ACPI: identify device tree root by null parent pointer, not ACPI_BUS_TYPE
[safe/jmp/linux-2.6] / 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/kernel.h>
8 #include <linux/acpi.h>
9 #include <linux/signal.h>
10 #include <linux/kthread.h>
11
12 #include <acpi/acpi_drivers.h>
13
14 #include "internal.h"
15
16 #define _COMPONENT              ACPI_BUS_COMPONENT
17 ACPI_MODULE_NAME("scan");
18 #define STRUCT_TO_INT(s)        (*((int*)&s))
19 extern struct acpi_device *acpi_root;
20
21 #define ACPI_BUS_CLASS                  "system_bus"
22 #define ACPI_BUS_HID                    "LNXSYBUS"
23 #define ACPI_BUS_DEVICE_NAME            "System Bus"
24
25 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
26
27 static LIST_HEAD(acpi_device_list);
28 static LIST_HEAD(acpi_bus_id_list);
29 DEFINE_MUTEX(acpi_device_lock);
30 LIST_HEAD(acpi_wakeup_device_list);
31
32 struct acpi_device_bus_id{
33         char bus_id[15];
34         unsigned int instance_no;
35         struct list_head node;
36 };
37
38 /*
39  * Creates hid/cid(s) string needed for modalias and uevent
40  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
41  * char *modalias: "acpi:IBM0001:ACPI0001"
42 */
43 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
44                            int size)
45 {
46         int len;
47         int count;
48
49         if (!acpi_dev->flags.hardware_id && !acpi_dev->flags.compatible_ids)
50                 return -ENODEV;
51
52         len = snprintf(modalias, size, "acpi:");
53         size -= len;
54
55         if (acpi_dev->flags.hardware_id) {
56                 count = snprintf(&modalias[len], size, "%s:",
57                                  acpi_dev->pnp.hardware_id);
58                 if (count < 0 || count >= size)
59                         return -EINVAL;
60                 len += count;
61                 size -= count;
62         }
63
64         if (acpi_dev->flags.compatible_ids) {
65                 struct acpica_device_id_list *cid_list;
66                 int i;
67
68                 cid_list = acpi_dev->pnp.cid_list;
69                 for (i = 0; i < cid_list->count; i++) {
70                         count = snprintf(&modalias[len], size, "%s:",
71                                          cid_list->ids[i].string);
72                         if (count < 0 || count >= size) {
73                                 printk(KERN_ERR PREFIX "%s cid[%i] exceeds event buffer size",
74                                        acpi_dev->pnp.device_name, i);
75                                 break;
76                         }
77                         len += count;
78                         size -= count;
79                 }
80         }
81
82         modalias[len] = '\0';
83         return len;
84 }
85
86 static ssize_t
87 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
88         struct acpi_device *acpi_dev = to_acpi_device(dev);
89         int len;
90
91         /* Device has no HID and no CID or string is >1024 */
92         len = create_modalias(acpi_dev, buf, 1024);
93         if (len <= 0)
94                 return 0;
95         buf[len++] = '\n';
96         return len;
97 }
98 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
99
100 static void acpi_bus_hot_remove_device(void *context)
101 {
102         struct acpi_device *device;
103         acpi_handle handle = context;
104         struct acpi_object_list arg_list;
105         union acpi_object arg;
106         acpi_status status = AE_OK;
107
108         if (acpi_bus_get_device(handle, &device))
109                 return;
110
111         if (!device)
112                 return;
113
114         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
115                 "Hot-removing device %s...\n", dev_name(&device->dev)));
116
117         if (acpi_bus_trim(device, 1)) {
118                 printk(KERN_ERR PREFIX
119                                 "Removing device failed\n");
120                 return;
121         }
122
123         /* power off device */
124         status = acpi_evaluate_object(handle, "_PS3", NULL, NULL);
125         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
126                 printk(KERN_WARNING PREFIX
127                                 "Power-off device failed\n");
128
129         if (device->flags.lockable) {
130                 arg_list.count = 1;
131                 arg_list.pointer = &arg;
132                 arg.type = ACPI_TYPE_INTEGER;
133                 arg.integer.value = 0;
134                 acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
135         }
136
137         arg_list.count = 1;
138         arg_list.pointer = &arg;
139         arg.type = ACPI_TYPE_INTEGER;
140         arg.integer.value = 1;
141
142         /*
143          * TBD: _EJD support.
144          */
145         status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
146         if (ACPI_FAILURE(status))
147                 printk(KERN_WARNING PREFIX
148                                 "Eject device failed\n");
149
150         return;
151 }
152
153 static ssize_t
154 acpi_eject_store(struct device *d, struct device_attribute *attr,
155                 const char *buf, size_t count)
156 {
157         int ret = count;
158         acpi_status status;
159         acpi_object_type type = 0;
160         struct acpi_device *acpi_device = to_acpi_device(d);
161
162         if ((!count) || (buf[0] != '1')) {
163                 return -EINVAL;
164         }
165 #ifndef FORCE_EJECT
166         if (acpi_device->driver == NULL) {
167                 ret = -ENODEV;
168                 goto err;
169         }
170 #endif
171         status = acpi_get_type(acpi_device->handle, &type);
172         if (ACPI_FAILURE(status) || (!acpi_device->flags.ejectable)) {
173                 ret = -ENODEV;
174                 goto err;
175         }
176
177         acpi_os_hotplug_execute(acpi_bus_hot_remove_device, acpi_device->handle);
178 err:
179         return ret;
180 }
181
182 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
183
184 static ssize_t
185 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
186         struct acpi_device *acpi_dev = to_acpi_device(dev);
187
188         return sprintf(buf, "%s\n", acpi_dev->pnp.hardware_id);
189 }
190 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
191
192 static ssize_t
193 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
194         struct acpi_device *acpi_dev = to_acpi_device(dev);
195         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
196         int result;
197
198         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
199         if (result)
200                 goto end;
201
202         result = sprintf(buf, "%s\n", (char*)path.pointer);
203         kfree(path.pointer);
204 end:
205         return result;
206 }
207 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
208
209 static int acpi_device_setup_files(struct acpi_device *dev)
210 {
211         acpi_status status;
212         acpi_handle temp;
213         int result = 0;
214
215         /*
216          * Devices gotten from FADT don't have a "path" attribute
217          */
218         if (dev->handle) {
219                 result = device_create_file(&dev->dev, &dev_attr_path);
220                 if (result)
221                         goto end;
222         }
223
224         if (dev->flags.hardware_id) {
225                 result = device_create_file(&dev->dev, &dev_attr_hid);
226                 if (result)
227                         goto end;
228         }
229
230         if (dev->flags.hardware_id || dev->flags.compatible_ids) {
231                 result = device_create_file(&dev->dev, &dev_attr_modalias);
232                 if (result)
233                         goto end;
234         }
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                 result = device_create_file(&dev->dev, &dev_attr_eject);
243 end:
244         return result;
245 }
246
247 static void acpi_device_remove_files(struct acpi_device *dev)
248 {
249         acpi_status status;
250         acpi_handle temp;
251
252         /*
253          * If device has _EJ0, 'eject' file is created that is used to trigger
254          * hot-removal function from userland.
