xref: /linux/drivers/acpi/property.c (revision 58809f614e0e3f4e12b489bddf680bfeb31c0a20)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * ACPI device specific properties support.
4  *
5  * Copyright (C) 2014 - 2023, Intel Corporation
6  * All rights reserved.
7  *
8  * Authors: Mika Westerberg <mika.westerberg@linux.intel.com>
9  *          Darren Hart <dvhart@linux.intel.com>
10  *          Rafael J. Wysocki <rafael.j.wysocki@intel.com>
11  *          Sakari Ailus <sakari.ailus@linux.intel.com>
12  */
13 
14 #define pr_fmt(fmt) "ACPI: " fmt
15 
16 #include <linux/acpi.h>
17 #include <linux/device.h>
18 #include <linux/export.h>
19 
20 #include "internal.h"
21 
22 static int acpi_data_get_property_array(const struct acpi_device_data *data,
23 					const char *name,
24 					acpi_object_type type,
25 					const union acpi_object **obj);
26 
27 /*
28  * The GUIDs here are made equivalent to each other in order to avoid extra
29  * complexity in the properties handling code, with the caveat that the
30  * kernel will accept certain combinations of GUID and properties that are
31  * not defined without a warning. For instance if any of the properties
32  * from different GUID appear in a property list of another, it will be
33  * accepted by the kernel. Firmware validation tools should catch these.
34  *
35  * References:
36  *
37  * [1] UEFI DSD Guide.
38  *     https://github.com/UEFI/DSD-Guide/blob/main/src/dsd-guide.adoc
39  */
40 static const guid_t prp_guids[] = {
41 	/* ACPI _DSD device properties GUID [1]: daffd814-6eba-4d8c-8a91-bc9bbf4aa301 */
42 	GUID_INIT(0xdaffd814, 0x6eba, 0x4d8c,
43 		  0x8a, 0x91, 0xbc, 0x9b, 0xbf, 0x4a, 0xa3, 0x01),
44 	/* Hotplug in D3 GUID: 6211e2c0-58a3-4af3-90e1-927a4e0c55a4 */
45 	GUID_INIT(0x6211e2c0, 0x58a3, 0x4af3,
46 		  0x90, 0xe1, 0x92, 0x7a, 0x4e, 0x0c, 0x55, 0xa4),
47 	/* External facing port GUID: efcc06cc-73ac-4bc3-bff0-76143807c389 */
48 	GUID_INIT(0xefcc06cc, 0x73ac, 0x4bc3,
49 		  0xbf, 0xf0, 0x76, 0x14, 0x38, 0x07, 0xc3, 0x89),
50 	/* Thunderbolt GUID for IMR_VALID: c44d002f-69f9-4e7d-a904-a7baabdf43f7 */
51 	GUID_INIT(0xc44d002f, 0x69f9, 0x4e7d,
52 		  0xa9, 0x04, 0xa7, 0xba, 0xab, 0xdf, 0x43, 0xf7),
53 	/* Thunderbolt GUID for WAKE_SUPPORTED: 6c501103-c189-4296-ba72-9bf5a26ebe5d */
54 	GUID_INIT(0x6c501103, 0xc189, 0x4296,
55 		  0xba, 0x72, 0x9b, 0xf5, 0xa2, 0x6e, 0xbe, 0x5d),
56 	/* Storage device needs D3 GUID: 5025030f-842f-4ab4-a561-99a5189762d0 */
57 	GUID_INIT(0x5025030f, 0x842f, 0x4ab4,
58 		  0xa5, 0x61, 0x99, 0xa5, 0x18, 0x97, 0x62, 0xd0),
59 };
60 
61 /* ACPI _DSD data subnodes GUID [1]: dbb8e3e6-5886-4ba6-8795-1319f52a966b */
62 static const guid_t ads_guid =
63 	GUID_INIT(0xdbb8e3e6, 0x5886, 0x4ba6,
64 		  0x87, 0x95, 0x13, 0x19, 0xf5, 0x2a, 0x96, 0x6b);
65 
66 /* ACPI _DSD data buffer GUID [1]: edb12dd0-363d-4085-a3d2-49522ca160c4 */
67 static const guid_t buffer_prop_guid =
68 	GUID_INIT(0xedb12dd0, 0x363d, 0x4085,
69 		  0xa3, 0xd2, 0x49, 0x52, 0x2c, 0xa1, 0x60, 0xc4);
70 
71 static bool acpi_enumerate_nondev_subnodes(acpi_handle scope,
72 					   union acpi_object *desc,
73 					   struct acpi_device_data *data,
74 					   struct fwnode_handle *parent);
75 static bool acpi_extract_properties(acpi_handle handle,
76 				    union acpi_object *desc,
77 				    struct acpi_device_data *data);
78 
79 static bool acpi_nondev_subnode_extract(union acpi_object *desc,
80 					acpi_handle handle,
81 					const union acpi_object *link,
82 					struct list_head *list,
83 					struct fwnode_handle *parent)
84 {
85 	struct acpi_data_node *dn;
86 	acpi_handle scope = NULL;
87 	bool result;
88 
89 	if (acpi_graph_ignore_port(handle))
90 		return false;
91 
92 	dn = kzalloc(sizeof(*dn), GFP_KERNEL);
93 	if (!dn)
94 		return false;
95 
96 	dn->name = link->package.elements[0].string.pointer;
97 	fwnode_init(&dn->fwnode, &acpi_data_fwnode_ops);
98 	dn->parent = parent;
99 	INIT_LIST_HEAD(&dn->data.properties);
100 	INIT_LIST_HEAD(&dn->data.subnodes);
101 
102 	/*
103 	 * The scope for the completion of relative pathname segments and
104 	 * subnode object lookup is the one of the namespace node (device)
105 	 * containing the object that has returned the package.  That is, it's
106 	 * the scope of that object's parent device.
107 	 */
108 	if (handle)
109 		acpi_get_parent(handle, &scope);
110 
111 	/*
112 	 * Extract properties from the _DSD-equivalent package pointed to by
113 	 * desc and use scope (if not NULL) for the completion of relative
114 	 * pathname segments.
115 	 *
116 	 * The extracted properties will be held in the new data node dn.
117 	 */
118 	result = acpi_extract_properties(scope, desc, &dn->data);
119 	/*
120 	 * Look for subnodes in the _DSD-equivalent package pointed to by desc
121 	 * and create child nodes of dn if there are any.
122 	 */
123 	if (acpi_enumerate_nondev_subnodes(scope, desc, &dn->data, &dn->fwnode))
124 		result = true;
125 
126 	if (!result) {
127 		kfree(dn);
128 		acpi_handle_debug(handle, "Invalid properties/subnodes data, skipping\n");
129 		return false;
130 	}
131 
132 	/*
133 	 * This will be NULL if the desc package is embedded in an outer
134 	 * _DSD-equivalent package and its scope cannot be determined.
135 	 */
136 	dn->handle = handle;
137 	dn->data.pointer = desc;
138 	list_add_tail(&dn->sibling, list);
139 
140 	return true;
141 }
142 
143 static bool acpi_nondev_subnode_ok(acpi_handle scope,
144 				   const union acpi_object *link,
145 				   struct list_head *list,
146 				   struct fwnode_handle *parent)
147 {
148 	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
149 	acpi_handle handle;
150 	acpi_status status;
151 
152 	/*
153 	 * If the scope is unknown, the _DSD-equivalent package being parsed
154 	 * was embedded in an outer _DSD-equivalent package as a result of
155 	 * direct evaluation of an object pointed to by a reference.  In that
156 	 * case, using a pathname as the target object pointer is invalid.
