xref: /openbmc/linux/drivers/acpi/scan.c (revision aa6159ab)
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-map-ops.h>
17 #include <linux/platform_data/x86/apple.h>
18 #include <linux/pgtable.h>
19 
20 #include "internal.h"
21 
22 #define _COMPONENT		ACPI_BUS_COMPONENT
23 ACPI_MODULE_NAME("scan");
24 extern struct acpi_device *acpi_root;
25 
26 #define ACPI_BUS_CLASS			"system_bus"
27 #define ACPI_BUS_HID			"LNXSYBUS"
28 #define ACPI_BUS_DEVICE_NAME		"System Bus"
29 
30 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
31 
32 #define INVALID_ACPI_HANDLE	((acpi_handle)empty_zero_page)
33 
34 static const char *dummy_hid = "device";
35 
36 static LIST_HEAD(acpi_dep_list);
37 static DEFINE_MUTEX(acpi_dep_list_lock);
38 LIST_HEAD(acpi_bus_id_list);
39 static DEFINE_MUTEX(acpi_scan_lock);
40 static LIST_HEAD(acpi_scan_handlers_list);
41 DEFINE_MUTEX(acpi_device_lock);
42 LIST_HEAD(acpi_wakeup_device_list);
43 static DEFINE_MUTEX(acpi_hp_context_lock);
44 
45 /*
46  * The UART device described by the SPCR table is the only object which needs
47  * special-casing. Everything else is covered by ACPI namespace paths in STAO
48  * table.
49  */
50 static u64 spcr_uart_addr;
51 
52 struct acpi_dep_data {
53 	struct list_head node;
54 	acpi_handle supplier;
55 	acpi_handle consumer;
56 };
57 
58 void acpi_scan_lock_acquire(void)
59 {
60 	mutex_lock(&acpi_scan_lock);
61 }
62 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
63 
64 void acpi_scan_lock_release(void)
65 {
66 	mutex_unlock(&acpi_scan_lock);
67 }
68 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
69 
70 void acpi_lock_hp_context(void)
71 {
72 	mutex_lock(&acpi_hp_context_lock);
73 }
74 
75 void acpi_unlock_hp_context(void)
76 {
77 	mutex_unlock(&acpi_hp_context_lock);
78 }
79 
80 void acpi_initialize_hp_context(struct acpi_device *adev,
81 				struct acpi_hotplug_context *hp,
82 				int (*notify)(struct acpi_device *, u32),
83 				void (*uevent)(struct acpi_device *, u32))
84 {
85 	acpi_lock_hp_context();
86 	hp->notify = notify;
87 	hp->uevent = uevent;
88 	acpi_set_hp_context(adev, hp);
89 	acpi_unlock_hp_context();
90 }
91 EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
92 
93 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
94 {
95 	if (!handler)
96 		return -EINVAL;
97 
98 	list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
99 	return 0;
100 }
101 
102 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
103 				       const char *hotplug_profile_name)
104 {
105 	int error;
106 
107 	error = acpi_scan_add_handler(handler);
108 	if (error)
109 		return error;
110 
111 	acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
112 	return 0;
113 }
114 
115 bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
116 {
117 	struct acpi_device_physical_node *pn;
118 	bool offline = true;
119 	char *envp[] = { "EVENT=offline", NULL };
120 
121 	/*
122 	 * acpi_container_offline() calls this for all of the container's
123 	 * children under the container's physical_node_lock lock.
124 	 */
125 	mutex_lock_nested(&adev->physical_node_lock, SINGLE_DEPTH_NESTING);
126 
127 	list_for_each_entry(pn, &adev->physical_node_list, node)
128 		if (device_supports_offline(pn->dev) && !pn->dev->offline) {
129 			if (uevent)
130 				kobject_uevent_env(&pn->dev->kobj, KOBJ_CHANGE, envp);
131 
132 			offline = false;
133 			break;
134 		}
135 
136 	mutex_unlock(&adev->physical_node_lock);
137 	return offline;
138 }
139 
140 static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
141 				    void **ret_p)
142 {
143 	struct acpi_device *device = NULL;
144 	struct acpi_device_physical_node *pn;
145 	bool second_pass = (bool)data;
146 	acpi_status status = AE_OK;
147 
148 	if (acpi_bus_get_device(handle, &device))
149 		return AE_OK;
150 
151 	if (device->handler && !device->handler->hotplug.enabled) {
152 		*ret_p = &device->dev;
153 		return AE_SUPPORT;
154 	}
155 
156 	mutex_lock(&device->physical_node_lock);
157 
158 	list_for_each_entry(pn, &device->physical_node_list, node) {
159 		int ret;
160 
161 		if (second_pass) {
162 			/* Skip devices offlined by the first pass. */
163 			if (pn->put_online)
164 				continue;
165 		} else {
166 			pn->put_online = false;
167 		}
168 		ret = device_offline(pn->dev);
169 		if (ret >= 0) {
170 			pn->put_online = !ret;
171 		} else {
172 			*ret_p = pn->dev;
173 			if (second_pass) {
174 				status = AE_ERROR;
175 				break;
176 			}
177 		}
178 	}
179 
180 	mutex_unlock(&device->physical_node_lock);
181 
182 	return status;
183 }
184 
185 static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
186 				   void **ret_p)
187 {
188 	struct acpi_device *device = NULL;
189 	struct acpi_device_physical_node *pn;
190 
191 	if (acpi_bus_get_device(handle, &device))
192 		return AE_OK;
193 
194 	mutex_lock(&device->physical_node_lock);
195 
196 	list_for_each_entry(pn, &device->physical_node_list, node)
197 		if (pn->put_online) {
198 			device_online(pn->dev);
199 			pn->put_online = false;
200 		}
201 
202 	mutex_unlock(&device->physical_node_lock);
203 
204 	return AE_OK;
205 }
206 
207 static int acpi_scan_try_to_offline(struct acpi_device *device)
208 {
209 	acpi_handle handle = device->handle;
210 	struct device *errdev = NULL;
211 	acpi_status status;
212 
213 	/*
214 	 * Carry out two passes here and ignore errors in the first pass,
215 	 * because if the devices in question are memory blocks and
216 	 * CONFIG_MEMCG is set, one of the blocks may hold data structures
217 	 * that the other blocks depend on, but it is not known in advance which
218 	 * block holds them.
219 	 *
220 	 * If the first pass is successful, the second one isn't needed, though.
221 	 */
222 	status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
223 				     NULL, acpi_bus_offline, (void *)false,
224 				     (void **)&errdev);
225 	if (status == AE_SUPPORT) {
226 		dev_warn(errdev, "Offline disabled.\n");
227 		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
228 				    acpi_bus_online, NULL, NULL, NULL);
229 		return -EPERM;
230 	}
231 	acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
232 	if (errdev) {
233 		errdev = NULL;
234 		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
235 				    NULL, acpi_bus_offline, (void *)true,
236 				    (void **)&errdev);
237 		if (!errdev)
238 			acpi_bus_offline(handle, 0, (void *)true,
239 					 (void **)&errdev);
240 
241 		if (errdev) {
242 			dev_warn(errdev, "Offline failed.\n");
243 			acpi_bus_online(handle, 0, NULL, NULL);
244 			acpi_walk_namespace(ACPI_TYPE_ANY, handle,
245 					    ACPI_UINT32_MAX, acpi_bus_online,
246 					    NULL, NULL, NULL);
247 			return -EBUSY;
248 		}
249 	}
250 	return 0;
251 }
252 
253 static int acpi_scan_hot_remove(struct acpi_device *device)
254 {
255 	acpi_handle handle = device->handle;
256 	unsigned long long sta;
257 	acpi_status status;
258 
259 	if (device->handler && device->handler->hotplug.demand_offline) {
260 		if (!acpi_scan_is_offline(device, true))
261 			return -EBUSY;
262 	} else {
263 		int error = acpi_scan_try_to_offline(device);
264 		if (error)
265 			return error;
266 	}
267 
268 	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
269 		"Hot-removing device %s...\n", dev_name(&device->dev)));
270 
271 	acpi_bus_trim(device);
272 
273 	acpi_evaluate_lck(handle, 0);
274 	/*
275 	 * TBD: _EJD support.
276 	 */
277 	status = acpi_evaluate_ej0(handle);
278 	if (status == AE_NOT_FOUND)
279 		return -ENODEV;
280 	else if (ACPI_FAILURE(status))
281 		return -EIO;
282 
283 	/*
284 	 * Verify if eject was indeed successful.  If not, log an error
285 	 * message.  No need to call _OST since _EJ0 call was made OK.
286 	 */
287 	status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
288 	if (ACPI_FAILURE(status)) {
289 		acpi_handle_warn(handle,
290 			"Status check after eject failed (0x%x)\n", status);
291 	} else if (sta & ACPI_STA_DEVICE_ENABLED) {
292 		acpi_handle_warn(handle,
293 			"Eject incomplete - status 0x%llx\n", sta);
294 	}
295 
296 	return 0;
297 }
298 
299 static int acpi_scan_device_not_present(struct acpi_device *adev)
300 {
301 	if (!acpi_device_enumerated(adev)) {
302 		dev_warn(&adev->dev, "Still not present\n");
303 		return -EALREADY;
304 	}
305 	acpi_bus_trim(adev);
306 	return 0;
307 }
308 
309 static int acpi_scan_device_check(struct acpi_device *adev)
310 {
311 	int error;
312 
313 	acpi_bus_get_status(adev);
314 	if (adev->status.present || adev->status.functional) {
315 		/*
316 		 * This function is only called for device objects for which
317 		 * matching scan handlers exist.  The only situation in which
318 		 * the scan handler is not attached to this device object yet
319 		 * is when the device has just appeared (either it wasn't
320 		 * present at all before or it was removed and then added
321 		 * again).
