git.oblomov.eu Git - linux-2.6/blob - drivers/acpi/dispatcher/dswstate.c

   1 /******************************************************************************
   2  *
   3  * Module Name: dswstate - Dispatcher parse tree walk management routines
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2007, 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/acdispat.h>
  47 #include <acpi/acnamesp.h>
  48
  49 #define _COMPONENT          ACPI_DISPATCHER
  50 ACPI_MODULE_NAME("dswstate")
  51
  52 /* Local prototypes */
  53 #ifdef ACPI_OBSOLETE_FUNCTIONS
  54 acpi_status
  55 acpi_ds_result_insert(void *object,
  56                       u32 index, struct acpi_walk_state *walk_state);
  57
  58 acpi_status acpi_ds_obj_stack_delete_all(struct acpi_walk_state *walk_state);
  59
  60 acpi_status
  61 acpi_ds_obj_stack_pop_object(union acpi_operand_object **object,
  62                              struct acpi_walk_state *walk_state);
  63
  64 void *acpi_ds_obj_stack_get_value(u32 index,
  65                                   struct acpi_walk_state *walk_state);
  66 #endif
  67
  68 #ifdef ACPI_FUTURE_USAGE
  69 /*******************************************************************************
  70  *
  71  * FUNCTION:    acpi_ds_result_remove
  72  *
  73  * PARAMETERS:  Object              - Where to return the popped object
  74  *              Index               - Where to extract the object
  75  *              walk_state          - Current Walk state
  76  *
  77  * RETURN:      Status
  78  *
  79  * DESCRIPTION: Pop an object off the bottom of this walk's result stack.  In
  80  *              other words, this is a FIFO.
  81  *
  82  ******************************************************************************/
  83
  84 acpi_status
  85 acpi_ds_result_remove(union acpi_operand_object **object,
  86                       u32 index, struct acpi_walk_state *walk_state)
  87 {
  88         union acpi_generic_state *state;
  89
  90         ACPI_FUNCTION_NAME(ds_result_remove);
  91
  92         state = walk_state->results;
  93         if (!state) {
  94                 ACPI_ERROR((AE_INFO, "No result object pushed! State=%p",
  95                             walk_state));
  96                 return (AE_NOT_EXIST);
  97         }
  98
  99         if (index >= ACPI_OBJ_MAX_OPERAND) {
 100                 ACPI_ERROR((AE_INFO,
 101                             "Index out of range: %X State=%p Num=%X",
 102                             index, walk_state, state->results.num_results));
 103         }
 104
 105         /* Check for a valid result object */
 106
 107         if (!state->results.obj_desc[index]) {
 108                 ACPI_ERROR((AE_INFO,
 109                             "Null operand! State=%p #Ops=%X, Index=%X",
 110                             walk_state, state->results.num_results, index));
 111                 return (AE_AML_NO_RETURN_VALUE);
 112         }
 113
 114         /* Remove the object */
 115
 116         state->results.num_results--;
 117
 118         *object = state->results.obj_desc[index];
 119         state->results.obj_desc[index] = NULL;
 120
 121         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 122                           "Obj=%p [%s] Index=%X State=%p Num=%X\n",
 123                           *object,
 124                           (*object) ? acpi_ut_get_object_type_name(*object) :
 125                           "NULL", index, walk_state,
 126                           state->results.num_results));
 127
 128         return (AE_OK);
 129 }
 130 #endif                          /*  ACPI_FUTURE_USAGE  */
 131
 132 /*******************************************************************************
 133  *
 134  * FUNCTION:    acpi_ds_result_pop
 135  *
 136  * PARAMETERS:  Object              - Where to return the popped object
 137  *              walk_state          - Current Walk state
 138  *
 139  * RETURN:      Status
 140  *
 141  * DESCRIPTION: Pop an object off the bottom of this walk's result stack.  In
 142  *              other words, this is a FIFO.
