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 - 2006, R. Byron Moore
  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/acnamesp.h>
  47 #include <acpi/acinterp.h>
  48
  49 #define _COMPONENT          ACPI_NAMESPACE
  50 ACPI_MODULE_NAME("nsxfeval")
  51
  52 #ifdef ACPI_FUTURE_USAGE
  53 /*******************************************************************************
  54  *
  55  * FUNCTION:    acpi_evaluate_object_typed
  56  *
  57  * PARAMETERS:  Handle              - Object handle (optional)
  58  *              Pathname            - Object pathname (optional)
  59  *              external_params     - List of parameters to pass to method,
  60  *                                    terminated by NULL.  May be NULL
  61  *                                    if no parameters are being passed.
  62  *              return_buffer       - Where to put method's return value (if
  63  *                                    any).  If NULL, no value is returned.
  64  *              return_type         - Expected type of return object
  65  *
  66  * RETURN:      Status
  67  *
  68  * DESCRIPTION: Find and evaluate the given object, passing the given
  69  *              parameters if necessary.  One of "Handle" or "Pathname" must
  70  *              be valid (non-null)
  71  *
  72  ******************************************************************************/
  73 acpi_status
  74 acpi_evaluate_object_typed(acpi_handle handle,
  75                            acpi_string pathname,
  76                            struct acpi_object_list * external_params,
  77                            struct acpi_buffer * return_buffer,
  78                            acpi_object_type return_type)
  79 {
  80         acpi_status status;
  81         u8 must_free = FALSE;
  82
  83         ACPI_FUNCTION_TRACE(acpi_evaluate_object_typed);
  84
  85         /* Return buffer must be valid */
  86
  87         if (!return_buffer) {
  88                 return_ACPI_STATUS(AE_BAD_PARAMETER);
  89         }
  90
  91         if (return_buffer->length == ACPI_ALLOCATE_BUFFER) {
  92                 must_free = TRUE;
  93         }
  94
  95         /* Evaluate the object */
  96
  97         status =
  98             acpi_evaluate_object(handle, pathname, external_params,
  99                                  return_buffer);
 100         if (ACPI_FAILURE(status)) {
 101                 return_ACPI_STATUS(status);
 102         }
 103
 104         /* Type ANY means "don't care" */
 105
 106         if (return_type == ACPI_TYPE_ANY) {
 107                 return_ACPI_STATUS(AE_OK);
 108         }
 109
 110         if (return_buffer->length == 0) {
 111
 112                 /* Error because caller specifically asked for a return value */
 113
 114                 ACPI_ERROR((AE_INFO, "No return value"));
 115                 return_ACPI_STATUS(AE_NULL_OBJECT);
 116         }
 117
 118         /* Examine the object type returned from evaluate_object */
 119
 120         if (((union acpi_object *)return_buffer->pointer)->type == return_type) {
 121                 return_ACPI_STATUS(AE_OK);
 122         }
 123
 124         /* Return object type does not match requested type */
 125
 126         ACPI_ERROR((AE_INFO,
 127                     "Incorrect return type [%s] requested [%s]",
 128                     acpi_ut_get_type_name(((union acpi_object *)return_buffer->
 129                                            pointer)->type),
 130                     acpi_ut_get_type_name(return_type)));
 131
 132         if (must_free) {
 133
 134                 /* Caller used ACPI_ALLOCATE_BUFFER, free the return buffer */
 135
 136                 acpi_os_free(return_buffer->pointer);
 137                 return_buffer->pointer = NULL;
 138         }
 139
 140         return_buffer->length = 0;
 141         return_ACPI_STATUS(AE_TYPE);
 142 }
 143
 144 ACPI_EXPORT_SYMBOL(acpi_evaluate_object_typed)
 145 #endif                          /*  ACPI_FUTURE_USAGE  */
 146
 147 /*******************************************************************************
 148  *
 149  * FUNCTION:    acpi_evaluate_object
 150  *
 151  * PARAMETERS:  Handle              - Object handle (optional)
 152  *              Pathname            - Object pathname (optional)
 153  *              external_params     - List of parameters to pass to method,
 154  *                                    terminated by NULL.  May be NULL
 155  *                                    if no parameters are being passed.
 156  *              return_buffer       - Where to put method's return value (if
 157  *                                    any).  If NULL, no value is returned.
