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[kernel/linux-2.6.36.git] / drivers / acpi / scan.c
1 /*
2  * scan.c - support for transforming the ACPI namespace into individual objects
3  */
4
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
14 #include <acpi/acpi_drivers.h>
15
16 #include "internal.h"
17
18 #define _COMPONENT              ACPI_BUS_COMPONENT
19 ACPI_MODULE_NAME("scan");
20 #define STRUCT_TO_INT(s)        (*((int*)&s))
21 extern struct acpi_device *acpi_root;
22
23 #define ACPI_BUS_CLASS                  "system_bus"
24 #define ACPI_BUS_HID                    "LNXSYBUS"
25 #define ACPI_BUS_DEVICE_NAME            "System Bus"
26
27 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
28
29 static LIST_HEAD(acpi_device_list);
30 static LIST_HEAD(acpi_bus_id_list);
31 DEFINE_MUTEX(acpi_device_lock);
32 LIST_HEAD(acpi_wakeup_device_list);
33
34 struct acpi_device_bus_id{
35         char bus_id[15];
36         unsigned int instance_no;
37         struct list_head node;
38 };
39
40 /*
41  * Creates hid/cid(s) string needed for modalias and uevent
42  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
43  * char *modalias: "acpi:IBM0001:ACPI0001"
44 */
45 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
46                            int size)
47 {
48         int len;
49         int count;
50         struct acpi_hardware_id *id;
51
52         len = snprintf(modalias, size, "acpi:");
53         size -= len;
54
55         list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
56                 count = snprintf(&modalias[len], size, "%s:", id->id);
57                 if (count < 0 || count >= size)
58                         return -EINVAL;
59                 len += count;
60                 size -= count;
61         }
62
63         modalias[len] = '\0';
64         return len;
65 }
66
67 static ssize_t
68 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
69         struct acpi_device *acpi_dev = to_acpi_device(dev);
70         int len;
71
72         /* Device has no HID and no CID or string is >1024 */
73         len = create_modalias(acpi_dev, buf, 1024);
74         if (len <= 0)
75                 return 0;
76         buf[len++] = '\n';
77         return len;
78 }
79 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
80
81 static void acpi_bus_hot_remove_device(void *context)
82 {
83         struct acpi_device *device;
84         acpi_handle handle = context;
85         struct acpi_object_list arg_list;
86         union acpi_object arg;
87         acpi_status status = AE_OK;
88
89         if (acpi_bus_get_device(handle, &device))
90                 return;
91
92         if (!device)
93                 return;
94
95         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
96                 "Hot-removing device %s...\n", dev_name(&device->dev)));
97
98         if (acpi_bus_trim(device, 1)) {
99                 printk(KERN_ERR PREFIX
100                                 "Removing device failed\n");
101                 return;
102         }
103
104         /* power off device */
105         status = acpi_evaluate_object(handle, "_PS3", NULL, NULL);
106         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
107                 printk(KERN_WARNING PREFIX
108                                 "Power-off device failed\n");
109
110         if (device->flags.lockable) {
111                 arg_list.count = 1;
112                 arg_list.pointer = &arg;
113                 arg.type = ACPI_TYPE_INTEGER;
114                 arg.integer.value = 0;
115                 acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
116         }
117
118         arg_list.count = 1;
119         arg_list.pointer = &arg;
120         arg.type = ACPI_TYPE_INTEGER;
121         arg.integer.value = 1;
122
123         /*
124          * TBD: _EJD support.
125          */
126         status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
127         if (ACPI_FAILURE(status))
128                 printk(KERN_WARNING PREFIX
129                                 "Eject device failed\n");
130
131         return;
132 }
133
134 static ssize_t
135 acpi_eject_store(struct device *d, struct device_attribute *attr,
136                 const char *buf, size_t count)
137 {
138         int ret = count;
139         acpi_status status;
140         acpi_object_type type = 0;
141         struct acpi_device *acpi_device = to_acpi_device(d);
142
143         if ((!count) || (buf[0] != '1')) {
144                 return -EINVAL;
145         }
146 #ifndef FORCE_EJECT
147         if (acpi_device->driver == NULL) {
148                 ret = -ENODEV;
149                 goto err;
150         }
151 #endif
152         status = acpi_get_type(acpi_device->handle, &type);
153         if (ACPI_FAILURE(status) || (!acpi_device->flags.ejectable)) {
154                 ret = -ENODEV;
155                 goto err;
156         }
157
158         acpi_os_hotplug_execute(acpi_bus_hot_remove_device, acpi_device->handle);
159 err:
160         return ret;
161 }
162
163 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
164
165 static ssize_t
166 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
167         struct acpi_device *acpi_dev = to_acpi_device(dev);
168
169         return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
170 }
171 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
172
173 static ssize_t
174 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
175         struct acpi_device *acpi_dev = to_acpi_device(dev);
176         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
177         int result;
178
179         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
180         if (result)
181                 goto end;
182
183         result = sprintf(buf, "%s\n", (char*)path.pointer);
184         kfree(path.pointer);
185 end:
186         return result;
187 }
188 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
189
190 static int acpi_device_setup_files(struct acpi_device *dev)
191 {
192         acpi_status status;
193         acpi_handle temp;
194         int result = 0;
195
196         /*
197          * Devices gotten from FADT don't have a "path" attribute
198          */
199         if (dev->handle) {
200                 result = device_create_file(&dev->dev, &dev_attr_path);
201                 if (result)
202                         goto end;
203         }
204
205         result = device_create_file(&dev->dev, &dev_attr_hid);
206         if (result)
207                 goto end;
208
209         result = device_create_file(&dev->dev, &dev_attr_modalias);
210         if (result)
211                 goto end;
212
213         /*
214          * If device has _EJ0, 'eject' file is created that is used to trigger
215          * hot-removal function from userland.
216          */
217         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
218         if (ACPI_SUCCESS(status))
219                 result = device_create_file(&dev->dev, &dev_attr_eject);
220 end:
221         return result;
222 }
223
224 static void acpi_device_remove_files(struct acpi_device *dev)
225 {
226         acpi_status status;
227         acpi_handle temp;
228
229         /*
230          * If device has _EJ0, 'eject' file is created that is used to trigger
231          * hot-removal function from userland.