255          */
256         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
257         if (ACPI_SUCCESS(status))
258                 device_remove_file(&dev->dev, &dev_attr_eject);
259
260         if (dev->flags.hardware_id || dev->flags.compatible_ids)
261                 device_remove_file(&dev->dev, &dev_attr_modalias);
262
263         if (dev->flags.hardware_id)
264                 device_remove_file(&dev->dev, &dev_attr_hid);
265         if (dev->handle)
266                 device_remove_file(&dev->dev, &dev_attr_path);
267 }
268 /* --------------------------------------------------------------------------
269                         ACPI Bus operations
270    -------------------------------------------------------------------------- */
271
272 int acpi_match_device_ids(struct acpi_device *device,
273                           const struct acpi_device_id *ids)
274 {
275         const struct acpi_device_id *id;
276
277         /*
278          * If the device is not present, it is unnecessary to load device
279          * driver for it.
280          */
281         if (!device->status.present)
282                 return -ENODEV;
283
284         if (device->flags.hardware_id) {
285                 for (id = ids; id->id[0]; id++) {
286                         if (!strcmp((char*)id->id, device->pnp.hardware_id))
287                                 return 0;
288                 }
289         }
290
291         if (device->flags.compatible_ids) {
292                 struct acpica_device_id_list *cid_list = device->pnp.cid_list;
293                 int i;
294
295                 for (id = ids; id->id[0]; id++) {
296                         /* compare multiple _CID entries against driver ids */
297                         for (i = 0; i < cid_list->count; i++) {
298                                 if (!strcmp((char*)id->id,
299                                             cid_list->ids[i].string))
300                                         return 0;
301                         }
302                 }
303         }
304
305         return -ENOENT;
306 }
307 EXPORT_SYMBOL(acpi_match_device_ids);
308
309 static void acpi_device_release(struct device *dev)
310 {
311         struct acpi_device *acpi_dev = to_acpi_device(dev);
312
313         kfree(acpi_dev->pnp.cid_list);
314         if (acpi_dev->flags.hardware_id)
315                 kfree(acpi_dev->pnp.hardware_id);
316         if (acpi_dev->flags.unique_id)
317                 kfree(acpi_dev->pnp.unique_id);
318         kfree(acpi_dev);
319 }
320
321 static int acpi_device_suspend(struct device *dev, pm_message_t state)
322 {
323         struct acpi_device *acpi_dev = to_acpi_device(dev);
324         struct acpi_driver *acpi_drv = acpi_dev->driver;
325
326         if (acpi_drv && acpi_drv->ops.suspend)
327                 return acpi_drv->ops.suspend(acpi_dev, state);
328         return 0;
329 }
330
331 static int acpi_device_resume(struct device *dev)
332 {
333         struct acpi_device *acpi_dev = to_acpi_device(dev);
334         struct acpi_driver *acpi_drv = acpi_dev->driver;
335
336         if (acpi_drv && acpi_drv->ops.resume)
337                 return acpi_drv->ops.resume(acpi_dev);
338         return 0;
339 }
340
341 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
342 {
343         struct acpi_device *acpi_dev = to_acpi_device(dev);
344         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
345
346         return !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
347 }
348
349 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
350 {
351         struct acpi_device *acpi_dev = to_acpi_device(dev);
352         int len;
353
354         if (add_uevent_var(env, "MODALIAS="))
355                 return -ENOMEM;
356         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
357                               sizeof(env->buf) - env->buflen);
358         if (len >= (sizeof(env->buf) - env->buflen))
359                 return -ENOMEM;
360         env->buflen += len;
361         return 0;
362 }
363
364 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
365 {
366         struct acpi_device *device = data;
367
368         device->driver->ops.notify(device, event);
369 }
370
371 static acpi_status acpi_device_notify_fixed(void *data)
372 {
373         struct acpi_device *device = data;
374
375         /* Fixed hardware devices have no handles */
376         acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
377         return AE_OK;
378 }
379
380 static int acpi_device_install_notify_handler(struct acpi_device *device)
381 {
382         acpi_status status;
383
384         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
385                 status =
386                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
387                                                      acpi_device_notify_fixed,
388                                                      device);
389         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
390                 status =
391                     acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
392                                                      acpi_device_notify_fixed,
393                                                      device);
394         else
395                 status = acpi_install_notify_handler(device->handle,
396                                                      ACPI_DEVICE_NOTIFY,
397                                                      acpi_device_notify,
398                                                      device);
399
400         if (ACPI_FAILURE(status))
401                 return -EINVAL;
402         return 0;
403 }
404
405 static void acpi_device_remove_notify_handler(struct acpi_device *device)
406 {
407         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
408                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
409                                                 acpi_device_notify_fixed);
410         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
411                 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
412                                                 acpi_device_notify_fixed);
413         else
414                 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
415                                            acpi_device_notify);
416 }
417
418 static int acpi_bus_driver_init(struct acpi_device *, struct acpi_driver *);
419 static int acpi_start_single_object(struct acpi_device *);
420 static int acpi_device_probe(struct device * dev)
421 {
422         struct acpi_device *acpi_dev = to_acpi_device(dev);
423         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
424         int ret;
425
426         ret = acpi_bus_driver_init(acpi_dev, acpi_drv);
427         if (!ret) {
428                 if (acpi_dev->bus_ops.acpi_op_start)
429                         acpi_start_single_object(acpi_dev);
430
431                 if (acpi_drv->ops.notify) {
432                         ret = acpi_device_install_notify_handler(acpi_dev);
433                         if (ret) {
434                                 if (acpi_drv->ops.remove)
435                                         acpi_drv->ops.remove(acpi_dev,
436                                                      acpi_dev->removal_type);
437                                 return ret;
438                         }
439                 }
440
441                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
442                         "Found driver [%s] for device [%s]\n",
443                         acpi_drv->name, acpi_dev->pnp.bus_id));
444                 get_device(dev);
445         }
446         return ret;
447 }
448
449 static int acpi_device_remove(struct device * dev)
450 {
451         struct acpi_device *acpi_dev = to_acpi_device(dev);
452         struct acpi_driver *acpi_drv = acpi_dev->driver;
453
454         if (acpi_drv) {
455                 if (acpi_drv->ops.notify)
456                         acpi_device_remove_notify_handler(acpi_dev);
457                 if (acpi_drv->ops.remove)
458                         acpi_drv->ops.remove(acpi_dev, acpi_dev->removal_type);
459         }
460         acpi_dev->driver = NULL;
461         acpi_dev->driver_data = NULL;
462
463         put_device(dev);
464         return 0;
465 }
466
467 struct bus_type acpi_bus_type = {
468         .name           = "acpi",
469         .suspend        = acpi_device_suspend,
470         .resume         = acpi_device_resume,
471         .match          = acpi_bus_match,
472         .probe          = acpi_device_probe,
473         .remove         = acpi_device_remove,
474         .uevent         = acpi_device_uevent,
475 };
476
477 static int acpi_device_register(struct acpi_device *device)
478 {
479         int result;
480         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
481         int found = 0;
482
483         /*
484          * Linkage
485          * -------
486          * Link this device to its parent and siblings.