157 	 */
158 	if (!scope)
159 		return false;
160 
161 	status = acpi_get_handle(scope, link->package.elements[1].string.pointer,
162 				 &handle);
163 	if (ACPI_FAILURE(status))
164 		return false;
165 
166 	status = acpi_evaluate_object_typed(handle, NULL, NULL, &buf,
167 					    ACPI_TYPE_PACKAGE);
168 	if (ACPI_FAILURE(status))
169 		return false;
170 
171 	if (acpi_nondev_subnode_extract(buf.pointer, handle, link, list,
172 					parent))
173 		return true;
174 
175 	ACPI_FREE(buf.pointer);
176 	return false;
177 }
178 
179 static bool acpi_add_nondev_subnodes(acpi_handle scope,
180 				     union acpi_object *links,
181 				     struct list_head *list,
182 				     struct fwnode_handle *parent)
183 {
184 	bool ret = false;
185 	int i;
186 
187 	/*
188 	 * Every element in the links package is expected to represent a link
189 	 * to a non-device node in a tree containing device-specific data.
190 	 */
191 	for (i = 0; i < links->package.count; i++) {
192 		union acpi_object *link, *desc;
193 		bool result;
194 
195 		link = &links->package.elements[i];
196 		/* Only two elements allowed. */
197 		if (link->package.count != 2)
198 			continue;
199 
200 		/* The first one (the key) must be a string. */
201 		if (link->package.elements[0].type != ACPI_TYPE_STRING)
202 			continue;
203 
204 		/* The second one (the target) may be a string or a package. */
205 		switch (link->package.elements[1].type) {
206 		case ACPI_TYPE_STRING:
207 			/*
208 			 * The string is expected to be a full pathname or a
209 			 * pathname segment relative to the given scope.  That
210 			 * pathname is expected to point to an object returning
211 			 * a package that contains _DSD-equivalent information.
212 			 */
213 			result = acpi_nondev_subnode_ok(scope, link, list,
214 							 parent);
215 			break;
216 		case ACPI_TYPE_PACKAGE:
217 			/*
218 			 * This happens when a reference is used in AML to
219 			 * point to the target.  Since the target is expected
220 			 * to be a named object, a reference to it will cause it
221 			 * to be avaluated in place and its return package will
222 			 * be embedded in the links package at the location of
223 			 * the reference.
224 			 *
225 			 * The target package is expected to contain _DSD-
226 			 * equivalent information, but the scope in which it
227 			 * is located in the original AML is unknown.  Thus
228 			 * it cannot contain pathname segments represented as
229 			 * strings because there is no way to build full
230 			 * pathnames out of them.
231 			 */
232 			acpi_handle_debug(scope, "subnode %s: Unknown scope\n",
233 					  link->package.elements[0].string.pointer);
234 			desc = &link->package.elements[1];
235 			result = acpi_nondev_subnode_extract(desc, NULL, link,
236 							     list, parent);
237 			break;
238 		case ACPI_TYPE_LOCAL_REFERENCE:
239 			/*
240 			 * It is not expected to see any local references in
241 			 * the links package because referencing a named object
242 			 * should cause it to be evaluated in place.
243 			 */
244 			acpi_handle_info(scope, "subnode %s: Unexpected reference\n",
245 					 link->package.elements[0].string.pointer);
246 			fallthrough;
247 		default:
248 			result = false;
249 			break;
250 		}
251 		ret = ret || result;
252 	}
253 
254 	return ret;
255 }
256 
257 static bool acpi_enumerate_nondev_subnodes(acpi_handle scope,
258 					   union acpi_object *desc,
259 					   struct acpi_device_data *data,
260 					   struct fwnode_handle *parent)
261 {
262 	int i;
263 
264 	/* Look for the ACPI data subnodes GUID. */
265 	for (i = 0; i < desc->package.count; i += 2) {
266 		const union acpi_object *guid;
267 		union acpi_object *links;
268 
269 		guid = &desc->package.elements[i];
270 		links = &desc->package.elements[i + 1];
271 
272 		/*
273 		 * The first element must be a GUID and the second one must be
274 		 * a package.
275 		 */
276 		if (guid->type != ACPI_TYPE_BUFFER ||
277 		    guid->buffer.length != 16 ||
278 		    links->type != ACPI_TYPE_PACKAGE)
279 			break;
280 
281 		if (!guid_equal((guid_t *)guid->buffer.pointer, &ads_guid))
282 			continue;
283 
284 		return acpi_add_nondev_subnodes(scope, links, &data->subnodes,
285 						parent);
286 	}
287 
288 	return false;
289 }
290 
291 static bool acpi_property_value_ok(const union acpi_object *value)
292 {
293 	int j;
294 
295 	/*
296 	 * The value must be an integer, a string, a reference, or a package
297 	 * whose every element must be an integer, a string, or a reference.
298 	 */
299 	switch (value->type) {
300 	case ACPI_TYPE_INTEGER:
301 	case ACPI_TYPE_STRING:
302 	case ACPI_TYPE_LOCAL_REFERENCE:
303 		return true;
304 
305 	case ACPI_TYPE_PACKAGE:
306 		for (j = 0; j < value->package.count; j++)
307 			switch (value->package.elements[j].type) {
308 			case ACPI_TYPE_INTEGER:
309 			case ACPI_TYPE_STRING:
310 			case ACPI_TYPE_LOCAL_REFERENCE:
311 				continue;
312 
313 			default:
314 				return false;
315 			}
316 
317 		return true;
318 	}
319 	return false;
320 }
321 
322 static bool acpi_properties_format_valid(const union acpi_object *properties)
323 {
324 	int i;
325 
326 	for (i = 0; i < properties->package.count; i++) {
327 		const union acpi_object *property;
328 
329 		property = &properties->package.elements[i];
330 		/*
331 		 * Only two elements allowed, the first one must be a string and
332 		 * the second one has to satisfy certain conditions.
333 		 */
334 		if (property->package.count != 2
335 		    || property->package.elements[0].type != ACPI_TYPE_STRING
336 		    || !acpi_property_value_ok(&property->package.elements[1]))
337 			return false;
338 	}
339 	return true;
340 }
341 
342 static void acpi_init_of_compatible(struct acpi_device *adev)
343 {
344 	const union acpi_object *of_compatible;
345 	int ret;
346 
347 	ret = acpi_data_get_property_array(&adev->data, "compatible",
348 					   ACPI_TYPE_STRING, &of_compatible);
349 	if (ret) {
350 		ret = acpi_dev_get_property(adev, "compatible",
351 					    ACPI_TYPE_STRING, &of_compatible);
352 		if (ret) {
353 			struct acpi_device *parent;
354 
355 			parent = acpi_dev_parent(adev);
356 			if (parent && parent->flags.of_compatible_ok)
357 				goto out;
358 
359 			return;
360 		}
361 	}
362 	adev->data.of_compatible = of_compatible;
363 
364  out:
365 	adev->flags.of_compatible_ok = 1;
366 }
367 
368 static bool acpi_is_property_guid(const guid_t *guid)
369 {
370 	int i;
371 
372 	for (i = 0; i < ARRAY_SIZE(prp_guids); i++) {
373 		if (guid_equal(guid, &prp_guids[i]))
374 			return true;
375 	}
376 
377 	return false;
378 }
379 
380 struct acpi_device_properties *
381 acpi_data_add_props(struct acpi_device_data *data, const guid_t *guid,
382 		    union acpi_object *properties)
383 {
384 	struct acpi_device_properties *props;
385 
386 	props = kzalloc(sizeof(*props), GFP_KERNEL);
387 	if (props) {
388 		INIT_LIST_HEAD(&props->list);
389 		props->guid = guid;
390 		props->properties = properties;
391 		list_add_tail(&props->list, &data->properties);
392 	}
393 
394 	return props;
395 }
396 
397 static void acpi_nondev_subnode_tag(acpi_handle handle, void *context)
398 {
399 }
400 
401 static void acpi_untie_nondev_subnodes(struct acpi_device_data *data)
402 {
403 	struct acpi_data_node *dn;
404 
405 	list_for_each_entry(dn, &data->subnodes, sibling) {
406 		if (!dn->handle)
407 			continue;
408 
409 		acpi_detach_data(dn->handle, acpi_nondev_subnode_tag);
410 
411 		acpi_untie_nondev_subnodes(&dn->data);
412 	}
413 }
414 
415 static bool acpi_tie_nondev_subnodes(struct acpi_device_data *data)
416 {
417 	struct acpi_data_node *dn;
418 
419 	list_for_each_entry(dn, &data->subnodes, sibling) {
420 		acpi_status status;
421 		bool ret;
422 
423 		if (!dn->handle)
424 			continue;
425 
426 		status = acpi_attach_data(dn->handle, acpi_nondev_subnode_tag, dn);
427 		if (ACPI_FAILURE(status) && status != AE_ALREADY_EXISTS) {
