]> git.karo-electronics.de Git - linux-beck.git/blob - drivers/acpi/scan.c
ACPI / dock: fix error return code in dock_add()
[linux-beck.git] / drivers / acpi / scan.c
1 /*
2  * scan.c - support for transforming the ACPI namespace into individual objects
3  */
4
5 #include <linux/module.h>
6 #include <linux/init.h>
7 #include <linux/slab.h>
8 #include <linux/kernel.h>
9 #include <linux/acpi.h>
10 #include <linux/signal.h>
11 #include <linux/kthread.h>
12 #include <linux/dmi.h>
13 #include <linux/nls.h>
14
15 #include <acpi/acpi_drivers.h>
16
17 #include "internal.h"
18
19 #define _COMPONENT              ACPI_BUS_COMPONENT
20 ACPI_MODULE_NAME("scan");
21 #define STRUCT_TO_INT(s)        (*((int*)&s))
22 extern struct acpi_device *acpi_root;
23
24 #define ACPI_BUS_CLASS                  "system_bus"
25 #define ACPI_BUS_HID                    "LNXSYBUS"
26 #define ACPI_BUS_DEVICE_NAME            "System Bus"
27
28 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
29
30 /*
31  * If set, devices will be hot-removed even if they cannot be put offline
32  * gracefully (from the kernel's standpoint).
33  */
34 bool acpi_force_hot_remove;
35
36 static const char *dummy_hid = "device";
37
38 static LIST_HEAD(acpi_bus_id_list);
39 static DEFINE_MUTEX(acpi_scan_lock);
40 static LIST_HEAD(acpi_scan_handlers_list);
41 DEFINE_MUTEX(acpi_device_lock);
42 LIST_HEAD(acpi_wakeup_device_list);
43
44 struct acpi_device_bus_id{
45         char bus_id[15];
46         unsigned int instance_no;
47         struct list_head node;
48 };
49
50 void acpi_scan_lock_acquire(void)
51 {
52         mutex_lock(&acpi_scan_lock);
53 }
54 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
55
56 void acpi_scan_lock_release(void)
57 {
58         mutex_unlock(&acpi_scan_lock);
59 }
60 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
61
62 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
63 {
64         if (!handler || !handler->attach)
65                 return -EINVAL;
66
67         list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
68         return 0;
69 }
70
71 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
72                                        const char *hotplug_profile_name)
73 {
74         int error;
75
76         error = acpi_scan_add_handler(handler);
77         if (error)
78                 return error;
79
80         acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
81         return 0;
82 }
83
84 /*
85  * Creates hid/cid(s) string needed for modalias and uevent
86  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
87  * char *modalias: "acpi:IBM0001:ACPI0001"
88 */
89 static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
90                            int size)
91 {
92         int len;
93         int count;
94         struct acpi_hardware_id *id;
95
96         if (list_empty(&acpi_dev->pnp.ids))
97                 return 0;
98
99         len = snprintf(modalias, size, "acpi:");
100         size -= len;
101
102         list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
103                 count = snprintf(&modalias[len], size, "%s:", id->id);
104                 if (count < 0 || count >= size)
105                         return -EINVAL;
106                 len += count;
107                 size -= count;
108         }
109
110         modalias[len] = '\0';
111         return len;
112 }
113
114 static ssize_t
115 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
116         struct acpi_device *acpi_dev = to_acpi_device(dev);
117         int len;
118
119         /* Device has no HID and no CID or string is >1024 */
120         len = create_modalias(acpi_dev, buf, 1024);
121         if (len <= 0)
122                 return 0;
123         buf[len++] = '\n';
124         return len;
125 }
126 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
127
128 static acpi_status acpi_bus_offline_companions(acpi_handle handle, u32 lvl,
129                                                void *data, void **ret_p)
130 {
131         struct acpi_device *device = NULL;
132         struct acpi_device_physical_node *pn;
133         bool second_pass = (bool)data;
134         acpi_status status = AE_OK;
135
136         if (acpi_bus_get_device(handle, &device))
137                 return AE_OK;
138
139         mutex_lock(&device->physical_node_lock);
140
141         list_for_each_entry(pn, &device->physical_node_list, node) {
142                 int ret;
143
144                 if (second_pass) {
145                         /* Skip devices offlined by the first pass. */
146                         if (pn->put_online)
147                                 continue;
148                 } else {
149                         pn->put_online = false;
150                 }
151                 ret = device_offline(pn->dev);
152                 if (acpi_force_hot_remove)
153                         continue;
154
155                 if (ret >= 0) {
156                         pn->put_online = !ret;
157                 } else {
158                         *ret_p = pn->dev;
159                         if (second_pass) {
160                                 status = AE_ERROR;
161                                 break;
162                         }
163                 }
164         }
165
166         mutex_unlock(&device->physical_node_lock);
167
168         return status;
169 }
170
171 static acpi_status acpi_bus_online_companions(acpi_handle handle, u32 lvl,
172                                               void *data, void **ret_p)
173 {
174         struct acpi_device *device = NULL;
175         struct acpi_device_physical_node *pn;
176
177         if (acpi_bus_get_device(handle, &device))
178                 return AE_OK;
179
180         mutex_lock(&device->physical_node_lock);
181
182         list_for_each_entry(pn, &device->physical_node_list, node)
183                 if (pn->put_online) {
184                         device_online(pn->dev);
185                         pn->put_online = false;
186                 }
187
188         mutex_unlock(&device->physical_node_lock);
189
190         return AE_OK;
191 }
192
193 static int acpi_scan_hot_remove(struct acpi_device *device)
194 {
195         acpi_handle handle = device->handle;
196         struct device *errdev;
197         acpi_status status;
198         unsigned long long sta;
199
200         /* If there is no handle, the device node has been unregistered. */
201         if (!handle) {
202                 dev_dbg(&device->dev, "ACPI handle missing\n");
203                 put_device(&device->dev);
204                 return -EINVAL;
205         }
206
207         lock_device_hotplug();
208
209         /*
210          * Carry out two passes here and ignore errors in the first pass,
211          * because if the devices in question are memory blocks and
212          * CONFIG_MEMCG is set, one of the blocks may hold data structures
213          * that the other blocks depend on, but it is not known in advance which
214          * block holds them.
215          *
216          * If the first pass is successful, the second one isn't needed, though.
217          */
218         errdev = NULL;
219         acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
220                             NULL, acpi_bus_offline_companions,
221                             (void *)false, (void **)&errdev);
222         acpi_bus_offline_companions(handle, 0, (void *)false, (void **)&errdev);
223         if (errdev) {
224                 errdev = NULL;
225                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
226                                     NULL, acpi_bus_offline_companions,
227                                     (void *)true , (void **)&errdev);
228                 if (!errdev || acpi_force_hot_remove)
229                         acpi_bus_offline_companions(handle, 0, (void *)true,
230                                                     (void **)&errdev);
231
232                 if (errdev && !acpi_force_hot_remove) {
233                         dev_warn(errdev, "Offline failed.\n");
234                         acpi_bus_online_companions(handle, 0, NULL, NULL);
235                         acpi_walk_namespace(ACPI_TYPE_ANY, handle,
236                                             ACPI_UINT32_MAX,
237                                             acpi_bus_online_companions, NULL,
238                                             NULL, NULL);
239
240                         unlock_device_hotplug();
241
242                         put_device(&device->dev);
243                         return -EBUSY;
244                 }
245         }
246
247         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
248                 "Hot-removing device %s...\n", dev_name(&device->dev)));
249
250         acpi_bus_trim(device);
251
252         unlock_device_hotplug();
253
254         /* Device node has been unregistered. */
255         put_device(&device->dev);
256         device = NULL;
257
258         acpi_evaluate_lck(handle, 0);
259         /*
260          * TBD: _EJD support.
261          */
262         status = acpi_evaluate_ej0(handle);
263         if (status == AE_NOT_FOUND)
264                 return -ENODEV;
265         else if (ACPI_FAILURE(status))
266                 return -EIO;
267
268         /*
269          * Verify if eject was indeed successful.  If not, log an error
270          * message.  No need to call _OST since _EJ0 call was made OK.
