xref: /linux/drivers/acpi/scan.c (revision 26fbb4c8c7c3ee9a4c3b4de555a8587b5a19154e)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * scan.c - support for transforming the ACPI namespace into individual objects
4  */
5 
6 #include <linux/module.h>
7 #include <linux/init.h>
8 #include <linux/slab.h>
9 #include <linux/kernel.h>
10 #include <linux/acpi.h>
11 #include <linux/acpi_iort.h>
12 #include <linux/signal.h>
13 #include <linux/kthread.h>
14 #include <linux/dmi.h>
15 #include <linux/nls.h>
16 #include <linux/dma-map-ops.h>
17 #include <linux/platform_data/x86/apple.h>
18 #include <linux/pgtable.h>
19 
20 #include "internal.h"
21 
22 #define _COMPONENT		ACPI_BUS_COMPONENT
23 ACPI_MODULE_NAME("scan");
24 extern struct acpi_device *acpi_root;
25 
26 #define ACPI_BUS_CLASS			"system_bus"
27 #define ACPI_BUS_HID			"LNXSYBUS"
28 #define ACPI_BUS_DEVICE_NAME		"System Bus"
29 
30 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
31 
32 #define INVALID_ACPI_HANDLE	((acpi_handle)empty_zero_page)
33 
34 static const char *dummy_hid = "device";
35 
36 static LIST_HEAD(acpi_dep_list);
37 static DEFINE_MUTEX(acpi_dep_list_lock);
38 LIST_HEAD(acpi_bus_id_list);
39 static DEFINE_MUTEX(acpi_scan_lock);
40 static LIST_HEAD(acpi_scan_handlers_list);
41 DEFINE_MUTEX(acpi_device_lock);
42 LIST_HEAD(acpi_wakeup_device_list);
43 static DEFINE_MUTEX(acpi_hp_context_lock);
44 
45 /*
46  * The UART device described by the SPCR table is the only object which needs
47  * special-casing. Everything else is covered by ACPI namespace paths in STAO
48  * table.
49  */
50 static u64 spcr_uart_addr;
51 
52 struct acpi_dep_data {
53 	struct list_head node;
54 	acpi_handle supplier;
55 	acpi_handle consumer;
56 };
57 
58 void acpi_scan_lock_acquire(void)
59 {
60 	mutex_lock(&acpi_scan_lock);
61 }
62 EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
63 
64 void acpi_scan_lock_release(void)
65 {
66 	mutex_unlock(&acpi_scan_lock);
67 }
68 EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
69 
70 void acpi_lock_hp_context(void)
71 {
72 	mutex_lock(&acpi_hp_context_lock);
73 }
74 
75 void acpi_unlock_hp_context(void)
76 {
77 	mutex_unlock(&acpi_hp_context_lock);
78 }
79 
80 void acpi_initialize_hp_context(struct acpi_device *adev,
81 				struct acpi_hotplug_context *hp,
82 				int (*notify)(struct acpi_device *, u32),
83 				void (*uevent)(struct acpi_device *, u32))
84 {
85 	acpi_lock_hp_context();
86 	hp->notify = notify;
87 	hp->uevent = uevent;
88 	acpi_set_hp_context(adev, hp);
89 	acpi_unlock_hp_context();
90 }
91 EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
92 
93 int acpi_scan_add_handler(struct acpi_scan_handler *handler)
94 {
95 	if (!handler)
96 		return -EINVAL;
97 
98 	list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
99 	return 0;
100 }
101 
102 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
103 				       const char *hotplug_profile_name)
104 {
105 	int error;
106 
107 	error = acpi_scan_add_handler(handler);
108 	if (error)
109 		return error;
110 
111 	acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
112 	return 0;
113 }
114 
115 bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
116 {
117 	struct acpi_device_physical_node *pn;
118 	bool offline = true;
119 	char *envp[] = { "EVENT=offline", NULL };
120 
121 	/*
122 	 * acpi_container_offline() calls this for all of the container's
123 	 * children under the container's physical_node_lock lock.
124 	 */
125 	mutex_lock_nested(&adev->physical_node_lock, SINGLE_DEPTH_NESTING);
126 
127 	list_for_each_entry(pn, &adev->physical_node_list, node)
128 		if (device_supports_offline(pn->dev) && !pn->dev->offline) {
129 			if (uevent)
130 				kobject_uevent_env(&pn->dev->kobj, KOBJ_CHANGE, envp);
131 
132 			offline = false;
133 			break;
134 		}
135 
136 	mutex_unlock(&adev->physical_node_lock);
137 	return offline;
138 }
139 
140 static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
141 				    void **ret_p)
142 {
143 	struct acpi_device *device = NULL;
144 	struct acpi_device_physical_node *pn;
145 	bool second_pass = (bool)data;
146 	acpi_status status = AE_OK;
147 
148 	if (acpi_bus_get_device(handle, &device))
149 		return AE_OK;
150 
151 	if (device->handler && !device->handler->hotplug.enabled) {
152 		*ret_p = &device->dev;
153 		return AE_SUPPORT;
154 	}
155 
156 	mutex_lock(&device->physical_node_lock);
157 
158 	list_for_each_entry(pn, &device->physical_node_list, node) {
159 		int ret;
160 
161 		if (second_pass) {
162 			/* Skip devices offlined by the first pass. */
163 			if (pn->put_online)
164 				continue;
165 		} else {
166 			pn->put_online = false;
167 		}
168 		ret = device_offline(pn->dev);
169 		if (ret >= 0) {
170 			pn->put_online = !ret;
171 		} else {
172 			*ret_p = pn->dev;
173 			if (second_pass) {
174 				status = AE_ERROR;
175 				break;
176 			}
177 		}
178 	}
179 
180 	mutex_unlock(&device->physical_node_lock);
181 
182 	return status;
183 }
184 
185 static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
186 				   void **ret_p)
187 {
188 	struct acpi_device *device = NULL;
189 	struct acpi_device_physical_node *pn;
190 
191 	if (acpi_bus_get_device(handle, &device))
192 		return AE_OK;
193 
194 	mutex_lock(&device->physical_node_lock);
195 
196 	list_for_each_entry(pn, &device->physical_node_list, node)
197 		if (pn->put_online) {
198 			device_online(pn->dev);
199 			pn->put_online = false;
200 		}
201 
202 	mutex_unlock(&device->physical_node_lock);
203 
204 	return AE_OK;
205 }
206 
207 static int acpi_scan_try_to_offline(struct acpi_device *device)
208 {
209 	acpi_handle handle = device->handle;
210 	struct device *errdev = NULL;
211 	acpi_status status;
212 
213 	/*
214 	 * Carry out two passes here and ignore errors in the first pass,
215 	 * because if the devices in question are memory blocks and
216 	 * CONFIG_MEMCG is set, one of the blocks may hold data structures
217 	 * that the other blocks depend on, but it is not known in advance which
218 	 * block holds them.
219 	 *
220 	 * If the first pass is successful, the second one isn't needed, though.
221 	 */
222 	status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
223 				     NULL, acpi_bus_offline, (void *)false,
224 				     (void **)&errdev);
225 	if (status == AE_SUPPORT) {
226 		dev_warn(errdev, "Offline disabled.\n");
227 		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
228 				    acpi_bus_online, NULL, NULL, NULL);
229 		return -EPERM;
230 	}
231 	acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
232 	if (errdev) {
233 		errdev = NULL;
234 		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
235 				    NULL, acpi_bus_offline, (void *)true,
236 				    (void **)&errdev);
237 		if (!errdev)
238 			acpi_bus_offline(handle, 0, (void *)true,
239 					 (void **)&errdev);
240 
241 		if (errdev) {
242 			dev_warn(errdev, "Offline failed.\n");
243 			acpi_bus_online(handle, 0, NULL, NULL);
244 			acpi_walk_namespace(ACPI_TYPE_ANY, handle,
245 					    ACPI_UINT32_MAX, acpi_bus_online,
246 					    NULL, NULL, NULL);
247 			return -EBUSY;
248 		}
249 	}
250 	return 0;
251 }
252 
253 static int acpi_scan_hot_remove(struct acpi_device *device)
254 {
255 	acpi_handle handle = device->handle;
256 	unsigned long long sta;
257 	acpi_status status;
258 
259 	if (device->handler && device->handler->hotplug.demand_offline) {
260 		if (!acpi_scan_is_offline(device, true))
261 			return -EBUSY;
262 	} else {
263 		int error = acpi_scan_try_to_offline(device);
264 		if (error)
265 			return error;
266 	}
267 
268 	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
269 		"Hot-removing device %s...\n", dev_name(&device->dev)));
270 
271 	acpi_bus_trim(device);
272 
273 	acpi_evaluate_lck(handle, 0);
274 	/*
275 	 * TBD: _EJD support.
276 	 */
277 	status = acpi_evaluate_ej0(handle);
278 	if (status == AE_NOT_FOUND)
279 		return -ENODEV;
280 	else if (ACPI_FAILURE(status))
281 		return -EIO;
282 
283 	/*
284 	 * Verify if eject was indeed successful.  If not, log an error
285 	 * message.  No need to call _OST since _EJ0 call was made OK.
286 	 */
287 	status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
288 	if (ACPI_FAILURE(status)) {
289 		acpi_handle_warn(handle,
290 			"Status check after eject failed (0x%x)\n", status);
291 	} else if (sta & ACPI_STA_DEVICE_ENABLED) {
292 		acpi_handle_warn(handle,
293 			"Eject incomplete - status 0x%llx\n", sta);
294 	}
295 
296 	return 0;
297 }
298 
299 static int acpi_scan_device_not_present(struct acpi_device *adev)
300 {
301 	if (!acpi_device_enumerated(adev)) {
302 		dev_warn(&adev->dev, "Still not present\n");
303 		return -EALREADY;
304 	}
305 	acpi_bus_trim(adev);
306 	return 0;
307 }
308 
309 static int acpi_scan_device_check(struct acpi_device *adev)
310 {
311 	int error;
312 
313 	acpi_bus_get_status(adev);
314 	if (adev->status.present || adev->status.functional) {
315 		/*
316 		 * This function is only called for device objects for which
317 		 * matching scan handlers exist.  The only situation in which
318 		 * the scan handler is not attached to this device object yet
319 		 * is when the device has just appeared (either it wasn't
320 		 * present at all before or it was removed and then added
321 		 * again).
