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   1 /******************************************************************************
   2  *
   3  * Module Name: nsrepair2 - Repair for objects returned by specific
   4  *                          predefined methods
   5  *
   6  *****************************************************************************/
   7
   8 /*
   9  * Copyright (C) 2000 - 2009, 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 "accommon.h"
  47 #include "acnamesp.h"
  48 #include "acpredef.h"
  49
  50 #define _COMPONENT          ACPI_NAMESPACE
  51 ACPI_MODULE_NAME("nsrepair2")
  52
  53 /*
  54  * Information structure and handler for ACPI predefined names that can
  55  * be repaired on a per-name basis.
  56  */
  57 typedef
  58 acpi_status(*acpi_repair_function) (struct acpi_predefined_data *data,
  59                                     union acpi_operand_object **return_object_ptr);
  60
  61 typedef struct acpi_repair_info {
  62         char name[ACPI_NAME_SIZE];
  63         acpi_repair_function repair_function;
  64
  65 } acpi_repair_info;
  66
  67 /* Local prototypes */
  68
  69 static const struct acpi_repair_info *acpi_ns_match_repairable_name(struct
  70                                                                     acpi_namespace_node
  71                                                                     *node);
  72
  73 static acpi_status
  74 acpi_ns_repair_ALR(struct acpi_predefined_data *data,
  75                    union acpi_operand_object **return_object_ptr);
  76
  77 static acpi_status
  78 acpi_ns_repair_FDE(struct acpi_predefined_data *data,
  79                    union acpi_operand_object **return_object_ptr);
  80
  81 static acpi_status
  82 acpi_ns_repair_PSS(struct acpi_predefined_data *data,
  83                    union acpi_operand_object **return_object_ptr);
  84
  85 static acpi_status
  86 acpi_ns_repair_TSS(struct acpi_predefined_data *data,
  87                    union acpi_operand_object **return_object_ptr);
  88
  89 static acpi_status
  90 acpi_ns_check_sorted_list(struct acpi_predefined_data *data,
  91                           union acpi_operand_object *return_object,
  92                           u32 expected_count,
  93                           u32 sort_index,
  94                           u8 sort_direction, char *sort_key_name);
  95
  96 static acpi_status
  97 acpi_ns_sort_list(union acpi_operand_object **elements,
  98                   u32 count, u32 index, u8 sort_direction);
  99
 100 /* Values for sort_direction above */
 101
 102 #define ACPI_SORT_ASCENDING     0
 103 #define ACPI_SORT_DESCENDING    1
 104
 105 /*
 106  * This table contains the names of the predefined methods for which we can
 107  * perform more complex repairs.
 108  *
 109  * As necessary:
 110  *
 111  * _ALR: Sort the list ascending by ambient_illuminance
 112  * _FDE: Convert Buffer of BYTEs to a Buffer of DWORDs
 113  * _GTM: Convert Buffer of BYTEs to a Buffer of DWORDs
 114  * _PSS: Sort the list descending by Power
 115  * _TSS: Sort the list descending by Power
 116  */
 117 static const struct acpi_repair_info acpi_ns_repairable_names[] = {
 118         {"_ALR", acpi_ns_repair_ALR},
 119         {"_FDE", acpi_ns_repair_FDE},
 120         {"_GTM", acpi_ns_repair_FDE},   /* _GTM has same repair as _FDE */
 121         {"_PSS", acpi_ns_repair_PSS},
 122         {"_TSS", acpi_ns_repair_TSS},
 123         {{0, 0, 0, 0}, NULL}    /* Table terminator */
 124 };
 125
 126 #define ACPI_FDE_FIELD_COUNT        5
 127 #define ACPI_FDE_BYTE_BUFFER_SIZE   5
 128 #define ACPI_FDE_DWORD_BUFFER_SIZE  (ACPI_FDE_FIELD_COUNT * sizeof (u32))
 129
 130 /******************************************************************************
 131  *
 132  * FUNCTION:    acpi_ns_complex_repairs
 133  *
 134  * PARAMETERS:  Data                - Pointer to validation data structure
 135  *              Node                - Namespace node for the method/object
 136  *              validate_status     - Original status of earlier validation
 137  *              return_object_ptr   - Pointer to the object returned from the
 138  *                                    evaluation of a method or object
 139  *
 140  * RETURN:      Status. AE_OK if repair was successful. If name is not
 141  *              matched, validate_status is returned.
