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                         struct acpi_device *parent;
 308
 309                         parent = acpi_dev_parent(adev);
 310                         if (parent && parent->flags.of_compatible_ok)
 311                                 goto out;
 312
 313                         return;
 314                 }
 315         }
 316         adev->data.of_compatible = of_compatible;
 317
 318  out:
 319         adev->flags.of_compatible_ok = 1;
 320 }
 321
 322 static bool acpi_is_property_guid(const guid_t *guid)
 323 {
 324         int i;
 325
 326         for (i = 0; i < ARRAY_SIZE(prp_guids); i++) {
 327                 if (guid_equal(guid, &prp_guids[i]))
 328                         return true;
 329         }
 330
 331         return false;
 332 }
 333
 334 struct acpi_device_properties *
 335 acpi_data_add_props(struct acpi_device_data *data, const guid_t *guid,
 336                     union acpi_object *properties)
 337 {
 338         struct acpi_device_properties *props;
 339
 340         props = kzalloc(sizeof(*props), GFP_KERNEL);
 341         if (props) {
 342                 INIT_LIST_HEAD(&props->list);
 343                 props->guid = guid;
 344                 props->properties = properties;
 345                 list_add_tail(&props->list, &data->properties);
 346         }
 347
 348         return props;
 349 }
 350
 351 static void acpi_nondev_subnode_tag(acpi_handle handle, void *context)
 352 {
 353 }
 354
 355 static void acpi_untie_nondev_subnodes(struct acpi_device_data *data)
 356 {
 357         struct acpi_data_node *dn;
 358
 359         list_for_each_entry(dn, &data->subnodes, sibling) {
 360                 acpi_detach_data(dn->handle, acpi_nondev_subnode_tag);
 361
 362                 acpi_untie_nondev_subnodes(&dn->data);
 363         }
 364 }
 365
 366 static bool acpi_tie_nondev_subnodes(struct acpi_device_data *data)
 367 {
 368         struct acpi_data_node *dn;
 369
 370         list_for_each_entry(dn, &data->subnodes, sibling) {
 371                 acpi_status status;
 372                 bool ret;
 373
 374                 status = acpi_attach_data(dn->handle, acpi_nondev_subnode_tag, dn);
 375                 if (ACPI_FAILURE(status) && status != AE_ALREADY_EXISTS) {
 376                         acpi_handle_err(dn->handle, "Can't tag data node\n");
 377                         return false;
 378                 }
 379
 380                 ret = acpi_tie_nondev_subnodes(&dn->data);
 381                 if (!ret)
 382                         return ret;
 383         }
 384
 385         return true;
 386 }
 387
 388 static void acpi_data_add_buffer_props(acpi_handle handle,
 389                                        struct acpi_device_data *data,
 390                                        union acpi_object *properties)
 391 {
 392         struct acpi_device_properties *props;
 393         union acpi_object *package;
 394         size_t alloc_size;
 395         unsigned int i;
 396         u32 *count;
 397
 398         if (check_mul_overflow((size_t)properties->package.count,
 399                                sizeof(*package) + sizeof(void *),
 400                                &alloc_size) ||
 401             check_add_overflow(sizeof(*props) + sizeof(*package), alloc_size,
 402                                &alloc_size)) {
 403                 acpi_handle_warn(handle,
 404                                  "can't allocate memory for %u buffer props",
 405                                  properties->package.count);
 406                 return;
 407         }
 408
 409         props = kvzalloc(alloc_size, GFP_KERNEL);
 410         if (!props)
 411                 return;
 412
 413         props->guid = &buffer_prop_guid;
 414         props->bufs = (void *)(props + 1);
 415         props->properties = (void *)(props->bufs + properties->package.count);
 416
 417         /* Outer package */
 418         package = props->properties;
 419         package->type = ACPI_TYPE_PACKAGE;
 420         package->package.elements = package + 1;
 421         count = &package->package.count;
 422         *count = 0;
 423
 424         /* Inner packages */
 425         package++;
 426
 427         for (i = 0; i < properties->package.count; i++) {
 428                 struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
 429                 union acpi_object *property = &properties->package.elements[i];
 430                 union acpi_object *prop, *obj, *buf_obj;
 431                 acpi_status status;
 432
 433                 if (property->type != ACPI_TYPE_PACKAGE ||
 434                     property->package.count != 2) {
 435                         acpi_handle_warn(handle,
 436                                          "buffer property %u has %u entries\n",
 437                                          i, property->package.count);
 438                         continue;
 439                 }
 440
 441                 prop = &property->package.elements[0];
 442                 obj = &property->package.elements[1];
 443
 444                 if (prop->type != ACPI_TYPE_STRING ||
 445                     obj->type != ACPI_TYPE_STRING) {
 446                         acpi_handle_warn(handle,
 447                                          "wrong object types %u and %u\n",
 448                                          prop->type, obj->type);
 449                         continue;
 450                 }
 451
 452                 status = acpi_evaluate_object_typed(handle, obj->string.pointer,
 453                                                     NULL, &buf,
 454                                                     ACPI_TYPE_BUFFER);
 455                 if (ACPI_FAILURE(status)) {
 456                         acpi_handle_warn(handle,
 457                                          "can't evaluate \"%*pE\" as buffer\n",
 458                                          obj->string.length,
 459                                          obj->string.pointer);
 460                         continue;
 461                 }
 462
 463                 package->type = ACPI_TYPE_PACKAGE;
 464                 package->package.elements = prop;
 465                 package->package.count = 2;
 466
 467                 buf_obj = buf.pointer;
 468
 469                 /* Replace the string object with a buffer object */
 470                 obj->type = ACPI_TYPE_BUFFER;
 471                 obj->buffer.length = buf_obj->buffer.length;
 472                 obj->buffer.pointer = buf_obj->buffer.pointer;
 473
 474                 props->bufs[i] = buf.pointer;
 475                 package++;
 476                 (*count)++;
 477         }
 478
 479         if (*count)
 480                 list_add(&props->list, &data->properties);
 481         else
 482                 kvfree(props);
 483 }
 484
 485 static bool acpi_extract_properties(acpi_handle scope, union acpi_object *desc,
 486                                     struct acpi_device_data *data)
 487 {
 488         int i;
 489
 490         if (desc->package.count % 2)
 491                 return false;
 492
 493         /* Look for the device properties GUID. */
 494         for (i = 0; i < desc->package.count; i += 2) {
 495                 const union acpi_object *guid;
 496                 union acpi_object *properties;
 497
 498                 guid = &desc->package.elements[i];
 499                 properties = &desc->package.elements[i + 1];
 500
 501                 /*
 502                  * The first element must be a GUID and the second one must be
 503                  * a package.
