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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 #include <linux/dma-mapping.h>
15
16 #include <asm/pgtable.h>
17
18 #include "internal.h"
19
20 #define _COMPONENT ACPI_BUS_COMPONENT
21 ACPI_MODULE_NAME("scan");
22 extern struct acpi_device *acpi_root;
23
24 #define ACPI_BUS_CLASS "system_bus"
25 #define ACPI_BUS_HID "LNXSYBUS"
26 #define ACPI_BUS_DEVICE_NAME "System Bus"
27
28 #define ACPI_IS_ROOT_DEVICE(device) (!(device)->parent)
29
30 #define INVALID_ACPI_HANDLE ((acpi_handle)empty_zero_page)
31
32 /*
33 * If set, devices will be hot-removed even if they cannot be put offline
34 * gracefully (from the kernel's standpoint).
35 */
36 bool acpi_force_hot_remove;
37
38 static const char *dummy_hid = "device";
39
40 static LIST_HEAD(acpi_dep_list);
41 static DEFINE_MUTEX(acpi_dep_list_lock);
42 LIST_HEAD(acpi_bus_id_list);
43 static DEFINE_MUTEX(acpi_scan_lock);
44 static LIST_HEAD(acpi_scan_handlers_list);
45 DEFINE_MUTEX(acpi_device_lock);
46 LIST_HEAD(acpi_wakeup_device_list);
47 static DEFINE_MUTEX(acpi_hp_context_lock);
48
49 /*
50 * The UART device described by the SPCR table is the only object which needs
51 * special-casing. Everything else is covered by ACPI namespace paths in STAO
52 * table.
53 */
54 static u64 spcr_uart_addr;
55
56 struct acpi_dep_data {
57 struct list_head node;
58 acpi_handle master;
59 acpi_handle slave;
60 };
61
62 void acpi_scan_lock_acquire(void)
63 {
64 mutex_lock(&acpi_scan_lock);
65 }
66 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
67
68 void acpi_scan_lock_release(void)
69 {
70 mutex_unlock(&acpi_scan_lock);
71 }
72 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
73
74 void acpi_lock_hp_context(void)
75 {
76 mutex_lock(&acpi_hp_context_lock);
77 }
78
79 void acpi_unlock_hp_context(void)
80 {
81 mutex_unlock(&acpi_hp_context_lock);
82 }
83
84 void acpi_initialize_hp_context(struct acpi_device *adev,
85 struct acpi_hotplug_context *hp,
86 int (*notify)(struct acpi_device *, u32),
87 void (*uevent)(struct acpi_device *, u32))
88 {
89 acpi_lock_hp_context();
90 hp->notify = notify;
91 hp->uevent = uevent;
92 acpi_set_hp_context(adev, hp);
93 acpi_unlock_hp_context();
94 }
95 EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
96
97 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
98 {
99 if (!handler)
100 return -EINVAL;
101
102 list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
103 return 0;
104 }
105
106 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
107 const char *hotplug_profile_name)
108 {
109 int error;
110
111 error = acpi_scan_add_handler(handler);
112 if (error)
113 return error;
114
115 acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
116 return 0;
117 }
118
119 bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
120 {
121 struct acpi_device_physical_node *pn;
122 bool offline = true;
123
124 /*
125 * acpi_container_offline() calls this for all of the container's
126 * children under the container's physical_node_lock lock.
127 */
128 mutex_lock_nested(&adev->physical_node_lock, SINGLE_DEPTH_NESTING);
129
130 list_for_each_entry(pn, &adev->physical_node_list, node)
131 if (device_supports_offline(pn->dev) && !pn->dev->offline) {
132 if (uevent)
133 kobject_uevent(&pn->dev->kobj, KOBJ_CHANGE);
134
135 offline = false;
136 break;
137 }
138
139 mutex_unlock(&adev->physical_node_lock);
140 return offline;
141 }
142
143 static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
144 void **ret_p)
145 {
146 struct acpi_device *device = NULL;
147 struct acpi_device_physical_node *pn;
148 bool second_pass = (bool)data;
149 acpi_status status = AE_OK;
150
151 if (acpi_bus_get_device(handle, &device))
152 return AE_OK;
153
154 if (device->handler && !device->handler->hotplug.enabled) {
155 *ret_p = &device->dev;
156 return AE_SUPPORT;
157 }
158
159 mutex_lock(&device->physical_node_lock);
160
161 list_for_each_entry(pn, &device->physical_node_list, node) {
162 int ret;
163
164 if (second_pass) {
165 /* Skip devices offlined by the first pass. */
166 if (pn->put_online)
167 continue;
168 } else {
169 pn->put_online = false;
170 }
171 ret = device_offline(pn->dev);
172 if (acpi_force_hot_remove)
173 continue;
174
175 if (ret >= 0) {
176 pn->put_online = !ret;
177 } else {
178 *ret_p = pn->dev;
179 if (second_pass) {
180 status = AE_ERROR;
181 break;
182 }
183 }
184 }
185
186 mutex_unlock(&device->physical_node_lock);
187
188 return status;
189 }
190
191 static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
192 void **ret_p)
193 {
194 struct acpi_device *device = NULL;
195 struct acpi_device_physical_node *pn;
196
197 if (acpi_bus_get_device(handle, &device))
198 return AE_OK;
199
200 mutex_lock(&device->physical_node_lock);
201
202 list_for_each_entry(pn, &device->physical_node_list, node)
203 if (pn->put_online) {
204 device_online(pn->dev);
205 pn->put_online = false;
206 }
207
208 mutex_unlock(&device->physical_node_lock);
209
210 return AE_OK;
211 }
212
213 static int acpi_scan_try_to_offline(struct acpi_device *device)
214 {
215 acpi_handle handle = device->handle;
216 struct device *errdev = NULL;
217 acpi_status status;
218
219 /*
220 * Carry out two passes here and ignore errors in the first pass,
221 * because if the devices in question are memory blocks and
222 * CONFIG_MEMCG is set, one of the blocks may hold data structures
223 * that the other blocks depend on, but it is not known in advance which
224 * block holds them.
225 *
226 * If the first pass is successful, the second one isn't needed, though.
227 */
228 status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
229 NULL, acpi_bus_offline, (void *)false,
230 (void **)&errdev);
231 if (status == AE_SUPPORT) {
232 dev_warn(errdev, "Offline disabled.\n");
233 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
234 acpi_bus_online, NULL, NULL, NULL);
235 return -EPERM;
236 }
237 acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
238 if (errdev) {
239 errdev = NULL;
240 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
241 NULL, acpi_bus_offline, (void *)true,
242 (void **)&errdev);
243 if (!errdev || acpi_force_hot_remove)
244 acpi_bus_offline(handle, 0, (void *)true,
245 (void **)&errdev);
246
247 if (errdev && !acpi_force_hot_remove) {
248 dev_warn(errdev, "Offline failed.\n");
249 acpi_bus_online(handle, 0, NULL, NULL);
250 acpi_walk_namespace(ACPI_TYPE_ANY, handle,
251 ACPI_UINT32_MAX, acpi_bus_online,
252 NULL, NULL, NULL);
253 return -EBUSY;
254 }
255 }
256 return 0;
257 }
258
259 static int acpi_scan_hot_remove(struct acpi_device *device)
260 {
261 acpi_handle handle = device->handle;
262 unsigned long long sta;
263 acpi_status status;
264
265 if (device->handler && device->handler->hotplug.demand_offline
266 && !acpi_force_hot_remove) {
267 if (!acpi_scan_is_offline(device, true))
268 return -EBUSY;
269 } else {
270 int error = acpi_scan_try_to_offline(device);
271 if (error)
272 return error;
273 }
274
275 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
276 "Hot-removing device %s...\n", dev_name(&device->dev)));
277
278 acpi_bus_trim(device);
279
280 acpi_evaluate_lck(handle, 0);
281 /*
282 * TBD: _EJD support.
283 */
284 status = acpi_evaluate_ej0(handle);
285 if (status == AE_NOT_FOUND)
286 return -ENODEV;
287 else if (ACPI_FAILURE(status))
288 return -EIO;
289
290 /*
291 * Verify if eject was indeed successful. If not, log an error
292 * message. No need to call _OST since _EJ0 call was made OK.