232          */
233         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
234         if (ACPI_SUCCESS(status))
235                 device_remove_file(&dev->dev, &dev_attr_eject);
236
237         device_remove_file(&dev->dev, &dev_attr_modalias);
238         device_remove_file(&dev->dev, &dev_attr_hid);
239         if (dev->handle)
240                 device_remove_file(&dev->dev, &dev_attr_path);
241 }
242 /* --------------------------------------------------------------------------
243                         ACPI Bus operations
244    -------------------------------------------------------------------------- */
245
246 int acpi_match_device_ids(struct acpi_device *device,
247                           const struct acpi_device_id *ids)
248 {
249         const struct acpi_device_id *id;
250         struct acpi_hardware_id *hwid;
251
252         /*
253          * If the device is not present, it is unnecessary to load device
254          * driver for it.
255          */
256         if (!device->status.present)
257                 return -ENODEV;
258
259         for (id = ids; id->id[0]; id++)
260                 list_for_each_entry(hwid, &device->pnp.ids, list)
261                         if (!strcmp((char *) id->id, hwid->id))
262                                 return 0;
263
264         return -ENOENT;
265 }
266 EXPORT_SYMBOL(acpi_match_device_ids);
267
268 static void acpi_free_ids(struct acpi_device *device)
269 {
270         struct acpi_hardware_id *id, *tmp;
271
272         list_for_each_entry_safe(id, tmp, &device->pnp.ids, list) {
273                 kfree(id->id);
274                 kfree(id);
275         }
276 }
277
278 static void acpi_device_release(struct device *dev)
279 {
280         struct acpi_device *acpi_dev = to_acpi_device(dev);
281
282         acpi_free_ids(acpi_dev);
283         kfree(acpi_dev);
284 }
285
286 static int acpi_device_suspend(struct device *dev, pm_message_t state)
287 {
288         struct acpi_device *acpi_dev = to_acpi_device(dev);
289         struct acpi_driver *acpi_drv = acpi_dev->driver;
290
291         if (acpi_drv && acpi_drv->ops.suspend)
292                 return acpi_drv->ops.suspend(acpi_dev, state);
293         return 0;
294 }
295
296 static int acpi_device_resume(struct device *dev)
297 {
298         struct acpi_device *acpi_dev = to_acpi_device(dev);
299         struct acpi_driver *acpi_drv = acpi_dev->driver;
300
301         if (acpi_drv && acpi_drv->ops.resume)
302                 return acpi_drv->ops.resume(acpi_dev);
303         return 0;
304 }
305
306 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
307 {
308         struct acpi_device *acpi_dev = to_acpi_device(dev);
309         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
310
311         return !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
312 }
313
314 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
315 {
316         struct acpi_device *acpi_dev = to_acpi_device(dev);
317         int len;
318
319         if (add_uevent_var(env, "MODALIAS="))
320                 return -ENOMEM;
321         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
322                               sizeof(env->buf) - env->buflen);
323         if (len >= (sizeof(env->buf) - env->buflen))
324                 return -ENOMEM;
325         env->buflen += len;
326         return 0;
327 }
328
329 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
330 {
331         struct acpi_device *device = data;
332
333         device->driver->ops.notify(device, event);
334 }
335
336 static acpi_status acpi_device_notify_fixed(void *data)
337 {
338         struct acpi_device *device = data;
339
340         /* Fixed hardware devices have no handles */
341         acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
342         return AE_OK;
343 }
344
345 static int acpi_device_install_notify_handler(struct acpi_device *device)
346 {
347         acpi_status status;
348
349         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
350                 status =
351                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
352                                                      acpi_device_notify_fixed,
353                                                      device);
354         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
355                 status =
356                     acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
357                                                      acpi_device_notify_fixed,
358                                                      device);
359         else
360                 status = acpi_install_notify_handler(device->handle,
361                                                      ACPI_DEVICE_NOTIFY,
362                                                      acpi_device_notify,
363                                                      device);
364
365         if (ACPI_FAILURE(status))
366                 return -EINVAL;
367         return 0;
368 }
369
370 static void acpi_device_remove_notify_handler(struct acpi_device *device)
371 {
372         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
373                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
374                                                 acpi_device_notify_fixed);
375         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
376                 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
377                                                 acpi_device_notify_fixed);
378         else
379                 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
380                                            acpi_device_notify);
381 }
382
383 static int acpi_bus_driver_init(struct acpi_device *, struct acpi_driver *);
384 static int acpi_start_single_object(struct acpi_device *);
385 static int acpi_device_probe(struct device * dev)
386 {
387         struct acpi_device *acpi_dev = to_acpi_device(dev);
388         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
389         int ret;
390
391         ret = acpi_bus_driver_init(acpi_dev, acpi_drv);
392         if (!ret) {
393                 if (acpi_dev->bus_ops.acpi_op_start)
394                         acpi_start_single_object(acpi_dev);
395
396                 if (acpi_drv->ops.notify) {
397                         ret = acpi_device_install_notify_handler(acpi_dev);
398                         if (ret) {
399                                 if (acpi_drv->ops.remove)
400                                         acpi_drv->ops.remove(acpi_dev,
401                                                      acpi_dev->removal_type);
402                                 return ret;
403                         }
404                 }
405
406                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
407                         "Found driver [%s] for device [%s]\n",
408                         acpi_drv->name, acpi_dev->pnp.bus_id));
409                 get_device(dev);
410         }
411         return ret;
412 }
413
414 static int acpi_device_remove(struct device * dev)
415 {
416         struct acpi_device *acpi_dev = to_acpi_device(dev);
417         struct acpi_driver *acpi_drv = acpi_dev->driver;
418
419         if (acpi_drv) {
420                 if (acpi_drv->ops.notify)
421                         acpi_device_remove_notify_handler(acpi_dev);
422                 if (acpi_drv->ops.remove)
423                         acpi_drv->ops.remove(acpi_dev, acpi_dev->removal_type);
424         }
425         acpi_dev->driver = NULL;
426         acpi_dev->driver_data = NULL;
427
428         put_device(dev);
429         return 0;
430 }
431
432 struct bus_type acpi_bus_type = {
433         .name           = "acpi",
434         .suspend        = acpi_device_suspend,
435         .resume         = acpi_device_resume,
436         .match          = acpi_bus_match,
437         .probe          = acpi_device_probe,
438         .remove         = acpi_device_remove,
439         .uevent         = acpi_device_uevent,
440 };
441
442 static int acpi_device_register(struct acpi_device *device)
443 {
444         int result;
445         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
446         int found = 0;
447
448         /*
449          * Linkage
450          * -------
451          * Link this device to its parent and siblings.