 504                  */
 505                 if (guid->type != ACPI_TYPE_BUFFER ||
 506                     guid->buffer.length != 16 ||
 507                     properties->type != ACPI_TYPE_PACKAGE)
 508                         break;
 509
 510                 if (guid_equal((guid_t *)guid->buffer.pointer,
 511                                &buffer_prop_guid)) {
 512                         acpi_data_add_buffer_props(scope, data, properties);
 513                         continue;
 514                 }
 515
 516                 if (!acpi_is_property_guid((guid_t *)guid->buffer.pointer))
 517                         continue;
 518
 519                 /*
 520                  * We found the matching GUID. Now validate the format of the
 521                  * package immediately following it.
 522                  */
 523                 if (!acpi_properties_format_valid(properties))
 524                         continue;
 525
 526                 acpi_data_add_props(data, (const guid_t *)guid->buffer.pointer,
 527                                     properties);
 528         }
 529
 530         return !list_empty(&data->properties);
 531 }
 532
 533 void acpi_init_properties(struct acpi_device *adev)
 534 {
 535         struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
 536         struct acpi_hardware_id *hwid;
 537         acpi_status status;
 538         bool acpi_of = false;
 539
 540         INIT_LIST_HEAD(&adev->data.properties);
 541         INIT_LIST_HEAD(&adev->data.subnodes);
 542
 543         if (!adev->handle)
 544                 return;
 545
 546         /*
 547          * Check if ACPI_DT_NAMESPACE_HID is present and inthat case we fill in
 548          * Device Tree compatible properties for this device.
 549          */
 550         list_for_each_entry(hwid, &adev->pnp.ids, list) {
 551                 if (!strcmp(hwid->id, ACPI_DT_NAMESPACE_HID)) {
 552                         acpi_of = true;
 553                         break;
 554                 }
 555         }
 556
 557         status = acpi_evaluate_object_typed(adev->handle, "_DSD", NULL, &buf,
 558                                             ACPI_TYPE_PACKAGE);
 559         if (ACPI_FAILURE(status))
 560                 goto out;
 561
 562         if (acpi_extract_properties(adev->handle, buf.pointer, &adev->data)) {
 563                 adev->data.pointer = buf.pointer;
 564                 if (acpi_of)
 565                         acpi_init_of_compatible(adev);
 566         }
 567         if (acpi_enumerate_nondev_subnodes(adev->handle, buf.pointer,
 568                                         &adev->data, acpi_fwnode_handle(adev)))
 569                 adev->data.pointer = buf.pointer;
 570
 571         if (!adev->data.pointer) {
 572                 acpi_handle_debug(adev->handle, "Invalid _DSD data, skipping\n");
 573                 ACPI_FREE(buf.pointer);
 574         } else {
 575                 if (!acpi_tie_nondev_subnodes(&adev->data))
 576                         acpi_untie_nondev_subnodes(&adev->data);
 577         }
 578
 579  out:
 580         if (acpi_of && !adev->flags.of_compatible_ok)
 581                 acpi_handle_info(adev->handle,
 582                          ACPI_DT_NAMESPACE_HID " requires 'compatible' property\n");
 583
 584         if (!adev->data.pointer)
 585                 acpi_extract_apple_properties(adev);
 586 }
 587
 588 static void acpi_free_device_properties(struct list_head *list)
 589 {
 590         struct acpi_device_properties *props, *tmp;
 591
 592         list_for_each_entry_safe(props, tmp, list, list) {
 593                 u32 i;
 594
 595                 list_del(&props->list);
 596                 /* Buffer data properties were separately allocated */
 597                 if (props->bufs)
 598                         for (i = 0; i < props->properties->package.count; i++)
 599                                 ACPI_FREE(props->bufs[i]);
 600                 kvfree(props);
 601         }
 602 }
 603
 604 static void acpi_destroy_nondev_subnodes(struct list_head *list)
 605 {
 606         struct acpi_data_node *dn, *next;
 607
 608         if (list_empty(list))
 609                 return;
 610
 611         list_for_each_entry_safe_reverse(dn, next, list, sibling) {
 612                 acpi_destroy_nondev_subnodes(&dn->data.subnodes);
 613                 wait_for_completion(&dn->kobj_done);
 614                 list_del(&dn->sibling);
 615                 ACPI_FREE((void *)dn->data.pointer);
 616                 acpi_free_device_properties(&dn->data.properties);
 617                 kfree(dn);
 618         }
 619 }
 620
 621 void acpi_free_properties(struct acpi_device *adev)
 622 {
 623         acpi_untie_nondev_subnodes(&adev->data);
 624         acpi_destroy_nondev_subnodes(&adev->data.subnodes);
 625         ACPI_FREE((void *)adev->data.pointer);
 626         adev->data.of_compatible = NULL;
 627         adev->data.pointer = NULL;
 628         acpi_free_device_properties(&adev->data.properties);
 629 }
 630
 631 /**
 632  * acpi_data_get_property - return an ACPI property with given name
 633  * @data: ACPI device deta object to get the property from
 634  * @name: Name of the property
 635  * @type: Expected property type
 636  * @obj: Location to store the property value (if not %NULL)
 637  *
 638  * Look up a property with @name and store a pointer to the resulting ACPI
 639  * object at the location pointed to by @obj if found.
 640  *
 641  * Callers must not attempt to free the returned objects.  These objects will be
 642  * freed by the ACPI core automatically during the removal of @data.
