xref: /linux/drivers/acpi/scan.c (revision bfb921b2a9d5d1123d1d10b196a39db629ddef87)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * scan.c - support for transforming the ACPI namespace into individual objects
4  */
5 
6 #define pr_fmt(fmt) "ACPI: " fmt
7 
8 #include <linux/module.h>
9 #include <linux/init.h>
10 #include <linux/slab.h>
11 #include <linux/kernel.h>
12 #include <linux/acpi.h>
13 #include <linux/acpi_iort.h>
14 #include <linux/acpi_viot.h>
15 #include <linux/iommu.h>
16 #include <linux/signal.h>
17 #include <linux/kthread.h>
18 #include <linux/dmi.h>
19 #include <linux/dma-map-ops.h>
20 #include <linux/platform_data/x86/apple.h>
21 #include <linux/pgtable.h>
22 #include <linux/crc32.h>
23 #include <linux/dma-direct.h>
24 
25 #include "internal.h"
26 #include "sleep.h"
27 
28 #define ACPI_BUS_CLASS			"system_bus"
29 #define ACPI_BUS_HID			"LNXSYBUS"
30 #define ACPI_BUS_DEVICE_NAME		"System Bus"
31 
32 #define INVALID_ACPI_HANDLE	((acpi_handle)ZERO_PAGE(0))
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 void acpi_scan_lock_acquire(void)
53 {
54 	mutex_lock(&acpi_scan_lock);
55 }
56 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
57 
58 void acpi_scan_lock_release(void)
59 {
60 	mutex_unlock(&acpi_scan_lock);
61 }
62 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
63 
64 void acpi_lock_hp_context(void)
65 {
66 	mutex_lock(&acpi_hp_context_lock);
67 }
68 
69 void acpi_unlock_hp_context(void)
70 {
71 	mutex_unlock(&acpi_hp_context_lock);
72 }
73 
74 void acpi_initialize_hp_context(struct acpi_device *adev,
75 				struct acpi_hotplug_context *hp,
76 				acpi_hp_notify notify, acpi_hp_uevent uevent)
77 {
78 	acpi_lock_hp_context();
79 	hp->notify = notify;
80 	hp->uevent = uevent;
81 	acpi_set_hp_context(adev, hp);
82 	acpi_unlock_hp_context();
83 }
84 EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
85 
86 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
87 {
88 	if (!handler)
89 		return -EINVAL;
90 
91 	list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
92 	return 0;
93 }
94 
95 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
96 				       const char *hotplug_profile_name)
97 {
98 	int error;
99 
100 	error = acpi_scan_add_handler(handler);
101 	if (error)
102 		return error;
103 
104 	acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
105 	return 0;
106 }
107 
108 bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
109 {
110 	struct acpi_device_physical_node *pn;
111 	bool offline = true;
112 	char *envp[] = { "EVENT=offline", NULL };
113 
114 	/*
115 	 * acpi_container_offline() calls this for all of the container's
116 	 * children under the container's physical_node_lock lock.
117 	 */
118 	mutex_lock_nested(&adev->physical_node_lock, SINGLE_DEPTH_NESTING);
119 
120 	list_for_each_entry(pn, &adev->physical_node_list, node)
121 		if (device_supports_offline(pn->dev) && !pn->dev->offline) {
122 			if (uevent)
123 				kobject_uevent_env(&pn->dev->kobj, KOBJ_CHANGE, envp);
124 
125 			offline = false;
126 			break;
127 		}
128 
129 	mutex_unlock(&adev->physical_node_lock);
130 	return offline;
131 }
132 
133 static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
134 				    void **ret_p)
135 {
136 	struct acpi_device *device = acpi_fetch_acpi_dev(handle);
137 	struct acpi_device_physical_node *pn;
138 	bool second_pass = (bool)data;
139 	acpi_status status = AE_OK;
140 
141 	if (!device)
142 		return AE_OK;
143 
144 	if (device->handler && !device->handler->hotplug.enabled) {
145 		*ret_p = &device->dev;
146 		return AE_SUPPORT;
147 	}
148 
149 	mutex_lock(&device->physical_node_lock);
150 
151 	list_for_each_entry(pn, &device->physical_node_list, node) {
152 		int ret;
153 
154 		if (second_pass) {
155 			/* Skip devices offlined by the first pass. */
156 			if (pn->put_online)
157 				continue;
158 		} else {
159 			pn->put_online = false;
160 		}
161 		ret = device_offline(pn->dev);
162 		if (ret >= 0) {
163 			pn->put_online = !ret;
164 		} else {
165 			*ret_p = pn->dev;
166 			if (second_pass) {
167 				status = AE_ERROR;
168 				break;
169 			}
170 		}
171 	}
172 
173 	mutex_unlock(&device->physical_node_lock);
174 
175 	return status;
176 }
177 
178 static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
179 				   void **ret_p)
180 {
181 	struct acpi_device *device = acpi_fetch_acpi_dev(handle);
182 	struct acpi_device_physical_node *pn;
183 
184 	if (!device)
185 		return AE_OK;
186 
187 	mutex_lock(&device->physical_node_lock);
188 
189 	list_for_each_entry(pn, &device->physical_node_list, node)
190 		if (pn->put_online) {
191 			device_online(pn->dev);
192 			pn->put_online = false;
193 		}
194 
195 	mutex_unlock(&device->physical_node_lock);
196 
197 	return AE_OK;
198 }
199 
200 static int acpi_scan_try_to_offline(struct acpi_device *device)
201 {
202 	acpi_handle handle = device->handle;
203 	struct device *errdev = NULL;
204 	acpi_status status;
205 
206 	/*
207 	 * Carry out two passes here and ignore errors in the first pass,
208 	 * because if the devices in question are memory blocks and
209 	 * CONFIG_MEMCG is set, one of the blocks may hold data structures
210 	 * that the other blocks depend on, but it is not known in advance which
211 	 * block holds them.
212 	 *
213 	 * If the first pass is successful, the second one isn't needed, though.
214 	 */
215 	status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
216 				     NULL, acpi_bus_offline, (void *)false,
217 				     (void **)&errdev);
218 	if (status == AE_SUPPORT) {
219 		dev_warn(errdev, "Offline disabled.\n");
220 		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
221 				    acpi_bus_online, NULL, NULL, NULL);
222 		return -EPERM;
223 	}
224 	acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
225 	if (errdev) {
226 		errdev = NULL;
227 		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
228 				    NULL, acpi_bus_offline, (void *)true,
229 				    (void **)&errdev);
230 		if (!errdev)
231 			acpi_bus_offline(handle, 0, (void *)true,
232 					 (void **)&errdev);
233 
234 		if (errdev) {
235 			dev_warn(errdev, "Offline failed.\n");
236 			acpi_bus_online(handle, 0, NULL, NULL);
237 			acpi_walk_namespace(ACPI_TYPE_ANY, handle,
238 					    ACPI_UINT32_MAX, acpi_bus_online,
239 					    NULL, NULL, NULL);
240 			return -EBUSY;
241 		}
242 	}
243 	return 0;
244 }
245 
246 static int acpi_scan_check_and_detach(struct acpi_device *adev, void *check)
247 {
248 	struct acpi_scan_handler *handler = adev->handler;
249 
250 	acpi_dev_for_each_child_reverse(adev, acpi_scan_check_and_detach, check);
251 
252 	if (check) {
253 		acpi_bus_get_status(adev);
254 		/*
255 		 * Skip devices that are still there and take the enabled
256 		 * flag into account.
257 		 */
258 		if (acpi_device_is_enabled(adev))
259 			return 0;
260 
261 		/* Skip device that have not been enumerated. */
262 		if (!acpi_device_enumerated(adev)) {
263 			dev_dbg(&adev->dev, "Still not enumerated\n");
264 			return 0;
265 		}
266 	}
267 
268 	adev->flags.match_driver = false;
269 	if (handler) {
270 		if (handler->detach)
271 			handler->detach(adev);
272 
273 		adev->handler = NULL;
274 	} else {
275 		device_release_driver(&adev->dev);
276 	}
277 	/*
278 	 * Most likely, the device is going away, so put it into D3cold before
279 	 * that.
280 	 */
281 	acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
282 	adev->flags.initialized = false;
283 	acpi_device_clear_enumerated(adev);
284 
285 	return 0;
286 }
287 
288 static void acpi_scan_check_subtree(struct acpi_device *adev)
289 {
290 	acpi_scan_check_and_detach(adev, (void *)true);
291 }
292 
293 static int acpi_scan_hot_remove(struct acpi_device *device)
294 {
295 	acpi_handle handle = device->handle;
296 	unsigned long long sta;
297 	acpi_status status;
298 
299 	if (device->handler && device->handler->hotplug.demand_offline) {
300 		if (!acpi_scan_is_offline(device, true))
301 			return -EBUSY;
302 	} else {
303 		int error = acpi_scan_try_to_offline(device);
304 		if (error)
305 			return error;
306 	}
307 
308 	acpi_handle_debug(handle, "Ejecting\n");
309 
310 	acpi_bus_trim(device);
311 
312 	acpi_evaluate_lck(handle, 0);
313 	/*
314 	 * TBD: _EJD support.
315 	 */
316 	status = acpi_evaluate_ej0(handle);
317 	if (status == AE_NOT_FOUND)
318 		return -ENODEV;
319 	else if (ACPI_FAILURE(status))
320 		return -EIO;
321 
322 	/*
323 	 * Verify if eject was indeed successful.  If not, log an error
324 	 * message.  No need to call _OST since _EJ0 call was made OK.
325 	 */
326 	status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
327 	if (ACPI_FAILURE(status)) {
328 		acpi_handle_warn(handle,
329 			"Status check after eject failed (0x%x)\n", status);
330 	} else if (sta & ACPI_STA_DEVICE_ENABLED) {
331 		acpi_handle_warn(handle,
332 			"Eject incomplete - status 0x%llx\n", sta);
333 	}
334 
335 	return 0;
336 }
337 
338 static int acpi_scan_rescan_bus(struct acpi_device *adev)
339 {
340 	struct acpi_scan_handler *handler = adev->handler;
341 	int ret;
342 
343 	if (handler && handler->hotplug.scan_dependent)
344 		ret = handler->hotplug.scan_dependent(adev);
345 	else
346 		ret = acpi_bus_scan(adev->handle);
347 
348 	if (ret)
349 		dev_info(&adev->dev, "Namespace scan failure\n");
350 
351 	return ret;
352 }
353 
354 static int acpi_scan_device_check(struct acpi_device *adev)
355 {
356 	struct acpi_device *parent;
357 
358 	acpi_scan_check_subtree(adev);
359 
360 	if (!acpi_device_is_present(adev))
361 		return 0;
362 
363 	/*
364 	 * This function is only called for device objects for which matching
365 	 * scan handlers exist.  The only situation in which the scan handler
366 	 * is not attached to this device object yet is when the device has
367 	 * just appeared (either it wasn't present at all before or it was
368 	 * removed and then added again).
369 	 */
370 	if (adev->handler) {
371 		dev_dbg(&adev->dev, "Already enumerated\n");
372 		return 0;
373 	}
374 
375 	parent = acpi_dev_parent(adev);
376 	if (!parent)
377 		parent = adev;
378 
379 	return acpi_scan_rescan_bus(parent);
380 }
381 
382 static int acpi_scan_bus_check(struct acpi_device *adev)
383 {
384 	acpi_scan_check_subtree(adev);
385 
386 	return acpi_scan_rescan_bus(adev);
387 }
388 
389 static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type)
390 {
391 	switch (type) {
392 	case ACPI_NOTIFY_BUS_CHECK:
393 		return acpi_scan_bus_check(adev);
394 	case ACPI_NOTIFY_DEVICE_CHECK:
395 		return acpi_scan_device_check(adev);
396 	case ACPI_NOTIFY_EJECT_REQUEST:
397 	case ACPI_OST_EC_OSPM_EJECT:
398 		if (adev->handler && !adev->handler->hotplug.enabled) {
399 			dev_info(&adev->dev, "Eject disabled\n");
400 			return -EPERM;
401 		}
402 		acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST,
403 				  ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
404 		return acpi_scan_hot_remove(adev);
405 	}
406 	return -EINVAL;
407 }
408 
409 void acpi_device_hotplug(struct acpi_device *adev, u32 src)
410 {
411 	u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
412 	int error = -ENODEV;
413 
414 	lock_device_hotplug();
415 	mutex_lock(&acpi_scan_lock);
416 
417 	/*
418 	 * The device object's ACPI handle cannot become invalid as long as we
419 	 * are holding acpi_scan_lock, but it might have become invalid before
420 	 * that lock was acquired.
