drivers/acpi/namespace/nsxfeval.c

   1 /*******************************************************************************
   2  *
   3  * Module Name: nsxfeval - Public interfaces to the ACPI subsystem
   4  *                         ACPI Object evaluation interfaces
   5  *
   6  ******************************************************************************/
   7
   8 /*
   9  * Copyright (C) 2000 - 2008, Intel Corp.
  10  * All rights reserved.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions, and the following disclaimer,
  17  *    without modification.
  18  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  19  *    substantially similar to the "NO WARRANTY" disclaimer below
  20  *    ("Disclaimer") and any redistribution must be conditioned upon
  21  *    including a substantially similar Disclaimer requirement for further
  22  *    binary redistribution.
  23  * 3. Neither the names of the above-listed copyright holders nor the names
  24  *    of any contributors may be used to endorse or promote products derived
  25  *    from this software without specific prior written permission.
  26  *
  27  * Alternatively, this software may be distributed under the terms of the
  28  * GNU General Public License ("GPL") version 2 as published by the Free
  29  * Software Foundation.
  30  *
  31  * NO WARRANTY
  32  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  33  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  34  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  35  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  36  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  40  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  41  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  42  * POSSIBILITY OF SUCH DAMAGES.
  43  */
  44
  45 #include <acpi/acpi.h>
  46 #include <acpi/accommon.h>
  47 #include <acpi/acnamesp.h>
  48 #include <acpi/acinterp.h>
  49
  50 #define _COMPONENT          ACPI_NAMESPACE
  51 ACPI_MODULE_NAME("nsxfeval")
  52
  53 /* Local prototypes */
  54 static void acpi_ns_resolve_references(struct acpi_evaluate_info *info);
  55
  56 #ifdef ACPI_FUTURE_USAGE
  57 /*******************************************************************************
  58  *
  59  * FUNCTION:    acpi_evaluate_object_typed
  60  *
  61  * PARAMETERS:  Handle              - Object handle (optional)
  62  *              Pathname            - Object pathname (optional)
  63  *              external_params     - List of parameters to pass to method,
  64  *                                    terminated by NULL.  May be NULL
  65  *                                    if no parameters are being passed.
  66  *              return_buffer       - Where to put method's return value (if
  67  *                                    any).  If NULL, no value is returned.
  68  *              return_type         - Expected type of return object
  69  *
  70  * RETURN:      Status
  71  *
  72  * DESCRIPTION: Find and evaluate the given object, passing the given
  73  *              parameters if necessary.  One of "Handle" or "Pathname" must
  74  *              be valid (non-null)
  75  *
  76  ******************************************************************************/
  77
  78 acpi_status
  79 acpi_evaluate_object_typed(acpi_handle handle,
  80                            acpi_string pathname,
  81                            struct acpi_object_list *external_params,
  82                            struct acpi_buffer *return_buffer,
  83                            acpi_object_type return_type)
  84 {
  85         acpi_status status;
  86         u8 must_free = FALSE;
  87
  88         ACPI_FUNCTION_TRACE(acpi_evaluate_object_typed);
  89
  90         /* Return buffer must be valid */
  91
  92         if (!return_buffer) {
  93                 return_ACPI_STATUS(AE_BAD_PARAMETER);
  94         }
  95
  96         if (return_buffer->length == ACPI_ALLOCATE_BUFFER) {
  97                 must_free = TRUE;
  98         }
  99
 100         /* Evaluate the object */
 101
 102         status =
 103             acpi_evaluate_object(handle, pathname, external_params,
 104                                  return_buffer);
 105         if (ACPI_FAILURE(status)) {
 106                 return_ACPI_STATUS(status);
 107         }
 108
 109         /* Type ANY means "don't care" */
 110
 111         if (return_type == ACPI_TYPE_ANY) {
 112                 return_ACPI_STATUS(AE_OK);
 113         }
 114
 115         if (return_buffer->length == 0) {
 116
 117                 /* Error because caller specifically asked for a return value */
 118
 119                 ACPI_ERROR((AE_INFO, "No return value"));
 120                 return_ACPI_STATUS(AE_NULL_OBJECT);
 121         }
 122
 123         /* Examine the object type returned from evaluate_object */
 124
 125         if (((union acpi_object *)return_buffer->pointer)->type == return_type) {
 126                 return_ACPI_STATUS(AE_OK);
 127         }
 128
 129         /* Return object type does not match requested type */
 130
 131         ACPI_ERROR((AE_INFO,