487          */
488         INIT_LIST_HEAD(&device->children);
489         INIT_LIST_HEAD(&device->node);
490         INIT_LIST_HEAD(&device->wakeup_list);
491
492         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
493         if (!new_bus_id) {
494                 printk(KERN_ERR PREFIX "Memory allocation error\n");
495                 return -ENOMEM;
496         }
497
498         mutex_lock(&acpi_device_lock);
499         /*
500          * Find suitable bus_id and instance number in acpi_bus_id_list
501          * If failed, create one and link it into acpi_bus_id_list
502          */
503         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
504                 if(!strcmp(acpi_device_bus_id->bus_id, device->flags.hardware_id? device->pnp.hardware_id : "device")) {
505                         acpi_device_bus_id->instance_no ++;
506                         found = 1;
507                         kfree(new_bus_id);
508                         break;
509                 }
510         }
511         if (!found) {
512                 acpi_device_bus_id = new_bus_id;
513                 strcpy(acpi_device_bus_id->bus_id, device->flags.hardware_id ? device->pnp.hardware_id : "device");
514                 acpi_device_bus_id->instance_no = 0;
515                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
516         }
517         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
518
519         if (device->parent)
520                 list_add_tail(&device->node, &device->parent->children);
521
522         if (device->wakeup.flags.valid)
523                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
524         mutex_unlock(&acpi_device_lock);
525
526         if (device->parent)
527                 device->dev.parent = &device->parent->dev;
528         device->dev.bus = &acpi_bus_type;
529         device->dev.release = &acpi_device_release;
530         result = device_register(&device->dev);
531         if (result) {
532                 dev_err(&device->dev, "Error registering device\n");
533                 goto end;
534         }
535
536         result = acpi_device_setup_files(device);
537         if (result)
538                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
539                        dev_name(&device->dev));
540
541         device->removal_type = ACPI_BUS_REMOVAL_NORMAL;
542         return 0;
543 end:
544         mutex_lock(&acpi_device_lock);
545         if (device->parent)
546                 list_del(&device->node);
547         list_del(&device->wakeup_list);
548         mutex_unlock(&acpi_device_lock);
549         return result;
550 }
551
552 static void acpi_device_unregister(struct acpi_device *device, int type)
553 {
554         mutex_lock(&acpi_device_lock);
555         if (device->parent)
556                 list_del(&device->node);
557
558         list_del(&device->wakeup_list);
559         mutex_unlock(&acpi_device_lock);
560
561         acpi_detach_data(device->handle, acpi_bus_data_handler);
562
563         acpi_device_remove_files(device);
564         device_unregister(&device->dev);
565 }
566
567 /* --------------------------------------------------------------------------
568                                  Driver Management
569    -------------------------------------------------------------------------- */
570 /**
571  * acpi_bus_driver_init - add a device to a driver
572  * @device: the device to add and initialize
573  * @driver: driver for the device
574  *
575  * Used to initialize a device via its device driver.  Called whenever a
576  * driver is bound to a device.  Invokes the driver's add() ops.
577  */
578 static int
579 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
580 {
581         int result = 0;
582
583         if (!device || !driver)
584                 return -EINVAL;
585
586         if (!driver->ops.add)
587                 return -ENOSYS;
588
589         result = driver->ops.add(device);
590         if (result) {
591                 device->driver = NULL;
592                 device->driver_data = NULL;
593                 return result;
594         }
595
596         device->driver = driver;
597
598         /*
599          * TBD - Configuration Management: Assign resources to device based
600          * upon possible configuration and currently allocated resources.
601          */
602
603         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
604                           "Driver successfully bound to device\n"));
605         return 0;
606 }
607
608 static int acpi_start_single_object(struct acpi_device *device)
609 {
610         int result = 0;
611         struct acpi_driver *driver;
612
613
614         if (!(driver = device->driver))
615                 return 0;
616
617         if (driver->ops.start) {
618                 result = driver->ops.start(device);
619                 if (result && driver->ops.remove)
620                         driver->ops.remove(device, ACPI_BUS_REMOVAL_NORMAL);
621         }
622
623         return result;
624 }
625
626 /**
627  * acpi_bus_register_driver - register a driver with the ACPI bus
628  * @driver: driver being registered
629  *
630  * Registers a driver with the ACPI bus.  Searches the namespace for all
631  * devices that match the driver's criteria and binds.  Returns zero for
632  * success or a negative error status for failure.
633  */
634 int acpi_bus_register_driver(struct acpi_driver *driver)
635 {
636         int ret;
637
638         if (acpi_disabled)
639                 return -ENODEV;
640         driver->drv.name = driver->name;
641         driver->drv.bus = &acpi_bus_type;
642         driver->drv.owner = driver->owner;
643
644         ret = driver_register(&driver->drv);
645         return ret;
646 }
647
648 EXPORT_SYMBOL(acpi_bus_register_driver);
649
650 /**
651  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
652  * @driver: driver to unregister
653  *
654  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
655  * devices that match the driver's criteria and unbinds.