421 	 */
422 	if (adev->handle == INVALID_ACPI_HANDLE)
423 		goto err_out;
424 
425 	if (adev->flags.is_dock_station) {
426 		error = dock_notify(adev, src);
427 	} else if (adev->flags.hotplug_notify) {
428 		error = acpi_generic_hotplug_event(adev, src);
429 	} else {
430 		acpi_hp_notify notify;
431 
432 		acpi_lock_hp_context();
433 		notify = adev->hp ? adev->hp->notify : NULL;
434 		acpi_unlock_hp_context();
435 		/*
436 		 * There may be additional notify handlers for device objects
437 		 * without the .event() callback, so ignore them here.
438 		 */
439 		if (notify)
440 			error = notify(adev, src);
441 		else
442 			goto out;
443 	}
444 	switch (error) {
445 	case 0:
446 		ost_code = ACPI_OST_SC_SUCCESS;
447 		break;
448 	case -EPERM:
449 		ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
450 		break;
451 	case -EBUSY:
452 		ost_code = ACPI_OST_SC_DEVICE_BUSY;
453 		break;
454 	default:
455 		ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
456 		break;
457 	}
458 
459  err_out:
460 	acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
461 
462  out:
463 	acpi_put_acpi_dev(adev);
464 	mutex_unlock(&acpi_scan_lock);
465 	unlock_device_hotplug();
466 }
467 
468 static void acpi_free_power_resources_lists(struct acpi_device *device)
469 {
470 	int i;
471 
472 	if (device->wakeup.flags.valid)
473 		acpi_power_resources_list_free(&device->wakeup.resources);
474 
475 	if (!device->power.flags.power_resources)
476 		return;
477 
478 	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
479 		struct acpi_device_power_state *ps = &device->power.states[i];
480 		acpi_power_resources_list_free(&ps->resources);
481 	}
482 }
483 
484 static void acpi_device_release(struct device *dev)
485 {
486 	struct acpi_device *acpi_dev = to_acpi_device(dev);
487 
488 	acpi_free_properties(acpi_dev);
489 	acpi_free_pnp_ids(&acpi_dev->pnp);
490 	acpi_free_power_resources_lists(acpi_dev);
491 	kfree(acpi_dev);
492 }
493 
494 static void acpi_device_del(struct acpi_device *device)
495 {
496 	struct acpi_device_bus_id *acpi_device_bus_id;
497 
498 	mutex_lock(&acpi_device_lock);
499 
500 	list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node)
501 		if (!strcmp(acpi_device_bus_id->bus_id,
502 			    acpi_device_hid(device))) {
503 			ida_free(&acpi_device_bus_id->instance_ida,
504 				 device->pnp.instance_no);
505 			if (ida_is_empty(&acpi_device_bus_id->instance_ida)) {
506 				list_del(&acpi_device_bus_id->node);
507 				kfree_const(acpi_device_bus_id->bus_id);
508 				kfree(acpi_device_bus_id);
509 			}
510 			break;
511 		}
512 
513 	list_del(&device->wakeup_list);
514 
515 	mutex_unlock(&acpi_device_lock);
516 
517 	acpi_power_add_remove_device(device, false);
518 	acpi_device_remove_files(device);
519 	if (device->remove)
520 		device->remove(device);
521 
522 	device_del(&device->dev);
523 }
524 
525 static BLOCKING_NOTIFIER_HEAD(acpi_reconfig_chain);
526 
527 static LIST_HEAD(acpi_device_del_list);
528 static DEFINE_MUTEX(acpi_device_del_lock);
529 
530 static void acpi_device_del_work_fn(struct work_struct *work_not_used)
531 {
532 	for (;;) {
533 		struct acpi_device *adev;
534 
535 		mutex_lock(&acpi_device_del_lock);
536 
537 		if (list_empty(&acpi_device_del_list)) {
538 			mutex_unlock(&acpi_device_del_lock);
539 			break;
540 		}
541 		adev = list_first_entry(&acpi_device_del_list,
542 					struct acpi_device, del_list);
543 		list_del(&adev->del_list);
544 
545 		mutex_unlock(&acpi_device_del_lock);
546 
547 		blocking_notifier_call_chain(&acpi_reconfig_chain,
548 					     ACPI_RECONFIG_DEVICE_REMOVE, adev);
549 
550 		acpi_device_del(adev);
551 		/*
552 		 * Drop references to all power resources that might have been
553 		 * used by the device.
554 		 */
555 		acpi_power_transition(adev, ACPI_STATE_D3_COLD);
556 		acpi_dev_put(adev);
557 	}
558 }
559 
560 /**
561  * acpi_scan_drop_device - Drop an ACPI device object.
562  * @handle: Handle of an ACPI namespace node, not used.
563  * @context: Address of the ACPI device object to drop.
564  *
565  * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
566  * namespace node the device object pointed to by @context is attached to.
567  *
568  * The unregistration is carried out asynchronously to avoid running
569  * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
570  * ensure the correct ordering (the device objects must be unregistered in the
571  * same order in which the corresponding namespace nodes are deleted).
572  */
573 static void acpi_scan_drop_device(acpi_handle handle, void *context)
574 {
575 	static DECLARE_WORK(work, acpi_device_del_work_fn);
576 	struct acpi_device *adev = context;
577 
578 	mutex_lock(&acpi_device_del_lock);
579 
580 	/*
581 	 * Use the ACPI hotplug workqueue which is ordered, so this work item
582 	 * won't run after any hotplug work items submitted subsequently.  That
583 	 * prevents attempts to register device objects identical to those being
584 	 * deleted from happening concurrently (such attempts result from
585 	 * hotplug events handled via the ACPI hotplug workqueue).  It also will
586 	 * run after all of the work items submitted previously, which helps
587 	 * those work items to ensure that they are not accessing stale device
588 	 * objects.
589 	 */
590 	if (list_empty(&acpi_device_del_list))
591 		acpi_queue_hotplug_work(&work);
592 
593 	list_add_tail(&adev->del_list, &acpi_device_del_list);
594 	/* Make acpi_ns_validate_handle() return NULL for this handle. */
595 	adev->handle = INVALID_ACPI_HANDLE;
596 
597 	mutex_unlock(&acpi_device_del_lock);
598 }
599 
600 static struct acpi_device *handle_to_device(acpi_handle handle,
601 					    void (*callback)(void *))
602 {
603 	struct acpi_device *adev = NULL;
604 	acpi_status status;
605 
606 	status = acpi_get_data_full(handle, acpi_scan_drop_device,
607 				    (void **)&adev, callback);
608 	if (ACPI_FAILURE(status) || !adev) {
609 		acpi_handle_debug(handle, "No context!\n");
610 		return NULL;
611 	}
612 	return adev;
613 }
614 
615 /**
616  * acpi_fetch_acpi_dev - Retrieve ACPI device object.
617  * @handle: ACPI handle associated with the requested ACPI device object.
618  *
619  * Return a pointer to the ACPI device object associated with @handle, if
620  * present, or NULL otherwise.
621  */
622 struct acpi_device *acpi_fetch_acpi_dev(acpi_handle handle)
623 {
624 	return handle_to_device(handle, NULL);
625 }
626 EXPORT_SYMBOL_GPL(acpi_fetch_acpi_dev);
627 
628 static void get_acpi_device(void *dev)
629 {
630 	acpi_dev_get(dev);
631 }
632 
633 /**
634  * acpi_get_acpi_dev - Retrieve ACPI device object and reference count it.
635  * @handle: ACPI handle associated with the requested ACPI device object.
636  *
637  * Return a pointer to the ACPI device object associated with @handle and bump
638  * up that object's reference counter (under the ACPI Namespace lock), if
639  * present, or return NULL otherwise.
640  *
641  * The ACPI device object reference acquired by this function needs to be
642  * dropped via acpi_dev_put().
643  */
644 struct acpi_device *acpi_get_acpi_dev(acpi_handle handle)
645 {
646 	return handle_to_device(handle, get_acpi_device);
647 }
648 EXPORT_SYMBOL_GPL(acpi_get_acpi_dev);
649 
650 static struct acpi_device_bus_id *acpi_device_bus_id_match(const char *dev_id)
651 {
652 	struct acpi_device_bus_id *acpi_device_bus_id;
653 
654 	/* Find suitable bus_id and instance number in acpi_bus_id_list. */
655 	list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
656 		if (!strcmp(acpi_device_bus_id->bus_id, dev_id))
657 			return acpi_device_bus_id;
658 	}
659 	return NULL;
660 }
661 
662 static int acpi_device_set_name(struct acpi_device *device,
663 				struct acpi_device_bus_id *acpi_device_bus_id)
664 {
665 	struct ida *instance_ida = &acpi_device_bus_id->instance_ida;
666 	int result;
667 
668 	result = ida_alloc(instance_ida, GFP_KERNEL);
669 	if (result < 0)
670 		return result;
671 
672 	device->pnp.instance_no = result;
673 	dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, result);
674 	return 0;
675 }
676 
677 int acpi_tie_acpi_dev(struct acpi_device *adev)
678 {
679 	acpi_handle handle = adev->handle;
680 	acpi_status status;
681 
682 	if (!handle)
683 		return 0;
684 
685 	status = acpi_attach_data(handle, acpi_scan_drop_device, adev);
686 	if (ACPI_FAILURE(status)) {
687 		acpi_handle_err(handle, "Unable to attach device data\n");
688 		return -ENODEV;
689 	}
690 
691 	return 0;
692 }
693 
694 static void acpi_store_pld_crc(struct acpi_device *adev)
695 {
696 	struct acpi_pld_info *pld;
697 	acpi_status status;
698 
699 	status = acpi_get_physical_device_location(adev->handle, &pld);
700 	if (ACPI_FAILURE(status))
701 		return;
702 
703 	adev->pld_crc = crc32(~0, pld, sizeof(*pld));
704 	ACPI_FREE(pld);
705 }
706 
707 int acpi_device_add(struct acpi_device *device)
708 {
709 	struct acpi_device_bus_id *acpi_device_bus_id;
710 	int result;
711 
712 	/*
713 	 * Linkage
714 	 * -------
715 	 * Link this device to its parent and siblings.
