drivers/acpi/parser/psargs.c

   1 /******************************************************************************
   2  *
   3  * Module Name: psargs - Parse AML opcode arguments
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2005, R. Byron Moore
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions, and the following disclaimer,
  16  *    without modification.
  17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  18  *    substantially similar to the "NO WARRANTY" disclaimer below
  19  *    ("Disclaimer") and any redistribution must be conditioned upon
  20  *    including a substantially similar Disclaimer requirement for further
  21  *    binary redistribution.
  22  * 3. Neither the names of the above-listed copyright holders nor the names
  23  *    of any contributors may be used to endorse or promote products derived
  24  *    from this software without specific prior written permission.
  25  *
  26  * Alternatively, this software may be distributed under the terms of the
  27  * GNU General Public License ("GPL") version 2 as published by the Free
  28  * Software Foundation.
  29  *
  30  * NO WARRANTY
  31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  41  * POSSIBILITY OF SUCH DAMAGES.
  42  */
  43
  44 #include <acpi/acpi.h>
  45 #include <acpi/acparser.h>
  46 #include <acpi/amlcode.h>
  47 #include <acpi/acnamesp.h>
  48
  49 #define _COMPONENT          ACPI_PARSER
  50 ACPI_MODULE_NAME("psargs")
  51
  52 /* Local prototypes */
  53 static u32
  54 acpi_ps_get_next_package_length(struct acpi_parse_state *parser_state);
  55
  56 static union acpi_parse_object *acpi_ps_get_next_field(struct acpi_parse_state
  57                                                        *parser_state);
  58
  59 /*******************************************************************************
  60  *
  61  * FUNCTION:    acpi_ps_get_next_package_length
  62  *
  63  * PARAMETERS:  parser_state        - Current parser state object
  64  *
  65  * RETURN:      Decoded package length. On completion, the AML pointer points
  66  *              past the length byte or bytes.
  67  *
  68  * DESCRIPTION: Decode and return a package length field.
  69  *              Note: Largest package length is 28 bits, from ACPI specification
  70  *
  71  ******************************************************************************/
  72
  73 static u32
  74 acpi_ps_get_next_package_length(struct acpi_parse_state *parser_state)
  75 {
  76         u8 *aml = parser_state->aml;
  77         u32 package_length = 0;
  78         acpi_native_uint byte_count;
  79         u8 byte_zero_mask = 0x3F;       /* Default [0:5] */
  80
  81         ACPI_FUNCTION_TRACE("ps_get_next_package_length");
  82
  83         /*
  84          * Byte 0 bits [6:7] contain the number of additional bytes
  85          * used to encode the package length, either 0,1,2, or 3
  86          */
  87         byte_count = (aml[0] >> 6);
  88         parser_state->aml += (byte_count + 1);
  89
  90         /* Get bytes 3, 2, 1 as needed */
  91
  92         while (byte_count) {
  93                 /*
  94                  * Final bit positions for the package length bytes:
  95                  *      Byte3->[20:27]
  96                  *      Byte2->[12:19]
  97                  *      Byte1->[04:11]
  98                  *      Byte0->[00:03]
  99                  */
 100                 package_length |= (aml[byte_count] << ((byte_count << 3) - 4));
 101
 102                 byte_zero_mask = 0x0F;  /* Use bits [0:3] of byte 0 */
 103                 byte_count--;
 104         }
 105
 106         /* Byte 0 is a special case, either bits [0:3] or [0:5] are used */
 107
 108         package_length |= (aml[0] & byte_zero_mask);
 109         return_UINT32(package_length);
 110 }
 111
 112 /*******************************************************************************
 113  *
 114  * FUNCTION:    acpi_ps_get_next_package_end
 115  *
 116  * PARAMETERS:  parser_state        - Current parser state object
 117  *
 118  * RETURN:      Pointer to end-of-package +1
 119  *
 120  * DESCRIPTION: Get next package length and return a pointer past the end of
 121  *              the package.  Consumes the package length field
 122  *
 123  ******************************************************************************/
 124
 125 u8 *acpi_ps_get_next_package_end(struct acpi_parse_state *parser_state)
 126 {
 127         u8 *start = parser_state->aml;
 128         u32 package_length;
 129
 130         ACPI_FUNCTION_TRACE("ps_get_next_package_end");
 131
 132         /* Function below updates parser_state->Aml */
 133
 134         package_length = acpi_ps_get_next_package_length(parser_state);
 135
 136         return_PTR(start + package_length);     /* end of package */
 137 }
 138
 139 /*******************************************************************************
 140  *
 141  * FUNCTION:    acpi_ps_get_next_namestring
 142  *
 143  * PARAMETERS:  parser_state        - Current parser state object
 144  *
 145  * RETURN:      Pointer to the start of the name string (pointer points into
 146  *              the AML.