 143  *
 144  ******************************************************************************/
 145
 146 acpi_status
 147 acpi_ds_result_pop(union acpi_operand_object ** object,
 148                    struct acpi_walk_state * walk_state)
 149 {
 150         acpi_native_uint index;
 151         union acpi_generic_state *state;
 152
 153         ACPI_FUNCTION_NAME(ds_result_pop);
 154
 155         state = walk_state->results;
 156         if (!state) {
 157                 return (AE_OK);
 158         }
 159
 160         if (!state->results.num_results) {
 161                 ACPI_ERROR((AE_INFO, "Result stack is empty! State=%p",
 162                             walk_state));
 163                 return (AE_AML_NO_RETURN_VALUE);
 164         }
 165
 166         /* Remove top element */
 167
 168         state->results.num_results--;
 169
 170         for (index = ACPI_OBJ_NUM_OPERANDS; index; index--) {
 171
 172                 /* Check for a valid result object */
 173
 174                 if (state->results.obj_desc[index - 1]) {
 175                         *object = state->results.obj_desc[index - 1];
 176                         state->results.obj_desc[index - 1] = NULL;
 177
 178                         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 179                                           "Obj=%p [%s] Index=%X State=%p Num=%X\n",
 180                                           *object,
 181                                           (*object) ?
 182                                           acpi_ut_get_object_type_name(*object)
 183                                           : "NULL", (u32) index - 1, walk_state,
 184                                           state->results.num_results));
 185
 186                         return (AE_OK);
 187                 }
 188         }
 189
 190         ACPI_ERROR((AE_INFO, "No result objects! State=%p", walk_state));
 191         return (AE_AML_NO_RETURN_VALUE);
 192 }
 193
 194 /*******************************************************************************
 195  *
 196  * FUNCTION:    acpi_ds_result_pop_from_bottom
 197  *
 198  * PARAMETERS:  Object              - Where to return the popped object
 199  *              walk_state          - Current Walk state
 200  *
 201  * RETURN:      Status
 202  *
 203  * DESCRIPTION: Pop an object off the bottom of this walk's result stack.  In
 204  *              other words, this is a FIFO.
 205  *
 206  ******************************************************************************/
 207
 208 acpi_status
 209 acpi_ds_result_pop_from_bottom(union acpi_operand_object ** object,
 210                                struct acpi_walk_state * walk_state)
 211 {
 212         acpi_native_uint index;
 213         union acpi_generic_state *state;
 214
 215         ACPI_FUNCTION_NAME(ds_result_pop_from_bottom);
 216
 217         state = walk_state->results;
 218         if (!state) {
 219                 ACPI_ERROR((AE_INFO,
 220                             "No result object pushed! State=%p", walk_state));
 221                 return (AE_NOT_EXIST);
 222         }
 223
 224         if (!state->results.num_results) {
 225                 ACPI_ERROR((AE_INFO, "No result objects! State=%p",
 226                             walk_state));
 227                 return (AE_AML_NO_RETURN_VALUE);
 228         }
 229
 230         /* Remove Bottom element */
 231
 232         *object = state->results.obj_desc[0];
 233
 234         /* Push entire stack down one element */
 235
 236         for (index = 0; index < state->results.num_results; index++) {
 237                 state->results.obj_desc[index] =
 238                     state->results.obj_desc[index + 1];
 239         }
 240
 241         state->results.num_results--;
 242
 243         /* Check for a valid result object */
 244
 245         if (!*object) {
 246                 ACPI_ERROR((AE_INFO,
 247                             "Null operand! State=%p #Ops=%X Index=%X",
 248                             walk_state, state->results.num_results,
 249                             (u32) index));
