x86, pat: Fix set_memory_wc related corruption
[linux-2.6/mini2440.git] / drivers / acpi / scan.c
blob781435d7e3692026d81cb6f112e7e422aa00a7dc
1 /*
2 * scan.c - support for transforming the ACPI namespace into individual objects
3 */
5 #include <linux/module.h>
6 #include <linux/init.h>
7 #include <linux/kernel.h>
8 #include <linux/acpi.h>
9 #include <linux/signal.h>
10 #include <linux/kthread.h>
12 #include <acpi/acpi_drivers.h>
14 #include "internal.h"
16 #define _COMPONENT ACPI_BUS_COMPONENT
17 ACPI_MODULE_NAME("scan");
18 #define STRUCT_TO_INT(s) (*((int*)&s))
19 extern struct acpi_device *acpi_root;
21 #define ACPI_BUS_CLASS "system_bus"
22 #define ACPI_BUS_HID "LNXSYBUS"
23 #define ACPI_BUS_DEVICE_NAME "System Bus"
25 static LIST_HEAD(acpi_device_list);
26 static LIST_HEAD(acpi_bus_id_list);
27 DEFINE_MUTEX(acpi_device_lock);
28 LIST_HEAD(acpi_wakeup_device_list);
30 struct acpi_device_bus_id{
31 char bus_id[15];
32 unsigned int instance_no;
33 struct list_head node;
37 * Creates hid/cid(s) string needed for modalias and uevent
38 * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
39 * char *modalias: "acpi:IBM0001:ACPI0001"
41 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
42 int size)
44 int len;
45 int count;
47 if (!acpi_dev->flags.hardware_id && !acpi_dev->flags.compatible_ids)
48 return -ENODEV;
50 len = snprintf(modalias, size, "acpi:");
51 size -= len;
53 if (acpi_dev->flags.hardware_id) {
54 count = snprintf(&modalias[len], size, "%s:",
55 acpi_dev->pnp.hardware_id);
56 if (count < 0 || count >= size)
57 return -EINVAL;
58 len += count;
59 size -= count;
62 if (acpi_dev->flags.compatible_ids) {
63 struct acpi_compatible_id_list *cid_list;
64 int i;
66 cid_list = acpi_dev->pnp.cid_list;
67 for (i = 0; i < cid_list->count; i++) {
68 count = snprintf(&modalias[len], size, "%s:",
69 cid_list->id[i].value);
70 if (count < 0 || count >= size) {
71 printk(KERN_ERR PREFIX "%s cid[%i] exceeds event buffer size",
72 acpi_dev->pnp.device_name, i);
73 break;
75 len += count;
76 size -= count;
80 modalias[len] = '\0';
81 return len;
84 static ssize_t
85 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
86 struct acpi_device *acpi_dev = to_acpi_device(dev);
87 int len;
89 /* Device has no HID and no CID or string is >1024 */
90 len = create_modalias(acpi_dev, buf, 1024);
91 if (len <= 0)
92 return 0;
93 buf[len++] = '\n';
94 return len;
96 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
98 static void acpi_bus_hot_remove_device(void *context)
100 struct acpi_device *device;
101 acpi_handle handle = context;
102 struct acpi_object_list arg_list;
103 union acpi_object arg;
104 acpi_status status = AE_OK;
106 if (acpi_bus_get_device(handle, &device))
107 return;
109 if (!device)
110 return;
112 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
113 "Hot-removing device %s...\n", dev_name(&device->dev)));
115 if (acpi_bus_trim(device, 1)) {
116 printk(KERN_ERR PREFIX
117 "Removing device failed\n");
118 return;
121 /* power off device */
122 status = acpi_evaluate_object(handle, "_PS3", NULL, NULL);
123 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
124 printk(KERN_WARNING PREFIX
125 "Power-off device failed\n");
127 if (device->flags.lockable) {
128 arg_list.count = 1;
129 arg_list.pointer = &arg;
130 arg.type = ACPI_TYPE_INTEGER;
131 arg.integer.value = 0;
132 acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
135 arg_list.count = 1;
136 arg_list.pointer = &arg;
137 arg.type = ACPI_TYPE_INTEGER;
138 arg.integer.value = 1;
141 * TBD: _EJD support.
143 status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
144 if (ACPI_FAILURE(status))
145 printk(KERN_WARNING PREFIX
146 "Eject device failed\n");
148 return;
151 static ssize_t
152 acpi_eject_store(struct device *d, struct device_attribute *attr,
153 const char *buf, size_t count)
155 int ret = count;
156 acpi_status status;
157 acpi_object_type type = 0;
158 struct acpi_device *acpi_device = to_acpi_device(d);
160 if ((!count) || (buf[0] != '1')) {
161 return -EINVAL;
163 #ifndef FORCE_EJECT
164 if (acpi_device->driver == NULL) {
165 ret = -ENODEV;
166 goto err;
168 #endif
169 status = acpi_get_type(acpi_device->handle, &type);
170 if (ACPI_FAILURE(status) || (!acpi_device->flags.ejectable)) {
171 ret = -ENODEV;
172 goto err;
175 acpi_os_hotplug_execute(acpi_bus_hot_remove_device, acpi_device->handle);
176 err:
177 return ret;
180 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
182 static ssize_t
183 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
184 struct acpi_device *acpi_dev = to_acpi_device(dev);
186 return sprintf(buf, "%s\n", acpi_dev->pnp.hardware_id);
188 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
190 static ssize_t
191 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
192 struct acpi_device *acpi_dev = to_acpi_device(dev);
193 struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
194 int result;
196 result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
197 if (result)
198 goto end;
200 result = sprintf(buf, "%s\n", (char*)path.pointer);
201 kfree(path.pointer);
202 end:
203 return result;
205 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
207 static int acpi_device_setup_files(struct acpi_device *dev)
209 acpi_status status;
210 acpi_handle temp;
211 int result = 0;
214 * Devices gotten from FADT don't have a "path" attribute
216 if (dev->handle) {
217 result = device_create_file(&dev->dev, &dev_attr_path);
218 if (result)
219 goto end;
222 if (dev->flags.hardware_id) {
223 result = device_create_file(&dev->dev, &dev_attr_hid);
224 if (result)
225 goto end;
228 if (dev->flags.hardware_id || dev->flags.compatible_ids) {
229 result = device_create_file(&dev->dev, &dev_attr_modalias);
230 if (result)
231 goto end;
235 * If device has _EJ0, 'eject' file is created that is used to trigger
236 * hot-removal function from userland.
