698a1540e3033ce1960d4c72a45f3a8177397d94
[linux-2.6.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/kernel.h>
8 #include <linux/acpi.h>
9
10 #include <acpi/acpi_drivers.h>
11 #include <acpi/acinterp.h>      /* for acpi_ex_eisa_id_to_string() */
12
13 #define _COMPONENT              ACPI_BUS_COMPONENT
14 ACPI_MODULE_NAME("scan")
15 #define STRUCT_TO_INT(s)        (*((int*)&s))
16 extern struct acpi_device *acpi_root;
17
18 #define ACPI_BUS_CLASS                  "system_bus"
19 #define ACPI_BUS_HID                    "ACPI_BUS"
20 #define ACPI_BUS_DRIVER_NAME            "ACPI Bus Driver"
21 #define ACPI_BUS_DEVICE_NAME            "System Bus"
22
23 static LIST_HEAD(acpi_device_list);
24 DEFINE_SPINLOCK(acpi_device_lock);
25 LIST_HEAD(acpi_wakeup_device_list);
26
27
28 static void acpi_device_release(struct kobject *kobj)
29 {
30         struct acpi_device *dev = container_of(kobj, struct acpi_device, kobj);
31         kfree(dev->pnp.cid_list);
32         kfree(dev);
33 }
34
35 struct acpi_device_attribute {
36         struct attribute attr;
37          ssize_t(*show) (struct acpi_device *, char *);
38          ssize_t(*store) (struct acpi_device *, const char *, size_t);
39 };
40
41 typedef void acpi_device_sysfs_files(struct kobject *,
42                                      const struct attribute *);
43
44 static void setup_sys_fs_device_files(struct acpi_device *dev,
45                                       acpi_device_sysfs_files * func);
46
47 #define create_sysfs_device_files(dev)  \
48         setup_sys_fs_device_files(dev, (acpi_device_sysfs_files *)&sysfs_create_file)
49 #define remove_sysfs_device_files(dev)  \
50         setup_sys_fs_device_files(dev, (acpi_device_sysfs_files *)&sysfs_remove_file)
51
52 #define to_acpi_device(n) container_of(n, struct acpi_device, kobj)
53 #define to_handle_attr(n) container_of(n, struct acpi_device_attribute, attr);
54
55 static ssize_t acpi_device_attr_show(struct kobject *kobj,
56                                      struct attribute *attr, char *buf)
57 {
58         struct acpi_device *device = to_acpi_device(kobj);
59         struct acpi_device_attribute *attribute = to_handle_attr(attr);
60         return attribute->show ? attribute->show(device, buf) : -EIO;
61 }
62 static ssize_t acpi_device_attr_store(struct kobject *kobj,
63                                       struct attribute *attr, const char *buf,
64                                       size_t len)
65 {
66         struct acpi_device *device = to_acpi_device(kobj);
67         struct acpi_device_attribute *attribute = to_handle_attr(attr);
68         return attribute->store ? attribute->store(device, buf, len) : -EIO;
69 }
70
71 static struct sysfs_ops acpi_device_sysfs_ops = {
72         .show = acpi_device_attr_show,
73         .store = acpi_device_attr_store,
74 };
75
76 static struct kobj_type ktype_acpi_ns = {
77         .sysfs_ops = &acpi_device_sysfs_ops,
78         .release = acpi_device_release,
79 };
80
81 static int namespace_uevent(struct kset *kset, struct kobject *kobj,
82                              char **envp, int num_envp, char *buffer,
83                              int buffer_size)
84 {
85         struct acpi_device *dev = to_acpi_device(kobj);
86         int i = 0;
87         int len = 0;
88
89         if (!dev->driver)
90                 return 0;
91
92         if (add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
93                            "PHYSDEVDRIVER=%s", dev->driver->name))
94                 return -ENOMEM;
95
96         envp[i] = NULL;
97
98         return 0;
99 }
100
101 static struct kset_uevent_ops namespace_uevent_ops = {
102         .uevent = &namespace_uevent,
103 };
104
105 static struct kset acpi_namespace_kset = {
106         .kobj = {
107                  .name = "namespace",
108                  },
109         .subsys = &acpi_subsys,
110         .ktype = &ktype_acpi_ns,
111         .uevent_ops = &namespace_uevent_ops,
112 };
113
114 static void acpi_device_register(struct acpi_device *device,
115                                  struct acpi_device *parent)
116 {
117         int err;
118
119         /*
120          * Linkage
121          * -------
122          * Link this device to its parent and siblings.