452          */
453         INIT_LIST_HEAD(&device->children);
454         INIT_LIST_HEAD(&device->node);
455         INIT_LIST_HEAD(&device->wakeup_list);
456
457         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
458         if (!new_bus_id) {
459                 printk(KERN_ERR PREFIX "Memory allocation error\n");
460                 return -ENOMEM;
461         }
462
463         mutex_lock(&acpi_device_lock);
464         /*
465          * Find suitable bus_id and instance number in acpi_bus_id_list
466          * If failed, create one and link it into acpi_bus_id_list
467          */
468         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
469                 if (!strcmp(acpi_device_bus_id->bus_id,
470                             acpi_device_hid(device))) {
471                         acpi_device_bus_id->instance_no++;
472                         found = 1;
473                         kfree(new_bus_id);
474                         break;
475                 }
476         }
477         if (!found) {
478                 acpi_device_bus_id = new_bus_id;
479                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
480                 acpi_device_bus_id->instance_no = 0;
481                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
482         }
483         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
484
485         if (device->parent)
486                 list_add_tail(&device->node, &device->parent->children);
487
488         if (device->wakeup.flags.valid)
489                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
490         mutex_unlock(&acpi_device_lock);
491
492         if (device->parent)
493                 device->dev.parent = &device->parent->dev;
494         device->dev.bus = &acpi_bus_type;
495         device->dev.release = &acpi_device_release;
496         result = device_register(&device->dev);
497         if (result) {
498                 dev_err(&device->dev, "Error registering device\n");
499                 goto end;
500         }
501
502         result = acpi_device_setup_files(device);
503         if (result)
504                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
505                        dev_name(&device->dev));
506
507         device->removal_type = ACPI_BUS_REMOVAL_NORMAL;
508         return 0;
509 end:
510         mutex_lock(&acpi_device_lock);
511         if (device->parent)
512                 list_del(&device->node);
513         list_del(&device->wakeup_list);
514         mutex_unlock(&acpi_device_lock);
515         return result;
516 }
517
518 static void acpi_device_unregister(struct acpi_device *device, int type)
519 {
520         mutex_lock(&acpi_device_lock);
521         if (device->parent)
522                 list_del(&device->node);
523
524         list_del(&device->wakeup_list);
525         mutex_unlock(&acpi_device_lock);
526
527         acpi_detach_data(device->handle, acpi_bus_data_handler);
528
529         acpi_device_remove_files(device);
530         device_unregister(&device->dev);
531 }
532
533 /* --------------------------------------------------------------------------
534                                  Driver Management
535    -------------------------------------------------------------------------- */
536 /**
537  * acpi_bus_driver_init - add a device to a driver
538  * @device: the device to add and initialize
539  * @driver: driver for the device
540  *
541  * Used to initialize a device via its device driver.  Called whenever a
542  * driver is bound to a device.  Invokes the driver's add() ops.
543  */
544 static int
545 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
546 {
547         int result = 0;
548
549         if (!device || !driver)
550                 return -EINVAL;
551
552         if (!driver->ops.add)
553                 return -ENOSYS;
554
555         result = driver->ops.add(device);
556         if (result) {
557                 device->driver = NULL;
558                 device->driver_data = NULL;
559                 return result;
560         }
561
562         device->driver = driver;
563
564         /*
565          * TBD - Configuration Management: Assign resources to device based
566          * upon possible configuration and currently allocated resources.
567          */
568
569         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
570                           "Driver successfully bound to device\n"));
571         return 0;
572 }
573
574 static int acpi_start_single_object(struct acpi_device *device)
575 {
576         int result = 0;
577         struct acpi_driver *driver;
578
579
580         if (!(driver = device->driver))
581                 return 0;
582
583         if (driver->ops.start) {
584                 result = driver->ops.start(device);
585                 if (result && driver->ops.remove)
586                         driver->ops.remove(device, ACPI_BUS_REMOVAL_NORMAL);
587         }
588
589         return result;
590 }
591
592 /**
593  * acpi_bus_register_driver - register a driver with the ACPI bus
594  * @driver: driver being registered
595  *
596  * Registers a driver with the ACPI bus.  Searches the namespace for all
597  * devices that match the driver's criteria and binds.  Returns zero for
598  * success or a negative error status for failure.
599  */
600 int acpi_bus_register_driver(struct acpi_driver *driver)
601 {
602         int ret;
603
604         if (acpi_disabled)
605                 return -ENODEV;
606         driver->drv.name = driver->name;
607         driver->drv.bus = &acpi_bus_type;
608         driver->drv.owner = driver->owner;
609
610         ret = driver_register(&driver->drv);
611         return ret;
612 }
613
614 EXPORT_SYMBOL(acpi_bus_register_driver);
615
616 /**
617  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
618  * @driver: driver to unregister
619  *
620  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
621  * devices that match the driver's criteria and unbinds.
622  */
623 void acpi_bus_unregister_driver(struct acpi_driver *driver)
624 {
625         driver_unregister(&driver->drv);
626 }
627
628 EXPORT_SYMBOL(acpi_bus_unregister_driver);
629
630 /* --------------------------------------------------------------------------
631                                  Device Enumeration
632    -------------------------------------------------------------------------- */
633 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
634 {
635         acpi_status status;
636         int ret;
637         struct acpi_device *device;
638
639         /*
640          * Fixed hardware devices do not appear in the namespace and do not
641          * have handles, but we fabricate acpi_devices for them, so we have
642          * to deal with them specially.
