Merge branch 'acpi-video'
[firefly-linux-kernel-4.4.55.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 <asm/pgtable.h>
16
17 #include "internal.h"
18
19 #define _COMPONENT              ACPI_BUS_COMPONENT
20 ACPI_MODULE_NAME("scan");
21 extern struct acpi_device *acpi_root;
22
23 #define ACPI_BUS_CLASS                  "system_bus"
24 #define ACPI_BUS_HID                    "LNXSYBUS"
25 #define ACPI_BUS_DEVICE_NAME            "System Bus"
26
27 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
28
29 #define INVALID_ACPI_HANDLE     ((acpi_handle)empty_zero_page)
30
31 /*
32  * If set, devices will be hot-removed even if they cannot be put offline
33  * gracefully (from the kernel's standpoint).
34  */
35 bool acpi_force_hot_remove;
36
37 static const char *dummy_hid = "device";
38
39 static LIST_HEAD(acpi_dep_list);
40 static DEFINE_MUTEX(acpi_dep_list_lock);
41 static LIST_HEAD(acpi_bus_id_list);
42 static DEFINE_MUTEX(acpi_scan_lock);
43 static LIST_HEAD(acpi_scan_handlers_list);
44 DEFINE_MUTEX(acpi_device_lock);
45 LIST_HEAD(acpi_wakeup_device_list);
46 static DEFINE_MUTEX(acpi_hp_context_lock);
47
48 struct acpi_dep_data {
49         struct list_head node;
50         acpi_handle master;
51         acpi_handle slave;
52 };
53
54 struct acpi_device_bus_id{
55         char bus_id[15];
56         unsigned int instance_no;
57         struct list_head node;
58 };
59
60 void acpi_scan_lock_acquire(void)
61 {
62         mutex_lock(&acpi_scan_lock);
63 }
64 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
65
66 void acpi_scan_lock_release(void)
67 {
68         mutex_unlock(&acpi_scan_lock);
69 }
70 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
71
72 void acpi_lock_hp_context(void)
73 {
74         mutex_lock(&acpi_hp_context_lock);
75 }
76
77 void acpi_unlock_hp_context(void)
78 {
79         mutex_unlock(&acpi_hp_context_lock);
80 }
81
82 void acpi_initialize_hp_context(struct acpi_device *adev,
83                                 struct acpi_hotplug_context *hp,
84                                 int (*notify)(struct acpi_device *, u32),
85                                 void (*uevent)(struct acpi_device *, u32))
86 {
87         acpi_lock_hp_context();
88         hp->notify = notify;
89         hp->uevent = uevent;
90         acpi_set_hp_context(adev, hp);
91         acpi_unlock_hp_context();
92 }
93 EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
94
95 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
96 {
97         if (!handler)
98                 return -EINVAL;
99
100         list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
101         return 0;
102 }
103
104 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
105                                        const char *hotplug_profile_name)
106 {
107         int error;
108
109         error = acpi_scan_add_handler(handler);
110         if (error)
111                 return error;
112
113         acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
114         return 0;
115 }
116
117 /**
118  * create_pnp_modalias - Create hid/cid(s) string for modalias and uevent
119  * @acpi_dev: ACPI device object.
120  * @modalias: Buffer to print into.
121  * @size: Size of the buffer.
122  *
123  * Creates hid/cid(s) string needed for modalias and uevent
124  * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
125  * char *modalias: "acpi:IBM0001:ACPI0001"
126  * Return: 0: no _HID and no _CID
127  *         -EINVAL: output error
128  *         -ENOMEM: output is truncated
129 */
130 static int create_pnp_modalias(struct acpi_device *acpi_dev, char *modalias,
131                                int size)
132 {
133         int len;
134         int count;
135         struct acpi_hardware_id *id;
136
137         /*
138          * Since we skip ACPI_DT_NAMESPACE_HID from the modalias below, 0 should
139          * be returned if ACPI_DT_NAMESPACE_HID is the only ACPI/PNP ID in the
140          * device's list.
141          */
142         count = 0;
143         list_for_each_entry(id, &acpi_dev->pnp.ids, list)
144                 if (strcmp(id->id, ACPI_DT_NAMESPACE_HID))
145                         count++;
146
147         if (!count)
148                 return 0;
149
150         len = snprintf(modalias, size, "acpi:");
151         if (len <= 0)
152                 return len;
153
154         size -= len;
155
156         list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
157                 if (!strcmp(id->id, ACPI_DT_NAMESPACE_HID))
158                         continue;
159
160                 count = snprintf(&modalias[len], size, "%s:", id->id);
161                 if (count < 0)
162                         return -EINVAL;
163
164                 if (count >= size)
165                         return -ENOMEM;
166
167                 len += count;
168                 size -= count;
169         }
170         modalias[len] = '\0';
171         return len;
172 }
173
174 /**
175  * create_of_modalias - Creates DT compatible string for modalias and uevent
176  * @acpi_dev: ACPI device object.
177  * @modalias: Buffer to print into.
178  * @size: Size of the buffer.
179  *
180  * Expose DT compatible modalias as of:NnameTCcompatible.  This function should
181  * only be called for devices having ACPI_DT_NAMESPACE_HID in their list of
182  * ACPI/PNP IDs.
183  */
184 static int create_of_modalias(struct acpi_device *acpi_dev, char *modalias,
185                               int size)
186 {
187         struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
188         const union acpi_object *of_compatible, *obj;
189         int len, count;
190         int i, nval;
191         char *c;
192
193         acpi_get_name(acpi_dev->handle, ACPI_SINGLE_NAME, &buf);
194         /* DT strings are all in lower case */
195         for (c = buf.pointer; *c != '\0'; c++)
196                 *c = tolower(*c);
197
198         len = snprintf(modalias, size, "of:N%sT", (char *)buf.pointer);
199         ACPI_FREE(buf.pointer);
200
201         if (len <= 0)
202                 return len;
203
204         of_compatible = acpi_dev->data.of_compatible;
205         if (of_compatible->type == ACPI_TYPE_PACKAGE) {
206                 nval = of_compatible->package.count;
207                 obj = of_compatible->package.elements;
208         } else { /* Must be ACPI_TYPE_STRING. */
209                 nval = 1;
210                 obj = of_compatible;
211         }
212         for (i = 0; i < nval; i++, obj++) {
213                 count = snprintf(&modalias[len], size, "C%s",
214                                  obj->string.pointer);
215                 if (count < 0)
216                         return -EINVAL;
217
218                 if (count >= size)
219                         return -ENOMEM;
220
221                 len += count;
222                 size -= count;
223         }
224         modalias[len] = '\0';
225         return len;
226 }
227
228 /*
229  * acpi_companion_match() - Can we match via ACPI companion device
230  * @dev: Device in question
231  *
232  * Check if the given device has an ACPI companion and if that companion has
233  * a valid list of PNP IDs, and if the device is the first (primary) physical
234  * device associated with it.  Return the companion pointer if that's the case
235  * or NULL otherwise.
236  *
237  * If multiple physical devices are attached to a single ACPI companion, we need
238  * to be careful.  The usage scenario for this kind of relationship is that all
239  * of the physical devices in question use resources provided by the ACPI
240  * companion.  A typical case is an MFD device where all the sub-devices share
241  * the parent's ACPI companion.  In such cases we can only allow the primary
242  * (first) physical device to be matched with the help of the companion's PNP
243  * IDs.
244  *
245  * Additional physical devices sharing the ACPI companion can still use
246  * resources available from it but they will be matched normally using functions
247  * provided by their bus types (and analogously for their modalias).
248  */
249 static struct acpi_device *acpi_companion_match(const struct device *dev)
250 {
251         struct acpi_device *adev;
252         struct mutex *physical_node_lock;
253
254         adev = ACPI_COMPANION(dev);
255         if (!adev)
256                 return NULL;
257
258         if (list_empty(&adev->pnp.ids))
259                 return NULL;
260
261         physical_node_lock = &adev->physical_node_lock;
262         mutex_lock(physical_node_lock);
263         if (list_empty(&adev->physical_node_list)) {
264                 adev = NULL;
265         } else {
266                 const struct acpi_device_physical_node *node;
267
268                 node = list_first_entry(&adev->physical_node_list,
269                                         struct acpi_device_physical_node, node);
270                 if (node->dev != dev)
271                         adev = NULL;
272         }
273         mutex_unlock(physical_node_lock);
274
275         return adev;
276 }
277
278 static int __acpi_device_uevent_modalias(struct acpi_device *adev,
279                                          struct kobj_uevent_env *env)
280 {
281         int len;
282
283         if (!adev)
284                 return -ENODEV;
285
286         if (list_empty(&adev->pnp.ids))
287                 return 0;
288
289         if (add_uevent_var(env, "MODALIAS="))
290                 return -ENOMEM;
291
292         len = create_pnp_modalias(adev, &env->buf[env->buflen - 1],
293                                   sizeof(env->buf) - env->buflen);
294         if (len < 0)
295                 return len;
296
297         env->buflen += len;
298         if (!adev->data.of_compatible)
299                 return 0;
300
301         if (len > 0 && add_uevent_var(env, "MODALIAS="))
302                 return -ENOMEM;
303
304         len = create_of_modalias(adev, &env->buf[env->buflen - 1],
305                                  sizeof(env->buf) - env->buflen);
306         if (len < 0)
307                 return len;
308
309         env->buflen += len;
310
311         return 0;
312 }
313
314 /*
315  * Creates uevent modalias field for ACPI enumerated devices.
316  * Because the other buses does not support ACPI HIDs & CIDs.
317  * e.g. for a device with hid:IBM0001 and cid:ACPI0001 you get:
318  * "acpi:IBM0001:ACPI0001"
319  */
320 int acpi_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
321 {
322         return __acpi_device_uevent_modalias(acpi_companion_match(dev), env);
323 }
324 EXPORT_SYMBOL_GPL(acpi_device_uevent_modalias);
325
326 static int __acpi_device_modalias(struct acpi_device *adev, char *buf, int size)
327 {
328         int len, count;
329
330         if (!adev)
331                 return -ENODEV;
332
333         if (list_empty(&adev->pnp.ids))
334                 return 0;
335
336         len = create_pnp_modalias(adev, buf, size - 1);
337         if (len < 0) {
338                 return len;
339         } else if (len > 0) {
340                 buf[len++] = '\n';
341                 size -= len;
342         }
343         if (!adev->data.of_compatible)
344                 return len;
345
346         count = create_of_modalias(adev, buf + len, size - 1);
347         if (count < 0) {
348                 return count;
349         } else if (count > 0) {
350                 len += count;
351                 buf[len++] = '\n';
352         }
353
354         return len;
355 }
356
357 /*
358  * Creates modalias sysfs attribute for ACPI enumerated devices.
359  * Because the other buses does not support ACPI HIDs & CIDs.