 142  *
 143  * DESCRIPTION: Attempt to repair/convert a return object of a type that was
 144  *              not expected.
 145  *
 146  *****************************************************************************/
 147
 148 acpi_status
 149 acpi_ns_complex_repairs(struct acpi_predefined_data *data,
 150                         struct acpi_namespace_node *node,
 151                         acpi_status validate_status,
 152                         union acpi_operand_object **return_object_ptr)
 153 {
 154         const struct acpi_repair_info *predefined;
 155         acpi_status status;
 156
 157         /* Check if this name is in the list of repairable names */
 158
 159         predefined = acpi_ns_match_repairable_name(node);
 160         if (!predefined) {
 161                 return (validate_status);
 162         }
 163
 164         status = predefined->repair_function(data, return_object_ptr);
 165         return (status);
 166 }
 167
 168 /******************************************************************************
 169  *
 170  * FUNCTION:    acpi_ns_match_repairable_name
 171  *
 172  * PARAMETERS:  Node                - Namespace node for the method/object
 173  *
 174  * RETURN:      Pointer to entry in repair table. NULL indicates not found.
 175  *
 176  * DESCRIPTION: Check an object name against the repairable object list.
 177  *
 178  *****************************************************************************/
 179
 180 static const struct acpi_repair_info *acpi_ns_match_repairable_name(struct
 181                                                                     acpi_namespace_node
 182                                                                     *node)
 183 {
 184         const struct acpi_repair_info *this_name;
 185
 186         /* Search info table for a repairable predefined method/object name */
 187
 188         this_name = acpi_ns_repairable_names;
 189         while (this_name->repair_function) {
 190                 if (ACPI_COMPARE_NAME(node->name.ascii, this_name->name)) {
 191                         return (this_name);
 192                 }
 193                 this_name++;
 194         }
 195
 196         return (NULL);          /* Not found */
 197 }
 198
 199 /******************************************************************************
 200  *
 201  * FUNCTION:    acpi_ns_repair_ALR
 202  *
 203  * PARAMETERS:  Data                - Pointer to validation data structure
 204  *              return_object_ptr   - Pointer to the object returned from the
 205  *                                    evaluation of a method or object
 206  *
 207  * RETURN:      Status. AE_OK if object is OK or was repaired successfully
 208  *
 209  * DESCRIPTION: Repair for the _ALR object. If necessary, sort the object list
 210  *              ascending by the ambient illuminance values.
 211  *
 212  *****************************************************************************/
 213
 214 static acpi_status
 215 acpi_ns_repair_ALR(struct acpi_predefined_data *data,
 216                    union acpi_operand_object **return_object_ptr)
 217 {
 218         union acpi_operand_object *return_object = *return_object_ptr;
 219         acpi_status status;
 220
 221         status = acpi_ns_check_sorted_list(data, return_object, 2, 1,
 222                                            ACPI_SORT_ASCENDING,
 223                                            "AmbientIlluminance");
 224
 225         return (status);
 226 }
 227
 228 /******************************************************************************
 229  *
 230  * FUNCTION:    acpi_ns_repair_FDE
 231  *
 232  * PARAMETERS:  Data                - Pointer to validation data structure
 233  *              return_object_ptr   - Pointer to the object returned from the
 234  *                                    evaluation of a method or object
 235  *
 236  * RETURN:      Status. AE_OK if object is OK or was repaired successfully
 237  *
 238  * DESCRIPTION: Repair for the _FDE and _GTM objects. The expected return
 239  *              value is a Buffer of 5 DWORDs. This function repairs a common
 240  *              problem where the return value is a Buffer of BYTEs, not
 241  *              DWORDs.