322 		 */
323 		if (adev->handler) {
324 			dev_warn(&adev->dev, "Already enumerated\n");
325 			return -EALREADY;
326 		}
327 		error = acpi_bus_scan(adev->handle);
328 		if (error) {
329 			dev_warn(&adev->dev, "Namespace scan failure\n");
330 			return error;
331 		}
332 		if (!adev->handler) {
333 			dev_warn(&adev->dev, "Enumeration failure\n");
334 			error = -ENODEV;
335 		}
336 	} else {
337 		error = acpi_scan_device_not_present(adev);
338 	}
339 	return error;
340 }
341 
342 static int acpi_scan_bus_check(struct acpi_device *adev)
343 {
344 	struct acpi_scan_handler *handler = adev->handler;
345 	struct acpi_device *child;
346 	int error;
347 
348 	acpi_bus_get_status(adev);
349 	if (!(adev->status.present || adev->status.functional)) {
350 		acpi_scan_device_not_present(adev);
351 		return 0;
352 	}
353 	if (handler && handler->hotplug.scan_dependent)
354 		return handler->hotplug.scan_dependent(adev);
355 
356 	error = acpi_bus_scan(adev->handle);
357 	if (error) {
358 		dev_warn(&adev->dev, "Namespace scan failure\n");
359 		return error;
360 	}
361 	list_for_each_entry(child, &adev->children, node) {
362 		error = acpi_scan_bus_check(child);
363 		if (error)
364 			return error;
365 	}
366 	return 0;
367 }
368 
369 static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type)
370 {
371 	switch (type) {
372 	case ACPI_NOTIFY_BUS_CHECK:
373 		return acpi_scan_bus_check(adev);
374 	case ACPI_NOTIFY_DEVICE_CHECK:
375 		return acpi_scan_device_check(adev);
376 	case ACPI_NOTIFY_EJECT_REQUEST:
377 	case ACPI_OST_EC_OSPM_EJECT:
378 		if (adev->handler && !adev->handler->hotplug.enabled) {
379 			dev_info(&adev->dev, "Eject disabled\n");
380 			return -EPERM;
381 		}
382 		acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST,
383 				  ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
384 		return acpi_scan_hot_remove(adev);
385 	}
386 	return -EINVAL;
387 }
388 
389 void acpi_device_hotplug(struct acpi_device *adev, u32 src)
390 {
391 	u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
392 	int error = -ENODEV;
393 
394 	lock_device_hotplug();
395 	mutex_lock(&acpi_scan_lock);
396 
397 	/*
398 	 * The device object's ACPI handle cannot become invalid as long as we
399 	 * are holding acpi_scan_lock, but it might have become invalid before
400 	 * that lock was acquired.
401 	 */
402 	if (adev->handle == INVALID_ACPI_HANDLE)
403 		goto err_out;
404 
405 	if (adev->flags.is_dock_station) {
406 		error = dock_notify(adev, src);
407 	} else if (adev->flags.hotplug_notify) {
408 		error = acpi_generic_hotplug_event(adev, src);
409 	} else {
410 		int (*notify)(struct acpi_device *, u32);
411 
412 		acpi_lock_hp_context();
413 		notify = adev->hp ? adev->hp->notify : NULL;
414 		acpi_unlock_hp_context();
415 		/*
416 		 * There may be additional notify handlers for device objects
417 		 * without the .event() callback, so ignore them here.
418 		 */
419 		if (notify)
420 			error = notify(adev, src);
421 		else
422 			goto out;
423 	}
424 	switch (error) {
425 	case 0:
426 		ost_code = ACPI_OST_SC_SUCCESS;
427 		break;
428 	case -EPERM:
429 		ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
430 		break;
431 	case -EBUSY:
432 		ost_code = ACPI_OST_SC_DEVICE_BUSY;
433 		break;
434 	default:
435 		ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
436 		break;
437 	}
438 
439  err_out:
440 	acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
441 
442  out:
443 	acpi_bus_put_acpi_device(adev);
444 	mutex_unlock(&acpi_scan_lock);
445 	unlock_device_hotplug();
446 }
447 
448 static void acpi_free_power_resources_lists(struct acpi_device *device)
449 {
450 	int i;
451 
452 	if (device->wakeup.flags.valid)
453 		acpi_power_resources_list_free(&device->wakeup.resources);
454 
455 	if (!device->power.flags.power_resources)
456 		return;
457 
458 	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
459 		struct acpi_device_power_state *ps = &device->power.states[i];
460 		acpi_power_resources_list_free(&ps->resources);
461 	}
462 }
463 
464 static void acpi_device_release(struct device *dev)
465 {
466 	struct acpi_device *acpi_dev = to_acpi_device(dev);
467 
468 	acpi_free_properties(acpi_dev);
469 	acpi_free_pnp_ids(&acpi_dev->pnp);
470 	acpi_free_power_resources_lists(acpi_dev);
471 	kfree(acpi_dev);
472 }
473 
474 static void acpi_device_del(struct acpi_device *device)
475 {
476 	struct acpi_device_bus_id *acpi_device_bus_id;
477 
478 	mutex_lock(&acpi_device_lock);
479 	if (device->parent)
480 		list_del(&device->node);
481 
482 	list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node)
483 		if (!strcmp(acpi_device_bus_id->bus_id,
484 			    acpi_device_hid(device))) {
485 			if (acpi_device_bus_id->instance_no > 0)
486 				acpi_device_bus_id->instance_no--;
487 			else {
488 				list_del(&acpi_device_bus_id->node);
489 				kfree(acpi_device_bus_id);
490 			}
491 			break;
492 		}
493 
494 	list_del(&device->wakeup_list);
495 	mutex_unlock(&acpi_device_lock);
496 
497 	acpi_power_add_remove_device(device, false);
498 	acpi_device_remove_files(device);
499 	if (device->remove)
500 		device->remove(device);
501 
502 	device_del(&device->dev);
503 }
504 
505 static BLOCKING_NOTIFIER_HEAD(acpi_reconfig_chain);
506 
507 static LIST_HEAD(acpi_device_del_list);
508 static DEFINE_MUTEX(acpi_device_del_lock);
509 
510 static void acpi_device_del_work_fn(struct work_struct *work_not_used)
511 {
512 	for (;;) {
513 		struct acpi_device *adev;
514 
515 		mutex_lock(&acpi_device_del_lock);
516 
517 		if (list_empty(&acpi_device_del_list)) {
518 			mutex_unlock(&acpi_device_del_lock);
519 			break;
520 		}
521 		adev = list_first_entry(&acpi_device_del_list,
522 					struct acpi_device, del_list);
523 		list_del(&adev->del_list);
524 
525 		mutex_unlock(&acpi_device_del_lock);
526 
527 		blocking_notifier_call_chain(&acpi_reconfig_chain,
528 					     ACPI_RECONFIG_DEVICE_REMOVE, adev);
529 
530 		acpi_device_del(adev);
531 		/*
532 		 * Drop references to all power resources that might have been
533 		 * used by the device.
534 		 */
535 		acpi_power_transition(adev, ACPI_STATE_D3_COLD);
536 		put_device(&adev->dev);
537 	}
538 }
539 
540 /**
541  * acpi_scan_drop_device - Drop an ACPI device object.
542  * @handle: Handle of an ACPI namespace node, not used.
543  * @context: Address of the ACPI device object to drop.
544  *
545  * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
546  * namespace node the device object pointed to by @context is attached to.
547  *
548  * The unregistration is carried out asynchronously to avoid running
549  * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
550  * ensure the correct ordering (the device objects must be unregistered in the
551  * same order in which the corresponding namespace nodes are deleted).
552  */
553 static void acpi_scan_drop_device(acpi_handle handle, void *context)
554 {
555 	static DECLARE_WORK(work, acpi_device_del_work_fn);
556 	struct acpi_device *adev = context;
557 
558 	mutex_lock(&acpi_device_del_lock);
559 
560 	/*
561 	 * Use the ACPI hotplug workqueue which is ordered, so this work item
562 	 * won't run after any hotplug work items submitted subsequently.  That
563 	 * prevents attempts to register device objects identical to those being
564 	 * deleted from happening concurrently (such attempts result from
565 	 * hotplug events handled via the ACPI hotplug workqueue).  It also will
566 	 * run after all of the work items submitted previosuly, which helps
567 	 * those work items to ensure that they are not accessing stale device
568 	 * objects.
569 	 */
570 	if (list_empty(&acpi_device_del_list))
571 		acpi_queue_hotplug_work(&work);
572 
573 	list_add_tail(&adev->del_list, &acpi_device_del_list);
574 	/* Make acpi_ns_validate_handle() return NULL for this handle. */
575 	adev->handle = INVALID_ACPI_HANDLE;
576 
577 	mutex_unlock(&acpi_device_del_lock);
578 }
579 
580 static int acpi_get_device_data(acpi_handle handle, struct acpi_device **device,
581 				void (*callback)(void *))
582 {
583 	acpi_status status;
584 
585 	if (!device)
586 		return -EINVAL;
587 
588 	status = acpi_get_data_full(handle, acpi_scan_drop_device,
589 				    (void **)device, callback);
590 	if (ACPI_FAILURE(status) || !*device) {
591 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
592 				  handle));
593 		return -ENODEV;
594 	}
595 	return 0;
596 }
597 
598 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
599 {
600 	return acpi_get_device_data(handle, device, NULL);
601 }
602 EXPORT_SYMBOL(acpi_bus_get_device);
603 
604 static void get_acpi_device(void *dev)
605 {
606 	if (dev)
607 		get_device(&((struct acpi_device *)dev)->dev);
608 }
609 
610 struct acpi_device *acpi_bus_get_acpi_device(acpi_handle handle)
611 {
612 	struct acpi_device *adev = NULL;
613 
614 	acpi_get_device_data(handle, &adev, get_acpi_device);
615 	return adev;
616 }
617 
618 void acpi_bus_put_acpi_device(struct acpi_device *adev)
619 {
620 	put_device(&adev->dev);
621 }
622 
623 int acpi_device_add(struct acpi_device *device,
624 		    void (*release)(struct device *))
625 {
626 	int result;
627 	struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
628 	int found = 0;
629 
630 	if (device->handle) {
631 		acpi_status status;
632 
633 		status = acpi_attach_data(device->handle, acpi_scan_drop_device,
634 					  device);
635 		if (ACPI_FAILURE(status)) {
636 			acpi_handle_err(device->handle,
637 					"Unable to attach device data\n");
638 			return -ENODEV;
639 		}
640 	}
641 
642 	/*
643 	 * Linkage
644 	 * -------
645 	 * Link this device to its parent and siblings.