428 			acpi_handle_err(dn->handle, "Can't tag data node\n");
429 			return false;
430 		}
431 
432 		ret = acpi_tie_nondev_subnodes(&dn->data);
433 		if (!ret)
434 			return ret;
435 	}
436 
437 	return true;
438 }
439 
440 static void acpi_data_add_buffer_props(acpi_handle handle,
441 				       struct acpi_device_data *data,
442 				       union acpi_object *properties)
443 {
444 	struct acpi_device_properties *props;
445 	union acpi_object *package;
446 	size_t alloc_size;
447 	unsigned int i;
448 	u32 *count;
449 
450 	if (check_mul_overflow((size_t)properties->package.count,
451 			       sizeof(*package) + sizeof(void *),
452 			       &alloc_size) ||
453 	    check_add_overflow(sizeof(*props) + sizeof(*package), alloc_size,
454 			       &alloc_size)) {
455 		acpi_handle_warn(handle,
456 				 "can't allocate memory for %u buffer props",
457 				 properties->package.count);
458 		return;
459 	}
460 
461 	props = kvzalloc(alloc_size, GFP_KERNEL);
462 	if (!props)
463 		return;
464 
465 	props->guid = &buffer_prop_guid;
466 	props->bufs = (void *)(props + 1);
467 	props->properties = (void *)(props->bufs + properties->package.count);
468 
469 	/* Outer package */
470 	package = props->properties;
471 	package->type = ACPI_TYPE_PACKAGE;
472 	package->package.elements = package + 1;
473 	count = &package->package.count;
474 	*count = 0;
475 
476 	/* Inner packages */
477 	package++;
478 
479 	for (i = 0; i < properties->package.count; i++) {
480 		struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
481 		union acpi_object *property = &properties->package.elements[i];
482 		union acpi_object *prop, *obj, *buf_obj;
483 		acpi_status status;
484 
485 		if (property->type != ACPI_TYPE_PACKAGE ||
486 		    property->package.count != 2) {
487 			acpi_handle_warn(handle,
488 					 "buffer property %u has %u entries\n",
489 					 i, property->package.count);
490 			continue;
491 		}
492 
493 		prop = &property->package.elements[0];
494 		obj = &property->package.elements[1];
495 
496 		if (prop->type != ACPI_TYPE_STRING ||
497 		    obj->type != ACPI_TYPE_STRING) {
498 			acpi_handle_warn(handle,
499 					 "wrong object types %u and %u\n",
500 					 prop->type, obj->type);
501 			continue;
502 		}
503 
504 		status = acpi_evaluate_object_typed(handle, obj->string.pointer,
505 						    NULL, &buf,
506 						    ACPI_TYPE_BUFFER);
507 		if (ACPI_FAILURE(status)) {
508 			acpi_handle_warn(handle,
509 					 "can't evaluate \"%*pE\" as buffer\n",
510 					 obj->string.length,
511 					 obj->string.pointer);
512 			continue;
513 		}
514 
515 		package->type = ACPI_TYPE_PACKAGE;
516 		package->package.elements = prop;
517 		package->package.count = 2;
518 
519 		buf_obj = buf.pointer;
520 
521 		/* Replace the string object with a buffer object */
522 		obj->type = ACPI_TYPE_BUFFER;
523 		obj->buffer.length = buf_obj->buffer.length;
524 		obj->buffer.pointer = buf_obj->buffer.pointer;
525 
526 		props->bufs[i] = buf.pointer;
527 		package++;
528 		(*count)++;
529 	}
530 
531 	if (*count)
532 		list_add(&props->list, &data->properties);
533 	else
534 		kvfree(props);
535 }
536 
537 static bool acpi_extract_properties(acpi_handle scope, union acpi_object *desc,
538 				    struct acpi_device_data *data)
539 {
540 	int i;
541 
542 	if (desc->package.count % 2)
543 		return false;
544 
545 	/* Look for the device properties GUID. */
546 	for (i = 0; i < desc->package.count; i += 2) {
547 		const union acpi_object *guid;
548 		union acpi_object *properties;
549 
550 		guid = &desc->package.elements[i];
551 		properties = &desc->package.elements[i + 1];
552 
553 		/*
554 		 * The first element must be a GUID and the second one must be
555 		 * a package.
556 		 */
557 		if (guid->type != ACPI_TYPE_BUFFER ||
558 		    guid->buffer.length != 16 ||
559 		    properties->type != ACPI_TYPE_PACKAGE)
560 			break;
561 
562 		if (guid_equal((guid_t *)guid->buffer.pointer,
563 			       &buffer_prop_guid)) {
564 			acpi_data_add_buffer_props(scope, data, properties);
565 			continue;
566 		}
567 
568 		if (!acpi_is_property_guid((guid_t *)guid->buffer.pointer))
569 			continue;
570 
571 		/*
572 		 * We found the matching GUID. Now validate the format of the
573 		 * package immediately following it.
574 		 */
575 		if (!acpi_properties_format_valid(properties))
576 			continue;
577 
578 		acpi_data_add_props(data, (const guid_t *)guid->buffer.pointer,
579 				    properties);
580 	}
581 
582 	return !list_empty(&data->properties);
583 }
584 
585 void acpi_init_properties(struct acpi_device *adev)
586 {
587 	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
588 	struct acpi_hardware_id *hwid;
589 	acpi_status status;
590 	bool acpi_of = false;
591 
592 	INIT_LIST_HEAD(&adev->data.properties);
593 	INIT_LIST_HEAD(&adev->data.subnodes);
594 
595 	if (!adev->handle)
596 		return;
597 
598 	/*
599 	 * Check if ACPI_DT_NAMESPACE_HID is present and inthat case we fill in
600 	 * Device Tree compatible properties for this device.
601 	 */
602 	list_for_each_entry(hwid, &adev->pnp.ids, list) {
603 		if (!strcmp(hwid->id, ACPI_DT_NAMESPACE_HID)) {
604 			acpi_of = true;
605 			break;
606 		}
607 	}
608 
609 	status = acpi_evaluate_object_typed(adev->handle, "_DSD", NULL, &buf,
610 					    ACPI_TYPE_PACKAGE);
611 	if (ACPI_FAILURE(status))
612 		goto out;
613 
614 	if (acpi_extract_properties(adev->handle, buf.pointer, &adev->data)) {
615 		adev->data.pointer = buf.pointer;
616 		if (acpi_of)
617 			acpi_init_of_compatible(adev);
618 	}
619 	if (acpi_enumerate_nondev_subnodes(adev->handle, buf.pointer,
620 					&adev->data, acpi_fwnode_handle(adev)))
621 		adev->data.pointer = buf.pointer;
622 
623 	if (!adev->data.pointer) {
624 		acpi_handle_debug(adev->handle, "Invalid _DSD data, skipping\n");
625 		ACPI_FREE(buf.pointer);
626 	} else {
627 		if (!acpi_tie_nondev_subnodes(&adev->data))
628 			acpi_untie_nondev_subnodes(&adev->data);
629 	}
630 
631  out:
632 	if (acpi_of && !adev->flags.of_compatible_ok)
633 		acpi_handle_info(adev->handle,
634 			 ACPI_DT_NAMESPACE_HID " requires 'compatible' property\n");
635 
636 	if (!adev->data.pointer)
637 		acpi_extract_apple_properties(adev);
638 }
639 
640 static void acpi_free_device_properties(struct list_head *list)
641 {
642 	struct acpi_device_properties *props, *tmp;
643 
644 	list_for_each_entry_safe(props, tmp, list, list) {
645 		u32 i;
646 
647 		list_del(&props->list);
648 		/* Buffer data properties were separately allocated */
649 		if (props->bufs)
650 			for (i = 0; i < props->properties->package.count; i++)
651 				ACPI_FREE(props->bufs[i]);
652 		kvfree(props);
653 	}
654 }
655 
656 static void acpi_destroy_nondev_subnodes(struct list_head *list)
657 {
658 	struct acpi_data_node *dn, *next;
659 
660 	if (list_empty(list))
661 		return;
662 
663 	list_for_each_entry_safe_reverse(dn, next, list, sibling) {
664 		acpi_destroy_nondev_subnodes(&dn->data.subnodes);
665 		wait_for_completion(&dn->kobj_done);
666 		list_del(&dn->sibling);
667 		ACPI_FREE((void *)dn->data.pointer);
668 		acpi_free_device_properties(&dn->data.properties);
669 		kfree(dn);
670 	}
671 }
672 
673 void acpi_free_properties(struct acpi_device *adev)
674 {
675 	acpi_untie_nondev_subnodes(&adev->data);
676 	acpi_destroy_nondev_subnodes(&adev->data.subnodes);
677 	ACPI_FREE((void *)adev->data.pointer);
678 	adev->data.of_compatible = NULL;
679 	adev->data.pointer = NULL;
680 	acpi_free_device_properties(&adev->data.properties);
681 }
682 
683 /**
684  * acpi_data_get_property - return an ACPI property with given name
685  * @data: ACPI device deta object to get the property from
686  * @name: Name of the property
687  * @type: Expected property type
688  * @obj: Location to store the property value (if not %NULL)
689  *
690  * Look up a property with @name and store a pointer to the resulting ACPI
691  * object at the location pointed to by @obj if found.