 242  *
 243  *****************************************************************************/
 244
 245 static acpi_status
 246 acpi_ns_repair_FDE(struct acpi_predefined_data *data,
 247                    union acpi_operand_object **return_object_ptr)
 248 {
 249         union acpi_operand_object *return_object = *return_object_ptr;
 250         union acpi_operand_object *buffer_object;
 251         u8 *byte_buffer;
 252         u32 *dword_buffer;
 253         u32 i;
 254
 255         ACPI_FUNCTION_NAME(ns_repair_FDE);
 256
 257         switch (return_object->common.type) {
 258         case ACPI_TYPE_BUFFER:
 259
 260                 /* This is the expected type. Length should be (at least) 5 DWORDs */
 261
 262                 if (return_object->buffer.length >= ACPI_FDE_DWORD_BUFFER_SIZE) {
 263                         return (AE_OK);
 264                 }
 265
 266                 /* We can only repair if we have exactly 5 BYTEs */
 267
 268                 if (return_object->buffer.length != ACPI_FDE_BYTE_BUFFER_SIZE) {
 269                         ACPI_WARN_PREDEFINED((AE_INFO, data->pathname,
 270                                               data->node_flags,
 271                                               "Incorrect return buffer length %u, expected %u",
 272                                               return_object->buffer.length,
 273                                               ACPI_FDE_DWORD_BUFFER_SIZE));
 274
 275                         return (AE_AML_OPERAND_TYPE);
 276                 }
 277
 278                 /* Create the new (larger) buffer object */
 279
 280                 buffer_object =
 281                     acpi_ut_create_buffer_object(ACPI_FDE_DWORD_BUFFER_SIZE);
 282                 if (!buffer_object) {
 283                         return (AE_NO_MEMORY);
 284                 }
 285
 286                 /* Expand each byte to a DWORD */
 287
 288                 byte_buffer = return_object->buffer.pointer;
 289                 dword_buffer =
 290                     ACPI_CAST_PTR(u32, buffer_object->buffer.pointer);
 291
 292                 for (i = 0; i < ACPI_FDE_FIELD_COUNT; i++) {
 293                         *dword_buffer = (u32) *byte_buffer;
 294                         dword_buffer++;
 295                         byte_buffer++;
 296                 }
 297
 298                 ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
 299                                   "%s Expanded Byte Buffer to expected DWord Buffer\n",
 300                                   data->pathname));
 301                 break;
 302
 303         default:
 304                 return (AE_AML_OPERAND_TYPE);
 305         }
 306
 307         /* Delete the original return object, return the new buffer object */
 308
 309         acpi_ut_remove_reference(return_object);
 310         *return_object_ptr = buffer_object;
 311
 312         data->flags |= ACPI_OBJECT_REPAIRED;
 313         return (AE_OK);
 314 }
 315
 316 /******************************************************************************
 317  *
 318  * FUNCTION:    acpi_ns_repair_TSS
 319  *
 320  * PARAMETERS:  Data                - Pointer to validation data structure
 321  *              return_object_ptr   - Pointer to the object returned from the
 322  *                                    evaluation of a method or object
 323  *
 324  * RETURN:      Status. AE_OK if object is OK or was repaired successfully
 325  *
 326  * DESCRIPTION: Repair for the _TSS object. If necessary, sort the object list
 327  *              descending by the power dissipation values.
