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 - 2005, 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 <linux/module.h>
  46
  47 #include <acpi/acpi.h>
  48 #include <acpi/acnamesp.h>
  49 #include <acpi/acinterp.h>
  50
  51 #define _COMPONENT          ACPI_NAMESPACE
  52 ACPI_MODULE_NAME("nsxfeval")
  53
  54 /*******************************************************************************
  55  *
  56  * FUNCTION:    acpi_evaluate_object_typed
  57  *
  58  * PARAMETERS:  Handle              - Object handle (optional)
  59  *              Pathname            - Object pathname (optional)
  60  *              external_params     - List of parameters to pass to method,
  61  *                                    terminated by NULL.  May be NULL
  62  *                                    if no parameters are being passed.
  63  *              return_buffer       - Where to put method's return value (if
  64  *                                    any).  If NULL, no value is returned.
  65  *              return_type         - Expected type of return object
  66  *
  67  * RETURN:      Status
  68  *
  69  * DESCRIPTION: Find and evaluate the given object, passing the given
  70  *              parameters if necessary.  One of "Handle" or "Pathname" must
  71  *              be valid (non-null)
  72  *
  73  ******************************************************************************/
  74 #ifdef ACPI_FUTURE_USAGE
  75 acpi_status
  76 acpi_evaluate_object_typed(acpi_handle handle,
  77                            acpi_string pathname,
  78                            struct acpi_object_list *external_params,
  79                            struct acpi_buffer *return_buffer,
  80                            acpi_object_type return_type)
  81 {
  82         acpi_status status;
  83         u8 must_free = FALSE;
  84
  85         ACPI_FUNCTION_TRACE("acpi_evaluate_object_typed");
  86
  87         /* Return buffer must be valid */
  88
  89         if (!return_buffer) {
  90                 return_ACPI_STATUS(AE_BAD_PARAMETER);
  91         }
  92
  93         if (return_buffer->length == ACPI_ALLOCATE_BUFFER) {
  94                 must_free = TRUE;
  95         }
  96
  97         /* Evaluate the object */
  98
  99         status =
 100             acpi_evaluate_object(handle, pathname, external_params,
 101                                  return_buffer);
 102         if (ACPI_FAILURE(status)) {
 103                 return_ACPI_STATUS(status);
 104         }
 105
 106         /* Type ANY means "don't care" */
 107
 108         if (return_type == ACPI_TYPE_ANY) {
 109                 return_ACPI_STATUS(AE_OK);
 110         }
 111
 112         if (return_buffer->length == 0) {
 113                 /* Error because caller specifically asked for a return value */
 114
 115                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "No return value\n"));
 116
 117                 return_ACPI_STATUS(AE_NULL_OBJECT);
 118         }
 119
 120         /* Examine the object type returned from evaluate_object */
 121
 122         if (((union acpi_object *)return_buffer->pointer)->type == return_type) {
 123                 return_ACPI_STATUS(AE_OK);
 124         }
 125
 126         /* Return object type does not match requested type */
 127
 128         ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 129                           "Incorrect return type [%s] requested [%s]\n",
 130                           acpi_ut_get_type_name(((union acpi_object *)
 131                                                  return_buffer->pointer)->type),
 132                           acpi_ut_get_type_name(return_type)));
 133
 134         if (must_free) {
 135                 /* Caller used ACPI_ALLOCATE_BUFFER, free the return buffer */
 136
 137                 acpi_os_free(return_buffer->pointer);
 138                 return_buffer->pointer = NULL;
 139         }
 140
 141         return_buffer->length = 0;
 142         return_ACPI_STATUS(AE_TYPE);
 143 }
 144 #endif                          /*  ACPI_FUTURE_USAGE  */
 145
 146 /*******************************************************************************
 147  *
 148  * FUNCTION:    acpi_evaluate_object
 149  *
 150  * PARAMETERS:  Handle              - Object handle (optional)
 151  *              Pathname            - Object pathname (optional)
 152  *              external_params     - List of parameters to pass to method,
 153  *                                    terminated by NULL.  May be NULL
 154  *                                    if no parameters are being passed.
 155  *              return_buffer       - Where to put method's return value (if
 156  *                                    any).  If NULL, no value is returned.