716 	 */
717 	INIT_LIST_HEAD(&device->wakeup_list);
718 	INIT_LIST_HEAD(&device->physical_node_list);
719 	INIT_LIST_HEAD(&device->del_list);
720 	mutex_init(&device->physical_node_lock);
721 
722 	mutex_lock(&acpi_device_lock);
723 
724 	acpi_device_bus_id = acpi_device_bus_id_match(acpi_device_hid(device));
725 	if (acpi_device_bus_id) {
726 		result = acpi_device_set_name(device, acpi_device_bus_id);
727 		if (result)
728 			goto err_unlock;
729 	} else {
730 		acpi_device_bus_id = kzalloc(sizeof(*acpi_device_bus_id),
731 					     GFP_KERNEL);
732 		if (!acpi_device_bus_id) {
733 			result = -ENOMEM;
734 			goto err_unlock;
735 		}
736 		acpi_device_bus_id->bus_id =
737 			kstrdup_const(acpi_device_hid(device), GFP_KERNEL);
738 		if (!acpi_device_bus_id->bus_id) {
739 			kfree(acpi_device_bus_id);
740 			result = -ENOMEM;
741 			goto err_unlock;
742 		}
743 
744 		ida_init(&acpi_device_bus_id->instance_ida);
745 
746 		result = acpi_device_set_name(device, acpi_device_bus_id);
747 		if (result) {
748 			kfree_const(acpi_device_bus_id->bus_id);
749 			kfree(acpi_device_bus_id);
750 			goto err_unlock;
751 		}
752 
753 		list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
754 	}
755 
756 	if (device->wakeup.flags.valid)
757 		list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
758 
759 	acpi_store_pld_crc(device);
760 
761 	mutex_unlock(&acpi_device_lock);
762 
763 	result = device_add(&device->dev);
764 	if (result) {
765 		dev_err(&device->dev, "Error registering device\n");
766 		goto err;
767 	}
768 
769 	result = acpi_device_setup_files(device);
770 	if (result)
771 		pr_err("Error creating sysfs interface for device %s\n",
772 		       dev_name(&device->dev));
773 
774 	return 0;
775 
776 err:
777 	mutex_lock(&acpi_device_lock);
778 
779 	list_del(&device->wakeup_list);
780 
781 err_unlock:
782 	mutex_unlock(&acpi_device_lock);
783 
784 	acpi_detach_data(device->handle, acpi_scan_drop_device);
785 
786 	return result;
787 }
788 
789 /* --------------------------------------------------------------------------
790                                  Device Enumeration
791    -------------------------------------------------------------------------- */
792 static bool acpi_info_matches_ids(struct acpi_device_info *info,
793 				  const char * const ids[])
794 {
795 	struct acpi_pnp_device_id_list *cid_list = NULL;
796 	int i, index;
797 
798 	if (!(info->valid & ACPI_VALID_HID))
799 		return false;
800 
801 	index = match_string(ids, -1, info->hardware_id.string);
802 	if (index >= 0)
803 		return true;
804 
805 	if (info->valid & ACPI_VALID_CID)
806 		cid_list = &info->compatible_id_list;
807 
808 	if (!cid_list)
809 		return false;
810 
811 	for (i = 0; i < cid_list->count; i++) {
812 		index = match_string(ids, -1, cid_list->ids[i].string);
813 		if (index >= 0)
814 			return true;
815 	}
816 
817 	return false;
818 }
819 
820 /* List of HIDs for which we ignore matching ACPI devices, when checking _DEP lists. */
821 static const char * const acpi_ignore_dep_ids[] = {
822 	"PNP0D80", /* Windows-compatible System Power Management Controller */
823 	"INT33BD", /* Intel Baytrail Mailbox Device */
824 	"LATT2021", /* Lattice FW Update Client Driver */
825 	NULL
826 };
827 
828 /* List of HIDs for which we honor deps of matching ACPI devs, when checking _DEP lists. */
829 static const char * const acpi_honor_dep_ids[] = {
830 	"INT3472", /* Camera sensor PMIC / clk and regulator info */
831 	"INTC1059", /* IVSC (TGL) driver must be loaded to allow i2c access to camera sensors */
832 	"INTC1095", /* IVSC (ADL) driver must be loaded to allow i2c access to camera sensors */
833 	"INTC100A", /* IVSC (RPL) driver must be loaded to allow i2c access to camera sensors */
834 	"INTC10CF", /* IVSC (MTL) driver must be loaded to allow i2c access to camera sensors */
835 	NULL
836 };
837 
838 static struct acpi_device *acpi_find_parent_acpi_dev(acpi_handle handle)
839 {
840 	struct acpi_device *adev;
841 
842 	/*
843 	 * Fixed hardware devices do not appear in the namespace and do not
844 	 * have handles, but we fabricate acpi_devices for them, so we have
845 	 * to deal with them specially.
846 	 */
847 	if (!handle)
848 		return acpi_root;
849 
850 	do {
851 		acpi_status status;
852 
853 		status = acpi_get_parent(handle, &handle);
854 		if (ACPI_FAILURE(status)) {
855 			if (status != AE_NULL_ENTRY)
856 				return acpi_root;
857 
858 			return NULL;
859 		}
860 		adev = acpi_fetch_acpi_dev(handle);
861 	} while (!adev);
862 	return adev;
863 }
864 
865 acpi_status
866 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
867 {
868 	acpi_status status;
869 	acpi_handle tmp;
870 	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
871 	union acpi_object *obj;
872 
873 	status = acpi_get_handle(handle, "_EJD", &tmp);
874 	if (ACPI_FAILURE(status))
875 		return status;
876 
877 	status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
878 	if (ACPI_SUCCESS(status)) {
879 		obj = buffer.pointer;
880 		status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
881 					 ejd);
882 		kfree(buffer.pointer);
883 	}
884 	return status;
885 }
886 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
887 
888 static int acpi_bus_extract_wakeup_device_power_package(struct acpi_device *dev)
889 {
890 	acpi_handle handle = dev->handle;
891 	struct acpi_device_wakeup *wakeup = &dev->wakeup;
892 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
893 	union acpi_object *package = NULL;
894 	union acpi_object *element = NULL;
895 	acpi_status status;
896 	int err = -ENODATA;
897 
898 	INIT_LIST_HEAD(&wakeup->resources);
899 
900 	/* _PRW */
901 	status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
902 	if (ACPI_FAILURE(status)) {
903 		acpi_handle_info(handle, "_PRW evaluation failed: %s\n",
904 				 acpi_format_exception(status));
905 		return err;
906 	}
907 
908 	package = (union acpi_object *)buffer.pointer;
909 
910 	if (!package || package->package.count < 2)
911 		goto out;
912 
913 	element = &(package->package.elements[0]);
914 	if (!element)
915 		goto out;
916 
917 	if (element->type == ACPI_TYPE_PACKAGE) {
918 		if ((element->package.count < 2) ||
919 		    (element->package.elements[0].type !=
920 		     ACPI_TYPE_LOCAL_REFERENCE)
921 		    || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
922 			goto out;
923 
924 		wakeup->gpe_device =
925 		    element->package.elements[0].reference.handle;
926 		wakeup->gpe_number =
927 		    (u32) element->package.elements[1].integer.value;
928 	} else if (element->type == ACPI_TYPE_INTEGER) {
929 		wakeup->gpe_device = NULL;
930 		wakeup->gpe_number = element->integer.value;
931 	} else {
932 		goto out;
933 	}
934 
935 	element = &(package->package.elements[1]);
936 	if (element->type != ACPI_TYPE_INTEGER)
937 		goto out;
938 
939 	wakeup->sleep_state = element->integer.value;
940 
941 	err = acpi_extract_power_resources(package, 2, &wakeup->resources);
942 	if (err)
943 		goto out;
944 
945 	if (!list_empty(&wakeup->resources)) {
946 		int sleep_state;
947 
948 		err = acpi_power_wakeup_list_init(&wakeup->resources,
949 						  &sleep_state);
950 		if (err) {
951 			acpi_handle_warn(handle, "Retrieving current states "
952 					 "of wakeup power resources failed\n");
953 			acpi_power_resources_list_free(&wakeup->resources);
954 			goto out;
955 		}
956 		if (sleep_state < wakeup->sleep_state) {
957 			acpi_handle_warn(handle, "Overriding _PRW sleep state "
958 					 "(S%d) by S%d from power resources\n",
959 					 (int)wakeup->sleep_state, sleep_state);
960 			wakeup->sleep_state = sleep_state;
961 		}
962 	}
963 
964  out:
965 	kfree(buffer.pointer);
966 	return err;
967 }
968 
969 /* Do not use a button for S5 wakeup */
970 #define ACPI_AVOID_WAKE_FROM_S5		BIT(0)
971 
972 static bool acpi_wakeup_gpe_init(struct acpi_device *device)
973 {
974 	static const struct acpi_device_id button_device_ids[] = {
975 		{"PNP0C0C", 0},				/* Power button */
976 		{"PNP0C0D", ACPI_AVOID_WAKE_FROM_S5},	/* Lid */
977 		{"PNP0C0E", ACPI_AVOID_WAKE_FROM_S5},	/* Sleep button */
978 		{"", 0},
979 	};
980 	struct acpi_device_wakeup *wakeup = &device->wakeup;
981 	const struct acpi_device_id *match;
982 	acpi_status status;
983 
984 	wakeup->flags.notifier_present = 0;
985 
986 	/* Power button, Lid switch always enable wakeup */
987 	match = acpi_match_acpi_device(button_device_ids, device);
988 	if (match) {
989 		if ((match->driver_data & ACPI_AVOID_WAKE_FROM_S5) &&
990 		    wakeup->sleep_state == ACPI_STATE_S5)
991 			wakeup->sleep_state = ACPI_STATE_S4;
992 		acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
993 		device_set_wakeup_capable(&device->dev, true);
994 		return true;
995 	}
996 
997 	status = acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
998 					 wakeup->gpe_number);
999 	return ACPI_SUCCESS(status);
1000 }
1001 
1002 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
1003 {
1004 	int err;
1005 
1006 	/* Presence of _PRW indicates wake capable */
1007 	if (!acpi_has_method(device->handle, "_PRW"))
1008 		return;
1009 
1010 	err = acpi_bus_extract_wakeup_device_power_package(device);
1011 	if (err) {
1012 		dev_err(&device->dev, "Unable to extract wakeup power resources");
1013 		return;
1014 	}
1015 
1016 	device->wakeup.flags.valid = acpi_wakeup_gpe_init(device);
1017 	device->wakeup.prepare_count = 0;
1018 	/*
1019 	 * Call _PSW/_DSW object to disable its ability to wake the sleeping
1020 	 * system for the ACPI device with the _PRW object.
1021 	 * The _PSW object is deprecated in ACPI 3.0 and is replaced by _DSW.
1022 	 * So it is necessary to call _DSW object first. Only when it is not
1023 	 * present will the _PSW object used.
1024 	 */
1025 	err = acpi_device_sleep_wake(device, 0, 0, 0);
1026 	if (err)
1027 		pr_debug("error in _DSW or _PSW evaluation\n");
1028 }
1029 
1030 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
1031 {
1032 	struct acpi_device_power_state *ps = &device->power.states[state];
1033 	char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
1034 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1035 	acpi_status status;
1036 
1037 	INIT_LIST_HEAD(&ps->resources);
1038 
1039 	/* Evaluate "_PRx" to get referenced power resources */
1040 	status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
1041 	if (ACPI_SUCCESS(status)) {
1042 		union acpi_object *package = buffer.pointer;
1043 
1044 		if (buffer.length && package
1045 		    && package->type == ACPI_TYPE_PACKAGE
1046 		    && package->package.count)
1047 			acpi_extract_power_resources(package, 0, &ps->resources);
1048 
1049 		ACPI_FREE(buffer.pointer);
1050 	}
1051 
1052 	/* Evaluate "_PSx" to see if we can do explicit sets */
1053 	pathname[2] = 'S';
1054 	if (acpi_has_method(device->handle, pathname))
1055 		ps->flags.explicit_set = 1;
1056 
1057 	/* State is valid if there are means to put the device into it. */
1058 	if (!list_empty(&ps->resources) || ps->flags.explicit_set)
1059 		ps->flags.valid = 1;
1060 
1061 	ps->power = -1;		/* Unknown - driver assigned */
1062 	ps->latency = -1;	/* Unknown - driver assigned */
1063 }
1064 
1065 static void acpi_bus_get_power_flags(struct acpi_device *device)
1066 {
1067 	unsigned long long dsc = ACPI_STATE_D0;
1068 	u32 i;
1069 
1070 	/* Presence of _PS0|_PR0 indicates 'power manageable' */
1071 	if (!acpi_has_method(device->handle, "_PS0") &&
1072 	    !acpi_has_method(device->handle, "_PR0"))
1073 		return;
1074 
1075 	device->flags.power_manageable = 1;
1076 
1077 	/*
1078 	 * Power Management Flags
1079 	 */
1080 	if (acpi_has_method(device->handle, "_PSC"))
1081 		device->power.flags.explicit_get = 1;
1082 
1083 	if (acpi_has_method(device->handle, "_IRC"))
1084 		device->power.flags.inrush_current = 1;
1085 
1086 	if (acpi_has_method(device->handle, "_DSW"))
1087 		device->power.flags.dsw_present = 1;
1088 
1089 	acpi_evaluate_integer(device->handle, "_DSC", NULL, &dsc);
1090 	device->power.state_for_enumeration = dsc;
1091 
1092 	/*
1093 	 * Enumerate supported power management states
1094 	 */
1095 	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
1096 		acpi_bus_init_power_state(device, i);
1097 
1098 	INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
1099 
1100 	/* Set the defaults for D0 and D3hot (always supported). */
1101 	device->power.states[ACPI_STATE_D0].flags.valid = 1;
1102 	device->power.states[ACPI_STATE_D0].power = 100;
1103 	device->power.states[ACPI_STATE_D3_HOT].flags.valid = 1;
1104 
1105 	/*
1106 	 * Use power resources only if the D0 list of them is populated, because
1107 	 * some platforms may provide _PR3 only to indicate D3cold support and
1108 	 * in those cases the power resources list returned by it may be bogus.