238 status = acpi_get_handle(dev->handle, "_EJ0", &temp);
239 if (ACPI_SUCCESS(status))
240 result = device_create_file(&dev->dev, &dev_attr_eject);
241 end:
242 return result;
245 static void acpi_device_remove_files(struct acpi_device *dev)
247 acpi_status status;
248 acpi_handle temp;
251 * If device has _EJ0, 'eject' file is created that is used to trigger
252 * hot-removal function from userland.
254 status = acpi_get_handle(dev->handle, "_EJ0", &temp);
255 if (ACPI_SUCCESS(status))
256 device_remove_file(&dev->dev, &dev_attr_eject);
258 if (dev->flags.hardware_id || dev->flags.compatible_ids)
259 device_remove_file(&dev->dev, &dev_attr_modalias);
261 if (dev->flags.hardware_id)
262 device_remove_file(&dev->dev, &dev_attr_hid);
263 if (dev->handle)
264 device_remove_file(&dev->dev, &dev_attr_path);
266 /* --------------------------------------------------------------------------
267 ACPI Bus operations
268 -------------------------------------------------------------------------- */
270 int acpi_match_device_ids(struct acpi_device *device,
271 const struct acpi_device_id *ids)
273 const struct acpi_device_id *id;
276 * If the device is not present, it is unnecessary to load device
277 * driver for it.
279 if (!device->status.present)
280 return -ENODEV;
282 if (device->flags.hardware_id) {
283 for (id = ids; id->id[0]; id++) {
284 if (!strcmp((char*)id->id, device->pnp.hardware_id))
285 return 0;
289 if (device->flags.compatible_ids) {
290 struct acpi_compatible_id_list *cid_list = device->pnp.cid_list;
291 int i;
293 for (id = ids; id->id[0]; id++) {
294 /* compare multiple _CID entries against driver ids */
295 for (i = 0; i < cid_list->count; i++) {
296 if (!strcmp((char*)id->id,
297 cid_list->id[i].value))
298 return 0;
303 return -ENOENT;
305 EXPORT_SYMBOL(acpi_match_device_ids);
307 static void acpi_device_release(struct device *dev)
309 struct acpi_device *acpi_dev = to_acpi_device(dev);
311 kfree(acpi_dev->pnp.cid_list);
312 kfree(acpi_dev);
315 static int acpi_device_suspend(struct device *dev, pm_message_t state)
317 struct acpi_device *acpi_dev = to_acpi_device(dev);
318 struct acpi_driver *acpi_drv = acpi_dev->driver;
320 if (acpi_drv && acpi_drv->ops.suspend)
321 return acpi_drv->ops.suspend(acpi_dev, state);
322 return 0;
325 static int acpi_device_resume(struct device *dev)
327 struct acpi_device *acpi_dev = to_acpi_device(dev);
328 struct acpi_driver *acpi_drv = acpi_dev->driver;
330 if (acpi_drv && acpi_drv->ops.resume)
331 return acpi_drv->ops.resume(acpi_dev);
332 return 0;
335 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
337 struct acpi_device *acpi_dev = to_acpi_device(dev);
338 struct acpi_driver *acpi_drv = to_acpi_driver(drv);
340 return !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
343 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
345 struct acpi_device *acpi_dev = to_acpi_device(dev);
346 int len;
348 if (add_uevent_var(env, "MODALIAS="))
349 return -ENOMEM;
350 len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
351 sizeof(env->buf) - env->buflen);
352 if (len >= (sizeof(env->buf) - env->buflen))
353 return -ENOMEM;
354 env->buflen += len;
355 return 0;
358 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
360 struct acpi_device *device = data;
362 device->driver->ops.notify(device, event);
365 static acpi_status acpi_device_notify_fixed(void *data)
367 struct acpi_device *device = data;
369 acpi_device_notify(device->handle, ACPI_FIXED_HARDWARE_EVENT, device);
370 return AE_OK;
373 static int acpi_device_install_notify_handler(struct acpi_device *device)
375 acpi_status status;
376 char *hid;
378 hid = acpi_device_hid(device);
379 if (!strcmp(hid, ACPI_BUTTON_HID_POWERF))
380 status =
381 acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
382 acpi_device_notify_fixed,
383 device);
384 else if (!strcmp(hid, ACPI_BUTTON_HID_SLEEPF))
385 status =
386 acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
387 acpi_device_notify_fixed,
388 device);
389 else
390 status = acpi_install_notify_handler(device->handle,
391 ACPI_DEVICE_NOTIFY,
392 acpi_device_notify,
393 device);
395 if (ACPI_FAILURE(status))
396 return -EINVAL;
397 return 0;
400 static void acpi_device_remove_notify_handler(struct acpi_device *device)
402 if (!strcmp(acpi_device_hid(device), ACPI_BUTTON_HID_POWERF))
403 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
404 acpi_device_notify_fixed);
405 else if (!strcmp(acpi_device_hid(device), ACPI_BUTTON_HID_SLEEPF))
406 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
407 acpi_device_notify_fixed);
408 else
409 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
410 acpi_device_notify);
413 static int acpi_bus_driver_init(struct acpi_device *, struct acpi_driver *);
414 static int acpi_start_single_object(struct acpi_device *);
415 static int acpi_device_probe(struct device * dev)
417 struct acpi_device *acpi_dev = to_acpi_device(dev);
418 struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
