Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
[pandora-kernel.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 const char *dummy_hid = "device";
30
31 static LIST_HEAD(acpi_device_list);
32 static LIST_HEAD(acpi_bus_id_list);
33 DEFINE_MUTEX(acpi_device_lock);
34 LIST_HEAD(acpi_wakeup_device_list);
35
36 struct acpi_device_bus_id{
37         char bus_id[15];
38         unsigned int instance_no;
39         struct list_head node;
40 };
41
42 /*
43  * Creates hid/cid(s) string needed for modalias and uevent
44  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
45  * char *modalias: "acpi:IBM0001:ACPI0001"
46 */
47 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
48                            int size)
49 {
50         int len;
51         int count;
52         struct acpi_hardware_id *id;
53
54         if (list_empty(&acpi_dev->pnp.ids))
55                 return 0;
56
57         len = snprintf(modalias, size, "acpi:");
58         size -= len;
59
60         list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
61                 count = snprintf(&modalias[len], size, "%s:", id->id);
62                 if (count < 0 || count >= size)
63                         return -EINVAL;
64                 len += count;
65                 size -= count;
66         }
67
68         modalias[len] = '\0';
69         return len;
70 }
71
72 static ssize_t
73 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
74         struct acpi_device *acpi_dev = to_acpi_device(dev);
75         int len;
76
77         /* Device has no HID and no CID or string is >1024 */
78         len = create_modalias(acpi_dev, buf, 1024);
79         if (len <= 0)
80                 return 0;
81         buf[len++] = '\n';
82         return len;
83 }
84 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
85
86 static void acpi_bus_hot_remove_device(void *context)
87 {
88         struct acpi_device *device;
89         acpi_handle handle = context;
90         struct acpi_object_list arg_list;
91         union acpi_object arg;
92         acpi_status status = AE_OK;
93
94         if (acpi_bus_get_device(handle, &device))
95                 return;
96
97         if (!device)
98                 return;
99
100         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
101                 "Hot-removing device %s...\n", dev_name(&device->dev)));
102
103         if (acpi_bus_trim(device, 1)) {
104                 printk(KERN_ERR PREFIX
105                                 "Removing device failed\n");
106                 return;
107         }
108
109         /* power off device */
110         status = acpi_evaluate_object(handle, "_PS3", NULL, NULL);
111         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
112                 printk(KERN_WARNING PREFIX
113                                 "Power-off device failed\n");
114
115         if (device->flags.lockable) {
116                 arg_list.count = 1;
117                 arg_list.pointer = &arg;
118                 arg.type = ACPI_TYPE_INTEGER;
119                 arg.integer.value = 0;
120                 acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
121         }
122
123         arg_list.count = 1;
124         arg_list.pointer = &arg;
125         arg.type = ACPI_TYPE_INTEGER;
126         arg.integer.value = 1;
127
128         /*
129          * TBD: _EJD support.
130          */
131         status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
132         if (ACPI_FAILURE(status))
133                 printk(KERN_WARNING PREFIX
134                                 "Eject device failed\n");
135
136         return;
137 }
138
139 static ssize_t
140 acpi_eject_store(struct device *d, struct device_attribute *attr,
141                 const char *buf, size_t count)
142 {
143         int ret = count;
144         acpi_status status;
145         acpi_object_type type = 0;
146         struct acpi_device *acpi_device = to_acpi_device(d);
147
148         if ((!count) || (buf[0] != '1')) {
149                 return -EINVAL;
150         }
151 #ifndef FORCE_EJECT
152         if (acpi_device->driver == NULL) {
153                 ret = -ENODEV;
154                 goto err;
155         }
156 #endif
157         status = acpi_get_type(acpi_device->handle, &type);
158         if (ACPI_FAILURE(status) || (!acpi_device->flags.ejectable)) {
159                 ret = -ENODEV;
160                 goto err;
161         }
162
163         acpi_os_hotplug_execute(acpi_bus_hot_remove_device, acpi_device->handle);
164 err:
165         return ret;
166 }
167
168 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
169
170 static ssize_t
171 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
172         struct acpi_device *acpi_dev = to_acpi_device(dev);
173
174         return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
175 }
176 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
177
178 static ssize_t
179 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
180         struct acpi_device *acpi_dev = to_acpi_device(dev);
181         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
182         int result;
183
184         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
185         if (result)
186                 goto end;
187
188         result = sprintf(buf, "%s\n", (char*)path.pointer);
189         kfree(path.pointer);
190 end:
191         return result;
192 }
193 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
194
195 static int acpi_device_setup_files(struct acpi_device *dev)
196 {
197         acpi_status status;
198         acpi_handle temp;
199         int result = 0;
200
201         /*
202          * Devices gotten from FADT don't have a "path" attribute
203          */
204         if (dev->handle) {
205                 result = device_create_file(&dev->dev, &dev_attr_path);
206                 if (result)
207                         goto end;
208         }
209
210         if (!list_empty(&dev->pnp.ids)) {
211                 result = device_create_file(&dev->dev, &dev_attr_hid);
212                 if (result)
213                         goto end;
214
215                 result = device_create_file(&dev->dev, &dev_attr_modalias);
216                 if (result)
217                         goto end;
218         }
219
220         /*
221          * If device has _EJ0, 'eject' file is created that is used to trigger
222          * hot-removal function from userland.
223          */
224         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
225         if (ACPI_SUCCESS(status))
226                 result = device_create_file(&dev->dev, &dev_attr_eject);
227 end:
228         return result;
229 }
230
231 static void acpi_device_remove_files(struct acpi_device *dev)
232 {
233         acpi_status status;
234         acpi_handle temp;
235
236         /*
237          * If device has _EJ0, 'eject' file is created that is used to trigger
238          * hot-removal function from userland.
