Merge branches 'release' and 'ppc-workaround' into release
[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
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                    "LNXSYBUS"
20 #define ACPI_BUS_DEVICE_NAME            "System Bus"
21
22 static LIST_HEAD(acpi_device_list);
23 static LIST_HEAD(acpi_bus_id_list);
24 DEFINE_SPINLOCK(acpi_device_lock);
25 LIST_HEAD(acpi_wakeup_device_list);
26
27 struct acpi_device_bus_id{
28         char bus_id[15];
29         unsigned int instance_no;
30         struct list_head node;
31 };
32
33 /*
34  * Creates hid/cid(s) string needed for modalias and uevent
35  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
36  * char *modalias: "acpi:IBM0001:ACPI0001"
37 */
38 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
39                            int size)
40 {
41         int len;
42
43         if (!acpi_dev->flags.hardware_id)
44                 return -ENODEV;
45
46         len = snprintf(modalias, size, "acpi:%s:",
47                        acpi_dev->pnp.hardware_id);
48         if (len < 0 || len >= size)
49                 return -EINVAL;
50         size -= len;
51
52         if (acpi_dev->flags.compatible_ids) {
53                 struct acpi_compatible_id_list *cid_list;
54                 int i;
55                 int count;
56
57                 cid_list = acpi_dev->pnp.cid_list;
58                 for (i = 0; i < cid_list->count; i++) {
59                         count = snprintf(&modalias[len], size, "%s:",
60                                          cid_list->id[i].value);
61                         if (count < 0 || count >= size) {
62                                 printk(KERN_ERR "acpi: %s cid[%i] exceeds event buffer size",
63                                        acpi_dev->pnp.device_name, i);
64                                 break;
65                         }
66                         len += count;
67                         size -= count;
68                 }
69         }
70
71         modalias[len] = '\0';
72         return len;
73 }
74
75 static ssize_t
76 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
77         struct acpi_device *acpi_dev = to_acpi_device(dev);
78         int len;
79
80         /* Device has no HID and no CID or string is >1024 */
81         len = create_modalias(acpi_dev, buf, 1024);
82         if (len <= 0)
83                 return 0;
84         buf[len++] = '\n';
85         return len;
86 }
87 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
88
89 static int acpi_eject_operation(acpi_handle handle, int lockable)
90 {
91         struct acpi_object_list arg_list;
92         union acpi_object arg;
93         acpi_status status = AE_OK;
94
95         /*
96          * TBD: evaluate _PS3?
97          */
98
99         if (lockable) {
100                 arg_list.count = 1;
101                 arg_list.pointer = &arg;
102                 arg.type = ACPI_TYPE_INTEGER;
103                 arg.integer.value = 0;
104                 acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
105         }
106
107         arg_list.count = 1;
108         arg_list.pointer = &arg;
109         arg.type = ACPI_TYPE_INTEGER;
110         arg.integer.value = 1;
111
112         /*
113          * TBD: _EJD support.
114          */
115
116         status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
117         if (ACPI_FAILURE(status)) {
118                 return (-ENODEV);
119         }
120
121         return (0);
122 }
123
124 static ssize_t
125 acpi_eject_store(struct device *d, struct device_attribute *attr,
126                 const char *buf, size_t count)
127 {
128         int result;
129         int ret = count;
130         int islockable;
131         acpi_status status;
132         acpi_handle handle;
133         acpi_object_type type = 0;
134         struct acpi_device *acpi_device = to_acpi_device(d);
135
136         if ((!count) || (buf[0] != '1')) {
137                 return -EINVAL;
138         }
139 #ifndef FORCE_EJECT
140         if (acpi_device->driver == NULL) {
141                 ret = -ENODEV;
142                 goto err;
143         }
144 #endif
145         status = acpi_get_type(acpi_device->handle, &type);
146         if (ACPI_FAILURE(status) || (!acpi_device->flags.ejectable)) {
147                 ret = -ENODEV;
148                 goto err;
149         }
150
151         islockable = acpi_device->flags.lockable;
152         handle = acpi_device->handle;
153
154         result = acpi_bus_trim(acpi_device, 1);
155
156         if (!result)
157                 result = acpi_eject_operation(handle, islockable);
158
159         if (result) {
160                 ret = -EBUSY;
161         }
162       err:
163         return ret;
164 }
165
166 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
167
168 static ssize_t
169 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
170         struct acpi_device *acpi_dev = to_acpi_device(dev);
171
172         return sprintf(buf, "%s\n", acpi_dev->pnp.hardware_id);
173 }
174 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
175
176 static ssize_t
177 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
178         struct acpi_device *acpi_dev = to_acpi_device(dev);
179         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
180         int result;
181
182         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
183         if(result)
184                 goto end;
185
186         result = sprintf(buf, "%s\n", (char*)path.pointer);
187         kfree(path.pointer);
188   end:
189         return result;
190 }
191 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
192
193 static int acpi_device_setup_files(struct acpi_device *dev)
194 {
195         acpi_status status;
196         acpi_handle temp;
197         int result = 0;
198
199         /*
200          * Devices gotten from FADT don't have a "path" attribute
201          */
202         if(dev->handle) {
203                 result = device_create_file(&dev->dev, &dev_attr_path);
204                 if(result)
205                         goto end;
206         }
207
208         if(dev->flags.hardware_id) {
209                 result = device_create_file(&dev->dev, &dev_attr_hid);
210                 if(result)
211                         goto end;
212         }
213
214         if (dev->flags.hardware_id || dev->flags.compatible_ids){
215                 result = device_create_file(&dev->dev, &dev_attr_modalias);
216                 if(result)
217                         goto end;
218         }
219
220         /*
221          * If device has _EJ0, 'eject' file is created that is used to trigger
222          * hot-removal function from userland.
223          */
224         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
225         if (ACPI_SUCCESS(status))
226                 result = device_create_file(&dev->dev, &dev_attr_eject);
227   end:
228         return result;
229 }
230
231 static void acpi_device_remove_files(struct acpi_device *dev)
232 {
233         acpi_status status;
234         acpi_handle temp;
235
236         /*
237          * If device has _EJ0, 'eject' file is created that is used to trigger
238          * hot-removal function from userland.
