drivers/acpi/acpica/nspredef.c

   1 /******************************************************************************
   2  *
   3  * Module Name: nspredef - Validation of ACPI predefined methods and objects
   4  *              $Revision: 1.1 $
   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 #define ACPI_CREATE_PREDEFINED_TABLE
  46
  47 #include <acpi/acpi.h>
  48 #include "accommon.h"
  49 #include "acnamesp.h"
  50 #include "acpredef.h"
  51
  52 #define _COMPONENT          ACPI_NAMESPACE
  53 ACPI_MODULE_NAME("nspredef")
  54
  55 /*******************************************************************************
  56  *
  57  * This module validates predefined ACPI objects that appear in the namespace,
  58  * at the time they are evaluated (via acpi_evaluate_object). The purpose of this
  59  * validation is to detect problems with BIOS-exposed predefined ACPI objects
  60  * before the results are returned to the ACPI-related drivers.
  61  *
  62  * There are several areas that are validated:
  63  *
  64  *  1) The number of input arguments as defined by the method/object in the
  65  *      ASL is validated against the ACPI specification.
  66  *  2) The type of the return object (if any) is validated against the ACPI
  67  *      specification.
  68  *  3) For returned package objects, the count of package elements is
  69  *      validated, as well as the type of each package element. Nested
  70  *      packages are supported.
  71  *
  72  * For any problems found, a warning message is issued.
  73  *
  74  ******************************************************************************/
  75 /* Local prototypes */
  76 static acpi_status
  77 acpi_ns_check_package(struct acpi_predefined_data *data,
  78                       union acpi_operand_object **return_object_ptr);
  79
  80 static acpi_status
  81 acpi_ns_check_package_list(struct acpi_predefined_data *data,
  82                            const union acpi_predefined_info *package,
  83                            union acpi_operand_object **elements, u32 count);
  84
  85 static acpi_status
  86 acpi_ns_check_package_elements(struct acpi_predefined_data *data,
  87                                union acpi_operand_object **elements,
  88                                u8 type1,
  89                                u32 count1,
  90                                u8 type2, u32 count2, u32 start_index);
  91
  92 static acpi_status
  93 acpi_ns_check_object_type(struct acpi_predefined_data *data,
  94                           union acpi_operand_object **return_object_ptr,
  95                           u32 expected_btypes, u32 package_index);
  96
  97 static acpi_status
  98 acpi_ns_check_reference(struct acpi_predefined_data *data,
  99                         union acpi_operand_object *return_object);
 100
 101 static void acpi_ns_get_expected_types(char *buffer, u32 expected_btypes);
 102
 103 /*
 104  * Names for the types that can be returned by the predefined objects.
 105  * Used for warning messages. Must be in the same order as the ACPI_RTYPEs
 106  */
 107 static const char *acpi_rtype_names[] = {
 108         "/Integer",
 109         "/String",
 110         "/Buffer",
 111         "/Package",
 112         "/Reference",
 113 };
 114
 115 /*******************************************************************************
 116  *
 117  * FUNCTION:    acpi_ns_check_predefined_names
 118  *
 119  * PARAMETERS:  Node            - Namespace node for the method/object
 120  *              user_param_count - Number of parameters actually passed
 121  *              return_status   - Status from the object evaluation
 122  *              return_object_ptr - Pointer to the object returned from the
 123  *                                evaluation of a method or object
 124  *
 125  * RETURN:      Status
 126  *
 127  * DESCRIPTION: Check an ACPI name for a match in the predefined name list.
 128  *
 129  ******************************************************************************/
 130
 131 acpi_status
 132 acpi_ns_check_predefined_names(struct acpi_namespace_node *node,
 133                                u32 user_param_count,
 134                                acpi_status return_status,
 135                                union acpi_operand_object **return_object_ptr)
 136 {
 137         union acpi_operand_object *return_object = *return_object_ptr;
 138         acpi_status status = AE_OK;
 139         const union acpi_predefined_info *predefined;
 140         char *pathname;
 141         struct acpi_predefined_data *data;
 142
 143         /* Match the name for this method/object against the predefined list */
 144
 145         predefined = acpi_ns_check_for_predefined_name(node);
 146
 147         /* Get the full pathname to the object, for use in warning messages */
 148
 149         pathname = acpi_ns_get_external_pathname(node);
 150         if (!pathname) {
 151                 return AE_OK;   /* Could not get pathname, ignore */
 152         }
 153
 154         /*
 155          * Check that the parameter count for this method matches the ASL
 156          * definition. For predefined names, ensure that both the caller and
 157          * the method itself are in accordance with the ACPI specification.