239          */
240         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
241         if (ACPI_SUCCESS(status))
242                 device_remove_file(&dev->dev, &dev_attr_eject);
243
244         device_remove_file(&dev->dev, &dev_attr_modalias);
245         device_remove_file(&dev->dev, &dev_attr_hid);
246         if (dev->handle)
247                 device_remove_file(&dev->dev, &dev_attr_path);
248 }
249 /* --------------------------------------------------------------------------
250                         ACPI Bus operations
251    -------------------------------------------------------------------------- */
252
253 int acpi_match_device_ids(struct acpi_device *device,
254                           const struct acpi_device_id *ids)
255 {
256         const struct acpi_device_id *id;
257         struct acpi_hardware_id *hwid;
258
259         /*
260          * If the device is not present, it is unnecessary to load device
261          * driver for it.
262          */
263         if (!device->status.present)
264                 return -ENODEV;
265
266         for (id = ids; id->id[0]; id++)
267                 list_for_each_entry(hwid, &device->pnp.ids, list)
268                         if (!strcmp((char *) id->id, hwid->id))
269                                 return 0;
270
271         return -ENOENT;
272 }
273 EXPORT_SYMBOL(acpi_match_device_ids);
274
275 static void acpi_free_ids(struct acpi_device *device)
276 {
277         struct acpi_hardware_id *id, *tmp;
278
279         list_for_each_entry_safe(id, tmp, &device->pnp.ids, list) {
280                 kfree(id->id);
281                 kfree(id);
282         }
283 }
284
285 static void acpi_device_release(struct device *dev)
286 {
287         struct acpi_device *acpi_dev = to_acpi_device(dev);
288
289         acpi_free_ids(acpi_dev);
290         kfree(acpi_dev);
291 }
292
293 static int acpi_device_suspend(struct device *dev, pm_message_t state)
294 {
295         struct acpi_device *acpi_dev = to_acpi_device(dev);
296         struct acpi_driver *acpi_drv = acpi_dev->driver;
297
298         if (acpi_drv && acpi_drv->ops.suspend)
299                 return acpi_drv->ops.suspend(acpi_dev, state);
300         return 0;
301 }
302
303 static int acpi_device_resume(struct device *dev)
304 {
305         struct acpi_device *acpi_dev = to_acpi_device(dev);
306         struct acpi_driver *acpi_drv = acpi_dev->driver;
307
308         if (acpi_drv && acpi_drv->ops.resume)
309                 return acpi_drv->ops.resume(acpi_dev);
310         return 0;
311 }
312
313 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
314 {
315         struct acpi_device *acpi_dev = to_acpi_device(dev);
316         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
317
318         return !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
319 }
320
321 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
322 {
323         struct acpi_device *acpi_dev = to_acpi_device(dev);
324         int len;
325
326         if (list_empty(&acpi_dev->pnp.ids))
327                 return 0;
328
329         if (add_uevent_var(env, "MODALIAS="))
330                 return -ENOMEM;
331         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
332                               sizeof(env->buf) - env->buflen);
333         if (len >= (sizeof(env->buf) - env->buflen))
334                 return -ENOMEM;
335         env->buflen += len;
336         return 0;
337 }
338
339 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
340 {
341         struct acpi_device *device = data;
342
343         device->driver->ops.notify(device, event);
344 }
345
346 static acpi_status acpi_device_notify_fixed(void *data)
347 {
348         struct acpi_device *device = data;
349
350         /* Fixed hardware devices have no handles */
351         acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
352         return AE_OK;
353 }
354
355 static int acpi_device_install_notify_handler(struct acpi_device *device)
356 {
357         acpi_status status;
358
359         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
360                 status =
361                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
362                                                      acpi_device_notify_fixed,
363                                                      device);
364         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
365                 status =
366                     acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
367                                                      acpi_device_notify_fixed,
368                                                      device);
369         else
370                 status = acpi_install_notify_handler(device->handle,
371                                                      ACPI_DEVICE_NOTIFY,
372                                                      acpi_device_notify,
373                                                      device);
374
375         if (ACPI_FAILURE(status))
376                 return -EINVAL;
377         return 0;
378 }
379
380 static void acpi_device_remove_notify_handler(struct acpi_device *device)
381 {
382         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
383                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
384                                                 acpi_device_notify_fixed);
385         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
386                 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
387                                                 acpi_device_notify_fixed);
388         else
389                 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
390                                            acpi_device_notify);
391 }
392
393 static int acpi_bus_driver_init(struct acpi_device *, struct acpi_driver *);
394 static int acpi_start_single_object(struct acpi_device *);
395 static int acpi_device_probe(struct device * dev)
396 {
397         struct acpi_device *acpi_dev = to_acpi_device(dev);
398         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
399         int ret;
400
401         ret = acpi_bus_driver_init(acpi_dev, acpi_drv);
402         if (!ret) {
403                 if (acpi_dev->bus_ops.acpi_op_start)
404                         acpi_start_single_object(acpi_dev);
405
406                 if (acpi_drv->ops.notify) {
407                         ret = acpi_device_install_notify_handler(acpi_dev);
408                         if (ret) {
409                                 if (acpi_drv->ops.remove)
410                                         acpi_drv->ops.remove(acpi_dev,
411                                                      acpi_dev->removal_type);
412                                 return ret;
413                         }
414                 }
415
416                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
417                         "Found driver [%s] for device [%s]\n",
418                         acpi_drv->name, acpi_dev->pnp.bus_id));
419                 get_device(dev);
420         }
421         return ret;
422 }
423
424 static int acpi_device_remove(struct device * dev)
425 {
426         struct acpi_device *acpi_dev = to_acpi_device(dev);
427         struct acpi_driver *acpi_drv = acpi_dev->driver;
428
429         if (acpi_drv) {
430                 if (acpi_drv->ops.notify)
431                         acpi_device_remove_notify_handler(acpi_dev);
432                 if (acpi_drv->ops.remove)
433                         acpi_drv->ops.remove(acpi_dev, acpi_dev->removal_type);
434         }
435         acpi_dev->driver = NULL;
436         acpi_dev->driver_data = NULL;
437
438         put_device(dev);
439         return 0;
440 }
441
442 struct bus_type acpi_bus_type = {
443         .name           = "acpi",
444         .suspend        = acpi_device_suspend,
445         .resume         = acpi_device_resume,
446         .match          = acpi_bus_match,
447         .probe          = acpi_device_probe,
448         .remove         = acpi_device_remove,
449         .uevent         = acpi_device_uevent,
450 };
451
452 static int acpi_device_register(struct acpi_device *device)
453 {
454         int result;
455         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
456         int found = 0;
457
458         /*
459          * Linkage
460          * -------
461          * Link this device to its parent and siblings.