 643  *
 644  * Return: %0 if property with @name has been found (success),
 645  *         %-EINVAL if the arguments are invalid,
 646  *         %-EINVAL if the property doesn't exist,
 647  *         %-EPROTO if the property value type doesn't match @type.
 648  */
 649 static int acpi_data_get_property(const struct acpi_device_data *data,
 650                                   const char *name, acpi_object_type type,
 651                                   const union acpi_object **obj)
 652 {
 653         const struct acpi_device_properties *props;
 654
 655         if (!data || !name)
 656                 return -EINVAL;
 657
 658         if (!data->pointer || list_empty(&data->properties))
 659                 return -EINVAL;
 660
 661         list_for_each_entry(props, &data->properties, list) {
 662                 const union acpi_object *properties;
 663                 unsigned int i;
 664
 665                 properties = props->properties;
 666                 for (i = 0; i < properties->package.count; i++) {
 667                         const union acpi_object *propname, *propvalue;
 668                         const union acpi_object *property;
 669
 670                         property = &properties->package.elements[i];
 671
 672                         propname = &property->package.elements[0];
 673                         propvalue = &property->package.elements[1];
 674
 675                         if (!strcmp(name, propname->string.pointer)) {
 676                                 if (type != ACPI_TYPE_ANY &&
 677                                     propvalue->type != type)
 678                                         return -EPROTO;
 679                                 if (obj)
 680                                         *obj = propvalue;
 681
 682                                 return 0;
 683                         }
 684                 }
 685         }
 686         return -EINVAL;
 687 }
 688
 689 /**
 690  * acpi_dev_get_property - return an ACPI property with given name.
 691  * @adev: ACPI device to get the property from.
 692  * @name: Name of the property.
 693  * @type: Expected property type.
 694  * @obj: Location to store the property value (if not %NULL).
 695  */
 696 int acpi_dev_get_property(const struct acpi_device *adev, const char *name,
 697                           acpi_object_type type, const union acpi_object **obj)
 698 {
 699         return adev ? acpi_data_get_property(&adev->data, name, type, obj) : -EINVAL;
 700 }
 701 EXPORT_SYMBOL_GPL(acpi_dev_get_property);
 702
 703 static const struct acpi_device_data *
 704 acpi_device_data_of_node(const struct fwnode_handle *fwnode)
 705 {
 706         if (is_acpi_device_node(fwnode)) {
 707                 const struct acpi_device *adev = to_acpi_device_node(fwnode);
 708                 return &adev->data;
 709         }
 710         if (is_acpi_data_node(fwnode)) {
 711                 const struct acpi_data_node *dn = to_acpi_data_node(fwnode);
 712                 return &dn->data;
 713         }
 714         return NULL;
 715 }
 716
 717 /**
 718  * acpi_node_prop_get - return an ACPI property with given name.
 719  * @fwnode: Firmware node to get the property from.
 720  * @propname: Name of the property.
 721  * @valptr: Location to store a pointer to the property value (if not %NULL).
 722  */
 723 int acpi_node_prop_get(const struct fwnode_handle *fwnode,
 724                        const char *propname, void **valptr)
 725 {
 726         return acpi_data_get_property(acpi_device_data_of_node(fwnode),
 727                                       propname, ACPI_TYPE_ANY,
 728                                       (const union acpi_object **)valptr);
 729 }
 730
 731 /**
 732  * acpi_data_get_property_array - return an ACPI array property with given name
 733  * @data: ACPI data object to get the property from
 734  * @name: Name of the property
 735  * @type: Expected type of array elements
 736  * @obj: Location to store a pointer to the property value (if not NULL)
 737  *
 738  * Look up an array property with @name and store a pointer to the resulting
 739  * ACPI object at the location pointed to by @obj if found.
 740  *
 741  * Callers must not attempt to free the returned objects.  Those objects will be
 742  * freed by the ACPI core automatically during the removal of @data.
 743  *
 744  * Return: %0 if array property (package) with @name has been found (success),
 745  *         %-EINVAL if the arguments are invalid,
 746  *         %-EINVAL if the property doesn't exist,
 747  *         %-EPROTO if the property is not a package or the type of its elements
 748  *           doesn't match @type.
 749  */
 750 static int acpi_data_get_property_array(const struct acpi_device_data *data,
 751                                         const char *name,
 752                                         acpi_object_type type,
 753                                         const union acpi_object **obj)
 754 {
 755         const union acpi_object *prop;
 756         int ret, i;
 757
 758         ret = acpi_data_get_property(data, name, ACPI_TYPE_PACKAGE, &prop);
 759         if (ret)
 760                 return ret;
 761
 762         if (type != ACPI_TYPE_ANY) {
 763                 /* Check that all elements are of correct type. */
 764                 for (i = 0; i < prop->package.count; i++)
 765                         if (prop->package.elements[i].type != type)
 766                                 return -EPROTO;
 767         }
 768         if (obj)
 769                 *obj = prop;
 770
 771         return 0;
 772 }
 773
 774 static struct fwnode_handle *
 775 acpi_fwnode_get_named_child_node(const struct fwnode_handle *fwnode,
 776                                  const char *childname)
 777 {
 778         struct fwnode_handle *child;
 779
 780         fwnode_for_each_child_node(fwnode, child) {
 781                 if (is_acpi_data_node(child)) {
 782                         if (acpi_data_node_match(child, childname))
 783                                 return child;
 784                         continue;
 785                 }
 786
 787                 if (!strncmp(acpi_device_bid(to_acpi_device_node(child)),
 788                              childname, ACPI_NAMESEG_SIZE))
 789                         return child;
 790         }
 791
 792         return NULL;
 793 }
 794
 795 static int acpi_get_ref_args(struct fwnode_reference_args *args,
 796                              struct fwnode_handle *ref_fwnode,
 797                              const union acpi_object **element,
 798                              const union acpi_object *end, size_t num_args)
 799 {
 800         u32 nargs = 0, i;
 801
 802         /*
 803          * Find the referred data extension node under the
 804          * referred device node.