 158          */
 159         acpi_ns_check_parameter_count(pathname, node, user_param_count,
 160                                       predefined);
 161
 162         /* If not a predefined name, we cannot validate the return object */
 163
 164         if (!predefined) {
 165                 goto cleanup;
 166         }
 167
 168         /*
 169          * If the method failed or did not actually return an object, we cannot
 170          * validate the return object
 171          */
 172         if ((return_status != AE_OK) && (return_status != AE_CTRL_RETURN_VALUE)) {
 173                 goto cleanup;
 174         }
 175
 176         /*
 177          * If there is no return value, check if we require a return value for
 178          * this predefined name. Either one return value is expected, or none,
 179          * for both methods and other objects.
 180          *
 181          * Exit now if there is no return object. Warning if one was expected.
 182          */
 183         if (!return_object) {
 184                 if ((predefined->info.expected_btypes) &&
 185                     (!(predefined->info.expected_btypes & ACPI_RTYPE_NONE))) {
 186                         ACPI_WARN_PREDEFINED((AE_INFO, pathname,
 187                                               ACPI_WARN_ALWAYS,
 188                                               "Missing expected return value"));
 189
 190                         status = AE_AML_NO_RETURN_VALUE;
 191                 }
 192                 goto cleanup;
 193         }
 194
 195         /*
 196          * 1) We have a return value, but if one wasn't expected, just exit, this is
 197          * not a problem. For example, if the "Implicit Return" feature is
 198          * enabled, methods will always return a value.
 199          *
 200          * 2) If the return value can be of any type, then we cannot perform any
 201          * validation, exit.
 202          */
 203         if ((!predefined->info.expected_btypes) ||
 204             (predefined->info.expected_btypes == ACPI_RTYPE_ALL)) {
 205                 goto cleanup;
 206         }
 207
 208         /* Create the parameter data block for object validation */
 209
 210         data = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_predefined_data));
 211         if (!data) {
 212                 goto cleanup;
 213         }
 214         data->predefined = predefined;
 215         data->node_flags = node->flags;
 216         data->pathname = pathname;
 217
 218         /*
 219          * Check that the type of the return object is what is expected for
 220          * this predefined name
 221          */
 222         status = acpi_ns_check_object_type(data, return_object_ptr,
 223                                            predefined->info.expected_btypes,
 224                                            ACPI_NOT_PACKAGE_ELEMENT);
 225         if (ACPI_FAILURE(status)) {
 226                 goto check_validation_status;
 227         }
 228
 229         /* For returned Package objects, check the type of all sub-objects */
 230
 231         if (return_object->common.type == ACPI_TYPE_PACKAGE) {
 232                 status = acpi_ns_check_package(data, return_object_ptr);
 233         }
 234
 235         /*
 236          * Perform additional, more complicated repairs on a per-name
 237          * basis.
 238          */
 239         status = acpi_ns_complex_repairs(data, node, status, return_object_ptr);
 240
 241 check_validation_status:
 242         /*
 243          * If the object validation failed or if we successfully repaired one
 244          * or more objects, mark the parent node to suppress further warning
 245          * messages during the next evaluation of the same method/object.
 246          */
 247         if (ACPI_FAILURE(status) || (data->flags & ACPI_OBJECT_REPAIRED)) {
 248                 node->flags |= ANOBJ_EVALUATED;
 249         }
 250         ACPI_FREE(data);
 251
 252 cleanup:
 253         ACPI_FREE(pathname);
 254         return (status);
 255 }
 256
 257 /*******************************************************************************
 258  *
 259  * FUNCTION:    acpi_ns_check_parameter_count
 260  *
 261  * PARAMETERS:  Pathname        - Full pathname to the node (for error msgs)
 262  *              Node            - Namespace node for the method/object
 263  *              user_param_count - Number of args passed in by the caller
 264  *              Predefined      - Pointer to entry in predefined name table
 265  *
 266  * RETURN:      None
 267  *
 268  * DESCRIPTION: Check that the declared (in ASL/AML) parameter count for a
 269  *              predefined name is what is expected (i.e., what is defined in
 270  *              the ACPI specification for this predefined name.)
 271  *
 272  ******************************************************************************/
 273
 274 void
 275 acpi_ns_check_parameter_count(char *pathname,
 276                               struct acpi_namespace_node *node,
 277                               u32 user_param_count,
 278                               const union acpi_predefined_info *predefined)
 279 {
 280         u32 param_count;
 281         u32 required_params_current;
 282         u32 required_params_old;
 283
 284         /* Methods have 0-7 parameters. All other types have zero. */
 285
 286         param_count = 0;
 287         if (node->type == ACPI_TYPE_METHOD) {
 288                 param_count = node->object->method.param_count;
 289         }
 290
 291         if (!predefined) {
 292                 /*
 293                  * Check the parameter count for non-predefined methods/objects.