271          */
272         status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
273         if (ACPI_FAILURE(status)) {
274                 acpi_handle_warn(handle,
275                         "Status check after eject failed (0x%x)\n", status);
276         } else if (sta & ACPI_STA_DEVICE_ENABLED) {
277                 acpi_handle_warn(handle,
278                         "Eject incomplete - status 0x%llx\n", sta);
279         }
280
281         return 0;
282 }
283
284 static void acpi_bus_device_eject(void *context)
285 {
286         acpi_handle handle = context;
287         struct acpi_device *device = NULL;
288         struct acpi_scan_handler *handler;
289         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
290
291         mutex_lock(&acpi_scan_lock);
292
293         acpi_bus_get_device(handle, &device);
294         if (!device)
295                 goto err_out;
296
297         handler = device->handler;
298         if (!handler || !handler->hotplug.enabled) {
299                 ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
300                 goto err_out;
301         }
302         acpi_evaluate_hotplug_ost(handle, ACPI_NOTIFY_EJECT_REQUEST,
303                                   ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
304         if (handler->hotplug.mode == AHM_CONTAINER) {
305                 device->flags.eject_pending = true;
306                 kobject_uevent(&device->dev.kobj, KOBJ_OFFLINE);
307         } else {
308                 int error;
309
310                 get_device(&device->dev);
311                 error = acpi_scan_hot_remove(device);
312                 if (error)
313                         goto err_out;
314         }
315
316  out:
317         mutex_unlock(&acpi_scan_lock);
318         return;
319
320  err_out:
321         acpi_evaluate_hotplug_ost(handle, ACPI_NOTIFY_EJECT_REQUEST, ost_code,
322                                   NULL);
323         goto out;
324 }
325
326 static void acpi_scan_bus_device_check(acpi_handle handle, u32 ost_source)
327 {
328         struct acpi_device *device = NULL;
329         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
330         int error;
331
332         mutex_lock(&acpi_scan_lock);
333         lock_device_hotplug();
334
335         acpi_bus_get_device(handle, &device);
336         if (device) {
337                 dev_warn(&device->dev, "Attempt to re-insert\n");
338                 goto out;
339         }
340         acpi_evaluate_hotplug_ost(handle, ost_source,
341                                   ACPI_OST_SC_INSERT_IN_PROGRESS, NULL);
342         error = acpi_bus_scan(handle);
343         if (error) {
344                 acpi_handle_warn(handle, "Namespace scan failure\n");
345                 goto out;
346         }
347         error = acpi_bus_get_device(handle, &device);
348         if (error) {
349                 acpi_handle_warn(handle, "Missing device node object\n");
350                 goto out;
351         }
352         ost_code = ACPI_OST_SC_SUCCESS;
353         if (device->handler && device->handler->hotplug.mode == AHM_CONTAINER)
354                 kobject_uevent(&device->dev.kobj, KOBJ_ONLINE);
355
356  out:
357         unlock_device_hotplug();
358         acpi_evaluate_hotplug_ost(handle, ost_source, ost_code, NULL);
359         mutex_unlock(&acpi_scan_lock);
360 }
361
362 static void acpi_scan_bus_check(void *context)
363 {
364         acpi_scan_bus_device_check((acpi_handle)context,
365                                    ACPI_NOTIFY_BUS_CHECK);
366 }
367
368 static void acpi_scan_device_check(void *context)
369 {
370         acpi_scan_bus_device_check((acpi_handle)context,
371                                    ACPI_NOTIFY_DEVICE_CHECK);
372 }
373
374 static void acpi_hotplug_unsupported(acpi_handle handle, u32 type)
375 {
376         u32 ost_status;
377
378         switch (type) {
379         case ACPI_NOTIFY_BUS_CHECK:
380                 acpi_handle_debug(handle,
381                         "ACPI_NOTIFY_BUS_CHECK event: unsupported\n");
382                 ost_status = ACPI_OST_SC_INSERT_NOT_SUPPORTED;
383                 break;
384         case ACPI_NOTIFY_DEVICE_CHECK:
385                 acpi_handle_debug(handle,
386                         "ACPI_NOTIFY_DEVICE_CHECK event: unsupported\n");
387                 ost_status = ACPI_OST_SC_INSERT_NOT_SUPPORTED;
388                 break;
389         case ACPI_NOTIFY_EJECT_REQUEST:
390                 acpi_handle_debug(handle,
391                         "ACPI_NOTIFY_EJECT_REQUEST event: unsupported\n");
392                 ost_status = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
393                 break;
394         default:
395                 /* non-hotplug event; possibly handled by other handler */
396                 return;
397         }
398
399         acpi_evaluate_hotplug_ost(handle, type, ost_status, NULL);
400 }
401
402 static void acpi_hotplug_notify_cb(acpi_handle handle, u32 type, void *data)
403 {
404         acpi_osd_exec_callback callback;
405         struct acpi_scan_handler *handler = data;
406         acpi_status status;
407
408         if (!handler->hotplug.enabled)
409                 return acpi_hotplug_unsupported(handle, type);
410
411         switch (type) {
412         case ACPI_NOTIFY_BUS_CHECK:
413                 acpi_handle_debug(handle, "ACPI_NOTIFY_BUS_CHECK event\n");
414                 callback = acpi_scan_bus_check;
415                 break;
416         case ACPI_NOTIFY_DEVICE_CHECK:
417                 acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_CHECK event\n");
418                 callback = acpi_scan_device_check;
419                 break;
420         case ACPI_NOTIFY_EJECT_REQUEST:
421                 acpi_handle_debug(handle, "ACPI_NOTIFY_EJECT_REQUEST event\n");
422                 callback = acpi_bus_device_eject;
423                 break;
424         default:
425                 /* non-hotplug event; possibly handled by other handler */
426                 return;
427         }
428         status = acpi_os_hotplug_execute(callback, handle);
429         if (ACPI_FAILURE(status))
430                 acpi_evaluate_hotplug_ost(handle, type,
431                                           ACPI_OST_SC_NON_SPECIFIC_FAILURE,
432                                           NULL);
433 }
434
435 /**
436  * acpi_bus_hot_remove_device: hot-remove a device and its children
437  * @context: struct acpi_eject_event pointer (freed in this func)
438  *
439  * Hot-remove a device and its children. This function frees up the
440  * memory space passed by arg context, so that the caller may call
441  * this function asynchronously through acpi_os_hotplug_execute().
442  */
443 void acpi_bus_hot_remove_device(void *context)
444 {
445         struct acpi_eject_event *ej_event = context;
446         struct acpi_device *device = ej_event->device;
447         acpi_handle handle = device->handle;
448         int error;
449
450         mutex_lock(&acpi_scan_lock);
451
452         error = acpi_scan_hot_remove(device);
453         if (error && handle)
454                 acpi_evaluate_hotplug_ost(handle, ej_event->event,
455                                           ACPI_OST_SC_NON_SPECIFIC_FAILURE,
456                                           NULL);
457
458         mutex_unlock(&acpi_scan_lock);
459         kfree(context);
460 }
461 EXPORT_SYMBOL(acpi_bus_hot_remove_device);
462
463 static ssize_t real_power_state_show(struct device *dev,
464                                      struct device_attribute *attr, char *buf)
465 {
466         struct acpi_device *adev = to_acpi_device(dev);
467         int state;
468         int ret;
469
470         ret = acpi_device_get_power(adev, &state);
471         if (ret)
472                 return ret;
473
474         return sprintf(buf, "%s\n", acpi_power_state_string(state));
475 }
476
477 static DEVICE_ATTR(real_power_state, 0444, real_power_state_show, NULL);
478
479 static ssize_t power_state_show(struct device *dev,
480                                 struct device_attribute *attr, char *buf)
481 {
482         struct acpi_device *adev = to_acpi_device(dev);
483
484         return sprintf(buf, "%s\n", acpi_power_state_string(adev->power.state));
485 }
486
487 static DEVICE_ATTR(power_state, 0444, power_state_show, NULL);
488
489 static ssize_t
490 acpi_eject_store(struct device *d, struct device_attribute *attr,
491                 const char *buf, size_t count)
492 {
493         struct acpi_device *acpi_device = to_acpi_device(d);
494         struct acpi_eject_event *ej_event;
495         acpi_object_type not_used;
496         acpi_status status;
497         u32 ost_source;
498         int ret;
499
500         if (!count || buf[0] != '1')
501                 return -EINVAL;
502
503         if ((!acpi_device->handler || !acpi_device->handler->hotplug.enabled)
504             && !acpi_device->driver)
505                 return -ENODEV;
506
507         status = acpi_get_type(acpi_device->handle, &not_used);
508         if (ACPI_FAILURE(status) || !acpi_device->flags.ejectable)
509                 return -ENODEV;
510
511         mutex_lock(&acpi_scan_lock);
512
513         if (acpi_device->flags.eject_pending) {
514                 /* ACPI eject notification event. */
515                 ost_source = ACPI_NOTIFY_EJECT_REQUEST;
516                 acpi_device->flags.eject_pending = 0;
517         } else {
518                 /* Eject initiated by user space. */
519                 ost_source = ACPI_OST_EC_OSPM_EJECT;
520         }
521         ej_event = kmalloc(sizeof(*ej_event), GFP_KERNEL);
522         if (!ej_event) {
523                 ret = -ENOMEM;
524                 goto err_out;
525         }