360  * e.g. for a device with hid:IBM0001 and cid:ACPI0001 you get:
361  * "acpi:IBM0001:ACPI0001"
362  */
363 int acpi_device_modalias(struct device *dev, char *buf, int size)
364 {
365         return __acpi_device_modalias(acpi_companion_match(dev), buf, size);
366 }
367 EXPORT_SYMBOL_GPL(acpi_device_modalias);
368
369 static ssize_t
370 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
371         return __acpi_device_modalias(to_acpi_device(dev), buf, 1024);
372 }
373 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
374
375 bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
376 {
377         struct acpi_device_physical_node *pn;
378         bool offline = true;
379
380         /*
381          * acpi_container_offline() calls this for all of the container's
382          * children under the container's physical_node_lock lock.
383          */
384         mutex_lock_nested(&adev->physical_node_lock, SINGLE_DEPTH_NESTING);
385
386         list_for_each_entry(pn, &adev->physical_node_list, node)
387                 if (device_supports_offline(pn->dev) && !pn->dev->offline) {
388                         if (uevent)
389                                 kobject_uevent(&pn->dev->kobj, KOBJ_CHANGE);
390
391                         offline = false;
392                         break;
393                 }
394
395         mutex_unlock(&adev->physical_node_lock);
396         return offline;
397 }
398
399 static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
400                                     void **ret_p)
401 {
402         struct acpi_device *device = NULL;
403         struct acpi_device_physical_node *pn;
404         bool second_pass = (bool)data;
405         acpi_status status = AE_OK;
406
407         if (acpi_bus_get_device(handle, &device))
408                 return AE_OK;
409
410         if (device->handler && !device->handler->hotplug.enabled) {
411                 *ret_p = &device->dev;
412                 return AE_SUPPORT;
413         }
414
415         mutex_lock(&device->physical_node_lock);
416
417         list_for_each_entry(pn, &device->physical_node_list, node) {
418                 int ret;
419
420                 if (second_pass) {
421                         /* Skip devices offlined by the first pass. */
422                         if (pn->put_online)
423                                 continue;
424                 } else {
425                         pn->put_online = false;
426                 }
427                 ret = device_offline(pn->dev);
428                 if (acpi_force_hot_remove)
429                         continue;
430
431                 if (ret >= 0) {
432                         pn->put_online = !ret;
433                 } else {
434                         *ret_p = pn->dev;
435                         if (second_pass) {
436                                 status = AE_ERROR;
437                                 break;
438                         }
439                 }
440         }
441
442         mutex_unlock(&device->physical_node_lock);
443
444         return status;
445 }
446
447 static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
448                                    void **ret_p)
449 {
450         struct acpi_device *device = NULL;
451         struct acpi_device_physical_node *pn;
452
453         if (acpi_bus_get_device(handle, &device))
454                 return AE_OK;
455
456         mutex_lock(&device->physical_node_lock);
457
458         list_for_each_entry(pn, &device->physical_node_list, node)
459                 if (pn->put_online) {
460                         device_online(pn->dev);
461                         pn->put_online = false;
462                 }
463
464         mutex_unlock(&device->physical_node_lock);
465
466         return AE_OK;
467 }
468
469 static int acpi_scan_try_to_offline(struct acpi_device *device)
470 {
471         acpi_handle handle = device->handle;
472         struct device *errdev = NULL;
473         acpi_status status;
474
475         /*
476          * Carry out two passes here and ignore errors in the first pass,
477          * because if the devices in question are memory blocks and
478          * CONFIG_MEMCG is set, one of the blocks may hold data structures
479          * that the other blocks depend on, but it is not known in advance which
480          * block holds them.
481          *
482          * If the first pass is successful, the second one isn't needed, though.
483          */
484         status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
485                                      NULL, acpi_bus_offline, (void *)false,
486                                      (void **)&errdev);
487         if (status == AE_SUPPORT) {
488                 dev_warn(errdev, "Offline disabled.\n");
489                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
490                                     acpi_bus_online, NULL, NULL, NULL);
491                 return -EPERM;
492         }
493         acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
494         if (errdev) {
495                 errdev = NULL;
496                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
497                                     NULL, acpi_bus_offline, (void *)true,
498                                     (void **)&errdev);
499                 if (!errdev || acpi_force_hot_remove)
500                         acpi_bus_offline(handle, 0, (void *)true,
501                                          (void **)&errdev);
502
503                 if (errdev && !acpi_force_hot_remove) {
504                         dev_warn(errdev, "Offline failed.\n");
505                         acpi_bus_online(handle, 0, NULL, NULL);
506                         acpi_walk_namespace(ACPI_TYPE_ANY, handle,
507                                             ACPI_UINT32_MAX, acpi_bus_online,
508                                             NULL, NULL, NULL);
509                         return -EBUSY;
510                 }
511         }
512         return 0;
513 }
514
515 static int acpi_scan_hot_remove(struct acpi_device *device)
516 {
517         acpi_handle handle = device->handle;
518         unsigned long long sta;
519         acpi_status status;
520
521         if (device->handler && device->handler->hotplug.demand_offline
522             && !acpi_force_hot_remove) {
523                 if (!acpi_scan_is_offline(device, true))
524                         return -EBUSY;
525         } else {
526                 int error = acpi_scan_try_to_offline(device);
527                 if (error)
528                         return error;
529         }
530
531         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
532                 "Hot-removing device %s...\n", dev_name(&device->dev)));
533
534         acpi_bus_trim(device);
535
536         acpi_evaluate_lck(handle, 0);
537         /*
538          * TBD: _EJD support.
539          */
540         status = acpi_evaluate_ej0(handle);
541         if (status == AE_NOT_FOUND)
542                 return -ENODEV;
543         else if (ACPI_FAILURE(status))
544                 return -EIO;
545
546         /*
547          * Verify if eject was indeed successful.  If not, log an error
548          * message.  No need to call _OST since _EJ0 call was made OK.
549          */
550         status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
551         if (ACPI_FAILURE(status)) {
552                 acpi_handle_warn(handle,
553                         "Status check after eject failed (0x%x)\n", status);
554         } else if (sta & ACPI_STA_DEVICE_ENABLED) {
555                 acpi_handle_warn(handle,
556                         "Eject incomplete - status 0x%llx\n", sta);
557         }
558
559         return 0;
560 }
561
562 static int acpi_scan_device_not_present(struct acpi_device *adev)
563 {
564         if (!acpi_device_enumerated(adev)) {
565                 dev_warn(&adev->dev, "Still not present\n");
566                 return -EALREADY;
567         }
568         acpi_bus_trim(adev);
569         return 0;
570 }
571
572 static int acpi_scan_device_check(struct acpi_device *adev)
573 {
574         int error;
575
576         acpi_bus_get_status(adev);
577         if (adev->status.present || adev->status.functional) {
578                 /*
579                  * This function is only called for device objects for which
580                  * matching scan handlers exist.  The only situation in which
581                  * the scan handler is not attached to this device object yet
582                  * is when the device has just appeared (either it wasn't
583                  * present at all before or it was removed and then added
584                  * again).
585                  */
586                 if (adev->handler) {
587                         dev_warn(&adev->dev, "Already enumerated\n");
588                         return -EALREADY;
589                 }
590                 error = acpi_bus_scan(adev->handle);
591                 if (error) {
592                         dev_warn(&adev->dev, "Namespace scan failure\n");
593                         return error;
594                 }
595                 if (!adev->handler) {
596                         dev_warn(&adev->dev, "Enumeration failure\n");
597                         error = -ENODEV;
598                 }
599         } else {
600                 error = acpi_scan_device_not_present(adev);
601         }
602         return error;
603 }
604
605 static int acpi_scan_bus_check(struct acpi_device *adev)
606 {
607         struct acpi_scan_handler *handler = adev->handler;
608         struct acpi_device *child;
609         int error;
610
611         acpi_bus_get_status(adev);
612         if (!(adev->status.present || adev->status.functional)) {
613                 acpi_scan_device_not_present(adev);
614                 return 0;
615         }
616         if (handler && handler->hotplug.scan_dependent)
617                 return handler->hotplug.scan_dependent(adev);
618
619         error = acpi_bus_scan(adev->handle);
620         if (error) {
621                 dev_warn(&adev->dev, "Namespace scan failure\n");
622                 return error;
623         }
624         list_for_each_entry(child, &adev->children, node) {
625                 error = acpi_scan_bus_check(child);
626                 if (error)
627                         return error;
628         }
629         return 0;
630 }
631
632 static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type)
633 {
634         switch (type) {
635         case ACPI_NOTIFY_BUS_CHECK:
636                 return acpi_scan_bus_check(adev);
637         case ACPI_NOTIFY_DEVICE_CHECK:
638                 return acpi_scan_device_check(adev);
639         case ACPI_NOTIFY_EJECT_REQUEST:
640         case ACPI_OST_EC_OSPM_EJECT:
641                 if (adev->handler && !adev->handler->hotplug.enabled) {
642                         dev_info(&adev->dev, "Eject disabled\n");
643                         return -EPERM;
644                 }
645                 acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST,
646                                   ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
647                 return acpi_scan_hot_remove(adev);
648         }
649         return -EINVAL;
650 }
651
652 void acpi_device_hotplug(struct acpi_device *adev, u32 src)
653 {
654         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
655         int error = -ENODEV;
656
657         lock_device_hotplug();
658         mutex_lock(&acpi_scan_lock);
659
660         /*
661          * The device object's ACPI handle cannot become invalid as long as we
662          * are holding acpi_scan_lock, but it might have become invalid before
663          * that lock was acquired.
664          */
665         if (adev->handle == INVALID_ACPI_HANDLE)
666                 goto err_out;
667
668         if (adev->flags.is_dock_station) {
669                 error = dock_notify(adev, src);
670         } else if (adev->flags.hotplug_notify) {
671                 error = acpi_generic_hotplug_event(adev, src);
672                 if (error == -EPERM) {
673                         ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
674                         goto err_out;
675                 }
676         } else {
677                 int (*notify)(struct acpi_device *, u32);
678
679                 acpi_lock_hp_context();
680                 notify = adev->hp ? adev->hp->notify : NULL;
681                 acpi_unlock_hp_context();
682                 /*
683                  * There may be additional notify handlers for device objects
684                  * without the .event() callback, so ignore them here.
