git.oblomov.eu Git - linux-2.6/blob - 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 - 2007, 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_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_evaluate_info *info;
 175         acpi_size buffer_space_needed;
 176         u32 i;
 177
 178         ACPI_FUNCTION_TRACE(acpi_evaluate_object);
 179
 180         /* Allocate and initialize the evaluation information block */
 181
 182         info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
 183         if (!info) {
 184                 return_ACPI_STATUS(AE_NO_MEMORY);
 185         }
 186
 187         info->pathname = pathname;
 188         info->parameter_type = ACPI_PARAM_ARGS;
 189
 190         /* Convert and validate the device handle */
 191
 192         info->prefix_node = acpi_ns_map_handle_to_node(handle);
 193         if (!info->prefix_node) {
 194                 status = AE_BAD_PARAMETER;
 195                 goto cleanup;
 196         }
 197
 198         /*
 199          * If there are parameters to be passed to a control method, the external
 200          * objects must all be converted to internal objects
 201          */
 202         if (external_params && external_params->count) {
 203                 /*
 204                  * Allocate a new parameter block for the internal objects
 205                  * Add 1 to count to allow for null terminated internal list
 206                  */
 207                 info->parameters = ACPI_ALLOCATE_ZEROED(((acpi_size)
 208                                                          external_params->
 209                                                          count +
 210                                                          1) * sizeof(void *));
 211                 if (!info->parameters) {
 212                         status = AE_NO_MEMORY;
 213                         goto cleanup;
 214                 }
 215
 216                 /* Convert each external object in the list to an internal object */
 217
 218                 for (i = 0; i < external_params->count; i++) {
 219                         status =
 220                             acpi_ut_copy_eobject_to_iobject(&external_params->
 221                                                             pointer[i],
 222                                                             &info->
 223                                                             parameters[i]);
 224                         if (ACPI_FAILURE(status)) {
 225                                 goto cleanup;
 226                         }
 227                 }
 228                 info->parameters[external_params->count] = NULL;
 229         }
 230
 231         /*
 232          * Three major cases:
 233          * 1) Fully qualified pathname
 234          * 2) No handle, not fully qualified pathname (error)
 235          * 3) Valid handle
 236          */
 237         if ((pathname) && (acpi_ns_valid_root_prefix(pathname[0]))) {
 238
 239                 /* The path is fully qualified, just evaluate by name */
 240
 241                 info->prefix_node = NULL;
 242                 status = acpi_ns_evaluate(info);
 243         } else if (!handle) {
 244                 /*
 245                  * A handle is optional iff a fully qualified pathname is specified.
 246                  * Since we've already handled fully qualified names above, this is
 247                  * an error
 248                  */
 249                 if (!pathname) {
 250                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 251                                           "Both Handle and Pathname are NULL"));
 252                 } else {
 253                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 254                                           "Null Handle with relative pathname [%s]",
 255                                           pathname));
 256                 }
 257
 258                 status = AE_BAD_PARAMETER;
 259         } else {
 260                 /* We have a namespace a node and a possible relative path */
 261
 262                 status = acpi_ns_evaluate(info);
 263         }
 264
 265         /*
 266          * If we are expecting a return value, and all went well above,
 267          * copy the return value to an external object.
 268          */
 269         if (return_buffer) {
 270                 if (!info->return_object) {
 271                         return_buffer->length = 0;
 272                 } else {
 273                         if (ACPI_GET_DESCRIPTOR_TYPE(info->return_object) ==
 274                             ACPI_DESC_TYPE_NAMED) {
 275                                 /*
 276                                  * If we received a NS Node as a return object, this means that
 277                                  * the object we are evaluating has nothing interesting to
 278                                  * return (such as a mutex, etc.)  We return an error because
 279                                  * these types are essentially unsupported by this interface.
 280                                  * We don't check up front because this makes it easier to add
 281                                  * support for various types at a later date if necessary.
