xref: /openbmc/linux/drivers/acpi/scan.c (revision ed84ef1c)
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 
23 #include "internal.h"
24 
25 extern struct acpi_device *acpi_root;
26 
27 #define ACPI_BUS_CLASS			"system_bus"
28 #define ACPI_BUS_HID			"LNXSYBUS"
29 #define ACPI_BUS_DEVICE_NAME		"System Bus"
30 
31 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
32 
33 #define INVALID_ACPI_HANDLE	((acpi_handle)empty_zero_page)
34 
35 static const char *dummy_hid = "device";
36 
37 static LIST_HEAD(acpi_dep_list);
38 static DEFINE_MUTEX(acpi_dep_list_lock);
39 LIST_HEAD(acpi_bus_id_list);
40 static DEFINE_MUTEX(acpi_scan_lock);
41 static LIST_HEAD(acpi_scan_handlers_list);
42 DEFINE_MUTEX(acpi_device_lock);
43 LIST_HEAD(acpi_wakeup_device_list);
44 static DEFINE_MUTEX(acpi_hp_context_lock);
45 
46 /*
47  * The UART device described by the SPCR table is the only object which needs
48  * special-casing. Everything else is covered by ACPI namespace paths in STAO
49  * table.
50  */
51 static u64 spcr_uart_addr;
52 
53 void acpi_scan_lock_acquire(void)
54 {
55 	mutex_lock(&acpi_scan_lock);
56 }
57 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
58 
59 void acpi_scan_lock_release(void)
60 {
61 	mutex_unlock(&acpi_scan_lock);
62 }
63 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
64 
65 void acpi_lock_hp_context(void)
66 {
67 	mutex_lock(&acpi_hp_context_lock);
68 }
69 
70 void acpi_unlock_hp_context(void)
71 {
72 	mutex_unlock(&acpi_hp_context_lock);
73 }
74 
75 void acpi_initialize_hp_context(struct acpi_device *adev,
76 				struct acpi_hotplug_context *hp,
77 				int (*notify)(struct acpi_device *, u32),
78 				void (*uevent)(struct acpi_device *, u32))
79 {
80 	acpi_lock_hp_context();
81 	hp->notify = notify;
82 	hp->uevent = uevent;
83 	acpi_set_hp_context(adev, hp);
84 	acpi_unlock_hp_context();
85 }
86 EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
87 
88 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
89 {
90 	if (!handler)
91 		return -EINVAL;
92 
93 	list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
94 	return 0;
95 }
96 
97 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
98 				       const char *hotplug_profile_name)
99 {
100 	int error;
101 
102 	error = acpi_scan_add_handler(handler);
103 	if (error)
104 		return error;
105 
106 	acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
107 	return 0;
108 }
109 
110 bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
111 {
112 	struct acpi_device_physical_node *pn;
113 	bool offline = true;
114 	char *envp[] = { "EVENT=offline", NULL };
115 
116 	/*
117 	 * acpi_container_offline() calls this for all of the container's
118 	 * children under the container's physical_node_lock lock.
119 	 */
120 	mutex_lock_nested(&adev->physical_node_lock, SINGLE_DEPTH_NESTING);
121 
122 	list_for_each_entry(pn, &adev->physical_node_list, node)
123 		if (device_supports_offline(pn->dev) && !pn->dev->offline) {
124 			if (uevent)
125 				kobject_uevent_env(&pn->dev->kobj, KOBJ_CHANGE, envp);
126 
127 			offline = false;
128 			break;
129 		}
130 
131 	mutex_unlock(&adev->physical_node_lock);
132 	return offline;
133 }
134 
135 static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
136 				    void **ret_p)
137 {
138 	struct acpi_device *device = NULL;
139 	struct acpi_device_physical_node *pn;
140 	bool second_pass = (bool)data;
141 	acpi_status status = AE_OK;
142 
143 	if (acpi_bus_get_device(handle, &device))
144 		return AE_OK;
145 
146 	if (device->handler && !device->handler->hotplug.enabled) {
147 		*ret_p = &device->dev;
148 		return AE_SUPPORT;
149 	}
150 
151 	mutex_lock(&device->physical_node_lock);
152 
153 	list_for_each_entry(pn, &device->physical_node_list, node) {
154 		int ret;
155 
156 		if (second_pass) {
157 			/* Skip devices offlined by the first pass. */
158 			if (pn->put_online)
159 				continue;
160 		} else {
161 			pn->put_online = false;
162 		}
163 		ret = device_offline(pn->dev);
164 		if (ret >= 0) {
165 			pn->put_online = !ret;
166 		} else {
167 			*ret_p = pn->dev;
168 			if (second_pass) {
169 				status = AE_ERROR;
170 				break;
171 			}
172 		}
173 	}
174 
175 	mutex_unlock(&device->physical_node_lock);
176 
177 	return status;
178 }
179 
180 static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
181 				   void **ret_p)
182 {
183 	struct acpi_device *device = NULL;
184 	struct acpi_device_physical_node *pn;
185 
186 	if (acpi_bus_get_device(handle, &device))
187 		return AE_OK;
188 
189 	mutex_lock(&device->physical_node_lock);
190 
191 	list_for_each_entry(pn, &device->physical_node_list, node)
192 		if (pn->put_online) {
193 			device_online(pn->dev);
194 			pn->put_online = false;
195 		}
196 
197 	mutex_unlock(&device->physical_node_lock);
198 
199 	return AE_OK;
200 }
201 
202 static int acpi_scan_try_to_offline(struct acpi_device *device)
203 {
204 	acpi_handle handle = device->handle;
205 	struct device *errdev = NULL;
206 	acpi_status status;
207 
208 	/*
209 	 * Carry out two passes here and ignore errors in the first pass,
210 	 * because if the devices in question are memory blocks and
211 	 * CONFIG_MEMCG is set, one of the blocks may hold data structures
212 	 * that the other blocks depend on, but it is not known in advance which
213 	 * block holds them.
214 	 *
215 	 * If the first pass is successful, the second one isn't needed, though.
216 	 */
217 	status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
218 				     NULL, acpi_bus_offline, (void *)false,
219 				     (void **)&errdev);
220 	if (status == AE_SUPPORT) {
221 		dev_warn(errdev, "Offline disabled.\n");
222 		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
223 				    acpi_bus_online, NULL, NULL, NULL);
224 		return -EPERM;
225 	}
226 	acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
227 	if (errdev) {
228 		errdev = NULL;
229 		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
230 				    NULL, acpi_bus_offline, (void *)true,
231 				    (void **)&errdev);
232 		if (!errdev)
233 			acpi_bus_offline(handle, 0, (void *)true,
234 					 (void **)&errdev);
235 
236 		if (errdev) {
237 			dev_warn(errdev, "Offline failed.\n");
238 			acpi_bus_online(handle, 0, NULL, NULL);
239 			acpi_walk_namespace(ACPI_TYPE_ANY, handle,
240 					    ACPI_UINT32_MAX, acpi_bus_online,
241 					    NULL, NULL, NULL);
242 			return -EBUSY;
243 		}
244 	}
245 	return 0;
246 }
247 
248 static int acpi_scan_hot_remove(struct acpi_device *device)
249 {
250 	acpi_handle handle = device->handle;
251 	unsigned long long sta;
252 	acpi_status status;
253 
254 	if (device->handler && device->handler->hotplug.demand_offline) {
255 		if (!acpi_scan_is_offline(device, true))
256 			return -EBUSY;
257 	} else {
258 		int error = acpi_scan_try_to_offline(device);
259 		if (error)
260 			return error;
261 	}
262 
263 	acpi_handle_debug(handle, "Ejecting\n");
264 
265 	acpi_bus_trim(device);
266 
267 	acpi_evaluate_lck(handle, 0);
268 	/*
269 	 * TBD: _EJD support.
270 	 */
271 	status = acpi_evaluate_ej0(handle);
272 	if (status == AE_NOT_FOUND)
273 		return -ENODEV;
274 	else if (ACPI_FAILURE(status))
275 		return -EIO;
276 
277 	/*
278 	 * Verify if eject was indeed successful.  If not, log an error
279 	 * message.  No need to call _OST since _EJ0 call was made OK.
280 	 */
281 	status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
282 	if (ACPI_FAILURE(status)) {
283 		acpi_handle_warn(handle,
284 			"Status check after eject failed (0x%x)\n", status);
285 	} else if (sta & ACPI_STA_DEVICE_ENABLED) {
286 		acpi_handle_warn(handle,
287 			"Eject incomplete - status 0x%llx\n", sta);
288 	}
289 
290 	return 0;
291 }
292 
293 static int acpi_scan_device_not_present(struct acpi_device *adev)
294 {
295 	if (!acpi_device_enumerated(adev)) {
296 		dev_warn(&adev->dev, "Still not present\n");
297 		return -EALREADY;
298 	}
299 	acpi_bus_trim(adev);
300 	return 0;
301 }
302 
303 static int acpi_scan_device_check(struct acpi_device *adev)
304 {
305 	int error;
306 
307 	acpi_bus_get_status(adev);
308 	if (adev->status.present || adev->status.functional) {
309 		/*
310 		 * This function is only called for device objects for which
311 		 * matching scan handlers exist.  The only situation in which
312 		 * the scan handler is not attached to this device object yet
313 		 * is when the device has just appeared (either it wasn't
314 		 * present at all before or it was removed and then added
315 		 * again).
316 		 */
317 		if (adev->handler) {
318 			dev_warn(&adev->dev, "Already enumerated\n");
319 			return -EALREADY;
320 		}
321 		error = acpi_bus_scan(adev->handle);
322 		if (error) {
323 			dev_warn(&adev->dev, "Namespace scan failure\n");
324 			return error;
325 		}
326 		if (!adev->handler) {
327 			dev_warn(&adev->dev, "Enumeration failure\n");
328 			error = -ENODEV;
329 		}
330 	} else {
331 		error = acpi_scan_device_not_present(adev);
332 	}
333 	return error;
334 }
335 
336 static int acpi_scan_bus_check(struct acpi_device *adev)
337 {
338 	struct acpi_scan_handler *handler = adev->handler;
339 	struct acpi_device *child;
340 	int error;
341 
342 	acpi_bus_get_status(adev);
343 	if (!(adev->status.present || adev->status.functional)) {
344 		acpi_scan_device_not_present(adev);
345 		return 0;
346 	}
347 	if (handler && handler->hotplug.scan_dependent)
348 		return handler->hotplug.scan_dependent(adev);
349 
350 	error = acpi_bus_scan(adev->handle);
351 	if (error) {
352 		dev_warn(&adev->dev, "Namespace scan failure\n");
353 		return error;
354 	}
355 	list_for_each_entry(child, &adev->children, node) {
356 		error = acpi_scan_bus_check(child);
357 		if (error)
358 			return error;
359 	}
360 	return 0;
361 }
362 
363 static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type)
364 {
365 	switch (type) {
366 	case ACPI_NOTIFY_BUS_CHECK:
367 		return acpi_scan_bus_check(adev);
368 	case ACPI_NOTIFY_DEVICE_CHECK:
369 		return acpi_scan_device_check(adev);
370 	case ACPI_NOTIFY_EJECT_REQUEST:
371 	case ACPI_OST_EC_OSPM_EJECT:
372 		if (adev->handler && !adev->handler->hotplug.enabled) {
373 			dev_info(&adev->dev, "Eject disabled\n");
374 			return -EPERM;
375 		}
376 		acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST,
377 				  ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
378 		return acpi_scan_hot_remove(adev);
379 	}
380 	return -EINVAL;
381 }
382 
383 void acpi_device_hotplug(struct acpi_device *adev, u32 src)
384 {
385 	u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
386 	int error = -ENODEV;
387 
388 	lock_device_hotplug();
389 	mutex_lock(&acpi_scan_lock);
390 
391 	/*
392 	 * The device object's ACPI handle cannot become invalid as long as we
393 	 * are holding acpi_scan_lock, but it might have become invalid before
394 	 * that lock was acquired.