643          */
644         if (handle == NULL)
645                 return acpi_root;
646
647         do {
648                 status = acpi_get_parent(handle, &handle);
649                 if (status == AE_NULL_ENTRY)
650                         return NULL;
651                 if (ACPI_FAILURE(status))
652                         return acpi_root;
653
654                 ret = acpi_bus_get_device(handle, &device);
655                 if (ret == 0)
656                         return device;
657         } while (1);
658 }
659
660 acpi_status
661 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
662 {
663         acpi_status status;
664         acpi_handle tmp;
665         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
666         union acpi_object *obj;
667
668         status = acpi_get_handle(handle, "_EJD", &tmp);
669         if (ACPI_FAILURE(status))
670                 return status;
671
672         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
673         if (ACPI_SUCCESS(status)) {
674                 obj = buffer.pointer;
675                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
676                                          ejd);
677                 kfree(buffer.pointer);
678         }
679         return status;
680 }
681 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
682
683 void acpi_bus_data_handler(acpi_handle handle, void *context)
684 {
685
686         /* TBD */
687
688         return;
689 }
690
691 static int acpi_bus_get_perf_flags(struct acpi_device *device)
692 {
693         device->performance.state = ACPI_STATE_UNKNOWN;
694         return 0;
695 }
696
697 static acpi_status
698 acpi_bus_extract_wakeup_device_power_package(struct acpi_device *device,
699                                              union acpi_object *package)
700 {
701         int i = 0;
702         union acpi_object *element = NULL;
703
704         if (!device || !package || (package->package.count < 2))
705                 return AE_BAD_PARAMETER;
706
707         element = &(package->package.elements[0]);
708         if (!element)
709                 return AE_BAD_PARAMETER;
710         if (element->type == ACPI_TYPE_PACKAGE) {
711                 if ((element->package.count < 2) ||
712                     (element->package.elements[0].type !=
713                      ACPI_TYPE_LOCAL_REFERENCE)
714                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
715                         return AE_BAD_DATA;
716                 device->wakeup.gpe_device =
717                     element->package.elements[0].reference.handle;
718                 device->wakeup.gpe_number =
719                     (u32) element->package.elements[1].integer.value;
720         } else if (element->type == ACPI_TYPE_INTEGER) {
721                 device->wakeup.gpe_number = element->integer.value;
722         } else
723                 return AE_BAD_DATA;
724
725         element = &(package->package.elements[1]);
726         if (element->type != ACPI_TYPE_INTEGER) {
727                 return AE_BAD_DATA;
728         }
729         device->wakeup.sleep_state = element->integer.value;
730
731         if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
732                 return AE_NO_MEMORY;
733         }
734         device->wakeup.resources.count = package->package.count - 2;
735         for (i = 0; i < device->wakeup.resources.count; i++) {
736                 element = &(package->package.elements[i + 2]);
737                 if (element->type != ACPI_TYPE_LOCAL_REFERENCE)
738                         return AE_BAD_DATA;
739
740                 device->wakeup.resources.handles[i] = element->reference.handle;
741         }
742
743         acpi_gpe_can_wake(device->wakeup.gpe_device, device->wakeup.gpe_number);
744
745         return AE_OK;
746 }
747
748 static void acpi_bus_set_run_wake_flags(struct acpi_device *device)
749 {
750         struct acpi_device_id button_device_ids[] = {
751                 {"PNP0C0D", 0},
752                 {"PNP0C0C", 0},
753                 {"PNP0C0E", 0},
754                 {"", 0},
755         };
756         acpi_status status;
757         acpi_event_status event_status;
758
759         device->wakeup.run_wake_count = 0;
760         device->wakeup.flags.notifier_present = 0;
761
762         /* Power button, Lid switch always enable wakeup */
763         if (!acpi_match_device_ids(device, button_device_ids)) {
764                 device->wakeup.flags.run_wake = 1;
765                 device->wakeup.flags.always_enabled = 1;
766                 return;
767         }
768
769         status = acpi_get_gpe_status(device->wakeup.gpe_device,
770                                         device->wakeup.gpe_number,
771                                                 &event_status);
772         if (status == AE_OK)
773                 device->wakeup.flags.run_wake =
774                                 !!(event_status & ACPI_EVENT_FLAG_HANDLE);
775 }
776
777 static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
778 {
779         acpi_status status = 0;
780         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
781         union acpi_object *package = NULL;
782         int psw_error;
783
784         /* _PRW */
785         status = acpi_evaluate_object(device->handle, "_PRW", NULL, &buffer);
786         if (ACPI_FAILURE(status)) {
787                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
788                 goto end;
789         }
790
791         package = (union acpi_object *)buffer.pointer;
792         status = acpi_bus_extract_wakeup_device_power_package(device, package);
793         if (ACPI_FAILURE(status)) {
794                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _PRW package"));
795                 goto end;
796         }
797
798         kfree(buffer.pointer);
799
800         device->wakeup.flags.valid = 1;
801         device->wakeup.prepare_count = 0;
802         acpi_bus_set_run_wake_flags(device);
803         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
804          * system for the ACPI device with the _PRW object.
805          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
806          * So it is necessary to call _DSW object first. Only when it is not
807          * present will the _PSW object used.