293 */
294 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
295 if (ACPI_FAILURE(status)) {
296 acpi_handle_warn(handle,
297 "Status check after eject failed (0x%x)\n", status);
298 } else if (sta & ACPI_STA_DEVICE_ENABLED) {
299 acpi_handle_warn(handle,
300 "Eject incomplete - status 0x%llx\n", sta);
301 }
302
303 return 0;
304 }
305
306 static int acpi_scan_device_not_present(struct acpi_device *adev)
307 {
308 if (!acpi_device_enumerated(adev)) {
309 dev_warn(&adev->dev, "Still not present\n");
310 return -EALREADY;
311 }
312 acpi_bus_trim(adev);
313 return 0;
314 }
315
316 static int acpi_scan_device_check(struct acpi_device *adev)
317 {
318 int error;
319
320 acpi_bus_get_status(adev);
321 if (adev->status.present || adev->status.functional) {
322 /*
323 * This function is only called for device objects for which
324 * matching scan handlers exist. The only situation in which
325 * the scan handler is not attached to this device object yet
326 * is when the device has just appeared (either it wasn't
327 * present at all before or it was removed and then added
328 * again).
329 */
330 if (adev->handler) {
331 dev_warn(&adev->dev, "Already enumerated\n");
332 return -EALREADY;
333 }
334 error = acpi_bus_scan(adev->handle);
335 if (error) {
336 dev_warn(&adev->dev, "Namespace scan failure\n");
337 return error;
338 }
339 if (!adev->handler) {
340 dev_warn(&adev->dev, "Enumeration failure\n");
341 error = -ENODEV;
342 }
343 } else {
344 error = acpi_scan_device_not_present(adev);
345 }
346 return error;
347 }
348
349 static int acpi_scan_bus_check(struct acpi_device *adev)
350 {
351 struct acpi_scan_handler *handler = adev->handler;
352 struct acpi_device *child;
353 int error;
354
355 acpi_bus_get_status(adev);
356 if (!(adev->status.present || adev->status.functional)) {
357 acpi_scan_device_not_present(adev);
358 return 0;
359 }
360 if (handler && handler->hotplug.scan_dependent)
361 return handler->hotplug.scan_dependent(adev);
362
363 error = acpi_bus_scan(adev->handle);
364 if (error) {
365 dev_warn(&adev->dev, "Namespace scan failure\n");
366 return error;
367 }
368 list_for_each_entry(child, &adev->children, node) {
369 error = acpi_scan_bus_check(child);
370 if (error)
371 return error;
372 }
373 return 0;
374 }
375
376 static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type)
377 {
378 switch (type) {
379 case ACPI_NOTIFY_BUS_CHECK:
380 return acpi_scan_bus_check(adev);
381 case ACPI_NOTIFY_DEVICE_CHECK:
382 return acpi_scan_device_check(adev);
383 case ACPI_NOTIFY_EJECT_REQUEST:
384 case ACPI_OST_EC_OSPM_EJECT:
385 if (adev->handler && !adev->handler->hotplug.enabled) {
386 dev_info(&adev->dev, "Eject disabled\n");
387 return -EPERM;
388 }
389 acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST,
390 ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
391 return acpi_scan_hot_remove(adev);
392 }
393 return -EINVAL;
394 }
395
396 void acpi_device_hotplug(struct acpi_device *adev, u32 src)
397 {
398 u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
399 int error = -ENODEV;
400
401 lock_device_hotplug();
402 mutex_lock(&acpi_scan_lock);
403
404 /*
405 * The device object's ACPI handle cannot become invalid as long as we
406 * are holding acpi_scan_lock, but it might have become invalid before
407 * that lock was acquired.
408 */
409 if (adev->handle == INVALID_ACPI_HANDLE)
410 goto err_out;
411
412 if (adev->flags.is_dock_station) {
413 error = dock_notify(adev, src);
414 } else if (adev->flags.hotplug_notify) {
415 error = acpi_generic_hotplug_event(adev, src);
416 if (error == -EPERM) {
417 ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
418 goto err_out;
419 }
420 } else {
421 int (*notify)(struct acpi_device *, u32);
422
423 acpi_lock_hp_context();
424 notify = adev->hp ? adev->hp->notify : NULL;
425 acpi_unlock_hp_context();
426 /*
427 * There may be additional notify handlers for device objects
428 * without the .event() callback, so ignore them here.
429 */
430 if (notify)
431 error = notify(adev, src);
432 else
433 goto out;
434 }
435 if (!error)
436 ost_code = ACPI_OST_SC_SUCCESS;
437
438 err_out:
439 acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
440
441 out:
442 acpi_bus_put_acpi_device(adev);
443 mutex_unlock(&acpi_scan_lock);
444 unlock_device_hotplug();
445 }
446
447 static void acpi_free_power_resources_lists(struct acpi_device *device)
448 {
449 int i;
450
451 if (device->wakeup.flags.valid)
452 acpi_power_resources_list_free(&device->wakeup.resources);
453
454 if (!device->power.flags.power_resources)
455 return;
456
457 for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
458 struct acpi_device_power_state *ps = &device->power.states[i];
459 acpi_power_resources_list_free(&ps->resources);
460 }
461 }
462
463 static void acpi_device_release(struct device *dev)
464 {
465 struct acpi_device *acpi_dev = to_acpi_device(dev);
466
467 acpi_free_properties(acpi_dev);
468 acpi_free_pnp_ids(&acpi_dev->pnp);
469 acpi_free_power_resources_lists(acpi_dev);
470 kfree(acpi_dev);
471 }
472
473 static void acpi_device_del(struct acpi_device *device)
474 {
475 struct acpi_device_bus_id *acpi_device_bus_id;
476
477 mutex_lock(&acpi_device_lock);
478 if (device->parent)
479 list_del(&device->node);
480
481 list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node)
482 if (!strcmp(acpi_device_bus_id->bus_id,
483 acpi_device_hid(device))) {
484 if (acpi_device_bus_id->instance_no > 0)
485 acpi_device_bus_id->instance_no--;
486 else {
487 list_del(&acpi_device_bus_id->node);
488 kfree(acpi_device_bus_id);
489 }
490 break;
491 }
492
493 list_del(&device->wakeup_list);
494 mutex_unlock(&acpi_device_lock);
495
496 acpi_power_add_remove_device(device, false);
497 acpi_device_remove_files(device);
498 if (device->remove)
499 device->remove(device);
500
501 device_del(&device->dev);
502 }
503
504 static BLOCKING_NOTIFIER_HEAD(acpi_reconfig_chain);
505
506 static LIST_HEAD(acpi_device_del_list);
507 static DEFINE_MUTEX(acpi_device_del_lock);
508
509 static void acpi_device_del_work_fn(struct work_struct *work_not_used)
510 {
511 for (;;) {
512 struct acpi_device *adev;
513
514 mutex_lock(&acpi_device_del_lock);
515
516 if (list_empty(&acpi_device_del_list)) {
517 mutex_unlock(&acpi_device_del_lock);
518 break;
519 }
520 adev = list_first_entry(&acpi_device_del_list,
521 struct acpi_device, del_list);
522 list_del(&adev->del_list);
523
524 mutex_unlock(&acpi_device_del_lock);
525
526 blocking_notifier_call_chain(&acpi_reconfig_chain,
527 ACPI_RECONFIG_DEVICE_REMOVE, adev);
528
529 acpi_device_del(adev);
530 /*
531 * Drop references to all power resources that might have been
532 * used by the device.
533 */
534 acpi_power_transition(adev, ACPI_STATE_D3_COLD);
535 put_device(&adev->dev);
536 }
537 }
538
539 /**
540 * acpi_scan_drop_device - Drop an ACPI device object.
541 * @handle: Handle of an ACPI namespace node, not used.
542 * @context: Address of the ACPI device object to drop.
543 *
544 * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
545 * namespace node the device object pointed to by @context is attached to.
546 *
547 * The unregistration is carried out asynchronously to avoid running
548 * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
549 * ensure the correct ordering (the device objects must be unregistered in the
550 * same order in which the corresponding namespace nodes are deleted).
551 */
552 static void acpi_scan_drop_device(acpi_handle handle, void *context)
553 {
554 static DECLARE_WORK(work, acpi_device_del_work_fn);
555 struct acpi_device *adev = context;
556
557 mutex_lock(&acpi_device_del_lock);
558
559 /*
560 * Use the ACPI hotplug workqueue which is ordered, so this work item
561 * won't run after any hotplug work items submitted subsequently. That
562 * prevents attempts to register device objects identical to those being
563 * deleted from happening concurrently (such attempts result from
564 * hotplug events handled via the ACPI hotplug workqueue). It also will
565 * run after all of the work items submitted previosuly, which helps
566 * those work items to ensure that they are not accessing stale device
567 * objects.