692  *
693  * Callers must not attempt to free the returned objects.  These objects will be
694  * freed by the ACPI core automatically during the removal of @data.
695  *
696  * Return: %0 if property with @name has been found (success),
697  *         %-EINVAL if the arguments are invalid,
698  *         %-EINVAL if the property doesn't exist,
699  *         %-EPROTO if the property value type doesn't match @type.
700  */
701 static int acpi_data_get_property(const struct acpi_device_data *data,
702 				  const char *name, acpi_object_type type,
703 				  const union acpi_object **obj)
704 {
705 	const struct acpi_device_properties *props;
706 
707 	if (!data || !name)
708 		return -EINVAL;
709 
710 	if (!data->pointer || list_empty(&data->properties))
711 		return -EINVAL;
712 
713 	list_for_each_entry(props, &data->properties, list) {
714 		const union acpi_object *properties;
715 		unsigned int i;
716 
717 		properties = props->properties;
718 		for (i = 0; i < properties->package.count; i++) {
719 			const union acpi_object *propname, *propvalue;
720 			const union acpi_object *property;
721 
722 			property = &properties->package.elements[i];
723 
724 			propname = &property->package.elements[0];
725 			propvalue = &property->package.elements[1];
726 
727 			if (!strcmp(name, propname->string.pointer)) {
728 				if (type != ACPI_TYPE_ANY &&
729 				    propvalue->type != type)
730 					return -EPROTO;
731 				if (obj)
732 					*obj = propvalue;
733 
734 				return 0;
735 			}
736 		}
737 	}
738 	return -EINVAL;
739 }
740 
741 /**
742  * acpi_dev_get_property - return an ACPI property with given name.
743  * @adev: ACPI device to get the property from.
744  * @name: Name of the property.
745  * @type: Expected property type.
746  * @obj: Location to store the property value (if not %NULL).
747  */
748 int acpi_dev_get_property(const struct acpi_device *adev, const char *name,
749 			  acpi_object_type type, const union acpi_object **obj)
750 {
751 	return adev ? acpi_data_get_property(&adev->data, name, type, obj) : -EINVAL;
752 }
753 EXPORT_SYMBOL_GPL(acpi_dev_get_property);
754 
755 static const struct acpi_device_data *
756 acpi_device_data_of_node(const struct fwnode_handle *fwnode)
757 {
758 	if (is_acpi_device_node(fwnode)) {
759 		const struct acpi_device *adev = to_acpi_device_node(fwnode);
760 		return &adev->data;
761 	}
762 	if (is_acpi_data_node(fwnode)) {
763 		const struct acpi_data_node *dn = to_acpi_data_node(fwnode);
764 		return &dn->data;
765 	}
766 	return NULL;
767 }
768 
769 /**
770  * acpi_node_prop_get - return an ACPI property with given name.
771  * @fwnode: Firmware node to get the property from.
772  * @propname: Name of the property.
773  * @valptr: Location to store a pointer to the property value (if not %NULL).
774  */
775 int acpi_node_prop_get(const struct fwnode_handle *fwnode,
776 		       const char *propname, void **valptr)
777 {
778 	return acpi_data_get_property(acpi_device_data_of_node(fwnode),
779 				      propname, ACPI_TYPE_ANY,
780 				      (const union acpi_object **)valptr);
781 }
782 
783 /**
784  * acpi_data_get_property_array - return an ACPI array property with given name
785  * @data: ACPI data object to get the property from
786  * @name: Name of the property
787  * @type: Expected type of array elements
788  * @obj: Location to store a pointer to the property value (if not NULL)
789  *
790  * Look up an array property with @name and store a pointer to the resulting
791  * ACPI object at the location pointed to by @obj if found.
792  *
793  * Callers must not attempt to free the returned objects.  Those objects will be
794  * freed by the ACPI core automatically during the removal of @data.
795  *
796  * Return: %0 if array property (package) with @name has been found (success),
797  *         %-EINVAL if the arguments are invalid,
798  *         %-EINVAL if the property doesn't exist,
799  *         %-EPROTO if the property is not a package or the type of its elements
800  *           doesn't match @type.
801  */
802 static int acpi_data_get_property_array(const struct acpi_device_data *data,
803 					const char *name,
804 					acpi_object_type type,
805 					const union acpi_object **obj)
806 {
807 	const union acpi_object *prop;
808 	int ret, i;
809 
810 	ret = acpi_data_get_property(data, name, ACPI_TYPE_PACKAGE, &prop);
811 	if (ret)
812 		return ret;
813 
814 	if (type != ACPI_TYPE_ANY) {
815 		/* Check that all elements are of correct type. */
816 		for (i = 0; i < prop->package.count; i++)
817 			if (prop->package.elements[i].type != type)
818 				return -EPROTO;
819 	}
820 	if (obj)
821 		*obj = prop;
822 
823 	return 0;
824 }
825 
826 static struct fwnode_handle *
827 acpi_fwnode_get_named_child_node(const struct fwnode_handle *fwnode,
828 				 const char *childname)
829 {
830 	struct fwnode_handle *child;
831 
832 	fwnode_for_each_child_node(fwnode, child) {
833 		if (is_acpi_data_node(child)) {
834 			if (acpi_data_node_match(child, childname))
835 				return child;
836 			continue;
837 		}
838 
839 		if (!strncmp(acpi_device_bid(to_acpi_device_node(child)),
840 			     childname, ACPI_NAMESEG_SIZE))
841 			return child;
842 	}
843 
844 	return NULL;
845 }
846 
847 static int acpi_get_ref_args(struct fwnode_reference_args *args,
848 			     struct fwnode_handle *ref_fwnode,
849 			     const union acpi_object **element,
850 			     const union acpi_object *end, size_t num_args)
851 {
852 	u32 nargs = 0, i;
853 
854 	/*
855 	 * Assume the following integer elements are all args. Stop counting on
856 	 * the first reference (possibly represented as a string) or end of the
857 	 * package arguments. In case of neither reference, nor integer, return
858 	 * an error, we can't parse it.
