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