656  */
657 void acpi_bus_unregister_driver(struct acpi_driver *driver)
658 {
659         driver_unregister(&driver->drv);
660 }
661
662 EXPORT_SYMBOL(acpi_bus_unregister_driver);
663
664 /* --------------------------------------------------------------------------
665                                  Device Enumeration
666    -------------------------------------------------------------------------- */
667 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
668 {
669         acpi_status status;
670         int ret;
671         struct acpi_device *device;
672
673         /*
674          * Fixed hardware devices do not appear in the namespace and do not
675          * have handles, but we fabricate acpi_devices for them, so we have
676          * to deal with them specially.
677          */
678         if (handle == NULL)
679                 return acpi_root;
680
681         do {
682                 status = acpi_get_parent(handle, &handle);
683                 if (status == AE_NULL_ENTRY)
684                         return NULL;
685                 if (ACPI_FAILURE(status))
686                         return acpi_root;
687
688                 ret = acpi_bus_get_device(handle, &device);
689                 if (ret == 0)
690                         return device;
691         } while (1);
692 }
693
694 acpi_status
695 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
696 {
697         acpi_status status;
698         acpi_handle tmp;
699         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
700         union acpi_object *obj;
701
702         status = acpi_get_handle(handle, "_EJD", &tmp);
703         if (ACPI_FAILURE(status))
704                 return status;
705
706         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
707         if (ACPI_SUCCESS(status)) {
708                 obj = buffer.pointer;
709                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
710                                          ejd);
711                 kfree(buffer.pointer);
712         }
713         return status;
714 }
715 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
716
717 void acpi_bus_data_handler(acpi_handle handle, void *context)
718 {
719
720         /* TBD */
721
722         return;
723 }
724
725 static int acpi_bus_get_perf_flags(struct acpi_device *device)
726 {
727         device->performance.state = ACPI_STATE_UNKNOWN;
728         return 0;
729 }
730
731 static acpi_status
732 acpi_bus_extract_wakeup_device_power_package(struct acpi_device *device,
733                                              union acpi_object *package)
734 {
735         int i = 0;
736         union acpi_object *element = NULL;
737
738         if (!device || !package || (package->package.count < 2))
739                 return AE_BAD_PARAMETER;
740
741         element = &(package->package.elements[0]);
742         if (!element)
743                 return AE_BAD_PARAMETER;
744         if (element->type == ACPI_TYPE_PACKAGE) {
745                 if ((element->package.count < 2) ||
746                     (element->package.elements[0].type !=
747                      ACPI_TYPE_LOCAL_REFERENCE)
748                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
749                         return AE_BAD_DATA;
750                 device->wakeup.gpe_device =
751                     element->package.elements[0].reference.handle;
752                 device->wakeup.gpe_number =
753                     (u32) element->package.elements[1].integer.value;
754         } else if (element->type == ACPI_TYPE_INTEGER) {
755                 device->wakeup.gpe_number = element->integer.value;
756         } else
757                 return AE_BAD_DATA;
758
759         element = &(package->package.elements[1]);
760         if (element->type != ACPI_TYPE_INTEGER) {
761                 return AE_BAD_DATA;
762         }
763         device->wakeup.sleep_state = element->integer.value;
764
765         if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
766                 return AE_NO_MEMORY;
767         }
768         device->wakeup.resources.count = package->package.count - 2;
769         for (i = 0; i < device->wakeup.resources.count; i++) {
770                 element = &(package->package.elements[i + 2]);
771                 if (element->type != ACPI_TYPE_LOCAL_REFERENCE)
772                         return AE_BAD_DATA;
773
774                 device->wakeup.resources.handles[i] = element->reference.handle;
775         }
776
777         return AE_OK;
778 }
779
780 static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
781 {
782         acpi_status status = 0;
783         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
784         union acpi_object *package = NULL;
785         int psw_error;
786
787         struct acpi_device_id button_device_ids[] = {
788                 {"PNP0C0D", 0},
789                 {"PNP0C0C", 0},
790                 {"PNP0C0E", 0},
791                 {"", 0},
792         };
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         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
813          * system for the ACPI device with the _PRW object.
814          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
815          * So it is necessary to call _DSW object first. Only when it is not
816          * present will the _PSW object used.
817          */
818         psw_error = acpi_device_sleep_wake(device, 0, 0, 0);
819         if (psw_error)
820                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
821                                 "error in _DSW or _PSW evaluation\n"));
822
823         /* Power button, Lid switch always enable wakeup */
824         if (!acpi_match_device_ids(device, button_device_ids))
825                 device->wakeup.flags.run_wake = 1;
826
827 end:
828         if (ACPI_FAILURE(status))
829                 device->flags.wake_capable = 0;
830         return 0;
831 }
832
833 static int acpi_bus_get_power_flags(struct acpi_device *device)
834 {
835         acpi_status status = 0;
836         acpi_handle handle = NULL;
837         u32 i = 0;
838
839
840         /*
841          * Power Management Flags
842          */
843         status = acpi_get_handle(device->handle, "_PSC", &handle);
844         if (ACPI_SUCCESS(status))
845                 device->power.flags.explicit_get = 1;
846         status = acpi_get_handle(device->handle, "_IRC", &handle);
847         if (ACPI_SUCCESS(status))
848                 device->power.flags.inrush_current = 1;
849
850         /*
851          * Enumerate supported power management states
852          */
853         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
854                 struct acpi_device_power_state *ps = &device->power.states[i];
855                 char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
856
857                 /* Evaluate "_PRx" to se if power resources are referenced */
858                 acpi_evaluate_reference(device->handle, object_name, NULL,
859                                         &ps->resources);
860                 if (ps->resources.count) {
861                         device->power.flags.power_resources = 1;
862                         ps->flags.valid = 1;
863                 }
864
865                 /* Evaluate "_PSx" to see if we can do explicit sets */
866                 object_name[2] = 'S';
867                 status = acpi_get_handle(device->handle, object_name, &handle);
868                 if (ACPI_SUCCESS(status)) {
869                         ps->flags.explicit_set = 1;
870                         ps->flags.valid = 1;
871                 }
872
873                 /* State is valid if we have some power control */
874                 if (ps->resources.count || ps->flags.explicit_set)
875                         ps->flags.valid = 1;
