Merge branch 'release-2.6.27' of git://git.kernel.org/pub/scm/linux/kernel/git/ak...
[linux-2.6] / drivers / acpi / scan.c
1 /*
2  * scan.c - support for transforming the ACPI namespace into individual objects
3  */
4
5 #include <linux/module.h>
6 #include <linux/init.h>
7 #include <linux/kernel.h>
8 #include <linux/acpi.h>
9 #include <linux/signal.h>
10 #include <linux/kthread.h>
11
12 #include <acpi/acpi_drivers.h>
13 #include <acpi/acinterp.h>      /* for acpi_ex_eisa_id_to_string() */
14
15 #define _COMPONENT              ACPI_BUS_COMPONENT
16 ACPI_MODULE_NAME("scan");
17 #define STRUCT_TO_INT(s)        (*((int*)&s))
18 extern struct acpi_device *acpi_root;
19
20 #define ACPI_BUS_CLASS                  "system_bus"
21 #define ACPI_BUS_HID                    "LNXSYBUS"
22 #define ACPI_BUS_DEVICE_NAME            "System Bus"
23
24 static LIST_HEAD(acpi_device_list);
25 static LIST_HEAD(acpi_bus_id_list);
26 DEFINE_SPINLOCK(acpi_device_lock);
27 LIST_HEAD(acpi_wakeup_device_list);
28
29 struct acpi_device_bus_id{
30         char bus_id[15];
31         unsigned int instance_no;
32         struct list_head node;
33 };
34
35 /*
36  * Creates hid/cid(s) string needed for modalias and uevent
37  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
38  * char *modalias: "acpi:IBM0001:ACPI0001"
39 */
40 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
41                            int size)
42 {
43         int len;
44         int count;
45
46         if (!acpi_dev->flags.hardware_id && !acpi_dev->flags.compatible_ids)
47                 return -ENODEV;
48
49         len = snprintf(modalias, size, "acpi:");
50         size -= len;
51
52         if (acpi_dev->flags.hardware_id) {
53                 count = snprintf(&modalias[len], size, "%s:",
54                                  acpi_dev->pnp.hardware_id);
55                 if (count < 0 || count >= size)
56                         return -EINVAL;
57                 len += count;
58                 size -= count;
59         }
60
61         if (acpi_dev->flags.compatible_ids) {
62                 struct acpi_compatible_id_list *cid_list;
63                 int i;
64
65                 cid_list = acpi_dev->pnp.cid_list;
66                 for (i = 0; i < cid_list->count; i++) {
67                         count = snprintf(&modalias[len], size, "%s:",
68                                          cid_list->id[i].value);
69                         if (count < 0 || count >= size) {
70                                 printk(KERN_ERR PREFIX "%s cid[%i] exceeds event buffer size",
71                                        acpi_dev->pnp.device_name, i);
72                                 break;
73                         }
74                         len += count;
75                         size -= count;
76                 }
77         }
78
79         modalias[len] = '\0';
80         return len;
81 }
82
83 static ssize_t
84 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
85         struct acpi_device *acpi_dev = to_acpi_device(dev);
86         int len;
87
88         /* Device has no HID and no CID or string is >1024 */
89         len = create_modalias(acpi_dev, buf, 1024);
90         if (len <= 0)
91                 return 0;
92         buf[len++] = '\n';
93         return len;
94 }
95 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
96
97 static int acpi_bus_hot_remove_device(void *context)
98 {
99         struct acpi_device *device;
100         acpi_handle handle = context;
101         struct acpi_object_list arg_list;
102         union acpi_object arg;
103         acpi_status status = AE_OK;
104
105         if (acpi_bus_get_device(handle, &device))
106                 return 0;
107
108         if (!device)
109                 return 0;
110
111         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
112                 "Hot-removing device %s...\n", device->dev.bus_id));
113
114
115         if (acpi_bus_trim(device, 1)) {
116                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
117                                 "Removing device failed\n"));
118                 return -1;
119         }
120
121         /* power off device */
122         status = acpi_evaluate_object(handle, "_PS3", NULL, NULL);
123         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
124                 ACPI_DEBUG_PRINT((ACPI_DB_WARN,
125                                 "Power-off device failed\n"));
126
127         if (device->flags.lockable) {
128                 arg_list.count = 1;
129                 arg_list.pointer = &arg;
130                 arg.type = ACPI_TYPE_INTEGER;
131                 arg.integer.value = 0;
132                 acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
133         }
134
135         arg_list.count = 1;
136         arg_list.pointer = &arg;
137         arg.type = ACPI_TYPE_INTEGER;
138         arg.integer.value = 1;
139
140         /*
141          * TBD: _EJD support.
142          */
143         status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
144         if (ACPI_FAILURE(status))
145                 return -ENODEV;
146
147         return 0;
148 }
149
150 static ssize_t
151 acpi_eject_store(struct device *d, struct device_attribute *attr,
152                 const char *buf, size_t count)
153 {
154         int ret = count;
155         acpi_status status;
156         acpi_object_type type = 0;
157         struct acpi_device *acpi_device = to_acpi_device(d);
158         struct task_struct *task;
159
160         if ((!count) || (buf[0] != '1')) {
161                 return -EINVAL;
162         }
163 #ifndef FORCE_EJECT
164         if (acpi_device->driver == NULL) {
165                 ret = -ENODEV;
166                 goto err;
167         }
168 #endif
169         status = acpi_get_type(acpi_device->handle, &type);
170         if (ACPI_FAILURE(status) || (!acpi_device->flags.ejectable)) {
171                 ret = -ENODEV;
172                 goto err;
173         }
174
175         /* remove the device in another thread to fix the deadlock issue */
176         task = kthread_run(acpi_bus_hot_remove_device,
177                                 acpi_device->handle, "acpi_hot_remove_device");
178         if (IS_ERR(task))
179                 ret = PTR_ERR(task);
180 err:
181         return ret;
182 }
183
184 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
185
186 static ssize_t
187 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
188         struct acpi_device *acpi_dev = to_acpi_device(dev);
189
190         return sprintf(buf, "%s\n", acpi_dev->pnp.hardware_id);
191 }
192 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
193
194 static ssize_t
195 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
196         struct acpi_device *acpi_dev = to_acpi_device(dev);
197         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
198         int result;
199
200         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
201         if(result)
202                 goto end;
203
204         result = sprintf(buf, "%s\n", (char*)path.pointer);
205         kfree(path.pointer);
206   end:
207         return result;
208 }
209 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
210
211 static int acpi_device_setup_files(struct acpi_device *dev)
212 {
213         acpi_status status;
214         acpi_handle temp;
215         int result = 0;
216
217         /*
218          * Devices gotten from FADT don't have a "path" attribute
219          */
220         if(dev->handle) {
221                 result = device_create_file(&dev->dev, &dev_attr_path);
222                 if(result)
223                         goto end;
224         }
225
226         if(dev->flags.hardware_id) {
227                 result = device_create_file(&dev->dev, &dev_attr_hid);
228                 if(result)
229                         goto end;
230         }
231
232         if (dev->flags.hardware_id || dev->flags.compatible_ids){
233                 result = device_create_file(&dev->dev, &dev_attr_modalias);
234                 if(result)
235                         goto end;
236         }
237
238         /*
239          * If device has _EJ0, 'eject' file is created that is used to trigger
240          * hot-removal function from userland.