568 */
569 if (list_empty(&acpi_device_del_list))
570 acpi_queue_hotplug_work(&work);
571
572 list_add_tail(&adev->del_list, &acpi_device_del_list);
573 /* Make acpi_ns_validate_handle() return NULL for this handle. */
574 adev->handle = INVALID_ACPI_HANDLE;
575
576 mutex_unlock(&acpi_device_del_lock);
577 }
578
579 static int acpi_get_device_data(acpi_handle handle, struct acpi_device **device,
580 void (*callback)(void *))
581 {
582 acpi_status status;
583
584 if (!device)
585 return -EINVAL;
586
587 status = acpi_get_data_full(handle, acpi_scan_drop_device,
588 (void **)device, callback);
589 if (ACPI_FAILURE(status) || !*device) {
590 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
591 handle));
592 return -ENODEV;
593 }
594 return 0;
595 }
596
597 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
598 {
599 return acpi_get_device_data(handle, device, NULL);
600 }
601 EXPORT_SYMBOL(acpi_bus_get_device);
602
603 static void get_acpi_device(void *dev)
604 {
605 if (dev)
606 get_device(&((struct acpi_device *)dev)->dev);
607 }
608
609 struct acpi_device *acpi_bus_get_acpi_device(acpi_handle handle)
610 {
611 struct acpi_device *adev = NULL;
612
613 acpi_get_device_data(handle, &adev, get_acpi_device);
614 return adev;
615 }
616
617 void acpi_bus_put_acpi_device(struct acpi_device *adev)
618 {
619 put_device(&adev->dev);
620 }
621
622 int acpi_device_add(struct acpi_device *device,
623 void (*release)(struct device *))
624 {
625 int result;
626 struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
627 int found = 0;
628
629 if (device->handle) {
630 acpi_status status;
631
632 status = acpi_attach_data(device->handle, acpi_scan_drop_device,
633 device);
634 if (ACPI_FAILURE(status)) {
635 acpi_handle_err(device->handle,
636 "Unable to attach device data\n");
637 return -ENODEV;
638 }
639 }
640
641 /*
642 * Linkage
643 * -------
644 * Link this device to its parent and siblings.
645 */
646 INIT_LIST_HEAD(&device->children);
647 INIT_LIST_HEAD(&device->node);
648 INIT_LIST_HEAD(&device->wakeup_list);
649 INIT_LIST_HEAD(&device->physical_node_list);
650 INIT_LIST_HEAD(&device->del_list);
651 mutex_init(&device->physical_node_lock);
652
653 new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
654 if (!new_bus_id) {
655 pr_err(PREFIX "Memory allocation error\n");
656 result = -ENOMEM;
657 goto err_detach;
658 }
659
660 mutex_lock(&acpi_device_lock);
661 /*
662 * Find suitable bus_id and instance number in acpi_bus_id_list
663 * If failed, create one and link it into acpi_bus_id_list
664 */
665 list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
666 if (!strcmp(acpi_device_bus_id->bus_id,
667 acpi_device_hid(device))) {
668 acpi_device_bus_id->instance_no++;
669 found = 1;
670 kfree(new_bus_id);
671 break;
672 }
673 }
674 if (!found) {
675 acpi_device_bus_id = new_bus_id;
676 strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
677 acpi_device_bus_id->instance_no = 0;
678 list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
679 }
680 dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
681
682 if (device->parent)
683 list_add_tail(&device->node, &device->parent->children);
684
685 if (device->wakeup.flags.valid)
686 list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
687 mutex_unlock(&acpi_device_lock);
688
689 if (device->parent)
690 device->dev.parent = &device->parent->dev;
691 device->dev.bus = &acpi_bus_type;
692 device->dev.release = release;
693 result = device_add(&device->dev);
694 if (result) {
695 dev_err(&device->dev, "Error registering device\n");
696 goto err;
697 }
698
699 result = acpi_device_setup_files(device);
700 if (result)
701 printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
702 dev_name(&device->dev));
703
704 return 0;
705
706 err:
707 mutex_lock(&acpi_device_lock);
708 if (device->parent)
709 list_del(&device->node);
710 list_del(&device->wakeup_list);
711 mutex_unlock(&acpi_device_lock);
712
713 err_detach:
714 acpi_detach_data(device->handle, acpi_scan_drop_device);
715 return result;
716 }
717
718 /* --------------------------------------------------------------------------
719 Device Enumeration
720 -------------------------------------------------------------------------- */
721 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
722 {
723 struct acpi_device *device = NULL;
724 acpi_status status;
725
726 /*
727 * Fixed hardware devices do not appear in the namespace and do not
728 * have handles, but we fabricate acpi_devices for them, so we have
729 * to deal with them specially.
730 */
731 if (!handle)
732 return acpi_root;
733
734 do {
735 status = acpi_get_parent(handle, &handle);
736 if (ACPI_FAILURE(status))
737 return status == AE_NULL_ENTRY ? NULL : acpi_root;
738 } while (acpi_bus_get_device(handle, &device));
739 return device;
740 }
741
742 acpi_status
743 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
744 {
745 acpi_status status;
746 acpi_handle tmp;
747 struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
748 union acpi_object *obj;
749
750 status = acpi_get_handle(handle, "_EJD", &tmp);
751 if (ACPI_FAILURE(status))
752 return status;
753
754 status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
755 if (ACPI_SUCCESS(status)) {
756 obj = buffer.pointer;
757 status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
758 ejd);
759 kfree(buffer.pointer);
760 }
761 return status;
762 }
763 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
764
765 static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
766 struct acpi_device_wakeup *wakeup)
767 {
768 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
769 union acpi_object *package = NULL;
770 union acpi_object *element = NULL;
771 acpi_status status;
772 int err = -ENODATA;
773
774 if (!wakeup)
775 return -EINVAL;
776
777 INIT_LIST_HEAD(&wakeup->resources);
778
779 /* _PRW */
780 status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
781 if (ACPI_FAILURE(status)) {
782 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
783 return err;
784 }
785
786 package = (union acpi_object *)buffer.pointer;
787
788 if (!package || package->package.count < 2)
789 goto out;
790
791 element = &(package->package.elements[0]);
792 if (!element)
793 goto out;
794
795 if (element->type == ACPI_TYPE_PACKAGE) {
796 if ((element->package.count < 2) ||
797 (element->package.elements[0].type !=
798 ACPI_TYPE_LOCAL_REFERENCE)
799 || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
800 goto out;
801
802 wakeup->gpe_device =
803 element->package.elements[0].reference.handle;
804 wakeup->gpe_number =
805 (u32) element->package.elements[1].integer.value;
806 } else if (element->type == ACPI_TYPE_INTEGER) {
807 wakeup->gpe_device = NULL;
808 wakeup->gpe_number = element->integer.value;
809 } else {
810 goto out;
811 }
812
813 element = &(package->package.elements[1]);
814 if (element->type != ACPI_TYPE_INTEGER)
815 goto out;
816
817 wakeup->sleep_state = element->integer.value;
818
819 err = acpi_extract_power_resources(package, 2, &wakeup->resources);
820 if (err)
821 goto out;
822
823 if (!list_empty(&wakeup->resources)) {
824 int sleep_state;
825
826 err = acpi_power_wakeup_list_init(&wakeup->resources,
827 &sleep_state);
828 if (err) {
829 acpi_handle_warn(handle, "Retrieving current states "
830 "of wakeup power resources failed\n");
831 acpi_power_resources_list_free(&wakeup->resources);
832 goto out;
833 }
834 if (sleep_state < wakeup->sleep_state) {
835 acpi_handle_warn(handle, "Overriding _PRW sleep state "
836 "(S%d) by S%d from power resources\n",
837 (int)wakeup->sleep_state, sleep_state);
838 wakeup->sleep_state = sleep_state;
839 }
840 }
841
842 out:
843 kfree(buffer.pointer);
844 return err;
845 }
846
847 static void acpi_wakeup_gpe_init(struct acpi_device *device)
848 {
849 static const struct acpi_device_id button_device_ids[] = {
850 {"PNP0C0C", 0},
851 {"PNP0C0D", 0},
852 {"PNP0C0E", 0},
853 {"", 0},
854 };
855 struct acpi_device_wakeup *wakeup = &device->wakeup;
856 acpi_status status;
857 acpi_event_status event_status;
858
859 wakeup->flags.notifier_present = 0;
860
861 /* Power button, Lid switch always enable wakeup */
862 if (!acpi_match_device_ids(device, button_device_ids)) {
863 wakeup->flags.run_wake = 1;
864 if (!acpi_match_device_ids(device, &button_device_ids[1])) {
865 /* Do not use Lid/sleep button for S5 wakeup */
866 if (wakeup->sleep_state == ACPI_STATE_S5)
867 wakeup->sleep_state = ACPI_STATE_S4;
868 }
869 acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
870 device_set_wakeup_capable(&device->dev, true);
871 return;
872 }
873
874 acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
875 wakeup->gpe_number);
876 status = acpi_get_gpe_status(wakeup->gpe_device, wakeup->gpe_number,
877 &event_status);
878 if (ACPI_FAILURE(status))
879 return;
880
881 wakeup->flags.run_wake = !!(event_status & ACPI_EVENT_FLAG_HAS_HANDLER);
882 }
883
884 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
885 {
886 int err;
887
888 /* Presence of _PRW indicates wake capable */
889 if (!acpi_has_method(device->handle, "_PRW"))
890 return;
891
892 err = acpi_bus_extract_wakeup_device_power_package(device->handle,
893 &device->wakeup);
894 if (err) {
895 dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
896 return;
897 }
898
899 device->wakeup.flags.valid = 1;
900 device->wakeup.prepare_count = 0;
901 acpi_wakeup_gpe_init(device);
902 /* Call _PSW/_DSW object to disable its ability to wake the sleeping
903 * system for the ACPI device with the _PRW object.