 805          */
 806         for (; *element < end && (*element)->type == ACPI_TYPE_STRING;
 807              (*element)++) {
 808                 const char *child_name = (*element)->string.pointer;
 809
 810                 ref_fwnode = acpi_fwnode_get_named_child_node(ref_fwnode, child_name);
 811                 if (!ref_fwnode)
 812                         return -EINVAL;
 813         }
 814
 815         /*
 816          * Assume the following integer elements are all args. Stop counting on
 817          * the first reference or end of the package arguments. In case of
 818          * neither reference, nor integer, return an error, we can't parse it.
 819          */
 820         for (i = 0; (*element) + i < end && i < num_args; i++) {
 821                 acpi_object_type type = (*element)[i].type;
 822
 823                 if (type == ACPI_TYPE_LOCAL_REFERENCE)
 824                         break;
 825
 826                 if (type == ACPI_TYPE_INTEGER)
 827                         nargs++;
 828                 else
 829                         return -EINVAL;
 830         }
 831
 832         if (nargs > NR_FWNODE_REFERENCE_ARGS)
 833                 return -EINVAL;
 834
 835         if (args) {
 836                 args->fwnode = ref_fwnode;
 837                 args->nargs = nargs;
 838                 for (i = 0; i < nargs; i++)
 839                         args->args[i] = (*element)[i].integer.value;
 840         }
 841
 842         (*element) += nargs;
 843
 844         return 0;
 845 }
 846
 847 /**
 848  * __acpi_node_get_property_reference - returns handle to the referenced object
 849  * @fwnode: Firmware node to get the property from
 850  * @propname: Name of the property
 851  * @index: Index of the reference to return
 852  * @num_args: Maximum number of arguments after each reference
 853  * @args: Location to store the returned reference with optional arguments
 854  *
 855  * Find property with @name, verifify that it is a package containing at least
 856  * one object reference and if so, store the ACPI device object pointer to the
 857  * target object in @args->adev.  If the reference includes arguments, store
 858  * them in the @args->args[] array.
 859  *
 860  * If there's more than one reference in the property value package, @index is
 861  * used to select the one to return.
 862  *
 863  * It is possible to leave holes in the property value set like in the
 864  * example below:
 865  *
 866  * Package () {
 867  *     "cs-gpios",
 868  *     Package () {
 869  *        ^GPIO, 19, 0, 0,
 870  *        ^GPIO, 20, 0, 0,
 871  *        0,
 872  *        ^GPIO, 21, 0, 0,
 873  *     }
 874  * }
 875  *
 876  * Calling this function with index %2 or index %3 return %-ENOENT. If the
 877  * property does not contain any more values %-ENOENT is returned. The NULL
 878  * entry must be single integer and preferably contain value %0.
 879  *
 880  * Return: %0 on success, negative error code on failure.
 881  */
 882 int __acpi_node_get_property_reference(const struct fwnode_handle *fwnode,
 883         const char *propname, size_t index, size_t num_args,
 884         struct fwnode_reference_args *args)
 885 {
 886         const union acpi_object *element, *end;
 887         const union acpi_object *obj;
 888         const struct acpi_device_data *data;
 889         struct acpi_device *device;
 890         int ret, idx = 0;
 891
 892         data = acpi_device_data_of_node(fwnode);
 893         if (!data)
 894                 return -ENOENT;
 895
 896         ret = acpi_data_get_property(data, propname, ACPI_TYPE_ANY, &obj);
 897         if (ret)
 898                 return ret == -EINVAL ? -ENOENT : -EINVAL;
 899
 900         switch (obj->type) {
 901         case ACPI_TYPE_LOCAL_REFERENCE:
 902                 /* Plain single reference without arguments. */
 903                 if (index)
 904                         return -ENOENT;
 905
 906                 device = acpi_fetch_acpi_dev(obj->reference.handle);
 907                 if (!device)
 908                         return -EINVAL;
 909
 910                 args->fwnode = acpi_fwnode_handle(device);
 911                 args->nargs = 0;
 912                 return 0;
 913         case ACPI_TYPE_PACKAGE:
 914                 /*
 915                  * If it is not a single reference, then it is a package of
 916                  * references followed by number of ints as follows:
 917                  *
 918                  *  Package () { REF, INT, REF, INT, INT }
 919                  *
 920                  * The index argument is then used to determine which reference
 921                  * the caller wants (along with the arguments).