859 	 */
860 	for (i = 0; (*element) + i < end && i < num_args; i++) {
861 		acpi_object_type type = (*element)[i].type;
862 
863 		if (type == ACPI_TYPE_LOCAL_REFERENCE || type == ACPI_TYPE_STRING)
864 			break;
865 
866 		if (type == ACPI_TYPE_INTEGER)
867 			nargs++;
868 		else
869 			return -EINVAL;
870 	}
871 
872 	if (nargs > NR_FWNODE_REFERENCE_ARGS)
873 		return -EINVAL;
874 
875 	if (args) {
876 		args->fwnode = ref_fwnode;
877 		args->nargs = nargs;
878 		for (i = 0; i < nargs; i++)
879 			args->args[i] = (*element)[i].integer.value;
880 	}
881 
882 	(*element) += nargs;
883 
884 	return 0;
885 }
886 
887 static struct fwnode_handle *acpi_parse_string_ref(const struct fwnode_handle *fwnode,
888 						   const char *refstring)
889 {
890 	acpi_handle scope, handle;
891 	struct acpi_data_node *dn;
892 	struct acpi_device *device;
893 	acpi_status status;
894 
895 	if (is_acpi_device_node(fwnode)) {
896 		scope = to_acpi_device_node(fwnode)->handle;
897 	} else if (is_acpi_data_node(fwnode)) {
898 		scope = to_acpi_data_node(fwnode)->handle;
899 	} else {
900 		pr_debug("Bad node type for node %pfw\n", fwnode);
901 		return NULL;
902 	}
903 
904 	status = acpi_get_handle(scope, refstring, &handle);
905 	if (ACPI_FAILURE(status)) {
906 		acpi_handle_debug(scope, "Unable to get an ACPI handle for %s\n",
907 				  refstring);
908 		return NULL;
909 	}
910 
911 	device = acpi_fetch_acpi_dev(handle);
912 	if (device)
913 		return acpi_fwnode_handle(device);
914 
915 	status = acpi_get_data_full(handle, acpi_nondev_subnode_tag,
916 				    (void **)&dn, NULL);
917 	if (ACPI_FAILURE(status) || !dn) {
918 		acpi_handle_debug(handle, "Subnode not found\n");
919 		return NULL;
920 	}
921 
922 	return &dn->fwnode;
923 }
924 
925 /**
926  * __acpi_node_get_property_reference - returns handle to the referenced object
927  * @fwnode: Firmware node to get the property from
928  * @propname: Name of the property
929  * @index: Index of the reference to return
930  * @num_args: Maximum number of arguments after each reference
931  * @args: Location to store the returned reference with optional arguments
932  *	  (may be NULL)
933  *
934  * Find property with @name, verifify that it is a package containing at least
935  * one object reference and if so, store the ACPI device object pointer to the
936  * target object in @args->adev.  If the reference includes arguments, store
937  * them in the @args->args[] array.
938  *
939  * If there's more than one reference in the property value package, @index is
940  * used to select the one to return.
941  *
942  * It is possible to leave holes in the property value set like in the
943  * example below:
944  *
945  * Package () {
946  *     "cs-gpios",
947  *     Package () {
948  *        ^GPIO, 19, 0, 0,
949  *        ^GPIO, 20, 0, 0,
950  *        0,
951  *        ^GPIO, 21, 0, 0,
952  *     }
953  * }
954  *
955  * Calling this function with index %2 or index %3 return %-ENOENT. If the
956  * property does not contain any more values %-ENOENT is returned. The NULL
957  * entry must be single integer and preferably contain value %0.
958  *
959  * Return: %0 on success, negative error code on failure.
960  */
961 int __acpi_node_get_property_reference(const struct fwnode_handle *fwnode,
962 	const char *propname, size_t index, size_t num_args,
963 	struct fwnode_reference_args *args)
964 {
965 	const union acpi_object *element, *end;
966 	const union acpi_object *obj;
967 	const struct acpi_device_data *data;
968 	struct fwnode_handle *ref_fwnode;
969 	struct acpi_device *device;
970 	int ret, idx = 0;
971 
972 	data = acpi_device_data_of_node(fwnode);
973 	if (!data)
974 		return -ENOENT;
975 
976 	ret = acpi_data_get_property(data, propname, ACPI_TYPE_ANY, &obj);
977 	if (ret)
978 		return ret == -EINVAL ? -ENOENT : -EINVAL;
979 
980 	switch (obj->type) {
981 	case ACPI_TYPE_LOCAL_REFERENCE:
982 		/* Plain single reference without arguments. */
983 		if (index)
984 			return -ENOENT;
985 
986 		device = acpi_fetch_acpi_dev(obj->reference.handle);
987 		if (!device)
988 			return -EINVAL;
989 
990 		if (!args)
991 			return 0;
992 
993 		args->fwnode = acpi_fwnode_handle(device);
994 		args->nargs = 0;
995 
996 		return 0;
997 	case ACPI_TYPE_STRING:
998 		if (index)
999 			return -ENOENT;
1000 
1001 		ref_fwnode = acpi_parse_string_ref(fwnode, obj->string.pointer);
1002 		if (!ref_fwnode)
1003 			return -EINVAL;
1004 
1005 		args->fwnode = ref_fwnode;
1006 		args->nargs = 0;
1007 
1008 		return 0;
1009 	case ACPI_TYPE_PACKAGE:
1010 		/*
1011 		 * If it is not a single reference, then it is a package of
1012 		 * references, followed by number of ints as follows:
1013 		 *
1014 		 *  Package () { REF, INT, REF, INT, INT }
1015 		 *
1016 		 * Here, REF may be either a local reference or a string. The
1017 		 * index argument is then used to determine which reference the
1018 		 * caller wants (along with the arguments).
1019 		 */
1020 		break;
1021 	default:
1022 		return -EINVAL;
1023 	}
1024 
1025 	if (index >= obj->package.count)
1026 		return -ENOENT;
1027 
1028 	element = obj->package.elements;
1029 	end = element + obj->package.count;
1030 
1031 	while (element < end) {
1032 		switch (element->type) {
1033 		case ACPI_TYPE_LOCAL_REFERENCE:
1034 			device = acpi_fetch_acpi_dev(element->reference.handle);
1035 			if (!device)
1036 				return -EINVAL;
1037 
1038 			element++;
1039 
1040 			ret = acpi_get_ref_args(idx == index ? args : NULL,
1041 						acpi_fwnode_handle(device),
1042 						&element, end, num_args);
1043 			if (ret < 0)
1044 				return ret;
1045 
1046 			if (idx == index)
1047 				return 0;
1048 
1049 			break;
1050 		case ACPI_TYPE_STRING:
1051 			ref_fwnode = acpi_parse_string_ref(fwnode,
1052 							   element->string.pointer);
1053 			if (!ref_fwnode)
1054 				return -EINVAL;
1055 
1056 			element++;
1057 
1058 			ret = acpi_get_ref_args(idx == index ? args : NULL,
1059 						ref_fwnode, &element, end,
1060 						num_args);
1061 			if (ret < 0)
1062 				return ret;
1063 
1064 			if (idx == index)
1065 				return 0;
1066 
1067 			break;
1068 		case ACPI_TYPE_INTEGER:
1069 			if (idx == index)
1070 				return -ENOENT;
1071 			element++;
1072 			break;
1073 		default:
1074 			return -EINVAL;
1075 		}
1076 
1077 		idx++;
1078 	}
1079 
1080 	return -ENOENT;
1081 }
1082 EXPORT_SYMBOL_GPL(__acpi_node_get_property_reference);
1083 
1084 static int acpi_data_prop_read_single(const struct acpi_device_data *data,
1085 				      const char *propname,
1086 				      enum dev_prop_type proptype, void *val)
1087 {
1088 	const union acpi_object *obj;
1089 	int ret = 0;
1090 
1091 	if (proptype >= DEV_PROP_U8 && proptype <= DEV_PROP_U64)
1092 		ret = acpi_data_get_property(data, propname, ACPI_TYPE_INTEGER, &obj);
1093 	else if (proptype == DEV_PROP_STRING)
1094 		ret = acpi_data_get_property(data, propname, ACPI_TYPE_STRING, &obj);
1095 	if (ret)
1096 		return ret;
1097 
1098 	switch (proptype) {
1099 	case DEV_PROP_U8:
1100 		if (obj->integer.value > U8_MAX)
1101 			return -EOVERFLOW;
1102 		if (val)