526         acpi_evaluate_hotplug_ost(acpi_device->handle, ost_source,
527                                   ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
528         ej_event->device = acpi_device;
529         ej_event->event = ost_source;
530         get_device(&acpi_device->dev);
531         status = acpi_os_hotplug_execute(acpi_bus_hot_remove_device, ej_event);
532         if (ACPI_FAILURE(status)) {
533                 put_device(&acpi_device->dev);
534                 kfree(ej_event);
535                 ret = status == AE_NO_MEMORY ? -ENOMEM : -EAGAIN;
536                 goto err_out;
537         }
538         ret = count;
539
540  out:
541         mutex_unlock(&acpi_scan_lock);
542         return ret;
543
544  err_out:
545         acpi_evaluate_hotplug_ost(acpi_device->handle, ost_source,
546                                   ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL);
547         goto out;
548 }
549
550 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
551
552 static ssize_t
553 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
554         struct acpi_device *acpi_dev = to_acpi_device(dev);
555
556         return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
557 }
558 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
559
560 static ssize_t acpi_device_uid_show(struct device *dev,
561                                     struct device_attribute *attr, char *buf)
562 {
563         struct acpi_device *acpi_dev = to_acpi_device(dev);
564
565         return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id);
566 }
567 static DEVICE_ATTR(uid, 0444, acpi_device_uid_show, NULL);
568
569 static ssize_t acpi_device_adr_show(struct device *dev,
570                                     struct device_attribute *attr, char *buf)
571 {
572         struct acpi_device *acpi_dev = to_acpi_device(dev);
573
574         return sprintf(buf, "0x%08x\n",
575                        (unsigned int)(acpi_dev->pnp.bus_address));
576 }
577 static DEVICE_ATTR(adr, 0444, acpi_device_adr_show, NULL);
578
579 static ssize_t
580 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
581         struct acpi_device *acpi_dev = to_acpi_device(dev);
582         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
583         int result;
584
585         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
586         if (result)
587                 goto end;
588
589         result = sprintf(buf, "%s\n", (char*)path.pointer);
590         kfree(path.pointer);
591 end:
592         return result;
593 }
594 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
595
596 /* sysfs file that shows description text from the ACPI _STR method */
597 static ssize_t description_show(struct device *dev,
598                                 struct device_attribute *attr,
599                                 char *buf) {
600         struct acpi_device *acpi_dev = to_acpi_device(dev);
601         int result;
602
603         if (acpi_dev->pnp.str_obj == NULL)
604                 return 0;
605
606         /*
607          * The _STR object contains a Unicode identifier for a device.
608          * We need to convert to utf-8 so it can be displayed.
609          */
610         result = utf16s_to_utf8s(
611                 (wchar_t *)acpi_dev->pnp.str_obj->buffer.pointer,
612                 acpi_dev->pnp.str_obj->buffer.length,
613                 UTF16_LITTLE_ENDIAN, buf,
614                 PAGE_SIZE);
615
616         buf[result++] = '\n';
617
618         return result;
619 }
620 static DEVICE_ATTR(description, 0444, description_show, NULL);
621
622 static ssize_t
623 acpi_device_sun_show(struct device *dev, struct device_attribute *attr,
624                      char *buf) {
625         struct acpi_device *acpi_dev = to_acpi_device(dev);
626
627         return sprintf(buf, "%lu\n", acpi_dev->pnp.sun);
628 }
629 static DEVICE_ATTR(sun, 0444, acpi_device_sun_show, NULL);
630
631 static int acpi_device_setup_files(struct acpi_device *dev)
632 {
633         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
634         acpi_status status;
635         unsigned long long sun;
636         int result = 0;
637
638         /*
639          * Devices gotten from FADT don't have a "path" attribute
640          */
641         if (dev->handle) {
642                 result = device_create_file(&dev->dev, &dev_attr_path);
643                 if (result)
644                         goto end;
645         }
646
647         if (!list_empty(&dev->pnp.ids)) {
648                 result = device_create_file(&dev->dev, &dev_attr_hid);
649                 if (result)
650                         goto end;
651
652                 result = device_create_file(&dev->dev, &dev_attr_modalias);
653                 if (result)
654                         goto end;
655         }
656
657         /*
658          * If device has _STR, 'description' file is created
659          */
660         if (acpi_has_method(dev->handle, "_STR")) {
661                 status = acpi_evaluate_object(dev->handle, "_STR",
662                                         NULL, &buffer);
663                 if (ACPI_FAILURE(status))
664                         buffer.pointer = NULL;
665                 dev->pnp.str_obj = buffer.pointer;
666                 result = device_create_file(&dev->dev, &dev_attr_description);
667                 if (result)
668                         goto end;
669         }
670
671         if (dev->pnp.type.bus_address)
672                 result = device_create_file(&dev->dev, &dev_attr_adr);
673         if (dev->pnp.unique_id)
674                 result = device_create_file(&dev->dev, &dev_attr_uid);
675
676         status = acpi_evaluate_integer(dev->handle, "_SUN", NULL, &sun);
677         if (ACPI_SUCCESS(status)) {
678                 dev->pnp.sun = (unsigned long)sun;
679                 result = device_create_file(&dev->dev, &dev_attr_sun);
680                 if (result)
681                         goto end;
682         } else {
683                 dev->pnp.sun = (unsigned long)-1;
684         }
685
686         /*
687          * If device has _EJ0, 'eject' file is created that is used to trigger
688          * hot-removal function from userland.
689          */
690         if (acpi_has_method(dev->handle, "_EJ0")) {
691                 result = device_create_file(&dev->dev, &dev_attr_eject);
692                 if (result)
693                         return result;
694         }
695
696         if (dev->flags.power_manageable) {
697                 result = device_create_file(&dev->dev, &dev_attr_power_state);
698                 if (result)
699                         return result;
700
701                 if (dev->power.flags.power_resources)
702                         result = device_create_file(&dev->dev,
703                                                     &dev_attr_real_power_state);
704         }
705
706 end:
707         return result;
708 }
709
710 static void acpi_device_remove_files(struct acpi_device *dev)
711 {
712         if (dev->flags.power_manageable) {
713                 device_remove_file(&dev->dev, &dev_attr_power_state);
714                 if (dev->power.flags.power_resources)
715                         device_remove_file(&dev->dev,
716                                            &dev_attr_real_power_state);
717         }
718
719         /*
720          * If device has _STR, remove 'description' file
721          */
722         if (acpi_has_method(dev->handle, "_STR")) {
723                 kfree(dev->pnp.str_obj);
724                 device_remove_file(&dev->dev, &dev_attr_description);
725         }
726         /*
727          * If device has _EJ0, remove 'eject' file.
728          */
729         if (acpi_has_method(dev->handle, "_EJ0"))
730                 device_remove_file(&dev->dev, &dev_attr_eject);
731
732         if (acpi_has_method(dev->handle, "_SUN"))
733                 device_remove_file(&dev->dev, &dev_attr_sun);
734
735         if (dev->pnp.unique_id)
736                 device_remove_file(&dev->dev, &dev_attr_uid);
737         if (dev->pnp.type.bus_address)
738                 device_remove_file(&dev->dev, &dev_attr_adr);
739         device_remove_file(&dev->dev, &dev_attr_modalias);
740         device_remove_file(&dev->dev, &dev_attr_hid);
741         if (dev->handle)
742                 device_remove_file(&dev->dev, &dev_attr_path);
743 }
744 /* --------------------------------------------------------------------------
745                         ACPI Bus operations
746    -------------------------------------------------------------------------- */
747
748 static const struct acpi_device_id *__acpi_match_device(
749         struct acpi_device *device, const struct acpi_device_id *ids)
750 {
751         const struct acpi_device_id *id;
752         struct acpi_hardware_id *hwid;
753
754         /*
755          * If the device is not present, it is unnecessary to load device
756          * driver for it.
757          */
758         if (!device->status.present)
759                 return NULL;
760
761         for (id = ids; id->id[0]; id++)
762                 list_for_each_entry(hwid, &device->pnp.ids, list)
763                         if (!strcmp((char *) id->id, hwid->id))
764                                 return id;
765
766         return NULL;
767 }
768
769 /**
770  * acpi_match_device - Match a struct device against a given list of ACPI IDs
771  * @ids: Array of struct acpi_device_id object to match against.
772  * @dev: The device structure to match.
773  *
774  * Check if @dev has a valid ACPI handle and if there is a struct acpi_device
775  * object for that handle and use that object to match against a given list of
776  * device IDs.