 132                     "Incorrect return type [%s] requested [%s]",
 133                     acpi_ut_get_type_name(((union acpi_object *)return_buffer->
 134                                            pointer)->type),
 135                     acpi_ut_get_type_name(return_type)));
 136
 137         if (must_free) {
 138
 139                 /* Caller used ACPI_ALLOCATE_BUFFER, free the return buffer */
 140
 141                 ACPI_FREE(return_buffer->pointer);
 142                 return_buffer->pointer = NULL;
 143         }
 144
 145         return_buffer->length = 0;
 146         return_ACPI_STATUS(AE_TYPE);
 147 }
 148
 149 ACPI_EXPORT_SYMBOL(acpi_evaluate_object_typed)
 150 #endif                          /*  ACPI_FUTURE_USAGE  */
 151 /*******************************************************************************
 152  *
 153  * FUNCTION:    acpi_evaluate_object
 154  *
 155  * PARAMETERS:  Handle              - Object handle (optional)
 156  *              Pathname            - Object pathname (optional)
 157  *              external_params     - List of parameters to pass to method,
 158  *                                    terminated by NULL.  May be NULL
 159  *                                    if no parameters are being passed.
 160  *              return_buffer       - Where to put method's return value (if
 161  *                                    any).  If NULL, no value is returned.
 162  *
 163  * RETURN:      Status
 164  *
 165  * DESCRIPTION: Find and evaluate the given object, passing the given
 166  *              parameters if necessary.  One of "Handle" or "Pathname" must
 167  *              be valid (non-null)
 168  *
 169  ******************************************************************************/
 170 acpi_status
 171 acpi_evaluate_object(acpi_handle handle,
 172                      acpi_string pathname,
 173                      struct acpi_object_list *external_params,
 174                      struct acpi_buffer *return_buffer)
 175 {
 176         acpi_status status;
 177         struct acpi_evaluate_info *info;
 178         acpi_size buffer_space_needed;
 179         u32 i;
 180
 181         ACPI_FUNCTION_TRACE(acpi_evaluate_object);
 182
 183         /* Allocate and initialize the evaluation information block */
 184
 185         info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
 186         if (!info) {
 187                 return_ACPI_STATUS(AE_NO_MEMORY);
 188         }
 189
 190         info->pathname = pathname;
 191
 192         /* Convert and validate the device handle */
 193
 194         info->prefix_node = acpi_ns_map_handle_to_node(handle);
 195         if (!info->prefix_node) {
 196                 status = AE_BAD_PARAMETER;
 197                 goto cleanup;
 198         }
 199
 200         /*
 201          * If there are parameters to be passed to a control method, the external
 202          * objects must all be converted to internal objects
 203          */
 204         if (external_params && external_params->count) {
 205                 /*
 206                  * Allocate a new parameter block for the internal objects
 207                  * Add 1 to count to allow for null terminated internal list
 208                  */
 209                 info->parameters = ACPI_ALLOCATE_ZEROED(((acpi_size)
 210                                                          external_params->
 211                                                          count +
 212                                                          1) * sizeof(void *));
 213                 if (!info->parameters) {
 214                         status = AE_NO_MEMORY;
 215                         goto cleanup;
 216                 }
 217
 218                 /* Convert each external object in the list to an internal object */
 219
 220                 for (i = 0; i < external_params->count; i++) {
 221                         status =
 222                             acpi_ut_copy_eobject_to_iobject(&external_params->
 223                                                             pointer[i],
 224                                                             &info->
 225                                                             parameters[i]);
 226                         if (ACPI_FAILURE(status)) {
 227                                 goto cleanup;
 228                         }
 229                 }
 230                 info->parameters[external_params->count] = NULL;
 231         }
 232
 233         /*
 234          * Three major cases:
 235          * 1) Fully qualified pathname
 236          * 2) No handle, not fully qualified pathname (error)
 237          * 3) Valid handle
 238          */
 239         if ((pathname) && (acpi_ns_valid_root_prefix(pathname[0]))) {
 240
 241                 /* The path is fully qualified, just evaluate by name */
 242
 243                 info->prefix_node = NULL;
 244                 status = acpi_ns_evaluate(info);
 245         } else if (!handle) {
 246                 /*
 247                  * A handle is optional iff a fully qualified pathname is specified.
