xref: /linux/drivers/acpi/scan.c (revision 17cfcb68af3bc7d5e8ae08779b1853310a2949f3)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * scan.c - support for transforming the ACPI namespace into individual objects
4  */
5 
6 #include <linux/module.h>
7 #include <linux/init.h>
8 #include <linux/slab.h>
9 #include <linux/kernel.h>
10 #include <linux/acpi.h>
11 #include <linux/acpi_iort.h>
12 #include <linux/signal.h>
13 #include <linux/kthread.h>
14 #include <linux/dmi.h>
15 #include <linux/nls.h>
16 #include <linux/dma-mapping.h>
17 #include <linux/platform_data/x86/apple.h>
18 
19 #include <asm/pgtable.h>
20 
21 #include "internal.h"
22 
23 #define _COMPONENT		ACPI_BUS_COMPONENT
24 ACPI_MODULE_NAME("scan");
25 extern struct acpi_device *acpi_root;
26 
27 #define ACPI_BUS_CLASS			"system_bus"
28 #define ACPI_BUS_HID			"LNXSYBUS"
29 #define ACPI_BUS_DEVICE_NAME		"System Bus"
30 
31 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
32 
33 #define INVALID_ACPI_HANDLE	((acpi_handle)empty_zero_page)
34 
35 static const char *dummy_hid = "device";
36 
37 static LIST_HEAD(acpi_dep_list);
38 static DEFINE_MUTEX(acpi_dep_list_lock);
39 LIST_HEAD(acpi_bus_id_list);
40 static DEFINE_MUTEX(acpi_scan_lock);
41 static LIST_HEAD(acpi_scan_handlers_list);
42 DEFINE_MUTEX(acpi_device_lock);
43 LIST_HEAD(acpi_wakeup_device_list);
44 static DEFINE_MUTEX(acpi_hp_context_lock);
45 
46 /*
47  * The UART device described by the SPCR table is the only object which needs
48  * special-casing. Everything else is covered by ACPI namespace paths in STAO
49  * table.
50  */
51 static u64 spcr_uart_addr;
52 
53 struct acpi_dep_data {
54 	struct list_head node;
55 	acpi_handle master;
56 	acpi_handle slave;
57 };
58 
59 void acpi_scan_lock_acquire(void)
60 {
61 	mutex_lock(&acpi_scan_lock);
62 }
63 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
64 
65 void acpi_scan_lock_release(void)
66 {
67 	mutex_unlock(&acpi_scan_lock);
68 }
69 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
70 
71 void acpi_lock_hp_context(void)
72 {
73 	mutex_lock(&acpi_hp_context_lock);
74 }
75 
76 void acpi_unlock_hp_context(void)
77 {
78 	mutex_unlock(&acpi_hp_context_lock);
79 }
80 
81 void acpi_initialize_hp_context(struct acpi_device *adev,
82 				struct acpi_hotplug_context *hp,
83 				int (*notify)(struct acpi_device *, u32),
84 				void (*uevent)(struct acpi_device *, u32))
85 {
86 	acpi_lock_hp_context();
87 	hp->notify = notify;
88 	hp->uevent = uevent;
89 	acpi_set_hp_context(adev, hp);
90 	acpi_unlock_hp_context();
91 }
92 EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
93 
94 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
95 {
96 	if (!handler)
97 		return -EINVAL;
98 
99 	list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
100 	return 0;
101 }
102 
103 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
104 				       const char *hotplug_profile_name)
105 {
106 	int error;
107 
108 	error = acpi_scan_add_handler(handler);
109 	if (error)
110 		return error;
111 
112 	acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
113 	return 0;
114 }
115 
116 bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
117 {
118 	struct acpi_device_physical_node *pn;
119 	bool offline = true;
120 	char *envp[] = { "EVENT=offline", NULL };
121 
122 	/*
123 	 * acpi_container_offline() calls this for all of the container's
124 	 * children under the container's physical_node_lock lock.
125 	 */
126 	mutex_lock_nested(&adev->physical_node_lock, SINGLE_DEPTH_NESTING);
127 
128 	list_for_each_entry(pn, &adev->physical_node_list, node)
129 		if (device_supports_offline(pn->dev) && !pn->dev->offline) {
130 			if (uevent)
131 				kobject_uevent_env(&pn->dev->kobj, KOBJ_CHANGE, envp);
132 
133 			offline = false;
134 			break;
135 		}
136 
137 	mutex_unlock(&adev->physical_node_lock);
138 	return offline;
139 }
140 
141 static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
142 				    void **ret_p)
143 {
144 	struct acpi_device *device = NULL;
145 	struct acpi_device_physical_node *pn;
146 	bool second_pass = (bool)data;
147 	acpi_status status = AE_OK;
148 
149 	if (acpi_bus_get_device(handle, &device))
150 		return AE_OK;
151 
152 	if (device->handler && !device->handler->hotplug.enabled) {
153 		*ret_p = &device->dev;
154 		return AE_SUPPORT;
155 	}
156 
157 	mutex_lock(&device->physical_node_lock);
158 
159 	list_for_each_entry(pn, &device->physical_node_list, node) {
160 		int ret;
161 
162 		if (second_pass) {
163 			/* Skip devices offlined by the first pass. */
164 			if (pn->put_online)
165 				continue;
166 		} else {
167 			pn->put_online = false;
168 		}
169 		ret = device_offline(pn->dev);
170 		if (ret >= 0) {
171 			pn->put_online = !ret;
172 		} else {
173 			*ret_p = pn->dev;
174 			if (second_pass) {
175 				status = AE_ERROR;
176 				break;
177 			}
178 		}
179 	}
180 
181 	mutex_unlock(&device->physical_node_lock);
182 
183 	return status;
184 }
185 
186 static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
187 				   void **ret_p)
188 {
189 	struct acpi_device *device = NULL;
190 	struct acpi_device_physical_node *pn;
191 
192 	if (acpi_bus_get_device(handle, &device))
193 		return AE_OK;
194 
195 	mutex_lock(&device->physical_node_lock);
196 
197 	list_for_each_entry(pn, &device->physical_node_list, node)
198 		if (pn->put_online) {
199 			device_online(pn->dev);
200 			pn->put_online = false;
201 		}
202 
203 	mutex_unlock(&device->physical_node_lock);
204 
205 	return AE_OK;
206 }
207 
208 static int acpi_scan_try_to_offline(struct acpi_device *device)
209 {
210 	acpi_handle handle = device->handle;
211 	struct device *errdev = NULL;
212 	acpi_status status;
213 
214 	/*
215 	 * Carry out two passes here and ignore errors in the first pass,
216 	 * because if the devices in question are memory blocks and
217 	 * CONFIG_MEMCG is set, one of the blocks may hold data structures
218 	 * that the other blocks depend on, but it is not known in advance which
219 	 * block holds them.
220 	 *
221 	 * If the first pass is successful, the second one isn't needed, though.
222 	 */
223 	status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
224 				     NULL, acpi_bus_offline, (void *)false,
225 				     (void **)&errdev);
226 	if (status == AE_SUPPORT) {
227 		dev_warn(errdev, "Offline disabled.\n");
228 		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
229 				    acpi_bus_online, NULL, NULL, NULL);
230 		return -EPERM;
231 	}
232 	acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
233 	if (errdev) {
234 		errdev = NULL;
235 		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
236 				    NULL, acpi_bus_offline, (void *)true,
237 				    (void **)&errdev);
238 		if (!errdev)
239 			acpi_bus_offline(handle, 0, (void *)true,
240 					 (void **)&errdev);
241 
242 		if (errdev) {
243 			dev_warn(errdev, "Offline failed.\n");
244 			acpi_bus_online(handle, 0, NULL, NULL);
245 			acpi_walk_namespace(ACPI_TYPE_ANY, handle,
246 					    ACPI_UINT32_MAX, acpi_bus_online,
247 					    NULL, NULL, NULL);
248 			return -EBUSY;
249 		}
250 	}
251 	return 0;
252 }
253 
254 static int acpi_scan_hot_remove(struct acpi_device *device)
255 {
256 	acpi_handle handle = device->handle;
257 	unsigned long long sta;
258 	acpi_status status;
259 
260 	if (device->handler && device->handler->hotplug.demand_offline) {
261 		if (!acpi_scan_is_offline(device, true))
262 			return -EBUSY;
263 	} else {
264 		int error = acpi_scan_try_to_offline(device);
265 		if (error)
266 			return error;
267 	}
268 
269 	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
270 		"Hot-removing device %s...\n", dev_name(&device->dev)));
271 
272 	acpi_bus_trim(device);
273 
274 	acpi_evaluate_lck(handle, 0);
275 	/*
276 	 * TBD: _EJD support.
277 	 */
278 	status = acpi_evaluate_ej0(handle);
279 	if (status == AE_NOT_FOUND)
280 		return -ENODEV;
281 	else if (ACPI_FAILURE(status))
282 		return -EIO;
283 
284 	/*
285 	 * Verify if eject was indeed successful.  If not, log an error
286 	 * message.  No need to call _OST since _EJ0 call was made OK.