 328  *
 329  *****************************************************************************/
 330
 331 static acpi_status
 332 acpi_ns_repair_TSS(struct acpi_predefined_data *data,
 333                    union acpi_operand_object **return_object_ptr)
 334 {
 335         union acpi_operand_object *return_object = *return_object_ptr;
 336         acpi_status status;
 337
 338         status = acpi_ns_check_sorted_list(data, return_object, 5, 1,
 339                                            ACPI_SORT_DESCENDING,
 340                                            "PowerDissipation");
 341
 342         return (status);
 343 }
 344
 345 /******************************************************************************
 346  *
 347  * FUNCTION:    acpi_ns_repair_PSS
 348  *
 349  * PARAMETERS:  Data                - Pointer to validation data structure
 350  *              return_object_ptr   - Pointer to the object returned from the
 351  *                                    evaluation of a method or object
 352  *
 353  * RETURN:      Status. AE_OK if object is OK or was repaired successfully
 354  *
 355  * DESCRIPTION: Repair for the _PSS object. If necessary, sort the object list
 356  *              by the CPU frequencies. Check that the power dissipation values
 357  *              are all proportional to CPU frequency (i.e., sorting by
 358  *              frequency should be the same as sorting by power.)
 359  *
 360  *****************************************************************************/
 361
 362 static acpi_status
 363 acpi_ns_repair_PSS(struct acpi_predefined_data *data,
 364                    union acpi_operand_object **return_object_ptr)
 365 {
 366         union acpi_operand_object *return_object = *return_object_ptr;
 367         union acpi_operand_object **outer_elements;
 368         u32 outer_element_count;
 369         union acpi_operand_object **elements;
 370         union acpi_operand_object *obj_desc;
 371         u32 previous_value;
 372         acpi_status status;
 373         u32 i;
 374
 375         /*
 376          * Entries (sub-packages) in the _PSS Package must be sorted by power
 377          * dissipation, in descending order. If it appears that the list is
 378          * incorrectly sorted, sort it. We sort by cpu_frequency, since this
 379          * should be proportional to the power.
 380          */
 381         status = acpi_ns_check_sorted_list(data, return_object, 6, 0,
 382                                            ACPI_SORT_DESCENDING,
 383                                            "CpuFrequency");
 384         if (ACPI_FAILURE(status)) {
 385                 return (status);
 386         }
 387
 388         /*
 389          * We now know the list is correctly sorted by CPU frequency. Check if
 390          * the power dissipation values are proportional.
 391          */
 392         previous_value = ACPI_UINT32_MAX;
 393         outer_elements = return_object->package.elements;
 394         outer_element_count = return_object->package.count;
 395
 396         for (i = 0; i < outer_element_count; i++) {
 397                 elements = (*outer_elements)->package.elements;
 398                 obj_desc = elements[1]; /* Index1 = power_dissipation */
 399
 400                 if ((u32) obj_desc->integer.value > previous_value) {
 401                         ACPI_WARN_PREDEFINED((AE_INFO, data->pathname,
 402                                               data->node_flags,
 403                                               "SubPackage[%u,%u] - suspicious power dissipation values",
 404                                               i - 1, i));
 405                 }
 406
 407                 previous_value = (u32) obj_desc->integer.value;
 408                 outer_elements++;
 409         }
 410
 411         return (AE_OK);
 412 }
 413
 414 /******************************************************************************
 415  *
 416  * FUNCTION:    acpi_ns_check_sorted_list
 417  *
 418  * PARAMETERS:  Data                - Pointer to validation data structure
 419  *              return_object       - Pointer to the top-level returned object
 420  *              expected_count      - Minimum length of each sub-package
 421  *              sort_index          - Sub-package entry to sort on
 422  *              sort_direction      - Ascending or descending
 423  *              sort_key_name       - Name of the sort_index field
 424  *
 425  * RETURN:      Status. AE_OK if the list is valid and is sorted correctly or
 426  *              has been repaired by sorting the list.
 427  *
 428  * DESCRIPTION: Check if the package list is valid and sorted correctly by the
 429  *              sort_index. If not, then sort the list.