462          */
463         INIT_LIST_HEAD(&device->children);
464         INIT_LIST_HEAD(&device->node);
465         INIT_LIST_HEAD(&device->wakeup_list);
466
467         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
468         if (!new_bus_id) {
469                 printk(KERN_ERR PREFIX "Memory allocation error\n");
470                 return -ENOMEM;
471         }
472
473         mutex_lock(&acpi_device_lock);
474         /*
475          * Find suitable bus_id and instance number in acpi_bus_id_list
476          * If failed, create one and link it into acpi_bus_id_list
477          */
478         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
479                 if (!strcmp(acpi_device_bus_id->bus_id,
480                             acpi_device_hid(device))) {
481                         acpi_device_bus_id->instance_no++;
482                         found = 1;
483                         kfree(new_bus_id);
484                         break;
485                 }
486         }
487         if (!found) {
488                 acpi_device_bus_id = new_bus_id;
489                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
490                 acpi_device_bus_id->instance_no = 0;
491                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
492         }
493         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
494
495         if (device->parent)
496                 list_add_tail(&device->node, &device->parent->children);
497
498         if (device->wakeup.flags.valid)
499                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
500         mutex_unlock(&acpi_device_lock);
501
502         if (device->parent)
503                 device->dev.parent = &device->parent->dev;
504         device->dev.bus = &acpi_bus_type;
505         device->dev.release = &acpi_device_release;
506         result = device_register(&device->dev);
507         if (result) {
508                 dev_err(&device->dev, "Error registering device\n");
509                 goto end;
510         }
511
512         result = acpi_device_setup_files(device);
513         if (result)
514                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
515                        dev_name(&device->dev));
516
517         device->removal_type = ACPI_BUS_REMOVAL_NORMAL;
518         return 0;
519 end:
520         mutex_lock(&acpi_device_lock);
521         if (device->parent)
522                 list_del(&device->node);
523         list_del(&device->wakeup_list);
524         mutex_unlock(&acpi_device_lock);
525         return result;
526 }
527
528 static void acpi_device_unregister(struct acpi_device *device, int type)
529 {
530         mutex_lock(&acpi_device_lock);
531         if (device->parent)
532                 list_del(&device->node);
533
534         list_del(&device->wakeup_list);
535         mutex_unlock(&acpi_device_lock);
536
537         acpi_detach_data(device->handle, acpi_bus_data_handler);
538
539         acpi_device_remove_files(device);
540         device_unregister(&device->dev);
541 }
542
543 /* --------------------------------------------------------------------------
544                                  Driver Management
545    -------------------------------------------------------------------------- */
546 /**
547  * acpi_bus_driver_init - add a device to a driver
548  * @device: the device to add and initialize
549  * @driver: driver for the device
550  *
551  * Used to initialize a device via its device driver.  Called whenever a
552  * driver is bound to a device.  Invokes the driver's add() ops.
553  */
554 static int
555 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
556 {
557         int result = 0;
558
559         if (!device || !driver)
560                 return -EINVAL;
561
562         if (!driver->ops.add)
563                 return -ENOSYS;
564
565         result = driver->ops.add(device);
566         if (result) {
567                 device->driver = NULL;
568                 device->driver_data = NULL;
569                 return result;
570         }
571
572         device->driver = driver;
573
574         /*
575          * TBD - Configuration Management: Assign resources to device based
576          * upon possible configuration and currently allocated resources.
577          */
578
579         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
580                           "Driver successfully bound to device\n"));
581         return 0;
582 }
583
584 static int acpi_start_single_object(struct acpi_device *device)
585 {
586         int result = 0;
587         struct acpi_driver *driver;
588
589
590         if (!(driver = device->driver))
591                 return 0;
592
593         if (driver->ops.start) {
594                 result = driver->ops.start(device);
595                 if (result && driver->ops.remove)
596                         driver->ops.remove(device, ACPI_BUS_REMOVAL_NORMAL);
597         }
598
599         return result;
600 }
601
602 /**
603  * acpi_bus_register_driver - register a driver with the ACPI bus
604  * @driver: driver being registered
605  *
606  * Registers a driver with the ACPI bus.  Searches the namespace for all
607  * devices that match the driver's criteria and binds.  Returns zero for
608  * success or a negative error status for failure.
609  */
610 int acpi_bus_register_driver(struct acpi_driver *driver)
611 {
612         int ret;
613
614         if (acpi_disabled)
615                 return -ENODEV;
616         driver->drv.name = driver->name;
617         driver->drv.bus = &acpi_bus_type;
618         driver->drv.owner = driver->owner;
619
620         ret = driver_register(&driver->drv);
621         return ret;
622 }
623
624 EXPORT_SYMBOL(acpi_bus_register_driver);
625
626 /**
627  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
628  * @driver: driver to unregister
629  *
630  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
631  * devices that match the driver's criteria and unbinds.
632  */
633 void acpi_bus_unregister_driver(struct acpi_driver *driver)
634 {
635         driver_unregister(&driver->drv);
636 }
637
638 EXPORT_SYMBOL(acpi_bus_unregister_driver);
639
640 /* --------------------------------------------------------------------------
641                                  Device Enumeration
642    -------------------------------------------------------------------------- */
643 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
644 {
645         acpi_status status;
646         int ret;
647         struct acpi_device *device;
648
649         /*
650          * Fixed hardware devices do not appear in the namespace and do not
651          * have handles, but we fabricate acpi_devices for them, so we have
652          * to deal with them specially.