287 	 */
288 	status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
289 	if (ACPI_FAILURE(status)) {
290 		acpi_handle_warn(handle,
291 			"Status check after eject failed (0x%x)\n", status);
292 	} else if (sta & ACPI_STA_DEVICE_ENABLED) {
293 		acpi_handle_warn(handle,
294 			"Eject incomplete - status 0x%llx\n", sta);
295 	}
296 
297 	return 0;
298 }
299 
300 static int acpi_scan_device_not_present(struct acpi_device *adev)
301 {
302 	if (!acpi_device_enumerated(adev)) {
303 		dev_warn(&adev->dev, "Still not present\n");
304 		return -EALREADY;
305 	}
306 	acpi_bus_trim(adev);
307 	return 0;
308 }
309 
310 static int acpi_scan_device_check(struct acpi_device *adev)
311 {
312 	int error;
313 
314 	acpi_bus_get_status(adev);
315 	if (adev->status.present || adev->status.functional) {
316 		/*
317 		 * This function is only called for device objects for which
318 		 * matching scan handlers exist.  The only situation in which
319 		 * the scan handler is not attached to this device object yet
320 		 * is when the device has just appeared (either it wasn't
321 		 * present at all before or it was removed and then added
322 		 * again).
323 		 */
324 		if (adev->handler) {
325 			dev_warn(&adev->dev, "Already enumerated\n");
326 			return -EALREADY;
327 		}
328 		error = acpi_bus_scan(adev->handle);
329 		if (error) {
330 			dev_warn(&adev->dev, "Namespace scan failure\n");
331 			return error;
332 		}
333 		if (!adev->handler) {
334 			dev_warn(&adev->dev, "Enumeration failure\n");
335 			error = -ENODEV;
336 		}
337 	} else {
338 		error = acpi_scan_device_not_present(adev);
339 	}
340 	return error;
341 }
342 
343 static int acpi_scan_bus_check(struct acpi_device *adev)
344 {
345 	struct acpi_scan_handler *handler = adev->handler;
346 	struct acpi_device *child;
347 	int error;
348 
349 	acpi_bus_get_status(adev);
350 	if (!(adev->status.present || adev->status.functional)) {
351 		acpi_scan_device_not_present(adev);
352 		return 0;
353 	}
354 	if (handler && handler->hotplug.scan_dependent)
355 		return handler->hotplug.scan_dependent(adev);
356 
357 	error = acpi_bus_scan(adev->handle);
358 	if (error) {
359 		dev_warn(&adev->dev, "Namespace scan failure\n");
360 		return error;
361 	}
362 	list_for_each_entry(child, &adev->children, node) {
363 		error = acpi_scan_bus_check(child);
364 		if (error)
365 			return error;
366 	}
367 	return 0;
368 }
369 
370 static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type)
371 {
372 	switch (type) {
373 	case ACPI_NOTIFY_BUS_CHECK:
374 		return acpi_scan_bus_check(adev);
375 	case ACPI_NOTIFY_DEVICE_CHECK:
376 		return acpi_scan_device_check(adev);
377 	case ACPI_NOTIFY_EJECT_REQUEST:
378 	case ACPI_OST_EC_OSPM_EJECT:
379 		if (adev->handler && !adev->handler->hotplug.enabled) {
380 			dev_info(&adev->dev, "Eject disabled\n");
381 			return -EPERM;
382 		}
383 		acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST,
384 				  ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
385 		return acpi_scan_hot_remove(adev);
386 	}
387 	return -EINVAL;
388 }
389 
390 void acpi_device_hotplug(struct acpi_device *adev, u32 src)
391 {
392 	u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
393 	int error = -ENODEV;
394 
395 	lock_device_hotplug();
396 	mutex_lock(&acpi_scan_lock);
397 
398 	/*
399 	 * The device object's ACPI handle cannot become invalid as long as we
400 	 * are holding acpi_scan_lock, but it might have become invalid before
401 	 * that lock was acquired.
402 	 */
403 	if (adev->handle == INVALID_ACPI_HANDLE)
404 		goto err_out;
405 
406 	if (adev->flags.is_dock_station) {
407 		error = dock_notify(adev, src);
408 	} else if (adev->flags.hotplug_notify) {
409 		error = acpi_generic_hotplug_event(adev, src);
410 	} else {
411 		int (*notify)(struct acpi_device *, u32);
412 
413 		acpi_lock_hp_context();
414 		notify = adev->hp ? adev->hp->notify : NULL;
415 		acpi_unlock_hp_context();
416 		/*
417 		 * There may be additional notify handlers for device objects
418 		 * without the .event() callback, so ignore them here.
419 		 */
420 		if (notify)
421 			error = notify(adev, src);
422 		else
423 			goto out;
424 	}
425 	switch (error) {
426 	case 0:
427 		ost_code = ACPI_OST_SC_SUCCESS;
428 		break;
429 	case -EPERM:
430 		ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
431 		break;
432 	case -EBUSY:
433 		ost_code = ACPI_OST_SC_DEVICE_BUSY;
434 		break;
435 	default:
436 		ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
437 		break;
438 	}
439 
440  err_out:
441 	acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
442 
443  out:
444 	acpi_bus_put_acpi_device(adev);
445 	mutex_unlock(&acpi_scan_lock);
446 	unlock_device_hotplug();
447 }
448 
449 static void acpi_free_power_resources_lists(struct acpi_device *device)
450 {
451 	int i;
452 
453 	if (device->wakeup.flags.valid)
454 		acpi_power_resources_list_free(&device->wakeup.resources);
455 
456 	if (!device->power.flags.power_resources)
457 		return;
458 
459 	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
460 		struct acpi_device_power_state *ps = &device->power.states[i];
461 		acpi_power_resources_list_free(&ps->resources);
462 	}
463 }
464 
465 static void acpi_device_release(struct device *dev)
466 {
467 	struct acpi_device *acpi_dev = to_acpi_device(dev);
468 
469 	acpi_free_properties(acpi_dev);
470 	acpi_free_pnp_ids(&acpi_dev->pnp);
471 	acpi_free_power_resources_lists(acpi_dev);
472 	kfree(acpi_dev);
473 }
474 
475 static void acpi_device_del(struct acpi_device *device)
476 {
477 	struct acpi_device_bus_id *acpi_device_bus_id;
478 
479 	mutex_lock(&acpi_device_lock);
480 	if (device->parent)
481 		list_del(&device->node);
482 
483 	list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node)
484 		if (!strcmp(acpi_device_bus_id->bus_id,
485 			    acpi_device_hid(device))) {
486 			if (acpi_device_bus_id->instance_no > 0)
487 				acpi_device_bus_id->instance_no--;
488 			else {
489 				list_del(&acpi_device_bus_id->node);
490 				kfree(acpi_device_bus_id);
491 			}
492 			break;
493 		}
494 
495 	list_del(&device->wakeup_list);
496 	mutex_unlock(&acpi_device_lock);
497 
498 	acpi_power_add_remove_device(device, false);
499 	acpi_device_remove_files(device);
500 	if (device->remove)
501 		device->remove(device);
502 
503 	device_del(&device->dev);
504 }
505 
506 static BLOCKING_NOTIFIER_HEAD(acpi_reconfig_chain);
507 
508 static LIST_HEAD(acpi_device_del_list);
509 static DEFINE_MUTEX(acpi_device_del_lock);
510 
511 static void acpi_device_del_work_fn(struct work_struct *work_not_used)
512 {
513 	for (;;) {
514 		struct acpi_device *adev;
515 
516 		mutex_lock(&acpi_device_del_lock);
517 
518 		if (list_empty(&acpi_device_del_list)) {
519 			mutex_unlock(&acpi_device_del_lock);
520 			break;
521 		}
522 		adev = list_first_entry(&acpi_device_del_list,
523 					struct acpi_device, del_list);
524 		list_del(&adev->del_list);
525 
526 		mutex_unlock(&acpi_device_del_lock);
527 
528 		blocking_notifier_call_chain(&acpi_reconfig_chain,
529 					     ACPI_RECONFIG_DEVICE_REMOVE, adev);
530 
531 		acpi_device_del(adev);
532 		/*
533 		 * Drop references to all power resources that might have been
534 		 * used by the device.
535 		 */
536 		acpi_power_transition(adev, ACPI_STATE_D3_COLD);
537 		put_device(&adev->dev);
538 	}
539 }
540 
541 /**
542  * acpi_scan_drop_device - Drop an ACPI device object.
543  * @handle: Handle of an ACPI namespace node, not used.
544  * @context: Address of the ACPI device object to drop.
545  *
546  * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
547  * namespace node the device object pointed to by @context is attached to.
548  *
549  * The unregistration is carried out asynchronously to avoid running
550  * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
551  * ensure the correct ordering (the device objects must be unregistered in the
552  * same order in which the corresponding namespace nodes are deleted).
553  */
554 static void acpi_scan_drop_device(acpi_handle handle, void *context)
555 {
556 	static DECLARE_WORK(work, acpi_device_del_work_fn);
557 	struct acpi_device *adev = context;
558 
559 	mutex_lock(&acpi_device_del_lock);
560 
561 	/*
562 	 * Use the ACPI hotplug workqueue which is ordered, so this work item
563 	 * won't run after any hotplug work items submitted subsequently.  That
564 	 * prevents attempts to register device objects identical to those being
565 	 * deleted from happening concurrently (such attempts result from
566 	 * hotplug events handled via the ACPI hotplug workqueue).  It also will
567 	 * run after all of the work items submitted previosuly, which helps
568 	 * those work items to ensure that they are not accessing stale device
569 	 * objects.