395 	 */
396 	if (adev->handle == INVALID_ACPI_HANDLE)
397 		goto err_out;
398 
399 	if (adev->flags.is_dock_station) {
400 		error = dock_notify(adev, src);
401 	} else if (adev->flags.hotplug_notify) {
402 		error = acpi_generic_hotplug_event(adev, src);
403 	} else {
404 		int (*notify)(struct acpi_device *, u32);
405 
406 		acpi_lock_hp_context();
407 		notify = adev->hp ? adev->hp->notify : NULL;
408 		acpi_unlock_hp_context();
409 		/*
410 		 * There may be additional notify handlers for device objects
411 		 * without the .event() callback, so ignore them here.
412 		 */
413 		if (notify)
414 			error = notify(adev, src);
415 		else
416 			goto out;
417 	}
418 	switch (error) {
419 	case 0:
420 		ost_code = ACPI_OST_SC_SUCCESS;
421 		break;
422 	case -EPERM:
423 		ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
424 		break;
425 	case -EBUSY:
426 		ost_code = ACPI_OST_SC_DEVICE_BUSY;
427 		break;
428 	default:
429 		ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
430 		break;
431 	}
432 
433  err_out:
434 	acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
435 
436  out:
437 	acpi_bus_put_acpi_device(adev);
438 	mutex_unlock(&acpi_scan_lock);
439 	unlock_device_hotplug();
440 }
441 
442 static void acpi_free_power_resources_lists(struct acpi_device *device)
443 {
444 	int i;
445 
446 	if (device->wakeup.flags.valid)
447 		acpi_power_resources_list_free(&device->wakeup.resources);
448 
449 	if (!device->power.flags.power_resources)
450 		return;
451 
452 	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
453 		struct acpi_device_power_state *ps = &device->power.states[i];
454 		acpi_power_resources_list_free(&ps->resources);
455 	}
456 }
457 
458 static void acpi_device_release(struct device *dev)
459 {
460 	struct acpi_device *acpi_dev = to_acpi_device(dev);
461 
462 	acpi_free_properties(acpi_dev);
463 	acpi_free_pnp_ids(&acpi_dev->pnp);
464 	acpi_free_power_resources_lists(acpi_dev);
465 	kfree(acpi_dev);
466 }
467 
468 static void acpi_device_del(struct acpi_device *device)
469 {
470 	struct acpi_device_bus_id *acpi_device_bus_id;
471 
472 	mutex_lock(&acpi_device_lock);
473 	if (device->parent)
474 		list_del(&device->node);
475 
476 	list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node)
477 		if (!strcmp(acpi_device_bus_id->bus_id,
478 			    acpi_device_hid(device))) {
479 			ida_simple_remove(&acpi_device_bus_id->instance_ida, device->pnp.instance_no);
480 			if (ida_is_empty(&acpi_device_bus_id->instance_ida)) {
481 				list_del(&acpi_device_bus_id->node);
482 				kfree_const(acpi_device_bus_id->bus_id);
483 				kfree(acpi_device_bus_id);
484 			}
485 			break;
486 		}
487 
488 	list_del(&device->wakeup_list);
489 	mutex_unlock(&acpi_device_lock);
490 
491 	acpi_power_add_remove_device(device, false);
492 	acpi_device_remove_files(device);
493 	if (device->remove)
494 		device->remove(device);
495 
496 	device_del(&device->dev);
497 }
498 
499 static BLOCKING_NOTIFIER_HEAD(acpi_reconfig_chain);
500 
501 static LIST_HEAD(acpi_device_del_list);
502 static DEFINE_MUTEX(acpi_device_del_lock);
503 
504 static void acpi_device_del_work_fn(struct work_struct *work_not_used)
505 {
506 	for (;;) {
507 		struct acpi_device *adev;
508 
509 		mutex_lock(&acpi_device_del_lock);
510 
511 		if (list_empty(&acpi_device_del_list)) {
512 			mutex_unlock(&acpi_device_del_lock);
513 			break;
514 		}
515 		adev = list_first_entry(&acpi_device_del_list,
516 					struct acpi_device, del_list);
517 		list_del(&adev->del_list);
518 
519 		mutex_unlock(&acpi_device_del_lock);
520 
521 		blocking_notifier_call_chain(&acpi_reconfig_chain,
522 					     ACPI_RECONFIG_DEVICE_REMOVE, adev);
523 
524 		acpi_device_del(adev);
525 		/*
526 		 * Drop references to all power resources that might have been
527 		 * used by the device.
528 		 */
529 		acpi_power_transition(adev, ACPI_STATE_D3_COLD);
530 		acpi_dev_put(adev);
531 	}
532 }
533 
534 /**
535  * acpi_scan_drop_device - Drop an ACPI device object.
536  * @handle: Handle of an ACPI namespace node, not used.
537  * @context: Address of the ACPI device object to drop.
538  *
539  * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
540  * namespace node the device object pointed to by @context is attached to.
541  *
542  * The unregistration is carried out asynchronously to avoid running
543  * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
544  * ensure the correct ordering (the device objects must be unregistered in the
545  * same order in which the corresponding namespace nodes are deleted).
546  */
547 static void acpi_scan_drop_device(acpi_handle handle, void *context)
548 {
549 	static DECLARE_WORK(work, acpi_device_del_work_fn);
550 	struct acpi_device *adev = context;
551 
552 	mutex_lock(&acpi_device_del_lock);
553 
554 	/*
555 	 * Use the ACPI hotplug workqueue which is ordered, so this work item
556 	 * won't run after any hotplug work items submitted subsequently.  That
557 	 * prevents attempts to register device objects identical to those being
558 	 * deleted from happening concurrently (such attempts result from
559 	 * hotplug events handled via the ACPI hotplug workqueue).  It also will
560 	 * run after all of the work items submitted previously, which helps
561 	 * those work items to ensure that they are not accessing stale device
562 	 * objects.
563 	 */
564 	if (list_empty(&acpi_device_del_list))
565 		acpi_queue_hotplug_work(&work);
566 
567 	list_add_tail(&adev->del_list, &acpi_device_del_list);
568 	/* Make acpi_ns_validate_handle() return NULL for this handle. */
569 	adev->handle = INVALID_ACPI_HANDLE;
570 
571 	mutex_unlock(&acpi_device_del_lock);
572 }
573 
574 static struct acpi_device *handle_to_device(acpi_handle handle,
575 					    void (*callback)(void *))
576 {
577 	struct acpi_device *adev = NULL;
578 	acpi_status status;
579 
580 	status = acpi_get_data_full(handle, acpi_scan_drop_device,
581 				    (void **)&adev, callback);
582 	if (ACPI_FAILURE(status) || !adev) {
583 		acpi_handle_debug(handle, "No context!\n");
584 		return NULL;
585 	}
586 	return adev;
587 }
588 
589 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
590 {
591 	if (!device)
592 		return -EINVAL;
593 
594 	*device = handle_to_device(handle, NULL);
595 	if (!*device)
596 		return -ENODEV;
597 
598 	return 0;
599 }
600 EXPORT_SYMBOL(acpi_bus_get_device);
601 
602 static void get_acpi_device(void *dev)
603 {
604 	acpi_dev_get(dev);
605 }
606 
607 struct acpi_device *acpi_bus_get_acpi_device(acpi_handle handle)
608 {
609 	return handle_to_device(handle, get_acpi_device);
610 }
611 
612 static struct acpi_device_bus_id *acpi_device_bus_id_match(const char *dev_id)
613 {
614 	struct acpi_device_bus_id *acpi_device_bus_id;
615 
616 	/* Find suitable bus_id and instance number in acpi_bus_id_list. */
617 	list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
618 		if (!strcmp(acpi_device_bus_id->bus_id, dev_id))
619 			return acpi_device_bus_id;
620 	}
621 	return NULL;
622 }
623 
624 static int acpi_device_set_name(struct acpi_device *device,
625 				struct acpi_device_bus_id *acpi_device_bus_id)
626 {
627 	struct ida *instance_ida = &acpi_device_bus_id->instance_ida;
628 	int result;
629 
630 	result = ida_simple_get(instance_ida, 0, ACPI_MAX_DEVICE_INSTANCES, GFP_KERNEL);
631 	if (result < 0)
632 		return result;
633 
634 	device->pnp.instance_no = result;
635 	dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, result);
636 	return 0;
637 }
638 
639 static int acpi_tie_acpi_dev(struct acpi_device *adev)
640 {
641 	acpi_handle handle = adev->handle;
642 	acpi_status status;
643 
644 	if (!handle)
645 		return 0;
646 
647 	status = acpi_attach_data(handle, acpi_scan_drop_device, adev);
648 	if (ACPI_FAILURE(status)) {
649 		acpi_handle_err(handle, "Unable to attach device data\n");
650 		return -ENODEV;
651 	}
652 
653 	return 0;
654 }
655 
656 static int __acpi_device_add(struct acpi_device *device,
657 			     void (*release)(struct device *))
658 {
659 	struct acpi_device_bus_id *acpi_device_bus_id;
660 	int result;
661 
662 	/*
663 	 * Linkage
664 	 * -------
665 	 * Link this device to its parent and siblings.
