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         struct acpi_evaluate_info *info;
 174         acpi_size buffer_space_needed;
 175         u32 i;
 176
 177         ACPI_FUNCTION_TRACE(acpi_evaluate_object);
 178
 179         /* Allocate and initialize the evaluation information block */
 180
 181         info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
 182         if (!info) {
 183                 return_ACPI_STATUS(AE_NO_MEMORY);
 184         }
 185
 186         info->pathname = pathname;
 187         info->parameter_type = ACPI_PARAM_ARGS;
 188
 189         /* Convert and validate the device handle */
 190
 191         info->prefix_node = acpi_ns_map_handle_to_node(handle);
 192         if (!info->prefix_node) {
 193                 status = AE_BAD_PARAMETER;
 194                 goto cleanup;
 195         }
 196
 197         /*
 198          * If there are parameters to be passed to a control method, the external
 199          * objects must all be converted to internal objects
 200          */
 201         if (external_params && external_params->count) {
 202                 /*
 203                  * Allocate a new parameter block for the internal objects
 204                  * Add 1 to count to allow for null terminated internal list
 205                  */
 206                 info->parameters = ACPI_ALLOCATE_ZEROED(((acpi_size)
 207                                                          external_params->
 208                                                          count +
 209                                                          1) * sizeof(void *));
 210                 if (!info->parameters) {
 211                         status = AE_NO_MEMORY;
 212                         goto cleanup;
 213                 }
 214
 215                 /* Convert each external object in the list to an internal object */
 216
 217                 for (i = 0; i < external_params->count; i++) {
 218                         status =
 219                             acpi_ut_copy_eobject_to_iobject(&external_params->
 220                                                             pointer[i],
 221                                                             &info->
 222                                                             parameters[i]);
 223                         if (ACPI_FAILURE(status)) {
 224                                 goto cleanup;
 225                         }
 226                 }
 227                 info->parameters[external_params->count] = NULL;
 228         }
 229
 230         /*
 231          * Three major cases:
 232          * 1) Fully qualified pathname
 233          * 2) No handle, not fully qualified pathname (error)
 234          * 3) Valid handle
 235          */
 236         if ((pathname) && (acpi_ns_valid_root_prefix(pathname[0]))) {
 237
 238                 /* The path is fully qualified, just evaluate by name */
 239
 240                 info->prefix_node = NULL;
 241                 status = acpi_ns_evaluate(info);
 242         } else if (!handle) {
 243                 /*
 244                  * A handle is optional iff a fully qualified pathname is specified.
 245                  * Since we've already handled fully qualified names above, this is
 246                  * an error
 247                  */
 248                 if (!pathname) {
 249                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 250                                           "Both Handle and Pathname are NULL"));
 251                 } else {
 252                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 253                                           "Null Handle with relative pathname [%s]",
 254                                           pathname));
 255                 }
 256
 257                 status = AE_BAD_PARAMETER;
 258         } else {
 259                 /* We have a namespace a node and a possible relative path */
 260
 261                 status = acpi_ns_evaluate(info);
 262         }
 263
 264         /*
 265          * If we are expecting a return value, and all went well above,
 266          * copy the return value to an external object.
 267          */
 268         if (return_buffer) {
 269                 if (!info->return_object) {
 270                         return_buffer->length = 0;
 271                 } else {
 272                         if (ACPI_GET_DESCRIPTOR_TYPE(info->return_object) ==
 273                             ACPI_DESC_TYPE_NAMED) {
 274                                 /*
 275                                  * If we received a NS Node as a return object, this means that
 276                                  * the object we are evaluating has nothing interesting to
 277                                  * return (such as a mutex, etc.)  We return an error because
 278                                  * these types are essentially unsupported by this interface.
 279                                  * We don't check up front because this makes it easier to add
 280                                  * support for various types at a later date if necessary.
 281                                  */
 282                                 status = AE_TYPE;
 283                                 info->return_object = NULL;     /* No need to delete a NS Node */
 284                                 return_buffer->length = 0;
 285                         }
 286
 287                         if (ACPI_SUCCESS(status)) {
 288
 289                                 /* Get the size of the returned object */
 290
 291                                 status =
 292                                     acpi_ut_get_object_size(info->return_object,
 293                                                             &buffer_space_needed);
 294                                 if (ACPI_SUCCESS(status)) {
 295
 296                                         /* Validate/Allocate/Clear caller buffer */
 297
 298                                         status =
 299                                             acpi_ut_initialize_buffer
 300                                             (return_buffer,
 301                                              buffer_space_needed);
 302                                         if (ACPI_FAILURE(status)) {
 303                                                 /*
 304                                                  * Caller's buffer is too small or a new one can't
 305                                                  * be allocated
 306                                                  */
 307                                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 308                                                                   "Needed buffer size %X, %s\n",
 309                                                                   (u32)
 310                                                                   buffer_space_needed,
 311                                                                   acpi_format_exception
 312                                                                   (status)));
 313                                         } else {
 314                                                 /* We have enough space for the object, build it */
 315
 316                                                 status =
 317                                                     acpi_ut_copy_iobject_to_eobject
 318                                                     (info->return_object,
 319                                                      return_buffer);
 320                                         }
 321                                 }
 322                         }
 323                 }
 324         }
 325
 326         if (info->return_object) {
 327                 /*
 328                  * Delete the internal return object. NOTE: Interpreter must be
 329                  * locked to avoid race condition.