904 * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
905 * So it is necessary to call _DSW object first. Only when it is not
906 * present will the _PSW object used.
907 */
908 err = acpi_device_sleep_wake(device, 0, 0, 0);
909 if (err)
910 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
911 "error in _DSW or _PSW evaluation\n"));
912 }
913
914 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
915 {
916 struct acpi_device_power_state *ps = &device->power.states[state];
917 char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
918 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
919 acpi_status status;
920
921 INIT_LIST_HEAD(&ps->resources);
922
923 /* Evaluate "_PRx" to get referenced power resources */
924 status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
925 if (ACPI_SUCCESS(status)) {
926 union acpi_object *package = buffer.pointer;
927
928 if (buffer.length && package
929 && package->type == ACPI_TYPE_PACKAGE
930 && package->package.count) {
931 int err = acpi_extract_power_resources(package, 0,
932 &ps->resources);
933 if (!err)
934 device->power.flags.power_resources = 1;
935 }
936 ACPI_FREE(buffer.pointer);
937 }
938
939 /* Evaluate "_PSx" to see if we can do explicit sets */
940 pathname[2] = 'S';
941 if (acpi_has_method(device->handle, pathname))
942 ps->flags.explicit_set = 1;
943
944 /* State is valid if there are means to put the device into it. */
945 if (!list_empty(&ps->resources) || ps->flags.explicit_set)
946 ps->flags.valid = 1;
947
948 ps->power = -1; /* Unknown - driver assigned */
949 ps->latency = -1; /* Unknown - driver assigned */
950 }
951
952 static void acpi_bus_get_power_flags(struct acpi_device *device)
953 {
954 u32 i;
955
956 /* Presence of _PS0|_PR0 indicates 'power manageable' */
957 if (!acpi_has_method(device->handle, "_PS0") &&
958 !acpi_has_method(device->handle, "_PR0"))
959 return;
960
961 device->flags.power_manageable = 1;
962
963 /*
964 * Power Management Flags
965 */
966 if (acpi_has_method(device->handle, "_PSC"))
967 device->power.flags.explicit_get = 1;
968
969 if (acpi_has_method(device->handle, "_IRC"))
970 device->power.flags.inrush_current = 1;
971
972 if (acpi_has_method(device->handle, "_DSW"))
973 device->power.flags.dsw_present = 1;
974
975 /*
976 * Enumerate supported power management states
977 */
978 for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
979 acpi_bus_init_power_state(device, i);
980
981 INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
982 if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources))
983 device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
984
985 /* Set defaults for D0 and D3hot states (always valid) */
986 device->power.states[ACPI_STATE_D0].flags.valid = 1;
987 device->power.states[ACPI_STATE_D0].power = 100;
988 device->power.states[ACPI_STATE_D3_HOT].flags.valid = 1;
989
990 if (acpi_bus_init_power(device))
991 device->flags.power_manageable = 0;
992 }
993
994 static void acpi_bus_get_flags(struct acpi_device *device)
995 {
996 /* Presence of _STA indicates 'dynamic_status' */
997 if (acpi_has_method(device->handle, "_STA"))
998 device->flags.dynamic_status = 1;
999
1000 /* Presence of _RMV indicates 'removable' */
1001 if (acpi_has_method(device->handle, "_RMV"))
1002 device->flags.removable = 1;
1003
1004 /* Presence of _EJD|_EJ0 indicates 'ejectable' */
1005 if (acpi_has_method(device->handle, "_EJD") ||
1006 acpi_has_method(device->handle, "_EJ0"))
1007 device->flags.ejectable = 1;
1008 }
1009
1010 static void acpi_device_get_busid(struct acpi_device *device)
1011 {
1012 char bus_id[5] = { '?', 0 };
1013 struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1014 int i = 0;
1015
1016 /*
1017 * Bus ID
1018 * ------
1019 * The device's Bus ID is simply the object name.
1020 * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1021 */
1022 if (ACPI_IS_ROOT_DEVICE(device)) {
1023 strcpy(device->pnp.bus_id, "ACPI");
1024 return;
1025 }
1026
1027 switch (device->device_type) {
1028 case ACPI_BUS_TYPE_POWER_BUTTON:
1029 strcpy(device->pnp.bus_id, "PWRF");
1030 break;
1031 case ACPI_BUS_TYPE_SLEEP_BUTTON:
1032 strcpy(device->pnp.bus_id, "SLPF");
1033 break;
1034 default:
1035 acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1036 /* Clean up trailing underscores (if any) */
1037 for (i = 3; i > 1; i--) {
1038 if (bus_id[i] == '_')
1039 bus_id[i] = '\0';
1040 else
1041 break;
1042 }
1043 strcpy(device->pnp.bus_id, bus_id);
1044 break;
1045 }
1046 }
1047
1048 /*
1049 * acpi_ata_match - see if an acpi object is an ATA device
1050 *
1051 * If an acpi object has one of the ACPI ATA methods defined,
1052 * then we can safely call it an ATA device.
1053 */
1054 bool acpi_ata_match(acpi_handle handle)
1055 {
1056 return acpi_has_method(handle, "_GTF") ||
1057 acpi_has_method(handle, "_GTM") ||
1058 acpi_has_method(handle, "_STM") ||
1059 acpi_has_method(handle, "_SDD");
1060 }
1061
1062 /*
1063 * acpi_bay_match - see if an acpi object is an ejectable driver bay
1064 *
1065 * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1066 * then we can safely call it an ejectable drive bay
1067 */
1068 bool acpi_bay_match(acpi_handle handle)
1069 {
1070 acpi_handle phandle;
1071
1072 if (!acpi_has_method(handle, "_EJ0"))
1073 return false;
1074 if (acpi_ata_match(handle))
1075 return true;
1076 if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1077 return false;
1078
1079 return acpi_ata_match(phandle);
1080 }
1081
1082 bool acpi_device_is_battery(struct acpi_device *adev)
1083 {
1084 struct acpi_hardware_id *hwid;
1085
1086 list_for_each_entry(hwid, &adev->pnp.ids, list)
1087 if (!strcmp("PNP0C0A", hwid->id))
1088 return true;
1089
1090 return false;
1091 }
1092
1093 static bool is_ejectable_bay(struct acpi_device *adev)
1094 {
1095 acpi_handle handle = adev->handle;
1096
1097 if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
1098 return true;
1099
1100 return acpi_bay_match(handle);
1101 }
1102
1103 /*
1104 * acpi_dock_match - see if an acpi object has a _DCK method
1105 */
1106 bool acpi_dock_match(acpi_handle handle)
1107 {
1108 return acpi_has_method(handle, "_DCK");
1109 }
1110
1111 static acpi_status
1112 acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
1113 void **return_value)
1114 {
1115 long *cap = context;
1116
1117 if (acpi_has_method(handle, "_BCM") &&
1118 acpi_has_method(handle, "_BCL")) {
1119 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight "
1120 "support\n"));
1121 *cap |= ACPI_VIDEO_BACKLIGHT;
1122 if (!acpi_has_method(handle, "_BQC"))
1123 printk(KERN_WARNING FW_BUG PREFIX "No _BQC method, "
1124 "cannot determine initial brightness\n");
1125 /* We have backlight support, no need to scan further */
1126 return AE_CTRL_TERMINATE;
1127 }
1128 return 0;
1129 }
1130
1131 /* Returns true if the ACPI object is a video device which can be
1132 * handled by video.ko.