322 		 */
323 		if (adev->handler) {
324 			dev_warn(&adev->dev, "Already enumerated\n");
325 			return -EALREADY;
326 		}
327 		error = acpi_bus_scan(adev->handle);
328 		if (error) {
329 			dev_warn(&adev->dev, "Namespace scan failure\n");
330 			return error;
331 		}
332 		if (!adev->handler) {
333 			dev_warn(&adev->dev, "Enumeration failure\n");
334 			error = -ENODEV;
335 		}
336 	} else {
337 		error = acpi_scan_device_not_present(adev);
338 	}
339 	return error;
340 }
341 
342 static int acpi_scan_bus_check(struct acpi_device *adev)
343 {
344 	struct acpi_scan_handler *handler = adev->handler;
345 	struct acpi_device *child;
346 	int error;
347 
348 	acpi_bus_get_status(adev);
349 	if (!(adev->status.present || adev->status.functional)) {
350 		acpi_scan_device_not_present(adev);
351 		return 0;
352 	}
353 	if (handler && handler->hotplug.scan_dependent)
354 		return handler->hotplug.scan_dependent(adev);
355 
356 	error = acpi_bus_scan(adev->handle);
357 	if (error) {
358 		dev_warn(&adev->dev, "Namespace scan failure\n");
359 		return error;
360 	}
361 	list_for_each_entry(child, &adev->children, node) {
362 		error = acpi_scan_bus_check(child);
363 		if (error)
364 			return error;
365 	}
366 	return 0;
367 }
368 
369 static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type)
370 {
371 	switch (type) {
372 	case ACPI_NOTIFY_BUS_CHECK:
373 		return acpi_scan_bus_check(adev);
374 	case ACPI_NOTIFY_DEVICE_CHECK:
375 		return acpi_scan_device_check(adev);
376 	case ACPI_NOTIFY_EJECT_REQUEST:
377 	case ACPI_OST_EC_OSPM_EJECT:
378 		if (adev->handler && !adev->handler->hotplug.enabled) {
379 			dev_info(&adev->dev, "Eject disabled\n");
380 			return -EPERM;
381 		}
382 		acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST,
383 				  ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
384 		return acpi_scan_hot_remove(adev);
385 	}
386 	return -EINVAL;
387 }
388 
389 void acpi_device_hotplug(struct acpi_device *adev, u32 src)
390 {
391 	u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
392 	int error = -ENODEV;
393 
394 	lock_device_hotplug();
395 	mutex_lock(&acpi_scan_lock);
396 
397 	/*
398 	 * The device object's ACPI handle cannot become invalid as long as we
399 	 * are holding acpi_scan_lock, but it might have become invalid before
400 	 * that lock was acquired.
401 	 */
402 	if (adev->handle == INVALID_ACPI_HANDLE)
403 		goto err_out;
404 
405 	if (adev->flags.is_dock_station) {
406 		error = dock_notify(adev, src);
407 	} else if (adev->flags.hotplug_notify) {
408 		error = acpi_generic_hotplug_event(adev, src);
409 	} else {
410 		int (*notify)(struct acpi_device *, u32);
411 
412 		acpi_lock_hp_context();
413 		notify = adev->hp ? adev->hp->notify : NULL;
414 		acpi_unlock_hp_context();
415 		/*
416 		 * There may be additional notify handlers for device objects
417 		 * without the .event() callback, so ignore them here.
418 		 */
419 		if (notify)
420 			error = notify(adev, src);
421 		else
422 			goto out;
423 	}
424 	switch (error) {
425 	case 0:
426 		ost_code = ACPI_OST_SC_SUCCESS;
427 		break;
428 	case -EPERM:
429 		ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
430 		break;
431 	case -EBUSY:
432 		ost_code = ACPI_OST_SC_DEVICE_BUSY;
433 		break;
434 	default:
435 		ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
436 		break;
437 	}
438 
439  err_out:
440 	acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
441 
442  out:
443 	acpi_bus_put_acpi_device(adev);
444 	mutex_unlock(&acpi_scan_lock);
445 	unlock_device_hotplug();
446 }
447 
448 static void acpi_free_power_resources_lists(struct acpi_device *device)
449 {
450 	int i;
451 
452 	if (device->wakeup.flags.valid)
453 		acpi_power_resources_list_free(&device->wakeup.resources);
454 
455 	if (!device->power.flags.power_resources)
456 		return;
457 
458 	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
459 		struct acpi_device_power_state *ps = &device->power.states[i];
460 		acpi_power_resources_list_free(&ps->resources);
461 	}
462 }
463 
464 static void acpi_device_release(struct device *dev)
465 {
466 	struct acpi_device *acpi_dev = to_acpi_device(dev);
467 
468 	acpi_free_properties(acpi_dev);
469 	acpi_free_pnp_ids(&acpi_dev->pnp);
470 	acpi_free_power_resources_lists(acpi_dev);
471 	kfree(acpi_dev);
472 }
473 
474 static void acpi_device_del(struct acpi_device *device)
475 {
476 	struct acpi_device_bus_id *acpi_device_bus_id;
477 
478 	mutex_lock(&acpi_device_lock);
479 	if (device->parent)
480 		list_del(&device->node);
481 
482 	list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node)
483 		if (!strcmp(acpi_device_bus_id->bus_id,
484 			    acpi_device_hid(device))) {
485 			if (acpi_device_bus_id->instance_no > 0)
486 				acpi_device_bus_id->instance_no--;
487 			else {
488 				list_del(&acpi_device_bus_id->node);
489 				kfree_const(acpi_device_bus_id->bus_id);
490 				kfree(acpi_device_bus_id);
491 			}
492 			break;
493 		}
494 
495 	list_del(&device->wakeup_list);
496 	mutex_unlock(&acpi_device_lock);
497 
498 	acpi_power_add_remove_device(device, false);
499 	acpi_device_remove_files(device);
500 	if (device->remove)
501 		device->remove(device);
502 
503 	device_del(&device->dev);
504 }
505 
506 static BLOCKING_NOTIFIER_HEAD(acpi_reconfig_chain);
507 
508 static LIST_HEAD(acpi_device_del_list);
509 static DEFINE_MUTEX(acpi_device_del_lock);
510 
511 static void acpi_device_del_work_fn(struct work_struct *work_not_used)
512 {
513 	for (;;) {
514 		struct acpi_device *adev;
515 
516 		mutex_lock(&acpi_device_del_lock);
517 
518 		if (list_empty(&acpi_device_del_list)) {
519 			mutex_unlock(&acpi_device_del_lock);
520 			break;
521 		}
522 		adev = list_first_entry(&acpi_device_del_list,
523 					struct acpi_device, del_list);
524 		list_del(&adev->del_list);
525 
526 		mutex_unlock(&acpi_device_del_lock);
527 
528 		blocking_notifier_call_chain(&acpi_reconfig_chain,
529 					     ACPI_RECONFIG_DEVICE_REMOVE, adev);
530 
531 		acpi_device_del(adev);
532 		/*
533 		 * Drop references to all power resources that might have been
534 		 * used by the device.
535 		 */
536 		acpi_power_transition(adev, ACPI_STATE_D3_COLD);
537 		put_device(&adev->dev);
538 	}
539 }
540 
541 /**
542  * acpi_scan_drop_device - Drop an ACPI device object.
543  * @handle: Handle of an ACPI namespace node, not used.
544  * @context: Address of the ACPI device object to drop.
545  *
546  * This is invoked by acpi_ns_delete_node() during the removal of the ACPI
547  * namespace node the device object pointed to by @context is attached to.
548  *
549  * The unregistration is carried out asynchronously to avoid running
550  * acpi_device_del() under the ACPICA's namespace mutex and the list is used to
551  * ensure the correct ordering (the device objects must be unregistered in the
552  * same order in which the corresponding namespace nodes are deleted).
553  */
554 static void acpi_scan_drop_device(acpi_handle handle, void *context)
555 {
556 	static DECLARE_WORK(work, acpi_device_del_work_fn);
557 	struct acpi_device *adev = context;
558 
559 	mutex_lock(&acpi_device_del_lock);
560 
561 	/*
562 	 * Use the ACPI hotplug workqueue which is ordered, so this work item
563 	 * won't run after any hotplug work items submitted subsequently.  That
564 	 * prevents attempts to register device objects identical to those being
565 	 * deleted from happening concurrently (such attempts result from
566 	 * hotplug events handled via the ACPI hotplug workqueue).  It also will
567 	 * run after all of the work items submitted previosuly, which helps
568 	 * those work items to ensure that they are not accessing stale device
569 	 * objects.
570 	 */
571 	if (list_empty(&acpi_device_del_list))
572 		acpi_queue_hotplug_work(&work);
573 
574 	list_add_tail(&adev->del_list, &acpi_device_del_list);
575 	/* Make acpi_ns_validate_handle() return NULL for this handle. */
576 	adev->handle = INVALID_ACPI_HANDLE;
577 
578 	mutex_unlock(&acpi_device_del_lock);
579 }
580 
581 static int acpi_get_device_data(acpi_handle handle, struct acpi_device **device,
582 				void (*callback)(void *))
583 {
584 	acpi_status status;
585 
586 	if (!device)
587 		return -EINVAL;
588 
589 	*device = NULL;
590 
591 	status = acpi_get_data_full(handle, acpi_scan_drop_device,
592 				    (void **)device, callback);
593 	if (ACPI_FAILURE(status) || !*device) {
594 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
595 				  handle));
596 		return -ENODEV;
597 	}
598 	return 0;
599 }
600 
601 int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
602 {
603 	return acpi_get_device_data(handle, device, NULL);
604 }
605 EXPORT_SYMBOL(acpi_bus_get_device);
606 
607 static void get_acpi_device(void *dev)
608 {
609 	if (dev)
610 		get_device(&((struct acpi_device *)dev)->dev);
611 }
612 
613 struct acpi_device *acpi_bus_get_acpi_device(acpi_handle handle)
614 {
615 	struct acpi_device *adev = NULL;
616 
617 	acpi_get_device_data(handle, &adev, get_acpi_device);
618 	return adev;
619 }
620 
621 void acpi_bus_put_acpi_device(struct acpi_device *adev)
622 {
623 	put_device(&adev->dev);
624 }
625 
626 int acpi_device_add(struct acpi_device *device,
627 		    void (*release)(struct device *))
628 {
629 	int result;
630 	struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
631 	int found = 0;
632 
633 	if (device->handle) {
634 		acpi_status status;
635 
636 		status = acpi_attach_data(device->handle, acpi_scan_drop_device,
637 					  device);
638 		if (ACPI_FAILURE(status)) {
639 			acpi_handle_err(device->handle,
640 					"Unable to attach device data\n");
641 			return -ENODEV;
642 		}
643 	}
644 
645 	/*
646 	 * Linkage
647 	 * -------
648 	 * Link this device to its parent and siblings.
