xref: /linux/drivers/acpi/scan.c (revision 7255fcc80d4b525cc10cfaaf7f485830d4ed2000)
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 				int (*notify)(struct acpi_device *, u32),
77 				void (*uevent)(struct acpi_device *, u32))
78 {
79 	acpi_lock_hp_context();
80 	hp->notify = notify;
81 	hp->uevent = uevent;
82 	acpi_set_hp_context(adev, hp);
83 	acpi_unlock_hp_context();
84 }
85 EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
86 
87 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
88 {
89 	if (!handler)
90 		return -EINVAL;
91 
92 	list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
93 	return 0;
94 }
95 
96 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
97 				       const char *hotplug_profile_name)
98 {
99 	int error;
100 
101 	error = acpi_scan_add_handler(handler);
102 	if (error)
103 		return error;
104 
105 	acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
106 	return 0;
107 }
108 
109 bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
110 {
111 	struct acpi_device_physical_node *pn;
112 	bool offline = true;
113 	char *envp[] = { "EVENT=offline", NULL };
114 
115 	/*
116 	 * acpi_container_offline() calls this for all of the container's
117 	 * children under the container's physical_node_lock lock.
118 	 */
119 	mutex_lock_nested(&adev->physical_node_lock, SINGLE_DEPTH_NESTING);
120 
121 	list_for_each_entry(pn, &adev->physical_node_list, node)
122 		if (device_supports_offline(pn->dev) && !pn->dev->offline) {
123 			if (uevent)
124 				kobject_uevent_env(&pn->dev->kobj, KOBJ_CHANGE, envp);
125 
126 			offline = false;
127 			break;
128 		}
129 
130 	mutex_unlock(&adev->physical_node_lock);
131 	return offline;
132 }
133 
134 static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
135 				    void **ret_p)
136 {
137 	struct acpi_device *device = acpi_fetch_acpi_dev(handle);
138 	struct acpi_device_physical_node *pn;
139 	bool second_pass = (bool)data;
140 	acpi_status status = AE_OK;
141 
142 	if (!device)
143 		return AE_OK;
144 
145 	if (device->handler && !device->handler->hotplug.enabled) {
146 		*ret_p = &device->dev;
147 		return AE_SUPPORT;
148 	}
149 
150 	mutex_lock(&device->physical_node_lock);
151 
152 	list_for_each_entry(pn, &device->physical_node_list, node) {
153 		int ret;
154 
155 		if (second_pass) {
156 			/* Skip devices offlined by the first pass. */
157 			if (pn->put_online)
158 				continue;
159 		} else {
160 			pn->put_online = false;
161 		}
162 		ret = device_offline(pn->dev);
163 		if (ret >= 0) {
164 			pn->put_online = !ret;
165 		} else {
166 			*ret_p = pn->dev;
167 			if (second_pass) {
168 				status = AE_ERROR;
169 				break;
170 			}
171 		}
172 	}
173 
174 	mutex_unlock(&device->physical_node_lock);
175 
176 	return status;
177 }
178 
179 static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
180 				   void **ret_p)
181 {
182 	struct acpi_device *device = acpi_fetch_acpi_dev(handle);
183 	struct acpi_device_physical_node *pn;
184 
185 	if (!device)
186 		return AE_OK;
187 
188 	mutex_lock(&device->physical_node_lock);
189 
190 	list_for_each_entry(pn, &device->physical_node_list, node)
191 		if (pn->put_online) {
192 			device_online(pn->dev);
193 			pn->put_online = false;
194 		}
195 
196 	mutex_unlock(&device->physical_node_lock);
197 
198 	return AE_OK;
199 }
200 
201 static int acpi_scan_try_to_offline(struct acpi_device *device)
202 {
203 	acpi_handle handle = device->handle;
204 	struct device *errdev = NULL;
205 	acpi_status status;
206 
207 	/*
208 	 * Carry out two passes here and ignore errors in the first pass,
209 	 * because if the devices in question are memory blocks and
210 	 * CONFIG_MEMCG is set, one of the blocks may hold data structures
211 	 * that the other blocks depend on, but it is not known in advance which
212 	 * block holds them.
213 	 *
214 	 * If the first pass is successful, the second one isn't needed, though.
215 	 */
216 	status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
217 				     NULL, acpi_bus_offline, (void *)false,
218 				     (void **)&errdev);
219 	if (status == AE_SUPPORT) {
220 		dev_warn(errdev, "Offline disabled.\n");
221 		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
222 				    acpi_bus_online, NULL, NULL, NULL);
223 		return -EPERM;
224 	}
225 	acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
226 	if (errdev) {
227 		errdev = NULL;
228 		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
229 				    NULL, acpi_bus_offline, (void *)true,
230 				    (void **)&errdev);
231 		if (!errdev)
232 			acpi_bus_offline(handle, 0, (void *)true,
233 					 (void **)&errdev);
234 
235 		if (errdev) {
236 			dev_warn(errdev, "Offline failed.\n");
237 			acpi_bus_online(handle, 0, NULL, NULL);
238 			acpi_walk_namespace(ACPI_TYPE_ANY, handle,
239 					    ACPI_UINT32_MAX, acpi_bus_online,
240 					    NULL, NULL, NULL);
241 			return -EBUSY;
242 		}
243 	}
244 	return 0;
245 }
246 
247 static int acpi_scan_check_and_detach(struct acpi_device *adev, void *check)
248 {
249 	struct acpi_scan_handler *handler = adev->handler;
250 
251 	acpi_dev_for_each_child_reverse(adev, acpi_scan_check_and_detach, check);
252 
253 	if (check) {
254 		acpi_bus_get_status(adev);
255 		/*
256 		 * Skip devices that are still there and take the enabled
257 		 * flag into account.
258 		 */
259 		if (acpi_device_is_enabled(adev))
260 			return 0;
261 
262 		/* Skip device that have not been enumerated. */
263 		if (!acpi_device_enumerated(adev)) {
264 			dev_dbg(&adev->dev, "Still not enumerated\n");
265 			return 0;
266 		}
267 	}
268 
269 	adev->flags.match_driver = false;
270 	if (handler) {
271 		if (handler->detach)
272 			handler->detach(adev);
273 
274 		adev->handler = NULL;
275 	} else {
276 		device_release_driver(&adev->dev);
277 	}
278 	/*
279 	 * Most likely, the device is going away, so put it into D3cold before
280 	 * that.
281 	 */
282 	acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
283 	adev->flags.initialized = false;
284 	acpi_device_clear_enumerated(adev);
285 
286 	return 0;
287 }
288 
289 static void acpi_scan_check_subtree(struct acpi_device *adev)
290 {
291 	acpi_scan_check_and_detach(adev, (void *)true);
292 }
293 
294 static int acpi_scan_hot_remove(struct acpi_device *device)
295 {
296 	acpi_handle handle = device->handle;
297 	unsigned long long sta;
298 	acpi_status status;
299 
300 	if (device->handler && device->handler->hotplug.demand_offline) {
301 		if (!acpi_scan_is_offline(device, true))
302 			return -EBUSY;
303 	} else {
304 		int error = acpi_scan_try_to_offline(device);
305 		if (error)
306 			return error;
307 	}
308 
309 	acpi_handle_debug(handle, "Ejecting\n");
310 
311 	acpi_bus_trim(device);
312 
313 	acpi_evaluate_lck(handle, 0);
314 	/*
315 	 * TBD: _EJD support.
316 	 */
317 	status = acpi_evaluate_ej0(handle);
318 	if (status == AE_NOT_FOUND)
319 		return -ENODEV;
320 	else if (ACPI_FAILURE(status))
321 		return -EIO;
322 
323 	/*
324 	 * Verify if eject was indeed successful.  If not, log an error
325 	 * message.  No need to call _OST since _EJ0 call was made OK.
326 	 */
327 	status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
328 	if (ACPI_FAILURE(status)) {
329 		acpi_handle_warn(handle,
330 			"Status check after eject failed (0x%x)\n", status);
331 	} else if (sta & ACPI_STA_DEVICE_ENABLED) {
332 		acpi_handle_warn(handle,
333 			"Eject incomplete - status 0x%llx\n", sta);
334 	}
335 
336 	return 0;
337 }
338 
339 static int acpi_scan_rescan_bus(struct acpi_device *adev)
340 {
341 	struct acpi_scan_handler *handler = adev->handler;
342 	int ret;
343 
344 	if (handler && handler->hotplug.scan_dependent)
345 		ret = handler->hotplug.scan_dependent(adev);
346 	else
347 		ret = acpi_bus_scan(adev->handle);
348 
349 	if (ret)
350 		dev_info(&adev->dev, "Namespace scan failure\n");
351 
352 	return ret;
353 }
354 
355 static int acpi_scan_device_check(struct acpi_device *adev)
356 {
357 	struct acpi_device *parent;
358 
359 	acpi_scan_check_subtree(adev);
360 
361 	if (!acpi_device_is_present(adev))
362 		return 0;
363 
364 	/*
365 	 * This function is only called for device objects for which matching
366 	 * scan handlers exist.  The only situation in which the scan handler
367 	 * is not attached to this device object yet is when the device has
368 	 * just appeared (either it wasn't present at all before or it was
369 	 * removed and then added again).
370 	 */
371 	if (adev->handler) {
372 		dev_dbg(&adev->dev, "Already enumerated\n");
373 		return 0;
374 	}
375 
376 	parent = acpi_dev_parent(adev);
377 	if (!parent)
378 		parent = adev;
379 
380 	return acpi_scan_rescan_bus(parent);
381 }
382 
383 static int acpi_scan_bus_check(struct acpi_device *adev)
384 {
385 	acpi_scan_check_subtree(adev);
386 
387 	return acpi_scan_rescan_bus(adev);
388 }
389 
390 static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type)
391 {
392 	switch (type) {
393 	case ACPI_NOTIFY_BUS_CHECK:
394 		return acpi_scan_bus_check(adev);
395 	case ACPI_NOTIFY_DEVICE_CHECK:
396 		return acpi_scan_device_check(adev);
397 	case ACPI_NOTIFY_EJECT_REQUEST:
398 	case ACPI_OST_EC_OSPM_EJECT:
399 		if (adev->handler && !adev->handler->hotplug.enabled) {
400 			dev_info(&adev->dev, "Eject disabled\n");
401 			return -EPERM;
402 		}
403 		acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST,
404 				  ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
405 		return acpi_scan_hot_remove(adev);
406 	}
407 	return -EINVAL;
408 }
409 
410 void acpi_device_hotplug(struct acpi_device *adev, u32 src)
411 {
412 	u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
413 	int error = -ENODEV;
414 
415 	lock_device_hotplug();
416 	mutex_lock(&acpi_scan_lock);
417 
418 	/*
419 	 * The device object's ACPI handle cannot become invalid as long as we
420 	 * are holding acpi_scan_lock, but it might have become invalid before
421 	 * that lock was acquired.
422 	 */
423 	if (adev->handle == INVALID_ACPI_HANDLE)
424 		goto err_out;
425 
426 	if (adev->flags.is_dock_station) {
427 		error = dock_notify(adev, src);
428 	} else if (adev->flags.hotplug_notify) {
429 		error = acpi_generic_hotplug_event(adev, src);
430 	} else {
431 		int (*notify)(struct acpi_device *, u32);
432 
433 		acpi_lock_hp_context();
434 		notify = adev->hp ? adev->hp->notify : NULL;
435 		acpi_unlock_hp_context();
436 		/*
437 		 * There may be additional notify handlers for device objects
438 		 * without the .event() callback, so ignore them here.