 294                  *
 295                  * Warning if too few or too many arguments have been passed by the
 296                  * caller. An incorrect number of arguments may not cause the method
 297                  * to fail. However, the method will fail if there are too few
 298                  * arguments and the method attempts to use one of the missing ones.
 299                  */
 300                 if (user_param_count < param_count) {
 301                         ACPI_WARN_PREDEFINED((AE_INFO, pathname,
 302                                               ACPI_WARN_ALWAYS,
 303                                               "Insufficient arguments - needs %u, found %u",
 304                                               param_count, user_param_count));
 305                 } else if (user_param_count > param_count) {
 306                         ACPI_WARN_PREDEFINED((AE_INFO, pathname,
 307                                               ACPI_WARN_ALWAYS,
 308                                               "Excess arguments - needs %u, found %u",
 309                                               param_count, user_param_count));
 310                 }
 311                 return;
 312         }
 313
 314         /*
 315          * Validate the user-supplied parameter count.
 316          * Allow two different legal argument counts (_SCP, etc.)
 317          */
 318         required_params_current = predefined->info.param_count & 0x0F;
 319         required_params_old = predefined->info.param_count >> 4;
 320
 321         if (user_param_count != ACPI_UINT32_MAX) {
 322                 if ((user_param_count != required_params_current) &&
 323                     (user_param_count != required_params_old)) {
 324                         ACPI_WARN_PREDEFINED((AE_INFO, pathname,
 325                                               ACPI_WARN_ALWAYS,
 326                                               "Parameter count mismatch - "
 327                                               "caller passed %u, ACPI requires %u",
 328                                               user_param_count,
 329                                               required_params_current));
 330                 }
 331         }
 332
 333         /*
 334          * Check that the ASL-defined parameter count is what is expected for
 335          * this predefined name (parameter count as defined by the ACPI
 336          * specification)
 337          */
 338         if ((param_count != required_params_current) &&
 339             (param_count != required_params_old)) {
 340                 ACPI_WARN_PREDEFINED((AE_INFO, pathname, node->flags,
 341                                       "Parameter count mismatch - ASL declared %u, ACPI requires %u",
 342                                       param_count, required_params_current));
 343         }
 344 }
 345
 346 /*******************************************************************************
 347  *
 348  * FUNCTION:    acpi_ns_check_for_predefined_name
 349  *
 350  * PARAMETERS:  Node            - Namespace node for the method/object
 351  *
 352  * RETURN:      Pointer to entry in predefined table. NULL indicates not found.
 353  *
 354  * DESCRIPTION: Check an object name against the predefined object list.
 355  *
 356  ******************************************************************************/
 357
 358 const union acpi_predefined_info *acpi_ns_check_for_predefined_name(struct
 359                                                                     acpi_namespace_node
 360                                                                     *node)
 361 {
 362         const union acpi_predefined_info *this_name;
 363
 364         /* Quick check for a predefined name, first character must be underscore */
 365
 366         if (node->name.ascii[0] != '_') {
 367                 return (NULL);
 368         }
 369
 370         /* Search info table for a predefined method/object name */
 371
 372         this_name = predefined_names;
 373         while (this_name->info.name[0]) {
 374                 if (ACPI_COMPARE_NAME(node->name.ascii, this_name->info.name)) {
 375                         return (this_name);
 376                 }
 377
 378                 /*
 379                  * Skip next entry in the table if this name returns a Package
 380                  * (next entry contains the package info)
 381                  */
 382                 if (this_name->info.expected_btypes & ACPI_RTYPE_PACKAGE) {
 383                         this_name++;
 384                 }
 385
 386                 this_name++;
 387         }
 388
 389         return (NULL);          /* Not found */
 390 }
 391
 392 /*******************************************************************************
 393  *
 394  * FUNCTION:    acpi_ns_check_package
 395  *
 396  * PARAMETERS:  Data            - Pointer to validation data structure
 397  *              return_object_ptr - Pointer to the object returned from the
 398  *                                evaluation of a method or object
 399  *
 400  * RETURN:      Status
 401  *
 402  * DESCRIPTION: Check a returned package object for the correct count and
 403  *              correct type of all sub-objects.