777  *
778  * Return a pointer to the first matching ID on success or %NULL on failure.
779  */
780 const struct acpi_device_id *acpi_match_device(const struct acpi_device_id *ids,
781                                                const struct device *dev)
782 {
783         struct acpi_device *adev;
784         acpi_handle handle = ACPI_HANDLE(dev);
785
786         if (!ids || !handle || acpi_bus_get_device(handle, &adev))
787                 return NULL;
788
789         return __acpi_match_device(adev, ids);
790 }
791 EXPORT_SYMBOL_GPL(acpi_match_device);
792
793 int acpi_match_device_ids(struct acpi_device *device,
794                           const struct acpi_device_id *ids)
795 {
796         return __acpi_match_device(device, ids) ? 0 : -ENOENT;
797 }
798 EXPORT_SYMBOL(acpi_match_device_ids);
799
800 static void acpi_free_power_resources_lists(struct acpi_device *device)
801 {
802         int i;
803
804         if (device->wakeup.flags.valid)
805                 acpi_power_resources_list_free(&device->wakeup.resources);
806
807         if (!device->flags.power_manageable)
808                 return;
809
810         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
811                 struct acpi_device_power_state *ps = &device->power.states[i];
812                 acpi_power_resources_list_free(&ps->resources);
813         }
814 }
815
816 static void acpi_device_release(struct device *dev)
817 {
818         struct acpi_device *acpi_dev = to_acpi_device(dev);
819
820         acpi_free_pnp_ids(&acpi_dev->pnp);
821         acpi_free_power_resources_lists(acpi_dev);
822         kfree(acpi_dev);
823 }
824
825 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
826 {
827         struct acpi_device *acpi_dev = to_acpi_device(dev);
828         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
829
830         return acpi_dev->flags.match_driver
831                 && !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
832 }
833
834 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
835 {
836         struct acpi_device *acpi_dev = to_acpi_device(dev);
837         int len;
838
839         if (list_empty(&acpi_dev->pnp.ids))
840                 return 0;
841
842         if (add_uevent_var(env, "MODALIAS="))
843                 return -ENOMEM;
844         len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
845                               sizeof(env->buf) - env->buflen);
846         if (len >= (sizeof(env->buf) - env->buflen))
847                 return -ENOMEM;
848         env->buflen += len;
849         return 0;
850 }
851
852 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
853 {
854         struct acpi_device *device = data;
855
856         device->driver->ops.notify(device, event);
857 }
858
859 static acpi_status acpi_device_notify_fixed(void *data)
860 {
861         struct acpi_device *device = data;
862
863         /* Fixed hardware devices have no handles */
864         acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
865         return AE_OK;
866 }
867
868 static int acpi_device_install_notify_handler(struct acpi_device *device)
869 {
870         acpi_status status;
871
872         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
873                 status =
874                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
875                                                      acpi_device_notify_fixed,
876                                                      device);
877         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
878                 status =
879                     acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
880                                                      acpi_device_notify_fixed,
881                                                      device);
882         else
883                 status = acpi_install_notify_handler(device->handle,
884                                                      ACPI_DEVICE_NOTIFY,
885                                                      acpi_device_notify,
886                                                      device);
887
888         if (ACPI_FAILURE(status))
889                 return -EINVAL;
890         return 0;
891 }
892
893 static void acpi_device_remove_notify_handler(struct acpi_device *device)
894 {
895         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
896                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
897                                                 acpi_device_notify_fixed);
898         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
899                 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
900                                                 acpi_device_notify_fixed);
901         else
902                 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
903                                            acpi_device_notify);
904 }
905
906 static int acpi_device_probe(struct device *dev)
907 {
908         struct acpi_device *acpi_dev = to_acpi_device(dev);
909         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
910         int ret;
911
912         if (acpi_dev->handler)
913                 return -EINVAL;
914
915         if (!acpi_drv->ops.add)
916                 return -ENOSYS;
917
918         ret = acpi_drv->ops.add(acpi_dev);
919         if (ret)
920                 return ret;
921
922         acpi_dev->driver = acpi_drv;
923         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
924                           "Driver [%s] successfully bound to device [%s]\n",
925                           acpi_drv->name, acpi_dev->pnp.bus_id));
926
927         if (acpi_drv->ops.notify) {
928                 ret = acpi_device_install_notify_handler(acpi_dev);
929                 if (ret) {
930                         if (acpi_drv->ops.remove)
931                                 acpi_drv->ops.remove(acpi_dev);
932
933                         acpi_dev->driver = NULL;
934                         acpi_dev->driver_data = NULL;
935                         return ret;
936                 }
937         }
938
939         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found driver [%s] for device [%s]\n",
940                           acpi_drv->name, acpi_dev->pnp.bus_id));
941         get_device(dev);
942         return 0;
943 }
944
945 static int acpi_device_remove(struct device * dev)
946 {
947         struct acpi_device *acpi_dev = to_acpi_device(dev);
948         struct acpi_driver *acpi_drv = acpi_dev->driver;
949
950         if (acpi_drv) {
951                 if (acpi_drv->ops.notify)
952                         acpi_device_remove_notify_handler(acpi_dev);
953                 if (acpi_drv->ops.remove)
954                         acpi_drv->ops.remove(acpi_dev);
955         }
956         acpi_dev->driver = NULL;
957         acpi_dev->driver_data = NULL;
958
959         put_device(dev);
960         return 0;
961 }
962
963 struct bus_type acpi_bus_type = {
964         .name           = "acpi",
965         .match          = acpi_bus_match,
966         .probe          = acpi_device_probe,
967         .remove         = acpi_device_remove,
968         .uevent         = acpi_device_uevent,
969 };
970
971 int acpi_device_add(struct acpi_device *device,
972                     void (*release)(struct device *))
973 {
974         int result;
975         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
976         int found = 0;
977
978         if (device->handle) {
979                 acpi_status status;
980
981                 status = acpi_attach_data(device->handle, acpi_bus_data_handler,
982                                           device);
983                 if (ACPI_FAILURE(status)) {
984                         acpi_handle_err(device->handle,
985                                         "Unable to attach device data\n");
986                         return -ENODEV;
987                 }
988         }
989
990         /*
991          * Linkage
992          * -------
993          * Link this device to its parent and siblings.
994          */
995         INIT_LIST_HEAD(&device->children);
996         INIT_LIST_HEAD(&device->node);
997         INIT_LIST_HEAD(&device->wakeup_list);
998         INIT_LIST_HEAD(&device->physical_node_list);
999         mutex_init(&device->physical_node_lock);
1000         INIT_LIST_HEAD(&device->power_dependent);
1001
1002         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
1003         if (!new_bus_id) {
1004                 pr_err(PREFIX "Memory allocation error\n");
1005                 result = -ENOMEM;
1006                 goto err_detach;
1007         }
1008
1009         mutex_lock(&acpi_device_lock);
1010         /*
1011          * Find suitable bus_id and instance number in acpi_bus_id_list
1012          * If failed, create one and link it into acpi_bus_id_list
1013          */
1014         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
1015                 if (!strcmp(acpi_device_bus_id->bus_id,
1016                             acpi_device_hid(device))) {
1017                         acpi_device_bus_id->instance_no++;
1018                         found = 1;
1019                         kfree(new_bus_id);
1020                         break;
1021                 }
1022         }
1023         if (!found) {
1024                 acpi_device_bus_id = new_bus_id;
1025                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
1026                 acpi_device_bus_id->instance_no = 0;
1027                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
1028         }
1029         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
1030
1031         if (device->parent)
1032                 list_add_tail(&device->node, &device->parent->children);
1033
1034         if (device->wakeup.flags.valid)
1035                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
1036         mutex_unlock(&acpi_device_lock);
1037
1038         if (device->parent)
1039                 device->dev.parent = &device->parent->dev;
1040         device->dev.bus = &acpi_bus_type;
1041         device->dev.release = release;
1042         result = device_add(&device->dev);
1043         if (result) {
1044                 dev_err(&device->dev, "Error registering device\n");
1045                 goto err;
1046         }
1047
1048         result = acpi_device_setup_files(device);
1049         if (result)
1050                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
1051                        dev_name(&device->dev));
1052
1053         return 0;
1054
1055  err:
1056         mutex_lock(&acpi_device_lock);
1057         if (device->parent)
1058                 list_del(&device->node);
1059         list_del(&device->wakeup_list);
1060         mutex_unlock(&acpi_device_lock);
1061
1062  err_detach:
1063         acpi_detach_data(device->handle, acpi_bus_data_handler);
1064         return result;
1065 }
1066
1067 static void acpi_device_unregister(struct acpi_device *device)
1068 {
1069         mutex_lock(&acpi_device_lock);
1070         if (device->parent)
1071                 list_del(&device->node);
1072
1073         list_del(&device->wakeup_list);
1074         mutex_unlock(&acpi_device_lock);
1075
1076         acpi_detach_data(device->handle, acpi_bus_data_handler);
1077
1078         acpi_power_add_remove_device(device, false);
1079         acpi_device_remove_files(device);
1080         if (device->remove)
1081                 device->remove(device);
1082
1083         device_del(&device->dev);
1084         /*
1085          * Transition the device to D3cold to drop the reference counts of all
1086          * power resources the device depends on and turn off the ones that have
1087          * no more references.