808          */
809         psw_error = acpi_device_sleep_wake(device, 0, 0, 0);
810         if (psw_error)
811                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
812                                 "error in _DSW or _PSW evaluation\n"));
813
814 end:
815         if (ACPI_FAILURE(status))
816                 device->flags.wake_capable = 0;
817         return 0;
818 }
819
820 static int acpi_bus_get_power_flags(struct acpi_device *device)
821 {
822         acpi_status status = 0;
823         acpi_handle handle = NULL;
824         u32 i = 0;
825
826
827         /*
828          * Power Management Flags
829          */
830         status = acpi_get_handle(device->handle, "_PSC", &handle);
831         if (ACPI_SUCCESS(status))
832                 device->power.flags.explicit_get = 1;
833         status = acpi_get_handle(device->handle, "_IRC", &handle);
834         if (ACPI_SUCCESS(status))
835                 device->power.flags.inrush_current = 1;
836
837         /*
838          * Enumerate supported power management states
839          */
840         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
841                 struct acpi_device_power_state *ps = &device->power.states[i];
842                 char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
843
844                 /* Evaluate "_PRx" to se if power resources are referenced */
845                 acpi_evaluate_reference(device->handle, object_name, NULL,
846                                         &ps->resources);
847                 if (ps->resources.count) {
848                         device->power.flags.power_resources = 1;
849                         ps->flags.valid = 1;
850                 }
851
852                 /* Evaluate "_PSx" to see if we can do explicit sets */
853                 object_name[2] = 'S';
854                 status = acpi_get_handle(device->handle, object_name, &handle);
855                 if (ACPI_SUCCESS(status)) {
856                         ps->flags.explicit_set = 1;
857                         ps->flags.valid = 1;
858                 }
859
860                 /* State is valid if we have some power control */
861                 if (ps->resources.count || ps->flags.explicit_set)
862                         ps->flags.valid = 1;
863
864                 ps->power = -1; /* Unknown - driver assigned */
865                 ps->latency = -1;       /* Unknown - driver assigned */
866         }
867
868         /* Set defaults for D0 and D3 states (always valid) */
869         device->power.states[ACPI_STATE_D0].flags.valid = 1;
870         device->power.states[ACPI_STATE_D0].power = 100;
871         device->power.states[ACPI_STATE_D3].flags.valid = 1;
872         device->power.states[ACPI_STATE_D3].power = 0;
873
874         /* TBD: System wake support and resource requirements. */
875
876         device->power.state = ACPI_STATE_UNKNOWN;
877         acpi_bus_get_power(device->handle, &(device->power.state));
878
879         return 0;
880 }
881
882 static int acpi_bus_get_flags(struct acpi_device *device)
883 {
884         acpi_status status = AE_OK;
885         acpi_handle temp = NULL;
886
887
888         /* Presence of _STA indicates 'dynamic_status' */
889         status = acpi_get_handle(device->handle, "_STA", &temp);
890         if (ACPI_SUCCESS(status))
891                 device->flags.dynamic_status = 1;
892
893         /* Presence of _RMV indicates 'removable' */
894         status = acpi_get_handle(device->handle, "_RMV", &temp);
895         if (ACPI_SUCCESS(status))
896                 device->flags.removable = 1;
897
898         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
899         status = acpi_get_handle(device->handle, "_EJD", &temp);
900         if (ACPI_SUCCESS(status))
901                 device->flags.ejectable = 1;
902         else {
903                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
904                 if (ACPI_SUCCESS(status))
905                         device->flags.ejectable = 1;
906         }
907
908         /* Presence of _LCK indicates 'lockable' */
909         status = acpi_get_handle(device->handle, "_LCK", &temp);
910         if (ACPI_SUCCESS(status))
911                 device->flags.lockable = 1;
912
913         /* Presence of _PS0|_PR0 indicates 'power manageable' */
914         status = acpi_get_handle(device->handle, "_PS0", &temp);
915         if (ACPI_FAILURE(status))
916                 status = acpi_get_handle(device->handle, "_PR0", &temp);
917         if (ACPI_SUCCESS(status))
918                 device->flags.power_manageable = 1;
919
920         /* Presence of _PRW indicates wake capable */
921         status = acpi_get_handle(device->handle, "_PRW", &temp);
922         if (ACPI_SUCCESS(status))
923                 device->flags.wake_capable = 1;
924
925         /* TBD: Performance management */
926
927         return 0;
928 }
929
930 static void acpi_device_get_busid(struct acpi_device *device)
931 {
932         char bus_id[5] = { '?', 0 };
933         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
934         int i = 0;
935
936         /*
937          * Bus ID
938          * ------
939          * The device's Bus ID is simply the object name.
940          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
941          */
942         if (ACPI_IS_ROOT_DEVICE(device)) {
943                 strcpy(device->pnp.bus_id, "ACPI");
944                 return;
945         }
946
947         switch (device->device_type) {
948         case ACPI_BUS_TYPE_POWER_BUTTON:
949                 strcpy(device->pnp.bus_id, "PWRF");
950                 break;
951         case ACPI_BUS_TYPE_SLEEP_BUTTON:
952                 strcpy(device->pnp.bus_id, "SLPF");
953                 break;
954         default:
955                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
956                 /* Clean up trailing underscores (if any) */
957                 for (i = 3; i > 1; i--) {
958                         if (bus_id[i] == '_')
959                                 bus_id[i] = '\0';
960                         else
961                                 break;
962                 }
963                 strcpy(device->pnp.bus_id, bus_id);
964                 break;
965         }
966 }
967
968 /*
969  * acpi_bay_match - see if a device is an ejectable driver bay
970  *
971  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
972  * then we can safely call it an ejectable drive bay
973  */
974 static int acpi_bay_match(struct acpi_device *device){
975         acpi_status status;
976         acpi_handle handle;
977         acpi_handle tmp;
978         acpi_handle phandle;
979
980         handle = device->handle;
981
982         status = acpi_get_handle(handle, "_EJ0", &tmp);
983         if (ACPI_FAILURE(status))
984                 return -ENODEV;
985
986         if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
987                 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
988                 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
989                 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
990                 return 0;
991
992         if (acpi_get_parent(handle, &phandle))
993                 return -ENODEV;
994
995         if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
996                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
997                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
998                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
999                 return 0;
1000
1001         return -ENODEV;
1002 }
1003
1004 /*
1005  * acpi_dock_match - see if a device has a _DCK method
1006  */
1007 static int acpi_dock_match(struct acpi_device *device)
1008 {
1009         acpi_handle tmp;
1010         return acpi_get_handle(device->handle, "_DCK", &tmp);
1011 }
1012
1013 char *acpi_device_hid(struct acpi_device *device)
1014 {
1015         struct acpi_hardware_id *hid;
1016
1017         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1018         return hid->id;
1019 }
1020 EXPORT_SYMBOL(acpi_device_hid);
1021
1022 static void acpi_add_id(struct acpi_device *device, const char *dev_id)
1023 {
1024         struct acpi_hardware_id *id;
1025
1026         id = kmalloc(sizeof(*id), GFP_KERNEL);
1027         if (!id)
1028                 return;
1029
1030         id->id = kmalloc(strlen(dev_id) + 1, GFP_KERNEL);
1031         if (!id->id) {
1032                 kfree(id);
1033                 return;
1034         }
1035
1036         strcpy(id->id, dev_id);
1037         list_add_tail(&id->list, &device->pnp.ids);
1038 }
1039
1040 /*
1041  * Old IBM workstations have a DSDT bug wherein the SMBus object
1042  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1043  * prefix.  Work around this.