 404  *
 405  ******************************************************************************/
 406
 407 static acpi_status
 408 acpi_ns_check_package(struct acpi_predefined_data *data,
 409                       union acpi_operand_object **return_object_ptr)
 410 {
 411         union acpi_operand_object *return_object = *return_object_ptr;
 412         const union acpi_predefined_info *package;
 413         union acpi_operand_object **elements;
 414         acpi_status status = AE_OK;
 415         u32 expected_count;
 416         u32 count;
 417         u32 i;
 418
 419         ACPI_FUNCTION_NAME(ns_check_package);
 420
 421         /* The package info for this name is in the next table entry */
 422
 423         package = data->predefined + 1;
 424
 425         ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
 426                           "%s Validating return Package of Type %X, Count %X\n",
 427                           data->pathname, package->ret_info.type,
 428                           return_object->package.count));
 429
 430         /* Extract package count and elements array */
 431
 432         elements = return_object->package.elements;
 433         count = return_object->package.count;
 434
 435         /* The package must have at least one element, else invalid */
 436
 437         if (!count) {
 438                 ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
 439                                       "Return Package has no elements (empty)"));
 440
 441                 return (AE_AML_OPERAND_VALUE);
 442         }
 443
 444         /*
 445          * Decode the type of the expected package contents
 446          *
 447          * PTYPE1 packages contain no subpackages
 448          * PTYPE2 packages contain sub-packages
 449          */
 450         switch (package->ret_info.type) {
 451         case ACPI_PTYPE1_FIXED:
 452
 453                 /*
 454                  * The package count is fixed and there are no sub-packages
 455                  *
 456                  * If package is too small, exit.
 457                  * If package is larger than expected, issue warning but continue
 458                  */
 459                 expected_count =
 460                     package->ret_info.count1 + package->ret_info.count2;
 461                 if (count < expected_count) {
 462                         goto package_too_small;
 463                 } else if (count > expected_count) {
 464                         ACPI_WARN_PREDEFINED((AE_INFO, data->pathname,
 465                                               data->node_flags,
 466                                               "Return Package is larger than needed - "
 467                                               "found %u, expected %u", count,
 468                                               expected_count));
 469                 }
 470
 471                 /* Validate all elements of the returned package */
 472
 473                 status = acpi_ns_check_package_elements(data, elements,
 474                                                         package->ret_info.
 475                                                         object_type1,
 476                                                         package->ret_info.
 477                                                         count1,
 478                                                         package->ret_info.
 479                                                         object_type2,
 480                                                         package->ret_info.
 481                                                         count2, 0);
 482                 break;
 483
 484         case ACPI_PTYPE1_VAR:
 485
 486                 /*
 487                  * The package count is variable, there are no sub-packages, and all
 488                  * elements must be of the same type
 489                  */
 490                 for (i = 0; i < count; i++) {
 491                         status = acpi_ns_check_object_type(data, elements,
 492                                                            package->ret_info.
 493                                                            object_type1, i);
 494                         if (ACPI_FAILURE(status)) {
 495                                 return (status);
 496                         }
 497                         elements++;
 498                 }
 499                 break;
 500
 501         case ACPI_PTYPE1_OPTION:
 502
 503                 /*
 504                  * The package count is variable, there are no sub-packages. There are
 505                  * a fixed number of required elements, and a variable number of
 506                  * optional elements.
 507                  *
 508                  * Check if package is at least as large as the minimum required
 509                  */
 510                 expected_count = package->ret_info3.count;
 511                 if (count < expected_count) {
 512                         goto package_too_small;
 513                 }
 514
 515                 /* Variable number of sub-objects */
 516
 517                 for (i = 0; i < count; i++) {
 518                         if (i < package->ret_info3.count) {
 519
 520                                 /* These are the required package elements (0, 1, or 2) */
 521
 522                                 status =
 523                                     acpi_ns_check_object_type(data, elements,
 524                                                               package->
 525                                                               ret_info3.
 526                                                               object_type[i],
 527                                                               i);
 528                                 if (ACPI_FAILURE(status)) {
 529                                         return (status);
 530                                 }
 531                         } else {
 532                                 /* These are the optional package elements */
 533
 534                                 status =
 535                                     acpi_ns_check_object_type(data, elements,
 536                                                               package->
 537                                                               ret_info3.
 538                                                               tail_object_type,
 539                                                               i);
 540                                 if (ACPI_FAILURE(status)) {
 541                                         return (status);
 542                                 }
 543                         }
 544                         elements++;
 545                 }
 546                 break;
 547
 548         case ACPI_PTYPE2_REV_FIXED:
 549
 550                 /* First element is the (Integer) revision */
 551
 552                 status = acpi_ns_check_object_type(data, elements,
 553                                                    ACPI_RTYPE_INTEGER, 0);
 554                 if (ACPI_FAILURE(status)) {
 555                         return (status);
 556                 }
 557
 558                 elements++;
 559                 count--;
 560
 561                 /* Examine the sub-packages */
 562
 563                 status =
 564                     acpi_ns_check_package_list(data, package, elements, count);
 565                 break;
 566
 567         case ACPI_PTYPE2_PKG_COUNT:
 568
 569                 /* First element is the (Integer) count of sub-packages to follow */
 570
 571                 status = acpi_ns_check_object_type(data, elements,
 572                                                    ACPI_RTYPE_INTEGER, 0);
 573                 if (ACPI_FAILURE(status)) {
 574                         return (status);
 575                 }
 576
 577                 /*
 578                  * Count cannot be larger than the parent package length, but allow it
 579                  * to be smaller. The >= accounts for the Integer above.