1103 			*(u8 *)val = obj->integer.value;
1104 		break;
1105 	case DEV_PROP_U16:
1106 		if (obj->integer.value > U16_MAX)
1107 			return -EOVERFLOW;
1108 		if (val)
1109 			*(u16 *)val = obj->integer.value;
1110 		break;
1111 	case DEV_PROP_U32:
1112 		if (obj->integer.value > U32_MAX)
1113 			return -EOVERFLOW;
1114 		if (val)
1115 			*(u32 *)val = obj->integer.value;
1116 		break;
1117 	case DEV_PROP_U64:
1118 		if (val)
1119 			*(u64 *)val = obj->integer.value;
1120 		break;
1121 	case DEV_PROP_STRING:
1122 		if (val)
1123 			*(char **)val = obj->string.pointer;
1124 		return 1;
1125 	default:
1126 		return -EINVAL;
1127 	}
1128 
1129 	/* When no storage provided return number of available values */
1130 	return val ? 0 : 1;
1131 }
1132 
1133 #define acpi_copy_property_array_uint(items, val, nval)			\
1134 	({								\
1135 		typeof(items) __items = items;				\
1136 		typeof(val) __val = val;				\
1137 		typeof(nval) __nval = nval;				\
1138 		size_t i;						\
1139 		int ret = 0;						\
1140 									\
1141 		for (i = 0; i < __nval; i++) {				\
1142 			if (__items->type == ACPI_TYPE_BUFFER) {	\
1143 				__val[i] = __items->buffer.pointer[i];	\
1144 				continue;				\
1145 			}						\
1146 			if (__items[i].type != ACPI_TYPE_INTEGER) {	\
1147 				ret = -EPROTO;				\
1148 				break;					\
1149 			}						\
1150 			if (__items[i].integer.value > _Generic(__val,	\
1151 								u8 *: U8_MAX, \
1152 								u16 *: U16_MAX, \
1153 								u32 *: U32_MAX, \
1154 								u64 *: U64_MAX)) { \
1155 				ret = -EOVERFLOW;			\
1156 				break;					\
1157 			}						\
1158 									\
1159 			__val[i] = __items[i].integer.value;		\
1160 		}							\
1161 		ret;							\
1162 	})
1163 
1164 static int acpi_copy_property_array_string(const union acpi_object *items,
1165 					   char **val, size_t nval)
1166 {
1167 	int i;
1168 
1169 	for (i = 0; i < nval; i++) {
1170 		if (items[i].type != ACPI_TYPE_STRING)
1171 			return -EPROTO;
1172 
1173 		val[i] = items[i].string.pointer;
1174 	}
1175 	return nval;
1176 }
1177 
1178 static int acpi_data_prop_read(const struct acpi_device_data *data,
1179 			       const char *propname,
1180 			       enum dev_prop_type proptype,
1181 			       void *val, size_t nval)
1182 {
1183 	const union acpi_object *obj;
1184 	const union acpi_object *items;
1185 	int ret;
1186 
1187 	if (nval == 1 || !val) {
1188 		ret = acpi_data_prop_read_single(data, propname, proptype, val);
1189 		/*
1190 		 * The overflow error means that the property is there and it is
1191 		 * single-value, but its type does not match, so return.
1192 		 */
1193 		if (ret >= 0 || ret == -EOVERFLOW)
1194 			return ret;
1195 
1196 		/*
1197 		 * Reading this property as a single-value one failed, but its
1198 		 * value may still be represented as one-element array, so
1199 		 * continue.
1200 		 */
1201 	}
1202 
1203 	ret = acpi_data_get_property_array(data, propname, ACPI_TYPE_ANY, &obj);
1204 	if (ret && proptype >= DEV_PROP_U8 && proptype <= DEV_PROP_U64)
1205 		ret = acpi_data_get_property(data, propname, ACPI_TYPE_BUFFER,
1206 					     &obj);
1207 	if (ret)
1208 		return ret;
1209 
1210 	if (!val) {
1211 		if (obj->type == ACPI_TYPE_BUFFER)
1212 			return obj->buffer.length;
1213 
1214 		return obj->package.count;
1215 	}
1216 
1217 	switch (proptype) {
1218 	case DEV_PROP_STRING:
1219 		break;
1220 	default:
1221 		if (obj->type == ACPI_TYPE_BUFFER) {
1222 			if (nval > obj->buffer.length)
1223 				return -EOVERFLOW;
1224 		} else {
1225 			if (nval > obj->package.count)
1226 				return -EOVERFLOW;
1227 		}
1228 		break;
1229 	}
1230 
1231 	if (obj->type == ACPI_TYPE_BUFFER) {
1232 		if (proptype != DEV_PROP_U8)
1233 			return -EPROTO;
1234 		items = obj;
1235 	} else {
1236 		items = obj->package.elements;
1237 	}
1238 
1239 	switch (proptype) {
1240 	case DEV_PROP_U8:
1241 		ret = acpi_copy_property_array_uint(items, (u8 *)val, nval);
1242 		break;
1243 	case DEV_PROP_U16:
1244 		ret = acpi_copy_property_array_uint(items, (u16 *)val, nval);
1245 		break;
1246 	case DEV_PROP_U32:
1247 		ret = acpi_copy_property_array_uint(items, (u32 *)val, nval);
1248 		break;
1249 	case DEV_PROP_U64:
1250 		ret = acpi_copy_property_array_uint(items, (u64 *)val, nval);
1251 		break;
1252 	case DEV_PROP_STRING:
1253 		nval = min_t(u32, nval, obj->package.count);
1254 		if (nval == 0)
1255 			return -ENODATA;
1256 
1257 		ret = acpi_copy_property_array_string(items, (char **)val, nval);
1258 		break;
1259 	default:
1260 		ret = -EINVAL;
1261 		break;
1262 	}
1263 	return ret;
1264 }
1265 
1266 /**
1267  * acpi_node_prop_read - retrieve the value of an ACPI property with given name.
1268  * @fwnode: Firmware node to get the property from.
1269  * @propname: Name of the property.
1270  * @proptype: Expected property type.
1271  * @val: Location to store the property value (if not %NULL).
1272  * @nval: Size of the array pointed to by @val.
1273  *
1274  * If @val is %NULL, return the number of array elements comprising the value
1275  * of the property.  Otherwise, read at most @nval values to the array at the
1276  * location pointed to by @val.
1277  */
1278 static int acpi_node_prop_read(const struct fwnode_handle *fwnode,
1279 			       const char *propname, enum dev_prop_type proptype,
1280 			       void *val, size_t nval)
1281 {
1282 	return acpi_data_prop_read(acpi_device_data_of_node(fwnode),
1283 				   propname, proptype, val, nval);
1284 }
1285 
1286 static int stop_on_next(struct acpi_device *adev, void *data)
1287 {
1288 	struct acpi_device **ret_p = data;
1289 
1290 	if (!*ret_p) {
1291 		*ret_p = adev;
1292 		return 1;
1293 	}
1294 
1295 	/* Skip until the "previous" object is found. */
1296 	if (*ret_p == adev)
1297 		*ret_p = NULL;
1298 
1299 	return 0;
1300 }
1301 
1302 /**
1303  * acpi_get_next_subnode - Return the next child node handle for a fwnode
1304  * @fwnode: Firmware node to find the next child node for.
1305  * @child: Handle to one of the device's child nodes or a null handle.
1306  */
1307 struct fwnode_handle *acpi_get_next_subnode(const struct fwnode_handle *fwnode,
1308 					    struct fwnode_handle *child)
1309 {
1310 	struct acpi_device *adev = to_acpi_device_node(fwnode);
1311 
1312 	if ((!child || is_acpi_device_node(child)) && adev) {
1313 		struct acpi_device *child_adev = to_acpi_device_node(child);
1314 
1315 		acpi_dev_for_each_child(adev, stop_on_next, &child_adev);
1316 		if (child_adev)
1317 			return acpi_fwnode_handle(child_adev);
1318 
1319 		child = NULL;
1320 	}
1321 
1322 	if (!child || is_acpi_data_node(child)) {
1323 		const struct acpi_data_node *data = to_acpi_data_node(fwnode);
1324 		const struct list_head *head;
1325 		struct list_head *next;
1326 		struct acpi_data_node *dn;
1327 
1328 		/*
1329 		 * We can have a combination of device and data nodes, e.g. with
1330 		 * hierarchical _DSD properties. Make sure the adev pointer is
1331 		 * restored before going through data nodes, otherwise we will
1332 		 * be looking for data_nodes below the last device found instead
1333 		 * of the common fwnode shared by device_nodes and data_nodes.