 248                  * Since we've already handled fully qualified names above, this is
 249                  * an error
 250                  */
 251                 if (!pathname) {
 252                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 253                                           "Both Handle and Pathname are NULL"));
 254                 } else {
 255                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 256                                           "Null Handle with relative pathname [%s]",
 257                                           pathname));
 258                 }
 259
 260                 status = AE_BAD_PARAMETER;
 261         } else {
 262                 /* We have a namespace a node and a possible relative path */
 263
 264                 status = acpi_ns_evaluate(info);
 265         }
 266
 267         /*
 268          * If we are expecting a return value, and all went well above,
 269          * copy the return value to an external object.
 270          */
 271         if (return_buffer) {
 272                 if (!info->return_object) {
 273                         return_buffer->length = 0;
 274                 } else {
 275                         if (ACPI_GET_DESCRIPTOR_TYPE(info->return_object) ==
 276                             ACPI_DESC_TYPE_NAMED) {
 277                                 /*
 278                                  * If we received a NS Node as a return object, this means that
 279                                  * the object we are evaluating has nothing interesting to
 280                                  * return (such as a mutex, etc.)  We return an error because
 281                                  * these types are essentially unsupported by this interface.
 282                                  * We don't check up front because this makes it easier to add
 283                                  * support for various types at a later date if necessary.
 284                                  */
 285                                 status = AE_TYPE;
 286                                 info->return_object = NULL;     /* No need to delete a NS Node */
 287                                 return_buffer->length = 0;
 288                         }
 289
 290                         if (ACPI_SUCCESS(status)) {
 291
 292                                 /* Dereference Index and ref_of references */
 293
 294                                 acpi_ns_resolve_references(info);
 295
 296                                 /* Get the size of the returned object */
 297
 298                                 status =
 299                                     acpi_ut_get_object_size(info->return_object,
 300                                                             &buffer_space_needed);
 301                                 if (ACPI_SUCCESS(status)) {
 302
 303                                         /* Validate/Allocate/Clear caller buffer */
 304
 305                                         status =
 306                                             acpi_ut_initialize_buffer
 307                                             (return_buffer,
 308                                              buffer_space_needed);
 309                                         if (ACPI_FAILURE(status)) {
 310                                                 /*
 311                                                  * Caller's buffer is too small or a new one can't
 312                                                  * be allocated
 313                                                  */
 314                                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 315                                                                   "Needed buffer size %X, %s\n",
 316                                                                   (u32)
 317                                                                   buffer_space_needed,
 318                                                                   acpi_format_exception
 319                                                                   (status)));
 320                                         } else {
 321                                                 /* We have enough space for the object, build it */
 322
 323                                                 status =
 324                                                     acpi_ut_copy_iobject_to_eobject
 325                                                     (info->return_object,
 326                                                      return_buffer);
 327                                         }
 328                                 }
 329                         }
 330                 }
 331         }
 332
 333         if (info->return_object) {
 334                 /*
 335                  * Delete the internal return object. NOTE: Interpreter must be
 336                  * locked to avoid race condition.