419 int ret;
421 ret = acpi_bus_driver_init(acpi_dev, acpi_drv);
422 if (!ret) {
423 if (acpi_dev->bus_ops.acpi_op_start)
424 acpi_start_single_object(acpi_dev);
426 if (acpi_drv->ops.notify) {
427 ret = acpi_device_install_notify_handler(acpi_dev);
428 if (ret) {
429 if (acpi_drv->ops.stop)
430 acpi_drv->ops.stop(acpi_dev,
431 acpi_dev->removal_type);
432 if (acpi_drv->ops.remove)
433 acpi_drv->ops.remove(acpi_dev,
434 acpi_dev->removal_type);
435 return ret;
439 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
440 "Found driver [%s] for device [%s]\n",
441 acpi_drv->name, acpi_dev->pnp.bus_id));
442 get_device(dev);
444 return ret;
447 static int acpi_device_remove(struct device * dev)
449 struct acpi_device *acpi_dev = to_acpi_device(dev);
450 struct acpi_driver *acpi_drv = acpi_dev->driver;
452 if (acpi_drv) {
453 if (acpi_drv->ops.notify)
454 acpi_device_remove_notify_handler(acpi_dev);
455 if (acpi_drv->ops.stop)
456 acpi_drv->ops.stop(acpi_dev, acpi_dev->removal_type);
457 if (acpi_drv->ops.remove)
458 acpi_drv->ops.remove(acpi_dev, acpi_dev->removal_type);
460 acpi_dev->driver = NULL;
461 acpi_dev->driver_data = NULL;
463 put_device(dev);
464 return 0;
467 struct bus_type acpi_bus_type = {
468 .name = "acpi",
469 .suspend = acpi_device_suspend,
470 .resume = acpi_device_resume,
471 .match = acpi_bus_match,
472 .probe = acpi_device_probe,
473 .remove = acpi_device_remove,
474 .uevent = acpi_device_uevent,
477 static int acpi_device_register(struct acpi_device *device,
478 struct acpi_device *parent)
480 int result;
481 struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
482 int found = 0;
484 * Linkage
485 * -------
486 * Link this device to its parent and siblings.
488 INIT_LIST_HEAD(&device->children);
489 INIT_LIST_HEAD(&device->node);
490 INIT_LIST_HEAD(&device->wakeup_list);
492 new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
493 if (!new_bus_id) {
494 printk(KERN_ERR PREFIX "Memory allocation error\n");
495 return -ENOMEM;
498 mutex_lock(&acpi_device_lock);
500 * Find suitable bus_id and instance number in acpi_bus_id_list
501 * If failed, create one and link it into acpi_bus_id_list
503 list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
504 if(!strcmp(acpi_device_bus_id->bus_id, device->flags.hardware_id? device->pnp.hardware_id : "device")) {
505 acpi_device_bus_id->instance_no ++;
506 found = 1;
507 kfree(new_bus_id);
508 break;
511 if (!found) {
512 acpi_device_bus_id = new_bus_id;
513 strcpy(acpi_device_bus_id->bus_id, device->flags.hardware_id ? device->pnp.hardware_id : "device");
514 acpi_device_bus_id->instance_no = 0;
515 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
517 dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
519 if (device->parent)
520 list_add_tail(&device->node, &device->parent->children);
522 if (device->wakeup.flags.valid)
523 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
524 mutex_unlock(&acpi_device_lock);
526 if (device->parent)
527 device->dev.parent = &parent->dev;
528 device->dev.bus = &acpi_bus_type;
529 device->dev.release = &acpi_device_release;
530 result = device_register(&device->dev);
531 if (result) {
532 dev_err(&device->dev, "Error registering device\n");
533 goto end;
536 result = acpi_device_setup_files(device);
537 if (result)
538 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
539 dev_name(&device->dev));
541 device->removal_type = ACPI_BUS_REMOVAL_NORMAL;
542 return 0;
543 end:
544 mutex_lock(&acpi_device_lock);
545 if (device->parent)
546 list_del(&device->node);
547 list_del(&device->wakeup_list);
548 mutex_unlock(&acpi_device_lock);
549 return result;
552 static void acpi_device_unregister(struct acpi_device *device, int type)
554 mutex_lock(&acpi_device_lock);
555 if (device->parent)
556 list_del(&device->node);
558 list_del(&device->wakeup_list);
559 mutex_unlock(&acpi_device_lock);
561 acpi_detach_data(device->handle, acpi_bus_data_handler);
563 acpi_device_remove_files(device);
564 device_unregister(&device->dev);
567 /* --------------------------------------------------------------------------
568 Driver Management
569 -------------------------------------------------------------------------- */
571 * acpi_bus_driver_init - add a device to a driver
572 * @device: the device to add and initialize
573 * @driver: driver for the device
575 * Used to initialize a device via its device driver. Called whenever a
576 * driver is bound to a device. Invokes the driver's add() ops.
578 static int
579 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
581 int result = 0;
583 if (!device || !driver)
584 return -EINVAL;
586 if (!driver->ops.add)
587 return -ENOSYS;
589 result = driver->ops.add(device);
590 if (result) {
591 device->driver = NULL;
592 device->driver_data = NULL;
593 return result;
596 device->driver = driver;
599 * TBD - Configuration Management: Assign resources to device based
600 * upon possible configuration and currently allocated resources.