649 	 */
650 	INIT_LIST_HEAD(&device->children);
651 	INIT_LIST_HEAD(&device->node);
652 	INIT_LIST_HEAD(&device->wakeup_list);
653 	INIT_LIST_HEAD(&device->physical_node_list);
654 	INIT_LIST_HEAD(&device->del_list);
655 	mutex_init(&device->physical_node_lock);
656 
657 	new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
658 	if (!new_bus_id) {
659 		pr_err(PREFIX "Memory allocation error\n");
660 		result = -ENOMEM;
661 		goto err_detach;
662 	}
663 
664 	mutex_lock(&acpi_device_lock);
665 	/*
666 	 * Find suitable bus_id and instance number in acpi_bus_id_list
667 	 * If failed, create one and link it into acpi_bus_id_list
668 	 */
669 	list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
670 		if (!strcmp(acpi_device_bus_id->bus_id,
671 			    acpi_device_hid(device))) {
672 			acpi_device_bus_id->instance_no++;
673 			found = 1;
674 			kfree(new_bus_id);
675 			break;
676 		}
677 	}
678 	if (!found) {
679 		acpi_device_bus_id = new_bus_id;
680 		acpi_device_bus_id->bus_id =
681 			kstrdup_const(acpi_device_hid(device), GFP_KERNEL);
682 		if (!acpi_device_bus_id->bus_id) {
683 			pr_err(PREFIX "Memory allocation error for bus id\n");
684 			result = -ENOMEM;
685 			goto err_free_new_bus_id;
686 		}
687 
688 		acpi_device_bus_id->instance_no = 0;
689 		list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
690 	}
691 	dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
692 
693 	if (device->parent)
694 		list_add_tail(&device->node, &device->parent->children);
695 
696 	if (device->wakeup.flags.valid)
697 		list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
698 	mutex_unlock(&acpi_device_lock);
699 
700 	if (device->parent)
701 		device->dev.parent = &device->parent->dev;
702 	device->dev.bus = &acpi_bus_type;
703 	device->dev.release = release;
704 	result = device_add(&device->dev);
705 	if (result) {
706 		dev_err(&device->dev, "Error registering device\n");
707 		goto err;
708 	}
709 
710 	result = acpi_device_setup_files(device);
711 	if (result)
712 		printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
713 		       dev_name(&device->dev));
714 
715 	return 0;
716 
717  err:
718 	mutex_lock(&acpi_device_lock);
719 	if (device->parent)
720 		list_del(&device->node);
721 	list_del(&device->wakeup_list);
722 
723  err_free_new_bus_id:
724 	if (!found)
725 		kfree(new_bus_id);
726 
727 	mutex_unlock(&acpi_device_lock);
728 
729  err_detach:
730 	acpi_detach_data(device->handle, acpi_scan_drop_device);
731 	return result;
732 }
733 
734 /* --------------------------------------------------------------------------
735                                  Device Enumeration
736    -------------------------------------------------------------------------- */
737 static bool acpi_info_matches_ids(struct acpi_device_info *info,
738 				  const char * const ids[])
739 {
740 	struct acpi_pnp_device_id_list *cid_list = NULL;
741 	int i;
742 
743 	if (!(info->valid & ACPI_VALID_HID))
744 		return false;
745 
746 	if (info->valid & ACPI_VALID_CID)
747 		cid_list = &info->compatible_id_list;
748 
749 	for (i = 0; ids[i]; i++) {
750 		int j;
751 
752 		if (!strcmp(info->hardware_id.string, ids[i]))
753 			return true;
754 
755 		if (!cid_list)
756 			continue;
757 
758 		for (j = 0; j < cid_list->count; j++) {
759 			if (!strcmp(cid_list->ids[j].string, ids[i]))
760 				return true;
761 		}
762 	}
763 
764 	return false;
765 }
766 
767 /* List of HIDs for which we ignore matching ACPI devices, when checking _DEP lists. */
768 static const char * const acpi_ignore_dep_ids[] = {
769 	"PNP0D80", /* Windows-compatible System Power Management Controller */
770 	"INT33BD", /* Intel Baytrail Mailbox Device */
771 	NULL
772 };
773 
774 static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
775 {
776 	struct acpi_device *device = NULL;
777 	acpi_status status;
778 
779 	/*
780 	 * Fixed hardware devices do not appear in the namespace and do not
781 	 * have handles, but we fabricate acpi_devices for them, so we have
782 	 * to deal with them specially.
783 	 */
784 	if (!handle)
785 		return acpi_root;
786 
787 	do {
788 		status = acpi_get_parent(handle, &handle);
789 		if (ACPI_FAILURE(status))
790 			return status == AE_NULL_ENTRY ? NULL : acpi_root;
791 	} while (acpi_bus_get_device(handle, &device));
792 	return device;
793 }
794 
795 acpi_status
796 acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
797 {
798 	acpi_status status;
799 	acpi_handle tmp;
800 	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
801 	union acpi_object *obj;
802 
803 	status = acpi_get_handle(handle, "_EJD", &tmp);
804 	if (ACPI_FAILURE(status))
805 		return status;
806 
807 	status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
808 	if (ACPI_SUCCESS(status)) {
809 		obj = buffer.pointer;
810 		status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
811 					 ejd);
812 		kfree(buffer.pointer);
813 	}
814 	return status;
815 }
816 EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
817 
818 static int acpi_bus_extract_wakeup_device_power_package(struct acpi_device *dev)
819 {
820 	acpi_handle handle = dev->handle;
821 	struct acpi_device_wakeup *wakeup = &dev->wakeup;
822 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
823 	union acpi_object *package = NULL;
824 	union acpi_object *element = NULL;
825 	acpi_status status;
826 	int err = -ENODATA;
827 
828 	INIT_LIST_HEAD(&wakeup->resources);
829 
830 	/* _PRW */
831 	status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
832 	if (ACPI_FAILURE(status)) {
833 		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
834 		return err;
835 	}
836 
837 	package = (union acpi_object *)buffer.pointer;
838 
839 	if (!package || package->package.count < 2)
840 		goto out;
841 
842 	element = &(package->package.elements[0]);
843 	if (!element)
844 		goto out;
845 
846 	if (element->type == ACPI_TYPE_PACKAGE) {
847 		if ((element->package.count < 2) ||
848 		    (element->package.elements[0].type !=
849 		     ACPI_TYPE_LOCAL_REFERENCE)
850 		    || (element->package.elements[1].type != ACPI_TYPE_INTEGER))
851 			goto out;
852 
853 		wakeup->gpe_device =
854 		    element->package.elements[0].reference.handle;
855 		wakeup->gpe_number =
856 		    (u32) element->package.elements[1].integer.value;
857 	} else if (element->type == ACPI_TYPE_INTEGER) {
858 		wakeup->gpe_device = NULL;
859 		wakeup->gpe_number = element->integer.value;
860 	} else {
861 		goto out;
862 	}
863 
864 	element = &(package->package.elements[1]);
865 	if (element->type != ACPI_TYPE_INTEGER)
866 		goto out;
867 
868 	wakeup->sleep_state = element->integer.value;
869 
870 	err = acpi_extract_power_resources(package, 2, &wakeup->resources);
871 	if (err)
872 		goto out;
873 
874 	if (!list_empty(&wakeup->resources)) {
875 		int sleep_state;
876 
877 		err = acpi_power_wakeup_list_init(&wakeup->resources,
878 						  &sleep_state);
879 		if (err) {
880 			acpi_handle_warn(handle, "Retrieving current states "
881 					 "of wakeup power resources failed\n");
882 			acpi_power_resources_list_free(&wakeup->resources);
883 			goto out;
884 		}
885 		if (sleep_state < wakeup->sleep_state) {
886 			acpi_handle_warn(handle, "Overriding _PRW sleep state "
887 					 "(S%d) by S%d from power resources\n",
888 					 (int)wakeup->sleep_state, sleep_state);
889 			wakeup->sleep_state = sleep_state;
890 		}
891 	}
892 
893  out:
894 	kfree(buffer.pointer);
895 	return err;
896 }
897 
898 static bool acpi_wakeup_gpe_init(struct acpi_device *device)
899 {
900 	static const struct acpi_device_id button_device_ids[] = {
901 		{"PNP0C0C", 0},		/* Power button */
902 		{"PNP0C0D", 0},		/* Lid */
903 		{"PNP0C0E", 0},		/* Sleep button */
904 		{"", 0},
905 	};
906 	struct acpi_device_wakeup *wakeup = &device->wakeup;
907 	acpi_status status;
908 
909 	wakeup->flags.notifier_present = 0;
910 
911 	/* Power button, Lid switch always enable wakeup */
912 	if (!acpi_match_device_ids(device, button_device_ids)) {
913 		if (!acpi_match_device_ids(device, &button_device_ids[1])) {
914 			/* Do not use Lid/sleep button for S5 wakeup */
915 			if (wakeup->sleep_state == ACPI_STATE_S5)
916 				wakeup->sleep_state = ACPI_STATE_S4;
917 		}
918 		acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
919 		device_set_wakeup_capable(&device->dev, true);
920 		return true;
921 	}
922 
923 	status = acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
924 					 wakeup->gpe_number);
925 	return ACPI_SUCCESS(status);
926 }
927 
928 static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
929 {
930 	int err;
931 
932 	/* Presence of _PRW indicates wake capable */
933 	if (!acpi_has_method(device->handle, "_PRW"))
934 		return;
935 
936 	err = acpi_bus_extract_wakeup_device_power_package(device);
937 	if (err) {
938 		dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
939 		return;
940 	}
941 
942 	device->wakeup.flags.valid = acpi_wakeup_gpe_init(device);
943 	device->wakeup.prepare_count = 0;
944 	/*
945 	 * Call _PSW/_DSW object to disable its ability to wake the sleeping
946 	 * system for the ACPI device with the _PRW object.
947 	 * The _PSW object is deprecated in ACPI 3.0 and is replaced by _DSW.
948 	 * So it is necessary to call _DSW object first. Only when it is not
949 	 * present will the _PSW object used.