 337                  */
 338                 acpi_ex_enter_interpreter();
 339
 340                 /* Remove one reference on the return object (should delete it) */
 341
 342                 acpi_ut_remove_reference(info->return_object);
 343                 acpi_ex_exit_interpreter();
 344         }
 345
 346       cleanup:
 347
 348         /* Free the input parameter list (if we created one) */
 349
 350         if (info->parameters) {
 351
 352                 /* Free the allocated parameter block */
 353
 354                 acpi_ut_delete_internal_object_list(info->parameters);
 355         }
 356
 357         ACPI_FREE(info);
 358         return_ACPI_STATUS(status);
 359 }
 360
 361 ACPI_EXPORT_SYMBOL(acpi_evaluate_object)
 362
 363 /*******************************************************************************
 364  *
 365  * FUNCTION:    acpi_ns_resolve_references
 366  *
 367  * PARAMETERS:  Info                    - Evaluation info block
 368  *
 369  * RETURN:      Info->return_object is replaced with the dereferenced object
 370  *
 371  * DESCRIPTION: Dereference certain reference objects. Called before an
 372  *              internal return object is converted to an external union acpi_object.
 373  *
 374  * Performs an automatic dereference of Index and ref_of reference objects.
 375  * These reference objects are not supported by the union acpi_object, so this is a
 376  * last resort effort to return something useful. Also, provides compatibility
 377  * with other ACPI implementations.
 378  *
 379  * NOTE: does not handle references within returned package objects or nested
 380  * references, but this support could be added later if found to be necessary.
 381  *
 382  ******************************************************************************/
 383 static void acpi_ns_resolve_references(struct acpi_evaluate_info *info)
 384 {
 385         union acpi_operand_object *obj_desc = NULL;
 386         struct acpi_namespace_node *node;
 387
 388         /* We are interested in reference objects only */
 389
 390         if (ACPI_GET_OBJECT_TYPE(info->return_object) !=
 391             ACPI_TYPE_LOCAL_REFERENCE) {
 392                 return;
 393         }
 394
 395         /*
 396          * Two types of references are supported - those created by Index and
 397          * ref_of operators. A name reference (AML_NAMEPATH_OP) can be converted
 398          * to an union acpi_object, so it is not dereferenced here. A ddb_handle
 399          * (AML_LOAD_OP) cannot be dereferenced, nor can it be converted to
 400          * an union acpi_object.
 401          */
 402         switch (info->return_object->reference.class) {
 403         case ACPI_REFCLASS_INDEX:
 404
 405                 obj_desc = *(info->return_object->reference.where);
 406                 break;
 407
 408         case ACPI_REFCLASS_REFOF:
 409
 410                 node = info->return_object->reference.object;
 411                 if (node) {
 412                         obj_desc = node->object;
 413                 }
 414                 break;
 415
 416         default:
 417                 return;
 418         }
 419
 420         /* Replace the existing reference object */
 421
 422         if (obj_desc) {
 423                 acpi_ut_add_reference(obj_desc);
 424                 acpi_ut_remove_reference(info->return_object);
 425                 info->return_object = obj_desc;
 426         }
 427
 428         return;
 429 }
 430
 431 /*******************************************************************************
 432  *
 433  * FUNCTION:    acpi_walk_namespace
 434  *
 435  * PARAMETERS:  Type                - acpi_object_type to search for
 436  *              start_object        - Handle in namespace where search begins
 437  *              max_depth           - Depth to which search is to reach
 438  *              user_function       - Called when an object of "Type" is found
 439  *              Context             - Passed to user function
 440  *              return_value        - Location where return value of
 441  *                                    user_function is put if terminated early
 442  *
 443  * RETURNS      Return value from the user_function if terminated early.
 444  *              Otherwise, returns NULL.
 445  *
 446  * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
 447  *              starting (and ending) at the object specified by start_handle.