603 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
604 "Driver successfully bound to device\n"));
605 return 0;
608 static int acpi_start_single_object(struct acpi_device *device)
610 int result = 0;
611 struct acpi_driver *driver;
614 if (!(driver = device->driver))
615 return 0;
617 if (driver->ops.start) {
618 result = driver->ops.start(device);
619 if (result && driver->ops.remove)
620 driver->ops.remove(device, ACPI_BUS_REMOVAL_NORMAL);
623 return result;
627 * acpi_bus_register_driver - register a driver with the ACPI bus
628 * @driver: driver being registered
630 * Registers a driver with the ACPI bus. Searches the namespace for all
631 * devices that match the driver's criteria and binds. Returns zero for
632 * success or a negative error status for failure.
634 int acpi_bus_register_driver(struct acpi_driver *driver)
636 int ret;
638 if (acpi_disabled)
639 return -ENODEV;
640 driver->drv.name = driver->name;
641 driver->drv.bus = &acpi_bus_type;
642 driver->drv.owner = driver->owner;
644 ret = driver_register(&driver->drv);
645 return ret;
648 EXPORT_SYMBOL(acpi_bus_register_driver);
651 * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
652 * @driver: driver to unregister
654 * Unregisters a driver with the ACPI bus. Searches the namespace for all
655 * devices that match the driver's criteria and unbinds.
657 void acpi_bus_unregister_driver(struct acpi_driver *driver)
659 driver_unregister(&driver->drv);
662 EXPORT_SYMBOL(acpi_bus_unregister_driver);
664 /* --------------------------------------------------------------------------
665 Device Enumeration
666 -------------------------------------------------------------------------- */
667 acpi_status
668 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
670 acpi_status status;
671 acpi_handle tmp;
672 struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
673 union acpi_object *obj;
675 status = acpi_get_handle(handle, "_EJD", &tmp);
676 if (ACPI_FAILURE(status))
677 return status;
679 status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
680 if (ACPI_SUCCESS(status)) {
681 obj = buffer.pointer;
682 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
683 ejd);
684 kfree(buffer.pointer);
686 return status;
688 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
690 void acpi_bus_data_handler(acpi_handle handle, u32 function, void *context)
693 /* TBD */
695 return;
698 static int acpi_bus_get_perf_flags(struct acpi_device *device)
700 device->performance.state = ACPI_STATE_UNKNOWN;
701 return 0;
704 static acpi_status
705 acpi_bus_extract_wakeup_device_power_package(struct acpi_device *device,
706 union acpi_object *package)
708 int i = 0;
709 union acpi_object *element = NULL;
711 if (!device || !package || (package->package.count < 2))
712 return AE_BAD_PARAMETER;
714 element = &(package->package.elements[0]);
715 if (!element)
716 return AE_BAD_PARAMETER;
717 if (element->type == ACPI_TYPE_PACKAGE) {
718 if ((element->package.count < 2) ||
719 (element->package.elements[0].type !=
720 ACPI_TYPE_LOCAL_REFERENCE)
721 || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
722 return AE_BAD_DATA;
723 device->wakeup.gpe_device =
724 element->package.elements[0].reference.handle;
725 device->wakeup.gpe_number =
726 (u32) element->package.elements[1].integer.value;
727 } else if (element->type == ACPI_TYPE_INTEGER) {
728 device->wakeup.gpe_number = element->integer.value;
729 } else
730 return AE_BAD_DATA;
732 element = &(package->package.elements[1]);
733 if (element->type != ACPI_TYPE_INTEGER) {
734 return AE_BAD_DATA;
736 device->wakeup.sleep_state = element->integer.value;
738 if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
739 return AE_NO_MEMORY;
741 device->wakeup.resources.count = package->package.count - 2;
742 for (i = 0; i < device->wakeup.resources.count; i++) {
743 element = &(package->package.elements[i + 2]);
744 if (element->type != ACPI_TYPE_LOCAL_REFERENCE)
745 return AE_BAD_DATA;
747 device->wakeup.resources.handles[i] = element->reference.handle;
750 return AE_OK;
753 static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
755 acpi_status status = 0;
756 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
757 union acpi_object *package = NULL;
758 int psw_error;
760 struct acpi_device_id button_device_ids[] = {
761 {"PNP0C0D", 0},
762 {"PNP0C0C", 0},
763 {"PNP0C0E", 0},
764 {"", 0},
767 /* _PRW */
768 status = acpi_evaluate_object(device->handle, "_PRW", NULL, &buffer);
769 if (ACPI_FAILURE(status)) {
770 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
771 goto end;
774 package = (union acpi_object *)buffer.pointer;
775 status = acpi_bus_extract_wakeup_device_power_package(device, package);
776 if (ACPI_FAILURE(status)) {
777 ACPI_EXCEPTION((AE_INFO, status, "Extracting _PRW package"));
778 goto end;
781 kfree(buffer.pointer);
783 device->wakeup.flags.valid = 1;
784 /* Call _PSW/_DSW object to disable its ability to wake the sleeping
785 * system for the ACPI device with the _PRW object.
786 * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
787 * So it is necessary to call _DSW object first. Only when it is not
788 * present will the _PSW object used.