646 	 */
647 	INIT_LIST_HEAD(&device->children);
648 	INIT_LIST_HEAD(&device->node);
649 	INIT_LIST_HEAD(&device->wakeup_list);
650 	INIT_LIST_HEAD(&device->physical_node_list);
651 	INIT_LIST_HEAD(&device->del_list);
652 	mutex_init(&device->physical_node_lock);
653 
654 	new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
655 	if (!new_bus_id) {
656 		pr_err(PREFIX "Memory allocation error\n");
657 		result = -ENOMEM;
658 		goto err_detach;
659 	}
660 
661 	mutex_lock(&acpi_device_lock);
662 	/*
663 	 * Find suitable bus_id and instance number in acpi_bus_id_list
664 	 * If failed, create one and link it into acpi_bus_id_list
665 	 */
666 	list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
667 		if (!strcmp(acpi_device_bus_id->bus_id,
668 			    acpi_device_hid(device))) {
669 			acpi_device_bus_id->instance_no++;
670 			found = 1;
671 			kfree(new_bus_id);
672 			break;
673 		}
674 	}
675 	if (!found) {
676 		acpi_device_bus_id = new_bus_id;
677 		strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
678 		acpi_device_bus_id->instance_no = 0;
679 		list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
680 	}
681 	dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
682 
683 	if (device->parent)
684 		list_add_tail(&device->node, &device->parent->children);
685 
686 	if (device->wakeup.flags.valid)
687 		list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
688 	mutex_unlock(&acpi_device_lock);
689 
690 	if (device->parent)
691 		device->dev.parent = &device->parent->dev;
692 	device->dev.bus = &acpi_bus_type;
693 	device->dev.release = release;
694 	result = device_add(&device->dev);
695 	if (result) {
696 		dev_err(&device->dev, "Error registering device\n");
697 		goto err;
698 	}
699 
700 	result = acpi_device_setup_files(device);
701 	if (result)
702 		printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
703 		       dev_name(&device->dev));
704 
705 	return 0;
706 
707  err:
708 	mutex_lock(&acpi_device_lock);
709 	if (device->parent)
710 		list_del(&device->node);
711 	list_del(&device->wakeup_list);
712 	mutex_unlock(&acpi_device_lock);
713 
714  err_detach:
715 	acpi_detach_data(device->handle, acpi_scan_drop_device);
716 	return result;
717 }
718 
719 /* --------------------------------------------------------------------------
720                                  Device Enumeration
721    -------------------------------------------------------------------------- */
722 static bool acpi_info_matches_ids(struct acpi_device_info *info,
723 				  const char * const ids[])
724 {
725 	struct acpi_pnp_device_id_list *cid_list = NULL;
726 	int i;
727 
728 	if (!(info->valid & ACPI_VALID_HID))
729 		return false;
730 
731 	if (info->valid & ACPI_VALID_CID)
732 		cid_list = &info->compatible_id_list;
733 
734 	for (i = 0; ids[i]; i++) {
735 		int j;
736 
737 		if (!strcmp(info->hardware_id.string, ids[i]))
738 			return true;
739 
740 		if (!cid_list)
741 			continue;
742 
743 		for (j = 0; j < cid_list->count; j++) {
744 			if (!strcmp(cid_list->ids[j].string, ids[i]))
745 				return true;
746 		}
747 	}
748 
749 	return false;
750 }
751 
752 /* List of HIDs for which we ignore matching ACPI devices, when checking _DEP lists. */
753 static const char * const acpi_ignore_dep_ids[] = {
754 	"PNP0D80", /* Windows-compatible System Power Management Controller */
755 	NULL
756 };
757 
758 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
759 {
760 	struct acpi_device *device = NULL;
761 	acpi_status status;
762 
763 	/*
764 	 * Fixed hardware devices do not appear in the namespace and do not
765 	 * have handles, but we fabricate acpi_devices for them, so we have
766 	 * to deal with them specially.
767 	 */
768 	if (!handle)
769 		return acpi_root;
770 
771 	do {
772 		status = acpi_get_parent(handle, &handle);
773 		if (ACPI_FAILURE(status))
774 			return status == AE_NULL_ENTRY ? NULL : acpi_root;
775 	} while (acpi_bus_get_device(handle, &device));
776 	return device;
777 }
778 
779 acpi_status
780 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
781 {
782 	acpi_status status;
783 	acpi_handle tmp;
784 	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
785 	union acpi_object *obj;
786 
787 	status = acpi_get_handle(handle, "_EJD", &tmp);
788 	if (ACPI_FAILURE(status))
789 		return status;
790 
791 	status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
792 	if (ACPI_SUCCESS(status)) {
793 		obj = buffer.pointer;
794 		status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
795 					 ejd);
796 		kfree(buffer.pointer);
797 	}
798 	return status;
799 }
800 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
801 
802 static int acpi_bus_extract_wakeup_device_power_package(struct acpi_device *dev)
803 {
804 	acpi_handle handle = dev->handle;
805 	struct acpi_device_wakeup *wakeup = &dev->wakeup;
806 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
807 	union acpi_object *package = NULL;
808 	union acpi_object *element = NULL;
809 	acpi_status status;
810 	int err = -ENODATA;
811 
812 	INIT_LIST_HEAD(&wakeup->resources);
813 
814 	/* _PRW */
815 	status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
816 	if (ACPI_FAILURE(status)) {
817 		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
818 		return err;
819 	}
820 
821 	package = (union acpi_object *)buffer.pointer;
822 
823 	if (!package || package->package.count < 2)
824 		goto out;
825 
826 	element = &(package->package.elements[0]);
827 	if (!element)
828 		goto out;
829 
830 	if (element->type == ACPI_TYPE_PACKAGE) {
831 		if ((element->package.count < 2) ||
832 		    (element->package.elements[0].type !=
833 		     ACPI_TYPE_LOCAL_REFERENCE)
834 		    || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
835 			goto out;
836 
837 		wakeup->gpe_device =
838 		    element->package.elements[0].reference.handle;
839 		wakeup->gpe_number =
840 		    (u32) element->package.elements[1].integer.value;
841 	} else if (element->type == ACPI_TYPE_INTEGER) {
842 		wakeup->gpe_device = NULL;
843 		wakeup->gpe_number = element->integer.value;
844 	} else {
845 		goto out;
846 	}
847 
848 	element = &(package->package.elements[1]);
849 	if (element->type != ACPI_TYPE_INTEGER)
850 		goto out;
851 
852 	wakeup->sleep_state = element->integer.value;
853 
854 	err = acpi_extract_power_resources(package, 2, &wakeup->resources);
855 	if (err)
856 		goto out;
857 
858 	if (!list_empty(&wakeup->resources)) {
859 		int sleep_state;
860 
861 		err = acpi_power_wakeup_list_init(&wakeup->resources,
862 						  &sleep_state);
863 		if (err) {
864 			acpi_handle_warn(handle, "Retrieving current states "
865 					 "of wakeup power resources failed\n");
866 			acpi_power_resources_list_free(&wakeup->resources);
867 			goto out;
868 		}
869 		if (sleep_state < wakeup->sleep_state) {
870 			acpi_handle_warn(handle, "Overriding _PRW sleep state "
871 					 "(S%d) by S%d from power resources\n",
872 					 (int)wakeup->sleep_state, sleep_state);
873 			wakeup->sleep_state = sleep_state;
874 		}
875 	}
876 
877  out:
878 	kfree(buffer.pointer);
879 	return err;
880 }
881 
882 static bool acpi_wakeup_gpe_init(struct acpi_device *device)
883 {
884 	static const struct acpi_device_id button_device_ids[] = {
885 		{"PNP0C0C", 0},		/* Power button */
886 		{"PNP0C0D", 0},		/* Lid */
887 		{"PNP0C0E", 0},		/* Sleep button */
888 		{"", 0},
889 	};
890 	struct acpi_device_wakeup *wakeup = &device->wakeup;
891 	acpi_status status;
892 
893 	wakeup->flags.notifier_present = 0;
894 
895 	/* Power button, Lid switch always enable wakeup */
896 	if (!acpi_match_device_ids(device, button_device_ids)) {
897 		if (!acpi_match_device_ids(device, &button_device_ids[1])) {
898 			/* Do not use Lid/sleep button for S5 wakeup */
899 			if (wakeup->sleep_state == ACPI_STATE_S5)
900 				wakeup->sleep_state = ACPI_STATE_S4;
901 		}
902 		acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
903 		device_set_wakeup_capable(&device->dev, true);
904 		return true;
905 	}
906 
907 	status = acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
908 					 wakeup->gpe_number);
909 	return ACPI_SUCCESS(status);
910 }
911 
912 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
913 {
914 	int err;
915 
916 	/* Presence of _PRW indicates wake capable */
917 	if (!acpi_has_method(device->handle, "_PRW"))
918 		return;
919 
920 	err = acpi_bus_extract_wakeup_device_power_package(device);
921 	if (err) {
922 		dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
923 		return;
924 	}
925 
926 	device->wakeup.flags.valid = acpi_wakeup_gpe_init(device);
927 	device->wakeup.prepare_count = 0;
928 	/*
929 	 * Call _PSW/_DSW object to disable its ability to wake the sleeping
930 	 * system for the ACPI device with the _PRW object.
931 	 * The _PSW object is deprecated in ACPI 3.0 and is replaced by _DSW.
932 	 * So it is necessary to call _DSW object first. Only when it is not
933 	 * present will the _PSW object used.