666 	 */
667 	INIT_LIST_HEAD(&device->children);
668 	INIT_LIST_HEAD(&device->node);
669 	INIT_LIST_HEAD(&device->wakeup_list);
670 	INIT_LIST_HEAD(&device->physical_node_list);
671 	INIT_LIST_HEAD(&device->del_list);
672 	mutex_init(&device->physical_node_lock);
673 
674 	mutex_lock(&acpi_device_lock);
675 
676 	acpi_device_bus_id = acpi_device_bus_id_match(acpi_device_hid(device));
677 	if (acpi_device_bus_id) {
678 		result = acpi_device_set_name(device, acpi_device_bus_id);
679 		if (result)
680 			goto err_unlock;
681 	} else {
682 		acpi_device_bus_id = kzalloc(sizeof(*acpi_device_bus_id),
683 					     GFP_KERNEL);
684 		if (!acpi_device_bus_id) {
685 			result = -ENOMEM;
686 			goto err_unlock;
687 		}
688 		acpi_device_bus_id->bus_id =
689 			kstrdup_const(acpi_device_hid(device), GFP_KERNEL);
690 		if (!acpi_device_bus_id->bus_id) {
691 			kfree(acpi_device_bus_id);
692 			result = -ENOMEM;
693 			goto err_unlock;
694 		}
695 
696 		ida_init(&acpi_device_bus_id->instance_ida);
697 
698 		result = acpi_device_set_name(device, acpi_device_bus_id);
699 		if (result) {
700 			kfree_const(acpi_device_bus_id->bus_id);
701 			kfree(acpi_device_bus_id);
702 			goto err_unlock;
703 		}
704 
705 		list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
706 	}
707 
708 	if (device->parent)
709 		list_add_tail(&device->node, &device->parent->children);
710 
711 	if (device->wakeup.flags.valid)
712 		list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
713 
714 	mutex_unlock(&acpi_device_lock);
715 
716 	if (device->parent)
717 		device->dev.parent = &device->parent->dev;
718 
719 	device->dev.bus = &acpi_bus_type;
720 	device->dev.release = release;
721 	result = device_add(&device->dev);
722 	if (result) {
723 		dev_err(&device->dev, "Error registering device\n");
724 		goto err;
725 	}
726 
727 	result = acpi_device_setup_files(device);
728 	if (result)
729 		pr_err("Error creating sysfs interface for device %s\n",
730 		       dev_name(&device->dev));
731 
732 	return 0;
733 
734 err:
735 	mutex_lock(&acpi_device_lock);
736 
737 	if (device->parent)
738 		list_del(&device->node);
739 
740 	list_del(&device->wakeup_list);
741 
742 err_unlock:
743 	mutex_unlock(&acpi_device_lock);
744 
745 	acpi_detach_data(device->handle, acpi_scan_drop_device);
746 
747 	return result;
748 }
749 
750 int acpi_device_add(struct acpi_device *adev, void (*release)(struct device *))
751 {
752 	int ret;
753 
754 	ret = acpi_tie_acpi_dev(adev);
755 	if (ret)
756 		return ret;
757 
758 	return __acpi_device_add(adev, release);
759 }
760 
761 /* --------------------------------------------------------------------------
762                                  Device Enumeration
763    -------------------------------------------------------------------------- */
764 static bool acpi_info_matches_ids(struct acpi_device_info *info,
765 				  const char * const ids[])
766 {
767 	struct acpi_pnp_device_id_list *cid_list = NULL;
768 	int i, index;
769 
770 	if (!(info->valid & ACPI_VALID_HID))
771 		return false;
772 
773 	index = match_string(ids, -1, info->hardware_id.string);
774 	if (index >= 0)
775 		return true;
776 
777 	if (info->valid & ACPI_VALID_CID)
778 		cid_list = &info->compatible_id_list;
779 
780 	if (!cid_list)
781 		return false;
782 
783 	for (i = 0; i < cid_list->count; i++) {
784 		index = match_string(ids, -1, cid_list->ids[i].string);
785 		if (index >= 0)
786 			return true;
787 	}
788 
789 	return false;
790 }
791 
792 /* List of HIDs for which we ignore matching ACPI devices, when checking _DEP lists. */
793 static const char * const acpi_ignore_dep_ids[] = {
794 	"PNP0D80", /* Windows-compatible System Power Management Controller */
795 	"INT33BD", /* Intel Baytrail Mailbox Device */
796 	NULL
797 };
798 
799 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
800 {
801 	struct acpi_device *device = NULL;
802 	acpi_status status;
803 
804 	/*
805 	 * Fixed hardware devices do not appear in the namespace and do not
806 	 * have handles, but we fabricate acpi_devices for them, so we have
807 	 * to deal with them specially.
808 	 */
809 	if (!handle)
810 		return acpi_root;
811 
812 	do {
813 		status = acpi_get_parent(handle, &handle);
814 		if (ACPI_FAILURE(status))
815 			return status == AE_NULL_ENTRY ? NULL : acpi_root;
816 	} while (acpi_bus_get_device(handle, &device));
817 	return device;
818 }
819 
820 acpi_status
821 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
822 {
823 	acpi_status status;
824 	acpi_handle tmp;
825 	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
826 	union acpi_object *obj;
827 
828 	status = acpi_get_handle(handle, "_EJD", &tmp);
829 	if (ACPI_FAILURE(status))
830 		return status;
831 
832 	status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
833 	if (ACPI_SUCCESS(status)) {
834 		obj = buffer.pointer;
835 		status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
836 					 ejd);
837 		kfree(buffer.pointer);
838 	}
839 	return status;
840 }
841 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
842 
843 static int acpi_bus_extract_wakeup_device_power_package(struct acpi_device *dev)
844 {
845 	acpi_handle handle = dev->handle;
846 	struct acpi_device_wakeup *wakeup = &dev->wakeup;
847 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
848 	union acpi_object *package = NULL;
849 	union acpi_object *element = NULL;
850 	acpi_status status;
851 	int err = -ENODATA;
852 
853 	INIT_LIST_HEAD(&wakeup->resources);
854 
855 	/* _PRW */
856 	status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
857 	if (ACPI_FAILURE(status)) {
858 		acpi_handle_info(handle, "_PRW evaluation failed: %s\n",
859 				 acpi_format_exception(status));
860 		return err;
861 	}
862 
863 	package = (union acpi_object *)buffer.pointer;
864 
865 	if (!package || package->package.count < 2)
866 		goto out;
867 
868 	element = &(package->package.elements[0]);
869 	if (!element)
870 		goto out;
871 
872 	if (element->type == ACPI_TYPE_PACKAGE) {
873 		if ((element->package.count < 2) ||
874 		    (element->package.elements[0].type !=
875 		     ACPI_TYPE_LOCAL_REFERENCE)
876 		    || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
877 			goto out;
878 
879 		wakeup->gpe_device =
880 		    element->package.elements[0].reference.handle;
881 		wakeup->gpe_number =
882 		    (u32) element->package.elements[1].integer.value;
883 	} else if (element->type == ACPI_TYPE_INTEGER) {
884 		wakeup->gpe_device = NULL;
885 		wakeup->gpe_number = element->integer.value;
886 	} else {
887 		goto out;
888 	}
889 
890 	element = &(package->package.elements[1]);
891 	if (element->type != ACPI_TYPE_INTEGER)
892 		goto out;
893 
894 	wakeup->sleep_state = element->integer.value;
895 
896 	err = acpi_extract_power_resources(package, 2, &wakeup->resources);
897 	if (err)
898 		goto out;
899 
900 	if (!list_empty(&wakeup->resources)) {
901 		int sleep_state;
902 
903 		err = acpi_power_wakeup_list_init(&wakeup->resources,
904 						  &sleep_state);
905 		if (err) {
906 			acpi_handle_warn(handle, "Retrieving current states "
907 					 "of wakeup power resources failed\n");
908 			acpi_power_resources_list_free(&wakeup->resources);
909 			goto out;
910 		}
911 		if (sleep_state < wakeup->sleep_state) {
912 			acpi_handle_warn(handle, "Overriding _PRW sleep state "
913 					 "(S%d) by S%d from power resources\n",
914 					 (int)wakeup->sleep_state, sleep_state);
915 			wakeup->sleep_state = sleep_state;
916 		}
917 	}
918 
919  out:
920 	kfree(buffer.pointer);
921 	return err;
922 }
923 
924 static bool acpi_wakeup_gpe_init(struct acpi_device *device)
925 {
926 	static const struct acpi_device_id button_device_ids[] = {
927 		{"PNP0C0C", 0},		/* Power button */
928 		{"PNP0C0D", 0},		/* Lid */
929 		{"PNP0C0E", 0},		/* Sleep button */
930 		{"", 0},
931 	};
932 	struct acpi_device_wakeup *wakeup = &device->wakeup;
933 	acpi_status status;
934 
935 	wakeup->flags.notifier_present = 0;
936 
937 	/* Power button, Lid switch always enable wakeup */
938 	if (!acpi_match_device_ids(device, button_device_ids)) {
939 		if (!acpi_match_device_ids(device, &button_device_ids[1])) {
940 			/* Do not use Lid/sleep button for S5 wakeup */
941 			if (wakeup->sleep_state == ACPI_STATE_S5)
942 				wakeup->sleep_state = ACPI_STATE_S4;
943 		}
944 		acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
945 		device_set_wakeup_capable(&device->dev, true);
946 		return true;
947 	}
948 
949 	status = acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
950 					 wakeup->gpe_number);
951 	return ACPI_SUCCESS(status);
952 }
953 
954 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
955 {
956 	int err;
957 
958 	/* Presence of _PRW indicates wake capable */
959 	if (!acpi_has_method(device->handle, "_PRW"))
960 		return;
961 
962 	err = acpi_bus_extract_wakeup_device_power_package(device);
963 	if (err) {
964 		dev_err(&device->dev, "Unable to extract wakeup power resources");
965 		return;
966 	}
967 
968 	device->wakeup.flags.valid = acpi_wakeup_gpe_init(device);
969 	device->wakeup.prepare_count = 0;
970 	/*
971 	 * Call _PSW/_DSW object to disable its ability to wake the sleeping
972 	 * system for the ACPI device with the _PRW object.
973 	 * The _PSW object is deprecated in ACPI 3.0 and is replaced by _DSW.
974 	 * So it is necessary to call _DSW object first. Only when it is not
975 	 * present will the _PSW object used.
976 	 */
977 	err = acpi_device_sleep_wake(device, 0, 0, 0);
978 	if (err)
979 		pr_debug("error in _DSW or _PSW evaluation\n");
980 }
981 
982 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
983 {
984 	struct acpi_device_power_state *ps = &device->power.states[state];
985 	char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
986 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
987 	acpi_status status;
988 
989 	INIT_LIST_HEAD(&ps->resources);
990 
991 	/* Evaluate "_PRx" to get referenced power resources */
992 	status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
993 	if (ACPI_SUCCESS(status)) {
994 		union acpi_object *package = buffer.pointer;
995 
996 		if (buffer.length && package
997 		    && package->type == ACPI_TYPE_PACKAGE
998 		    && package->package.count)
999 			acpi_extract_power_resources(package, 0, &ps->resources);
1000 
1001 		ACPI_FREE(buffer.pointer);
1002 	}
1003 
1004 	/* Evaluate "_PSx" to see if we can do explicit sets */
1005 	pathname[2] = 'S';
1006 	if (acpi_has_method(device->handle, pathname))
1007 		ps->flags.explicit_set = 1;
1008 
1009 	/* State is valid if there are means to put the device into it. */
1010 	if (!list_empty(&ps->resources) || ps->flags.explicit_set)
1011 		ps->flags.valid = 1;
1012 
1013 	ps->power = -1;		/* Unknown - driver assigned */
1014 	ps->latency = -1;	/* Unknown - driver assigned */
1015 }
1016 
1017 static void acpi_bus_get_power_flags(struct acpi_device *device)
1018 {
1019 	u32 i;
1020 
1021 	/* Presence of _PS0|_PR0 indicates 'power manageable' */
1022 	if (!acpi_has_method(device->handle, "_PS0") &&
1023 	    !acpi_has_method(device->handle, "_PR0"))
1024 		return;
1025 
1026 	device->flags.power_manageable = 1;
1027 
1028 	/*
1029 	 * Power Management Flags
1030 	 */
1031 	if (acpi_has_method(device->handle, "_PSC"))
1032 		device->power.flags.explicit_get = 1;
1033 
1034 	if (acpi_has_method(device->handle, "_IRC"))
1035 		device->power.flags.inrush_current = 1;
1036 
1037 	if (acpi_has_method(device->handle, "_DSW"))
1038 		device->power.flags.dsw_present = 1;
1039 
1040 	/*
1041 	 * Enumerate supported power management states
1042 	 */
1043 	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
1044 		acpi_bus_init_power_state(device, i);
1045 
1046 	INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
1047 
1048 	/* Set the defaults for D0 and D3hot (always supported). */
1049 	device->power.states[ACPI_STATE_D0].flags.valid = 1;
1050 	device->power.states[ACPI_STATE_D0].power = 100;
1051 	device->power.states[ACPI_STATE_D3_HOT].flags.valid = 1;
1052 
1053 	/*
1054 	 * Use power resources only if the D0 list of them is populated, because
1055 	 * some platforms may provide _PR3 only to indicate D3cold support and
1056 	 * in those cases the power resources list returned by it may be bogus.