 282                                  */
 283                                 status = AE_TYPE;
 284                                 info->return_object = NULL;     /* No need to delete a NS Node */
 285                                 return_buffer->length = 0;
 286                         }
 287
 288                         if (ACPI_SUCCESS(status)) {
 289
 290                                 /* Get the size of the returned object */
 291
 292                                 status =
 293                                     acpi_ut_get_object_size(info->return_object,
 294                                                             &buffer_space_needed);
 295                                 if (ACPI_SUCCESS(status)) {
 296
 297                                         /* Validate/Allocate/Clear caller buffer */
 298
 299                                         status =
 300                                             acpi_ut_initialize_buffer
 301                                             (return_buffer,
 302                                              buffer_space_needed);
 303                                         if (ACPI_FAILURE(status)) {
 304                                                 /*
 305                                                  * Caller's buffer is too small or a new one can't
 306                                                  * be allocated
 307                                                  */
 308                                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 309                                                                   "Needed buffer size %X, %s\n",
 310                                                                   (u32)
 311                                                                   buffer_space_needed,
 312                                                                   acpi_format_exception
 313                                                                   (status)));
 314                                         } else {
 315                                                 /* We have enough space for the object, build it */
 316
 317                                                 status =
 318                                                     acpi_ut_copy_iobject_to_eobject
 319                                                     (info->return_object,
 320                                                      return_buffer);
 321                                         }
 322                                 }
 323                         }
 324                 }
 325         }
 326
 327         if (info->return_object) {
 328                 /*
 329                  * Delete the internal return object. NOTE: Interpreter must be
 330                  * locked to avoid race condition.
 331                  */
 332                 status2 = acpi_ex_enter_interpreter();
 333                 if (ACPI_SUCCESS(status2)) {
 334
 335                         /* Remove one reference on the return object (should delete it) */
 336
 337                         acpi_ut_remove_reference(info->return_object);
 338                         acpi_ex_exit_interpreter();
 339                 }
 340         }
 341
 342       cleanup:
 343
 344         /* Free the input parameter list (if we created one) */
 345
 346         if (info->parameters) {
 347
 348                 /* Free the allocated parameter block */
 349
 350                 acpi_ut_delete_internal_object_list(info->parameters);
 351         }
 352
 353         ACPI_FREE(info);
 354         return_ACPI_STATUS(status);
 355 }
 356
 357 ACPI_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 acpi_status
 389 acpi_walk_namespace(acpi_object_type type,
 390                     acpi_handle start_object,
 391                     u32 max_depth,
 392                     acpi_walk_callback user_function,
 393                     void *context, void **return_value)
 394 {
 395         acpi_status status;
 396
 397         ACPI_FUNCTION_TRACE(acpi_walk_namespace);
 398
 399         /* Parameter validation */
 400
 401         if ((type > ACPI_TYPE_LOCAL_MAX) || (!max_depth) || (!user_function)) {
 402                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 403         }
 404
 405         /*
 406          * Lock the namespace around the walk.
 407          * The namespace will be unlocked/locked around each call
 408          * to the user function - since this function
 409          * must be allowed to make Acpi calls itself.
 410          */
 411         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 412         if (ACPI_FAILURE(status)) {
 413                 return_ACPI_STATUS(status);
 414         }
 415
 416         status = acpi_ns_walk_namespace(type, start_object, max_depth,
 417                                         ACPI_NS_WALK_UNLOCK,
 418                                         user_function, context, return_value);
 419
 420         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 421         return_ACPI_STATUS(status);
 422 }
 423
 424 ACPI_EXPORT_SYMBOL(acpi_walk_namespace)
 425
 426 /*******************************************************************************
 427  *
 428  * FUNCTION:    acpi_ns_get_device_callback
 429  *
 430  * PARAMETERS:  Callback from acpi_get_device
 431  *
 432  * RETURN:      Status
 433  *
 434  * DESCRIPTION: Takes callbacks from walk_namespace and filters out all non-
 435  *              present devices, or if they specified a HID, it filters based
 436  *              on that.