790 psw_error = acpi_device_sleep_wake(device, 0, 0, 0);
791 if (psw_error)
792 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
793 "error in _DSW or _PSW evaluation\n"));
795 /* Power button, Lid switch always enable wakeup */
796 if (!acpi_match_device_ids(device, button_device_ids))
797 device->wakeup.flags.run_wake = 1;
799 end:
800 if (ACPI_FAILURE(status))
801 device->flags.wake_capable = 0;
802 return 0;
805 static int acpi_bus_get_power_flags(struct acpi_device *device)
807 acpi_status status = 0;
808 acpi_handle handle = NULL;
809 u32 i = 0;
813 * Power Management Flags
815 status = acpi_get_handle(device->handle, "_PSC", &handle);
816 if (ACPI_SUCCESS(status))
817 device->power.flags.explicit_get = 1;
818 status = acpi_get_handle(device->handle, "_IRC", &handle);
819 if (ACPI_SUCCESS(status))
820 device->power.flags.inrush_current = 1;
823 * Enumerate supported power management states
825 for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
826 struct acpi_device_power_state *ps = &device->power.states[i];
827 char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
829 /* Evaluate "_PRx" to se if power resources are referenced */
830 acpi_evaluate_reference(device->handle, object_name, NULL,
831 &ps->resources);
832 if (ps->resources.count) {
833 device->power.flags.power_resources = 1;
834 ps->flags.valid = 1;
837 /* Evaluate "_PSx" to see if we can do explicit sets */
838 object_name[2] = 'S';
839 status = acpi_get_handle(device->handle, object_name, &handle);
840 if (ACPI_SUCCESS(status)) {
841 ps->flags.explicit_set = 1;
842 ps->flags.valid = 1;
845 /* State is valid if we have some power control */
846 if (ps->resources.count || ps->flags.explicit_set)
847 ps->flags.valid = 1;
849 ps->power = -1; /* Unknown - driver assigned */
850 ps->latency = -1; /* Unknown - driver assigned */
853 /* Set defaults for D0 and D3 states (always valid) */
854 device->power.states[ACPI_STATE_D0].flags.valid = 1;
855 device->power.states[ACPI_STATE_D0].power = 100;
856 device->power.states[ACPI_STATE_D3].flags.valid = 1;
857 device->power.states[ACPI_STATE_D3].power = 0;
859 /* TBD: System wake support and resource requirements. */
861 device->power.state = ACPI_STATE_UNKNOWN;
862 acpi_bus_get_power(device->handle, &(device->power.state));
864 return 0;
867 static int acpi_bus_get_flags(struct acpi_device *device)
869 acpi_status status = AE_OK;
870 acpi_handle temp = NULL;
873 /* Presence of _STA indicates 'dynamic_status' */
874 status = acpi_get_handle(device->handle, "_STA", &temp);
875 if (ACPI_SUCCESS(status))
876 device->flags.dynamic_status = 1;
878 /* Presence of _CID indicates 'compatible_ids' */
879 status = acpi_get_handle(device->handle, "_CID", &temp);
880 if (ACPI_SUCCESS(status))
881 device->flags.compatible_ids = 1;
883 /* Presence of _RMV indicates 'removable' */
884 status = acpi_get_handle(device->handle, "_RMV", &temp);
885 if (ACPI_SUCCESS(status))
886 device->flags.removable = 1;
888 /* Presence of _EJD|_EJ0 indicates 'ejectable' */
889 status = acpi_get_handle(device->handle, "_EJD", &temp);
890 if (ACPI_SUCCESS(status))
891 device->flags.ejectable = 1;
892 else {
893 status = acpi_get_handle(device->handle, "_EJ0", &temp);
894 if (ACPI_SUCCESS(status))
895 device->flags.ejectable = 1;
898 /* Presence of _LCK indicates 'lockable' */
899 status = acpi_get_handle(device->handle, "_LCK", &temp);
900 if (ACPI_SUCCESS(status))
901 device->flags.lockable = 1;
903 /* Presence of _PS0|_PR0 indicates 'power manageable' */
904 status = acpi_get_handle(device->handle, "_PS0", &temp);
905 if (ACPI_FAILURE(status))
906 status = acpi_get_handle(device->handle, "_PR0", &temp);
907 if (ACPI_SUCCESS(status))
908 device->flags.power_manageable = 1;
910 /* Presence of _PRW indicates wake capable */
911 status = acpi_get_handle(device->handle, "_PRW", &temp);
912 if (ACPI_SUCCESS(status))
913 device->flags.wake_capable = 1;
915 /* TBD: Performance management */
917 return 0;
920 static void acpi_device_get_busid(struct acpi_device *device,
921 acpi_handle handle, int type)
923 char bus_id[5] = { '?', 0 };
924 struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
925 int i = 0;
928 * Bus ID
929 * ------
930 * The device's Bus ID is simply the object name.
931 * TBD: Shouldn't this value be unique (within the ACPI namespace)?
933 switch (type) {
934 case ACPI_BUS_TYPE_SYSTEM:
935 strcpy(device->pnp.bus_id, "ACPI");
936 break;
937 case ACPI_BUS_TYPE_POWER_BUTTON:
938 strcpy(device->pnp.bus_id, "PWRF");
939 break;
940 case ACPI_BUS_TYPE_SLEEP_BUTTON:
941 strcpy(device->pnp.bus_id, "SLPF");
942 break;
943 default:
944 acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
945 /* Clean up trailing underscores (if any) */
946 for (i = 3; i > 1; i--) {
947 if (bus_id[i] == '_')
948 bus_id[i] = '\0';
949 else
950 break;
952 strcpy(device->pnp.bus_id, bus_id);
953 break;
958 * acpi_bay_match - see if a device is an ejectable driver bay
960 * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
961 * then we can safely call it an ejectable drive bay
963 static int acpi_bay_match(struct acpi_device *device){
964 acpi_status status;
965 acpi_handle handle;
966 acpi_handle tmp;
967 acpi_handle phandle;
969 handle = device->handle;
971 status = acpi_get_handle(handle, "_EJ0", &tmp);
972 if (ACPI_FAILURE(status))
973 return -ENODEV;
975 if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
976 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
977 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
978 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
979 return 0;
981 if (acpi_get_parent(handle, &phandle))
982 return -ENODEV;
984 if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
985 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
986 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
987 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
988 return 0;
990 return -ENODEV;
994 * acpi_dock_match - see if a device has a _DCK method
996 static int acpi_dock_match(struct acpi_device *device)
998 acpi_handle tmp;
999 return acpi_get_handle(device->handle, "_DCK", &tmp);
1002 static void acpi_device_set_id(struct acpi_device *device,
1003 struct acpi_device *parent, acpi_handle handle,
1004 int type)
1006 struct acpi_device_info *info;
1007 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1008 char *hid = NULL;
1009 char *uid = NULL;
1010 struct acpi_compatible_id_list *cid_list = NULL;
1011 const char *cid_add = NULL;
1012 acpi_status status;
1014 switch (type) {
1015 case ACPI_BUS_TYPE_DEVICE:
1016 status = acpi_get_object_info(handle, &buffer);
1017 if (ACPI_FAILURE(status)) {
1018 printk(KERN_ERR PREFIX "%s: Error reading device info\n", __func__);
1019 return;
1022 info = buffer.pointer;
1023 if (info->valid & ACPI_VALID_HID)
1024 hid = info->hardware_id.value;
1025 if (info->valid & ACPI_VALID_UID)
1026 uid = info->unique_id.value;
1027 if (info->valid & ACPI_VALID_CID)
1028 cid_list = &info->compatibility_id;
1029 if (info->valid & ACPI_VALID_ADR) {
1030 device->pnp.bus_address = info->address;
1031 device->flags.bus_address = 1;
1034 /* If we have a video/bay/dock device, add our selfdefined
1035 HID to the CID list. Like that the video/bay/dock drivers
1036 will get autoloaded and the device might still match
1037 against another driver.