 147  *
 148  * DESCRIPTION: Get next raw namestring within the AML stream.  Handles all name
 149  *              prefix characters.  Set parser state to point past the string.
 150  *              (Name is consumed from the AML.)
 151  *
 152  ******************************************************************************/
 153
 154 char *acpi_ps_get_next_namestring(struct acpi_parse_state *parser_state)
 155 {
 156         u8 *start = parser_state->aml;
 157         u8 *end = parser_state->aml;
 158
 159         ACPI_FUNCTION_TRACE("ps_get_next_namestring");
 160
 161         /* Point past any namestring prefix characters (backslash or carat) */
 162
 163         while (acpi_ps_is_prefix_char(*end)) {
 164                 end++;
 165         }
 166
 167         /* Decode the path prefix character */
 168
 169         switch (*end) {
 170         case 0:
 171
 172                 /* null_name */
 173
 174                 if (end == start) {
 175                         start = NULL;
 176                 }
 177                 end++;
 178                 break;
 179
 180         case AML_DUAL_NAME_PREFIX:
 181
 182                 /* Two name segments */
 183
 184                 end += 1 + (2 * ACPI_NAME_SIZE);
 185                 break;
 186
 187         case AML_MULTI_NAME_PREFIX_OP:
 188
 189                 /* Multiple name segments, 4 chars each, count in next byte */
 190
 191                 end += 2 + (*(end + 1) * ACPI_NAME_SIZE);
 192                 break;
 193
 194         default:
 195
 196                 /* Single name segment */
 197
 198                 end += ACPI_NAME_SIZE;
 199                 break;
 200         }
 201
 202         parser_state->aml = end;
 203         return_PTR((char *)start);
 204 }
 205
 206 /*******************************************************************************
 207  *
 208  * FUNCTION:    acpi_ps_get_next_namepath
 209  *
 210  * PARAMETERS:  parser_state        - Current parser state object
 211  *              Arg                 - Where the namepath will be stored
 212  *              arg_count           - If the namepath points to a control method
 213  *                                    the method's argument is returned here.
 214  *              method_call         - Whether the namepath can possibly be the
 215  *                                    start of a method call
 216  *
 217  * RETURN:      Status
 218  *
 219  * DESCRIPTION: Get next name (if method call, return # of required args).
 220  *              Names are looked up in the internal namespace to determine
 221  *              if the name represents a control method.  If a method
 222  *              is found, the number of arguments to the method is returned.
 223  *              This information is critical for parsing to continue correctly.