 430  *
 431  *****************************************************************************/
 432
 433 static acpi_status
 434 acpi_ns_check_sorted_list(struct acpi_predefined_data *data,
 435                           union acpi_operand_object *return_object,
 436                           u32 expected_count,
 437                           u32 sort_index,
 438                           u8 sort_direction, char *sort_key_name)
 439 {
 440         u32 outer_element_count;
 441         union acpi_operand_object **outer_elements;
 442         union acpi_operand_object **elements;
 443         union acpi_operand_object *obj_desc;
 444         u32 i;
 445         u32 previous_value;
 446         acpi_status status;
 447
 448         ACPI_FUNCTION_NAME(ns_check_sorted_list);
 449
 450         /* The top-level object must be a package */
 451
 452         if (return_object->common.type != ACPI_TYPE_PACKAGE) {
 453                 return (AE_AML_OPERAND_TYPE);
 454         }
 455
 456         /*
 457          * NOTE: assumes list of sub-packages contains no NULL elements.
 458          * Any NULL elements should have been removed by earlier call
 459          * to acpi_ns_remove_null_elements.
 460          */
 461         outer_elements = return_object->package.elements;
 462         outer_element_count = return_object->package.count;
 463         if (!outer_element_count) {
 464                 return (AE_AML_PACKAGE_LIMIT);
 465         }
 466
 467         previous_value = 0;
 468         if (sort_direction == ACPI_SORT_DESCENDING) {
 469                 previous_value = ACPI_UINT32_MAX;
 470         }
 471
 472         /* Examine each subpackage */
 473
 474         for (i = 0; i < outer_element_count; i++) {
 475
 476                 /* Each element of the top-level package must also be a package */
 477
 478                 if ((*outer_elements)->common.type != ACPI_TYPE_PACKAGE) {
 479                         return (AE_AML_OPERAND_TYPE);
 480                 }
 481
 482                 /* Each sub-package must have the minimum length */
 483
 484                 if ((*outer_elements)->package.count < expected_count) {
 485                         return (AE_AML_PACKAGE_LIMIT);
 486                 }
 487
 488                 elements = (*outer_elements)->package.elements;
 489                 obj_desc = elements[sort_index];
 490
 491                 if (obj_desc->common.type != ACPI_TYPE_INTEGER) {
 492                         return (AE_AML_OPERAND_TYPE);
 493                 }
 494
 495                 /*
 496                  * The list must be sorted in the specified order. If we detect a
 497                  * discrepancy, issue a warning and sort the entire list
 498                  */
 499                 if (((sort_direction == ACPI_SORT_ASCENDING) &&
 500                      (obj_desc->integer.value < previous_value)) ||
 501                     ((sort_direction == ACPI_SORT_DESCENDING) &&
 502                      (obj_desc->integer.value > previous_value))) {
 503                         status =
 504                             acpi_ns_sort_list(return_object->package.elements,
 505                                               outer_element_count, sort_index,
 506                                               sort_direction);
 507                         if (ACPI_FAILURE(status)) {
 508                                 return (status);
 509                         }
 510
 511                         data->flags |= ACPI_OBJECT_REPAIRED;
 512
 513                         ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
 514                                           "%s: Repaired unsorted list - now sorted by %s\n",
 515                                           data->pathname, sort_key_name));
 516                         return (AE_OK);
 517                 }
 518
 519                 previous_value = (u32) obj_desc->integer.value;
 520                 outer_elements++;
 521         }
 522
 523         return (AE_OK);
 524 }
 525
 526 /******************************************************************************
 527  *
 528  * FUNCTION:    acpi_ns_remove_null_elements
 529  *
 530  * PARAMETERS:  Data                - Pointer to validation data structure
 531  *              package_type        - An acpi_return_package_types value
 532  *              obj_desc            - A Package object
 533  *
 534  * RETURN:      None.
 535  *
 536  * DESCRIPTION: Remove all NULL package elements from packages that contain
 537  *              a variable number of sub-packages.
