2 * scan.c - support for transforming the ACPI namespace into individual objects
5 #include <linux/module.h>
6 #include <linux/init.h>
7 #include <linux/slab.h>
8 #include <linux/kernel.h>
9 #include <linux/acpi.h>
10 #include <linux/signal.h>
11 #include <linux/kthread.h>
12 #include <linux/dmi.h>
13 #include <linux/nls.h>
15 #include <acpi/acpi_drivers.h>
19 #define _COMPONENT ACPI_BUS_COMPONENT
20 ACPI_MODULE_NAME("scan");
21 #define STRUCT_TO_INT(s) (*((int*)&s))
22 extern struct acpi_device *acpi_root;
24 #define ACPI_BUS_CLASS "system_bus"
25 #define ACPI_BUS_HID "LNXSYBUS"
26 #define ACPI_BUS_DEVICE_NAME "System Bus"
28 #define ACPI_IS_ROOT_DEVICE(device) (!(device)->parent)
30 static const char *dummy_hid = "device";
33 * The following ACPI IDs are known to be suitable for representing as
36 static const struct acpi_device_id acpi_platform_device_ids[] = {
40 /* Haswell LPSS devices */
53 static LIST_HEAD(acpi_device_list);
54 static LIST_HEAD(acpi_bus_id_list);
55 static DEFINE_MUTEX(acpi_scan_lock);
56 DEFINE_MUTEX(acpi_device_lock);
57 LIST_HEAD(acpi_wakeup_device_list);
59 struct acpi_device_bus_id{
61 unsigned int instance_no;
62 struct list_head node;
66 * Creates hid/cid(s) string needed for modalias and uevent
67 * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
68 * char *modalias: "acpi:IBM0001:ACPI0001"
70 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
75 struct acpi_hardware_id *id;
77 if (list_empty(&acpi_dev->pnp.ids))
80 len = snprintf(modalias, size, "acpi:");
83 list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
84 count = snprintf(&modalias[len], size, "%s:", id->id);
85 if (count < 0 || count >= size)
96 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
97 struct acpi_device *acpi_dev = to_acpi_device(dev);
100 /* Device has no HID and no CID or string is >1024 */
101 len = create_modalias(acpi_dev, buf, 1024);
107 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
110 * acpi_bus_hot_remove_device: hot-remove a device and its children
111 * @context: struct acpi_eject_event pointer (freed in this func)
113 * Hot-remove a device and its children. This function frees up the
114 * memory space passed by arg context, so that the caller may call
115 * this function asynchronously through acpi_os_hotplug_execute().
117 void acpi_bus_hot_remove_device(void *context)
119 struct acpi_eject_event *ej_event = (struct acpi_eject_event *) context;
120 struct acpi_device *device = ej_event->device;
121 acpi_handle handle = device->handle;
123 struct acpi_object_list arg_list;
124 union acpi_object arg;
125 acpi_status status = AE_OK;
126 u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE; /* default */
128 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
129 "Hot-removing device %s...\n", dev_name(&device->dev)));
131 acpi_bus_trim(device);
132 /* Device node has been released. */
135 /* power off device */
136 status = acpi_evaluate_object(handle, "_PS3", NULL, NULL);
137 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
138 printk(KERN_WARNING PREFIX
139 "Power-off device failed\n");
141 if (ACPI_SUCCESS(acpi_get_handle(handle, "_LCK", &temp))) {
143 arg_list.pointer = &arg;
144 arg.type = ACPI_TYPE_INTEGER;
145 arg.integer.value = 0;
146 acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
150 arg_list.pointer = &arg;
151 arg.type = ACPI_TYPE_INTEGER;
152 arg.integer.value = 1;
157 status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
158 if (ACPI_FAILURE(status)) {
159 if (status != AE_NOT_FOUND)
160 printk(KERN_WARNING PREFIX
161 "Eject device failed\n");
169 /* Inform firmware the hot-remove operation has completed w/ error */
170 (void) acpi_evaluate_hotplug_ost(handle,
171 ej_event->event, ost_code, NULL);
175 EXPORT_SYMBOL(acpi_bus_hot_remove_device);
178 acpi_eject_store(struct device *d, struct device_attribute *attr,
179 const char *buf, size_t count)
183 acpi_object_type type = 0;
184 struct acpi_device *acpi_device = to_acpi_device(d);
185 struct acpi_eject_event *ej_event;
187 if ((!count) || (buf[0] != '1')) {
191 if (acpi_device->driver == NULL) {
196 status = acpi_get_type(acpi_device->handle, &type);
197 if (ACPI_FAILURE(status) || (!acpi_device->flags.ejectable)) {
202 ej_event = kmalloc(sizeof(*ej_event), GFP_KERNEL);
208 ej_event->device = acpi_device;
209 if (acpi_device->flags.eject_pending) {
210 /* event originated from ACPI eject notification */
211 ej_event->event = ACPI_NOTIFY_EJECT_REQUEST;
212 acpi_device->flags.eject_pending = 0;
214 /* event originated from user */
215 ej_event->event = ACPI_OST_EC_OSPM_EJECT;
216 (void) acpi_evaluate_hotplug_ost(acpi_device->handle,
217 ej_event->event, ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
220 acpi_os_hotplug_execute(acpi_bus_hot_remove_device, (void *)ej_event);
225 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
228 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
229 struct acpi_device *acpi_dev = to_acpi_device(dev);
231 return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
233 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
235 static ssize_t acpi_device_uid_show(struct device *dev,
236 struct device_attribute *attr, char *buf)
238 struct acpi_device *acpi_dev = to_acpi_device(dev);
240 return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id);
242 static DEVICE_ATTR(uid, 0444, acpi_device_uid_show, NULL);
244 static ssize_t acpi_device_adr_show(struct device *dev,
245 struct device_attribute *attr, char *buf)
247 struct acpi_device *acpi_dev = to_acpi_device(dev);
249 return sprintf(buf, "0x%08x\n",
250 (unsigned int)(acpi_dev->pnp.bus_address));
252 static DEVICE_ATTR(adr, 0444, acpi_device_adr_show, NULL);
255 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
256 struct acpi_device *acpi_dev = to_acpi_device(dev);
257 struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
260 result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
264 result = sprintf(buf, "%s\n", (char*)path.pointer);
269 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
271 /* sysfs file that shows description text from the ACPI _STR method */
272 static ssize_t description_show(struct device *dev,
273 struct device_attribute *attr,
275 struct acpi_device *acpi_dev = to_acpi_device(dev);
278 if (acpi_dev->pnp.str_obj == NULL)
282 * The _STR object contains a Unicode identifier for a device.
