drivers/acpi/property.c

   1 /*
   2  * ACPI device specific properties support.
   3  *
   4  * Copyright (C) 2014, Intel Corporation
   5  * All rights reserved.
   6  *
   7  * Authors: Mika Westerberg <mika.westerberg@linux.intel.com>
   8  *          Darren Hart <dvhart@linux.intel.com>
   9  *          Rafael J. Wysocki <rafael.j.wysocki@intel.com>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License version 2 as
  13  * published by the Free Software Foundation.
  14  */
  15
  16 #include <linux/acpi.h>
  17 #include <linux/device.h>
  18 #include <linux/export.h>
  19
  20 #include "internal.h"
  21
  22 static int acpi_data_get_property_array(const struct acpi_device_data *data,
  23                                         const char *name,
  24                                         acpi_object_type type,
  25                                         const union acpi_object **obj);
  26
  27 /* ACPI _DSD device properties GUID: daffd814-6eba-4d8c-8a91-bc9bbf4aa301 */
  28 static const guid_t prp_guid =
  29         GUID_INIT(0xdaffd814, 0x6eba, 0x4d8c,
  30                   0x8a, 0x91, 0xbc, 0x9b, 0xbf, 0x4a, 0xa3, 0x01);
  31 /* ACPI _DSD data subnodes GUID: dbb8e3e6-5886-4ba6-8795-1319f52a966b */
  32 static const guid_t ads_guid =
  33         GUID_INIT(0xdbb8e3e6, 0x5886, 0x4ba6,
  34                   0x87, 0x95, 0x13, 0x19, 0xf5, 0x2a, 0x96, 0x6b);
  35
  36 static bool acpi_enumerate_nondev_subnodes(acpi_handle scope,
  37                                            const union acpi_object *desc,
  38                                            struct acpi_device_data *data,
  39                                            struct fwnode_handle *parent);
  40 static bool acpi_extract_properties(const union acpi_object *desc,
  41                                     struct acpi_device_data *data);
  42
  43 static bool acpi_nondev_subnode_extract(const union acpi_object *desc,
  44                                         acpi_handle handle,
  45                                         const union acpi_object *link,
  46                                         struct list_head *list,
  47                                         struct fwnode_handle *parent)
  48 {
  49         struct acpi_data_node *dn;
  50         bool result;
  51
  52         dn = kzalloc(sizeof(*dn), GFP_KERNEL);
  53         if (!dn)
  54                 return false;
  55
  56         dn->name = link->package.elements[0].string.pointer;
  57         dn->fwnode.ops = &acpi_data_fwnode_ops;
  58         dn->parent = parent;
  59         INIT_LIST_HEAD(&dn->data.subnodes);
  60
  61         result = acpi_extract_properties(desc, &dn->data);
  62
  63         if (handle) {
  64                 acpi_handle scope;
  65                 acpi_status status;
  66
  67                 /*
  68                  * The scope for the subnode object lookup is the one of the
  69                  * namespace node (device) containing the object that has
  70                  * returned the package.  That is, it's the scope of that
  71                  * object's parent.
  72                  */
  73                 status = acpi_get_parent(handle, &scope);
  74                 if (ACPI_SUCCESS(status)
  75                     && acpi_enumerate_nondev_subnodes(scope, desc, &dn->data,
  76                                                       &dn->fwnode))
  77                         result = true;
  78         } else if (acpi_enumerate_nondev_subnodes(NULL, desc, &dn->data,
  79                                                   &dn->fwnode)) {
  80                 result = true;
  81         }
  82
  83         if (result) {
  84                 dn->handle = handle;
  85                 dn->data.pointer = desc;
  86                 list_add_tail(&dn->sibling, list);
  87                 return true;
  88         }
  89
  90         kfree(dn);
  91         acpi_handle_debug(handle, "Invalid properties/subnodes data, skipping\n");
  92         return false;
  93 }
  94
  95 static bool acpi_nondev_subnode_data_ok(acpi_handle handle,
  96                                         const union acpi_object *link,
  97                                         struct list_head *list,
  98                                         struct fwnode_handle *parent)
  99 {
 100         struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
 101         acpi_status status;
 102
 103         status = acpi_evaluate_object_typed(handle, NULL, NULL, &buf,
 104                                             ACPI_TYPE_PACKAGE);
 105         if (ACPI_FAILURE(status))
 106                 return false;
 107
 108         if (acpi_nondev_subnode_extract(buf.pointer, handle, link, list,
 109                                         parent))
 110                 return true;
 111
 112         ACPI_FREE(buf.pointer);
 113         return false;
 114 }
 115
 116 static bool acpi_nondev_subnode_ok(acpi_handle scope,
 117                                    const union acpi_object *link,
 118                                    struct list_head *list,
 119                                    struct fwnode_handle *parent)
 120 {
 121         acpi_handle handle;
 122         acpi_status status;
 123
 124         if (!scope)
 125                 return false;
 126
 127         status = acpi_get_handle(scope, link->package.elements[1].string.pointer,
 128                                  &handle);
 129         if (ACPI_FAILURE(status))
 130                 return false;
 131
 132         return acpi_nondev_subnode_data_ok(handle, link, list, parent);
 133 }
 134
 135 static int acpi_add_nondev_subnodes(acpi_handle scope,
 136                                     const union acpi_object *links,
 137                                     struct list_head *list,
 138                                     struct fwnode_handle *parent)
 139 {
 140         bool ret = false;
 141         int i;
 142
 143         for (i = 0; i < links->package.count; i++) {
 144                 const union acpi_object *link, *desc;
 145                 acpi_handle handle;
 146                 bool result;
 147
 148                 link = &links->package.elements[i];
 149                 /* Only two elements allowed. */
 150                 if (link->package.count != 2)
 151                         continue;
 152
 153                 /* The first one must be a string. */
 154                 if (link->package.elements[0].type != ACPI_TYPE_STRING)
 155                         continue;
 156
 157                 /* The second one may be a string, a reference or a package. */
 158                 switch (link->package.elements[1].type) {
 159                 case ACPI_TYPE_STRING:
 160                         result = acpi_nondev_subnode_ok(scope, link, list,
 161                                                          parent);
 162                         break;
 163                 case ACPI_TYPE_LOCAL_REFERENCE:
 164                         handle = link->package.elements[1].reference.handle;
 165                         result = acpi_nondev_subnode_data_ok(handle, link, list,
 166                                                              parent);
 167                         break;
 168                 case ACPI_TYPE_PACKAGE:
 169                         desc = &link->package.elements[1];
 170                         result = acpi_nondev_subnode_extract(desc, NULL, link,
 171                                                              list, parent);
 172                         break;
 173                 default:
 174                         result = false;
 175                         break;
 176                 }
 177                 ret = ret || result;
 178         }
 179
 180         return ret;
 181 }
 182
 183 static bool acpi_enumerate_nondev_subnodes(acpi_handle scope,
 184                                            const union acpi_object *desc,
 185                                            struct acpi_device_data *data,
 186                                            struct fwnode_handle *parent)
 187 {
 188         int i;
 189
 190         /* Look for the ACPI data subnodes GUID. */
 191         for (i = 0; i < desc->package.count; i += 2) {
 192                 const union acpi_object *guid, *links;
 193
 194                 guid = &desc->package.elements[i];
 195                 links = &desc->package.elements[i + 1];
 196
 197                 /*
 198                  * The first element must be a GUID and the second one must be
 199                  * a package.