1133 * The device will get a Linux specific CID added in scan.c to
1134 * identify the device as an ACPI graphics device
1135 * Be aware that the graphics device may not be physically present
1136 * Use acpi_video_get_capabilities() to detect general ACPI video
1137 * capabilities of present cards
1138 */
1139 long acpi_is_video_device(acpi_handle handle)
1140 {
1141 long video_caps = 0;
1142
1143 /* Is this device able to support video switching ? */
1144 if (acpi_has_method(handle, "_DOD") || acpi_has_method(handle, "_DOS"))
1145 video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
1146
1147 /* Is this device able to retrieve a video ROM ? */
1148 if (acpi_has_method(handle, "_ROM"))
1149 video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
1150
1151 /* Is this device able to configure which video head to be POSTed ? */
1152 if (acpi_has_method(handle, "_VPO") &&
1153 acpi_has_method(handle, "_GPD") &&
1154 acpi_has_method(handle, "_SPD"))
1155 video_caps |= ACPI_VIDEO_DEVICE_POSTING;
1156
1157 /* Only check for backlight functionality if one of the above hit. */
1158 if (video_caps)
1159 acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
1160 ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
1161 &video_caps, NULL);
1162
1163 return video_caps;
1164 }
1165 EXPORT_SYMBOL(acpi_is_video_device);
1166
1167 const char *acpi_device_hid(struct acpi_device *device)
1168 {
1169 struct acpi_hardware_id *hid;
1170
1171 if (list_empty(&device->pnp.ids))
1172 return dummy_hid;
1173
1174 hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1175 return hid->id;
1176 }
1177 EXPORT_SYMBOL(acpi_device_hid);
1178
1179 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1180 {
1181 struct acpi_hardware_id *id;
1182
1183 id = kmalloc(sizeof(*id), GFP_KERNEL);
1184 if (!id)
1185 return;
1186
1187 id->id = kstrdup_const(dev_id, GFP_KERNEL);
1188 if (!id->id) {
1189 kfree(id);
1190 return;
1191 }
1192
1193 list_add_tail(&id->list, &pnp->ids);
1194 pnp->type.hardware_id = 1;
1195 }
1196
1197 /*
1198 * Old IBM workstations have a DSDT bug wherein the SMBus object
1199 * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1200 * prefix. Work around this.
1201 */
1202 static bool acpi_ibm_smbus_match(acpi_handle handle)
1203 {
1204 char node_name[ACPI_PATH_SEGMENT_LENGTH];
1205 struct acpi_buffer path = { sizeof(node_name), node_name };
1206
1207 if (!dmi_name_in_vendors("IBM"))
1208 return false;
1209
1210 /* Look for SMBS object */
1211 if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1212 strcmp("SMBS", path.pointer))
1213 return false;
1214
1215 /* Does it have the necessary (but misnamed) methods? */
1216 if (acpi_has_method(handle, "SBI") &&
1217 acpi_has_method(handle, "SBR") &&
1218 acpi_has_method(handle, "SBW"))
1219 return true;
1220
1221 return false;
1222 }
1223
1224 static bool acpi_object_is_system_bus(acpi_handle handle)
1225 {
1226 acpi_handle tmp;
1227
1228 if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
1229 tmp == handle)
1230 return true;
1231 if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
1232 tmp == handle)
1233 return true;
1234
1235 return false;
1236 }
1237
1238 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1239 int device_type)
1240 {
1241 acpi_status status;
1242 struct acpi_device_info *info;
1243 struct acpi_pnp_device_id_list *cid_list;
1244 int i;
1245
1246 switch (device_type) {
1247 case ACPI_BUS_TYPE_DEVICE:
1248 if (handle == ACPI_ROOT_OBJECT) {
1249 acpi_add_id(pnp, ACPI_SYSTEM_HID);
1250 break;
1251 }
1252
1253 status = acpi_get_object_info(handle, &info);
1254 if (ACPI_FAILURE(status)) {
1255 pr_err(PREFIX "%s: Error reading device info\n",
1256 __func__);
1257 return;
1258 }
1259
1260 if (info->valid & ACPI_VALID_HID) {
1261 acpi_add_id(pnp, info->hardware_id.string);
1262 pnp->type.platform_id = 1;
1263 }
1264 if (info->valid & ACPI_VALID_CID) {
1265 cid_list = &info->compatible_id_list;
1266 for (i = 0; i < cid_list->count; i++)
1267 acpi_add_id(pnp, cid_list->ids[i].string);
1268 }
1269 if (info->valid & ACPI_VALID_ADR) {
1270 pnp->bus_address = info->address;
1271 pnp->type.bus_address = 1;
1272 }
1273 if (info->valid & ACPI_VALID_UID)
1274 pnp->unique_id = kstrdup(info->unique_id.string,
1275 GFP_KERNEL);
1276 if (info->valid & ACPI_VALID_CLS)
1277 acpi_add_id(pnp, info->class_code.string);
1278
1279 kfree(info);
1280
1281 /*
1282 * Some devices don't reliably have _HIDs & _CIDs, so add
1283 * synthetic HIDs to make sure drivers can find them.
1284 */
1285 if (acpi_is_video_device(handle))
1286 acpi_add_id(pnp, ACPI_VIDEO_HID);
1287 else if (acpi_bay_match(handle))
1288 acpi_add_id(pnp, ACPI_BAY_HID);
1289 else if (acpi_dock_match(handle))
1290 acpi_add_id(pnp, ACPI_DOCK_HID);
1291 else if (acpi_ibm_smbus_match(handle))
1292 acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1293 else if (list_empty(&pnp->ids) &&
1294 acpi_object_is_system_bus(handle)) {
1295 /* \_SB, \_TZ, LNXSYBUS */
1296 acpi_add_id(pnp, ACPI_BUS_HID);
1297 strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1298 strcpy(pnp->device_class, ACPI_BUS_CLASS);
1299 }
1300
1301 break;
1302 case ACPI_BUS_TYPE_POWER:
1303 acpi_add_id(pnp, ACPI_POWER_HID);
1304 break;
1305 case ACPI_BUS_TYPE_PROCESSOR:
1306 acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1307 break;
1308 case ACPI_BUS_TYPE_THERMAL:
1309 acpi_add_id(pnp, ACPI_THERMAL_HID);
1310 break;
1311 case ACPI_BUS_TYPE_POWER_BUTTON:
1312 acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1313 break;
1314 case ACPI_BUS_TYPE_SLEEP_BUTTON:
1315 acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1316 break;
1317 }
1318 }
1319
1320 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1321 {
1322 struct acpi_hardware_id *id, *tmp;
1323
1324 list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1325 kfree_const(id->id);
1326 kfree(id);
1327 }
1328 kfree(pnp->unique_id);
1329 }
1330
1331 /**
1332 * acpi_dma_supported - Check DMA support for the specified device.
1333 * @adev: The pointer to acpi device
1334 *
1335 * Return false if DMA is not supported. Otherwise, return true
1336 */
1337 bool acpi_dma_supported(struct acpi_device *adev)
1338 {
1339 if (!adev)
1340 return false;
1341
1342 if (adev->flags.cca_seen)
1343 return true;
1344
1345 /*
1346 * Per ACPI 6.0 sec 6.2.17, assume devices can do cache-coherent
1347 * DMA on "Intel platforms". Presumably that includes all x86 and
1348 * ia64, and other arches will set CONFIG_ACPI_CCA_REQUIRED=y.
1349 */
1350 if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1351 return true;
1352
1353 return false;
1354 }
1355
1356 /**
1357 * acpi_get_dma_attr - Check the supported DMA attr for the specified device.