1088          */
1089         acpi_device_set_power(device, ACPI_STATE_D3_COLD);
1090         device->handle = NULL;
1091         put_device(&device->dev);
1092 }
1093
1094 /* --------------------------------------------------------------------------
1095                                  Driver Management
1096    -------------------------------------------------------------------------- */
1097 /**
1098  * acpi_bus_register_driver - register a driver with the ACPI bus
1099  * @driver: driver being registered
1100  *
1101  * Registers a driver with the ACPI bus.  Searches the namespace for all
1102  * devices that match the driver's criteria and binds.  Returns zero for
1103  * success or a negative error status for failure.
1104  */
1105 int acpi_bus_register_driver(struct acpi_driver *driver)
1106 {
1107         int ret;
1108
1109         if (acpi_disabled)
1110                 return -ENODEV;
1111         driver->drv.name = driver->name;
1112         driver->drv.bus = &acpi_bus_type;
1113         driver->drv.owner = driver->owner;
1114
1115         ret = driver_register(&driver->drv);
1116         return ret;
1117 }
1118
1119 EXPORT_SYMBOL(acpi_bus_register_driver);
1120
1121 /**
1122  * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
1123  * @driver: driver to unregister
1124  *
1125  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
1126  * devices that match the driver's criteria and unbinds.
1127  */
1128 void acpi_bus_unregister_driver(struct acpi_driver *driver)
1129 {
1130         driver_unregister(&driver->drv);
1131 }
1132
1133 EXPORT_SYMBOL(acpi_bus_unregister_driver);
1134
1135 /* --------------------------------------------------------------------------
1136                                  Device Enumeration
1137    -------------------------------------------------------------------------- */
1138 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
1139 {
1140         struct acpi_device *device = NULL;
1141         acpi_status status;
1142
1143         /*
1144          * Fixed hardware devices do not appear in the namespace and do not
1145          * have handles, but we fabricate acpi_devices for them, so we have
1146          * to deal with them specially.
1147          */
1148         if (!handle)
1149                 return acpi_root;
1150
1151         do {
1152                 status = acpi_get_parent(handle, &handle);
1153                 if (ACPI_FAILURE(status))
1154                         return status == AE_NULL_ENTRY ? NULL : acpi_root;
1155         } while (acpi_bus_get_device(handle, &device));
1156         return device;
1157 }
1158
1159 acpi_status
1160 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
1161 {
1162         acpi_status status;
1163         acpi_handle tmp;
1164         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
1165         union acpi_object *obj;
1166
1167         status = acpi_get_handle(handle, "_EJD", &tmp);
1168         if (ACPI_FAILURE(status))
1169                 return status;
1170
1171         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
1172         if (ACPI_SUCCESS(status)) {
1173                 obj = buffer.pointer;
1174                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
1175                                          ejd);
1176                 kfree(buffer.pointer);
1177         }
1178         return status;
1179 }
1180 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
1181
1182 void acpi_bus_data_handler(acpi_handle handle, void *context)
1183 {
1184
1185         /* TBD */
1186
1187         return;
1188 }
1189
1190 static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
1191                                         struct acpi_device_wakeup *wakeup)
1192 {
1193         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1194         union acpi_object *package = NULL;
1195         union acpi_object *element = NULL;
1196         acpi_status status;
1197         int err = -ENODATA;
1198
1199         if (!wakeup)
1200                 return -EINVAL;
1201
1202         INIT_LIST_HEAD(&wakeup->resources);
1203
1204         /* _PRW */
1205         status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
1206         if (ACPI_FAILURE(status)) {
1207                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
1208                 return err;
1209         }
1210
1211         package = (union acpi_object *)buffer.pointer;
1212
1213         if (!package || package->package.count < 2)
1214                 goto out;
1215
1216         element = &(package->package.elements[0]);
1217         if (!element)
1218                 goto out;
1219
1220         if (element->type == ACPI_TYPE_PACKAGE) {
1221                 if ((element->package.count < 2) ||
1222                     (element->package.elements[0].type !=
1223                      ACPI_TYPE_LOCAL_REFERENCE)
1224                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
1225                         goto out;
1226
1227                 wakeup->gpe_device =
1228                     element->package.elements[0].reference.handle;
1229                 wakeup->gpe_number =
1230                     (u32) element->package.elements[1].integer.value;
1231         } else if (element->type == ACPI_TYPE_INTEGER) {
1232                 wakeup->gpe_device = NULL;
1233                 wakeup->gpe_number = element->integer.value;
1234         } else {
1235                 goto out;
1236         }
1237
1238         element = &(package->package.elements[1]);
1239         if (element->type != ACPI_TYPE_INTEGER)
1240                 goto out;
1241
1242         wakeup->sleep_state = element->integer.value;
1243
1244         err = acpi_extract_power_resources(package, 2, &wakeup->resources);
1245         if (err)
1246                 goto out;
1247
1248         if (!list_empty(&wakeup->resources)) {
1249                 int sleep_state;
1250
1251                 err = acpi_power_wakeup_list_init(&wakeup->resources,
1252                                                   &sleep_state);
1253                 if (err) {
1254                         acpi_handle_warn(handle, "Retrieving current states "
1255                                          "of wakeup power resources failed\n");
1256                         acpi_power_resources_list_free(&wakeup->resources);
1257                         goto out;
1258                 }
1259                 if (sleep_state < wakeup->sleep_state) {
1260                         acpi_handle_warn(handle, "Overriding _PRW sleep state "
1261                                          "(S%d) by S%d from power resources\n",
1262                                          (int)wakeup->sleep_state, sleep_state);
1263                         wakeup->sleep_state = sleep_state;
1264                 }
1265         }
1266         acpi_setup_gpe_for_wake(handle, wakeup->gpe_device, wakeup->gpe_number);
1267
1268  out:
1269         kfree(buffer.pointer);
1270         return err;
1271 }
1272
1273 static void acpi_bus_set_run_wake_flags(struct acpi_device *device)
1274 {
1275         struct acpi_device_id button_device_ids[] = {
1276                 {"PNP0C0C", 0},
1277                 {"PNP0C0D", 0},
1278                 {"PNP0C0E", 0},
1279                 {"", 0},
1280         };
1281         acpi_status status;
1282         acpi_event_status event_status;
1283
1284         device->wakeup.flags.notifier_present = 0;
1285
1286         /* Power button, Lid switch always enable wakeup */
1287         if (!acpi_match_device_ids(device, button_device_ids)) {
1288                 device->wakeup.flags.run_wake = 1;
1289                 if (!acpi_match_device_ids(device, &button_device_ids[1])) {
1290                         /* Do not use Lid/sleep button for S5 wakeup */
1291                         if (device->wakeup.sleep_state == ACPI_STATE_S5)
1292                                 device->wakeup.sleep_state = ACPI_STATE_S4;
1293                 }
1294                 device_set_wakeup_capable(&device->dev, true);
1295                 return;
1296         }
1297
1298         status = acpi_get_gpe_status(device->wakeup.gpe_device,
1299                                         device->wakeup.gpe_number,
1300                                                 &event_status);
1301         if (status == AE_OK)
1302                 device->wakeup.flags.run_wake =
1303                                 !!(event_status & ACPI_EVENT_FLAG_HANDLE);
1304 }
1305
1306 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
1307 {
1308         int err;
1309
1310         /* Presence of _PRW indicates wake capable */
1311         if (!acpi_has_method(device->handle, "_PRW"))
1312                 return;
1313
1314         err = acpi_bus_extract_wakeup_device_power_package(device->handle,
1315                                                            &device->wakeup);
1316         if (err) {
1317                 dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
1318                 return;
1319         }
1320
1321         device->wakeup.flags.valid = 1;
1322         device->wakeup.prepare_count = 0;
1323         acpi_bus_set_run_wake_flags(device);
1324         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
1325          * system for the ACPI device with the _PRW object.
1326          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
1327          * So it is necessary to call _DSW object first. Only when it is not
1328          * present will the _PSW object used.