685                  */
686                 if (notify)
687                         error = notify(adev, src);
688                 else
689                         goto out;
690         }
691         if (!error)
692                 ost_code = ACPI_OST_SC_SUCCESS;
693
694  err_out:
695         acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
696
697  out:
698         acpi_bus_put_acpi_device(adev);
699         mutex_unlock(&acpi_scan_lock);
700         unlock_device_hotplug();
701 }
702
703 static ssize_t real_power_state_show(struct device *dev,
704                                      struct device_attribute *attr, char *buf)
705 {
706         struct acpi_device *adev = to_acpi_device(dev);
707         int state;
708         int ret;
709
710         ret = acpi_device_get_power(adev, &state);
711         if (ret)
712                 return ret;
713
714         return sprintf(buf, "%s\n", acpi_power_state_string(state));
715 }
716
717 static DEVICE_ATTR(real_power_state, 0444, real_power_state_show, NULL);
718
719 static ssize_t power_state_show(struct device *dev,
720                                 struct device_attribute *attr, char *buf)
721 {
722         struct acpi_device *adev = to_acpi_device(dev);
723
724         return sprintf(buf, "%s\n", acpi_power_state_string(adev->power.state));
725 }
726
727 static DEVICE_ATTR(power_state, 0444, power_state_show, NULL);
728
729 static ssize_t
730 acpi_eject_store(struct device *d, struct device_attribute *attr,
731                 const char *buf, size_t count)
732 {
733         struct acpi_device *acpi_device = to_acpi_device(d);
734         acpi_object_type not_used;
735         acpi_status status;
736
737         if (!count || buf[0] != '1')
738                 return -EINVAL;
739
740         if ((!acpi_device->handler || !acpi_device->handler->hotplug.enabled)
741             && !acpi_device->driver)
742                 return -ENODEV;
743
744         status = acpi_get_type(acpi_device->handle, &not_used);
745         if (ACPI_FAILURE(status) || !acpi_device->flags.ejectable)
746                 return -ENODEV;
747
748         get_device(&acpi_device->dev);
749         status = acpi_hotplug_schedule(acpi_device, ACPI_OST_EC_OSPM_EJECT);
750         if (ACPI_SUCCESS(status))
751                 return count;
752
753         put_device(&acpi_device->dev);
754         acpi_evaluate_ost(acpi_device->handle, ACPI_OST_EC_OSPM_EJECT,
755                           ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL);
756         return status == AE_NO_MEMORY ? -ENOMEM : -EAGAIN;
757 }
758
759 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
760
761 static ssize_t
762 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
763         struct acpi_device *acpi_dev = to_acpi_device(dev);
764
765         return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
766 }
767 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
768
769 static ssize_t acpi_device_uid_show(struct device *dev,
770                                     struct device_attribute *attr, char *buf)
771 {
772         struct acpi_device *acpi_dev = to_acpi_device(dev);
773
774         return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id);
775 }
776 static DEVICE_ATTR(uid, 0444, acpi_device_uid_show, NULL);
777
778 static ssize_t acpi_device_adr_show(struct device *dev,
779                                     struct device_attribute *attr, char *buf)
780 {
781         struct acpi_device *acpi_dev = to_acpi_device(dev);
782
783         return sprintf(buf, "0x%08x\n",
784                        (unsigned int)(acpi_dev->pnp.bus_address));
785 }
786 static DEVICE_ATTR(adr, 0444, acpi_device_adr_show, NULL);
787
788 static ssize_t
789 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
790         struct acpi_device *acpi_dev = to_acpi_device(dev);
791         struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
792         int result;
793
794         result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
795         if (result)
796                 goto end;
797
798         result = sprintf(buf, "%s\n", (char*)path.pointer);
799         kfree(path.pointer);
800 end:
801         return result;
802 }
803 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
804
805 /* sysfs file that shows description text from the ACPI _STR method */
806 static ssize_t description_show(struct device *dev,
807                                 struct device_attribute *attr,
808                                 char *buf) {
809         struct acpi_device *acpi_dev = to_acpi_device(dev);
810         int result;
811
812         if (acpi_dev->pnp.str_obj == NULL)
813                 return 0;
814
815         /*
816          * The _STR object contains a Unicode identifier for a device.
817          * We need to convert to utf-8 so it can be displayed.
818          */
819         result = utf16s_to_utf8s(
820                 (wchar_t *)acpi_dev->pnp.str_obj->buffer.pointer,
821                 acpi_dev->pnp.str_obj->buffer.length,
822                 UTF16_LITTLE_ENDIAN, buf,
823                 PAGE_SIZE);
824
825         buf[result++] = '\n';
826
827         return result;
828 }
829 static DEVICE_ATTR(description, 0444, description_show, NULL);
830
831 static ssize_t
832 acpi_device_sun_show(struct device *dev, struct device_attribute *attr,
833                      char *buf) {
834         struct acpi_device *acpi_dev = to_acpi_device(dev);
835         acpi_status status;
836         unsigned long long sun;
837
838         status = acpi_evaluate_integer(acpi_dev->handle, "_SUN", NULL, &sun);
839         if (ACPI_FAILURE(status))
840                 return -ENODEV;
841
842         return sprintf(buf, "%llu\n", sun);
843 }
844 static DEVICE_ATTR(sun, 0444, acpi_device_sun_show, NULL);
845
846 static ssize_t status_show(struct device *dev, struct device_attribute *attr,
847                                 char *buf) {
848         struct acpi_device *acpi_dev = to_acpi_device(dev);
849         acpi_status status;
850         unsigned long long sta;
851
852         status = acpi_evaluate_integer(acpi_dev->handle, "_STA", NULL, &sta);
853         if (ACPI_FAILURE(status))
854                 return -ENODEV;
855
856         return sprintf(buf, "%llu\n", sta);
857 }
858 static DEVICE_ATTR_RO(status);
859
860 static int acpi_device_setup_files(struct acpi_device *dev)
861 {
862         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
863         acpi_status status;
864         int result = 0;
865
866         /*
867          * Devices gotten from FADT don't have a "path" attribute
868          */
869         if (dev->handle) {
870                 result = device_create_file(&dev->dev, &dev_attr_path);
871                 if (result)
872                         goto end;
873         }
874
875         if (!list_empty(&dev->pnp.ids)) {
876                 result = device_create_file(&dev->dev, &dev_attr_hid);
877                 if (result)
878                         goto end;
879
880                 result = device_create_file(&dev->dev, &dev_attr_modalias);
881                 if (result)
882                         goto end;
883         }
884
885         /*
886          * If device has _STR, 'description' file is created
887          */
888         if (acpi_has_method(dev->handle, "_STR")) {
889                 status = acpi_evaluate_object(dev->handle, "_STR",
890                                         NULL, &buffer);
891                 if (ACPI_FAILURE(status))
892                         buffer.pointer = NULL;
893                 dev->pnp.str_obj = buffer.pointer;
894                 result = device_create_file(&dev->dev, &dev_attr_description);
895                 if (result)
896                         goto end;
897         }
898
899         if (dev->pnp.type.bus_address)
900                 result = device_create_file(&dev->dev, &dev_attr_adr);
901         if (dev->pnp.unique_id)
902                 result = device_create_file(&dev->dev, &dev_attr_uid);
903
904         if (acpi_has_method(dev->handle, "_SUN")) {
905                 result = device_create_file(&dev->dev, &dev_attr_sun);
906                 if (result)
907                         goto end;
908         }
909
910         if (acpi_has_method(dev->handle, "_STA")) {
911                 result = device_create_file(&dev->dev, &dev_attr_status);
912                 if (result)
913                         goto end;
914         }
915
916         /*
917          * If device has _EJ0, 'eject' file is created that is used to trigger
918          * hot-removal function from userland.
919          */
920         if (acpi_has_method(dev->handle, "_EJ0")) {
921                 result = device_create_file(&dev->dev, &dev_attr_eject);
922                 if (result)
923                         return result;
924         }
925
926         if (dev->flags.power_manageable) {
927                 result = device_create_file(&dev->dev, &dev_attr_power_state);
928                 if (result)
929                         return result;
930
931                 if (dev->power.flags.power_resources)
932                         result = device_create_file(&dev->dev,
933                                                     &dev_attr_real_power_state);
934         }
935
936 end:
937         return result;
938 }
939
940 static void acpi_device_remove_files(struct acpi_device *dev)
941 {
942         if (dev->flags.power_manageable) {
943                 device_remove_file(&dev->dev, &dev_attr_power_state);
944                 if (dev->power.flags.power_resources)
945                         device_remove_file(&dev->dev,
946                                            &dev_attr_real_power_state);
947         }
948
949         /*
950          * If device has _STR, remove 'description' file
951          */
952         if (acpi_has_method(dev->handle, "_STR")) {
953                 kfree(dev->pnp.str_obj);
954                 device_remove_file(&dev->dev, &dev_attr_description);
955         }
956         /*
957          * If device has _EJ0, remove 'eject' file.
958          */
959         if (acpi_has_method(dev->handle, "_EJ0"))
960                 device_remove_file(&dev->dev, &dev_attr_eject);
961
962         if (acpi_has_method(dev->handle, "_SUN"))
963                 device_remove_file(&dev->dev, &dev_attr_sun);
964
965         if (dev->pnp.unique_id)
966                 device_remove_file(&dev->dev, &dev_attr_uid);
967         if (dev->pnp.type.bus_address)
968                 device_remove_file(&dev->dev, &dev_attr_adr);
969         device_remove_file(&dev->dev, &dev_attr_modalias);
970         device_remove_file(&dev->dev, &dev_attr_hid);
971         if (acpi_has_method(dev->handle, "_STA"))
972                 device_remove_file(&dev->dev, &dev_attr_status);
973         if (dev->handle)
974                 device_remove_file(&dev->dev, &dev_attr_path);
975 }
976 /* --------------------------------------------------------------------------
977                         ACPI Bus operations
978    -------------------------------------------------------------------------- */
979
980 /**
981  * acpi_of_match_device - Match device object using the "compatible" property.
982  * @adev: ACPI device object to match.
983  * @of_match_table: List of device IDs to match against.
984  *
985  * If @dev has an ACPI companion which has ACPI_DT_NAMESPACE_HID in its list of
986  * identifiers and a _DSD object with the "compatible" property, use that
987  * property to match against the given list of identifiers.
988  */
989 static bool acpi_of_match_device(struct acpi_device *adev,
990                                  const struct of_device_id *of_match_table)
991 {
992         const union acpi_object *of_compatible, *obj;
993         int i, nval;
994
995         if (!adev)
996                 return false;
997
998         of_compatible = adev->data.of_compatible;
999         if (!of_match_table || !of_compatible)
1000                 return false;
1001
1002         if (of_compatible->type == ACPI_TYPE_PACKAGE) {
1003                 nval = of_compatible->package.count;
1004                 obj = of_compatible->package.elements;
1005         } else { /* Must be ACPI_TYPE_STRING. */
1006                 nval = 1;
1007                 obj = of_compatible;
1008         }
1009         /* Now we can look for the driver DT compatible strings */
1010         for (i = 0; i < nval; i++, obj++) {
1011                 const struct of_device_id *id;
1012
1013                 for (id = of_match_table; id->compatible[0]; id++)
1014                         if (!strcasecmp(obj->string.pointer, id->compatible))
1015                                 return true;
1016         }
1017
1018         return false;
1019 }
1020
1021 static const struct acpi_device_id *__acpi_match_device(
1022         struct acpi_device *device,
1023         const struct acpi_device_id *ids,
1024         const struct of_device_id *of_ids)
1025 {
1026         const struct acpi_device_id *id;
1027         struct acpi_hardware_id *hwid;
1028
1029         /*
1030          * If the device is not present, it is unnecessary to load device
1031          * driver for it.
1032          */
1033         if (!device || !device->status.present)
1034                 return NULL;
1035
1036         list_for_each_entry(hwid, &device->pnp.ids, list) {
1037                 /* First, check the ACPI/PNP IDs provided by the caller. */
1038                 for (id = ids; id->id[0]; id++)
1039                         if (!strcmp((char *) id->id, hwid->id))
1040                                 return id;
1041
1042                 /*
1043                  * Next, check ACPI_DT_NAMESPACE_HID and try to match the
1044                  * "compatible" property if found.
