drivers/acpi/property.c

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