1044  */
1045 static int acpi_ibm_smbus_match(struct acpi_device *device)
1046 {
1047         acpi_handle h_dummy;
1048         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
1049         int result;
1050
1051         if (!dmi_name_in_vendors("IBM"))
1052                 return -ENODEV;
1053
1054         /* Look for SMBS object */
1055         result = acpi_get_name(device->handle, ACPI_SINGLE_NAME, &path);
1056         if (result)
1057                 return result;
1058
1059         if (strcmp("SMBS", path.pointer)) {
1060                 result = -ENODEV;
1061                 goto out;
1062         }
1063
1064         /* Does it have the necessary (but misnamed) methods? */
1065         result = -ENODEV;
1066         if (ACPI_SUCCESS(acpi_get_handle(device->handle, "SBI", &h_dummy)) &&
1067             ACPI_SUCCESS(acpi_get_handle(device->handle, "SBR", &h_dummy)) &&
1068             ACPI_SUCCESS(acpi_get_handle(device->handle, "SBW", &h_dummy)))
1069                 result = 0;
1070 out:
1071         kfree(path.pointer);
1072         return result;
1073 }
1074
1075 static void acpi_device_set_id(struct acpi_device *device)
1076 {
1077         acpi_status status;
1078         struct acpi_device_info *info;
1079         struct acpica_device_id_list *cid_list;
1080         int i;
1081
1082         switch (device->device_type) {
1083         case ACPI_BUS_TYPE_DEVICE:
1084                 if (ACPI_IS_ROOT_DEVICE(device)) {
1085                         acpi_add_id(device, ACPI_SYSTEM_HID);
1086                         break;
1087                 }
1088
1089                 status = acpi_get_object_info(device->handle, &info);
1090                 if (ACPI_FAILURE(status)) {
1091                         printk(KERN_ERR PREFIX "%s: Error reading device info\n", __func__);
1092                         return;
1093                 }
1094
1095                 if (info->valid & ACPI_VALID_HID)
1096                         acpi_add_id(device, info->hardware_id.string);
1097                 if (info->valid & ACPI_VALID_CID) {
1098                         cid_list = &info->compatible_id_list;
1099                         for (i = 0; i < cid_list->count; i++)
1100                                 acpi_add_id(device, cid_list->ids[i].string);
1101                 }
1102                 if (info->valid & ACPI_VALID_ADR) {
1103                         device->pnp.bus_address = info->address;
1104                         device->flags.bus_address = 1;
1105                 }
1106
1107                 kfree(info);
1108
1109                 /*
1110                  * Some devices don't reliably have _HIDs & _CIDs, so add
1111                  * synthetic HIDs to make sure drivers can find them.
1112                  */
1113                 if (acpi_is_video_device(device))
1114                         acpi_add_id(device, ACPI_VIDEO_HID);
1115                 else if (ACPI_SUCCESS(acpi_bay_match(device)))
1116                         acpi_add_id(device, ACPI_BAY_HID);
1117                 else if (ACPI_SUCCESS(acpi_dock_match(device)))
1118                         acpi_add_id(device, ACPI_DOCK_HID);
1119                 else if (!acpi_ibm_smbus_match(device))
1120                         acpi_add_id(device, ACPI_SMBUS_IBM_HID);
1121                 else if (!acpi_device_hid(device) &&
1122                          ACPI_IS_ROOT_DEVICE(device->parent)) {
1123                         acpi_add_id(device, ACPI_BUS_HID); /* \_SB, LNXSYBUS */
1124                         strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
1125                         strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
1126                 }
1127
1128                 break;
1129         case ACPI_BUS_TYPE_POWER:
1130                 acpi_add_id(device, ACPI_POWER_HID);
1131                 break;
1132         case ACPI_BUS_TYPE_PROCESSOR:
1133                 acpi_add_id(device, ACPI_PROCESSOR_OBJECT_HID);
1134                 break;
1135         case ACPI_BUS_TYPE_THERMAL:
1136                 acpi_add_id(device, ACPI_THERMAL_HID);
1137                 break;
1138         case ACPI_BUS_TYPE_POWER_BUTTON:
1139                 acpi_add_id(device, ACPI_BUTTON_HID_POWERF);
1140                 break;
1141         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1142                 acpi_add_id(device, ACPI_BUTTON_HID_SLEEPF);
1143                 break;
1144         }
1145
1146         /*
1147          * We build acpi_devices for some objects that don't have _HID or _CID,
1148          * e.g., PCI bridges and slots.  Drivers can't bind to these objects,
1149          * but we do use them indirectly by traversing the acpi_device tree.
1150          * This generic ID isn't useful for driver binding, but it provides
1151          * the useful property that "every acpi_device has an ID."
1152          */
1153         if (list_empty(&device->pnp.ids))
1154                 acpi_add_id(device, "device");
1155 }
1156
1157 static int acpi_device_set_context(struct acpi_device *device)
1158 {
1159         acpi_status status;
1160
1161         /*
1162          * Context
1163          * -------
1164          * Attach this 'struct acpi_device' to the ACPI object.  This makes
1165          * resolutions from handle->device very efficient.  Fixed hardware
1166          * devices have no handles, so we skip them.