 200                  */
 201                 if (guid->type != ACPI_TYPE_BUFFER ||
 202                     guid->buffer.length != 16 ||
 203                     links->type != ACPI_TYPE_PACKAGE)
 204                         break;
 205
 206                 if (!guid_equal((guid_t *)guid->buffer.pointer, &ads_guid))
 207                         continue;
 208
 209                 return acpi_add_nondev_subnodes(scope, links, &data->subnodes,
 210                                                 parent);
 211         }
 212
 213         return false;
 214 }
 215
 216 static bool acpi_property_value_ok(const union acpi_object *value)
 217 {
 218         int j;
 219
 220         /*
 221          * The value must be an integer, a string, a reference, or a package
 222          * whose every element must be an integer, a string, or a reference.
 223          */
 224         switch (value->type) {
 225         case ACPI_TYPE_INTEGER:
 226         case ACPI_TYPE_STRING:
 227         case ACPI_TYPE_LOCAL_REFERENCE:
 228                 return true;
 229
 230         case ACPI_TYPE_PACKAGE:
 231                 for (j = 0; j < value->package.count; j++)
 232                         switch (value->package.elements[j].type) {
 233                         case ACPI_TYPE_INTEGER:
 234                         case ACPI_TYPE_STRING:
 235                         case ACPI_TYPE_LOCAL_REFERENCE:
 236                                 continue;
 237
 238                         default:
 239                                 return false;
 240                         }
 241
 242                 return true;
 243         }
 244         return false;
 245 }
 246
 247 static bool acpi_properties_format_valid(const union acpi_object *properties)
 248 {
 249         int i;
 250
 251         for (i = 0; i < properties->package.count; i++) {
 252                 const union acpi_object *property;
 253
 254                 property = &properties->package.elements[i];
 255                 /*
 256                  * Only two elements allowed, the first one must be a string and
 257                  * the second one has to satisfy certain conditions.
 258                  */
 259                 if (property->package.count != 2
 260                     || property->package.elements[0].type != ACPI_TYPE_STRING
 261                     || !acpi_property_value_ok(&property->package.elements[1]))
 262                         return false;
 263         }
 264         return true;
 265 }
 266
 267 static void acpi_init_of_compatible(struct acpi_device *adev)
 268 {
 269         const union acpi_object *of_compatible;
 270         int ret;
 271
 272         ret = acpi_data_get_property_array(&adev->data, "compatible",
 273                                            ACPI_TYPE_STRING, &of_compatible);
 274         if (ret) {
 275                 ret = acpi_dev_get_property(adev, "compatible",
 276                                             ACPI_TYPE_STRING, &of_compatible);
 277                 if (ret) {
 278                         if (adev->parent
 279                             && adev->parent->flags.of_compatible_ok)
 280                                 goto out;
 281
 282                         return;
 283                 }
 284         }
 285         adev->data.of_compatible = of_compatible;
 286
 287  out:
 288         adev->flags.of_compatible_ok = 1;
 289 }
 290
 291 static bool acpi_extract_properties(const union acpi_object *desc,
 292                                     struct acpi_device_data *data)
 293 {
 294         int i;
 295
 296         if (desc->package.count % 2)
 297                 return false;
 298
 299         /* Look for the device properties GUID. */
 300         for (i = 0; i < desc->package.count; i += 2) {
 301                 const union acpi_object *guid, *properties;
 302
 303                 guid = &desc->package.elements[i];
 304                 properties = &desc->package.elements[i + 1];
 305
 306                 /*
 307                  * The first element must be a GUID and the second one must be
 308                  * a package.
 309                  */
 310                 if (guid->type != ACPI_TYPE_BUFFER ||
 311                     guid->buffer.length != 16 ||
 312                     properties->type != ACPI_TYPE_PACKAGE)
 313                         break;
 314
 315                 if (!guid_equal((guid_t *)guid->buffer.pointer, &prp_guid))
 316                         continue;
 317
 318                 /*
 319                  * We found the matching GUID. Now validate the format of the
 320                  * package immediately following it.