653          */
654         if (handle == NULL)
655                 return acpi_root;
656
657         do {
658                 status = acpi_get_parent(handle, &handle);
659                 if (status == AE_NULL_ENTRY)
660                         return NULL;
661                 if (ACPI_FAILURE(status))
662                         return acpi_root;
663
664                 ret = acpi_bus_get_device(handle, &device);
665                 if (ret == 0)
666                         return device;
667         } while (1);
668 }
669
670 acpi_status
671 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
672 {
673         acpi_status status;
674         acpi_handle tmp;
675         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
676         union acpi_object *obj;
677
678         status = acpi_get_handle(handle, "_EJD", &tmp);
679         if (ACPI_FAILURE(status))
680                 return status;
681
682         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
683         if (ACPI_SUCCESS(status)) {
684                 obj = buffer.pointer;
685                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
686                                          ejd);
687                 kfree(buffer.pointer);
688         }
689         return status;
690 }
691 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
692
693 void acpi_bus_data_handler(acpi_handle handle, void *context)
694 {
695
696         /* TBD */
697
698         return;
699 }
700
701 static int acpi_bus_get_perf_flags(struct acpi_device *device)
702 {
703         device->performance.state = ACPI_STATE_UNKNOWN;
704         return 0;
705 }
706
707 static acpi_status
708 acpi_bus_extract_wakeup_device_power_package(struct acpi_device *device,
709                                              union acpi_object *package)
710 {
711         int i = 0;
712         union acpi_object *element = NULL;
713
714         if (!device || !package || (package->package.count < 2))
715                 return AE_BAD_PARAMETER;
716
717         element = &(package->package.elements[0]);
718         if (!element)
719                 return AE_BAD_PARAMETER;
720         if (element->type == ACPI_TYPE_PACKAGE) {
721                 if ((element->package.count < 2) ||
722                     (element->package.elements[0].type !=
723                      ACPI_TYPE_LOCAL_REFERENCE)
724                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
725                         return AE_BAD_DATA;
726                 device->wakeup.gpe_device =
727                     element->package.elements[0].reference.handle;
728                 device->wakeup.gpe_number =
729                     (u32) element->package.elements[1].integer.value;
730         } else if (element->type == ACPI_TYPE_INTEGER) {
731                 device->wakeup.gpe_number = element->integer.value;
732         } else
733                 return AE_BAD_DATA;
734
735         element = &(package->package.elements[1]);
736         if (element->type != ACPI_TYPE_INTEGER) {
737                 return AE_BAD_DATA;
738         }
739         device->wakeup.sleep_state = element->integer.value;
740
741         if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
742                 return AE_NO_MEMORY;
743         }
744         device->wakeup.resources.count = package->package.count - 2;
745         for (i = 0; i < device->wakeup.resources.count; i++) {
746                 element = &(package->package.elements[i + 2]);
747                 if (element->type != ACPI_TYPE_LOCAL_REFERENCE)
748                         return AE_BAD_DATA;
749
750                 device->wakeup.resources.handles[i] = element->reference.handle;
751         }
752
753         acpi_gpe_can_wake(device->wakeup.gpe_device, device->wakeup.gpe_number);
754
755         return AE_OK;
756 }
757
758 static void acpi_bus_set_run_wake_flags(struct acpi_device *device)
759 {
760         struct acpi_device_id button_device_ids[] = {
761                 {"PNP0C0D", 0},
762                 {"PNP0C0C", 0},
763                 {"PNP0C0E", 0},
764                 {"", 0},
765         };
766         acpi_status status;
767         acpi_event_status event_status;
768
769         device->wakeup.run_wake_count = 0;
770         device->wakeup.flags.notifier_present = 0;
771
772         /* Power button, Lid switch always enable wakeup */
773         if (!acpi_match_device_ids(device, button_device_ids)) {
774                 device->wakeup.flags.run_wake = 1;
775                 device->wakeup.flags.always_enabled = 1;
776                 return;
777         }
778
779         status = acpi_get_gpe_status(device->wakeup.gpe_device,
780                                         device->wakeup.gpe_number,
781                                                 &event_status);
782         if (status == AE_OK)
783                 device->wakeup.flags.run_wake =
784                                 !!(event_status & ACPI_EVENT_FLAG_HANDLE);
785 }
786
787 static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
788 {
789         acpi_status status = 0;
790         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
791         union acpi_object *package = NULL;
792         int psw_error;
793
794         /* _PRW */
795         status = acpi_evaluate_object(device->handle, "_PRW", NULL, &buffer);
796         if (ACPI_FAILURE(status)) {
797                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
798                 goto end;
799         }
800
801         package = (union acpi_object *)buffer.pointer;
802         status = acpi_bus_extract_wakeup_device_power_package(device, package);
803         if (ACPI_FAILURE(status)) {
804                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _PRW package"));
805                 goto end;
806         }
807
808         kfree(buffer.pointer);
809
810         device->wakeup.flags.valid = 1;
811         device->wakeup.prepare_count = 0;
812         acpi_bus_set_run_wake_flags(device);
813         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
814          * system for the ACPI device with the _PRW object.
815          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
816          * So it is necessary to call _DSW object first. Only when it is not
817          * present will the _PSW object used.