283 * We need to convert to utf-8 so it can be displayed.
285 result = utf16s_to_utf8s(
286 (wchar_t *)acpi_dev->pnp.str_obj->buffer.pointer,
287 acpi_dev->pnp.str_obj->buffer.length,
288 UTF16_LITTLE_ENDIAN, buf,
291 buf[result++] = '\n';
295 static DEVICE_ATTR(description, 0444, description_show, NULL);
298 acpi_device_sun_show(struct device *dev, struct device_attribute *attr,
300 struct acpi_device *acpi_dev = to_acpi_device(dev);
302 return sprintf(buf, "%lu\n", acpi_dev->pnp.sun);
304 static DEVICE_ATTR(sun, 0444, acpi_device_sun_show, NULL);
306 static int acpi_device_setup_files(struct acpi_device *dev)
308 struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
311 unsigned long long sun;
315 * Devices gotten from FADT don't have a "path" attribute
318 result = device_create_file(&dev->dev, &dev_attr_path);
323 if (!list_empty(&dev->pnp.ids)) {
324 result = device_create_file(&dev->dev, &dev_attr_hid);
328 result = device_create_file(&dev->dev, &dev_attr_modalias);
334 * If device has _STR, 'description' file is created
336 status = acpi_get_handle(dev->handle, "_STR", &temp);
337 if (ACPI_SUCCESS(status)) {
338 status = acpi_evaluate_object(dev->handle, "_STR",
340 if (ACPI_FAILURE(status))
341 buffer.pointer = NULL;
342 dev->pnp.str_obj = buffer.pointer;
343 result = device_create_file(&dev->dev, &dev_attr_description);
348 if (dev->flags.bus_address)
349 result = device_create_file(&dev->dev, &dev_attr_adr);
350 if (dev->pnp.unique_id)
351 result = device_create_file(&dev->dev, &dev_attr_uid);
353 status = acpi_evaluate_integer(dev->handle, "_SUN", NULL, &sun);
354 if (ACPI_SUCCESS(status)) {
355 dev->pnp.sun = (unsigned long)sun;
356 result = device_create_file(&dev->dev, &dev_attr_sun);
360 dev->pnp.sun = (unsigned long)-1;
364 * If device has _EJ0, 'eject' file is created that is used to trigger
365 * hot-removal function from userland.
367 status = acpi_get_handle(dev->handle, "_EJ0", &temp);
368 if (ACPI_SUCCESS(status))
369 result = device_create_file(&dev->dev, &dev_attr_eject);
374 static void acpi_device_remove_files(struct acpi_device *dev)
380 * If device has _STR, remove 'description' file
382 status = acpi_get_handle(dev->handle, "_STR", &temp);
383 if (ACPI_SUCCESS(status)) {
384 kfree(dev->pnp.str_obj);
385 device_remove_file(&dev->dev, &dev_attr_description);
388 * If device has _EJ0, remove 'eject' file.
390 status = acpi_get_handle(dev->handle, "_EJ0", &temp);
391 if (ACPI_SUCCESS(status))
392 device_remove_file(&dev->dev, &dev_attr_eject);
394 status = acpi_get_handle(dev->handle, "_SUN", &temp);
395 if (ACPI_SUCCESS(status))
396 device_remove_file(&dev->dev, &dev_attr_sun);
398 if (dev->pnp.unique_id)
399 device_remove_file(&dev->dev, &dev_attr_uid);
400 if (dev->flags.bus_address)
401 device_remove_file(&dev->dev, &dev_attr_adr);
402 device_remove_file(&dev->dev, &dev_attr_modalias);
403 device_remove_file(&dev->dev, &dev_attr_hid);
405 device_remove_file(&dev->dev, &dev_attr_path);
407 /* --------------------------------------------------------------------------
409 -------------------------------------------------------------------------- */
411 static const struct acpi_device_id *__acpi_match_device(
412 struct acpi_device *device, const struct acpi_device_id *ids)
414 const struct acpi_device_id *id;
415 struct acpi_hardware_id *hwid;
418 * If the device is not present, it is unnecessary to load device
421 if (!device->status.present)
424 for (id = ids; id->id[0]; id++)
425 list_for_each_entry(hwid, &device->pnp.ids, list)
426 if (!strcmp((char *) id->id, hwid->id))
433 * acpi_match_device - Match a struct device against a given list of ACPI IDs
434 * @ids: Array of struct acpi_device_id object to match against.