 321                  */
 322                 if (!acpi_properties_format_valid(properties))
 323                         break;
 324
 325                 data->properties = properties;
 326                 return true;
 327         }
 328
 329         return false;
 330 }
 331
 332 void acpi_init_properties(struct acpi_device *adev)
 333 {
 334         struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
 335         struct acpi_hardware_id *hwid;
 336         acpi_status status;
 337         bool acpi_of = false;
 338
 339         INIT_LIST_HEAD(&adev->data.subnodes);
 340
 341         if (!adev->handle)
 342                 return;
 343
 344         /*
 345          * Check if ACPI_DT_NAMESPACE_HID is present and inthat case we fill in
 346          * Device Tree compatible properties for this device.
 347          */
 348         list_for_each_entry(hwid, &adev->pnp.ids, list) {
 349                 if (!strcmp(hwid->id, ACPI_DT_NAMESPACE_HID)) {
 350                         acpi_of = true;
 351                         break;
 352                 }
 353         }
 354
 355         status = acpi_evaluate_object_typed(adev->handle, "_DSD", NULL, &buf,
 356                                             ACPI_TYPE_PACKAGE);
 357         if (ACPI_FAILURE(status))
 358                 goto out;
 359
 360         if (acpi_extract_properties(buf.pointer, &adev->data)) {
 361                 adev->data.pointer = buf.pointer;
 362                 if (acpi_of)
 363                         acpi_init_of_compatible(adev);
 364         }
 365         if (acpi_enumerate_nondev_subnodes(adev->handle, buf.pointer,
 366                                         &adev->data, acpi_fwnode_handle(adev)))
 367                 adev->data.pointer = buf.pointer;
 368
 369         if (!adev->data.pointer) {
 370                 acpi_handle_debug(adev->handle, "Invalid _DSD data, skipping\n");
 371                 ACPI_FREE(buf.pointer);
 372         }
 373
 374  out:
 375         if (acpi_of && !adev->flags.of_compatible_ok)
 376                 acpi_handle_info(adev->handle,
 377                          ACPI_DT_NAMESPACE_HID " requires 'compatible' property\n");
 378
 379         if (!adev->data.pointer)
 380                 acpi_extract_apple_properties(adev);
 381 }
 382
 383 static void acpi_destroy_nondev_subnodes(struct list_head *list)
 384 {
 385         struct acpi_data_node *dn, *next;
 386
 387         if (list_empty(list))
 388                 return;
 389
 390         list_for_each_entry_safe_reverse(dn, next, list, sibling) {
 391                 acpi_destroy_nondev_subnodes(&dn->data.subnodes);
 392                 wait_for_completion(&dn->kobj_done);
 393                 list_del(&dn->sibling);
 394                 ACPI_FREE((void *)dn->data.pointer);
 395                 kfree(dn);
 396         }
 397 }
 398
 399 void acpi_free_properties(struct acpi_device *adev)
 400 {
 401         acpi_destroy_nondev_subnodes(&adev->data.subnodes);
 402         ACPI_FREE((void *)adev->data.pointer);
 403         adev->data.of_compatible = NULL;
 404         adev->data.pointer = NULL;
 405         adev->data.properties = NULL;
 406 }
 407
 408 /**
 409  * acpi_data_get_property - return an ACPI property with given name
 410  * @data: ACPI device deta object to get the property from
 411  * @name: Name of the property
 412  * @type: Expected property type
 413  * @obj: Location to store the property value (if not %NULL)
 414  *
 415  * Look up a property with @name and store a pointer to the resulting ACPI
 416  * object at the location pointed to by @obj if found.
 417  *
 418  * Callers must not attempt to free the returned objects.  These objects will be
 419  * freed by the ACPI core automatically during the removal of @data.
 420  *
 421  * Return: %0 if property with @name has been found (success),
 422  *         %-EINVAL if the arguments are invalid,
 423  *         %-EINVAL if the property doesn't exist,
 424  *         %-EPROTO if the property value type doesn't match @type.
 425  */
 426 static int acpi_data_get_property(const struct acpi_device_data *data,
 427                                   const char *name, acpi_object_type type,
 428                                   const union acpi_object **obj)
 429 {
 430         const union acpi_object *properties;
 431         int i;
 432
 433         if (!data || !name)
 434                 return -EINVAL;
 435
 436         if (!data->pointer || !data->properties)
 437                 return -EINVAL;
 438
 439         properties = data->properties;
 440         for (i = 0; i < properties->package.count; i++) {
 441                 const union acpi_object *propname, *propvalue;
 442                 const union acpi_object *property;
 443
 444                 property = &properties->package.elements[i];
 445
 446                 propname = &property->package.elements[0];
 447                 propvalue = &property->package.elements[1];
 448
 449                 if (!strcmp(name, propname->string.pointer)) {
 450                         if (type != ACPI_TYPE_ANY && propvalue->type != type)
 451                                 return -EPROTO;
 452                         if (obj)
 453                                 *obj = propvalue;
 454
 455                         return 0;
 456                 }
 457         }
 458         return -EINVAL;
 459 }
 460
 461 /**
 462  * acpi_dev_get_property - return an ACPI property with given name.
 463  * @adev: ACPI device to get the property from.
 464  * @name: Name of the property.
 465  * @type: Expected property type.
 466  * @obj: Location to store the property value (if not %NULL).
 467  */
 468 int acpi_dev_get_property(const struct acpi_device *adev, const char *name,
 469                           acpi_object_type type, const union acpi_object **obj)
 470 {
 471         return adev ? acpi_data_get_property(&adev->data, name, type, obj) : -EINVAL;
 472 }
 473 EXPORT_SYMBOL_GPL(acpi_dev_get_property);
 474
 475 static const struct acpi_device_data *
 476 acpi_device_data_of_node(const struct fwnode_handle *fwnode)
 477 {
 478         if (is_acpi_device_node(fwnode)) {
 479                 const struct acpi_device *adev = to_acpi_device_node(fwnode);
 480                 return &adev->data;
 481         } else if (is_acpi_data_node(fwnode)) {
 482                 const struct acpi_data_node *dn = to_acpi_data_node(fwnode);
 483                 return &dn->data;
 484         }
 485         return NULL;
 486 }
 487
 488 /**
 489  * acpi_node_prop_get - return an ACPI property with given name.