818          */
819         psw_error = acpi_device_sleep_wake(device, 0, 0, 0);
820         if (psw_error)
821                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
822                                 "error in _DSW or _PSW evaluation\n"));
823
824 end:
825         if (ACPI_FAILURE(status))
826                 device->flags.wake_capable = 0;
827         return 0;
828 }
829
830 static int acpi_bus_get_power_flags(struct acpi_device *device)
831 {
832         acpi_status status = 0;
833         acpi_handle handle = NULL;
834         u32 i = 0;
835
836
837         /*
838          * Power Management Flags
839          */
840         status = acpi_get_handle(device->handle, "_PSC", &handle);
841         if (ACPI_SUCCESS(status))
842                 device->power.flags.explicit_get = 1;
843         status = acpi_get_handle(device->handle, "_IRC", &handle);
844         if (ACPI_SUCCESS(status))
845                 device->power.flags.inrush_current = 1;
846
847         /*
848          * Enumerate supported power management states
849          */
850         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
851                 struct acpi_device_power_state *ps = &device->power.states[i];
852                 char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
853
854                 /* Evaluate "_PRx" to se if power resources are referenced */
855                 acpi_evaluate_reference(device->handle, object_name, NULL,
856                                         &ps->resources);
857                 if (ps->resources.count) {
858                         device->power.flags.power_resources = 1;
859                         ps->flags.valid = 1;
860                 }
861
862                 /* Evaluate "_PSx" to see if we can do explicit sets */
863                 object_name[2] = 'S';
864                 status = acpi_get_handle(device->handle, object_name, &handle);
865                 if (ACPI_SUCCESS(status)) {
866                         ps->flags.explicit_set = 1;
867                         ps->flags.valid = 1;
868                 }
869
870                 /* State is valid if we have some power control */
871                 if (ps->resources.count || ps->flags.explicit_set)
872                         ps->flags.valid = 1;
873
874                 ps->power = -1; /* Unknown - driver assigned */
875                 ps->latency = -1;       /* Unknown - driver assigned */
876         }
877
878         /* Set defaults for D0 and D3 states (always valid) */
879         device->power.states[ACPI_STATE_D0].flags.valid = 1;
880         device->power.states[ACPI_STATE_D0].power = 100;
881         device->power.states[ACPI_STATE_D3].flags.valid = 1;
882         device->power.states[ACPI_STATE_D3].power = 0;
883
884         /* TBD: System wake support and resource requirements. */
885
886         device->power.state = ACPI_STATE_UNKNOWN;
887         acpi_bus_get_power(device->handle, &(device->power.state));
888
889         return 0;
890 }
891
892 static int acpi_bus_get_flags(struct acpi_device *device)
893 {
894         acpi_status status = AE_OK;
895         acpi_handle temp = NULL;
896
897
898         /* Presence of _STA indicates 'dynamic_status' */
899         status = acpi_get_handle(device->handle, "_STA", &temp);
900         if (ACPI_SUCCESS(status))
901                 device->flags.dynamic_status = 1;
902
903         /* Presence of _RMV indicates 'removable' */
904         status = acpi_get_handle(device->handle, "_RMV", &temp);
905         if (ACPI_SUCCESS(status))
906                 device->flags.removable = 1;
907
908         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
909         status = acpi_get_handle(device->handle, "_EJD", &temp);
910         if (ACPI_SUCCESS(status))
911                 device->flags.ejectable = 1;
912         else {
913                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
914                 if (ACPI_SUCCESS(status))
915                         device->flags.ejectable = 1;
916         }
917
918         /* Presence of _LCK indicates 'lockable' */
919         status = acpi_get_handle(device->handle, "_LCK", &temp);
920         if (ACPI_SUCCESS(status))
921                 device->flags.lockable = 1;
922
923         /* Presence of _PS0|_PR0 indicates 'power manageable' */
924         status = acpi_get_handle(device->handle, "_PS0", &temp);
925         if (ACPI_FAILURE(status))
926                 status = acpi_get_handle(device->handle, "_PR0", &temp);
927         if (ACPI_SUCCESS(status))
928                 device->flags.power_manageable = 1;
929
930         /* Presence of _PRW indicates wake capable */
931         status = acpi_get_handle(device->handle, "_PRW", &temp);
932         if (ACPI_SUCCESS(status))
933                 device->flags.wake_capable = 1;
934
935         /* TBD: Performance management */
936
937         return 0;
938 }
939
940 static void acpi_device_get_busid(struct acpi_device *device)
941 {
942         char bus_id[5] = { '?', 0 };
943         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
944         int i = 0;
945
946         /*
947          * Bus ID
948          * ------
949          * The device's Bus ID is simply the object name.
950          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
951          */
952         if (ACPI_IS_ROOT_DEVICE(device)) {
953                 strcpy(device->pnp.bus_id, "ACPI");
954                 return;
955         }
956
957         switch (device->device_type) {
958         case ACPI_BUS_TYPE_POWER_BUTTON:
959                 strcpy(device->pnp.bus_id, "PWRF");
960                 break;
961         case ACPI_BUS_TYPE_SLEEP_BUTTON:
962                 strcpy(device->pnp.bus_id, "SLPF");
963                 break;
964         default:
965                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
966                 /* Clean up trailing underscores (if any) */
967                 for (i = 3; i > 1; i--) {
968                         if (bus_id[i] == '_')
969                                 bus_id[i] = '\0';
970                         else
971                                 break;
972                 }
973                 strcpy(device->pnp.bus_id, bus_id);
974                 break;
975         }
976 }
977
978 /*
979  * acpi_bay_match - see if a device is an ejectable driver bay
980  *
981  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
982  * then we can safely call it an ejectable drive bay
983  */
984 static int acpi_bay_match(struct acpi_device *device){
985         acpi_status status;
986         acpi_handle handle;
987         acpi_handle tmp;
988         acpi_handle phandle;
989
990         handle = device->handle;
991
992         status = acpi_get_handle(handle, "_EJ0", &tmp);
993         if (ACPI_FAILURE(status))
994                 return -ENODEV;
995
996         if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
997                 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
998                 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
999                 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
1000                 return 0;
1001
1002         if (acpi_get_parent(handle, &phandle))
1003                 return -ENODEV;
1004
1005         if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
1006                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
1007                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
1008                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
1009                 return 0;
1010
1011         return -ENODEV;
1012 }
1013
1014 /*
1015  * acpi_dock_match - see if a device has a _DCK method
1016  */
1017 static int acpi_dock_match(struct acpi_device *device)
1018 {
1019         acpi_handle tmp;
1020         return acpi_get_handle(device->handle, "_DCK", &tmp);
1021 }
1022
1023 const char *acpi_device_hid(struct acpi_device *device)
1024 {
1025         struct acpi_hardware_id *hid;
1026
1027         if (list_empty(&device->pnp.ids))
1028                 return dummy_hid;
1029
1030         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1031         return hid->id;
1032 }
1033 EXPORT_SYMBOL(acpi_device_hid);
1034
1035 static void acpi_add_id(struct acpi_device *device, const char *dev_id)
1036 {
1037         struct acpi_hardware_id *id;
1038
1039         id = kmalloc(sizeof(*id), GFP_KERNEL);
1040         if (!id)
1041                 return;
1042
1043         id->id = kmalloc(strlen(dev_id) + 1, GFP_KERNEL);
1044         if (!id->id) {
1045                 kfree(id);
1046                 return;
1047         }
1048
1049         strcpy(id->id, dev_id);
1050         list_add_tail(&id->list, &device->pnp.ids);
1051 }
1052
1053 /*
1054  * Old IBM workstations have a DSDT bug wherein the SMBus object
1055  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1056  * prefix.  Work around this.