1045                  *
1046                  * The id returned by the below is not valid, but the only
1047                  * caller passing non-NULL of_ids here is only interested in
1048                  * whether or not the return value is NULL.
1049                  */
1050                 if (!strcmp(ACPI_DT_NAMESPACE_HID, hwid->id)
1051                     && acpi_of_match_device(device, of_ids))
1052                         return id;
1053         }
1054         return NULL;
1055 }
1056
1057 /**
1058  * acpi_match_device - Match a struct device against a given list of ACPI IDs
1059  * @ids: Array of struct acpi_device_id object to match against.
1060  * @dev: The device structure to match.
1061  *
1062  * Check if @dev has a valid ACPI handle and if there is a struct acpi_device
1063  * object for that handle and use that object to match against a given list of
1064  * device IDs.
1065  *
1066  * Return a pointer to the first matching ID on success or %NULL on failure.
1067  */
1068 const struct acpi_device_id *acpi_match_device(const struct acpi_device_id *ids,
1069                                                const struct device *dev)
1070 {
1071         return __acpi_match_device(acpi_companion_match(dev), ids, NULL);
1072 }
1073 EXPORT_SYMBOL_GPL(acpi_match_device);
1074
1075 int acpi_match_device_ids(struct acpi_device *device,
1076                           const struct acpi_device_id *ids)
1077 {
1078         return __acpi_match_device(device, ids, NULL) ? 0 : -ENOENT;
1079 }
1080 EXPORT_SYMBOL(acpi_match_device_ids);
1081
1082 bool acpi_driver_match_device(struct device *dev,
1083                               const struct device_driver *drv)
1084 {
1085         if (!drv->acpi_match_table)
1086                 return acpi_of_match_device(ACPI_COMPANION(dev),
1087                                             drv->of_match_table);
1088
1089         return !!__acpi_match_device(acpi_companion_match(dev),
1090                                      drv->acpi_match_table, drv->of_match_table);
1091 }
1092 EXPORT_SYMBOL_GPL(acpi_driver_match_device);
1093
1094 static void acpi_free_power_resources_lists(struct acpi_device *device)
1095 {
1096         int i;
1097
1098         if (device->wakeup.flags.valid)
1099                 acpi_power_resources_list_free(&device->wakeup.resources);
1100
1101         if (!device->power.flags.power_resources)
1102                 return;
1103
1104         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
1105                 struct acpi_device_power_state *ps = &device->power.states[i];
1106                 acpi_power_resources_list_free(&ps->resources);
1107         }
1108 }
1109
1110 static void acpi_device_release(struct device *dev)
1111 {
1112         struct acpi_device *acpi_dev = to_acpi_device(dev);
1113
1114         acpi_free_properties(acpi_dev);
1115         acpi_free_pnp_ids(&acpi_dev->pnp);
1116         acpi_free_power_resources_lists(acpi_dev);
1117         kfree(acpi_dev);
1118 }
1119
1120 static int acpi_bus_match(struct device *dev, struct device_driver *drv)
1121 {
1122         struct acpi_device *acpi_dev = to_acpi_device(dev);
1123         struct acpi_driver *acpi_drv = to_acpi_driver(drv);
1124
1125         return acpi_dev->flags.match_driver
1126                 && !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
1127 }
1128
1129 static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
1130 {
1131         return __acpi_device_uevent_modalias(to_acpi_device(dev), env);
1132 }
1133
1134 static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
1135 {
1136         struct acpi_device *device = data;
1137
1138         device->driver->ops.notify(device, event);
1139 }
1140
1141 static void acpi_device_notify_fixed(void *data)
1142 {
1143         struct acpi_device *device = data;
1144
1145         /* Fixed hardware devices have no handles */
1146         acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
1147 }
1148
1149 static u32 acpi_device_fixed_event(void *data)
1150 {
1151         acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_device_notify_fixed, data);
1152         return ACPI_INTERRUPT_HANDLED;
1153 }
1154
1155 static int acpi_device_install_notify_handler(struct acpi_device *device)
1156 {
1157         acpi_status status;
1158
1159         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
1160                 status =
1161                     acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
1162                                                      acpi_device_fixed_event,
1163                                                      device);
1164         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
1165                 status =
1166                     acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
1167                                                      acpi_device_fixed_event,
1168                                                      device);
1169         else
1170                 status = acpi_install_notify_handler(device->handle,
1171                                                      ACPI_DEVICE_NOTIFY,
1172                                                      acpi_device_notify,
1173                                                      device);
1174
1175         if (ACPI_FAILURE(status))
1176                 return -EINVAL;
1177         return 0;
1178 }
1179
1180 static void acpi_device_remove_notify_handler(struct acpi_device *device)
1181 {
1182         if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
1183                 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
1184                                                 acpi_device_fixed_event);
1185         else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
1186                 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
1187                                                 acpi_device_fixed_event);
1188         else
1189                 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
1190                                            acpi_device_notify);
1191 }
1192
1193 static int acpi_device_probe(struct device *dev)
1194 {
1195         struct acpi_device *acpi_dev = to_acpi_device(dev);
1196         struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
1197         int ret;
1198
1199         if (acpi_dev->handler && !acpi_is_pnp_device(acpi_dev))
1200                 return -EINVAL;
1201
1202         if (!acpi_drv->ops.add)
1203                 return -ENOSYS;
1204
1205         ret = acpi_drv->ops.add(acpi_dev);
1206         if (ret)
1207                 return ret;
1208
1209         acpi_dev->driver = acpi_drv;
1210         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1211                           "Driver [%s] successfully bound to device [%s]\n",
1212                           acpi_drv->name, acpi_dev->pnp.bus_id));
1213
1214         if (acpi_drv->ops.notify) {
1215                 ret = acpi_device_install_notify_handler(acpi_dev);
1216                 if (ret) {
1217                         if (acpi_drv->ops.remove)
1218                                 acpi_drv->ops.remove(acpi_dev);
1219
1220                         acpi_dev->driver = NULL;
1221                         acpi_dev->driver_data = NULL;
1222                         return ret;
1223                 }
1224         }
1225
1226         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found driver [%s] for device [%s]\n",
1227                           acpi_drv->name, acpi_dev->pnp.bus_id));
1228         get_device(dev);
1229         return 0;
1230 }
1231
1232 static int acpi_device_remove(struct device * dev)
1233 {
1234         struct acpi_device *acpi_dev = to_acpi_device(dev);
1235         struct acpi_driver *acpi_drv = acpi_dev->driver;
1236
1237         if (acpi_drv) {
1238                 if (acpi_drv->ops.notify)
1239                         acpi_device_remove_notify_handler(acpi_dev);
1240                 if (acpi_drv->ops.remove)
1241                         acpi_drv->ops.remove(acpi_dev);
1242         }
1243         acpi_dev->driver = NULL;
1244         acpi_dev->driver_data = NULL;
1245
1246         put_device(dev);
1247         return 0;
1248 }
1249
1250 struct bus_type acpi_bus_type = {
1251         .name           = "acpi",
1252         .match          = acpi_bus_match,
1253         .probe          = acpi_device_probe,
1254         .remove         = acpi_device_remove,
1255         .uevent         = acpi_device_uevent,
1256 };
1257
1258 static void acpi_device_del(struct acpi_device *device)
1259 {
1260         mutex_lock(&acpi_device_lock);
1261         if (device->parent)
1262                 list_del(&device->node);
1263
1264         list_del(&device->wakeup_list);
1265         mutex_unlock(&acpi_device_lock);
1266
1267         acpi_power_add_remove_device(device, false);
1268         acpi_device_remove_files(device);
1269         if (device->remove)
1270                 device->remove(device);
1271
1272         device_del(&device->dev);
1273 }
1274
1275 static LIST_HEAD(acpi_device_del_list);
1276 static DEFINE_MUTEX(acpi_device_del_lock);
1277
1278 static void acpi_device_del_work_fn(struct work_struct *work_not_used)
1279 {
1280         for (;;) {
1281                 struct acpi_device *adev;
1282
1283                 mutex_lock(&acpi_device_del_lock);
1284
1285                 if (list_empty(&acpi_device_del_list)) {
1286                         mutex_unlock(&acpi_device_del_lock);
1287                         break;
1288                 }
1289                 adev = list_first_entry(&acpi_device_del_list,
1290                                         struct acpi_device, del_list);
1291                 list_del(&adev->del_list);
1292
1293                 mutex_unlock(&acpi_device_del_lock);
1294
1295                 acpi_device_del(adev);
1296                 /*
1297                  * Drop references to all power resources that might have been
1298                  * used by the device.
1299                  */
1300                 acpi_power_transition(adev, ACPI_STATE_D3_COLD);
1301                 put_device(&adev->dev);
1302         }
1303 }
1304
1305 /**
1306  * acpi_scan_drop_device - Drop an ACPI device object.
1307  * @handle: Handle of an ACPI namespace node, not used.
1308  * @context: Address of the ACPI device object to drop.
1309  *
1310  * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
1311  * namespace node the device object pointed to by @context is attached to.
1312  *
1313  * The unregistration is carried out asynchronously to avoid running
1314  * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
1315  * ensure the correct ordering (the device objects must be unregistered in the
1316  * same order in which the corresponding namespace nodes are deleted).
1317  */
1318 static void acpi_scan_drop_device(acpi_handle handle, void *context)
1319 {
1320         static DECLARE_WORK(work, acpi_device_del_work_fn);
1321         struct acpi_device *adev = context;
1322
1323         mutex_lock(&acpi_device_del_lock);
1324
1325         /*
1326          * Use the ACPI hotplug workqueue which is ordered, so this work item
1327          * won't run after any hotplug work items submitted subsequently.  That
1328          * prevents attempts to register device objects identical to those being
1329          * deleted from happening concurrently (such attempts result from
1330          * hotplug events handled via the ACPI hotplug workqueue).  It also will
1331          * run after all of the work items submitted previosuly, which helps
1332          * those work items to ensure that they are not accessing stale device
1333          * objects.
