drivers/acpi/acpica/psobject.c

   1 /******************************************************************************
   2  *
   3  * Module Name: psobject - Support for parse objects
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2016, Intel Corp.
   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 "accommon.h"
  46 #include "acparser.h"
  47 #include "amlcode.h"
  48
  49 #define _COMPONENT          ACPI_PARSER
  50 ACPI_MODULE_NAME("psobject")
  51
  52 /* Local prototypes */
  53 static acpi_status acpi_ps_get_aml_opcode(struct acpi_walk_state *walk_state);
  54
  55 /*******************************************************************************
  56  *
  57  * FUNCTION:    acpi_ps_get_aml_opcode
  58  *
  59  * PARAMETERS:  walk_state          - Current state
  60  *
  61  * RETURN:      Status
  62  *
  63  * DESCRIPTION: Extract the next AML opcode from the input stream.
  64  *
  65  ******************************************************************************/
  66
  67 static acpi_status acpi_ps_get_aml_opcode(struct acpi_walk_state *walk_state)
  68 {
  69         u32 aml_offset;
  70
  71         ACPI_FUNCTION_TRACE_PTR(ps_get_aml_opcode, walk_state);
  72
  73         walk_state->aml = walk_state->parser_state.aml;
  74         walk_state->opcode = acpi_ps_peek_opcode(&(walk_state->parser_state));
  75
  76         /*
  77          * First cut to determine what we have found:
  78          * 1) A valid AML opcode
  79          * 2) A name string
  80          * 3) An unknown/invalid opcode
  81          */
  82         walk_state->op_info = acpi_ps_get_opcode_info(walk_state->opcode);
  83
  84         switch (walk_state->op_info->class) {
  85         case AML_CLASS_ASCII:
  86         case AML_CLASS_PREFIX:
  87                 /*
  88                  * Starts with a valid prefix or ASCII char, this is a name
  89                  * string. Convert the bare name string to a namepath.
  90                  */
  91                 walk_state->opcode = AML_INT_NAMEPATH_OP;
  92                 walk_state->arg_types = ARGP_NAMESTRING;
  93                 break;
  94
  95         case AML_CLASS_UNKNOWN:
  96
  97                 /* The opcode is unrecognized. Complain and skip unknown opcodes */
  98
  99                 if (walk_state->pass_number == 2) {
 100                         aml_offset = (u32)ACPI_PTR_DIFF(walk_state->aml,
 101                                                         walk_state->
 102                                                         parser_state.aml_start);
 103
 104                         ACPI_ERROR((AE_INFO,
 105                                     "Unknown opcode 0x%.2X at table offset 0x%.4X, ignoring",
 106                                     walk_state->opcode,
 107                                     (u32)(aml_offset +
 108                                           sizeof(struct acpi_table_header))));
 109
 110                         ACPI_DUMP_BUFFER((walk_state->parser_state.aml - 16),
 111                                          48);
 112
 113 #ifdef ACPI_ASL_COMPILER
 114                         /*
 115                          * This is executed for the disassembler only. Output goes
 116                          * to the disassembled ASL output file.
 117                          */
 118                         acpi_os_printf
 119                             ("/*\nError: Unknown opcode 0x%.2X at table offset 0x%.4X, context:\n",
 120                              walk_state->opcode,
 121                              (u32)(aml_offset +
 122                                    sizeof(struct acpi_table_header)));
 123
 124                         ACPI_ERROR((AE_INFO,
 125                                     "Aborting disassembly, AML byte code is corrupt"));
 126
 127                         /* Dump the context surrounding the invalid opcode */
 128
 129                         acpi_ut_dump_buffer(((u8 *)walk_state->parser_state.
 130                                              aml - 16), 48, DB_BYTE_DISPLAY,
 131                                             (aml_offset +
 132                                              sizeof(struct acpi_table_header) -
 133                                              16));
 134                         acpi_os_printf(" */\n");
 135
 136                         /*
 137                          * Just abort the disassembly, cannot continue because the
 138                          * parser is essentially lost. The disassembler can then
 139                          * randomly fail because an ill-constructed parse tree
 140                          * can result.