 158  *
 159  * RETURN:      Status
 160  *
 161  * DESCRIPTION: Find and evaluate the given object, passing the given
 162  *              parameters if necessary.  One of "Handle" or "Pathname" must
 163  *              be valid (non-null)
 164  *
 165  ******************************************************************************/
 166 acpi_status
 167 acpi_evaluate_object(acpi_handle handle,
 168                      acpi_string pathname,
 169                      struct acpi_object_list *external_params,
 170                      struct acpi_buffer *return_buffer)
 171 {
 172         acpi_status status;
 173         acpi_status status2;
 174         struct acpi_parameter_info info;
 175         acpi_size buffer_space_needed;
 176         u32 i;
 177
 178         ACPI_FUNCTION_TRACE(acpi_evaluate_object);
 179
 180         info.node = handle;
 181         info.parameters = NULL;
 182         info.return_object = NULL;
 183         info.parameter_type = ACPI_PARAM_ARGS;
 184
 185         /*
 186          * If there are parameters to be passed to the object
 187          * (which must be a control method), the external objects
 188          * must be converted to internal objects
 189          */
 190         if (external_params && external_params->count) {
 191                 /*
 192                  * Allocate a new parameter block for the internal objects
 193                  * Add 1 to count to allow for null terminated internal list
 194                  */
 195                 info.parameters = ACPI_ALLOCATE_ZEROED(((acpi_size)
 196                                                         external_params->count +
 197                                                         1) * sizeof(void *));
 198                 if (!info.parameters) {
 199                         return_ACPI_STATUS(AE_NO_MEMORY);
 200                 }
 201
 202                 /*
 203                  * Convert each external object in the list to an
 204                  * internal object
 205                  */
 206                 for (i = 0; i < external_params->count; i++) {
 207                         status =
 208                             acpi_ut_copy_eobject_to_iobject(&external_params->
 209                                                             pointer[i],
 210                                                             &info.
 211                                                             parameters[i]);
 212                         if (ACPI_FAILURE(status)) {
 213                                 acpi_ut_delete_internal_object_list(info.
 214                                                                     parameters);
 215                                 return_ACPI_STATUS(status);
 216                         }
 217                 }
 218                 info.parameters[external_params->count] = NULL;
 219         }
 220
 221         /*
 222          * Three major cases:
 223          * 1) Fully qualified pathname
 224          * 2) No handle, not fully qualified pathname (error)
 225          * 3) Valid handle
 226          */
 227         if ((pathname) && (acpi_ns_valid_root_prefix(pathname[0]))) {
 228
 229                 /* The path is fully qualified, just evaluate by name */
 230
 231                 status = acpi_ns_evaluate_by_name(pathname, &info);
 232         } else if (!handle) {
 233                 /*
 234                  * A handle is optional iff a fully qualified pathname
 235                  * is specified.  Since we've already handled fully
 236                  * qualified names above, this is an error
 237                  */
 238                 if (!pathname) {
 239                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 240                                           "Both Handle and Pathname are NULL"));
 241                 } else {
 242                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 243                                           "Null Handle with relative pathname [%s]",
 244                                           pathname));
 245                 }
 246
 247                 status = AE_BAD_PARAMETER;
 248         } else {
 249                 /*
 250                  * We get here if we have a handle -- and if we have a
 251                  * pathname it is relative.  The handle will be validated
 252                  * in the lower procedures
 253                  */
 254                 if (!pathname) {
 255                         /*
 256                          * The null pathname case means the handle is for
 257                          * the actual object to be evaluated
 258                          */
 259                         status = acpi_ns_evaluate_by_handle(&info);
 260                 } else {
 261                         /* Both a Handle and a relative Pathname */
 262
 263                         status = acpi_ns_evaluate_relative(pathname, &info);
 264                 }
 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                                  * Find out how large a buffer is needed
 293                                  * to contain the returned object
 294                                  */
 295                                 status =
 296                                     acpi_ut_get_object_size(info.return_object,
 297                                                             &buffer_space_needed);
 298                                 if (ACPI_SUCCESS(status)) {
 299
 300                                         /* Validate/Allocate/Clear caller buffer */
 301
 302                                         status =
 303                                             acpi_ut_initialize_buffer
 304                                             (return_buffer,
 305                                              buffer_space_needed);
 306                                         if (ACPI_FAILURE(status)) {
 307                                                 /*
 308                                                  * Caller's buffer is too small or a new one can't
 309                                                  * be allocated
 310                                                  */
 311                                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 312                                                                   "Needed buffer size %X, %s\n",
 313                                                                   (u32)
 314                                                                   buffer_space_needed,
 315                                                                   acpi_format_exception
 316                                                                   (status)));
 317                                         } else {
 318                                                 /* We have enough space for the object, build it */
 319
 320                                                 status =
 321                                                     acpi_ut_copy_iobject_to_eobject
 322                                                     (info.return_object,
 323                                                      return_buffer);
 324                                         }
 325                                 }
 326                         }
 327                 }
 328         }
 329
 330         if (info.return_object) {
 331                 /*
 332                  * Delete the internal return object.  NOTE: Interpreter
 333                  * must be locked to avoid race condition.