1057 	 */
1058 	if (!list_empty(&device->power.states[ACPI_STATE_D0].resources)) {
1059 		device->power.flags.power_resources = 1;
1060 		/*
1061 		 * D3cold is supported if the D3hot list of power resources is
1062 		 * not empty.
1063 		 */
1064 		if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources))
1065 			device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
1066 	}
1067 
1068 	if (acpi_bus_init_power(device))
1069 		device->flags.power_manageable = 0;
1070 }
1071 
1072 static void acpi_bus_get_flags(struct acpi_device *device)
1073 {
1074 	/* Presence of _STA indicates 'dynamic_status' */
1075 	if (acpi_has_method(device->handle, "_STA"))
1076 		device->flags.dynamic_status = 1;
1077 
1078 	/* Presence of _RMV indicates 'removable' */
1079 	if (acpi_has_method(device->handle, "_RMV"))
1080 		device->flags.removable = 1;
1081 
1082 	/* Presence of _EJD|_EJ0 indicates 'ejectable' */
1083 	if (acpi_has_method(device->handle, "_EJD") ||
1084 	    acpi_has_method(device->handle, "_EJ0"))
1085 		device->flags.ejectable = 1;
1086 }
1087 
1088 static void acpi_device_get_busid(struct acpi_device *device)
1089 {
1090 	char bus_id[5] = { '?', 0 };
1091 	struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1092 	int i = 0;
1093 
1094 	/*
1095 	 * Bus ID
1096 	 * ------
1097 	 * The device's Bus ID is simply the object name.
1098 	 * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1099 	 */
1100 	if (ACPI_IS_ROOT_DEVICE(device)) {
1101 		strcpy(device->pnp.bus_id, "ACPI");
1102 		return;
1103 	}
1104 
1105 	switch (device->device_type) {
1106 	case ACPI_BUS_TYPE_POWER_BUTTON:
1107 		strcpy(device->pnp.bus_id, "PWRF");
1108 		break;
1109 	case ACPI_BUS_TYPE_SLEEP_BUTTON:
1110 		strcpy(device->pnp.bus_id, "SLPF");
1111 		break;
1112 	case ACPI_BUS_TYPE_ECDT_EC:
1113 		strcpy(device->pnp.bus_id, "ECDT");
1114 		break;
1115 	default:
1116 		acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1117 		/* Clean up trailing underscores (if any) */
1118 		for (i = 3; i > 1; i--) {
1119 			if (bus_id[i] == '_')
1120 				bus_id[i] = '\0';
1121 			else
1122 				break;
1123 		}
1124 		strcpy(device->pnp.bus_id, bus_id);
1125 		break;
1126 	}
1127 }
1128 
1129 /*
1130  * acpi_ata_match - see if an acpi object is an ATA device
1131  *
1132  * If an acpi object has one of the ACPI ATA methods defined,
1133  * then we can safely call it an ATA device.
1134  */
1135 bool acpi_ata_match(acpi_handle handle)
1136 {
1137 	return acpi_has_method(handle, "_GTF") ||
1138 	       acpi_has_method(handle, "_GTM") ||
1139 	       acpi_has_method(handle, "_STM") ||
1140 	       acpi_has_method(handle, "_SDD");
1141 }
1142 
1143 /*
1144  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1145  *
1146  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1147  * then we can safely call it an ejectable drive bay
1148  */
1149 bool acpi_bay_match(acpi_handle handle)
1150 {
1151 	acpi_handle phandle;
1152 
1153 	if (!acpi_has_method(handle, "_EJ0"))
1154 		return false;
1155 	if (acpi_ata_match(handle))
1156 		return true;
1157 	if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1158 		return false;
1159 
1160 	return acpi_ata_match(phandle);
1161 }
1162 
1163 bool acpi_device_is_battery(struct acpi_device *adev)
1164 {
1165 	struct acpi_hardware_id *hwid;
1166 
1167 	list_for_each_entry(hwid, &adev->pnp.ids, list)
1168 		if (!strcmp("PNP0C0A", hwid->id))
1169 			return true;
1170 
1171 	return false;
1172 }
1173 
1174 static bool is_ejectable_bay(struct acpi_device *adev)
1175 {
1176 	acpi_handle handle = adev->handle;
1177 
1178 	if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
1179 		return true;
1180 
1181 	return acpi_bay_match(handle);
1182 }
1183 
1184 /*
1185  * acpi_dock_match - see if an acpi object has a _DCK method
1186  */
1187 bool acpi_dock_match(acpi_handle handle)
1188 {
1189 	return acpi_has_method(handle, "_DCK");
1190 }
1191 
1192 static acpi_status
1193 acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
1194 			  void **return_value)
1195 {
1196 	long *cap = context;
1197 
1198 	if (acpi_has_method(handle, "_BCM") &&
1199 	    acpi_has_method(handle, "_BCL")) {
1200 		acpi_handle_debug(handle, "Found generic backlight support\n");
1201 		*cap |= ACPI_VIDEO_BACKLIGHT;
1202 		/* We have backlight support, no need to scan further */
1203 		return AE_CTRL_TERMINATE;
1204 	}
1205 	return 0;
1206 }
1207 
1208 /* Returns true if the ACPI object is a video device which can be
1209  * handled by video.ko.
1210  * The device will get a Linux specific CID added in scan.c to
1211  * identify the device as an ACPI graphics device
1212  * Be aware that the graphics device may not be physically present
1213  * Use acpi_video_get_capabilities() to detect general ACPI video
1214  * capabilities of present cards
1215  */
1216 long acpi_is_video_device(acpi_handle handle)
1217 {
1218 	long video_caps = 0;
1219 
1220 	/* Is this device able to support video switching ? */
1221 	if (acpi_has_method(handle, "_DOD") || acpi_has_method(handle, "_DOS"))
1222 		video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
1223 
1224 	/* Is this device able to retrieve a video ROM ? */
1225 	if (acpi_has_method(handle, "_ROM"))
1226 		video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
1227 
1228 	/* Is this device able to configure which video head to be POSTed ? */
1229 	if (acpi_has_method(handle, "_VPO") &&
1230 	    acpi_has_method(handle, "_GPD") &&
1231 	    acpi_has_method(handle, "_SPD"))
1232 		video_caps |= ACPI_VIDEO_DEVICE_POSTING;
1233 
1234 	/* Only check for backlight functionality if one of the above hit. */
1235 	if (video_caps)
1236 		acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
1237 				    ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
1238 				    &video_caps, NULL);
1239 
1240 	return video_caps;
1241 }
1242 EXPORT_SYMBOL(acpi_is_video_device);
1243 
1244 const char *acpi_device_hid(struct acpi_device *device)
1245 {
1246 	struct acpi_hardware_id *hid;
1247 
1248 	if (list_empty(&device->pnp.ids))
1249 		return dummy_hid;
1250 
1251 	hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1252 	return hid->id;
1253 }
1254 EXPORT_SYMBOL(acpi_device_hid);
1255 
1256 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1257 {
1258 	struct acpi_hardware_id *id;
1259 
1260 	id = kmalloc(sizeof(*id), GFP_KERNEL);
1261 	if (!id)
1262 		return;
1263 
1264 	id->id = kstrdup_const(dev_id, GFP_KERNEL);
1265 	if (!id->id) {
1266 		kfree(id);
1267 		return;
1268 	}
1269 
1270 	list_add_tail(&id->list, &pnp->ids);
1271 	pnp->type.hardware_id = 1;
1272 }
1273 
1274 /*
1275  * Old IBM workstations have a DSDT bug wherein the SMBus object
1276  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1277  * prefix.  Work around this.
1278  */
1279 static bool acpi_ibm_smbus_match(acpi_handle handle)
1280 {
1281 	char node_name[ACPI_PATH_SEGMENT_LENGTH];
1282 	struct acpi_buffer path = { sizeof(node_name), node_name };
1283 
1284 	if (!dmi_name_in_vendors("IBM"))
1285 		return false;
1286 
1287 	/* Look for SMBS object */
1288 	if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1289 	    strcmp("SMBS", path.pointer))
1290 		return false;
1291 
1292 	/* Does it have the necessary (but misnamed) methods? */
1293 	if (acpi_has_method(handle, "SBI") &&
1294 	    acpi_has_method(handle, "SBR") &&
1295 	    acpi_has_method(handle, "SBW"))
1296 		return true;
1297 
1298 	return false;
1299 }
1300 
1301 static bool acpi_object_is_system_bus(acpi_handle handle)
1302 {
1303 	acpi_handle tmp;
1304 
1305 	if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
1306 	    tmp == handle)
1307 		return true;
1308 	if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
1309 	    tmp == handle)
1310 		return true;
1311 
1312 	return false;
1313 }
1314 
1315 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1316 			     int device_type)
1317 {
1318 	struct acpi_device_info *info = NULL;
1319 	struct acpi_pnp_device_id_list *cid_list;
1320 	int i;
1321 
1322 	switch (device_type) {
1323 	case ACPI_BUS_TYPE_DEVICE:
1324 		if (handle == ACPI_ROOT_OBJECT) {
1325 			acpi_add_id(pnp, ACPI_SYSTEM_HID);
1326 			break;
1327 		}
1328 
1329 		acpi_get_object_info(handle, &info);
1330 		if (!info) {
1331 			pr_err("%s: Error reading device info\n", __func__);
1332 			return;
1333 		}
1334 
1335 		if (info->valid & ACPI_VALID_HID) {
1336 			acpi_add_id(pnp, info->hardware_id.string);
1337 			pnp->type.platform_id = 1;
1338 		}
1339 		if (info->valid & ACPI_VALID_CID) {
1340 			cid_list = &info->compatible_id_list;
1341 			for (i = 0; i < cid_list->count; i++)
1342 				acpi_add_id(pnp, cid_list->ids[i].string);
1343 		}
1344 		if (info->valid & ACPI_VALID_ADR) {
1345 			pnp->bus_address = info->address;
1346 			pnp->type.bus_address = 1;
1347 		}
1348 		if (info->valid & ACPI_VALID_UID)
1349 			pnp->unique_id = kstrdup(info->unique_id.string,
1350 							GFP_KERNEL);
1351 		if (info->valid & ACPI_VALID_CLS)
1352 			acpi_add_id(pnp, info->class_code.string);
1353 
1354 		kfree(info);
1355 
1356 		/*
1357 		 * Some devices don't reliably have _HIDs & _CIDs, so add
1358 		 * synthetic HIDs to make sure drivers can find them.