570 	 */
571 	if (list_empty(&acpi_device_del_list))
572 		acpi_queue_hotplug_work(&work);
573 
574 	list_add_tail(&adev->del_list, &acpi_device_del_list);
575 	/* Make acpi_ns_validate_handle() return NULL for this handle. */
576 	adev->handle = INVALID_ACPI_HANDLE;
577 
578 	mutex_unlock(&acpi_device_del_lock);
579 }
580 
581 static int acpi_get_device_data(acpi_handle handle, struct acpi_device **device,
582 				void (*callback)(void *))
583 {
584 	acpi_status status;
585 
586 	if (!device)
587 		return -EINVAL;
588 
589 	status = acpi_get_data_full(handle, acpi_scan_drop_device,
590 				    (void **)device, callback);
591 	if (ACPI_FAILURE(status) || !*device) {
592 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
593 				  handle));
594 		return -ENODEV;
595 	}
596 	return 0;
597 }
598 
599 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
600 {
601 	return acpi_get_device_data(handle, device, NULL);
602 }
603 EXPORT_SYMBOL(acpi_bus_get_device);
604 
605 static void get_acpi_device(void *dev)
606 {
607 	if (dev)
608 		get_device(&((struct acpi_device *)dev)->dev);
609 }
610 
611 struct acpi_device *acpi_bus_get_acpi_device(acpi_handle handle)
612 {
613 	struct acpi_device *adev = NULL;
614 
615 	acpi_get_device_data(handle, &adev, get_acpi_device);
616 	return adev;
617 }
618 
619 void acpi_bus_put_acpi_device(struct acpi_device *adev)
620 {
621 	put_device(&adev->dev);
622 }
623 
624 int acpi_device_add(struct acpi_device *device,
625 		    void (*release)(struct device *))
626 {
627 	int result;
628 	struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
629 	int found = 0;
630 
631 	if (device->handle) {
632 		acpi_status status;
633 
634 		status = acpi_attach_data(device->handle, acpi_scan_drop_device,
635 					  device);
636 		if (ACPI_FAILURE(status)) {
637 			acpi_handle_err(device->handle,
638 					"Unable to attach device data\n");
639 			return -ENODEV;
640 		}
641 	}
642 
643 	/*
644 	 * Linkage
645 	 * -------
646 	 * Link this device to its parent and siblings.
647 	 */
648 	INIT_LIST_HEAD(&device->children);
649 	INIT_LIST_HEAD(&device->node);
650 	INIT_LIST_HEAD(&device->wakeup_list);
651 	INIT_LIST_HEAD(&device->physical_node_list);
652 	INIT_LIST_HEAD(&device->del_list);
653 	mutex_init(&device->physical_node_lock);
654 
655 	new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
656 	if (!new_bus_id) {
657 		pr_err(PREFIX "Memory allocation error\n");
658 		result = -ENOMEM;
659 		goto err_detach;
660 	}
661 
662 	mutex_lock(&acpi_device_lock);
663 	/*
664 	 * Find suitable bus_id and instance number in acpi_bus_id_list
665 	 * If failed, create one and link it into acpi_bus_id_list
666 	 */
667 	list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
668 		if (!strcmp(acpi_device_bus_id->bus_id,
669 			    acpi_device_hid(device))) {
670 			acpi_device_bus_id->instance_no++;
671 			found = 1;
672 			kfree(new_bus_id);
673 			break;
674 		}
675 	}
676 	if (!found) {
677 		acpi_device_bus_id = new_bus_id;
678 		strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
679 		acpi_device_bus_id->instance_no = 0;
680 		list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
681 	}
682 	dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
683 
684 	if (device->parent)
685 		list_add_tail(&device->node, &device->parent->children);
686 
687 	if (device->wakeup.flags.valid)
688 		list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
689 	mutex_unlock(&acpi_device_lock);
690 
691 	if (device->parent)
692 		device->dev.parent = &device->parent->dev;
693 	device->dev.bus = &acpi_bus_type;
694 	device->dev.release = release;
695 	result = device_add(&device->dev);
696 	if (result) {
697 		dev_err(&device->dev, "Error registering device\n");
698 		goto err;
699 	}
700 
701 	result = acpi_device_setup_files(device);
702 	if (result)
703 		printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
704 		       dev_name(&device->dev));
705 
706 	return 0;
707 
708  err:
709 	mutex_lock(&acpi_device_lock);
710 	if (device->parent)
711 		list_del(&device->node);
712 	list_del(&device->wakeup_list);
713 	mutex_unlock(&acpi_device_lock);
714 
715  err_detach:
716 	acpi_detach_data(device->handle, acpi_scan_drop_device);
717 	return result;
718 }
719 
720 /* --------------------------------------------------------------------------
721                                  Device Enumeration
722    -------------------------------------------------------------------------- */
723 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
724 {
725 	struct acpi_device *device = NULL;
726 	acpi_status status;
727 
728 	/*
729 	 * Fixed hardware devices do not appear in the namespace and do not
730 	 * have handles, but we fabricate acpi_devices for them, so we have
731 	 * to deal with them specially.
732 	 */
733 	if (!handle)
734 		return acpi_root;
735 
736 	do {
737 		status = acpi_get_parent(handle, &handle);
738 		if (ACPI_FAILURE(status))
739 			return status == AE_NULL_ENTRY ? NULL : acpi_root;
740 	} while (acpi_bus_get_device(handle, &device));
741 	return device;
742 }
743 
744 acpi_status
745 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
746 {
747 	acpi_status status;
748 	acpi_handle tmp;
749 	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
750 	union acpi_object *obj;
751 
752 	status = acpi_get_handle(handle, "_EJD", &tmp);
753 	if (ACPI_FAILURE(status))
754 		return status;
755 
756 	status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
757 	if (ACPI_SUCCESS(status)) {
758 		obj = buffer.pointer;
759 		status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
760 					 ejd);
761 		kfree(buffer.pointer);
762 	}
763 	return status;
764 }
765 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
766 
767 static int acpi_bus_extract_wakeup_device_power_package(struct acpi_device *dev)
768 {
769 	acpi_handle handle = dev->handle;
770 	struct acpi_device_wakeup *wakeup = &dev->wakeup;
771 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
772 	union acpi_object *package = NULL;
773 	union acpi_object *element = NULL;
774 	acpi_status status;
775 	int err = -ENODATA;
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 bool acpi_wakeup_gpe_init(struct acpi_device *device)
848 {
849 	static const struct acpi_device_id button_device_ids[] = {
850 		{"PNP0C0C", 0},		/* Power button */
851 		{"PNP0C0D", 0},		/* Lid */
852 		{"PNP0C0E", 0},		/* Sleep button */
853 		{"", 0},
854 	};
855 	struct acpi_device_wakeup *wakeup = &device->wakeup;
856 	acpi_status status;
857 
858 	wakeup->flags.notifier_present = 0;
859 
860 	/* Power button, Lid switch always enable wakeup */
861 	if (!acpi_match_device_ids(device, button_device_ids)) {
862 		if (!acpi_match_device_ids(device, &button_device_ids[1])) {
863 			/* Do not use Lid/sleep button for S5 wakeup */
864 			if (wakeup->sleep_state == ACPI_STATE_S5)
865 				wakeup->sleep_state = ACPI_STATE_S4;
866 		}
867 		acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
868 		device_set_wakeup_capable(&device->dev, true);
869 		return true;
870 	}
871 
872 	status = acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
873 					 wakeup->gpe_number);
874 	return ACPI_SUCCESS(status);
875 }
876 
877 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
878 {
879 	int err;
880 
881 	/* Presence of _PRW indicates wake capable */
882 	if (!acpi_has_method(device->handle, "_PRW"))
883 		return;
884 
885 	err = acpi_bus_extract_wakeup_device_power_package(device);
886 	if (err) {
887 		dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
888 		return;
889 	}
890 
891 	device->wakeup.flags.valid = acpi_wakeup_gpe_init(device);
892 	device->wakeup.prepare_count = 0;
893 	/*
894 	 * Call _PSW/_DSW object to disable its ability to wake the sleeping
895 	 * system for the ACPI device with the _PRW object.
896 	 * The _PSW object is deprecated in ACPI 3.0 and is replaced by _DSW.
897 	 * So it is necessary to call _DSW object first. Only when it is not
898 	 * present will the _PSW object used.
899 	 */
900 	err = acpi_device_sleep_wake(device, 0, 0, 0);
901 	if (err)
902 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
903 				"error in _DSW or _PSW evaluation\n"));
904 }
905 
906 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
907 {
908 	struct acpi_device_power_state *ps = &device->power.states[state];
909 	char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
910 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
911 	acpi_status status;
912 
913 	INIT_LIST_HEAD(&ps->resources);
914 
915 	/* Evaluate "_PRx" to get referenced power resources */
916 	status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
917 	if (ACPI_SUCCESS(status)) {
918 		union acpi_object *package = buffer.pointer;
919 
920 		if (buffer.length && package
921 		    && package->type == ACPI_TYPE_PACKAGE
922 		    && package->package.count) {
923 			int err = acpi_extract_power_resources(package, 0,
924 							       &ps->resources);
925 			if (!err)
926 				device->power.flags.power_resources = 1;
927 		}
928 		ACPI_FREE(buffer.pointer);
929 	}
930 
931 	/* Evaluate "_PSx" to see if we can do explicit sets */
932 	pathname[2] = 'S';
933 	if (acpi_has_method(device->handle, pathname))
934 		ps->flags.explicit_set = 1;
935 
936 	/* State is valid if there are means to put the device into it. */
937 	if (!list_empty(&ps->resources) || ps->flags.explicit_set)
938 		ps->flags.valid = 1;
939 
940 	ps->power = -1;		/* Unknown - driver assigned */
941 	ps->latency = -1;	/* Unknown - driver assigned */
942 }
943 
944 static void acpi_bus_get_power_flags(struct acpi_device *device)
945 {
946 	u32 i;
947 
948 	/* Presence of _PS0|_PR0 indicates 'power manageable' */
949 	if (!acpi_has_method(device->handle, "_PS0") &&
950 	    !acpi_has_method(device->handle, "_PR0"))
951 		return;
952 
953 	device->flags.power_manageable = 1;
954 
955 	/*
956 	 * Power Management Flags
957 	 */
958 	if (acpi_has_method(device->handle, "_PSC"))
959 		device->power.flags.explicit_get = 1;
960 
961 	if (acpi_has_method(device->handle, "_IRC"))
962 		device->power.flags.inrush_current = 1;
963 
964 	if (acpi_has_method(device->handle, "_DSW"))
965 		device->power.flags.dsw_present = 1;
966 
967 	/*
968 	 * Enumerate supported power management states
969 	 */
970 	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
971 		acpi_bus_init_power_state(device, i);
972 
973 	INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
974 	if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources))
975 		device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
976 
977 	/* Set defaults for D0 and D3hot states (always valid) */
978 	device->power.states[ACPI_STATE_D0].flags.valid = 1;
979 	device->power.states[ACPI_STATE_D0].power = 100;
980 	device->power.states[ACPI_STATE_D3_HOT].flags.valid = 1;
981 
982 	if (acpi_bus_init_power(device))
983 		device->flags.power_manageable = 0;
984 }
985 
986 static void acpi_bus_get_flags(struct acpi_device *device)
987 {
988 	/* Presence of _STA indicates 'dynamic_status' */
989 	if (acpi_has_method(device->handle, "_STA"))
990 		device->flags.dynamic_status = 1;
991 
992 	/* Presence of _RMV indicates 'removable' */
993 	if (acpi_has_method(device->handle, "_RMV"))
994 		device->flags.removable = 1;
995 
996 	/* Presence of _EJD|_EJ0 indicates 'ejectable' */
997 	if (acpi_has_method(device->handle, "_EJD") ||
998 	    acpi_has_method(device->handle, "_EJ0"))
999 		device->flags.ejectable = 1;
1000 }
1001 
1002 static void acpi_device_get_busid(struct acpi_device *device)
1003 {
1004 	char bus_id[5] = { '?', 0 };
1005 	struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1006 	int i = 0;
1007 
1008 	/*
1009 	 * Bus ID
1010 	 * ------
1011 	 * The device's Bus ID is simply the object name.