 448  *              The user_function is called whenever an object that matches
 449  *              the type parameter is found.  If the user function returns
 450  *              a non-zero value, the search is terminated immediately and this
 451  *              value is returned to the caller.
 452  *
 453  *              The point of this procedure is to provide a generic namespace
 454  *              walk routine that can be called from multiple places to
 455  *              provide multiple services;  the User Function can be tailored
 456  *              to each task, whether it is a print function, a compare
 457  *              function, etc.
 458  *
 459  ******************************************************************************/
 460
 461 acpi_status
 462 acpi_walk_namespace(acpi_object_type type,
 463                     acpi_handle start_object,
 464                     u32 max_depth,
 465                     acpi_walk_callback user_function,
 466                     void *context, void **return_value)
 467 {
 468         acpi_status status;
 469
 470         ACPI_FUNCTION_TRACE(acpi_walk_namespace);
 471
 472         /* Parameter validation */
 473
 474         if ((type > ACPI_TYPE_LOCAL_MAX) || (!max_depth) || (!user_function)) {
 475                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 476         }
 477
 478         /*
 479          * Lock the namespace around the walk.
 480          * The namespace will be unlocked/locked around each call
 481          * to the user function - since this function
 482          * must be allowed to make Acpi calls itself.
 483          */
 484         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 485         if (ACPI_FAILURE(status)) {
 486                 return_ACPI_STATUS(status);
 487         }
 488
 489         status = acpi_ns_walk_namespace(type, start_object, max_depth,
 490                                         ACPI_NS_WALK_UNLOCK,
 491                                         user_function, context, return_value);
 492
 493         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 494         return_ACPI_STATUS(status);
 495 }
 496
 497 ACPI_EXPORT_SYMBOL(acpi_walk_namespace)
 498
 499 /*******************************************************************************
 500  *
 501  * FUNCTION:    acpi_ns_get_device_callback
 502  *
 503  * PARAMETERS:  Callback from acpi_get_device
 504  *
 505  * RETURN:      Status
 506  *
 507  * DESCRIPTION: Takes callbacks from walk_namespace and filters out all non-
 508  *              present devices, or if they specified a HID, it filters based
 509  *              on that.
 510  *
 511  ******************************************************************************/
 512 static acpi_status
 513 acpi_ns_get_device_callback(acpi_handle obj_handle,
 514                             u32 nesting_level,
 515                             void *context, void **return_value)
 516 {
 517         struct acpi_get_devices_info *info = context;
 518         acpi_status status;
 519         struct acpi_namespace_node *node;
 520         u32 flags;
 521         struct acpica_device_id hid;
 522         struct acpi_compatible_id_list *cid;
 523         u32 i;
 524         int found;
 525
 526         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 527         if (ACPI_FAILURE(status)) {
 528                 return (status);
 529         }
 530
 531         node = acpi_ns_map_handle_to_node(obj_handle);
 532         status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 533         if (ACPI_FAILURE(status)) {
 534                 return (status);
 535         }
 536
 537         if (!node) {
 538                 return (AE_BAD_PARAMETER);
 539         }
 540
 541         /* Run _STA to determine if device is present */
 542
 543         status = acpi_ut_execute_STA(node, &flags);
 544         if (ACPI_FAILURE(status)) {
 545                 return (AE_CTRL_DEPTH);
 546         }
 547
 548         if (!(flags & ACPI_STA_DEVICE_PRESENT) &&
 549             !(flags & ACPI_STA_DEVICE_FUNCTIONING)) {
 550                 /*
 551                  * Don't examine the children of the device only when the
 552                  * device is neither present nor functional. See ACPI spec,
 553                  * description of _STA for more information.