 490  * @fwnode: Firmware node to get the property from.
 491  * @propname: Name of the property.
 492  * @valptr: Location to store a pointer to the property value (if not %NULL).
 493  */
 494 int acpi_node_prop_get(const struct fwnode_handle *fwnode,
 495                        const char *propname, void **valptr)
 496 {
 497         return acpi_data_get_property(acpi_device_data_of_node(fwnode),
 498                                       propname, ACPI_TYPE_ANY,
 499                                       (const union acpi_object **)valptr);
 500 }
 501
 502 /**
 503  * acpi_data_get_property_array - return an ACPI array property with given name
 504  * @adev: ACPI data object to get the property from
 505  * @name: Name of the property
 506  * @type: Expected type of array elements
 507  * @obj: Location to store a pointer to the property value (if not NULL)
 508  *
 509  * Look up an array property with @name and store a pointer to the resulting
 510  * ACPI object at the location pointed to by @obj if found.
 511  *
 512  * Callers must not attempt to free the returned objects.  Those objects will be
 513  * freed by the ACPI core automatically during the removal of @data.
 514  *
 515  * Return: %0 if array property (package) with @name has been found (success),
 516  *         %-EINVAL if the arguments are invalid,
 517  *         %-EINVAL if the property doesn't exist,
 518  *         %-EPROTO if the property is not a package or the type of its elements
 519  *           doesn't match @type.
 520  */
 521 static int acpi_data_get_property_array(const struct acpi_device_data *data,
 522                                         const char *name,
 523                                         acpi_object_type type,
 524                                         const union acpi_object **obj)
 525 {
 526         const union acpi_object *prop;
 527         int ret, i;
 528
 529         ret = acpi_data_get_property(data, name, ACPI_TYPE_PACKAGE, &prop);
 530         if (ret)
 531                 return ret;
 532
 533         if (type != ACPI_TYPE_ANY) {
 534                 /* Check that all elements are of correct type. */
 535                 for (i = 0; i < prop->package.count; i++)
 536                         if (prop->package.elements[i].type != type)
 537                                 return -EPROTO;
 538         }
 539         if (obj)
 540                 *obj = prop;
 541
 542         return 0;
 543 }
 544
 545 /**
 546  * __acpi_node_get_property_reference - returns handle to the referenced object
 547  * @fwnode: Firmware node to get the property from
 548  * @propname: Name of the property
 549  * @index: Index of the reference to return
 550  * @num_args: Maximum number of arguments after each reference
 551  * @args: Location to store the returned reference with optional arguments
 552  *
 553  * Find property with @name, verifify that it is a package containing at least
 554  * one object reference and if so, store the ACPI device object pointer to the
 555  * target object in @args->adev.  If the reference includes arguments, store
 556  * them in the @args->args[] array.
 557  *
 558  * If there's more than one reference in the property value package, @index is
 559  * used to select the one to return.
 560  *
 561  * It is possible to leave holes in the property value set like in the
 562  * example below:
 563  *
 564  * Package () {
 565  *     "cs-gpios",
 566  *     Package () {
 567  *        ^GPIO, 19, 0, 0,
 568  *        ^GPIO, 20, 0, 0,
 569  *        0,
 570  *        ^GPIO, 21, 0, 0,
 571  *     }
 572  * }
 573  *
 574  * Calling this function with index %2 return %-ENOENT and with index %3
 575  * returns the last entry. If the property does not contain any more values
 576  * %-ENODATA is returned. The NULL entry must be single integer and
 577  * preferably contain value %0.
 578  *
 579  * Return: %0 on success, negative error code on failure.
 580  */
 581 int __acpi_node_get_property_reference(const struct fwnode_handle *fwnode,
 582         const char *propname, size_t index, size_t num_args,
 583         struct acpi_reference_args *args)
 584 {
 585         const union acpi_object *element, *end;
 586         const union acpi_object *obj;
 587         const struct acpi_device_data *data;
 588         struct acpi_device *device;
 589         int ret, idx = 0;
 590
 591         data = acpi_device_data_of_node(fwnode);
 592         if (!data)
 593                 return -EINVAL;
 594
 595         ret = acpi_data_get_property(data, propname, ACPI_TYPE_ANY, &obj);
 596         if (ret)
 597                 return ret;
 598
 599         /*
 600          * The simplest case is when the value is a single reference.  Just
 601          * return that reference then.
 602          */
 603         if (obj->type == ACPI_TYPE_LOCAL_REFERENCE) {
 604                 if (index)
 605                         return -EINVAL;
 606
 607                 ret = acpi_bus_get_device(obj->reference.handle, &device);
 608                 if (ret)
 609                         return ret;
 610
 611                 args->adev = device;
 612                 args->nargs = 0;
 613                 return 0;
 614         }
 615
 616         /*
 617          * If it is not a single reference, then it is a package of
 618          * references followed by number of ints as follows:
 619          *
 620          *  Package () { REF, INT, REF, INT, INT }
 621          *
 622          * The index argument is then used to determine which reference
 623          * the caller wants (along with the arguments).