 250                 return (AE_AML_NO_RETURN_VALUE);
 251         }
 252
 253         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] Results=%p State=%p\n",
 254                           *object,
 255                           (*object) ? acpi_ut_get_object_type_name(*object) :
 256                           "NULL", state, walk_state));
 257
 258         return (AE_OK);
 259 }
 260
 261 /*******************************************************************************
 262  *
 263  * FUNCTION:    acpi_ds_result_push
 264  *
 265  * PARAMETERS:  Object              - Where to return the popped object
 266  *              walk_state          - Current Walk state
 267  *
 268  * RETURN:      Status
 269  *
 270  * DESCRIPTION: Push an object onto the current result stack
 271  *
 272  ******************************************************************************/
 273
 274 acpi_status
 275 acpi_ds_result_push(union acpi_operand_object * object,
 276                     struct acpi_walk_state * walk_state)
 277 {
 278         union acpi_generic_state *state;
 279
 280         ACPI_FUNCTION_NAME(ds_result_push);
 281
 282         state = walk_state->results;
 283         if (!state) {
 284                 ACPI_ERROR((AE_INFO, "No result stack frame during push"));
 285                 return (AE_AML_INTERNAL);
 286         }
 287
 288         if (state->results.num_results == ACPI_OBJ_NUM_OPERANDS) {
 289                 ACPI_ERROR((AE_INFO,
 290                             "Result stack overflow: Obj=%p State=%p Num=%X",
 291                             object, walk_state, state->results.num_results));
 292                 return (AE_STACK_OVERFLOW);
 293         }
 294
 295         if (!object) {
 296                 ACPI_ERROR((AE_INFO,
 297                             "Null Object! Obj=%p State=%p Num=%X",
 298                             object, walk_state, state->results.num_results));
 299                 return (AE_BAD_PARAMETER);
 300         }
 301
 302         state->results.obj_desc[state->results.num_results] = object;
 303         state->results.num_results++;
 304
 305         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p Num=%X Cur=%X\n",
 306                           object,
 307                           object ?
 308                           acpi_ut_get_object_type_name((union
 309                                                         acpi_operand_object *)
 310                                                        object) : "NULL",
 311                           walk_state, state->results.num_results,
 312                           walk_state->current_result));
 313
 314         return (AE_OK);
 315 }
 316
 317 /*******************************************************************************
 318  *
 319  * FUNCTION:    acpi_ds_result_stack_push
 320  *
 321  * PARAMETERS:  walk_state          - Current Walk state
 322  *
 323  * RETURN:      Status
 324  *
 325  * DESCRIPTION: Push an object onto the walk_state result stack.
 326  *
 327  ******************************************************************************/
 328
 329 acpi_status acpi_ds_result_stack_push(struct acpi_walk_state * walk_state)
 330 {
 331         union acpi_generic_state *state;
 332
 333         ACPI_FUNCTION_NAME(ds_result_stack_push);
 334
 335         state = acpi_ut_create_generic_state();
 336         if (!state) {
 337                 return (AE_NO_MEMORY);
 338         }
 339
 340         state->common.descriptor_type = ACPI_DESC_TYPE_STATE_RESULT;
 341         acpi_ut_push_generic_state(&walk_state->results, state);
 342
 343         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Results=%p State=%p\n",
 344                           state, walk_state));
 345
 346         return (AE_OK);
 347 }
 348
 349 /*******************************************************************************
 350  *
 351  * FUNCTION:    acpi_ds_result_stack_pop
 352  *
 353  * PARAMETERS:  walk_state          - Current Walk state
 354  *
 355  * RETURN:      Status
 356  *
 357  * DESCRIPTION: Pop an object off of the walk_state result stack.