241          */
242         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
243         if (ACPI_SUCCESS(status))
244                 result = device_create_file(&dev->dev, &dev_attr_eject);
245   end:
246         return result;
247 }
248
249 static void acpi_device_remove_files(struct acpi_device *dev)
250 {
251         acpi_status status;
252         acpi_handle temp;
253
254         /*
255          * If device has _EJ0, 'eject' file is created that is used to trigger
256          * hot-removal function from userland.
257          */
258         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
259         if (ACPI_SUCCESS(status))
260                 device_remove_file(&dev->dev, &dev_attr_eject);
261
262         if (dev->flags.hardware_id || dev->flags.compatible_ids)
263                 device_remove_file(&dev->dev, &dev_attr_modalias);
264
265         if(dev->flags.hardware_id)
266                 device_remove_file(&dev->dev, &dev_attr_hid);
267         if(dev->handle)
268                 device_remove_file(&dev->dev, &dev_attr_path);
269 }
270 /* --------------------------------------------------------------------------
271                         ACPI Bus operations
272    -------------------------------------------------------------------------- */
273
274 int acpi_match_device_ids(struct acpi_device *device,
275                           const struct acpi_device_id *ids)
276 {
277         const struct acpi_device_id *id;
278
279         if (device->flags.hardware_id) {
280                 for (id = ids; id->id[0]; id++) {
281                         if (!strcmp((char*)id->id, device->pnp.hardware_id))
282                                 return 0;
283                 }
284         }
285
286         if (device->flags.compatible_ids) {
287                 struct acpi_compatible_id_list *cid_list = device->pnp.cid_list;
288                 int i;
289
290                 for (id = ids; id->id[0]; id++) {
291                         /* compare multiple _CID entries against driver ids */
292                         for (i = 0; i < cid_list->count; i++) {
293                                 if (!strcmp((char*)id->id,
294                                             cid_list->id[i].value))
295                                         return 0;
296                         }
297                 }
298         }
299
300         return -ENOENT;
301 }
302 EXPORT_SYMBOL(acpi_match_device_ids);
303
304 static void acpi_device_release(struct device *dev)
305 {
306         struct acpi_device *acpi_dev = to_acpi_device(dev);
307
308         kfree(acpi_dev->pnp.cid_list);
309         kfree(acpi_dev);
310 }
311
312 static int acpi_device_suspend(struct device *dev, pm_message_t state)
313 {
314         struct acpi_device *acpi_dev = to_acpi_device(dev);
315         struct acpi_driver *acpi_drv = acpi_dev->driver;
316
317         if (acpi_drv && acpi_drv->ops.suspend)
318                 return acpi_drv->ops.suspend(acpi_dev, state);
319         return 0;
320 }
321
322 static int acpi_device_resume(struct device *dev)
323 {
324         struct acpi_device *acpi_dev = to_acpi_device(dev);
325         struct acpi_driver *acpi_drv = acpi_dev->driver;
326
327         if (acpi_drv && acpi_drv->ops.resume)
328                 return acpi_drv->ops.resume(acpi_dev);
329         return 0;
330 }
331
332 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
333 {
334         struct acpi_device *acpi_dev = to_acpi_device(dev);
335         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
336
337         return !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
338 }
339
340 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
341 {
342         struct acpi_device *acpi_dev = to_acpi_device(dev);
343         int len;
344
345         if (add_uevent_var(env, "MODALIAS="))
346                 return -ENOMEM;
347         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
348                               sizeof(env->buf) - env->buflen);
349         if (len >= (sizeof(env->buf) - env->buflen))
350                 return -ENOMEM;
351         env->buflen += len;
352         return 0;
353 }
354
355 static int acpi_bus_driver_init(struct acpi_device *, struct acpi_driver *);
356 static int acpi_start_single_object(struct acpi_device *);
357 static int acpi_device_probe(struct device * dev)
358 {
359         struct acpi_device *acpi_dev = to_acpi_device(dev);
360         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
361         int ret;
362
363         ret = acpi_bus_driver_init(acpi_dev, acpi_drv);
364         if (!ret) {
365                 if (acpi_dev->bus_ops.acpi_op_start)
366                         acpi_start_single_object(acpi_dev);
367                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
368                         "Found driver [%s] for device [%s]\n",
369                         acpi_drv->name, acpi_dev->pnp.bus_id));
370                 get_device(dev);
371         }
372         return ret;
373 }
374
375 static int acpi_device_remove(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) {
381                 if (acpi_drv->ops.stop)
382                         acpi_drv->ops.stop(acpi_dev, acpi_dev->removal_type);
383                 if (acpi_drv->ops.remove)
384                         acpi_drv->ops.remove(acpi_dev, acpi_dev->removal_type);
385         }
386         acpi_dev->driver = NULL;
387         acpi_driver_data(dev) = NULL;
388
389         put_device(dev);
390         return 0;
391 }
392
393 static void acpi_device_shutdown(struct device *dev)
394 {
395         struct acpi_device *acpi_dev = to_acpi_device(dev);
396         struct acpi_driver *acpi_drv = acpi_dev->driver;
397
398         if (acpi_drv && acpi_drv->ops.shutdown)
399                 acpi_drv->ops.shutdown(acpi_dev);
400
401         return ;
402 }
403
404 struct bus_type acpi_bus_type = {
405         .name           = "acpi",
406         .suspend        = acpi_device_suspend,
407         .resume         = acpi_device_resume,
408         .shutdown       = acpi_device_shutdown,
409         .match          = acpi_bus_match,
410         .probe          = acpi_device_probe,
411         .remove         = acpi_device_remove,
412         .uevent         = acpi_device_uevent,
413 };
414
415 static int acpi_device_register(struct acpi_device *device,
416                                  struct acpi_device *parent)
417 {
418         int result;
419         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
420         int found = 0;
421         /*
422          * Linkage
423          * -------
424          * Link this device to its parent and siblings.