 330                  */
 331                 acpi_ex_enter_interpreter();
 332
 333                 /* Remove one reference on the return object (should delete it) */
 334
 335                 acpi_ut_remove_reference(info->return_object);
 336                 acpi_ex_exit_interpreter();
 337         }
 338
 339       cleanup:
 340
 341         /* Free the input parameter list (if we created one) */
 342
 343         if (info->parameters) {
 344
 345                 /* Free the allocated parameter block */
 346
 347                 acpi_ut_delete_internal_object_list(info->parameters);
 348         }
 349
 350         ACPI_FREE(info);
 351         return_ACPI_STATUS(status);
 352 }
 353
 354 ACPI_EXPORT_SYMBOL(acpi_evaluate_object)
 355
 356 /*******************************************************************************
 357  *
 358  * FUNCTION:    acpi_walk_namespace
 359  *
 360  * PARAMETERS:  Type                - acpi_object_type to search for
 361  *              start_object        - Handle in namespace where search begins
 362  *              max_depth           - Depth to which search is to reach
 363  *              user_function       - Called when an object of "Type" is found
 364  *              Context             - Passed to user function
 365  *              return_value        - Location where return value of
 366  *                                    user_function is put if terminated early
 367  *
 368  * RETURNS      Return value from the user_function if terminated early.
 369  *              Otherwise, returns NULL.
 370  *
 371  * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
 372  *              starting (and ending) at the object specified by start_handle.
 373  *              The user_function is called whenever an object that matches
 374  *              the type parameter is found.  If the user function returns
 375  *              a non-zero value, the search is terminated immediately and this
 376  *              value is returned to the caller.
 377  *
 378  *              The point of this procedure is to provide a generic namespace
 379  *              walk routine that can be called from multiple places to
 380  *              provide multiple services;  the User Function can be tailored
 381  *              to each task, whether it is a print function, a compare
 382  *              function, etc.
 383  *
 384  ******************************************************************************/
 385 acpi_status
 386 acpi_walk_namespace(acpi_object_type type,
 387                     acpi_handle start_object,
 388                     u32 max_depth,
 389                     acpi_walk_callback user_function,
 390                     void *context, void **return_value)
 391 {
 392         acpi_status status;
 393
 394         ACPI_FUNCTION_TRACE(acpi_walk_namespace);
 395
 396         /* Parameter validation */
 397
 398         if ((type > ACPI_TYPE_LOCAL_MAX) || (!max_depth) || (!user_function)) {
 399                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 400         }
 401
 402         /*
 403          * Lock the namespace around the walk.
 404          * The namespace will be unlocked/locked around each call
 405          * to the user function - since this function
 406          * must be allowed to make Acpi calls itself.
 407          */
 408         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 409         if (ACPI_FAILURE(status)) {
 410                 return_ACPI_STATUS(status);
 411         }
 412
 413         status = acpi_ns_walk_namespace(type, start_object, max_depth,
 414                                         ACPI_NS_WALK_UNLOCK,
 415                                         user_function, context, return_value);
 416
 417         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 418         return_ACPI_STATUS(status);
 419 }
 420
 421 ACPI_EXPORT_SYMBOL(acpi_walk_namespace)
 422
 423 /*******************************************************************************
 424  *
 425  * FUNCTION:    acpi_ns_get_device_callback
 426  *
 427  * PARAMETERS:  Callback from acpi_get_device
 428  *
 429  * RETURN:      Status
 430  *
 431  * DESCRIPTION: Takes callbacks from walk_namespace and filters out all non-
 432  *              present devices, or if they specified a HID, it filters based
 433  *              on that.