123          */
124         INIT_LIST_HEAD(&device->children);
125         INIT_LIST_HEAD(&device->node);
126         INIT_LIST_HEAD(&device->g_list);
127         INIT_LIST_HEAD(&device->wakeup_list);
128
129         spin_lock(&acpi_device_lock);
130         if (device->parent) {
131                 list_add_tail(&device->node, &device->parent->children);
132                 list_add_tail(&device->g_list, &device->parent->g_list);
133         } else
134                 list_add_tail(&device->g_list, &acpi_device_list);
135         if (device->wakeup.flags.valid)
136                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
137         spin_unlock(&acpi_device_lock);
138
139         strlcpy(device->kobj.name, device->pnp.bus_id, KOBJ_NAME_LEN);
140         if (parent)
141                 device->kobj.parent = &parent->kobj;
142         device->kobj.ktype = &ktype_acpi_ns;
143         device->kobj.kset = &acpi_namespace_kset;
144         err = kobject_register(&device->kobj);
145         if (err < 0)
146                 printk(KERN_WARNING "%s: kobject_register error: %d\n",
147                         __FUNCTION__, err);
148         create_sysfs_device_files(device);
149 }
150
151 static void acpi_device_unregister(struct acpi_device *device, int type)
152 {
153         spin_lock(&acpi_device_lock);
154         if (device->parent) {
155                 list_del(&device->node);
156                 list_del(&device->g_list);
157         } else
158                 list_del(&device->g_list);
159
160         list_del(&device->wakeup_list);
161
162         spin_unlock(&acpi_device_lock);
163
164         acpi_detach_data(device->handle, acpi_bus_data_handler);
165         remove_sysfs_device_files(device);
166         kobject_unregister(&device->kobj);
167 }
168
169 void acpi_bus_data_handler(acpi_handle handle, u32 function, void *context)
170 {
171
172         /* TBD */
173
174         return;
175 }
176
177 static int acpi_bus_get_power_flags(struct acpi_device *device)
178 {
179         acpi_status status = 0;
180         acpi_handle handle = NULL;
181         u32 i = 0;
182
183
184         /*
185          * Power Management Flags
186          */
187         status = acpi_get_handle(device->handle, "_PSC", &handle);
188         if (ACPI_SUCCESS(status))
189                 device->power.flags.explicit_get = 1;
190         status = acpi_get_handle(device->handle, "_IRC", &handle);
191         if (ACPI_SUCCESS(status))
192                 device->power.flags.inrush_current = 1;
193
194         /*
195          * Enumerate supported power management states
196          */
197         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
198                 struct acpi_device_power_state *ps = &device->power.states[i];
199                 char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
200
201                 /* Evaluate "_PRx" to se if power resources are referenced */
202                 acpi_evaluate_reference(device->handle, object_name, NULL,
203                                         &ps->resources);
204                 if (ps->resources.count) {
205                         device->power.flags.power_resources = 1;
206                         ps->flags.valid = 1;
207                 }
208
209                 /* Evaluate "_PSx" to see if we can do explicit sets */
210                 object_name[2] = 'S';
211                 status = acpi_get_handle(device->handle, object_name, &handle);
212                 if (ACPI_SUCCESS(status)) {
213                         ps->flags.explicit_set = 1;
214                         ps->flags.valid = 1;
215                 }
216
217                 /* State is valid if we have some power control */
218                 if (ps->resources.count || ps->flags.explicit_set)
219                         ps->flags.valid = 1;
220
221                 ps->power = -1; /* Unknown - driver assigned */
222                 ps->latency = -1;       /* Unknown - driver assigned */
223         }
224
225         /* Set defaults for D0 and D3 states (always valid) */
226         device->power.states[ACPI_STATE_D0].flags.valid = 1;
227         device->power.states[ACPI_STATE_D0].power = 100;
228         device->power.states[ACPI_STATE_D3].flags.valid = 1;
229         device->power.states[ACPI_STATE_D3].power = 0;
230
231         /* TBD: System wake support and resource requirements. */
232
233         device->power.state = ACPI_STATE_UNKNOWN;
234
235         return 0;
236 }
237
238 int acpi_match_ids(struct acpi_device *device, char *ids)
239 {
240         if (device->flags.hardware_id)
241                 if (strstr(ids, device->pnp.hardware_id))
242                         return 0;
243
244         if (device->flags.compatible_ids) {
245                 struct acpi_compatible_id_list *cid_list = device->pnp.cid_list;
246                 int i;
247
248                 /* compare multiple _CID entries against driver ids */
249                 for (i = 0; i < cid_list->count; i++) {
250                         if (strstr(ids, cid_list->id[i].value))
251                                 return 0;
252                 }
253         }
254         return -ENOENT;
255 }
256
257 static acpi_status
258 acpi_bus_extract_wakeup_device_power_package(struct acpi_device *device,
259                                              union acpi_object *package)
260 {
261         int i = 0;
262         union acpi_object *element = NULL;
263
264         if (!device || !package || (package->package.count < 2))
265                 return AE_BAD_PARAMETER;
266
267         element = &(package->package.elements[0]);
268         if (!element)
269                 return AE_BAD_PARAMETER;
270         if (element->type == ACPI_TYPE_PACKAGE) {
271                 if ((element->package.count < 2) ||
272                     (element->package.elements[0].type !=
273                      ACPI_TYPE_LOCAL_REFERENCE)
274                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
275                         return AE_BAD_DATA;
276                 device->wakeup.gpe_device =
277                     element->package.elements[0].reference.handle;
278                 device->wakeup.gpe_number =
279                     (u32) element->package.elements[1].integer.value;
280         } else if (element->type == ACPI_TYPE_INTEGER) {
281                 device->wakeup.gpe_number = element->integer.value;
282         } else
283                 return AE_BAD_DATA;
284
285         element = &(package->package.elements[1]);
286         if (element->type != ACPI_TYPE_INTEGER) {
287                 return AE_BAD_DATA;
288         }
289         device->wakeup.sleep_state = element->integer.value;
290
291         if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
292                 return AE_NO_MEMORY;
293         }
294         device->wakeup.resources.count = package->package.count - 2;
295         for (i = 0; i < device->wakeup.resources.count; i++) {
296                 element = &(package->package.elements[i + 2]);
297                 if (element->type != ACPI_TYPE_ANY) {
298                         return AE_BAD_DATA;
299                 }
300
301                 device->wakeup.resources.handles[i] = element->reference.handle;
302         }
303
304         return AE_OK;
305 }
306
307 static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
308 {
309         acpi_status status = 0;
310         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
311         union acpi_object *package = NULL;
312
313
314         /* _PRW */
315         status = acpi_evaluate_object(device->handle, "_PRW", NULL, &buffer);
316         if (ACPI_FAILURE(status)) {
317                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
318                 goto end;
319         }
320
321         package = (union acpi_object *)buffer.pointer;
322         status = acpi_bus_extract_wakeup_device_power_package(device, package);
323         if (ACPI_FAILURE(status)) {
324                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _PRW package"));
325                 goto end;
326         }
327
328         kfree(buffer.pointer);
329
330         device->wakeup.flags.valid = 1;
331         /* Power button, Lid switch always enable wakeup */
332         if (!acpi_match_ids(device, "PNP0C0D,PNP0C0C,PNP0C0E"))
333                 device->wakeup.flags.run_wake = 1;
334
335       end:
336         if (ACPI_FAILURE(status))
337                 device->flags.wake_capable = 0;
338         return 0;
339 }
340
341 /* --------------------------------------------------------------------------
342                 ACPI sysfs device file support
343    -------------------------------------------------------------------------- */
344 static ssize_t acpi_eject_store(struct acpi_device *device,
345                                 const char *buf, size_t count);
346
347 #define ACPI_DEVICE_ATTR(_name,_mode,_show,_store) \
348 static struct acpi_device_attribute acpi_device_attr_##_name = \
349                 __ATTR(_name, _mode, _show, _store)
350
351 ACPI_DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
352
353 /**
354  * setup_sys_fs_device_files - sets up the device files under device namespace
355  * @dev:        acpi_device object
356  * @func:       function pointer to create or destroy the device file
357  */
358 static void
359 setup_sys_fs_device_files(struct acpi_device *dev,
360                           acpi_device_sysfs_files * func)
361 {
362         acpi_status status;
363         acpi_handle temp = NULL;
364
365         /*
366          * If device has _EJ0, 'eject' file is created that is used to trigger
367          * hot-removal function from userland.