1057  */
1058 static int acpi_ibm_smbus_match(struct acpi_device *device)
1059 {
1060         acpi_handle h_dummy;
1061         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
1062         int result;
1063
1064         if (!dmi_name_in_vendors("IBM"))
1065                 return -ENODEV;
1066
1067         /* Look for SMBS object */
1068         result = acpi_get_name(device->handle, ACPI_SINGLE_NAME, &path);
1069         if (result)
1070                 return result;
1071
1072         if (strcmp("SMBS", path.pointer)) {
1073                 result = -ENODEV;
1074                 goto out;
1075         }
1076
1077         /* Does it have the necessary (but misnamed) methods? */
1078         result = -ENODEV;
1079         if (ACPI_SUCCESS(acpi_get_handle(device->handle, "SBI", &h_dummy)) &&
1080             ACPI_SUCCESS(acpi_get_handle(device->handle, "SBR", &h_dummy)) &&
1081             ACPI_SUCCESS(acpi_get_handle(device->handle, "SBW", &h_dummy)))
1082                 result = 0;
1083 out:
1084         kfree(path.pointer);
1085         return result;
1086 }
1087
1088 static void acpi_device_set_id(struct acpi_device *device)
1089 {
1090         acpi_status status;
1091         struct acpi_device_info *info;
1092         struct acpica_device_id_list *cid_list;
1093         int i;
1094
1095         switch (device->device_type) {
1096         case ACPI_BUS_TYPE_DEVICE:
1097                 if (ACPI_IS_ROOT_DEVICE(device)) {
1098                         acpi_add_id(device, ACPI_SYSTEM_HID);
1099                         break;
1100                 }
1101
1102                 status = acpi_get_object_info(device->handle, &info);
1103                 if (ACPI_FAILURE(status)) {
1104                         printk(KERN_ERR PREFIX "%s: Error reading device info\n", __func__);
1105                         return;
1106                 }
1107
1108                 if (info->valid & ACPI_VALID_HID)
1109                         acpi_add_id(device, info->hardware_id.string);
1110                 if (info->valid & ACPI_VALID_CID) {
1111                         cid_list = &info->compatible_id_list;
1112                         for (i = 0; i < cid_list->count; i++)
1113                                 acpi_add_id(device, cid_list->ids[i].string);
1114                 }
1115                 if (info->valid & ACPI_VALID_ADR) {
1116                         device->pnp.bus_address = info->address;
1117                         device->flags.bus_address = 1;
1118                 }
1119
1120                 kfree(info);
1121
1122                 /*
1123                  * Some devices don't reliably have _HIDs & _CIDs, so add
1124                  * synthetic HIDs to make sure drivers can find them.
1125                  */
1126                 if (acpi_is_video_device(device))
1127                         acpi_add_id(device, ACPI_VIDEO_HID);
1128                 else if (ACPI_SUCCESS(acpi_bay_match(device)))
1129                         acpi_add_id(device, ACPI_BAY_HID);
1130                 else if (ACPI_SUCCESS(acpi_dock_match(device)))
1131                         acpi_add_id(device, ACPI_DOCK_HID);
1132                 else if (!acpi_ibm_smbus_match(device))
1133                         acpi_add_id(device, ACPI_SMBUS_IBM_HID);
1134                 else if (!acpi_device_hid(device) &&
1135                          ACPI_IS_ROOT_DEVICE(device->parent)) {
1136                         acpi_add_id(device, ACPI_BUS_HID); /* \_SB, LNXSYBUS */
1137                         strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
1138                         strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
1139                 }
1140
1141                 break;
1142         case ACPI_BUS_TYPE_POWER:
1143                 acpi_add_id(device, ACPI_POWER_HID);
1144                 break;
1145         case ACPI_BUS_TYPE_PROCESSOR:
1146                 acpi_add_id(device, ACPI_PROCESSOR_OBJECT_HID);
1147                 break;
1148         case ACPI_BUS_TYPE_THERMAL:
1149                 acpi_add_id(device, ACPI_THERMAL_HID);
1150                 break;
1151         case ACPI_BUS_TYPE_POWER_BUTTON:
1152                 acpi_add_id(device, ACPI_BUTTON_HID_POWERF);
1153                 break;
1154         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1155                 acpi_add_id(device, ACPI_BUTTON_HID_SLEEPF);
1156                 break;
1157         }
1158 }
1159
1160 static int acpi_device_set_context(struct acpi_device *device)
1161 {
1162         acpi_status status;
1163
1164         /*
1165          * Context
1166          * -------
1167          * Attach this 'struct acpi_device' to the ACPI object.  This makes
1168          * resolutions from handle->device very efficient.  Fixed hardware
1169          * devices have no handles, so we skip them.