 157  *
 158  * RETURN:      Status
 159  *
 160  * DESCRIPTION: Find and evaluate the given object, passing the given
 161  *              parameters if necessary.  One of "Handle" or "Pathname" must
 162  *              be valid (non-null)
 163  *
 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_MEM_CALLOCATE(((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_ERROR,
 240                                           "Both Handle and Pathname are NULL\n"));
 241                 } else {
 242                         ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 243                                           "Handle is NULL and Pathname is relative\n"));
 244                 }
 245
 246                 status = AE_BAD_PARAMETER;
 247         } else {
 248                 /*
 249                  * We get here if we have a handle -- and if we have a
 250                  * pathname it is relative.  The handle will be validated
 251                  * in the lower procedures
 252                  */
 253                 if (!pathname) {
 254                         /*
 255                          * The null pathname case means the handle is for
 256                          * the actual object to be evaluated
 257                          */
 258                         status = acpi_ns_evaluate_by_handle(&info);
 259                 } else {
 260                         /*
 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                                         /* Validate/Allocate/Clear caller buffer */
 300
 301                                         status =
 302                                             acpi_ut_initialize_buffer
 303                                             (return_buffer,
 304                                              buffer_space_needed);
 305                                         if (ACPI_FAILURE(status)) {
 306                                                 /*
 307                                                  * Caller's buffer is too small or a new one can't be allocated
 308                                                  */
 309                                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 310                                                                   "Needed buffer size %X, %s\n",
 311                                                                   (u32)
 312                                                                   buffer_space_needed,
 313                                                                   acpi_format_exception
 314                                                                   (status)));
 315                                         } else {
 316                                                 /*
 317                                                  *  We have enough space for the object, build it
 318                                                  */
 319                                                 status =
 320                                                     acpi_ut_copy_iobject_to_eobject
 321                                                     (info.return_object,
 322                                                      return_buffer);
 323                                         }
 324                                 }
 325                         }
 326                 }
 327         }
 328
 329         if (info.return_object) {
 330                 /*
 331                  * Delete the internal return object.  NOTE: Interpreter
 332                  * must be locked to avoid race condition.
 333                  */
 334                 status2 = acpi_ex_enter_interpreter();
 335                 if (ACPI_SUCCESS(status2)) {
 336                         /*
 337                          * Delete the internal return object. (Or at least
 338                          * decrement the reference count by one)
 339                          */
 340                         acpi_ut_remove_reference(info.return_object);
 341                         acpi_ex_exit_interpreter();
 342                 }
 343         }
 344
 345         /*
 346          * Free the input parameter list (if we created one),
 347          */
 348         if (info.parameters) {
 349                 /* Free the allocated parameter block */
 350
 351                 acpi_ut_delete_internal_object_list(info.parameters);
 352         }
 353
 354         return_ACPI_STATUS(status);
 355 }
 356
 357 EXPORT_SYMBOL(acpi_evaluate_object);
 358
 359 /*******************************************************************************
 360  *
 361  * FUNCTION:    acpi_walk_namespace
 362  *
 363  * PARAMETERS:  Type                - acpi_object_type to search for
 364  *              start_object        - Handle in namespace where search begins
 365  *              max_depth           - Depth to which search is to reach
 366  *              user_function       - Called when an object of "Type" is found
 367  *              Context             - Passed to user function
 368  *              return_value        - Location where return value of
 369  *                                    user_function is put if terminated early
 370  *
 371  * RETURNS      Return value from the user_function if terminated early.
 372  *              Otherwise, returns NULL.
 373  *
 374  * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
 375  *              starting (and ending) at the object specified by start_handle.
 376  *              The user_function is called whenever an object that matches
 377  *              the type parameter is found.  If the user function returns
 378  *              a non-zero value, the search is terminated immediately and this
 379  *              value is returned to the caller.
 380  *
 381  *              The point of this procedure is to provide a generic namespace
 382  *              walk routine that can be called from multiple places to
 383  *              provide multiple services;  the User Function can be tailored
 384  *              to each task, whether it is a print function, a compare
 385  *              function, etc.
 386  *
 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_EXTERNAL_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 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
 441 static acpi_status
 442 acpi_ns_get_device_callback(acpi_handle obj_handle,
 443                             u32 nesting_level,
 444                             void *context, void **return_value)
 445 {
 446         struct acpi_get_devices_info *info = context;
 447         acpi_status status;
 448         struct acpi_namespace_node *node;
 449         u32 flags;
 450         struct acpi_device_id hid;
 451         struct acpi_compatible_id_list *cid;
 452         acpi_native_uint i;
 453
 454         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 455         if (ACPI_FAILURE(status)) {
 456                 return (status);
 457         }
 458
 459         node = acpi_ns_map_handle_to_node(obj_handle);
 460         status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 461         if (ACPI_FAILURE(status)) {
 462                 return (status);
 463         }
 464
 465         if (!node) {
 466                 return (AE_BAD_PARAMETER);
 467         }
 468
 469         /* Run _STA to determine if device is present */
 470
 471         status = acpi_ut_execute_STA(node, &flags);
 472         if (ACPI_FAILURE(status)) {
 473                 return (AE_CTRL_DEPTH);
 474         }
 475
 476         if (!(flags & 0x01)) {
 477                 /* Don't return at the device or children of the device if not there */
 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                         /* Get the list of Compatible IDs */
 494
 495                         status = acpi_ut_execute_CID(node, &cid);
 496                         if (status == AE_NOT_FOUND) {
 497                                 return (AE_OK);
 498                         } else if (ACPI_FAILURE(status)) {
 499                                 return (AE_CTRL_DEPTH);
 500                         }
 501
 502                         /* Walk the CID list */
 503
 504                         for (i = 0; i < cid->count; i++) {
 505                                 if (ACPI_STRNCMP(cid->id[i].value, info->hid,
 506                                                  sizeof(struct
 507                                                         acpi_compatible_id)) !=
 508                                     0) {
 509                                         ACPI_MEM_FREE(cid);
 510                                         return (AE_OK);
 511                                 }
 512                         }
 513                         ACPI_MEM_FREE(cid);
 514                 }
 515         }
 516
 517         status = info->user_function(obj_handle, nesting_level, info->context,
 518                                      return_value);
 519         return (status);
 520 }
 521
 522 /*******************************************************************************
 523  *
 524  * FUNCTION:    acpi_get_devices
 525  *
 526  * PARAMETERS:  HID                 - HID to search for. Can be NULL.