1334          */
1335         if (list_empty(&acpi_device_del_list))
1336                 acpi_queue_hotplug_work(&work);
1337
1338         list_add_tail(&adev->del_list, &acpi_device_del_list);
1339         /* Make acpi_ns_validate_handle() return NULL for this handle. */
1340         adev->handle = INVALID_ACPI_HANDLE;
1341
1342         mutex_unlock(&acpi_device_del_lock);
1343 }
1344
1345 static int acpi_get_device_data(acpi_handle handle, struct acpi_device **device,
1346                                 void (*callback)(void *))
1347 {
1348         acpi_status status;
1349
1350         if (!device)
1351                 return -EINVAL;
1352
1353         status = acpi_get_data_full(handle, acpi_scan_drop_device,
1354                                     (void **)device, callback);
1355         if (ACPI_FAILURE(status) || !*device) {
1356                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
1357                                   handle));
1358                 return -ENODEV;
1359         }
1360         return 0;
1361 }
1362
1363 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
1364 {
1365         return acpi_get_device_data(handle, device, NULL);
1366 }
1367 EXPORT_SYMBOL(acpi_bus_get_device);
1368
1369 static void get_acpi_device(void *dev)
1370 {
1371         if (dev)
1372                 get_device(&((struct acpi_device *)dev)->dev);
1373 }
1374
1375 struct acpi_device *acpi_bus_get_acpi_device(acpi_handle handle)
1376 {
1377         struct acpi_device *adev = NULL;
1378
1379         acpi_get_device_data(handle, &adev, get_acpi_device);
1380         return adev;
1381 }
1382
1383 void acpi_bus_put_acpi_device(struct acpi_device *adev)
1384 {
1385         put_device(&adev->dev);
1386 }
1387
1388 int acpi_device_add(struct acpi_device *device,
1389                     void (*release)(struct device *))
1390 {
1391         int result;
1392         struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
1393         int found = 0;
1394
1395         if (device->handle) {
1396                 acpi_status status;
1397
1398                 status = acpi_attach_data(device->handle, acpi_scan_drop_device,
1399                                           device);
1400                 if (ACPI_FAILURE(status)) {
1401                         acpi_handle_err(device->handle,
1402                                         "Unable to attach device data\n");
1403                         return -ENODEV;
1404                 }
1405         }
1406
1407         /*
1408          * Linkage
1409          * -------
1410          * Link this device to its parent and siblings.
1411          */
1412         INIT_LIST_HEAD(&device->children);
1413         INIT_LIST_HEAD(&device->node);
1414         INIT_LIST_HEAD(&device->wakeup_list);
1415         INIT_LIST_HEAD(&device->physical_node_list);
1416         INIT_LIST_HEAD(&device->del_list);
1417         mutex_init(&device->physical_node_lock);
1418
1419         new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
1420         if (!new_bus_id) {
1421                 pr_err(PREFIX "Memory allocation error\n");
1422                 result = -ENOMEM;
1423                 goto err_detach;
1424         }
1425
1426         mutex_lock(&acpi_device_lock);
1427         /*
1428          * Find suitable bus_id and instance number in acpi_bus_id_list
1429          * If failed, create one and link it into acpi_bus_id_list
1430          */
1431         list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
1432                 if (!strcmp(acpi_device_bus_id->bus_id,
1433                             acpi_device_hid(device))) {
1434                         acpi_device_bus_id->instance_no++;
1435                         found = 1;
1436                         kfree(new_bus_id);
1437                         break;
1438                 }
1439         }
1440         if (!found) {
1441                 acpi_device_bus_id = new_bus_id;
1442                 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
1443                 acpi_device_bus_id->instance_no = 0;
1444                 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
1445         }
1446         dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
1447
1448         if (device->parent)
1449                 list_add_tail(&device->node, &device->parent->children);
1450
1451         if (device->wakeup.flags.valid)
1452                 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
1453         mutex_unlock(&acpi_device_lock);
1454
1455         if (device->parent)
1456                 device->dev.parent = &device->parent->dev;
1457         device->dev.bus = &acpi_bus_type;
1458         device->dev.release = release;
1459         result = device_add(&device->dev);
1460         if (result) {
1461                 dev_err(&device->dev, "Error registering device\n");
1462                 goto err;
1463         }
1464
1465         result = acpi_device_setup_files(device);
1466         if (result)
1467                 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
1468                        dev_name(&device->dev));
1469
1470         return 0;
1471
1472  err:
1473         mutex_lock(&acpi_device_lock);
1474         if (device->parent)
1475                 list_del(&device->node);
1476         list_del(&device->wakeup_list);
1477         mutex_unlock(&acpi_device_lock);
1478
1479  err_detach:
1480         acpi_detach_data(device->handle, acpi_scan_drop_device);
1481         return result;
1482 }
1483
1484 struct acpi_device *acpi_get_next_child(struct device *dev,
1485                                         struct acpi_device *child)
1486 {
1487         struct acpi_device *adev = ACPI_COMPANION(dev);
1488         struct list_head *head, *next;
1489
1490         if (!adev)
1491                 return NULL;
1492
1493         head = &adev->children;
1494         if (list_empty(head))
1495                 return NULL;
1496
1497         if (!child)
1498                 return list_first_entry(head, struct acpi_device, node);
1499
1500         next = child->node.next;
1501         return next == head ? NULL : list_entry(next, struct acpi_device, node);
1502 }
1503
1504 /* --------------------------------------------------------------------------
1505                                  Driver Management
1506    -------------------------------------------------------------------------- */
1507 /**
1508  * acpi_bus_register_driver - register a driver with the ACPI bus
1509  * @driver: driver being registered
1510  *
1511  * Registers a driver with the ACPI bus.  Searches the namespace for all
1512  * devices that match the driver's criteria and binds.  Returns zero for
1513  * success or a negative error status for failure.
1514  */
1515 int acpi_bus_register_driver(struct acpi_driver *driver)
1516 {
1517         int ret;
1518
1519         if (acpi_disabled)
1520                 return -ENODEV;
1521         driver->drv.name = driver->name;
1522         driver->drv.bus = &acpi_bus_type;
1523         driver->drv.owner = driver->owner;
1524
1525         ret = driver_register(&driver->drv);
1526         return ret;
1527 }
1528
1529 EXPORT_SYMBOL(acpi_bus_register_driver);
1530
1531 /**
1532  * acpi_bus_unregister_driver - unregisters a driver with the ACPI bus
1533  * @driver: driver to unregister
1534  *
1535  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
1536  * devices that match the driver's criteria and unbinds.
1537  */
1538 void acpi_bus_unregister_driver(struct acpi_driver *driver)
1539 {
1540         driver_unregister(&driver->drv);
1541 }
1542
1543 EXPORT_SYMBOL(acpi_bus_unregister_driver);
1544
1545 /* --------------------------------------------------------------------------
1546                                  Device Enumeration
1547    -------------------------------------------------------------------------- */
1548 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
1549 {
1550         struct acpi_device *device = NULL;
1551         acpi_status status;
1552
1553         /*
1554          * Fixed hardware devices do not appear in the namespace and do not
1555          * have handles, but we fabricate acpi_devices for them, so we have
1556          * to deal with them specially.
1557          */
1558         if (!handle)
1559                 return acpi_root;
1560
1561         do {
1562                 status = acpi_get_parent(handle, &handle);
1563                 if (ACPI_FAILURE(status))
1564                         return status == AE_NULL_ENTRY ? NULL : acpi_root;
1565         } while (acpi_bus_get_device(handle, &device));
1566         return device;
1567 }
1568
1569 acpi_status
1570 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
1571 {
1572         acpi_status status;
1573         acpi_handle tmp;
1574         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
1575         union acpi_object *obj;
1576
1577         status = acpi_get_handle(handle, "_EJD", &tmp);
1578         if (ACPI_FAILURE(status))
1579                 return status;
1580
1581         status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
1582         if (ACPI_SUCCESS(status)) {
1583                 obj = buffer.pointer;
1584                 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
1585                                          ejd);
1586                 kfree(buffer.pointer);
1587         }
1588         return status;
1589 }
1590 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
1591
1592 static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
1593                                         struct acpi_device_wakeup *wakeup)
1594 {
1595         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1596         union acpi_object *package = NULL;
1597         union acpi_object *element = NULL;
1598         acpi_status status;
1599         int err = -ENODATA;
1600
1601         if (!wakeup)
1602                 return -EINVAL;
1603
1604         INIT_LIST_HEAD(&wakeup->resources);
1605
1606         /* _PRW */
1607         status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
1608         if (ACPI_FAILURE(status)) {
1609                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
1610                 return err;
1611         }
1612
1613         package = (union acpi_object *)buffer.pointer;
1614
1615         if (!package || package->package.count < 2)
1616                 goto out;
1617
1618         element = &(package->package.elements[0]);
1619         if (!element)
1620                 goto out;
1621
1622         if (element->type == ACPI_TYPE_PACKAGE) {
1623                 if ((element->package.count < 2) ||
1624                     (element->package.elements[0].type !=
1625                      ACPI_TYPE_LOCAL_REFERENCE)
1626                     || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
1627                         goto out;
1628
1629                 wakeup->gpe_device =
1630                     element->package.elements[0].reference.handle;
1631                 wakeup->gpe_number =
1632                     (u32) element->package.elements[1].integer.value;
1633         } else if (element->type == ACPI_TYPE_INTEGER) {
1634                 wakeup->gpe_device = NULL;
1635                 wakeup->gpe_number = element->integer.value;
1636         } else {
1637                 goto out;
1638         }
1639
1640         element = &(package->package.elements[1]);
1641         if (element->type != ACPI_TYPE_INTEGER)
1642                 goto out;
1643
1644         wakeup->sleep_state = element->integer.value;
1645
1646         err = acpi_extract_power_resources(package, 2, &wakeup->resources);
1647         if (err)
1648                 goto out;
1649
1650         if (!list_empty(&wakeup->resources)) {
1651                 int sleep_state;
1652
1653                 err = acpi_power_wakeup_list_init(&wakeup->resources,
1654                                                   &sleep_state);
1655                 if (err) {
1656                         acpi_handle_warn(handle, "Retrieving current states "
1657                                          "of wakeup power resources failed\n");
1658                         acpi_power_resources_list_free(&wakeup->resources);
1659                         goto out;
1660                 }
1661                 if (sleep_state < wakeup->sleep_state) {
1662                         acpi_handle_warn(handle, "Overriding _PRW sleep state "
1663                                          "(S%d) by S%d from power resources\n",
1664                                          (int)wakeup->sleep_state, sleep_state);
1665                         wakeup->sleep_state = sleep_state;
1666                 }
1667         }
1668
1669  out:
1670         kfree(buffer.pointer);
1671         return err;
1672 }
1673
1674 static void acpi_wakeup_gpe_init(struct acpi_device *device)
1675 {
1676         static const struct acpi_device_id button_device_ids[] = {
1677                 {"PNP0C0C", 0},
1678                 {"PNP0C0D", 0},
1679                 {"PNP0C0E", 0},
1680                 {"", 0},
1681         };
1682         struct acpi_device_wakeup *wakeup = &device->wakeup;
1683         acpi_status status;
1684         acpi_event_status event_status;
1685
1686         wakeup->flags.notifier_present = 0;
1687
1688         /* Power button, Lid switch always enable wakeup */
1689         if (!acpi_match_device_ids(device, button_device_ids)) {
1690                 wakeup->flags.run_wake = 1;
1691                 if (!acpi_match_device_ids(device, &button_device_ids[1])) {
1692                         /* Do not use Lid/sleep button for S5 wakeup */
1693                         if (wakeup->sleep_state == ACPI_STATE_S5)
1694                                 wakeup->sleep_state = ACPI_STATE_S4;
1695                 }
1696                 acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
1697                 device_set_wakeup_capable(&device->dev, true);
1698                 return;
1699         }
1700
1701         acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
1702                                 wakeup->gpe_number);
1703         status = acpi_get_gpe_status(wakeup->gpe_device, wakeup->gpe_number,
1704                                      &event_status);
1705         if (ACPI_FAILURE(status))
1706                 return;
1707
1708         wakeup->flags.run_wake = !!(event_status & ACPI_EVENT_FLAG_HAS_HANDLER);
1709 }
1710
1711 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
1712 {
1713         int err;
1714
1715         /* Presence of _PRW indicates wake capable */
1716         if (!acpi_has_method(device->handle, "_PRW"))
1717                 return;
1718
1719         err = acpi_bus_extract_wakeup_device_power_package(device->handle,
1720                                                            &device->wakeup);
1721         if (err) {
1722                 dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
1723                 return;
1724         }
1725
1726         device->wakeup.flags.valid = 1;
1727         device->wakeup.prepare_count = 0;
1728         acpi_wakeup_gpe_init(device);
1729         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
1730          * system for the ACPI device with the _PRW object.
