drivers/acpi/namespace/nsxfeval.c

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