435 * @dev: The device structure to match.
437 * Check if @dev has a valid ACPI handle and if there is a struct acpi_device
438 * object for that handle and use that object to match against a given list of
441 * Return a pointer to the first matching ID on success or %NULL on failure.
443 const struct acpi_device_id *acpi_match_device(const struct acpi_device_id *ids,
444 const struct device *dev)
446 struct acpi_device *adev;
447 acpi_handle handle = ACPI_HANDLE(dev);
449 if (!ids || !handle || acpi_bus_get_device(handle, &adev))
452 return __acpi_match_device(adev, ids);
454 EXPORT_SYMBOL_GPL(acpi_match_device);
456 int acpi_match_device_ids(struct acpi_device *device,
457 const struct acpi_device_id *ids)
459 return __acpi_match_device(device, ids) ? 0 : -ENOENT;
461 EXPORT_SYMBOL(acpi_match_device_ids);
463 static void acpi_free_ids(struct acpi_device *device)
465 struct acpi_hardware_id *id, *tmp;
467 list_for_each_entry_safe(id, tmp, &device->pnp.ids, list) {
473 static void acpi_device_release(struct device *dev)
475 struct acpi_device *acpi_dev = to_acpi_device(dev);
477 acpi_free_ids(acpi_dev);
478 kfree(acpi_dev->pnp.unique_id);
482 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
484 struct acpi_device *acpi_dev = to_acpi_device(dev);
485 struct acpi_driver *acpi_drv = to_acpi_driver(drv);
487 return acpi_dev->flags.match_driver
488 && !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
491 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
493 struct acpi_device *acpi_dev = to_acpi_device(dev);
496 if (list_empty(&acpi_dev->pnp.ids))
499 if (add_uevent_var(env, "MODALIAS="))
501 len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
502 sizeof(env->buf) - env->buflen);
503 if (len >= (sizeof(env->buf) - env->buflen))
509 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
511 struct acpi_device *device = data;
513 device->driver->ops.notify(device, event);
516 static acpi_status acpi_device_notify_fixed(void *data)
518 struct acpi_device *device = data;
520 /* Fixed hardware devices have no handles */
521 acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
525 static int acpi_device_install_notify_handler(struct acpi_device *device)
529 if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
531 acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
532 acpi_device_notify_fixed,
534 else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
536 acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
537 acpi_device_notify_fixed,
540 status = acpi_install_notify_handler(device->handle,
545 if (ACPI_FAILURE(status))
550 static void acpi_device_remove_notify_handler(struct acpi_device *device)
552 if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
553 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
554 acpi_device_notify_fixed);
555 else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
556 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
557 acpi_device_notify_fixed);
559 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
563 static int acpi_bus_driver_init(struct acpi_device *, struct acpi_driver *);
564 static int acpi_device_probe(struct device * dev)
566 struct acpi_device *acpi_dev = to_acpi_device(dev);
567 struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
570 ret = acpi_bus_driver_init(acpi_dev, acpi_drv);
572 if (acpi_drv->ops.notify) {
573 ret = acpi_device_install_notify_handler(acpi_dev);
575 if (acpi_drv->ops.remove)
576 acpi_drv->ops.remove(acpi_dev,
577 acpi_dev->removal_type);
582 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
583 "Found driver [%s] for device [%s]\n",
584 acpi_drv->name, acpi_dev->pnp.bus_id));
590 static int acpi_device_remove(struct device * dev)
592 struct acpi_device *acpi_dev = to_acpi_device(dev);
593 struct acpi_driver *acpi_drv = acpi_dev->driver;
596 if (acpi_drv->ops.notify)
597 acpi_device_remove_notify_handler(acpi_dev);
598 if (acpi_drv->ops.remove)
599 acpi_drv->ops.remove(acpi_dev, acpi_dev->removal_type);
601 acpi_dev->driver = NULL;
602 acpi_dev->driver_data = NULL;
608 struct bus_type acpi_bus_type = {
610 .match = acpi_bus_match,
611 .probe = acpi_device_probe,
612 .remove = acpi_device_remove,
613 .uevent = acpi_device_uevent,
616 static int acpi_device_register(struct acpi_device *device)
619 struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
625 * Link this device to its parent and siblings.
