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
 186         /* Convert and validate the device handle */
 187
 188         info->prefix_node = acpi_ns_map_handle_to_node(handle);
 189         if (!info->prefix_node) {
 190                 status = AE_BAD_PARAMETER;
 191                 goto cleanup;
 192         }
 193
 194         /*
 195          * If there are parameters to be passed to a control method, the external
 196          * objects must all be converted to internal objects
 197          */
 198         if (external_params && external_params->count) {
 199                 /*
 200                  * Allocate a new parameter block for the internal objects
 201                  * Add 1 to count to allow for null terminated internal list
 202                  */
 203                 info->parameters = ACPI_ALLOCATE_ZEROED(((acpi_size)
 204                                                          external_params->
 205                                                          count +
 206                                                          1) * sizeof(void *));
 207                 if (!info->parameters) {
 208                         status = AE_NO_MEMORY;
 209                         goto cleanup;
 210                 }
 211
 212                 /* Convert each external object in the list to an internal object */
 213
 214                 for (i = 0; i < external_params->count; i++) {
 215                         status =
 216                             acpi_ut_copy_eobject_to_iobject(&external_params->
 217                                                             pointer[i],
 218                                                             &info->
 219                                                             parameters[i]);
 220                         if (ACPI_FAILURE(status)) {
 221                                 goto cleanup;
 222                         }
 223                 }
 224                 info->parameters[external_params->count] = NULL;
 225         }
 226
 227         /*
 228          * Three major cases:
 229          * 1) Fully qualified pathname
 230          * 2) No handle, not fully qualified pathname (error)
 231          * 3) Valid handle
 232          */
 233         if ((pathname) && (acpi_ns_valid_root_prefix(pathname[0]))) {
 234
 235                 /* The path is fully qualified, just evaluate by name */
 236
 237                 info->prefix_node = NULL;
 238                 status = acpi_ns_evaluate(info);
 239         } else if (!handle) {
 240                 /*
 241                  * A handle is optional iff a fully qualified pathname is specified.
 242                  * Since we've already handled fully qualified names above, this is
 243                  * an error
 244                  */
 245                 if (!pathname) {
 246                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 247                                           "Both Handle and Pathname are NULL"));
 248                 } else {
 249                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 250                                           "Null Handle with relative pathname [%s]",
 251                                           pathname));
 252                 }
 253
 254                 status = AE_BAD_PARAMETER;
 255         } else {
 256                 /* We have a namespace a node and a possible relative path */
 257
 258                 status = acpi_ns_evaluate(info);
 259         }
 260
 261         /*
 262          * If we are expecting a return value, and all went well above,
 263          * copy the return value to an external object.
 264          */
 265         if (return_buffer) {
 266                 if (!info->return_object) {
 267                         return_buffer->length = 0;
 268                 } else {
 269                         if (ACPI_GET_DESCRIPTOR_TYPE(info->return_object) ==
 270                             ACPI_DESC_TYPE_NAMED) {
 271                                 /*
 272                                  * If we received a NS Node as a return object, this means that
 273                                  * the object we are evaluating has nothing interesting to
 274                                  * return (such as a mutex, etc.)  We return an error because
 275                                  * these types are essentially unsupported by this interface.
 276                                  * We don't check up front because this makes it easier to add
 277                                  * support for various types at a later date if necessary.
 278                                  */
 279                                 status = AE_TYPE;
 280                                 info->return_object = NULL;     /* No need to delete a NS Node */
 281                                 return_buffer->length = 0;
 282                         }
 283
 284                         if (ACPI_SUCCESS(status)) {
 285
 286                                 /* Get the size of the returned object */
 287
 288                                 status =
 289                                     acpi_ut_get_object_size(info->return_object,
 290                                                             &buffer_space_needed);
 291                                 if (ACPI_SUCCESS(status)) {
 292
 293                                         /* Validate/Allocate/Clear caller buffer */
 294
 295                                         status =
 296                                             acpi_ut_initialize_buffer
 297                                             (return_buffer,
 298                                              buffer_space_needed);
 299                                         if (ACPI_FAILURE(status)) {
 300                                                 /*
 301                                                  * Caller's buffer is too small or a new one can't
 302                                                  * be allocated
 303                                                  */
 304                                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 305                                                                   "Needed buffer size %X, %s\n",
 306                                                                   (u32)
 307                                                                   buffer_space_needed,
 308                                                                   acpi_format_exception
 309                                                                   (status)));
 310                                         } else {
 311                                                 /* We have enough space for the object, build it */
 312
 313                                                 status =
 314                                                     acpi_ut_copy_iobject_to_eobject
 315                                                     (info->return_object,
 316                                                      return_buffer);
 317                                         }
 318                                 }
 319                         }
 320                 }
 321         }
 322
 323         if (info->return_object) {
 324                 /*
 325                  * Delete the internal return object. NOTE: Interpreter must be
 326                  * locked to avoid race condition.