 554                  */
 555                 return (AE_CTRL_DEPTH);
 556         }
 557
 558         /* Filter based on device HID & CID */
 559
 560         if (info->hid != NULL) {
 561                 status = acpi_ut_execute_HID(node, &hid);
 562                 if (status == AE_NOT_FOUND) {
 563                         return (AE_OK);
 564                 } else if (ACPI_FAILURE(status)) {
 565                         return (AE_CTRL_DEPTH);
 566                 }
 567
 568                 if (ACPI_STRNCMP(hid.value, info->hid, sizeof(hid.value)) != 0) {
 569
 570                         /* Get the list of Compatible IDs */
 571
 572                         status = acpi_ut_execute_CID(node, &cid);
 573                         if (status == AE_NOT_FOUND) {
 574                                 return (AE_OK);
 575                         } else if (ACPI_FAILURE(status)) {
 576                                 return (AE_CTRL_DEPTH);
 577                         }
 578
 579                         /* Walk the CID list */
 580
 581                         found = 0;
 582                         for (i = 0; i < cid->count; i++) {
 583                                 if (ACPI_STRNCMP(cid->id[i].value, info->hid,
 584                                                  sizeof(struct
 585                                                         acpi_compatible_id)) ==
 586                                     0) {
 587                                         found = 1;
 588                                         break;
 589                                 }
 590                         }
 591                         ACPI_FREE(cid);
 592                         if (!found)
 593                                 return (AE_OK);
 594                 }
 595         }
 596
 597         status = info->user_function(obj_handle, nesting_level, info->context,
 598                                      return_value);
 599         return (status);
 600 }
 601
 602 /*******************************************************************************
 603  *
 604  * FUNCTION:    acpi_get_devices
 605  *
 606  * PARAMETERS:  HID                 - HID to search for. Can be NULL.
 607  *              user_function       - Called when a matching object is found
 608  *              Context             - Passed to user function
 609  *              return_value        - Location where return value of
 610  *                                    user_function is put if terminated early
 611  *
 612  * RETURNS      Return value from the user_function if terminated early.
 613  *              Otherwise, returns NULL.
 614  *
 615  * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
 616  *              starting (and ending) at the object specified by start_handle.
 617  *              The user_function is called whenever an object of type
 618  *              Device is found.  If the user function returns
 619  *              a non-zero value, the search is terminated immediately and this
 620  *              value is returned to the caller.
 621  *
 622  *              This is a wrapper for walk_namespace, but the callback performs
 623  *              additional filtering. Please see acpi_ns_get_device_callback.
 624  *
 625  ******************************************************************************/
 626
 627 acpi_status
 628 acpi_get_devices(const char *HID,
 629                  acpi_walk_callback user_function,
 630                  void *context, void **return_value)
 631 {
 632         acpi_status status;
 633         struct acpi_get_devices_info info;
 634
 635         ACPI_FUNCTION_TRACE(acpi_get_devices);
 636
 637         /* Parameter validation */
 638
 639         if (!user_function) {
 640                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 641         }
 642
 643         /*
 644          * We're going to call their callback from OUR callback, so we need
 645          * to know what it is, and their context parameter.
 646          */
 647         info.hid = HID;
 648         info.context = context;
 649         info.user_function = user_function;
 650
 651         /*
 652          * Lock the namespace around the walk.
 653          * The namespace will be unlocked/locked around each call
 654          * to the user function - since this function
 655          * must be allowed to make Acpi calls itself.
 656          */
 657         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 658         if (ACPI_FAILURE(status)) {
 659                 return_ACPI_STATUS(status);
 660         }
 661
 662         status = acpi_ns_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
 663                                         ACPI_UINT32_MAX, ACPI_NS_WALK_UNLOCK,
 664                                         acpi_ns_get_device_callback, &info,
 665                                         return_value);
 666
 667         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 668         return_ACPI_STATUS(status);
 669 }
 670
 671 ACPI_EXPORT_SYMBOL(acpi_get_devices)
 672
 673 /*******************************************************************************
 674  *
 675  * FUNCTION:    acpi_attach_data
 676  *
 677  * PARAMETERS:  obj_handle          - Namespace node
 678  *              Handler             - Handler for this attachment
 679  *              Data                - Pointer to data to be attached
 680  *
 681  * RETURN:      Status
 682  *
 683  * DESCRIPTION: Attach arbitrary data and handler to a namespace node.