1359 		 */
1360 		if (acpi_is_video_device(handle))
1361 			acpi_add_id(pnp, ACPI_VIDEO_HID);
1362 		else if (acpi_bay_match(handle))
1363 			acpi_add_id(pnp, ACPI_BAY_HID);
1364 		else if (acpi_dock_match(handle))
1365 			acpi_add_id(pnp, ACPI_DOCK_HID);
1366 		else if (acpi_ibm_smbus_match(handle))
1367 			acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1368 		else if (list_empty(&pnp->ids) &&
1369 			 acpi_object_is_system_bus(handle)) {
1370 			/* \_SB, \_TZ, LNXSYBUS */
1371 			acpi_add_id(pnp, ACPI_BUS_HID);
1372 			strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1373 			strcpy(pnp->device_class, ACPI_BUS_CLASS);
1374 		}
1375 
1376 		break;
1377 	case ACPI_BUS_TYPE_POWER:
1378 		acpi_add_id(pnp, ACPI_POWER_HID);
1379 		break;
1380 	case ACPI_BUS_TYPE_PROCESSOR:
1381 		acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1382 		break;
1383 	case ACPI_BUS_TYPE_THERMAL:
1384 		acpi_add_id(pnp, ACPI_THERMAL_HID);
1385 		break;
1386 	case ACPI_BUS_TYPE_POWER_BUTTON:
1387 		acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1388 		break;
1389 	case ACPI_BUS_TYPE_SLEEP_BUTTON:
1390 		acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1391 		break;
1392 	case ACPI_BUS_TYPE_ECDT_EC:
1393 		acpi_add_id(pnp, ACPI_ECDT_HID);
1394 		break;
1395 	}
1396 }
1397 
1398 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1399 {
1400 	struct acpi_hardware_id *id, *tmp;
1401 
1402 	list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1403 		kfree_const(id->id);
1404 		kfree(id);
1405 	}
1406 	kfree(pnp->unique_id);
1407 }
1408 
1409 /**
1410  * acpi_dma_supported - Check DMA support for the specified device.
1411  * @adev: The pointer to acpi device
1412  *
1413  * Return false if DMA is not supported. Otherwise, return true
1414  */
1415 bool acpi_dma_supported(const struct acpi_device *adev)
1416 {
1417 	if (!adev)
1418 		return false;
1419 
1420 	if (adev->flags.cca_seen)
1421 		return true;
1422 
1423 	/*
1424 	* Per ACPI 6.0 sec 6.2.17, assume devices can do cache-coherent
1425 	* DMA on "Intel platforms".  Presumably that includes all x86 and
1426 	* ia64, and other arches will set CONFIG_ACPI_CCA_REQUIRED=y.
1427 	*/
1428 	if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1429 		return true;
1430 
1431 	return false;
1432 }
1433 
1434 /**
1435  * acpi_get_dma_attr - Check the supported DMA attr for the specified device.
1436  * @adev: The pointer to acpi device
1437  *
1438  * Return enum dev_dma_attr.
1439  */
1440 enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
1441 {
1442 	if (!acpi_dma_supported(adev))
1443 		return DEV_DMA_NOT_SUPPORTED;
1444 
1445 	if (adev->flags.coherent_dma)
1446 		return DEV_DMA_COHERENT;
1447 	else
1448 		return DEV_DMA_NON_COHERENT;
1449 }
1450 
1451 /**
1452  * acpi_dma_get_range() - Get device DMA parameters.
1453  *
1454  * @dev: device to configure
1455  * @dma_addr: pointer device DMA address result
1456  * @offset: pointer to the DMA offset result
1457  * @size: pointer to DMA range size result
1458  *
1459  * Evaluate DMA regions and return respectively DMA region start, offset
1460  * and size in dma_addr, offset and size on parsing success; it does not
1461  * update the passed in values on failure.
1462  *
1463  * Return 0 on success, < 0 on failure.
1464  */
1465 int acpi_dma_get_range(struct device *dev, u64 *dma_addr, u64 *offset,
1466 		       u64 *size)
1467 {
1468 	struct acpi_device *adev;
1469 	LIST_HEAD(list);
1470 	struct resource_entry *rentry;
1471 	int ret;
1472 	struct device *dma_dev = dev;
1473 	u64 len, dma_start = U64_MAX, dma_end = 0, dma_offset = 0;
1474 
1475 	/*
1476 	 * Walk the device tree chasing an ACPI companion with a _DMA
1477 	 * object while we go. Stop if we find a device with an ACPI
1478 	 * companion containing a _DMA method.
1479 	 */
1480 	do {
1481 		adev = ACPI_COMPANION(dma_dev);
1482 		if (adev && acpi_has_method(adev->handle, METHOD_NAME__DMA))
1483 			break;
1484 
1485 		dma_dev = dma_dev->parent;
1486 	} while (dma_dev);
1487 
1488 	if (!dma_dev)
1489 		return -ENODEV;
1490 
1491 	if (!acpi_has_method(adev->handle, METHOD_NAME__CRS)) {
1492 		acpi_handle_warn(adev->handle, "_DMA is valid only if _CRS is present\n");
1493 		return -EINVAL;
1494 	}
1495 
1496 	ret = acpi_dev_get_dma_resources(adev, &list);
1497 	if (ret > 0) {
1498 		list_for_each_entry(rentry, &list, node) {
1499 			if (dma_offset && rentry->offset != dma_offset) {
1500 				ret = -EINVAL;
1501 				dev_warn(dma_dev, "Can't handle multiple windows with different offsets\n");
1502 				goto out;
1503 			}
1504 			dma_offset = rentry->offset;
1505 
1506 			/* Take lower and upper limits */
1507 			if (rentry->res->start < dma_start)
1508 				dma_start = rentry->res->start;
1509 			if (rentry->res->end > dma_end)
1510 				dma_end = rentry->res->end;
1511 		}
1512 
1513 		if (dma_start >= dma_end) {
1514 			ret = -EINVAL;
1515 			dev_dbg(dma_dev, "Invalid DMA regions configuration\n");
1516 			goto out;
1517 		}
1518 
1519 		*dma_addr = dma_start - dma_offset;
1520 		len = dma_end - dma_start;
1521 		*size = max(len, len + 1);
1522 		*offset = dma_offset;
1523 	}
1524  out:
1525 	acpi_dev_free_resource_list(&list);
1526 
1527 	return ret >= 0 ? 0 : ret;
1528 }
1529 
1530 #ifdef CONFIG_IOMMU_API
1531 int acpi_iommu_fwspec_init(struct device *dev, u32 id,
1532 			   struct fwnode_handle *fwnode,
1533 			   const struct iommu_ops *ops)
1534 {
1535 	int ret = iommu_fwspec_init(dev, fwnode, ops);
1536 
1537 	if (!ret)
1538 		ret = iommu_fwspec_add_ids(dev, &id, 1);
1539 
1540 	return ret;
1541 }
1542 
1543 static inline const struct iommu_ops *acpi_iommu_fwspec_ops(struct device *dev)
1544 {
1545 	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
1546 
1547 	return fwspec ? fwspec->ops : NULL;
1548 }
1549 
1550 static const struct iommu_ops *acpi_iommu_configure_id(struct device *dev,
1551 						       const u32 *id_in)
1552 {
1553 	int err;
1554 	const struct iommu_ops *ops;
1555 
1556 	/*
1557 	 * If we already translated the fwspec there is nothing left to do,
1558 	 * return the iommu_ops.
1559 	 */
1560 	ops = acpi_iommu_fwspec_ops(dev);
1561 	if (ops)
1562 		return ops;
1563 
1564 	err = iort_iommu_configure_id(dev, id_in);
1565 	if (err && err != -EPROBE_DEFER)
1566 		err = viot_iommu_configure(dev);
1567 
1568 	/*
1569 	 * If we have reason to believe the IOMMU driver missed the initial
1570 	 * iommu_probe_device() call for dev, replay it to get things in order.
1571 	 */
1572 	if (!err && dev->bus && !device_iommu_mapped(dev))
1573 		err = iommu_probe_device(dev);
1574 
1575 	/* Ignore all other errors apart from EPROBE_DEFER */
1576 	if (err == -EPROBE_DEFER) {
1577 		return ERR_PTR(err);
1578 	} else if (err) {
1579 		dev_dbg(dev, "Adding to IOMMU failed: %d\n", err);
1580 		return NULL;
1581 	}
1582 	return acpi_iommu_fwspec_ops(dev);
1583 }
1584 
1585 #else /* !CONFIG_IOMMU_API */
1586 
1587 int acpi_iommu_fwspec_init(struct device *dev, u32 id,
1588 			   struct fwnode_handle *fwnode,
1589 			   const struct iommu_ops *ops)
1590 {
1591 	return -ENODEV;
1592 }
1593 
1594 static const struct iommu_ops *acpi_iommu_configure_id(struct device *dev,
1595 						       const u32 *id_in)
1596 {
1597 	return NULL;
1598 }
1599 
1600 #endif /* !CONFIG_IOMMU_API */
1601 
1602 /**
1603  * acpi_dma_configure_id - Set-up DMA configuration for the device.
1604  * @dev: The pointer to the device
1605  * @attr: device dma attributes
1606  * @input_id: input device id const value pointer
1607  */
1608 int acpi_dma_configure_id(struct device *dev, enum dev_dma_attr attr,
1609 			  const u32 *input_id)
1610 {
1611 	const struct iommu_ops *iommu;
1612 	u64 dma_addr = 0, size = 0;
1613 
1614 	if (attr == DEV_DMA_NOT_SUPPORTED) {
1615 		set_dma_ops(dev, &dma_dummy_ops);
1616 		return 0;
1617 	}
1618 
1619 	acpi_arch_dma_setup(dev, &dma_addr, &size);
1620 
1621 	iommu = acpi_iommu_configure_id(dev, input_id);
1622 	if (PTR_ERR(iommu) == -EPROBE_DEFER)
1623 		return -EPROBE_DEFER;
1624 
1625 	arch_setup_dma_ops(dev, dma_addr, size,
1626 				iommu, attr == DEV_DMA_COHERENT);
1627 
1628 	return 0;
1629 }
1630 EXPORT_SYMBOL_GPL(acpi_dma_configure_id);
1631 
1632 static void acpi_init_coherency(struct acpi_device *adev)
1633 {
1634 	unsigned long long cca = 0;
1635 	acpi_status status;
1636 	struct acpi_device *parent = adev->parent;
1637 
1638 	if (parent && parent->flags.cca_seen) {
1639 		/*
1640 		 * From ACPI spec, OSPM will ignore _CCA if an ancestor
1641 		 * already saw one.
1642 		 */
1643 		adev->flags.cca_seen = 1;
1644 		cca = parent->flags.coherent_dma;
1645 	} else {
1646 		status = acpi_evaluate_integer(adev->handle, "_CCA",
1647 					       NULL, &cca);
1648 		if (ACPI_SUCCESS(status))
1649 			adev->flags.cca_seen = 1;
1650 		else if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1651 			/*
1652 			 * If architecture does not specify that _CCA is
1653 			 * required for DMA-able devices (e.g. x86),
1654 			 * we default to _CCA=1.
1655 			 */
1656 			cca = 1;
1657 		else
1658 			acpi_handle_debug(adev->handle,
1659 					  "ACPI device is missing _CCA.\n");
1660 	}
1661 
1662 	adev->flags.coherent_dma = cca;
1663 }
1664 
1665 static int acpi_check_serial_bus_slave(struct acpi_resource *ares, void *data)
1666 {
1667 	bool *is_serial_bus_slave_p = data;
1668 
1669 	if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
1670 		return 1;
1671 
1672 	*is_serial_bus_slave_p = true;
1673 
1674 	 /* no need to do more checking */
1675 	return -1;
1676 }
1677 
1678 static bool acpi_is_indirect_io_slave(struct acpi_device *device)
1679 {
1680 	struct acpi_device *parent = device->parent;
1681 	static const struct acpi_device_id indirect_io_hosts[] = {
1682 		{"HISI0191", 0},
1683 		{}
1684 	};
1685 
1686 	return parent && !acpi_match_device_ids(parent, indirect_io_hosts);
1687 }
1688 
1689 static bool acpi_device_enumeration_by_parent(struct acpi_device *device)
1690 {
1691 	struct list_head resource_list;
1692 	bool is_serial_bus_slave = false;
1693 	/*
1694 	 * These devices have multiple I2cSerialBus resources and an i2c-client
1695 	 * must be instantiated for each, each with its own i2c_device_id.