 624          */
 625         if (obj->type != ACPI_TYPE_PACKAGE || index >= obj->package.count)
 626                 return -EPROTO;
 627
 628         element = obj->package.elements;
 629         end = element + obj->package.count;
 630
 631         while (element < end) {
 632                 u32 nargs, i;
 633
 634                 if (element->type == ACPI_TYPE_LOCAL_REFERENCE) {
 635                         ret = acpi_bus_get_device(element->reference.handle,
 636                                                   &device);
 637                         if (ret)
 638                                 return -ENODEV;
 639
 640                         nargs = 0;
 641                         element++;
 642
 643                         /* assume following integer elements are all args */
 644                         for (i = 0; element + i < end && i < num_args; i++) {
 645                                 int type = element[i].type;
 646
 647                                 if (type == ACPI_TYPE_INTEGER)
 648                                         nargs++;
 649                                 else if (type == ACPI_TYPE_LOCAL_REFERENCE)
 650                                         break;
 651                                 else
 652                                         return -EPROTO;
 653                         }
 654
 655                         if (nargs > MAX_ACPI_REFERENCE_ARGS)
 656                                 return -EPROTO;
 657
 658                         if (idx == index) {
 659                                 args->adev = device;
 660                                 args->nargs = nargs;
 661                                 for (i = 0; i < nargs; i++)
 662                                         args->args[i] = element[i].integer.value;
 663
 664                                 return 0;
 665                         }
 666
 667                         element += nargs;
 668                 } else if (element->type == ACPI_TYPE_INTEGER) {
 669                         if (idx == index)
 670                                 return -ENOENT;
 671                         element++;
 672                 } else {
 673                         return -EPROTO;
 674                 }
 675
 676                 idx++;
 677         }
 678
 679         return -ENODATA;
 680 }
 681 EXPORT_SYMBOL_GPL(__acpi_node_get_property_reference);
 682
 683 static int acpi_data_prop_read_single(const struct acpi_device_data *data,
 684                                       const char *propname,
 685                                       enum dev_prop_type proptype, void *val)
 686 {
 687         const union acpi_object *obj;
 688         int ret;
 689
 690         if (!val)
 691                 return -EINVAL;
 692
 693         if (proptype >= DEV_PROP_U8 && proptype <= DEV_PROP_U64) {
 694                 ret = acpi_data_get_property(data, propname, ACPI_TYPE_INTEGER, &obj);
 695                 if (ret)
 696                         return ret;
 697
 698                 switch (proptype) {
 699                 case DEV_PROP_U8:
 700                         if (obj->integer.value > U8_MAX)
 701                                 return -EOVERFLOW;
 702                         *(u8 *)val = obj->integer.value;
 703                         break;
 704                 case DEV_PROP_U16:
 705                         if (obj->integer.value > U16_MAX)
 706                                 return -EOVERFLOW;
 707                         *(u16 *)val = obj->integer.value;
 708                         break;
 709                 case DEV_PROP_U32:
 710                         if (obj->integer.value > U32_MAX)
 711                                 return -EOVERFLOW;
 712                         *(u32 *)val = obj->integer.value;
 713                         break;
 714                 default:
 715                         *(u64 *)val = obj->integer.value;
 716                         break;
 717                 }
 718         } else if (proptype == DEV_PROP_STRING) {
 719                 ret = acpi_data_get_property(data, propname, ACPI_TYPE_STRING, &obj);
 720                 if (ret)
 721                         return ret;
 722
 723                 *(char **)val = obj->string.pointer;
 724
 725                 return 1;
 726         } else {
 727                 ret = -EINVAL;
 728         }
 729         return ret;
 730 }
 731
 732 int acpi_dev_prop_read_single(struct acpi_device *adev, const char *propname,
 733                               enum dev_prop_type proptype, void *val)
 734 {
 735         int ret;
 736
 737         if (!adev)
 738                 return -EINVAL;
 739
 740         ret = acpi_data_prop_read_single(&adev->data, propname, proptype, val);
 741         if (ret < 0 || proptype != ACPI_TYPE_STRING)
 742                 return ret;
 743         return 0;
 744 }
 745
 746 static int acpi_copy_property_array_u8(const union acpi_object *items, u8 *val,
 747                                        size_t nval)
 748 {
 749         int i;
 750
 751         for (i = 0; i < nval; i++) {
 752                 if (items[i].type != ACPI_TYPE_INTEGER)
 753                         return -EPROTO;
 754                 if (items[i].integer.value > U8_MAX)
 755                         return -EOVERFLOW;
 756
 757                 val[i] = items[i].integer.value;
 758         }
 759         return 0;
 760 }
 761
 762 static int acpi_copy_property_array_u16(const union acpi_object *items,
 763                                         u16 *val, size_t nval)
 764 {
 765         int i;
 766
 767         for (i = 0; i < nval; i++) {
 768                 if (items[i].type != ACPI_TYPE_INTEGER)
 769                         return -EPROTO;
 770                 if (items[i].integer.value > U16_MAX)
 771                         return -EOVERFLOW;
 772
 773                 val[i] = items[i].integer.value;
 774         }
 775         return 0;
 776 }
 777
 778 static int acpi_copy_property_array_u32(const union acpi_object *items,
 779                                         u32 *val, size_t nval)
 780 {
 781         int i;
 782
 783         for (i = 0; i < nval; i++) {
 784                 if (items[i].type != ACPI_TYPE_INTEGER)
 785                         return -EPROTO;
 786                 if (items[i].integer.value > U32_MAX)
 787                         return -EOVERFLOW;
 788
 789                 val[i] = items[i].integer.value;
 790         }
 791         return 0;
 792 }
 793
 794 static int acpi_copy_property_array_u64(const union acpi_object *items,
 795                                         u64 *val, size_t nval)
 796 {
 797         int i;
 798
 799         for (i = 0; i < nval; i++) {
 800                 if (items[i].type != ACPI_TYPE_INTEGER)
 801                         return -EPROTO;
 802