368          */
369         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
370         if (ACPI_SUCCESS(status))
371                 (*(func)) (&dev->kobj, &acpi_device_attr_eject.attr);
372 }
373
374 static int acpi_eject_operation(acpi_handle handle, int lockable)
375 {
376         struct acpi_object_list arg_list;
377         union acpi_object arg;
378         acpi_status status = AE_OK;
379
380         /*
381          * TBD: evaluate _PS3?
382          */
383
384         if (lockable) {
385                 arg_list.count = 1;
386                 arg_list.pointer = &arg;
387                 arg.type = ACPI_TYPE_INTEGER;
388                 arg.integer.value = 0;
389                 acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
390         }
391
392         arg_list.count = 1;
393         arg_list.pointer = &arg;
394         arg.type = ACPI_TYPE_INTEGER;
395         arg.integer.value = 1;
396
397         /*
398          * TBD: _EJD support.
399          */
400
401         status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
402         if (ACPI_FAILURE(status)) {
403                 return (-ENODEV);
404         }
405
406         return (0);
407 }
408
409 static ssize_t
410 acpi_eject_store(struct acpi_device *device, const char *buf, size_t count)
411 {
412         int result;
413         int ret = count;
414         int islockable;
415         acpi_status status;
416         acpi_handle handle;
417         acpi_object_type type = 0;
418
419         if ((!count) || (buf[0] != '1')) {
420                 return -EINVAL;
421         }
422 #ifndef FORCE_EJECT
423         if (device->driver == NULL) {
424                 ret = -ENODEV;
425                 goto err;
426         }
427 #endif
428         status = acpi_get_type(device->handle, &type);
429         if (ACPI_FAILURE(status) || (!device->flags.ejectable)) {
430                 ret = -ENODEV;
431                 goto err;
432         }
433
434         islockable = device->flags.lockable;
435         handle = device->handle;
436
437         result = acpi_bus_trim(device, 1);
438
439         if (!result)
440                 result = acpi_eject_operation(handle, islockable);
441
442         if (result) {
443                 ret = -EBUSY;
444         }
445       err:
446         return ret;
447 }
448
449 /* --------------------------------------------------------------------------
450                               Performance Management
451    -------------------------------------------------------------------------- */
452
453 static int acpi_bus_get_perf_flags(struct acpi_device *device)
454 {
455         device->performance.state = ACPI_STATE_UNKNOWN;
456         return 0;
457 }
458
459 /* --------------------------------------------------------------------------
460                                  Driver Management
461    -------------------------------------------------------------------------- */
462
463 static LIST_HEAD(acpi_bus_drivers);
464
465 /**
466  * acpi_bus_match - match device IDs to driver's supported IDs
467  * @device: the device that we are trying to match to a driver
468  * @driver: driver whose device id table is being checked
469  *
470  * Checks the device's hardware (_HID) or compatible (_CID) ids to see if it
471  * matches the specified driver's criteria.
472  */
473 static int
474 acpi_bus_match(struct acpi_device *device, struct acpi_driver *driver)
475 {
476         if (driver && driver->ops.match)
477                 return driver->ops.match(device, driver);
478         return acpi_match_ids(device, driver->ids);
479 }
480
481 /**
482  * acpi_bus_driver_init - add a device to a driver
483  * @device: the device to add and initialize
484  * @driver: driver for the device
485  *
486  * Used to initialize a device via its device driver.  Called whenever a 
487  * driver is bound to a device.  Invokes the driver's add() and start() ops.
488  */
489 static int
490 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
491 {
492         int result = 0;
493
494
495         if (!device || !driver)
496                 return -EINVAL;
497
498         if (!driver->ops.add)
499                 return -ENOSYS;
500
501         result = driver->ops.add(device);
502         if (result) {
503                 device->driver = NULL;
504                 acpi_driver_data(device) = NULL;
505                 return result;
506         }
507
508         device->driver = driver;
509
510         /*
511          * TBD - Configuration Management: Assign resources to device based
512          * upon possible configuration and currently allocated resources.
513          */
514
515         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
516                           "Driver successfully bound to device\n"));
517         return 0;
518 }
519
520 static int acpi_start_single_object(struct acpi_device *device)
521 {
522         int result = 0;
523         struct acpi_driver *driver;
524
525
526         if (!(driver = device->driver))
527                 return 0;
528
529         if (driver->ops.start) {
530                 result = driver->ops.start(device);
531                 if (result && driver->ops.remove)
532                         driver->ops.remove(device, ACPI_BUS_REMOVAL_NORMAL);
533         }
534
535         return result;
536 }
537
538 static void acpi_driver_attach(struct acpi_driver *drv)
539 {
540         struct list_head *node, *next;
541
542
543         spin_lock(&acpi_device_lock);
544         list_for_each_safe(node, next, &acpi_device_list) {
545                 struct acpi_device *dev =
546                     container_of(node, struct acpi_device, g_list);
547
548                 if (dev->driver || !dev->status.present)
549                         continue;
550                 spin_unlock(&acpi_device_lock);
551
552                 if (!acpi_bus_match(dev, drv)) {
553                         if (!acpi_bus_driver_init(dev, drv)) {
554                                 acpi_start_single_object(dev);
555                                 atomic_inc(&drv->references);
556                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
557                                                   "Found driver [%s] for device [%s]\n",
558                                                   drv->name, dev->pnp.bus_id));
559                         }
560                 }
561                 spin_lock(&acpi_device_lock);
562         }
563         spin_unlock(&acpi_device_lock);
564 }
565
566 static void acpi_driver_detach(struct acpi_driver *drv)
567 {
568         struct list_head *node, *next;
569
570
571         spin_lock(&acpi_device_lock);
572         list_for_each_safe(node, next, &acpi_device_list) {
573                 struct acpi_device *dev =
574                     container_of(node, struct acpi_device, g_list);
575
576                 if (dev->driver == drv) {
577                         spin_unlock(&acpi_device_lock);
578                         if (drv->ops.remove)
579                                 drv->ops.remove(dev, ACPI_BUS_REMOVAL_NORMAL);
580                         spin_lock(&acpi_device_lock);
581                         dev->driver = NULL;
582                         dev->driver_data = NULL;
583                         atomic_dec(&drv->references);
584                 }
585         }
586         spin_unlock(&acpi_device_lock);
587 }
588
589 /**
590  * acpi_bus_register_driver - register a driver with the ACPI bus
591  * @driver: driver being registered
592  *
593  * Registers a driver with the ACPI bus.  Searches the namespace for all
594  * devices that match the driver's criteria and binds.  Returns zero for
595  * success or a negative error status for failure.