1696 	 * Normally we only instantiate an i2c-client for the first resource,
1697 	 * using the ACPI HID as id. These special cases are handled by the
1698 	 * drivers/platform/x86/i2c-multi-instantiate.c driver, which knows
1699 	 * which i2c_device_id to use for each resource.
1700 	 */
1701 	static const struct acpi_device_id i2c_multi_instantiate_ids[] = {
1702 		{"BSG1160", },
1703 		{"BSG2150", },
1704 		{"INT33FE", },
1705 		{"INT3515", },
1706 		{}
1707 	};
1708 
1709 	if (acpi_is_indirect_io_slave(device))
1710 		return true;
1711 
1712 	/* Macs use device properties in lieu of _CRS resources */
1713 	if (x86_apple_machine &&
1714 	    (fwnode_property_present(&device->fwnode, "spiSclkPeriod") ||
1715 	     fwnode_property_present(&device->fwnode, "i2cAddress") ||
1716 	     fwnode_property_present(&device->fwnode, "baud")))
1717 		return true;
1718 
1719 	/* Instantiate a pdev for the i2c-multi-instantiate drv to bind to */
1720 	if (!acpi_match_device_ids(device, i2c_multi_instantiate_ids))
1721 		return false;
1722 
1723 	INIT_LIST_HEAD(&resource_list);
1724 	acpi_dev_get_resources(device, &resource_list,
1725 			       acpi_check_serial_bus_slave,
1726 			       &is_serial_bus_slave);
1727 	acpi_dev_free_resource_list(&resource_list);
1728 
1729 	return is_serial_bus_slave;
1730 }
1731 
1732 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1733 			     int type)
1734 {
1735 	INIT_LIST_HEAD(&device->pnp.ids);
1736 	device->device_type = type;
1737 	device->handle = handle;
1738 	device->parent = acpi_bus_get_parent(handle);
1739 	fwnode_init(&device->fwnode, &acpi_device_fwnode_ops);
1740 	acpi_set_device_status(device, ACPI_STA_DEFAULT);
1741 	acpi_device_get_busid(device);
1742 	acpi_set_pnp_ids(handle, &device->pnp, type);
1743 	acpi_init_properties(device);
1744 	acpi_bus_get_flags(device);
1745 	device->flags.match_driver = false;
1746 	device->flags.initialized = true;
1747 	device->flags.enumeration_by_parent =
1748 		acpi_device_enumeration_by_parent(device);
1749 	acpi_device_clear_enumerated(device);
1750 	device_initialize(&device->dev);
1751 	dev_set_uevent_suppress(&device->dev, true);
1752 	acpi_init_coherency(device);
1753 }
1754 
1755 static void acpi_scan_dep_init(struct acpi_device *adev)
1756 {
1757 	struct acpi_dep_data *dep;
1758 
1759 	list_for_each_entry(dep, &acpi_dep_list, node) {
1760 		if (dep->consumer == adev->handle)
1761 			adev->dep_unmet++;
1762 	}
1763 }
1764 
1765 void acpi_device_add_finalize(struct acpi_device *device)
1766 {
1767 	dev_set_uevent_suppress(&device->dev, false);
1768 	kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1769 }
1770 
1771 static void acpi_scan_init_status(struct acpi_device *adev)
1772 {
1773 	if (acpi_bus_get_status(adev))
1774 		acpi_set_device_status(adev, 0);
1775 }
1776 
1777 static int acpi_add_single_object(struct acpi_device **child,
1778 				  acpi_handle handle, int type, bool dep_init)
1779 {
1780 	struct acpi_device *device;
1781 	bool release_dep_lock = false;
1782 	int result;
1783 
1784 	device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1785 	if (!device)
1786 		return -ENOMEM;
1787 
1788 	acpi_init_device_object(device, handle, type);
1789 	/*
1790 	 * Getting the status is delayed till here so that we can call
1791 	 * acpi_bus_get_status() and use its quirk handling.  Note that
1792 	 * this must be done before the get power-/wakeup_dev-flags calls.
1793 	 */
1794 	if (type == ACPI_BUS_TYPE_DEVICE || type == ACPI_BUS_TYPE_PROCESSOR) {
1795 		if (dep_init) {
1796 			mutex_lock(&acpi_dep_list_lock);
1797 			/*
1798 			 * Hold the lock until the acpi_tie_acpi_dev() call
1799 			 * below to prevent concurrent acpi_scan_clear_dep()
1800 			 * from deleting a dependency list entry without
1801 			 * updating dep_unmet for the device.
1802 			 */
1803 			release_dep_lock = true;
1804 			acpi_scan_dep_init(device);
1805 		}
1806 		acpi_scan_init_status(device);
1807 	}
1808 
1809 	acpi_bus_get_power_flags(device);
1810 	acpi_bus_get_wakeup_device_flags(device);
1811 
1812 	result = acpi_tie_acpi_dev(device);
1813 
1814 	if (release_dep_lock)
1815 		mutex_unlock(&acpi_dep_list_lock);
1816 
1817 	if (!result)
1818 		result = __acpi_device_add(device, acpi_device_release);
1819 
1820 	if (result) {
1821 		acpi_device_release(&device->dev);
1822 		return result;
1823 	}
1824 
1825 	acpi_power_add_remove_device(device, true);
1826 	acpi_device_add_finalize(device);
1827 
1828 	acpi_handle_debug(handle, "Added as %s, parent %s\n",
1829 			  dev_name(&device->dev), device->parent ?
1830 				dev_name(&device->parent->dev) : "(null)");
1831 
1832 	*child = device;
1833 	return 0;
1834 }
1835 
1836 static acpi_status acpi_get_resource_memory(struct acpi_resource *ares,
1837 					    void *context)
1838 {
1839 	struct resource *res = context;
1840 
1841 	if (acpi_dev_resource_memory(ares, res))
1842 		return AE_CTRL_TERMINATE;
1843 
1844 	return AE_OK;
1845 }
1846 
1847 static bool acpi_device_should_be_hidden(acpi_handle handle)
1848 {
1849 	acpi_status status;
1850 	struct resource res;
1851 
1852 	/* Check if it should ignore the UART device */
1853 	if (!(spcr_uart_addr && acpi_has_method(handle, METHOD_NAME__CRS)))
1854 		return false;
1855 
1856 	/*
1857 	 * The UART device described in SPCR table is assumed to have only one
1858 	 * memory resource present. So we only look for the first one here.
1859 	 */
1860 	status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1861 				     acpi_get_resource_memory, &res);
1862 	if (ACPI_FAILURE(status) || res.start != spcr_uart_addr)
1863 		return false;
1864 
1865 	acpi_handle_info(handle, "The UART device @%pa in SPCR table will be hidden\n",
1866 			 &res.start);
1867 
1868 	return true;
1869 }
1870 
1871 bool acpi_device_is_present(const struct acpi_device *adev)
1872 {
1873 	return adev->status.present || adev->status.functional;
1874 }
1875 
1876 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1877 				       const char *idstr,
1878 				       const struct acpi_device_id **matchid)
1879 {
1880 	const struct acpi_device_id *devid;
1881 
1882 	if (handler->match)
1883 		return handler->match(idstr, matchid);
1884 
1885 	for (devid = handler->ids; devid->id[0]; devid++)
1886 		if (!strcmp((char *)devid->id, idstr)) {
1887 			if (matchid)
1888 				*matchid = devid;
1889 
1890 			return true;
1891 		}
1892 
1893 	return false;
1894 }
1895 
1896 static struct acpi_scan_handler *acpi_scan_match_handler(const char *idstr,
1897 					const struct acpi_device_id **matchid)
1898 {
1899 	struct acpi_scan_handler *handler;
1900 
1901 	list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1902 		if (acpi_scan_handler_matching(handler, idstr, matchid))
1903 			return handler;
1904 
1905 	return NULL;
1906 }
1907 
1908 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1909 {
1910 	if (!!hotplug->enabled == !!val)
1911 		return;
1912 
1913 	mutex_lock(&acpi_scan_lock);
1914 
1915 	hotplug->enabled = val;
1916 
1917 	mutex_unlock(&acpi_scan_lock);
1918 }
1919 
1920 static void acpi_scan_init_hotplug(struct acpi_device *adev)
1921 {
1922 	struct acpi_hardware_id *hwid;
1923 
1924 	if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
1925 		acpi_dock_add(adev);
1926 		return;
1927 	}
1928 	list_for_each_entry(hwid, &adev->pnp.ids, list) {
1929 		struct acpi_scan_handler *handler;
1930 
1931 		handler = acpi_scan_match_handler(hwid->id, NULL);
1932 		if (handler) {
1933 			adev->flags.hotplug_notify = true;
1934 			break;
1935 		}
1936 	}
1937 }
1938 
1939 static u32 acpi_scan_check_dep(acpi_handle handle, bool check_dep)
1940 {
1941 	struct acpi_handle_list dep_devices;
1942 	acpi_status status;
1943 	u32 count;
1944 	int i;
1945 
1946 	/*
1947 	 * Check for _HID here to avoid deferring the enumeration of:
1948 	 * 1. PCI devices.
1949 	 * 2. ACPI nodes describing USB ports.
1950 	 * Still, checking for _HID catches more then just these cases ...