425          */
426         INIT_LIST_HEAD(&device->children);
427         INIT_LIST_HEAD(&device->node);
428         INIT_LIST_HEAD(&device->g_list);
429         INIT_LIST_HEAD(&device->wakeup_list);
430
431         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
432         if (!new_bus_id) {
433                 printk(KERN_ERR PREFIX "Memory allocation error\n");
434                 return -ENOMEM;
435         }
436
437         spin_lock(&acpi_device_lock);
438         /*
439          * Find suitable bus_id and instance number in acpi_bus_id_list
440          * If failed, create one and link it into acpi_bus_id_list
441          */
442         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
443                 if(!strcmp(acpi_device_bus_id->bus_id, device->flags.hardware_id? device->pnp.hardware_id : "device")) {
444                         acpi_device_bus_id->instance_no ++;
445                         found = 1;
446                         kfree(new_bus_id);
447                         break;
448                 }
449         }
450         if(!found) {
451                 acpi_device_bus_id = new_bus_id;
452                 strcpy(acpi_device_bus_id->bus_id, device->flags.hardware_id ? device->pnp.hardware_id : "device");
453                 acpi_device_bus_id->instance_no = 0;
454                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
455         }
456         sprintf(device->dev.bus_id, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
457
458         if (device->parent) {
459                 list_add_tail(&device->node, &device->parent->children);
460                 list_add_tail(&device->g_list, &device->parent->g_list);
461         } else
462                 list_add_tail(&device->g_list, &acpi_device_list);
463         if (device->wakeup.flags.valid)
464                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
465         spin_unlock(&acpi_device_lock);
466
467         if (device->parent)
468                 device->dev.parent = &parent->dev;
469         device->dev.bus = &acpi_bus_type;
470         device_initialize(&device->dev);
471         device->dev.release = &acpi_device_release;
472         result = device_add(&device->dev);
473         if(result) {
474                 dev_err(&device->dev, "Error adding device\n");
475                 goto end;
476         }
477
478         result = acpi_device_setup_files(device);
479         if(result)
480                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error creating sysfs interface for device %s\n", device->dev.bus_id));
481
482         device->removal_type = ACPI_BUS_REMOVAL_NORMAL;
483         return 0;
484   end:
485         spin_lock(&acpi_device_lock);
486         if (device->parent) {
487                 list_del(&device->node);
488                 list_del(&device->g_list);
489         } else
490                 list_del(&device->g_list);
491         list_del(&device->wakeup_list);
492         spin_unlock(&acpi_device_lock);
493         return result;
494 }
495
496 static void acpi_device_unregister(struct acpi_device *device, int type)
497 {
498         spin_lock(&acpi_device_lock);
499         if (device->parent) {
500                 list_del(&device->node);
501                 list_del(&device->g_list);
502         } else
503                 list_del(&device->g_list);
504
505         list_del(&device->wakeup_list);
506         spin_unlock(&acpi_device_lock);
507
508         acpi_detach_data(device->handle, acpi_bus_data_handler);
509
510         acpi_device_remove_files(device);
511         device_unregister(&device->dev);
512 }
513
514 /* --------------------------------------------------------------------------
515                                  Driver Management
516    -------------------------------------------------------------------------- */
517 /**
518  * acpi_bus_driver_init - add a device to a driver
519  * @device: the device to add and initialize
520  * @driver: driver for the device
521  *
522  * Used to initialize a device via its device driver.  Called whenever a 
523  * driver is bound to a device.  Invokes the driver's add() ops.
524  */
525 static int
526 acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
527 {
528         int result = 0;
529
530
531         if (!device || !driver)
532                 return -EINVAL;
533
534         if (!driver->ops.add)
535                 return -ENOSYS;
536
537         result = driver->ops.add(device);
538         if (result) {
539                 device->driver = NULL;
540                 acpi_driver_data(device) = NULL;
541                 return result;
542         }
543
544         device->driver = driver;
545
546         /*
547          * TBD - Configuration Management: Assign resources to device based
548          * upon possible configuration and currently allocated resources.
549          */
550
551         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
552                           "Driver successfully bound to device\n"));
553         return 0;
554 }
555
556 static int acpi_start_single_object(struct acpi_device *device)
557 {
558         int result = 0;
559         struct acpi_driver *driver;
560
561
562         if (!(driver = device->driver))
563                 return 0;
564
565         if (driver->ops.start) {
566                 result = driver->ops.start(device);
567                 if (result && driver->ops.remove)
568                         driver->ops.remove(device, ACPI_BUS_REMOVAL_NORMAL);
569         }
570
571         return result;
572 }
573
574 /**
575  * acpi_bus_register_driver - register a driver with the ACPI bus
576  * @driver: driver being registered
577  *
578  * Registers a driver with the ACPI bus.  Searches the namespace for all
579  * devices that match the driver's criteria and binds.  Returns zero for
580  * success or a negative error status for failure.
581  */
582 int acpi_bus_register_driver(struct acpi_driver *driver)
583 {
584         int ret;
585
586         if (acpi_disabled)
587                 return -ENODEV;
588         driver->drv.name = driver->name;
589         driver->drv.bus = &acpi_bus_type;
590         driver->drv.owner = driver->owner;
591
592         ret = driver_register(&driver->drv);
593         return ret;
594 }
595
596 EXPORT_SYMBOL(acpi_bus_register_driver);
597
598 /**
599  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
600  * @driver: driver to unregister
601  *
602  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
603  * devices that match the driver's criteria and unbinds.