 358  *
 359  ******************************************************************************/
 360
 361 acpi_status acpi_ds_result_stack_pop(struct acpi_walk_state * walk_state)
 362 {
 363         union acpi_generic_state *state;
 364
 365         ACPI_FUNCTION_NAME(ds_result_stack_pop);
 366
 367         /* Check for stack underflow */
 368
 369         if (walk_state->results == NULL) {
 370                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Underflow - State=%p\n",
 371                                   walk_state));
 372                 return (AE_AML_NO_OPERAND);
 373         }
 374
 375         state = acpi_ut_pop_generic_state(&walk_state->results);
 376
 377         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 378                           "Result=%p RemainingResults=%X State=%p\n",
 379                           state, state->results.num_results, walk_state));
 380
 381         acpi_ut_delete_generic_state(state);
 382
 383         return (AE_OK);
 384 }
 385
 386 /*******************************************************************************
 387  *
 388  * FUNCTION:    acpi_ds_obj_stack_push
 389  *
 390  * PARAMETERS:  Object              - Object to push
 391  *              walk_state          - Current Walk state
 392  *
 393  * RETURN:      Status
 394  *
 395  * DESCRIPTION: Push an object onto this walk's object/operand stack
 396  *
 397  ******************************************************************************/
 398
 399 acpi_status
 400 acpi_ds_obj_stack_push(void *object, struct acpi_walk_state * walk_state)
 401 {
 402         ACPI_FUNCTION_NAME(ds_obj_stack_push);
 403
 404         /* Check for stack overflow */
 405
 406         if (walk_state->num_operands >= ACPI_OBJ_NUM_OPERANDS) {
 407                 ACPI_ERROR((AE_INFO,
 408                             "Object stack overflow! Obj=%p State=%p #Ops=%X",
 409                             object, walk_state, walk_state->num_operands));
 410                 return (AE_STACK_OVERFLOW);
 411         }
 412
 413         /* Put the object onto the stack */
 414
 415         walk_state->operands[walk_state->num_operands] = object;
 416         walk_state->num_operands++;
 417
 418         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p #Ops=%X\n",
 419                           object,
 420                           acpi_ut_get_object_type_name((union
 421                                                         acpi_operand_object *)
 422                                                        object), walk_state,
 423                           walk_state->num_operands));
 424
 425         return (AE_OK);
 426 }
 427
 428 /*******************************************************************************
 429  *
 430  * FUNCTION:    acpi_ds_obj_stack_pop
 431  *
 432  * PARAMETERS:  pop_count           - Number of objects/entries to pop
 433  *              walk_state          - Current Walk state
 434  *
 435  * RETURN:      Status
 436  *
 437  * DESCRIPTION: Pop this walk's object stack.  Objects on the stack are NOT
 438  *              deleted by this routine.
 439  *
 440  ******************************************************************************/
 441
 442 acpi_status
 443 acpi_ds_obj_stack_pop(u32 pop_count, struct acpi_walk_state * walk_state)
 444 {
 445         u32 i;
 446
 447         ACPI_FUNCTION_NAME(ds_obj_stack_pop);
 448
 449         for (i = 0; i < pop_count; i++) {
 450
 451                 /* Check for stack underflow */
 452
 453                 if (walk_state->num_operands == 0) {
 454                         ACPI_ERROR((AE_INFO,
 455                                     "Object stack underflow! Count=%X State=%p #Ops=%X",
 456                                     pop_count, walk_state,
 457                                     walk_state->num_operands));
 458                         return (AE_STACK_UNDERFLOW);
 459                 }
 460
 461                 /* Just set the stack entry to null */
 462
 463                 walk_state->num_operands--;
 464                 walk_state->operands[walk_state->num_operands] = NULL;
 465         }
 466
 467         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%X\n",
 468                           pop_count, walk_state, walk_state->num_operands));
 469
 470         return (AE_OK);
 471 }
 472
 473 /*******************************************************************************
 474  *
 475  * FUNCTION:    acpi_ds_obj_stack_pop_and_delete
 476  *
 477  * PARAMETERS:  pop_count           - Number of objects/entries to pop
 478  *              walk_state          - Current Walk state
 479  *
 480  * RETURN:      Status
 481  *
 482  * DESCRIPTION: Pop this walk's object stack and delete each object that is
 483  *              popped off.