 527  *              user_function       - Called when a matching object is found
 528  *              Context             - Passed to user function
 529  *              return_value        - Location where return value of
 530  *                                    user_function is put if terminated early
 531  *
 532  * RETURNS      Return value from the user_function if terminated early.
 533  *              Otherwise, returns NULL.
 534  *
 535  * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
 536  *              starting (and ending) at the object specified by start_handle.
 537  *              The user_function is called whenever an object of type
 538  *              Device is found.  If the user function returns
 539  *              a non-zero value, the search is terminated immediately and this
 540  *              value is returned to the caller.
 541  *
 542  *              This is a wrapper for walk_namespace, but the callback performs
 543  *              additional filtering. Please see acpi_get_device_callback.
 544  *
 545  ******************************************************************************/
 546
 547 acpi_status
 548 acpi_get_devices(char *HID,
 549                  acpi_walk_callback user_function,
 550                  void *context, void **return_value)
 551 {
 552         acpi_status status;
 553         struct acpi_get_devices_info info;
 554
 555         ACPI_FUNCTION_TRACE("acpi_get_devices");
 556
 557         /* Parameter validation */
 558
 559         if (!user_function) {
 560                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 561         }
 562
 563         /*
 564          * We're going to call their callback from OUR callback, so we need
 565          * to know what it is, and their context parameter.
 566          */
 567         info.context = context;
 568         info.user_function = user_function;
 569         info.hid = HID;
 570
 571         /*
 572          * Lock the namespace around the walk.
 573          * The namespace will be unlocked/locked around each call
 574          * to the user function - since this function
 575          * must be allowed to make Acpi calls itself.
 576          */
 577         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 578         if (ACPI_FAILURE(status)) {
 579                 return_ACPI_STATUS(status);
 580         }
 581
 582         status = acpi_ns_walk_namespace(ACPI_TYPE_DEVICE,
 583                                         ACPI_ROOT_OBJECT, ACPI_UINT32_MAX,
 584                                         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 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
 608 acpi_status
 609 acpi_attach_data(acpi_handle obj_handle,
 610                  acpi_object_handler handler, void *data)
 611 {
 612         struct acpi_namespace_node *node;
 613         acpi_status status;
 614
 615         /* Parameter validation */
 616
 617         if (!obj_handle || !handler || !data) {
 618                 return (AE_BAD_PARAMETER);
 619         }
 620
 621         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 622         if (ACPI_FAILURE(status)) {
 623                 return (status);
 624         }
 625
 626         /* Convert and validate the handle */
 627
 628         node = acpi_ns_map_handle_to_node(obj_handle);
 629         if (!node) {
 630                 status = AE_BAD_PARAMETER;
 631                 goto unlock_and_exit;
 632         }
 633
 634         status = acpi_ns_attach_data(node, handler, data);
 635
 636       unlock_and_exit:
 637         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 638         return (status);
 639 }
 640
 641 /*******************************************************************************
 642  *
 643  * FUNCTION:    acpi_detach_data
 644  *
 645  * PARAMETERS:  obj_handle          - Namespace node handle
 646  *              Handler             - Handler used in call to acpi_attach_data
 647  *
 648  * RETURN:      Status
 649  *
 650  * DESCRIPTION: Remove data that was previously attached to a node.
 651  *
 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 /*******************************************************************************
 687  *
 688  * FUNCTION:    acpi_get_data
 689  *
 690  * PARAMETERS:  obj_handle          - Namespace node
 691  *              Handler             - Handler used in call to attach_data
 692  *              Data                - Where the data is returned
 693  *
 694  * RETURN:      Status
 695  *
 696  * DESCRIPTION: Retrieve data that was previously attached to a namespace node.
 697  *
 698  ******************************************************************************/
 699
 700 acpi_status
 701 acpi_get_data(acpi_handle obj_handle, acpi_object_handler handler, void **data)
 702 {
 703         struct acpi_namespace_node *node;
 704         acpi_status status;
 705
 706         /* Parameter validation */
 707
 708         if (!obj_handle || !handler || !data) {
 709                 return (AE_BAD_PARAMETER);
 710         }
 711
 712         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 713         if (ACPI_FAILURE(status)) {
 714                 return (status);
 715         }
 716
 717         /* Convert and validate the handle */
 718
 719         node = acpi_ns_map_handle_to_node(obj_handle);
 720         if (!node) {
 721                 status = AE_BAD_PARAMETER;
 722                 goto unlock_and_exit;
 723         }
 724
 725         status = acpi_ns_get_attached_data(node, handler, data);
 726
 727       unlock_and_exit:
 728         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 729         return (status);
 730 }