1358 * @adev: The pointer to acpi device
1359 *
1360 * Return enum dev_dma_attr.
1361 */
1362 enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
1363 {
1364 if (!acpi_dma_supported(adev))
1365 return DEV_DMA_NOT_SUPPORTED;
1366
1367 if (adev->flags.coherent_dma)
1368 return DEV_DMA_COHERENT;
1369 else
1370 return DEV_DMA_NON_COHERENT;
1371 }
1372
1373 static void acpi_init_coherency(struct acpi_device *adev)
1374 {
1375 unsigned long long cca = 0;
1376 acpi_status status;
1377 struct acpi_device *parent = adev->parent;
1378
1379 if (parent && parent->flags.cca_seen) {
1380 /*
1381 * From ACPI spec, OSPM will ignore _CCA if an ancestor
1382 * already saw one.
1383 */
1384 adev->flags.cca_seen = 1;
1385 cca = parent->flags.coherent_dma;
1386 } else {
1387 status = acpi_evaluate_integer(adev->handle, "_CCA",
1388 NULL, &cca);
1389 if (ACPI_SUCCESS(status))
1390 adev->flags.cca_seen = 1;
1391 else if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1392 /*
1393 * If architecture does not specify that _CCA is
1394 * required for DMA-able devices (e.g. x86),
1395 * we default to _CCA=1.
1396 */
1397 cca = 1;
1398 else
1399 acpi_handle_debug(adev->handle,
1400 "ACPI device is missing _CCA.\n");
1401 }
1402
1403 adev->flags.coherent_dma = cca;
1404 }
1405
1406 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1407 int type, unsigned long long sta)
1408 {
1409 INIT_LIST_HEAD(&device->pnp.ids);
1410 device->device_type = type;
1411 device->handle = handle;
1412 device->parent = acpi_bus_get_parent(handle);
1413 device->fwnode.type = FWNODE_ACPI;
1414 acpi_set_device_status(device, sta);
1415 acpi_device_get_busid(device);
1416 acpi_set_pnp_ids(handle, &device->pnp, type);
1417 acpi_init_properties(device);
1418 acpi_bus_get_flags(device);
1419 device->flags.match_driver = false;
1420 device->flags.initialized = true;
1421 acpi_device_clear_enumerated(device);
1422 device_initialize(&device->dev);
1423 dev_set_uevent_suppress(&device->dev, true);
1424 acpi_init_coherency(device);
1425 }
1426
1427 void acpi_device_add_finalize(struct acpi_device *device)
1428 {
1429 dev_set_uevent_suppress(&device->dev, false);
1430 kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1431 }
1432
1433 static int acpi_add_single_object(struct acpi_device **child,
1434 acpi_handle handle, int type,
1435 unsigned long long sta)
1436 {
1437 int result;
1438 struct acpi_device *device;
1439 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1440
1441 device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1442 if (!device) {
1443 printk(KERN_ERR PREFIX "Memory allocation error\n");
1444 return -ENOMEM;
1445 }
1446
1447 acpi_init_device_object(device, handle, type, sta);
1448 acpi_bus_get_power_flags(device);
1449 acpi_bus_get_wakeup_device_flags(device);
1450
1451 result = acpi_device_add(device, acpi_device_release);
1452 if (result) {
1453 acpi_device_release(&device->dev);
1454 return result;
1455 }
1456
1457 acpi_power_add_remove_device(device, true);
1458 acpi_device_add_finalize(device);
1459 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1460 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1461 dev_name(&device->dev), (char *) buffer.pointer,
1462 device->parent ? dev_name(&device->parent->dev) : "(null)"));
1463 kfree(buffer.pointer);
1464 *child = device;
1465 return 0;
1466 }
1467
1468 static acpi_status acpi_get_resource_memory(struct acpi_resource *ares,
1469 void *context)
1470 {
1471 struct resource *res = context;
1472
1473 if (acpi_dev_resource_memory(ares, res))
1474 return AE_CTRL_TERMINATE;
1475
1476 return AE_OK;
1477 }
1478
1479 static bool acpi_device_should_be_hidden(acpi_handle handle)
1480 {
1481 acpi_status status;
1482 struct resource res;
1483
1484 /* Check if it should ignore the UART device */
1485 if (!(spcr_uart_addr && acpi_has_method(handle, METHOD_NAME__CRS)))
1486 return false;
1487
1488 /*
1489 * The UART device described in SPCR table is assumed to have only one
1490 * memory resource present. So we only look for the first one here.
1491 */
1492 status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1493 acpi_get_resource_memory, &res);
1494 if (ACPI_FAILURE(status) || res.start != spcr_uart_addr)
1495 return false;
1496
1497 acpi_handle_info(handle, "The UART device @%pa in SPCR table will be hidden\n",
1498 &res.start);
1499
1500 return true;
1501 }
1502
1503 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1504 unsigned long long *sta)
1505 {
1506 acpi_status status;
1507 acpi_object_type acpi_type;
1508
1509 status = acpi_get_type(handle, &acpi_type);
1510 if (ACPI_FAILURE(status))
1511 return -ENODEV;
1512
1513 switch (acpi_type) {
1514 case ACPI_TYPE_ANY: /* for ACPI_ROOT_OBJECT */
1515 case ACPI_TYPE_DEVICE:
1516 if (acpi_device_should_be_hidden(handle))
1517 return -ENODEV;
1518
1519 *type = ACPI_BUS_TYPE_DEVICE;
1520 status = acpi_bus_get_status_handle(handle, sta);
1521 if (ACPI_FAILURE(status))
1522 *sta = 0;
1523 break;
1524 case ACPI_TYPE_PROCESSOR:
1525 *type = ACPI_BUS_TYPE_PROCESSOR;
1526 status = acpi_bus_get_status_handle(handle, sta);
1527 if (ACPI_FAILURE(status))
1528 return -ENODEV;
1529 break;
1530 case ACPI_TYPE_THERMAL:
1531 *type = ACPI_BUS_TYPE_THERMAL;
1532 *sta = ACPI_STA_DEFAULT;
1533 break;
1534 case ACPI_TYPE_POWER:
1535 *type = ACPI_BUS_TYPE_POWER;
1536 *sta = ACPI_STA_DEFAULT;
1537 break;
1538 default:
1539 return -ENODEV;
1540 }
1541
1542 return 0;
1543 }
1544
1545 bool acpi_device_is_present(struct acpi_device *adev)
1546 {
1547 if (adev->status.present || adev->status.functional)
1548 return true;
1549
1550 adev->flags.initialized = false;
1551 return false;
1552 }
1553
1554 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1555 const char *idstr,
1556 const struct acpi_device_id **matchid)
1557 {
1558 const struct acpi_device_id *devid;
1559
1560 if (handler->match)
1561 return handler->match(idstr, matchid);
1562
1563 for (devid = handler->ids; devid->id[0]; devid++)
1564 if (!strcmp((char *)devid->id, idstr)) {
1565 if (matchid)
1566 *matchid = devid;
1567
1568 return true;
1569 }
1570
1571 return false;
1572 }
1573
1574 static struct acpi_scan_handler *acpi_scan_match_handler(const char *idstr,
1575 const struct acpi_device_id **matchid)
1576 {
1577 struct acpi_scan_handler *handler;
1578
1579 list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1580 if (acpi_scan_handler_matching(handler, idstr, matchid))
1581 return handler;
1582
1583 return NULL;
1584 }
1585
1586 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1587 {
1588 if (!!hotplug->enabled == !!val)
1589 return;
1590
1591 mutex_lock(&acpi_scan_lock);
1592
1593 hotplug->enabled = val;
1594
1595 mutex_unlock(&acpi_scan_lock);
1596 }
1597
1598 static void acpi_scan_init_hotplug(struct acpi_device *adev)
1599 {
1600 struct acpi_hardware_id *hwid;
1601
1602 if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
1603 acpi_dock_add(adev);
1604 return;
1605 }
1606 list_for_each_entry(hwid, &adev->pnp.ids, list) {
1607 struct acpi_scan_handler *handler;
1608
1609 handler = acpi_scan_match_handler(hwid->id, NULL);
1610 if (handler) {
1611 adev->flags.hotplug_notify = true;
1612 break;