 484  *
 485  ******************************************************************************/
 486
 487 acpi_status
 488 acpi_ds_obj_stack_pop_and_delete(u32 pop_count,
 489                                  struct acpi_walk_state * walk_state)
 490 {
 491         u32 i;
 492         union acpi_operand_object *obj_desc;
 493
 494         ACPI_FUNCTION_NAME(ds_obj_stack_pop_and_delete);
 495
 496         for (i = 0; i < pop_count; i++) {
 497
 498                 /* Check for stack underflow */
 499
 500                 if (walk_state->num_operands == 0) {
 501                         ACPI_ERROR((AE_INFO,
 502                                     "Object stack underflow! Count=%X State=%p #Ops=%X",
 503                                     pop_count, walk_state,
 504                                     walk_state->num_operands));
 505                         return (AE_STACK_UNDERFLOW);
 506                 }
 507
 508                 /* Pop the stack and delete an object if present in this stack entry */
 509
 510                 walk_state->num_operands--;
 511                 obj_desc = walk_state->operands[walk_state->num_operands];
 512                 if (obj_desc) {
 513                         acpi_ut_remove_reference(walk_state->
 514                                                  operands[walk_state->
 515                                                           num_operands]);
 516                         walk_state->operands[walk_state->num_operands] = NULL;
 517                 }
 518         }
 519
 520         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%X\n",
 521                           pop_count, walk_state, walk_state->num_operands));
 522
 523         return (AE_OK);
 524 }
 525
 526 /*******************************************************************************
 527  *
 528  * FUNCTION:    acpi_ds_get_current_walk_state
 529  *
 530  * PARAMETERS:  Thread          - Get current active state for this Thread
 531  *
 532  * RETURN:      Pointer to the current walk state
 533  *
 534  * DESCRIPTION: Get the walk state that is at the head of the list (the "current"
 535  *              walk state.)
 536  *
 537  ******************************************************************************/
 538
 539 struct acpi_walk_state *acpi_ds_get_current_walk_state(struct acpi_thread_state
 540                                                        *thread)
 541 {
 542         ACPI_FUNCTION_NAME(ds_get_current_walk_state);
 543
 544         if (!thread) {
 545                 return (NULL);
 546         }
 547
 548         ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "Current WalkState %p\n",
 549                           thread->walk_state_list));
 550
 551         return (thread->walk_state_list);
 552 }
 553
 554 /*******************************************************************************
 555  *
 556  * FUNCTION:    acpi_ds_push_walk_state
 557  *
 558  * PARAMETERS:  walk_state      - State to push
 559  *              Thread          - Thread state object
 560  *
 561  * RETURN:      None
 562  *
 563  * DESCRIPTION: Place the Thread state at the head of the state list.
 564  *
 565  ******************************************************************************/
 566
 567 void
 568 acpi_ds_push_walk_state(struct acpi_walk_state *walk_state,
 569                         struct acpi_thread_state *thread)
 570 {
 571         ACPI_FUNCTION_TRACE(ds_push_walk_state);
 572
 573         walk_state->next = thread->walk_state_list;
 574         thread->walk_state_list = walk_state;
 575
 576         return_VOID;
 577 }
 578
 579 /*******************************************************************************
 580  *
 581  * FUNCTION:    acpi_ds_pop_walk_state
 582  *
 583  * PARAMETERS:  Thread      - Current thread state
 584  *
 585  * RETURN:      A walk_state object popped from the thread's stack
 586  *
 587  * DESCRIPTION: Remove and return the walkstate object that is at the head of
 588  *              the walk stack for the given walk list.  NULL indicates that
 589  *              the list is empty.
 590  *
 591  ******************************************************************************/
 592
 593 struct acpi_walk_state *acpi_ds_pop_walk_state(struct acpi_thread_state *thread)
 594 {
 595         struct acpi_walk_state *walk_state;
 596
 597         ACPI_FUNCTION_TRACE(ds_pop_walk_state);
 598
 599         walk_state = thread->walk_state_list;
 600
 601         if (walk_state) {
 602
 603                 /* Next walk state becomes the current walk state */
 604
 605                 thread->walk_state_list = walk_state->next;
 606
 607                 /*
 608                  * Don't clear the NEXT field, this serves as an indicator
 609                  * that there is a parent WALK STATE
 610                  * Do Not: walk_state->Next = NULL;
 611                  */
 612         }
 613
 614         return_PTR(walk_state);
 615 }
 616
 617 /*******************************************************************************
 618  *
 619  * FUNCTION:    acpi_ds_create_walk_state
 620  *
 621  * PARAMETERS:  owner_id        - ID for object creation
 622  *              Origin          - Starting point for this walk
 623  *              method_desc     - Method object
 624  *              Thread          - Current thread state
 625  *
 626  * RETURN:      Pointer to the new walk state.