876
877                 ps->power = -1; /* Unknown - driver assigned */
878                 ps->latency = -1;       /* Unknown - driver assigned */
879         }
880
881         /* Set defaults for D0 and D3 states (always valid) */
882         device->power.states[ACPI_STATE_D0].flags.valid = 1;
883         device->power.states[ACPI_STATE_D0].power = 100;
884         device->power.states[ACPI_STATE_D3].flags.valid = 1;
885         device->power.states[ACPI_STATE_D3].power = 0;
886
887         /* TBD: System wake support and resource requirements. */
888
889         device->power.state = ACPI_STATE_UNKNOWN;
890         acpi_bus_get_power(device->handle, &(device->power.state));
891
892         return 0;
893 }
894
895 static int acpi_bus_get_flags(struct acpi_device *device)
896 {
897         acpi_status status = AE_OK;
898         acpi_handle temp = NULL;
899
900
901         /* Presence of _STA indicates 'dynamic_status' */
902         status = acpi_get_handle(device->handle, "_STA", &temp);
903         if (ACPI_SUCCESS(status))
904                 device->flags.dynamic_status = 1;
905
906         /* Presence of _CID indicates 'compatible_ids' */
907         status = acpi_get_handle(device->handle, "_CID", &temp);
908         if (ACPI_SUCCESS(status))
909                 device->flags.compatible_ids = 1;
910
911         /* Presence of _RMV indicates 'removable' */
912         status = acpi_get_handle(device->handle, "_RMV", &temp);
913         if (ACPI_SUCCESS(status))
914                 device->flags.removable = 1;
915
916         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
917         status = acpi_get_handle(device->handle, "_EJD", &temp);
918         if (ACPI_SUCCESS(status))
919                 device->flags.ejectable = 1;
920         else {
921                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
922                 if (ACPI_SUCCESS(status))
923                         device->flags.ejectable = 1;
924         }
925
926         /* Presence of _LCK indicates 'lockable' */
927         status = acpi_get_handle(device->handle, "_LCK", &temp);
928         if (ACPI_SUCCESS(status))
929                 device->flags.lockable = 1;
930
931         /* Presence of _PS0|_PR0 indicates 'power manageable' */
932         status = acpi_get_handle(device->handle, "_PS0", &temp);
933         if (ACPI_FAILURE(status))
934                 status = acpi_get_handle(device->handle, "_PR0", &temp);
935         if (ACPI_SUCCESS(status))
936                 device->flags.power_manageable = 1;
937
938         /* Presence of _PRW indicates wake capable */
939         status = acpi_get_handle(device->handle, "_PRW", &temp);
940         if (ACPI_SUCCESS(status))
941                 device->flags.wake_capable = 1;
942
943         /* TBD: Performance management */
944
945         return 0;
946 }
947
948 static void acpi_device_get_busid(struct acpi_device *device)
949 {
950         char bus_id[5] = { '?', 0 };
951         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
952         int i = 0;
953
954         /*
955          * Bus ID
956          * ------
957          * The device's Bus ID is simply the object name.
958          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
959          */
960         if (ACPI_IS_ROOT_DEVICE(device)) {
961                 strcpy(device->pnp.bus_id, "ACPI");
962                 return;
963         }
964
965         switch (device->device_type) {
966         case ACPI_BUS_TYPE_POWER_BUTTON:
967                 strcpy(device->pnp.bus_id, "PWRF");
968                 break;
969         case ACPI_BUS_TYPE_SLEEP_BUTTON:
970                 strcpy(device->pnp.bus_id, "SLPF");
971                 break;
972         default:
973                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
974                 /* Clean up trailing underscores (if any) */
975                 for (i = 3; i > 1; i--) {
976                         if (bus_id[i] == '_')
977                                 bus_id[i] = '\0';
978                         else
979                                 break;
980                 }
981                 strcpy(device->pnp.bus_id, bus_id);
982                 break;
983         }
984 }
985
986 /*
987  * acpi_bay_match - see if a device is an ejectable driver bay
988  *
989  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
990  * then we can safely call it an ejectable drive bay
991  */
992 static int acpi_bay_match(struct acpi_device *device){
993         acpi_status status;
994         acpi_handle handle;
995         acpi_handle tmp;
996         acpi_handle phandle;
997
998         handle = device->handle;
999
1000         status = acpi_get_handle(handle, "_EJ0", &tmp);
1001         if (ACPI_FAILURE(status))
1002                 return -ENODEV;
1003
1004         if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
1005                 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
1006                 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
1007                 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
1008                 return 0;
1009
1010         if (acpi_get_parent(handle, &phandle))
1011                 return -ENODEV;
1012
1013         if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
1014                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
1015                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
1016                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
1017                 return 0;
1018
1019         return -ENODEV;
1020 }
1021
1022 /*
1023  * acpi_dock_match - see if a device has a _DCK method
1024  */
1025 static int acpi_dock_match(struct acpi_device *device)
1026 {
1027         acpi_handle tmp;
1028         return acpi_get_handle(device->handle, "_DCK", &tmp);
1029 }
1030
1031 static struct acpica_device_id_list*
1032 acpi_add_cid(
1033         struct acpi_device_info         *info,
1034         struct acpica_device_id         *new_cid)
1035 {
1036         struct acpica_device_id_list    *cid;
1037         char                            *next_id_string;
1038         acpi_size                       cid_length;
1039         acpi_size                       new_cid_length;
1040         u32                             i;
1041
1042
1043         /* Allocate new CID list with room for the new CID */
1044
1045         if (!new_cid)
1046                 new_cid_length = info->compatible_id_list.list_size;
1047         else if (info->compatible_id_list.list_size)
1048                 new_cid_length = info->compatible_id_list.list_size +
1049                         new_cid->length + sizeof(struct acpica_device_id);
1050         else
1051                 new_cid_length = sizeof(struct acpica_device_id_list) + new_cid->length;
1052
1053         cid = ACPI_ALLOCATE_ZEROED(new_cid_length);
1054         if (!cid) {
1055                 return NULL;
1056         }
1057
1058         cid->list_size = new_cid_length;
1059         cid->count = info->compatible_id_list.count;
1060         if (new_cid)
1061                 cid->count++;
1062         next_id_string = (char *) cid->ids + (cid->count * sizeof(struct acpica_device_id));
1063
1064         /* Copy all existing CIDs */
1065
1066         for (i = 0; i < info->compatible_id_list.count; i++) {
1067                 cid_length = info->compatible_id_list.ids[i].length;
1068                 cid->ids[i].string = next_id_string;
1069                 cid->ids[i].length = cid_length;
1070
1071                 ACPI_MEMCPY(next_id_string, info->compatible_id_list.ids[i].string,
1072                         cid_length);
1073
1074                 next_id_string += cid_length;
1075         }
1076
1077         /* Append the new CID */
1078
1079         if (new_cid) {