 922                  */
 923                 break;
 924         default:
 925                 return -EINVAL;
 926         }
 927
 928         if (index >= obj->package.count)
 929                 return -ENOENT;
 930
 931         element = obj->package.elements;
 932         end = element + obj->package.count;
 933
 934         while (element < end) {
 935                 switch (element->type) {
 936                 case ACPI_TYPE_LOCAL_REFERENCE:
 937                         device = acpi_fetch_acpi_dev(element->reference.handle);
 938                         if (!device)
 939                                 return -EINVAL;
 940
 941                         element++;
 942
 943                         ret = acpi_get_ref_args(idx == index ? args : NULL,
 944                                                 acpi_fwnode_handle(device),
 945                                                 &element, end, num_args);
 946                         if (ret < 0)
 947                                 return ret;
 948
 949                         if (idx == index)
 950                                 return 0;
 951
 952                         break;
 953                 case ACPI_TYPE_INTEGER:
 954                         if (idx == index)
 955                                 return -ENOENT;
 956                         element++;
 957                         break;
 958                 default:
 959                         return -EINVAL;
 960                 }
 961
 962                 idx++;
 963         }
 964
 965         return -ENOENT;
 966 }
 967 EXPORT_SYMBOL_GPL(__acpi_node_get_property_reference);
 968
 969 static int acpi_data_prop_read_single(const struct acpi_device_data *data,
 970                                       const char *propname,
 971                                       enum dev_prop_type proptype, void *val)
 972 {
 973         const union acpi_object *obj;
 974         int ret;
 975
 976         if (proptype >= DEV_PROP_U8 && proptype <= DEV_PROP_U64) {
 977                 ret = acpi_data_get_property(data, propname, ACPI_TYPE_INTEGER, &obj);
 978                 if (ret)
 979                         return ret;
 980
 981                 switch (proptype) {
 982                 case DEV_PROP_U8:
 983                         if (obj->integer.value > U8_MAX)
 984                                 return -EOVERFLOW;
 985
 986                         if (val)
 987                                 *(u8 *)val = obj->integer.value;
 988
 989                         break;
 990                 case DEV_PROP_U16:
 991                         if (obj->integer.value > U16_MAX)
 992                                 return -EOVERFLOW;
 993
 994                         if (val)
 995                                 *(u16 *)val = obj->integer.value;
 996
 997                         break;
 998                 case DEV_PROP_U32:
 999                         if (obj->integer.value > U32_MAX)
1000                                 return -EOVERFLOW;
1001
1002                         if (val)
1003                                 *(u32 *)val = obj->integer.value;
1004
1005                         break;
1006                 default:
1007                         if (val)
1008                                 *(u64 *)val = obj->integer.value;
1009
1010                         break;
1011                 }
1012
1013                 if (!val)
1014                         return 1;
1015         } else if (proptype == DEV_PROP_STRING) {
1016                 ret = acpi_data_get_property(data, propname, ACPI_TYPE_STRING, &obj);
1017                 if (ret)
1018                         return ret;
1019
1020                 if (val)
1021                         *(char **)val = obj->string.pointer;
1022
1023                 return 1;
1024         } else {
1025                 ret = -EINVAL;
1026         }
1027         return ret;
1028 }
1029
1030 #define acpi_copy_property_array_uint(items, val, nval)                 \
1031         ({                                                              \
1032                 typeof(items) __items = items;                          \
1033                 typeof(val) __val = val;                                \
1034                 typeof(nval) __nval = nval;                             \
1035                 size_t i;                                               \
1036                 int ret = 0;                                            \
1037                                                                         \
1038                 for (i = 0; i < __nval; i++) {                          \
1039                         if (__items->type == ACPI_TYPE_BUFFER) {        \
1040                                 __val[i] = __items->buffer.pointer[i];  \
1041                                 continue;                               \
1042                         }                                               \
1043                         if (__items[i].type != ACPI_TYPE_INTEGER) {     \
1044                                 ret = -EPROTO;                          \
1045                                 break;                                  \
1046                         }                                               \
1047                         if (__items[i].integer.value > _Generic(__val,  \
1048                                                                 u8 *: U8_MAX, \
1049                                                                 u16 *: U16_MAX, \
1050                                                                 u32 *: U32_MAX, \
1051                                                                 u64 *: U64_MAX)) { \
1052                                 ret = -EOVERFLOW;                       \
1053                                 break;                                  \
1054                         }                                               \
1055                                                                         \
1056                         __val[i] = __items[i].integer.value;            \
1057                 }                                                       \
1058                 ret;                                                    \
1059         })
1060
1061 static int acpi_copy_property_array_string(const union acpi_object *items,
1062                                            char **val, size_t nval)
1063 {
1064         int i;
1065
1066         for (i = 0; i < nval; i++) {
1067                 if (items[i].type != ACPI_TYPE_STRING)
1068                         return -EPROTO;
1069
1070                 val[i] = items[i].string.pointer;
1071         }
1072         return nval;
1073 }
1074
1075 static int acpi_data_prop_read(const struct acpi_device_data *data,
1076                                const char *propname,
1077                                enum dev_prop_type proptype,
1078                                void *val, size_t nval)
1079 {
1080         const union acpi_object *obj;
1081         const union acpi_object *items;
1082         int ret;
1083
1084         if (nval == 1 || !val) {
1085                 ret = acpi_data_prop_read_single(data, propname, proptype, val);
1086                 /*
1087                  * The overflow error means that the property is there and it is
1088                  * single-value, but its type does not match, so return.
1089                  */
1090                 if (ret >= 0 || ret == -EOVERFLOW)
1091                         return ret;
1092
1093                 /*
1094                  * Reading this property as a single-value one failed, but its
1095                  * value may still be represented as one-element array, so
1096                  * continue.
1097                  */
1098         }
1099
1100         ret = acpi_data_get_property_array(data, propname, ACPI_TYPE_ANY, &obj);
1101         if (ret && proptype >= DEV_PROP_U8 && proptype <= DEV_PROP_U64)
1102                 ret = acpi_data_get_property(data, propname, ACPI_TYPE_BUFFER,
1103                                              &obj);
1104         if (ret)
1105                 return ret;
1106
1107         if (!val) {
1108                 if (obj->type == ACPI_TYPE_BUFFER)
1109                         return obj->buffer.length;
1110
1111                 return obj->package.count;
1112         }
1113
1114         switch (proptype) {
1115         case DEV_PROP_STRING:
1116                 break;
1117         case DEV_PROP_U8 ... DEV_PROP_U64:
1118                 if (obj->type == ACPI_TYPE_BUFFER) {
1119                         if (nval > obj->buffer.length)
1120                                 return -EOVERFLOW;
1121                         break;
1122                 }
1123                 fallthrough;
1124         default:
1125                 if (nval > obj->package.count)
1126                         return -EOVERFLOW;
1127                 break;
1128         }
1129         if (nval == 0)
1130                 return -EINVAL;
1131
1132         if (obj->type != ACPI_TYPE_BUFFER)
1133                 items = obj->package.elements;
1134         else
1135                 items = obj;
1136
1137         switch (proptype) {
1138         case DEV_PROP_U8:
1139                 ret = acpi_copy_property_array_uint(items, (u8 *)val, nval);
1140                 break;
1141         case DEV_PROP_U16:
1142                 ret = acpi_copy_property_array_uint(items, (u16 *)val, nval);
1143                 break;
1144         case DEV_PROP_U32:
1145                 ret = acpi_copy_property_array_uint(items, (u32 *)val, nval);
1146                 break;
1147         case DEV_PROP_U64:
1148                 ret = acpi_copy_property_array_uint(items, (u64 *)val, nval);
1149                 break;
1150         case DEV_PROP_STRING:
1151                 ret = acpi_copy_property_array_string(
1152                         items, (char **)val,
1153                         min_t(u32, nval, obj->package.count));
1154                 break;
1155         default:
1156                 ret = -EINVAL;
1157                 break;
1158         }
1159         return ret;
1160 }
1161
1162 /**
1163  * acpi_node_prop_read - retrieve the value of an ACPI property with given name.