 627  *
 628  * DESCRIPTION: Allocate and initialize a new walk state.  The current walk
 629  *              state is set to this new state.
 630  *
 631  ******************************************************************************/
 632
 633 struct acpi_walk_state *acpi_ds_create_walk_state(acpi_owner_id owner_id,
 634                                                   union acpi_parse_object
 635                                                   *origin,
 636                                                   union acpi_operand_object
 637                                                   *method_desc,
 638                                                   struct acpi_thread_state
 639                                                   *thread)
 640 {
 641         struct acpi_walk_state *walk_state;
 642         acpi_status status;
 643
 644         ACPI_FUNCTION_TRACE(ds_create_walk_state);
 645
 646         walk_state = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_walk_state));
 647         if (!walk_state) {
 648                 return_PTR(NULL);
 649         }
 650
 651         walk_state->descriptor_type = ACPI_DESC_TYPE_WALK;
 652         walk_state->method_desc = method_desc;
 653         walk_state->owner_id = owner_id;
 654         walk_state->origin = origin;
 655         walk_state->thread = thread;
 656
 657         walk_state->parser_state.start_op = origin;
 658
 659         /* Init the method args/local */
 660
 661 #if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))
 662         acpi_ds_method_data_init(walk_state);
 663 #endif
 664
 665         /* Create an initial result stack entry */
 666
 667         status = acpi_ds_result_stack_push(walk_state);
 668         if (ACPI_FAILURE(status)) {
 669                 ACPI_FREE(walk_state);
 670                 return_PTR(NULL);
 671         }
 672
 673         /* Put the new state at the head of the walk list */
 674
 675         if (thread) {
 676                 acpi_ds_push_walk_state(walk_state, thread);
 677         }
 678
 679         return_PTR(walk_state);
 680 }
 681
 682 /*******************************************************************************
 683  *
 684  * FUNCTION:    acpi_ds_init_aml_walk
 685  *
 686  * PARAMETERS:  walk_state      - New state to be initialized
 687  *              Op              - Current parse op
 688  *              method_node     - Control method NS node, if any
 689  *              aml_start       - Start of AML
 690  *              aml_length      - Length of AML
 691  *              Info            - Method info block (params, etc.)
 692  *              pass_number     - 1, 2, or 3
 693  *
 694  * RETURN:      Status
 695  *
 696  * DESCRIPTION: Initialize a walk state for a pass 1 or 2 parse tree walk
 697  *
 698  ******************************************************************************/
 699
 700 acpi_status
 701 acpi_ds_init_aml_walk(struct acpi_walk_state *walk_state,
 702                       union acpi_parse_object *op,
 703                       struct acpi_namespace_node *method_node,
 704                       u8 * aml_start,
 705                       u32 aml_length,
 706                       struct acpi_evaluate_info *info, u8 pass_number)
 707 {
 708         acpi_status status;
 709         struct acpi_parse_state *parser_state = &walk_state->parser_state;
 710         union acpi_parse_object *extra_op;
 711
 712         ACPI_FUNCTION_TRACE(ds_init_aml_walk);
 713
 714         walk_state->parser_state.aml =
 715             walk_state->parser_state.aml_start = aml_start;
 716         walk_state->parser_state.aml_end =
 717             walk_state->parser_state.pkg_end = aml_start + aml_length;
 718
 719         /* The next_op of the next_walk will be the beginning of the method */
 720
 721         walk_state->next_op = NULL;
 722         walk_state->pass_number = pass_number;
 723
 724         if (info) {
 725                 if (info->parameter_type == ACPI_PARAM_GPE) {
 726                         walk_state->gpe_event_info =
 727                             ACPI_CAST_PTR(struct acpi_gpe_event_info,
 728                                           info->parameters);
 729                 } else {
 730                         walk_state->params = info->parameters;
 731                         walk_state->caller_return_desc = &info->return_object;
 732                 }
 733         }
 734
 735         status = acpi_ps_init_scope(&walk_state->parser_state, op);