 141                          */
 142                         return_ACPI_STATUS(AE_AML_BAD_OPCODE);
 143 #endif
 144                 }
 145
 146                 /* Increment past one-byte or two-byte opcode */
 147
 148                 walk_state->parser_state.aml++;
 149                 if (walk_state->opcode > 0xFF) {        /* Can only happen if first byte is 0x5B */
 150                         walk_state->parser_state.aml++;
 151                 }
 152
 153                 return_ACPI_STATUS(AE_CTRL_PARSE_CONTINUE);
 154
 155         default:
 156
 157                 /* Found opcode info, this is a normal opcode */
 158
 159                 walk_state->parser_state.aml +=
 160                     acpi_ps_get_opcode_size(walk_state->opcode);
 161                 walk_state->arg_types = walk_state->op_info->parse_args;
 162                 break;
 163         }
 164
 165         return_ACPI_STATUS(AE_OK);
 166 }
 167
 168 /*******************************************************************************
 169  *
 170  * FUNCTION:    acpi_ps_build_named_op
 171  *
 172  * PARAMETERS:  walk_state          - Current state
 173  *              aml_op_start        - Begin of named Op in AML
 174  *              unnamed_op          - Early Op (not a named Op)
 175  *              op                  - Returned Op
 176  *
 177  * RETURN:      Status
 178  *
 179  * DESCRIPTION: Parse a named Op
 180  *
 181  ******************************************************************************/
 182
 183 acpi_status
 184 acpi_ps_build_named_op(struct acpi_walk_state *walk_state,
 185                        u8 *aml_op_start,
 186                        union acpi_parse_object *unnamed_op,
 187                        union acpi_parse_object **op)
 188 {
 189         acpi_status status = AE_OK;
 190         union acpi_parse_object *arg = NULL;
 191
 192         ACPI_FUNCTION_TRACE_PTR(ps_build_named_op, walk_state);
 193
 194         unnamed_op->common.value.arg = NULL;
 195         unnamed_op->common.arg_list_length = 0;
 196         unnamed_op->common.aml_opcode = walk_state->opcode;
 197
 198         /*
 199          * Get and append arguments until we find the node that contains
 200          * the name (the type ARGP_NAME).
 201          */
 202         while (GET_CURRENT_ARG_TYPE(walk_state->arg_types) &&
 203                (GET_CURRENT_ARG_TYPE(walk_state->arg_types) != ARGP_NAME)) {
 204                 status =
 205                     acpi_ps_get_next_arg(walk_state,
 206                                          &(walk_state->parser_state),
 207                                          GET_CURRENT_ARG_TYPE(walk_state->
 208                                                               arg_types), &arg);
 209                 if (ACPI_FAILURE(status)) {
 210                         return_ACPI_STATUS(status);
 211                 }
 212
 213                 acpi_ps_append_arg(unnamed_op, arg);
 214                 INCREMENT_ARG_LIST(walk_state->arg_types);
 215         }
 216
 217         /*
 218          * Make sure that we found a NAME and didn't run out of arguments
 219          */
 220         if (!GET_CURRENT_ARG_TYPE(walk_state->arg_types)) {
 221                 return_ACPI_STATUS(AE_AML_NO_OPERAND);
 222         }
 223
 224         /* We know that this arg is a name, move to next arg */
 225
 226         INCREMENT_ARG_LIST(walk_state->arg_types);
 227
 228         /*
 229          * Find the object. This will either insert the object into
 230          * the namespace or simply look it up
 231          */
 232         walk_state->op = NULL;
 233
 234         status = walk_state->descending_callback(walk_state, op);
 235         if (ACPI_FAILURE(status)) {
 236                 if (status != AE_CTRL_TERMINATE) {
 237                         ACPI_EXCEPTION((AE_INFO, status,
 238                                         "During name lookup/catalog"));
 239                 }
 240                 return_ACPI_STATUS(status);
 241         }
 242
 243         if (!*op) {
 244                 return_ACPI_STATUS(AE_CTRL_PARSE_CONTINUE);
 245         }
 246
 247         status = acpi_ps_next_parse_state(walk_state, *op, status);
 248         if (ACPI_FAILURE(status)) {
 249                 if (status == AE_CTRL_PENDING) {
 250                         status = AE_CTRL_PARSE_PENDING;
 251                 }
 252                 return_ACPI_STATUS(status);
 253         }
 254
 255         acpi_ps_append_arg(*op, unnamed_op->common.value.arg);
 256
 257         if ((*op)->common.aml_opcode == AML_REGION_OP ||
 258             (*op)->common.aml_opcode == AML_DATA_REGION_OP) {
 259                 /*
 260                  * Defer final parsing of an operation_region body, because we don't
 261                  * have enough info in the first pass to parse it correctly (i.e.,
 262                  * there may be method calls within the term_arg elements of the body.)