1731          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
1732          * So it is necessary to call _DSW object first. Only when it is not
1733          * present will the _PSW object used.
1734          */
1735         err = acpi_device_sleep_wake(device, 0, 0, 0);
1736         if (err)
1737                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1738                                 "error in _DSW or _PSW evaluation\n"));
1739 }
1740
1741 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
1742 {
1743         struct acpi_device_power_state *ps = &device->power.states[state];
1744         char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
1745         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1746         acpi_status status;
1747
1748         INIT_LIST_HEAD(&ps->resources);
1749
1750         /* Evaluate "_PRx" to get referenced power resources */
1751         status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
1752         if (ACPI_SUCCESS(status)) {
1753                 union acpi_object *package = buffer.pointer;
1754
1755                 if (buffer.length && package
1756                     && package->type == ACPI_TYPE_PACKAGE
1757                     && package->package.count) {
1758                         int err = acpi_extract_power_resources(package, 0,
1759                                                                &ps->resources);
1760                         if (!err)
1761                                 device->power.flags.power_resources = 1;
1762                 }
1763                 ACPI_FREE(buffer.pointer);
1764         }
1765
1766         /* Evaluate "_PSx" to see if we can do explicit sets */
1767         pathname[2] = 'S';
1768         if (acpi_has_method(device->handle, pathname))
1769                 ps->flags.explicit_set = 1;
1770
1771         /* State is valid if there are means to put the device into it. */
1772         if (!list_empty(&ps->resources) || ps->flags.explicit_set)
1773                 ps->flags.valid = 1;
1774
1775         ps->power = -1;         /* Unknown - driver assigned */
1776         ps->latency = -1;       /* Unknown - driver assigned */
1777 }
1778
1779 static void acpi_bus_get_power_flags(struct acpi_device *device)
1780 {
1781         u32 i;
1782
1783         /* Presence of _PS0|_PR0 indicates 'power manageable' */
1784         if (!acpi_has_method(device->handle, "_PS0") &&
1785             !acpi_has_method(device->handle, "_PR0"))
1786                 return;
1787
1788         device->flags.power_manageable = 1;
1789
1790         /*
1791          * Power Management Flags
1792          */
1793         if (acpi_has_method(device->handle, "_PSC"))
1794                 device->power.flags.explicit_get = 1;
1795
1796         if (acpi_has_method(device->handle, "_IRC"))
1797                 device->power.flags.inrush_current = 1;
1798
1799         if (acpi_has_method(device->handle, "_DSW"))
1800                 device->power.flags.dsw_present = 1;
1801
1802         /*
1803          * Enumerate supported power management states
1804          */
1805         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
1806                 acpi_bus_init_power_state(device, i);
1807
1808         INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
1809         if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources))
1810                 device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
1811
1812         /* Set defaults for D0 and D3hot states (always valid) */
1813         device->power.states[ACPI_STATE_D0].flags.valid = 1;
1814         device->power.states[ACPI_STATE_D0].power = 100;
1815         device->power.states[ACPI_STATE_D3_HOT].flags.valid = 1;
1816
1817         if (acpi_bus_init_power(device))
1818                 device->flags.power_manageable = 0;
1819 }
1820
1821 static void acpi_bus_get_flags(struct acpi_device *device)
1822 {
1823         /* Presence of _STA indicates 'dynamic_status' */
1824         if (acpi_has_method(device->handle, "_STA"))
1825                 device->flags.dynamic_status = 1;
1826
1827         /* Presence of _RMV indicates 'removable' */
1828         if (acpi_has_method(device->handle, "_RMV"))
1829                 device->flags.removable = 1;
1830
1831         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
1832         if (acpi_has_method(device->handle, "_EJD") ||
1833             acpi_has_method(device->handle, "_EJ0"))
1834                 device->flags.ejectable = 1;
1835 }
1836
1837 static void acpi_device_get_busid(struct acpi_device *device)
1838 {
1839         char bus_id[5] = { '?', 0 };
1840         struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1841         int i = 0;
1842
1843         /*
1844          * Bus ID
1845          * ------
1846          * The device's Bus ID is simply the object name.
1847          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1848          */
1849         if (ACPI_IS_ROOT_DEVICE(device)) {
1850                 strcpy(device->pnp.bus_id, "ACPI");
1851                 return;
1852         }
1853
1854         switch (device->device_type) {
1855         case ACPI_BUS_TYPE_POWER_BUTTON:
1856                 strcpy(device->pnp.bus_id, "PWRF");
1857                 break;
1858         case ACPI_BUS_TYPE_SLEEP_BUTTON:
1859                 strcpy(device->pnp.bus_id, "SLPF");
1860                 break;
1861         default:
1862                 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1863                 /* Clean up trailing underscores (if any) */
1864                 for (i = 3; i > 1; i--) {
1865                         if (bus_id[i] == '_')
1866                                 bus_id[i] = '\0';
1867                         else
1868                                 break;
1869                 }
1870                 strcpy(device->pnp.bus_id, bus_id);
1871                 break;
1872         }
1873 }
1874
1875 /*
1876  * acpi_ata_match - see if an acpi object is an ATA device
1877  *
1878  * If an acpi object has one of the ACPI ATA methods defined,
1879  * then we can safely call it an ATA device.
1880  */
1881 bool acpi_ata_match(acpi_handle handle)
1882 {
1883         return acpi_has_method(handle, "_GTF") ||
1884                acpi_has_method(handle, "_GTM") ||
1885                acpi_has_method(handle, "_STM") ||
1886                acpi_has_method(handle, "_SDD");
1887 }
1888
1889 /*
1890  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1891  *
1892  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1893  * then we can safely call it an ejectable drive bay
1894  */
1895 bool acpi_bay_match(acpi_handle handle)
1896 {
1897         acpi_handle phandle;
1898
1899         if (!acpi_has_method(handle, "_EJ0"))
1900                 return false;
1901         if (acpi_ata_match(handle))
1902                 return true;
1903         if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1904                 return false;
1905
1906         return acpi_ata_match(phandle);
1907 }
1908
1909 bool acpi_device_is_battery(struct acpi_device *adev)
1910 {
1911         struct acpi_hardware_id *hwid;
1912
1913         list_for_each_entry(hwid, &adev->pnp.ids, list)
1914                 if (!strcmp("PNP0C0A", hwid->id))
1915                         return true;
1916
1917         return false;
1918 }
1919
1920 static bool is_ejectable_bay(struct acpi_device *adev)
1921 {
1922         acpi_handle handle = adev->handle;
1923
1924         if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
1925                 return true;
1926
1927         return acpi_bay_match(handle);
1928 }
1929
1930 /*
1931  * acpi_dock_match - see if an acpi object has a _DCK method
1932  */
1933 bool acpi_dock_match(acpi_handle handle)
1934 {
1935         return acpi_has_method(handle, "_DCK");
1936 }
1937
1938 static acpi_status
1939 acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
1940                           void **return_value)
1941 {
1942         long *cap = context;
1943
1944         if (acpi_has_method(handle, "_BCM") &&
1945             acpi_has_method(handle, "_BCL")) {
1946                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight "
1947                                   "support\n"));
1948                 *cap |= ACPI_VIDEO_BACKLIGHT;
1949                 if (!acpi_has_method(handle, "_BQC"))
1950                         printk(KERN_WARNING FW_BUG PREFIX "No _BQC method, "
1951                                 "cannot determine initial brightness\n");
1952                 /* We have backlight support, no need to scan further */
1953                 return AE_CTRL_TERMINATE;
1954         }
1955         return 0;
1956 }
1957
1958 /* Returns true if the ACPI object is a video device which can be
1959  * handled by video.ko.
1960  * The device will get a Linux specific CID added in scan.c to
1961  * identify the device as an ACPI graphics device
1962  * Be aware that the graphics device may not be physically present
1963  * Use acpi_video_get_capabilities() to detect general ACPI video
1964  * capabilities of present cards
1965  */
1966 long acpi_is_video_device(acpi_handle handle)
1967 {
1968         long video_caps = 0;
1969
1970         /* Is this device able to support video switching ? */
1971         if (acpi_has_method(handle, "_DOD") || acpi_has_method(handle, "_DOS"))
1972                 video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
1973
1974         /* Is this device able to retrieve a video ROM ? */
1975         if (acpi_has_method(handle, "_ROM"))
1976                 video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
1977
1978         /* Is this device able to configure which video head to be POSTed ? */
1979         if (acpi_has_method(handle, "_VPO") &&
1980             acpi_has_method(handle, "_GPD") &&
1981             acpi_has_method(handle, "_SPD"))
1982                 video_caps |= ACPI_VIDEO_DEVICE_POSTING;
1983
1984         /* Only check for backlight functionality if one of the above hit. */
1985         if (video_caps)
1986                 acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
1987                                     ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
1988                                     &video_caps, NULL);
1989
1990         return video_caps;
1991 }
1992 EXPORT_SYMBOL(acpi_is_video_device);
1993
1994 const char *acpi_device_hid(struct acpi_device *device)
1995 {
1996         struct acpi_hardware_id *hid;
1997
1998         if (list_empty(&device->pnp.ids))
1999                 return dummy_hid;
2000
2001         hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
2002         return hid->id;
2003 }
2004 EXPORT_SYMBOL(acpi_device_hid);
2005
2006 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
2007 {
2008         struct acpi_hardware_id *id;
2009
2010         id = kmalloc(sizeof(*id), GFP_KERNEL);
2011         if (!id)
2012                 return;
2013
2014         id->id = kstrdup(dev_id, GFP_KERNEL);
2015         if (!id->id) {
2016                 kfree(id);
2017                 return;
2018         }
2019
2020         list_add_tail(&id->list, &pnp->ids);
2021         pnp->type.hardware_id = 1;
2022 }
2023
2024 /*
2025  * Old IBM workstations have a DSDT bug wherein the SMBus object
2026  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
2027  * prefix.  Work around this.