1164  * @fwnode: Firmware node to get the property from.
1165  * @propname: Name of the property.
1166  * @proptype: Expected property type.
1167  * @val: Location to store the property value (if not %NULL).
1168  * @nval: Size of the array pointed to by @val.
1169  *
1170  * If @val is %NULL, return the number of array elements comprising the value
1171  * of the property.  Otherwise, read at most @nval values to the array at the
1172  * location pointed to by @val.
1173  */
1174 static int acpi_node_prop_read(const struct fwnode_handle *fwnode,
1175                                const char *propname, enum dev_prop_type proptype,
1176                                void *val, size_t nval)
1177 {
1178         return acpi_data_prop_read(acpi_device_data_of_node(fwnode),
1179                                    propname, proptype, val, nval);
1180 }
1181
1182 static int stop_on_next(struct acpi_device *adev, void *data)
1183 {
1184         struct acpi_device **ret_p = data;
1185
1186         if (!*ret_p) {
1187                 *ret_p = adev;
1188                 return 1;
1189         }
1190
1191         /* Skip until the "previous" object is found. */
1192         if (*ret_p == adev)
1193                 *ret_p = NULL;
1194
1195         return 0;
1196 }
1197
1198 /**
1199  * acpi_get_next_subnode - Return the next child node handle for a fwnode
1200  * @fwnode: Firmware node to find the next child node for.
1201  * @child: Handle to one of the device's child nodes or a null handle.
1202  */
1203 struct fwnode_handle *acpi_get_next_subnode(const struct fwnode_handle *fwnode,
1204                                             struct fwnode_handle *child)
1205 {
1206         struct acpi_device *adev = to_acpi_device_node(fwnode);
1207
1208         if ((!child || is_acpi_device_node(child)) && adev) {
1209                 struct acpi_device *child_adev = to_acpi_device_node(child);
1210
1211                 acpi_dev_for_each_child(adev, stop_on_next, &child_adev);
1212                 if (child_adev)
1213                         return acpi_fwnode_handle(child_adev);
1214
1215                 child = NULL;
1216         }
1217
1218         if (!child || is_acpi_data_node(child)) {
1219                 const struct acpi_data_node *data = to_acpi_data_node(fwnode);
1220                 const struct list_head *head;
1221                 struct list_head *next;
1222                 struct acpi_data_node *dn;
1223
1224                 /*
1225                  * We can have a combination of device and data nodes, e.g. with
1226                  * hierarchical _DSD properties. Make sure the adev pointer is
1227                  * restored before going through data nodes, otherwise we will
1228                  * be looking for data_nodes below the last device found instead
1229                  * of the common fwnode shared by device_nodes and data_nodes.
1230                  */
1231                 adev = to_acpi_device_node(fwnode);
1232                 if (adev)
1233                         head = &adev->data.subnodes;
1234                 else if (data)
1235                         head = &data->data.subnodes;
1236                 else
1237                         return NULL;
1238
1239                 if (list_empty(head))
1240                         return NULL;
1241
1242                 if (child) {
1243                         dn = to_acpi_data_node(child);
1244                         next = dn->sibling.next;
1245                         if (next == head)
1246                                 return NULL;
1247
1248                         dn = list_entry(next, struct acpi_data_node, sibling);
1249                 } else {
1250                         dn = list_first_entry(head, struct acpi_data_node, sibling);
1251                 }
1252                 return &dn->fwnode;
1253         }
1254         return NULL;
1255 }
1256
1257 /**
1258  * acpi_node_get_parent - Return parent fwnode of this fwnode
1259  * @fwnode: Firmware node whose parent to get
1260  *
1261  * Returns parent node of an ACPI device or data firmware node or %NULL if
1262  * not available.
1263  */
1264 static struct fwnode_handle *
1265 acpi_node_get_parent(const struct fwnode_handle *fwnode)
1266 {
1267         if (is_acpi_data_node(fwnode)) {
1268                 /* All data nodes have parent pointer so just return that */
1269                 return to_acpi_data_node(fwnode)->parent;
1270         }
1271         if (is_acpi_device_node(fwnode)) {
1272                 struct acpi_device *parent;
1273
1274                 parent = acpi_dev_parent(to_acpi_device_node(fwnode));
1275                 if (parent)
1276                         return acpi_fwnode_handle(parent);
1277         }
1278
1279         return NULL;
1280 }
1281
1282 /*
1283  * Return true if the node is an ACPI graph node. Called on either ports
1284  * or endpoints.
1285  */
1286 static bool is_acpi_graph_node(struct fwnode_handle *fwnode,
1287                                const char *str)
1288 {
1289         unsigned int len = strlen(str);
1290         const char *name;
1291
1292         if (!len || !is_acpi_data_node(fwnode))
1293                 return false;
1294
1295         name = to_acpi_data_node(fwnode)->name;
1296
1297         return (fwnode_property_present(fwnode, "reg") &&
1298                 !strncmp(name, str, len) && name[len] == '@') ||
1299                 fwnode_property_present(fwnode, str);
1300 }
1301
1302 /**
1303  * acpi_graph_get_next_endpoint - Get next endpoint ACPI firmware node
1304  * @fwnode: Pointer to the parent firmware node
1305  * @prev: Previous endpoint node or %NULL to get the first
1306  *
1307  * Looks up next endpoint ACPI firmware node below a given @fwnode. Returns
1308  * %NULL if there is no next endpoint or in case of error. In case of success
1309  * the next endpoint is returned.