596  */
597 int acpi_bus_register_driver(struct acpi_driver *driver)
598 {
599
600         if (acpi_disabled)
601                 return -ENODEV;
602
603         spin_lock(&acpi_device_lock);
604         list_add_tail(&driver->node, &acpi_bus_drivers);
605         spin_unlock(&acpi_device_lock);
606         acpi_driver_attach(driver);
607
608         return 0;
609 }
610
611 EXPORT_SYMBOL(acpi_bus_register_driver);
612
613 /**
614  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
615  * @driver: driver to unregister
616  *
617  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
618  * devices that match the driver's criteria and unbinds.
619  */
620 void acpi_bus_unregister_driver(struct acpi_driver *driver)
621 {
622         acpi_driver_detach(driver);
623
624         if (!atomic_read(&driver->references)) {
625                 spin_lock(&acpi_device_lock);
626                 list_del_init(&driver->node);
627                 spin_unlock(&acpi_device_lock);
628         }
629         return;
630 }
631
632 EXPORT_SYMBOL(acpi_bus_unregister_driver);
633
634 /**
635  * acpi_bus_find_driver - check if there is a driver installed for the device
636  * @device: device that we are trying to find a supporting driver for
637  *
638  * Parses the list of registered drivers looking for a driver applicable for
639  * the specified device.
640  */
641 static int acpi_bus_find_driver(struct acpi_device *device)
642 {
643         int result = 0;
644         struct list_head *node, *next;
645
646
647         spin_lock(&acpi_device_lock);
648         list_for_each_safe(node, next, &acpi_bus_drivers) {
649                 struct acpi_driver *driver =
650                     container_of(node, struct acpi_driver, node);
651
652                 atomic_inc(&driver->references);
653                 spin_unlock(&acpi_device_lock);
654                 if (!acpi_bus_match(device, driver)) {
655                         result = acpi_bus_driver_init(device, driver);
656                         if (!result)
657                                 goto Done;
658                 }
659                 atomic_dec(&driver->references);
660                 spin_lock(&acpi_device_lock);
661         }
662         spin_unlock(&acpi_device_lock);
663
664       Done:
665         return result;
666 }
667
668 /* --------------------------------------------------------------------------
669                                  Device Enumeration
670    -------------------------------------------------------------------------- */
671
672 acpi_status
673 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
674 {
675         acpi_status status;
676         acpi_handle tmp;
677         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
678         union acpi_object *obj;
679
680         status = acpi_get_handle(handle, "_EJD", &tmp);
681         if (ACPI_FAILURE(status))
682                 return status;
683
684         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
685         if (ACPI_SUCCESS(status)) {
686                 obj = buffer.pointer;
687                 status = acpi_get_handle(NULL, obj->string.pointer, ejd);
688                 kfree(buffer.pointer);
689         }
690         return status;
691 }
692 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
693
694
695 static int acpi_bus_get_flags(struct acpi_device *device)
696 {
697         acpi_status status = AE_OK;
698         acpi_handle temp = NULL;
699
700
701         /* Presence of _STA indicates 'dynamic_status' */
702         status = acpi_get_handle(device->handle, "_STA", &temp);
703         if (ACPI_SUCCESS(status))
704                 device->flags.dynamic_status = 1;
705
706         /* Presence of _CID indicates 'compatible_ids' */
707         status = acpi_get_handle(device->handle, "_CID", &temp);
708         if (ACPI_SUCCESS(status))
709                 device->flags.compatible_ids = 1;
710
711         /* Presence of _RMV indicates 'removable' */
712         status = acpi_get_handle(device->handle, "_RMV", &temp);
713         if (ACPI_SUCCESS(status))
714                 device->flags.removable = 1;
715
716         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
717         status = acpi_get_handle(device->handle, "_EJD", &temp);
718         if (ACPI_SUCCESS(status))
719                 device->flags.ejectable = 1;
720         else {
721                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
722                 if (ACPI_SUCCESS(status))
723                         device->flags.ejectable = 1;
724         }
725
726         /* Presence of _LCK indicates 'lockable' */
727         status = acpi_get_handle(device->handle, "_LCK", &temp);
728         if (ACPI_SUCCESS(status))
729                 device->flags.lockable = 1;
730
731         /* Presence of _PS0|_PR0 indicates 'power manageable' */
732         status = acpi_get_handle(device->handle, "_PS0", &temp);
733         if (ACPI_FAILURE(status))
734                 status = acpi_get_handle(device->handle, "_PR0", &temp);
735         if (ACPI_SUCCESS(status))
736                 device->flags.power_manageable = 1;
737
738         /* Presence of _PRW indicates wake capable */
739         status = acpi_get_handle(device->handle, "_PRW", &temp);
740         if (ACPI_SUCCESS(status))
741                 device->flags.wake_capable = 1;
742
743         /* TBD: Peformance management */
744
745         return 0;
746 }
747
748 static void acpi_device_get_busid(struct acpi_device *device,
749                                   acpi_handle handle, int type)
750 {
751         char bus_id[5] = { '?', 0 };
752         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
753         int i = 0;
754
755         /*
756          * Bus ID
757          * ------
758          * The device's Bus ID is simply the object name.