1012 	 * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1013 	 */
1014 	if (ACPI_IS_ROOT_DEVICE(device)) {
1015 		strcpy(device->pnp.bus_id, "ACPI");
1016 		return;
1017 	}
1018 
1019 	switch (device->device_type) {
1020 	case ACPI_BUS_TYPE_POWER_BUTTON:
1021 		strcpy(device->pnp.bus_id, "PWRF");
1022 		break;
1023 	case ACPI_BUS_TYPE_SLEEP_BUTTON:
1024 		strcpy(device->pnp.bus_id, "SLPF");
1025 		break;
1026 	case ACPI_BUS_TYPE_ECDT_EC:
1027 		strcpy(device->pnp.bus_id, "ECDT");
1028 		break;
1029 	default:
1030 		acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1031 		/* Clean up trailing underscores (if any) */
1032 		for (i = 3; i > 1; i--) {
1033 			if (bus_id[i] == '_')
1034 				bus_id[i] = '\0';
1035 			else
1036 				break;
1037 		}
1038 		strcpy(device->pnp.bus_id, bus_id);
1039 		break;
1040 	}
1041 }
1042 
1043 /*
1044  * acpi_ata_match - see if an acpi object is an ATA device
1045  *
1046  * If an acpi object has one of the ACPI ATA methods defined,
1047  * then we can safely call it an ATA device.
1048  */
1049 bool acpi_ata_match(acpi_handle handle)
1050 {
1051 	return acpi_has_method(handle, "_GTF") ||
1052 	       acpi_has_method(handle, "_GTM") ||
1053 	       acpi_has_method(handle, "_STM") ||
1054 	       acpi_has_method(handle, "_SDD");
1055 }
1056 
1057 /*
1058  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1059  *
1060  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1061  * then we can safely call it an ejectable drive bay
1062  */
1063 bool acpi_bay_match(acpi_handle handle)
1064 {
1065 	acpi_handle phandle;
1066 
1067 	if (!acpi_has_method(handle, "_EJ0"))
1068 		return false;
1069 	if (acpi_ata_match(handle))
1070 		return true;
1071 	if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1072 		return false;
1073 
1074 	return acpi_ata_match(phandle);
1075 }
1076 
1077 bool acpi_device_is_battery(struct acpi_device *adev)
1078 {
1079 	struct acpi_hardware_id *hwid;
1080 
1081 	list_for_each_entry(hwid, &adev->pnp.ids, list)
1082 		if (!strcmp("PNP0C0A", hwid->id))
1083 			return true;
1084 
1085 	return false;
1086 }
1087 
1088 static bool is_ejectable_bay(struct acpi_device *adev)
1089 {
1090 	acpi_handle handle = adev->handle;
1091 
1092 	if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
1093 		return true;
1094 
1095 	return acpi_bay_match(handle);
1096 }
1097 
1098 /*
1099  * acpi_dock_match - see if an acpi object has a _DCK method
1100  */
1101 bool acpi_dock_match(acpi_handle handle)
1102 {
1103 	return acpi_has_method(handle, "_DCK");
1104 }
1105 
1106 static acpi_status
1107 acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
1108 			  void **return_value)
1109 {
1110 	long *cap = context;
1111 
1112 	if (acpi_has_method(handle, "_BCM") &&
1113 	    acpi_has_method(handle, "_BCL")) {
1114 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight "
1115 				  "support\n"));
1116 		*cap |= ACPI_VIDEO_BACKLIGHT;
1117 		/* We have backlight support, no need to scan further */
1118 		return AE_CTRL_TERMINATE;
1119 	}
1120 	return 0;
1121 }
1122 
1123 /* Returns true if the ACPI object is a video device which can be
1124  * handled by video.ko.
1125  * The device will get a Linux specific CID added in scan.c to
1126  * identify the device as an ACPI graphics device
1127  * Be aware that the graphics device may not be physically present
1128  * Use acpi_video_get_capabilities() to detect general ACPI video
1129  * capabilities of present cards
1130  */
1131 long acpi_is_video_device(acpi_handle handle)
1132 {
1133 	long video_caps = 0;
1134 
1135 	/* Is this device able to support video switching ? */
1136 	if (acpi_has_method(handle, "_DOD") || acpi_has_method(handle, "_DOS"))
1137 		video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
1138 
1139 	/* Is this device able to retrieve a video ROM ? */
1140 	if (acpi_has_method(handle, "_ROM"))
1141 		video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
1142 
1143 	/* Is this device able to configure which video head to be POSTed ? */
1144 	if (acpi_has_method(handle, "_VPO") &&
1145 	    acpi_has_method(handle, "_GPD") &&
1146 	    acpi_has_method(handle, "_SPD"))
1147 		video_caps |= ACPI_VIDEO_DEVICE_POSTING;
1148 
1149 	/* Only check for backlight functionality if one of the above hit. */
1150 	if (video_caps)
1151 		acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
1152 				    ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
1153 				    &video_caps, NULL);
1154 
1155 	return video_caps;
1156 }
1157 EXPORT_SYMBOL(acpi_is_video_device);
1158 
1159 const char *acpi_device_hid(struct acpi_device *device)
1160 {
1161 	struct acpi_hardware_id *hid;
1162 
1163 	if (list_empty(&device->pnp.ids))
1164 		return dummy_hid;
1165 
1166 	hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1167 	return hid->id;
1168 }
1169 EXPORT_SYMBOL(acpi_device_hid);
1170 
1171 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1172 {
1173 	struct acpi_hardware_id *id;
1174 
1175 	id = kmalloc(sizeof(*id), GFP_KERNEL);
1176 	if (!id)
1177 		return;
1178 
1179 	id->id = kstrdup_const(dev_id, GFP_KERNEL);
1180 	if (!id->id) {
1181 		kfree(id);
1182 		return;
1183 	}
1184 
1185 	list_add_tail(&id->list, &pnp->ids);
1186 	pnp->type.hardware_id = 1;
1187 }
1188 
1189 /*
1190  * Old IBM workstations have a DSDT bug wherein the SMBus object
1191  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1192  * prefix.  Work around this.
1193  */
1194 static bool acpi_ibm_smbus_match(acpi_handle handle)
1195 {
1196 	char node_name[ACPI_PATH_SEGMENT_LENGTH];
1197 	struct acpi_buffer path = { sizeof(node_name), node_name };
1198 
1199 	if (!dmi_name_in_vendors("IBM"))
1200 		return false;
1201 
1202 	/* Look for SMBS object */
1203 	if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1204 	    strcmp("SMBS", path.pointer))
1205 		return false;
1206 
1207 	/* Does it have the necessary (but misnamed) methods? */
1208 	if (acpi_has_method(handle, "SBI") &&
1209 	    acpi_has_method(handle, "SBR") &&
1210 	    acpi_has_method(handle, "SBW"))
1211 		return true;
1212 
1213 	return false;
1214 }
1215 
1216 static bool acpi_object_is_system_bus(acpi_handle handle)
1217 {
1218 	acpi_handle tmp;
1219 
1220 	if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
1221 	    tmp == handle)
1222 		return true;
1223 	if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
1224 	    tmp == handle)
1225 		return true;
1226 
1227 	return false;
1228 }
1229 
1230 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1231 				int device_type)
1232 {
1233 	acpi_status status;
1234 	struct acpi_device_info *info;
1235 	struct acpi_pnp_device_id_list *cid_list;
1236 	int i;
1237 
1238 	switch (device_type) {
1239 	case ACPI_BUS_TYPE_DEVICE:
1240 		if (handle == ACPI_ROOT_OBJECT) {
1241 			acpi_add_id(pnp, ACPI_SYSTEM_HID);
1242 			break;
1243 		}
1244 
1245 		status = acpi_get_object_info(handle, &info);
1246 		if (ACPI_FAILURE(status)) {
1247 			pr_err(PREFIX "%s: Error reading device info\n",
1248 					__func__);
1249 			return;
1250 		}
1251 
1252 		if (info->valid & ACPI_VALID_HID) {
1253 			acpi_add_id(pnp, info->hardware_id.string);
1254 			pnp->type.platform_id = 1;
1255 		}
1256 		if (info->valid & ACPI_VALID_CID) {
1257 			cid_list = &info->compatible_id_list;
1258 			for (i = 0; i < cid_list->count; i++)
1259 				acpi_add_id(pnp, cid_list->ids[i].string);
1260 		}
1261 		if (info->valid & ACPI_VALID_ADR) {
1262 			pnp->bus_address = info->address;
1263 			pnp->type.bus_address = 1;
1264 		}
1265 		if (info->valid & ACPI_VALID_UID)
1266 			pnp->unique_id = kstrdup(info->unique_id.string,
1267 							GFP_KERNEL);
1268 		if (info->valid & ACPI_VALID_CLS)
1269 			acpi_add_id(pnp, info->class_code.string);
1270 
1271 		kfree(info);
1272 
1273 		/*
1274 		 * Some devices don't reliably have _HIDs & _CIDs, so add
1275 		 * synthetic HIDs to make sure drivers can find them.