950 	 */
951 	err = acpi_device_sleep_wake(device, 0, 0, 0);
952 	if (err)
953 		pr_debug("error in _DSW or _PSW evaluation\n");
954 }
955 
956 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
957 {
958 	struct acpi_device_power_state *ps = &device->power.states[state];
959 	char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
960 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
961 	acpi_status status;
962 
963 	INIT_LIST_HEAD(&ps->resources);
964 
965 	/* Evaluate "_PRx" to get referenced power resources */
966 	status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
967 	if (ACPI_SUCCESS(status)) {
968 		union acpi_object *package = buffer.pointer;
969 
970 		if (buffer.length && package
971 		    && package->type == ACPI_TYPE_PACKAGE
972 		    && package->package.count)
973 			acpi_extract_power_resources(package, 0, &ps->resources);
974 
975 		ACPI_FREE(buffer.pointer);
976 	}
977 
978 	/* Evaluate "_PSx" to see if we can do explicit sets */
979 	pathname[2] = 'S';
980 	if (acpi_has_method(device->handle, pathname))
981 		ps->flags.explicit_set = 1;
982 
983 	/* State is valid if there are means to put the device into it. */
984 	if (!list_empty(&ps->resources) || ps->flags.explicit_set)
985 		ps->flags.valid = 1;
986 
987 	ps->power = -1;		/* Unknown - driver assigned */
988 	ps->latency = -1;	/* Unknown - driver assigned */
989 }
990 
991 static void acpi_bus_get_power_flags(struct acpi_device *device)
992 {
993 	u32 i;
994 
995 	/* Presence of _PS0|_PR0 indicates 'power manageable' */
996 	if (!acpi_has_method(device->handle, "_PS0") &&
997 	    !acpi_has_method(device->handle, "_PR0"))
998 		return;
999 
1000 	device->flags.power_manageable = 1;
1001 
1002 	/*
1003 	 * Power Management Flags
1004 	 */
1005 	if (acpi_has_method(device->handle, "_PSC"))
1006 		device->power.flags.explicit_get = 1;
1007 
1008 	if (acpi_has_method(device->handle, "_IRC"))
1009 		device->power.flags.inrush_current = 1;
1010 
1011 	if (acpi_has_method(device->handle, "_DSW"))
1012 		device->power.flags.dsw_present = 1;
1013 
1014 	/*
1015 	 * Enumerate supported power management states
1016 	 */
1017 	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
1018 		acpi_bus_init_power_state(device, i);
1019 
1020 	INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
1021 
1022 	/* Set the defaults for D0 and D3hot (always supported). */
1023 	device->power.states[ACPI_STATE_D0].flags.valid = 1;
1024 	device->power.states[ACPI_STATE_D0].power = 100;
1025 	device->power.states[ACPI_STATE_D3_HOT].flags.valid = 1;
1026 
1027 	/*
1028 	 * Use power resources only if the D0 list of them is populated, because
1029 	 * some platforms may provide _PR3 only to indicate D3cold support and
1030 	 * in those cases the power resources list returned by it may be bogus.
1031 	 */
1032 	if (!list_empty(&device->power.states[ACPI_STATE_D0].resources)) {
1033 		device->power.flags.power_resources = 1;
1034 		/*
1035 		 * D3cold is supported if the D3hot list of power resources is
1036 		 * not empty.
1037 		 */
1038 		if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources))
1039 			device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
1040 	}
1041 
1042 	if (acpi_bus_init_power(device))
1043 		device->flags.power_manageable = 0;
1044 }
1045 
1046 static void acpi_bus_get_flags(struct acpi_device *device)
1047 {
1048 	/* Presence of _STA indicates 'dynamic_status' */
1049 	if (acpi_has_method(device->handle, "_STA"))
1050 		device->flags.dynamic_status = 1;
1051 
1052 	/* Presence of _RMV indicates 'removable' */
1053 	if (acpi_has_method(device->handle, "_RMV"))
1054 		device->flags.removable = 1;
1055 
1056 	/* Presence of _EJD|_EJ0 indicates 'ejectable' */
1057 	if (acpi_has_method(device->handle, "_EJD") ||
1058 	    acpi_has_method(device->handle, "_EJ0"))
1059 		device->flags.ejectable = 1;
1060 }
1061 
1062 static void acpi_device_get_busid(struct acpi_device *device)
1063 {
1064 	char bus_id[5] = { '?', 0 };
1065 	struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
1066 	int i = 0;
1067 
1068 	/*
1069 	 * Bus ID
1070 	 * ------
1071 	 * The device's Bus ID is simply the object name.
1072 	 * TBD: Shouldn't this value be unique (within the ACPI namespace)?
1073 	 */
1074 	if (ACPI_IS_ROOT_DEVICE(device)) {
1075 		strcpy(device->pnp.bus_id, "ACPI");
1076 		return;
1077 	}
1078 
1079 	switch (device->device_type) {
1080 	case ACPI_BUS_TYPE_POWER_BUTTON:
1081 		strcpy(device->pnp.bus_id, "PWRF");
1082 		break;
1083 	case ACPI_BUS_TYPE_SLEEP_BUTTON:
1084 		strcpy(device->pnp.bus_id, "SLPF");
1085 		break;
1086 	case ACPI_BUS_TYPE_ECDT_EC:
1087 		strcpy(device->pnp.bus_id, "ECDT");
1088 		break;
1089 	default:
1090 		acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
1091 		/* Clean up trailing underscores (if any) */
1092 		for (i = 3; i > 1; i--) {
1093 			if (bus_id[i] == '_')
1094 				bus_id[i] = '\0';
1095 			else
1096 				break;
1097 		}
1098 		strcpy(device->pnp.bus_id, bus_id);
1099 		break;
1100 	}
1101 }
1102 
1103 /*
1104  * acpi_ata_match - see if an acpi object is an ATA device
1105  *
1106  * If an acpi object has one of the ACPI ATA methods defined,
1107  * then we can safely call it an ATA device.
1108  */
1109 bool acpi_ata_match(acpi_handle handle)
1110 {
1111 	return acpi_has_method(handle, "_GTF") ||
1112 	       acpi_has_method(handle, "_GTM") ||
1113 	       acpi_has_method(handle, "_STM") ||
1114 	       acpi_has_method(handle, "_SDD");
1115 }
1116 
1117 /*
1118  * acpi_bay_match - see if an acpi object is an ejectable driver bay
1119  *
1120  * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
1121  * then we can safely call it an ejectable drive bay
1122  */
1123 bool acpi_bay_match(acpi_handle handle)
1124 {
1125 	acpi_handle phandle;
1126 
1127 	if (!acpi_has_method(handle, "_EJ0"))
1128 		return false;
1129 	if (acpi_ata_match(handle))
1130 		return true;
1131 	if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
1132 		return false;
1133 
1134 	return acpi_ata_match(phandle);
1135 }
1136 
1137 bool acpi_device_is_battery(struct acpi_device *adev)
1138 {
1139 	struct acpi_hardware_id *hwid;
1140 
1141 	list_for_each_entry(hwid, &adev->pnp.ids, list)
1142 		if (!strcmp("PNP0C0A", hwid->id))
1143 			return true;
1144 
1145 	return false;
1146 }
1147 
1148 static bool is_ejectable_bay(struct acpi_device *adev)
1149 {
1150 	acpi_handle handle = adev->handle;
1151 
1152 	if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
1153 		return true;
1154 
1155 	return acpi_bay_match(handle);
1156 }
1157 
1158 /*
1159  * acpi_dock_match - see if an acpi object has a _DCK method
1160  */
1161 bool acpi_dock_match(acpi_handle handle)
1162 {
1163 	return acpi_has_method(handle, "_DCK");
1164 }
1165 
1166 static acpi_status
1167 acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
1168 			  void **return_value)
1169 {
1170 	long *cap = context;
1171 
1172 	if (acpi_has_method(handle, "_BCM") &&
1173 	    acpi_has_method(handle, "_BCL")) {
1174 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight "
1175 				  "support\n"));
1176 		*cap |= ACPI_VIDEO_BACKLIGHT;
1177 		/* We have backlight support, no need to scan further */
1178 		return AE_CTRL_TERMINATE;
1179 	}
1180 	return 0;
1181 }
1182 
1183 /* Returns true if the ACPI object is a video device which can be
1184  * handled by video.ko.
1185  * The device will get a Linux specific CID added in scan.c to
1186  * identify the device as an ACPI graphics device
1187  * Be aware that the graphics device may not be physically present
1188  * Use acpi_video_get_capabilities() to detect general ACPI video
1189  * capabilities of present cards
1190  */
1191 long acpi_is_video_device(acpi_handle handle)
1192 {
1193 	long video_caps = 0;
1194 
1195 	/* Is this device able to support video switching ? */
1196 	if (acpi_has_method(handle, "_DOD") || acpi_has_method(handle, "_DOS"))
1197 		video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
1198 
1199 	/* Is this device able to retrieve a video ROM ? */
1200 	if (acpi_has_method(handle, "_ROM"))
1201 		video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
1202 
1203 	/* Is this device able to configure which video head to be POSTed ? */
1204 	if (acpi_has_method(handle, "_VPO") &&
1205 	    acpi_has_method(handle, "_GPD") &&
1206 	    acpi_has_method(handle, "_SPD"))
1207 		video_caps |= ACPI_VIDEO_DEVICE_POSTING;
1208 
1209 	/* Only check for backlight functionality if one of the above hit. */
1210 	if (video_caps)
1211 		acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
1212 				    ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
1213 				    &video_caps, NULL);
1214 
1215 	return video_caps;
1216 }
1217 EXPORT_SYMBOL(acpi_is_video_device);
1218 
1219 const char *acpi_device_hid(struct acpi_device *device)
1220 {
1221 	struct acpi_hardware_id *hid;
1222 
1223 	if (list_empty(&device->pnp.ids))
1224 		return dummy_hid;
1225 
1226 	hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
1227 	return hid->id;
1228 }
1229 EXPORT_SYMBOL(acpi_device_hid);
1230 
1231 static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
1232 {
1233 	struct acpi_hardware_id *id;
1234 
1235 	id = kmalloc(sizeof(*id), GFP_KERNEL);
1236 	if (!id)
1237 		return;
1238 
1239 	id->id = kstrdup_const(dev_id, GFP_KERNEL);
1240 	if (!id->id) {
1241 		kfree(id);
1242 		return;
1243 	}
1244 
1245 	list_add_tail(&id->list, &pnp->ids);
1246 	pnp->type.hardware_id = 1;
1247 }
1248 
1249 /*
1250  * Old IBM workstations have a DSDT bug wherein the SMBus object
1251  * lacks the SMBUS01 HID and the methods do not have the necessary "_"
1252  * prefix.  Work around this.