239          */
240         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
241         if (ACPI_SUCCESS(status))
242                 device_remove_file(&dev->dev, &dev_attr_eject);
243
244         if (dev->flags.hardware_id || dev->flags.compatible_ids)
245                 device_remove_file(&dev->dev, &dev_attr_modalias);
246
247         if(dev->flags.hardware_id)
248                 device_remove_file(&dev->dev, &dev_attr_hid);
249         if(dev->handle)
250                 device_remove_file(&dev->dev, &dev_attr_path);
251 }
252 /* --------------------------------------------------------------------------
253                         ACPI Bus operations
254    -------------------------------------------------------------------------- */
255
256 int acpi_match_device_ids(struct acpi_device *device,
257                           const struct acpi_device_id *ids)
258 {
259         const struct acpi_device_id *id;
260
261         if (device->flags.hardware_id) {
262                 for (id = ids; id->id[0]; id++) {
263                         if (!strcmp((char*)id->id, device->pnp.hardware_id))
264                                 return 0;
265                 }
266         }
267
268         if (device->flags.compatible_ids) {
269                 struct acpi_compatible_id_list *cid_list = device->pnp.cid_list;
270                 int i;
271
272                 for (id = ids; id->id[0]; id++) {
273                         /* compare multiple _CID entries against driver ids */
274                         for (i = 0; i < cid_list->count; i++) {
275                                 if (!strcmp((char*)id->id,
276                                             cid_list->id[i].value))
277                                         return 0;
278                         }
279                 }
280         }
281
282         return -ENOENT;
283 }
284 EXPORT_SYMBOL(acpi_match_device_ids);
285
286 static void acpi_device_release(struct device *dev)
287 {
288         struct acpi_device *acpi_dev = to_acpi_device(dev);
289
290         kfree(acpi_dev->pnp.cid_list);
291         kfree(acpi_dev);
292 }
293
294 static int acpi_device_suspend(struct device *dev, pm_message_t state)
295 {
296         struct acpi_device *acpi_dev = to_acpi_device(dev);
297         struct acpi_driver *acpi_drv = acpi_dev->driver;
298
299         if (acpi_drv && acpi_drv->ops.suspend)
300                 return acpi_drv->ops.suspend(acpi_dev, state);
301         return 0;
302 }
303
304 static int acpi_device_resume(struct device *dev)
305 {
306         struct acpi_device *acpi_dev = to_acpi_device(dev);
307         struct acpi_driver *acpi_drv = acpi_dev->driver;
308
309         if (acpi_drv && acpi_drv->ops.resume)
310                 return acpi_drv->ops.resume(acpi_dev);
311         return 0;
312 }
313
314 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
315 {
316         struct acpi_device *acpi_dev = to_acpi_device(dev);
317         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
318
319         return !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
320 }
321
322 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
323 {
324         struct acpi_device *acpi_dev = to_acpi_device(dev);
325         int len;
326
327         if (add_uevent_var(env, "MODALIAS="))
328                 return -ENOMEM;
329         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
330                               sizeof(env->buf) - env->buflen);
331         if (len >= (sizeof(env->buf) - env->buflen))
332                 return -ENOMEM;
333         env->buflen += len;
334         return 0;
335 }
336
337 static int acpi_bus_driver_init(struct acpi_device *, struct acpi_driver *);
338 static int acpi_start_single_object(struct acpi_device *);
339 static int acpi_device_probe(struct device * dev)
340 {
341         struct acpi_device *acpi_dev = to_acpi_device(dev);
342         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
343         int ret;
344
345         ret = acpi_bus_driver_init(acpi_dev, acpi_drv);
346         if (!ret) {
347                 if (acpi_dev->bus_ops.acpi_op_start)
348                         acpi_start_single_object(acpi_dev);
349                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
350                         "Found driver [%s] for device [%s]\n",
351                         acpi_drv->name, acpi_dev->pnp.bus_id));
352                 get_device(dev);
353         }
354         return ret;
355 }
356
357 static int acpi_device_remove(struct device * dev)
358 {
359         struct acpi_device *acpi_dev = to_acpi_device(dev);
360         struct acpi_driver *acpi_drv = acpi_dev->driver;
361
362         if (acpi_drv) {
363                 if (acpi_drv->ops.stop)
364                         acpi_drv->ops.stop(acpi_dev, acpi_dev->removal_type);
365                 if (acpi_drv->ops.remove)
366                         acpi_drv->ops.remove(acpi_dev, acpi_dev->removal_type);
367         }
368         acpi_dev->driver = NULL;
369         acpi_driver_data(dev) = NULL;
370
371         put_device(dev);
372         return 0;
373 }
374
375 static void acpi_device_shutdown(struct device *dev)
376 {
377         struct acpi_device *acpi_dev = to_acpi_device(dev);
378         struct acpi_driver *acpi_drv = acpi_dev->driver;
379
380         if (acpi_drv && acpi_drv->ops.shutdown)
381                 acpi_drv->ops.shutdown(acpi_dev);
382
383         return ;
384 }
385
386 struct bus_type acpi_bus_type = {
387         .name           = "acpi",
388         .suspend        = acpi_device_suspend,
389         .resume         = acpi_device_resume,
390         .shutdown       = acpi_device_shutdown,
391         .match          = acpi_bus_match,
392         .probe          = acpi_device_probe,
393         .remove         = acpi_device_remove,
394         .uevent         = acpi_device_uevent,
395 };
396
397 static int acpi_device_register(struct acpi_device *device,
398                                  struct acpi_device *parent)
399 {
400         int result;
401         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
402         int found = 0;
403         /*
404          * Linkage
405          * -------
406          * Link this device to its parent and siblings.