604  */
605 void acpi_bus_unregister_driver(struct acpi_driver *driver)
606 {
607         driver_unregister(&driver->drv);
608 }
609
610 EXPORT_SYMBOL(acpi_bus_unregister_driver);
611
612 /* --------------------------------------------------------------------------
613                                  Device Enumeration
614    -------------------------------------------------------------------------- */
615 acpi_status
616 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
617 {
618         acpi_status status;
619         acpi_handle tmp;
620         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
621         union acpi_object *obj;
622
623         status = acpi_get_handle(handle, "_EJD", &tmp);
624         if (ACPI_FAILURE(status))
625                 return status;
626
627         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
628         if (ACPI_SUCCESS(status)) {
629                 obj = buffer.pointer;
630                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
631                                          ejd);
632                 kfree(buffer.pointer);
633         }
634         return status;
635 }
636 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
637
638 void acpi_bus_data_handler(acpi_handle handle, u32 function, void *context)
639 {
640
641         /* TBD */
642
643         return;
644 }
645
646 static int acpi_bus_get_perf_flags(struct acpi_device *device)
647 {
648         device->performance.state = ACPI_STATE_UNKNOWN;
649         return 0;
650 }
651
652 static acpi_status
653 acpi_bus_extract_wakeup_device_power_package(struct acpi_device *device,
654                                              union acpi_object *package)
655 {
656         int i = 0;
657         union acpi_object *element = NULL;
658
659         if (!device || !package || (package->package.count < 2))
660                 return AE_BAD_PARAMETER;
661
662         element = &(package->package.elements[0]);
663         if (!element)
664                 return AE_BAD_PARAMETER;
665         if (element->type == ACPI_TYPE_PACKAGE) {
666                 if ((element->package.count < 2) ||
667                     (element->package.elements[0].type !=
668                      ACPI_TYPE_LOCAL_REFERENCE)
669                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
670                         return AE_BAD_DATA;
671                 device->wakeup.gpe_device =
672                     element->package.elements[0].reference.handle;
673                 device->wakeup.gpe_number =
674                     (u32) element->package.elements[1].integer.value;
675         } else if (element->type == ACPI_TYPE_INTEGER) {
676                 device->wakeup.gpe_number = element->integer.value;
677         } else
678                 return AE_BAD_DATA;
679
680         element = &(package->package.elements[1]);
681         if (element->type != ACPI_TYPE_INTEGER) {
682                 return AE_BAD_DATA;
683         }
684         device->wakeup.sleep_state = element->integer.value;
685
686         if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
687                 return AE_NO_MEMORY;
688         }
689         device->wakeup.resources.count = package->package.count - 2;
690         for (i = 0; i < device->wakeup.resources.count; i++) {
691                 element = &(package->package.elements[i + 2]);
692                 if (element->type != ACPI_TYPE_LOCAL_REFERENCE)
693                         return AE_BAD_DATA;
694
695                 device->wakeup.resources.handles[i] = element->reference.handle;
696         }
697
698         return AE_OK;
699 }
700
701 static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
702 {
703         acpi_status status = 0;
704         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
705         union acpi_object *package = NULL;
706         int psw_error;
707
708         struct acpi_device_id button_device_ids[] = {
709                 {"PNP0C0D", 0},
710                 {"PNP0C0C", 0},
711                 {"PNP0C0E", 0},
712                 {"", 0},
713         };
714
715         /* _PRW */
716         status = acpi_evaluate_object(device->handle, "_PRW", NULL, &buffer);
717         if (ACPI_FAILURE(status)) {
718                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
719                 goto end;
720         }
721
722         package = (union acpi_object *)buffer.pointer;
723         status = acpi_bus_extract_wakeup_device_power_package(device, package);
724         if (ACPI_FAILURE(status)) {
725                 ACPI_EXCEPTION((AE_INFO, status, "Extracting _PRW package"));
726                 goto end;
727         }
728
729         kfree(buffer.pointer);
730
731         device->wakeup.flags.valid = 1;
732         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
733          * system for the ACPI device with the _PRW object.
734          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
735          * So it is necessary to call _DSW object first. Only when it is not
736          * present will the _PSW object used.
737          */
738         psw_error = acpi_device_sleep_wake(device, 0, 0, 0);
739         if (psw_error)
740                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
741                                 "error in _DSW or _PSW evaluation\n"));
742
743         /* Power button, Lid switch always enable wakeup */
744         if (!acpi_match_device_ids(device, button_device_ids))
745                 device->wakeup.flags.run_wake = 1;
746
747       end:
748         if (ACPI_FAILURE(status))
749                 device->flags.wake_capable = 0;
750         return 0;
751 }
752
753 static int acpi_bus_get_power_flags(struct acpi_device *device)
754 {
755         acpi_status status = 0;
756         acpi_handle handle = NULL;
757         u32 i = 0;
758
759
760         /*
761          * Power Management Flags
762          */
763         status = acpi_get_handle(device->handle, "_PSC", &handle);
764         if (ACPI_SUCCESS(status))
765                 device->power.flags.explicit_get = 1;
766         status = acpi_get_handle(device->handle, "_IRC", &handle);
767         if (ACPI_SUCCESS(status))
768                 device->power.flags.inrush_current = 1;
769
770         /*
771          * Enumerate supported power management states
772          */
773         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
774                 struct acpi_device_power_state *ps = &device->power.states[i];
775                 char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
776
777                 /* Evaluate "_PRx" to se if power resources are referenced */
778                 acpi_evaluate_reference(device->handle, object_name, NULL,
779                                         &ps->resources);
780                 if (ps->resources.count) {
781                         device->power.flags.power_resources = 1;
782                         ps->flags.valid = 1;
783                 }
784
785                 /* Evaluate "_PSx" to see if we can do explicit sets */
786                 object_name[2] = 'S';
787                 status = acpi_get_handle(device->handle, object_name, &handle);
788                 if (ACPI_SUCCESS(status)) {
789                         ps->flags.explicit_set = 1;
790                         ps->flags.valid = 1;
791                 }
792
793                 /* State is valid if we have some power control */
794                 if (ps->resources.count || ps->flags.explicit_set)
795                         ps->flags.valid = 1;
796
797                 ps->power = -1; /* Unknown - driver assigned */
798                 ps->latency = -1;       /* Unknown - driver assigned */
799         }
800
801         /* Set defaults for D0 and D3 states (always valid) */
802         device->power.states[ACPI_STATE_D0].flags.valid = 1;
803         device->power.states[ACPI_STATE_D0].power = 100;
804         device->power.states[ACPI_STATE_D3].flags.valid = 1;
805         device->power.states[ACPI_STATE_D3].power = 0;
806
807         /* TBD: System wake support and resource requirements. */
808