1039 if (acpi_is_video_device(device))
1040 cid_add = ACPI_VIDEO_HID;
1041 else if (ACPI_SUCCESS(acpi_bay_match(device)))
1042 cid_add = ACPI_BAY_HID;
1043 else if (ACPI_SUCCESS(acpi_dock_match(device)))
1044 cid_add = ACPI_DOCK_HID;
1046 break;
1047 case ACPI_BUS_TYPE_POWER:
1048 hid = ACPI_POWER_HID;
1049 break;
1050 case ACPI_BUS_TYPE_PROCESSOR:
1051 hid = ACPI_PROCESSOR_OBJECT_HID;
1052 break;
1053 case ACPI_BUS_TYPE_SYSTEM:
1054 hid = ACPI_SYSTEM_HID;
1055 break;
1056 case ACPI_BUS_TYPE_THERMAL:
1057 hid = ACPI_THERMAL_HID;
1058 break;
1059 case ACPI_BUS_TYPE_POWER_BUTTON:
1060 hid = ACPI_BUTTON_HID_POWERF;
1061 break;
1062 case ACPI_BUS_TYPE_SLEEP_BUTTON:
1063 hid = ACPI_BUTTON_HID_SLEEPF;
1064 break;
1068 * \_SB
1069 * ----
1070 * Fix for the system root bus device -- the only root-level device.
1072 if (((acpi_handle)parent == ACPI_ROOT_OBJECT) && (type == ACPI_BUS_TYPE_DEVICE)) {
1073 hid = ACPI_BUS_HID;
1074 strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
1075 strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
1078 if (hid) {
1079 strcpy(device->pnp.hardware_id, hid);
1080 device->flags.hardware_id = 1;
1082 if (uid) {
1083 strcpy(device->pnp.unique_id, uid);
1084 device->flags.unique_id = 1;
1086 if (cid_list || cid_add) {
1087 struct acpi_compatible_id_list *list;
1088 int size = 0;
1089 int count = 0;
1091 if (cid_list) {
1092 size = cid_list->size;
1093 } else if (cid_add) {
1094 size = sizeof(struct acpi_compatible_id_list);
1095 cid_list = ACPI_ALLOCATE_ZEROED((acpi_size) size);
1096 if (!cid_list) {
1097 printk(KERN_ERR "Memory allocation error\n");
1098 kfree(buffer.pointer);
1099 return;
1100 } else {
1101 cid_list->count = 0;
1102 cid_list->size = size;
1105 if (cid_add)
1106 size += sizeof(struct acpi_compatible_id);
1107 list = kmalloc(size, GFP_KERNEL);
1109 if (list) {
1110 if (cid_list) {
1111 memcpy(list, cid_list, cid_list->size);
1112 count = cid_list->count;
1114 if (cid_add) {
1115 strncpy(list->id[count].value, cid_add,
1116 ACPI_MAX_CID_LENGTH);
1117 count++;
1118 device->flags.compatible_ids = 1;
1120 list->size = size;
1121 list->count = count;
1122 device->pnp.cid_list = list;
1123 } else
1124 printk(KERN_ERR PREFIX "Memory allocation error\n");
1127 kfree(buffer.pointer);
1130 static int acpi_device_set_context(struct acpi_device *device, int type)
1132 acpi_status status = AE_OK;
1133 int result = 0;
1135 * Context
1136 * -------
1137 * Attach this 'struct acpi_device' to the ACPI object. This makes
1138 * resolutions from handle->device very efficient. Note that we need
1139 * to be careful with fixed-feature devices as they all attach to the
1140 * root object.