407          */
408         INIT_LIST_HEAD(&device->children);
409         INIT_LIST_HEAD(&device->node);
410         INIT_LIST_HEAD(&device->g_list);
411         INIT_LIST_HEAD(&device->wakeup_list);
412
413         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
414         if (!new_bus_id) {
415                 printk(KERN_ERR PREFIX "Memory allocation error\n");
416                 return -ENOMEM;
417         }
418
419         spin_lock(&acpi_device_lock);
420         /*
421          * Find suitable bus_id and instance number in acpi_bus_id_list
422          * If failed, create one and link it into acpi_bus_id_list
423          */
424         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
425                 if(!strcmp(acpi_device_bus_id->bus_id, device->flags.hardware_id? device->pnp.hardware_id : "device")) {
426                         acpi_device_bus_id->instance_no ++;
427                         found = 1;
428                         kfree(new_bus_id);
429                         break;
430                 }
431         }
432         if(!found) {
433                 acpi_device_bus_id = new_bus_id;
434                 strcpy(acpi_device_bus_id->bus_id, device->flags.hardware_id ? device->pnp.hardware_id : "device");
435                 acpi_device_bus_id->instance_no = 0;
436                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
437         }
438         sprintf(device->dev.bus_id, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
439
440         if (device->parent) {
441                 list_add_tail(&device->node, &device->parent->children);
442                 list_add_tail(&device->g_list, &device->parent->g_list);
443         } else
444                 list_add_tail(&device->g_list, &acpi_device_list);
445         if (device->wakeup.flags.valid)
446                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
447         spin_unlock(&acpi_device_lock);
448
449         if (device->parent)
450                 device->dev.parent = &parent->dev;
451         device->dev.bus = &acpi_bus_type;
452         device_initialize(&device->dev);
453         device->dev.release = &acpi_device_release;
454         result = device_add(&device->dev);
455         if(result) {
456                 printk("Error adding device %s", device->dev.bus_id);
457                 goto end;
458         }
459
460         result = acpi_device_setup_files(device);
461         if(result)
462                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error creating sysfs interface for device %s\n", device->dev.bus_id));
463
464         device->removal_type = ACPI_BUS_REMOVAL_NORMAL;
465         return 0;
466   end:
467         spin_lock(&acpi_device_lock);
468         if (device->parent) {
469                 list_del(&device->node);
470                 list_del(&device->g_list);
471         } else
472                 list_del(&device->g_list);
473         list_del(&device->wakeup_list);
474         spin_unlock(&acpi_device_lock);
475         return result;
476 }
477
478 static void acpi_device_unregister(struct acpi_device *device, int type)
479 {
480         spin_lock(&acpi_device_lock);
481         if (device->parent) {
482                 list_del(&device->node);
483                 list_del(&device->g_list);
484         } else
485                 list_del(&device->g_list);
486
487         list_del(&device->wakeup_list);
488         spin_unlock(&acpi_device_lock);
489
490         acpi_detach_data(device->handle, acpi_bus_data_handler);
491
492         acpi_device_remove_files(device);
493         device_unregister(&device->dev);
494 }
495
496 /* --------------------------------------------------------------------------
497                                  Driver Management
498    -------------------------------------------------------------------------- */
499 /**
500  * acpi_bus_driver_init - add a device to a driver
501  * @device: the device to add and initialize
502  * @driver: driver for the device
503  *
504  * Used to initialize a device via its device driver.  Called whenever a 
505  * driver is bound to a device.  Invokes the driver's add() ops.
506  */
507 static int
508 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
509 {
510         int result = 0;
511
512
513         if (!device || !driver)
514                 return -EINVAL;
515
516         if (!driver->ops.add)
517                 return -ENOSYS;
518
519         result = driver->ops.add(device);
520         if (result) {
521                 device->driver = NULL;
522                 acpi_driver_data(device) = NULL;
523                 return result;
524         }
525
526         device->driver = driver;
527
528         /*
529          * TBD - Configuration Management: Assign resources to device based
530          * upon possible configuration and currently allocated resources.
531          */
532
533         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
534                           "Driver successfully bound to device\n"));
535         return 0;
536 }
537
538 static int acpi_start_single_object(struct acpi_device *device)
539 {
540         int result = 0;
541         struct acpi_driver *driver;
542
543
544         if (!(driver = device->driver))
545                 return 0;
546
547         if (driver->ops.start) {
548                 result = driver->ops.start(device);
549                 if (result && driver->ops.remove)
550                         driver->ops.remove(device, ACPI_BUS_REMOVAL_NORMAL);
551         }
552
553         return result;
554 }
555
556 /**
557  * acpi_bus_register_driver - register a driver with the ACPI bus
558  * @driver: driver being registered
559  *
560  * Registers a driver with the ACPI bus.  Searches the namespace for all
561  * devices that match the driver's criteria and binds.  Returns zero for
562  * success or a negative error status for failure.
563  */
564 int acpi_bus_register_driver(struct acpi_driver *driver)
565 {
566         int ret;
567
568         if (acpi_disabled)
569                 return -ENODEV;
570         driver->drv.name = driver->name;
571         driver->drv.bus = &acpi_bus_type;
572         driver->drv.owner = driver->owner;
573
574         ret = driver_register(&driver->drv);
575         return ret;
576 }
577
578 EXPORT_SYMBOL(acpi_bus_register_driver);
579
580 /**
581  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
582  * @driver: driver to unregister
583  *
584  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
585  * devices that match the driver's criteria and unbinds.