 224  *
 225  ******************************************************************************/
 226
 227 acpi_status
 228 acpi_ps_get_next_namepath(struct acpi_walk_state *walk_state,
 229                           struct acpi_parse_state *parser_state,
 230                           union acpi_parse_object *arg, u8 method_call)
 231 {
 232         char *path;
 233         union acpi_parse_object *name_op;
 234         acpi_status status = AE_OK;
 235         union acpi_operand_object *method_desc;
 236         struct acpi_namespace_node *node;
 237         union acpi_generic_state scope_info;
 238
 239         ACPI_FUNCTION_TRACE("ps_get_next_namepath");
 240
 241         path = acpi_ps_get_next_namestring(parser_state);
 242
 243         /* Null path case is allowed */
 244
 245         if (path) {
 246                 /*
 247                  * Lookup the name in the internal namespace
 248                  */
 249                 scope_info.scope.node = NULL;
 250                 node = parser_state->start_node;
 251                 if (node) {
 252                         scope_info.scope.node = node;
 253                 }
 254
 255                 /*
 256                  * Lookup object.  We don't want to add anything new to the namespace
 257                  * here, however.  So we use MODE_EXECUTE.  Allow searching of the
 258                  * parent tree, but don't open a new scope -- we just want to lookup the
 259                  * object  (MUST BE mode EXECUTE to perform upsearch)
 260                  */
 261                 status = acpi_ns_lookup(&scope_info, path, ACPI_TYPE_ANY,
 262                                         ACPI_IMODE_EXECUTE,
 263                                         ACPI_NS_SEARCH_PARENT |
 264                                         ACPI_NS_DONT_OPEN_SCOPE, NULL, &node);
 265                 if (ACPI_SUCCESS(status) && method_call) {
 266                         if (node->type == ACPI_TYPE_METHOD) {
 267                                 /* This name is actually a control method invocation */
 268
 269                                 method_desc = acpi_ns_get_attached_object(node);
 270                                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
 271                                                   "Control Method - %p Desc %p Path=%p\n",
 272                                                   node, method_desc, path));
 273
 274                                 name_op = acpi_ps_alloc_op(AML_INT_NAMEPATH_OP);
 275                                 if (!name_op) {
 276                                         return_ACPI_STATUS(AE_NO_MEMORY);
 277                                 }
 278
 279                                 /* Change arg into a METHOD CALL and attach name to it */
 280
 281                                 acpi_ps_init_op(arg, AML_INT_METHODCALL_OP);
 282                                 name_op->common.value.name = path;
 283
 284                                 /* Point METHODCALL/NAME to the METHOD Node */
 285
 286                                 name_op->common.node = node;
 287                                 acpi_ps_append_arg(arg, name_op);
 288
 289                                 if (!method_desc) {
 290                                         ACPI_REPORT_ERROR(("ps_get_next_namepath: Control Method %p has no attached object\n", node));
 291                                         return_ACPI_STATUS(AE_AML_INTERNAL);
 292                                 }
 293
 294                                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
 295                                                   "Control Method - %p Args %X\n",
 296                                                   node,
 297                                                   method_desc->method.
 298                                                   param_count));
 299
 300                                 /* Get the number of arguments to expect */
 301
 302                                 walk_state->arg_count =
 303                                     method_desc->method.param_count;
 304                                 return_ACPI_STATUS(AE_OK);
 305                         }
 306
 307                         /*
 308                          * Else this is normal named object reference.
 309                          * Just init the NAMEPATH object with the pathname.
 310                          * (See code below)
 311                          */
 312                 }
 313
 314                 if (ACPI_FAILURE(status)) {
 315                         /*
 316                          * 1) Any error other than NOT_FOUND is always severe
 317                          * 2) NOT_FOUND is only important if we are executing a method.
 318                          * 3) If executing a cond_ref_of opcode, NOT_FOUND is ok.
 319                          */
 320                         if ((((walk_state->
 321                                parse_flags & ACPI_PARSE_MODE_MASK) ==
 322                               ACPI_PARSE_EXECUTE) && (status == AE_NOT_FOUND)
 323                              && (walk_state->op->common.aml_opcode !=
 324                                  AML_COND_REF_OF_OP))
 325                             || (status != AE_NOT_FOUND)) {
 326                                 ACPI_REPORT_NSERROR(path, status);
 327
 328                                 acpi_os_printf
 329                                     ("search_node %p start_node %p return_node %p\n",
 330                                      scope_info.scope.node,
 331                                      parser_state->start_node, node);
 332                         } else {
 333                                 /*
 334                                  * We got a NOT_FOUND during table load or we encountered
 335                                  * a cond_ref_of(x) where the target does not exist.
 336                                  * Either case is ok
 337                                  */
 338                                 status = AE_OK;
 339                         }
 340                 }
 341         }
 342
 343         /*
 344          * Regardless of success/failure above,
 345          * Just initialize the Op with the pathname.