759          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
760          */
761         switch (type) {
762         case ACPI_BUS_TYPE_SYSTEM:
763                 strcpy(device->pnp.bus_id, "ACPI");
764                 break;
765         case ACPI_BUS_TYPE_POWER_BUTTON:
766                 strcpy(device->pnp.bus_id, "PWRF");
767                 break;
768         case ACPI_BUS_TYPE_SLEEP_BUTTON:
769                 strcpy(device->pnp.bus_id, "SLPF");
770                 break;
771         default:
772                 acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
773                 /* Clean up trailing underscores (if any) */
774                 for (i = 3; i > 1; i--) {
775                         if (bus_id[i] == '_')
776                                 bus_id[i] = '\0';
777                         else
778                                 break;
779                 }
780                 strcpy(device->pnp.bus_id, bus_id);
781                 break;
782         }
783 }
784
785 static void acpi_device_set_id(struct acpi_device *device,
786                                struct acpi_device *parent, acpi_handle handle,
787                                int type)
788 {
789         struct acpi_device_info *info;
790         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
791         char *hid = NULL;
792         char *uid = NULL;
793         struct acpi_compatible_id_list *cid_list = NULL;
794         acpi_status status;
795
796         switch (type) {
797         case ACPI_BUS_TYPE_DEVICE:
798                 status = acpi_get_object_info(handle, &buffer);
799                 if (ACPI_FAILURE(status)) {
800                         printk("%s: Error reading device info\n", __FUNCTION__);
801                         return;
802                 }
803
804                 info = buffer.pointer;
805                 if (info->valid & ACPI_VALID_HID)
806                         hid = info->hardware_id.value;
807                 if (info->valid & ACPI_VALID_UID)
808                         uid = info->unique_id.value;
809                 if (info->valid & ACPI_VALID_CID)
810                         cid_list = &info->compatibility_id;
811                 if (info->valid & ACPI_VALID_ADR) {
812                         device->pnp.bus_address = info->address;
813                         device->flags.bus_address = 1;
814                 }
815                 break;
816         case ACPI_BUS_TYPE_POWER:
817                 hid = ACPI_POWER_HID;
818                 break;
819         case ACPI_BUS_TYPE_PROCESSOR:
820                 hid = ACPI_PROCESSOR_HID;
821                 break;
822         case ACPI_BUS_TYPE_SYSTEM:
823                 hid = ACPI_SYSTEM_HID;
824                 break;
825         case ACPI_BUS_TYPE_THERMAL:
826                 hid = ACPI_THERMAL_HID;
827                 break;
828         case ACPI_BUS_TYPE_POWER_BUTTON:
829                 hid = ACPI_BUTTON_HID_POWERF;
830                 break;
831         case ACPI_BUS_TYPE_SLEEP_BUTTON:
832                 hid = ACPI_BUTTON_HID_SLEEPF;
833                 break;
834         }
835
836         /* 
837          * \_SB
838          * ----
839          * Fix for the system root bus device -- the only root-level device.
840          */
841         if (((acpi_handle)parent == ACPI_ROOT_OBJECT) && (type == ACPI_BUS_TYPE_DEVICE)) {
842                 hid = ACPI_BUS_HID;
843                 strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
844                 strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
845         }
846
847         if (hid) {
848                 strcpy(device->pnp.hardware_id, hid);
849                 device->flags.hardware_id = 1;
850         }
851         if (uid) {
852                 strcpy(device->pnp.unique_id, uid);
853                 device->flags.unique_id = 1;
854         }
855         if (cid_list) {
856                 device->pnp.cid_list = kmalloc(cid_list->size, GFP_KERNEL);
857                 if (device->pnp.cid_list)
858                         memcpy(device->pnp.cid_list, cid_list, cid_list->size);
859                 else
860                         printk(KERN_ERR "Memory allocation error\n");
861         }
862
863         kfree(buffer.pointer);
864 }
865
866 static int acpi_device_set_context(struct acpi_device *device, int type)
867 {
868         acpi_status status = AE_OK;
869         int result = 0;
870         /*
871          * Context
872          * -------
873          * Attach this 'struct acpi_device' to the ACPI object.  This makes
874          * resolutions from handle->device very efficient.  Note that we need
875          * to be careful with fixed-feature devices as they all attach to the
876          * root object.