809         device->power.state = ACPI_STATE_UNKNOWN;
810
811         return 0;
812 }
813
814 static int acpi_bus_get_flags(struct acpi_device *device)
815 {
816         acpi_status status = AE_OK;
817         acpi_handle temp = NULL;
818
819
820         /* Presence of _STA indicates 'dynamic_status' */
821         status = acpi_get_handle(device->handle, "_STA", &temp);
822         if (ACPI_SUCCESS(status))
823                 device->flags.dynamic_status = 1;
824
825         /* Presence of _CID indicates 'compatible_ids' */
826         status = acpi_get_handle(device->handle, "_CID", &temp);
827         if (ACPI_SUCCESS(status))
828                 device->flags.compatible_ids = 1;
829
830         /* Presence of _RMV indicates 'removable' */
831         status = acpi_get_handle(device->handle, "_RMV", &temp);
832         if (ACPI_SUCCESS(status))
833                 device->flags.removable = 1;
834
835         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
836         status = acpi_get_handle(device->handle, "_EJD", &temp);
837         if (ACPI_SUCCESS(status))
838                 device->flags.ejectable = 1;
839         else {
840                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
841                 if (ACPI_SUCCESS(status))
842                         device->flags.ejectable = 1;
843         }
844
845         /* Presence of _LCK indicates 'lockable' */
846         status = acpi_get_handle(device->handle, "_LCK", &temp);
847         if (ACPI_SUCCESS(status))
848                 device->flags.lockable = 1;
849
850         /* Presence of _PS0|_PR0 indicates 'power manageable' */
851         status = acpi_get_handle(device->handle, "_PS0", &temp);
852         if (ACPI_FAILURE(status))
853                 status = acpi_get_handle(device->handle, "_PR0", &temp);
854         if (ACPI_SUCCESS(status))
855                 device->flags.power_manageable = 1;
856
857         /* Presence of _PRW indicates wake capable */
858         status = acpi_get_handle(device->handle, "_PRW", &temp);
859         if (ACPI_SUCCESS(status))
860                 device->flags.wake_capable = 1;
861
862         /* TBD: Performance management */
863
864         return 0;
865 }
866
867 static void acpi_device_get_busid(struct acpi_device *device,
868                                   acpi_handle handle, int type)
869 {
870         char bus_id[5] = { '?', 0 };
871         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
872         int i = 0;
873
874         /*
875          * Bus ID
876          * ------
877          * The device's Bus ID is simply the object name.
878          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
879          */
880         switch (type) {
881         case ACPI_BUS_TYPE_SYSTEM:
882                 strcpy(device->pnp.bus_id, "ACPI");
883                 break;
884         case ACPI_BUS_TYPE_POWER_BUTTON:
885                 strcpy(device->pnp.bus_id, "PWRF");
886                 break;
887         case ACPI_BUS_TYPE_SLEEP_BUTTON:
888                 strcpy(device->pnp.bus_id, "SLPF");
889                 break;
890         default:
891                 acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
892                 /* Clean up trailing underscores (if any) */
893                 for (i = 3; i > 1; i--) {
894                         if (bus_id[i] == '_')
895                                 bus_id[i] = '\0';
896                         else
897                                 break;
898                 }
899                 strcpy(device->pnp.bus_id, bus_id);
900                 break;
901         }
902 }
903
904 static int
905 acpi_video_bus_match(struct acpi_device *device)
906 {
907         acpi_handle h_dummy;
908
909         if (!device)
910                 return -EINVAL;
911
912         /* Since there is no HID, CID for ACPI Video drivers, we have
913          * to check well known required nodes for each feature we support.
914          */
915
916         /* Does this device able to support video switching ? */
917         if (ACPI_SUCCESS(acpi_get_handle(device->handle, "_DOD", &h_dummy)) &&
918             ACPI_SUCCESS(acpi_get_handle(device->handle, "_DOS", &h_dummy)))
919                 return 0;
920
921         /* Does this device able to retrieve a video ROM ? */
922         if (ACPI_SUCCESS(acpi_get_handle(device->handle, "_ROM", &h_dummy)))
923                 return 0;
924
925         /* Does this device able to configure which video head to be POSTed ? */
926         if (ACPI_SUCCESS(acpi_get_handle(device->handle, "_VPO", &h_dummy)) &&
927             ACPI_SUCCESS(acpi_get_handle(device->handle, "_GPD", &h_dummy)) &&
928             ACPI_SUCCESS(acpi_get_handle(device->handle, "_SPD", &h_dummy)))
929                 return 0;
930
931         return -ENODEV;
932 }
933
934 /*
935  * acpi_bay_match - see if a device is an ejectable driver bay
936  *
937  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
938  * then we can safely call it an ejectable drive bay
939  */
940 static int acpi_bay_match(struct acpi_device *device){
941         acpi_status status;
942         acpi_handle handle;
943         acpi_handle tmp;
944         acpi_handle phandle;
945
946         handle = device->handle;
947
948         status = acpi_get_handle(handle, "_EJ0", &tmp);
949         if (ACPI_FAILURE(status))
950                 return -ENODEV;
951
952         if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
953                 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
954                 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
955                 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
956                 return 0;
957
958         if (acpi_get_parent(handle, &phandle))
959                 return -ENODEV;
960
961         if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
962                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
963                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
964                 (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
965                 return 0;
966
967         return -ENODEV;
968 }
969
970 /*
971  * acpi_dock_match - see if a device has a _DCK method
972  */
973 static int acpi_dock_match(struct acpi_device *device)
974 {
975         acpi_handle tmp;
976         return acpi_get_handle(device->handle, "_DCK", &tmp);
977 }
978
979 static void acpi_device_set_id(struct acpi_device *device,
980                                struct acpi_device *parent, acpi_handle handle,
981                                int type)
982 {
983         struct acpi_device_info *info;
984         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
985         char *hid = NULL;
986         char *uid = NULL;
987         struct acpi_compatible_id_list *cid_list = NULL;
988         const char *cid_add = NULL;
989         acpi_status status;
990
991         switch (type) {
992         case ACPI_BUS_TYPE_DEVICE:
993                 status = acpi_get_object_info(handle, &buffer);
994                 if (ACPI_FAILURE(status)) {
995                         printk(KERN_ERR PREFIX "%s: Error reading device info\n", __func__);
996                         return;
997                 }
998
999                 info = buffer.pointer;
1000                 if (info->valid & ACPI_VALID_HID)
1001                         hid = info->hardware_id.value;
1002                 if (info->valid & ACPI_VALID_UID)
1003                         uid = info->unique_id.value;
1004                 if (info->valid & ACPI_VALID_CID)
1005                         cid_list = &info->compatibility_id;
1006                 if (info->valid & ACPI_VALID_ADR) {
1007                         device->pnp.bus_address = info->address;
1008                         device->flags.bus_address = 1;
1009                 }
1010
1011                 /* If we have a video/bay/dock device, add our selfdefined
1012                    HID to the CID list. Like that the video/bay/dock drivers
1013                    will get autoloaded and the device might still match
1014                    against another driver.