2028  */
2029 static bool acpi_ibm_smbus_match(acpi_handle handle)
2030 {
2031         char node_name[ACPI_PATH_SEGMENT_LENGTH];
2032         struct acpi_buffer path = { sizeof(node_name), node_name };
2033
2034         if (!dmi_name_in_vendors("IBM"))
2035                 return false;
2036
2037         /* Look for SMBS object */
2038         if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
2039             strcmp("SMBS", path.pointer))
2040                 return false;
2041
2042         /* Does it have the necessary (but misnamed) methods? */
2043         if (acpi_has_method(handle, "SBI") &&
2044             acpi_has_method(handle, "SBR") &&
2045             acpi_has_method(handle, "SBW"))
2046                 return true;
2047
2048         return false;
2049 }
2050
2051 static bool acpi_object_is_system_bus(acpi_handle handle)
2052 {
2053         acpi_handle tmp;
2054
2055         if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
2056             tmp == handle)
2057                 return true;
2058         if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
2059             tmp == handle)
2060                 return true;
2061
2062         return false;
2063 }
2064
2065 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
2066                                 int device_type)
2067 {
2068         acpi_status status;
2069         struct acpi_device_info *info;
2070         struct acpi_pnp_device_id_list *cid_list;
2071         int i;
2072
2073         switch (device_type) {
2074         case ACPI_BUS_TYPE_DEVICE:
2075                 if (handle == ACPI_ROOT_OBJECT) {
2076                         acpi_add_id(pnp, ACPI_SYSTEM_HID);
2077                         break;
2078                 }
2079
2080                 status = acpi_get_object_info(handle, &info);
2081                 if (ACPI_FAILURE(status)) {
2082                         pr_err(PREFIX "%s: Error reading device info\n",
2083                                         __func__);
2084                         return;
2085                 }
2086
2087                 if (info->valid & ACPI_VALID_HID) {
2088                         acpi_add_id(pnp, info->hardware_id.string);
2089                         pnp->type.platform_id = 1;
2090                 }
2091                 if (info->valid & ACPI_VALID_CID) {
2092                         cid_list = &info->compatible_id_list;
2093                         for (i = 0; i < cid_list->count; i++)
2094                                 acpi_add_id(pnp, cid_list->ids[i].string);
2095                 }
2096                 if (info->valid & ACPI_VALID_ADR) {
2097                         pnp->bus_address = info->address;
2098                         pnp->type.bus_address = 1;
2099                 }
2100                 if (info->valid & ACPI_VALID_UID)
2101                         pnp->unique_id = kstrdup(info->unique_id.string,
2102                                                         GFP_KERNEL);
2103
2104                 kfree(info);
2105
2106                 /*
2107                  * Some devices don't reliably have _HIDs & _CIDs, so add
2108                  * synthetic HIDs to make sure drivers can find them.
2109                  */
2110                 if (acpi_is_video_device(handle))
2111                         acpi_add_id(pnp, ACPI_VIDEO_HID);
2112                 else if (acpi_bay_match(handle))
2113                         acpi_add_id(pnp, ACPI_BAY_HID);
2114                 else if (acpi_dock_match(handle))
2115                         acpi_add_id(pnp, ACPI_DOCK_HID);
2116                 else if (acpi_ibm_smbus_match(handle))
2117                         acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
2118                 else if (list_empty(&pnp->ids) &&
2119                          acpi_object_is_system_bus(handle)) {
2120                         /* \_SB, \_TZ, LNXSYBUS */
2121                         acpi_add_id(pnp, ACPI_BUS_HID);
2122                         strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
2123                         strcpy(pnp->device_class, ACPI_BUS_CLASS);
2124                 }
2125
2126                 break;
2127         case ACPI_BUS_TYPE_POWER:
2128                 acpi_add_id(pnp, ACPI_POWER_HID);
2129                 break;
2130         case ACPI_BUS_TYPE_PROCESSOR:
2131                 acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
2132                 break;
2133         case ACPI_BUS_TYPE_THERMAL:
2134                 acpi_add_id(pnp, ACPI_THERMAL_HID);
2135                 break;
2136         case ACPI_BUS_TYPE_POWER_BUTTON:
2137                 acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
2138                 break;
2139         case ACPI_BUS_TYPE_SLEEP_BUTTON:
2140                 acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
2141                 break;
2142         }
2143 }
2144
2145 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
2146 {
2147         struct acpi_hardware_id *id, *tmp;
2148
2149         list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
2150                 kfree(id->id);
2151                 kfree(id);
2152         }
2153         kfree(pnp->unique_id);
2154 }
2155
2156 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
2157                              int type, unsigned long long sta)
2158 {
2159         INIT_LIST_HEAD(&device->pnp.ids);
2160         device->device_type = type;
2161         device->handle = handle;
2162         device->parent = acpi_bus_get_parent(handle);
2163         device->fwnode.type = FWNODE_ACPI;
2164         acpi_set_device_status(device, sta);
2165         acpi_device_get_busid(device);
2166         acpi_set_pnp_ids(handle, &device->pnp, type);
2167         acpi_init_properties(device);
2168         acpi_bus_get_flags(device);
2169         device->flags.match_driver = false;
2170         device->flags.initialized = true;
2171         device->flags.visited = false;
2172         device_initialize(&device->dev);
2173         dev_set_uevent_suppress(&device->dev, true);
2174 }
2175
2176 void acpi_device_add_finalize(struct acpi_device *device)
2177 {
2178         dev_set_uevent_suppress(&device->dev, false);
2179         kobject_uevent(&device->dev.kobj, KOBJ_ADD);
2180 }
2181
2182 static int acpi_add_single_object(struct acpi_device **child,
2183                                   acpi_handle handle, int type,
2184                                   unsigned long long sta)
2185 {
2186         int result;
2187         struct acpi_device *device;
2188         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
2189
2190         device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
2191         if (!device) {
2192                 printk(KERN_ERR PREFIX "Memory allocation error\n");
2193                 return -ENOMEM;
2194         }
2195
2196         acpi_init_device_object(device, handle, type, sta);
2197         acpi_bus_get_power_flags(device);
2198         acpi_bus_get_wakeup_device_flags(device);
2199
2200         result = acpi_device_add(device, acpi_device_release);
2201         if (result) {
2202                 acpi_device_release(&device->dev);
2203                 return result;
2204         }
2205
2206         acpi_power_add_remove_device(device, true);
2207         acpi_device_add_finalize(device);
2208         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
2209         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
2210                 dev_name(&device->dev), (char *) buffer.pointer,
2211                 device->parent ? dev_name(&device->parent->dev) : "(null)"));
2212         kfree(buffer.pointer);
2213         *child = device;
2214         return 0;
2215 }
2216
2217 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
2218                                     unsigned long long *sta)
2219 {
2220         acpi_status status;
2221         acpi_object_type acpi_type;
2222
2223         status = acpi_get_type(handle, &acpi_type);
2224         if (ACPI_FAILURE(status))
2225                 return -ENODEV;
2226
2227         switch (acpi_type) {
2228         case ACPI_TYPE_ANY:             /* for ACPI_ROOT_OBJECT */
2229         case ACPI_TYPE_DEVICE:
2230                 *type = ACPI_BUS_TYPE_DEVICE;
2231                 status = acpi_bus_get_status_handle(handle, sta);
2232                 if (ACPI_FAILURE(status))
2233                         return -ENODEV;
2234                 break;
2235         case ACPI_TYPE_PROCESSOR:
2236                 *type = ACPI_BUS_TYPE_PROCESSOR;
2237                 status = acpi_bus_get_status_handle(handle, sta);
2238                 if (ACPI_FAILURE(status))
2239                         return -ENODEV;
2240                 break;
2241         case ACPI_TYPE_THERMAL:
2242                 *type = ACPI_BUS_TYPE_THERMAL;
2243                 *sta = ACPI_STA_DEFAULT;
2244                 break;
2245         case ACPI_TYPE_POWER:
2246                 *type = ACPI_BUS_TYPE_POWER;
2247                 *sta = ACPI_STA_DEFAULT;
2248                 break;
2249         default:
2250                 return -ENODEV;
2251         }
2252
2253         return 0;
2254 }
2255
2256 bool acpi_device_is_present(struct acpi_device *adev)
2257 {
2258         if (adev->status.present || adev->status.functional)
2259                 return true;
2260
2261         adev->flags.initialized = false;
2262         return false;
2263 }
2264
2265 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
2266                                        char *idstr,
2267                                        const struct acpi_device_id **matchid)
2268 {
2269         const struct acpi_device_id *devid;
2270
2271         if (handler->match)
2272                 return handler->match(idstr, matchid);
2273
2274         for (devid = handler->ids; devid->id[0]; devid++)
2275                 if (!strcmp((char *)devid->id, idstr)) {
2276                         if (matchid)
2277                                 *matchid = devid;
2278
2279                         return true;
2280                 }
2281
2282         return false;
2283 }
2284
2285 static struct acpi_scan_handler *acpi_scan_match_handler(char *idstr,
2286                                         const struct acpi_device_id **matchid)
2287 {
2288         struct acpi_scan_handler *handler;
2289
2290         list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
2291                 if (acpi_scan_handler_matching(handler, idstr, matchid))
2292                         return handler;
2293
2294         return NULL;
2295 }
2296
2297 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
2298 {
2299         if (!!hotplug->enabled == !!val)
2300                 return;
2301
2302         mutex_lock(&acpi_scan_lock);
2303
2304         hotplug->enabled = val;
2305
2306         mutex_unlock(&acpi_scan_lock);
2307 }
2308
2309 static void acpi_scan_init_hotplug(struct acpi_device *adev)
2310 {
2311         struct acpi_hardware_id *hwid;
2312
2313         if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
2314                 acpi_dock_add(adev);
2315                 return;
2316         }
2317         list_for_each_entry(hwid, &adev->pnp.ids, list) {
2318                 struct acpi_scan_handler *handler;
2319
2320                 handler = acpi_scan_match_handler(hwid->id, NULL);
2321                 if (handler) {
2322                         adev->flags.hotplug_notify = true;
2323                         break;
2324                 }
2325         }
2326 }
2327
2328 static void acpi_device_dep_initialize(struct acpi_device *adev)
2329 {
2330         struct acpi_dep_data *dep;
2331         struct acpi_handle_list dep_devices;
2332         acpi_status status;
2333         int i;
2334
2335         if (!acpi_has_method(adev->handle, "_DEP"))
2336                 return;
2337
2338         status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
2339                                         &dep_devices);
2340         if (ACPI_FAILURE(status)) {
2341                 dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
2342                 return;
2343         }
2344
2345         for (i = 0; i < dep_devices.count; i++) {
2346                 struct acpi_device_info *info;
2347                 int skip;
2348
2349                 status = acpi_get_object_info(dep_devices.handles[i], &info);
2350                 if (ACPI_FAILURE(status)) {
2351                         dev_dbg(&adev->dev, "Error reading _DEP device info\n");
2352                         continue;
2353                 }
2354
2355                 /*
2356                  * Skip the dependency of Windows System Power
2357                  * Management Controller
2358                  */
2359                 skip = info->valid & ACPI_VALID_HID &&
2360                         !strcmp(info->hardware_id.string, "INT3396");
2361
2362                 kfree(info);
2363
2364                 if (skip)
2365                         continue;
2366
2367                 dep = kzalloc(sizeof(struct acpi_dep_data), GFP_KERNEL);
2368                 if (!dep)
2369                         return;
2370
2371                 dep->master = dep_devices.handles[i];
2372                 dep->slave  = adev->handle;
2373                 adev->dep_unmet++;
2374
2375                 mutex_lock(&acpi_dep_list_lock);
2376                 list_add_tail(&dep->node , &acpi_dep_list);
2377                 mutex_unlock(&acpi_dep_list_lock);
2378         }
2379 }
2380
2381 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
2382                                       void *not_used, void **return_value)
2383 {
2384         struct acpi_device *device = NULL;
2385         int type;
2386         unsigned long long sta;
2387         int result;
2388
2389         acpi_bus_get_device(handle, &device);
2390         if (device)
2391                 goto out;
2392
2393         result = acpi_bus_type_and_status(handle, &type, &sta);
2394         if (result)
2395                 return AE_OK;
2396
2397         if (type == ACPI_BUS_TYPE_POWER) {
2398                 acpi_add_power_resource(handle);
2399                 return AE_OK;
2400         }
2401
2402         acpi_add_single_object(&device, handle, type, sta);
2403         if (!device)
2404                 return AE_CTRL_DEPTH;
2405
2406         acpi_scan_init_hotplug(device);
2407         acpi_device_dep_initialize(device);
2408
2409  out:
2410         if (!*return_value)
2411                 *return_value = device;
2412
2413         return AE_OK;
2414 }
2415
2416 static int acpi_check_spi_i2c_slave(struct acpi_resource *ares, void *data)
2417 {
2418         bool *is_spi_i2c_slave_p = data;
2419
2420         if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
2421                 return 1;
2422
2423         /*
2424          * devices that are connected to UART still need to be enumerated to
2425          * platform bus
2426          */
2427         if (ares->data.common_serial_bus.type != ACPI_RESOURCE_SERIAL_TYPE_UART)
2428                 *is_spi_i2c_slave_p = true;
2429
2430          /* no need to do more checking */
2431         return -1;
2432 }
2433
2434 static void acpi_default_enumeration(struct acpi_device *device)
2435 {
2436         struct list_head resource_list;
2437         bool is_spi_i2c_slave = false;
2438
2439         /*
2440          * Do not enemerate SPI/I2C slaves as they will be enuerated by their
2441          * respective parents.