 538  *
 539  *****************************************************************************/
 540
 541 void
 542 acpi_ns_remove_null_elements(struct acpi_predefined_data *data,
 543                              u8 package_type,
 544                              union acpi_operand_object *obj_desc)
 545 {
 546         union acpi_operand_object **source;
 547         union acpi_operand_object **dest;
 548         u32 count;
 549         u32 new_count;
 550         u32 i;
 551
 552         ACPI_FUNCTION_NAME(ns_remove_null_elements);
 553
 554         /*
 555          * PTYPE1 packages contain no subpackages.
 556          * PTYPE2 packages contain a variable number of sub-packages. We can
 557          * safely remove all NULL elements from the PTYPE2 packages.
 558          */
 559         switch (package_type) {
 560         case ACPI_PTYPE1_FIXED:
 561         case ACPI_PTYPE1_VAR:
 562         case ACPI_PTYPE1_OPTION:
 563                 return;
 564
 565         case ACPI_PTYPE2:
 566         case ACPI_PTYPE2_COUNT:
 567         case ACPI_PTYPE2_PKG_COUNT:
 568         case ACPI_PTYPE2_FIXED:
 569         case ACPI_PTYPE2_MIN:
 570         case ACPI_PTYPE2_REV_FIXED:
 571                 break;
 572
 573         default:
 574                 return;
 575         }
 576
 577         count = obj_desc->package.count;
 578         new_count = count;
 579
 580         source = obj_desc->package.elements;
 581         dest = source;
 582
 583         /* Examine all elements of the package object, remove nulls */
 584
 585         for (i = 0; i < count; i++) {
 586                 if (!*source) {
 587                         new_count--;
 588                 } else {
 589                         *dest = *source;
 590                         dest++;
 591                 }
 592                 source++;
 593         }
 594
 595         /* Update parent package if any null elements were removed */
 596
 597         if (new_count < count) {
 598                 ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
 599                                   "%s: Found and removed %u NULL elements\n",
 600                                   data->pathname, (count - new_count)));
 601
 602                 /* NULL terminate list and update the package count */
 603
 604                 *dest = NULL;
 605                 obj_desc->package.count = new_count;
 606         }
 607 }
 608
 609 /******************************************************************************
 610  *
 611  * FUNCTION:    acpi_ns_sort_list
 612  *
 613  * PARAMETERS:  Elements            - Package object element list
 614  *              Count               - Element count for above
 615  *              Index               - Sort by which package element
 616  *              sort_direction      - Ascending or Descending sort
 617  *
 618  * RETURN:      Status
 619  *
 620  * DESCRIPTION: Sort the objects that are in a package element list.
 621  *
 622  * NOTE: Assumes that all NULL elements have been removed from the package.
 623  *
 624  *****************************************************************************/
 625
 626 static acpi_status
 627 acpi_ns_sort_list(union acpi_operand_object **elements,
 628                   u32 count, u32 index, u8 sort_direction)
 629 {
 630         union acpi_operand_object *obj_desc1;
 631         union acpi_operand_object *obj_desc2;
 632         union acpi_operand_object *temp_obj;
 633         u32 i;
 634         u32 j;
 635
 636         /* Simple bubble sort */
 637
 638         for (i = 1; i < count; i++) {
 639                 for (j = (count - 1); j >= i; j--) {
 640                         obj_desc1 = elements[j - 1]->package.elements[index];
 641                         obj_desc2 = elements[j]->package.elements[index];
 642
 643                         if (((sort_direction == ACPI_SORT_ASCENDING) &&
 644                              (obj_desc1->integer.value >
 645                               obj_desc2->integer.value))
 646                             || ((sort_direction == ACPI_SORT_DESCENDING)
 647                                 && (obj_desc1->integer.value <
 648                                     obj_desc2->integer.value))) {
 649                                 temp_obj = elements[j - 1];
 650                                 elements[j - 1] = elements[j];
 651                                 elements[j] = temp_obj;
 652                         }
 653                 }
 654         }
 655
 656         return (AE_OK);
 657 }