627 INIT_LIST_HEAD(&device->children);
628 INIT_LIST_HEAD(&device->node);
629 INIT_LIST_HEAD(&device->wakeup_list);
630 INIT_LIST_HEAD(&device->physical_node_list);
631 mutex_init(&device->physical_node_lock);
633 new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
635 printk(KERN_ERR PREFIX "Memory allocation error\n");
639 mutex_lock(&acpi_device_lock);
641 * Find suitable bus_id and instance number in acpi_bus_id_list
642 * If failed, create one and link it into acpi_bus_id_list
644 list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
645 if (!strcmp(acpi_device_bus_id->bus_id,
646 acpi_device_hid(device))) {
647 acpi_device_bus_id->instance_no++;
654 acpi_device_bus_id = new_bus_id;
655 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
656 acpi_device_bus_id->instance_no = 0;
657 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
659 dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
662 list_add_tail(&device->node, &device->parent->children);
664 if (device->wakeup.flags.valid)
665 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
666 mutex_unlock(&acpi_device_lock);
669 device->dev.parent = &device->parent->dev;
670 device->dev.bus = &acpi_bus_type;
671 device->dev.release = &acpi_device_release;
672 result = device_register(&device->dev);
674 dev_err(&device->dev, "Error registering device\n");
678 result = acpi_device_setup_files(device);
680 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
681 dev_name(&device->dev));
683 device->removal_type = ACPI_BUS_REMOVAL_NORMAL;
686 mutex_lock(&acpi_device_lock);
688 list_del(&device->node);
689 list_del(&device->wakeup_list);
690 mutex_unlock(&acpi_device_lock);
694 static void acpi_device_unregister(struct acpi_device *device)
696 mutex_lock(&acpi_device_lock);
698 list_del(&device->node);
700 list_del(&device->wakeup_list);
701 mutex_unlock(&acpi_device_lock);
703 acpi_detach_data(device->handle, acpi_bus_data_handler);
705 acpi_device_remove_files(device);
706 device_unregister(&device->dev);
709 /* --------------------------------------------------------------------------
711 -------------------------------------------------------------------------- */
713 * acpi_bus_driver_init - add a device to a driver
714 * @device: the device to add and initialize
715 * @driver: driver for the device
717 * Used to initialize a device via its device driver. Called whenever a
718 * driver is bound to a device. Invokes the driver's add() ops.
721 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
725 if (!device || !driver)
728 if (!driver->ops.add)
731 result = driver->ops.add(device);
733 device->driver = NULL;
734 device->driver_data = NULL;
738 device->driver = driver;
741 * TBD - Configuration Management: Assign resources to device based
742 * upon possible configuration and currently allocated resources.
745 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
746 "Driver successfully bound to device\n"));
751 * acpi_bus_register_driver - register a driver with the ACPI bus
752 * @driver: driver being registered
754 * Registers a driver with the ACPI bus. Searches the namespace for all
755 * devices that match the driver's criteria and binds. Returns zero for
756 * success or a negative error status for failure.
758 int acpi_bus_register_driver(struct acpi_driver *driver)
764 driver->drv.name = driver->name;
765 driver->drv.bus = &acpi_bus_type;
766 driver->drv.owner = driver->owner;
768 ret = driver_register(&driver->drv);
772 EXPORT_SYMBOL(acpi_bus_register_driver);
775 * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
776 * @driver: driver to unregister
778 * Unregisters a driver with the ACPI bus. Searches the namespace for all
779 * devices that match the driver's criteria and unbinds.
781 void acpi_bus_unregister_driver(struct acpi_driver *driver)
783 driver_unregister(&driver->drv);
786 EXPORT_SYMBOL(acpi_bus_unregister_driver);
788 /* --------------------------------------------------------------------------
790 -------------------------------------------------------------------------- */
791 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
795 struct acpi_device *device;
798 * Fixed hardware devices do not appear in the namespace and do not
799 * have handles, but we fabricate acpi_devices for them, so we have
800 * to deal with them specially.
806 status = acpi_get_parent(handle, &handle);
807 if (status == AE_NULL_ENTRY)
809 if (ACPI_FAILURE(status))
812 ret = acpi_bus_get_device(handle, &device);
819 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
823 struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
824 union acpi_object *obj;
826 status = acpi_get_handle(handle, "_EJD", &tmp);
827 if (ACPI_FAILURE(status))
830 status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
831 if (ACPI_SUCCESS(status)) {
832 obj = buffer.pointer;
833 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
835 kfree(buffer.pointer);
839 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
841 void acpi_bus_data_handler(acpi_handle handle, void *context)
849 static int acpi_bus_get_perf_flags(struct acpi_device *device)
851 device->performance.state = ACPI_STATE_UNKNOWN;
856 acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
857 struct acpi_device_wakeup *wakeup)
859 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
860 union acpi_object *package = NULL;
861 union acpi_object *element = NULL;
866 return AE_BAD_PARAMETER;
869 status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
870 if (ACPI_FAILURE(status)) {
871 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
875 package = (union acpi_object *)buffer.pointer;
877 if (!package || (package->package.count < 2)) {
878 status = AE_BAD_DATA;
882 element = &(package->package.elements[0]);
884 status = AE_BAD_DATA;
887 if (element->type == ACPI_TYPE_PACKAGE) {
888 if ((element->package.count < 2) ||
889 (element->package.elements[0].type !=
890 ACPI_TYPE_LOCAL_REFERENCE)
891 || (element->package.elements[1].type != ACPI_TYPE_INTEGER)) {
892 status = AE_BAD_DATA;
896 element->package.elements[0].reference.handle;
898 (u32) element->package.elements[1].integer.value;
899 } else if (element->type == ACPI_TYPE_INTEGER) {
900 wakeup->gpe_device = NULL;
901 wakeup->gpe_number = element->integer.value;
903 status = AE_BAD_DATA;