 580                  */
 581                 expected_count = (u32) (*elements)->integer.value;
 582                 if (expected_count >= count) {
 583                         goto package_too_small;
 584                 }
 585
 586                 count = expected_count;
 587                 elements++;
 588
 589                 /* Examine the sub-packages */
 590
 591                 status =
 592                     acpi_ns_check_package_list(data, package, elements, count);
 593                 break;
 594
 595         case ACPI_PTYPE2:
 596         case ACPI_PTYPE2_FIXED:
 597         case ACPI_PTYPE2_MIN:
 598         case ACPI_PTYPE2_COUNT:
 599
 600                 /*
 601                  * These types all return a single Package that consists of a
 602                  * variable number of sub-Packages.
 603                  *
 604                  * First, ensure that the first element is a sub-Package. If not,
 605                  * the BIOS may have incorrectly returned the object as a single
 606                  * package instead of a Package of Packages (a common error if
 607                  * there is only one entry). We may be able to repair this by
 608                  * wrapping the returned Package with a new outer Package.
 609                  */
 610                 if (*elements
 611                     && ((*elements)->common.type != ACPI_TYPE_PACKAGE)) {
 612
 613                         /* Create the new outer package and populate it */
 614
 615                         status =
 616                             acpi_ns_repair_package_list(data,
 617                                                         return_object_ptr);
 618                         if (ACPI_FAILURE(status)) {
 619                                 return (status);
 620                         }
 621
 622                         /* Update locals to point to the new package (of 1 element) */
 623
 624                         return_object = *return_object_ptr;
 625                         elements = return_object->package.elements;
 626                         count = 1;
 627                 }
 628
 629                 /* Examine the sub-packages */
 630
 631                 status =
 632                     acpi_ns_check_package_list(data, package, elements, count);
 633                 break;
 634
 635         default:
 636
 637                 /* Should not get here if predefined info table is correct */
 638
 639                 ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
 640                                       "Invalid internal return type in table entry: %X",
 641                                       package->ret_info.type));
 642
 643                 return (AE_AML_INTERNAL);
 644         }
 645
 646         return (status);
 647
 648 package_too_small:
 649
 650         /* Error exit for the case with an incorrect package count */
 651
 652         ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
 653                               "Return Package is too small - found %u elements, expected %u",
 654                               count, expected_count));
 655
 656         return (AE_AML_OPERAND_VALUE);
 657 }
 658
 659 /*******************************************************************************
 660  *
 661  * FUNCTION:    acpi_ns_check_package_list
 662  *
 663  * PARAMETERS:  Data            - Pointer to validation data structure
 664  *              Package         - Pointer to package-specific info for method
 665  *              Elements        - Element list of parent package. All elements
 666  *                                of this list should be of type Package.
 667  *              Count           - Count of subpackages
 668  *
 669  * RETURN:      Status
 670  *
 671  * DESCRIPTION: Examine a list of subpackages
 672  *
 673  ******************************************************************************/
 674
 675 static acpi_status
 676 acpi_ns_check_package_list(struct acpi_predefined_data *data,
 677                            const union acpi_predefined_info *package,
 678                            union acpi_operand_object **elements, u32 count)
 679 {
 680         union acpi_operand_object *sub_package;
 681         union acpi_operand_object **sub_elements;
 682         acpi_status status;
 683         u8 non_trailing_null = FALSE;
 684         u32 expected_count;
 685         u32 i;
 686         u32 j;
 687
 688         /* Validate each sub-Package in the parent Package */
 689
 690         for (i = 0; i < count; i++) {
 691                 /*
 692                  * Handling for NULL package elements. For now, we will simply allow
 693                  * a parent package with trailing NULL elements. This can happen if
 694                  * the package was defined to be longer than the initializer list.
 695                  * This is legal as per the ACPI specification. It is often used
 696                  * to allow for dynamic initialization of a Package.
 697                  *
 698                  * A future enhancement may be to simply truncate the package to
 699                  * remove the trailing NULL elements.