1276 		 */
1277 		if (acpi_is_video_device(handle))
1278 			acpi_add_id(pnp, ACPI_VIDEO_HID);
1279 		else if (acpi_bay_match(handle))
1280 			acpi_add_id(pnp, ACPI_BAY_HID);
1281 		else if (acpi_dock_match(handle))
1282 			acpi_add_id(pnp, ACPI_DOCK_HID);
1283 		else if (acpi_ibm_smbus_match(handle))
1284 			acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1285 		else if (list_empty(&pnp->ids) &&
1286 			 acpi_object_is_system_bus(handle)) {
1287 			/* \_SB, \_TZ, LNXSYBUS */
1288 			acpi_add_id(pnp, ACPI_BUS_HID);
1289 			strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1290 			strcpy(pnp->device_class, ACPI_BUS_CLASS);
1291 		}
1292 
1293 		break;
1294 	case ACPI_BUS_TYPE_POWER:
1295 		acpi_add_id(pnp, ACPI_POWER_HID);
1296 		break;
1297 	case ACPI_BUS_TYPE_PROCESSOR:
1298 		acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1299 		break;
1300 	case ACPI_BUS_TYPE_THERMAL:
1301 		acpi_add_id(pnp, ACPI_THERMAL_HID);
1302 		break;
1303 	case ACPI_BUS_TYPE_POWER_BUTTON:
1304 		acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1305 		break;
1306 	case ACPI_BUS_TYPE_SLEEP_BUTTON:
1307 		acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1308 		break;
1309 	case ACPI_BUS_TYPE_ECDT_EC:
1310 		acpi_add_id(pnp, ACPI_ECDT_HID);
1311 		break;
1312 	}
1313 }
1314 
1315 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1316 {
1317 	struct acpi_hardware_id *id, *tmp;
1318 
1319 	list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1320 		kfree_const(id->id);
1321 		kfree(id);
1322 	}
1323 	kfree(pnp->unique_id);
1324 }
1325 
1326 /**
1327  * acpi_dma_supported - Check DMA support for the specified device.
1328  * @adev: The pointer to acpi device
1329  *
1330  * Return false if DMA is not supported. Otherwise, return true
1331  */
1332 bool acpi_dma_supported(struct acpi_device *adev)
1333 {
1334 	if (!adev)
1335 		return false;
1336 
1337 	if (adev->flags.cca_seen)
1338 		return true;
1339 
1340 	/*
1341 	* Per ACPI 6.0 sec 6.2.17, assume devices can do cache-coherent
1342 	* DMA on "Intel platforms".  Presumably that includes all x86 and
1343 	* ia64, and other arches will set CONFIG_ACPI_CCA_REQUIRED=y.
1344 	*/
1345 	if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1346 		return true;
1347 
1348 	return false;
1349 }
1350 
1351 /**
1352  * acpi_get_dma_attr - Check the supported DMA attr for the specified device.
1353  * @adev: The pointer to acpi device
1354  *
1355  * Return enum dev_dma_attr.
1356  */
1357 enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
1358 {
1359 	if (!acpi_dma_supported(adev))
1360 		return DEV_DMA_NOT_SUPPORTED;
1361 
1362 	if (adev->flags.coherent_dma)
1363 		return DEV_DMA_COHERENT;
1364 	else
1365 		return DEV_DMA_NON_COHERENT;
1366 }
1367 
1368 /**
1369  * acpi_dma_get_range() - Get device DMA parameters.
1370  *
1371  * @dev: device to configure
1372  * @dma_addr: pointer device DMA address result
1373  * @offset: pointer to the DMA offset result
1374  * @size: pointer to DMA range size result
1375  *
1376  * Evaluate DMA regions and return respectively DMA region start, offset
1377  * and size in dma_addr, offset and size on parsing success; it does not
1378  * update the passed in values on failure.
1379  *
1380  * Return 0 on success, < 0 on failure.
1381  */
1382 int acpi_dma_get_range(struct device *dev, u64 *dma_addr, u64 *offset,
1383 		       u64 *size)
1384 {
1385 	struct acpi_device *adev;
1386 	LIST_HEAD(list);
1387 	struct resource_entry *rentry;
1388 	int ret;
1389 	struct device *dma_dev = dev;
1390 	u64 len, dma_start = U64_MAX, dma_end = 0, dma_offset = 0;
1391 
1392 	/*
1393 	 * Walk the device tree chasing an ACPI companion with a _DMA
1394 	 * object while we go. Stop if we find a device with an ACPI
1395 	 * companion containing a _DMA method.
1396 	 */
1397 	do {
1398 		adev = ACPI_COMPANION(dma_dev);
1399 		if (adev && acpi_has_method(adev->handle, METHOD_NAME__DMA))
1400 			break;
1401 
1402 		dma_dev = dma_dev->parent;
1403 	} while (dma_dev);
1404 
1405 	if (!dma_dev)
1406 		return -ENODEV;
1407 
1408 	if (!acpi_has_method(adev->handle, METHOD_NAME__CRS)) {
1409 		acpi_handle_warn(adev->handle, "_DMA is valid only if _CRS is present\n");
1410 		return -EINVAL;
1411 	}
1412 
1413 	ret = acpi_dev_get_dma_resources(adev, &list);
1414 	if (ret > 0) {
1415 		list_for_each_entry(rentry, &list, node) {
1416 			if (dma_offset && rentry->offset != dma_offset) {
1417 				ret = -EINVAL;
1418 				dev_warn(dma_dev, "Can't handle multiple windows with different offsets\n");
1419 				goto out;
1420 			}
1421 			dma_offset = rentry->offset;
1422 
1423 			/* Take lower and upper limits */
1424 			if (rentry->res->start < dma_start)
1425 				dma_start = rentry->res->start;
1426 			if (rentry->res->end > dma_end)
1427 				dma_end = rentry->res->end;
1428 		}
1429 
1430 		if (dma_start >= dma_end) {
1431 			ret = -EINVAL;
1432 			dev_dbg(dma_dev, "Invalid DMA regions configuration\n");
1433 			goto out;
1434 		}
1435 
1436 		*dma_addr = dma_start - dma_offset;
1437 		len = dma_end - dma_start;
1438 		*size = max(len, len + 1);
1439 		*offset = dma_offset;
1440 	}
1441  out:
1442 	acpi_dev_free_resource_list(&list);
1443 
1444 	return ret >= 0 ? 0 : ret;
1445 }
1446 
1447 /**
1448  * acpi_dma_configure - Set-up DMA configuration for the device.
1449  * @dev: The pointer to the device
1450  * @attr: device dma attributes
1451  */
1452 int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr)
1453 {
1454 	const struct iommu_ops *iommu;
1455 	u64 dma_addr = 0, size = 0;
1456 
1457 	if (attr == DEV_DMA_NOT_SUPPORTED) {
1458 		set_dma_ops(dev, &dma_dummy_ops);
1459 		return 0;
1460 	}
1461 
1462 	iort_dma_setup(dev, &dma_addr, &size);
1463 
1464 	iommu = iort_iommu_configure(dev);
1465 	if (IS_ERR(iommu) && PTR_ERR(iommu) == -EPROBE_DEFER)
1466 		return -EPROBE_DEFER;
1467 
1468 	arch_setup_dma_ops(dev, dma_addr, size,
1469 				iommu, attr == DEV_DMA_COHERENT);
1470 
1471 	return 0;
1472 }
1473 EXPORT_SYMBOL_GPL(acpi_dma_configure);
1474 
1475 static void acpi_init_coherency(struct acpi_device *adev)
1476 {
1477 	unsigned long long cca = 0;
1478 	acpi_status status;
1479 	struct acpi_device *parent = adev->parent;
1480 
1481 	if (parent && parent->flags.cca_seen) {
1482 		/*
1483 		 * From ACPI spec, OSPM will ignore _CCA if an ancestor
1484 		 * already saw one.
1485 		 */
1486 		adev->flags.cca_seen = 1;
1487 		cca = parent->flags.coherent_dma;
1488 	} else {
1489 		status = acpi_evaluate_integer(adev->handle, "_CCA",
1490 					       NULL, &cca);
1491 		if (ACPI_SUCCESS(status))
1492 			adev->flags.cca_seen = 1;
1493 		else if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1494 			/*
1495 			 * If architecture does not specify that _CCA is
1496 			 * required for DMA-able devices (e.g. x86),
1497 			 * we default to _CCA=1.