 334                  */
 335                 status2 = acpi_ex_enter_interpreter();
 336                 if (ACPI_SUCCESS(status2)) {
 337                         /*
 338                          * Delete the internal return object. (Or at least
 339                          * decrement the reference count by one)
 340                          */
 341                         acpi_ut_remove_reference(info.return_object);
 342                         acpi_ex_exit_interpreter();
 343                 }
 344         }
 345
 346         /* Free the input parameter list (if we created one) */
 347
 348         if (info.parameters) {
 349
 350                 /* Free the allocated parameter block */
 351
 352                 acpi_ut_delete_internal_object_list(info.parameters);
 353         }
 354
 355         return_ACPI_STATUS(status);
 356 }
 357
 358 ACPI_EXPORT_SYMBOL(acpi_evaluate_object)
 359
 360 /*******************************************************************************
 361  *
 362  * FUNCTION:    acpi_walk_namespace
 363  *
 364  * PARAMETERS:  Type                - acpi_object_type to search for
 365  *              start_object        - Handle in namespace where search begins
 366  *              max_depth           - Depth to which search is to reach
 367  *              user_function       - Called when an object of "Type" is found
 368  *              Context             - Passed to user function
 369  *              return_value        - Location where return value of
 370  *                                    user_function is put if terminated early
 371  *
 372  * RETURNS      Return value from the user_function if terminated early.
 373  *              Otherwise, returns NULL.
 374  *
 375  * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
 376  *              starting (and ending) at the object specified by start_handle.
 377  *              The user_function is called whenever an object that matches
 378  *              the type parameter is found.  If the user function returns
 379  *              a non-zero value, the search is terminated immediately and this
 380  *              value is returned to the caller.
 381  *
 382  *              The point of this procedure is to provide a generic namespace
 383  *              walk routine that can be called from multiple places to
 384  *              provide multiple services;  the User Function can be tailored
 385  *              to each task, whether it is a print function, a compare
 386  *              function, etc.
 387  *
 388  ******************************************************************************/
 389 acpi_status
 390 acpi_walk_namespace(acpi_object_type type,
 391                     acpi_handle start_object,
 392                     u32 max_depth,
 393                     acpi_walk_callback user_function,
 394                     void *context, void **return_value)
 395 {
 396         acpi_status status;
 397
 398         ACPI_FUNCTION_TRACE(acpi_walk_namespace);
 399
 400         /* Parameter validation */
 401
 402         if ((type > ACPI_TYPE_LOCAL_MAX) || (!max_depth) || (!user_function)) {
 403                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 404         }
 405
 406         /*
 407          * Lock the namespace around the walk.
 408          * The namespace will be unlocked/locked around each call
 409          * to the user function - since this function
 410          * must be allowed to make Acpi calls itself.
 411          */
 412         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 413         if (ACPI_FAILURE(status)) {
 414                 return_ACPI_STATUS(status);
 415         }
 416
 417         status = acpi_ns_walk_namespace(type, start_object, max_depth,
 418                                         ACPI_NS_WALK_UNLOCK,
 419                                         user_function, context, return_value);
 420
 421         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 422         return_ACPI_STATUS(status);
 423 }
 424
 425 ACPI_EXPORT_SYMBOL(acpi_walk_namespace)
 426
 427 /*******************************************************************************
 428  *
 429  * FUNCTION:    acpi_ns_get_device_callback
 430  *
 431  * PARAMETERS:  Callback from acpi_get_device
 432  *
 433  * RETURN:      Status
 434  *
 435  * DESCRIPTION: Takes callbacks from walk_namespace and filters out all non-
 436  *              present devices, or if they specified a HID, it filters based
 437  *              on that.