1109 	 */
1110 	if (!list_empty(&device->power.states[ACPI_STATE_D0].resources)) {
1111 		device->power.flags.power_resources = 1;
1112 		/*
1113 		 * D3cold is supported if the D3hot list of power resources is
1114 		 * not empty.
1115 		 */
1116 		if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources))
1117 			device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
1118 	}
1119 
1120 	if (acpi_bus_init_power(device))
1121 		device->flags.power_manageable = 0;
1122 }
1123 
1124 static void acpi_bus_get_flags(struct acpi_device *device)
1125 {
1126 	/* Presence of _STA indicates 'dynamic_status' */
1127 	if (acpi_has_method(device->handle, "_STA"))
1128 		device->flags.dynamic_status = 1;
1129 
1130 	/* Presence of _RMV indicates 'removable' */
1131 	if (acpi_has_method(device->handle, "_RMV"))
1132 		device->flags.removable = 1;
1133 
1134 	/* Presence of _EJD|_EJ0 indicates 'ejectable' */
1135 	if (acpi_has_method(device->handle, "_EJD") ||
1136 	    acpi_has_method(device->handle, "_EJ0"))
1137 		device->flags.ejectable = 1;
1138 }
1139 
1140 static void acpi_device_get_busid(struct acpi_device *device)
1141 {
1142 	char bus_id[5] = { '?', 0 };
1143 	struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1144 	int i = 0;
1145 
1146 	/*
1147 	 * Bus ID
1148 	 * ------
1149 	 * The device's Bus ID is simply the object name.
1150 	 * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1151 	 */
1152 	if (!acpi_dev_parent(device)) {
1153 		strcpy(device->pnp.bus_id, "ACPI");
1154 		return;
1155 	}
1156 
1157 	switch (device->device_type) {
1158 	case ACPI_BUS_TYPE_POWER_BUTTON:
1159 		strcpy(device->pnp.bus_id, "PWRF");
1160 		break;
1161 	case ACPI_BUS_TYPE_SLEEP_BUTTON:
1162 		strcpy(device->pnp.bus_id, "SLPF");
1163 		break;
1164 	case ACPI_BUS_TYPE_ECDT_EC:
1165 		strcpy(device->pnp.bus_id, "ECDT");
1166 		break;
1167 	default:
1168 		acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1169 		/* Clean up trailing underscores (if any) */
1170 		for (i = 3; i > 1; i--) {
1171 			if (bus_id[i] == '_')
1172 				bus_id[i] = '\0';
1173 			else
1174 				break;
1175 		}
1176 		strcpy(device->pnp.bus_id, bus_id);
1177 		break;
1178 	}
1179 }
1180 
1181 /*
1182  * acpi_ata_match - see if an acpi object is an ATA device
1183  *
1184  * If an acpi object has one of the ACPI ATA methods defined,
1185  * then we can safely call it an ATA device.
1186  */
1187 bool acpi_ata_match(acpi_handle handle)
1188 {
1189 	return acpi_has_method(handle, "_GTF") ||
1190 	       acpi_has_method(handle, "_GTM") ||
1191 	       acpi_has_method(handle, "_STM") ||
1192 	       acpi_has_method(handle, "_SDD");
1193 }
1194 
1195 /*
1196  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1197  *
1198  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1199  * then we can safely call it an ejectable drive bay
1200  */
1201 bool acpi_bay_match(acpi_handle handle)
1202 {
1203 	acpi_handle phandle;
1204 
1205 	if (!acpi_has_method(handle, "_EJ0"))
1206 		return false;
1207 	if (acpi_ata_match(handle))
1208 		return true;
1209 	if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1210 		return false;
1211 
1212 	return acpi_ata_match(phandle);
1213 }
1214 
1215 bool acpi_device_is_battery(struct acpi_device *adev)
1216 {
1217 	struct acpi_hardware_id *hwid;
1218 
1219 	list_for_each_entry(hwid, &adev->pnp.ids, list)
1220 		if (!strcmp("PNP0C0A", hwid->id))
1221 			return true;
1222 
1223 	return false;
1224 }
1225 
1226 static bool is_ejectable_bay(struct acpi_device *adev)
1227 {
1228 	acpi_handle handle = adev->handle;
1229 
1230 	if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
1231 		return true;
1232 
1233 	return acpi_bay_match(handle);
1234 }
1235 
1236 /*
1237  * acpi_dock_match - see if an acpi object has a _DCK method
1238  */
1239 bool acpi_dock_match(acpi_handle handle)
1240 {
1241 	return acpi_has_method(handle, "_DCK");
1242 }
1243 
1244 static acpi_status
1245 acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
1246 			  void **return_value)
1247 {
1248 	long *cap = context;
1249 
1250 	if (acpi_has_method(handle, "_BCM") &&
1251 	    acpi_has_method(handle, "_BCL")) {
1252 		acpi_handle_debug(handle, "Found generic backlight support\n");
1253 		*cap |= ACPI_VIDEO_BACKLIGHT;
1254 		/* We have backlight support, no need to scan further */
1255 		return AE_CTRL_TERMINATE;
1256 	}
1257 	return 0;
1258 }
1259 
1260 /* Returns true if the ACPI object is a video device which can be
1261  * handled by video.ko.
1262  * The device will get a Linux specific CID added in scan.c to
1263  * identify the device as an ACPI graphics device
1264  * Be aware that the graphics device may not be physically present
1265  * Use acpi_video_get_capabilities() to detect general ACPI video
1266  * capabilities of present cards
1267  */
1268 long acpi_is_video_device(acpi_handle handle)
1269 {
1270 	long video_caps = 0;
1271 
1272 	/* Is this device able to support video switching ? */
1273 	if (acpi_has_method(handle, "_DOD") || acpi_has_method(handle, "_DOS"))
1274 		video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
1275 
1276 	/* Is this device able to retrieve a video ROM ? */
1277 	if (acpi_has_method(handle, "_ROM"))
1278 		video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
1279 
1280 	/* Is this device able to configure which video head to be POSTed ? */
1281 	if (acpi_has_method(handle, "_VPO") &&
1282 	    acpi_has_method(handle, "_GPD") &&
1283 	    acpi_has_method(handle, "_SPD"))
1284 		video_caps |= ACPI_VIDEO_DEVICE_POSTING;
1285 
1286 	/* Only check for backlight functionality if one of the above hit. */
1287 	if (video_caps)
1288 		acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
1289 				    ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
1290 				    &video_caps, NULL);
1291 
1292 	return video_caps;
1293 }
1294 EXPORT_SYMBOL(acpi_is_video_device);
1295 
1296 const char *acpi_device_hid(struct acpi_device *device)
1297 {
1298 	struct acpi_hardware_id *hid;
1299 
1300 	hid = list_first_entry_or_null(&device->pnp.ids, struct acpi_hardware_id, list);
1301 	if (!hid)
1302 		return dummy_hid;
1303 
1304 	return hid->id;
1305 }
1306 EXPORT_SYMBOL(acpi_device_hid);
1307 
1308 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1309 {
1310 	struct acpi_hardware_id *id;
1311 
1312 	id = kmalloc(sizeof(*id), GFP_KERNEL);
1313 	if (!id)
1314 		return;
1315 
1316 	id->id = kstrdup_const(dev_id, GFP_KERNEL);
1317 	if (!id->id) {
1318 		kfree(id);
1319 		return;
1320 	}
1321 
1322 	list_add_tail(&id->list, &pnp->ids);
1323 	pnp->type.hardware_id = 1;
1324 }
1325 
1326 /*
1327  * Old IBM workstations have a DSDT bug wherein the SMBus object
1328  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1329  * prefix.  Work around this.
1330  */
1331 static bool acpi_ibm_smbus_match(acpi_handle handle)
1332 {
1333 	char node_name[ACPI_PATH_SEGMENT_LENGTH];
1334 	struct acpi_buffer path = { sizeof(node_name), node_name };
1335 
1336 	if (!dmi_name_in_vendors("IBM"))
1337 		return false;
1338 
1339 	/* Look for SMBS object */
1340 	if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1341 	    strcmp("SMBS", path.pointer))
1342 		return false;
1343 
1344 	/* Does it have the necessary (but misnamed) methods? */
1345 	if (acpi_has_method(handle, "SBI") &&
1346 	    acpi_has_method(handle, "SBR") &&
1347 	    acpi_has_method(handle, "SBW"))
1348 		return true;
1349 
1350 	return false;
1351 }
1352 
1353 static bool acpi_object_is_system_bus(acpi_handle handle)
1354 {
1355 	acpi_handle tmp;
1356 
1357 	if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
1358 	    tmp == handle)
1359 		return true;
1360 	if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
1361 	    tmp == handle)
1362 		return true;
1363 
1364 	return false;
1365 }
1366 
1367 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1368 			     int device_type)
1369 {
1370 	struct acpi_device_info *info = NULL;
1371 	struct acpi_pnp_device_id_list *cid_list;
1372 	int i;
1373 
1374 	switch (device_type) {
1375 	case ACPI_BUS_TYPE_DEVICE:
1376 		if (handle == ACPI_ROOT_OBJECT) {
1377 			acpi_add_id(pnp, ACPI_SYSTEM_HID);
1378 			break;
1379 		}
1380 
1381 		acpi_get_object_info(handle, &info);
1382 		if (!info) {
1383 			pr_err("%s: Error reading device info\n", __func__);
1384 			return;
1385 		}
1386 
1387 		if (info->valid & ACPI_VALID_HID) {
1388 			acpi_add_id(pnp, info->hardware_id.string);
1389 			pnp->type.platform_id = 1;
1390 		}
1391 		if (info->valid & ACPI_VALID_CID) {
1392 			cid_list = &info->compatible_id_list;
1393 			for (i = 0; i < cid_list->count; i++)
1394 				acpi_add_id(pnp, cid_list->ids[i].string);
1395 		}
1396 		if (info->valid & ACPI_VALID_ADR) {
1397 			pnp->bus_address = info->address;
1398 			pnp->type.bus_address = 1;
1399 		}
1400 		if (info->valid & ACPI_VALID_UID)
1401 			pnp->unique_id = kstrdup(info->unique_id.string,
1402 							GFP_KERNEL);
1403 		if (info->valid & ACPI_VALID_CLS)
1404 			acpi_add_id(pnp, info->class_code.string);
1405 
1406 		kfree(info);
1407 
1408 		/*
1409 		 * Some devices don't reliably have _HIDs & _CIDs, so add
1410 		 * synthetic HIDs to make sure drivers can find them.
1411 		 */
1412 		if (acpi_is_video_device(handle)) {
1413 			acpi_add_id(pnp, ACPI_VIDEO_HID);
1414 			pnp->type.backlight = 1;
1415 			break;
1416 		}
1417 		if (acpi_bay_match(handle))
1418 			acpi_add_id(pnp, ACPI_BAY_HID);
1419 		else if (acpi_dock_match(handle))
1420 			acpi_add_id(pnp, ACPI_DOCK_HID);
1421 		else if (acpi_ibm_smbus_match(handle))
1422 			acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1423 		else if (list_empty(&pnp->ids) &&
1424 			 acpi_object_is_system_bus(handle)) {
1425 			/* \_SB, \_TZ, LNXSYBUS */
1426 			acpi_add_id(pnp, ACPI_BUS_HID);
1427 			strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1428 			strcpy(pnp->device_class, ACPI_BUS_CLASS);
1429 		}
1430 
1431 		break;
1432 	case ACPI_BUS_TYPE_POWER:
1433 		acpi_add_id(pnp, ACPI_POWER_HID);
1434 		break;
1435 	case ACPI_BUS_TYPE_PROCESSOR:
1436 		acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1437 		break;
1438 	case ACPI_BUS_TYPE_THERMAL:
1439 		acpi_add_id(pnp, ACPI_THERMAL_HID);
1440 		break;
1441 	case ACPI_BUS_TYPE_POWER_BUTTON:
1442 		acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1443 		break;
1444 	case ACPI_BUS_TYPE_SLEEP_BUTTON:
1445 		acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1446 		break;
1447 	case ACPI_BUS_TYPE_ECDT_EC:
1448 		acpi_add_id(pnp, ACPI_ECDT_HID);
1449 		break;
1450 	}
1451 }
1452 
1453 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1454 {
1455 	struct acpi_hardware_id *id, *tmp;
1456 
1457 	list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1458 		kfree_const(id->id);
1459 		kfree(id);
1460 	}
1461 	kfree(pnp->unique_id);
1462 }
1463 
1464 /**
1465  * acpi_dma_supported - Check DMA support for the specified device.