1329          */
1330         err = acpi_device_sleep_wake(device, 0, 0, 0);
1331         if (err)
1332                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1333                                 "error in _DSW or _PSW evaluation\n"));
1334 }
1335
1336 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
1337 {
1338         struct acpi_device_power_state *ps = &device->power.states[state];
1339         char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
1340         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1341         acpi_status status;
1342
1343         INIT_LIST_HEAD(&ps->resources);
1344
1345         /* Evaluate "_PRx" to get referenced power resources */
1346         status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
1347         if (ACPI_SUCCESS(status)) {
1348                 union acpi_object *package = buffer.pointer;
1349
1350                 if (buffer.length && package
1351                     && package->type == ACPI_TYPE_PACKAGE
1352                     && package->package.count) {
1353                         int err = acpi_extract_power_resources(package, 0,
1354                                                                &ps->resources);
1355                         if (!err)
1356                                 device->power.flags.power_resources = 1;
1357                 }
1358                 ACPI_FREE(buffer.pointer);
1359         }
1360
1361         /* Evaluate "_PSx" to see if we can do explicit sets */
1362         pathname[2] = 'S';
1363         if (acpi_has_method(device->handle, pathname))
1364                 ps->flags.explicit_set = 1;
1365
1366         /*
1367          * State is valid if there are means to put the device into it.
1368          * D3hot is only valid if _PR3 present.
1369          */
1370         if (!list_empty(&ps->resources)
1371             || (ps->flags.explicit_set && state < ACPI_STATE_D3_HOT)) {
1372                 ps->flags.valid = 1;
1373                 ps->flags.os_accessible = 1;
1374         }
1375
1376         ps->power = -1;         /* Unknown - driver assigned */
1377         ps->latency = -1;       /* Unknown - driver assigned */
1378 }
1379
1380 static void acpi_bus_get_power_flags(struct acpi_device *device)
1381 {
1382         u32 i;
1383
1384         /* Presence of _PS0|_PR0 indicates 'power manageable' */
1385         if (!acpi_has_method(device->handle, "_PS0") &&
1386             !acpi_has_method(device->handle, "_PR0"))
1387                 return;
1388
1389         device->flags.power_manageable = 1;
1390
1391         /*
1392          * Power Management Flags
1393          */
1394         if (acpi_has_method(device->handle, "_PSC"))
1395                 device->power.flags.explicit_get = 1;
1396         if (acpi_has_method(device->handle, "_IRC"))
1397                 device->power.flags.inrush_current = 1;
1398
1399         /*
1400          * Enumerate supported power management states
1401          */
1402         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
1403                 acpi_bus_init_power_state(device, i);
1404
1405         INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
1406
1407         /* Set defaults for D0 and D3 states (always valid) */
1408         device->power.states[ACPI_STATE_D0].flags.valid = 1;
1409         device->power.states[ACPI_STATE_D0].power = 100;
1410         device->power.states[ACPI_STATE_D3].flags.valid = 1;
1411         device->power.states[ACPI_STATE_D3].power = 0;
1412
1413         /* Set D3cold's explicit_set flag if _PS3 exists. */
1414         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set)
1415                 device->power.states[ACPI_STATE_D3_COLD].flags.explicit_set = 1;
1416
1417         /* Presence of _PS3 or _PRx means we can put the device into D3 cold */
1418         if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set ||
1419                         device->power.flags.power_resources)
1420                 device->power.states[ACPI_STATE_D3_COLD].flags.os_accessible = 1;
1421
1422         if (acpi_bus_init_power(device)) {
1423                 acpi_free_power_resources_lists(device);
1424                 device->flags.power_manageable = 0;
1425         }
1426 }
1427
1428 static void acpi_bus_get_flags(struct acpi_device *device)
1429 {
1430         /* Presence of _STA indicates 'dynamic_status' */
1431         if (acpi_has_method(device->handle, "_STA"))
1432                 device->flags.dynamic_status = 1;
1433
1434         /* Presence of _RMV indicates 'removable' */
1435         if (acpi_has_method(device->handle, "_RMV"))
1436                 device->flags.removable = 1;
1437
1438         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
1439         if (acpi_has_method(device->handle, "_EJD") ||
1440             acpi_has_method(device->handle, "_EJ0"))
1441                 device->flags.ejectable = 1;
1442 }
1443
1444 static void acpi_device_get_busid(struct acpi_device *device)
1445 {
1446         char bus_id[5] = { '?', 0 };
1447         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1448         int i = 0;
1449
1450         /*
1451          * Bus ID
1452          * ------
1453          * The device's Bus ID is simply the object name.
1454          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1455          */
1456         if (ACPI_IS_ROOT_DEVICE(device)) {
1457                 strcpy(device->pnp.bus_id, "ACPI");
1458                 return;
1459         }
1460
1461         switch (device->device_type) {
1462         case ACPI_BUS_TYPE_POWER_BUTTON:
1463                 strcpy(device->pnp.bus_id, "PWRF");
1464                 break;
1465         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1466                 strcpy(device->pnp.bus_id, "SLPF");
1467                 break;
1468         default:
1469                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1470                 /* Clean up trailing underscores (if any) */
1471                 for (i = 3; i > 1; i--) {
1472                         if (bus_id[i] == '_')
1473                                 bus_id[i] = '\0';
1474                         else
1475                                 break;
1476                 }
1477                 strcpy(device->pnp.bus_id, bus_id);
1478                 break;
1479         }
1480 }
1481
1482 /*
1483  * acpi_ata_match - see if an acpi object is an ATA device
1484  *
1485  * If an acpi object has one of the ACPI ATA methods defined,
1486  * then we can safely call it an ATA device.
1487  */
1488 bool acpi_ata_match(acpi_handle handle)
1489 {
1490         return acpi_has_method(handle, "_GTF") ||
1491                acpi_has_method(handle, "_GTM") ||
1492                acpi_has_method(handle, "_STM") ||
1493                acpi_has_method(handle, "_SDD");
1494 }
1495
1496 /*
1497  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1498  *
1499  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1500  * then we can safely call it an ejectable drive bay
1501  */
1502 bool acpi_bay_match(acpi_handle handle)
1503 {
1504         acpi_handle phandle;
1505
1506         if (!acpi_has_method(handle, "_EJ0"))
1507                 return false;
1508         if (acpi_ata_match(handle))
1509                 return true;
1510         if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1511                 return false;
1512
1513         return acpi_ata_match(phandle);
1514 }
1515
1516 /*
1517  * acpi_dock_match - see if an acpi object has a _DCK method
1518  */
1519 bool acpi_dock_match(acpi_handle handle)
1520 {
1521         return acpi_has_method(handle, "_DCK");
1522 }
1523
1524 const char *acpi_device_hid(struct acpi_device *device)
1525 {
1526         struct acpi_hardware_id *hid;
1527
1528         if (list_empty(&device->pnp.ids))
1529                 return dummy_hid;
1530
1531         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1532         return hid->id;
1533 }
1534 EXPORT_SYMBOL(acpi_device_hid);
1535
1536 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1537 {
1538         struct acpi_hardware_id *id;
1539
1540         id = kmalloc(sizeof(*id), GFP_KERNEL);
1541         if (!id)
1542                 return;
1543
1544         id->id = kstrdup(dev_id, GFP_KERNEL);
1545         if (!id->id) {
1546                 kfree(id);
1547                 return;
1548         }
1549
1550         list_add_tail(&id->list, &pnp->ids);
1551         pnp->type.hardware_id = 1;
1552 }
1553
1554 /*
1555  * Old IBM workstations have a DSDT bug wherein the SMBus object
1556  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1557  * prefix.  Work around this.