 684  *
 685  ******************************************************************************/
 686 acpi_status
 687 acpi_attach_data(acpi_handle obj_handle,
 688                  acpi_object_handler handler, void *data)
 689 {
 690         struct acpi_namespace_node *node;
 691         acpi_status status;
 692
 693         /* Parameter validation */
 694
 695         if (!obj_handle || !handler || !data) {
 696                 return (AE_BAD_PARAMETER);
 697         }
 698
 699         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 700         if (ACPI_FAILURE(status)) {
 701                 return (status);
 702         }
 703
 704         /* Convert and validate the handle */
 705
 706         node = acpi_ns_map_handle_to_node(obj_handle);
 707         if (!node) {
 708                 status = AE_BAD_PARAMETER;
 709                 goto unlock_and_exit;
 710         }
 711
 712         status = acpi_ns_attach_data(node, handler, data);
 713
 714       unlock_and_exit:
 715         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 716         return (status);
 717 }
 718
 719 ACPI_EXPORT_SYMBOL(acpi_attach_data)
 720
 721 /*******************************************************************************
 722  *
 723  * FUNCTION:    acpi_detach_data
 724  *
 725  * PARAMETERS:  obj_handle          - Namespace node handle
 726  *              Handler             - Handler used in call to acpi_attach_data
 727  *
 728  * RETURN:      Status
 729  *
 730  * DESCRIPTION: Remove data that was previously attached to a node.
 731  *
 732  ******************************************************************************/
 733 acpi_status
 734 acpi_detach_data(acpi_handle obj_handle, acpi_object_handler handler)
 735 {
 736         struct acpi_namespace_node *node;
 737         acpi_status status;
 738
 739         /* Parameter validation */
 740
 741         if (!obj_handle || !handler) {
 742                 return (AE_BAD_PARAMETER);
 743         }
 744
 745         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 746         if (ACPI_FAILURE(status)) {
 747                 return (status);
 748         }
 749
 750         /* Convert and validate the handle */
 751
 752         node = acpi_ns_map_handle_to_node(obj_handle);
 753         if (!node) {
 754                 status = AE_BAD_PARAMETER;
 755                 goto unlock_and_exit;
 756         }
 757
 758         status = acpi_ns_detach_data(node, handler);
 759
 760       unlock_and_exit:
 761         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 762         return (status);
 763 }
 764
 765 ACPI_EXPORT_SYMBOL(acpi_detach_data)
 766
 767 /*******************************************************************************
 768  *
 769  * FUNCTION:    acpi_get_data
 770  *
 771  * PARAMETERS:  obj_handle          - Namespace node
 772  *              Handler             - Handler used in call to attach_data
 773  *              Data                - Where the data is returned
 774  *
 775  * RETURN:      Status
 776  *
 777  * DESCRIPTION: Retrieve data that was previously attached to a namespace node.
 778  *
 779  ******************************************************************************/
 780 acpi_status
 781 acpi_get_data(acpi_handle obj_handle, acpi_object_handler handler, void **data)
 782 {
 783         struct acpi_namespace_node *node;
 784         acpi_status status;
 785
 786         /* Parameter validation */
 787
 788         if (!obj_handle || !handler || !data) {
 789                 return (AE_BAD_PARAMETER);
 790         }
 791
 792         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 793         if (ACPI_FAILURE(status)) {
 794                 return (status);
 795         }
 796
 797         /* Convert and validate the handle */
 798
 799         node = acpi_ns_map_handle_to_node(obj_handle);
 800         if (!node) {
 801                 status = AE_BAD_PARAMETER;
 802                 goto unlock_and_exit;
 803         }
 804
 805         status = acpi_ns_get_attached_data(node, handler, data);
 806
 807       unlock_and_exit:
 808         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 809         return (status);
 810 }
 811
 812 ACPI_EXPORT_SYMBOL(acpi_get_data)