877          */
878         if (type != ACPI_BUS_TYPE_POWER_BUTTON &&
879             type != ACPI_BUS_TYPE_SLEEP_BUTTON) {
880                 status = acpi_attach_data(device->handle,
881                                           acpi_bus_data_handler, device);
882
883                 if (ACPI_FAILURE(status)) {
884                         printk("Error attaching device data\n");
885                         result = -ENODEV;
886                 }
887         }
888         return result;
889 }
890
891 static void acpi_device_get_debug_info(struct acpi_device *device,
892                                        acpi_handle handle, int type)
893 {
894 #ifdef CONFIG_ACPI_DEBUG_OUTPUT
895         char *type_string = NULL;
896         char name[80] = { '?', '\0' };
897         struct acpi_buffer buffer = { sizeof(name), name };
898
899         switch (type) {
900         case ACPI_BUS_TYPE_DEVICE:
901                 type_string = "Device";
902                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
903                 break;
904         case ACPI_BUS_TYPE_POWER:
905                 type_string = "Power Resource";
906                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
907                 break;
908         case ACPI_BUS_TYPE_PROCESSOR:
909                 type_string = "Processor";
910                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
911                 break;
912         case ACPI_BUS_TYPE_SYSTEM:
913                 type_string = "System";
914                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
915                 break;
916         case ACPI_BUS_TYPE_THERMAL:
917                 type_string = "Thermal Zone";
918                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
919                 break;
920         case ACPI_BUS_TYPE_POWER_BUTTON:
921                 type_string = "Power Button";
922                 sprintf(name, "PWRB");
923                 break;
924         case ACPI_BUS_TYPE_SLEEP_BUTTON:
925                 type_string = "Sleep Button";
926                 sprintf(name, "SLPB");
927                 break;
928         }
929
930         printk(KERN_DEBUG "Found %s %s [%p]\n", type_string, name, handle);
931 #endif                          /*CONFIG_ACPI_DEBUG_OUTPUT */
932 }
933
934 static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
935 {
936         int result = 0;
937         struct acpi_driver *driver;
938
939
940         if (!dev)
941                 return -EINVAL;
942
943         driver = dev->driver;
944
945         if ((driver) && (driver->ops.remove)) {
946
947                 if (driver->ops.stop) {
948                         result = driver->ops.stop(dev, ACPI_BUS_REMOVAL_EJECT);
949                         if (result)
950                                 return result;
951                 }
952
953                 result = dev->driver->ops.remove(dev, ACPI_BUS_REMOVAL_EJECT);
954                 if (result) {
955                         return result;
956                 }
957
958                 atomic_dec(&dev->driver->references);
959                 dev->driver = NULL;
960                 acpi_driver_data(dev) = NULL;
961         }
962
963         if (!rmdevice)
964                 return 0;
965
966         if (dev->flags.bus_address) {
967                 if ((dev->parent) && (dev->parent->ops.unbind))
968                         dev->parent->ops.unbind(dev);
969         }
970
971         acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
972
973         return 0;
974 }
975
976 static int
977 acpi_add_single_object(struct acpi_device **child,
978                        struct acpi_device *parent, acpi_handle handle, int type)
979 {
980         int result = 0;
981         struct acpi_device *device = NULL;
982
983
984         if (!child)
985                 return -EINVAL;
986
987         device = kmalloc(sizeof(struct acpi_device), GFP_KERNEL);
988         if (!device) {
989                 printk(KERN_ERR PREFIX "Memory allocation error\n");
990                 return -ENOMEM;
991         }
992         memset(device, 0, sizeof(struct acpi_device));
993
994         device->handle = handle;
995         device->parent = parent;
996
997         acpi_device_get_busid(device, handle, type);
998
999         /*
1000          * Flags
1001          * -----
1002          * Get prior to calling acpi_bus_get_status() so we know whether
1003          * or not _STA is present.  Note that we only look for object
1004          * handles -- cannot evaluate objects until we know the device is
1005          * present and properly initialized.
1006          */
1007         result = acpi_bus_get_flags(device);
1008         if (result)
1009                 goto end;
1010
1011         /*
1012          * Status
1013          * ------
1014          * See if the device is present.  We always assume that non-Device
1015          * and non-Processor objects (e.g. thermal zones, power resources,
1016          * etc.) are present, functioning, etc. (at least when parent object
1017          * is present).  Note that _STA has a different meaning for some
1018          * objects (e.g. power resources) so we need to be careful how we use
1019          * it.
1020          */
1021         switch (type) {
1022         case ACPI_BUS_TYPE_PROCESSOR:
1023         case ACPI_BUS_TYPE_DEVICE:
1024                 result = acpi_bus_get_status(device);
1025                 if (ACPI_FAILURE(result) || !device->status.present) {
1026                         result = -ENOENT;
1027                         goto end;
1028                 }
1029                 break;
1030         default:
1031                 STRUCT_TO_INT(device->status) = 0x0F;
1032                 break;
1033         }
1034
1035         /*
1036          * Initialize Device
1037          * -----------------
1038          * TBD: Synch with Core's enumeration/initialization process.
1039          */
1040
1041         /*
1042          * Hardware ID, Unique ID, & Bus Address
1043          * -------------------------------------
1044          */
1045         acpi_device_set_id(device, parent, handle, type);
1046
1047         /*
1048          * Power Management
1049          * ----------------
1050          */
1051         if (device->flags.power_manageable) {
1052                 result = acpi_bus_get_power_flags(device);
1053                 if (result)
1054                         goto end;
1055         }
1056
1057         /*
1058          * Wakeup device management
1059          *-----------------------
1060          */
1061         if (device->flags.wake_capable) {
1062                 result = acpi_bus_get_wakeup_device_flags(device);
1063                 if (result)
1064                         goto end;
1065         }
1066
1067         /*
1068          * Performance Management
1069          * ----------------------
1070          */
1071         if (device->flags.performance_manageable) {
1072                 result = acpi_bus_get_perf_flags(device);
1073                 if (result)
1074                         goto end;
1075         }
1076
1077         if ((result = acpi_device_set_context(device, type)))
1078                 goto end;
1079
1080         acpi_device_get_debug_info(device, handle, type);
1081
1082         acpi_device_register(device, parent);
1083
1084         /*
1085          * Bind _ADR-Based Devices
1086          * -----------------------
1087          * If there's a a bus address (_ADR) then we utilize the parent's 
1088          * 'bind' function (if exists) to bind the ACPI- and natively-
1089          * enumerated device representations.
1090          */
1091         if (device->flags.bus_address) {
1092                 if (device->parent && device->parent->ops.bind)
1093                         device->parent->ops.bind(device);
1094         }
1095
1096         /*
1097          * Locate & Attach Driver
1098          * ----------------------
1099          * If there's a hardware id (_HID) or compatible ids (_CID) we check
1100          * to see if there's a driver installed for this kind of device.  Note
1101          * that drivers can install before or after a device is enumerated.
1102          *
1103          * TBD: Assumes LDM provides driver hot-plug capability.
1104          */
1105         acpi_bus_find_driver(device);
1106
1107       end:
1108         if (!result)
1109                 *child = device;
1110         else {
1111                 kfree(device->pnp.cid_list);
1112                 kfree(device);
1113         }
1114
1115         return result;
1116 }
1117
1118 static int acpi_bus_scan(struct acpi_device *start, struct acpi_bus_ops *ops)
1119 {
1120         acpi_status status = AE_OK;
1121         struct acpi_device *parent = NULL;
1122         struct acpi_device *child = NULL;
1123         acpi_handle phandle = NULL;
1124         acpi_handle chandle = NULL;
1125         acpi_object_type type = 0;
1126         u32 level = 1;
1127
1128
1129         if (!start)
1130                 return -EINVAL;
1131
1132         parent = start;
1133         phandle = start->handle;
1134
1135         /*
1136          * Parse through the ACPI namespace, identify all 'devices', and
1137          * create a new 'struct acpi_device' for each.