 434  *
 435  ******************************************************************************/
 436 static acpi_status
 437 acpi_ns_get_device_callback(acpi_handle obj_handle,
 438                             u32 nesting_level,
 439                             void *context, void **return_value)
 440 {
 441         struct acpi_get_devices_info *info = context;
 442         acpi_status status;
 443         struct acpi_namespace_node *node;
 444         u32 flags;
 445         struct acpi_device_id hid;
 446         struct acpi_compatible_id_list *cid;
 447         acpi_native_uint i;
 448
 449         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 450         if (ACPI_FAILURE(status)) {
 451                 return (status);
 452         }
 453
 454         node = acpi_ns_map_handle_to_node(obj_handle);
 455         status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 456         if (ACPI_FAILURE(status)) {
 457                 return (status);
 458         }
 459
 460         if (!node) {
 461                 return (AE_BAD_PARAMETER);
 462         }
 463
 464         /* Run _STA to determine if device is present */
 465
 466         status = acpi_ut_execute_STA(node, &flags);
 467         if (ACPI_FAILURE(status)) {
 468                 return (AE_CTRL_DEPTH);
 469         }
 470
 471         if (!(flags & ACPI_STA_DEVICE_PRESENT)) {
 472
 473                 /* Don't examine children of the device if not present */
 474
 475                 return (AE_CTRL_DEPTH);
 476         }
 477
 478         /* Filter based on device HID & CID */
 479
 480         if (info->hid != NULL) {
 481                 status = acpi_ut_execute_HID(node, &hid);
 482                 if (status == AE_NOT_FOUND) {
 483                         return (AE_OK);
 484                 } else if (ACPI_FAILURE(status)) {
 485                         return (AE_CTRL_DEPTH);
 486                 }
 487
 488                 if (ACPI_STRNCMP(hid.value, info->hid, sizeof(hid.value)) != 0) {
 489
 490                         /* Get the list of Compatible IDs */
 491
 492                         status = acpi_ut_execute_CID(node, &cid);
 493                         if (status == AE_NOT_FOUND) {
 494                                 return (AE_OK);
 495                         } else if (ACPI_FAILURE(status)) {
 496                                 return (AE_CTRL_DEPTH);
 497                         }
 498
 499                         /* Walk the CID list */
 500
 501                         for (i = 0; i < cid->count; i++) {
 502                                 if (ACPI_STRNCMP(cid->id[i].value, info->hid,
 503                                                  sizeof(struct
 504                                                         acpi_compatible_id)) !=
 505                                     0) {
 506                                         ACPI_FREE(cid);
 507                                         return (AE_OK);
 508                                 }
 509                         }
 510                         ACPI_FREE(cid);
 511                 }
 512         }
 513
 514         status = info->user_function(obj_handle, nesting_level, info->context,
 515                                      return_value);
 516         return (status);
 517 }
 518
 519 /*******************************************************************************
 520  *
 521  * FUNCTION:    acpi_get_devices
 522  *
 523  * PARAMETERS:  HID                 - HID to search for. Can be NULL.
 524  *              user_function       - Called when a matching object is found
 525  *              Context             - Passed to user function
 526  *              return_value        - Location where return value of
 527  *                                    user_function is put if terminated early
 528  *
 529  * RETURNS      Return value from the user_function if terminated early.
 530  *              Otherwise, returns NULL.
 531  *
 532  * DESCRIPTION: Performs a modified depth-first walk of the namespace tree,
 533  *              starting (and ending) at the object specified by start_handle.
 534  *              The user_function is called whenever an object of type
 535  *              Device is found.  If the user function returns
 536  *              a non-zero value, the search is terminated immediately and this
 537  *              value is returned to the caller.
 538  *
 539  *              This is a wrapper for walk_namespace, but the callback performs
 540  *              additional filtering. Please see acpi_get_device_callback.
 541  *
 542  ******************************************************************************/
 543
 544 acpi_status
 545 acpi_get_devices(char *HID,
 546                  acpi_walk_callback user_function,
 547                  void *context, void **return_value)
 548 {
 549         acpi_status status;
 550         struct acpi_get_devices_info info;
 551
 552         ACPI_FUNCTION_TRACE(acpi_get_devices);
 553
 554         /* Parameter validation */
 555
 556         if (!user_function) {
 557                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 558         }
 559
 560         /*
 561          * We're going to call their callback from OUR callback, so we need
 562          * to know what it is, and their context parameter.
 563          */
 564         info.hid = HID;
 565         info.context = context;
 566         info.user_function = user_function;
 567
 568         /*
 569          * Lock the namespace around the walk.
 570          * The namespace will be unlocked/locked around each call
 571          * to the user function - since this function
 572          * must be allowed to make Acpi calls itself.