 263                  *
 264                  * However, we must continue parsing because the opregion is not a
 265                  * standalone package -- we don't know where the end is at this point.
 266                  *
 267                  * (Length is unknown until parse of the body complete)
 268                  */
 269                 (*op)->named.data = aml_op_start;
 270                 (*op)->named.length = 0;
 271         }
 272
 273         return_ACPI_STATUS(AE_OK);
 274 }
 275
 276 /*******************************************************************************
 277  *
 278  * FUNCTION:    acpi_ps_create_op
 279  *
 280  * PARAMETERS:  walk_state          - Current state
 281  *              aml_op_start        - Op start in AML
 282  *              new_op              - Returned Op
 283  *
 284  * RETURN:      Status
 285  *
 286  * DESCRIPTION: Get Op from AML
 287  *
 288  ******************************************************************************/
 289
 290 acpi_status
 291 acpi_ps_create_op(struct acpi_walk_state *walk_state,
 292                   u8 *aml_op_start, union acpi_parse_object **new_op)
 293 {
 294         acpi_status status = AE_OK;
 295         union acpi_parse_object *op;
 296         union acpi_parse_object *named_op = NULL;
 297         union acpi_parse_object *parent_scope;
 298         u8 argument_count;
 299         const struct acpi_opcode_info *op_info;
 300
 301         ACPI_FUNCTION_TRACE_PTR(ps_create_op, walk_state);
 302
 303         status = acpi_ps_get_aml_opcode(walk_state);
 304         if (status == AE_CTRL_PARSE_CONTINUE) {
 305                 return_ACPI_STATUS(AE_CTRL_PARSE_CONTINUE);
 306         }
 307         if (ACPI_FAILURE(status)) {
 308                 return_ACPI_STATUS(status);
 309         }
 310
 311         /* Create Op structure and append to parent's argument list */
 312
 313         walk_state->op_info = acpi_ps_get_opcode_info(walk_state->opcode);
 314         op = acpi_ps_alloc_op(walk_state->opcode, aml_op_start);
 315         if (!op) {
 316                 return_ACPI_STATUS(AE_NO_MEMORY);
 317         }
 318
 319         if (walk_state->op_info->flags & AML_NAMED) {
 320                 status =
 321                     acpi_ps_build_named_op(walk_state, aml_op_start, op,
 322                                            &named_op);
 323                 acpi_ps_free_op(op);
 324                 if (ACPI_FAILURE(status)) {
 325                         return_ACPI_STATUS(status);
 326                 }
 327
 328                 *new_op = named_op;
 329                 return_ACPI_STATUS(AE_OK);
 330         }
 331
 332         /* Not a named opcode, just allocate Op and append to parent */
 333
 334         if (walk_state->op_info->flags & AML_CREATE) {
 335                 /*
 336                  * Backup to beginning of create_XXXfield declaration
 337                  * body_length is unknown until we parse the body
 338                  */
 339                 op->named.data = aml_op_start;
 340                 op->named.length = 0;
 341         }
 342
 343         if (walk_state->opcode == AML_BANK_FIELD_OP) {
 344                 /*
 345                  * Backup to beginning of bank_field declaration
 346                  * body_length is unknown until we parse the body
 347                  */
 348                 op->named.data = aml_op_start;
 349                 op->named.length = 0;
 350         }
 351
 352         parent_scope = acpi_ps_get_parent_scope(&(walk_state->parser_state));
 353         acpi_ps_append_arg(parent_scope, op);
 354
 355         if (parent_scope) {
 356                 op_info =
 357                     acpi_ps_get_opcode_info(parent_scope->common.aml_opcode);
 358                 if (op_info->flags & AML_HAS_TARGET) {
 359                         argument_count =
 360                             acpi_ps_get_argument_count(op_info->type);
 361                         if (parent_scope->common.arg_list_length >
 362                             argument_count) {
 363                                 op->common.flags |= ACPI_PARSEOP_TARGET;