1167          */
1168         if (!device->handle)
1169                 return 0;
1170
1171         status = acpi_attach_data(device->handle,
1172                                   acpi_bus_data_handler, device);
1173         if (ACPI_SUCCESS(status))
1174                 return 0;
1175
1176         printk(KERN_ERR PREFIX "Error attaching device data\n");
1177         return -ENODEV;
1178 }
1179
1180 static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
1181 {
1182         if (!dev)
1183                 return -EINVAL;
1184
1185         dev->removal_type = ACPI_BUS_REMOVAL_EJECT;
1186         device_release_driver(&dev->dev);
1187
1188         if (!rmdevice)
1189                 return 0;
1190
1191         /*
1192          * unbind _ADR-Based Devices when hot removal
1193          */
1194         if (dev->flags.bus_address) {
1195                 if ((dev->parent) && (dev->parent->ops.unbind))
1196                         dev->parent->ops.unbind(dev);
1197         }
1198         acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
1199
1200         return 0;
1201 }
1202
1203 static int acpi_add_single_object(struct acpi_device **child,
1204                                   acpi_handle handle, int type,
1205                                   unsigned long long sta,
1206                                   struct acpi_bus_ops *ops)
1207 {
1208         int result;
1209         struct acpi_device *device;
1210         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1211
1212         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1213         if (!device) {
1214                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1215                 return -ENOMEM;
1216         }
1217
1218         INIT_LIST_HEAD(&device->pnp.ids);
1219         device->device_type = type;
1220         device->handle = handle;
1221         device->parent = acpi_bus_get_parent(handle);
1222         device->bus_ops = *ops; /* workround for not call .start */
1223         STRUCT_TO_INT(device->status) = sta;
1224
1225         acpi_device_get_busid(device);
1226
1227         /*
1228          * Flags
1229          * -----
1230          * Note that we only look for object handles -- cannot evaluate objects
1231          * until we know the device is present and properly initialized.
1232          */
1233         result = acpi_bus_get_flags(device);
1234         if (result)
1235                 goto end;
1236
1237         /*
1238          * Initialize Device
1239          * -----------------
1240          * TBD: Synch with Core's enumeration/initialization process.
1241          */
1242         acpi_device_set_id(device);
1243
1244         /*
1245          * Power Management
1246          * ----------------
1247          */
1248         if (device->flags.power_manageable) {
1249                 result = acpi_bus_get_power_flags(device);
1250                 if (result)
1251                         goto end;
1252         }
1253
1254         /*
1255          * Wakeup device management
1256          *-----------------------
1257          */
1258         if (device->flags.wake_capable) {
1259                 result = acpi_bus_get_wakeup_device_flags(device);
1260                 if (result)
1261                         goto end;
1262         }
1263
1264         /*
1265          * Performance Management
1266          * ----------------------
1267          */
1268         if (device->flags.performance_manageable) {
1269                 result = acpi_bus_get_perf_flags(device);
1270                 if (result)
1271                         goto end;
1272         }
1273
1274         if ((result = acpi_device_set_context(device)))
1275                 goto end;
1276
1277         result = acpi_device_register(device);
1278
1279         /*
1280          * Bind _ADR-Based Devices when hot add
1281          */
1282         if (device->flags.bus_address) {
1283                 if (device->parent && device->parent->ops.bind)
1284                         device->parent->ops.bind(device);
1285         }
1286
1287 end:
1288         if (!result) {
1289                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1290                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1291                         "Adding %s [%s] parent %s\n", dev_name(&device->dev),
1292                          (char *) buffer.pointer,
1293                          device->parent ? dev_name(&device->parent->dev) :
1294                                           "(null)"));
1295                 kfree(buffer.pointer);
1296                 *child = device;
1297         } else
1298                 acpi_device_release(&device->dev);
1299
1300         return result;
1301 }
1302
1303 #define ACPI_STA_DEFAULT (ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED | \
1304                           ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING)
1305
1306 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1307                                     unsigned long long *sta)
1308 {
1309         acpi_status status;
1310         acpi_object_type acpi_type;
1311
1312         status = acpi_get_type(handle, &acpi_type);
1313         if (ACPI_FAILURE(status))
1314                 return -ENODEV;
1315
1316         switch (acpi_type) {
1317         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1318         case ACPI_TYPE_DEVICE:
1319                 *type = ACPI_BUS_TYPE_DEVICE;
1320                 status = acpi_bus_get_status_handle(handle, sta);
1321                 if (ACPI_FAILURE(status))
1322                         return -ENODEV;
1323                 break;
1324         case ACPI_TYPE_PROCESSOR:
1325                 *type = ACPI_BUS_TYPE_PROCESSOR;
1326                 status = acpi_bus_get_status_handle(handle, sta);
1327                 if (ACPI_FAILURE(status))
1328                         return -ENODEV;
1329                 break;
1330         case ACPI_TYPE_THERMAL:
1331                 *type = ACPI_BUS_TYPE_THERMAL;
1332                 *sta = ACPI_STA_DEFAULT;
1333                 break;
1334         case ACPI_TYPE_POWER:
1335                 *type = ACPI_BUS_TYPE_POWER;
1336                 *sta = ACPI_STA_DEFAULT;
1337                 break;
1338         default:
1339                 return -ENODEV;
1340         }
1341
1342         return 0;
1343 }
1344
1345 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl,
1346                                       void *context, void **return_value)
1347 {
1348         struct acpi_bus_ops *ops = context;
1349         int type;
1350         unsigned long long sta;
1351         struct acpi_device *device;
1352         acpi_status status;
1353         int result;
1354
1355         result = acpi_bus_type_and_status(handle, &type, &sta);
1356         if (result)
1357                 return AE_OK;
1358
1359         if (!(sta & ACPI_STA_DEVICE_PRESENT) &&
1360             !(sta & ACPI_STA_DEVICE_FUNCTIONING))
1361                 return AE_CTRL_DEPTH;
1362
1363         /*
1364          * We may already have an acpi_device from a previous enumeration.  If
1365          * so, we needn't add it again, but we may still have to start it.