934 	 */
935 	err = acpi_device_sleep_wake(device, 0, 0, 0);
936 	if (err)
937 		pr_debug("error in _DSW or _PSW evaluation\n");
938 }
939 
940 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
941 {
942 	struct acpi_device_power_state *ps = &device->power.states[state];
943 	char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
944 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
945 	acpi_status status;
946 
947 	INIT_LIST_HEAD(&ps->resources);
948 
949 	/* Evaluate "_PRx" to get referenced power resources */
950 	status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
951 	if (ACPI_SUCCESS(status)) {
952 		union acpi_object *package = buffer.pointer;
953 
954 		if (buffer.length && package
955 		    && package->type == ACPI_TYPE_PACKAGE
956 		    && package->package.count)
957 			acpi_extract_power_resources(package, 0, &ps->resources);
958 
959 		ACPI_FREE(buffer.pointer);
960 	}
961 
962 	/* Evaluate "_PSx" to see if we can do explicit sets */
963 	pathname[2] = 'S';
964 	if (acpi_has_method(device->handle, pathname))
965 		ps->flags.explicit_set = 1;
966 
967 	/* State is valid if there are means to put the device into it. */
968 	if (!list_empty(&ps->resources) || ps->flags.explicit_set)
969 		ps->flags.valid = 1;
970 
971 	ps->power = -1;		/* Unknown - driver assigned */
972 	ps->latency = -1;	/* Unknown - driver assigned */
973 }
974 
975 static void acpi_bus_get_power_flags(struct acpi_device *device)
976 {
977 	u32 i;
978 
979 	/* Presence of _PS0|_PR0 indicates 'power manageable' */
980 	if (!acpi_has_method(device->handle, "_PS0") &&
981 	    !acpi_has_method(device->handle, "_PR0"))
982 		return;
983 
984 	device->flags.power_manageable = 1;
985 
986 	/*
987 	 * Power Management Flags
988 	 */
989 	if (acpi_has_method(device->handle, "_PSC"))
990 		device->power.flags.explicit_get = 1;
991 
992 	if (acpi_has_method(device->handle, "_IRC"))
993 		device->power.flags.inrush_current = 1;
994 
995 	if (acpi_has_method(device->handle, "_DSW"))
996 		device->power.flags.dsw_present = 1;
997 
998 	/*
999 	 * Enumerate supported power management states
1000 	 */
1001 	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
1002 		acpi_bus_init_power_state(device, i);
1003 
1004 	INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
1005 
1006 	/* Set the defaults for D0 and D3hot (always supported). */
1007 	device->power.states[ACPI_STATE_D0].flags.valid = 1;
1008 	device->power.states[ACPI_STATE_D0].power = 100;
1009 	device->power.states[ACPI_STATE_D3_HOT].flags.valid = 1;
1010 
1011 	/*
1012 	 * Use power resources only if the D0 list of them is populated, because
1013 	 * some platforms may provide _PR3 only to indicate D3cold support and
1014 	 * in those cases the power resources list returned by it may be bogus.
1015 	 */
1016 	if (!list_empty(&device->power.states[ACPI_STATE_D0].resources)) {
1017 		device->power.flags.power_resources = 1;
1018 		/*
1019 		 * D3cold is supported if the D3hot list of power resources is
1020 		 * not empty.
1021 		 */
1022 		if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources))
1023 			device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
1024 	}
1025 
1026 	if (acpi_bus_init_power(device))
1027 		device->flags.power_manageable = 0;
1028 }
1029 
1030 static void acpi_bus_get_flags(struct acpi_device *device)
1031 {
1032 	/* Presence of _STA indicates 'dynamic_status' */
1033 	if (acpi_has_method(device->handle, "_STA"))
1034 		device->flags.dynamic_status = 1;
1035 
1036 	/* Presence of _RMV indicates 'removable' */
1037 	if (acpi_has_method(device->handle, "_RMV"))
1038 		device->flags.removable = 1;
1039 
1040 	/* Presence of _EJD|_EJ0 indicates 'ejectable' */
1041 	if (acpi_has_method(device->handle, "_EJD") ||
1042 	    acpi_has_method(device->handle, "_EJ0"))
1043 		device->flags.ejectable = 1;
1044 }
1045 
1046 static void acpi_device_get_busid(struct acpi_device *device)
1047 {
1048 	char bus_id[5] = { '?', 0 };
1049 	struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1050 	int i = 0;
1051 
1052 	/*
1053 	 * Bus ID
1054 	 * ------
1055 	 * The device's Bus ID is simply the object name.
1056 	 * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1057 	 */
1058 	if (ACPI_IS_ROOT_DEVICE(device)) {
1059 		strcpy(device->pnp.bus_id, "ACPI");
1060 		return;
1061 	}
1062 
1063 	switch (device->device_type) {
1064 	case ACPI_BUS_TYPE_POWER_BUTTON:
1065 		strcpy(device->pnp.bus_id, "PWRF");
1066 		break;
1067 	case ACPI_BUS_TYPE_SLEEP_BUTTON:
1068 		strcpy(device->pnp.bus_id, "SLPF");
1069 		break;
1070 	case ACPI_BUS_TYPE_ECDT_EC:
1071 		strcpy(device->pnp.bus_id, "ECDT");
1072 		break;
1073 	default:
1074 		acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1075 		/* Clean up trailing underscores (if any) */
1076 		for (i = 3; i > 1; i--) {
1077 			if (bus_id[i] == '_')
1078 				bus_id[i] = '\0';
1079 			else
1080 				break;
1081 		}
1082 		strcpy(device->pnp.bus_id, bus_id);
1083 		break;
1084 	}
1085 }
1086 
1087 /*
1088  * acpi_ata_match - see if an acpi object is an ATA device
1089  *
1090  * If an acpi object has one of the ACPI ATA methods defined,
1091  * then we can safely call it an ATA device.
1092  */
1093 bool acpi_ata_match(acpi_handle handle)
1094 {
1095 	return acpi_has_method(handle, "_GTF") ||
1096 	       acpi_has_method(handle, "_GTM") ||
1097 	       acpi_has_method(handle, "_STM") ||
1098 	       acpi_has_method(handle, "_SDD");
1099 }
1100 
1101 /*
1102  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1103  *
1104  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1105  * then we can safely call it an ejectable drive bay
1106  */
1107 bool acpi_bay_match(acpi_handle handle)
1108 {
1109 	acpi_handle phandle;
1110 
1111 	if (!acpi_has_method(handle, "_EJ0"))
1112 		return false;
1113 	if (acpi_ata_match(handle))
1114 		return true;
1115 	if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1116 		return false;
1117 
1118 	return acpi_ata_match(phandle);
1119 }
1120 
1121 bool acpi_device_is_battery(struct acpi_device *adev)
1122 {
1123 	struct acpi_hardware_id *hwid;
1124 
1125 	list_for_each_entry(hwid, &adev->pnp.ids, list)
1126 		if (!strcmp("PNP0C0A", hwid->id))
1127 			return true;
1128 
1129 	return false;
1130 }
1131 
1132 static bool is_ejectable_bay(struct acpi_device *adev)
1133 {
1134 	acpi_handle handle = adev->handle;
1135 
1136 	if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
1137 		return true;
1138 
1139 	return acpi_bay_match(handle);
1140 }
1141 
1142 /*
1143  * acpi_dock_match - see if an acpi object has a _DCK method
1144  */
1145 bool acpi_dock_match(acpi_handle handle)
1146 {
1147 	return acpi_has_method(handle, "_DCK");
1148 }
1149 
1150 static acpi_status
1151 acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
1152 			  void **return_value)
1153 {
1154 	long *cap = context;
1155 
1156 	if (acpi_has_method(handle, "_BCM") &&
1157 	    acpi_has_method(handle, "_BCL")) {
1158 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight "
1159 				  "support\n"));
1160 		*cap |= ACPI_VIDEO_BACKLIGHT;
1161 		/* We have backlight support, no need to scan further */
1162 		return AE_CTRL_TERMINATE;
1163 	}
1164 	return 0;
1165 }
1166 
1167 /* Returns true if the ACPI object is a video device which can be
1168  * handled by video.ko.
1169  * The device will get a Linux specific CID added in scan.c to
1170  * identify the device as an ACPI graphics device
1171  * Be aware that the graphics device may not be physically present
1172  * Use acpi_video_get_capabilities() to detect general ACPI video
1173  * capabilities of present cards
1174  */
1175 long acpi_is_video_device(acpi_handle handle)
1176 {
1177 	long video_caps = 0;
1178 
1179 	/* Is this device able to support video switching ? */
1180 	if (acpi_has_method(handle, "_DOD") || acpi_has_method(handle, "_DOS"))
1181 		video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
1182 
1183 	/* Is this device able to retrieve a video ROM ? */
1184 	if (acpi_has_method(handle, "_ROM"))
1185 		video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
1186 
1187 	/* Is this device able to configure which video head to be POSTed ? */
1188 	if (acpi_has_method(handle, "_VPO") &&
1189 	    acpi_has_method(handle, "_GPD") &&
1190 	    acpi_has_method(handle, "_SPD"))
1191 		video_caps |= ACPI_VIDEO_DEVICE_POSTING;
1192 
1193 	/* Only check for backlight functionality if one of the above hit. */
1194 	if (video_caps)
1195 		acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
1196 				    ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
1197 				    &video_caps, NULL);
1198 
1199 	return video_caps;
1200 }
1201 EXPORT_SYMBOL(acpi_is_video_device);
1202 
1203 const char *acpi_device_hid(struct acpi_device *device)
1204 {
1205 	struct acpi_hardware_id *hid;
1206 
1207 	if (list_empty(&device->pnp.ids))
1208 		return dummy_hid;
1209 
1210 	hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1211 	return hid->id;
1212 }
1213 EXPORT_SYMBOL(acpi_device_hid);
1214 
1215 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1216 {
1217 	struct acpi_hardware_id *id;
1218 
1219 	id = kmalloc(sizeof(*id), GFP_KERNEL);
1220 	if (!id)
1221 		return;
1222 
1223 	id->id = kstrdup_const(dev_id, GFP_KERNEL);
1224 	if (!id->id) {
1225 		kfree(id);
1226 		return;
1227 	}
1228 
1229 	list_add_tail(&id->list, &pnp->ids);
1230 	pnp->type.hardware_id = 1;
1231 }
1232 
1233 /*
1234  * Old IBM workstations have a DSDT bug wherein the SMBus object
1235  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1236  * prefix.  Work around this.