1466  * @adev: The pointer to acpi device
1467  *
1468  * Return false if DMA is not supported. Otherwise, return true
1469  */
1470 bool acpi_dma_supported(const struct acpi_device *adev)
1471 {
1472 	if (!adev)
1473 		return false;
1474 
1475 	if (adev->flags.cca_seen)
1476 		return true;
1477 
1478 	/*
1479 	* Per ACPI 6.0 sec 6.2.17, assume devices can do cache-coherent
1480 	* DMA on "Intel platforms".  Presumably that includes all x86 and
1481 	* ia64, and other arches will set CONFIG_ACPI_CCA_REQUIRED=y.
1482 	*/
1483 	if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1484 		return true;
1485 
1486 	return false;
1487 }
1488 
1489 /**
1490  * acpi_get_dma_attr - Check the supported DMA attr for the specified device.
1491  * @adev: The pointer to acpi device
1492  *
1493  * Return enum dev_dma_attr.
1494  */
1495 enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
1496 {
1497 	if (!acpi_dma_supported(adev))
1498 		return DEV_DMA_NOT_SUPPORTED;
1499 
1500 	if (adev->flags.coherent_dma)
1501 		return DEV_DMA_COHERENT;
1502 	else
1503 		return DEV_DMA_NON_COHERENT;
1504 }
1505 
1506 /**
1507  * acpi_dma_get_range() - Get device DMA parameters.
1508  *
1509  * @dev: device to configure
1510  * @map: pointer to DMA ranges result
1511  *
1512  * Evaluate DMA regions and return pointer to DMA regions on
1513  * parsing success; it does not update the passed in values on failure.
1514  *
1515  * Return 0 on success, < 0 on failure.
1516  */
1517 int acpi_dma_get_range(struct device *dev, const struct bus_dma_region **map)
1518 {
1519 	struct acpi_device *adev;
1520 	LIST_HEAD(list);
1521 	struct resource_entry *rentry;
1522 	int ret;
1523 	struct device *dma_dev = dev;
1524 	struct bus_dma_region *r;
1525 
1526 	/*
1527 	 * Walk the device tree chasing an ACPI companion with a _DMA
1528 	 * object while we go. Stop if we find a device with an ACPI
1529 	 * companion containing a _DMA method.
1530 	 */
1531 	do {
1532 		adev = ACPI_COMPANION(dma_dev);
1533 		if (adev && acpi_has_method(adev->handle, METHOD_NAME__DMA))
1534 			break;
1535 
1536 		dma_dev = dma_dev->parent;
1537 	} while (dma_dev);
1538 
1539 	if (!dma_dev)
1540 		return -ENODEV;
1541 
1542 	if (!acpi_has_method(adev->handle, METHOD_NAME__CRS)) {
1543 		acpi_handle_warn(adev->handle, "_DMA is valid only if _CRS is present\n");
1544 		return -EINVAL;
1545 	}
1546 
1547 	ret = acpi_dev_get_dma_resources(adev, &list);
1548 	if (ret > 0) {
1549 		r = kcalloc(ret + 1, sizeof(*r), GFP_KERNEL);
1550 		if (!r) {
1551 			ret = -ENOMEM;
1552 			goto out;
1553 		}
1554 
1555 		*map = r;
1556 
1557 		list_for_each_entry(rentry, &list, node) {
1558 			if (rentry->res->start >= rentry->res->end) {
1559 				kfree(*map);
1560 				*map = NULL;
1561 				ret = -EINVAL;
1562 				dev_dbg(dma_dev, "Invalid DMA regions configuration\n");
1563 				goto out;
1564 			}
1565 
1566 			r->cpu_start = rentry->res->start;
1567 			r->dma_start = rentry->res->start - rentry->offset;
1568 			r->size = resource_size(rentry->res);
1569 			r++;
1570 		}
1571 	}
1572  out:
1573 	acpi_dev_free_resource_list(&list);
1574 
1575 	return ret >= 0 ? 0 : ret;
1576 }
1577 
1578 #ifdef CONFIG_IOMMU_API
1579 int acpi_iommu_fwspec_init(struct device *dev, u32 id,
1580 			   struct fwnode_handle *fwnode,
1581 			   const struct iommu_ops *ops)
1582 {
1583 	int ret;
1584 
1585 	ret = iommu_fwspec_init(dev, fwnode, ops);
1586 	if (ret)
1587 		return ret;
1588 
1589 	return iommu_fwspec_add_ids(dev, &id, 1);
1590 }
1591 
1592 static inline const struct iommu_ops *acpi_iommu_fwspec_ops(struct device *dev)
1593 {
1594 	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
1595 
1596 	return fwspec ? fwspec->ops : NULL;
1597 }
1598 
1599 static int acpi_iommu_configure_id(struct device *dev, const u32 *id_in)
1600 {
1601 	int err;
1602 	const struct iommu_ops *ops;
1603 
1604 	/* Serialise to make dev->iommu stable under our potential fwspec */
1605 	mutex_lock(&iommu_probe_device_lock);
1606 	/*
1607 	 * If we already translated the fwspec there is nothing left to do,
1608 	 * return the iommu_ops.
1609 	 */
1610 	ops = acpi_iommu_fwspec_ops(dev);
1611 	if (ops) {
1612 		mutex_unlock(&iommu_probe_device_lock);
1613 		return 0;
1614 	}
1615 
1616 	err = iort_iommu_configure_id(dev, id_in);
1617 	if (err && err != -EPROBE_DEFER)
1618 		err = viot_iommu_configure(dev);
1619 	mutex_unlock(&iommu_probe_device_lock);
1620 
1621 	/*
1622 	 * If we have reason to believe the IOMMU driver missed the initial
1623 	 * iommu_probe_device() call for dev, replay it to get things in order.
1624 	 */
1625 	if (!err && dev->bus)
1626 		err = iommu_probe_device(dev);
1627 
1628 	if (err == -EPROBE_DEFER)
1629 		return err;
1630 	if (err) {
1631 		dev_dbg(dev, "Adding to IOMMU failed: %d\n", err);
1632 		return err;
1633 	}
1634 	if (!acpi_iommu_fwspec_ops(dev))
1635 		return -ENODEV;
1636 	return 0;
1637 }
1638 
1639 #else /* !CONFIG_IOMMU_API */
1640 
1641 int acpi_iommu_fwspec_init(struct device *dev, u32 id,
1642 			   struct fwnode_handle *fwnode,
1643 			   const struct iommu_ops *ops)
1644 {
1645 	return -ENODEV;
1646 }
1647 
1648 static int acpi_iommu_configure_id(struct device *dev, const u32 *id_in)
1649 {
1650 	return -ENODEV;
1651 }
1652 
1653 #endif /* !CONFIG_IOMMU_API */
1654 
1655 /**
1656  * acpi_dma_configure_id - Set-up DMA configuration for the device.
1657  * @dev: The pointer to the device
1658  * @attr: device dma attributes
1659  * @input_id: input device id const value pointer
1660  */
1661 int acpi_dma_configure_id(struct device *dev, enum dev_dma_attr attr,
1662 			  const u32 *input_id)
1663 {
1664 	int ret;
1665 
1666 	if (attr == DEV_DMA_NOT_SUPPORTED) {
1667 		set_dma_ops(dev, &dma_dummy_ops);
1668 		return 0;
1669 	}
1670 
1671 	acpi_arch_dma_setup(dev);
1672 
1673 	/* Ignore all other errors apart from EPROBE_DEFER */
1674 	ret = acpi_iommu_configure_id(dev, input_id);
1675 	if (ret == -EPROBE_DEFER)
1676 		return -EPROBE_DEFER;
1677 
1678 	arch_setup_dma_ops(dev, attr == DEV_DMA_COHERENT);
1679 
1680 	return 0;
1681 }
1682 EXPORT_SYMBOL_GPL(acpi_dma_configure_id);
1683 
1684 static void acpi_init_coherency(struct acpi_device *adev)
1685 {
1686 	unsigned long long cca = 0;
1687 	acpi_status status;
1688 	struct acpi_device *parent = acpi_dev_parent(adev);
1689 
1690 	if (parent && parent->flags.cca_seen) {
1691 		/*
1692 		 * From ACPI spec, OSPM will ignore _CCA if an ancestor
1693 		 * already saw one.
1694 		 */
1695 		adev->flags.cca_seen = 1;
1696 		cca = parent->flags.coherent_dma;
1697 	} else {
1698 		status = acpi_evaluate_integer(adev->handle, "_CCA",
1699 					       NULL, &cca);
1700 		if (ACPI_SUCCESS(status))
1701 			adev->flags.cca_seen = 1;
1702 		else if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1703 			/*
1704 			 * If architecture does not specify that _CCA is
1705 			 * required for DMA-able devices (e.g. x86),
1706 			 * we default to _CCA=1.
1707 			 */
1708 			cca = 1;
1709 		else
1710 			acpi_handle_debug(adev->handle,
1711 					  "ACPI device is missing _CCA.\n");
1712 	}
1713 
1714 	adev->flags.coherent_dma = cca;
1715 }
1716 
1717 static int acpi_check_serial_bus_slave(struct acpi_resource *ares, void *data)
1718 {
1719 	bool *is_serial_bus_slave_p = data;
1720 
1721 	if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
1722 		return 1;
1723 
1724 	*is_serial_bus_slave_p = true;
1725 
1726 	 /* no need to do more checking */
1727 	return -1;
1728 }
1729 
1730 static bool acpi_is_indirect_io_slave(struct acpi_device *device)
1731 {
1732 	struct acpi_device *parent = acpi_dev_parent(device);
1733 	static const struct acpi_device_id indirect_io_hosts[] = {
1734 		{"HISI0191", 0},
1735 		{}
1736 	};
1737 
1738 	return parent && !acpi_match_device_ids(parent, indirect_io_hosts);
1739 }
1740 
1741 static bool acpi_device_enumeration_by_parent(struct acpi_device *device)
1742 {
1743 	struct list_head resource_list;
1744 	bool is_serial_bus_slave = false;
1745 	static const struct acpi_device_id ignore_serial_bus_ids[] = {
1746 	/*
1747 	 * These devices have multiple SerialBus resources and a client
1748 	 * device must be instantiated for each of them, each with
1749 	 * its own device id.
1750 	 * Normally we only instantiate one client device for the first
1751 	 * resource, using the ACPI HID as id. These special cases are handled
1752 	 * by the drivers/platform/x86/serial-multi-instantiate.c driver, which
1753 	 * knows which client device id to use for each resource.
1754 	 */
1755 		{"BSG1160", },
1756 		{"BSG2150", },
1757 		{"CSC3551", },
1758 		{"CSC3554", },
1759 		{"CSC3556", },
1760 		{"CSC3557", },
1761 		{"INT33FE", },
1762 		{"INT3515", },
1763 		/* Non-conforming _HID for Cirrus Logic already released */
1764 		{"CLSA0100", },
1765 		{"CLSA0101", },
1766 	/*
1767 	 * Some ACPI devs contain SerialBus resources even though they are not
1768 	 * attached to a serial bus at all.
1769 	 */
1770 		{ACPI_VIDEO_HID, },
1771 		{"MSHW0028", },
1772 	/*
1773 	 * HIDs of device with an UartSerialBusV2 resource for which userspace
1774 	 * expects a regular tty cdev to be created (instead of the in kernel
1775 	 * serdev) and which have a kernel driver which expects a platform_dev
1776 	 * such as the rfkill-gpio driver.