439 		 */
440 		if (notify)
441 			error = notify(adev, src);
442 		else
443 			goto out;
444 	}
445 	switch (error) {
446 	case 0:
447 		ost_code = ACPI_OST_SC_SUCCESS;
448 		break;
449 	case -EPERM:
450 		ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
451 		break;
452 	case -EBUSY:
453 		ost_code = ACPI_OST_SC_DEVICE_BUSY;
454 		break;
455 	default:
456 		ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
457 		break;
458 	}
459 
460  err_out:
461 	acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
462 
463  out:
464 	acpi_put_acpi_dev(adev);
465 	mutex_unlock(&acpi_scan_lock);
466 	unlock_device_hotplug();
467 }
468 
469 static void acpi_free_power_resources_lists(struct acpi_device *device)
470 {
471 	int i;
472 
473 	if (device->wakeup.flags.valid)
474 		acpi_power_resources_list_free(&device->wakeup.resources);
475 
476 	if (!device->power.flags.power_resources)
477 		return;
478 
479 	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
480 		struct acpi_device_power_state *ps = &device->power.states[i];
481 		acpi_power_resources_list_free(&ps->resources);
482 	}
483 }
484 
485 static void acpi_device_release(struct device *dev)
486 {
487 	struct acpi_device *acpi_dev = to_acpi_device(dev);
488 
489 	acpi_free_properties(acpi_dev);
490 	acpi_free_pnp_ids(&acpi_dev->pnp);
491 	acpi_free_power_resources_lists(acpi_dev);
492 	kfree(acpi_dev);
493 }
494 
495 static void acpi_device_del(struct acpi_device *device)
496 {
497 	struct acpi_device_bus_id *acpi_device_bus_id;
498 
499 	mutex_lock(&acpi_device_lock);
500 
501 	list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node)
502 		if (!strcmp(acpi_device_bus_id->bus_id,
503 			    acpi_device_hid(device))) {
504 			ida_free(&acpi_device_bus_id->instance_ida,
505 				 device->pnp.instance_no);
506 			if (ida_is_empty(&acpi_device_bus_id->instance_ida)) {
507 				list_del(&acpi_device_bus_id->node);
508 				kfree_const(acpi_device_bus_id->bus_id);
509 				kfree(acpi_device_bus_id);
510 			}
511 			break;
512 		}
513 
514 	list_del(&device->wakeup_list);
515 
516 	mutex_unlock(&acpi_device_lock);
517 
518 	acpi_power_add_remove_device(device, false);
519 	acpi_device_remove_files(device);
520 	if (device->remove)
521 		device->remove(device);
522 
523 	device_del(&device->dev);
524 }
525 
526 static BLOCKING_NOTIFIER_HEAD(acpi_reconfig_chain);
527 
528 static LIST_HEAD(acpi_device_del_list);
529 static DEFINE_MUTEX(acpi_device_del_lock);
530 
531 static void acpi_device_del_work_fn(struct work_struct *work_not_used)
532 {
533 	for (;;) {
534 		struct acpi_device *adev;
535 
536 		mutex_lock(&acpi_device_del_lock);
537 
538 		if (list_empty(&acpi_device_del_list)) {
539 			mutex_unlock(&acpi_device_del_lock);
540 			break;
541 		}
542 		adev = list_first_entry(&acpi_device_del_list,
543 					struct acpi_device, del_list);
544 		list_del(&adev->del_list);
545 
546 		mutex_unlock(&acpi_device_del_lock);
547 
548 		blocking_notifier_call_chain(&acpi_reconfig_chain,
549 					     ACPI_RECONFIG_DEVICE_REMOVE, adev);
550 
551 		acpi_device_del(adev);
552 		/*
553 		 * Drop references to all power resources that might have been
554 		 * used by the device.
555 		 */
556 		acpi_power_transition(adev, ACPI_STATE_D3_COLD);
557 		acpi_dev_put(adev);
558 	}
559 }
560 
561 /**
562  * acpi_scan_drop_device - Drop an ACPI device object.
563  * @handle: Handle of an ACPI namespace node, not used.
564  * @context: Address of the ACPI device object to drop.
565  *
566  * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
567  * namespace node the device object pointed to by @context is attached to.
568  *
569  * The unregistration is carried out asynchronously to avoid running
570  * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
571  * ensure the correct ordering (the device objects must be unregistered in the
572  * same order in which the corresponding namespace nodes are deleted).
573  */
574 static void acpi_scan_drop_device(acpi_handle handle, void *context)
575 {
576 	static DECLARE_WORK(work, acpi_device_del_work_fn);
577 	struct acpi_device *adev = context;
578 
579 	mutex_lock(&acpi_device_del_lock);
580 
581 	/*
582 	 * Use the ACPI hotplug workqueue which is ordered, so this work item
583 	 * won't run after any hotplug work items submitted subsequently.  That
584 	 * prevents attempts to register device objects identical to those being
585 	 * deleted from happening concurrently (such attempts result from
586 	 * hotplug events handled via the ACPI hotplug workqueue).  It also will
587 	 * run after all of the work items submitted previously, which helps
588 	 * those work items to ensure that they are not accessing stale device
589 	 * objects.
590 	 */
591 	if (list_empty(&acpi_device_del_list))
592 		acpi_queue_hotplug_work(&work);
593 
594 	list_add_tail(&adev->del_list, &acpi_device_del_list);
595 	/* Make acpi_ns_validate_handle() return NULL for this handle. */
596 	adev->handle = INVALID_ACPI_HANDLE;
597 
598 	mutex_unlock(&acpi_device_del_lock);
599 }
600 
601 static struct acpi_device *handle_to_device(acpi_handle handle,
602 					    void (*callback)(void *))
603 {
604 	struct acpi_device *adev = NULL;
605 	acpi_status status;
606 
607 	status = acpi_get_data_full(handle, acpi_scan_drop_device,
608 				    (void **)&adev, callback);
609 	if (ACPI_FAILURE(status) || !adev) {
610 		acpi_handle_debug(handle, "No context!\n");
611 		return NULL;
612 	}
613 	return adev;
614 }
615 
616 /**
617  * acpi_fetch_acpi_dev - Retrieve ACPI device object.
618  * @handle: ACPI handle associated with the requested ACPI device object.
619  *
620  * Return a pointer to the ACPI device object associated with @handle, if
621  * present, or NULL otherwise.
622  */
623 struct acpi_device *acpi_fetch_acpi_dev(acpi_handle handle)
624 {
625 	return handle_to_device(handle, NULL);
626 }
627 EXPORT_SYMBOL_GPL(acpi_fetch_acpi_dev);
628 
629 static void get_acpi_device(void *dev)
630 {
631 	acpi_dev_get(dev);
632 }
633 
634 /**
635  * acpi_get_acpi_dev - Retrieve ACPI device object and reference count it.
636  * @handle: ACPI handle associated with the requested ACPI device object.
637  *
638  * Return a pointer to the ACPI device object associated with @handle and bump
639  * up that object's reference counter (under the ACPI Namespace lock), if
640  * present, or return NULL otherwise.
641  *
642  * The ACPI device object reference acquired by this function needs to be
643  * dropped via acpi_dev_put().
644  */
645 struct acpi_device *acpi_get_acpi_dev(acpi_handle handle)
646 {
647 	return handle_to_device(handle, get_acpi_device);
648 }
649 EXPORT_SYMBOL_GPL(acpi_get_acpi_dev);
650 
651 static struct acpi_device_bus_id *acpi_device_bus_id_match(const char *dev_id)
652 {
653 	struct acpi_device_bus_id *acpi_device_bus_id;
654 
655 	/* Find suitable bus_id and instance number in acpi_bus_id_list. */
656 	list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
657 		if (!strcmp(acpi_device_bus_id->bus_id, dev_id))
658 			return acpi_device_bus_id;
659 	}
660 	return NULL;
661 }
662 
663 static int acpi_device_set_name(struct acpi_device *device,
664 				struct acpi_device_bus_id *acpi_device_bus_id)
665 {
666 	struct ida *instance_ida = &acpi_device_bus_id->instance_ida;
667 	int result;
668 
669 	result = ida_alloc(instance_ida, GFP_KERNEL);
670 	if (result < 0)
671 		return result;
672 
673 	device->pnp.instance_no = result;
674 	dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, result);
675 	return 0;
676 }
677 
678 int acpi_tie_acpi_dev(struct acpi_device *adev)
679 {
680 	acpi_handle handle = adev->handle;
681 	acpi_status status;
682 
683 	if (!handle)
684 		return 0;
685 
686 	status = acpi_attach_data(handle, acpi_scan_drop_device, adev);
687 	if (ACPI_FAILURE(status)) {
688 		acpi_handle_err(handle, "Unable to attach device data\n");
689 		return -ENODEV;
690 	}
691 
692 	return 0;
693 }
694 
695 static void acpi_store_pld_crc(struct acpi_device *adev)
696 {
697 	struct acpi_pld_info *pld;
698 	acpi_status status;
699 
700 	status = acpi_get_physical_device_location(adev->handle, &pld);
701 	if (ACPI_FAILURE(status))
702 		return;
703 
704 	adev->pld_crc = crc32(~0, pld, sizeof(*pld));
705 	ACPI_FREE(pld);
706 }
707 
708 int acpi_device_add(struct acpi_device *device)
709 {
710 	struct acpi_device_bus_id *acpi_device_bus_id;
711 	int result;
712 
713 	/*
714 	 * Linkage
715 	 * -------
716 	 * Link this device to its parent and siblings.
717 	 */
718 	INIT_LIST_HEAD(&device->wakeup_list);
719 	INIT_LIST_HEAD(&device->physical_node_list);
720 	INIT_LIST_HEAD(&device->del_list);
721 	mutex_init(&device->physical_node_lock);
722 
723 	mutex_lock(&acpi_device_lock);
724 
725 	acpi_device_bus_id = acpi_device_bus_id_match(acpi_device_hid(device));
726 	if (acpi_device_bus_id) {
727 		result = acpi_device_set_name(device, acpi_device_bus_id);
728 		if (result)
729 			goto err_unlock;
730 	} else {
731 		acpi_device_bus_id = kzalloc(sizeof(*acpi_device_bus_id),
732 					     GFP_KERNEL);
733 		if (!acpi_device_bus_id) {
734 			result = -ENOMEM;
735 			goto err_unlock;
736 		}
737 		acpi_device_bus_id->bus_id =
738 			kstrdup_const(acpi_device_hid(device), GFP_KERNEL);
739 		if (!acpi_device_bus_id->bus_id) {
740 			kfree(acpi_device_bus_id);
741 			result = -ENOMEM;
742 			goto err_unlock;
743 		}
744 
745 		ida_init(&acpi_device_bus_id->instance_ida);
746 
747 		result = acpi_device_set_name(device, acpi_device_bus_id);
748 		if (result) {
749 			kfree_const(acpi_device_bus_id->bus_id);
750 			kfree(acpi_device_bus_id);
751 			goto err_unlock;
752 		}
753 
754 		list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
755 	}
756 
757 	if (device->wakeup.flags.valid)
758 		list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
759 
760 	acpi_store_pld_crc(device);
761 
762 	mutex_unlock(&acpi_device_lock);
763 
764 	result = device_add(&device->dev);
765 	if (result) {
766 		dev_err(&device->dev, "Error registering device\n");
767 		goto err;
768 	}
769 
770 	result = acpi_device_setup_files(device);
771 	if (result)
772 		pr_err("Error creating sysfs interface for device %s\n",
773 		       dev_name(&device->dev));
774 
775 	return 0;
776 
777 err:
778 	mutex_lock(&acpi_device_lock);
779 
780 	list_del(&device->wakeup_list);
781 
782 err_unlock:
783 	mutex_unlock(&acpi_device_lock);
784 
785 	acpi_detach_data(device->handle, acpi_scan_drop_device);
786 
787 	return result;
788 }
789 
790 /* --------------------------------------------------------------------------
791                                  Device Enumeration
792    -------------------------------------------------------------------------- */
793 static bool acpi_info_matches_ids(struct acpi_device_info *info,
794 				  const char * const ids[])
795 {
796 	struct acpi_pnp_device_id_list *cid_list = NULL;
797 	int i, index;
798 
799 	if (!(info->valid & ACPI_VALID_HID))
800 		return false;
801 
802 	index = match_string(ids, -1, info->hardware_id.string);
803 	if (index >= 0)
804 		return true;
805 
806 	if (info->valid & ACPI_VALID_CID)
807 		cid_list = &info->compatible_id_list;
808 
809 	if (!cid_list)
810 		return false;
811 
812 	for (i = 0; i < cid_list->count; i++) {
813 		index = match_string(ids, -1, cid_list->ids[i].string);
814 		if (index >= 0)
815 			return true;
816 	}
817 
818 	return false;
819 }
820 
821 /* List of HIDs for which we ignore matching ACPI devices, when checking _DEP lists. */
822 static const char * const acpi_ignore_dep_ids[] = {
823 	"PNP0D80", /* Windows-compatible System Power Management Controller */
824 	"INT33BD", /* Intel Baytrail Mailbox Device */
825 	"LATT2021", /* Lattice FW Update Client Driver */
826 	NULL
827 };
828 
829 /* List of HIDs for which we honor deps of matching ACPI devs, when checking _DEP lists. */
830 static const char * const acpi_honor_dep_ids[] = {
831 	"INT3472", /* Camera sensor PMIC / clk and regulator info */
832 	"INTC1059", /* IVSC (TGL) driver must be loaded to allow i2c access to camera sensors */
833 	"INTC1095", /* IVSC (ADL) driver must be loaded to allow i2c access to camera sensors */
834 	"INTC100A", /* IVSC (RPL) driver must be loaded to allow i2c access to camera sensors */
835 	"INTC10CF", /* IVSC (MTL) driver must be loaded to allow i2c access to camera sensors */
836 	NULL
837 };
838 
839 static struct acpi_device *acpi_find_parent_acpi_dev(acpi_handle handle)
840 {
841 	struct acpi_device *adev;
842 
843 	/*
844 	 * Fixed hardware devices do not appear in the namespace and do not
845 	 * have handles, but we fabricate acpi_devices for them, so we have
846 	 * to deal with them specially.