1237  */
1238 static bool acpi_ibm_smbus_match(acpi_handle handle)
1239 {
1240 	char node_name[ACPI_PATH_SEGMENT_LENGTH];
1241 	struct acpi_buffer path = { sizeof(node_name), node_name };
1242 
1243 	if (!dmi_name_in_vendors("IBM"))
1244 		return false;
1245 
1246 	/* Look for SMBS object */
1247 	if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1248 	    strcmp("SMBS", path.pointer))
1249 		return false;
1250 
1251 	/* Does it have the necessary (but misnamed) methods? */
1252 	if (acpi_has_method(handle, "SBI") &&
1253 	    acpi_has_method(handle, "SBR") &&
1254 	    acpi_has_method(handle, "SBW"))
1255 		return true;
1256 
1257 	return false;
1258 }
1259 
1260 static bool acpi_object_is_system_bus(acpi_handle handle)
1261 {
1262 	acpi_handle tmp;
1263 
1264 	if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
1265 	    tmp == handle)
1266 		return true;
1267 	if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
1268 	    tmp == handle)
1269 		return true;
1270 
1271 	return false;
1272 }
1273 
1274 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1275 				int device_type, struct acpi_device_info *info)
1276 {
1277 	struct acpi_pnp_device_id_list *cid_list;
1278 	int i;
1279 
1280 	switch (device_type) {
1281 	case ACPI_BUS_TYPE_DEVICE:
1282 		if (handle == ACPI_ROOT_OBJECT) {
1283 			acpi_add_id(pnp, ACPI_SYSTEM_HID);
1284 			break;
1285 		}
1286 
1287 		if (!info) {
1288 			pr_err(PREFIX "%s: Error reading device info\n",
1289 					__func__);
1290 			return;
1291 		}
1292 
1293 		if (info->valid & ACPI_VALID_HID) {
1294 			acpi_add_id(pnp, info->hardware_id.string);
1295 			pnp->type.platform_id = 1;
1296 		}
1297 		if (info->valid & ACPI_VALID_CID) {
1298 			cid_list = &info->compatible_id_list;
1299 			for (i = 0; i < cid_list->count; i++)
1300 				acpi_add_id(pnp, cid_list->ids[i].string);
1301 		}
1302 		if (info->valid & ACPI_VALID_ADR) {
1303 			pnp->bus_address = info->address;
1304 			pnp->type.bus_address = 1;
1305 		}
1306 		if (info->valid & ACPI_VALID_UID)
1307 			pnp->unique_id = kstrdup(info->unique_id.string,
1308 							GFP_KERNEL);
1309 		if (info->valid & ACPI_VALID_CLS)
1310 			acpi_add_id(pnp, info->class_code.string);
1311 
1312 		/*
1313 		 * Some devices don't reliably have _HIDs & _CIDs, so add
1314 		 * synthetic HIDs to make sure drivers can find them.
1315 		 */
1316 		if (acpi_is_video_device(handle))
1317 			acpi_add_id(pnp, ACPI_VIDEO_HID);
1318 		else if (acpi_bay_match(handle))
1319 			acpi_add_id(pnp, ACPI_BAY_HID);
1320 		else if (acpi_dock_match(handle))
1321 			acpi_add_id(pnp, ACPI_DOCK_HID);
1322 		else if (acpi_ibm_smbus_match(handle))
1323 			acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1324 		else if (list_empty(&pnp->ids) &&
1325 			 acpi_object_is_system_bus(handle)) {
1326 			/* \_SB, \_TZ, LNXSYBUS */
1327 			acpi_add_id(pnp, ACPI_BUS_HID);
1328 			strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1329 			strcpy(pnp->device_class, ACPI_BUS_CLASS);
1330 		}
1331 
1332 		break;
1333 	case ACPI_BUS_TYPE_POWER:
1334 		acpi_add_id(pnp, ACPI_POWER_HID);
1335 		break;
1336 	case ACPI_BUS_TYPE_PROCESSOR:
1337 		acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1338 		break;
1339 	case ACPI_BUS_TYPE_THERMAL:
1340 		acpi_add_id(pnp, ACPI_THERMAL_HID);
1341 		break;
1342 	case ACPI_BUS_TYPE_POWER_BUTTON:
1343 		acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1344 		break;
1345 	case ACPI_BUS_TYPE_SLEEP_BUTTON:
1346 		acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1347 		break;
1348 	case ACPI_BUS_TYPE_ECDT_EC:
1349 		acpi_add_id(pnp, ACPI_ECDT_HID);
1350 		break;
1351 	}
1352 }
1353 
1354 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1355 {
1356 	struct acpi_hardware_id *id, *tmp;
1357 
1358 	list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1359 		kfree_const(id->id);
1360 		kfree(id);
1361 	}
1362 	kfree(pnp->unique_id);
1363 }
1364 
1365 /**
1366  * acpi_dma_supported - Check DMA support for the specified device.
1367  * @adev: The pointer to acpi device
1368  *
1369  * Return false if DMA is not supported. Otherwise, return true
1370  */
1371 bool acpi_dma_supported(struct acpi_device *adev)
1372 {
1373 	if (!adev)
1374 		return false;
1375 
1376 	if (adev->flags.cca_seen)
1377 		return true;
1378 
1379 	/*
1380 	* Per ACPI 6.0 sec 6.2.17, assume devices can do cache-coherent
1381 	* DMA on "Intel platforms".  Presumably that includes all x86 and
1382 	* ia64, and other arches will set CONFIG_ACPI_CCA_REQUIRED=y.
1383 	*/
1384 	if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1385 		return true;
1386 
1387 	return false;
1388 }
1389 
1390 /**
1391  * acpi_get_dma_attr - Check the supported DMA attr for the specified device.
1392  * @adev: The pointer to acpi device
1393  *
1394  * Return enum dev_dma_attr.
1395  */
1396 enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
1397 {
1398 	if (!acpi_dma_supported(adev))
1399 		return DEV_DMA_NOT_SUPPORTED;
1400 
1401 	if (adev->flags.coherent_dma)
1402 		return DEV_DMA_COHERENT;
1403 	else
1404 		return DEV_DMA_NON_COHERENT;
1405 }
1406 
1407 /**
1408  * acpi_dma_get_range() - Get device DMA parameters.
1409  *
1410  * @dev: device to configure
1411  * @dma_addr: pointer device DMA address result
1412  * @offset: pointer to the DMA offset result
1413  * @size: pointer to DMA range size result
1414  *
1415  * Evaluate DMA regions and return respectively DMA region start, offset
1416  * and size in dma_addr, offset and size on parsing success; it does not
1417  * update the passed in values on failure.
1418  *
1419  * Return 0 on success, < 0 on failure.
1420  */
1421 int acpi_dma_get_range(struct device *dev, u64 *dma_addr, u64 *offset,
1422 		       u64 *size)
1423 {
1424 	struct acpi_device *adev;
1425 	LIST_HEAD(list);
1426 	struct resource_entry *rentry;
1427 	int ret;
1428 	struct device *dma_dev = dev;
1429 	u64 len, dma_start = U64_MAX, dma_end = 0, dma_offset = 0;
1430 
1431 	/*
1432 	 * Walk the device tree chasing an ACPI companion with a _DMA
1433 	 * object while we go. Stop if we find a device with an ACPI
1434 	 * companion containing a _DMA method.
1435 	 */
1436 	do {
1437 		adev = ACPI_COMPANION(dma_dev);
1438 		if (adev && acpi_has_method(adev->handle, METHOD_NAME__DMA))
1439 			break;
1440 
1441 		dma_dev = dma_dev->parent;
1442 	} while (dma_dev);
1443 
1444 	if (!dma_dev)
1445 		return -ENODEV;
1446 
1447 	if (!acpi_has_method(adev->handle, METHOD_NAME__CRS)) {
1448 		acpi_handle_warn(adev->handle, "_DMA is valid only if _CRS is present\n");
1449 		return -EINVAL;
1450 	}
1451 
1452 	ret = acpi_dev_get_dma_resources(adev, &list);
1453 	if (ret > 0) {
1454 		list_for_each_entry(rentry, &list, node) {
1455 			if (dma_offset && rentry->offset != dma_offset) {
1456 				ret = -EINVAL;
1457 				dev_warn(dma_dev, "Can't handle multiple windows with different offsets\n");
1458 				goto out;
1459 			}
1460 			dma_offset = rentry->offset;
1461 
1462 			/* Take lower and upper limits */
1463 			if (rentry->res->start < dma_start)
1464 				dma_start = rentry->res->start;
1465 			if (rentry->res->end > dma_end)
1466 				dma_end = rentry->res->end;
1467 		}
1468 
1469 		if (dma_start >= dma_end) {
1470 			ret = -EINVAL;
1471 			dev_dbg(dma_dev, "Invalid DMA regions configuration\n");
1472 			goto out;
1473 		}
1474 
1475 		*dma_addr = dma_start - dma_offset;
1476 		len = dma_end - dma_start;
1477 		*size = max(len, len + 1);
1478 		*offset = dma_offset;
1479 	}
1480  out:
1481 	acpi_dev_free_resource_list(&list);
1482 
1483 	return ret >= 0 ? 0 : ret;
1484 }
1485 
1486 /**
1487  * acpi_dma_configure_id - Set-up DMA configuration for the device.
1488  * @dev: The pointer to the device
1489  * @attr: device dma attributes
1490  * @input_id: input device id const value pointer
1491  */
1492 int acpi_dma_configure_id(struct device *dev, enum dev_dma_attr attr,
1493 			  const u32 *input_id)
1494 {
1495 	const struct iommu_ops *iommu;
1496 	u64 dma_addr = 0, size = 0;
1497 
1498 	if (attr == DEV_DMA_NOT_SUPPORTED) {
1499 		set_dma_ops(dev, &dma_dummy_ops);
1500 		return 0;
1501 	}
1502 
1503 	iort_dma_setup(dev, &dma_addr, &size);
1504 
1505 	iommu = iort_iommu_configure_id(dev, input_id);
1506 	if (PTR_ERR(iommu) == -EPROBE_DEFER)
1507 		return -EPROBE_DEFER;
1508 
1509 	arch_setup_dma_ops(dev, dma_addr, size,
1510 				iommu, attr == DEV_DMA_COHERENT);
1511 
1512 	return 0;
1513 }
1514 EXPORT_SYMBOL_GPL(acpi_dma_configure_id);
1515 
1516 static void acpi_init_coherency(struct acpi_device *adev)
1517 {
1518 	unsigned long long cca = 0;
1519 	acpi_status status;
1520 	struct acpi_device *parent = adev->parent;
1521 
1522 	if (parent && parent->flags.cca_seen) {
1523 		/*
1524 		 * From ACPI spec, OSPM will ignore _CCA if an ancestor
1525 		 * already saw one.