1138          */
1139         while ((level > 0) && parent) {
1140
1141                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1142                                               chandle, &chandle);
1143
1144                 /*
1145                  * If this scope is exhausted then move our way back up.
1146                  */
1147                 if (ACPI_FAILURE(status)) {
1148                         level--;
1149                         chandle = phandle;
1150                         acpi_get_parent(phandle, &phandle);
1151                         if (parent->parent)
1152                                 parent = parent->parent;
1153                         continue;
1154                 }
1155
1156                 status = acpi_get_type(chandle, &type);
1157                 if (ACPI_FAILURE(status))
1158                         continue;
1159
1160                 /*
1161                  * If this is a scope object then parse it (depth-first).
1162                  */
1163                 if (type == ACPI_TYPE_LOCAL_SCOPE) {
1164                         level++;
1165                         phandle = chandle;
1166                         chandle = NULL;
1167                         continue;
1168                 }
1169
1170                 /*
1171                  * We're only interested in objects that we consider 'devices'.
1172                  */
1173                 switch (type) {
1174                 case ACPI_TYPE_DEVICE:
1175                         type = ACPI_BUS_TYPE_DEVICE;
1176                         break;
1177                 case ACPI_TYPE_PROCESSOR:
1178                         type = ACPI_BUS_TYPE_PROCESSOR;
1179                         break;
1180                 case ACPI_TYPE_THERMAL:
1181                         type = ACPI_BUS_TYPE_THERMAL;
1182                         break;
1183                 case ACPI_TYPE_POWER:
1184                         type = ACPI_BUS_TYPE_POWER;
1185                         break;
1186                 default:
1187                         continue;
1188                 }
1189
1190                 if (ops->acpi_op_add)
1191                         status = acpi_add_single_object(&child, parent,
1192                                                         chandle, type);
1193                 else
1194                         status = acpi_bus_get_device(chandle, &child);
1195
1196                 if (ACPI_FAILURE(status))
1197                         continue;
1198
1199                 if (ops->acpi_op_start) {
1200                         status = acpi_start_single_object(child);
1201                         if (ACPI_FAILURE(status))
1202                                 continue;
1203                 }
1204
1205                 /*
1206                  * If the device is present, enabled, and functioning then
1207                  * parse its scope (depth-first).  Note that we need to
1208                  * represent absent devices to facilitate PnP notifications
1209                  * -- but only the subtree head (not all of its children,
1210                  * which will be enumerated when the parent is inserted).
1211                  *
1212                  * TBD: Need notifications and other detection mechanisms
1213                  *      in place before we can fully implement this.
1214                  */
1215                 if (child->status.present) {
1216                         status = acpi_get_next_object(ACPI_TYPE_ANY, chandle,
1217                                                       NULL, NULL);
1218                         if (ACPI_SUCCESS(status)) {
1219                                 level++;
1220                                 phandle = chandle;
1221                                 chandle = NULL;
1222                                 parent = child;
1223                         }
1224                 }
1225         }
1226
1227         return 0;
1228 }
1229
1230 int
1231 acpi_bus_add(struct acpi_device **child,
1232              struct acpi_device *parent, acpi_handle handle, int type)
1233 {
1234         int result;
1235         struct acpi_bus_ops ops;
1236
1237
1238         result = acpi_add_single_object(child, parent, handle, type);
1239         if (!result) {
1240                 memset(&ops, 0, sizeof(ops));
1241                 ops.acpi_op_add = 1;
1242                 result = acpi_bus_scan(*child, &ops);
1243         }
1244         return result;
1245 }
1246
1247 EXPORT_SYMBOL(acpi_bus_add);
1248
1249 int acpi_bus_start(struct acpi_device *device)
1250 {
1251         int result;
1252         struct acpi_bus_ops ops;
1253
1254
1255         if (!device)
1256                 return -EINVAL;
1257
1258         result = acpi_start_single_object(device);
1259         if (!result) {
1260                 memset(&ops, 0, sizeof(ops));
1261                 ops.acpi_op_start = 1;
1262                 result = acpi_bus_scan(device, &ops);
1263         }
1264         return result;
1265 }
1266
1267 EXPORT_SYMBOL(acpi_bus_start);
1268
1269 int acpi_bus_trim(struct acpi_device *start, int rmdevice)
1270 {
1271         acpi_status status;
1272         struct acpi_device *parent, *child;
1273         acpi_handle phandle, chandle;
1274         acpi_object_type type;
1275         u32 level = 1;
1276         int err = 0;
1277
1278         parent = start;
1279         phandle = start->handle;
1280         child = chandle = NULL;
1281
1282         while ((level > 0) && parent && (!err)) {
1283                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1284                                               chandle, &chandle);
1285
1286                 /*
1287                  * If this scope is exhausted then move our way back up.
1288                  */
1289                 if (ACPI_FAILURE(status)) {
1290                         level--;
1291                         chandle = phandle;
1292                         acpi_get_parent(phandle, &phandle);
1293                         child = parent;
1294                         parent = parent->parent;
1295
1296                         if (level == 0)
1297                                 err = acpi_bus_remove(child, rmdevice);
1298                         else
1299                                 err = acpi_bus_remove(child, 1);
1300
1301                         continue;
1302                 }
1303
1304                 status = acpi_get_type(chandle, &type);
1305                 if (ACPI_FAILURE(status)) {
1306                         continue;
1307                 }
1308                 /*
1309                  * If there is a device corresponding to chandle then
1310                  * parse it (depth-first).
1311                  */
1312                 if (acpi_bus_get_device(chandle, &child) == 0) {
1313                         level++;
1314                         phandle = chandle;
1315                         chandle = NULL;
1316                         parent = child;
1317                 }
1318                 continue;
1319         }
1320         return err;
1321 }
1322 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1323
1324
1325 static int acpi_bus_scan_fixed(struct acpi_device *root)
1326 {
1327         int result = 0;
1328         struct acpi_device *device = NULL;
1329
1330
1331         if (!root)
1332                 return -ENODEV;
1333
1334         /*
1335          * Enumerate all fixed-feature devices.