586  */
587 void acpi_bus_unregister_driver(struct acpi_driver *driver)
588 {
589         driver_unregister(&driver->drv);
590 }
591
592 EXPORT_SYMBOL(acpi_bus_unregister_driver);
593
594 /* --------------------------------------------------------------------------
595                                  Device Enumeration
596    -------------------------------------------------------------------------- */
597 acpi_status
598 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
599 {
600         acpi_status status;
601         acpi_handle tmp;
602         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
603         union acpi_object *obj;
604
605         status = acpi_get_handle(handle, "_EJD", &tmp);
606         if (ACPI_FAILURE(status))
607                 return status;
608
609         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
610         if (ACPI_SUCCESS(status)) {
611                 obj = buffer.pointer;
612                 status = acpi_get_handle(NULL, obj->string.pointer, ejd);
613                 kfree(buffer.pointer);
614         }
615         return status;
616 }
617 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
618
619 void acpi_bus_data_handler(acpi_handle handle, u32 function, void *context)
620 {
621
622         /* TBD */
623
624         return;
625 }
626
627 static int acpi_bus_get_perf_flags(struct acpi_device *device)
628 {
629         device->performance.state = ACPI_STATE_UNKNOWN;
630         return 0;
631 }
632
633 static acpi_status
634 acpi_bus_extract_wakeup_device_power_package(struct acpi_device *device,
635                                              union acpi_object *package)
636 {
637         int i = 0;
638         union acpi_object *element = NULL;
639
640         if (!device || !package || (package->package.count < 2))
641                 return AE_BAD_PARAMETER;
642
643         element = &(package->package.elements[0]);
644         if (!element)
645                 return AE_BAD_PARAMETER;
646         if (element->type == ACPI_TYPE_PACKAGE) {
647                 if ((element->package.count < 2) ||
648                     (element->package.elements[0].type !=
649                      ACPI_TYPE_LOCAL_REFERENCE)
650                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
651                         return AE_BAD_DATA;
652                 device->wakeup.gpe_device =
653                     element->package.elements[0].reference.handle;
654                 device->wakeup.gpe_number =
655                     (u32) element->package.elements[1].integer.value;
656         } else if (element->type == ACPI_TYPE_INTEGER) {
657                 device->wakeup.gpe_number = element->integer.value;
658         } else
659                 return AE_BAD_DATA;
660
661         element = &(package->package.elements[1]);
662         if (element->type != ACPI_TYPE_INTEGER) {
663                 return AE_BAD_DATA;
664         }
665         device->wakeup.sleep_state = element->integer.value;
666
667         if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
668                 return AE_NO_MEMORY;
669         }
670         device->wakeup.resources.count = package->package.count - 2;
671         for (i = 0; i < device->wakeup.resources.count; i++) {
672                 element = &(package->package.elements[i + 2]);
673                 if (element->type != ACPI_TYPE_ANY) {
674                         return AE_BAD_DATA;
675                 }
676
677                 device->wakeup.resources.handles[i] = element->reference.handle;
678         }
679
680         return AE_OK;
681 }
682
683 static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
684 {
685         acpi_status status = 0;
686         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
687         union acpi_object *package = NULL;
688
689         struct acpi_device_id button_device_ids[] = {
690                 {"PNP0C0D", 0},
691                 {"PNP0C0C", 0},
692                 {"PNP0C0E", 0},
693                 {"", 0},
694         };
695
696
697         /* _PRW */
698         status = acpi_evaluate_object(device->handle, "_PRW", NULL, &buffer);
699         if (ACPI_FAILURE(status)) {
700                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
701                 goto end;
702         }
703
704         package = (union acpi_object *)buffer.pointer;
705         status = acpi_bus_extract_wakeup_device_power_package(device, package);
706         if (ACPI_FAILURE(status)) {
707                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _PRW package"));
708                 goto end;
709         }
710
711         kfree(buffer.pointer);
712
713         device->wakeup.flags.valid = 1;
714         /* Power button, Lid switch always enable wakeup */
715         if (!acpi_match_device_ids(device, button_device_ids))
716                 device->wakeup.flags.run_wake = 1;
717
718       end:
719         if (ACPI_FAILURE(status))
720                 device->flags.wake_capable = 0;
721         return 0;
722 }
723
724 static int acpi_bus_get_power_flags(struct acpi_device *device)
725 {
726         acpi_status status = 0;
727         acpi_handle handle = NULL;
728         u32 i = 0;
729
730
731         /*
732          * Power Management Flags
733          */
734         status = acpi_get_handle(device->handle, "_PSC", &handle);
735         if (ACPI_SUCCESS(status))
736                 device->power.flags.explicit_get = 1;
737         status = acpi_get_handle(device->handle, "_IRC", &handle);
738         if (ACPI_SUCCESS(status))
739                 device->power.flags.inrush_current = 1;
740
741         /*
742          * Enumerate supported power management states
743          */
744         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
745                 struct acpi_device_power_state *ps = &device->power.states[i];
746                 char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
747
748                 /* Evaluate "_PRx" to se if power resources are referenced */
749                 acpi_evaluate_reference(device->handle, object_name, NULL,
750                                         &ps->resources);
751                 if (ps->resources.count) {
752                         device->power.flags.power_resources = 1;
753                         ps->flags.valid = 1;
754                 }
755
756                 /* Evaluate "_PSx" to see if we can do explicit sets */
757                 object_name[2] = 'S';
758                 status = acpi_get_handle(device->handle, object_name, &handle);
759                 if (ACPI_SUCCESS(status)) {
760                         ps->flags.explicit_set = 1;
761                         ps->flags.valid = 1;
762                 }
763
764                 /* State is valid if we have some power control */
765                 if (ps->resources.count || ps->flags.explicit_set)
766                         ps->flags.valid = 1;
767
768                 ps->power = -1; /* Unknown - driver assigned */
769                 ps->latency = -1;       /* Unknown - driver assigned */
770         }
771
772         /* Set defaults for D0 and D3 states (always valid) */
773         device->power.states[ACPI_STATE_D0].flags.valid = 1;
774         device->power.states[ACPI_STATE_D0].power = 100;
775         device->power.states[ACPI_STATE_D3].flags.valid = 1;
776         device->power.states[ACPI_STATE_D3].power = 0;
777
778         /* TBD: System wake support and resource requirements. */
779
780         device->power.state = ACPI_STATE_UNKNOWN;
781
782         return 0;
783 }
784
785 static int acpi_bus_get_flags(struct acpi_device *device)
786 {
787         acpi_status status = AE_OK;
788         acpi_handle temp = NULL;
789
790
791         /* Presence of _STA indicates 'dynamic_status' */
792         status = acpi_get_handle(device->handle, "_STA", &temp);
793         if (ACPI_SUCCESS(status))
794                 device->flags.dynamic_status = 1;
795
796         /* Presence of _CID indicates 'compatible_ids' */
797         status = acpi_get_handle(device->handle, "_CID", &temp);
798         if (ACPI_SUCCESS(status))
799                 device->flags.compatible_ids = 1;
800
801         /* Presence of _RMV indicates 'removable' */
802         status = acpi_get_handle(device->handle, "_RMV", &temp);
803         if (ACPI_SUCCESS(status))
804                 device->flags.removable = 1;
805
806         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
807         status = acpi_get_handle(device->handle, "_EJD", &temp);
808         if (ACPI_SUCCESS(status))
809                 device->flags.ejectable = 1;
810         else {
811                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
812                 if (ACPI_SUCCESS(status))
813                         device->flags.ejectable = 1;
814         }
815
816         /* Presence of _LCK indicates 'lockable' */
817         status = acpi_get_handle(device->handle, "_LCK", &temp);
818         if (ACPI_SUCCESS(status))
819                 device->flags.lockable = 1;
820
821         /* Presence of _PS0|_PR0 indicates 'power manageable' */
822         status = acpi_get_handle(device->handle, "_PS0", &temp);
823         if (ACPI_FAILURE(status))
824                 status = acpi_get_handle(device->handle, "_PR0", &temp);
825         if (ACPI_SUCCESS(status))
826                 device->flags.power_manageable = 1;
827
828         /* Presence of _PRW indicates wake capable */
829         status = acpi_get_handle(device->handle, "_PRW", &temp);
830         if (ACPI_SUCCESS(status))
831                 device->flags.wake_capable = 1;
832
833         /* TBD: Performance management */
834
835         return 0;
836 }
837
838 static void acpi_device_get_busid(struct acpi_device *device,
839                                   acpi_handle handle, int type)
840 {
841         char bus_id[5] = { '?', 0 };
842         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
843         int i = 0;
844
845         /*
846          * Bus ID
847          * ------
848          * The device's Bus ID is simply the object name.