907 element = &(package->package.elements[1]);
908 if (element->type != ACPI_TYPE_INTEGER) {
909 status = AE_BAD_DATA;
912 wakeup->sleep_state = element->integer.value;
914 if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
915 status = AE_NO_MEMORY;
918 wakeup->resources.count = package->package.count - 2;
919 for (i = 0; i < wakeup->resources.count; i++) {
920 element = &(package->package.elements[i + 2]);
921 if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
922 status = AE_BAD_DATA;
926 wakeup->resources.handles[i] = element->reference.handle;
929 acpi_setup_gpe_for_wake(handle, wakeup->gpe_device, wakeup->gpe_number);
932 kfree(buffer.pointer);
937 static void acpi_bus_set_run_wake_flags(struct acpi_device *device)
939 struct acpi_device_id button_device_ids[] = {
946 acpi_event_status event_status;
948 device->wakeup.flags.notifier_present = 0;
950 /* Power button, Lid switch always enable wakeup */
951 if (!acpi_match_device_ids(device, button_device_ids)) {
952 device->wakeup.flags.run_wake = 1;
953 if (!acpi_match_device_ids(device, &button_device_ids[1])) {
954 /* Do not use Lid/sleep button for S5 wakeup */
955 if (device->wakeup.sleep_state == ACPI_STATE_S5)
956 device->wakeup.sleep_state = ACPI_STATE_S4;
958 device_set_wakeup_capable(&device->dev, true);
962 status = acpi_get_gpe_status(device->wakeup.gpe_device,
963 device->wakeup.gpe_number,
966 device->wakeup.flags.run_wake =
967 !!(event_status & ACPI_EVENT_FLAG_HANDLE);
970 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
973 acpi_status status = 0;
976 /* Presence of _PRW indicates wake capable */
977 status = acpi_get_handle(device->handle, "_PRW", &temp);
978 if (ACPI_FAILURE(status))
981 status = acpi_bus_extract_wakeup_device_power_package(device->handle,
983 if (ACPI_FAILURE(status)) {
984 ACPI_EXCEPTION((AE_INFO, status, "Extracting _PRW package"));
988 device->wakeup.flags.valid = 1;
989 device->wakeup.prepare_count = 0;
990 acpi_bus_set_run_wake_flags(device);
991 /* Call _PSW/_DSW object to disable its ability to wake the sleeping
992 * system for the ACPI device with the _PRW object.
993 * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
994 * So it is necessary to call _DSW object first. Only when it is not
995 * present will the _PSW object used.
997 psw_error = acpi_device_sleep_wake(device, 0, 0, 0);
999 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1000 "error in _DSW or _PSW evaluation\n"));
1003 static void acpi_bus_add_power_resource(acpi_handle handle);
1005 static int acpi_bus_get_power_flags(struct acpi_device *device)
1007 acpi_status status = 0;
1008 acpi_handle handle = NULL;
1013 * Power Management Flags
1015 status = acpi_get_handle(device->handle, "_PSC", &handle);
1016 if (ACPI_SUCCESS(status))
1017 device->power.flags.explicit_get = 1;
1018 status = acpi_get_handle(device->handle, "_IRC", &handle);
1019 if (ACPI_SUCCESS(status))
1020 device->power.flags.inrush_current = 1;
1023 * Enumerate supported power management states
1025 for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
1026 struct acpi_device_power_state *ps = &device->power.states[i];
1027 char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
1029 /* Evaluate "_PRx" to se if power resources are referenced */
1030 acpi_evaluate_reference(device->handle, object_name, NULL,
1032 if (ps->resources.count) {
1035 device->power.flags.power_resources = 1;
1036 for (j = 0; j < ps->resources.count; j++)
1037 acpi_bus_add_power_resource(ps->resources.handles[j]);
1040 /* Evaluate "_PSx" to see if we can do explicit sets */
1041 object_name[2] = 'S';
1042 status = acpi_get_handle(device->handle, object_name, &handle);
1043 if (ACPI_SUCCESS(status))
1044 ps->flags.explicit_set = 1;
1047 * State is valid if there are means to put the device into it.
1048 * D3hot is only valid if _PR3 present.
1050 if (ps->resources.count ||
1051 (ps->flags.explicit_set && i < ACPI_STATE_D3_HOT)) {
1052 ps->flags.valid = 1;
1053 ps->flags.os_accessible = 1;
1056 ps->power = -1; /* Unknown - driver assigned */
1057 ps->latency = -1; /* Unknown - driver assigned */
1060 /* Set defaults for D0 and D3 states (always valid) */
1061 device->power.states[ACPI_STATE_D0].flags.valid = 1;
1062 device->power.states[ACPI_STATE_D0].power = 100;
1063 device->power.states[ACPI_STATE_D3].flags.valid = 1;
1064 device->power.states[ACPI_STATE_D3].power = 0;
1066 /* Set D3cold's explicit_set flag if _PS3 exists. */
1067 if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set)
1068 device->power.states[ACPI_STATE_D3_COLD].flags.explicit_set = 1;
1070 /* Presence of _PS3 or _PRx means we can put the device into D3 cold */
1071 if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set ||
1072 device->power.flags.power_resources)
1073 device->power.states[ACPI_STATE_D3_COLD].flags.os_accessible = 1;
1075 acpi_bus_init_power(device);
1080 static int acpi_bus_get_flags(struct acpi_device *device)
1082 acpi_status status = AE_OK;
1083 acpi_handle temp = NULL;
1086 /* Presence of _STA indicates 'dynamic_status' */
1087 status = acpi_get_handle(device->handle, "_STA", &temp);
1088 if (ACPI_SUCCESS(status))
1089 device->flags.dynamic_status = 1;
1091 /* Presence of _RMV indicates 'removable' */
1092 status = acpi_get_handle(device->handle, "_RMV", &temp);
1093 if (ACPI_SUCCESS(status))
1094 device->flags.removable = 1;
1096 /* Presence of _EJD|_EJ0 indicates 'ejectable' */
1097 status = acpi_get_handle(device->handle, "_EJD", &temp);
1098 if (ACPI_SUCCESS(status))
1099 device->flags.ejectable = 1;
1101 status = acpi_get_handle(device->handle, "_EJ0", &temp);
1102 if (ACPI_SUCCESS(status))
1103 device->flags.ejectable = 1;
1106 /* Power resources cannot be power manageable. */
1107 if (device->device_type == ACPI_BUS_TYPE_POWER)
1110 /* Presence of _PS0|_PR0 indicates 'power manageable' */
1111 status = acpi_get_handle(device->handle, "_PS0", &temp);
1112 if (ACPI_FAILURE(status))
1113 status = acpi_get_handle(device->handle, "_PR0", &temp);
1114 if (ACPI_SUCCESS(status))
1115 device->flags.power_manageable = 1;
1117 /* TBD: Performance management */
1122 static void acpi_device_get_busid(struct acpi_device *device)
1124 char bus_id[5] = { '?', 0 };
1125 struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1131 * The device's Bus ID is simply the object name.