1142 if (type != ACPI_BUS_TYPE_POWER_BUTTON &&
1143 type != ACPI_BUS_TYPE_SLEEP_BUTTON) {
1144 status = acpi_attach_data(device->handle,
1145 acpi_bus_data_handler, device);
1147 if (ACPI_FAILURE(status)) {
1148 printk(KERN_ERR PREFIX "Error attaching device data\n");
1149 result = -ENODEV;
1152 return result;
1155 static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
1157 if (!dev)
1158 return -EINVAL;
1160 dev->removal_type = ACPI_BUS_REMOVAL_EJECT;
1161 device_release_driver(&dev->dev);
1163 if (!rmdevice)
1164 return 0;
1167 * unbind _ADR-Based Devices when hot removal
1169 if (dev->flags.bus_address) {
1170 if ((dev->parent) && (dev->parent->ops.unbind))
1171 dev->parent->ops.unbind(dev);
1173 acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
1175 return 0;
1178 static int
1179 acpi_add_single_object(struct acpi_device **child,
1180 struct acpi_device *parent, acpi_handle handle, int type,
1181 struct acpi_bus_ops *ops)
1183 int result = 0;
1184 struct acpi_device *device = NULL;
1187 if (!child)
1188 return -EINVAL;
1190 device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1191 if (!device) {
1192 printk(KERN_ERR PREFIX "Memory allocation error\n");
1193 return -ENOMEM;
1196 device->handle = handle;
1197 device->parent = parent;
1198 device->bus_ops = *ops; /* workround for not call .start */
1201 acpi_device_get_busid(device, handle, type);
1204 * Flags
1205 * -----
1206 * Get prior to calling acpi_bus_get_status() so we know whether
1207 * or not _STA is present. Note that we only look for object
1208 * handles -- cannot evaluate objects until we know the device is
1209 * present and properly initialized.
1211 result = acpi_bus_get_flags(device);
1212 if (result)
1213 goto end;
1216 * Status
1217 * ------
1218 * See if the device is present. We always assume that non-Device
1219 * and non-Processor objects (e.g. thermal zones, power resources,
1220 * etc.) are present, functioning, etc. (at least when parent object
1221 * is present). Note that _STA has a different meaning for some
1222 * objects (e.g. power resources) so we need to be careful how we use
1223 * it.
1225 switch (type) {
1226 case ACPI_BUS_TYPE_PROCESSOR:
1227 case ACPI_BUS_TYPE_DEVICE:
1228 result = acpi_bus_get_status(device);
1229 if (ACPI_FAILURE(result)) {
1230 result = -ENODEV;
1231 goto end;
1234 * When the device is neither present nor functional, the
1235 * device should not be added to Linux ACPI device tree.
1236 * When the status of the device is not present but functinal,
1237 * it should be added to Linux ACPI tree. For example : bay
1238 * device , dock device.
1239 * In such conditions it is unncessary to check whether it is
1240 * bay device or dock device.
1242 if (!device->status.present && !device->status.functional) {
1243 result = -ENODEV;
1244 goto end;
1246 break;
1247 default:
1248 STRUCT_TO_INT(device->status) =
1249 ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED |
1250 ACPI_STA_DEVICE_UI | ACPI_STA_DEVICE_FUNCTIONING;
1251 break;
1255 * Initialize Device
1256 * -----------------
1257 * TBD: Synch with Core's enumeration/initialization process.
1261 * Hardware ID, Unique ID, & Bus Address
1262 * -------------------------------------
1264 acpi_device_set_id(device, parent, handle, type);
1267 * The ACPI device is attached to acpi handle before getting
1268 * the power/wakeup/peformance flags. Otherwise OS can't get
1269 * the corresponding ACPI device by the acpi handle in the course
1270 * of getting the power/wakeup/performance flags.
1272 result = acpi_device_set_context(device, type);
1273 if (result)
1274 goto end;
1277 * Power Management
1278 * ----------------
1280 if (device->flags.power_manageable) {
1281 result = acpi_bus_get_power_flags(device);
1282 if (result)
1283 goto end;
1287 * Wakeup device management
1288 *-----------------------
1290 if (device->flags.wake_capable) {
1291 result = acpi_bus_get_wakeup_device_flags(device);
1292 if (result)
1293 goto end;
1297 * Performance Management
1298 * ----------------------
1300 if (device->flags.performance_manageable) {
1301 result = acpi_bus_get_perf_flags(device);
1302 if (result)
1303 goto end;
1307 result = acpi_device_register(device, parent);
1310 * Bind _ADR-Based Devices when hot add
1312 if (device->flags.bus_address) {
1313 if (device->parent && device->parent->ops.bind)
1314 device->parent->ops.bind(device);
1317 end:
1318 if (!result)
1319 *child = device;
1320 else {
1321 kfree(device->pnp.cid_list);
1322 kfree(device);
1325 return result;
1328 static int acpi_bus_scan(struct acpi_device *start, struct acpi_bus_ops *ops)
1330 acpi_status status = AE_OK;
1331 struct acpi_device *parent = NULL;
1332 struct acpi_device *child = NULL;
1333 acpi_handle phandle = NULL;
1334 acpi_handle chandle = NULL;
1335 acpi_object_type type = 0;
1336 u32 level = 1;
1339 if (!start)
1340 return -EINVAL;
1342 parent = start;
1343 phandle = start->handle;
1346 * Parse through the ACPI namespace, identify all 'devices', and
1347 * create a new 'struct acpi_device' for each.
1349 while ((level > 0) && parent) {
1351 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1352 chandle, &chandle);
1355 * If this scope is exhausted then move our way back up.
1357 if (ACPI_FAILURE(status)) {
1358 level--;
1359 chandle = phandle;
1360 acpi_get_parent(phandle, &phandle);
1361 if (parent->parent)
1362 parent = parent->parent;
1363 continue;
1366 status = acpi_get_type(chandle, &type);
1367 if (ACPI_FAILURE(status))
1368 continue;
1371 * If this is a scope object then parse it (depth-first).
1373 if (type == ACPI_TYPE_LOCAL_SCOPE) {
1374 level++;
1375 phandle = chandle;
1376 chandle = NULL;
1377 continue;
1381 * We're only interested in objects that we consider 'devices'.