849          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
850          */
851         switch (type) {
852         case ACPI_BUS_TYPE_SYSTEM:
853                 strcpy(device->pnp.bus_id, "ACPI");
854                 break;
855         case ACPI_BUS_TYPE_POWER_BUTTON:
856                 strcpy(device->pnp.bus_id, "PWRF");
857                 break;
858         case ACPI_BUS_TYPE_SLEEP_BUTTON:
859                 strcpy(device->pnp.bus_id, "SLPF");
860                 break;
861         default:
862                 acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
863                 /* Clean up trailing underscores (if any) */
864                 for (i = 3; i > 1; i--) {
865                         if (bus_id[i] == '_')
866                                 bus_id[i] = '\0';
867                         else
868                                 break;
869                 }
870                 strcpy(device->pnp.bus_id, bus_id);
871                 break;
872         }
873 }
874
875 static int
876 acpi_video_bus_match(struct acpi_device *device)
877 {
878         acpi_handle h_dummy1;
879         acpi_handle h_dummy2;
880         acpi_handle h_dummy3;
881
882
883         if (!device)
884                 return -EINVAL;
885
886         /* Since there is no HID, CID for ACPI Video drivers, we have
887          * to check well known required nodes for each feature we support.
888          */
889
890         /* Does this device able to support video switching ? */
891         if (ACPI_SUCCESS(acpi_get_handle(device->handle, "_DOD", &h_dummy1)) &&
892             ACPI_SUCCESS(acpi_get_handle(device->handle, "_DOS", &h_dummy2)))
893                 return 0;
894
895         /* Does this device able to retrieve a video ROM ? */
896         if (ACPI_SUCCESS(acpi_get_handle(device->handle, "_ROM", &h_dummy1)))
897                 return 0;
898
899         /* Does this device able to configure which video head to be POSTed ? */
900         if (ACPI_SUCCESS(acpi_get_handle(device->handle, "_VPO", &h_dummy1)) &&
901             ACPI_SUCCESS(acpi_get_handle(device->handle, "_GPD", &h_dummy2)) &&
902             ACPI_SUCCESS(acpi_get_handle(device->handle, "_SPD", &h_dummy3)))
903                 return 0;
904
905         return -ENODEV;
906 }
907
908 /*
909  * acpi_bay_match - see if a device is an ejectable driver bay
910  *
911  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
912  * then we can safely call it an ejectable drive bay
913  */
914 static int acpi_bay_match(struct acpi_device *device){
915         acpi_status status;
916         acpi_handle handle;
917         acpi_handle tmp;
918         acpi_handle phandle;
919
920         handle = device->handle;
921
922         status = acpi_get_handle(handle, "_EJ0", &tmp);
923         if (ACPI_FAILURE(status))
924                 return -ENODEV;
925
926         if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
927                 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
928                 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
929                 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
930                 return 0;
931
932         if (acpi_get_parent(handle, &phandle))
933                 return -ENODEV;
934
935         if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
936                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
937                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
938                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
939                 return 0;
940
941         return -ENODEV;
942 }
943
944 /*
945  * acpi_dock_match - see if a device has a _DCK method
946  */
947 static int acpi_dock_match(struct acpi_device *device)
948 {
949         acpi_handle tmp;
950         return acpi_get_handle(device->handle, "_DCK", &tmp);
951 }
952
953 static void acpi_device_set_id(struct acpi_device *device,
954                                struct acpi_device *parent, acpi_handle handle,
955                                int type)
956 {
957         struct acpi_device_info *info;
958         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
959         char *hid = NULL;
960         char *uid = NULL;
961         struct acpi_compatible_id_list *cid_list = NULL;
962         const char *cid_add = NULL;
963         acpi_status status;
964
965         switch (type) {
966         case ACPI_BUS_TYPE_DEVICE:
967                 status = acpi_get_object_info(handle, &buffer);
968                 if (ACPI_FAILURE(status)) {
969                         printk("%s: Error reading device info\n", __FUNCTION__);
970                         return;
971                 }
972
973                 info = buffer.pointer;
974                 if (info->valid & ACPI_VALID_HID)
975                         hid = info->hardware_id.value;
976                 if (info->valid & ACPI_VALID_UID)
977                         uid = info->unique_id.value;
978                 if (info->valid & ACPI_VALID_CID)
979                         cid_list = &info->compatibility_id;
980                 if (info->valid & ACPI_VALID_ADR) {
981                         device->pnp.bus_address = info->address;
982                         device->flags.bus_address = 1;
983                 }
984
985                 /* If we have a video/bay/dock device, add our selfdefined
986                    HID to the CID list. Like that the video/bay/dock drivers
987                    will get autoloaded and the device might still match
988                    against another driver.