1080                 cid->ids[i].string = next_id_string;
1081                 cid->ids[i].length = new_cid->length;
1082
1083                 ACPI_MEMCPY(next_id_string, new_cid->string, new_cid->length);
1084         }
1085
1086         return cid;
1087 }
1088
1089 static void acpi_device_set_id(struct acpi_device *device)
1090 {
1091         struct acpi_device_info *info = NULL;
1092         char *hid = NULL;
1093         char *uid = NULL;
1094         struct acpica_device_id_list *cid_list = NULL;
1095         char *cid_add = NULL;
1096         acpi_status status;
1097
1098         switch (device->device_type) {
1099         case ACPI_BUS_TYPE_DEVICE:
1100                 if (ACPI_IS_ROOT_DEVICE(device)) {
1101                         hid = ACPI_SYSTEM_HID;
1102                         break;
1103                 }
1104
1105                 status = acpi_get_object_info(device->handle, &info);
1106                 if (ACPI_FAILURE(status)) {
1107                         printk(KERN_ERR PREFIX "%s: Error reading device info\n", __func__);
1108                         return;
1109                 }
1110
1111                 if (info->valid & ACPI_VALID_HID)
1112                         hid = info->hardware_id.string;
1113                 if (info->valid & ACPI_VALID_UID)
1114                         uid = info->unique_id.string;
1115                 if (info->valid & ACPI_VALID_CID)
1116                         cid_list = &info->compatible_id_list;
1117                 if (info->valid & ACPI_VALID_ADR) {
1118                         device->pnp.bus_address = info->address;
1119                         device->flags.bus_address = 1;
1120                 }
1121
1122                 /* If we have a video/bay/dock device, add our selfdefined
1123                    HID to the CID list. Like that the video/bay/dock drivers
1124                    will get autoloaded and the device might still match
1125                    against another driver.
1126                 */
1127                 if (acpi_is_video_device(device))
1128                         cid_add = ACPI_VIDEO_HID;
1129                 else if (ACPI_SUCCESS(acpi_bay_match(device)))
1130                         cid_add = ACPI_BAY_HID;
1131                 else if (ACPI_SUCCESS(acpi_dock_match(device)))
1132                         cid_add = ACPI_DOCK_HID;
1133
1134                 break;
1135         case ACPI_BUS_TYPE_POWER:
1136                 hid = ACPI_POWER_HID;
1137                 break;
1138         case ACPI_BUS_TYPE_PROCESSOR:
1139                 hid = ACPI_PROCESSOR_OBJECT_HID;
1140                 break;
1141         case ACPI_BUS_TYPE_THERMAL:
1142                 hid = ACPI_THERMAL_HID;
1143                 break;
1144         case ACPI_BUS_TYPE_POWER_BUTTON:
1145                 hid = ACPI_BUTTON_HID_POWERF;
1146                 break;
1147         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1148                 hid = ACPI_BUTTON_HID_SLEEPF;
1149                 break;
1150         }
1151
1152         /*
1153          * \_SB
1154          * ----
1155          * Fix for the system root bus device -- the only root-level device.
1156          */
1157         if (((acpi_handle)device->parent == ACPI_ROOT_OBJECT) &&
1158              (device->device_type == ACPI_BUS_TYPE_DEVICE)) {
1159                 hid = ACPI_BUS_HID;
1160                 strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
1161                 strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
1162         }
1163
1164         if (hid) {
1165                 device->pnp.hardware_id = ACPI_ALLOCATE_ZEROED(strlen (hid) + 1);
1166                 if (device->pnp.hardware_id) {
1167                         strcpy(device->pnp.hardware_id, hid);
1168                         device->flags.hardware_id = 1;
1169                 }
1170         }
1171         if (!device->flags.hardware_id)
1172                 device->pnp.hardware_id = "";
1173
1174         if (uid) {
1175                 device->pnp.unique_id = ACPI_ALLOCATE_ZEROED(strlen (uid) + 1);
1176                 if (device->pnp.unique_id) {
1177                         strcpy(device->pnp.unique_id, uid);
1178                         device->flags.unique_id = 1;
1179                 }
1180         }
1181         if (!device->flags.unique_id)
1182                 device->pnp.unique_id = "";
1183
1184         if (cid_list || cid_add) {
1185                 struct acpica_device_id_list *list;
1186
1187                 if (cid_add) {
1188                         struct acpica_device_id cid;
1189                         cid.length = strlen (cid_add) + 1;
1190                         cid.string = cid_add;
1191
1192                         list = acpi_add_cid(info, &cid);
1193                 } else {
1194                         list = acpi_add_cid(info, NULL);
1195                 }
1196
1197                 if (list) {
1198                         device->pnp.cid_list = list;
1199                         if (cid_add)
1200                                 device->flags.compatible_ids = 1;
1201                 }
1202         }
1203
1204         kfree(info);
1205 }
1206
1207 static int acpi_device_set_context(struct acpi_device *device)
1208 {
1209         acpi_status status;
1210
1211         /*
1212          * Context
1213          * -------
1214          * Attach this 'struct acpi_device' to the ACPI object.  This makes
1215          * resolutions from handle->device very efficient.  Fixed hardware
1216          * devices have no handles, so we skip them.
1217          */
1218         if (!device->handle)
1219                 return 0;
1220
1221         status = acpi_attach_data(device->handle,
1222                                   acpi_bus_data_handler, device);
1223         if (ACPI_SUCCESS(status))
1224                 return 0;
1225
1226         printk(KERN_ERR PREFIX "Error attaching device data\n");
1227         return -ENODEV;
1228 }
1229
1230 static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
1231 {
1232         if (!dev)
1233                 return -EINVAL;
1234
1235         dev->removal_type = ACPI_BUS_REMOVAL_EJECT;
1236         device_release_driver(&dev->dev);
1237
1238         if (!rmdevice)
1239                 return 0;
1240
1241         /*
1242          * unbind _ADR-Based Devices when hot removal
1243          */
1244         if (dev->flags.bus_address) {
1245                 if ((dev->parent) && (dev->parent->ops.unbind))
1246                         dev->parent->ops.unbind(dev);
1247         }
1248         acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
1249
1250         return 0;
1251 }
1252
1253 static int acpi_add_single_object(struct acpi_device **child,
1254                                   acpi_handle handle, int type,
1255                                   struct acpi_bus_ops *ops)
1256 {
1257         int result;
1258         struct acpi_device *device;
1259         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1260
1261         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1262         if (!device) {
1263                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1264                 return -ENOMEM;
1265         }
1266
1267         device->device_type = type;
1268         device->handle = handle;
1269         device->parent = acpi_bus_get_parent(handle);
1270         device->bus_ops = *ops; /* workround for not call .start */
1271
1272         acpi_device_get_busid(device);
1273
1274         /*
1275          * Flags
1276          * -----
1277          * Get prior to calling acpi_bus_get_status() so we know whether
1278          * or not _STA is present.  Note that we only look for object
1279          * handles -- cannot evaluate objects until we know the device is
1280          * present and properly initialized.