1777 	 */
1778 		{"BCM4752", },
1779 		{"LNV4752", },
1780 		{}
1781 	};
1782 
1783 	if (acpi_is_indirect_io_slave(device))
1784 		return true;
1785 
1786 	/* Macs use device properties in lieu of _CRS resources */
1787 	if (x86_apple_machine &&
1788 	    (fwnode_property_present(&device->fwnode, "spiSclkPeriod") ||
1789 	     fwnode_property_present(&device->fwnode, "i2cAddress") ||
1790 	     fwnode_property_present(&device->fwnode, "baud")))
1791 		return true;
1792 
1793 	if (!acpi_match_device_ids(device, ignore_serial_bus_ids))
1794 		return false;
1795 
1796 	INIT_LIST_HEAD(&resource_list);
1797 	acpi_dev_get_resources(device, &resource_list,
1798 			       acpi_check_serial_bus_slave,
1799 			       &is_serial_bus_slave);
1800 	acpi_dev_free_resource_list(&resource_list);
1801 
1802 	return is_serial_bus_slave;
1803 }
1804 
1805 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1806 			     int type, void (*release)(struct device *))
1807 {
1808 	struct acpi_device *parent = acpi_find_parent_acpi_dev(handle);
1809 
1810 	INIT_LIST_HEAD(&device->pnp.ids);
1811 	device->device_type = type;
1812 	device->handle = handle;
1813 	device->dev.parent = parent ? &parent->dev : NULL;
1814 	device->dev.release = release;
1815 	device->dev.bus = &acpi_bus_type;
1816 	fwnode_init(&device->fwnode, &acpi_device_fwnode_ops);
1817 	acpi_set_device_status(device, ACPI_STA_DEFAULT);
1818 	acpi_device_get_busid(device);
1819 	acpi_set_pnp_ids(handle, &device->pnp, type);
1820 	acpi_init_properties(device);
1821 	acpi_bus_get_flags(device);
1822 	device->flags.match_driver = false;
1823 	device->flags.initialized = true;
1824 	device->flags.enumeration_by_parent =
1825 		acpi_device_enumeration_by_parent(device);
1826 	acpi_device_clear_enumerated(device);
1827 	device_initialize(&device->dev);
1828 	dev_set_uevent_suppress(&device->dev, true);
1829 	acpi_init_coherency(device);
1830 }
1831 
1832 static void acpi_scan_dep_init(struct acpi_device *adev)
1833 {
1834 	struct acpi_dep_data *dep;
1835 
1836 	list_for_each_entry(dep, &acpi_dep_list, node) {
1837 		if (dep->consumer == adev->handle) {
1838 			if (dep->honor_dep)
1839 				adev->flags.honor_deps = 1;
1840 
1841 			if (!dep->met)
1842 				adev->dep_unmet++;
1843 		}
1844 	}
1845 }
1846 
1847 void acpi_device_add_finalize(struct acpi_device *device)
1848 {
1849 	dev_set_uevent_suppress(&device->dev, false);
1850 	kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1851 }
1852 
1853 static void acpi_scan_init_status(struct acpi_device *adev)
1854 {
1855 	if (acpi_bus_get_status(adev))
1856 		acpi_set_device_status(adev, 0);
1857 }
1858 
1859 static int acpi_add_single_object(struct acpi_device **child,
1860 				  acpi_handle handle, int type, bool dep_init)
1861 {
1862 	struct acpi_device *device;
1863 	bool release_dep_lock = false;
1864 	int result;
1865 
1866 	device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1867 	if (!device)
1868 		return -ENOMEM;
1869 
1870 	acpi_init_device_object(device, handle, type, acpi_device_release);
1871 	/*
1872 	 * Getting the status is delayed till here so that we can call
1873 	 * acpi_bus_get_status() and use its quirk handling.  Note that
1874 	 * this must be done before the get power-/wakeup_dev-flags calls.
1875 	 */
1876 	if (type == ACPI_BUS_TYPE_DEVICE || type == ACPI_BUS_TYPE_PROCESSOR) {
1877 		if (dep_init) {
1878 			mutex_lock(&acpi_dep_list_lock);
1879 			/*
1880 			 * Hold the lock until the acpi_tie_acpi_dev() call
1881 			 * below to prevent concurrent acpi_scan_clear_dep()
1882 			 * from deleting a dependency list entry without
1883 			 * updating dep_unmet for the device.
1884 			 */
1885 			release_dep_lock = true;
1886 			acpi_scan_dep_init(device);
1887 		}
1888 		acpi_scan_init_status(device);
1889 	}
1890 
1891 	acpi_bus_get_power_flags(device);
1892 	acpi_bus_get_wakeup_device_flags(device);
1893 
1894 	result = acpi_tie_acpi_dev(device);
1895 
1896 	if (release_dep_lock)
1897 		mutex_unlock(&acpi_dep_list_lock);
1898 
1899 	if (!result)
1900 		result = acpi_device_add(device);
1901 
1902 	if (result) {
1903 		acpi_device_release(&device->dev);
1904 		return result;
1905 	}
1906 
1907 	acpi_power_add_remove_device(device, true);
1908 	acpi_device_add_finalize(device);
1909 
1910 	acpi_handle_debug(handle, "Added as %s, parent %s\n",
1911 			  dev_name(&device->dev), device->dev.parent ?
1912 				dev_name(device->dev.parent) : "(null)");
1913 
1914 	*child = device;
1915 	return 0;
1916 }
1917 
1918 static acpi_status acpi_get_resource_memory(struct acpi_resource *ares,
1919 					    void *context)
1920 {
1921 	struct resource *res = context;
1922 
1923 	if (acpi_dev_resource_memory(ares, res))
1924 		return AE_CTRL_TERMINATE;
1925 
1926 	return AE_OK;
1927 }
1928 
1929 static bool acpi_device_should_be_hidden(acpi_handle handle)
1930 {
1931 	acpi_status status;
1932 	struct resource res;
1933 
1934 	/* Check if it should ignore the UART device */
1935 	if (!(spcr_uart_addr && acpi_has_method(handle, METHOD_NAME__CRS)))
1936 		return false;
1937 
1938 	/*
1939 	 * The UART device described in SPCR table is assumed to have only one
1940 	 * memory resource present. So we only look for the first one here.
1941 	 */
1942 	status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1943 				     acpi_get_resource_memory, &res);
1944 	if (ACPI_FAILURE(status) || res.start != spcr_uart_addr)
1945 		return false;
1946 
1947 	acpi_handle_info(handle, "The UART device @%pa in SPCR table will be hidden\n",
1948 			 &res.start);
1949 
1950 	return true;
1951 }
1952 
1953 bool acpi_device_is_present(const struct acpi_device *adev)
1954 {
1955 	return adev->status.present || adev->status.functional;
1956 }
1957 
1958 bool acpi_device_is_enabled(const struct acpi_device *adev)
1959 {
1960 	return adev->status.enabled;
1961 }
1962 
1963 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1964 				       const char *idstr,
1965 				       const struct acpi_device_id **matchid)
1966 {
1967 	const struct acpi_device_id *devid;
1968 
1969 	if (handler->match)
1970 		return handler->match(idstr, matchid);
1971 
1972 	for (devid = handler->ids; devid->id[0]; devid++)
1973 		if (!strcmp((char *)devid->id, idstr)) {
1974 			if (matchid)
1975 				*matchid = devid;
1976 
1977 			return true;
1978 		}
1979 
1980 	return false;
1981 }
1982 
1983 static struct acpi_scan_handler *acpi_scan_match_handler(const char *idstr,
1984 					const struct acpi_device_id **matchid)
1985 {
1986 	struct acpi_scan_handler *handler;
1987 
1988 	list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1989 		if (acpi_scan_handler_matching(handler, idstr, matchid))
1990 			return handler;
1991 
1992 	return NULL;
1993 }
1994 
1995 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1996 {
1997 	if (!!hotplug->enabled == !!val)
1998 		return;
1999 
2000 	mutex_lock(&acpi_scan_lock);
2001 
2002 	hotplug->enabled = val;
2003 
2004 	mutex_unlock(&acpi_scan_lock);
2005 }
2006 
2007 static void acpi_scan_init_hotplug(struct acpi_device *adev)
2008 {
2009 	struct acpi_hardware_id *hwid;
2010 
2011 	if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
2012 		acpi_dock_add(adev);
2013 		return;
2014 	}
2015 	list_for_each_entry(hwid, &adev->pnp.ids, list) {
2016 		struct acpi_scan_handler *handler;
2017 
2018 		handler = acpi_scan_match_handler(hwid->id, NULL);
2019 		if (handler) {
2020 			adev->flags.hotplug_notify = true;
2021 			break;
2022 		}
2023 	}
2024 }
2025 
2026 static u32 acpi_scan_check_dep(acpi_handle handle)
2027 {
2028 	struct acpi_handle_list dep_devices;
2029 	u32 count;
2030 	int i;
2031 
2032 	/*
2033 	 * Check for _HID here to avoid deferring the enumeration of:
2034 	 * 1. PCI devices.
2035 	 * 2. ACPI nodes describing USB ports.
2036 	 * Still, checking for _HID catches more then just these cases ...
2037 	 */
2038 	if (!acpi_has_method(handle, "_DEP") || !acpi_has_method(handle, "_HID"))
2039 		return 0;
2040 
2041 	if (!acpi_evaluate_reference(handle, "_DEP", NULL, &dep_devices)) {
2042 		acpi_handle_debug(handle, "Failed to evaluate _DEP.\n");
2043 		return 0;
2044 	}
2045 
2046 	for (count = 0, i = 0; i < dep_devices.count; i++) {
2047 		struct acpi_device_info *info;
2048 		struct acpi_dep_data *dep;
2049 		bool skip, honor_dep;
2050 		acpi_status status;
2051 
2052 		status = acpi_get_object_info(dep_devices.handles[i], &info);
2053 		if (ACPI_FAILURE(status)) {
2054 			acpi_handle_debug(handle, "Error reading _DEP device info\n");
2055 			continue;
2056 		}
2057 
2058 		skip = acpi_info_matches_ids(info, acpi_ignore_dep_ids);
2059 		honor_dep = acpi_info_matches_ids(info, acpi_honor_dep_ids);
2060 		kfree(info);
2061 
2062 		if (skip)
2063 			continue;
2064 
2065 		dep = kzalloc(sizeof(*dep), GFP_KERNEL);
2066 		if (!dep)
2067 			continue;
2068 
2069 		count++;
2070 
2071 		dep->supplier = dep_devices.handles[i];
2072 		dep->consumer = handle;
2073 		dep->honor_dep = honor_dep;
2074 
2075 		mutex_lock(&acpi_dep_list_lock);
2076 		list_add_tail(&dep->node , &acpi_dep_list);
2077 		mutex_unlock(&acpi_dep_list_lock);
2078 	}
2079 
2080 	acpi_handle_list_free(&dep_devices);
2081 	return count;
2082 }
2083 
2084 static acpi_status acpi_scan_check_crs_csi2_cb(acpi_handle handle, u32 a, void *b, void **c)
2085 {
2086 	acpi_mipi_check_crs_csi2(handle);
2087 	return AE_OK;
2088 }
2089 
2090 static acpi_status acpi_bus_check_add(acpi_handle handle, bool first_pass,
2091 				      struct acpi_device **adev_p)
2092 {
2093 	struct acpi_device *device = acpi_fetch_acpi_dev(handle);
2094 	acpi_object_type acpi_type;
2095 	int type;
2096 
2097 	if (device)
2098 		goto out;
2099 
2100 	if (ACPI_FAILURE(acpi_get_type(handle, &acpi_type)))
2101 		return AE_OK;
2102 
2103 	switch (acpi_type) {
2104 	case ACPI_TYPE_DEVICE:
2105 		if (acpi_device_should_be_hidden(handle))
2106 			return AE_OK;
2107 
2108 		if (first_pass) {
2109 			acpi_mipi_check_crs_csi2(handle);
2110 
2111 			/* Bail out if there are dependencies. */
2112 			if (acpi_scan_check_dep(handle) > 0) {
2113 				/*
2114 				 * The entire CSI-2 connection graph needs to be
2115 				 * extracted before any drivers or scan handlers
2116 				 * are bound to struct device objects, so scan
2117 				 * _CRS CSI-2 resource descriptors for all
2118 				 * devices below the current handle.