 803                 val[i] = items[i].integer.value;
 804         }
 805         return 0;
 806 }
 807
 808 static int acpi_copy_property_array_string(const union acpi_object *items,
 809                                            char **val, size_t nval)
 810 {
 811         int i;
 812
 813         for (i = 0; i < nval; i++) {
 814                 if (items[i].type != ACPI_TYPE_STRING)
 815                         return -EPROTO;
 816
 817                 val[i] = items[i].string.pointer;
 818         }
 819         return nval;
 820 }
 821
 822 static int acpi_data_prop_read(const struct acpi_device_data *data,
 823                                const char *propname,
 824                                enum dev_prop_type proptype,
 825                                void *val, size_t nval)
 826 {
 827         const union acpi_object *obj;
 828         const union acpi_object *items;
 829         int ret;
 830
 831         if (val && nval == 1) {
 832                 ret = acpi_data_prop_read_single(data, propname, proptype, val);
 833                 if (ret >= 0)
 834                         return ret;
 835         }
 836
 837         ret = acpi_data_get_property_array(data, propname, ACPI_TYPE_ANY, &obj);
 838         if (ret)
 839                 return ret;
 840
 841         if (!val)
 842                 return obj->package.count;
 843
 844         if (proptype != DEV_PROP_STRING && nval > obj->package.count)
 845                 return -EOVERFLOW;
 846         else if (nval <= 0)
 847                 return -EINVAL;
 848
 849         items = obj->package.elements;
 850
 851         switch (proptype) {
 852         case DEV_PROP_U8:
 853                 ret = acpi_copy_property_array_u8(items, (u8 *)val, nval);
 854                 break;
 855         case DEV_PROP_U16:
 856                 ret = acpi_copy_property_array_u16(items, (u16 *)val, nval);
 857                 break;
 858         case DEV_PROP_U32:
 859                 ret = acpi_copy_property_array_u32(items, (u32 *)val, nval);
 860                 break;
 861         case DEV_PROP_U64:
 862                 ret = acpi_copy_property_array_u64(items, (u64 *)val, nval);
 863                 break;
 864         case DEV_PROP_STRING:
 865                 ret = acpi_copy_property_array_string(
 866                         items, (char **)val,
 867                         min_t(u32, nval, obj->package.count));
 868                 break;
 869         default:
 870                 ret = -EINVAL;
 871                 break;
 872         }
 873         return ret;
 874 }
 875
 876 int acpi_dev_prop_read(const struct acpi_device *adev, const char *propname,
 877                        enum dev_prop_type proptype, void *val, size_t nval)
 878 {
 879         return adev ? acpi_data_prop_read(&adev->data, propname, proptype, val, nval) : -EINVAL;
 880 }
 881
 882 /**
 883  * acpi_node_prop_read - retrieve the value of an ACPI property with given name.
 884  * @fwnode: Firmware node to get the property from.
 885  * @propname: Name of the property.
 886  * @proptype: Expected property type.
 887  * @val: Location to store the property value (if not %NULL).
 888  * @nval: Size of the array pointed to by @val.
 889  *
 890  * If @val is %NULL, return the number of array elements comprising the value
 891  * of the property.  Otherwise, read at most @nval values to the array at the
 892  * location pointed to by @val.
 893  */
 894 int acpi_node_prop_read(const struct fwnode_handle *fwnode,
 895                         const char *propname, enum dev_prop_type proptype,
 896                         void *val, size_t nval)
 897 {
 898         return acpi_data_prop_read(acpi_device_data_of_node(fwnode),
 899                                    propname, proptype, val, nval);
 900 }
 901
 902 /**
 903  * acpi_get_next_subnode - Return the next child node handle for a fwnode
 904  * @fwnode: Firmware node to find the next child node for.
 905  * @child: Handle to one of the device's child nodes or a null handle.
 906  */
 907 struct fwnode_handle *acpi_get_next_subnode(const struct fwnode_handle *fwnode,
 908                                             struct fwnode_handle *child)
 909 {
 910         const struct acpi_device *adev = to_acpi_device_node(fwnode);
 911         struct acpi_device *child_adev = NULL;
 912         const struct list_head *head;
 913         struct list_head *next;
 914
 915         if (!child || is_acpi_device_node(child)) {
 916                 if (adev)
 917                         head = &adev->children;
 918                 else
 919                         goto nondev;
 920
 921                 if (list_empty(head))
 922                         goto nondev;
 923
 924                 if (child) {
 925                         child_adev = to_acpi_device_node(child);
 926                         next = child_adev->node.next;
 927                         if (next == head) {
 928                                 child = NULL;
 929                                 goto nondev;
 930                         }
 931                         child_adev = list_entry(next, struct acpi_device, node);
 932                 } else {
 933                         child_adev = list_first_entry(head, struct acpi_device,
 934                                                       node);
 935                 }
 936                 return acpi_fwnode_handle(child_adev);
 937         }
 938
 939  nondev:
 940         if (!child || is_acpi_data_node(child)) {
 941                 const struct acpi_data_node *data = to_acpi_data_node(fwnode);
 942                 struct acpi_data_node *dn;
 943
 944                 if (child_adev)
 945                         head = &child_adev->data.subnodes;
 946                 else if (data)
 947                         head = &data->data.subnodes;
 948                 else
 949                         return NULL;
 950
 951                 if (list_empty(head))
 952                         return NULL;
 953
 954                 if (child) {
 955                         dn = to_acpi_data_node(child);
 956                         next = dn->sibling.next;
 957                         if (next == head)
 958                                 return NULL;
 959
 960                         dn = list_entry(next, struct acpi_data_node, sibling);
 961                 } else {
 962                         dn = list_first_entry(head, struct acpi_data_node, sibling);
 963                 }
 964                 return &dn->fwnode;
 965         }
 966         return NULL;
 967 }
 968
 969 /**
 970  * acpi_node_get_parent - Return parent fwnode of this fwnode
 971  * @fwnode: Firmware node whose parent to get
 972  *
 973  * Returns parent node of an ACPI device or data firmware node or %NULL if
 974  * not available.