1558  */
1559 static bool acpi_ibm_smbus_match(acpi_handle handle)
1560 {
1561         char node_name[ACPI_PATH_SEGMENT_LENGTH];
1562         struct acpi_buffer path = { sizeof(node_name), node_name };
1563
1564         if (!dmi_name_in_vendors("IBM"))
1565                 return false;
1566
1567         /* Look for SMBS object */
1568         if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1569             strcmp("SMBS", path.pointer))
1570                 return false;
1571
1572         /* Does it have the necessary (but misnamed) methods? */
1573         if (acpi_has_method(handle, "SBI") &&
1574             acpi_has_method(handle, "SBR") &&
1575             acpi_has_method(handle, "SBW"))
1576                 return true;
1577
1578         return false;
1579 }
1580
1581 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1582                                 int device_type)
1583 {
1584         acpi_status status;
1585         struct acpi_device_info *info;
1586         struct acpi_pnp_device_id_list *cid_list;
1587         int i;
1588
1589         switch (device_type) {
1590         case ACPI_BUS_TYPE_DEVICE:
1591                 if (handle == ACPI_ROOT_OBJECT) {
1592                         acpi_add_id(pnp, ACPI_SYSTEM_HID);
1593                         break;
1594                 }
1595
1596                 status = acpi_get_object_info(handle, &info);
1597                 if (ACPI_FAILURE(status)) {
1598                         pr_err(PREFIX "%s: Error reading device info\n",
1599                                         __func__);
1600                         return;
1601                 }
1602
1603                 if (info->valid & ACPI_VALID_HID)
1604                         acpi_add_id(pnp, info->hardware_id.string);
1605                 if (info->valid & ACPI_VALID_CID) {
1606                         cid_list = &info->compatible_id_list;
1607                         for (i = 0; i < cid_list->count; i++)
1608                                 acpi_add_id(pnp, cid_list->ids[i].string);
1609                 }
1610                 if (info->valid & ACPI_VALID_ADR) {
1611                         pnp->bus_address = info->address;
1612                         pnp->type.bus_address = 1;
1613                 }
1614                 if (info->valid & ACPI_VALID_UID)
1615                         pnp->unique_id = kstrdup(info->unique_id.string,
1616                                                         GFP_KERNEL);
1617
1618                 kfree(info);
1619
1620                 /*
1621                  * Some devices don't reliably have _HIDs & _CIDs, so add
1622                  * synthetic HIDs to make sure drivers can find them.
1623                  */
1624                 if (acpi_is_video_device(handle))
1625                         acpi_add_id(pnp, ACPI_VIDEO_HID);
1626                 else if (acpi_bay_match(handle))
1627                         acpi_add_id(pnp, ACPI_BAY_HID);
1628                 else if (acpi_dock_match(handle))
1629                         acpi_add_id(pnp, ACPI_DOCK_HID);
1630                 else if (acpi_ibm_smbus_match(handle))
1631                         acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1632                 else if (list_empty(&pnp->ids) && handle == ACPI_ROOT_OBJECT) {
1633                         acpi_add_id(pnp, ACPI_BUS_HID); /* \_SB, LNXSYBUS */
1634                         strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1635                         strcpy(pnp->device_class, ACPI_BUS_CLASS);
1636                 }
1637
1638                 break;
1639         case ACPI_BUS_TYPE_POWER:
1640                 acpi_add_id(pnp, ACPI_POWER_HID);
1641                 break;
1642         case ACPI_BUS_TYPE_PROCESSOR:
1643                 acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1644                 break;
1645         case ACPI_BUS_TYPE_THERMAL:
1646                 acpi_add_id(pnp, ACPI_THERMAL_HID);
1647                 break;
1648         case ACPI_BUS_TYPE_POWER_BUTTON:
1649                 acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1650                 break;
1651         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1652                 acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1653                 break;
1654         }
1655 }
1656
1657 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1658 {
1659         struct acpi_hardware_id *id, *tmp;
1660
1661         list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1662                 kfree(id->id);
1663                 kfree(id);
1664         }
1665         kfree(pnp->unique_id);
1666 }
1667
1668 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1669                              int type, unsigned long long sta)
1670 {
1671         INIT_LIST_HEAD(&device->pnp.ids);
1672         device->device_type = type;
1673         device->handle = handle;
1674         device->parent = acpi_bus_get_parent(handle);
1675         STRUCT_TO_INT(device->status) = sta;
1676         acpi_device_get_busid(device);
1677         acpi_set_pnp_ids(handle, &device->pnp, type);
1678         acpi_bus_get_flags(device);
1679         device->flags.match_driver = false;
1680         device_initialize(&device->dev);
1681         dev_set_uevent_suppress(&device->dev, true);
1682 }
1683
1684 void acpi_device_add_finalize(struct acpi_device *device)
1685 {
1686         device->flags.match_driver = true;
1687         dev_set_uevent_suppress(&device->dev, false);
1688         kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1689 }
1690
1691 static int acpi_add_single_object(struct acpi_device **child,
1692                                   acpi_handle handle, int type,
1693                                   unsigned long long sta)
1694 {
1695         int result;
1696         struct acpi_device *device;
1697         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1698
1699         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1700         if (!device) {
1701                 printk(KERN_ERR PREFIX "Memory allocation error\n");
1702                 return -ENOMEM;
1703         }
1704
1705         acpi_init_device_object(device, handle, type, sta);
1706         acpi_bus_get_power_flags(device);
1707         acpi_bus_get_wakeup_device_flags(device);
1708
1709         result = acpi_device_add(device, acpi_device_release);
1710         if (result) {
1711                 acpi_device_release(&device->dev);
1712                 return result;
1713         }
1714
1715         acpi_power_add_remove_device(device, true);
1716         acpi_device_add_finalize(device);
1717         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1718         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1719                 dev_name(&device->dev), (char *) buffer.pointer,
1720                 device->parent ? dev_name(&device->parent->dev) : "(null)"));
1721         kfree(buffer.pointer);
1722         *child = device;
1723         return 0;
1724 }
1725
1726 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1727                                     unsigned long long *sta)
1728 {
1729         acpi_status status;
1730         acpi_object_type acpi_type;
1731
1732         status = acpi_get_type(handle, &acpi_type);
1733         if (ACPI_FAILURE(status))
1734                 return -ENODEV;
1735
1736         switch (acpi_type) {
1737         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
1738         case ACPI_TYPE_DEVICE:
1739                 *type = ACPI_BUS_TYPE_DEVICE;
1740                 status = acpi_bus_get_status_handle(handle, sta);
1741                 if (ACPI_FAILURE(status))
1742                         return -ENODEV;
1743                 break;
1744         case ACPI_TYPE_PROCESSOR:
1745                 *type = ACPI_BUS_TYPE_PROCESSOR;
1746                 status = acpi_bus_get_status_handle(handle, sta);
1747                 if (ACPI_FAILURE(status))
1748                         return -ENODEV;
1749                 break;
1750         case ACPI_TYPE_THERMAL:
1751                 *type = ACPI_BUS_TYPE_THERMAL;
1752                 *sta = ACPI_STA_DEFAULT;
1753                 break;
1754         case ACPI_TYPE_POWER:
1755                 *type = ACPI_BUS_TYPE_POWER;
1756                 *sta = ACPI_STA_DEFAULT;
1757                 break;
1758         default:
1759                 return -ENODEV;
1760         }
1761
1762         return 0;
1763 }
1764
1765 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1766                                        char *idstr,
1767                                        const struct acpi_device_id **matchid)
1768 {
1769         const struct acpi_device_id *devid;
1770
1771         for (devid = handler->ids; devid->id[0]; devid++)
1772                 if (!strcmp((char *)devid->id, idstr)) {
1773                         if (matchid)
1774                                 *matchid = devid;
1775
1776                         return true;
1777                 }
1778
1779         return false;
1780 }
1781
1782 static struct acpi_scan_handler *acpi_scan_match_handler(char *idstr,
1783                                         const struct acpi_device_id **matchid)
1784 {
1785         struct acpi_scan_handler *handler;
1786
1787         list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1788                 if (acpi_scan_handler_matching(handler, idstr, matchid))
1789                         return handler;
1790
1791         return NULL;
1792 }
1793
1794 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1795 {
1796         if (!!hotplug->enabled == !!val)
1797                 return;
1798
1799         mutex_lock(&acpi_scan_lock);
1800
1801         hotplug->enabled = val;
1802
1803         mutex_unlock(&acpi_scan_lock);
1804 }
1805
1806 static void acpi_scan_init_hotplug(acpi_handle handle, int type)
1807 {
1808         struct acpi_device_pnp pnp = {};
1809         struct acpi_hardware_id *hwid;
1810         struct acpi_scan_handler *handler;
1811
1812         INIT_LIST_HEAD(&pnp.ids);
1813         acpi_set_pnp_ids(handle, &pnp, type);
1814
1815         if (!pnp.type.hardware_id)
1816                 goto out;
1817
1818         /*
1819          * This relies on the fact that acpi_install_notify_handler() will not
1820          * install the same notify handler routine twice for the same handle.