1253  */
1254 static bool acpi_ibm_smbus_match(acpi_handle handle)
1255 {
1256 	char node_name[ACPI_PATH_SEGMENT_LENGTH];
1257 	struct acpi_buffer path = { sizeof(node_name), node_name };
1258 
1259 	if (!dmi_name_in_vendors("IBM"))
1260 		return false;
1261 
1262 	/* Look for SMBS object */
1263 	if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
1264 	    strcmp("SMBS", path.pointer))
1265 		return false;
1266 
1267 	/* Does it have the necessary (but misnamed) methods? */
1268 	if (acpi_has_method(handle, "SBI") &&
1269 	    acpi_has_method(handle, "SBR") &&
1270 	    acpi_has_method(handle, "SBW"))
1271 		return true;
1272 
1273 	return false;
1274 }
1275 
1276 static bool acpi_object_is_system_bus(acpi_handle handle)
1277 {
1278 	acpi_handle tmp;
1279 
1280 	if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
1281 	    tmp == handle)
1282 		return true;
1283 	if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
1284 	    tmp == handle)
1285 		return true;
1286 
1287 	return false;
1288 }
1289 
1290 static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
1291 				int device_type, struct acpi_device_info *info)
1292 {
1293 	struct acpi_pnp_device_id_list *cid_list;
1294 	int i;
1295 
1296 	switch (device_type) {
1297 	case ACPI_BUS_TYPE_DEVICE:
1298 		if (handle == ACPI_ROOT_OBJECT) {
1299 			acpi_add_id(pnp, ACPI_SYSTEM_HID);
1300 			break;
1301 		}
1302 
1303 		if (!info) {
1304 			pr_err(PREFIX "%s: Error reading device info\n",
1305 					__func__);
1306 			return;
1307 		}
1308 
1309 		if (info->valid & ACPI_VALID_HID) {
1310 			acpi_add_id(pnp, info->hardware_id.string);
1311 			pnp->type.platform_id = 1;
1312 		}
1313 		if (info->valid & ACPI_VALID_CID) {
1314 			cid_list = &info->compatible_id_list;
1315 			for (i = 0; i < cid_list->count; i++)
1316 				acpi_add_id(pnp, cid_list->ids[i].string);
1317 		}
1318 		if (info->valid & ACPI_VALID_ADR) {
1319 			pnp->bus_address = info->address;
1320 			pnp->type.bus_address = 1;
1321 		}
1322 		if (info->valid & ACPI_VALID_UID)
1323 			pnp->unique_id = kstrdup(info->unique_id.string,
1324 							GFP_KERNEL);
1325 		if (info->valid & ACPI_VALID_CLS)
1326 			acpi_add_id(pnp, info->class_code.string);
1327 
1328 		/*
1329 		 * Some devices don't reliably have _HIDs & _CIDs, so add
1330 		 * synthetic HIDs to make sure drivers can find them.
1331 		 */
1332 		if (acpi_is_video_device(handle))
1333 			acpi_add_id(pnp, ACPI_VIDEO_HID);
1334 		else if (acpi_bay_match(handle))
1335 			acpi_add_id(pnp, ACPI_BAY_HID);
1336 		else if (acpi_dock_match(handle))
1337 			acpi_add_id(pnp, ACPI_DOCK_HID);
1338 		else if (acpi_ibm_smbus_match(handle))
1339 			acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
1340 		else if (list_empty(&pnp->ids) &&
1341 			 acpi_object_is_system_bus(handle)) {
1342 			/* \_SB, \_TZ, LNXSYBUS */
1343 			acpi_add_id(pnp, ACPI_BUS_HID);
1344 			strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
1345 			strcpy(pnp->device_class, ACPI_BUS_CLASS);
1346 		}
1347 
1348 		break;
1349 	case ACPI_BUS_TYPE_POWER:
1350 		acpi_add_id(pnp, ACPI_POWER_HID);
1351 		break;
1352 	case ACPI_BUS_TYPE_PROCESSOR:
1353 		acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
1354 		break;
1355 	case ACPI_BUS_TYPE_THERMAL:
1356 		acpi_add_id(pnp, ACPI_THERMAL_HID);
1357 		break;
1358 	case ACPI_BUS_TYPE_POWER_BUTTON:
1359 		acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
1360 		break;
1361 	case ACPI_BUS_TYPE_SLEEP_BUTTON:
1362 		acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
1363 		break;
1364 	case ACPI_BUS_TYPE_ECDT_EC:
1365 		acpi_add_id(pnp, ACPI_ECDT_HID);
1366 		break;
1367 	}
1368 }
1369 
1370 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
1371 {
1372 	struct acpi_hardware_id *id, *tmp;
1373 
1374 	list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
1375 		kfree_const(id->id);
1376 		kfree(id);
1377 	}
1378 	kfree(pnp->unique_id);
1379 }
1380 
1381 /**
1382  * acpi_dma_supported - Check DMA support for the specified device.
1383  * @adev: The pointer to acpi device
1384  *
1385  * Return false if DMA is not supported. Otherwise, return true
1386  */
1387 bool acpi_dma_supported(struct acpi_device *adev)
1388 {
1389 	if (!adev)
1390 		return false;
1391 
1392 	if (adev->flags.cca_seen)
1393 		return true;
1394 
1395 	/*
1396 	* Per ACPI 6.0 sec 6.2.17, assume devices can do cache-coherent
1397 	* DMA on "Intel platforms".  Presumably that includes all x86 and
1398 	* ia64, and other arches will set CONFIG_ACPI_CCA_REQUIRED=y.
1399 	*/
1400 	if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1401 		return true;
1402 
1403 	return false;
1404 }
1405 
1406 /**
1407  * acpi_get_dma_attr - Check the supported DMA attr for the specified device.
1408  * @adev: The pointer to acpi device
1409  *
1410  * Return enum dev_dma_attr.
1411  */
1412 enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
1413 {
1414 	if (!acpi_dma_supported(adev))
1415 		return DEV_DMA_NOT_SUPPORTED;
1416 
1417 	if (adev->flags.coherent_dma)
1418 		return DEV_DMA_COHERENT;
1419 	else
1420 		return DEV_DMA_NON_COHERENT;
1421 }
1422 
1423 /**
1424  * acpi_dma_get_range() - Get device DMA parameters.
1425  *
1426  * @dev: device to configure
1427  * @dma_addr: pointer device DMA address result
1428  * @offset: pointer to the DMA offset result
1429  * @size: pointer to DMA range size result
1430  *
1431  * Evaluate DMA regions and return respectively DMA region start, offset
1432  * and size in dma_addr, offset and size on parsing success; it does not
1433  * update the passed in values on failure.
1434  *
1435  * Return 0 on success, < 0 on failure.
1436  */
1437 int acpi_dma_get_range(struct device *dev, u64 *dma_addr, u64 *offset,
1438 		       u64 *size)
1439 {
1440 	struct acpi_device *adev;
1441 	LIST_HEAD(list);
1442 	struct resource_entry *rentry;
1443 	int ret;
1444 	struct device *dma_dev = dev;
1445 	u64 len, dma_start = U64_MAX, dma_end = 0, dma_offset = 0;
1446 
1447 	/*
1448 	 * Walk the device tree chasing an ACPI companion with a _DMA
1449 	 * object while we go. Stop if we find a device with an ACPI
1450 	 * companion containing a _DMA method.
1451 	 */
1452 	do {
1453 		adev = ACPI_COMPANION(dma_dev);
1454 		if (adev && acpi_has_method(adev->handle, METHOD_NAME__DMA))
1455 			break;
1456 
1457 		dma_dev = dma_dev->parent;
1458 	} while (dma_dev);
1459 
1460 	if (!dma_dev)
1461 		return -ENODEV;
1462 
1463 	if (!acpi_has_method(adev->handle, METHOD_NAME__CRS)) {
1464 		acpi_handle_warn(adev->handle, "_DMA is valid only if _CRS is present\n");
1465 		return -EINVAL;
1466 	}
1467 
1468 	ret = acpi_dev_get_dma_resources(adev, &list);
1469 	if (ret > 0) {
1470 		list_for_each_entry(rentry, &list, node) {
1471 			if (dma_offset && rentry->offset != dma_offset) {
1472 				ret = -EINVAL;
1473 				dev_warn(dma_dev, "Can't handle multiple windows with different offsets\n");
1474 				goto out;
1475 			}
1476 			dma_offset = rentry->offset;
1477 
1478 			/* Take lower and upper limits */
1479 			if (rentry->res->start < dma_start)
1480 				dma_start = rentry->res->start;
1481 			if (rentry->res->end > dma_end)
1482 				dma_end = rentry->res->end;
1483 		}
1484 
1485 		if (dma_start >= dma_end) {
1486 			ret = -EINVAL;
1487 			dev_dbg(dma_dev, "Invalid DMA regions configuration\n");
1488 			goto out;
1489 		}
1490 
1491 		*dma_addr = dma_start - dma_offset;
1492 		len = dma_end - dma_start;
1493 		*size = max(len, len + 1);
1494 		*offset = dma_offset;
1495 	}
1496  out:
1497 	acpi_dev_free_resource_list(&list);
1498 
1499 	return ret >= 0 ? 0 : ret;
1500 }
1501 
1502 /**
1503  * acpi_dma_configure_id - Set-up DMA configuration for the device.
1504  * @dev: The pointer to the device
1505  * @attr: device dma attributes
1506  * @input_id: input device id const value pointer
1507  */
1508 int acpi_dma_configure_id(struct device *dev, enum dev_dma_attr attr,
1509 			  const u32 *input_id)
1510 {
1511 	const struct iommu_ops *iommu;
1512 	u64 dma_addr = 0, size = 0;
1513 
1514 	if (attr == DEV_DMA_NOT_SUPPORTED) {
1515 		set_dma_ops(dev, &dma_dummy_ops);
1516 		return 0;
1517 	}
1518 
1519 	iort_dma_setup(dev, &dma_addr, &size);
1520 
1521 	iommu = iort_iommu_configure_id(dev, input_id);
1522 	if (PTR_ERR(iommu) == -EPROBE_DEFER)
1523 		return -EPROBE_DEFER;
1524 
1525 	arch_setup_dma_ops(dev, dma_addr, size,
1526 				iommu, attr == DEV_DMA_COHERENT);
1527 
1528 	return 0;
1529 }
1530 EXPORT_SYMBOL_GPL(acpi_dma_configure_id);
1531 
1532 static void acpi_init_coherency(struct acpi_device *adev)
1533 {
1534 	unsigned long long cca = 0;
1535 	acpi_status status;
1536 	struct acpi_device *parent = adev->parent;
1537 
1538 	if (parent && parent->flags.cca_seen) {
1539 		/*
1540 		 * From ACPI spec, OSPM will ignore _CCA if an ancestor
1541 		 * already saw one.
1542 		 */
1543 		adev->flags.cca_seen = 1;
1544 		cca = parent->flags.coherent_dma;
1545 	} else {
1546 		status = acpi_evaluate_integer(adev->handle, "_CCA",
1547 					       NULL, &cca);
1548 		if (ACPI_SUCCESS(status))
1549 			adev->flags.cca_seen = 1;
1550 		else if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
1551 			/*
1552 			 * If architecture does not specify that _CCA is
1553 			 * required for DMA-able devices (e.g. x86),
1554 			 * we default to _CCA=1.