 438  *
 439  ******************************************************************************/
 440 static acpi_status
 441 acpi_ns_get_device_callback(acpi_handle obj_handle,
 442                             u32 nesting_level,
 443                             void *context, void **return_value)
 444 {
 445         struct acpi_get_devices_info *info = context;
 446         acpi_status status;
 447         struct acpi_namespace_node *node;
 448         u32 flags;
 449         struct acpi_device_id hid;
 450         struct acpi_compatible_id_list *cid;
 451         acpi_native_uint i;
 452
 453         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 454         if (ACPI_FAILURE(status)) {
 455                 return (status);
 456         }
 457
 458         node = acpi_ns_map_handle_to_node(obj_handle);
 459         status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 460         if (ACPI_FAILURE(status)) {
 461                 return (status);
 462         }
 463
 464         if (!node) {
 465                 return (AE_BAD_PARAMETER);
 466         }
 467
 468         /* Run _STA to determine if device is present */
 469
 470         status = acpi_ut_execute_STA(node, &flags);
 471         if (ACPI_FAILURE(status)) {
 472                 return (AE_CTRL_DEPTH);
 473         }
 474
 475         if (!(flags & ACPI_STA_DEVICE_PRESENT)) {
 476
 477                 /* Don't examine children of the device if not present */
 478
 479                 return (AE_CTRL_DEPTH);
 480         }
 481
 482         /* Filter based on device HID & CID */
 483
 484         if (info->hid != NULL) {
 485                 status = acpi_ut_execute_HID(node, &hid);
 486                 if (status == AE_NOT_FOUND) {
 487                         return (AE_OK);
 488                 } else if (ACPI_FAILURE(status)) {
 489                         return (AE_CTRL_DEPTH);
 490                 }
 491
 492                 if (ACPI_STRNCMP(hid.value, info->hid, sizeof(hid.value)) != 0) {
 493
 494                         /* Get the list of Compatible IDs */
 495
 496                         status = acpi_ut_execute_CID(node, &cid);
 497                         if (status == AE_NOT_FOUND) {
 498                                 return (AE_OK);
 499                         } else if (ACPI_FAILURE(status)) {
 500                                 return (AE_CTRL_DEPTH);
 501                         }
 502
 503                         /* Walk the CID list */
 504
 505                         for (i = 0; i < cid->count; i++) {
 506                                 if (ACPI_STRNCMP(cid->id[i].value, info->hid,
 507                                                  sizeof(struct
 508                                                         acpi_compatible_id)) !=
 509                                     0) {
 510                                         ACPI_FREE(cid);
 511                                         return (AE_OK);
 512                                 }
 513                         }
 514                         ACPI_FREE(cid);
 515                 }
 516         }
 517
 518         status = info->user_function(obj_handle, nesting_level, info->context,
 519                                      return_value);
 520         return (status);
 521 }
 522
 523 /*******************************************************************************
 524  *
 525  * FUNCTION:    acpi_get_devices
 526  *
 527  * PARAMETERS:  HID                 - HID to search for. Can be NULL.
 528  *              user_function       - Called when a matching object is found
 529  *              Context             - Passed to user function
 530  *              return_value        - Location where return value of
 531  *                                    user_function is put if terminated early
 532  *
 533  * RETURNS      Return value from the user_function if terminated early.
 534  *              Otherwise, returns NULL.
 535  *
 536  * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
 537  *              starting (and ending) at the object specified by start_handle.
 538  *              The user_function is called whenever an object of type
 539  *              Device is found.  If the user function returns
 540  *              a non-zero value, the search is terminated immediately and this
 541  *              value is returned to the caller.
 542  *
 543  *              This is a wrapper for walk_namespace, but the callback performs
 544  *              additional filtering. Please see acpi_get_device_callback.
 545  *
 546  ******************************************************************************/
 547
 548 acpi_status
 549 acpi_get_devices(char *HID,
 550                  acpi_walk_callback user_function,
 551                  void *context, void **return_value)
 552 {
 553         acpi_status status;
 554         struct acpi_get_devices_info info;
 555
 556         ACPI_FUNCTION_TRACE(acpi_get_devices);
 557
 558         /* Parameter validation */
 559
 560         if (!user_function) {
 561                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 562         }
 563
 564         /*
 565          * We're going to call their callback from OUR callback, so we need
 566          * to know what it is, and their context parameter.
 567          */
 568         info.hid = HID;
 569         info.context = context;
 570         info.user_function = user_function;
 571
 572         /*
 573          * Lock the namespace around the walk.
 574          * The namespace will be unlocked/locked around each call
 575          * to the user function - since this function
 576          * must be allowed to make Acpi calls itself.