 700                  */
 701                 if (!(*elements)) {
 702                         if (!non_trailing_null) {
 703
 704                                 /* Ensure the remaining elements are all NULL */
 705
 706                                 for (j = 1; j < (count - i + 1); j++) {
 707                                         if (elements[j]) {
 708                                                 non_trailing_null = TRUE;
 709                                         }
 710                                 }
 711
 712                                 if (!non_trailing_null) {
 713
 714                                         /* Ignore the trailing NULL elements */
 715
 716                                         return (AE_OK);
 717                                 }
 718                         }
 719
 720                         /* There are trailing non-null elements, issue warning */
 721
 722                         ACPI_WARN_PREDEFINED((AE_INFO, data->pathname,
 723                                               data->node_flags,
 724                                               "Found NULL element at package index %u",
 725                                               i));
 726                         elements++;
 727                         continue;
 728                 }
 729
 730                 sub_package = *elements;
 731                 sub_elements = sub_package->package.elements;
 732
 733                 /* Each sub-object must be of type Package */
 734
 735                 status = acpi_ns_check_object_type(data, &sub_package,
 736                                                    ACPI_RTYPE_PACKAGE, i);
 737                 if (ACPI_FAILURE(status)) {
 738                         return (status);
 739                 }
 740
 741                 /* Examine the different types of expected sub-packages */
 742
 743                 switch (package->ret_info.type) {
 744                 case ACPI_PTYPE2:
 745                 case ACPI_PTYPE2_PKG_COUNT:
 746                 case ACPI_PTYPE2_REV_FIXED:
 747
 748                         /* Each subpackage has a fixed number of elements */
 749
 750                         expected_count =
 751                             package->ret_info.count1 + package->ret_info.count2;
 752                         if (sub_package->package.count < expected_count) {
 753                                 goto package_too_small;
 754                         }
 755
 756                         status =
 757                             acpi_ns_check_package_elements(data, sub_elements,
 758                                                            package->ret_info.
 759                                                            object_type1,
 760                                                            package->ret_info.
 761                                                            count1,
 762                                                            package->ret_info.
 763                                                            object_type2,
 764                                                            package->ret_info.
 765                                                            count2, 0);
 766                         if (ACPI_FAILURE(status)) {
 767                                 return (status);
 768                         }
 769                         break;
 770
 771                 case ACPI_PTYPE2_FIXED:
 772
 773                         /* Each sub-package has a fixed length */
 774
 775                         expected_count = package->ret_info2.count;
 776                         if (sub_package->package.count < expected_count) {
 777                                 goto package_too_small;
 778                         }
 779
 780                         /* Check the type of each sub-package element */
 781
 782                         for (j = 0; j < expected_count; j++) {
 783                                 status =
 784                                     acpi_ns_check_object_type(data,
 785                                                               &sub_elements[j],
 786                                                               package->
 787                                                               ret_info2.
 788                                                               object_type[j],
 789                                                               j);
 790                                 if (ACPI_FAILURE(status)) {
 791                                         return (status);
 792                                 }
 793                         }
 794                         break;
 795
 796                 case ACPI_PTYPE2_MIN:
 797
 798                         /* Each sub-package has a variable but minimum length */
 799
 800                         expected_count = package->ret_info.count1;
 801                         if (sub_package->package.count < expected_count) {
 802                                 goto package_too_small;
 803                         }
 804
 805                         /* Check the type of each sub-package element */
 806
 807                         status =
 808                             acpi_ns_check_package_elements(data, sub_elements,
 809                                                            package->ret_info.
 810                                                            object_type1,
 811                                                            sub_package->package.
 812                                                            count, 0, 0, 0);
 813                         if (ACPI_FAILURE(status)) {
 814                                 return (status);
 815                         }
 816                         break;
 817
 818                 case ACPI_PTYPE2_COUNT:
 819
 820                         /*
 821                          * First element is the (Integer) count of elements, including
 822                          * the count field.
 823                          */
 824                         status = acpi_ns_check_object_type(data, sub_elements,
 825                                                            ACPI_RTYPE_INTEGER,
 826                                                            0);
 827                         if (ACPI_FAILURE(status)) {
 828                                 return (status);
 829                         }
 830
 831                         /*
 832                          * Make sure package is large enough for the Count and is
 833                          * is as large as the minimum size
 834                          */
 835                         expected_count = (u32)(*sub_elements)->integer.value;
 836                         if (sub_package->package.count < expected_count) {
 837                                 goto package_too_small;
 838                         }
 839                         if (sub_package->package.count <
 840                             package->ret_info.count1) {
 841                                 expected_count = package->ret_info.count1;
 842                                 goto package_too_small;
 843                         }
 844
 845                         /* Check the type of each sub-package element */
 846
 847                         status =
 848                             acpi_ns_check_package_elements(data,
 849                                                            (sub_elements + 1),
 850                                                            package->ret_info.