1951 	 */
1952 	if (!check_dep || !acpi_has_method(handle, "_DEP") ||
1953 	    !acpi_has_method(handle, "_HID"))
1954 		return 0;
1955 
1956 	status = acpi_evaluate_reference(handle, "_DEP", NULL, &dep_devices);
1957 	if (ACPI_FAILURE(status)) {
1958 		acpi_handle_debug(handle, "Failed to evaluate _DEP.\n");
1959 		return 0;
1960 	}
1961 
1962 	for (count = 0, i = 0; i < dep_devices.count; i++) {
1963 		struct acpi_device_info *info;
1964 		struct acpi_dep_data *dep;
1965 		bool skip;
1966 
1967 		status = acpi_get_object_info(dep_devices.handles[i], &info);
1968 		if (ACPI_FAILURE(status)) {
1969 			acpi_handle_debug(handle, "Error reading _DEP device info\n");
1970 			continue;
1971 		}
1972 
1973 		skip = acpi_info_matches_ids(info, acpi_ignore_dep_ids);
1974 		kfree(info);
1975 
1976 		if (skip)
1977 			continue;
1978 
1979 		dep = kzalloc(sizeof(*dep), GFP_KERNEL);
1980 		if (!dep)
1981 			continue;
1982 
1983 		count++;
1984 
1985 		dep->supplier = dep_devices.handles[i];
1986 		dep->consumer = handle;
1987 
1988 		mutex_lock(&acpi_dep_list_lock);
1989 		list_add_tail(&dep->node , &acpi_dep_list);
1990 		mutex_unlock(&acpi_dep_list_lock);
1991 	}
1992 
1993 	return count;
1994 }
1995 
1996 static bool acpi_bus_scan_second_pass;
1997 
1998 static acpi_status acpi_bus_check_add(acpi_handle handle, bool check_dep,
1999 				      struct acpi_device **adev_p)
2000 {
2001 	struct acpi_device *device = NULL;
2002 	acpi_object_type acpi_type;
2003 	int type;
2004 
2005 	acpi_bus_get_device(handle, &device);
2006 	if (device)
2007 		goto out;
2008 
2009 	if (ACPI_FAILURE(acpi_get_type(handle, &acpi_type)))
2010 		return AE_OK;
2011 
2012 	switch (acpi_type) {
2013 	case ACPI_TYPE_DEVICE:
2014 		if (acpi_device_should_be_hidden(handle))
2015 			return AE_OK;
2016 
2017 		/* Bail out if there are dependencies. */
2018 		if (acpi_scan_check_dep(handle, check_dep) > 0) {
2019 			acpi_bus_scan_second_pass = true;
2020 			return AE_CTRL_DEPTH;
2021 		}
2022 
2023 		fallthrough;
2024 	case ACPI_TYPE_ANY:	/* for ACPI_ROOT_OBJECT */
2025 		type = ACPI_BUS_TYPE_DEVICE;
2026 		break;
2027 
2028 	case ACPI_TYPE_PROCESSOR:
2029 		type = ACPI_BUS_TYPE_PROCESSOR;
2030 		break;
2031 
2032 	case ACPI_TYPE_THERMAL:
2033 		type = ACPI_BUS_TYPE_THERMAL;
2034 		break;
2035 
2036 	case ACPI_TYPE_POWER:
2037 		acpi_add_power_resource(handle);
2038 		fallthrough;
2039 	default:
2040 		return AE_OK;
2041 	}
2042 
2043 	/*
2044 	 * If check_dep is true at this point, the device has no dependencies,
2045 	 * or the creation of the device object would have been postponed above.
2046 	 */
2047 	acpi_add_single_object(&device, handle, type, !check_dep);
2048 	if (!device)
2049 		return AE_CTRL_DEPTH;
2050 
2051 	acpi_scan_init_hotplug(device);
2052 
2053 out:
2054 	if (!*adev_p)
2055 		*adev_p = device;
2056 
2057 	return AE_OK;
2058 }
2059 
2060 static acpi_status acpi_bus_check_add_1(acpi_handle handle, u32 lvl_not_used,
2061 					void *not_used, void **ret_p)
2062 {
2063 	return acpi_bus_check_add(handle, true, (struct acpi_device **)ret_p);
2064 }
2065 
2066 static acpi_status acpi_bus_check_add_2(acpi_handle handle, u32 lvl_not_used,
2067 					void *not_used, void **ret_p)
2068 {
2069 	return acpi_bus_check_add(handle, false, (struct acpi_device **)ret_p);
2070 }
2071 
2072 static void acpi_default_enumeration(struct acpi_device *device)
2073 {
2074 	/*
2075 	 * Do not enumerate devices with enumeration_by_parent flag set as
2076 	 * they will be enumerated by their respective parents.
2077 	 */
2078 	if (!device->flags.enumeration_by_parent) {
2079 		acpi_create_platform_device(device, NULL);
2080 		acpi_device_set_enumerated(device);
2081 	} else {
2082 		blocking_notifier_call_chain(&acpi_reconfig_chain,
2083 					     ACPI_RECONFIG_DEVICE_ADD, device);
2084 	}
2085 }
2086 
2087 static const struct acpi_device_id generic_device_ids[] = {
2088 	{ACPI_DT_NAMESPACE_HID, },
2089 	{"", },
2090 };
2091 
2092 static int acpi_generic_device_attach(struct acpi_device *adev,
2093 				      const struct acpi_device_id *not_used)
2094 {
2095 	/*
2096 	 * Since ACPI_DT_NAMESPACE_HID is the only ID handled here, the test
2097 	 * below can be unconditional.
2098 	 */
2099 	if (adev->data.of_compatible)
2100 		acpi_default_enumeration(adev);
2101 
2102 	return 1;
2103 }
2104 
2105 static struct acpi_scan_handler generic_device_handler = {
2106 	.ids = generic_device_ids,
2107 	.attach = acpi_generic_device_attach,
2108 };
2109 
2110 static int acpi_scan_attach_handler(struct acpi_device *device)
2111 {
2112 	struct acpi_hardware_id *hwid;
2113 	int ret = 0;
2114 
2115 	list_for_each_entry(hwid, &device->pnp.ids, list) {
2116 		const struct acpi_device_id *devid;
2117 		struct acpi_scan_handler *handler;
2118 
2119 		handler = acpi_scan_match_handler(hwid->id, &devid);
2120 		if (handler) {
2121 			if (!handler->attach) {
2122 				device->pnp.type.platform_id = 0;
2123 				continue;
2124 			}
2125 			device->handler = handler;
2126 			ret = handler->attach(device, devid);
2127 			if (ret > 0)
2128 				break;
2129 
2130 			device->handler = NULL;
2131 			if (ret < 0)
2132 				break;
2133 		}
2134 	}
2135 
2136 	return ret;
2137 }
2138 
2139 static void acpi_bus_attach(struct acpi_device *device, bool first_pass)
2140 {
2141 	struct acpi_device *child;
2142 	bool skip = !first_pass && device->flags.visited;
2143 	acpi_handle ejd;
2144 	int ret;
2145 
2146 	if (skip)
2147 		goto ok;
2148 
2149 	if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
2150 		register_dock_dependent_device(device, ejd);
2151 
2152 	acpi_bus_get_status(device);
2153 	/* Skip devices that are not present. */
2154 	if (!acpi_device_is_present(device)) {
2155 		device->flags.initialized = false;
2156 		acpi_device_clear_enumerated(device);
2157 		device->flags.power_manageable = 0;
2158 		return;
2159 	}
2160 	if (device->handler)
2161 		goto ok;
2162 
2163 	if (!device->flags.initialized) {
2164 		device->flags.power_manageable =
2165 			device->power.states[ACPI_STATE_D0].flags.valid;
2166 		if (acpi_bus_init_power(device))
2167 			device->flags.power_manageable = 0;
2168 
2169 		device->flags.initialized = true;
2170 	} else if (device->flags.visited) {
2171 		goto ok;
2172 	}
2173 
2174 	ret = acpi_scan_attach_handler(device);
2175 	if (ret < 0)
2176 		return;
2177 
2178 	device->flags.match_driver = true;
2179 	if (ret > 0 && !device->flags.enumeration_by_parent) {
2180 		acpi_device_set_enumerated(device);
2181 		goto ok;
2182 	}
2183 
2184 	ret = device_attach(&device->dev);
2185 	if (ret < 0)
2186 		return;
2187 
2188 	if (device->pnp.type.platform_id || device->flags.enumeration_by_parent)
2189 		acpi_default_enumeration(device);
2190 	else
2191 		acpi_device_set_enumerated(device);
2192 
2193  ok:
2194 	list_for_each_entry(child, &device->children, node)
2195 		acpi_bus_attach(child, first_pass);
2196 
2197 	if (!skip && device->handler && device->handler->hotplug.notify_online)
2198 		device->handler->hotplug.notify_online(device);
2199 }
2200 
2201 static int acpi_dev_get_first_consumer_dev_cb(struct acpi_dep_data *dep, void *data)
2202 {
2203 	struct acpi_device *adev;
2204 
2205 	adev = acpi_bus_get_acpi_device(dep->consumer);
2206 	if (adev) {
2207 		*(struct acpi_device **)data = adev;
2208 		return 1;
2209 	}
2210 	/* Continue parsing if the device object is not present. */
2211 	return 0;
2212 }
2213 
2214 struct acpi_scan_clear_dep_work {
2215 	struct work_struct work;
2216 	struct acpi_device *adev;
2217 };
2218 
2219 static void acpi_scan_clear_dep_fn(struct work_struct *work)
2220 {
2221 	struct acpi_scan_clear_dep_work *cdw;
2222 
2223 	cdw = container_of(work, struct acpi_scan_clear_dep_work, work);
2224 
2225 	acpi_scan_lock_acquire();
2226 	acpi_bus_attach(cdw->adev, true);
2227 	acpi_scan_lock_release();
2228 
2229 	acpi_dev_put(cdw->adev);
2230 	kfree(cdw);
2231 }
2232 
2233 static bool acpi_scan_clear_dep_queue(struct acpi_device *adev)
2234 {
2235 	struct acpi_scan_clear_dep_work *cdw;
2236 
2237 	if (adev->dep_unmet)
2238 		return false;
2239 
2240 	cdw = kmalloc(sizeof(*cdw), GFP_KERNEL);
2241 	if (!cdw)
2242 		return false;
2243 
2244 	cdw->adev = adev;
2245 	INIT_WORK(&cdw->work, acpi_scan_clear_dep_fn);
2246 	/*
2247 	 * Since the work function may block on the lock until the entire
2248 	 * initial enumeration of devices is complete, put it into the unbound
2249 	 * workqueue.
2250 	 */
2251 	queue_work(system_unbound_wq, &cdw->work);
2252 
2253 	return true;
2254 }
2255 
2256 static int acpi_scan_clear_dep(struct acpi_dep_data *dep, void *data)
2257 {
2258 	struct acpi_device *adev = acpi_bus_get_acpi_device(dep->consumer);
2259 
2260 	if (adev) {
2261 		adev->dep_unmet--;
2262 		if (!acpi_scan_clear_dep_queue(adev))
2263 			acpi_dev_put(adev);
2264 	}
2265 
2266 	list_del(&dep->node);
2267 	kfree(dep);
2268 
2269 	return 0;
2270 }
2271 
2272 /**
2273  * acpi_walk_dep_device_list - Apply a callback to every entry in acpi_dep_list
2274  * @handle:	The ACPI handle of the supplier device
2275  * @callback:	Pointer to the callback function to apply
2276  * @data:	Pointer to some data to pass to the callback
2277  *
2278  * The return value of the callback determines this function's behaviour. If 0
2279  * is returned we continue to iterate over acpi_dep_list. If a positive value
2280  * is returned then the loop is broken but this function returns 0. If a
2281  * negative value is returned by the callback then the loop is broken and that
2282  * value is returned as the final error.
2283  */
2284 static int acpi_walk_dep_device_list(acpi_handle handle,
2285 				int (*callback)(struct acpi_dep_data *, void *),
2286 				void *data)
2287 {
2288 	struct acpi_dep_data *dep, *tmp;
2289 	int ret = 0;
2290 
2291 	mutex_lock(&acpi_dep_list_lock);
2292 	list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
2293 		if (dep->supplier == handle) {
2294 			ret = callback(dep, data);
2295 			if (ret)
2296 				break;
2297 		}
2298 	}
2299 	mutex_unlock(&acpi_dep_list_lock);
2300 
2301 	return ret > 0 ? 0 : ret;
2302 }
2303 
2304 /**
2305  * acpi_dev_clear_dependencies - Inform consumers that the device is now active
2306  * @supplier: Pointer to the supplier &struct acpi_device
2307  *
2308  * Clear dependencies on the given device.
2309  */
2310 void acpi_dev_clear_dependencies(struct acpi_device *supplier)
2311 {
2312 	acpi_walk_dep_device_list(supplier->handle, acpi_scan_clear_dep, NULL);
2313 }
2314 EXPORT_SYMBOL_GPL(acpi_dev_clear_dependencies);
2315 
2316 /**
2317  * acpi_dev_get_first_consumer_dev - Return ACPI device dependent on @supplier
2318  * @supplier: Pointer to the dependee device
2319  *
2320  * Returns the first &struct acpi_device which declares itself dependent on
2321  * @supplier via the _DEP buffer, parsed from the acpi_dep_list.