1015                 */
1016                 if (ACPI_SUCCESS(acpi_video_bus_match(device)))
1017                         cid_add = ACPI_VIDEO_HID;
1018                 else if (ACPI_SUCCESS(acpi_bay_match(device)))
1019                         cid_add = ACPI_BAY_HID;
1020                 else if (ACPI_SUCCESS(acpi_dock_match(device)))
1021                         cid_add = ACPI_DOCK_HID;
1022
1023                 break;
1024         case ACPI_BUS_TYPE_POWER:
1025                 hid = ACPI_POWER_HID;
1026                 break;
1027         case ACPI_BUS_TYPE_PROCESSOR:
1028                 hid = ACPI_PROCESSOR_HID;
1029                 break;
1030         case ACPI_BUS_TYPE_SYSTEM:
1031                 hid = ACPI_SYSTEM_HID;
1032                 break;
1033         case ACPI_BUS_TYPE_THERMAL:
1034                 hid = ACPI_THERMAL_HID;
1035                 break;
1036         case ACPI_BUS_TYPE_POWER_BUTTON:
1037                 hid = ACPI_BUTTON_HID_POWERF;
1038                 break;
1039         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1040                 hid = ACPI_BUTTON_HID_SLEEPF;
1041                 break;
1042         }
1043
1044         /* 
1045          * \_SB
1046          * ----
1047          * Fix for the system root bus device -- the only root-level device.
1048          */
1049         if (((acpi_handle)parent == ACPI_ROOT_OBJECT) && (type == ACPI_BUS_TYPE_DEVICE)) {
1050                 hid = ACPI_BUS_HID;
1051                 strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
1052                 strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
1053         }
1054
1055         if (hid) {
1056                 strcpy(device->pnp.hardware_id, hid);
1057                 device->flags.hardware_id = 1;
1058         }
1059         if (uid) {
1060                 strcpy(device->pnp.unique_id, uid);
1061                 device->flags.unique_id = 1;
1062         }
1063         if (cid_list || cid_add) {
1064                 struct  acpi_compatible_id_list *list;
1065                 int size = 0;
1066                 int count = 0;
1067
1068                 if (cid_list) {
1069                         size = cid_list->size;
1070                 } else if (cid_add) {
1071                         size = sizeof(struct acpi_compatible_id_list);
1072                         cid_list = ACPI_ALLOCATE_ZEROED((acpi_size) size);
1073                         if (!cid_list) {
1074                                 printk(KERN_ERR "Memory allocation error\n");
1075                                 kfree(buffer.pointer);
1076                                 return;
1077                         } else {
1078                                 cid_list->count = 0;
1079                                 cid_list->size = size;
1080                         }
1081                 }
1082                 if (cid_add)
1083                         size += sizeof(struct acpi_compatible_id);
1084                 list = kmalloc(size, GFP_KERNEL);
1085
1086                 if (list) {
1087                         if (cid_list) {
1088                                 memcpy(list, cid_list, cid_list->size);
1089                                 count = cid_list->count;
1090                         }
1091                         if (cid_add) {
1092                                 strncpy(list->id[count].value, cid_add,
1093                                         ACPI_MAX_CID_LENGTH);
1094                                 count++;
1095                                 device->flags.compatible_ids = 1;
1096                         }
1097                         list->size = size;
1098                         list->count = count;
1099                         device->pnp.cid_list = list;
1100                 } else
1101                         printk(KERN_ERR PREFIX "Memory allocation error\n");
1102         }
1103
1104         kfree(buffer.pointer);
1105 }
1106
1107 static int acpi_device_set_context(struct acpi_device *device, int type)
1108 {
1109         acpi_status status = AE_OK;
1110         int result = 0;
1111         /*
1112          * Context
1113          * -------
1114          * Attach this 'struct acpi_device' to the ACPI object.  This makes
1115          * resolutions from handle->device very efficient.  Note that we need
1116          * to be careful with fixed-feature devices as they all attach to the
1117          * root object.
1118          */
1119         if (type != ACPI_BUS_TYPE_POWER_BUTTON &&
1120             type != ACPI_BUS_TYPE_SLEEP_BUTTON) {
1121                 status = acpi_attach_data(device->handle,
1122                                           acpi_bus_data_handler, device);
1123
1124                 if (ACPI_FAILURE(status)) {
1125                         printk(KERN_ERR PREFIX "Error attaching device data\n");
1126                         result = -ENODEV;
1127                 }
1128         }
1129         return result;
1130 }
1131
1132 static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
1133 {
1134         if (!dev)
1135                 return -EINVAL;
1136
1137         dev->removal_type = ACPI_BUS_REMOVAL_EJECT;
1138         device_release_driver(&dev->dev);
1139
1140         if (!rmdevice)
1141                 return 0;
1142
1143         /*
1144          * unbind _ADR-Based Devices when hot removal
1145          */
1146         if (dev->flags.bus_address) {
1147                 if ((dev->parent) && (dev->parent->ops.unbind))
1148                         dev->parent->ops.unbind(dev);
1149         }
1150         acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
1151
1152         return 0;
1153 }
1154
1155 static int
1156 acpi_is_child_device(struct acpi_device *device,
1157                         int (*matcher)(struct acpi_device *))
1158 {
1159         int result = -ENODEV;
1160
1161         do {
1162                 if (ACPI_SUCCESS(matcher(device)))
1163                         return AE_OK;
1164         } while ((device = device->parent));
1165
1166         return result;
1167 }
1168
1169 static int
1170 acpi_add_single_object(struct acpi_device **child,
1171                        struct acpi_device *parent, acpi_handle handle, int type,
1172                         struct acpi_bus_ops *ops)
1173 {
1174         int result = 0;
1175         struct acpi_device *device = NULL;
1176
1177
1178         if (!child)
1179                 return -EINVAL;
1180
1181         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1182         if (!device) {
1183                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1184                 return -ENOMEM;
1185         }
1186
1187         device->handle = handle;
1188         device->parent = parent;
1189         device->bus_ops = *ops; /* workround for not call .start */
1190
1191
1192         acpi_device_get_busid(device, handle, type);
1193
1194         /*
1195          * Flags
1196          * -----
1197          * Get prior to calling acpi_bus_get_status() so we know whether
1198          * or not _STA is present.  Note that we only look for object
1199          * handles -- cannot evaluate objects until we know the device is
1200          * present and properly initialized.