 364                         }
 365                 } else if (parent_scope->common.aml_opcode == AML_INCREMENT_OP) {
 366                         op->common.flags |= ACPI_PARSEOP_TARGET;
 367                 }
 368         }
 369
 370         if (walk_state->descending_callback != NULL) {
 371                 /*
 372                  * Find the object. This will either insert the object into
 373                  * the namespace or simply look it up
 374                  */
 375                 walk_state->op = *new_op = op;
 376
 377                 status = walk_state->descending_callback(walk_state, &op);
 378                 status = acpi_ps_next_parse_state(walk_state, op, status);
 379                 if (status == AE_CTRL_PENDING) {
 380                         status = AE_CTRL_PARSE_PENDING;
 381                 }
 382         }
 383
 384         return_ACPI_STATUS(status);
 385 }
 386
 387 /*******************************************************************************
 388  *
 389  * FUNCTION:    acpi_ps_complete_op
 390  *
 391  * PARAMETERS:  walk_state          - Current state
 392  *              op                  - Returned Op
 393  *              status              - Parse status before complete Op
 394  *
 395  * RETURN:      Status
 396  *
 397  * DESCRIPTION: Complete Op
 398  *
 399  ******************************************************************************/
 400
 401 acpi_status
 402 acpi_ps_complete_op(struct acpi_walk_state *walk_state,
 403                     union acpi_parse_object **op, acpi_status status)
 404 {
 405         acpi_status status2;
 406
 407         ACPI_FUNCTION_TRACE_PTR(ps_complete_op, walk_state);
 408
 409         /*
 410          * Finished one argument of the containing scope
 411          */
 412         walk_state->parser_state.scope->parse_scope.arg_count--;
 413
 414         /* Close this Op (will result in parse subtree deletion) */
 415
 416         status2 = acpi_ps_complete_this_op(walk_state, *op);
 417         if (ACPI_FAILURE(status2)) {
 418                 return_ACPI_STATUS(status2);
 419         }
 420
 421         *op = NULL;
 422
 423         switch (status) {
 424         case AE_OK:
 425
 426                 break;
 427
 428         case AE_CTRL_TRANSFER:
 429
 430                 /* We are about to transfer to a called method */
 431
 432                 walk_state->prev_op = NULL;
 433                 walk_state->prev_arg_types = walk_state->arg_types;
 434                 return_ACPI_STATUS(status);
 435
 436         case AE_CTRL_END:
 437
 438                 acpi_ps_pop_scope(&(walk_state->parser_state), op,
 439                                   &walk_state->arg_types,
 440                                   &walk_state->arg_count);
 441
 442                 if (*op) {
 443                         walk_state->op = *op;
 444                         walk_state->op_info =
 445                             acpi_ps_get_opcode_info((*op)->common.aml_opcode);
 446                         walk_state->opcode = (*op)->common.aml_opcode;
 447
 448                         status = walk_state->ascending_callback(walk_state);
 449                         status =
 450                             acpi_ps_next_parse_state(walk_state, *op, status);
 451
 452                         status2 = acpi_ps_complete_this_op(walk_state, *op);
 453                         if (ACPI_FAILURE(status2)) {
 454                                 return_ACPI_STATUS(status2);
 455                         }
 456                 }
 457
 458                 status = AE_OK;
 459                 break;
 460
 461         case AE_CTRL_BREAK:
 462         case AE_CTRL_CONTINUE:
 463
 464                 /* Pop off scopes until we find the While */
 465
 466                 while (!(*op) || ((*op)->common.aml_opcode != AML_WHILE_OP)) {
 467                         acpi_ps_pop_scope(&(walk_state->parser_state), op,
 468                                           &walk_state->arg_types,
 469                                           &walk_state->arg_count);
 470                 }
 471