1336          */
1337         if (acpi_fadt.pwr_button == 0) {
1338                 result = acpi_add_single_object(&device, acpi_root,
1339                                                 NULL,
1340                                                 ACPI_BUS_TYPE_POWER_BUTTON);
1341                 if (!result)
1342                         result = acpi_start_single_object(device);
1343         }
1344
1345         if (acpi_fadt.sleep_button == 0) {
1346                 result = acpi_add_single_object(&device, acpi_root,
1347                                                 NULL,
1348                                                 ACPI_BUS_TYPE_SLEEP_BUTTON);
1349                 if (!result)
1350                         result = acpi_start_single_object(device);
1351         }
1352
1353         return result;
1354 }
1355
1356
1357 static inline struct acpi_device * to_acpi_dev(struct device * dev)
1358 {
1359         return container_of(dev, struct acpi_device, dev);
1360 }
1361
1362
1363 static int root_suspend(struct acpi_device * acpi_dev, pm_message_t state)
1364 {
1365         struct acpi_device * dev, * next;
1366         int result;
1367
1368         spin_lock(&acpi_device_lock);
1369         list_for_each_entry_safe_reverse(dev, next, &acpi_device_list, g_list) {
1370                 if (dev->driver && dev->driver->ops.suspend) {
1371                         spin_unlock(&acpi_device_lock);
1372                         result = dev->driver->ops.suspend(dev, 0);
1373                         if (result) {
1374                                 printk(KERN_ERR PREFIX "[%s - %s] Suspend failed: %d\n",
1375                                        acpi_device_name(dev),
1376                                        acpi_device_bid(dev), result);
1377                         }
1378                         spin_lock(&acpi_device_lock);
1379                 }
1380         }
1381         spin_unlock(&acpi_device_lock);
1382         return 0;
1383 }
1384
1385
1386 static int acpi_device_suspend(struct device * dev, pm_message_t state)
1387 {
1388         struct acpi_device * acpi_dev = to_acpi_dev(dev);
1389
1390         /*
1391          * For now, we should only register 1 generic device -
1392          * the ACPI root device - and from there, we walk the
1393          * tree of ACPI devices to suspend each one using the
1394          * ACPI driver methods.
1395          */
1396         if (acpi_dev->handle == ACPI_ROOT_OBJECT)
1397                 root_suspend(acpi_dev, state);
1398         return 0;
1399 }
1400
1401
1402
1403 static int root_resume(struct acpi_device * acpi_dev)
1404 {
1405         struct acpi_device * dev, * next;
1406         int result;
1407
1408         spin_lock(&acpi_device_lock);
1409         list_for_each_entry_safe(dev, next, &acpi_device_list, g_list) {
1410                 if (dev->driver && dev->driver->ops.resume) {
1411                         spin_unlock(&acpi_device_lock);
1412                         result = dev->driver->ops.resume(dev, 0);
1413                         if (result) {
1414                                 printk(KERN_ERR PREFIX "[%s - %s] resume failed: %d\n",
1415                                        acpi_device_name(dev),
1416                                        acpi_device_bid(dev), result);
1417                         }
1418                         spin_lock(&acpi_device_lock);
1419                 }
1420         }
1421         spin_unlock(&acpi_device_lock);
1422         return 0;
1423 }
1424
1425
1426 static int acpi_device_resume(struct device * dev)
1427 {
1428         struct acpi_device * acpi_dev = to_acpi_dev(dev);
1429
1430         /*
1431          * For now, we should only register 1 generic device -
1432          * the ACPI root device - and from there, we walk the
1433          * tree of ACPI devices to resume each one using the
1434          * ACPI driver methods.
1435          */
1436         if (acpi_dev->handle == ACPI_ROOT_OBJECT)
1437                 root_resume(acpi_dev);
1438         return 0;
1439 }
1440
1441
1442 static struct bus_type acpi_bus_type = {
1443         .name           = "acpi",
1444         .suspend        = acpi_device_suspend,
1445         .resume         = acpi_device_resume,
1446 };
1447
1448
1449
1450 static int __init acpi_scan_init(void)
1451 {
1452         int result;
1453         struct acpi_bus_ops ops;
1454
1455
1456         if (acpi_disabled)
1457                 return 0;
1458
1459         result = kset_register(&acpi_namespace_kset);
1460         if (result < 0)
1461                 printk(KERN_ERR PREFIX "kset_register error: %d\n", result);
1462
1463         result = bus_register(&acpi_bus_type);
1464         if (result) {
1465                 /* We don't want to quit even if we failed to add suspend/resume */
1466                 printk(KERN_ERR PREFIX "Could not register bus type\n");
1467         }
1468
1469         /*
1470          * Create the root device in the bus's device tree
1471          */
1472         result = acpi_add_single_object(&acpi_root, NULL, ACPI_ROOT_OBJECT,
1473                                         ACPI_BUS_TYPE_SYSTEM);
1474         if (result)
1475                 goto Done;
1476
1477         result = acpi_start_single_object(acpi_root);
1478         if (result)
1479                 goto Done;
1480
1481         acpi_root->dev.bus = &acpi_bus_type;
1482         snprintf(acpi_root->dev.bus_id, BUS_ID_SIZE, "%s", acpi_bus_type.name);
1483         result = device_register(&acpi_root->dev);
1484         if (result) {
1485                 /* We don't want to quit even if we failed to add suspend/resume */
1486                 printk(KERN_ERR PREFIX "Could not register device\n");
1487         }
1488
1489         /*
1490          * Enumerate devices in the ACPI namespace.
1491          */
1492         result = acpi_bus_scan_fixed(acpi_root);
1493         if (!result) {
1494                 memset(&ops, 0, sizeof(ops));
1495                 ops.acpi_op_add = 1;
1496                 ops.acpi_op_start = 1;
1497                 result = acpi_bus_scan(acpi_root, &ops);
1498         }
1499
1500         if (result)
1501                 acpi_device_unregister(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
1502
1503       Done:
1504         return result;
1505 }
1506
1507 subsys_initcall(acpi_scan_init);