1170          */
1171         if (!device->handle)
1172                 return 0;
1173
1174         status = acpi_attach_data(device->handle,
1175                                   acpi_bus_data_handler, device);
1176         if (ACPI_SUCCESS(status))
1177                 return 0;
1178
1179         printk(KERN_ERR PREFIX "Error attaching device data\n");
1180         return -ENODEV;
1181 }
1182
1183 static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
1184 {
1185         if (!dev)
1186                 return -EINVAL;
1187
1188         dev->removal_type = ACPI_BUS_REMOVAL_EJECT;
1189         device_release_driver(&dev->dev);
1190
1191         if (!rmdevice)
1192                 return 0;
1193
1194         /*
1195          * unbind _ADR-Based Devices when hot removal
1196          */
1197         if (dev->flags.bus_address) {
1198                 if ((dev->parent) && (dev->parent->ops.unbind))
1199                         dev->parent->ops.unbind(dev);
1200         }
1201         acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
1202
1203         return 0;
1204 }
1205
1206 static int acpi_add_single_object(struct acpi_device **child,
1207                                   acpi_handle handle, int type,
1208                                   unsigned long long sta,
1209                                   struct acpi_bus_ops *ops)
1210 {
1211         int result;
1212         struct acpi_device *device;
1213         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1214
1215         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1216         if (!device) {
1217                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1218                 return -ENOMEM;
1219         }
1220
1221         INIT_LIST_HEAD(&device->pnp.ids);
1222         device->device_type = type;
1223         device->handle = handle;
1224         device->parent = acpi_bus_get_parent(handle);
1225         device->bus_ops = *ops; /* workround for not call .start */
1226         STRUCT_TO_INT(device->status) = sta;
1227
1228         acpi_device_get_busid(device);
1229
1230         /*
1231          * Flags
1232          * -----
1233          * Note that we only look for object handles -- cannot evaluate objects
1234          * until we know the device is present and properly initialized.
1235          */
1236         result = acpi_bus_get_flags(device);
1237         if (result)
1238                 goto end;
1239
1240         /*
1241          * Initialize Device
1242          * -----------------
1243          * TBD: Synch with Core's enumeration/initialization process.
1244          */
1245         acpi_device_set_id(device);
1246
1247         /*
1248          * Power Management
1249          * ----------------
1250          */
1251         if (device->flags.power_manageable) {
1252                 result = acpi_bus_get_power_flags(device);
1253                 if (result)
1254                         goto end;
1255         }
1256
1257         /*
1258          * Wakeup device management
1259          *-----------------------
1260          */
1261         if (device->flags.wake_capable) {
1262                 result = acpi_bus_get_wakeup_device_flags(device);
1263                 if (result)
1264                         goto end;
1265         }
1266
1267         /*
1268          * Performance Management
1269          * ----------------------
1270          */
1271         if (device->flags.performance_manageable) {
1272                 result = acpi_bus_get_perf_flags(device);
1273                 if (result)
1274                         goto end;
1275         }
1276
1277         if ((result = acpi_device_set_context(device)))
1278                 goto end;
1279
1280         result = acpi_device_register(device);
1281
1282         /*
1283          * Bind _ADR-Based Devices when hot add
1284          */
1285         if (device->flags.bus_address) {
1286                 if (device->parent && device->parent->ops.bind)
1287                         device->parent->ops.bind(device);
1288         }
1289
1290 end:
1291         if (!result) {
1292                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1293                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1294                         "Adding %s [%s] parent %s\n", dev_name(&device->dev),
1295                          (char *) buffer.pointer,
1296                          device->parent ? dev_name(&device->parent->dev) :
1297                                           "(null)"));
1298                 kfree(buffer.pointer);
1299                 *child = device;
1300         } else
1301                 acpi_device_release(&device->dev);
1302
1303         return result;
1304 }
1305
1306 #define ACPI_STA_DEFAULT (ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED | \
1307                           ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING)
1308
1309 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1310                                     unsigned long long *sta)
1311 {
1312         acpi_status status;
1313         acpi_object_type acpi_type;
1314
1315         status = acpi_get_type(handle, &acpi_type);
1316         if (ACPI_FAILURE(status))
1317                 return -ENODEV;
1318
1319         switch (acpi_type) {
1320         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1321         case ACPI_TYPE_DEVICE:
1322                 *type = ACPI_BUS_TYPE_DEVICE;
1323                 status = acpi_bus_get_status_handle(handle, sta);
1324                 if (ACPI_FAILURE(status))
1325                         return -ENODEV;
1326                 break;
1327         case ACPI_TYPE_PROCESSOR:
1328                 *type = ACPI_BUS_TYPE_PROCESSOR;
1329                 status = acpi_bus_get_status_handle(handle, sta);
1330                 if (ACPI_FAILURE(status))
1331                         return -ENODEV;
1332                 break;
1333         case ACPI_TYPE_THERMAL:
1334                 *type = ACPI_BUS_TYPE_THERMAL;
1335                 *sta = ACPI_STA_DEFAULT;
1336                 break;
1337         case ACPI_TYPE_POWER:
1338                 *type = ACPI_BUS_TYPE_POWER;
1339                 *sta = ACPI_STA_DEFAULT;
1340                 break;
1341         default:
1342                 return -ENODEV;
1343         }
1344
1345         return 0;
1346 }
1347
1348 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl,
1349                                       void *context, void **return_value)
1350 {
1351         struct acpi_bus_ops *ops = context;
1352         int type;
1353         unsigned long long sta;
1354         struct acpi_device *device;
1355         acpi_status status;
1356         int result;
1357
1358         result = acpi_bus_type_and_status(handle, &type, &sta);
1359         if (result)
1360                 return AE_OK;
1361
1362         if (!(sta & ACPI_STA_DEVICE_PRESENT) &&
1363             !(sta & ACPI_STA_DEVICE_FUNCTIONING))
1364                 return AE_CTRL_DEPTH;
1365
1366         /*
1367          * We may already have an acpi_device from a previous enumeration.  If
1368          * so, we needn't add it again, but we may still have to start it.
