adev = NULL; if (ACPI_FAILURE(acpi_bus_check_add(handle, false, &adev))) return; acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX, acpi_bus_check_add_2, NULL, NULL, (void **)&adev); acpi_bus_attach(adev, NULL); } static void acpi_scan_postponed(void) { struct acpi_dep_data *dep, *tmp; mutex_lock(&acpi_dep_list_lock); list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) { acpi_handle handle = dep->consumer; /* * In case there are multiple acpi_dep_list entries with the * same consumer, skip the current entry if the consumer device * object corresponding to it is present already. */ if (!acpi_fetch_acpi_dev(handle)) { /* * Even though the lock is released here, tmp is * guaranteed to be valid, because none of the list * entries following dep is marked as "free when met" * and so they cannot be deleted. */ mutex_unlock(&acpi_dep_list_lock); acpi_scan_postponed_branch(handle); mutex_lock(&acpi_dep_list_lock); } if (dep->met) acpi_scan_delete_dep_data(dep); else dep->free_when_met = true; } mutex_unlock(&acpi_dep_list_lock); } /** * acpi_bus_scan - Add ACPI device node objects in a given namespace scope. * @handle: Root of the namespace scope to scan. * * Scan a given ACPI tree (probably recently hot-plugged) and create and add * found devices. * * If no devices were found, -ENODEV is returned, but it does not mean that * there has been a real error. There just have been no suitable ACPI objects * in the table trunk from which the kernel could create a device and add an * appropriate driver. * * Must be called under acpi_scan_lock. */ int acpi_bus_scan(acpi_handle handle) { struct acpi_device *device = NULL; /* Pass 1: Avoid enumerating devices with missing dependencies. */ if (ACPI_SUCCESS(acpi_bus_check_add(handle, true, &device))) acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX, acpi_bus_check_add_1, NULL, NULL, (void **)&device); if (!device) return -ENODEV; acpi_bus_attach(device, (void *)true); /* Pass 2: Enumerate all of the remaining devices. */ acpi_scan_postponed(); return 0; } EXPORT_SYMBOL(acpi_bus_scan); static int acpi_bus_trim_one(struct acpi_device *adev, void *not_used) { struct acpi_scan_handler *handler = adev->handler; acpi_dev_for_each_child_reverse(adev, acpi_bus_trim_one, NULL); adev->flags.match_driver = false; if (handler) { if (handler->detach) handler->detach(adev); adev->handler = NULL; } else { device_release_driver(&adev->dev); } /* * Most likely, the device is going away, so put it into D3cold before * that. */ acpi_device_set_power(adev, ACPI_STATE_D3_COLD); adev->flags.initialized = false; acpi_device_clear_enumerated(adev); return 0; } /** * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects. * @adev: Root of the ACPI namespace scope to walk. * * Must be called under acpi_scan_lock. */ void acpi_bus_trim(struct acpi_device *adev) { acpi_bus_trim_one(adev, NULL); } EXPORT_SYMBOL_GPL(acpi_bus_trim); int acpi_bus_register_early_device(int type) { struct acpi_device *device = NULL; int result; result = acpi_add_single_object(&device, NULL, type, false); if (result) return result; device->flags.match_driver = true; return device_attach(&device->dev); } EXPORT_SYMBOL_GPL(acpi_bus_register_early_device); static void acpi_bus_scan_fixed(void) { if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) { struct acpi_device *adev = NULL; acpi_add_single_object(&adev, NULL, ACPI_BUS_TYPE_POWER_BUTTON, false); if (adev) { adev->flags.match_driver = true; if (device_attach(&adev->dev) >= 0) device_init_wakeup(&adev->dev, true); else dev_dbg(&adev->dev, "No driver\n"); } } if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) { struct acpi_device *adev = NULL; acpi_add_single_object(&adev, NULL, ACPI_BUS_TYPE_SLEEP_BUTTON, false); if (adev) { adev->flags.match_driver = true; if (device_attach(&adev->dev) < 0) dev_dbg(&adev->dev, "No driver\n"); } } } static void __init acpi_get_spcr_uart_addr(void) { acpi_status status; struct acpi_table_spcr *spcr_ptr; status = acpi_get_table(ACPI_SIG_SPCR, 0, (struct acpi_table_header **)&spcr_ptr); if (ACPI_FAILURE(status)) { pr_warn("STAO table present, but SPCR is missing\n"); return; } spcr_uart_addr = spcr_ptr->serial_port.address; acpi_put_table((struct acpi_table_header *)spcr_ptr); } static bool acpi_scan_initialized; void __init acpi_scan_init(void) { acpi_status status; struct acpi_table_stao *stao_ptr; acpi_pci_root_init(); acpi_pci_link_init(); acpi_processor_init(); acpi_platform_init(); acpi_lpss_init(); acpi_apd_init(); acpi_cmos_rtc_init(); acpi_container_init(); acpi_memory_hotplug_init(); acpi_watchdog_init(); acpi_pnp_init(); acpi_int340x_thermal_init(); acpi_init_lpit(); acpi_scan_add_handler(&generic_device_handler); /* * If there is STAO table, check whether it needs to ignore the UART * device in SPCR table. */ status = acpi_get_table(ACPI_SIG_STAO, 0, (struct acpi_table_header **)&stao_ptr); if (ACPI_SUCCESS(status)) { if (stao_ptr->header.length > sizeof(struct acpi_table_stao)) pr_info("STAO Name List not yet supported.\n"); if (stao_ptr->ignore_uart) acpi_get_spcr_uart_addr(); acpi_put_table((struct acpi_table_header *)stao_ptr); } acpi_gpe_apply_masked_gpes(); acpi_update_all_gpes(); /* * Although we call __add_memory() that is documented to require the * device_hotplug_lock, it is not necessary here because this is an * early code when userspace or any other code path cannot trigger * hotplug/hotunplug operations. */ mutex_lock(&acpi_scan_lock); /* * Enumerate devices in the ACPI namespace. */ if (acpi_bus_scan(ACPI_ROOT_OBJECT)) goto unlock; acpi_root = acpi_fetch_acpi_dev(ACPI_ROOT_OBJECT); if (!acpi_root) goto unlock; /* Fixed feature devices do not exist on HW-reduced platform */ if (!acpi_gbl_reduced_hardware) acpi_bus_scan_fixed(); acpi_turn_off_unused_power_resources(); acpi_scan_initialized = true; unlock: mutex_unlock(&acpi_scan_lock); } static struct acpi_probe_entry *ape; static int acpi_probe_count; static DEFINE_MUTEX(acpi_probe_mutex); static int __init acpi_match_madt(union acpi_subtable_headers *header, const unsigned long end) { if (!ape->subtable_valid || ape->subtable_valid(&header->common, ape)) if (!ape->probe_subtbl(header, end)) acpi_probe_count++; return 0; } int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr) { int count = 0; if (acpi_disabled) return 0; mutex_lock(&acpi_probe_mutex); for (ape = ap_head; nr; ape++, nr--) { if (ACPI_COMPARE_NAMESEG(ACPI_SIG_MADT, ape->id)) { acpi_probe_count = 0; acpi_table_parse_madt(ape->type, acpi_match_madt, 0); count += acpi_probe_count; } else { int res; res = acpi_table_parse(ape->id, ape->probe_table); if (!res) count++; } } mutex_unlock(&acpi_probe_mutex); return count; } static void acpi_table_events_fn(struct work_struct *work) { acpi_scan_lock_acquire(); acpi_bus_scan(ACPI_ROOT_OBJECT); acpi_scan_lock_release(); kfree(work); } void acpi_scan_table_notify(void) { struct work_struct *work; if (!acpi_scan_initialized) return; work = kmalloc(sizeof(*work), GFP_KERNEL); if (!work) return; INIT_WORK(work, acpi_table_events_fn); schedule_work(work); } int acpi_reconfig_notifier_register(struct notifier_block *nb) { return blocking_notifier_chain_register(&acpi_reconfig_chain, nb); } EXPORT_SYMBOL(acpi_reconfig_notifier_register); int acpi_reconfig_notifier_unregister(struct notifier_block *nb) { return blocking_notifier_chain_unregister(&acpi_reconfig_chain, nb); } EXPORT_SYMBOL(acpi_reconfig_notifier_unregister);