 327                  */
 328                 acpi_ex_enter_interpreter();
 329
 330                 /* Remove one reference on the return object (should delete it) */
 331
 332                 acpi_ut_remove_reference(info->return_object);
 333                 acpi_ex_exit_interpreter();
 334         }
 335
 336       cleanup:
 337
 338         /* Free the input parameter list (if we created one) */
 339
 340         if (info->parameters) {
 341
 342                 /* Free the allocated parameter block */
 343
 344                 acpi_ut_delete_internal_object_list(info->parameters);
 345         }
 346
 347         ACPI_FREE(info);
 348         return_ACPI_STATUS(status);
 349 }
 350
 351 ACPI_EXPORT_SYMBOL(acpi_evaluate_object)
 352
 353 /*******************************************************************************
 354  *
 355  * FUNCTION:    acpi_walk_namespace
 356  *
 357  * PARAMETERS:  Type                - acpi_object_type to search for
 358  *              start_object        - Handle in namespace where search begins
 359  *              max_depth           - Depth to which search is to reach
 360  *              user_function       - Called when an object of "Type" is found
 361  *              Context             - Passed to user function
 362  *              return_value        - Location where return value of
 363  *                                    user_function is put if terminated early
 364  *
 365  * RETURNS      Return value from the user_function if terminated early.
 366  *              Otherwise, returns NULL.
 367  *
 368  * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
 369  *              starting (and ending) at the object specified by start_handle.
 370  *              The user_function is called whenever an object that matches
 371  *              the type parameter is found.  If the user function returns
 372  *              a non-zero value, the search is terminated immediately and this
 373  *              value is returned to the caller.
 374  *
 375  *              The point of this procedure is to provide a generic namespace
 376  *              walk routine that can be called from multiple places to
 377  *              provide multiple services;  the User Function can be tailored
 378  *              to each task, whether it is a print function, a compare
 379  *              function, etc.
 380  *
 381  ******************************************************************************/
 382 acpi_status
 383 acpi_walk_namespace(acpi_object_type type,
 384                     acpi_handle start_object,
 385                     u32 max_depth,
 386                     acpi_walk_callback user_function,
 387                     void *context, void **return_value)
 388 {
 389         acpi_status status;
 390
 391         ACPI_FUNCTION_TRACE(acpi_walk_namespace);
 392
 393         /* Parameter validation */
 394
 395         if ((type > ACPI_TYPE_LOCAL_MAX) || (!max_depth) || (!user_function)) {
 396                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 397         }
 398
 399         /*
 400          * Lock the namespace around the walk.
 401          * The namespace will be unlocked/locked around each call
 402          * to the user function - since this function
 403          * must be allowed to make Acpi calls itself.
 404          */
 405         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 406         if (ACPI_FAILURE(status)) {
 407                 return_ACPI_STATUS(status);
 408         }
 409
 410         status = acpi_ns_walk_namespace(type, start_object, max_depth,
 411                                         ACPI_NS_WALK_UNLOCK,
 412                                         user_function, context, return_value);
 413
 414         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 415         return_ACPI_STATUS(status);
 416 }
 417
 418 ACPI_EXPORT_SYMBOL(acpi_walk_namespace)
 419
 420 /*******************************************************************************
 421  *
 422  * FUNCTION:    acpi_ns_get_device_callback
 423  *
 424  * PARAMETERS:  Callback from acpi_get_device
 425  *
 426  * RETURN:      Status
 427  *
 428  * DESCRIPTION: Takes callbacks from walk_namespace and filters out all non-
 429  *              present devices, or if they specified a HID, it filters based
 430  *              on that.