1369          */
1370         device = NULL;
1371         acpi_bus_get_device(handle, &device);
1372         if (ops->acpi_op_add && !device)
1373                 acpi_add_single_object(&device, handle, type, sta, ops);
1374
1375         if (!device)
1376                 return AE_CTRL_DEPTH;
1377
1378         if (ops->acpi_op_start && !(ops->acpi_op_add)) {
1379                 status = acpi_start_single_object(device);
1380                 if (ACPI_FAILURE(status))
1381                         return AE_CTRL_DEPTH;
1382         }
1383
1384         if (!*return_value)
1385                 *return_value = device;
1386         return AE_OK;
1387 }
1388
1389 static int acpi_bus_scan(acpi_handle handle, struct acpi_bus_ops *ops,
1390                          struct acpi_device **child)
1391 {
1392         acpi_status status;
1393         void *device = NULL;
1394
1395         status = acpi_bus_check_add(handle, 0, ops, &device);
1396         if (ACPI_SUCCESS(status))
1397                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1398                                     acpi_bus_check_add, NULL, ops, &device);
1399
1400         if (child)
1401                 *child = device;
1402
1403         if (device)
1404                 return 0;
1405         else
1406                 return -ENODEV;
1407 }
1408
1409 /*
1410  * acpi_bus_add and acpi_bus_start
1411  *
1412  * scan a given ACPI tree and (probably recently hot-plugged)
1413  * create and add or starts found devices.
1414  *
1415  * If no devices were found -ENODEV is returned which does not
1416  * mean that this is a real error, there just have been no suitable
1417  * ACPI objects in the table trunk from which the kernel could create
1418  * a device and add/start an appropriate driver.
1419  */
1420
1421 int
1422 acpi_bus_add(struct acpi_device **child,
1423              struct acpi_device *parent, acpi_handle handle, int type)
1424 {
1425         struct acpi_bus_ops ops;
1426
1427         memset(&ops, 0, sizeof(ops));
1428         ops.acpi_op_add = 1;
1429
1430         return acpi_bus_scan(handle, &ops, child);
1431 }
1432 EXPORT_SYMBOL(acpi_bus_add);
1433
1434 int acpi_bus_start(struct acpi_device *device)
1435 {
1436         struct acpi_bus_ops ops;
1437         int result;
1438
1439         if (!device)
1440                 return -EINVAL;
1441
1442         memset(&ops, 0, sizeof(ops));
1443         ops.acpi_op_start = 1;
1444
1445         result = acpi_bus_scan(device->handle, &ops, NULL);
1446
1447         acpi_update_gpes();
1448
1449         return result;
1450 }
1451 EXPORT_SYMBOL(acpi_bus_start);
1452
1453 int acpi_bus_trim(struct acpi_device *start, int rmdevice)
1454 {
1455         acpi_status status;
1456         struct acpi_device *parent, *child;
1457         acpi_handle phandle, chandle;
1458         acpi_object_type type;
1459         u32 level = 1;
1460         int err = 0;
1461
1462         parent = start;
1463         phandle = start->handle;
1464         child = chandle = NULL;
1465
1466         while ((level > 0) && parent && (!err)) {
1467                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1468                                               chandle, &chandle);
1469
1470                 /*
1471                  * If this scope is exhausted then move our way back up.
1472                  */
1473                 if (ACPI_FAILURE(status)) {
1474                         level--;
1475                         chandle = phandle;
1476                         acpi_get_parent(phandle, &phandle);
1477                         child = parent;
1478                         parent = parent->parent;
1479
1480                         if (level == 0)
1481                                 err = acpi_bus_remove(child, rmdevice);
1482                         else
1483                                 err = acpi_bus_remove(child, 1);
1484
1485                         continue;
1486                 }
1487
1488                 status = acpi_get_type(chandle, &type);
1489                 if (ACPI_FAILURE(status)) {
1490                         continue;
1491                 }
1492                 /*
1493                  * If there is a device corresponding to chandle then
1494                  * parse it (depth-first).
1495                  */
1496                 if (acpi_bus_get_device(chandle, &child) == 0) {
1497                         level++;
1498                         phandle = chandle;
1499                         chandle = NULL;
1500                         parent = child;
1501                 }
1502                 continue;
1503         }
1504         return err;
1505 }
1506 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1507
1508 static int acpi_bus_scan_fixed(void)
1509 {
1510         int result = 0;
1511         struct acpi_device *device = NULL;
1512         struct acpi_bus_ops ops;
1513
1514         memset(&ops, 0, sizeof(ops));
1515         ops.acpi_op_add = 1;
1516         ops.acpi_op_start = 1;
1517
1518         /*
1519          * Enumerate all fixed-feature devices.
1520          */
1521         if ((acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON) == 0) {
1522                 result = acpi_add_single_object(&device, NULL,
1523                                                 ACPI_BUS_TYPE_POWER_BUTTON,
1524                                                 ACPI_STA_DEFAULT,
1525                                                 &ops);
1526         }
1527
1528         if ((acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON) == 0) {
1529                 result = acpi_add_single_object(&device, NULL,
1530                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
1531                                                 ACPI_STA_DEFAULT,
1532                                                 &ops);
1533         }
1534
1535         return result;
1536 }
1537
1538 int __init acpi_scan_init(void)
1539 {
1540         int result;
1541         struct acpi_bus_ops ops;
1542
1543         memset(&ops, 0, sizeof(ops));
1544         ops.acpi_op_add = 1;
1545         ops.acpi_op_start = 1;
1546
1547         result = bus_register(&acpi_bus_type);
1548         if (result) {
1549                 /* We don't want to quit even if we failed to add suspend/resume */
1550                 printk(KERN_ERR PREFIX "Could not register bus type\n");
1551         }
1552
1553         /*
1554          * Enumerate devices in the ACPI namespace.
1555          */
1556         result = acpi_bus_scan(ACPI_ROOT_OBJECT, &ops, &acpi_root);
1557
1558         if (!result)
1559                 result = acpi_bus_scan_fixed();
1560
1561         if (result)
1562                 acpi_device_unregister(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
1563         else
1564                 acpi_update_gpes();
1565
1566         return result;
1567 }