 851                                                            object_type1,
 852                                                            (expected_count - 1),
 853                                                            0, 0, 1);
 854                         if (ACPI_FAILURE(status)) {
 855                                 return (status);
 856                         }
 857                         break;
 858
 859                 default:        /* Should not get here, type was validated by caller */
 860
 861                         return (AE_AML_INTERNAL);
 862                 }
 863
 864                 elements++;
 865         }
 866
 867         return (AE_OK);
 868
 869 package_too_small:
 870
 871         /* The sub-package count was smaller than required */
 872
 873         ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
 874                               "Return Sub-Package[%u] is too small - found %u elements, expected %u",
 875                               i, sub_package->package.count, expected_count));
 876
 877         return (AE_AML_OPERAND_VALUE);
 878 }
 879
 880 /*******************************************************************************
 881  *
 882  * FUNCTION:    acpi_ns_check_package_elements
 883  *
 884  * PARAMETERS:  Data            - Pointer to validation data structure
 885  *              Elements        - Pointer to the package elements array
 886  *              Type1           - Object type for first group
 887  *              Count1          - Count for first group
 888  *              Type2           - Object type for second group
 889  *              Count2          - Count for second group
 890  *              start_index     - Start of the first group of elements
 891  *
 892  * RETURN:      Status
 893  *
 894  * DESCRIPTION: Check that all elements of a package are of the correct object
 895  *              type. Supports up to two groups of different object types.
 896  *
 897  ******************************************************************************/
 898
 899 static acpi_status
 900 acpi_ns_check_package_elements(struct acpi_predefined_data *data,
 901                                union acpi_operand_object **elements,
 902                                u8 type1,
 903                                u32 count1,
 904                                u8 type2, u32 count2, u32 start_index)
 905 {
 906         union acpi_operand_object **this_element = elements;
 907         acpi_status status;
 908         u32 i;
 909
 910         /*
 911          * Up to two groups of package elements are supported by the data
 912          * structure. All elements in each group must be of the same type.
 913          * The second group can have a count of zero.
 914          */
 915         for (i = 0; i < count1; i++) {
 916                 status = acpi_ns_check_object_type(data, this_element,
 917                                                    type1, i + start_index);
 918                 if (ACPI_FAILURE(status)) {
 919                         return (status);
 920                 }
 921                 this_element++;
 922         }
 923
 924         for (i = 0; i < count2; i++) {
 925                 status = acpi_ns_check_object_type(data, this_element,
 926                                                    type2,
 927                                                    (i + count1 + start_index));
 928                 if (ACPI_FAILURE(status)) {
 929                         return (status);
 930                 }
 931                 this_element++;
 932         }
 933
 934         return (AE_OK);
 935 }
 936
 937 /*******************************************************************************
 938  *
 939  * FUNCTION:    acpi_ns_check_object_type
 940  *
 941  * PARAMETERS:  Data            - Pointer to validation data structure
 942  *              return_object_ptr - Pointer to the object returned from the
 943  *                                evaluation of a method or object
 944  *              expected_btypes - Bitmap of expected return type(s)
 945  *              package_index   - Index of object within parent package (if
 946  *                                applicable - ACPI_NOT_PACKAGE_ELEMENT
 947  *                                otherwise)
 948  *
 949  * RETURN:      Status
 950  *
 951  * DESCRIPTION: Check the type of the return object against the expected object
 952  *              type(s). Use of Btype allows multiple expected object types.
 953  *
 954  ******************************************************************************/
 955
 956 static acpi_status
 957 acpi_ns_check_object_type(struct acpi_predefined_data *data,
 958                           union acpi_operand_object **return_object_ptr,
 959                           u32 expected_btypes, u32 package_index)
 960 {
 961         union acpi_operand_object *return_object = *return_object_ptr;
 962         acpi_status status = AE_OK;
 963         u32 return_btype;
 964         char type_buffer[48];   /* Room for 5 types */
 965
 966         /*
 967          * If we get a NULL return_object here, it is a NULL package element,
 968          * and this is always an error.
 969          */
 970         if (!return_object) {
 971                 goto type_error_exit;
 972         }
 973
 974         /* A Namespace node should not get here, but make sure */
 975
 976         if (ACPI_GET_DESCRIPTOR_TYPE(return_object) == ACPI_DESC_TYPE_NAMED) {
 977                 ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
 978                                       "Invalid return type - Found a Namespace node [%4.4s] type %s",
 979                                       return_object->node.name.ascii,
 980                                       acpi_ut_get_type_name(return_object->node.
 981                                                             type)));
 982                 return (AE_AML_OPERAND_TYPE);
 983         }
 984
 985         /*
 986          * Convert the object type (ACPI_TYPE_xxx) to a bitmapped object type.
 987          * The bitmapped type allows multiple possible return types.