1498 			 */
1499 			cca = 1;
1500 		else
1501 			acpi_handle_debug(adev->handle,
1502 					  "ACPI device is missing _CCA.\n");
1503 	}
1504 
1505 	adev->flags.coherent_dma = cca;
1506 }
1507 
1508 static int acpi_check_serial_bus_slave(struct acpi_resource *ares, void *data)
1509 {
1510 	bool *is_serial_bus_slave_p = data;
1511 
1512 	if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
1513 		return 1;
1514 
1515 	*is_serial_bus_slave_p = true;
1516 
1517 	 /* no need to do more checking */
1518 	return -1;
1519 }
1520 
1521 static bool acpi_is_indirect_io_slave(struct acpi_device *device)
1522 {
1523 	struct acpi_device *parent = device->parent;
1524 	static const struct acpi_device_id indirect_io_hosts[] = {
1525 		{"HISI0191", 0},
1526 		{}
1527 	};
1528 
1529 	return parent && !acpi_match_device_ids(parent, indirect_io_hosts);
1530 }
1531 
1532 static bool acpi_device_enumeration_by_parent(struct acpi_device *device)
1533 {
1534 	struct list_head resource_list;
1535 	bool is_serial_bus_slave = false;
1536 	/*
1537 	 * These devices have multiple I2cSerialBus resources and an i2c-client
1538 	 * must be instantiated for each, each with its own i2c_device_id.
1539 	 * Normally we only instantiate an i2c-client for the first resource,
1540 	 * using the ACPI HID as id. These special cases are handled by the
1541 	 * drivers/platform/x86/i2c-multi-instantiate.c driver, which knows
1542 	 * which i2c_device_id to use for each resource.
1543 	 */
1544 	static const struct acpi_device_id i2c_multi_instantiate_ids[] = {
1545 		{"BSG1160", },
1546 		{"BSG2150", },
1547 		{"INT33FE", },
1548 		{"INT3515", },
1549 		{}
1550 	};
1551 
1552 	if (acpi_is_indirect_io_slave(device))
1553 		return true;
1554 
1555 	/* Macs use device properties in lieu of _CRS resources */
1556 	if (x86_apple_machine &&
1557 	    (fwnode_property_present(&device->fwnode, "spiSclkPeriod") ||
1558 	     fwnode_property_present(&device->fwnode, "i2cAddress") ||
1559 	     fwnode_property_present(&device->fwnode, "baud")))
1560 		return true;
1561 
1562 	/* Instantiate a pdev for the i2c-multi-instantiate drv to bind to */
1563 	if (!acpi_match_device_ids(device, i2c_multi_instantiate_ids))
1564 		return false;
1565 
1566 	INIT_LIST_HEAD(&resource_list);
1567 	acpi_dev_get_resources(device, &resource_list,
1568 			       acpi_check_serial_bus_slave,
1569 			       &is_serial_bus_slave);
1570 	acpi_dev_free_resource_list(&resource_list);
1571 
1572 	return is_serial_bus_slave;
1573 }
1574 
1575 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1576 			     int type, unsigned long long sta)
1577 {
1578 	INIT_LIST_HEAD(&device->pnp.ids);
1579 	device->device_type = type;
1580 	device->handle = handle;
1581 	device->parent = acpi_bus_get_parent(handle);
1582 	device->fwnode.ops = &acpi_device_fwnode_ops;
1583 	acpi_set_device_status(device, sta);
1584 	acpi_device_get_busid(device);
1585 	acpi_set_pnp_ids(handle, &device->pnp, type);
1586 	acpi_init_properties(device);
1587 	acpi_bus_get_flags(device);
1588 	device->flags.match_driver = false;
1589 	device->flags.initialized = true;
1590 	device->flags.enumeration_by_parent =
1591 		acpi_device_enumeration_by_parent(device);
1592 	acpi_device_clear_enumerated(device);
1593 	device_initialize(&device->dev);
1594 	dev_set_uevent_suppress(&device->dev, true);
1595 	acpi_init_coherency(device);
1596 	/* Assume there are unmet deps until acpi_device_dep_initialize() runs */
1597 	device->dep_unmet = 1;
1598 }
1599 
1600 void acpi_device_add_finalize(struct acpi_device *device)
1601 {
1602 	dev_set_uevent_suppress(&device->dev, false);
1603 	kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1604 }
1605 
1606 static int acpi_add_single_object(struct acpi_device **child,
1607 				  acpi_handle handle, int type,
1608 				  unsigned long long sta)
1609 {
1610 	int result;
1611 	struct acpi_device *device;
1612 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1613 
1614 	device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1615 	if (!device) {
1616 		printk(KERN_ERR PREFIX "Memory allocation error\n");
1617 		return -ENOMEM;
1618 	}
1619 
1620 	acpi_init_device_object(device, handle, type, sta);
1621 	/*
1622 	 * For ACPI_BUS_TYPE_DEVICE getting the status is delayed till here so
1623 	 * that we can call acpi_bus_get_status() and use its quirk handling.
1624 	 * Note this must be done before the get power-/wakeup_dev-flags calls.
1625 	 */
1626 	if (type == ACPI_BUS_TYPE_DEVICE)
1627 		if (acpi_bus_get_status(device) < 0)
1628 			acpi_set_device_status(device, 0);
1629 
1630 	acpi_bus_get_power_flags(device);
1631 	acpi_bus_get_wakeup_device_flags(device);
1632 
1633 	result = acpi_device_add(device, acpi_device_release);
1634 	if (result) {
1635 		acpi_device_release(&device->dev);
1636 		return result;
1637 	}
1638 
1639 	acpi_power_add_remove_device(device, true);
1640 	acpi_device_add_finalize(device);
1641 	acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1642 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1643 		dev_name(&device->dev), (char *) buffer.pointer,
1644 		device->parent ? dev_name(&device->parent->dev) : "(null)"));
1645 	kfree(buffer.pointer);
1646 	*child = device;
1647 	return 0;
1648 }
1649 
1650 static acpi_status acpi_get_resource_memory(struct acpi_resource *ares,
1651 					    void *context)
1652 {
1653 	struct resource *res = context;
1654 
1655 	if (acpi_dev_resource_memory(ares, res))
1656 		return AE_CTRL_TERMINATE;
1657 
1658 	return AE_OK;
1659 }
1660 
1661 static bool acpi_device_should_be_hidden(acpi_handle handle)
1662 {
1663 	acpi_status status;
1664 	struct resource res;
1665 
1666 	/* Check if it should ignore the UART device */
1667 	if (!(spcr_uart_addr && acpi_has_method(handle, METHOD_NAME__CRS)))
1668 		return false;
1669 
1670 	/*
1671 	 * The UART device described in SPCR table is assumed to have only one
1672 	 * memory resource present. So we only look for the first one here.
1673 	 */
1674 	status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1675 				     acpi_get_resource_memory, &res);
1676 	if (ACPI_FAILURE(status) || res.start != spcr_uart_addr)
1677 		return false;
1678 
1679 	acpi_handle_info(handle, "The UART device @%pa in SPCR table will be hidden\n",
1680 			 &res.start);
1681 
1682 	return true;
1683 }
1684 
1685 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1686 				    unsigned long long *sta)
1687 {
1688 	acpi_status status;
1689 	acpi_object_type acpi_type;
1690 
1691 	status = acpi_get_type(handle, &acpi_type);
1692 	if (ACPI_FAILURE(status))
1693 		return -ENODEV;
1694 
1695 	switch (acpi_type) {
1696 	case ACPI_TYPE_ANY:		/* for ACPI_ROOT_OBJECT */
1697 	case ACPI_TYPE_DEVICE:
1698 		if (acpi_device_should_be_hidden(handle))
1699 			return -ENODEV;
1700 
1701 		*type = ACPI_BUS_TYPE_DEVICE;
1702 		/*
1703 		 * acpi_add_single_object updates this once we've an acpi_device
1704 		 * so that acpi_bus_get_status' quirk handling can be used.