1310  */
1311 static struct fwnode_handle *acpi_graph_get_next_endpoint(
1312         const struct fwnode_handle *fwnode, struct fwnode_handle *prev)
1313 {
1314         struct fwnode_handle *port = NULL;
1315         struct fwnode_handle *endpoint;
1316
1317         if (!prev) {
1318                 do {
1319                         port = fwnode_get_next_child_node(fwnode, port);
1320                         /*
1321                          * The names of the port nodes begin with "port@"
1322                          * followed by the number of the port node and they also
1323                          * have a "reg" property that also has the number of the
1324                          * port node. For compatibility reasons a node is also
1325                          * recognised as a port node from the "port" property.
1326                          */
1327                         if (is_acpi_graph_node(port, "port"))
1328                                 break;
1329                 } while (port);
1330         } else {
1331                 port = fwnode_get_parent(prev);
1332         }
1333
1334         if (!port)
1335                 return NULL;
1336
1337         endpoint = fwnode_get_next_child_node(port, prev);
1338         while (!endpoint) {
1339                 port = fwnode_get_next_child_node(fwnode, port);
1340                 if (!port)
1341                         break;
1342                 if (is_acpi_graph_node(port, "port"))
1343                         endpoint = fwnode_get_next_child_node(port, NULL);
1344         }
1345
1346         /*
1347          * The names of the endpoint nodes begin with "endpoint@" followed by
1348          * the number of the endpoint node and they also have a "reg" property
1349          * that also has the number of the endpoint node. For compatibility
1350          * reasons a node is also recognised as an endpoint node from the
1351          * "endpoint" property.
1352          */
1353         if (!is_acpi_graph_node(endpoint, "endpoint"))
1354                 return NULL;
1355
1356         return endpoint;
1357 }
1358
1359 /**
1360  * acpi_graph_get_child_prop_value - Return a child with a given property value
1361  * @fwnode: device fwnode
1362  * @prop_name: The name of the property to look for
1363  * @val: the desired property value
1364  *
1365  * Return the port node corresponding to a given port number. Returns
1366  * the child node on success, NULL otherwise.
1367  */
1368 static struct fwnode_handle *acpi_graph_get_child_prop_value(
1369         const struct fwnode_handle *fwnode, const char *prop_name,
1370         unsigned int val)
1371 {
1372         struct fwnode_handle *child;
1373
1374         fwnode_for_each_child_node(fwnode, child) {
1375                 u32 nr;
1376
1377                 if (fwnode_property_read_u32(child, prop_name, &nr))
1378                         continue;
1379
1380                 if (val == nr)
1381                         return child;
1382         }
1383
1384         return NULL;
1385 }
1386
1387
1388 /**
1389  * acpi_graph_get_remote_endpoint - Parses and returns remote end of an endpoint
1390  * @__fwnode: Endpoint firmware node pointing to a remote device
1391  *
1392  * Returns the remote endpoint corresponding to @__fwnode. NULL on error.
1393  */
1394 static struct fwnode_handle *
1395 acpi_graph_get_remote_endpoint(const struct fwnode_handle *__fwnode)
1396 {
1397         struct fwnode_handle *fwnode;
1398         unsigned int port_nr, endpoint_nr;
1399         struct fwnode_reference_args args;
1400         int ret;
1401
1402         memset(&args, 0, sizeof(args));
1403         ret = acpi_node_get_property_reference(__fwnode, "remote-endpoint", 0,
1404                                                &args);
1405         if (ret)
1406                 return NULL;
1407
1408         /* Direct endpoint reference? */
1409         if (!is_acpi_device_node(args.fwnode))
1410                 return args.nargs ? NULL : args.fwnode;
1411
1412         /*
1413          * Always require two arguments with the reference: port and
1414          * endpoint indices.
1415          */
1416         if (args.nargs != 2)
1417                 return NULL;
1418
1419         fwnode = args.fwnode;
1420         port_nr = args.args[0];
1421         endpoint_nr = args.args[1];
1422
1423         fwnode = acpi_graph_get_child_prop_value(fwnode, "port", port_nr);
1424
1425         return acpi_graph_get_child_prop_value(fwnode, "endpoint", endpoint_nr);
1426 }
1427
1428 static bool acpi_fwnode_device_is_available(const struct fwnode_handle *fwnode)
1429 {
1430         if (!is_acpi_device_node(fwnode))
1431                 return false;
1432
1433         return acpi_device_is_present(to_acpi_device_node(fwnode));
1434 }
1435
1436 static const void *
1437 acpi_fwnode_device_get_match_data(const struct fwnode_handle *fwnode,
1438                                   const struct device *dev)
1439 {
1440         return acpi_device_get_match_data(dev);
1441 }
1442
1443 static bool acpi_fwnode_device_dma_supported(const struct fwnode_handle *fwnode)
1444 {
1445         return acpi_dma_supported(to_acpi_device_node(fwnode));
1446 }
1447
1448 static enum dev_dma_attr
1449 acpi_fwnode_device_get_dma_attr(const struct fwnode_handle *fwnode)
1450 {
1451         return acpi_get_dma_attr(to_acpi_device_node(fwnode));
1452 }
1453
1454 static bool acpi_fwnode_property_present(const struct fwnode_handle *fwnode,
1455                                          const char *propname)
1456 {
1457         return !acpi_node_prop_get(fwnode, propname, NULL);
1458 }
1459
1460 static int
1461 acpi_fwnode_property_read_int_array(const struct fwnode_handle *fwnode,
1462                                     const char *propname,
1463                                     unsigned int elem_size, void *val,
1464                                     size_t nval)
1465 {
1466         enum dev_prop_type type;
1467
1468         switch (elem_size) {
1469         case sizeof(u8):
1470                 type = DEV_PROP_U8;
1471                 break;
1472         case sizeof(u16):
1473                 type = DEV_PROP_U16;
1474                 break;
1475         case sizeof(u32):
1476                 type = DEV_PROP_U32;
1477                 break;
1478         case sizeof(u64):