 577          */
 578         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 579         if (ACPI_FAILURE(status)) {
 580                 return_ACPI_STATUS(status);
 581         }
 582
 583         status = acpi_ns_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
 584                                         ACPI_UINT32_MAX, ACPI_NS_WALK_UNLOCK,
 585                                         acpi_ns_get_device_callback, &info,
 586                                         return_value);
 587
 588         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 589         return_ACPI_STATUS(status);
 590 }
 591
 592 ACPI_EXPORT_SYMBOL(acpi_get_devices)
 593
 594 /*******************************************************************************
 595  *
 596  * FUNCTION:    acpi_attach_data
 597  *
 598  * PARAMETERS:  obj_handle          - Namespace node
 599  *              Handler             - Handler for this attachment
 600  *              Data                - Pointer to data to be attached
 601  *
 602  * RETURN:      Status
 603  *
 604  * DESCRIPTION: Attach arbitrary data and handler to a namespace node.
 605  *
 606  ******************************************************************************/
 607 acpi_status
 608 acpi_attach_data(acpi_handle obj_handle,
 609                  acpi_object_handler handler, void *data)
 610 {
 611         struct acpi_namespace_node *node;
 612         acpi_status status;
 613
 614         /* Parameter validation */
 615
 616         if (!obj_handle || !handler || !data) {
 617                 return (AE_BAD_PARAMETER);
 618         }
 619
 620         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 621         if (ACPI_FAILURE(status)) {
 622                 return (status);
 623         }
 624
 625         /* Convert and validate the handle */
 626
 627         node = acpi_ns_map_handle_to_node(obj_handle);
 628         if (!node) {
 629                 status = AE_BAD_PARAMETER;
 630                 goto unlock_and_exit;
 631         }
 632
 633         status = acpi_ns_attach_data(node, handler, data);
 634
 635       unlock_and_exit:
 636         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 637         return (status);
 638 }
 639
 640 ACPI_EXPORT_SYMBOL(acpi_attach_data)
 641
 642 /*******************************************************************************
 643  *
 644  * FUNCTION:    acpi_detach_data
 645  *
 646  * PARAMETERS:  obj_handle          - Namespace node handle
 647  *              Handler             - Handler used in call to acpi_attach_data
 648  *
 649  * RETURN:      Status
 650  *
 651  * DESCRIPTION: Remove data that was previously attached to a node.
 652  *
 653  ******************************************************************************/
 654 acpi_status
 655 acpi_detach_data(acpi_handle obj_handle, acpi_object_handler handler)
 656 {
 657         struct acpi_namespace_node *node;
 658         acpi_status status;
 659
 660         /* Parameter validation */
 661
 662         if (!obj_handle || !handler) {
 663                 return (AE_BAD_PARAMETER);
 664         }
 665
 666         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 667         if (ACPI_FAILURE(status)) {
 668                 return (status);
 669         }
 670
 671         /* Convert and validate the handle */
 672
 673         node = acpi_ns_map_handle_to_node(obj_handle);
 674         if (!node) {
 675                 status = AE_BAD_PARAMETER;
 676                 goto unlock_and_exit;
 677         }
 678
 679         status = acpi_ns_detach_data(node, handler);
 680
 681       unlock_and_exit:
 682         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 683         return (status);
 684 }
 685
 686 ACPI_EXPORT_SYMBOL(acpi_detach_data)
 687
 688 /*******************************************************************************
 689  *
 690  * FUNCTION:    acpi_get_data
 691  *
 692  * PARAMETERS:  obj_handle          - Namespace node
 693  *              Handler             - Handler used in call to attach_data
 694  *              Data                - Where the data is returned
 695  *
 696  * RETURN:      Status
 697  *
 698  * DESCRIPTION: Retrieve data that was previously attached to a namespace node.
 699  *
 700  ******************************************************************************/
 701 acpi_status
 702 acpi_get_data(acpi_handle obj_handle, acpi_object_handler handler, void **data)
 703 {
 704         struct acpi_namespace_node *node;
 705         acpi_status status;
 706
 707         /* Parameter validation */
 708
 709         if (!obj_handle || !handler || !data) {
 710                 return (AE_BAD_PARAMETER);
 711         }
 712
 713         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 714         if (ACPI_FAILURE(status)) {
 715                 return (status);
 716         }
 717
 718         /* Convert and validate the handle */
 719
 720         node = acpi_ns_map_handle_to_node(obj_handle);
 721         if (!node) {
 722                 status = AE_BAD_PARAMETER;
 723                 goto unlock_and_exit;
 724         }
 725
 726         status = acpi_ns_get_attached_data(node, handler, data);
 727
 728       unlock_and_exit:
 729         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 730         return (status);
 731 }
 732
 733 ACPI_EXPORT_SYMBOL(acpi_get_data)