1526 		 */
1527 		adev->flags.cca_seen = 1;
1528 		cca = parent->flags.coherent_dma;
1529 	} else {
1530 		status = acpi_evaluate_integer(adev->handle, "_CCA",
1531 					       NULL, &cca);
1532 		if (ACPI_SUCCESS(status))
1533 			adev->flags.cca_seen = 1;
1534 		else if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1535 			/*
1536 			 * If architecture does not specify that _CCA is
1537 			 * required for DMA-able devices (e.g. x86),
1538 			 * we default to _CCA=1.
1539 			 */
1540 			cca = 1;
1541 		else
1542 			acpi_handle_debug(adev->handle,
1543 					  "ACPI device is missing _CCA.\n");
1544 	}
1545 
1546 	adev->flags.coherent_dma = cca;
1547 }
1548 
1549 static int acpi_check_serial_bus_slave(struct acpi_resource *ares, void *data)
1550 {
1551 	bool *is_serial_bus_slave_p = data;
1552 
1553 	if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
1554 		return 1;
1555 
1556 	*is_serial_bus_slave_p = true;
1557 
1558 	 /* no need to do more checking */
1559 	return -1;
1560 }
1561 
1562 static bool acpi_is_indirect_io_slave(struct acpi_device *device)
1563 {
1564 	struct acpi_device *parent = device->parent;
1565 	static const struct acpi_device_id indirect_io_hosts[] = {
1566 		{"HISI0191", 0},
1567 		{}
1568 	};
1569 
1570 	return parent && !acpi_match_device_ids(parent, indirect_io_hosts);
1571 }
1572 
1573 static bool acpi_device_enumeration_by_parent(struct acpi_device *device)
1574 {
1575 	struct list_head resource_list;
1576 	bool is_serial_bus_slave = false;
1577 	/*
1578 	 * These devices have multiple I2cSerialBus resources and an i2c-client
1579 	 * must be instantiated for each, each with its own i2c_device_id.
1580 	 * Normally we only instantiate an i2c-client for the first resource,
1581 	 * using the ACPI HID as id. These special cases are handled by the
1582 	 * drivers/platform/x86/i2c-multi-instantiate.c driver, which knows
1583 	 * which i2c_device_id to use for each resource.
1584 	 */
1585 	static const struct acpi_device_id i2c_multi_instantiate_ids[] = {
1586 		{"BSG1160", },
1587 		{"BSG2150", },
1588 		{"INT33FE", },
1589 		{"INT3515", },
1590 		{}
1591 	};
1592 
1593 	if (acpi_is_indirect_io_slave(device))
1594 		return true;
1595 
1596 	/* Macs use device properties in lieu of _CRS resources */
1597 	if (x86_apple_machine &&
1598 	    (fwnode_property_present(&device->fwnode, "spiSclkPeriod") ||
1599 	     fwnode_property_present(&device->fwnode, "i2cAddress") ||
1600 	     fwnode_property_present(&device->fwnode, "baud")))
1601 		return true;
1602 
1603 	/* Instantiate a pdev for the i2c-multi-instantiate drv to bind to */
1604 	if (!acpi_match_device_ids(device, i2c_multi_instantiate_ids))
1605 		return false;
1606 
1607 	INIT_LIST_HEAD(&resource_list);
1608 	acpi_dev_get_resources(device, &resource_list,
1609 			       acpi_check_serial_bus_slave,
1610 			       &is_serial_bus_slave);
1611 	acpi_dev_free_resource_list(&resource_list);
1612 
1613 	return is_serial_bus_slave;
1614 }
1615 
1616 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1617 			     int type, unsigned long long sta,
1618 			     struct acpi_device_info *info)
1619 {
1620 	INIT_LIST_HEAD(&device->pnp.ids);
1621 	device->device_type = type;
1622 	device->handle = handle;
1623 	device->parent = acpi_bus_get_parent(handle);
1624 	fwnode_init(&device->fwnode, &acpi_device_fwnode_ops);
1625 	acpi_set_device_status(device, sta);
1626 	acpi_device_get_busid(device);
1627 	acpi_set_pnp_ids(handle, &device->pnp, type, info);
1628 	acpi_init_properties(device);
1629 	acpi_bus_get_flags(device);
1630 	device->flags.match_driver = false;
1631 	device->flags.initialized = true;
1632 	device->flags.enumeration_by_parent =
1633 		acpi_device_enumeration_by_parent(device);
1634 	acpi_device_clear_enumerated(device);
1635 	device_initialize(&device->dev);
1636 	dev_set_uevent_suppress(&device->dev, true);
1637 	acpi_init_coherency(device);
1638 	/* Assume there are unmet deps until acpi_device_dep_initialize() runs */
1639 	device->dep_unmet = 1;
1640 }
1641 
1642 void acpi_device_add_finalize(struct acpi_device *device)
1643 {
1644 	dev_set_uevent_suppress(&device->dev, false);
1645 	kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1646 }
1647 
1648 static int acpi_add_single_object(struct acpi_device **child,
1649 				  acpi_handle handle, int type,
1650 				  unsigned long long sta)
1651 {
1652 	int result;
1653 	struct acpi_device *device;
1654 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1655 	struct acpi_device_info *info = NULL;
1656 
1657 	if (handle != ACPI_ROOT_OBJECT && type == ACPI_BUS_TYPE_DEVICE)
1658 		acpi_get_object_info(handle, &info);
1659 
1660 	device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1661 	if (!device) {
1662 		printk(KERN_ERR PREFIX "Memory allocation error\n");
1663 		kfree(info);
1664 		return -ENOMEM;
1665 	}
1666 
1667 	acpi_init_device_object(device, handle, type, sta, info);
1668 	kfree(info);
1669 	/*
1670 	 * For ACPI_BUS_TYPE_DEVICE getting the status is delayed till here so
1671 	 * that we can call acpi_bus_get_status() and use its quirk handling.
1672 	 * Note this must be done before the get power-/wakeup_dev-flags calls.
1673 	 */
1674 	if (type == ACPI_BUS_TYPE_DEVICE)
1675 		if (acpi_bus_get_status(device) < 0)
1676 			acpi_set_device_status(device, 0);
1677 
1678 	acpi_bus_get_power_flags(device);
1679 	acpi_bus_get_wakeup_device_flags(device);
1680 
1681 	result = acpi_device_add(device, acpi_device_release);
1682 	if (result) {
1683 		acpi_device_release(&device->dev);
1684 		return result;
1685 	}
1686 
1687 	acpi_power_add_remove_device(device, true);
1688 	acpi_device_add_finalize(device);
1689 	acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1690 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1691 		dev_name(&device->dev), (char *) buffer.pointer,
1692 		device->parent ? dev_name(&device->parent->dev) : "(null)"));
1693 	kfree(buffer.pointer);
1694 	*child = device;
1695 	return 0;
1696 }
1697 
1698 static acpi_status acpi_get_resource_memory(struct acpi_resource *ares,
1699 					    void *context)
1700 {
1701 	struct resource *res = context;
1702 
1703 	if (acpi_dev_resource_memory(ares, res))
1704 		return AE_CTRL_TERMINATE;
1705 
1706 	return AE_OK;
1707 }
1708 
1709 static bool acpi_device_should_be_hidden(acpi_handle handle)
1710 {
1711 	acpi_status status;
1712 	struct resource res;
1713 
1714 	/* Check if it should ignore the UART device */
1715 	if (!(spcr_uart_addr && acpi_has_method(handle, METHOD_NAME__CRS)))
1716 		return false;
1717 
1718 	/*
1719 	 * The UART device described in SPCR table is assumed to have only one
1720 	 * memory resource present. So we only look for the first one here.
1721 	 */
1722 	status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1723 				     acpi_get_resource_memory, &res);
1724 	if (ACPI_FAILURE(status) || res.start != spcr_uart_addr)
1725 		return false;
1726 
1727 	acpi_handle_info(handle, "The UART device @%pa in SPCR table will be hidden\n",
1728 			 &res.start);
1729 
1730 	return true;
1731 }
1732 
1733 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1734 				    unsigned long long *sta)
1735 {
1736 	acpi_status status;
1737 	acpi_object_type acpi_type;
1738 
1739 	status = acpi_get_type(handle, &acpi_type);
1740 	if (ACPI_FAILURE(status))
1741 		return -ENODEV;
1742 
1743 	switch (acpi_type) {
1744 	case ACPI_TYPE_ANY:		/* for ACPI_ROOT_OBJECT */
1745 	case ACPI_TYPE_DEVICE:
1746 		if (acpi_device_should_be_hidden(handle))
1747 			return -ENODEV;
1748 
1749 		*type = ACPI_BUS_TYPE_DEVICE;
1750 		/*
1751 		 * acpi_add_single_object updates this once we've an acpi_device
1752 		 * so that acpi_bus_get_status' quirk handling can be used.