847 	 */
848 	if (!handle)
849 		return acpi_root;
850 
851 	do {
852 		acpi_status status;
853 
854 		status = acpi_get_parent(handle, &handle);
855 		if (ACPI_FAILURE(status)) {
856 			if (status != AE_NULL_ENTRY)
857 				return acpi_root;
858 
859 			return NULL;
860 		}
861 		adev = acpi_fetch_acpi_dev(handle);
862 	} while (!adev);
863 	return adev;
864 }
865 
866 acpi_status
867 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
868 {
869 	acpi_status status;
870 	acpi_handle tmp;
871 	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
872 	union acpi_object *obj;
873 
874 	status = acpi_get_handle(handle, "_EJD", &tmp);
875 	if (ACPI_FAILURE(status))
876 		return status;
877 
878 	status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
879 	if (ACPI_SUCCESS(status)) {
880 		obj = buffer.pointer;
881 		status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
882 					 ejd);
883 		kfree(buffer.pointer);
884 	}
885 	return status;
886 }
887 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
888 
889 static int acpi_bus_extract_wakeup_device_power_package(struct acpi_device *dev)
890 {
891 	acpi_handle handle = dev->handle;
892 	struct acpi_device_wakeup *wakeup = &dev->wakeup;
893 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
894 	union acpi_object *package = NULL;
895 	union acpi_object *element = NULL;
896 	acpi_status status;
897 	int err = -ENODATA;
898 
899 	INIT_LIST_HEAD(&wakeup->resources);
900 
901 	/* _PRW */
902 	status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
903 	if (ACPI_FAILURE(status)) {
904 		acpi_handle_info(handle, "_PRW evaluation failed: %s\n",
905 				 acpi_format_exception(status));
906 		return err;
907 	}
908 
909 	package = (union acpi_object *)buffer.pointer;
910 
911 	if (!package || package->package.count < 2)
912 		goto out;
913 
914 	element = &(package->package.elements[0]);
915 	if (!element)
916 		goto out;
917 
918 	if (element->type == ACPI_TYPE_PACKAGE) {
919 		if ((element->package.count < 2) ||
920 		    (element->package.elements[0].type !=
921 		     ACPI_TYPE_LOCAL_REFERENCE)
922 		    || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
923 			goto out;
924 
925 		wakeup->gpe_device =
926 		    element->package.elements[0].reference.handle;
927 		wakeup->gpe_number =
928 		    (u32) element->package.elements[1].integer.value;
929 	} else if (element->type == ACPI_TYPE_INTEGER) {
930 		wakeup->gpe_device = NULL;
931 		wakeup->gpe_number = element->integer.value;
932 	} else {
933 		goto out;
934 	}
935 
936 	element = &(package->package.elements[1]);
937 	if (element->type != ACPI_TYPE_INTEGER)
938 		goto out;
939 
940 	wakeup->sleep_state = element->integer.value;
941 
942 	err = acpi_extract_power_resources(package, 2, &wakeup->resources);
943 	if (err)
944 		goto out;
945 
946 	if (!list_empty(&wakeup->resources)) {
947 		int sleep_state;
948 
949 		err = acpi_power_wakeup_list_init(&wakeup->resources,
950 						  &sleep_state);
951 		if (err) {
952 			acpi_handle_warn(handle, "Retrieving current states "
953 					 "of wakeup power resources failed\n");
954 			acpi_power_resources_list_free(&wakeup->resources);
955 			goto out;
956 		}
957 		if (sleep_state < wakeup->sleep_state) {
958 			acpi_handle_warn(handle, "Overriding _PRW sleep state "
959 					 "(S%d) by S%d from power resources\n",
960 					 (int)wakeup->sleep_state, sleep_state);
961 			wakeup->sleep_state = sleep_state;
962 		}
963 	}
964 
965  out:
966 	kfree(buffer.pointer);
967 	return err;
968 }
969 
970 /* Do not use a button for S5 wakeup */
971 #define ACPI_AVOID_WAKE_FROM_S5		BIT(0)
972 
973 static bool acpi_wakeup_gpe_init(struct acpi_device *device)
974 {
975 	static const struct acpi_device_id button_device_ids[] = {
976 		{"PNP0C0C", 0},				/* Power button */
977 		{"PNP0C0D", ACPI_AVOID_WAKE_FROM_S5},	/* Lid */
978 		{"PNP0C0E", ACPI_AVOID_WAKE_FROM_S5},	/* Sleep button */
979 		{"", 0},
980 	};
981 	struct acpi_device_wakeup *wakeup = &device->wakeup;
982 	const struct acpi_device_id *match;
983 	acpi_status status;
984 
985 	wakeup->flags.notifier_present = 0;
986 
987 	/* Power button, Lid switch always enable wakeup */
988 	match = acpi_match_acpi_device(button_device_ids, device);
989 	if (match) {
990 		if ((match->driver_data & ACPI_AVOID_WAKE_FROM_S5) &&
991 		    wakeup->sleep_state == ACPI_STATE_S5)
992 			wakeup->sleep_state = ACPI_STATE_S4;
993 		acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
994 		device_set_wakeup_capable(&device->dev, true);
995 		return true;
996 	}
997 
998 	status = acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
999 					 wakeup->gpe_number);
1000 	return ACPI_SUCCESS(status);
1001 }
1002 
1003 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
1004 {
1005 	int err;
1006 
1007 	/* Presence of _PRW indicates wake capable */
1008 	if (!acpi_has_method(device->handle, "_PRW"))
1009 		return;
1010 
1011 	err = acpi_bus_extract_wakeup_device_power_package(device);
1012 	if (err) {
1013 		dev_err(&device->dev, "Unable to extract wakeup power resources");
1014 		return;
1015 	}
1016 
1017 	device->wakeup.flags.valid = acpi_wakeup_gpe_init(device);
1018 	device->wakeup.prepare_count = 0;
1019 	/*
1020 	 * Call _PSW/_DSW object to disable its ability to wake the sleeping
1021 	 * system for the ACPI device with the _PRW object.
1022 	 * The _PSW object is deprecated in ACPI 3.0 and is replaced by _DSW.
1023 	 * So it is necessary to call _DSW object first. Only when it is not
1024 	 * present will the _PSW object used.
1025 	 */
1026 	err = acpi_device_sleep_wake(device, 0, 0, 0);
1027 	if (err)
1028 		pr_debug("error in _DSW or _PSW evaluation\n");
1029 }
1030 
1031 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
1032 {
1033 	struct acpi_device_power_state *ps = &device->power.states[state];
1034 	char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
1035 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1036 	acpi_status status;
1037 
1038 	INIT_LIST_HEAD(&ps->resources);
1039 
1040 	/* Evaluate "_PRx" to get referenced power resources */
1041 	status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
1042 	if (ACPI_SUCCESS(status)) {
1043 		union acpi_object *package = buffer.pointer;
1044 
1045 		if (buffer.length && package
1046 		    && package->type == ACPI_TYPE_PACKAGE
1047 		    && package->package.count)
1048 			acpi_extract_power_resources(package, 0, &ps->resources);
1049 
1050 		ACPI_FREE(buffer.pointer);
1051 	}
1052 
1053 	/* Evaluate "_PSx" to see if we can do explicit sets */
1054 	pathname[2] = 'S';
1055 	if (acpi_has_method(device->handle, pathname))
1056 		ps->flags.explicit_set = 1;
1057 
1058 	/* State is valid if there are means to put the device into it. */
1059 	if (!list_empty(&ps->resources) || ps->flags.explicit_set)
1060 		ps->flags.valid = 1;
1061 
1062 	ps->power = -1;		/* Unknown - driver assigned */
1063 	ps->latency = -1;	/* Unknown - driver assigned */
1064 }
1065 
1066 static void acpi_bus_get_power_flags(struct acpi_device *device)
1067 {
1068 	unsigned long long dsc = ACPI_STATE_D0;
1069 	u32 i;
1070 
1071 	/* Presence of _PS0|_PR0 indicates 'power manageable' */
1072 	if (!acpi_has_method(device->handle, "_PS0") &&
1073 	    !acpi_has_method(device->handle, "_PR0"))
1074 		return;
1075 
1076 	device->flags.power_manageable = 1;
1077 
1078 	/*
1079 	 * Power Management Flags
1080 	 */
1081 	if (acpi_has_method(device->handle, "_PSC"))
1082 		device->power.flags.explicit_get = 1;
1083 
1084 	if (acpi_has_method(device->handle, "_IRC"))
1085 		device->power.flags.inrush_current = 1;
1086 
1087 	if (acpi_has_method(device->handle, "_DSW"))
1088 		device->power.flags.dsw_present = 1;
1089 
1090 	acpi_evaluate_integer(device->handle, "_DSC", NULL, &dsc);
1091 	device->power.state_for_enumeration = dsc;
1092 
1093 	/*
1094 	 * Enumerate supported power management states
1095 	 */
1096 	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
1097 		acpi_bus_init_power_state(device, i);
1098 
1099 	INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
1100 
1101 	/* Set the defaults for D0 and D3hot (always supported). */
1102 	device->power.states[ACPI_STATE_D0].flags.valid = 1;
1103 	device->power.states[ACPI_STATE_D0].power = 100;
1104 	device->power.states[ACPI_STATE_D3_HOT].flags.valid = 1;
1105 
1106 	/*
1107 	 * Use power resources only if the D0 list of them is populated, because
1108 	 * some platforms may provide _PR3 only to indicate D3cold support and
1109 	 * in those cases the power resources list returned by it may be bogus.
1110 	 */
1111 	if (!list_empty(&device->power.states[ACPI_STATE_D0].resources)) {
1112 		device->power.flags.power_resources = 1;
1113 		/*
1114 		 * D3cold is supported if the D3hot list of power resources is
1115 		 * not empty.