 346          */
 347         acpi_ps_init_op(arg, AML_INT_NAMEPATH_OP);
 348         arg->common.value.name = path;
 349
 350         return_ACPI_STATUS(status);
 351 }
 352
 353 /*******************************************************************************
 354  *
 355  * FUNCTION:    acpi_ps_get_next_simple_arg
 356  *
 357  * PARAMETERS:  parser_state        - Current parser state object
 358  *              arg_type            - The argument type (AML_*_ARG)
 359  *              Arg                 - Where the argument is returned
 360  *
 361  * RETURN:      None
 362  *
 363  * DESCRIPTION: Get the next simple argument (constant, string, or namestring)
 364  *
 365  ******************************************************************************/
 366
 367 void
 368 acpi_ps_get_next_simple_arg(struct acpi_parse_state *parser_state,
 369                             u32 arg_type, union acpi_parse_object *arg)
 370 {
 371         u32 length;
 372         u16 opcode;
 373         u8 *aml = parser_state->aml;
 374
 375         ACPI_FUNCTION_TRACE_U32("ps_get_next_simple_arg", arg_type);
 376
 377         switch (arg_type) {
 378         case ARGP_BYTEDATA:
 379
 380                 /* Get 1 byte from the AML stream */
 381
 382                 opcode = AML_BYTE_OP;
 383                 arg->common.value.integer = (acpi_integer) * aml;
 384                 length = 1;
 385                 break;
 386
 387         case ARGP_WORDDATA:
 388
 389                 /* Get 2 bytes from the AML stream */
 390
 391                 opcode = AML_WORD_OP;
 392                 ACPI_MOVE_16_TO_64(&arg->common.value.integer, aml);
 393                 length = 2;
 394                 break;
 395
 396         case ARGP_DWORDDATA:
 397
 398                 /* Get 4 bytes from the AML stream */
 399
 400                 opcode = AML_DWORD_OP;
 401                 ACPI_MOVE_32_TO_64(&arg->common.value.integer, aml);
 402                 length = 4;
 403                 break;
 404
 405         case ARGP_QWORDDATA:
 406
 407                 /* Get 8 bytes from the AML stream */
 408
 409                 opcode = AML_QWORD_OP;
 410                 ACPI_MOVE_64_TO_64(&arg->common.value.integer, aml);
 411                 length = 8;
 412                 break;
 413
 414         case ARGP_CHARLIST:
 415
 416                 /* Get a pointer to the string, point past the string */
 417
 418                 opcode = AML_STRING_OP;
 419                 arg->common.value.string = ACPI_CAST_PTR(char, aml);
 420
 421                 /* Find the null terminator */
 422
 423                 length = 0;
 424                 while (aml[length]) {
 425                         length++;
 426                 }
 427                 length++;
 428                 break;
 429
 430         case ARGP_NAME:
 431         case ARGP_NAMESTRING:
 432
 433                 acpi_ps_init_op(arg, AML_INT_NAMEPATH_OP);
 434                 arg->common.value.name =
 435                     acpi_ps_get_next_namestring(parser_state);
 436                 return_VOID;
 437
 438         default:
 439
 440                 ACPI_REPORT_ERROR(("Invalid arg_type %X\n", arg_type));
 441                 return_VOID;
 442         }
 443
 444         acpi_ps_init_op(arg, opcode);
 445         parser_state->aml += length;
 446         return_VOID;
 447 }
 448
 449 /*******************************************************************************
 450  *
 451  * FUNCTION:    acpi_ps_get_next_field
 452  *
 453  * PARAMETERS:  parser_state        - Current parser state object
 454  *
 455  * RETURN:      A newly allocated FIELD op