 975  */
 976 struct fwnode_handle *acpi_node_get_parent(const struct fwnode_handle *fwnode)
 977 {
 978         if (is_acpi_data_node(fwnode)) {
 979                 /* All data nodes have parent pointer so just return that */
 980                 return to_acpi_data_node(fwnode)->parent;
 981         } else if (is_acpi_device_node(fwnode)) {
 982                 acpi_handle handle, parent_handle;
 983
 984                 handle = to_acpi_device_node(fwnode)->handle;
 985                 if (ACPI_SUCCESS(acpi_get_parent(handle, &parent_handle))) {
 986                         struct acpi_device *adev;
 987
 988                         if (!acpi_bus_get_device(parent_handle, &adev))
 989                                 return acpi_fwnode_handle(adev);
 990                 }
 991         }
 992
 993         return NULL;
 994 }
 995
 996 /**
 997  * acpi_graph_get_next_endpoint - Get next endpoint ACPI firmware node
 998  * @fwnode: Pointer to the parent firmware node
 999  * @prev: Previous endpoint node or %NULL to get the first
1000  *
1001  * Looks up next endpoint ACPI firmware node below a given @fwnode. Returns
1002  * %NULL if there is no next endpoint, ERR_PTR() in case of error. In case
1003  * of success the next endpoint is returned.
1004  */
1005 struct fwnode_handle *acpi_graph_get_next_endpoint(
1006         const struct fwnode_handle *fwnode, struct fwnode_handle *prev)
1007 {
1008         struct fwnode_handle *port = NULL;
1009         struct fwnode_handle *endpoint;
1010
1011         if (!prev) {
1012                 do {
1013                         port = fwnode_get_next_child_node(fwnode, port);
1014                         /* Ports must have port property */
1015                         if (fwnode_property_present(port, "port"))
1016                                 break;
1017                 } while (port);
1018         } else {
1019                 port = fwnode_get_parent(prev);
1020         }
1021
1022         if (!port)
1023                 return NULL;
1024
1025         endpoint = fwnode_get_next_child_node(port, prev);
1026         while (!endpoint) {
1027                 port = fwnode_get_next_child_node(fwnode, port);
1028                 if (!port)
1029                         break;
1030                 if (fwnode_property_present(port, "port"))
1031                         endpoint = fwnode_get_next_child_node(port, NULL);
1032         }
1033
1034         if (endpoint) {
1035                 /* Endpoints must have "endpoint" property */
1036                 if (!fwnode_property_present(endpoint, "endpoint"))
1037                         return ERR_PTR(-EPROTO);
1038         }
1039
1040         return endpoint;
1041 }
1042
1043 /**
1044  * acpi_graph_get_child_prop_value - Return a child with a given property value
1045  * @fwnode: device fwnode
1046  * @prop_name: The name of the property to look for
1047  * @val: the desired property value
1048  *
1049  * Return the port node corresponding to a given port number. Returns
1050  * the child node on success, NULL otherwise.
1051  */
1052 static struct fwnode_handle *acpi_graph_get_child_prop_value(
1053         const struct fwnode_handle *fwnode, const char *prop_name,
1054         unsigned int val)
1055 {
1056         struct fwnode_handle *child;
1057
1058         fwnode_for_each_child_node(fwnode, child) {
1059                 u32 nr;
1060
1061                 if (fwnode_property_read_u32(child, prop_name, &nr))
1062                         continue;
1063
1064                 if (val == nr)
1065                         return child;
1066         }
1067
1068         return NULL;
1069 }
1070
1071
1072 /**
1073  * acpi_graph_get_remote_enpoint - Parses and returns remote end of an endpoint
1074  * @fwnode: Endpoint firmware node pointing to a remote device
1075  * @parent: Firmware node of remote port parent is filled here if not %NULL
1076  * @port: Firmware node of remote port is filled here if not %NULL
1077  * @endpoint: Firmware node of remote endpoint is filled here if not %NULL
1078  *
1079  * Function parses remote end of ACPI firmware remote endpoint and fills in
1080  * fields requested by the caller. Returns %0 in case of success and
1081  * negative errno otherwise.
1082  */
1083 int acpi_graph_get_remote_endpoint(const struct fwnode_handle *__fwnode,
1084                                    struct fwnode_handle **parent,
1085                                    struct fwnode_handle **port,
1086                                    struct fwnode_handle **endpoint)
1087 {
1088         struct fwnode_handle *fwnode;
1089         unsigned int port_nr, endpoint_nr;
1090         struct acpi_reference_args args;
1091         int ret;
1092
1093         memset(&args, 0, sizeof(args));
1094         ret = acpi_node_get_property_reference(__fwnode, "remote-endpoint", 0,
1095                                                &args);
1096         if (ret)
1097                 return ret;
1098
1099         /*
1100          * Always require two arguments with the reference: port and
1101          * endpoint indices.