 437  *
 438  ******************************************************************************/
 439 static acpi_status
 440 acpi_ns_get_device_callback(acpi_handle obj_handle,
 441                             u32 nesting_level,
 442                             void *context, void **return_value)
 443 {
 444         struct acpi_get_devices_info *info = context;
 445         acpi_status status;
 446         struct acpi_namespace_node *node;
 447         u32 flags;
 448         struct acpi_device_id hid;
 449         struct acpi_compatible_id_list *cid;
 450         acpi_native_uint i;
 451
 452         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 453         if (ACPI_FAILURE(status)) {
 454                 return (status);
 455         }
 456
 457         node = acpi_ns_map_handle_to_node(obj_handle);
 458         status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 459         if (ACPI_FAILURE(status)) {
 460                 return (status);
 461         }
 462
 463         if (!node) {
 464                 return (AE_BAD_PARAMETER);
 465         }
 466
 467         /* Run _STA to determine if device is present */
 468
 469         status = acpi_ut_execute_STA(node, &flags);
 470         if (ACPI_FAILURE(status)) {
 471                 return (AE_CTRL_DEPTH);
 472         }
 473
 474         if (!(flags & ACPI_STA_DEVICE_PRESENT)) {
 475
 476                 /* Don't examine children of the device if not present */
 477
 478                 return (AE_CTRL_DEPTH);
 479         }
 480
 481         /* Filter based on device HID & CID */
 482
 483         if (info->hid != NULL) {
 484                 status = acpi_ut_execute_HID(node, &hid);
 485                 if (status == AE_NOT_FOUND) {
 486                         return (AE_OK);
 487                 } else if (ACPI_FAILURE(status)) {
 488                         return (AE_CTRL_DEPTH);
 489                 }
 490
 491                 if (ACPI_STRNCMP(hid.value, info->hid, sizeof(hid.value)) != 0) {
 492
 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_FREE(cid);
 510                                         return (AE_OK);
 511                                 }
 512                         }
 513                         ACPI_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.hid = HID;
 568         info.context = context;
 569         info.user_function = user_function;
 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, ACPI_ROOT_OBJECT,
 583                                         ACPI_UINT32_MAX, ACPI_NS_WALK_UNLOCK,
 584                                         acpi_ns_get_device_callback, &info,
 585                                         return_value);
 586
 587         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 588         return_ACPI_STATUS(status);
 589 }
 590
 591 ACPI_EXPORT_SYMBOL(acpi_get_devices)
 592
 593 /*******************************************************************************
 594  *
 595  * FUNCTION:    acpi_attach_data
 596  *
 597  * PARAMETERS:  obj_handle          - Namespace node
 598  *              Handler             - Handler for this attachment
 599  *              Data                - Pointer to data to be attached
 600  *
 601  * RETURN:      Status
 602  *
 603  * DESCRIPTION: Attach arbitrary data and handler to a namespace node.
 604  *
 605  ******************************************************************************/
 606 acpi_status
 607 acpi_attach_data(acpi_handle obj_handle,
 608                  acpi_object_handler handler, void *data)
 609 {
 610         struct acpi_namespace_node *node;
 611         acpi_status status;
 612
 613         /* Parameter validation */
 614
 615         if (!obj_handle || !handler || !data) {
 616                 return (AE_BAD_PARAMETER);
 617         }
 618
 619         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 620         if (ACPI_FAILURE(status)) {
 621                 return (status);
 622         }
 623
 624         /* Convert and validate the handle */
 625
 626         node = acpi_ns_map_handle_to_node(obj_handle);
 627         if (!node) {
 628                 status = AE_BAD_PARAMETER;
 629                 goto unlock_and_exit;
 630         }
 631
 632         status = acpi_ns_attach_data(node, handler, data);
 633
 634       unlock_and_exit:
 635         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 636         return (status);
 637 }
 638
 639 ACPI_EXPORT_SYMBOL(acpi_attach_data)
 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 acpi_status
 654 acpi_detach_data(acpi_handle obj_handle, acpi_object_handler handler)
 655 {
 656         struct acpi_namespace_node *node;
 657         acpi_status status;
 658
 659         /* Parameter validation */
 660
 661         if (!obj_handle || !handler) {
 662                 return (AE_BAD_PARAMETER);
 663         }
 664
 665         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 666         if (ACPI_FAILURE(status)) {
 667                 return (status);
 668         }
 669
 670         /* Convert and validate the handle */
 671
 672         node = acpi_ns_map_handle_to_node(obj_handle);
 673         if (!node) {
 674                 status = AE_BAD_PARAMETER;
 675                 goto unlock_and_exit;
 676         }
 677
 678         status = acpi_ns_detach_data(node, handler);
 679
 680       unlock_and_exit:
 681         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 682         return (status);
 683 }
 684
 685 ACPI_EXPORT_SYMBOL(acpi_detach_data)
 686
 687 /*******************************************************************************
 688  *
 689  * FUNCTION:    acpi_get_data
 690  *
 691  * PARAMETERS:  obj_handle          - Namespace node
 692  *              Handler             - Handler used in call to attach_data
 693  *              Data                - Where the data is returned
 694  *
 695  * RETURN:      Status
 696  *
 697  * DESCRIPTION: Retrieve data that was previously attached to a namespace node.
 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 }
 731
 732 ACPI_EXPORT_SYMBOL(acpi_get_data)