1555 			 */
1556 			cca = 1;
1557 		else
1558 			acpi_handle_debug(adev->handle,
1559 					  "ACPI device is missing _CCA.\n");
1560 	}
1561 
1562 	adev->flags.coherent_dma = cca;
1563 }
1564 
1565 static int acpi_check_serial_bus_slave(struct acpi_resource *ares, void *data)
1566 {
1567 	bool *is_serial_bus_slave_p = data;
1568 
1569 	if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
1570 		return 1;
1571 
1572 	*is_serial_bus_slave_p = true;
1573 
1574 	 /* no need to do more checking */
1575 	return -1;
1576 }
1577 
1578 static bool acpi_is_indirect_io_slave(struct acpi_device *device)
1579 {
1580 	struct acpi_device *parent = device->parent;
1581 	static const struct acpi_device_id indirect_io_hosts[] = {
1582 		{"HISI0191", 0},
1583 		{}
1584 	};
1585 
1586 	return parent && !acpi_match_device_ids(parent, indirect_io_hosts);
1587 }
1588 
1589 static bool acpi_device_enumeration_by_parent(struct acpi_device *device)
1590 {
1591 	struct list_head resource_list;
1592 	bool is_serial_bus_slave = false;
1593 	/*
1594 	 * These devices have multiple I2cSerialBus resources and an i2c-client
1595 	 * must be instantiated for each, each with its own i2c_device_id.
1596 	 * Normally we only instantiate an i2c-client for the first resource,
1597 	 * using the ACPI HID as id. These special cases are handled by the
1598 	 * drivers/platform/x86/i2c-multi-instantiate.c driver, which knows
1599 	 * which i2c_device_id to use for each resource.
1600 	 */
1601 	static const struct acpi_device_id i2c_multi_instantiate_ids[] = {
1602 		{"BSG1160", },
1603 		{"BSG2150", },
1604 		{"INT33FE", },
1605 		{"INT3515", },
1606 		{}
1607 	};
1608 
1609 	if (acpi_is_indirect_io_slave(device))
1610 		return true;
1611 
1612 	/* Macs use device properties in lieu of _CRS resources */
1613 	if (x86_apple_machine &&
1614 	    (fwnode_property_present(&device->fwnode, "spiSclkPeriod") ||
1615 	     fwnode_property_present(&device->fwnode, "i2cAddress") ||
1616 	     fwnode_property_present(&device->fwnode, "baud")))
1617 		return true;
1618 
1619 	/* Instantiate a pdev for the i2c-multi-instantiate drv to bind to */
1620 	if (!acpi_match_device_ids(device, i2c_multi_instantiate_ids))
1621 		return false;
1622 
1623 	INIT_LIST_HEAD(&resource_list);
1624 	acpi_dev_get_resources(device, &resource_list,
1625 			       acpi_check_serial_bus_slave,
1626 			       &is_serial_bus_slave);
1627 	acpi_dev_free_resource_list(&resource_list);
1628 
1629 	return is_serial_bus_slave;
1630 }
1631 
1632 void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
1633 			     int type, unsigned long long sta,
1634 			     struct acpi_device_info *info)
1635 {
1636 	INIT_LIST_HEAD(&device->pnp.ids);
1637 	device->device_type = type;
1638 	device->handle = handle;
1639 	device->parent = acpi_bus_get_parent(handle);
1640 	fwnode_init(&device->fwnode, &acpi_device_fwnode_ops);
1641 	acpi_set_device_status(device, sta);
1642 	acpi_device_get_busid(device);
1643 	acpi_set_pnp_ids(handle, &device->pnp, type, info);
1644 	acpi_init_properties(device);
1645 	acpi_bus_get_flags(device);
1646 	device->flags.match_driver = false;
1647 	device->flags.initialized = true;
1648 	device->flags.enumeration_by_parent =
1649 		acpi_device_enumeration_by_parent(device);
1650 	acpi_device_clear_enumerated(device);
1651 	device_initialize(&device->dev);
1652 	dev_set_uevent_suppress(&device->dev, true);
1653 	acpi_init_coherency(device);
1654 }
1655 
1656 void acpi_device_add_finalize(struct acpi_device *device)
1657 {
1658 	dev_set_uevent_suppress(&device->dev, false);
1659 	kobject_uevent(&device->dev.kobj, KOBJ_ADD);
1660 }
1661 
1662 static int acpi_add_single_object(struct acpi_device **child,
1663 				  acpi_handle handle, int type,
1664 				  unsigned long long sta)
1665 {
1666 	int result;
1667 	struct acpi_device *device;
1668 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1669 	struct acpi_device_info *info = NULL;
1670 
1671 	if (handle != ACPI_ROOT_OBJECT && type == ACPI_BUS_TYPE_DEVICE)
1672 		acpi_get_object_info(handle, &info);
1673 
1674 	device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
1675 	if (!device) {
1676 		printk(KERN_ERR PREFIX "Memory allocation error\n");
1677 		kfree(info);
1678 		return -ENOMEM;
1679 	}
1680 
1681 	acpi_init_device_object(device, handle, type, sta, info);
1682 	kfree(info);
1683 	/*
1684 	 * For ACPI_BUS_TYPE_DEVICE getting the status is delayed till here so
1685 	 * that we can call acpi_bus_get_status() and use its quirk handling.
1686 	 * Note this must be done before the get power-/wakeup_dev-flags calls.
1687 	 */
1688 	if (type == ACPI_BUS_TYPE_DEVICE)
1689 		if (acpi_bus_get_status(device) < 0)
1690 			acpi_set_device_status(device, 0);
1691 
1692 	acpi_bus_get_power_flags(device);
1693 	acpi_bus_get_wakeup_device_flags(device);
1694 
1695 	result = acpi_device_add(device, acpi_device_release);
1696 	if (result) {
1697 		acpi_device_release(&device->dev);
1698 		return result;
1699 	}
1700 
1701 	acpi_power_add_remove_device(device, true);
1702 	acpi_device_add_finalize(device);
1703 	acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
1704 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
1705 		dev_name(&device->dev), (char *) buffer.pointer,
1706 		device->parent ? dev_name(&device->parent->dev) : "(null)"));
1707 	kfree(buffer.pointer);
1708 	*child = device;
1709 	return 0;
1710 }
1711 
1712 static acpi_status acpi_get_resource_memory(struct acpi_resource *ares,
1713 					    void *context)
1714 {
1715 	struct resource *res = context;
1716 
1717 	if (acpi_dev_resource_memory(ares, res))
1718 		return AE_CTRL_TERMINATE;
1719 
1720 	return AE_OK;
1721 }
1722 
1723 static bool acpi_device_should_be_hidden(acpi_handle handle)
1724 {
1725 	acpi_status status;
1726 	struct resource res;
1727 
1728 	/* Check if it should ignore the UART device */
1729 	if (!(spcr_uart_addr && acpi_has_method(handle, METHOD_NAME__CRS)))
1730 		return false;
1731 
1732 	/*
1733 	 * The UART device described in SPCR table is assumed to have only one
1734 	 * memory resource present. So we only look for the first one here.
1735 	 */
1736 	status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1737 				     acpi_get_resource_memory, &res);
1738 	if (ACPI_FAILURE(status) || res.start != spcr_uart_addr)
1739 		return false;
1740 
1741 	acpi_handle_info(handle, "The UART device @%pa in SPCR table will be hidden\n",
1742 			 &res.start);
1743 
1744 	return true;
1745 }
1746 
1747 static int acpi_bus_type_and_status(acpi_handle handle, int *type,
1748 				    unsigned long long *sta)
1749 {
1750 	acpi_status status;
1751 	acpi_object_type acpi_type;
1752 
1753 	status = acpi_get_type(handle, &acpi_type);
1754 	if (ACPI_FAILURE(status))
1755 		return -ENODEV;
1756 
1757 	switch (acpi_type) {
1758 	case ACPI_TYPE_ANY:		/* for ACPI_ROOT_OBJECT */
1759 	case ACPI_TYPE_DEVICE:
1760 		if (acpi_device_should_be_hidden(handle))
1761 			return -ENODEV;
1762 
1763 		*type = ACPI_BUS_TYPE_DEVICE;
1764 		/*
1765 		 * acpi_add_single_object updates this once we've an acpi_device
1766 		 * so that acpi_bus_get_status' quirk handling can be used.
1767 		 */
1768 		*sta = ACPI_STA_DEFAULT;
1769 		break;
1770 	case ACPI_TYPE_PROCESSOR:
1771 		*type = ACPI_BUS_TYPE_PROCESSOR;
1772 		status = acpi_bus_get_status_handle(handle, sta);
1773 		if (ACPI_FAILURE(status))
1774 			return -ENODEV;
1775 		break;
1776 	case ACPI_TYPE_THERMAL:
1777 		*type = ACPI_BUS_TYPE_THERMAL;
1778 		*sta = ACPI_STA_DEFAULT;
1779 		break;
1780 	case ACPI_TYPE_POWER:
1781 		*type = ACPI_BUS_TYPE_POWER;
1782 		*sta = ACPI_STA_DEFAULT;
1783 		break;
1784 	default:
1785 		return -ENODEV;
1786 	}
1787 
1788 	return 0;
1789 }
1790 
1791 bool acpi_device_is_present(const struct acpi_device *adev)
1792 {
1793 	return adev->status.present || adev->status.functional;
1794 }
1795 
1796 static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
1797 				       const char *idstr,
1798 				       const struct acpi_device_id **matchid)
1799 {
1800 	const struct acpi_device_id *devid;
1801 
1802 	if (handler->match)
1803 		return handler->match(idstr, matchid);
1804 
1805 	for (devid = handler->ids; devid->id[0]; devid++)
1806 		if (!strcmp((char *)devid->id, idstr)) {
1807 			if (matchid)
1808 				*matchid = devid;
1809 
1810 			return true;
1811 		}
1812 
1813 	return false;
1814 }
1815 
1816 static struct acpi_scan_handler *acpi_scan_match_handler(const char *idstr,
1817 					const struct acpi_device_id **matchid)
1818 {
1819 	struct acpi_scan_handler *handler;
1820 
1821 	list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
1822 		if (acpi_scan_handler_matching(handler, idstr, matchid))
1823 			return handler;
1824 
1825 	return NULL;
1826 }
1827 
1828 void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
1829 {
1830 	if (!!hotplug->enabled == !!val)
1831 		return;
1832 
1833 	mutex_lock(&acpi_scan_lock);
1834 
1835 	hotplug->enabled = val;
1836 
1837 	mutex_unlock(&acpi_scan_lock);
1838 }
1839 
1840 static void acpi_scan_init_hotplug(struct acpi_device *adev)
1841 {
1842 	struct acpi_hardware_id *hwid;
1843 
1844 	if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
1845 		acpi_dock_add(adev);
1846 		return;
1847 	}
1848 	list_for_each_entry(hwid, &adev->pnp.ids, list) {
1849 		struct acpi_scan_handler *handler;
1850 
1851 		handler = acpi_scan_match_handler(hwid->id, NULL);
1852 		if (handler) {
1853 			adev->flags.hotplug_notify = true;
1854 			break;
1855 		}
1856 	}
1857 }
1858 
1859 static u32 acpi_scan_check_dep(acpi_handle handle)
1860 {
1861 	struct acpi_handle_list dep_devices;
1862 	acpi_status status;
1863 	u32 count;
1864 	int i;
1865 
1866 	/*
1867 	 * Check for _HID here to avoid deferring the enumeration of:
1868 	 * 1. PCI devices.