2322  *
2323  * The caller is responsible for putting the reference to adev when it is no
2324  * longer needed.
2325  */
2326 struct acpi_device *acpi_dev_get_first_consumer_dev(struct acpi_device *supplier)
2327 {
2328 	struct acpi_device *adev = NULL;
2329 
2330 	acpi_walk_dep_device_list(supplier->handle,
2331 				  acpi_dev_get_first_consumer_dev_cb, &adev);
2332 
2333 	return adev;
2334 }
2335 EXPORT_SYMBOL_GPL(acpi_dev_get_first_consumer_dev);
2336 
2337 /**
2338  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
2339  * @handle: Root of the namespace scope to scan.
2340  *
2341  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
2342  * found devices.
2343  *
2344  * If no devices were found, -ENODEV is returned, but it does not mean that
2345  * there has been a real error.  There just have been no suitable ACPI objects
2346  * in the table trunk from which the kernel could create a device and add an
2347  * appropriate driver.
2348  *
2349  * Must be called under acpi_scan_lock.
2350  */
2351 int acpi_bus_scan(acpi_handle handle)
2352 {
2353 	struct acpi_device *device = NULL;
2354 
2355 	acpi_bus_scan_second_pass = false;
2356 
2357 	/* Pass 1: Avoid enumerating devices with missing dependencies. */
2358 
2359 	if (ACPI_SUCCESS(acpi_bus_check_add(handle, true, &device)))
2360 		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2361 				    acpi_bus_check_add_1, NULL, NULL,
2362 				    (void **)&device);
2363 
2364 	if (!device)
2365 		return -ENODEV;
2366 
2367 	acpi_bus_attach(device, true);
2368 
2369 	if (!acpi_bus_scan_second_pass)
2370 		return 0;
2371 
2372 	/* Pass 2: Enumerate all of the remaining devices. */
2373 
2374 	device = NULL;
2375 
2376 	if (ACPI_SUCCESS(acpi_bus_check_add(handle, false, &device)))
2377 		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2378 				    acpi_bus_check_add_2, NULL, NULL,
2379 				    (void **)&device);
2380 
2381 	acpi_bus_attach(device, false);
2382 
2383 	return 0;
2384 }
2385 EXPORT_SYMBOL(acpi_bus_scan);
2386 
2387 /**
2388  * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
2389  * @adev: Root of the ACPI namespace scope to walk.
2390  *
2391  * Must be called under acpi_scan_lock.
2392  */
2393 void acpi_bus_trim(struct acpi_device *adev)
2394 {
2395 	struct acpi_scan_handler *handler = adev->handler;
2396 	struct acpi_device *child;
2397 
2398 	list_for_each_entry_reverse(child, &adev->children, node)
2399 		acpi_bus_trim(child);
2400 
2401 	adev->flags.match_driver = false;
2402 	if (handler) {
2403 		if (handler->detach)
2404 			handler->detach(adev);
2405 
2406 		adev->handler = NULL;
2407 	} else {
2408 		device_release_driver(&adev->dev);
2409 	}
2410 	/*
2411 	 * Most likely, the device is going away, so put it into D3cold before
2412 	 * that.
2413 	 */
2414 	acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
2415 	adev->flags.initialized = false;
2416 	acpi_device_clear_enumerated(adev);
2417 }
2418 EXPORT_SYMBOL_GPL(acpi_bus_trim);
2419 
2420 int acpi_bus_register_early_device(int type)
2421 {
2422 	struct acpi_device *device = NULL;
2423 	int result;
2424 
2425 	result = acpi_add_single_object(&device, NULL, type, false);
2426 	if (result)
2427 		return result;
2428 
2429 	device->flags.match_driver = true;
2430 	return device_attach(&device->dev);
2431 }
2432 EXPORT_SYMBOL_GPL(acpi_bus_register_early_device);
2433 
2434 static int acpi_bus_scan_fixed(void)
2435 {
2436 	int result = 0;
2437 
2438 	/*
2439 	 * Enumerate all fixed-feature devices.
2440 	 */
2441 	if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2442 		struct acpi_device *device = NULL;
2443 
2444 		result = acpi_add_single_object(&device, NULL,
2445 						ACPI_BUS_TYPE_POWER_BUTTON, false);
2446 		if (result)
2447 			return result;
2448 
2449 		device->flags.match_driver = true;
2450 		result = device_attach(&device->dev);
2451 		if (result < 0)
2452 			return result;
2453 
2454 		device_init_wakeup(&device->dev, true);
2455 	}
2456 
2457 	if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2458 		struct acpi_device *device = NULL;
2459 
2460 		result = acpi_add_single_object(&device, NULL,
2461 						ACPI_BUS_TYPE_SLEEP_BUTTON, false);
2462 		if (result)
2463 			return result;
2464 
2465 		device->flags.match_driver = true;
2466 		result = device_attach(&device->dev);
2467 	}
2468 
2469 	return result < 0 ? result : 0;
2470 }
2471 
2472 static void __init acpi_get_spcr_uart_addr(void)
2473 {
2474 	acpi_status status;
2475 	struct acpi_table_spcr *spcr_ptr;
2476 
2477 	status = acpi_get_table(ACPI_SIG_SPCR, 0,
2478 				(struct acpi_table_header **)&spcr_ptr);
2479 	if (ACPI_FAILURE(status)) {
2480 		pr_warn("STAO table present, but SPCR is missing\n");
2481 		return;
2482 	}
2483 
2484 	spcr_uart_addr = spcr_ptr->serial_port.address;
2485 	acpi_put_table((struct acpi_table_header *)spcr_ptr);
2486 }
2487 
2488 static bool acpi_scan_initialized;
2489 
2490 int __init acpi_scan_init(void)
2491 {
2492 	int result;
2493 	acpi_status status;
2494 	struct acpi_table_stao *stao_ptr;
2495 
2496 	acpi_pci_root_init();
2497 	acpi_pci_link_init();
2498 	acpi_processor_init();
2499 	acpi_platform_init();
2500 	acpi_lpss_init();
2501 	acpi_apd_init();
2502 	acpi_cmos_rtc_init();
2503 	acpi_container_init();
2504 	acpi_memory_hotplug_init();
2505 	acpi_watchdog_init();
2506 	acpi_pnp_init();
2507 	acpi_int340x_thermal_init();
2508 	acpi_amba_init();
2509 	acpi_init_lpit();
2510 
2511 	acpi_scan_add_handler(&generic_device_handler);
2512 
2513 	/*
2514 	 * If there is STAO table, check whether it needs to ignore the UART
2515 	 * device in SPCR table.
2516 	 */
2517 	status = acpi_get_table(ACPI_SIG_STAO, 0,
2518 				(struct acpi_table_header **)&stao_ptr);
2519 	if (ACPI_SUCCESS(status)) {
2520 		if (stao_ptr->header.length > sizeof(struct acpi_table_stao))
2521 			pr_info("STAO Name List not yet supported.\n");
2522 
2523 		if (stao_ptr->ignore_uart)
2524 			acpi_get_spcr_uart_addr();
2525 
2526 		acpi_put_table((struct acpi_table_header *)stao_ptr);
2527 	}
2528 
2529 	acpi_gpe_apply_masked_gpes();
2530 	acpi_update_all_gpes();
2531 
2532 	/*
2533 	 * Although we call __add_memory() that is documented to require the
2534 	 * device_hotplug_lock, it is not necessary here because this is an
2535 	 * early code when userspace or any other code path cannot trigger
2536 	 * hotplug/hotunplug operations.
2537 	 */
2538 	mutex_lock(&acpi_scan_lock);
2539 	/*
2540 	 * Enumerate devices in the ACPI namespace.
2541 	 */
2542 	result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2543 	if (result)
2544 		goto out;
2545 
2546 	result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2547 	if (result)
2548 		goto out;
2549 
2550 	/* Fixed feature devices do not exist on HW-reduced platform */
2551 	if (!acpi_gbl_reduced_hardware) {
2552 		result = acpi_bus_scan_fixed();
2553 		if (result) {
2554 			acpi_detach_data(acpi_root->handle,
2555 					 acpi_scan_drop_device);
2556 			acpi_device_del(acpi_root);
2557 			acpi_bus_put_acpi_device(acpi_root);
2558 			goto out;
2559 		}
2560 	}
2561 
2562 	acpi_turn_off_unused_power_resources();
2563 
2564 	acpi_scan_initialized = true;
2565 
2566  out:
2567 	mutex_unlock(&acpi_scan_lock);
2568 	return result;
2569 }
2570 
2571 static struct acpi_probe_entry *ape;
2572 static int acpi_probe_count;
2573 static DEFINE_MUTEX(acpi_probe_mutex);
2574 
2575 static int __init acpi_match_madt(union acpi_subtable_headers *header,
2576 				  const unsigned long end)
2577 {
2578 	if (!ape->subtable_valid || ape->subtable_valid(&header->common, ape))
2579 		if (!ape->probe_subtbl(header, end))
2580 			acpi_probe_count++;
2581 
2582 	return 0;
2583 }
2584 
2585 int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr)
2586 {
2587 	int count = 0;
2588 
2589 	if (acpi_disabled)
2590 		return 0;
2591 
2592 	mutex_lock(&acpi_probe_mutex);
2593 	for (ape = ap_head; nr; ape++, nr--) {
2594 		if (ACPI_COMPARE_NAMESEG(ACPI_SIG_MADT, ape->id)) {
2595 			acpi_probe_count = 0;
2596 			acpi_table_parse_madt(ape->type, acpi_match_madt, 0);
2597 			count += acpi_probe_count;
2598 		} else {
2599 			int res;
2600 			res = acpi_table_parse(ape->id, ape->probe_table);
2601 			if (!res)
2602 				count++;
2603 		}
2604 	}
2605 	mutex_unlock(&acpi_probe_mutex);
2606 
2607 	return count;
2608 }
2609 
2610 static void acpi_table_events_fn(struct work_struct *work)
2611 {
2612 	acpi_scan_lock_acquire();
2613 	acpi_bus_scan(ACPI_ROOT_OBJECT);
2614 	acpi_scan_lock_release();
2615 
2616 	kfree(work);
2617 }
2618 
2619 void acpi_scan_table_notify(void)
2620 {
2621 	struct work_struct *work;
2622 
2623 	if (!acpi_scan_initialized)
2624 		return;
2625 
2626 	work = kmalloc(sizeof(*work), GFP_KERNEL);
2627 	if (!work)
2628 		return;
2629 
2630 	INIT_WORK(work, acpi_table_events_fn);
2631 	schedule_work(work);
2632 }
2633 
2634 int acpi_reconfig_notifier_register(struct notifier_block *nb)
2635 {
2636 	return blocking_notifier_chain_register(&acpi_reconfig_chain, nb);
2637 }
2638 EXPORT_SYMBOL(acpi_reconfig_notifier_register);
2639 
2640 int acpi_reconfig_notifier_unregister(struct notifier_block *nb)
2641 {
2642 	return blocking_notifier_chain_unregister(&acpi_reconfig_chain, nb);
2643 }
2644 EXPORT_SYMBOL(acpi_reconfig_notifier_unregister);
2645