1116 		 */
1117 		if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources))
1118 			device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
1119 	}
1120 
1121 	if (acpi_bus_init_power(device))
1122 		device->flags.power_manageable = 0;
1123 }
1124 
1125 static void acpi_bus_get_flags(struct acpi_device *device)
1126 {
1127 	/* Presence of _STA indicates 'dynamic_status' */
1128 	if (acpi_has_method(device->handle, "_STA"))
1129 		device->flags.dynamic_status = 1;
1130 
1131 	/* Presence of _RMV indicates 'removable' */
1132 	if (acpi_has_method(device->handle, "_RMV"))
1133 		device->flags.removable = 1;
1134 
1135 	/* Presence of _EJD|_EJ0 indicates 'ejectable' */
1136 	if (acpi_has_method(device->handle, "_EJD") ||
1137 	    acpi_has_method(device->handle, "_EJ0"))
1138 		device->flags.ejectable = 1;
1139 }
1140 
1141 static void acpi_device_get_busid(struct acpi_device *device)
1142 {
1143 	char bus_id[5] = { '?', 0 };
1144 	struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1145 	int i = 0;
1146 
1147 	/*
1148 	 * Bus ID
1149 	 * ------
1150 	 * The device's Bus ID is simply the object name.
1151 	 * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1152 	 */
1153 	if (!acpi_dev_parent(device)) {
1154 		strcpy(device->pnp.bus_id, "ACPI");
1155 		return;
1156 	}
1157 
1158 	switch (device->device_type) {
1159 	case ACPI_BUS_TYPE_POWER_BUTTON:
1160 		strcpy(device->pnp.bus_id, "PWRF");
1161 		break;
1162 	case ACPI_BUS_TYPE_SLEEP_BUTTON:
1163 		strcpy(device->pnp.bus_id, "SLPF");
1164 		break;
1165 	case ACPI_BUS_TYPE_ECDT_EC:
1166 		strcpy(device->pnp.bus_id, "ECDT");
1167 		break;
1168 	default:
1169 		acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1170 		/* Clean up trailing underscores (if any) */
1171 		for (i = 3; i > 1; i--) {
1172 			if (bus_id[i] == '_')
1173 				bus_id[i] = '\0';
1174 			else
1175 				break;
1176 		}
1177 		strcpy(device->pnp.bus_id, bus_id);
1178 		break;
1179 	}
1180 }
1181 
1182 /*
1183  * acpi_ata_match - see if an acpi object is an ATA device
1184  *
1185  * If an acpi object has one of the ACPI ATA methods defined,
1186  * then we can safely call it an ATA device.
1187  */
1188 bool acpi_ata_match(acpi_handle handle)
1189 {
1190 	return acpi_has_method(handle, "_GTF") ||
1191 	       acpi_has_method(handle, "_GTM") ||
1192 	       acpi_has_method(handle, "_STM") ||
1193 	       acpi_has_method(handle, "_SDD");
1194 }
1195 
1196 /*
1197  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1198  *
1199  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1200  * then we can safely call it an ejectable drive bay
1201  */
1202 bool acpi_bay_match(acpi_handle handle)
1203 {
1204 	acpi_handle phandle;
1205 
1206 	if (!acpi_has_method(handle, "_EJ0"))
1207 		return false;
1208 	if (acpi_ata_match(handle))
1209 		return true;
1210 	if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1211 		return false;
1212 
1213 	return acpi_ata_match(phandle);
1214 }
1215 
1216 bool acpi_device_is_battery(struct acpi_device *adev)
1217 {
1218 	struct acpi_hardware_id *hwid;
1219 
1220 	list_for_each_entry(hwid, &adev->pnp.ids, list)
1221 		if (!strcmp("PNP0C0A", hwid->id))
1222 			return true;
1223 
1224 	return false;
1225 }
1226 
1227 static bool is_ejectable_bay(struct acpi_device *adev)
1228 {
1229 	acpi_handle handle = adev->handle;
1230 
1231 	if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
1232 		return true;
1233 
1234 	return acpi_bay_match(handle);
1235 }
1236 
1237 /*
1238  * acpi_dock_match - see if an acpi object has a _DCK method
1239  */
1240 bool acpi_dock_match(acpi_handle handle)
1241 {
1242 	return acpi_has_method(handle, "_DCK");
1243 }
1244 
1245 static acpi_status
1246 acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
1247 			  void **return_value)
1248 {
1249 	long *cap = context;
1250 
1251 	if (acpi_has_method(handle, "_BCM") &&
1252 	    acpi_has_method(handle, "_BCL")) {
1253 		acpi_handle_debug(handle, "Found generic backlight support\n");
1254 		*cap |= ACPI_VIDEO_BACKLIGHT;
1255 		/* We have backlight support, no need to scan further */
1256 		return AE_CTRL_TERMINATE;
1257 	}
1258 	return 0;
1259 }
1260 
1261 /* Returns true if the ACPI object is a video device which can be
1262  * handled by video.ko.
1263  * The device will get a Linux specific CID added in scan.c to
1264  * identify the device as an ACPI graphics device
1265  * Be aware that the graphics device may not be physically present
1266  * Use acpi_video_get_capabilities() to detect general ACPI video
1267  * capabilities of present cards
1268  */
1269 long acpi_is_video_device(acpi_handle handle)
1270 {
1271 	long video_caps = 0;
1272 
1273 	/* Is this device able to support video switching ? */
1274 	if (acpi_has_method(handle, "_DOD") || acpi_has_method(handle, "_DOS"))
1275 		video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
1276 
1277 	/* Is this device able to retrieve a video ROM ? */
1278 	if (acpi_has_method(handle, "_ROM"))
1279 		video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
1280 
1281 	/* Is this device able to configure which video head to be POSTed ? */
1282 	if (acpi_has_method(handle, "_VPO") &&
1283 	    acpi_has_method(handle, "_GPD") &&
1284 	    acpi_has_method(handle, "_SPD"))
1285 		video_caps |= ACPI_VIDEO_DEVICE_POSTING;
1286 
1287 	/* Only check for backlight functionality if one of the above hit. */
1288 	if (video_caps)
1289 		acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
1290 				    ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
1291 				    &video_caps, NULL);
1292 
1293 	return video_caps;
1294 }
1295 EXPORT_SYMBOL(acpi_is_video_device);
1296 
1297 const char *acpi_device_hid(struct acpi_device *device)
1298 {
1299 	struct acpi_hardware_id *hid;
1300 
1301 	if (list_empty(&device->pnp.ids))
1302 		return dummy_hid;
1303 
1304 	hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1305 	return hid->id;
1306 }
1307 EXPORT_SYMBOL(acpi_device_hid);
1308 
1309 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1310 {
1311 	struct acpi_hardware_id *id;
1312 
1313 	id = kmalloc(sizeof(*id), GFP_KERNEL);
1314 	if (!id)
1315 		return;
1316 
1317 	id->id = kstrdup_const(dev_id, GFP_KERNEL);
1318 	if (!id->id) {
1319 		kfree(id);
1320 		return;
1321 	}
1322 
1323 	list_add_tail(&id->list, &pnp->ids);
1324 	pnp->type.hardware_id = 1;
1325 }
1326 
1327 /*
1328  * Old IBM workstations have a DSDT bug wherein the SMBus object
1329  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1330  * prefix.  Work around this.
1331  */
1332 static bool acpi_ibm_smbus_match(acpi_handle handle)
1333 {
1334 	char node_name[ACPI_PATH_SEGMENT_LENGTH];
1335 	struct acpi_buffer path = { sizeof(node_name), node_name };
1336 
1337 	if (!dmi_name_in_vendors("IBM"))
1338 		return false;
1339 
1340 	/* Look for SMBS object */
1341 	if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1342 	    strcmp("SMBS", path.pointer))
1343 		return false;
1344 
1345 	/* Does it have the necessary (but misnamed) methods? */
1346 	if (acpi_has_method(handle, "SBI") &&
1347 	    acpi_has_method(handle, "SBR") &&
1348 	    acpi_has_method(handle, "SBW"))
1349 		return true;
1350 
1351 	return false;
1352 }
1353 
1354 static bool acpi_object_is_system_bus(acpi_handle handle)
1355 {
1356 	acpi_handle tmp;
1357 
1358 	if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
1359 	    tmp == handle)
1360 		return true;
1361 	if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
1362 	    tmp == handle)
1363 		return true;
1364 
1365 	return false;
1366 }
1367 
1368 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1369 			     int device_type)
1370 {
1371 	struct acpi_device_info *info = NULL;
1372 	struct acpi_pnp_device_id_list *cid_list;
1373 	int i;
1374 
1375 	switch (device_type) {
1376 	case ACPI_BUS_TYPE_DEVICE:
1377 		if (handle == ACPI_ROOT_OBJECT) {
1378 			acpi_add_id(pnp, ACPI_SYSTEM_HID);
1379 			break;
1380 		}
1381 
1382 		acpi_get_object_info(handle, &info);
1383 		if (!info) {
1384 			pr_err("%s: Error reading device info\n", __func__);
1385 			return;
1386 		}
1387 
1388 		if (info->valid & ACPI_VALID_HID) {
1389 			acpi_add_id(pnp, info->hardware_id.string);
1390 			pnp->type.platform_id = 1;
1391 		}
1392 		if (info->valid & ACPI_VALID_CID) {
1393 			cid_list = &info->compatible_id_list;
1394 			for (i = 0; i < cid_list->count; i++)
1395 				acpi_add_id(pnp, cid_list->ids[i].string);
1396 		}
1397 		if (info->valid & ACPI_VALID_ADR) {
1398 			pnp->bus_address = info->address;
1399 			pnp->type.bus_address = 1;
1400 		}
1401 		if (info->valid & ACPI_VALID_UID)
1402 			pnp->unique_id = kstrdup(info->unique_id.string,
1403 							GFP_KERNEL);
1404 		if (info->valid & ACPI_VALID_CLS)
1405 			acpi_add_id(pnp, info->class_code.string);
1406 
1407 		kfree(info);
1408 
1409 		/*
1410 		 * Some devices don't reliably have _HIDs & _CIDs, so add
1411 		 * synthetic HIDs to make sure drivers can find them.
1412 		 */
1413 		if (acpi_is_video_device(handle)) {
1414 			acpi_add_id(pnp, ACPI_VIDEO_HID);
1415 			pnp->type.backlight = 1;
1416 			break;
1417 		}
1418 		if (acpi_bay_match(handle))
1419 			acpi_add_id(pnp, ACPI_BAY_HID);
1420 		else if (acpi_dock_match(handle))
1421 			acpi_add_id(pnp, ACPI_DOCK_HID);
1422 		else if (acpi_ibm_smbus_match(handle))
1423 			acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1424 		else if (list_empty(&pnp->ids) &&
1425 			 acpi_object_is_system_bus(handle)) {
1426 			/* \_SB, \_TZ, LNXSYBUS */
1427 			acpi_add_id(pnp, ACPI_BUS_HID);
1428 			strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1429 			strcpy(pnp->device_class, ACPI_BUS_CLASS);
1430 		}
1431 
1432 		break;
1433 	case ACPI_BUS_TYPE_POWER:
1434 		acpi_add_id(pnp, ACPI_POWER_HID);
1435 		break;
1436 	case ACPI_BUS_TYPE_PROCESSOR:
1437 		acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1438 		break;
1439 	case ACPI_BUS_TYPE_THERMAL:
1440 		acpi_add_id(pnp, ACPI_THERMAL_HID);
1441 		break;
1442 	case ACPI_BUS_TYPE_POWER_BUTTON:
1443 		acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1444 		break;
1445 	case ACPI_BUS_TYPE_SLEEP_BUTTON:
1446 		acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1447 		break;
1448 	case ACPI_BUS_TYPE_ECDT_EC:
1449 		acpi_add_id(pnp, ACPI_ECDT_HID);
1450 		break;
1451 	}
1452 }
1453 
1454 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1455 {
1456 	struct acpi_hardware_id *id, *tmp;
1457 
1458 	list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1459 		kfree_const(id->id);
1460 		kfree(id);
1461 	}
1462 	kfree(pnp->unique_id);
1463 }
1464 
1465 /**
1466  * acpi_dma_supported - Check DMA support for the specified device.