1334 		 */
1335 		adev = to_acpi_device_node(fwnode);
1336 		if (adev)
1337 			head = &adev->data.subnodes;
1338 		else if (data)
1339 			head = &data->data.subnodes;
1340 		else
1341 			return NULL;
1342 
1343 		if (list_empty(head))
1344 			return NULL;
1345 
1346 		if (child) {
1347 			dn = to_acpi_data_node(child);
1348 			next = dn->sibling.next;
1349 			if (next == head)
1350 				return NULL;
1351 
1352 			dn = list_entry(next, struct acpi_data_node, sibling);
1353 		} else {
1354 			dn = list_first_entry(head, struct acpi_data_node, sibling);
1355 		}
1356 		return &dn->fwnode;
1357 	}
1358 	return NULL;
1359 }
1360 
1361 /**
1362  * acpi_node_get_parent - Return parent fwnode of this fwnode
1363  * @fwnode: Firmware node whose parent to get
1364  *
1365  * Returns parent node of an ACPI device or data firmware node or %NULL if
1366  * not available.
1367  */
1368 static struct fwnode_handle *
1369 acpi_node_get_parent(const struct fwnode_handle *fwnode)
1370 {
1371 	if (is_acpi_data_node(fwnode)) {
1372 		/* All data nodes have parent pointer so just return that */
1373 		return to_acpi_data_node(fwnode)->parent;
1374 	}
1375 	if (is_acpi_device_node(fwnode)) {
1376 		struct acpi_device *parent;
1377 
1378 		parent = acpi_dev_parent(to_acpi_device_node(fwnode));
1379 		if (parent)
1380 			return acpi_fwnode_handle(parent);
1381 	}
1382 
1383 	return NULL;
1384 }
1385 
1386 /*
1387  * Return true if the node is an ACPI graph node. Called on either ports
1388  * or endpoints.
1389  */
1390 static bool is_acpi_graph_node(struct fwnode_handle *fwnode,
1391 			       const char *str)
1392 {
1393 	unsigned int len = strlen(str);
1394 	const char *name;
1395 
1396 	if (!len || !is_acpi_data_node(fwnode))
1397 		return false;
1398 
1399 	name = to_acpi_data_node(fwnode)->name;
1400 
1401 	return (fwnode_property_present(fwnode, "reg") &&
1402 		!strncmp(name, str, len) && name[len] == '@') ||
1403 		fwnode_property_present(fwnode, str);
1404 }
1405 
1406 /**
1407  * acpi_graph_get_next_endpoint - Get next endpoint ACPI firmware node
1408  * @fwnode: Pointer to the parent firmware node
1409  * @prev: Previous endpoint node or %NULL to get the first
1410  *
1411  * Looks up next endpoint ACPI firmware node below a given @fwnode. Returns
1412  * %NULL if there is no next endpoint or in case of error. In case of success
1413  * the next endpoint is returned.
1414  */
1415 static struct fwnode_handle *acpi_graph_get_next_endpoint(
1416 	const struct fwnode_handle *fwnode, struct fwnode_handle *prev)
1417 {
1418 	struct fwnode_handle *port = NULL;
1419 	struct fwnode_handle *endpoint;
1420 
1421 	if (!prev) {
1422 		do {
1423 			port = fwnode_get_next_child_node(fwnode, port);
1424 			/*
1425 			 * The names of the port nodes begin with "port@"
1426 			 * followed by the number of the port node and they also
1427 			 * have a "reg" property that also has the number of the
1428 			 * port node. For compatibility reasons a node is also
1429 			 * recognised as a port node from the "port" property.
1430 			 */
1431 			if (is_acpi_graph_node(port, "port"))
1432 				break;
1433 		} while (port);
1434 	} else {
1435 		port = fwnode_get_parent(prev);
1436 	}
1437 
1438 	if (!port)
1439 		return NULL;
1440 
1441 	endpoint = fwnode_get_next_child_node(port, prev);
1442 	while (!endpoint) {
1443 		port = fwnode_get_next_child_node(fwnode, port);
1444 		if (!port)
1445 			break;
1446 		if (is_acpi_graph_node(port, "port"))
1447 			endpoint = fwnode_get_next_child_node(port, NULL);
1448 	}
1449 
1450 	/*
1451 	 * The names of the endpoint nodes begin with "endpoint@" followed by
1452 	 * the number of the endpoint node and they also have a "reg" property
1453 	 * that also has the number of the endpoint node. For compatibility
1454 	 * reasons a node is also recognised as an endpoint node from the
1455 	 * "endpoint" property.
1456 	 */
1457 	if (!is_acpi_graph_node(endpoint, "endpoint"))
1458 		return NULL;
1459 
1460 	return endpoint;
1461 }
1462 
1463 /**
1464  * acpi_graph_get_child_prop_value - Return a child with a given property value
1465  * @fwnode: device fwnode
1466  * @prop_name: The name of the property to look for
1467  * @val: the desired property value
1468  *
1469  * Return the port node corresponding to a given port number. Returns
1470  * the child node on success, NULL otherwise.
1471  */
1472 static struct fwnode_handle *acpi_graph_get_child_prop_value(
1473 	const struct fwnode_handle *fwnode, const char *prop_name,
1474 	unsigned int val)
1475 {
1476 	struct fwnode_handle *child;
1477 
1478 	fwnode_for_each_child_node(fwnode, child) {
1479 		u32 nr;
1480 
1481 		if (fwnode_property_read_u32(child, prop_name, &nr))
1482 			continue;
1483 
1484 		if (val == nr)
1485 			return child;
1486 	}
1487 
1488 	return NULL;
1489 }
1490 
1491 
1492 /**
1493  * acpi_graph_get_remote_endpoint - Parses and returns remote end of an endpoint
1494  * @__fwnode: Endpoint firmware node pointing to a remote device
1495  *
1496  * Returns the remote endpoint corresponding to @__fwnode. NULL on error.
1497  */
1498 static struct fwnode_handle *
1499 acpi_graph_get_remote_endpoint(const struct fwnode_handle *__fwnode)
1500 {
1501 	struct fwnode_handle *fwnode;
1502 	unsigned int port_nr, endpoint_nr;
1503 	struct fwnode_reference_args args;
1504 	int ret;
1505 
1506 	memset(&args, 0, sizeof(args));
1507 	ret = acpi_node_get_property_reference(__fwnode, "remote-endpoint", 0,
1508 					       &args);
1509 	if (ret)
1510 		return NULL;
1511 
1512 	/* Direct endpoint reference? */
1513 	if (!is_acpi_device_node(args.fwnode))
1514 		return args.nargs ? NULL : args.fwnode;
1515 
1516 	/*
1517 	 * Always require two arguments with the reference: port and
1518 	 * endpoint indices.