2119 				 */
2120 				acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
2121 						    ACPI_UINT32_MAX,
2122 						    acpi_scan_check_crs_csi2_cb,
2123 						    NULL, NULL, NULL);
2124 				return AE_CTRL_DEPTH;
2125 			}
2126 		}
2127 
2128 		fallthrough;
2129 	case ACPI_TYPE_ANY:	/* for ACPI_ROOT_OBJECT */
2130 		type = ACPI_BUS_TYPE_DEVICE;
2131 		break;
2132 
2133 	case ACPI_TYPE_PROCESSOR:
2134 		type = ACPI_BUS_TYPE_PROCESSOR;
2135 		break;
2136 
2137 	case ACPI_TYPE_THERMAL:
2138 		type = ACPI_BUS_TYPE_THERMAL;
2139 		break;
2140 
2141 	case ACPI_TYPE_POWER:
2142 		acpi_add_power_resource(handle);
2143 		fallthrough;
2144 	default:
2145 		return AE_OK;
2146 	}
2147 
2148 	/*
2149 	 * If first_pass is true at this point, the device has no dependencies,
2150 	 * or the creation of the device object would have been postponed above.
2151 	 */
2152 	acpi_add_single_object(&device, handle, type, !first_pass);
2153 	if (!device)
2154 		return AE_CTRL_DEPTH;
2155 
2156 	acpi_scan_init_hotplug(device);
2157 
2158 out:
2159 	if (!*adev_p)
2160 		*adev_p = device;
2161 
2162 	return AE_OK;
2163 }
2164 
2165 static acpi_status acpi_bus_check_add_1(acpi_handle handle, u32 lvl_not_used,
2166 					void *not_used, void **ret_p)
2167 {
2168 	return acpi_bus_check_add(handle, true, (struct acpi_device **)ret_p);
2169 }
2170 
2171 static acpi_status acpi_bus_check_add_2(acpi_handle handle, u32 lvl_not_used,
2172 					void *not_used, void **ret_p)
2173 {
2174 	return acpi_bus_check_add(handle, false, (struct acpi_device **)ret_p);
2175 }
2176 
2177 static void acpi_default_enumeration(struct acpi_device *device)
2178 {
2179 	/*
2180 	 * Do not enumerate devices with enumeration_by_parent flag set as
2181 	 * they will be enumerated by their respective parents.
2182 	 */
2183 	if (!device->flags.enumeration_by_parent) {
2184 		acpi_create_platform_device(device, NULL);
2185 		acpi_device_set_enumerated(device);
2186 	} else {
2187 		blocking_notifier_call_chain(&acpi_reconfig_chain,
2188 					     ACPI_RECONFIG_DEVICE_ADD, device);
2189 	}
2190 }
2191 
2192 static const struct acpi_device_id generic_device_ids[] = {
2193 	{ACPI_DT_NAMESPACE_HID, },
2194 	{"", },
2195 };
2196 
2197 static int acpi_generic_device_attach(struct acpi_device *adev,
2198 				      const struct acpi_device_id *not_used)
2199 {
2200 	/*
2201 	 * Since ACPI_DT_NAMESPACE_HID is the only ID handled here, the test
2202 	 * below can be unconditional.
2203 	 */
2204 	if (adev->data.of_compatible)
2205 		acpi_default_enumeration(adev);
2206 
2207 	return 1;
2208 }
2209 
2210 static struct acpi_scan_handler generic_device_handler = {
2211 	.ids = generic_device_ids,
2212 	.attach = acpi_generic_device_attach,
2213 };
2214 
2215 static int acpi_scan_attach_handler(struct acpi_device *device)
2216 {
2217 	struct acpi_hardware_id *hwid;
2218 	int ret = 0;
2219 
2220 	list_for_each_entry(hwid, &device->pnp.ids, list) {
2221 		const struct acpi_device_id *devid;
2222 		struct acpi_scan_handler *handler;
2223 
2224 		handler = acpi_scan_match_handler(hwid->id, &devid);
2225 		if (handler) {
2226 			if (!handler->attach) {
2227 				device->pnp.type.platform_id = 0;
2228 				continue;
2229 			}
2230 			device->handler = handler;
2231 			ret = handler->attach(device, devid);
2232 			if (ret > 0)
2233 				break;
2234 
2235 			device->handler = NULL;
2236 			if (ret < 0)
2237 				break;
2238 		}
2239 	}
2240 
2241 	return ret;
2242 }
2243 
2244 static int acpi_bus_attach(struct acpi_device *device, void *first_pass)
2245 {
2246 	bool skip = !first_pass && device->flags.visited;
2247 	acpi_handle ejd;
2248 	int ret;
2249 
2250 	if (skip)
2251 		goto ok;
2252 
2253 	if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
2254 		register_dock_dependent_device(device, ejd);
2255 
2256 	acpi_bus_get_status(device);
2257 	/* Skip devices that are not ready for enumeration (e.g. not present) */
2258 	if (!acpi_dev_ready_for_enumeration(device)) {
2259 		device->flags.initialized = false;
2260 		acpi_device_clear_enumerated(device);
2261 		device->flags.power_manageable = 0;
2262 		return 0;
2263 	}
2264 	if (device->handler)
2265 		goto ok;
2266 
2267 	if (!device->flags.initialized) {
2268 		device->flags.power_manageable =
2269 			device->power.states[ACPI_STATE_D0].flags.valid;
2270 		if (acpi_bus_init_power(device))
2271 			device->flags.power_manageable = 0;
2272 
2273 		device->flags.initialized = true;
2274 	} else if (device->flags.visited) {
2275 		goto ok;
2276 	}
2277 
2278 	ret = acpi_scan_attach_handler(device);
2279 	if (ret < 0)
2280 		return 0;
2281 
2282 	device->flags.match_driver = true;
2283 	if (ret > 0 && !device->flags.enumeration_by_parent) {
2284 		acpi_device_set_enumerated(device);
2285 		goto ok;
2286 	}
2287 
2288 	ret = device_attach(&device->dev);
2289 	if (ret < 0)
2290 		return 0;
2291 
2292 	if (device->pnp.type.platform_id || device->flags.enumeration_by_parent)
2293 		acpi_default_enumeration(device);
2294 	else
2295 		acpi_device_set_enumerated(device);
2296 
2297 ok:
2298 	acpi_dev_for_each_child(device, acpi_bus_attach, first_pass);
2299 
2300 	if (!skip && device->handler && device->handler->hotplug.notify_online)
2301 		device->handler->hotplug.notify_online(device);
2302 
2303 	return 0;
2304 }
2305 
2306 static int acpi_dev_get_next_consumer_dev_cb(struct acpi_dep_data *dep, void *data)
2307 {
2308 	struct acpi_device **adev_p = data;
2309 	struct acpi_device *adev = *adev_p;
2310 
2311 	/*
2312 	 * If we're passed a 'previous' consumer device then we need to skip
2313 	 * any consumers until we meet the previous one, and then NULL @data
2314 	 * so the next one can be returned.
2315 	 */
2316 	if (adev) {
2317 		if (dep->consumer == adev->handle)
2318 			*adev_p = NULL;
2319 
2320 		return 0;
2321 	}
2322 
2323 	adev = acpi_get_acpi_dev(dep->consumer);
2324 	if (adev) {
2325 		*(struct acpi_device **)data = adev;
2326 		return 1;
2327 	}
2328 	/* Continue parsing if the device object is not present. */
2329 	return 0;
2330 }
2331 
2332 struct acpi_scan_clear_dep_work {
2333 	struct work_struct work;
2334 	struct acpi_device *adev;
2335 };
2336 
2337 static void acpi_scan_clear_dep_fn(struct work_struct *work)
2338 {
2339 	struct acpi_scan_clear_dep_work *cdw;
2340 
2341 	cdw = container_of(work, struct acpi_scan_clear_dep_work, work);
2342 
2343 	acpi_scan_lock_acquire();
2344 	acpi_bus_attach(cdw->adev, (void *)true);
2345 	acpi_scan_lock_release();
2346 
2347 	acpi_dev_put(cdw->adev);
2348 	kfree(cdw);
2349 }
2350 
2351 static bool acpi_scan_clear_dep_queue(struct acpi_device *adev)
2352 {
2353 	struct acpi_scan_clear_dep_work *cdw;
2354 
2355 	if (adev->dep_unmet)
2356 		return false;
2357 
2358 	cdw = kmalloc(sizeof(*cdw), GFP_KERNEL);
2359 	if (!cdw)
2360 		return false;
2361 
2362 	cdw->adev = adev;
2363 	INIT_WORK(&cdw->work, acpi_scan_clear_dep_fn);
2364 	/*
2365 	 * Since the work function may block on the lock until the entire
2366 	 * initial enumeration of devices is complete, put it into the unbound
2367 	 * workqueue.
2368 	 */
2369 	queue_work(system_unbound_wq, &cdw->work);
2370 
2371 	return true;
2372 }
2373 
2374 static void acpi_scan_delete_dep_data(struct acpi_dep_data *dep)
2375 {
2376 	list_del(&dep->node);
2377 	kfree(dep);
2378 }
2379 
2380 static int acpi_scan_clear_dep(struct acpi_dep_data *dep, void *data)
2381 {
2382 	struct acpi_device *adev = acpi_get_acpi_dev(dep->consumer);
2383 
2384 	if (adev) {
2385 		adev->dep_unmet--;
2386 		if (!acpi_scan_clear_dep_queue(adev))
2387 			acpi_dev_put(adev);
2388 	}
2389 
2390 	if (dep->free_when_met)
2391 		acpi_scan_delete_dep_data(dep);
2392 	else
2393 		dep->met = true;
2394 
2395 	return 0;
2396 }
2397 
2398 /**
2399  * acpi_walk_dep_device_list - Apply a callback to every entry in acpi_dep_list
2400  * @handle:	The ACPI handle of the supplier device
2401  * @callback:	Pointer to the callback function to apply
2402  * @data:	Pointer to some data to pass to the callback
2403  *
2404  * The return value of the callback determines this function's behaviour. If 0
2405  * is returned we continue to iterate over acpi_dep_list. If a positive value
2406  * is returned then the loop is broken but this function returns 0. If a
2407  * negative value is returned by the callback then the loop is broken and that
2408  * value is returned as the final error.
2409  */
2410 static int acpi_walk_dep_device_list(acpi_handle handle,
2411 				int (*callback)(struct acpi_dep_data *, void *),
2412 				void *data)
2413 {
2414 	struct acpi_dep_data *dep, *tmp;
2415 	int ret = 0;
2416 
2417 	mutex_lock(&acpi_dep_list_lock);
2418 	list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
2419 		if (dep->supplier == handle) {
2420 			ret = callback(dep, data);
2421 			if (ret)
2422 				break;
2423 		}
2424 	}
2425 	mutex_unlock(&acpi_dep_list_lock);
2426 
2427 	return ret > 0 ? 0 : ret;
2428 }
2429 
2430 /**
2431  * acpi_dev_clear_dependencies - Inform consumers that the device is now active
2432  * @supplier: Pointer to the supplier &struct acpi_device
2433  *
2434  * Clear dependencies on the given device.
2435  */
2436 void acpi_dev_clear_dependencies(struct acpi_device *supplier)
2437 {
2438 	acpi_walk_dep_device_list(supplier->handle, acpi_scan_clear_dep, NULL);
2439 }
2440 EXPORT_SYMBOL_GPL(acpi_dev_clear_dependencies);
2441 
2442 /**
2443  * acpi_dev_ready_for_enumeration - Check if the ACPI device is ready for enumeration
2444  * @device: Pointer to the &struct acpi_device to check
2445  *
2446  * Check if the device is present and has no unmet dependencies.
2447  *
2448  * Return true if the device is ready for enumeratino. Otherwise, return false.
2449  */
2450 bool acpi_dev_ready_for_enumeration(const struct acpi_device *device)
2451 {
2452 	if (device->flags.honor_deps && device->dep_unmet)
2453 		return false;
2454 
2455 	return acpi_device_is_present(device);
2456 }
2457 EXPORT_SYMBOL_GPL(acpi_dev_ready_for_enumeration);
2458 
2459 /**
2460  * acpi_dev_get_next_consumer_dev - Return the next adev dependent on @supplier
2461  * @supplier: Pointer to the dependee device
2462  * @start: Pointer to the current dependent device
2463  *
2464  * Returns the next &struct acpi_device which declares itself dependent on
2465  * @supplier via the _DEP buffer, parsed from the acpi_dep_list.
2466  *
2467  * If the returned adev is not passed as @start to this function, the caller is
2468  * responsible for putting the reference to adev when it is no longer needed.