1467  * @adev: The pointer to acpi device
1468  *
1469  * Return false if DMA is not supported. Otherwise, return true
1470  */
1471 bool acpi_dma_supported(const struct acpi_device *adev)
1472 {
1473 	if (!adev)
1474 		return false;
1475 
1476 	if (adev->flags.cca_seen)
1477 		return true;
1478 
1479 	/*
1480 	* Per ACPI 6.0 sec 6.2.17, assume devices can do cache-coherent
1481 	* DMA on "Intel platforms".  Presumably that includes all x86 and
1482 	* ia64, and other arches will set CONFIG_ACPI_CCA_REQUIRED=y.
1483 	*/
1484 	if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1485 		return true;
1486 
1487 	return false;
1488 }
1489 
1490 /**
1491  * acpi_get_dma_attr - Check the supported DMA attr for the specified device.
1492  * @adev: The pointer to acpi device
1493  *
1494  * Return enum dev_dma_attr.
1495  */
1496 enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
1497 {
1498 	if (!acpi_dma_supported(adev))
1499 		return DEV_DMA_NOT_SUPPORTED;
1500 
1501 	if (adev->flags.coherent_dma)
1502 		return DEV_DMA_COHERENT;
1503 	else
1504 		return DEV_DMA_NON_COHERENT;
1505 }
1506 
1507 /**
1508  * acpi_dma_get_range() - Get device DMA parameters.
1509  *
1510  * @dev: device to configure
1511  * @map: pointer to DMA ranges result
1512  *
1513  * Evaluate DMA regions and return pointer to DMA regions on
1514  * parsing success; it does not update the passed in values on failure.
1515  *
1516  * Return 0 on success, < 0 on failure.
1517  */
1518 int acpi_dma_get_range(struct device *dev, const struct bus_dma_region **map)
1519 {
1520 	struct acpi_device *adev;
1521 	LIST_HEAD(list);
1522 	struct resource_entry *rentry;
1523 	int ret;
1524 	struct device *dma_dev = dev;
1525 	struct bus_dma_region *r;
1526 
1527 	/*
1528 	 * Walk the device tree chasing an ACPI companion with a _DMA
1529 	 * object while we go. Stop if we find a device with an ACPI
1530 	 * companion containing a _DMA method.
1531 	 */
1532 	do {
1533 		adev = ACPI_COMPANION(dma_dev);
1534 		if (adev && acpi_has_method(adev->handle, METHOD_NAME__DMA))
1535 			break;
1536 
1537 		dma_dev = dma_dev->parent;
1538 	} while (dma_dev);
1539 
1540 	if (!dma_dev)
1541 		return -ENODEV;
1542 
1543 	if (!acpi_has_method(adev->handle, METHOD_NAME__CRS)) {
1544 		acpi_handle_warn(adev->handle, "_DMA is valid only if _CRS is present\n");
1545 		return -EINVAL;
1546 	}
1547 
1548 	ret = acpi_dev_get_dma_resources(adev, &list);
1549 	if (ret > 0) {
1550 		r = kcalloc(ret + 1, sizeof(*r), GFP_KERNEL);
1551 		if (!r) {
1552 			ret = -ENOMEM;
1553 			goto out;
1554 		}
1555 
1556 		*map = r;
1557 
1558 		list_for_each_entry(rentry, &list, node) {
1559 			if (rentry->res->start >= rentry->res->end) {
1560 				kfree(*map);
1561 				*map = NULL;
1562 				ret = -EINVAL;
1563 				dev_dbg(dma_dev, "Invalid DMA regions configuration\n");
1564 				goto out;
1565 			}
1566 
1567 			r->cpu_start = rentry->res->start;
1568 			r->dma_start = rentry->res->start - rentry->offset;
1569 			r->size = resource_size(rentry->res);
1570 			r++;
1571 		}
1572 	}
1573  out:
1574 	acpi_dev_free_resource_list(&list);
1575 
1576 	return ret >= 0 ? 0 : ret;
1577 }
1578 
1579 #ifdef CONFIG_IOMMU_API
1580 int acpi_iommu_fwspec_init(struct device *dev, u32 id,
1581 			   struct fwnode_handle *fwnode,
1582 			   const struct iommu_ops *ops)
1583 {
1584 	int ret = iommu_fwspec_init(dev, fwnode, ops);
1585 
1586 	if (!ret)
1587 		ret = iommu_fwspec_add_ids(dev, &id, 1);
1588 
1589 	return ret;
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 	/* Ignore all other errors apart from EPROBE_DEFER */
1629 	if (err == -EPROBE_DEFER) {
1630 		return err;
1631 	} else if (err) {
1632 		dev_dbg(dev, "Adding to IOMMU failed: %d\n", err);
1633 		return -ENODEV;
1634 	}
1635 	if (!acpi_iommu_fwspec_ops(dev))
1636 		return -ENODEV;
1637 	return 0;
1638 }
1639 
1640 #else /* !CONFIG_IOMMU_API */
1641 
1642 int acpi_iommu_fwspec_init(struct device *dev, u32 id,
1643 			   struct fwnode_handle *fwnode,
1644 			   const struct iommu_ops *ops)
1645 {
1646 	return -ENODEV;
1647 }
1648 
1649 static int acpi_iommu_configure_id(struct device *dev, const u32 *id_in)
1650 {
1651 	return -ENODEV;
1652 }
1653 
1654 #endif /* !CONFIG_IOMMU_API */
1655 
1656 /**
1657  * acpi_dma_configure_id - Set-up DMA configuration for the device.
1658  * @dev: The pointer to the device
1659  * @attr: device dma attributes
1660  * @input_id: input device id const value pointer
1661  */
1662 int acpi_dma_configure_id(struct device *dev, enum dev_dma_attr attr,
1663 			  const u32 *input_id)
1664 {
1665 	int ret;
1666 
1667 	if (attr == DEV_DMA_NOT_SUPPORTED) {
1668 		set_dma_ops(dev, &dma_dummy_ops);
1669 		return 0;
1670 	}
1671 
1672 	acpi_arch_dma_setup(dev);
1673 
1674 	ret = acpi_iommu_configure_id(dev, input_id);
1675 	if (ret == -EPROBE_DEFER)
1676 		return -EPROBE_DEFER;
1677 
1678 	/*
1679 	 * Historically this routine doesn't fail driver probing due to errors
1680 	 * in acpi_iommu_configure_id()
1681 	 */
1682 
1683 	arch_setup_dma_ops(dev, 0, U64_MAX, attr == DEV_DMA_COHERENT);
1684 
1685 	return 0;
1686 }
1687 EXPORT_SYMBOL_GPL(acpi_dma_configure_id);
1688 
1689 static void acpi_init_coherency(struct acpi_device *adev)
1690 {
1691 	unsigned long long cca = 0;
1692 	acpi_status status;
1693 	struct acpi_device *parent = acpi_dev_parent(adev);
1694 
1695 	if (parent && parent->flags.cca_seen) {
1696 		/*
1697 		 * From ACPI spec, OSPM will ignore _CCA if an ancestor
1698 		 * already saw one.
1699 		 */
1700 		adev->flags.cca_seen = 1;
1701 		cca = parent->flags.coherent_dma;
1702 	} else {
1703 		status = acpi_evaluate_integer(adev->handle, "_CCA",
1704 					       NULL, &cca);
1705 		if (ACPI_SUCCESS(status))
1706 			adev->flags.cca_seen = 1;
1707 		else if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1708 			/*
1709 			 * If architecture does not specify that _CCA is
1710 			 * required for DMA-able devices (e.g. x86),
1711 			 * we default to _CCA=1.
1712 			 */
1713 			cca = 1;
1714 		else
1715 			acpi_handle_debug(adev->handle,
1716 					  "ACPI device is missing _CCA.\n");
1717 	}
1718 
1719 	adev->flags.coherent_dma = cca;
1720 }
1721 
1722 static int acpi_check_serial_bus_slave(struct acpi_resource *ares, void *data)
1723 {
1724 	bool *is_serial_bus_slave_p = data;
1725 
1726 	if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
1727 		return 1;
1728 
1729 	*is_serial_bus_slave_p = true;
1730 
1731 	 /* no need to do more checking */
1732 	return -1;
1733 }
1734 
1735 static bool acpi_is_indirect_io_slave(struct acpi_device *device)
1736 {
1737 	struct acpi_device *parent = acpi_dev_parent(device);
1738 	static const struct acpi_device_id indirect_io_hosts[] = {
1739 		{"HISI0191", 0},
1740 		{}
1741 	};
1742 
1743 	return parent && !acpi_match_device_ids(parent, indirect_io_hosts);
1744 }
1745 
1746 static bool acpi_device_enumeration_by_parent(struct acpi_device *device)
1747 {
1748 	struct list_head resource_list;
1749 	bool is_serial_bus_slave = false;
1750 	static const struct acpi_device_id ignore_serial_bus_ids[] = {
1751 	/*
1752 	 * These devices have multiple SerialBus resources and a client
1753 	 * device must be instantiated for each of them, each with
1754 	 * its own device id.
1755 	 * Normally we only instantiate one client device for the first
1756 	 * resource, using the ACPI HID as id. These special cases are handled
1757 	 * by the drivers/platform/x86/serial-multi-instantiate.c driver, which
1758 	 * knows which client device id to use for each resource.
1759 	 */
1760 		{"BSG1160", },
1761 		{"BSG2150", },
1762 		{"CSC3551", },
1763 		{"CSC3554", },
1764 		{"CSC3556", },
1765 		{"CSC3557", },
1766 		{"INT33FE", },
1767 		{"INT3515", },
1768 		/* Non-conforming _HID for Cirrus Logic already released */
1769 		{"CLSA0100", },
1770 		{"CLSA0101", },
1771 	/*
1772 	 * Some ACPI devs contain SerialBus resources even though they are not
1773 	 * attached to a serial bus at all.
1774 	 */
1775 		{ACPI_VIDEO_HID, },
1776 		{"MSHW0028", },
1777 	/*
1778 	 * HIDs of device with an UartSerialBusV2 resource for which userspace
1779 	 * expects a regular tty cdev to be created (instead of the in kernel
1780 	 * serdev) and which have a kernel driver which expects a platform_dev
1781 	 * such as the rfkill-gpio driver.