 456  *
 457  * DESCRIPTION: Get next field (named_field, reserved_field, or access_field)
 458  *
 459  ******************************************************************************/
 460
 461 static union acpi_parse_object *acpi_ps_get_next_field(struct acpi_parse_state
 462                                                        *parser_state)
 463 {
 464         u32 aml_offset = (u32)
 465             ACPI_PTR_DIFF(parser_state->aml,
 466                           parser_state->aml_start);
 467         union acpi_parse_object *field;
 468         u16 opcode;
 469         u32 name;
 470
 471         ACPI_FUNCTION_TRACE("ps_get_next_field");
 472
 473         /* Determine field type */
 474
 475         switch (ACPI_GET8(parser_state->aml)) {
 476         default:
 477
 478                 opcode = AML_INT_NAMEDFIELD_OP;
 479                 break;
 480
 481         case 0x00:
 482
 483                 opcode = AML_INT_RESERVEDFIELD_OP;
 484                 parser_state->aml++;
 485                 break;
 486
 487         case 0x01:
 488
 489                 opcode = AML_INT_ACCESSFIELD_OP;
 490                 parser_state->aml++;
 491                 break;
 492         }
 493
 494         /* Allocate a new field op */
 495
 496         field = acpi_ps_alloc_op(opcode);
 497         if (!field) {
 498                 return_PTR(NULL);
 499         }
 500
 501         field->common.aml_offset = aml_offset;
 502
 503         /* Decode the field type */
 504
 505         switch (opcode) {
 506         case AML_INT_NAMEDFIELD_OP:
 507
 508                 /* Get the 4-character name */
 509
 510                 ACPI_MOVE_32_TO_32(&name, parser_state->aml);
 511                 acpi_ps_set_name(field, name);
 512                 parser_state->aml += ACPI_NAME_SIZE;
 513
 514                 /* Get the length which is encoded as a package length */
 515
 516                 field->common.value.size =
 517                     acpi_ps_get_next_package_length(parser_state);
 518                 break;
 519
 520         case AML_INT_RESERVEDFIELD_OP:
 521
 522                 /* Get the length which is encoded as a package length */
 523
 524                 field->common.value.size =
 525                     acpi_ps_get_next_package_length(parser_state);
 526                 break;
 527
 528         case AML_INT_ACCESSFIELD_OP:
 529
 530                 /*
 531                  * Get access_type and access_attrib and merge into the field Op
 532                  * access_type is first operand, access_attribute is second
 533                  */
 534                 field->common.value.integer =
 535                     (((u32) ACPI_GET8(parser_state->aml) << 8));
 536                 parser_state->aml++;
 537                 field->common.value.integer |= ACPI_GET8(parser_state->aml);
 538                 parser_state->aml++;
 539                 break;
 540
 541         default:
 542
 543                 /* Opcode was set in previous switch */
 544                 break;
 545         }
 546
 547         return_PTR(field);
 548 }
 549
 550 /*******************************************************************************
 551  *
 552  * FUNCTION:    acpi_ps_get_next_arg
 553  *
 554  * PARAMETERS:  walk_state          - Current state
 555  *              parser_state        - Current parser state object
 556  *              arg_type            - The argument type (AML_*_ARG)
 557  *              return_arg          - Where the next arg is returned
 558  *
 559  * RETURN:      Status, and an op object containing the next argument.