1821          */
1822         list_for_each_entry(hwid, &pnp.ids, list) {
1823                 handler = acpi_scan_match_handler(hwid->id, NULL);
1824                 if (handler) {
1825                         acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
1826                                         acpi_hotplug_notify_cb, handler);
1827                         break;
1828                 }
1829         }
1830
1831 out:
1832         acpi_free_pnp_ids(&pnp);
1833 }
1834
1835 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
1836                                       void *not_used, void **return_value)
1837 {
1838         struct acpi_device *device = NULL;
1839         int type;
1840         unsigned long long sta;
1841         int result;
1842
1843         acpi_bus_get_device(handle, &device);
1844         if (device)
1845                 goto out;
1846
1847         result = acpi_bus_type_and_status(handle, &type, &sta);
1848         if (result)
1849                 return AE_OK;
1850
1851         if (type == ACPI_BUS_TYPE_POWER) {
1852                 acpi_add_power_resource(handle);
1853                 return AE_OK;
1854         }
1855
1856         acpi_scan_init_hotplug(handle, type);
1857
1858         if (!(sta & ACPI_STA_DEVICE_PRESENT) &&
1859             !(sta & ACPI_STA_DEVICE_FUNCTIONING)) {
1860                 struct acpi_device_wakeup wakeup;
1861
1862                 if (acpi_has_method(handle, "_PRW")) {
1863                         acpi_bus_extract_wakeup_device_power_package(handle,
1864                                                                      &wakeup);
1865                         acpi_power_resources_list_free(&wakeup.resources);
1866                 }
1867                 return AE_CTRL_DEPTH;
1868         }
1869
1870         acpi_add_single_object(&device, handle, type, sta);
1871         if (!device)
1872                 return AE_CTRL_DEPTH;
1873
1874  out:
1875         if (!*return_value)
1876                 *return_value = device;
1877
1878         return AE_OK;
1879 }
1880
1881 static int acpi_scan_attach_handler(struct acpi_device *device)
1882 {
1883         struct acpi_hardware_id *hwid;
1884         int ret = 0;
1885
1886         list_for_each_entry(hwid, &device->pnp.ids, list) {
1887                 const struct acpi_device_id *devid;
1888                 struct acpi_scan_handler *handler;
1889
1890                 handler = acpi_scan_match_handler(hwid->id, &devid);
1891                 if (handler) {
1892                         ret = handler->attach(device, devid);
1893                         if (ret > 0) {
1894                                 device->handler = handler;
1895                                 break;
1896                         } else if (ret < 0) {
1897                                 break;
1898                         }
1899                 }
1900         }
1901         return ret;
1902 }
1903
1904 static acpi_status acpi_bus_device_attach(acpi_handle handle, u32 lvl_not_used,
1905                                           void *not_used, void **ret_not_used)
1906 {
1907         struct acpi_device *device;
1908         unsigned long long sta_not_used;
1909         int ret;
1910
1911         /*
1912          * Ignore errors ignored by acpi_bus_check_add() to avoid terminating
1913          * namespace walks prematurely.
1914          */
1915         if (acpi_bus_type_and_status(handle, &ret, &sta_not_used))
1916                 return AE_OK;
1917
1918         if (acpi_bus_get_device(handle, &device))
1919                 return AE_CTRL_DEPTH;
1920
1921         ret = acpi_scan_attach_handler(device);
1922         if (ret)
1923                 return ret > 0 ? AE_OK : AE_CTRL_DEPTH;
1924
1925         ret = device_attach(&device->dev);
1926         return ret >= 0 ? AE_OK : AE_CTRL_DEPTH;
1927 }
1928
1929 /**
1930  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
1931  * @handle: Root of the namespace scope to scan.
1932  *
1933  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
1934  * found devices.
1935  *
1936  * If no devices were found, -ENODEV is returned, but it does not mean that
1937  * there has been a real error.  There just have been no suitable ACPI objects
1938  * in the table trunk from which the kernel could create a device and add an
1939  * appropriate driver.
1940  *
1941  * Must be called under acpi_scan_lock.
1942  */
1943 int acpi_bus_scan(acpi_handle handle)
1944 {
1945         void *device = NULL;
1946         int error = 0;
1947
1948         if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
1949                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1950                                     acpi_bus_check_add, NULL, NULL, &device);
1951
1952         if (!device)
1953                 error = -ENODEV;
1954         else if (ACPI_SUCCESS(acpi_bus_device_attach(handle, 0, NULL, NULL)))
1955                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1956                                     acpi_bus_device_attach, NULL, NULL, NULL);
1957
1958         return error;
1959 }
1960 EXPORT_SYMBOL(acpi_bus_scan);
1961
1962 static acpi_status acpi_bus_device_detach(acpi_handle handle, u32 lvl_not_used,
1963                                           void *not_used, void **ret_not_used)
1964 {
1965         struct acpi_device *device = NULL;
1966
1967         if (!acpi_bus_get_device(handle, &device)) {
1968                 struct acpi_scan_handler *dev_handler = device->handler;
1969
1970                 if (dev_handler) {
1971                         if (dev_handler->detach)
1972                                 dev_handler->detach(device);
1973
1974                         device->handler = NULL;
1975                 } else {
1976                         device_release_driver(&device->dev);
1977                 }
1978         }
1979         return AE_OK;
1980 }
1981
1982 static acpi_status acpi_bus_remove(acpi_handle handle, u32 lvl_not_used,
1983                                    void *not_used, void **ret_not_used)
1984 {
1985         struct acpi_device *device = NULL;
1986
1987         if (!acpi_bus_get_device(handle, &device))
1988                 acpi_device_unregister(device);
1989
1990         return AE_OK;
1991 }
1992
1993 /**
1994  * acpi_bus_trim - Remove ACPI device node and all of its descendants
1995  * @start: Root of the ACPI device nodes subtree to remove.
1996  *
1997  * Must be called under acpi_scan_lock.
1998  */
1999 void acpi_bus_trim(struct acpi_device *start)
2000 {
2001         /*
2002          * Execute acpi_bus_device_detach() as a post-order callback to detach
2003          * all ACPI drivers from the device nodes being removed.
2004          */
2005         acpi_walk_namespace(ACPI_TYPE_ANY, start->handle, ACPI_UINT32_MAX, NULL,
2006                             acpi_bus_device_detach, NULL, NULL);
2007         acpi_bus_device_detach(start->handle, 0, NULL, NULL);
2008         /*
2009          * Execute acpi_bus_remove() as a post-order callback to remove device
2010          * nodes in the given namespace scope.
2011          */
2012         acpi_walk_namespace(ACPI_TYPE_ANY, start->handle, ACPI_UINT32_MAX, NULL,
2013                             acpi_bus_remove, NULL, NULL);
2014         acpi_bus_remove(start->handle, 0, NULL, NULL);
2015 }
2016 EXPORT_SYMBOL_GPL(acpi_bus_trim);
2017
2018 static int acpi_bus_scan_fixed(void)
2019 {
2020         int result = 0;
2021
2022         /*
2023          * Enumerate all fixed-feature devices.
2024          */
2025         if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2026                 struct acpi_device *device = NULL;
2027
2028                 result = acpi_add_single_object(&device, NULL,
2029                                                 ACPI_BUS_TYPE_POWER_BUTTON,
2030                                                 ACPI_STA_DEFAULT);
2031                 if (result)
2032                         return result;
2033
2034                 result = device_attach(&device->dev);
2035                 if (result < 0)
2036                         return result;
2037
2038                 device_init_wakeup(&device->dev, true);
2039         }
2040
2041         if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2042                 struct acpi_device *device = NULL;
2043
2044                 result = acpi_add_single_object(&device, NULL,
2045                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
2046                                                 ACPI_STA_DEFAULT);
2047                 if (result)
2048                         return result;
2049
2050                 result = device_attach(&device->dev);
2051         }
2052
2053         return result < 0 ? result : 0;
2054 }
2055
2056 int __init acpi_scan_init(void)
2057 {
2058         int result;
2059
2060         result = bus_register(&acpi_bus_type);
2061         if (result) {
2062                 /* We don't want to quit even if we failed to add suspend/resume */
2063                 printk(KERN_ERR PREFIX "Could not register bus type\n");
2064         }
2065
2066         acpi_pci_root_init();
2067         acpi_pci_link_init();
2068         acpi_processor_init();
2069         acpi_platform_init();
2070         acpi_lpss_init();
2071         acpi_cmos_rtc_init();
2072         acpi_container_init();
2073         acpi_memory_hotplug_init();
2074         acpi_dock_init();
2075
2076         mutex_lock(&acpi_scan_lock);
2077         /*
2078          * Enumerate devices in the ACPI namespace.
2079          */
2080         result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2081         if (result)
2082                 goto out;
2083
2084         result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2085         if (result)
2086                 goto out;
2087
2088         result = acpi_bus_scan_fixed();
2089         if (result) {
2090                 acpi_device_unregister(acpi_root);
2091                 goto out;
2092         }
2093
2094         acpi_update_all_gpes();
2095
2096         acpi_pci_root_hp_init();
2097
2098  out:
2099         mutex_unlock(&acpi_scan_lock);
2100         return result;
2101 }