1753 		 */
1754 		*sta = ACPI_STA_DEFAULT;
1755 		break;
1756 	case ACPI_TYPE_PROCESSOR:
1757 		*type = ACPI_BUS_TYPE_PROCESSOR;
1758 		status = acpi_bus_get_status_handle(handle, sta);
1759 		if (ACPI_FAILURE(status))
1760 			return -ENODEV;
1761 		break;
1762 	case ACPI_TYPE_THERMAL:
1763 		*type = ACPI_BUS_TYPE_THERMAL;
1764 		*sta = ACPI_STA_DEFAULT;
1765 		break;
1766 	case ACPI_TYPE_POWER:
1767 		*type = ACPI_BUS_TYPE_POWER;
1768 		*sta = ACPI_STA_DEFAULT;
1769 		break;
1770 	default:
1771 		return -ENODEV;
1772 	}
1773 
1774 	return 0;
1775 }
1776 
1777 bool acpi_device_is_present(const struct acpi_device *adev)
1778 {
1779 	return adev->status.present || adev->status.functional;
1780 }
1781 
1782 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1783 				       const char *idstr,
1784 				       const struct acpi_device_id **matchid)
1785 {
1786 	const struct acpi_device_id *devid;
1787 
1788 	if (handler->match)
1789 		return handler->match(idstr, matchid);
1790 
1791 	for (devid = handler->ids; devid->id[0]; devid++)
1792 		if (!strcmp((char *)devid->id, idstr)) {
1793 			if (matchid)
1794 				*matchid = devid;
1795 
1796 			return true;
1797 		}
1798 
1799 	return false;
1800 }
1801 
1802 static struct acpi_scan_handler *acpi_scan_match_handler(const char *idstr,
1803 					const struct acpi_device_id **matchid)
1804 {
1805 	struct acpi_scan_handler *handler;
1806 
1807 	list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1808 		if (acpi_scan_handler_matching(handler, idstr, matchid))
1809 			return handler;
1810 
1811 	return NULL;
1812 }
1813 
1814 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1815 {
1816 	if (!!hotplug->enabled == !!val)
1817 		return;
1818 
1819 	mutex_lock(&acpi_scan_lock);
1820 
1821 	hotplug->enabled = val;
1822 
1823 	mutex_unlock(&acpi_scan_lock);
1824 }
1825 
1826 static void acpi_scan_init_hotplug(struct acpi_device *adev)
1827 {
1828 	struct acpi_hardware_id *hwid;
1829 
1830 	if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
1831 		acpi_dock_add(adev);
1832 		return;
1833 	}
1834 	list_for_each_entry(hwid, &adev->pnp.ids, list) {
1835 		struct acpi_scan_handler *handler;
1836 
1837 		handler = acpi_scan_match_handler(hwid->id, NULL);
1838 		if (handler) {
1839 			adev->flags.hotplug_notify = true;
1840 			break;
1841 		}
1842 	}
1843 }
1844 
1845 static void acpi_device_dep_initialize(struct acpi_device *adev)
1846 {
1847 	struct acpi_dep_data *dep;
1848 	struct acpi_handle_list dep_devices;
1849 	acpi_status status;
1850 	int i;
1851 
1852 	adev->dep_unmet = 0;
1853 
1854 	if (!acpi_has_method(adev->handle, "_DEP"))
1855 		return;
1856 
1857 	status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
1858 					&dep_devices);
1859 	if (ACPI_FAILURE(status)) {
1860 		dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
1861 		return;
1862 	}
1863 
1864 	for (i = 0; i < dep_devices.count; i++) {
1865 		struct acpi_device_info *info;
1866 		int skip;
1867 
1868 		status = acpi_get_object_info(dep_devices.handles[i], &info);
1869 		if (ACPI_FAILURE(status)) {
1870 			dev_dbg(&adev->dev, "Error reading _DEP device info\n");
1871 			continue;
1872 		}
1873 
1874 		skip = acpi_info_matches_ids(info, acpi_ignore_dep_ids);
1875 		kfree(info);
1876 
1877 		if (skip)
1878 			continue;
1879 
1880 		dep = kzalloc(sizeof(struct acpi_dep_data), GFP_KERNEL);
1881 		if (!dep)
1882 			return;
1883 
1884 		dep->supplier = dep_devices.handles[i];
1885 		dep->consumer  = adev->handle;
1886 		adev->dep_unmet++;
1887 
1888 		mutex_lock(&acpi_dep_list_lock);
1889 		list_add_tail(&dep->node , &acpi_dep_list);
1890 		mutex_unlock(&acpi_dep_list_lock);
1891 	}
1892 }
1893 
1894 static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
1895 				      void *not_used, void **return_value)
1896 {
1897 	struct acpi_device *device = NULL;
1898 	int type;
1899 	unsigned long long sta;
1900 	int result;
1901 
1902 	acpi_bus_get_device(handle, &device);
1903 	if (device)
1904 		goto out;
1905 
1906 	result = acpi_bus_type_and_status(handle, &type, &sta);
1907 	if (result)
1908 		return AE_OK;
1909 
1910 	if (type == ACPI_BUS_TYPE_POWER) {
1911 		acpi_add_power_resource(handle);
1912 		return AE_OK;
1913 	}
1914 
1915 	acpi_add_single_object(&device, handle, type, sta);
1916 	if (!device)
1917 		return AE_CTRL_DEPTH;
1918 
1919 	acpi_scan_init_hotplug(device);
1920 	acpi_device_dep_initialize(device);
1921 
1922  out:
1923 	if (!*return_value)
1924 		*return_value = device;
1925 
1926 	return AE_OK;
1927 }
1928 
1929 static void acpi_default_enumeration(struct acpi_device *device)
1930 {
1931 	/*
1932 	 * Do not enumerate devices with enumeration_by_parent flag set as
1933 	 * they will be enumerated by their respective parents.
1934 	 */
1935 	if (!device->flags.enumeration_by_parent) {
1936 		acpi_create_platform_device(device, NULL);
1937 		acpi_device_set_enumerated(device);
1938 	} else {
1939 		blocking_notifier_call_chain(&acpi_reconfig_chain,
1940 					     ACPI_RECONFIG_DEVICE_ADD, device);
1941 	}
1942 }
1943 
1944 static const struct acpi_device_id generic_device_ids[] = {
1945 	{ACPI_DT_NAMESPACE_HID, },
1946 	{"", },
1947 };
1948 
1949 static int acpi_generic_device_attach(struct acpi_device *adev,
1950 				      const struct acpi_device_id *not_used)
1951 {
1952 	/*
1953 	 * Since ACPI_DT_NAMESPACE_HID is the only ID handled here, the test
1954 	 * below can be unconditional.
1955 	 */
1956 	if (adev->data.of_compatible)
1957 		acpi_default_enumeration(adev);
1958 
1959 	return 1;
1960 }
1961 
1962 static struct acpi_scan_handler generic_device_handler = {
1963 	.ids = generic_device_ids,
1964 	.attach = acpi_generic_device_attach,
1965 };
1966 
1967 static int acpi_scan_attach_handler(struct acpi_device *device)
1968 {
1969 	struct acpi_hardware_id *hwid;
1970 	int ret = 0;
1971 
1972 	list_for_each_entry(hwid, &device->pnp.ids, list) {
1973 		const struct acpi_device_id *devid;
1974 		struct acpi_scan_handler *handler;
1975 
1976 		handler = acpi_scan_match_handler(hwid->id, &devid);
1977 		if (handler) {
1978 			if (!handler->attach) {
1979 				device->pnp.type.platform_id = 0;
1980 				continue;
1981 			}
1982 			device->handler = handler;
1983 			ret = handler->attach(device, devid);
1984 			if (ret > 0)
1985 				break;
1986 
1987 			device->handler = NULL;
1988 			if (ret < 0)
1989 				break;
1990 		}
1991 	}
1992 
1993 	return ret;
1994 }
1995 
1996 static void acpi_bus_attach(struct acpi_device *device)
1997 {
1998 	struct acpi_device *child;
1999 	acpi_handle ejd;
2000 	int ret;
2001 
2002 	if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
2003 		register_dock_dependent_device(device, ejd);
2004 
2005 	acpi_bus_get_status(device);
2006 	/* Skip devices that are not present. */
2007 	if (!acpi_device_is_present(device)) {
2008 		device->flags.initialized = false;
2009 		acpi_device_clear_enumerated(device);
2010 		device->flags.power_manageable = 0;
2011 		return;
2012 	}
2013 	if (device->handler)
2014 		goto ok;
2015 
2016 	if (!device->flags.initialized) {
2017 		device->flags.power_manageable =
2018 			device->power.states[ACPI_STATE_D0].flags.valid;
2019 		if (acpi_bus_init_power(device))
2020 			device->flags.power_manageable = 0;
2021 
2022 		device->flags.initialized = true;
2023 	} else if (device->flags.visited) {
2024 		goto ok;
2025 	}
2026 
2027 	ret = acpi_scan_attach_handler(device);
2028 	if (ret < 0)
2029 		return;
2030 
2031 	device->flags.match_driver = true;
2032 	if (ret > 0 && !device->flags.enumeration_by_parent) {
2033 		acpi_device_set_enumerated(device);
2034 		goto ok;
2035 	}
2036 
2037 	ret = device_attach(&device->dev);
2038 	if (ret < 0)
2039 		return;
2040 
2041 	if (device->pnp.type.platform_id || device->flags.enumeration_by_parent)
2042 		acpi_default_enumeration(device);
2043 	else
2044 		acpi_device_set_enumerated(device);
2045 
2046  ok:
2047 	list_for_each_entry(child, &device->children, node)
2048 		acpi_bus_attach(child);
2049 
2050 	if (device->handler && device->handler->hotplug.notify_online)
2051 		device->handler->hotplug.notify_online(device);
2052 }
2053 
2054 void acpi_walk_dep_device_list(acpi_handle handle)
2055 {
2056 	struct acpi_dep_data *dep, *tmp;
2057 	struct acpi_device *adev;
2058 
2059 	mutex_lock(&acpi_dep_list_lock);
2060 	list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
2061 		if (dep->supplier == handle) {
2062 			acpi_bus_get_device(dep->consumer, &adev);
2063 			if (!adev)
2064 				continue;
2065 
2066 			adev->dep_unmet--;
2067 			if (!adev->dep_unmet)
2068 				acpi_bus_attach(adev);
2069 			list_del(&dep->node);
2070 			kfree(dep);
2071 		}
2072 	}
2073 	mutex_unlock(&acpi_dep_list_lock);
2074 }
2075 EXPORT_SYMBOL_GPL(acpi_walk_dep_device_list);
2076 
2077 /**
2078  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
2079  * @handle: Root of the namespace scope to scan.
2080  *
2081  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
2082  * found devices.
2083  *
2084  * If no devices were found, -ENODEV is returned, but it does not mean that
2085  * there has been a real error.  There just have been no suitable ACPI objects
2086  * in the table trunk from which the kernel could create a device and add an
2087  * appropriate driver.