 431  *
 432  ******************************************************************************/
 433 static acpi_status
 434 acpi_ns_get_device_callback(acpi_handle obj_handle,
 435                             u32 nesting_level,
 436                             void *context, void **return_value)
 437 {
 438         struct acpi_get_devices_info *info = context;
 439         acpi_status status;
 440         struct acpi_namespace_node *node;
 441         u32 flags;
 442         struct acpica_device_id hid;
 443         struct acpi_compatible_id_list *cid;
 444         u32 i;
 445         int found;
 446
 447         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 448         if (ACPI_FAILURE(status)) {
 449                 return (status);
 450         }
 451
 452         node = acpi_ns_map_handle_to_node(obj_handle);
 453         status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 454         if (ACPI_FAILURE(status)) {
 455                 return (status);
 456         }
 457
 458         if (!node) {
 459                 return (AE_BAD_PARAMETER);
 460         }
 461
 462         /* Run _STA to determine if device is present */
 463
 464         status = acpi_ut_execute_STA(node, &flags);
 465         if (ACPI_FAILURE(status)) {
 466                 return (AE_CTRL_DEPTH);
 467         }
 468
 469         if (!(flags & ACPI_STA_DEVICE_PRESENT) &&
 470             !(flags & ACPI_STA_DEVICE_FUNCTIONING)) {
 471                 /*
 472                  * Don't examine the children of the device only when the
 473                  * device is neither present nor functional. See ACPI spec,
 474                  * description of _STA for more information.
 475                  */
 476                 return (AE_CTRL_DEPTH);
 477         }
 478
 479         /* Filter based on device HID & CID */
 480
 481         if (info->hid != NULL) {
 482                 status = acpi_ut_execute_HID(node, &hid);
 483                 if (status == AE_NOT_FOUND) {
 484                         return (AE_OK);
 485                 } else if (ACPI_FAILURE(status)) {
 486                         return (AE_CTRL_DEPTH);
 487                 }
 488
 489                 if (ACPI_STRNCMP(hid.value, info->hid, sizeof(hid.value)) != 0) {
 490
 491                         /* Get the list of Compatible IDs */
 492
 493                         status = acpi_ut_execute_CID(node, &cid);
 494                         if (status == AE_NOT_FOUND) {
 495                                 return (AE_OK);
 496                         } else if (ACPI_FAILURE(status)) {
 497                                 return (AE_CTRL_DEPTH);
 498                         }
 499
 500                         /* Walk the CID list */
 501
 502                         found = 0;
 503                         for (i = 0; i < cid->count; i++) {
 504                                 if (ACPI_STRNCMP(cid->id[i].value, info->hid,
 505                                                  sizeof(struct
 506                                                         acpi_compatible_id)) ==
 507                                     0) {
 508                                         found = 1;
 509                                         break;
 510                                 }
 511                         }
 512                         ACPI_FREE(cid);
 513                         if (!found)
 514                                 return (AE_OK);
 515                 }
 516         }
 517
 518         status = info->user_function(obj_handle, nesting_level, info->context,
 519                                      return_value);
 520         return (status);
 521 }
 522
 523 /*******************************************************************************
 524  *
 525  * FUNCTION:    acpi_get_devices
 526  *
 527  * PARAMETERS:  HID                 - HID to search for. Can be NULL.
 528  *              user_function       - Called when a matching object is found
 529  *              Context             - Passed to user function
 530  *              return_value        - Location where return value of
 531  *                                    user_function is put if terminated early
 532  *
 533  * RETURNS      Return value from the user_function if terminated early.
 534  *              Otherwise, returns NULL.
 535  *
 536  * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
 537  *              starting (and ending) at the object specified by start_handle.
 538  *              The user_function is called whenever an object of type
 539  *              Device is found.  If the user function returns
 540  *              a non-zero value, the search is terminated immediately and this
 541  *              value is returned to the caller.
 542  *
 543  *              This is a wrapper for walk_namespace, but the callback performs
 544  *              additional filtering. Please see acpi_ns_get_device_callback.
 545  *
 546  ******************************************************************************/
 547
 548 acpi_status
 549 acpi_get_devices(const char *HID,
 550                  acpi_walk_callback user_function,
 551                  void *context, void **return_value)
 552 {
 553         acpi_status status;
 554         struct acpi_get_devices_info info;
 555
 556         ACPI_FUNCTION_TRACE(acpi_get_devices);
 557
 558         /* Parameter validation */
 559
 560         if (!user_function) {
 561                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 562         }
 563
 564         /*
 565          * We're going to call their callback from OUR callback, so we need
 566          * to know what it is, and their context parameter.
 567          */
 568         info.hid = HID;
 569         info.context = context;
 570         info.user_function = user_function;
 571
 572         /*
 573          * Lock the namespace around the walk.
 574          * The namespace will be unlocked/locked around each call
 575          * to the user function - since this function
 576          * must be allowed to make Acpi calls itself.