1201          */
1202         result = acpi_bus_get_flags(device);
1203         if (result)
1204                 goto end;
1205
1206         /*
1207          * Status
1208          * ------
1209          * See if the device is present.  We always assume that non-Device
1210          * and non-Processor objects (e.g. thermal zones, power resources,
1211          * etc.) are present, functioning, etc. (at least when parent object
1212          * is present).  Note that _STA has a different meaning for some
1213          * objects (e.g. power resources) so we need to be careful how we use
1214          * it.
1215          */
1216         switch (type) {
1217         case ACPI_BUS_TYPE_PROCESSOR:
1218         case ACPI_BUS_TYPE_DEVICE:
1219                 result = acpi_bus_get_status(device);
1220                 if (ACPI_FAILURE(result)) {
1221                         result = -ENODEV;
1222                         goto end;
1223                 }
1224                 if (!device->status.present) {
1225                         /* Bay and dock should be handled even if absent */
1226                         if (!ACPI_SUCCESS(
1227                              acpi_is_child_device(device, acpi_bay_match)) &&
1228                             !ACPI_SUCCESS(
1229                              acpi_is_child_device(device, acpi_dock_match))) {
1230                                         result = -ENODEV;
1231                                         goto end;
1232                         }
1233                 }
1234                 break;
1235         default:
1236                 STRUCT_TO_INT(device->status) =
1237                     ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED |
1238                     ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING;
1239                 break;
1240         }
1241
1242         /*
1243          * Initialize Device
1244          * -----------------
1245          * TBD: Synch with Core's enumeration/initialization process.
1246          */
1247
1248         /*
1249          * Hardware ID, Unique ID, & Bus Address
1250          * -------------------------------------
1251          */
1252         acpi_device_set_id(device, parent, handle, type);
1253
1254         /*
1255          * Power Management
1256          * ----------------
1257          */
1258         if (device->flags.power_manageable) {
1259                 result = acpi_bus_get_power_flags(device);
1260                 if (result)
1261                         goto end;
1262         }
1263
1264         /*
1265          * Wakeup device management
1266          *-----------------------
1267          */
1268         if (device->flags.wake_capable) {
1269                 result = acpi_bus_get_wakeup_device_flags(device);
1270                 if (result)
1271                         goto end;
1272         }
1273
1274         /*
1275          * Performance Management
1276          * ----------------------
1277          */
1278         if (device->flags.performance_manageable) {
1279                 result = acpi_bus_get_perf_flags(device);
1280                 if (result)
1281                         goto end;
1282         }
1283
1284         if ((result = acpi_device_set_context(device, type)))
1285                 goto end;
1286
1287         result = acpi_device_register(device, parent);
1288
1289         /*
1290          * Bind _ADR-Based Devices when hot add
1291          */
1292         if (device->flags.bus_address) {
1293                 if (device->parent && device->parent->ops.bind)
1294                         device->parent->ops.bind(device);
1295         }
1296
1297       end:
1298         if (!result)
1299                 *child = device;
1300         else {
1301                 kfree(device->pnp.cid_list);
1302                 kfree(device);
1303         }
1304
1305         return result;
1306 }
1307
1308 static int acpi_bus_scan(struct acpi_device *start, struct acpi_bus_ops *ops)
1309 {
1310         acpi_status status = AE_OK;
1311         struct acpi_device *parent = NULL;
1312         struct acpi_device *child = NULL;
1313         acpi_handle phandle = NULL;
1314         acpi_handle chandle = NULL;
1315         acpi_object_type type = 0;
1316         u32 level = 1;
1317
1318
1319         if (!start)
1320                 return -EINVAL;
1321
1322         parent = start;
1323         phandle = start->handle;
1324
1325         /*
1326          * Parse through the ACPI namespace, identify all 'devices', and
1327          * create a new 'struct acpi_device' for each.
1328          */
1329         while ((level > 0) && parent) {
1330
1331                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1332                                               chandle, &chandle);
1333
1334                 /*
1335                  * If this scope is exhausted then move our way back up.
1336                  */
1337                 if (ACPI_FAILURE(status)) {
1338                         level--;
1339                         chandle = phandle;
1340                         acpi_get_parent(phandle, &phandle);
1341                         if (parent->parent)
1342                                 parent = parent->parent;
1343                         continue;
1344                 }
1345
1346                 status = acpi_get_type(chandle, &type);
1347                 if (ACPI_FAILURE(status))
1348                         continue;
1349
1350                 /*
1351                  * If this is a scope object then parse it (depth-first).
1352                  */
1353                 if (type == ACPI_TYPE_LOCAL_SCOPE) {
1354                         level++;
1355                         phandle = chandle;
1356                         chandle = NULL;
1357                         continue;
1358                 }
1359
1360                 /*
1361                  * We're only interested in objects that we consider 'devices'.
1362                  */
1363                 switch (type) {
1364                 case ACPI_TYPE_DEVICE:
1365                         type = ACPI_BUS_TYPE_DEVICE;
1366                         break;
1367                 case ACPI_TYPE_PROCESSOR:
1368                         type = ACPI_BUS_TYPE_PROCESSOR;
1369                         break;
1370                 case ACPI_TYPE_THERMAL:
1371                         type = ACPI_BUS_TYPE_THERMAL;
1372                         break;
1373                 case ACPI_TYPE_POWER:
1374                         type = ACPI_BUS_TYPE_POWER;
1375                         break;
1376                 default:
1377                         continue;
1378                 }
1379
1380                 if (ops->acpi_op_add)
1381                         status = acpi_add_single_object(&child, parent,
1382                                 chandle, type, ops);
1383                 else
1384                         status = acpi_bus_get_device(chandle, &child);
1385
1386                 if (ACPI_FAILURE(status))
1387                         continue;
1388
1389                 if (ops->acpi_op_start && !(ops->acpi_op_add)) {
1390                         status = acpi_start_single_object(child);
1391                         if (ACPI_FAILURE(status))
1392                                 continue;
1393                 }
1394
1395                 /*
1396                  * If the device is present, enabled, and functioning then
1397                  * parse its scope (depth-first).  Note that we need to
1398                  * represent absent devices to facilitate PnP notifications
1399                  * -- but only the subtree head (not all of its children,
1400                  * which will be enumerated when the parent is inserted).