 472                 /* Close this iteration of the While loop */
 473
 474                 walk_state->op = *op;
 475                 walk_state->op_info =
 476                     acpi_ps_get_opcode_info((*op)->common.aml_opcode);
 477                 walk_state->opcode = (*op)->common.aml_opcode;
 478
 479                 status = walk_state->ascending_callback(walk_state);
 480                 status = acpi_ps_next_parse_state(walk_state, *op, status);
 481
 482                 status2 = acpi_ps_complete_this_op(walk_state, *op);
 483                 if (ACPI_FAILURE(status2)) {
 484                         return_ACPI_STATUS(status2);
 485                 }
 486
 487                 status = AE_OK;
 488                 break;
 489
 490         case AE_CTRL_TERMINATE:
 491
 492                 /* Clean up */
 493                 do {
 494                         if (*op) {
 495                                 status2 =
 496                                     acpi_ps_complete_this_op(walk_state, *op);
 497                                 if (ACPI_FAILURE(status2)) {
 498                                         return_ACPI_STATUS(status2);
 499                                 }
 500
 501                                 acpi_ut_delete_generic_state
 502                                     (acpi_ut_pop_generic_state
 503                                      (&walk_state->control_state));
 504                         }
 505
 506                         acpi_ps_pop_scope(&(walk_state->parser_state), op,
 507                                           &walk_state->arg_types,
 508                                           &walk_state->arg_count);
 509
 510                 } while (*op);
 511
 512                 return_ACPI_STATUS(AE_OK);
 513
 514         default:                /* All other non-AE_OK status */
 515
 516                 do {
 517                         if (*op) {
 518                                 status2 =
 519                                     acpi_ps_complete_this_op(walk_state, *op);
 520                                 if (ACPI_FAILURE(status2)) {
 521                                         return_ACPI_STATUS(status2);
 522                                 }
 523                         }
 524
 525                         acpi_ps_pop_scope(&(walk_state->parser_state), op,
 526                                           &walk_state->arg_types,
 527                                           &walk_state->arg_count);
 528
 529                 } while (*op);
 530
 531 #if 0
 532                 /*
 533                  * TBD: Cleanup parse ops on error
 534                  */
 535                 if (*op == NULL) {
 536                         acpi_ps_pop_scope(parser_state, op,
 537                                           &walk_state->arg_types,
 538                                           &walk_state->arg_count);
 539                 }
 540 #endif
 541                 walk_state->prev_op = NULL;
 542                 walk_state->prev_arg_types = walk_state->arg_types;
 543                 return_ACPI_STATUS(status);
 544         }
 545
 546         /* This scope complete? */
 547
 548         if (acpi_ps_has_completed_scope(&(walk_state->parser_state))) {
 549                 acpi_ps_pop_scope(&(walk_state->parser_state), op,
 550                                   &walk_state->arg_types,
 551                                   &walk_state->arg_count);
 552                 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "Popped scope, Op=%p\n", *op));
 553         } else {
 554                 *op = NULL;
 555         }
 556
 557         return_ACPI_STATUS(AE_OK);
 558 }
 559
 560 /*******************************************************************************
 561  *
 562  * FUNCTION:    acpi_ps_complete_final_op
 563  *
 564  * PARAMETERS:  walk_state          - Current state
 565  *              op                  - Current Op
 566  *              status              - Current parse status before complete last
 567  *                                    Op
 568  *
 569  * RETURN:      Status
 570  *
 571  * DESCRIPTION: Complete last Op.