1869 	 * 2. ACPI nodes describing USB ports.
1870 	 * Still, checking for _HID catches more then just these cases ...
1871 	 */
1872 	if (!acpi_has_method(handle, "_DEP") || !acpi_has_method(handle, "_HID"))
1873 		return 0;
1874 
1875 	status = acpi_evaluate_reference(handle, "_DEP", NULL, &dep_devices);
1876 	if (ACPI_FAILURE(status)) {
1877 		acpi_handle_debug(handle, "Failed to evaluate _DEP.\n");
1878 		return 0;
1879 	}
1880 
1881 	for (count = 0, i = 0; i < dep_devices.count; i++) {
1882 		struct acpi_device_info *info;
1883 		struct acpi_dep_data *dep;
1884 		bool skip;
1885 
1886 		status = acpi_get_object_info(dep_devices.handles[i], &info);
1887 		if (ACPI_FAILURE(status)) {
1888 			acpi_handle_debug(handle, "Error reading _DEP device info\n");
1889 			continue;
1890 		}
1891 
1892 		skip = acpi_info_matches_ids(info, acpi_ignore_dep_ids);
1893 		kfree(info);
1894 
1895 		if (skip)
1896 			continue;
1897 
1898 		dep = kzalloc(sizeof(*dep), GFP_KERNEL);
1899 		if (!dep)
1900 			continue;
1901 
1902 		count++;
1903 
1904 		dep->supplier = dep_devices.handles[i];
1905 		dep->consumer = handle;
1906 
1907 		mutex_lock(&acpi_dep_list_lock);
1908 		list_add_tail(&dep->node , &acpi_dep_list);
1909 		mutex_unlock(&acpi_dep_list_lock);
1910 	}
1911 
1912 	return count;
1913 }
1914 
1915 static void acpi_scan_dep_init(struct acpi_device *adev)
1916 {
1917 	struct acpi_dep_data *dep;
1918 
1919 	mutex_lock(&acpi_dep_list_lock);
1920 
1921 	list_for_each_entry(dep, &acpi_dep_list, node) {
1922 		if (dep->consumer == adev->handle)
1923 			adev->dep_unmet++;
1924 	}
1925 
1926 	mutex_unlock(&acpi_dep_list_lock);
1927 }
1928 
1929 static bool acpi_bus_scan_second_pass;
1930 
1931 static acpi_status acpi_bus_check_add(acpi_handle handle, bool check_dep,
1932 				      struct acpi_device **adev_p)
1933 {
1934 	struct acpi_device *device = NULL;
1935 	unsigned long long sta;
1936 	int type;
1937 	int result;
1938 
1939 	acpi_bus_get_device(handle, &device);
1940 	if (device)
1941 		goto out;
1942 
1943 	result = acpi_bus_type_and_status(handle, &type, &sta);
1944 	if (result)
1945 		return AE_OK;
1946 
1947 	if (type == ACPI_BUS_TYPE_POWER) {
1948 		acpi_add_power_resource(handle);
1949 		return AE_OK;
1950 	}
1951 
1952 	if (type == ACPI_BUS_TYPE_DEVICE && check_dep) {
1953 		u32 count = acpi_scan_check_dep(handle);
1954 		/* Bail out if the number of recorded dependencies is not 0. */
1955 		if (count > 0) {
1956 			acpi_bus_scan_second_pass = true;
1957 			return AE_CTRL_DEPTH;
1958 		}
1959 	}
1960 
1961 	acpi_add_single_object(&device, handle, type, sta);
1962 	if (!device)
1963 		return AE_CTRL_DEPTH;
1964 
1965 	acpi_scan_init_hotplug(device);
1966 	if (!check_dep)
1967 		acpi_scan_dep_init(device);
1968 
1969 out:
1970 	if (!*adev_p)
1971 		*adev_p = device;
1972 
1973 	return AE_OK;
1974 }
1975 
1976 static acpi_status acpi_bus_check_add_1(acpi_handle handle, u32 lvl_not_used,
1977 					void *not_used, void **ret_p)
1978 {
1979 	return acpi_bus_check_add(handle, true, (struct acpi_device **)ret_p);
1980 }
1981 
1982 static acpi_status acpi_bus_check_add_2(acpi_handle handle, u32 lvl_not_used,
1983 					void *not_used, void **ret_p)
1984 {
1985 	return acpi_bus_check_add(handle, false, (struct acpi_device **)ret_p);
1986 }
1987 
1988 static void acpi_default_enumeration(struct acpi_device *device)
1989 {
1990 	/*
1991 	 * Do not enumerate devices with enumeration_by_parent flag set as
1992 	 * they will be enumerated by their respective parents.
1993 	 */
1994 	if (!device->flags.enumeration_by_parent) {
1995 		acpi_create_platform_device(device, NULL);
1996 		acpi_device_set_enumerated(device);
1997 	} else {
1998 		blocking_notifier_call_chain(&acpi_reconfig_chain,
1999 					     ACPI_RECONFIG_DEVICE_ADD, device);
2000 	}
2001 }
2002 
2003 static const struct acpi_device_id generic_device_ids[] = {
2004 	{ACPI_DT_NAMESPACE_HID, },
2005 	{"", },
2006 };
2007 
2008 static int acpi_generic_device_attach(struct acpi_device *adev,
2009 				      const struct acpi_device_id *not_used)
2010 {
2011 	/*
2012 	 * Since ACPI_DT_NAMESPACE_HID is the only ID handled here, the test
2013 	 * below can be unconditional.
2014 	 */
2015 	if (adev->data.of_compatible)
2016 		acpi_default_enumeration(adev);
2017 
2018 	return 1;
2019 }
2020 
2021 static struct acpi_scan_handler generic_device_handler = {
2022 	.ids = generic_device_ids,
2023 	.attach = acpi_generic_device_attach,
2024 };
2025 
2026 static int acpi_scan_attach_handler(struct acpi_device *device)
2027 {
2028 	struct acpi_hardware_id *hwid;
2029 	int ret = 0;
2030 
2031 	list_for_each_entry(hwid, &device->pnp.ids, list) {
2032 		const struct acpi_device_id *devid;
2033 		struct acpi_scan_handler *handler;
2034 
2035 		handler = acpi_scan_match_handler(hwid->id, &devid);
2036 		if (handler) {
2037 			if (!handler->attach) {
2038 				device->pnp.type.platform_id = 0;
2039 				continue;
2040 			}
2041 			device->handler = handler;
2042 			ret = handler->attach(device, devid);
2043 			if (ret > 0)
2044 				break;
2045 
2046 			device->handler = NULL;
2047 			if (ret < 0)
2048 				break;
2049 		}
2050 	}
2051 
2052 	return ret;
2053 }
2054 
2055 static void acpi_bus_attach(struct acpi_device *device, bool first_pass)
2056 {
2057 	struct acpi_device *child;
2058 	bool skip = !first_pass && device->flags.visited;
2059 	acpi_handle ejd;
2060 	int ret;
2061 
2062 	if (skip)
2063 		goto ok;
2064 
2065 	if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
2066 		register_dock_dependent_device(device, ejd);
2067 
2068 	acpi_bus_get_status(device);
2069 	/* Skip devices that are not present. */
2070 	if (!acpi_device_is_present(device)) {
2071 		device->flags.initialized = false;
2072 		acpi_device_clear_enumerated(device);
2073 		device->flags.power_manageable = 0;
2074 		return;
2075 	}
2076 	if (device->handler)
2077 		goto ok;
2078 
2079 	if (!device->flags.initialized) {
2080 		device->flags.power_manageable =
2081 			device->power.states[ACPI_STATE_D0].flags.valid;
2082 		if (acpi_bus_init_power(device))
2083 			device->flags.power_manageable = 0;
2084 
2085 		device->flags.initialized = true;
2086 	} else if (device->flags.visited) {
2087 		goto ok;
2088 	}
2089 
2090 	ret = acpi_scan_attach_handler(device);
2091 	if (ret < 0)
2092 		return;
2093 
2094 	device->flags.match_driver = true;
2095 	if (ret > 0 && !device->flags.enumeration_by_parent) {
2096 		acpi_device_set_enumerated(device);
2097 		goto ok;
2098 	}
2099 
2100 	ret = device_attach(&device->dev);
2101 	if (ret < 0)
2102 		return;
2103 
2104 	if (device->pnp.type.platform_id || device->flags.enumeration_by_parent)
2105 		acpi_default_enumeration(device);
2106 	else
2107 		acpi_device_set_enumerated(device);
2108 
2109  ok:
2110 	list_for_each_entry(child, &device->children, node)
2111 		acpi_bus_attach(child, first_pass);
2112 
2113 	if (!skip && device->handler && device->handler->hotplug.notify_online)
2114 		device->handler->hotplug.notify_online(device);
2115 }
2116 
2117 void acpi_walk_dep_device_list(acpi_handle handle)
2118 {
2119 	struct acpi_dep_data *dep, *tmp;
2120 	struct acpi_device *adev;
2121 
2122 	mutex_lock(&acpi_dep_list_lock);
2123 	list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
2124 		if (dep->supplier == handle) {
2125 			acpi_bus_get_device(dep->consumer, &adev);
2126 			if (!adev)
2127 				continue;
2128 
2129 			adev->dep_unmet--;
2130 			if (!adev->dep_unmet)
2131 				acpi_bus_attach(adev, true);
2132 
2133 			list_del(&dep->node);
2134 			kfree(dep);
2135 		}
2136 	}
2137 	mutex_unlock(&acpi_dep_list_lock);
2138 }
2139 EXPORT_SYMBOL_GPL(acpi_walk_dep_device_list);
2140 
2141 /**
2142  * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
2143  * @handle: Root of the namespace scope to scan.
2144  *
2145  * Scan a given ACPI tree (probably recently hot-plugged) and create and add
2146  * found devices.
2147  *
2148  * If no devices were found, -ENODEV is returned, but it does not mean that
2149  * there has been a real error.  There just have been no suitable ACPI objects
2150  * in the table trunk from which the kernel could create a device and add an
2151  * appropriate driver.
2152  *
2153  * Must be called under acpi_scan_lock.