 577          */
 578         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 579         if (ACPI_FAILURE(status)) {
 580                 return_ACPI_STATUS(status);
 581         }
 582
 583         status = acpi_ns_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
 584                                         ACPI_UINT32_MAX, ACPI_NS_WALK_UNLOCK,
 585                                         acpi_ns_get_device_callback, &info,
 586                                         return_value);
 587
 588         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 589         return_ACPI_STATUS(status);
 590 }
 591
 592 ACPI_EXPORT_SYMBOL(acpi_get_devices)
 593
 594 /*******************************************************************************
 595  *
 596  * FUNCTION:    acpi_attach_data
 597  *
 598  * PARAMETERS:  obj_handle          - Namespace node
 599  *              Handler             - Handler for this attachment
 600  *              Data                - Pointer to data to be attached
 601  *
 602  * RETURN:      Status
 603  *
 604  * DESCRIPTION: Attach arbitrary data and handler to a namespace node.
 605  *
 606  ******************************************************************************/
 607 acpi_status
 608 acpi_attach_data(acpi_handle obj_handle,
 609                  acpi_object_handler handler, void *data)
 610 {
 611         struct acpi_namespace_node *node;
 612         acpi_status status;
 613
 614         /* Parameter validation */
 615
 616         if (!obj_handle || !handler || !data) {
 617                 return (AE_BAD_PARAMETER);
 618         }
 619
 620         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 621         if (ACPI_FAILURE(status)) {
 622                 return (status);
 623         }
 624
 625         /* Convert and validate the handle */
 626
 627         node = acpi_ns_map_handle_to_node(obj_handle);
 628         if (!node) {
 629                 status = AE_BAD_PARAMETER;
 630                 goto unlock_and_exit;
 631         }
 632
 633         status = acpi_ns_attach_data(node, handler, data);
 634
 635       unlock_and_exit:
 636         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 637         return (status);
 638 }
 639
 640 ACPI_EXPORT_SYMBOL(acpi_attach_data)
 641
 642 /*******************************************************************************
 643  *
 644  * FUNCTION:    acpi_detach_data
 645  *
 646  * PARAMETERS:  obj_handle          - Namespace node handle
 647  *              Handler             - Handler used in call to acpi_attach_data
 648  *
 649  * RETURN:      Status
 650  *
 651  * DESCRIPTION: Remove data that was previously attached to a node.
 652  *
 653  ******************************************************************************/
 654 acpi_status
 655 acpi_detach_data(acpi_handle obj_handle, acpi_object_handler handler)
 656 {
 657         struct acpi_namespace_node *node;
 658         acpi_status status;
 659
 660         /* Parameter validation */
 661
 662         if (!obj_handle || !handler) {
 663                 return (AE_BAD_PARAMETER);
 664         }
 665
 666         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 667         if (ACPI_FAILURE(status)) {
 668                 return (status);
 669         }
 670
 671         /* Convert and validate the handle */
 672
 673         node = acpi_ns_map_handle_to_node(obj_handle);
 674         if (!node) {
 675                 status = AE_BAD_PARAMETER;
 676                 goto unlock_and_exit;
 677         }
 678
 679         status = acpi_ns_detach_data(node, handler);
 680
 681       unlock_and_exit:
 682         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 683         return (status);
 684 }
 685
 686 ACPI_EXPORT_SYMBOL(acpi_detach_data)
 687
 688 /*******************************************************************************
 689  *
 690  * FUNCTION:    acpi_get_data
 691  *
 692  * PARAMETERS:  obj_handle          - Namespace node
 693  *              Handler             - Handler used in call to attach_data
 694  *              Data                - Where the data is returned
 695  *
 696  * RETURN:      Status
 697  *
 698  * DESCRIPTION: Retrieve data that was previously attached to a namespace node.
 699  *
 700  ******************************************************************************/
 701 acpi_status
 702 acpi_get_data(acpi_handle obj_handle, acpi_object_handler handler, void **data)
 703 {
 704         struct acpi_namespace_node *node;
 705         acpi_status status;
 706
 707         /* Parameter validation */
 708
 709         if (!obj_handle || !handler || !data) {
 710                 return (AE_BAD_PARAMETER);
 711         }
 712
 713         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 714         if (ACPI_FAILURE(status)) {
 715                 return (status);
 716         }
 717
 718         /* Convert and validate the handle */
 719
 720         node = acpi_ns_map_handle_to_node(obj_handle);
 721         if (!node) {
 722                 status = AE_BAD_PARAMETER;
 723                 goto unlock_and_exit;
 724         }
 725
 726         status = acpi_ns_get_attached_data(node, handler, data);
 727
 728       unlock_and_exit:
 729         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 730         return (status);
 731 }
 732
 733 ACPI_EXPORT_SYMBOL(acpi_get_data)