2469  */
2470 struct acpi_device *acpi_dev_get_next_consumer_dev(struct acpi_device *supplier,
2471 						   struct acpi_device *start)
2472 {
2473 	struct acpi_device *adev = start;
2474 
2475 	acpi_walk_dep_device_list(supplier->handle,
2476 				  acpi_dev_get_next_consumer_dev_cb, &adev);
2477 
2478 	acpi_dev_put(start);
2479 
2480 	if (adev == start)
2481 		return NULL;
2482 
2483 	return adev;
2484 }
2485 EXPORT_SYMBOL_GPL(acpi_dev_get_next_consumer_dev);
2486 
2487 static void acpi_scan_postponed_branch(acpi_handle handle)
2488 {
2489 	struct acpi_device *adev = NULL;
2490 
2491 	if (ACPI_FAILURE(acpi_bus_check_add(handle, false, &adev)))
2492 		return;
2493 
2494 	acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2495 			    acpi_bus_check_add_2, NULL, NULL, (void **)&adev);
2496 
2497 	/*
2498 	 * Populate the ACPI _CRS CSI-2 software nodes for the ACPI devices that
2499 	 * have been added above.
2500 	 */
2501 	acpi_mipi_init_crs_csi2_swnodes();
2502 
2503 	acpi_bus_attach(adev, NULL);
2504 }
2505 
2506 static void acpi_scan_postponed(void)
2507 {
2508 	struct acpi_dep_data *dep, *tmp;
2509 
2510 	mutex_lock(&acpi_dep_list_lock);
2511 
2512 	list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
2513 		acpi_handle handle = dep->consumer;
2514 
2515 		/*
2516 		 * In case there are multiple acpi_dep_list entries with the
2517 		 * same consumer, skip the current entry if the consumer device
2518 		 * object corresponding to it is present already.
2519 		 */
2520 		if (!acpi_fetch_acpi_dev(handle)) {
2521 			/*
2522 			 * Even though the lock is released here, tmp is
2523 			 * guaranteed to be valid, because none of the list
2524 			 * entries following dep is marked as "free when met"
2525 			 * and so they cannot be deleted.
2526 			 */
2527 			mutex_unlock(&acpi_dep_list_lock);
2528 
2529 			acpi_scan_postponed_branch(handle);
2530 
2531 			mutex_lock(&acpi_dep_list_lock);
2532 		}
2533 
2534 		if (dep->met)
2535 			acpi_scan_delete_dep_data(dep);
2536 		else
2537 			dep->free_when_met = true;
2538 	}
2539 
2540 	mutex_unlock(&acpi_dep_list_lock);
2541 }
2542 
2543 /**
2544  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
2545  * @handle: Root of the namespace scope to scan.
2546  *
2547  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
2548  * found devices.
2549  *
2550  * If no devices were found, -ENODEV is returned, but it does not mean that
2551  * there has been a real error.  There just have been no suitable ACPI objects
2552  * in the table trunk from which the kernel could create a device and add an
2553  * appropriate driver.
2554  *
2555  * Must be called under acpi_scan_lock.
2556  */
2557 int acpi_bus_scan(acpi_handle handle)
2558 {
2559 	struct acpi_device *device = NULL;
2560 
2561 	/* Pass 1: Avoid enumerating devices with missing dependencies. */
2562 
2563 	if (ACPI_SUCCESS(acpi_bus_check_add(handle, true, &device)))
2564 		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2565 				    acpi_bus_check_add_1, NULL, NULL,
2566 				    (void **)&device);
2567 
2568 	if (!device)
2569 		return -ENODEV;
2570 
2571 	/*
2572 	 * Set up ACPI _CRS CSI-2 software nodes using information extracted
2573 	 * from the _CRS CSI-2 resource descriptors during the ACPI namespace
2574 	 * walk above and MIPI DisCo for Imaging device properties.
2575 	 */
2576 	acpi_mipi_scan_crs_csi2();
2577 	acpi_mipi_init_crs_csi2_swnodes();
2578 
2579 	acpi_bus_attach(device, (void *)true);
2580 
2581 	/* Pass 2: Enumerate all of the remaining devices. */
2582 
2583 	acpi_scan_postponed();
2584 
2585 	acpi_mipi_crs_csi2_cleanup();
2586 
2587 	return 0;
2588 }
2589 EXPORT_SYMBOL(acpi_bus_scan);
2590 
2591 /**
2592  * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
2593  * @adev: Root of the ACPI namespace scope to walk.
2594  *
2595  * Must be called under acpi_scan_lock.
2596  */
2597 void acpi_bus_trim(struct acpi_device *adev)
2598 {
2599 	acpi_scan_check_and_detach(adev, NULL);
2600 }
2601 EXPORT_SYMBOL_GPL(acpi_bus_trim);
2602 
2603 int acpi_bus_register_early_device(int type)
2604 {
2605 	struct acpi_device *device = NULL;
2606 	int result;
2607 
2608 	result = acpi_add_single_object(&device, NULL, type, false);
2609 	if (result)
2610 		return result;
2611 
2612 	device->flags.match_driver = true;
2613 	return device_attach(&device->dev);
2614 }
2615 EXPORT_SYMBOL_GPL(acpi_bus_register_early_device);
2616 
2617 static void acpi_bus_scan_fixed(void)
2618 {
2619 	if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2620 		struct acpi_device *adev = NULL;
2621 
2622 		acpi_add_single_object(&adev, NULL, ACPI_BUS_TYPE_POWER_BUTTON,
2623 				       false);
2624 		if (adev) {
2625 			adev->flags.match_driver = true;
2626 			if (device_attach(&adev->dev) >= 0)
2627 				device_init_wakeup(&adev->dev, true);
2628 			else
2629 				dev_dbg(&adev->dev, "No driver\n");
2630 		}
2631 	}
2632 
2633 	if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2634 		struct acpi_device *adev = NULL;
2635 
2636 		acpi_add_single_object(&adev, NULL, ACPI_BUS_TYPE_SLEEP_BUTTON,
2637 				       false);
2638 		if (adev) {
2639 			adev->flags.match_driver = true;
2640 			if (device_attach(&adev->dev) < 0)
2641 				dev_dbg(&adev->dev, "No driver\n");
2642 		}
2643 	}
2644 }
2645 
2646 static void __init acpi_get_spcr_uart_addr(void)
2647 {
2648 	acpi_status status;
2649 	struct acpi_table_spcr *spcr_ptr;
2650 
2651 	status = acpi_get_table(ACPI_SIG_SPCR, 0,
2652 				(struct acpi_table_header **)&spcr_ptr);
2653 	if (ACPI_FAILURE(status)) {
2654 		pr_warn("STAO table present, but SPCR is missing\n");
2655 		return;
2656 	}
2657 
2658 	spcr_uart_addr = spcr_ptr->serial_port.address;
2659 	acpi_put_table((struct acpi_table_header *)spcr_ptr);
2660 }
2661 
2662 static bool acpi_scan_initialized;
2663 
2664 void __init acpi_scan_init(void)
2665 {
2666 	acpi_status status;
2667 	struct acpi_table_stao *stao_ptr;
2668 
2669 	acpi_pci_root_init();
2670 	acpi_pci_link_init();
2671 	acpi_processor_init();
2672 	acpi_platform_init();
2673 	acpi_lpss_init();
2674 	acpi_apd_init();
2675 	acpi_cmos_rtc_init();
2676 	acpi_container_init();
2677 	acpi_memory_hotplug_init();
2678 	acpi_watchdog_init();
2679 	acpi_pnp_init();
2680 	acpi_int340x_thermal_init();
2681 	acpi_init_lpit();
2682 
2683 	acpi_scan_add_handler(&generic_device_handler);
2684 
2685 	/*
2686 	 * If there is STAO table, check whether it needs to ignore the UART
2687 	 * device in SPCR table.
2688 	 */
2689 	status = acpi_get_table(ACPI_SIG_STAO, 0,
2690 				(struct acpi_table_header **)&stao_ptr);
2691 	if (ACPI_SUCCESS(status)) {
2692 		if (stao_ptr->header.length > sizeof(struct acpi_table_stao))
2693 			pr_info("STAO Name List not yet supported.\n");
2694 
2695 		if (stao_ptr->ignore_uart)
2696 			acpi_get_spcr_uart_addr();
2697 
2698 		acpi_put_table((struct acpi_table_header *)stao_ptr);
2699 	}
2700 
2701 	acpi_gpe_apply_masked_gpes();
2702 	acpi_update_all_gpes();
2703 
2704 	/*
2705 	 * Although we call __add_memory() that is documented to require the
2706 	 * device_hotplug_lock, it is not necessary here because this is an
2707 	 * early code when userspace or any other code path cannot trigger
2708 	 * hotplug/hotunplug operations.
2709 	 */
2710 	mutex_lock(&acpi_scan_lock);
2711 	/*
2712 	 * Enumerate devices in the ACPI namespace.
2713 	 */
2714 	if (acpi_bus_scan(ACPI_ROOT_OBJECT))
2715 		goto unlock;
2716 
2717 	acpi_root = acpi_fetch_acpi_dev(ACPI_ROOT_OBJECT);
2718 	if (!acpi_root)
2719 		goto unlock;
2720 
2721 	/* Fixed feature devices do not exist on HW-reduced platform */
2722 	if (!acpi_gbl_reduced_hardware)
2723 		acpi_bus_scan_fixed();
2724 
2725 	acpi_turn_off_unused_power_resources();
2726 
2727 	acpi_scan_initialized = true;
2728 
2729 unlock:
2730 	mutex_unlock(&acpi_scan_lock);
2731 }
2732 
2733 static struct acpi_probe_entry *ape;
2734 static int acpi_probe_count;
2735 static DEFINE_MUTEX(acpi_probe_mutex);
2736 
2737 static int __init acpi_match_madt(union acpi_subtable_headers *header,
2738 				  const unsigned long end)
2739 {
2740 	if (!ape->subtable_valid || ape->subtable_valid(&header->common, ape))
2741 		if (!ape->probe_subtbl(header, end))
2742 			acpi_probe_count++;
2743 
2744 	return 0;
2745 }
2746 
2747 int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr)
2748 {
2749 	int count = 0;
2750 
2751 	if (acpi_disabled)
2752 		return 0;
2753 
2754 	mutex_lock(&acpi_probe_mutex);
2755 	for (ape = ap_head; nr; ape++, nr--) {
2756 		if (ACPI_COMPARE_NAMESEG(ACPI_SIG_MADT, ape->id)) {
2757 			acpi_probe_count = 0;
2758 			acpi_table_parse_madt(ape->type, acpi_match_madt, 0);
2759 			count += acpi_probe_count;
2760 		} else {
2761 			int res;
2762 			res = acpi_table_parse(ape->id, ape->probe_table);
2763 			if (!res)
2764 				count++;
2765 		}
2766 	}
2767 	mutex_unlock(&acpi_probe_mutex);
2768 
2769 	return count;
2770 }
2771 
2772 static void acpi_table_events_fn(struct work_struct *work)
2773 {
2774 	acpi_scan_lock_acquire();
2775 	acpi_bus_scan(ACPI_ROOT_OBJECT);
2776 	acpi_scan_lock_release();
2777 
2778 	kfree(work);
2779 }
2780 
2781 void acpi_scan_table_notify(void)
2782 {
2783 	struct work_struct *work;
2784 
2785 	if (!acpi_scan_initialized)
2786 		return;
2787 
2788 	work = kmalloc(sizeof(*work), GFP_KERNEL);
2789 	if (!work)
2790 		return;
2791 
2792 	INIT_WORK(work, acpi_table_events_fn);
2793 	schedule_work(work);
2794 }
2795 
2796 int acpi_reconfig_notifier_register(struct notifier_block *nb)
2797 {
2798 	return blocking_notifier_chain_register(&acpi_reconfig_chain, nb);
2799 }
2800 EXPORT_SYMBOL(acpi_reconfig_notifier_register);
2801 
2802 int acpi_reconfig_notifier_unregister(struct notifier_block *nb)
2803 {
2804 	return blocking_notifier_chain_unregister(&acpi_reconfig_chain, nb);
2805 }
2806 EXPORT_SYMBOL(acpi_reconfig_notifier_unregister);
2807