1281          */
1282         result = acpi_bus_get_flags(device);
1283         if (result)
1284                 goto end;
1285
1286         /*
1287          * Status
1288          * ------
1289          * See if the device is present.  We always assume that non-Device
1290          * and non-Processor objects (e.g. thermal zones, power resources,
1291          * etc.) are present, functioning, etc. (at least when parent object
1292          * is present).  Note that _STA has a different meaning for some
1293          * objects (e.g. power resources) so we need to be careful how we use
1294          * it.
1295          */
1296         switch (type) {
1297         case ACPI_BUS_TYPE_PROCESSOR:
1298         case ACPI_BUS_TYPE_DEVICE:
1299                 result = acpi_bus_get_status(device);
1300                 if (ACPI_FAILURE(result)) {
1301                         result = -ENODEV;
1302                         goto end;
1303                 }
1304                 /*
1305                  * When the device is neither present nor functional, the
1306                  * device should not be added to Linux ACPI device tree.
1307                  * When the status of the device is not present but functinal,
1308                  * it should be added to Linux ACPI tree. For example : bay
1309                  * device , dock device.
1310                  * In such conditions it is unncessary to check whether it is
1311                  * bay device or dock device.
1312                  */
1313                 if (!device->status.present && !device->status.functional) {
1314                         result = -ENODEV;
1315                         goto end;
1316                 }
1317                 break;
1318         default:
1319                 STRUCT_TO_INT(device->status) =
1320                     ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED |
1321                     ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING;
1322                 break;
1323         }
1324
1325         /*
1326          * Initialize Device
1327          * -----------------
1328          * TBD: Synch with Core's enumeration/initialization process.
1329          */
1330
1331         /*
1332          * Hardware ID, Unique ID, & Bus Address
1333          * -------------------------------------
1334          */
1335         acpi_device_set_id(device);
1336
1337         /*
1338          * Power Management
1339          * ----------------
1340          */
1341         if (device->flags.power_manageable) {
1342                 result = acpi_bus_get_power_flags(device);
1343                 if (result)
1344                         goto end;
1345         }
1346
1347         /*
1348          * Wakeup device management
1349          *-----------------------
1350          */
1351         if (device->flags.wake_capable) {
1352                 result = acpi_bus_get_wakeup_device_flags(device);
1353                 if (result)
1354                         goto end;
1355         }
1356
1357         /*
1358          * Performance Management
1359          * ----------------------
1360          */
1361         if (device->flags.performance_manageable) {
1362                 result = acpi_bus_get_perf_flags(device);
1363                 if (result)
1364                         goto end;
1365         }
1366
1367         if ((result = acpi_device_set_context(device)))
1368                 goto end;
1369
1370         result = acpi_device_register(device);
1371
1372         /*
1373          * Bind _ADR-Based Devices when hot add
1374          */
1375         if (device->flags.bus_address) {
1376                 if (device->parent && device->parent->ops.bind)
1377                         device->parent->ops.bind(device);
1378         }
1379
1380 end:
1381         if (!result) {
1382                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1383                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1384                         "Adding %s [%s] parent %s\n", dev_name(&device->dev),
1385                          (char *) buffer.pointer,
1386                          device->parent ? dev_name(&device->parent->dev) :
1387                                           "(null)"));
1388                 kfree(buffer.pointer);
1389                 *child = device;
1390         } else
1391                 acpi_device_release(&device->dev);
1392
1393         return result;
1394 }
1395
1396 static int acpi_bus_scan(acpi_handle handle, struct acpi_bus_ops *ops)
1397 {
1398         acpi_status status = AE_OK;
1399         struct acpi_device *parent = NULL;
1400         struct acpi_device *child = NULL;
1401         acpi_handle phandle = NULL;
1402         acpi_handle chandle = NULL;
1403         acpi_object_type type = 0;
1404         u32 level = 1;
1405         int ret;
1406
1407         /*
1408          * We must have an acpi_device for the starting node already, and
1409          * we scan its children.
1410          */
1411         phandle = handle;
1412         ret = acpi_bus_get_device(phandle, &parent);
1413         if (ret)
1414                 return ret;
1415
1416         /*
1417          * Parse through the ACPI namespace, identify all 'devices', and
1418          * create a new 'struct acpi_device' for each.
1419          */
1420         while ((level > 0) && parent) {
1421
1422                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1423                                               chandle, &chandle);
1424
1425                 /*
1426                  * If this scope is exhausted then move our way back up.
1427                  */
1428                 if (ACPI_FAILURE(status)) {
1429                         level--;
1430                         chandle = phandle;
1431                         acpi_get_parent(phandle, &phandle);
1432                         if (parent->parent)
1433                                 parent = parent->parent;
1434                         continue;
1435                 }
1436
1437                 status = acpi_get_type(chandle, &type);
1438                 if (ACPI_FAILURE(status))
1439                         continue;
1440
1441                 /*
1442                  * If this is a scope object then parse it (depth-first).
1443                  */
1444                 if (type == ACPI_TYPE_LOCAL_SCOPE) {
1445                         level++;
1446                         phandle = chandle;
1447                         chandle = NULL;
1448                         continue;
1449                 }
1450
1451                 /*
1452                  * We're only interested in objects that we consider 'devices'.