2442          */
2443         INIT_LIST_HEAD(&resource_list);
2444         acpi_dev_get_resources(device, &resource_list, acpi_check_spi_i2c_slave,
2445                                &is_spi_i2c_slave);
2446         acpi_dev_free_resource_list(&resource_list);
2447         if (!is_spi_i2c_slave)
2448                 acpi_create_platform_device(device);
2449 }
2450
2451 static const struct acpi_device_id generic_device_ids[] = {
2452         {ACPI_DT_NAMESPACE_HID, },
2453         {"", },
2454 };
2455
2456 static int acpi_generic_device_attach(struct acpi_device *adev,
2457                                       const struct acpi_device_id *not_used)
2458 {
2459         /*
2460          * Since ACPI_DT_NAMESPACE_HID is the only ID handled here, the test
2461          * below can be unconditional.
2462          */
2463         if (adev->data.of_compatible)
2464                 acpi_default_enumeration(adev);
2465
2466         return 1;
2467 }
2468
2469 static struct acpi_scan_handler generic_device_handler = {
2470         .ids = generic_device_ids,
2471         .attach = acpi_generic_device_attach,
2472 };
2473
2474 static int acpi_scan_attach_handler(struct acpi_device *device)
2475 {
2476         struct acpi_hardware_id *hwid;
2477         int ret = 0;
2478
2479         list_for_each_entry(hwid, &device->pnp.ids, list) {
2480                 const struct acpi_device_id *devid;
2481                 struct acpi_scan_handler *handler;
2482
2483                 handler = acpi_scan_match_handler(hwid->id, &devid);
2484                 if (handler) {
2485                         if (!handler->attach) {
2486                                 device->pnp.type.platform_id = 0;
2487                                 continue;
2488                         }
2489                         device->handler = handler;
2490                         ret = handler->attach(device, devid);
2491                         if (ret > 0)
2492                                 break;
2493
2494                         device->handler = NULL;
2495                         if (ret < 0)
2496                                 break;
2497                 }
2498         }
2499
2500         return ret;
2501 }
2502
2503 static void acpi_bus_attach(struct acpi_device *device)
2504 {
2505         struct acpi_device *child;
2506         acpi_handle ejd;
2507         int ret;
2508
2509         if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
2510                 register_dock_dependent_device(device, ejd);
2511
2512         acpi_bus_get_status(device);
2513         /* Skip devices that are not present. */
2514         if (!acpi_device_is_present(device)) {
2515                 device->flags.visited = false;
2516                 device->flags.power_manageable = 0;
2517                 return;
2518         }
2519         if (device->handler)
2520                 goto ok;
2521
2522         if (!device->flags.initialized) {
2523                 device->flags.power_manageable =
2524                         device->power.states[ACPI_STATE_D0].flags.valid;
2525                 if (acpi_bus_init_power(device))
2526                         device->flags.power_manageable = 0;
2527
2528                 device->flags.initialized = true;
2529         }
2530         device->flags.visited = false;
2531         ret = acpi_scan_attach_handler(device);
2532         if (ret < 0)
2533                 return;
2534
2535         device->flags.match_driver = true;
2536         if (!ret) {
2537                 ret = device_attach(&device->dev);
2538                 if (ret < 0)
2539                         return;
2540
2541                 if (!ret && device->pnp.type.platform_id)
2542                         acpi_default_enumeration(device);
2543         }
2544         device->flags.visited = true;
2545
2546  ok:
2547         list_for_each_entry(child, &device->children, node)
2548                 acpi_bus_attach(child);
2549
2550         if (device->handler && device->handler->hotplug.notify_online)
2551                 device->handler->hotplug.notify_online(device);
2552 }
2553
2554 void acpi_walk_dep_device_list(acpi_handle handle)
2555 {
2556         struct acpi_dep_data *dep, *tmp;
2557         struct acpi_device *adev;
2558
2559         mutex_lock(&acpi_dep_list_lock);
2560         list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
2561                 if (dep->master == handle) {
2562                         acpi_bus_get_device(dep->slave, &adev);
2563                         if (!adev)
2564                                 continue;
2565
2566                         adev->dep_unmet--;
2567                         if (!adev->dep_unmet)
2568                                 acpi_bus_attach(adev);
2569                         list_del(&dep->node);
2570                         kfree(dep);
2571                 }
2572         }
2573         mutex_unlock(&acpi_dep_list_lock);
2574 }
2575 EXPORT_SYMBOL_GPL(acpi_walk_dep_device_list);
2576
2577 /**
2578  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
2579  * @handle: Root of the namespace scope to scan.
2580  *
2581  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
2582  * found devices.
2583  *
2584  * If no devices were found, -ENODEV is returned, but it does not mean that
2585  * there has been a real error.  There just have been no suitable ACPI objects
2586  * in the table trunk from which the kernel could create a device and add an
2587  * appropriate driver.
2588  *
2589  * Must be called under acpi_scan_lock.
2590  */
2591 int acpi_bus_scan(acpi_handle handle)
2592 {
2593         void *device = NULL;
2594
2595         if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
2596                 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2597                                     acpi_bus_check_add, NULL, NULL, &device);
2598
2599         if (device) {
2600                 acpi_bus_attach(device);
2601                 return 0;
2602         }
2603         return -ENODEV;
2604 }
2605 EXPORT_SYMBOL(acpi_bus_scan);
2606
2607 /**
2608  * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
2609  * @adev: Root of the ACPI namespace scope to walk.
2610  *
2611  * Must be called under acpi_scan_lock.
2612  */
2613 void acpi_bus_trim(struct acpi_device *adev)
2614 {
2615         struct acpi_scan_handler *handler = adev->handler;
2616         struct acpi_device *child;
2617
2618         list_for_each_entry_reverse(child, &adev->children, node)
2619                 acpi_bus_trim(child);
2620
2621         adev->flags.match_driver = false;
2622         if (handler) {
2623                 if (handler->detach)
2624                         handler->detach(adev);
2625
2626                 adev->handler = NULL;
2627         } else {
2628                 device_release_driver(&adev->dev);
2629         }
2630         /*
2631          * Most likely, the device is going away, so put it into D3cold before
2632          * that.
2633          */
2634         acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
2635         adev->flags.initialized = false;
2636         adev->flags.visited = false;
2637 }
2638 EXPORT_SYMBOL_GPL(acpi_bus_trim);
2639
2640 static int acpi_bus_scan_fixed(void)
2641 {
2642         int result = 0;
2643
2644         /*
2645          * Enumerate all fixed-feature devices.
2646          */
2647         if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2648                 struct acpi_device *device = NULL;
2649
2650                 result = acpi_add_single_object(&device, NULL,
2651                                                 ACPI_BUS_TYPE_POWER_BUTTON,
2652                                                 ACPI_STA_DEFAULT);
2653                 if (result)
2654                         return result;
2655
2656                 device->flags.match_driver = true;
2657                 result = device_attach(&device->dev);
2658                 if (result < 0)
2659                         return result;
2660
2661                 device_init_wakeup(&device->dev, true);
2662         }
2663
2664         if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2665                 struct acpi_device *device = NULL;
2666
2667                 result = acpi_add_single_object(&device, NULL,
2668                                                 ACPI_BUS_TYPE_SLEEP_BUTTON,
2669                                                 ACPI_STA_DEFAULT);
2670                 if (result)
2671                         return result;
2672
2673                 device->flags.match_driver = true;
2674                 result = device_attach(&device->dev);
2675         }
2676
2677         return result < 0 ? result : 0;
2678 }
2679
2680 int __init acpi_scan_init(void)
2681 {
2682         int result;
2683
2684         result = bus_register(&acpi_bus_type);
2685         if (result) {
2686                 /* We don't want to quit even if we failed to add suspend/resume */
2687                 printk(KERN_ERR PREFIX "Could not register bus type\n");
2688         }
2689
2690         acpi_pci_root_init();
2691         acpi_pci_link_init();
2692         acpi_processor_init();
2693         acpi_lpss_init();
2694         acpi_apd_init();
2695         acpi_cmos_rtc_init();
2696         acpi_container_init();
2697         acpi_memory_hotplug_init();
2698         acpi_pnp_init();
2699         acpi_int340x_thermal_init();
2700
2701         acpi_scan_add_handler(&generic_device_handler);
2702
2703         mutex_lock(&acpi_scan_lock);
2704         /*
2705          * Enumerate devices in the ACPI namespace.
2706          */
2707         result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2708         if (result)
2709                 goto out;
2710
2711         result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2712         if (result)
2713                 goto out;
2714
2715         /* Fixed feature devices do not exist on HW-reduced platform */
2716         if (!acpi_gbl_reduced_hardware) {
2717                 result = acpi_bus_scan_fixed();
2718                 if (result) {
2719                         acpi_detach_data(acpi_root->handle,
2720                                          acpi_scan_drop_device);
2721                         acpi_device_del(acpi_root);
2722                         put_device(&acpi_root->dev);
2723                         goto out;
2724                 }
2725         }
2726
2727         acpi_update_all_gpes();
2728
2729  out:
2730         mutex_unlock(&acpi_scan_lock);
2731         return result;
2732 }