 988          *
 989          * Note, the cases below must handle all of the possible types returned
 990          * from all of the predefined names (including elements of returned
 991          * packages)
 992          */
 993         switch (return_object->common.type) {
 994         case ACPI_TYPE_INTEGER:
 995                 return_btype = ACPI_RTYPE_INTEGER;
 996                 break;
 997
 998         case ACPI_TYPE_BUFFER:
 999                 return_btype = ACPI_RTYPE_BUFFER;
1000                 break;
1001
1002         case ACPI_TYPE_STRING:
1003                 return_btype = ACPI_RTYPE_STRING;
1004                 break;
1005
1006         case ACPI_TYPE_PACKAGE:
1007                 return_btype = ACPI_RTYPE_PACKAGE;
1008                 break;
1009
1010         case ACPI_TYPE_LOCAL_REFERENCE:
1011                 return_btype = ACPI_RTYPE_REFERENCE;
1012                 break;
1013
1014         default:
1015                 /* Not one of the supported objects, must be incorrect */
1016
1017                 goto type_error_exit;
1018         }
1019
1020         /* Is the object one of the expected types? */
1021
1022         if (!(return_btype & expected_btypes)) {
1023
1024                 /* Type mismatch -- attempt repair of the returned object */
1025
1026                 status = acpi_ns_repair_object(data, expected_btypes,
1027                                                package_index,
1028                                                return_object_ptr);
1029                 if (ACPI_SUCCESS(status)) {
1030                         return (AE_OK); /* Repair was successful */
1031                 }
1032                 goto type_error_exit;
1033         }
1034
1035         /* For reference objects, check that the reference type is correct */
1036
1037         if (return_object->common.type == ACPI_TYPE_LOCAL_REFERENCE) {
1038                 status = acpi_ns_check_reference(data, return_object);
1039         }
1040
1041         return (status);
1042
1043       type_error_exit:
1044
1045         /* Create a string with all expected types for this predefined object */
1046
1047         acpi_ns_get_expected_types(type_buffer, expected_btypes);
1048
1049         if (package_index == ACPI_NOT_PACKAGE_ELEMENT) {
1050                 ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
1051                                       "Return type mismatch - found %s, expected %s",
1052                                       acpi_ut_get_object_type_name
1053                                       (return_object), type_buffer));
1054         } else {
1055                 ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
1056                                       "Return Package type mismatch at index %u - "
1057                                       "found %s, expected %s", package_index,
1058                                       acpi_ut_get_object_type_name
1059                                       (return_object), type_buffer));
1060         }
1061
1062         return (AE_AML_OPERAND_TYPE);
1063 }
1064
1065 /*******************************************************************************
1066  *
1067  * FUNCTION:    acpi_ns_check_reference
1068  *
1069  * PARAMETERS:  Data            - Pointer to validation data structure
1070  *              return_object   - Object returned from the evaluation of a
1071  *                                method or object
1072  *
1073  * RETURN:      Status
1074  *
1075  * DESCRIPTION: Check a returned reference object for the correct reference
1076  *              type. The only reference type that can be returned from a
1077  *              predefined method is a named reference. All others are invalid.
1078  *
1079  ******************************************************************************/
1080
1081 static acpi_status
1082 acpi_ns_check_reference(struct acpi_predefined_data *data,
1083                         union acpi_operand_object *return_object)
1084 {
1085
1086         /*
1087          * Check the reference object for the correct reference type (opcode).
1088          * The only type of reference that can be converted to an union acpi_object is
1089          * a reference to a named object (reference class: NAME)
1090          */
1091         if (return_object->reference.class == ACPI_REFCLASS_NAME) {
1092                 return (AE_OK);
1093         }
1094
1095         ACPI_WARN_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
1096                               "Return type mismatch - unexpected reference object type [%s] %2.2X",
1097                               acpi_ut_get_reference_name(return_object),
1098                               return_object->reference.class));
1099
1100         return (AE_AML_OPERAND_TYPE);
1101 }
1102
1103 /*******************************************************************************
1104  *
1105  * FUNCTION:    acpi_ns_get_expected_types
1106  *
1107  * PARAMETERS:  Buffer          - Pointer to where the string is returned
1108  *              expected_btypes - Bitmap of expected return type(s)
1109  *
1110  * RETURN:      Buffer is populated with type names.
1111  *
1112  * DESCRIPTION: Translate the expected types bitmap into a string of ascii
1113  *              names of expected types, for use in warning messages.
1114  *
1115  ******************************************************************************/
1116
1117 static void acpi_ns_get_expected_types(char *buffer, u32 expected_btypes)
1118 {
1119         u32 this_rtype;
1120         u32 i;
1121         u32 j;
1122
1123         j = 1;
1124         buffer[0] = 0;
1125         this_rtype = ACPI_RTYPE_INTEGER;
1126
1127         for (i = 0; i < ACPI_NUM_RTYPES; i++) {
1128
1129                 /* If one of the expected types, concatenate the name of this type */
1130
1131                 if (expected_btypes & this_rtype) {
1132                         ACPI_STRCAT(buffer, &acpi_rtype_names[i][j]);
1133                         j = 0;  /* Use name separator from now on */
1134                 }
1135                 this_rtype <<= 1;       /* Next Rtype */
1136         }
1137 }