989                 */
990                 if (ACPI_SUCCESS(acpi_video_bus_match(device)))
991                         cid_add = ACPI_VIDEO_HID;
992                 else if (ACPI_SUCCESS(acpi_bay_match(device)))
993                         cid_add = ACPI_BAY_HID;
994                 else if (ACPI_SUCCESS(acpi_dock_match(device)))
995                         cid_add = ACPI_DOCK_HID;
996
997                 break;
998         case ACPI_BUS_TYPE_POWER:
999                 hid = ACPI_POWER_HID;
1000                 break;
1001         case ACPI_BUS_TYPE_PROCESSOR:
1002                 hid = ACPI_PROCESSOR_HID;
1003                 break;
1004         case ACPI_BUS_TYPE_SYSTEM:
1005                 hid = ACPI_SYSTEM_HID;
1006                 break;
1007         case ACPI_BUS_TYPE_THERMAL:
1008                 hid = ACPI_THERMAL_HID;
1009                 break;
1010         case ACPI_BUS_TYPE_POWER_BUTTON:
1011                 hid = ACPI_BUTTON_HID_POWERF;
1012                 break;
1013         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1014                 hid = ACPI_BUTTON_HID_SLEEPF;
1015                 break;
1016         }
1017
1018         /* 
1019          * \_SB
1020          * ----
1021          * Fix for the system root bus device -- the only root-level device.
1022          */
1023         if (((acpi_handle)parent == ACPI_ROOT_OBJECT) && (type == ACPI_BUS_TYPE_DEVICE)) {
1024                 hid = ACPI_BUS_HID;
1025                 strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
1026                 strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
1027         }
1028
1029         if (hid) {
1030                 strcpy(device->pnp.hardware_id, hid);
1031                 device->flags.hardware_id = 1;
1032         }
1033         if (uid) {
1034                 strcpy(device->pnp.unique_id, uid);
1035                 device->flags.unique_id = 1;
1036         }
1037         if (cid_list || cid_add) {
1038                 struct  acpi_compatible_id_list *list;
1039                 int size = 0;
1040                 int count = 0;
1041
1042                 if (cid_list) {
1043                         size = cid_list->size;
1044                 } else if (cid_add) {
1045                         size = sizeof(struct acpi_compatible_id_list);
1046                         cid_list = ACPI_ALLOCATE_ZEROED((acpi_size) size);
1047                         if (!cid_list) {
1048                                 printk(KERN_ERR "Memory allocation error\n");
1049                                 kfree(buffer.pointer);
1050                                 return;
1051                         } else {
1052                                 cid_list->count = 0;
1053                                 cid_list->size = size;
1054                         }
1055                 }
1056                 if (cid_add)
1057                         size += sizeof(struct acpi_compatible_id);
1058                 list = kmalloc(size, GFP_KERNEL);
1059
1060                 if (list) {
1061                         if (cid_list) {
1062                                 memcpy(list, cid_list, cid_list->size);
1063                                 count = cid_list->count;
1064                         }
1065                         if (cid_add) {
1066                                 strncpy(list->id[count].value, cid_add,
1067                                         ACPI_MAX_CID_LENGTH);
1068                                 count++;
1069                                 device->flags.compatible_ids = 1;
1070                         }
1071                         list->size = size;
1072                         list->count = count;
1073                         device->pnp.cid_list = list;
1074                 } else
1075                         printk(KERN_ERR "Memory allocation error\n");
1076         }
1077
1078         kfree(buffer.pointer);
1079 }
1080
1081 static int acpi_device_set_context(struct acpi_device *device, int type)
1082 {
1083         acpi_status status = AE_OK;
1084         int result = 0;
1085         /*
1086          * Context
1087          * -------
1088          * Attach this 'struct acpi_device' to the ACPI object.  This makes
1089          * resolutions from handle->device very efficient.  Note that we need
1090          * to be careful with fixed-feature devices as they all attach to the
1091          * root object.
1092          */
1093         if (type != ACPI_BUS_TYPE_POWER_BUTTON &&
1094             type != ACPI_BUS_TYPE_SLEEP_BUTTON) {
1095                 status = acpi_attach_data(device->handle,
1096                                           acpi_bus_data_handler, device);
1097
1098                 if (ACPI_FAILURE(status)) {
1099                         printk("Error attaching device data\n");
1100                         result = -ENODEV;
1101                 }
1102         }
1103         return result;
1104 }
1105
1106 static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
1107 {
1108         if (!dev)
1109                 return -EINVAL;
1110
1111         dev->removal_type = ACPI_BUS_REMOVAL_EJECT;
1112         device_release_driver(&dev->dev);
1113
1114         if (!rmdevice)
1115                 return 0;
1116
1117         /*
1118          * unbind _ADR-Based Devices when hot removal
1119          */
1120         if (dev->flags.bus_address) {
1121                 if ((dev->parent) && (dev->parent->ops.unbind))
1122                         dev->parent->ops.unbind(dev);
1123         }
1124         acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
1125
1126         return 0;
1127 }
1128
1129 static int
1130 acpi_is_child_device(struct acpi_device *device,
1131                         int (*matcher)(struct acpi_device *))
1132 {
1133         int result = -ENODEV;
1134
1135         do {
1136                 if (ACPI_SUCCESS(matcher(device)))
1137                         return AE_OK;
1138         } while ((device = device->parent));
1139
1140         return result;
1141 }
1142
1143 static int
1144 acpi_add_single_object(struct acpi_device **child,
1145                        struct acpi_device *parent, acpi_handle handle, int type,
1146                         struct acpi_bus_ops *ops)
1147 {
1148         int result = 0;
1149         struct acpi_device *device = NULL;
1150
1151
1152         if (!child)
1153                 return -EINVAL;
1154
1155         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1156         if (!device) {
1157                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1158                 return -ENOMEM;
1159         }
1160
1161         device->handle = handle;
1162         device->parent = parent;
1163         device->bus_ops = *ops; /* workround for not call .start */
1164
1165
1166         acpi_device_get_busid(device, handle, type);
1167
1168         /*
1169          * Flags
1170          * -----
1171          * Get prior to calling acpi_bus_get_status() so we know whether
1172          * or not _STA is present.  Note that we only look for object
1173          * handles -- cannot evaluate objects until we know the device is
1174          * present and properly initialized.