1782 	 */
1783 		{"BCM4752", },
1784 		{"LNV4752", },
1785 		{}
1786 	};
1787 
1788 	if (acpi_is_indirect_io_slave(device))
1789 		return true;
1790 
1791 	/* Macs use device properties in lieu of _CRS resources */
1792 	if (x86_apple_machine &&
1793 	    (fwnode_property_present(&device->fwnode, "spiSclkPeriod") ||
1794 	     fwnode_property_present(&device->fwnode, "i2cAddress") ||
1795 	     fwnode_property_present(&device->fwnode, "baud")))
1796 		return true;
1797 
1798 	if (!acpi_match_device_ids(device, ignore_serial_bus_ids))
1799 		return false;
1800 
1801 	INIT_LIST_HEAD(&resource_list);
1802 	acpi_dev_get_resources(device, &resource_list,
1803 			       acpi_check_serial_bus_slave,
1804 			       &is_serial_bus_slave);
1805 	acpi_dev_free_resource_list(&resource_list);
1806 
1807 	return is_serial_bus_slave;
1808 }
1809 
1810 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1811 			     int type, void (*release)(struct device *))
1812 {
1813 	struct acpi_device *parent = acpi_find_parent_acpi_dev(handle);
1814 
1815 	INIT_LIST_HEAD(&device->pnp.ids);
1816 	device->device_type = type;
1817 	device->handle = handle;
1818 	device->dev.parent = parent ? &parent->dev : NULL;
1819 	device->dev.release = release;
1820 	device->dev.bus = &acpi_bus_type;
1821 	fwnode_init(&device->fwnode, &acpi_device_fwnode_ops);
1822 	acpi_set_device_status(device, ACPI_STA_DEFAULT);
1823 	acpi_device_get_busid(device);
1824 	acpi_set_pnp_ids(handle, &device->pnp, type);
1825 	acpi_init_properties(device);
1826 	acpi_bus_get_flags(device);
1827 	device->flags.match_driver = false;
1828 	device->flags.initialized = true;
1829 	device->flags.enumeration_by_parent =
1830 		acpi_device_enumeration_by_parent(device);
1831 	acpi_device_clear_enumerated(device);
1832 	device_initialize(&device->dev);
1833 	dev_set_uevent_suppress(&device->dev, true);
1834 	acpi_init_coherency(device);
1835 }
1836 
1837 static void acpi_scan_dep_init(struct acpi_device *adev)
1838 {
1839 	struct acpi_dep_data *dep;
1840 
1841 	list_for_each_entry(dep, &acpi_dep_list, node) {
1842 		if (dep->consumer == adev->handle) {
1843 			if (dep->honor_dep)
1844 				adev->flags.honor_deps = 1;
1845 
1846 			if (!dep->met)
1847 				adev->dep_unmet++;
1848 		}
1849 	}
1850 }
1851 
1852 void acpi_device_add_finalize(struct acpi_device *device)
1853 {
1854 	dev_set_uevent_suppress(&device->dev, false);
1855 	kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1856 }
1857 
1858 static void acpi_scan_init_status(struct acpi_device *adev)
1859 {
1860 	if (acpi_bus_get_status(adev))
1861 		acpi_set_device_status(adev, 0);
1862 }
1863 
1864 static int acpi_add_single_object(struct acpi_device **child,
1865 				  acpi_handle handle, int type, bool dep_init)
1866 {
1867 	struct acpi_device *device;
1868 	bool release_dep_lock = false;
1869 	int result;
1870 
1871 	device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1872 	if (!device)
1873 		return -ENOMEM;
1874 
1875 	acpi_init_device_object(device, handle, type, acpi_device_release);
1876 	/*
1877 	 * Getting the status is delayed till here so that we can call
1878 	 * acpi_bus_get_status() and use its quirk handling.  Note that
1879 	 * this must be done before the get power-/wakeup_dev-flags calls.
1880 	 */
1881 	if (type == ACPI_BUS_TYPE_DEVICE || type == ACPI_BUS_TYPE_PROCESSOR) {
1882 		if (dep_init) {
1883 			mutex_lock(&acpi_dep_list_lock);
1884 			/*
1885 			 * Hold the lock until the acpi_tie_acpi_dev() call
1886 			 * below to prevent concurrent acpi_scan_clear_dep()
1887 			 * from deleting a dependency list entry without
1888 			 * updating dep_unmet for the device.
1889 			 */
1890 			release_dep_lock = true;
1891 			acpi_scan_dep_init(device);
1892 		}
1893 		acpi_scan_init_status(device);
1894 	}
1895 
1896 	acpi_bus_get_power_flags(device);
1897 	acpi_bus_get_wakeup_device_flags(device);
1898 
1899 	result = acpi_tie_acpi_dev(device);
1900 
1901 	if (release_dep_lock)
1902 		mutex_unlock(&acpi_dep_list_lock);
1903 
1904 	if (!result)
1905 		result = acpi_device_add(device);
1906 
1907 	if (result) {
1908 		acpi_device_release(&device->dev);
1909 		return result;
1910 	}
1911 
1912 	acpi_power_add_remove_device(device, true);
1913 	acpi_device_add_finalize(device);
1914 
1915 	acpi_handle_debug(handle, "Added as %s, parent %s\n",
1916 			  dev_name(&device->dev), device->dev.parent ?
1917 				dev_name(device->dev.parent) : "(null)");
1918 
1919 	*child = device;
1920 	return 0;
1921 }
1922 
1923 static acpi_status acpi_get_resource_memory(struct acpi_resource *ares,
1924 					    void *context)
1925 {
1926 	struct resource *res = context;
1927 
1928 	if (acpi_dev_resource_memory(ares, res))
1929 		return AE_CTRL_TERMINATE;
1930 
1931 	return AE_OK;
1932 }
1933 
1934 static bool acpi_device_should_be_hidden(acpi_handle handle)
1935 {
1936 	acpi_status status;
1937 	struct resource res;
1938 
1939 	/* Check if it should ignore the UART device */
1940 	if (!(spcr_uart_addr && acpi_has_method(handle, METHOD_NAME__CRS)))
1941 		return false;
1942 
1943 	/*
1944 	 * The UART device described in SPCR table is assumed to have only one
1945 	 * memory resource present. So we only look for the first one here.
1946 	 */
1947 	status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1948 				     acpi_get_resource_memory, &res);
1949 	if (ACPI_FAILURE(status) || res.start != spcr_uart_addr)
1950 		return false;
1951 
1952 	acpi_handle_info(handle, "The UART device @%pa in SPCR table will be hidden\n",
1953 			 &res.start);
1954 
1955 	return true;
1956 }
1957 
1958 bool acpi_device_is_present(const struct acpi_device *adev)
1959 {
1960 	return adev->status.present || adev->status.functional;
1961 }
1962 
1963 bool acpi_device_is_enabled(const struct acpi_device *adev)
1964 {
1965 	return adev->status.present && adev->status.enabled;
1966 }
1967 
1968 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1969 				       const char *idstr,
1970 				       const struct acpi_device_id **matchid)
1971 {
1972 	const struct acpi_device_id *devid;
1973 
1974 	if (handler->match)
1975 		return handler->match(idstr, matchid);
1976 
1977 	for (devid = handler->ids; devid->id[0]; devid++)
1978 		if (!strcmp((char *)devid->id, idstr)) {
1979 			if (matchid)
1980 				*matchid = devid;
1981 
1982 			return true;
1983 		}
1984 
1985 	return false;
1986 }
1987 
1988 static struct acpi_scan_handler *acpi_scan_match_handler(const char *idstr,
1989 					const struct acpi_device_id **matchid)
1990 {
1991 	struct acpi_scan_handler *handler;
1992 
1993 	list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1994 		if (acpi_scan_handler_matching(handler, idstr, matchid))
1995 			return handler;
1996 
1997 	return NULL;
1998 }
1999 
2000 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
2001 {
2002 	if (!!hotplug->enabled == !!val)
2003 		return;
2004 
2005 	mutex_lock(&acpi_scan_lock);
2006 
2007 	hotplug->enabled = val;
2008 
2009 	mutex_unlock(&acpi_scan_lock);
2010 }
2011 
2012 static void acpi_scan_init_hotplug(struct acpi_device *adev)
2013 {
2014 	struct acpi_hardware_id *hwid;
2015 
2016 	if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
2017 		acpi_dock_add(adev);
2018 		return;
2019 	}
2020 	list_for_each_entry(hwid, &adev->pnp.ids, list) {
2021 		struct acpi_scan_handler *handler;
2022 
2023 		handler = acpi_scan_match_handler(hwid->id, NULL);
2024 		if (handler) {
2025 			adev->flags.hotplug_notify = true;
2026 			break;
2027 		}
2028 	}
2029 }
2030 
2031 static u32 acpi_scan_check_dep(acpi_handle handle)
2032 {
2033 	struct acpi_handle_list dep_devices;
2034 	u32 count;
2035 	int i;
2036 
2037 	/*
2038 	 * Check for _HID here to avoid deferring the enumeration of:
2039 	 * 1. PCI devices.
2040 	 * 2. ACPI nodes describing USB ports.
2041 	 * Still, checking for _HID catches more then just these cases ...
2042 	 */
2043 	if (!acpi_has_method(handle, "_DEP") || !acpi_has_method(handle, "_HID"))
2044 		return 0;
2045 
2046 	if (!acpi_evaluate_reference(handle, "_DEP", NULL, &dep_devices)) {
2047 		acpi_handle_debug(handle, "Failed to evaluate _DEP.\n");
2048 		return 0;
2049 	}
2050 
2051 	for (count = 0, i = 0; i < dep_devices.count; i++) {
2052 		struct acpi_device_info *info;
2053 		struct acpi_dep_data *dep;
2054 		bool skip, honor_dep;
2055 		acpi_status status;
2056 
2057 		status = acpi_get_object_info(dep_devices.handles[i], &info);
2058 		if (ACPI_FAILURE(status)) {
2059 			acpi_handle_debug(handle, "Error reading _DEP device info\n");
2060 			continue;
2061 		}
2062 
2063 		skip = acpi_info_matches_ids(info, acpi_ignore_dep_ids);
2064 		honor_dep = acpi_info_matches_ids(info, acpi_honor_dep_ids);
2065 		kfree(info);
2066 
2067 		if (skip)
2068 			continue;
2069 
2070 		dep = kzalloc(sizeof(*dep), GFP_KERNEL);
2071 		if (!dep)
2072 			continue;
2073 
2074 		count++;
2075 
2076 		dep->supplier = dep_devices.handles[i];
2077 		dep->consumer = handle;
2078 		dep->honor_dep = honor_dep;
2079 
2080 		mutex_lock(&acpi_dep_list_lock);
2081 		list_add_tail(&dep->node , &acpi_dep_list);
2082 		mutex_unlock(&acpi_dep_list_lock);
2083 	}
2084 
2085 	acpi_handle_list_free(&dep_devices);
2086 	return count;
2087 }
2088 
2089 static acpi_status acpi_scan_check_crs_csi2_cb(acpi_handle handle, u32 a, void *b, void **c)
2090 {
2091 	acpi_mipi_check_crs_csi2(handle);
2092 	return AE_OK;
2093 }
2094 
2095 static acpi_status acpi_bus_check_add(acpi_handle handle, bool first_pass,
2096 				      struct acpi_device **adev_p)
2097 {
2098 	struct acpi_device *device = acpi_fetch_acpi_dev(handle);
2099 	acpi_object_type acpi_type;
2100 	int type;
2101 
2102 	if (device)
2103 		goto out;
2104 
2105 	if (ACPI_FAILURE(acpi_get_type(handle, &acpi_type)))
2106 		return AE_OK;
2107 
2108 	switch (acpi_type) {
2109 	case ACPI_TYPE_DEVICE:
2110 		if (acpi_device_should_be_hidden(handle))
2111 			return AE_OK;
2112 
2113 		if (first_pass) {
2114 			acpi_mipi_check_crs_csi2(handle);
2115 
2116 			/* Bail out if there are dependencies. */
2117 			if (acpi_scan_check_dep(handle) > 0) {
2118 				/*
2119 				 * The entire CSI-2 connection graph needs to be
2120 				 * extracted before any drivers or scan handlers
2121 				 * are bound to struct device objects, so scan
2122 				 * _CRS CSI-2 resource descriptors for all
2123 				 * devices below the current handle.
2124 				 */
2125 				acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
2126 						    ACPI_UINT32_MAX,
2127 						    acpi_scan_check_crs_csi2_cb,
2128 						    NULL, NULL, NULL);
2129 				return AE_CTRL_DEPTH;
2130 			}
2131 		}
2132 
2133 		fallthrough;
2134 	case ACPI_TYPE_ANY:	/* for ACPI_ROOT_OBJECT */
2135 		type = ACPI_BUS_TYPE_DEVICE;
2136 		break;
2137 
2138 	case ACPI_TYPE_PROCESSOR:
2139 		type = ACPI_BUS_TYPE_PROCESSOR;
2140 		break;
2141 
2142 	case ACPI_TYPE_THERMAL:
2143 		type = ACPI_BUS_TYPE_THERMAL;
2144 		break;
2145 
2146 	case ACPI_TYPE_POWER:
2147 		acpi_add_power_resource(handle);
2148 		fallthrough;
2149 	default:
2150 		return AE_OK;
2151 	}
2152 
2153 	/*
2154 	 * If first_pass is true at this point, the device has no dependencies,
2155 	 * or the creation of the device object would have been postponed above.