 560  *
 561  * DESCRIPTION: Get next argument (including complex list arguments that require
 562  *              pushing the parser stack)
 563  *
 564  ******************************************************************************/
 565
 566 acpi_status
 567 acpi_ps_get_next_arg(struct acpi_walk_state *walk_state,
 568                      struct acpi_parse_state *parser_state,
 569                      u32 arg_type, union acpi_parse_object **return_arg)
 570 {
 571         union acpi_parse_object *arg = NULL;
 572         union acpi_parse_object *prev = NULL;
 573         union acpi_parse_object *field;
 574         u32 subop;
 575         acpi_status status = AE_OK;
 576
 577         ACPI_FUNCTION_TRACE_PTR("ps_get_next_arg", parser_state);
 578
 579         switch (arg_type) {
 580         case ARGP_BYTEDATA:
 581         case ARGP_WORDDATA:
 582         case ARGP_DWORDDATA:
 583         case ARGP_CHARLIST:
 584         case ARGP_NAME:
 585         case ARGP_NAMESTRING:
 586
 587                 /* Constants, strings, and namestrings are all the same size */
 588
 589                 arg = acpi_ps_alloc_op(AML_BYTE_OP);
 590                 if (!arg) {
 591                         return_ACPI_STATUS(AE_NO_MEMORY);
 592                 }
 593                 acpi_ps_get_next_simple_arg(parser_state, arg_type, arg);
 594                 break;
 595
 596         case ARGP_PKGLENGTH:
 597
 598                 /* Package length, nothing returned */
 599
 600                 parser_state->pkg_end =
 601                     acpi_ps_get_next_package_end(parser_state);
 602                 break;
 603
 604         case ARGP_FIELDLIST:
 605
 606                 if (parser_state->aml < parser_state->pkg_end) {
 607                         /* Non-empty list */
 608
 609                         while (parser_state->aml < parser_state->pkg_end) {
 610                                 field = acpi_ps_get_next_field(parser_state);
 611                                 if (!field) {
 612                                         return_ACPI_STATUS(AE_NO_MEMORY);
 613                                 }
 614
 615                                 if (prev) {
 616                                         prev->common.next = field;
 617                                 } else {
 618                                         arg = field;
 619                                 }
 620                                 prev = field;
 621                         }
 622
 623                         /* Skip to End of byte data */
 624
 625                         parser_state->aml = parser_state->pkg_end;
 626                 }
 627                 break;
 628
 629         case ARGP_BYTELIST:
 630
 631                 if (parser_state->aml < parser_state->pkg_end) {
 632                         /* Non-empty list */
 633
 634                         arg = acpi_ps_alloc_op(AML_INT_BYTELIST_OP);
 635                         if (!arg) {
 636                                 return_ACPI_STATUS(AE_NO_MEMORY);
 637                         }
 638
 639                         /* Fill in bytelist data */
 640
 641                         arg->common.value.size = (u32)
 642                             ACPI_PTR_DIFF(parser_state->pkg_end,
 643                                           parser_state->aml);
 644                         arg->named.data = parser_state->aml;
 645
 646                         /* Skip to End of byte data */
 647
 648                         parser_state->aml = parser_state->pkg_end;
 649                 }
 650                 break;
 651
 652         case ARGP_TARGET:
 653         case ARGP_SUPERNAME:
 654         case ARGP_SIMPLENAME:
 655
 656                 subop = acpi_ps_peek_opcode(parser_state);
 657                 if (subop == 0 ||
 658                     acpi_ps_is_leading_char(subop) ||
 659                     acpi_ps_is_prefix_char(subop)) {
 660                         /* null_name or name_string */
 661
 662                         arg = acpi_ps_alloc_op(AML_INT_NAMEPATH_OP);
 663                         if (!arg) {
 664                                 return_ACPI_STATUS(AE_NO_MEMORY);
 665                         }
 666
 667                         status =
 668                             acpi_ps_get_next_namepath(walk_state, parser_state,
 669                                                       arg, 0);
 670                 } else {
 671                         /* Single complex argument, nothing returned */
 672
 673                         walk_state->arg_count = 1;
 674                 }
 675                 break;
 676
 677         case ARGP_DATAOBJ:
 678         case ARGP_TERMARG:
 679
 680                 /* Single complex argument, nothing returned */
 681
 682                 walk_state->arg_count = 1;
 683                 break;
 684
 685         case ARGP_DATAOBJLIST:
 686         case ARGP_TERMLIST:
 687         case ARGP_OBJLIST:
 688
 689                 if (parser_state->aml < parser_state->pkg_end) {
 690                         /* Non-empty list of variable arguments, nothing returned */
 691
 692                         walk_state->arg_count = ACPI_VAR_ARGS;
 693                 }
 694                 break;
 695
 696         default:
 697
 698                 ACPI_REPORT_ERROR(("Invalid arg_type: %X\n", arg_type));
 699                 status = AE_AML_OPERAND_TYPE;
 700                 break;
 701         }
 702
 703         *return_arg = arg;
 704         return_ACPI_STATUS(status);
 705 }