1175          */
1176         result = acpi_bus_get_flags(device);
1177         if (result)
1178                 goto end;
1179
1180         /*
1181          * Status
1182          * ------
1183          * See if the device is present.  We always assume that non-Device
1184          * and non-Processor objects (e.g. thermal zones, power resources,
1185          * etc.) are present, functioning, etc. (at least when parent object
1186          * is present).  Note that _STA has a different meaning for some
1187          * objects (e.g. power resources) so we need to be careful how we use
1188          * it.
1189          */
1190         switch (type) {
1191         case ACPI_BUS_TYPE_PROCESSOR:
1192         case ACPI_BUS_TYPE_DEVICE:
1193                 result = acpi_bus_get_status(device);
1194                 if (ACPI_FAILURE(result)) {
1195                         result = -ENODEV;
1196                         goto end;
1197                 }
1198                 if (!device->status.present) {
1199                         /* Bay and dock should be handled even if absent */
1200                         if (!ACPI_SUCCESS(
1201                              acpi_is_child_device(device, acpi_bay_match)) &&
1202                             !ACPI_SUCCESS(
1203                              acpi_is_child_device(device, acpi_dock_match))) {
1204                                         result = -ENODEV;
1205                                         goto end;
1206                         }
1207                 }
1208                 break;
1209         default:
1210                 STRUCT_TO_INT(device->status) =
1211                     ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED |
1212                     ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING;
1213                 break;
1214         }
1215
1216         /*
1217          * Initialize Device
1218          * -----------------
1219          * TBD: Synch with Core's enumeration/initialization process.
1220          */
1221
1222         /*
1223          * Hardware ID, Unique ID, & Bus Address
1224          * -------------------------------------
1225          */
1226         acpi_device_set_id(device, parent, handle, type);
1227
1228         /*
1229          * Power Management
1230          * ----------------
1231          */
1232         if (device->flags.power_manageable) {
1233                 result = acpi_bus_get_power_flags(device);
1234                 if (result)
1235                         goto end;
1236         }
1237
1238         /*
1239          * Wakeup device management
1240          *-----------------------
1241          */
1242         if (device->flags.wake_capable) {
1243                 result = acpi_bus_get_wakeup_device_flags(device);
1244                 if (result)
1245                         goto end;
1246         }
1247
1248         /*
1249          * Performance Management
1250          * ----------------------
1251          */
1252         if (device->flags.performance_manageable) {
1253                 result = acpi_bus_get_perf_flags(device);
1254                 if (result)
1255                         goto end;
1256         }
1257
1258         if ((result = acpi_device_set_context(device, type)))
1259                 goto end;
1260
1261         result = acpi_device_register(device, parent);
1262
1263         /*
1264          * Bind _ADR-Based Devices when hot add
1265          */
1266         if (device->flags.bus_address) {
1267                 if (device->parent && device->parent->ops.bind)
1268                         device->parent->ops.bind(device);
1269         }
1270
1271       end:
1272         if (!result)
1273                 *child = device;
1274         else {
1275                 kfree(device->pnp.cid_list);
1276                 kfree(device);
1277         }
1278
1279         return result;
1280 }
1281
1282 static int acpi_bus_scan(struct acpi_device *start, struct acpi_bus_ops *ops)
1283 {
1284         acpi_status status = AE_OK;
1285         struct acpi_device *parent = NULL;
1286         struct acpi_device *child = NULL;
1287         acpi_handle phandle = NULL;
1288         acpi_handle chandle = NULL;
1289         acpi_object_type type = 0;
1290         u32 level = 1;
1291
1292
1293         if (!start)
1294                 return -EINVAL;
1295
1296         parent = start;
1297         phandle = start->handle;
1298
1299         /*
1300          * Parse through the ACPI namespace, identify all 'devices', and
1301          * create a new 'struct acpi_device' for each.
1302          */
1303         while ((level > 0) && parent) {
1304
1305                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1306                                               chandle, &chandle);
1307
1308                 /*
1309                  * If this scope is exhausted then move our way back up.
1310                  */
1311                 if (ACPI_FAILURE(status)) {
1312                         level--;
1313                         chandle = phandle;
1314                         acpi_get_parent(phandle, &phandle);
1315                         if (parent->parent)
1316                                 parent = parent->parent;
1317                         continue;
1318                 }
1319
1320                 status = acpi_get_type(chandle, &type);
1321                 if (ACPI_FAILURE(status))
1322                         continue;
1323
1324                 /*
1325                  * If this is a scope object then parse it (depth-first).
1326                  */
1327                 if (type == ACPI_TYPE_LOCAL_SCOPE) {
1328                         level++;
1329                         phandle = chandle;
1330                         chandle = NULL;
1331                         continue;
1332                 }
1333
1334                 /*
1335                  * We're only interested in objects that we consider 'devices'.
1336                  */
1337                 switch (type) {
1338                 case ACPI_TYPE_DEVICE:
1339                         type = ACPI_BUS_TYPE_DEVICE;
1340                         break;
1341                 case ACPI_TYPE_PROCESSOR:
1342                         type = ACPI_BUS_TYPE_PROCESSOR;
1343                         break;
1344                 case ACPI_TYPE_THERMAL:
1345                         type = ACPI_BUS_TYPE_THERMAL;
1346                         break;
1347                 case ACPI_TYPE_POWER:
1348                         type = ACPI_BUS_TYPE_POWER;
1349                         break;
1350                 default:
1351                         continue;
1352                 }
1353
1354                 if (ops->acpi_op_add)
1355                         status = acpi_add_single_object(&child, parent,
1356                                 chandle, type, ops);
1357                 else
1358                         status = acpi_bus_get_device(chandle, &child);
1359
1360                 if (ACPI_FAILURE(status))
1361                         continue;
1362
1363                 if (ops->acpi_op_start && !(ops->acpi_op_add)) {
1364                         status = acpi_start_single_object(child);
1365                         if (ACPI_FAILURE(status))
1366                                 continue;
1367                 }
1368
1369                 /*
1370                  * If the device is present, enabled, and functioning then
1371                  * parse its scope (depth-first).  Note that we need to
1372                  * represent absent devices to facilitate PnP notifications
1373                  * -- but only the subtree head (not all of its children,
1374                  * which will be enumerated when the parent is inserted).