1479                 type = DEV_PROP_U64;
1480                 break;
1481         default:
1482                 return -ENXIO;
1483         }
1484
1485         return acpi_node_prop_read(fwnode, propname, type, val, nval);
1486 }
1487
1488 static int
1489 acpi_fwnode_property_read_string_array(const struct fwnode_handle *fwnode,
1490                                        const char *propname, const char **val,
1491                                        size_t nval)
1492 {
1493         return acpi_node_prop_read(fwnode, propname, DEV_PROP_STRING,
1494                                    val, nval);
1495 }
1496
1497 static int
1498 acpi_fwnode_get_reference_args(const struct fwnode_handle *fwnode,
1499                                const char *prop, const char *nargs_prop,
1500                                unsigned int args_count, unsigned int index,
1501                                struct fwnode_reference_args *args)
1502 {
1503         return __acpi_node_get_property_reference(fwnode, prop, index,
1504                                                   args_count, args);
1505 }
1506
1507 static const char *acpi_fwnode_get_name(const struct fwnode_handle *fwnode)
1508 {
1509         const struct acpi_device *adev;
1510         struct fwnode_handle *parent;
1511
1512         /* Is this the root node? */
1513         parent = fwnode_get_parent(fwnode);
1514         if (!parent)
1515                 return "\\";
1516
1517         fwnode_handle_put(parent);
1518
1519         if (is_acpi_data_node(fwnode)) {
1520                 const struct acpi_data_node *dn = to_acpi_data_node(fwnode);
1521
1522                 return dn->name;
1523         }
1524
1525         adev = to_acpi_device_node(fwnode);
1526         if (WARN_ON(!adev))
1527                 return NULL;
1528
1529         return acpi_device_bid(adev);
1530 }
1531
1532 static const char *
1533 acpi_fwnode_get_name_prefix(const struct fwnode_handle *fwnode)
1534 {
1535         struct fwnode_handle *parent;
1536
1537         /* Is this the root node? */
1538         parent = fwnode_get_parent(fwnode);
1539         if (!parent)
1540                 return "";
1541
1542         /* Is this 2nd node from the root? */
1543         parent = fwnode_get_next_parent(parent);
1544         if (!parent)
1545                 return "";
1546
1547         fwnode_handle_put(parent);
1548
1549         /* ACPI device or data node. */
1550         return ".";
1551 }
1552
1553 static struct fwnode_handle *
1554 acpi_fwnode_get_parent(struct fwnode_handle *fwnode)
1555 {
1556         return acpi_node_get_parent(fwnode);
1557 }
1558
1559 static int acpi_fwnode_graph_parse_endpoint(const struct fwnode_handle *fwnode,
1560                                             struct fwnode_endpoint *endpoint)
1561 {
1562         struct fwnode_handle *port_fwnode = fwnode_get_parent(fwnode);
1563
1564         endpoint->local_fwnode = fwnode;
1565
1566         if (fwnode_property_read_u32(port_fwnode, "reg", &endpoint->port))
1567                 fwnode_property_read_u32(port_fwnode, "port", &endpoint->port);
1568         if (fwnode_property_read_u32(fwnode, "reg", &endpoint->id))
1569                 fwnode_property_read_u32(fwnode, "endpoint", &endpoint->id);
1570
1571         return 0;
1572 }
1573
1574 static int acpi_fwnode_irq_get(const struct fwnode_handle *fwnode,
1575                                unsigned int index)
1576 {
1577         struct resource res;
1578         int ret;
1579
1580         ret = acpi_irq_get(ACPI_HANDLE_FWNODE(fwnode), index, &res);
1581         if (ret)
1582                 return ret;
1583
1584         return res.start;
1585 }
1586
1587 #define DECLARE_ACPI_FWNODE_OPS(ops) \
1588         const struct fwnode_operations ops = {                          \
1589                 .device_is_available = acpi_fwnode_device_is_available, \
1590                 .device_get_match_data = acpi_fwnode_device_get_match_data, \
1591                 .device_dma_supported =                         \
1592                         acpi_fwnode_device_dma_supported,               \
1593                 .device_get_dma_attr = acpi_fwnode_device_get_dma_attr, \
1594                 .property_present = acpi_fwnode_property_present,       \
1595                 .property_read_int_array =                              \
1596                         acpi_fwnode_property_read_int_array,            \
1597                 .property_read_string_array =                           \
1598                         acpi_fwnode_property_read_string_array,         \
1599                 .get_parent = acpi_node_get_parent,                     \
1600                 .get_next_child_node = acpi_get_next_subnode,           \
1601                 .get_named_child_node = acpi_fwnode_get_named_child_node, \
1602                 .get_name = acpi_fwnode_get_name,                       \
1603                 .get_name_prefix = acpi_fwnode_get_name_prefix,         \
1604                 .get_reference_args = acpi_fwnode_get_reference_args,   \
1605                 .graph_get_next_endpoint =                              \
1606                         acpi_graph_get_next_endpoint,                   \
1607                 .graph_get_remote_endpoint =                            \
1608                         acpi_graph_get_remote_endpoint,                 \
1609                 .graph_get_port_parent = acpi_fwnode_get_parent,        \
1610                 .graph_parse_endpoint = acpi_fwnode_graph_parse_endpoint, \
1611                 .irq_get = acpi_fwnode_irq_get,                         \
1612         };                                                              \
1613         EXPORT_SYMBOL_GPL(ops)
1614
1615 DECLARE_ACPI_FWNODE_OPS(acpi_device_fwnode_ops);
1616 DECLARE_ACPI_FWNODE_OPS(acpi_data_fwnode_ops);
1617 const struct fwnode_operations acpi_static_fwnode_ops;
1618
1619 bool is_acpi_device_node(const struct fwnode_handle *fwnode)
1620 {
1621         return !IS_ERR_OR_NULL(fwnode) &&
1622                 fwnode->ops == &acpi_device_fwnode_ops;
1623 }
1624 EXPORT_SYMBOL(is_acpi_device_node);
1625
1626 bool is_acpi_data_node(const struct fwnode_handle *fwnode)
1627 {
1628         return !IS_ERR_OR_NULL(fwnode) && fwnode->ops == &acpi_data_fwnode_ops;
1629 }
1630 EXPORT_SYMBOL(is_acpi_data_node);