 572  *
 573  ******************************************************************************/
 574
 575 acpi_status
 576 acpi_ps_complete_final_op(struct acpi_walk_state *walk_state,
 577                           union acpi_parse_object *op, acpi_status status)
 578 {
 579         acpi_status status2;
 580
 581         ACPI_FUNCTION_TRACE_PTR(ps_complete_final_op, walk_state);
 582
 583         /*
 584          * Complete the last Op (if not completed), and clear the scope stack.
 585          * It is easily possible to end an AML "package" with an unbounded number
 586          * of open scopes (such as when several ASL blocks are closed with
 587          * sequential closing braces). We want to terminate each one cleanly.
 588          */
 589         ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "AML package complete at Op %p\n",
 590                           op));
 591         do {
 592                 if (op) {
 593                         if (walk_state->ascending_callback != NULL) {
 594                                 walk_state->op = op;
 595                                 walk_state->op_info =
 596                                     acpi_ps_get_opcode_info(op->common.
 597                                                             aml_opcode);
 598                                 walk_state->opcode = op->common.aml_opcode;
 599
 600                                 status =
 601                                     walk_state->ascending_callback(walk_state);
 602                                 status =
 603                                     acpi_ps_next_parse_state(walk_state, op,
 604                                                              status);
 605                                 if (status == AE_CTRL_PENDING) {
 606                                         status =
 607                                             acpi_ps_complete_op(walk_state, &op,
 608                                                                 AE_OK);
 609                                         if (ACPI_FAILURE(status)) {
 610                                                 return_ACPI_STATUS(status);
 611                                         }
 612                                 }
 613
 614                                 if (status == AE_CTRL_TERMINATE) {
 615                                         status = AE_OK;
 616
 617                                         /* Clean up */
 618                                         do {
 619                                                 if (op) {
 620                                                         status2 =
 621                                                             acpi_ps_complete_this_op
 622                                                             (walk_state, op);
 623                                                         if (ACPI_FAILURE
 624                                                             (status2)) {
 625                                                                 return_ACPI_STATUS
 626                                                                     (status2);
 627                                                         }
 628                                                 }
 629
 630                                                 acpi_ps_pop_scope(&
 631                                                                   (walk_state->
 632                                                                    parser_state),
 633                                                                   &op,
 634                                                                   &walk_state->
 635                                                                   arg_types,
 636                                                                   &walk_state->
 637                                                                   arg_count);
 638
 639                                         } while (op);
 640
 641                                         return_ACPI_STATUS(status);
 642                                 }
 643
 644                                 else if (ACPI_FAILURE(status)) {
 645
 646                                         /* First error is most important */
 647
 648                                         (void)
 649                                             acpi_ps_complete_this_op(walk_state,
 650                                                                      op);
 651                                         return_ACPI_STATUS(status);
 652                                 }
 653                         }
 654
 655                         status2 = acpi_ps_complete_this_op(walk_state, op);
 656                         if (ACPI_FAILURE(status2)) {
 657                                 return_ACPI_STATUS(status2);
 658                         }
 659                 }
 660
 661                 acpi_ps_pop_scope(&(walk_state->parser_state), &op,
 662                                   &walk_state->arg_types,
 663                                   &walk_state->arg_count);
 664
 665         } while (op);
 666
 667         return_ACPI_STATUS(status);
 668 }