1705 		 */
1706 		*sta = ACPI_STA_DEFAULT;
1707 		break;
1708 	case ACPI_TYPE_PROCESSOR:
1709 		*type = ACPI_BUS_TYPE_PROCESSOR;
1710 		status = acpi_bus_get_status_handle(handle, sta);
1711 		if (ACPI_FAILURE(status))
1712 			return -ENODEV;
1713 		break;
1714 	case ACPI_TYPE_THERMAL:
1715 		*type = ACPI_BUS_TYPE_THERMAL;
1716 		*sta = ACPI_STA_DEFAULT;
1717 		break;
1718 	case ACPI_TYPE_POWER:
1719 		*type = ACPI_BUS_TYPE_POWER;
1720 		*sta = ACPI_STA_DEFAULT;
1721 		break;
1722 	default:
1723 		return -ENODEV;
1724 	}
1725 
1726 	return 0;
1727 }
1728 
1729 bool acpi_device_is_present(const struct acpi_device *adev)
1730 {
1731 	return adev->status.present || adev->status.functional;
1732 }
1733 
1734 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1735 				       const char *idstr,
1736 				       const struct acpi_device_id **matchid)
1737 {
1738 	const struct acpi_device_id *devid;
1739 
1740 	if (handler->match)
1741 		return handler->match(idstr, matchid);
1742 
1743 	for (devid = handler->ids; devid->id[0]; devid++)
1744 		if (!strcmp((char *)devid->id, idstr)) {
1745 			if (matchid)
1746 				*matchid = devid;
1747 
1748 			return true;
1749 		}
1750 
1751 	return false;
1752 }
1753 
1754 static struct acpi_scan_handler *acpi_scan_match_handler(const char *idstr,
1755 					const struct acpi_device_id **matchid)
1756 {
1757 	struct acpi_scan_handler *handler;
1758 
1759 	list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1760 		if (acpi_scan_handler_matching(handler, idstr, matchid))
1761 			return handler;
1762 
1763 	return NULL;
1764 }
1765 
1766 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1767 {
1768 	if (!!hotplug->enabled == !!val)
1769 		return;
1770 
1771 	mutex_lock(&acpi_scan_lock);
1772 
1773 	hotplug->enabled = val;
1774 
1775 	mutex_unlock(&acpi_scan_lock);
1776 }
1777 
1778 static void acpi_scan_init_hotplug(struct acpi_device *adev)
1779 {
1780 	struct acpi_hardware_id *hwid;
1781 
1782 	if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
1783 		acpi_dock_add(adev);
1784 		return;
1785 	}
1786 	list_for_each_entry(hwid, &adev->pnp.ids, list) {
1787 		struct acpi_scan_handler *handler;
1788 
1789 		handler = acpi_scan_match_handler(hwid->id, NULL);
1790 		if (handler) {
1791 			adev->flags.hotplug_notify = true;
1792 			break;
1793 		}
1794 	}
1795 }
1796 
1797 static void acpi_device_dep_initialize(struct acpi_device *adev)
1798 {
1799 	struct acpi_dep_data *dep;
1800 	struct acpi_handle_list dep_devices;
1801 	acpi_status status;
1802 	int i;
1803 
1804 	adev->dep_unmet = 0;
1805 
1806 	if (!acpi_has_method(adev->handle, "_DEP"))
1807 		return;
1808 
1809 	status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
1810 					&dep_devices);
1811 	if (ACPI_FAILURE(status)) {
1812 		dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
1813 		return;
1814 	}
1815 
1816 	for (i = 0; i < dep_devices.count; i++) {
1817 		struct acpi_device_info *info;
1818 		int skip;
1819 
1820 		status = acpi_get_object_info(dep_devices.handles[i], &info);
1821 		if (ACPI_FAILURE(status)) {
1822 			dev_dbg(&adev->dev, "Error reading _DEP device info\n");
1823 			continue;
1824 		}
1825 
1826 		/*
1827 		 * Skip the dependency of Windows System Power
1828 		 * Management Controller
1829 		 */
1830 		skip = info->valid & ACPI_VALID_HID &&
1831 			!strcmp(info->hardware_id.string, "INT3396");
1832 
1833 		kfree(info);
1834 
1835 		if (skip)
1836 			continue;
1837 
1838 		dep = kzalloc(sizeof(struct acpi_dep_data), GFP_KERNEL);
1839 		if (!dep)
1840 			return;
1841 
1842 		dep->master = dep_devices.handles[i];
1843 		dep->slave  = adev->handle;
1844 		adev->dep_unmet++;
1845 
1846 		mutex_lock(&acpi_dep_list_lock);
1847 		list_add_tail(&dep->node , &acpi_dep_list);
1848 		mutex_unlock(&acpi_dep_list_lock);
1849 	}
1850 }
1851 
1852 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
1853 				      void *not_used, void **return_value)
1854 {
1855 	struct acpi_device *device = NULL;
1856 	int type;
1857 	unsigned long long sta;
1858 	int result;
1859 
1860 	acpi_bus_get_device(handle, &device);
1861 	if (device)
1862 		goto out;
1863 
1864 	result = acpi_bus_type_and_status(handle, &type, &sta);
1865 	if (result)
1866 		return AE_OK;
1867 
1868 	if (type == ACPI_BUS_TYPE_POWER) {
1869 		acpi_add_power_resource(handle);
1870 		return AE_OK;
1871 	}
1872 
1873 	acpi_add_single_object(&device, handle, type, sta);
1874 	if (!device)
1875 		return AE_CTRL_DEPTH;
1876 
1877 	acpi_scan_init_hotplug(device);
1878 	acpi_device_dep_initialize(device);
1879 
1880  out:
1881 	if (!*return_value)
1882 		*return_value = device;
1883 
1884 	return AE_OK;
1885 }
1886 
1887 static void acpi_default_enumeration(struct acpi_device *device)
1888 {
1889 	/*
1890 	 * Do not enumerate devices with enumeration_by_parent flag set as
1891 	 * they will be enumerated by their respective parents.
1892 	 */
1893 	if (!device->flags.enumeration_by_parent) {
1894 		acpi_create_platform_device(device, NULL);
1895 		acpi_device_set_enumerated(device);
1896 	} else {
1897 		blocking_notifier_call_chain(&acpi_reconfig_chain,
1898 					     ACPI_RECONFIG_DEVICE_ADD, device);
1899 	}
1900 }
1901 
1902 static const struct acpi_device_id generic_device_ids[] = {
1903 	{ACPI_DT_NAMESPACE_HID, },
1904 	{"", },
1905 };
1906 
1907 static int acpi_generic_device_attach(struct acpi_device *adev,
1908 				      const struct acpi_device_id *not_used)
1909 {
1910 	/*
1911 	 * Since ACPI_DT_NAMESPACE_HID is the only ID handled here, the test
1912 	 * below can be unconditional.
1913 	 */
1914 	if (adev->data.of_compatible)
1915 		acpi_default_enumeration(adev);
1916 
1917 	return 1;
1918 }
1919 
1920 static struct acpi_scan_handler generic_device_handler = {
1921 	.ids = generic_device_ids,
1922 	.attach = acpi_generic_device_attach,
1923 };
1924 
1925 static int acpi_scan_attach_handler(struct acpi_device *device)
1926 {
1927 	struct acpi_hardware_id *hwid;
1928 	int ret = 0;
1929 
1930 	list_for_each_entry(hwid, &device->pnp.ids, list) {
1931 		const struct acpi_device_id *devid;
1932 		struct acpi_scan_handler *handler;
1933 
1934 		handler = acpi_scan_match_handler(hwid->id, &devid);
1935 		if (handler) {
1936 			if (!handler->attach) {
1937 				device->pnp.type.platform_id = 0;
1938 				continue;
1939 			}
1940 			device->handler = handler;
1941 			ret = handler->attach(device, devid);
1942 			if (ret > 0)
1943 				break;
1944 
1945 			device->handler = NULL;
1946 			if (ret < 0)
1947 				break;
1948 		}
1949 	}
1950 
1951 	return ret;
1952 }
1953 
1954 static void acpi_bus_attach(struct acpi_device *device)
1955 {
1956 	struct acpi_device *child;
1957 	acpi_handle ejd;
1958 	int ret;
1959 
1960 	if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
1961 		register_dock_dependent_device(device, ejd);
1962 
1963 	acpi_bus_get_status(device);
1964 	/* Skip devices that are not present. */
1965 	if (!acpi_device_is_present(device)) {
1966 		device->flags.initialized = false;
1967 		acpi_device_clear_enumerated(device);
1968 		device->flags.power_manageable = 0;
1969 		return;
1970 	}
1971 	if (device->handler)
1972 		goto ok;
1973 
1974 	if (!device->flags.initialized) {
1975 		device->flags.power_manageable =
1976 			device->power.states[ACPI_STATE_D0].flags.valid;
1977 		if (acpi_bus_init_power(device))
1978 			device->flags.power_manageable = 0;
1979 
1980 		device->flags.initialized = true;
1981 	} else if (device->flags.visited) {
1982 		goto ok;
1983 	}
1984 
1985 	ret = acpi_scan_attach_handler(device);
1986 	if (ret < 0)
1987 		return;
1988 
1989 	device->flags.match_driver = true;
1990 	if (ret > 0 && !device->flags.enumeration_by_parent) {
1991 		acpi_device_set_enumerated(device);
1992 		goto ok;
1993 	}
1994 
1995 	ret = device_attach(&device->dev);
1996 	if (ret < 0)
1997 		return;
1998 
1999 	if (device->pnp.type.platform_id || device->flags.enumeration_by_parent)
2000 		acpi_default_enumeration(device);
2001 	else
2002 		acpi_device_set_enumerated(device);
2003 
2004  ok:
2005 	list_for_each_entry(child, &device->children, node)
2006 		acpi_bus_attach(child);
2007 
2008 	if (device->handler && device->handler->hotplug.notify_online)
2009 		device->handler->hotplug.notify_online(device);
2010 }
2011 
2012 void acpi_walk_dep_device_list(acpi_handle handle)
2013 {
2014 	struct acpi_dep_data *dep, *tmp;
2015 	struct acpi_device *adev;
2016 
2017 	mutex_lock(&acpi_dep_list_lock);
2018 	list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
2019 		if (dep->master == handle) {
2020 			acpi_bus_get_device(dep->slave, &adev);
2021 			if (!adev)
2022 				continue;
2023 
2024 			adev->dep_unmet--;
2025 			if (!adev->dep_unmet)
2026 				acpi_bus_attach(adev);
2027 			list_del(&dep->node);
2028 			kfree(dep);
2029 		}
2030 	}
2031 	mutex_unlock(&acpi_dep_list_lock);
2032 }
2033 EXPORT_SYMBOL_GPL(acpi_walk_dep_device_list);
2034 
2035 /**
2036  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
2037  * @handle: Root of the namespace scope to scan.
2038  *
2039  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
2040  * found devices.
2041  *
2042  * If no devices were found, -ENODEV is returned, but it does not mean that
2043  * there has been a real error.  There just have been no suitable ACPI objects
2044  * in the table trunk from which the kernel could create a device and add an
2045  * appropriate driver.
2046  *
2047  * Must be called under acpi_scan_lock.