1613 }
1614 }
1615 }
1616
1617 static void acpi_device_dep_initialize(struct acpi_device *adev)
1618 {
1619 struct acpi_dep_data *dep;
1620 struct acpi_handle_list dep_devices;
1621 acpi_status status;
1622 int i;
1623
1624 if (!acpi_has_method(adev->handle, "_DEP"))
1625 return;
1626
1627 status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
1628 &dep_devices);
1629 if (ACPI_FAILURE(status)) {
1630 dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
1631 return;
1632 }
1633
1634 for (i = 0; i < dep_devices.count; i++) {
1635 struct acpi_device_info *info;
1636 int skip;
1637
1638 status = acpi_get_object_info(dep_devices.handles[i], &info);
1639 if (ACPI_FAILURE(status)) {
1640 dev_dbg(&adev->dev, "Error reading _DEP device info\n");
1641 continue;
1642 }
1643
1644 /*
1645 * Skip the dependency of Windows System Power
1646 * Management Controller
1647 */
1648 skip = info->valid & ACPI_VALID_HID &&
1649 !strcmp(info->hardware_id.string, "INT3396");
1650
1651 kfree(info);
1652
1653 if (skip)
1654 continue;
1655
1656 dep = kzalloc(sizeof(struct acpi_dep_data), GFP_KERNEL);
1657 if (!dep)
1658 return;
1659
1660 dep->master = dep_devices.handles[i];
1661 dep->slave = adev->handle;
1662 adev->dep_unmet++;
1663
1664 mutex_lock(&acpi_dep_list_lock);
1665 list_add_tail(&dep->node , &acpi_dep_list);
1666 mutex_unlock(&acpi_dep_list_lock);
1667 }
1668 }
1669
1670 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
1671 void *not_used, void **return_value)
1672 {
1673 struct acpi_device *device = NULL;
1674 int type;
1675 unsigned long long sta;
1676 int result;
1677
1678 acpi_bus_get_device(handle, &device);
1679 if (device)
1680 goto out;
1681
1682 result = acpi_bus_type_and_status(handle, &type, &sta);
1683 if (result)
1684 return AE_OK;
1685
1686 if (type == ACPI_BUS_TYPE_POWER) {
1687 acpi_add_power_resource(handle);
1688 return AE_OK;
1689 }
1690
1691 acpi_add_single_object(&device, handle, type, sta);
1692 if (!device)
1693 return AE_CTRL_DEPTH;
1694
1695 acpi_scan_init_hotplug(device);
1696 acpi_device_dep_initialize(device);
1697
1698 out:
1699 if (!*return_value)
1700 *return_value = device;
1701
1702 return AE_OK;
1703 }
1704
1705 static int acpi_check_spi_i2c_slave(struct acpi_resource *ares, void *data)
1706 {
1707 bool *is_spi_i2c_slave_p = data;
1708
1709 if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
1710 return 1;
1711
1712 /*
1713 * devices that are connected to UART still need to be enumerated to
1714 * platform bus
1715 */
1716 if (ares->data.common_serial_bus.type != ACPI_RESOURCE_SERIAL_TYPE_UART)
1717 *is_spi_i2c_slave_p = true;
1718
1719 /* no need to do more checking */
1720 return -1;
1721 }
1722
1723 static void acpi_default_enumeration(struct acpi_device *device)
1724 {
1725 struct list_head resource_list;
1726 bool is_spi_i2c_slave = false;
1727
1728 /*
1729 * Do not enumerate SPI/I2C slaves as they will be enumerated by their
1730 * respective parents.
1731 */
1732 INIT_LIST_HEAD(&resource_list);
1733 acpi_dev_get_resources(device, &resource_list, acpi_check_spi_i2c_slave,
1734 &is_spi_i2c_slave);
1735 acpi_dev_free_resource_list(&resource_list);
1736 if (!is_spi_i2c_slave) {
1737 acpi_create_platform_device(device);
1738 acpi_device_set_enumerated(device);
1739 } else {
1740 blocking_notifier_call_chain(&acpi_reconfig_chain,
1741 ACPI_RECONFIG_DEVICE_ADD, device);
1742 }
1743 }
1744
1745 static const struct acpi_device_id generic_device_ids[] = {
1746 {ACPI_DT_NAMESPACE_HID, },
1747 {"", },
1748 };
1749
1750 static int acpi_generic_device_attach(struct acpi_device *adev,
1751 const struct acpi_device_id *not_used)
1752 {
1753 /*
1754 * Since ACPI_DT_NAMESPACE_HID is the only ID handled here, the test
1755 * below can be unconditional.
1756 */
1757 if (adev->data.of_compatible)
1758 acpi_default_enumeration(adev);
1759
1760 return 1;
1761 }
1762
1763 static struct acpi_scan_handler generic_device_handler = {
1764 .ids = generic_device_ids,
1765 .attach = acpi_generic_device_attach,
1766 };
1767
1768 static int acpi_scan_attach_handler(struct acpi_device *device)
1769 {
1770 struct acpi_hardware_id *hwid;
1771 int ret = 0;
1772
1773 list_for_each_entry(hwid, &device->pnp.ids, list) {
1774 const struct acpi_device_id *devid;
1775 struct acpi_scan_handler *handler;
1776
1777 handler = acpi_scan_match_handler(hwid->id, &devid);
1778 if (handler) {
1779 if (!handler->attach) {
1780 device->pnp.type.platform_id = 0;
1781 continue;
1782 }
1783 device->handler = handler;
1784 ret = handler->attach(device, devid);
1785 if (ret > 0)
1786 break;
1787
1788 device->handler = NULL;
1789 if (ret < 0)
1790 break;
1791 }
1792 }
1793
1794 return ret;
1795 }
1796
1797 static void acpi_bus_attach(struct acpi_device *device)
1798 {
1799 struct acpi_device *child;
1800 acpi_handle ejd;
1801 int ret;
1802
1803 if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
1804 register_dock_dependent_device(device, ejd);
1805
1806 acpi_bus_get_status(device);
1807 /* Skip devices that are not present. */
1808 if (!acpi_device_is_present(device)) {
1809 acpi_device_clear_enumerated(device);
1810 device->flags.power_manageable = 0;
1811 return;
1812 }
1813 if (device->handler)
1814 goto ok;
1815
1816 if (!device->flags.initialized) {
1817 device->flags.power_manageable =
1818 device->power.states[ACPI_STATE_D0].flags.valid;
1819 if (acpi_bus_init_power(device))
1820 device->flags.power_manageable = 0;
1821
1822 device->flags.initialized = true;
1823 }
1824
1825 ret = acpi_scan_attach_handler(device);
1826 if (ret < 0)
1827 return;
1828
1829 device->flags.match_driver = true;
1830 if (!ret) {
1831 ret = device_attach(&device->dev);
1832 if (ret < 0)
1833 return;
1834
1835 if (!ret && device->pnp.type.platform_id)
1836 acpi_default_enumeration(device);
1837 }
1838
1839 ok:
1840 list_for_each_entry(child, &device->children, node)
1841 acpi_bus_attach(child);
1842
1843 if (device->handler && device->handler->hotplug.notify_online)
1844 device->handler->hotplug.notify_online(device);
1845 }
1846
1847 void acpi_walk_dep_device_list(acpi_handle handle)
1848 {
1849 struct acpi_dep_data *dep, *tmp;
1850 struct acpi_device *adev;
1851
1852 mutex_lock(&acpi_dep_list_lock);
1853 list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
1854 if (dep->master == handle) {
1855 acpi_bus_get_device(dep->slave, &adev);
1856 if (!adev)
1857 continue;
1858
1859 adev->dep_unmet--;
1860 if (!adev->dep_unmet)
1861 acpi_bus_attach(adev);
1862 list_del(&dep->node);
1863 kfree(dep);
1864 }
1865 }
1866 mutex_unlock(&acpi_dep_list_lock);
1867 }
1868 EXPORT_SYMBOL_GPL(acpi_walk_dep_device_list);
1869
1870 /**
1871 * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
1872 * @handle: Root of the namespace scope to scan.
1873 *
1874 * Scan a given ACPI tree (probably recently hot-plugged) and create and add
1875 * found devices.
1876 *
1877 * If no devices were found, -ENODEV is returned, but it does not mean that
1878 * there has been a real error. There just have been no suitable ACPI objects
1879 * in the table trunk from which the kernel could create a device and add an
1880 * appropriate driver.
1881 *
1882 * Must be called under acpi_scan_lock.