2154  */
2155 int acpi_bus_scan(acpi_handle handle)
2156 {
2157 	struct acpi_device *device = NULL;
2158 
2159 	acpi_bus_scan_second_pass = false;
2160 
2161 	/* Pass 1: Avoid enumerating devices with missing dependencies. */
2162 
2163 	if (ACPI_SUCCESS(acpi_bus_check_add(handle, true, &device)))
2164 		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2165 				    acpi_bus_check_add_1, NULL, NULL,
2166 				    (void **)&device);
2167 
2168 	if (!device)
2169 		return -ENODEV;
2170 
2171 	acpi_bus_attach(device, true);
2172 
2173 	if (!acpi_bus_scan_second_pass)
2174 		return 0;
2175 
2176 	/* Pass 2: Enumerate all of the remaining devices. */
2177 
2178 	device = NULL;
2179 
2180 	if (ACPI_SUCCESS(acpi_bus_check_add(handle, false, &device)))
2181 		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
2182 				    acpi_bus_check_add_2, NULL, NULL,
2183 				    (void **)&device);
2184 
2185 	acpi_bus_attach(device, false);
2186 
2187 	return 0;
2188 }
2189 EXPORT_SYMBOL(acpi_bus_scan);
2190 
2191 /**
2192  * acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
2193  * @adev: Root of the ACPI namespace scope to walk.
2194  *
2195  * Must be called under acpi_scan_lock.
2196  */
2197 void acpi_bus_trim(struct acpi_device *adev)
2198 {
2199 	struct acpi_scan_handler *handler = adev->handler;
2200 	struct acpi_device *child;
2201 
2202 	list_for_each_entry_reverse(child, &adev->children, node)
2203 		acpi_bus_trim(child);
2204 
2205 	adev->flags.match_driver = false;
2206 	if (handler) {
2207 		if (handler->detach)
2208 			handler->detach(adev);
2209 
2210 		adev->handler = NULL;
2211 	} else {
2212 		device_release_driver(&adev->dev);
2213 	}
2214 	/*
2215 	 * Most likely, the device is going away, so put it into D3cold before
2216 	 * that.
2217 	 */
2218 	acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
2219 	adev->flags.initialized = false;
2220 	acpi_device_clear_enumerated(adev);
2221 }
2222 EXPORT_SYMBOL_GPL(acpi_bus_trim);
2223 
2224 int acpi_bus_register_early_device(int type)
2225 {
2226 	struct acpi_device *device = NULL;
2227 	int result;
2228 
2229 	result = acpi_add_single_object(&device, NULL,
2230 					type, ACPI_STA_DEFAULT);
2231 	if (result)
2232 		return result;
2233 
2234 	device->flags.match_driver = true;
2235 	return device_attach(&device->dev);
2236 }
2237 EXPORT_SYMBOL_GPL(acpi_bus_register_early_device);
2238 
2239 static int acpi_bus_scan_fixed(void)
2240 {
2241 	int result = 0;
2242 
2243 	/*
2244 	 * Enumerate all fixed-feature devices.
2245 	 */
2246 	if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
2247 		struct acpi_device *device = NULL;
2248 
2249 		result = acpi_add_single_object(&device, NULL,
2250 						ACPI_BUS_TYPE_POWER_BUTTON,
2251 						ACPI_STA_DEFAULT);
2252 		if (result)
2253 			return result;
2254 
2255 		device->flags.match_driver = true;
2256 		result = device_attach(&device->dev);
2257 		if (result < 0)
2258 			return result;
2259 
2260 		device_init_wakeup(&device->dev, true);
2261 	}
2262 
2263 	if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
2264 		struct acpi_device *device = NULL;
2265 
2266 		result = acpi_add_single_object(&device, NULL,
2267 						ACPI_BUS_TYPE_SLEEP_BUTTON,
2268 						ACPI_STA_DEFAULT);
2269 		if (result)
2270 			return result;
2271 
2272 		device->flags.match_driver = true;
2273 		result = device_attach(&device->dev);
2274 	}
2275 
2276 	return result < 0 ? result : 0;
2277 }
2278 
2279 static void __init acpi_get_spcr_uart_addr(void)
2280 {
2281 	acpi_status status;
2282 	struct acpi_table_spcr *spcr_ptr;
2283 
2284 	status = acpi_get_table(ACPI_SIG_SPCR, 0,
2285 				(struct acpi_table_header **)&spcr_ptr);
2286 	if (ACPI_FAILURE(status)) {
2287 		pr_warn(PREFIX "STAO table present, but SPCR is missing\n");
2288 		return;
2289 	}
2290 
2291 	spcr_uart_addr = spcr_ptr->serial_port.address;
2292 	acpi_put_table((struct acpi_table_header *)spcr_ptr);
2293 }
2294 
2295 static bool acpi_scan_initialized;
2296 
2297 int __init acpi_scan_init(void)
2298 {
2299 	int result;
2300 	acpi_status status;
2301 	struct acpi_table_stao *stao_ptr;
2302 
2303 	acpi_pci_root_init();
2304 	acpi_pci_link_init();
2305 	acpi_processor_init();
2306 	acpi_platform_init();
2307 	acpi_lpss_init();
2308 	acpi_apd_init();
2309 	acpi_cmos_rtc_init();
2310 	acpi_container_init();
2311 	acpi_memory_hotplug_init();
2312 	acpi_watchdog_init();
2313 	acpi_pnp_init();
2314 	acpi_int340x_thermal_init();
2315 	acpi_amba_init();
2316 	acpi_init_lpit();
2317 
2318 	acpi_scan_add_handler(&generic_device_handler);
2319 
2320 	/*
2321 	 * If there is STAO table, check whether it needs to ignore the UART
2322 	 * device in SPCR table.
2323 	 */
2324 	status = acpi_get_table(ACPI_SIG_STAO, 0,
2325 				(struct acpi_table_header **)&stao_ptr);
2326 	if (ACPI_SUCCESS(status)) {
2327 		if (stao_ptr->header.length > sizeof(struct acpi_table_stao))
2328 			pr_info(PREFIX "STAO Name List not yet supported.\n");
2329 
2330 		if (stao_ptr->ignore_uart)
2331 			acpi_get_spcr_uart_addr();
2332 
2333 		acpi_put_table((struct acpi_table_header *)stao_ptr);
2334 	}
2335 
2336 	acpi_gpe_apply_masked_gpes();
2337 	acpi_update_all_gpes();
2338 
2339 	/*
2340 	 * Although we call __add_memory() that is documented to require the
2341 	 * device_hotplug_lock, it is not necessary here because this is an
2342 	 * early code when userspace or any other code path cannot trigger
2343 	 * hotplug/hotunplug operations.
2344 	 */
2345 	mutex_lock(&acpi_scan_lock);
2346 	/*
2347 	 * Enumerate devices in the ACPI namespace.
2348 	 */
2349 	result = acpi_bus_scan(ACPI_ROOT_OBJECT);
2350 	if (result)
2351 		goto out;
2352 
2353 	result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
2354 	if (result)
2355 		goto out;
2356 
2357 	/* Fixed feature devices do not exist on HW-reduced platform */
2358 	if (!acpi_gbl_reduced_hardware) {
2359 		result = acpi_bus_scan_fixed();
2360 		if (result) {
2361 			acpi_detach_data(acpi_root->handle,
2362 					 acpi_scan_drop_device);
2363 			acpi_device_del(acpi_root);
2364 			put_device(&acpi_root->dev);
2365 			goto out;
2366 		}
2367 	}
2368 
2369 	acpi_scan_initialized = true;
2370 
2371  out:
2372 	mutex_unlock(&acpi_scan_lock);
2373 	return result;
2374 }
2375 
2376 static struct acpi_probe_entry *ape;
2377 static int acpi_probe_count;
2378 static DEFINE_MUTEX(acpi_probe_mutex);
2379 
2380 static int __init acpi_match_madt(union acpi_subtable_headers *header,
2381 				  const unsigned long end)
2382 {
2383 	if (!ape->subtable_valid || ape->subtable_valid(&header->common, ape))
2384 		if (!ape->probe_subtbl(header, end))
2385 			acpi_probe_count++;
2386 
2387 	return 0;
2388 }
2389 
2390 int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr)
2391 {
2392 	int count = 0;
2393 
2394 	if (acpi_disabled)
2395 		return 0;
2396 
2397 	mutex_lock(&acpi_probe_mutex);
2398 	for (ape = ap_head; nr; ape++, nr--) {
2399 		if (ACPI_COMPARE_NAMESEG(ACPI_SIG_MADT, ape->id)) {
2400 			acpi_probe_count = 0;
2401 			acpi_table_parse_madt(ape->type, acpi_match_madt, 0);
2402 			count += acpi_probe_count;
2403 		} else {
2404 			int res;
2405 			res = acpi_table_parse(ape->id, ape->probe_table);
2406 			if (!res)
2407 				count++;
2408 		}
2409 	}
2410 	mutex_unlock(&acpi_probe_mutex);
2411 
2412 	return count;
2413 }
2414 
2415 struct acpi_table_events_work {
2416 	struct work_struct work;
2417 	void *table;
2418 	u32 event;
2419 };
2420 
2421 static void acpi_table_events_fn(struct work_struct *work)
2422 {
2423 	struct acpi_table_events_work *tew;
2424 
2425 	tew = container_of(work, struct acpi_table_events_work, work);
2426 
2427 	if (tew->event == ACPI_TABLE_EVENT_LOAD) {
2428 		acpi_scan_lock_acquire();
2429 		acpi_bus_scan(ACPI_ROOT_OBJECT);
2430 		acpi_scan_lock_release();
2431 	}
2432 
2433 	kfree(tew);
2434 }
2435 
2436 void acpi_scan_table_handler(u32 event, void *table, void *context)
2437 {
2438 	struct acpi_table_events_work *tew;
2439 
2440 	if (!acpi_scan_initialized)
2441 		return;
2442 
2443 	if (event != ACPI_TABLE_EVENT_LOAD)
2444 		return;
2445 
2446 	tew = kmalloc(sizeof(*tew), GFP_KERNEL);
2447 	if (!tew)
2448 		return;
2449 
2450 	INIT_WORK(&tew->work, acpi_table_events_fn);
2451 	tew->table = table;
2452 	tew->event = event;
2453 
2454 	schedule_work(&tew->work);
2455 }
2456 
2457 int acpi_reconfig_notifier_register(struct notifier_block *nb)
2458 {
2459 	return blocking_notifier_chain_register(&acpi_reconfig_chain, nb);
2460 }
2461 EXPORT_SYMBOL(acpi_reconfig_notifier_register);
2462 
2463 int acpi_reconfig_notifier_unregister(struct notifier_block *nb)
2464 {
2465 	return blocking_notifier_chain_unregister(&acpi_reconfig_chain, nb);
2466 }
2467 EXPORT_SYMBOL(acpi_reconfig_notifier_unregister);
2468