1132 * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1134 if (ACPI_IS_ROOT_DEVICE(device)) {
1135 strcpy(device->pnp.bus_id, "ACPI");
1139 switch (device->device_type) {
1140 case ACPI_BUS_TYPE_POWER_BUTTON:
1141 strcpy(device->pnp.bus_id, "PWRF");
1143 case ACPI_BUS_TYPE_SLEEP_BUTTON:
1144 strcpy(device->pnp.bus_id, "SLPF");
1147 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1148 /* Clean up trailing underscores (if any) */
1149 for (i = 3; i > 1; i--) {
1150 if (bus_id[i] == '_')
1155 strcpy(device->pnp.bus_id, bus_id);
1161 * acpi_bay_match - see if a device is an ejectable driver bay
1163 * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1164 * then we can safely call it an ejectable drive bay
1166 static int acpi_bay_match(struct acpi_device *device){
1170 acpi_handle phandle;
1172 handle = device->handle;
1174 status = acpi_get_handle(handle, "_EJ0", &tmp);
1175 if (ACPI_FAILURE(status))
1178 if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
1179 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
1180 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
1181 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
1184 if (acpi_get_parent(handle, &phandle))
1187 if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
1188 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
1189 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
1190 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
1197 * acpi_dock_match - see if a device has a _DCK method
1199 static int acpi_dock_match(struct acpi_device *device)
1202 return acpi_get_handle(device->handle, "_DCK", &tmp);
1205 const char *acpi_device_hid(struct acpi_device *device)
1207 struct acpi_hardware_id *hid;
1209 if (list_empty(&device->pnp.ids))
1212 hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1215 EXPORT_SYMBOL(acpi_device_hid);
1217 static void acpi_add_id(struct acpi_device *device, const char *dev_id)
1219 struct acpi_hardware_id *id;
1221 id = kmalloc(sizeof(*id), GFP_KERNEL);
1225 id->id = kstrdup(dev_id, GFP_KERNEL);
1231 list_add_tail(&id->list, &device->pnp.ids);
1235 * Old IBM workstations have a DSDT bug wherein the SMBus object
1236 * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1237 * prefix. Work around this.
1239 static int acpi_ibm_smbus_match(struct acpi_device *device)
1241 acpi_handle h_dummy;
1242 struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
1245 if (!dmi_name_in_vendors("IBM"))
1248 /* Look for SMBS object */
1249 result = acpi_get_name(device->handle, ACPI_SINGLE_NAME, &path);
1253 if (strcmp("SMBS", path.pointer)) {
1258 /* Does it have the necessary (but misnamed) methods? */
1260 if (ACPI_SUCCESS(acpi_get_handle(device->handle, "SBI", &h_dummy)) &&
1261 ACPI_SUCCESS(acpi_get_handle(device->handle, "SBR", &h_dummy)) &&
1262 ACPI_SUCCESS(acpi_get_handle(device->handle, "SBW", &h_dummy)))
1265 kfree(path.pointer);
1269 static void acpi_device_set_id(struct acpi_device *device)
1272 struct acpi_device_info *info;
1273 struct acpi_pnp_device_id_list *cid_list;
1276 switch (device->device_type) {
1277 case ACPI_BUS_TYPE_DEVICE:
1278 if (ACPI_IS_ROOT_DEVICE(device)) {
1279 acpi_add_id(device, ACPI_SYSTEM_HID);
1283 status = acpi_get_object_info(device->handle, &info);
1284 if (ACPI_FAILURE(status)) {
1285 printk(KERN_ERR PREFIX "%s: Error reading device info\n", __func__);
1289 if (info->valid & ACPI_VALID_HID)
1290 acpi_add_id(device, info->hardware_id.string);
1291 if (info->valid & ACPI_VALID_CID) {
1292 cid_list = &info->compatible_id_list;
1293 for (i = 0; i < cid_list->count; i++)
1294 acpi_add_id(device, cid_list->ids[i].string);
1296 if (info->valid & ACPI_VALID_ADR) {
1297 device->pnp.bus_address = info->address;
1298 device->flags.bus_address = 1;
1300 if (info->valid & ACPI_VALID_UID)
1301 device->pnp.unique_id = kstrdup(info->unique_id.string,
1307 * Some devices don't reliably have _HIDs & _CIDs, so add
1308 * synthetic HIDs to make sure drivers can find them.