1519 	 */
1520 	if (args.nargs != 2)
1521 		return NULL;
1522 
1523 	fwnode = args.fwnode;
1524 	port_nr = args.args[0];
1525 	endpoint_nr = args.args[1];
1526 
1527 	fwnode = acpi_graph_get_child_prop_value(fwnode, "port", port_nr);
1528 
1529 	return acpi_graph_get_child_prop_value(fwnode, "endpoint", endpoint_nr);
1530 }
1531 
1532 static bool acpi_fwnode_device_is_available(const struct fwnode_handle *fwnode)
1533 {
1534 	if (!is_acpi_device_node(fwnode))
1535 		return true;
1536 
1537 	return acpi_device_is_present(to_acpi_device_node(fwnode));
1538 }
1539 
1540 static const void *
1541 acpi_fwnode_device_get_match_data(const struct fwnode_handle *fwnode,
1542 				  const struct device *dev)
1543 {
1544 	return acpi_device_get_match_data(dev);
1545 }
1546 
1547 static bool acpi_fwnode_device_dma_supported(const struct fwnode_handle *fwnode)
1548 {
1549 	return acpi_dma_supported(to_acpi_device_node(fwnode));
1550 }
1551 
1552 static enum dev_dma_attr
1553 acpi_fwnode_device_get_dma_attr(const struct fwnode_handle *fwnode)
1554 {
1555 	return acpi_get_dma_attr(to_acpi_device_node(fwnode));
1556 }
1557 
1558 static bool acpi_fwnode_property_present(const struct fwnode_handle *fwnode,
1559 					 const char *propname)
1560 {
1561 	return !acpi_node_prop_get(fwnode, propname, NULL);
1562 }
1563 
1564 static int
1565 acpi_fwnode_property_read_int_array(const struct fwnode_handle *fwnode,
1566 				    const char *propname,
1567 				    unsigned int elem_size, void *val,
1568 				    size_t nval)
1569 {
1570 	enum dev_prop_type type;
1571 
1572 	switch (elem_size) {
1573 	case sizeof(u8):
1574 		type = DEV_PROP_U8;
1575 		break;
1576 	case sizeof(u16):
1577 		type = DEV_PROP_U16;
1578 		break;
1579 	case sizeof(u32):
1580 		type = DEV_PROP_U32;
1581 		break;
1582 	case sizeof(u64):
1583 		type = DEV_PROP_U64;
1584 		break;
1585 	default:
1586 		return -ENXIO;
1587 	}
1588 
1589 	return acpi_node_prop_read(fwnode, propname, type, val, nval);
1590 }
1591 
1592 static int
1593 acpi_fwnode_property_read_string_array(const struct fwnode_handle *fwnode,
1594 				       const char *propname, const char **val,
1595 				       size_t nval)
1596 {
1597 	return acpi_node_prop_read(fwnode, propname, DEV_PROP_STRING,
1598 				   val, nval);
1599 }
1600 
1601 static int
1602 acpi_fwnode_get_reference_args(const struct fwnode_handle *fwnode,
1603 			       const char *prop, const char *nargs_prop,
1604 			       unsigned int args_count, unsigned int index,
1605 			       struct fwnode_reference_args *args)
1606 {
1607 	return __acpi_node_get_property_reference(fwnode, prop, index,
1608 						  args_count, args);
1609 }
1610 
1611 static const char *acpi_fwnode_get_name(const struct fwnode_handle *fwnode)
1612 {
1613 	const struct acpi_device *adev;
1614 	struct fwnode_handle *parent;
1615 
1616 	/* Is this the root node? */
1617 	parent = fwnode_get_parent(fwnode);
1618 	if (!parent)
1619 		return "\\";
1620 
1621 	fwnode_handle_put(parent);
1622 
1623 	if (is_acpi_data_node(fwnode)) {
1624 		const struct acpi_data_node *dn = to_acpi_data_node(fwnode);
1625 
1626 		return dn->name;
1627 	}
1628 
1629 	adev = to_acpi_device_node(fwnode);
1630 	if (WARN_ON(!adev))
1631 		return NULL;
1632 
1633 	return acpi_device_bid(adev);
1634 }
1635 
1636 static const char *
1637 acpi_fwnode_get_name_prefix(const struct fwnode_handle *fwnode)
1638 {
1639 	struct fwnode_handle *parent;
1640 
1641 	/* Is this the root node? */
1642 	parent = fwnode_get_parent(fwnode);
1643 	if (!parent)
1644 		return "";
1645 
1646 	/* Is this 2nd node from the root? */
1647 	parent = fwnode_get_next_parent(parent);
1648 	if (!parent)
1649 		return "";
1650 
1651 	fwnode_handle_put(parent);
1652 
1653 	/* ACPI device or data node. */
1654 	return ".";
1655 }
1656 
1657 static struct fwnode_handle *
1658 acpi_fwnode_get_parent(struct fwnode_handle *fwnode)
1659 {
1660 	return acpi_node_get_parent(fwnode);
1661 }
1662 
1663 static int acpi_fwnode_graph_parse_endpoint(const struct fwnode_handle *fwnode,
1664 					    struct fwnode_endpoint *endpoint)
1665 {
1666 	struct fwnode_handle *port_fwnode = fwnode_get_parent(fwnode);
1667 
1668 	endpoint->local_fwnode = fwnode;
1669 
1670 	if (fwnode_property_read_u32(port_fwnode, "reg", &endpoint->port))
1671 		fwnode_property_read_u32(port_fwnode, "port", &endpoint->port);
1672 	if (fwnode_property_read_u32(fwnode, "reg", &endpoint->id))
1673 		fwnode_property_read_u32(fwnode, "endpoint", &endpoint->id);
1674 
1675 	return 0;
1676 }
1677 
1678 static int acpi_fwnode_irq_get(const struct fwnode_handle *fwnode,
1679 			       unsigned int index)
1680 {
1681 	struct resource res;
1682 	int ret;
1683 
1684 	ret = acpi_irq_get(ACPI_HANDLE_FWNODE(fwnode), index, &res);
1685 	if (ret)
1686 		return ret;
1687 
1688 	return res.start;
1689 }
1690 
1691 #define DECLARE_ACPI_FWNODE_OPS(ops) \
1692 	const struct fwnode_operations ops = {				\
1693 		.device_is_available = acpi_fwnode_device_is_available, \
1694 		.device_get_match_data = acpi_fwnode_device_get_match_data, \
1695 		.device_dma_supported =				\
1696 			acpi_fwnode_device_dma_supported,		\
1697 		.device_get_dma_attr = acpi_fwnode_device_get_dma_attr,	\
1698 		.property_present = acpi_fwnode_property_present,	\
1699 		.property_read_bool = acpi_fwnode_property_present,	\
1700 		.property_read_int_array =				\
1701 			acpi_fwnode_property_read_int_array,		\
1702 		.property_read_string_array =				\
1703 			acpi_fwnode_property_read_string_array,		\
1704 		.get_parent = acpi_node_get_parent,			\
1705 		.get_next_child_node = acpi_get_next_subnode,		\
1706 		.get_named_child_node = acpi_fwnode_get_named_child_node, \
1707 		.get_name = acpi_fwnode_get_name,			\
1708 		.get_name_prefix = acpi_fwnode_get_name_prefix,		\
1709 		.get_reference_args = acpi_fwnode_get_reference_args,	\
1710 		.graph_get_next_endpoint =				\
1711 			acpi_graph_get_next_endpoint,			\
1712 		.graph_get_remote_endpoint =				\
1713 			acpi_graph_get_remote_endpoint,			\
1714 		.graph_get_port_parent = acpi_fwnode_get_parent,	\
1715 		.graph_parse_endpoint = acpi_fwnode_graph_parse_endpoint, \
1716 		.irq_get = acpi_fwnode_irq_get,				\
1717 	};								\
1718 	EXPORT_SYMBOL_GPL(ops)
1719 
1720 DECLARE_ACPI_FWNODE_OPS(acpi_device_fwnode_ops);
1721 DECLARE_ACPI_FWNODE_OPS(acpi_data_fwnode_ops);
1722 const struct fwnode_operations acpi_static_fwnode_ops;
1723 
1724 bool is_acpi_device_node(const struct fwnode_handle *fwnode)
1725 {
1726 	return !IS_ERR_OR_NULL(fwnode) &&
1727 		fwnode->ops == &acpi_device_fwnode_ops;
1728 }
1729 EXPORT_SYMBOL(is_acpi_device_node);
1730 
1731 bool is_acpi_data_node(const struct fwnode_handle *fwnode)
1732 {
1733 	return !IS_ERR_OR_NULL(fwnode) && fwnode->ops == &acpi_data_fwnode_ops;
1734 }
1735 EXPORT_SYMBOL(is_acpi_data_node);
1736