2156 	 */
2157 	acpi_add_single_object(&device, handle, type, !first_pass);
2158 	if (!device)
2159 		return AE_CTRL_DEPTH;
2160 
2161 	acpi_scan_init_hotplug(device);
2162 
2163 out:
2164 	if (!*adev_p)
2165 		*adev_p = device;
2166 
2167 	return AE_OK;
2168 }
2169 
2170 static acpi_status acpi_bus_check_add_1(acpi_handle handle, u32 lvl_not_used,
2171 					void *not_used, void **ret_p)
2172 {
2173 	return acpi_bus_check_add(handle, true, (struct acpi_device **)ret_p);
2174 }
2175 
2176 static acpi_status acpi_bus_check_add_2(acpi_handle handle, u32 lvl_not_used,
2177 					void *not_used, void **ret_p)
2178 {
2179 	return acpi_bus_check_add(handle, false, (struct acpi_device **)ret_p);
2180 }
2181 
2182 static void acpi_default_enumeration(struct acpi_device *device)
2183 {
2184 	/*
2185 	 * Do not enumerate devices with enumeration_by_parent flag set as
2186 	 * they will be enumerated by their respective parents.
2187 	 */
2188 	if (!device->flags.enumeration_by_parent) {
2189 		acpi_create_platform_device(device, NULL);
2190 		acpi_device_set_enumerated(device);
2191 	} else {
2192 		blocking_notifier_call_chain(&acpi_reconfig_chain,
2193 					     ACPI_RECONFIG_DEVICE_ADD, device);
2194 	}
2195 }
2196 
2197 static const struct acpi_device_id generic_device_ids[] = {
2198 	{ACPI_DT_NAMESPACE_HID, },
2199 	{"", },
2200 };
2201 
2202 static int acpi_generic_device_attach(struct acpi_device *adev,
2203 				      const struct acpi_device_id *not_used)
2204 {
2205 	/*
2206 	 * Since ACPI_DT_NAMESPACE_HID is the only ID handled here, the test
2207 	 * below can be unconditional.
2208 	 */
2209 	if (adev->data.of_compatible)
2210 		acpi_default_enumeration(adev);
2211 
2212 	return 1;
2213 }
2214 
2215 static struct acpi_scan_handler generic_device_handler = {
2216 	.ids = generic_device_ids,
2217 	.attach = acpi_generic_device_attach,
2218 };
2219 
2220 static int acpi_scan_attach_handler(struct acpi_device *device)
2221 {
2222 	struct acpi_hardware_id *hwid;
2223 	int ret = 0;
2224 
2225 	list_for_each_entry(hwid, &device->pnp.ids, list) {
2226 		const struct acpi_device_id *devid;
2227 		struct acpi_scan_handler *handler;
2228 
2229 		handler = acpi_scan_match_handler(hwid->id, &devid);
2230 		if (handler) {
2231 			if (!handler->attach) {
2232 				device->pnp.type.platform_id = 0;
2233 				continue;
2234 			}
2235 			device->handler = handler;
2236 			ret = handler->attach(device, devid);
2237 			if (ret > 0)
2238 				break;
2239 
2240 			device->handler = NULL;
2241 			if (ret < 0)
2242 				break;
2243 		}
2244 	}
2245 
2246 	return ret;
2247 }
2248 
2249 static int acpi_bus_attach(struct acpi_device *device, void *first_pass)
2250 {
2251 	bool skip = !first_pass && device->flags.visited;
2252 	acpi_handle ejd;
2253 	int ret;
2254 
2255 	if (skip)
2256 		goto ok;
2257 
2258 	if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
2259 		register_dock_dependent_device(device, ejd);
2260 
2261 	acpi_bus_get_status(device);
2262 	/* Skip devices that are not ready for enumeration (e.g. not present) */
2263 	if (!acpi_dev_ready_for_enumeration(device)) {
2264 		device->flags.initialized = false;
2265 		acpi_device_clear_enumerated(device);
2266 		device->flags.power_manageable = 0;
2267 		return 0;
2268 	}
2269 	if (device->handler)
2270 		goto ok;
2271 
2272 	if (!device->flags.initialized) {
2273 		device->flags.power_manageable =
2274 			device->power.states[ACPI_STATE_D0].flags.valid;
2275 		if (acpi_bus_init_power(device))
2276 			device->flags.power_manageable = 0;
2277 
2278 		device->flags.initialized = true;
2279 	} else if (device->flags.visited) {
2280 		goto ok;
2281 	}
2282 
2283 	ret = acpi_scan_attach_handler(device);
2284 	if (ret < 0)
2285 		return 0;
2286 
2287 	device->flags.match_driver = true;
2288 	if (ret > 0 && !device->flags.enumeration_by_parent) {
2289 		acpi_device_set_enumerated(device);
2290 		goto ok;
2291 	}
2292 
2293 	ret = device_attach(&device->dev);
2294 	if (ret < 0)
2295 		return 0;
2296 
2297 	if (device->pnp.type.platform_id || device->flags.enumeration_by_parent)
2298 		acpi_default_enumeration(device);
2299 	else
2300 		acpi_device_set_enumerated(device);
2301 
2302 ok:
2303 	acpi_dev_for_each_child(device, acpi_bus_attach, first_pass);
2304 
2305 	if (!skip && device->handler && device->handler->hotplug.notify_online)
2306 		device->handler->hotplug.notify_online(device);
2307 
2308 	return 0;
2309 }
2310 
2311 static int acpi_dev_get_next_consumer_dev_cb(struct acpi_dep_data *dep, void *data)
2312 {
2313 	struct acpi_device **adev_p = data;
2314 	struct acpi_device *adev = *adev_p;
2315 
2316 	/*
2317 	 * If we're passed a 'previous' consumer device then we need to skip
2318 	 * any consumers until we meet the previous one, and then NULL @data
2319 	 * so the next one can be returned.
2320 	 */
2321 	if (adev) {
2322 		if (dep->consumer == adev->handle)
2323 			*adev_p = NULL;
2324 
2325 		return 0;
2326 	}
2327 
2328 	adev = acpi_get_acpi_dev(dep->consumer);
2329 	if (adev) {
2330 		*(struct acpi_device **)data = adev;
2331 		return 1;
2332 	}
2333 	/* Continue parsing if the device object is not present. */
2334 	return 0;
2335 }
2336 
2337 struct acpi_scan_clear_dep_work {
2338 	struct work_struct work;
2339 	struct acpi_device *adev;
2340 };
2341 
2342 static void acpi_scan_clear_dep_fn(struct work_struct *work)
2343 {
2344 	struct acpi_scan_clear_dep_work *cdw;
2345 
2346 	cdw = container_of(work, struct acpi_scan_clear_dep_work, work);
2347 
2348 	acpi_scan_lock_acquire();
2349 	acpi_bus_attach(cdw->adev, (void *)true);
2350 	acpi_scan_lock_release();
2351 
2352 	acpi_dev_put(cdw->adev);
2353 	kfree(cdw);
2354 }
2355 
2356 static bool acpi_scan_clear_dep_queue(struct acpi_device *adev)
2357 {
2358 	struct acpi_scan_clear_dep_work *cdw;
2359 
2360 	if (adev->dep_unmet)
2361 		return false;
2362 
2363 	cdw = kmalloc(sizeof(*cdw), GFP_KERNEL);
2364 	if (!cdw)
2365 		return false;
2366 
2367 	cdw->adev = adev;
2368 	INIT_WORK(&cdw->work, acpi_scan_clear_dep_fn);
2369 	/*
2370 	 * Since the work function may block on the lock until the entire
2371 	 * initial enumeration of devices is complete, put it into the unbound
2372 	 * workqueue.
2373 	 */
2374 	queue_work(system_unbound_wq, &cdw->work);
2375 
2376 	return true;
2377 }
2378 
2379 static void acpi_scan_delete_dep_data(struct acpi_dep_data *dep)
2380 {
2381 	list_del(&dep->node);
2382 	kfree(dep);
2383 }
2384 
2385 static int acpi_scan_clear_dep(struct acpi_dep_data *dep, void *data)
2386 {
2387 	struct acpi_device *adev = acpi_get_acpi_dev(dep->consumer);
2388 
2389 	if (adev) {
2390 		adev->dep_unmet--;
2391 		if (!acpi_scan_clear_dep_queue(adev))
2392 			acpi_dev_put(adev);
2393 	}
2394 
2395 	if (dep->free_when_met)
2396 		acpi_scan_delete_dep_data(dep);
2397 	else
2398 		dep->met = true;
2399 
2400 	return 0;
2401 }
2402 
2403 /**
2404  * acpi_walk_dep_device_list - Apply a callback to every entry in acpi_dep_list
2405  * @handle:	The ACPI handle of the supplier device
2406  * @callback:	Pointer to the callback function to apply
2407  * @data:	Pointer to some data to pass to the callback
2408  *
2409  * The return value of the callback determines this function's behaviour. If 0
2410  * is returned we continue to iterate over acpi_dep_list. If a positive value
2411  * is returned then the loop is broken but this function returns 0. If a
2412  * negative value is returned by the callback then the loop is broken and that
2413  * value is returned as the final error.
2414  */
2415 static int acpi_walk_dep_device_list(acpi_handle handle,
2416 				int (*callback)(struct acpi_dep_data *, void *),
2417 				void *data)
2418 {
2419 	struct acpi_dep_data *dep, *tmp;
2420 	int ret = 0;
2421 
2422 	mutex_lock(&acpi_dep_list_lock);
2423 	list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
2424 		if (dep->supplier == handle) {
2425 			ret = callback(dep, data);
2426 			if (ret)
2427 				break;
2428 		}
2429 	}
2430 	mutex_unlock(&acpi_dep_list_lock);
2431 
2432 	return ret > 0 ? 0 : ret;
2433 }
2434 
2435 /**
2436  * acpi_dev_clear_dependencies - Inform consumers that the device is now active
2437  * @supplier: Pointer to the supplier &struct acpi_device
2438  *
2439  * Clear dependencies on the given device.
2440  */
2441 void acpi_dev_clear_dependencies(struct acpi_device *supplier)
2442 {
2443 	acpi_walk_dep_device_list(supplier->handle, acpi_scan_clear_dep, NULL);
2444 }
2445 EXPORT_SYMBOL_GPL(acpi_dev_clear_dependencies);
2446 
2447 /**
2448  * acpi_dev_ready_for_enumeration - Check if the ACPI device is ready for enumeration
2449  * @device: Pointer to the &struct acpi_device to check
2450  *
2451  * Check if the device is present and has no unmet dependencies.
2452  *
2453  * Return true if the device is ready for enumeratino. Otherwise, return false.
2454  */
2455 bool acpi_dev_ready_for_enumeration(const struct acpi_device *device)
2456 {
2457 	if (device->flags.honor_deps && device->dep_unmet)
2458 		return false;
2459 
2460 	return acpi_device_is_present(device);
2461 }
2462 EXPORT_SYMBOL_GPL(acpi_dev_ready_for_enumeration);
2463 
2464 /**
2465  * acpi_dev_get_next_consumer_dev - Return the next adev dependent on @supplier
2466  * @supplier: Pointer to the dependee device
2467  * @start: Pointer to the current dependent device
2468  *
2469  * Returns the next &struct acpi_device which declares itself dependent on
2470  * @supplier via the _DEP buffer, parsed from the acpi_dep_list.
2471  *
2472  * If the returned adev is not passed as @start to this function, the caller is
2473  * responsible for putting the reference to adev when it is no longer needed.