1375                  *
1376                  * TBD: Need notifications and other detection mechanisms
1377                  *      in place before we can fully implement this.
1378                  */
1379                 if (child->status.present) {
1380                         status = acpi_get_next_object(ACPI_TYPE_ANY, chandle,
1381                                                       NULL, NULL);
1382                         if (ACPI_SUCCESS(status)) {
1383                                 level++;
1384                                 phandle = chandle;
1385                                 chandle = NULL;
1386                                 parent = child;
1387                         }
1388                 }
1389         }
1390
1391         return 0;
1392 }
1393
1394 int
1395 acpi_bus_add(struct acpi_device **child,
1396              struct acpi_device *parent, acpi_handle handle, int type)
1397 {
1398         int result;
1399         struct acpi_bus_ops ops;
1400
1401         memset(&ops, 0, sizeof(ops));
1402         ops.acpi_op_add = 1;
1403
1404         result = acpi_add_single_object(child, parent, handle, type, &ops);
1405         if (!result)
1406                 result = acpi_bus_scan(*child, &ops);
1407
1408         return result;
1409 }
1410
1411 EXPORT_SYMBOL(acpi_bus_add);
1412
1413 int acpi_bus_start(struct acpi_device *device)
1414 {
1415         int result;
1416         struct acpi_bus_ops ops;
1417
1418
1419         if (!device)
1420                 return -EINVAL;
1421
1422         result = acpi_start_single_object(device);
1423         if (!result) {
1424                 memset(&ops, 0, sizeof(ops));
1425                 ops.acpi_op_start = 1;
1426                 result = acpi_bus_scan(device, &ops);
1427         }
1428         return result;
1429 }
1430
1431 EXPORT_SYMBOL(acpi_bus_start);
1432
1433 int acpi_bus_trim(struct acpi_device *start, int rmdevice)
1434 {
1435         acpi_status status;
1436         struct acpi_device *parent, *child;
1437         acpi_handle phandle, chandle;
1438         acpi_object_type type;
1439         u32 level = 1;
1440         int err = 0;
1441
1442         parent = start;
1443         phandle = start->handle;
1444         child = chandle = NULL;
1445
1446         while ((level > 0) && parent && (!err)) {
1447                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1448                                               chandle, &chandle);
1449
1450                 /*
1451                  * If this scope is exhausted then move our way back up.
1452                  */
1453                 if (ACPI_FAILURE(status)) {
1454                         level--;
1455                         chandle = phandle;
1456                         acpi_get_parent(phandle, &phandle);
1457                         child = parent;
1458                         parent = parent->parent;
1459
1460                         if (level == 0)
1461                                 err = acpi_bus_remove(child, rmdevice);
1462                         else
1463                                 err = acpi_bus_remove(child, 1);
1464
1465                         continue;
1466                 }
1467
1468                 status = acpi_get_type(chandle, &type);
1469                 if (ACPI_FAILURE(status)) {
1470                         continue;
1471                 }
1472                 /*
1473                  * If there is a device corresponding to chandle then
1474                  * parse it (depth-first).
1475                  */
1476                 if (acpi_bus_get_device(chandle, &child) == 0) {
1477                         level++;
1478                         phandle = chandle;
1479                         chandle = NULL;
1480                         parent = child;
1481                 }
1482                 continue;
1483         }
1484         return err;
1485 }
1486 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1487
1488
1489 static int acpi_bus_scan_fixed(struct acpi_device *root)
1490 {
1491         int result = 0;
1492         struct acpi_device *device = NULL;
1493         struct acpi_bus_ops ops;
1494
1495         if (!root)
1496                 return -ENODEV;
1497
1498         memset(&ops, 0, sizeof(ops));
1499         ops.acpi_op_add = 1;
1500         ops.acpi_op_start = 1;
1501
1502         /*
1503          * Enumerate all fixed-feature devices.
1504          */
1505         if ((acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON) == 0) {
1506                 result = acpi_add_single_object(&device, acpi_root,
1507                                                 NULL,
1508                                                 ACPI_BUS_TYPE_POWER_BUTTON,
1509                                                 &ops);
1510         }
1511
1512         if ((acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON) == 0) {
1513                 result = acpi_add_single_object(&device, acpi_root,
1514                                                 NULL,
1515                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
1516                                                 &ops);
1517         }
1518
1519         return result;
1520 }
1521
1522 int __init acpi_boot_ec_enable(void);
1523
1524 static int __init acpi_scan_init(void)
1525 {
1526         int result;
1527         struct acpi_bus_ops ops;
1528
1529
1530         if (acpi_disabled)
1531                 return 0;
1532
1533         memset(&ops, 0, sizeof(ops));
1534         ops.acpi_op_add = 1;
1535         ops.acpi_op_start = 1;
1536
1537         result = bus_register(&acpi_bus_type);
1538         if (result) {
1539                 /* We don't want to quit even if we failed to add suspend/resume */
1540                 printk(KERN_ERR PREFIX "Could not register bus type\n");
1541         }
1542
1543         /*
1544          * Create the root device in the bus's device tree
1545          */
1546         result = acpi_add_single_object(&acpi_root, NULL, ACPI_ROOT_OBJECT,
1547                                         ACPI_BUS_TYPE_SYSTEM, &ops);
1548         if (result)
1549                 goto Done;
1550
1551         /*
1552          * Enumerate devices in the ACPI namespace.
1553          */
1554         result = acpi_bus_scan_fixed(acpi_root);
1555
1556         /* EC region might be needed at bus_scan, so enable it now */
1557         acpi_boot_ec_enable();
1558
1559         if (!result)
1560                 result = acpi_bus_scan(acpi_root, &ops);
1561
1562         if (result)
1563                 acpi_device_unregister(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
1564
1565       Done:
1566         return result;
1567 }
1568
1569 subsys_initcall(acpi_scan_init);