1453                  */
1454                 switch (type) {
1455                 case ACPI_TYPE_DEVICE:
1456                         type = ACPI_BUS_TYPE_DEVICE;
1457                         break;
1458                 case ACPI_TYPE_PROCESSOR:
1459                         type = ACPI_BUS_TYPE_PROCESSOR;
1460                         break;
1461                 case ACPI_TYPE_THERMAL:
1462                         type = ACPI_BUS_TYPE_THERMAL;
1463                         break;
1464                 case ACPI_TYPE_POWER:
1465                         type = ACPI_BUS_TYPE_POWER;
1466                         break;
1467                 default:
1468                         continue;
1469                 }
1470
1471                 if (ops->acpi_op_add)
1472                         status = acpi_add_single_object(&child, chandle, type,
1473                                                         ops);
1474                 else
1475                         status = acpi_bus_get_device(chandle, &child);
1476
1477                 if (ACPI_FAILURE(status))
1478                         continue;
1479
1480                 if (ops->acpi_op_start && !(ops->acpi_op_add)) {
1481                         status = acpi_start_single_object(child);
1482                         if (ACPI_FAILURE(status))
1483                                 continue;
1484                 }
1485
1486                 /*
1487                  * If the device is present, enabled, and functioning then
1488                  * parse its scope (depth-first).  Note that we need to
1489                  * represent absent devices to facilitate PnP notifications
1490                  * -- but only the subtree head (not all of its children,
1491                  * which will be enumerated when the parent is inserted).
1492                  *
1493                  * TBD: Need notifications and other detection mechanisms
1494                  *      in place before we can fully implement this.
1495                  */
1496                  /*
1497                  * When the device is not present but functional, it is also
1498                  * necessary to scan the children of this device.
1499                  */
1500                 if (child->status.present || (!child->status.present &&
1501                                         child->status.functional)) {
1502                         status = acpi_get_next_object(ACPI_TYPE_ANY, chandle,
1503                                                       NULL, NULL);
1504                         if (ACPI_SUCCESS(status)) {
1505                                 level++;
1506                                 phandle = chandle;
1507                                 chandle = NULL;
1508                                 parent = child;
1509                         }
1510                 }
1511         }
1512
1513         return 0;
1514 }
1515
1516 int
1517 acpi_bus_add(struct acpi_device **child,
1518              struct acpi_device *parent, acpi_handle handle, int type)
1519 {
1520         int result;
1521         struct acpi_bus_ops ops;
1522
1523         memset(&ops, 0, sizeof(ops));
1524         ops.acpi_op_add = 1;
1525
1526         result = acpi_add_single_object(child, handle, type, &ops);
1527         if (!result)
1528                 result = acpi_bus_scan((*child)->handle, &ops);
1529
1530         return result;
1531 }
1532 EXPORT_SYMBOL(acpi_bus_add);
1533
1534 int acpi_bus_start(struct acpi_device *device)
1535 {
1536         int result;
1537         struct acpi_bus_ops ops;
1538
1539         memset(&ops, 0, sizeof(ops));
1540         ops.acpi_op_start = 1;
1541
1542         result = acpi_start_single_object(device);
1543         if (!result)
1544                 result = acpi_bus_scan(device->handle, &ops);
1545
1546         return result;
1547 }
1548 EXPORT_SYMBOL(acpi_bus_start);
1549
1550 int acpi_bus_trim(struct acpi_device *start, int rmdevice)
1551 {
1552         acpi_status status;
1553         struct acpi_device *parent, *child;
1554         acpi_handle phandle, chandle;
1555         acpi_object_type type;
1556         u32 level = 1;
1557         int err = 0;
1558
1559         parent = start;
1560         phandle = start->handle;
1561         child = chandle = NULL;
1562
1563         while ((level > 0) && parent && (!err)) {
1564                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1565                                               chandle, &chandle);
1566
1567                 /*
1568                  * If this scope is exhausted then move our way back up.
1569                  */
1570                 if (ACPI_FAILURE(status)) {
1571                         level--;
1572                         chandle = phandle;
1573                         acpi_get_parent(phandle, &phandle);
1574                         child = parent;
1575                         parent = parent->parent;
1576
1577                         if (level == 0)
1578                                 err = acpi_bus_remove(child, rmdevice);
1579                         else
1580                                 err = acpi_bus_remove(child, 1);
1581
1582                         continue;
1583                 }
1584
1585                 status = acpi_get_type(chandle, &type);
1586                 if (ACPI_FAILURE(status)) {
1587                         continue;
1588                 }
1589                 /*
1590                  * If there is a device corresponding to chandle then
1591                  * parse it (depth-first).
1592                  */
1593                 if (acpi_bus_get_device(chandle, &child) == 0) {
1594                         level++;
1595                         phandle = chandle;
1596                         chandle = NULL;
1597                         parent = child;
1598                 }
1599                 continue;
1600         }
1601         return err;
1602 }
1603 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1604
1605 static int acpi_bus_scan_fixed(void)
1606 {
1607         int result = 0;
1608         struct acpi_device *device = NULL;
1609         struct acpi_bus_ops ops;
1610
1611         memset(&ops, 0, sizeof(ops));
1612         ops.acpi_op_add = 1;
1613         ops.acpi_op_start = 1;
1614
1615         /*
1616          * Enumerate all fixed-feature devices.
1617          */
1618         if ((acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON) == 0) {
1619                 result = acpi_add_single_object(&device, NULL,
1620                                                 ACPI_BUS_TYPE_POWER_BUTTON,
1621                                                 &ops);
1622         }
1623
1624         if ((acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON) == 0) {
1625                 result = acpi_add_single_object(&device, NULL,
1626                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
1627                                                 &ops);
1628         }
1629
1630         return result;
1631 }
1632
1633 int __init acpi_scan_init(void)
1634 {
1635         int result;
1636         struct acpi_bus_ops ops;
1637
1638         memset(&ops, 0, sizeof(ops));
1639         ops.acpi_op_add = 1;
1640         ops.acpi_op_start = 1;
1641
1642         result = bus_register(&acpi_bus_type);
1643         if (result) {
1644                 /* We don't want to quit even if we failed to add suspend/resume */
1645                 printk(KERN_ERR PREFIX "Could not register bus type\n");
1646         }
1647
1648         /*
1649          * Create the root device in the bus's device tree
1650          */
1651         result = acpi_add_single_object(&acpi_root, ACPI_ROOT_OBJECT,
1652                                         ACPI_BUS_TYPE_DEVICE, &ops);
1653         if (result)
1654                 goto Done;
1655
1656         /*
1657          * Enumerate devices in the ACPI namespace.
1658          */
1659         result = acpi_bus_scan(acpi_root->handle, &ops);
1660
1661         if (!result)
1662                 result = acpi_bus_scan_fixed();
1663
1664         if (result)
1665                 acpi_device_unregister(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
1666
1667 Done:
1668         return result;
1669 }