1883 */
1884 int acpi_bus_scan(acpi_handle handle)
1885 {
1886 void *device = NULL;
1887
1888 if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
1889 acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
1890 acpi_bus_check_add, NULL, NULL, &device);
1891
1892 if (device) {
1893 acpi_bus_attach(device);
1894 return 0;
1895 }
1896 return -ENODEV;
1897 }
1898 EXPORT_SYMBOL(acpi_bus_scan);
1899
1900 /**
1901 * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
1902 * @adev: Root of the ACPI namespace scope to walk.
1903 *
1904 * Must be called under acpi_scan_lock.
1905 */
1906 void acpi_bus_trim(struct acpi_device *adev)
1907 {
1908 struct acpi_scan_handler *handler = adev->handler;
1909 struct acpi_device *child;
1910
1911 list_for_each_entry_reverse(child, &adev->children, node)
1912 acpi_bus_trim(child);
1913
1914 adev->flags.match_driver = false;
1915 if (handler) {
1916 if (handler->detach)
1917 handler->detach(adev);
1918
1919 adev->handler = NULL;
1920 } else {
1921 device_release_driver(&adev->dev);
1922 }
1923 /*
1924 * Most likely, the device is going away, so put it into D3cold before
1925 * that.
1926 */
1927 acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
1928 adev->flags.initialized = false;
1929 acpi_device_clear_enumerated(adev);
1930 }
1931 EXPORT_SYMBOL_GPL(acpi_bus_trim);
1932
1933 static int acpi_bus_scan_fixed(void)
1934 {
1935 int result = 0;
1936
1937 /*
1938 * Enumerate all fixed-feature devices.
1939 */
1940 if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
1941 struct acpi_device *device = NULL;
1942
1943 result = acpi_add_single_object(&device, NULL,
1944 ACPI_BUS_TYPE_POWER_BUTTON,
1945 ACPI_STA_DEFAULT);
1946 if (result)
1947 return result;
1948
1949 device->flags.match_driver = true;
1950 result = device_attach(&device->dev);
1951 if (result < 0)
1952 return result;
1953
1954 device_init_wakeup(&device->dev, true);
1955 }
1956
1957 if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
1958 struct acpi_device *device = NULL;
1959
1960 result = acpi_add_single_object(&device, NULL,
1961 ACPI_BUS_TYPE_SLEEP_BUTTON,
1962 ACPI_STA_DEFAULT);
1963 if (result)
1964 return result;
1965
1966 device->flags.match_driver = true;
1967 result = device_attach(&device->dev);
1968 }
1969
1970 return result < 0 ? result : 0;
1971 }
1972
1973 static void __init acpi_get_spcr_uart_addr(void)
1974 {
1975 acpi_status status;
1976 struct acpi_table_spcr *spcr_ptr;
1977
1978 status = acpi_get_table(ACPI_SIG_SPCR, 0,
1979 (struct acpi_table_header **)&spcr_ptr);
1980 if (ACPI_SUCCESS(status))
1981 spcr_uart_addr = spcr_ptr->serial_port.address;
1982 else
1983 printk(KERN_WARNING PREFIX "STAO table present, but SPCR is missing\n");
1984 }
1985
1986 static bool acpi_scan_initialized;
1987
1988 int __init acpi_scan_init(void)
1989 {
1990 int result;
1991 acpi_status status;
1992 struct acpi_table_stao *stao_ptr;
1993
1994 acpi_pci_root_init();
1995 acpi_pci_link_init();
1996 acpi_processor_init();
1997 acpi_lpss_init();
1998 acpi_apd_init();
1999 acpi_cmos_rtc_init();
2000 acpi_container_init();
2001 acpi_memory_hotplug_init();
2002 acpi_pnp_init();
2003 acpi_int340x_thermal_init();
2004 acpi_amba_init();
2005 acpi_watchdog_init();
2006
2007 acpi_scan_add_handler(&generic_device_handler);
2008
2009 /*
2010 * If there is STAO table, check whether it needs to ignore the UART
2011 * device in SPCR table.
2012 */
2013 status = acpi_get_table(ACPI_SIG_STAO, 0,
2014 (struct acpi_table_header **)&stao_ptr);
2015 if (ACPI_SUCCESS(status)) {
2016 if (stao_ptr->header.length > sizeof(struct acpi_table_stao))
2017 printk(KERN_INFO PREFIX "STAO Name List not yet supported.");
2018
2019 if (stao_ptr->ignore_uart)
2020 acpi_get_spcr_uart_addr();
2021 }
2022
2023 mutex_lock(&acpi_scan_lock);
2024 /*
2025 * Enumerate devices in the ACPI namespace.
2026 */
2027 result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2028 if (result)
2029 goto out;
2030
2031 result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2032 if (result)
2033 goto out;
2034
2035 /* Fixed feature devices do not exist on HW-reduced platform */
2036 if (!acpi_gbl_reduced_hardware) {
2037 result = acpi_bus_scan_fixed();
2038 if (result) {
2039 acpi_detach_data(acpi_root->handle,
2040 acpi_scan_drop_device);
2041 acpi_device_del(acpi_root);
2042 put_device(&acpi_root->dev);
2043 goto out;
2044 }
2045 }
2046
2047 acpi_update_all_gpes();
2048 acpi_ec_ecdt_start();
2049
2050 acpi_scan_initialized = true;
2051
2052 out:
2053 mutex_unlock(&acpi_scan_lock);
2054 return result;
2055 }
2056
2057 static struct acpi_probe_entry *ape;
2058 static int acpi_probe_count;
2059 static DEFINE_MUTEX(acpi_probe_mutex);
2060
2061 static int __init acpi_match_madt(struct acpi_subtable_header *header,
2062 const unsigned long end)
2063 {
2064 if (!ape->subtable_valid || ape->subtable_valid(header, ape))
2065 if (!ape->probe_subtbl(header, end))
2066 acpi_probe_count++;
2067
2068 return 0;
2069 }
2070
2071 int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr)
2072 {
2073 int count = 0;
2074
2075 if (acpi_disabled)
2076 return 0;
2077
2078 mutex_lock(&acpi_probe_mutex);
2079 for (ape = ap_head; nr; ape++, nr--) {
2080 if (ACPI_COMPARE_NAME(ACPI_SIG_MADT, ape->id)) {
2081 acpi_probe_count = 0;
2082 acpi_table_parse_madt(ape->type, acpi_match_madt, 0);
2083 count += acpi_probe_count;
2084 } else {
2085 int res;
2086 res = acpi_table_parse(ape->id, ape->probe_table);
2087 if (!res)
2088 count++;
2089 }
2090 }
2091 mutex_unlock(&acpi_probe_mutex);
2092
2093 return count;
2094 }
2095
2096 struct acpi_table_events_work {
2097 struct work_struct work;
2098 void *table;
2099 u32 event;
2100 };
2101
2102 static void acpi_table_events_fn(struct work_struct *work)
2103 {
2104 struct acpi_table_events_work *tew;
2105
2106 tew = container_of(work, struct acpi_table_events_work, work);
2107
2108 if (tew->event == ACPI_TABLE_EVENT_LOAD) {
2109 acpi_scan_lock_acquire();
2110 acpi_bus_scan(ACPI_ROOT_OBJECT);
2111 acpi_scan_lock_release();
2112 }
2113
2114 kfree(tew);
2115 }
2116
2117 void acpi_scan_table_handler(u32 event, void *table, void *context)
2118 {
2119 struct acpi_table_events_work *tew;
2120
2121 if (!acpi_scan_initialized)
2122 return;
2123
2124 if (event != ACPI_TABLE_EVENT_LOAD)
2125 return;
2126
2127 tew = kmalloc(sizeof(*tew), GFP_KERNEL);
2128 if (!tew)
2129 return;
2130
2131 INIT_WORK(&tew->work, acpi_table_events_fn);
2132 tew->table = table;
2133 tew->event = event;
2134
2135 schedule_work(&tew->work);
2136 }
2137
2138 int acpi_reconfig_notifier_register(struct notifier_block *nb)
2139 {
2140 return blocking_notifier_chain_register(&acpi_reconfig_chain, nb);
2141 }
2142 EXPORT_SYMBOL(acpi_reconfig_notifier_register);
2143
2144 int acpi_reconfig_notifier_unregister(struct notifier_block *nb)
2145 {
2146 return blocking_notifier_chain_unregister(&acpi_reconfig_chain, nb);
2147 }
2148 EXPORT_SYMBOL(acpi_reconfig_notifier_unregister);