1401                  *
1402                  * TBD: Need notifications and other detection mechanisms
1403                  *      in place before we can fully implement this.
1404                  */
1405                 if (child->status.present) {
1406                         status = acpi_get_next_object(ACPI_TYPE_ANY, chandle,
1407                                                       NULL, NULL);
1408                         if (ACPI_SUCCESS(status)) {
1409                                 level++;
1410                                 phandle = chandle;
1411                                 chandle = NULL;
1412                                 parent = child;
1413                         }
1414                 }
1415         }
1416
1417         return 0;
1418 }
1419
1420 int
1421 acpi_bus_add(struct acpi_device **child,
1422              struct acpi_device *parent, acpi_handle handle, int type)
1423 {
1424         int result;
1425         struct acpi_bus_ops ops;
1426
1427         memset(&ops, 0, sizeof(ops));
1428         ops.acpi_op_add = 1;
1429
1430         result = acpi_add_single_object(child, parent, handle, type, &ops);
1431         if (!result)
1432                 result = acpi_bus_scan(*child, &ops);
1433
1434         return result;
1435 }
1436
1437 EXPORT_SYMBOL(acpi_bus_add);
1438
1439 int acpi_bus_start(struct acpi_device *device)
1440 {
1441         int result;
1442         struct acpi_bus_ops ops;
1443
1444
1445         if (!device)
1446                 return -EINVAL;
1447
1448         result = acpi_start_single_object(device);
1449         if (!result) {
1450                 memset(&ops, 0, sizeof(ops));
1451                 ops.acpi_op_start = 1;
1452                 result = acpi_bus_scan(device, &ops);
1453         }
1454         return result;
1455 }
1456
1457 EXPORT_SYMBOL(acpi_bus_start);
1458
1459 int acpi_bus_trim(struct acpi_device *start, int rmdevice)
1460 {
1461         acpi_status status;
1462         struct acpi_device *parent, *child;
1463         acpi_handle phandle, chandle;
1464         acpi_object_type type;
1465         u32 level = 1;
1466         int err = 0;
1467
1468         parent = start;
1469         phandle = start->handle;
1470         child = chandle = NULL;
1471
1472         while ((level > 0) && parent && (!err)) {
1473                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1474                                               chandle, &chandle);
1475
1476                 /*
1477                  * If this scope is exhausted then move our way back up.
1478                  */
1479                 if (ACPI_FAILURE(status)) {
1480                         level--;
1481                         chandle = phandle;
1482                         acpi_get_parent(phandle, &phandle);
1483                         child = parent;
1484                         parent = parent->parent;
1485
1486                         if (level == 0)
1487                                 err = acpi_bus_remove(child, rmdevice);
1488                         else
1489                                 err = acpi_bus_remove(child, 1);
1490
1491                         continue;
1492                 }
1493
1494                 status = acpi_get_type(chandle, &type);
1495                 if (ACPI_FAILURE(status)) {
1496                         continue;
1497                 }
1498                 /*
1499                  * If there is a device corresponding to chandle then
1500                  * parse it (depth-first).
1501                  */
1502                 if (acpi_bus_get_device(chandle, &child) == 0) {
1503                         level++;
1504                         phandle = chandle;
1505                         chandle = NULL;
1506                         parent = child;
1507                 }
1508                 continue;
1509         }
1510         return err;
1511 }
1512 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1513
1514
1515 static int acpi_bus_scan_fixed(struct acpi_device *root)
1516 {
1517         int result = 0;
1518         struct acpi_device *device = NULL;
1519         struct acpi_bus_ops ops;
1520
1521         if (!root)
1522                 return -ENODEV;
1523
1524         memset(&ops, 0, sizeof(ops));
1525         ops.acpi_op_add = 1;
1526         ops.acpi_op_start = 1;
1527
1528         /*
1529          * Enumerate all fixed-feature devices.
1530          */
1531         if ((acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON) == 0) {
1532                 result = acpi_add_single_object(&device, acpi_root,
1533                                                 NULL,
1534                                                 ACPI_BUS_TYPE_POWER_BUTTON,
1535                                                 &ops);
1536         }
1537
1538         if ((acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON) == 0) {
1539                 result = acpi_add_single_object(&device, acpi_root,
1540                                                 NULL,
1541                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
1542                                                 &ops);
1543         }
1544
1545         return result;
1546 }
1547
1548 int __init acpi_boot_ec_enable(void);
1549
1550 static int __init acpi_scan_init(void)
1551 {
1552         int result;
1553         struct acpi_bus_ops ops;
1554
1555
1556         if (acpi_disabled)
1557                 return 0;
1558
1559         memset(&ops, 0, sizeof(ops));
1560         ops.acpi_op_add = 1;
1561         ops.acpi_op_start = 1;
1562
1563         result = bus_register(&acpi_bus_type);
1564         if (result) {
1565                 /* We don't want to quit even if we failed to add suspend/resume */
1566                 printk(KERN_ERR PREFIX "Could not register bus type\n");
1567         }
1568
1569         /*
1570          * Create the root device in the bus's device tree
1571          */
1572         result = acpi_add_single_object(&acpi_root, NULL, ACPI_ROOT_OBJECT,
1573                                         ACPI_BUS_TYPE_SYSTEM, &ops);
1574         if (result)
1575                 goto Done;
1576
1577         /*
1578          * Enumerate devices in the ACPI namespace.
1579          */
1580         result = acpi_bus_scan_fixed(acpi_root);
1581
1582         /* EC region might be needed at bus_scan, so enable it now */
1583         acpi_boot_ec_enable();
1584
1585         if (!result)
1586                 result = acpi_bus_scan(acpi_root, &ops);
1587
1588         if (result)
1589                 acpi_device_unregister(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
1590
1591       Done:
1592         return result;
1593 }
1594
1595 subsys_initcall(acpi_scan_init);