1102          */
1103         if (args.nargs != 2)
1104                 return -EPROTO;
1105
1106         fwnode = acpi_fwnode_handle(args.adev);
1107         port_nr = args.args[0];
1108         endpoint_nr = args.args[1];
1109
1110         if (parent)
1111                 *parent = fwnode;
1112
1113         if (!port && !endpoint)
1114                 return 0;
1115
1116         fwnode = acpi_graph_get_child_prop_value(fwnode, "port", port_nr);
1117         if (!fwnode)
1118                 return -EPROTO;
1119
1120         if (port)
1121                 *port = fwnode;
1122
1123         if (!endpoint)
1124                 return 0;
1125
1126         fwnode = acpi_graph_get_child_prop_value(fwnode, "endpoint",
1127                                                  endpoint_nr);
1128         if (!fwnode)
1129                 return -EPROTO;
1130
1131         *endpoint = fwnode;
1132
1133         return 0;
1134 }
1135
1136 static bool acpi_fwnode_device_is_available(const struct fwnode_handle *fwnode)
1137 {
1138         if (!is_acpi_device_node(fwnode))
1139                 return false;
1140
1141         return acpi_device_is_present(to_acpi_device_node(fwnode));
1142 }
1143
1144 static bool acpi_fwnode_property_present(const struct fwnode_handle *fwnode,
1145                                          const char *propname)
1146 {
1147         return !acpi_node_prop_get(fwnode, propname, NULL);
1148 }
1149
1150 static int
1151 acpi_fwnode_property_read_int_array(const struct fwnode_handle *fwnode,
1152                                     const char *propname,
1153                                     unsigned int elem_size, void *val,
1154                                     size_t nval)
1155 {
1156         enum dev_prop_type type;
1157
1158         switch (elem_size) {
1159         case sizeof(u8):
1160                 type = DEV_PROP_U8;
1161                 break;
1162         case sizeof(u16):
1163                 type = DEV_PROP_U16;
1164                 break;
1165         case sizeof(u32):
1166                 type = DEV_PROP_U32;
1167                 break;
1168         case sizeof(u64):
1169                 type = DEV_PROP_U64;
1170                 break;
1171         default:
1172                 return -ENXIO;
1173         }
1174
1175         return acpi_node_prop_read(fwnode, propname, type, val, nval);
1176 }
1177
1178 static int
1179 acpi_fwnode_property_read_string_array(const struct fwnode_handle *fwnode,
1180                                        const char *propname, const char **val,
1181                                        size_t nval)
1182 {
1183         return acpi_node_prop_read(fwnode, propname, DEV_PROP_STRING,
1184                                    val, nval);
1185 }
1186
1187 static struct fwnode_handle *
1188 acpi_fwnode_get_named_child_node(const struct fwnode_handle *fwnode,
1189                                  const char *childname)
1190 {
1191         struct fwnode_handle *child;
1192
1193         /*
1194          * Find first matching named child node of this fwnode.
1195          * For ACPI this will be a data only sub-node.
1196          */
1197         fwnode_for_each_child_node(fwnode, child)
1198                 if (acpi_data_node_match(child, childname))
1199                         return child;
1200
1201         return NULL;
1202 }
1203
1204 static int
1205 acpi_fwnode_get_reference_args(const struct fwnode_handle *fwnode,
1206                                const char *prop, const char *nargs_prop,
1207                                unsigned int args_count, unsigned int index,
1208                                struct fwnode_reference_args *args)
1209 {
1210         struct acpi_reference_args acpi_args;
1211         unsigned int i;
1212         int ret;
1213
1214         ret = __acpi_node_get_property_reference(fwnode, prop, index,
1215                                                  args_count, &acpi_args);
1216         if (ret < 0)
1217                 return ret;
1218         if (!args)
1219                 return 0;
1220
1221         args->nargs = acpi_args.nargs;
1222         args->fwnode = acpi_fwnode_handle(acpi_args.adev);
1223
1224         for (i = 0; i < NR_FWNODE_REFERENCE_ARGS; i++)
1225                 args->args[i] = i < acpi_args.nargs ? acpi_args.args[i] : 0;
1226
1227         return 0;
1228 }
1229
1230 static struct fwnode_handle *
1231 acpi_fwnode_graph_get_next_endpoint(const struct fwnode_handle *fwnode,
1232                                     struct fwnode_handle *prev)
1233 {
1234         struct fwnode_handle *endpoint;
1235
1236         endpoint = acpi_graph_get_next_endpoint(fwnode, prev);
1237         if (IS_ERR(endpoint))
1238                 return NULL;
1239
1240         return endpoint;
1241 }
1242
1243 static struct fwnode_handle *
1244 acpi_fwnode_graph_get_remote_endpoint(const struct fwnode_handle *fwnode)
1245 {
1246         struct fwnode_handle *endpoint = NULL;
1247
1248         acpi_graph_get_remote_endpoint(fwnode, NULL, NULL, &endpoint);
1249
1250         return endpoint;
1251 }
1252
1253 static struct fwnode_handle *
1254 acpi_fwnode_get_parent(struct fwnode_handle *fwnode)
1255 {
1256         return acpi_node_get_parent(fwnode);
1257 }
1258
1259 static int acpi_fwnode_graph_parse_endpoint(const struct fwnode_handle *fwnode,
1260                                             struct fwnode_endpoint *endpoint)
1261 {
1262         struct fwnode_handle *port_fwnode = fwnode_get_parent(fwnode);
1263
1264         endpoint->local_fwnode = fwnode;
1265
1266         fwnode_property_read_u32(port_fwnode, "port", &endpoint->port);
1267         fwnode_property_read_u32(fwnode, "endpoint", &endpoint->id);
1268
1269         return 0;
1270 }
1271
1272 #define DECLARE_ACPI_FWNODE_OPS(ops) \
1273         const struct fwnode_operations ops = {                          \
1274                 .device_is_available = acpi_fwnode_device_is_available, \
1275                 .property_present = acpi_fwnode_property_present,       \
1276                 .property_read_int_array =                              \
1277                         acpi_fwnode_property_read_int_array,            \
1278                 .property_read_string_array =                           \
1279                         acpi_fwnode_property_read_string_array,         \
1280                 .get_parent = acpi_node_get_parent,                     \
1281                 .get_next_child_node = acpi_get_next_subnode,           \
1282                 .get_named_child_node = acpi_fwnode_get_named_child_node, \
1283                 .get_reference_args = acpi_fwnode_get_reference_args,   \
1284                 .graph_get_next_endpoint =                              \
1285                         acpi_fwnode_graph_get_next_endpoint,            \
1286                 .graph_get_remote_endpoint =                            \
1287                         acpi_fwnode_graph_get_remote_endpoint,          \
1288                 .graph_get_port_parent = acpi_fwnode_get_parent,        \
1289                 .graph_parse_endpoint = acpi_fwnode_graph_parse_endpoint, \
1290         };                                                              \
1291         EXPORT_SYMBOL_GPL(ops)
1292
1293 DECLARE_ACPI_FWNODE_OPS(acpi_device_fwnode_ops);
1294 DECLARE_ACPI_FWNODE_OPS(acpi_data_fwnode_ops);
1295 const struct fwnode_operations acpi_static_fwnode_ops;