1383 switch (type) {
1384 case ACPI_TYPE_DEVICE:
1385 type = ACPI_BUS_TYPE_DEVICE;
1386 break;
1387 case ACPI_TYPE_PROCESSOR:
1388 type = ACPI_BUS_TYPE_PROCESSOR;
1389 break;
1390 case ACPI_TYPE_THERMAL:
1391 type = ACPI_BUS_TYPE_THERMAL;
1392 break;
1393 case ACPI_TYPE_POWER:
1394 type = ACPI_BUS_TYPE_POWER;
1395 break;
1396 default:
1397 continue;
1400 if (ops->acpi_op_add)
1401 status = acpi_add_single_object(&child, parent,
1402 chandle, type, ops);
1403 else
1404 status = acpi_bus_get_device(chandle, &child);
1406 if (ACPI_FAILURE(status))
1407 continue;
1409 if (ops->acpi_op_start && !(ops->acpi_op_add)) {
1410 status = acpi_start_single_object(child);
1411 if (ACPI_FAILURE(status))
1412 continue;
1416 * If the device is present, enabled, and functioning then
1417 * parse its scope (depth-first). Note that we need to
1418 * represent absent devices to facilitate PnP notifications
1419 * -- but only the subtree head (not all of its children,
1420 * which will be enumerated when the parent is inserted).
1422 * TBD: Need notifications and other detection mechanisms
1423 * in place before we can fully implement this.
1426 * When the device is not present but functional, it is also
1427 * necessary to scan the children of this device.
1429 if (child->status.present || (!child->status.present &&
1430 child->status.functional)) {
1431 status = acpi_get_next_object(ACPI_TYPE_ANY, chandle,
1432 NULL, NULL);
1433 if (ACPI_SUCCESS(status)) {
1434 level++;
1435 phandle = chandle;
1436 chandle = NULL;
1437 parent = child;
1442 return 0;
1446 acpi_bus_add(struct acpi_device **child,
1447 struct acpi_device *parent, acpi_handle handle, int type)
1449 int result;
1450 struct acpi_bus_ops ops;
1452 memset(&ops, 0, sizeof(ops));
1453 ops.acpi_op_add = 1;
1455 result = acpi_add_single_object(child, parent, handle, type, &ops);
1456 if (!result)
1457 result = acpi_bus_scan(*child, &ops);
1459 return result;
1461 EXPORT_SYMBOL(acpi_bus_add);
1463 int acpi_bus_start(struct acpi_device *device)
1465 int result;
1466 struct acpi_bus_ops ops;
1469 if (!device)
1470 return -EINVAL;
1472 result = acpi_start_single_object(device);
1473 if (!result) {
1474 memset(&ops, 0, sizeof(ops));
1475 ops.acpi_op_start = 1;
1476 result = acpi_bus_scan(device, &ops);
1478 return result;
1480 EXPORT_SYMBOL(acpi_bus_start);
1482 int acpi_bus_trim(struct acpi_device *start, int rmdevice)
1484 acpi_status status;
1485 struct acpi_device *parent, *child;
1486 acpi_handle phandle, chandle;
1487 acpi_object_type type;
1488 u32 level = 1;
1489 int err = 0;
1491 parent = start;
1492 phandle = start->handle;
1493 child = chandle = NULL;
1495 while ((level > 0) && parent && (!err)) {
1496 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1497 chandle, &chandle);
1500 * If this scope is exhausted then move our way back up.
1502 if (ACPI_FAILURE(status)) {
1503 level--;
1504 chandle = phandle;
1505 acpi_get_parent(phandle, &phandle);
1506 child = parent;
1507 parent = parent->parent;
1509 if (level == 0)
1510 err = acpi_bus_remove(child, rmdevice);
1511 else
1512 err = acpi_bus_remove(child, 1);
1514 continue;
1517 status = acpi_get_type(chandle, &type);
1518 if (ACPI_FAILURE(status)) {
1519 continue;
1522 * If there is a device corresponding to chandle then
1523 * parse it (depth-first).
1525 if (acpi_bus_get_device(chandle, &child) == 0) {
1526 level++;
1527 phandle = chandle;
1528 chandle = NULL;
1529 parent = child;
1531 continue;
1533 return err;
1535 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1537 static int acpi_bus_scan_fixed(struct acpi_device *root)
1539 int result = 0;
1540 struct acpi_device *device = NULL;
1541 struct acpi_bus_ops ops;
1543 if (!root)
1544 return -ENODEV;
1546 memset(&ops, 0, sizeof(ops));
1547 ops.acpi_op_add = 1;
1548 ops.acpi_op_start = 1;
1551 * Enumerate all fixed-feature devices.
1553 if ((acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON) == 0) {
1554 result = acpi_add_single_object(&device, acpi_root,
1555 NULL,
1556 ACPI_BUS_TYPE_POWER_BUTTON,
1557 &ops);
1560 if ((acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON) == 0) {
1561 result = acpi_add_single_object(&device, acpi_root,
1562 NULL,
1563 ACPI_BUS_TYPE_SLEEP_BUTTON,
1564 &ops);
1567 return result;
1570 int __init acpi_scan_init(void)
1572 int result;
1573 struct acpi_bus_ops ops;
1575 memset(&ops, 0, sizeof(ops));
1576 ops.acpi_op_add = 1;
1577 ops.acpi_op_start = 1;
1579 result = bus_register(&acpi_bus_type);
1580 if (result) {
1581 /* We don't want to quit even if we failed to add suspend/resume */
1582 printk(KERN_ERR PREFIX "Could not register bus type\n");
1586 * Create the root device in the bus's device tree
1588 result = acpi_add_single_object(&acpi_root, NULL, ACPI_ROOT_OBJECT,
1589 ACPI_BUS_TYPE_SYSTEM, &ops);
1590 if (result)
1591 goto Done;
1594 * Enumerate devices in the ACPI namespace.
1596 result = acpi_bus_scan_fixed(acpi_root);
1598 if (!result)
1599 result = acpi_bus_scan(acpi_root, &ops);
1601 if (result)
1602 acpi_device_unregister(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
1604 Done:
1605 return result;