1366          */
1367         device = NULL;
1368         acpi_bus_get_device(handle, &device);
1369         if (ops->acpi_op_add && !device)
1370                 acpi_add_single_object(&device, handle, type, sta, ops);
1371
1372         if (!device)
1373                 return AE_CTRL_DEPTH;
1374
1375         if (ops->acpi_op_start && !(ops->acpi_op_add)) {
1376                 status = acpi_start_single_object(device);
1377                 if (ACPI_FAILURE(status))
1378                         return AE_CTRL_DEPTH;
1379         }
1380
1381         if (!*return_value)
1382                 *return_value = device;
1383         return AE_OK;
1384 }
1385
1386 static int acpi_bus_scan(acpi_handle handle, struct acpi_bus_ops *ops,
1387                          struct acpi_device **child)
1388 {
1389         acpi_status status;
1390         void *device = NULL;
1391
1392         status = acpi_bus_check_add(handle, 0, ops, &device);
1393         if (ACPI_SUCCESS(status))
1394                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1395                                     acpi_bus_check_add, NULL, ops, &device);
1396
1397         if (child)
1398                 *child = device;
1399
1400         if (device)
1401                 return 0;
1402         else
1403                 return -ENODEV;
1404 }
1405
1406 /*
1407  * acpi_bus_add and acpi_bus_start
1408  *
1409  * scan a given ACPI tree and (probably recently hot-plugged)
1410  * create and add or starts found devices.
1411  *
1412  * If no devices were found -ENODEV is returned which does not
1413  * mean that this is a real error, there just have been no suitable
1414  * ACPI objects in the table trunk from which the kernel could create
1415  * a device and add/start an appropriate driver.
1416  */
1417
1418 int
1419 acpi_bus_add(struct acpi_device **child,
1420              struct acpi_device *parent, acpi_handle handle, int type)
1421 {
1422         struct acpi_bus_ops ops;
1423
1424         memset(&ops, 0, sizeof(ops));
1425         ops.acpi_op_add = 1;
1426
1427         return acpi_bus_scan(handle, &ops, child);
1428 }
1429 EXPORT_SYMBOL(acpi_bus_add);
1430
1431 int acpi_bus_start(struct acpi_device *device)
1432 {
1433         struct acpi_bus_ops ops;
1434
1435         if (!device)
1436                 return -EINVAL;
1437
1438         memset(&ops, 0, sizeof(ops));
1439         ops.acpi_op_start = 1;
1440
1441         return acpi_bus_scan(device->handle, &ops, NULL);
1442 }
1443 EXPORT_SYMBOL(acpi_bus_start);
1444
1445 int acpi_bus_trim(struct acpi_device *start, int rmdevice)
1446 {
1447         acpi_status status;
1448         struct acpi_device *parent, *child;
1449         acpi_handle phandle, chandle;
1450         acpi_object_type type;
1451         u32 level = 1;
1452         int err = 0;
1453
1454         parent = start;
1455         phandle = start->handle;
1456         child = chandle = NULL;
1457
1458         while ((level > 0) && parent && (!err)) {
1459                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1460                                               chandle, &chandle);
1461
1462                 /*
1463                  * If this scope is exhausted then move our way back up.
1464                  */
1465                 if (ACPI_FAILURE(status)) {
1466                         level--;
1467                         chandle = phandle;
1468                         acpi_get_parent(phandle, &phandle);
1469                         child = parent;
1470                         parent = parent->parent;
1471
1472                         if (level == 0)
1473                                 err = acpi_bus_remove(child, rmdevice);
1474                         else
1475                                 err = acpi_bus_remove(child, 1);
1476
1477                         continue;
1478                 }
1479
1480                 status = acpi_get_type(chandle, &type);
1481                 if (ACPI_FAILURE(status)) {
1482                         continue;
1483                 }
1484                 /*
1485                  * If there is a device corresponding to chandle then
1486                  * parse it (depth-first).
1487                  */
1488                 if (acpi_bus_get_device(chandle, &child) == 0) {
1489                         level++;
1490                         phandle = chandle;
1491                         chandle = NULL;
1492                         parent = child;
1493                 }
1494                 continue;
1495         }
1496         return err;
1497 }
1498 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1499
1500 static int acpi_bus_scan_fixed(void)
1501 {
1502         int result = 0;
1503         struct acpi_device *device = NULL;
1504         struct acpi_bus_ops ops;
1505
1506         memset(&ops, 0, sizeof(ops));
1507         ops.acpi_op_add = 1;
1508         ops.acpi_op_start = 1;
1509
1510         /*
1511          * Enumerate all fixed-feature devices.
1512          */
1513         if ((acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON) == 0) {
1514                 result = acpi_add_single_object(&device, NULL,
1515                                                 ACPI_BUS_TYPE_POWER_BUTTON,
1516                                                 ACPI_STA_DEFAULT,
1517                                                 &ops);
1518         }
1519
1520         if ((acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON) == 0) {
1521                 result = acpi_add_single_object(&device, NULL,
1522                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
1523                                                 ACPI_STA_DEFAULT,
1524                                                 &ops);
1525         }
1526
1527         return result;
1528 }
1529
1530 int __init acpi_scan_init(void)
1531 {
1532         int result;
1533         struct acpi_bus_ops ops;
1534
1535         memset(&ops, 0, sizeof(ops));
1536         ops.acpi_op_add = 1;
1537         ops.acpi_op_start = 1;
1538
1539         result = bus_register(&acpi_bus_type);
1540         if (result) {
1541                 /* We don't want to quit even if we failed to add suspend/resume */
1542                 printk(KERN_ERR PREFIX "Could not register bus type\n");
1543         }
1544
1545         /*
1546          * Enumerate devices in the ACPI namespace.
1547          */
1548         result = acpi_bus_scan(ACPI_ROOT_OBJECT, &ops, &acpi_root);
1549
1550         if (!result)
1551                 result = acpi_bus_scan_fixed();
1552
1553         if (result)
1554                 acpi_device_unregister(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
1555
1556         return result;
1557 }