2088  *
2089  * Must be called under acpi_scan_lock.
2090  */
2091 int acpi_bus_scan(acpi_handle handle)
2092 {
2093 	void *device = NULL;
2094 
2095 	if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
2096 		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2097 				    acpi_bus_check_add, NULL, NULL, &device);
2098 
2099 	if (device) {
2100 		acpi_bus_attach(device);
2101 		return 0;
2102 	}
2103 	return -ENODEV;
2104 }
2105 EXPORT_SYMBOL(acpi_bus_scan);
2106 
2107 /**
2108  * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
2109  * @adev: Root of the ACPI namespace scope to walk.
2110  *
2111  * Must be called under acpi_scan_lock.
2112  */
2113 void acpi_bus_trim(struct acpi_device *adev)
2114 {
2115 	struct acpi_scan_handler *handler = adev->handler;
2116 	struct acpi_device *child;
2117 
2118 	list_for_each_entry_reverse(child, &adev->children, node)
2119 		acpi_bus_trim(child);
2120 
2121 	adev->flags.match_driver = false;
2122 	if (handler) {
2123 		if (handler->detach)
2124 			handler->detach(adev);
2125 
2126 		adev->handler = NULL;
2127 	} else {
2128 		device_release_driver(&adev->dev);
2129 	}
2130 	/*
2131 	 * Most likely, the device is going away, so put it into D3cold before
2132 	 * that.
2133 	 */
2134 	acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
2135 	adev->flags.initialized = false;
2136 	acpi_device_clear_enumerated(adev);
2137 }
2138 EXPORT_SYMBOL_GPL(acpi_bus_trim);
2139 
2140 int acpi_bus_register_early_device(int type)
2141 {
2142 	struct acpi_device *device = NULL;
2143 	int result;
2144 
2145 	result = acpi_add_single_object(&device, NULL,
2146 					type, ACPI_STA_DEFAULT);
2147 	if (result)
2148 		return result;
2149 
2150 	device->flags.match_driver = true;
2151 	return device_attach(&device->dev);
2152 }
2153 EXPORT_SYMBOL_GPL(acpi_bus_register_early_device);
2154 
2155 static int acpi_bus_scan_fixed(void)
2156 {
2157 	int result = 0;
2158 
2159 	/*
2160 	 * Enumerate all fixed-feature devices.
2161 	 */
2162 	if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2163 		struct acpi_device *device = NULL;
2164 
2165 		result = acpi_add_single_object(&device, NULL,
2166 						ACPI_BUS_TYPE_POWER_BUTTON,
2167 						ACPI_STA_DEFAULT);
2168 		if (result)
2169 			return result;
2170 
2171 		device->flags.match_driver = true;
2172 		result = device_attach(&device->dev);
2173 		if (result < 0)
2174 			return result;
2175 
2176 		device_init_wakeup(&device->dev, true);
2177 	}
2178 
2179 	if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2180 		struct acpi_device *device = NULL;
2181 
2182 		result = acpi_add_single_object(&device, NULL,
2183 						ACPI_BUS_TYPE_SLEEP_BUTTON,
2184 						ACPI_STA_DEFAULT);
2185 		if (result)
2186 			return result;
2187 
2188 		device->flags.match_driver = true;
2189 		result = device_attach(&device->dev);
2190 	}
2191 
2192 	return result < 0 ? result : 0;
2193 }
2194 
2195 static void __init acpi_get_spcr_uart_addr(void)
2196 {
2197 	acpi_status status;
2198 	struct acpi_table_spcr *spcr_ptr;
2199 
2200 	status = acpi_get_table(ACPI_SIG_SPCR, 0,
2201 				(struct acpi_table_header **)&spcr_ptr);
2202 	if (ACPI_FAILURE(status)) {
2203 		pr_warn(PREFIX "STAO table present, but SPCR is missing\n");
2204 		return;
2205 	}
2206 
2207 	spcr_uart_addr = spcr_ptr->serial_port.address;
2208 	acpi_put_table((struct acpi_table_header *)spcr_ptr);
2209 }
2210 
2211 static bool acpi_scan_initialized;
2212 
2213 int __init acpi_scan_init(void)
2214 {
2215 	int result;
2216 	acpi_status status;
2217 	struct acpi_table_stao *stao_ptr;
2218 
2219 	acpi_pci_root_init();
2220 	acpi_pci_link_init();
2221 	acpi_processor_init();
2222 	acpi_platform_init();
2223 	acpi_lpss_init();
2224 	acpi_apd_init();
2225 	acpi_cmos_rtc_init();
2226 	acpi_container_init();
2227 	acpi_memory_hotplug_init();
2228 	acpi_watchdog_init();
2229 	acpi_pnp_init();
2230 	acpi_int340x_thermal_init();
2231 	acpi_amba_init();
2232 	acpi_init_lpit();
2233 
2234 	acpi_scan_add_handler(&generic_device_handler);
2235 
2236 	/*
2237 	 * If there is STAO table, check whether it needs to ignore the UART
2238 	 * device in SPCR table.
2239 	 */
2240 	status = acpi_get_table(ACPI_SIG_STAO, 0,
2241 				(struct acpi_table_header **)&stao_ptr);
2242 	if (ACPI_SUCCESS(status)) {
2243 		if (stao_ptr->header.length > sizeof(struct acpi_table_stao))
2244 			pr_info(PREFIX "STAO Name List not yet supported.\n");
2245 
2246 		if (stao_ptr->ignore_uart)
2247 			acpi_get_spcr_uart_addr();
2248 
2249 		acpi_put_table((struct acpi_table_header *)stao_ptr);
2250 	}
2251 
2252 	acpi_gpe_apply_masked_gpes();
2253 	acpi_update_all_gpes();
2254 
2255 	/*
2256 	 * Although we call __add_memory() that is documented to require the
2257 	 * device_hotplug_lock, it is not necessary here because this is an
2258 	 * early code when userspace or any other code path cannot trigger
2259 	 * hotplug/hotunplug operations.
2260 	 */
2261 	mutex_lock(&acpi_scan_lock);
2262 	/*
2263 	 * Enumerate devices in the ACPI namespace.
2264 	 */
2265 	result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2266 	if (result)
2267 		goto out;
2268 
2269 	result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2270 	if (result)
2271 		goto out;
2272 
2273 	/* Fixed feature devices do not exist on HW-reduced platform */
2274 	if (!acpi_gbl_reduced_hardware) {
2275 		result = acpi_bus_scan_fixed();
2276 		if (result) {
2277 			acpi_detach_data(acpi_root->handle,
2278 					 acpi_scan_drop_device);
2279 			acpi_device_del(acpi_root);
2280 			put_device(&acpi_root->dev);
2281 			goto out;
2282 		}
2283 	}
2284 
2285 	acpi_scan_initialized = true;
2286 
2287  out:
2288 	mutex_unlock(&acpi_scan_lock);
2289 	return result;
2290 }
2291 
2292 static struct acpi_probe_entry *ape;
2293 static int acpi_probe_count;
2294 static DEFINE_MUTEX(acpi_probe_mutex);
2295 
2296 static int __init acpi_match_madt(union acpi_subtable_headers *header,
2297 				  const unsigned long end)
2298 {
2299 	if (!ape->subtable_valid || ape->subtable_valid(&header->common, ape))
2300 		if (!ape->probe_subtbl(header, end))
2301 			acpi_probe_count++;
2302 
2303 	return 0;
2304 }
2305 
2306 int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr)
2307 {
2308 	int count = 0;
2309 
2310 	if (acpi_disabled)
2311 		return 0;
2312 
2313 	mutex_lock(&acpi_probe_mutex);
2314 	for (ape = ap_head; nr; ape++, nr--) {
2315 		if (ACPI_COMPARE_NAMESEG(ACPI_SIG_MADT, ape->id)) {
2316 			acpi_probe_count = 0;
2317 			acpi_table_parse_madt(ape->type, acpi_match_madt, 0);
2318 			count += acpi_probe_count;
2319 		} else {
2320 			int res;
2321 			res = acpi_table_parse(ape->id, ape->probe_table);
2322 			if (!res)
2323 				count++;
2324 		}
2325 	}
2326 	mutex_unlock(&acpi_probe_mutex);
2327 
2328 	return count;
2329 }
2330 
2331 struct acpi_table_events_work {
2332 	struct work_struct work;
2333 	void *table;
2334 	u32 event;
2335 };
2336 
2337 static void acpi_table_events_fn(struct work_struct *work)
2338 {
2339 	struct acpi_table_events_work *tew;
2340 
2341 	tew = container_of(work, struct acpi_table_events_work, work);
2342 
2343 	if (tew->event == ACPI_TABLE_EVENT_LOAD) {
2344 		acpi_scan_lock_acquire();
2345 		acpi_bus_scan(ACPI_ROOT_OBJECT);
2346 		acpi_scan_lock_release();
2347 	}
2348 
2349 	kfree(tew);
2350 }
2351 
2352 void acpi_scan_table_handler(u32 event, void *table, void *context)
2353 {
2354 	struct acpi_table_events_work *tew;
2355 
2356 	if (!acpi_scan_initialized)
2357 		return;
2358 
2359 	if (event != ACPI_TABLE_EVENT_LOAD)
2360 		return;
2361 
2362 	tew = kmalloc(sizeof(*tew), GFP_KERNEL);
2363 	if (!tew)
2364 		return;
2365 
2366 	INIT_WORK(&tew->work, acpi_table_events_fn);
2367 	tew->table = table;
2368 	tew->event = event;
2369 
2370 	schedule_work(&tew->work);
2371 }
2372 
2373 int acpi_reconfig_notifier_register(struct notifier_block *nb)
2374 {
2375 	return blocking_notifier_chain_register(&acpi_reconfig_chain, nb);
2376 }
2377 EXPORT_SYMBOL(acpi_reconfig_notifier_register);
2378 
2379 int acpi_reconfig_notifier_unregister(struct notifier_block *nb)
2380 {
2381 	return blocking_notifier_chain_unregister(&acpi_reconfig_chain, nb);
2382 }
2383 EXPORT_SYMBOL(acpi_reconfig_notifier_unregister);
2384