2474  */
2475 struct acpi_device *acpi_dev_get_next_consumer_dev(struct acpi_device *supplier,
2476 						   struct acpi_device *start)
2477 {
2478 	struct acpi_device *adev = start;
2479 
2480 	acpi_walk_dep_device_list(supplier->handle,
2481 				  acpi_dev_get_next_consumer_dev_cb, &adev);
2482 
2483 	acpi_dev_put(start);
2484 
2485 	if (adev == start)
2486 		return NULL;
2487 
2488 	return adev;
2489 }
2490 EXPORT_SYMBOL_GPL(acpi_dev_get_next_consumer_dev);
2491 
2492 static void acpi_scan_postponed_branch(acpi_handle handle)
2493 {
2494 	struct acpi_device *adev = NULL;
2495 
2496 	if (ACPI_FAILURE(acpi_bus_check_add(handle, false, &adev)))
2497 		return;
2498 
2499 	acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2500 			    acpi_bus_check_add_2, NULL, NULL, (void **)&adev);
2501 
2502 	/*
2503 	 * Populate the ACPI _CRS CSI-2 software nodes for the ACPI devices that
2504 	 * have been added above.
2505 	 */
2506 	acpi_mipi_init_crs_csi2_swnodes();
2507 
2508 	acpi_bus_attach(adev, NULL);
2509 }
2510 
2511 static void acpi_scan_postponed(void)
2512 {
2513 	struct acpi_dep_data *dep, *tmp;
2514 
2515 	mutex_lock(&acpi_dep_list_lock);
2516 
2517 	list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
2518 		acpi_handle handle = dep->consumer;
2519 
2520 		/*
2521 		 * In case there are multiple acpi_dep_list entries with the
2522 		 * same consumer, skip the current entry if the consumer device
2523 		 * object corresponding to it is present already.
2524 		 */
2525 		if (!acpi_fetch_acpi_dev(handle)) {
2526 			/*
2527 			 * Even though the lock is released here, tmp is
2528 			 * guaranteed to be valid, because none of the list
2529 			 * entries following dep is marked as "free when met"
2530 			 * and so they cannot be deleted.
2531 			 */
2532 			mutex_unlock(&acpi_dep_list_lock);
2533 
2534 			acpi_scan_postponed_branch(handle);
2535 
2536 			mutex_lock(&acpi_dep_list_lock);
2537 		}
2538 
2539 		if (dep->met)
2540 			acpi_scan_delete_dep_data(dep);
2541 		else
2542 			dep->free_when_met = true;
2543 	}
2544 
2545 	mutex_unlock(&acpi_dep_list_lock);
2546 }
2547 
2548 /**
2549  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
2550  * @handle: Root of the namespace scope to scan.
2551  *
2552  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
2553  * found devices.
2554  *
2555  * If no devices were found, -ENODEV is returned, but it does not mean that
2556  * there has been a real error.  There just have been no suitable ACPI objects
2557  * in the table trunk from which the kernel could create a device and add an
2558  * appropriate driver.
2559  *
2560  * Must be called under acpi_scan_lock.
2561  */
2562 int acpi_bus_scan(acpi_handle handle)
2563 {
2564 	struct acpi_device *device = NULL;
2565 
2566 	/* Pass 1: Avoid enumerating devices with missing dependencies. */
2567 
2568 	if (ACPI_SUCCESS(acpi_bus_check_add(handle, true, &device)))
2569 		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2570 				    acpi_bus_check_add_1, NULL, NULL,
2571 				    (void **)&device);
2572 
2573 	if (!device)
2574 		return -ENODEV;
2575 
2576 	/*
2577 	 * Set up ACPI _CRS CSI-2 software nodes using information extracted
2578 	 * from the _CRS CSI-2 resource descriptors during the ACPI namespace
2579 	 * walk above and MIPI DisCo for Imaging device properties.
2580 	 */
2581 	acpi_mipi_scan_crs_csi2();
2582 	acpi_mipi_init_crs_csi2_swnodes();
2583 
2584 	acpi_bus_attach(device, (void *)true);
2585 
2586 	/* Pass 2: Enumerate all of the remaining devices. */
2587 
2588 	acpi_scan_postponed();
2589 
2590 	acpi_mipi_crs_csi2_cleanup();
2591 
2592 	return 0;
2593 }
2594 EXPORT_SYMBOL(acpi_bus_scan);
2595 
2596 /**
2597  * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
2598  * @adev: Root of the ACPI namespace scope to walk.
2599  *
2600  * Must be called under acpi_scan_lock.
2601  */
2602 void acpi_bus_trim(struct acpi_device *adev)
2603 {
2604 	acpi_scan_check_and_detach(adev, NULL);
2605 }
2606 EXPORT_SYMBOL_GPL(acpi_bus_trim);
2607 
2608 int acpi_bus_register_early_device(int type)
2609 {
2610 	struct acpi_device *device = NULL;
2611 	int result;
2612 
2613 	result = acpi_add_single_object(&device, NULL, type, false);
2614 	if (result)
2615 		return result;
2616 
2617 	device->flags.match_driver = true;
2618 	return device_attach(&device->dev);
2619 }
2620 EXPORT_SYMBOL_GPL(acpi_bus_register_early_device);
2621 
2622 static void acpi_bus_scan_fixed(void)
2623 {
2624 	if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2625 		struct acpi_device *adev = NULL;
2626 
2627 		acpi_add_single_object(&adev, NULL, ACPI_BUS_TYPE_POWER_BUTTON,
2628 				       false);
2629 		if (adev) {
2630 			adev->flags.match_driver = true;
2631 			if (device_attach(&adev->dev) >= 0)
2632 				device_init_wakeup(&adev->dev, true);
2633 			else
2634 				dev_dbg(&adev->dev, "No driver\n");
2635 		}
2636 	}
2637 
2638 	if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2639 		struct acpi_device *adev = NULL;
2640 
2641 		acpi_add_single_object(&adev, NULL, ACPI_BUS_TYPE_SLEEP_BUTTON,
2642 				       false);
2643 		if (adev) {
2644 			adev->flags.match_driver = true;
2645 			if (device_attach(&adev->dev) < 0)
2646 				dev_dbg(&adev->dev, "No driver\n");
2647 		}
2648 	}
2649 }
2650 
2651 static void __init acpi_get_spcr_uart_addr(void)
2652 {
2653 	acpi_status status;
2654 	struct acpi_table_spcr *spcr_ptr;
2655 
2656 	status = acpi_get_table(ACPI_SIG_SPCR, 0,
2657 				(struct acpi_table_header **)&spcr_ptr);
2658 	if (ACPI_FAILURE(status)) {
2659 		pr_warn("STAO table present, but SPCR is missing\n");
2660 		return;
2661 	}
2662 
2663 	spcr_uart_addr = spcr_ptr->serial_port.address;
2664 	acpi_put_table((struct acpi_table_header *)spcr_ptr);
2665 }
2666 
2667 static bool acpi_scan_initialized;
2668 
2669 void __init acpi_scan_init(void)
2670 {
2671 	acpi_status status;
2672 	struct acpi_table_stao *stao_ptr;
2673 
2674 	acpi_pci_root_init();
2675 	acpi_pci_link_init();
2676 	acpi_processor_init();
2677 	acpi_platform_init();
2678 	acpi_lpss_init();
2679 	acpi_apd_init();
2680 	acpi_cmos_rtc_init();
2681 	acpi_container_init();
2682 	acpi_memory_hotplug_init();
2683 	acpi_watchdog_init();
2684 	acpi_pnp_init();
2685 	acpi_int340x_thermal_init();
2686 	acpi_init_lpit();
2687 
2688 	acpi_scan_add_handler(&generic_device_handler);
2689 
2690 	/*
2691 	 * If there is STAO table, check whether it needs to ignore the UART
2692 	 * device in SPCR table.
2693 	 */
2694 	status = acpi_get_table(ACPI_SIG_STAO, 0,
2695 				(struct acpi_table_header **)&stao_ptr);
2696 	if (ACPI_SUCCESS(status)) {
2697 		if (stao_ptr->header.length > sizeof(struct acpi_table_stao))
2698 			pr_info("STAO Name List not yet supported.\n");
2699 
2700 		if (stao_ptr->ignore_uart)
2701 			acpi_get_spcr_uart_addr();
2702 
2703 		acpi_put_table((struct acpi_table_header *)stao_ptr);
2704 	}
2705 
2706 	acpi_gpe_apply_masked_gpes();
2707 	acpi_update_all_gpes();
2708 
2709 	/*
2710 	 * Although we call __add_memory() that is documented to require the
2711 	 * device_hotplug_lock, it is not necessary here because this is an
2712 	 * early code when userspace or any other code path cannot trigger
2713 	 * hotplug/hotunplug operations.
2714 	 */
2715 	mutex_lock(&acpi_scan_lock);
2716 	/*
2717 	 * Enumerate devices in the ACPI namespace.
2718 	 */
2719 	if (acpi_bus_scan(ACPI_ROOT_OBJECT))
2720 		goto unlock;
2721 
2722 	acpi_root = acpi_fetch_acpi_dev(ACPI_ROOT_OBJECT);
2723 	if (!acpi_root)
2724 		goto unlock;
2725 
2726 	/* Fixed feature devices do not exist on HW-reduced platform */
2727 	if (!acpi_gbl_reduced_hardware)
2728 		acpi_bus_scan_fixed();
2729 
2730 	acpi_turn_off_unused_power_resources();
2731 
2732 	acpi_scan_initialized = true;
2733 
2734 unlock:
2735 	mutex_unlock(&acpi_scan_lock);
2736 }
2737 
2738 static struct acpi_probe_entry *ape;
2739 static int acpi_probe_count;
2740 static DEFINE_MUTEX(acpi_probe_mutex);
2741 
2742 static int __init acpi_match_madt(union acpi_subtable_headers *header,
2743 				  const unsigned long end)
2744 {
2745 	if (!ape->subtable_valid || ape->subtable_valid(&header->common, ape))
2746 		if (!ape->probe_subtbl(header, end))
2747 			acpi_probe_count++;
2748 
2749 	return 0;
2750 }
2751 
2752 int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr)
2753 {
2754 	int count = 0;
2755 
2756 	if (acpi_disabled)
2757 		return 0;
2758 
2759 	mutex_lock(&acpi_probe_mutex);
2760 	for (ape = ap_head; nr; ape++, nr--) {
2761 		if (ACPI_COMPARE_NAMESEG(ACPI_SIG_MADT, ape->id)) {
2762 			acpi_probe_count = 0;
2763 			acpi_table_parse_madt(ape->type, acpi_match_madt, 0);
2764 			count += acpi_probe_count;
2765 		} else {
2766 			int res;
2767 			res = acpi_table_parse(ape->id, ape->probe_table);
2768 			if (!res)
2769 				count++;
2770 		}
2771 	}
2772 	mutex_unlock(&acpi_probe_mutex);
2773 
2774 	return count;
2775 }
2776 
2777 static void acpi_table_events_fn(struct work_struct *work)
2778 {
2779 	acpi_scan_lock_acquire();
2780 	acpi_bus_scan(ACPI_ROOT_OBJECT);
2781 	acpi_scan_lock_release();
2782 
2783 	kfree(work);
2784 }
2785 
2786 void acpi_scan_table_notify(void)
2787 {
2788 	struct work_struct *work;
2789 
2790 	if (!acpi_scan_initialized)
2791 		return;
2792 
2793 	work = kmalloc(sizeof(*work), GFP_KERNEL);
2794 	if (!work)
2795 		return;
2796 
2797 	INIT_WORK(work, acpi_table_events_fn);
2798 	schedule_work(work);
2799 }
2800 
2801 int acpi_reconfig_notifier_register(struct notifier_block *nb)
2802 {
2803 	return blocking_notifier_chain_register(&acpi_reconfig_chain, nb);
2804 }
2805 EXPORT_SYMBOL(acpi_reconfig_notifier_register);
2806 
2807 int acpi_reconfig_notifier_unregister(struct notifier_block *nb)
2808 {
2809 	return blocking_notifier_chain_unregister(&acpi_reconfig_chain, nb);
2810 }
2811 EXPORT_SYMBOL(acpi_reconfig_notifier_unregister);
2812