1310 if (acpi_is_video_device(device))
1311 acpi_add_id(device, ACPI_VIDEO_HID);
1312 else if (ACPI_SUCCESS(acpi_bay_match(device)))
1313 acpi_add_id(device, ACPI_BAY_HID);
1314 else if (ACPI_SUCCESS(acpi_dock_match(device)))
1315 acpi_add_id(device, ACPI_DOCK_HID);
1316 else if (!acpi_ibm_smbus_match(device))
1317 acpi_add_id(device, ACPI_SMBUS_IBM_HID);
1318 else if (list_empty(&device->pnp.ids) &&
1319 ACPI_IS_ROOT_DEVICE(device->parent)) {
1320 acpi_add_id(device, ACPI_BUS_HID); /* \_SB, LNXSYBUS */
1321 strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
1322 strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
1326 case ACPI_BUS_TYPE_POWER:
1327 acpi_add_id(device, ACPI_POWER_HID);
1329 case ACPI_BUS_TYPE_PROCESSOR:
1330 acpi_add_id(device, ACPI_PROCESSOR_OBJECT_HID);
1332 case ACPI_BUS_TYPE_THERMAL:
1333 acpi_add_id(device, ACPI_THERMAL_HID);
1335 case ACPI_BUS_TYPE_POWER_BUTTON:
1336 acpi_add_id(device, ACPI_BUTTON_HID_POWERF);
1338 case ACPI_BUS_TYPE_SLEEP_BUTTON:
1339 acpi_add_id(device, ACPI_BUTTON_HID_SLEEPF);
1344 static int acpi_device_set_context(struct acpi_device *device)
1351 * Attach this 'struct acpi_device' to the ACPI object. This makes
1352 * resolutions from handle->device very efficient. Fixed hardware
1353 * devices have no handles, so we skip them.
1355 if (!device->handle)
1358 status = acpi_attach_data(device->handle,
1359 acpi_bus_data_handler, device);
1360 if (ACPI_SUCCESS(status))
1363 printk(KERN_ERR PREFIX "Error attaching device data\n");
1367 static int acpi_add_single_object(struct acpi_device **child,
1368 acpi_handle handle, int type,
1369 unsigned long long sta, bool match_driver)
1372 struct acpi_device *device;
1373 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1375 device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1377 printk(KERN_ERR PREFIX "Memory allocation error\n");
1381 INIT_LIST_HEAD(&device->pnp.ids);
1382 device->device_type = type;
1383 device->handle = handle;
1384 device->parent = acpi_bus_get_parent(handle);
1385 STRUCT_TO_INT(device->status) = sta;
1387 acpi_device_get_busid(device);
1392 * Note that we only look for object handles -- cannot evaluate objects
1393 * until we know the device is present and properly initialized.
1395 result = acpi_bus_get_flags(device);
1402 * TBD: Synch with Core's enumeration/initialization process.
1404 acpi_device_set_id(device);
1410 if (device->flags.power_manageable) {
1411 result = acpi_bus_get_power_flags(device);
1417 * Wakeup device management
1418 *-----------------------
1420 acpi_bus_get_wakeup_device_flags(device);
1423 * Performance Management
1424 * ----------------------
1426 if (device->flags.performance_manageable) {
1427 result = acpi_bus_get_perf_flags(device);
1432 if ((result = acpi_device_set_context(device)))
1435 device->flags.match_driver = match_driver;
1436 result = acpi_device_register(device);
1440 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1441 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1442 "Adding %s [%s] parent %s\n", dev_name(&device->dev),
1443 (char *) buffer.pointer,
1444 device->parent ? dev_name(&device->parent->dev) :
1446 kfree(buffer.pointer);
1449 acpi_device_release(&device->dev);
1454 #define ACPI_STA_DEFAULT (ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED | \
1455 ACPI_STA_DEVICE_UI | ACPI_STA_DEVICE_FUNCTIONING)
1457 static void acpi_bus_add_power_resource(acpi_handle handle)
1459 struct acpi_device *device = NULL;
1461 acpi_bus_get_device(handle, &device);
1463 acpi_add_single_object(&device, handle, ACPI_BUS_TYPE_POWER,
1464 ACPI_STA_DEFAULT, true);
1467 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1468 unsigned long long *sta)
1471 acpi_object_type acpi_type;
1473 status = acpi_get_type(handle, &acpi_type);
1474 if (ACPI_FAILURE(status))
1477 switch (acpi_type) {
1478 case ACPI_TYPE_ANY: /* for ACPI_ROOT_OBJECT */
1479 case ACPI_TYPE_DEVICE:
1480 *type = ACPI_BUS_TYPE_DEVICE;
1481 status = acpi_bus_get_status_handle(handle, sta);
1482 if (ACPI_FAILURE(status))
1485 case ACPI_TYPE_PROCESSOR:
1486 *type = ACPI_BUS_TYPE_PROCESSOR;
1487 status = acpi_bus_get_status_handle(handle, sta);
1488 if (ACPI_FAILURE(status))
1491 case ACPI_TYPE_THERMAL:
1492 *type = ACPI_BUS_TYPE_THERMAL;
1493 *sta = ACPI_STA_DEFAULT;
1495 case ACPI_TYPE_POWER:
1496 *type = ACPI_BUS_TYPE_POWER;
1497 *sta = ACPI_STA_DEFAULT;
1506 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
1507 void *not_used, void **return_value)
1509 struct acpi_device *device = NULL;
1511 unsigned long long sta;
1515 acpi_bus_get_device(handle, &device);
1519 result = acpi_bus_type_and_status(handle, &type, &sta);
1523 if (!(sta & ACPI_STA_DEVICE_PRESENT) &&
1524 !(sta & ACPI_STA_DEVICE_FUNCTIONING)) {
1525 struct acpi_device_wakeup wakeup;
1528 status = acpi_get_handle(handle, "_PRW", &temp);
1529 if (ACPI_SUCCESS(status))
1530 acpi_bus_extract_wakeup_device_power_package(handle,
1532 return AE_CTRL_DEPTH;
1535 acpi_add_single_object(&device, handle, type, sta,
1536 type == ACPI_BUS_TYPE_POWER);
1538 return AE_CTRL_DEPTH;
1540 device->flags.match_driver = true;
1544 *return_value = device;
1549 static acpi_status acpi_bus_device_attach(acpi_handle handle, u32 lvl_not_used,
1550 void *not_used, void **ret_not_used)
1552 acpi_status status = AE_OK;
1553 struct acpi_device *device;
1554 unsigned long long sta_not_used;
1558 * Ignore errors ignored by acpi_bus_check_add() to avoid terminating
1559 * namespace walks prematurely.