 573          */
 574         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 575         if (ACPI_FAILURE(status)) {
 576                 return_ACPI_STATUS(status);
 577         }
 578
 579         status = acpi_ns_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
 580                                         ACPI_UINT32_MAX, ACPI_NS_WALK_UNLOCK,
 581                                         acpi_ns_get_device_callback, &info,
 582                                         return_value);
 583
 584         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 585         return_ACPI_STATUS(status);
 586 }
 587
 588 ACPI_EXPORT_SYMBOL(acpi_get_devices)
 589
 590 /*******************************************************************************
 591  *
 592  * FUNCTION:    acpi_attach_data
 593  *
 594  * PARAMETERS:  obj_handle          - Namespace node
 595  *              Handler             - Handler for this attachment
 596  *              Data                - Pointer to data to be attached
 597  *
 598  * RETURN:      Status
 599  *
 600  * DESCRIPTION: Attach arbitrary data and handler to a namespace node.
 601  *
 602  ******************************************************************************/
 603 acpi_status
 604 acpi_attach_data(acpi_handle obj_handle,
 605                  acpi_object_handler handler, void *data)
 606 {
 607         struct acpi_namespace_node *node;
 608         acpi_status status;
 609
 610         /* Parameter validation */
 611
 612         if (!obj_handle || !handler || !data) {
 613                 return (AE_BAD_PARAMETER);
 614         }
 615
 616         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 617         if (ACPI_FAILURE(status)) {
 618                 return (status);
 619         }
 620
 621         /* Convert and validate the handle */
 622
 623         node = acpi_ns_map_handle_to_node(obj_handle);
 624         if (!node) {
 625                 status = AE_BAD_PARAMETER;
 626                 goto unlock_and_exit;
 627         }
 628
 629         status = acpi_ns_attach_data(node, handler, data);
 630
 631       unlock_and_exit:
 632         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 633         return (status);
 634 }
 635
 636 ACPI_EXPORT_SYMBOL(acpi_attach_data)
 637
 638 /*******************************************************************************
 639  *
 640  * FUNCTION:    acpi_detach_data
 641  *
 642  * PARAMETERS:  obj_handle          - Namespace node handle
 643  *              Handler             - Handler used in call to acpi_attach_data
 644  *
 645  * RETURN:      Status
 646  *
 647  * DESCRIPTION: Remove data that was previously attached to a node.
 648  *
 649  ******************************************************************************/
 650 acpi_status
 651 acpi_detach_data(acpi_handle obj_handle, acpi_object_handler handler)
 652 {
 653         struct acpi_namespace_node *node;
 654         acpi_status status;
 655
 656         /* Parameter validation */
 657
 658         if (!obj_handle || !handler) {
 659                 return (AE_BAD_PARAMETER);
 660         }
 661
 662         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 663         if (ACPI_FAILURE(status)) {
 664                 return (status);
 665         }
 666
 667         /* Convert and validate the handle */
 668
 669         node = acpi_ns_map_handle_to_node(obj_handle);
 670         if (!node) {
 671                 status = AE_BAD_PARAMETER;
 672                 goto unlock_and_exit;
 673         }
 674
 675         status = acpi_ns_detach_data(node, handler);
 676
 677       unlock_and_exit:
 678         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 679         return (status);
 680 }
 681
 682 ACPI_EXPORT_SYMBOL(acpi_detach_data)
 683
 684 /*******************************************************************************
 685  *
 686  * FUNCTION:    acpi_get_data
 687  *
 688  * PARAMETERS:  obj_handle          - Namespace node
 689  *              Handler             - Handler used in call to attach_data
 690  *              Data                - Where the data is returned
 691  *
 692  * RETURN:      Status
 693  *
 694  * DESCRIPTION: Retrieve data that was previously attached to a namespace node.
 695  *
 696  ******************************************************************************/
 697 acpi_status
 698 acpi_get_data(acpi_handle obj_handle, acpi_object_handler handler, void **data)
 699 {
 700         struct acpi_namespace_node *node;
 701         acpi_status status;
 702
 703         /* Parameter validation */
 704
 705         if (!obj_handle || !handler || !data) {
 706                 return (AE_BAD_PARAMETER);
 707         }
 708
 709         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
 710         if (ACPI_FAILURE(status)) {
 711                 return (status);
 712         }
 713
 714         /* Convert and validate the handle */
 715
 716         node = acpi_ns_map_handle_to_node(obj_handle);
 717         if (!node) {
 718                 status = AE_BAD_PARAMETER;
 719                 goto unlock_and_exit;
 720         }
 721
 722         status = acpi_ns_get_attached_data(node, handler, data);
 723
 724       unlock_and_exit:
 725         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
 726         return (status);
 727 }
 728
 729 ACPI_EXPORT_SYMBOL(acpi_get_data)