2048  */
2049 int acpi_bus_scan(acpi_handle handle)
2050 {
2051 	void *device = NULL;
2052 
2053 	if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
2054 		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2055 				    acpi_bus_check_add, NULL, NULL, &device);
2056 
2057 	if (device) {
2058 		acpi_bus_attach(device);
2059 		return 0;
2060 	}
2061 	return -ENODEV;
2062 }
2063 EXPORT_SYMBOL(acpi_bus_scan);
2064 
2065 /**
2066  * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
2067  * @adev: Root of the ACPI namespace scope to walk.
2068  *
2069  * Must be called under acpi_scan_lock.
2070  */
2071 void acpi_bus_trim(struct acpi_device *adev)
2072 {
2073 	struct acpi_scan_handler *handler = adev->handler;
2074 	struct acpi_device *child;
2075 
2076 	list_for_each_entry_reverse(child, &adev->children, node)
2077 		acpi_bus_trim(child);
2078 
2079 	adev->flags.match_driver = false;
2080 	if (handler) {
2081 		if (handler->detach)
2082 			handler->detach(adev);
2083 
2084 		adev->handler = NULL;
2085 	} else {
2086 		device_release_driver(&adev->dev);
2087 	}
2088 	/*
2089 	 * Most likely, the device is going away, so put it into D3cold before
2090 	 * that.
2091 	 */
2092 	acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
2093 	adev->flags.initialized = false;
2094 	acpi_device_clear_enumerated(adev);
2095 }
2096 EXPORT_SYMBOL_GPL(acpi_bus_trim);
2097 
2098 int acpi_bus_register_early_device(int type)
2099 {
2100 	struct acpi_device *device = NULL;
2101 	int result;
2102 
2103 	result = acpi_add_single_object(&device, NULL,
2104 					type, ACPI_STA_DEFAULT);
2105 	if (result)
2106 		return result;
2107 
2108 	device->flags.match_driver = true;
2109 	return device_attach(&device->dev);
2110 }
2111 EXPORT_SYMBOL_GPL(acpi_bus_register_early_device);
2112 
2113 static int acpi_bus_scan_fixed(void)
2114 {
2115 	int result = 0;
2116 
2117 	/*
2118 	 * Enumerate all fixed-feature devices.
2119 	 */
2120 	if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2121 		struct acpi_device *device = NULL;
2122 
2123 		result = acpi_add_single_object(&device, NULL,
2124 						ACPI_BUS_TYPE_POWER_BUTTON,
2125 						ACPI_STA_DEFAULT);
2126 		if (result)
2127 			return result;
2128 
2129 		device->flags.match_driver = true;
2130 		result = device_attach(&device->dev);
2131 		if (result < 0)
2132 			return result;
2133 
2134 		device_init_wakeup(&device->dev, true);
2135 	}
2136 
2137 	if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2138 		struct acpi_device *device = NULL;
2139 
2140 		result = acpi_add_single_object(&device, NULL,
2141 						ACPI_BUS_TYPE_SLEEP_BUTTON,
2142 						ACPI_STA_DEFAULT);
2143 		if (result)
2144 			return result;
2145 
2146 		device->flags.match_driver = true;
2147 		result = device_attach(&device->dev);
2148 	}
2149 
2150 	return result < 0 ? result : 0;
2151 }
2152 
2153 static void __init acpi_get_spcr_uart_addr(void)
2154 {
2155 	acpi_status status;
2156 	struct acpi_table_spcr *spcr_ptr;
2157 
2158 	status = acpi_get_table(ACPI_SIG_SPCR, 0,
2159 				(struct acpi_table_header **)&spcr_ptr);
2160 	if (ACPI_SUCCESS(status))
2161 		spcr_uart_addr = spcr_ptr->serial_port.address;
2162 	else
2163 		printk(KERN_WARNING PREFIX "STAO table present, but SPCR is missing\n");
2164 }
2165 
2166 static bool acpi_scan_initialized;
2167 
2168 int __init acpi_scan_init(void)
2169 {
2170 	int result;
2171 	acpi_status status;
2172 	struct acpi_table_stao *stao_ptr;
2173 
2174 	acpi_pci_root_init();
2175 	acpi_pci_link_init();
2176 	acpi_processor_init();
2177 	acpi_lpss_init();
2178 	acpi_apd_init();
2179 	acpi_cmos_rtc_init();
2180 	acpi_container_init();
2181 	acpi_memory_hotplug_init();
2182 	acpi_watchdog_init();
2183 	acpi_pnp_init();
2184 	acpi_int340x_thermal_init();
2185 	acpi_amba_init();
2186 	acpi_init_lpit();
2187 
2188 	acpi_scan_add_handler(&generic_device_handler);
2189 
2190 	/*
2191 	 * If there is STAO table, check whether it needs to ignore the UART
2192 	 * device in SPCR table.
2193 	 */
2194 	status = acpi_get_table(ACPI_SIG_STAO, 0,
2195 				(struct acpi_table_header **)&stao_ptr);
2196 	if (ACPI_SUCCESS(status)) {
2197 		if (stao_ptr->header.length > sizeof(struct acpi_table_stao))
2198 			printk(KERN_INFO PREFIX "STAO Name List not yet supported.");
2199 
2200 		if (stao_ptr->ignore_uart)
2201 			acpi_get_spcr_uart_addr();
2202 	}
2203 
2204 	acpi_gpe_apply_masked_gpes();
2205 	acpi_update_all_gpes();
2206 
2207 	/*
2208 	 * Although we call __add_memory() that is documented to require the
2209 	 * device_hotplug_lock, it is not necessary here because this is an
2210 	 * early code when userspace or any other code path cannot trigger
2211 	 * hotplug/hotunplug operations.
2212 	 */
2213 	mutex_lock(&acpi_scan_lock);
2214 	/*
2215 	 * Enumerate devices in the ACPI namespace.
2216 	 */
2217 	result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2218 	if (result)
2219 		goto out;
2220 
2221 	result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2222 	if (result)
2223 		goto out;
2224 
2225 	/* Fixed feature devices do not exist on HW-reduced platform */
2226 	if (!acpi_gbl_reduced_hardware) {
2227 		result = acpi_bus_scan_fixed();
2228 		if (result) {
2229 			acpi_detach_data(acpi_root->handle,
2230 					 acpi_scan_drop_device);
2231 			acpi_device_del(acpi_root);
2232 			put_device(&acpi_root->dev);
2233 			goto out;
2234 		}
2235 	}
2236 
2237 	acpi_scan_initialized = true;
2238 
2239  out:
2240 	mutex_unlock(&acpi_scan_lock);
2241 	return result;
2242 }
2243 
2244 static struct acpi_probe_entry *ape;
2245 static int acpi_probe_count;
2246 static DEFINE_MUTEX(acpi_probe_mutex);
2247 
2248 static int __init acpi_match_madt(union acpi_subtable_headers *header,
2249 				  const unsigned long end)
2250 {
2251 	if (!ape->subtable_valid || ape->subtable_valid(&header->common, ape))
2252 		if (!ape->probe_subtbl(header, end))
2253 			acpi_probe_count++;
2254 
2255 	return 0;
2256 }
2257 
2258 int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr)
2259 {
2260 	int count = 0;
2261 
2262 	if (acpi_disabled)
2263 		return 0;
2264 
2265 	mutex_lock(&acpi_probe_mutex);
2266 	for (ape = ap_head; nr; ape++, nr--) {
2267 		if (ACPI_COMPARE_NAMESEG(ACPI_SIG_MADT, ape->id)) {
2268 			acpi_probe_count = 0;
2269 			acpi_table_parse_madt(ape->type, acpi_match_madt, 0);
2270 			count += acpi_probe_count;
2271 		} else {
2272 			int res;
2273 			res = acpi_table_parse(ape->id, ape->probe_table);
2274 			if (!res)
2275 				count++;
2276 		}
2277 	}
2278 	mutex_unlock(&acpi_probe_mutex);
2279 
2280 	return count;
2281 }
2282 
2283 struct acpi_table_events_work {
2284 	struct work_struct work;
2285 	void *table;
2286 	u32 event;
2287 };
2288 
2289 static void acpi_table_events_fn(struct work_struct *work)
2290 {
2291 	struct acpi_table_events_work *tew;
2292 
2293 	tew = container_of(work, struct acpi_table_events_work, work);
2294 
2295 	if (tew->event == ACPI_TABLE_EVENT_LOAD) {
2296 		acpi_scan_lock_acquire();
2297 		acpi_bus_scan(ACPI_ROOT_OBJECT);
2298 		acpi_scan_lock_release();
2299 	}
2300 
2301 	kfree(tew);
2302 }
2303 
2304 void acpi_scan_table_handler(u32 event, void *table, void *context)
2305 {
2306 	struct acpi_table_events_work *tew;
2307 
2308 	if (!acpi_scan_initialized)
2309 		return;
2310 
2311 	if (event != ACPI_TABLE_EVENT_LOAD)
2312 		return;
2313 
2314 	tew = kmalloc(sizeof(*tew), GFP_KERNEL);
2315 	if (!tew)
2316 		return;
2317 
2318 	INIT_WORK(&tew->work, acpi_table_events_fn);
2319 	tew->table = table;
2320 	tew->event = event;
2321 
2322 	schedule_work(&tew->work);
2323 }
2324 
2325 int acpi_reconfig_notifier_register(struct notifier_block *nb)
2326 {
2327 	return blocking_notifier_chain_register(&acpi_reconfig_chain, nb);
2328 }
2329 EXPORT_SYMBOL(acpi_reconfig_notifier_register);
2330 
2331 int acpi_reconfig_notifier_unregister(struct notifier_block *nb)
2332 {
2333 	return blocking_notifier_chain_unregister(&acpi_reconfig_chain, nb);
2334 }
2335 EXPORT_SYMBOL(acpi_reconfig_notifier_unregister);
2336