1561 if (acpi_bus_type_and_status(handle, &type_not_used, &sta_not_used))
1564 if (acpi_bus_get_device(handle, &device))
1565 return AE_CTRL_DEPTH;
1567 if (!acpi_match_device_ids(device, acpi_platform_device_ids)) {
1568 /* This is a known good platform device. */
1569 acpi_create_platform_device(device);
1570 } else if (device_attach(&device->dev) < 0) {
1571 status = AE_CTRL_DEPTH;
1577 * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
1578 * @handle: Root of the namespace scope to scan.
1580 * Scan a given ACPI tree (probably recently hot-plugged) and create and add
1583 * If no devices were found, -ENODEV is returned, but it does not mean that
1584 * there has been a real error. There just have been no suitable ACPI objects
1585 * in the table trunk from which the kernel could create a device and add an
1586 * appropriate driver.
1588 int acpi_bus_scan(acpi_handle handle)
1590 void *device = NULL;
1593 mutex_lock(&acpi_scan_lock);
1595 if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
1596 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1597 acpi_bus_check_add, NULL, NULL, &device);
1601 else if (ACPI_SUCCESS(acpi_bus_device_attach(handle, 0, NULL, NULL)))
1602 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1603 acpi_bus_device_attach, NULL, NULL, NULL);
1605 mutex_unlock(&acpi_scan_lock);
1608 EXPORT_SYMBOL(acpi_bus_scan);
1610 static acpi_status acpi_bus_device_detach(acpi_handle handle, u32 lvl_not_used,
1611 void *not_used, void **ret_not_used)
1613 struct acpi_device *device = NULL;
1615 if (!acpi_bus_get_device(handle, &device)) {
1616 device->removal_type = ACPI_BUS_REMOVAL_EJECT;
1617 device_release_driver(&device->dev);
1622 static acpi_status acpi_bus_remove(acpi_handle handle, u32 lvl_not_used,
1623 void *not_used, void **ret_not_used)
1625 struct acpi_device *device = NULL;
1627 if (!acpi_bus_get_device(handle, &device))
1628 acpi_device_unregister(device);
1633 void acpi_bus_trim(struct acpi_device *start)
1635 mutex_lock(&acpi_scan_lock);
1638 * Execute acpi_bus_device_detach() as a post-order callback to detach
1639 * all ACPI drivers from the device nodes being removed.
1641 acpi_walk_namespace(ACPI_TYPE_ANY, start->handle, ACPI_UINT32_MAX, NULL,
1642 acpi_bus_device_detach, NULL, NULL);
1643 acpi_bus_device_detach(start->handle, 0, NULL, NULL);
1645 * Execute acpi_bus_remove() as a post-order callback to remove device
1646 * nodes in the given namespace scope.
1648 acpi_walk_namespace(ACPI_TYPE_ANY, start->handle, ACPI_UINT32_MAX, NULL,
1649 acpi_bus_remove, NULL, NULL);
1650 acpi_bus_remove(start->handle, 0, NULL, NULL);
1652 mutex_unlock(&acpi_scan_lock);
1654 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1656 static int acpi_bus_scan_fixed(void)
1659 struct acpi_device *device = NULL;
1662 * Enumerate all fixed-feature devices.
1664 if ((acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON) == 0) {
1665 result = acpi_add_single_object(&device, NULL,
1666 ACPI_BUS_TYPE_POWER_BUTTON,
1667 ACPI_STA_DEFAULT, true);
1668 device_init_wakeup(&device->dev, true);
1671 if ((acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON) == 0) {
1672 result = acpi_add_single_object(&device, NULL,
1673 ACPI_BUS_TYPE_SLEEP_BUTTON,
1674 ACPI_STA_DEFAULT, true);
1680 int __init acpi_scan_init(void)
1684 result = bus_register(&acpi_bus_type);
1686 /* We don't want to quit even if we failed to add suspend/resume */
1687 printk(KERN_ERR PREFIX "Could not register bus type\n");
1691 acpi_pci_root_init();
1694 * Enumerate devices in the ACPI namespace.
1696 result = acpi_bus_scan(ACPI_ROOT_OBJECT);
1700 result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
1704 result = acpi_bus_scan_fixed();
1706 acpi_device_unregister(acpi_root);
1710 acpi_update_all_gpes();