 736         if (ACPI_FAILURE(status)) {
 737                 return_ACPI_STATUS(status);
 738         }
 739
 740         if (method_node) {
 741                 walk_state->parser_state.start_node = method_node;
 742                 walk_state->walk_type = ACPI_WALK_METHOD;
 743                 walk_state->method_node = method_node;
 744                 walk_state->method_desc =
 745                     acpi_ns_get_attached_object(method_node);
 746
 747                 /* Push start scope on scope stack and make it current  */
 748
 749                 status =
 750                     acpi_ds_scope_stack_push(method_node, ACPI_TYPE_METHOD,
 751                                              walk_state);
 752                 if (ACPI_FAILURE(status)) {
 753                         return_ACPI_STATUS(status);
 754                 }
 755
 756                 /* Init the method arguments */
 757
 758                 status = acpi_ds_method_data_init_args(walk_state->params,
 759                                                        ACPI_METHOD_NUM_ARGS,
 760                                                        walk_state);
 761                 if (ACPI_FAILURE(status)) {
 762                         return_ACPI_STATUS(status);
 763                 }
 764         } else {
 765                 /*
 766                  * Setup the current scope.
 767                  * Find a Named Op that has a namespace node associated with it.
 768                  * search upwards from this Op.  Current scope is the first
 769                  * Op with a namespace node.
 770                  */
 771                 extra_op = parser_state->start_op;
 772                 while (extra_op && !extra_op->common.node) {
 773                         extra_op = extra_op->common.parent;
 774                 }
 775
 776                 if (!extra_op) {
 777                         parser_state->start_node = NULL;
 778                 } else {
 779                         parser_state->start_node = extra_op->common.node;
 780                 }
 781
 782                 if (parser_state->start_node) {
 783
 784                         /* Push start scope on scope stack and make it current  */
 785
 786                         status =
 787                             acpi_ds_scope_stack_push(parser_state->start_node,
 788                                                      parser_state->start_node->
 789                                                      type, walk_state);
 790                         if (ACPI_FAILURE(status)) {
 791                                 return_ACPI_STATUS(status);
 792                         }
 793                 }
 794         }
 795
 796         status = acpi_ds_init_callbacks(walk_state, pass_number);
 797         return_ACPI_STATUS(status);
 798 }
 799
 800 /*******************************************************************************
 801  *
 802  * FUNCTION:    acpi_ds_delete_walk_state
 803  *
 804  * PARAMETERS:  walk_state      - State to delete
 805  *
 806  * RETURN:      Status
 807  *
 808  * DESCRIPTION: Delete a walk state including all internal data structures
 809  *
 810  ******************************************************************************/
 811
 812 void acpi_ds_delete_walk_state(struct acpi_walk_state *walk_state)
 813 {
 814         union acpi_generic_state *state;
 815
 816         ACPI_FUNCTION_TRACE_PTR(ds_delete_walk_state, walk_state);
 817
 818         if (!walk_state) {
 819                 return;
 820         }
 821
 822         if (walk_state->descriptor_type != ACPI_DESC_TYPE_WALK) {
 823                 ACPI_ERROR((AE_INFO, "%p is not a valid walk state",
 824                             walk_state));
 825                 return;
 826         }
 827
 828         /* There should not be any open scopes */
 829
 830         if (walk_state->parser_state.scope) {
 831                 ACPI_ERROR((AE_INFO, "%p walk still has a scope list",
 832                             walk_state));
 833                 acpi_ps_cleanup_scope(&walk_state->parser_state);
 834         }
 835
 836         /* Always must free any linked control states */
 837
 838         while (walk_state->control_state) {
 839                 state = walk_state->control_state;
 840                 walk_state->control_state = state->common.next;
 841
 842                 acpi_ut_delete_generic_state(state);
 843         }
 844
 845         /* Always must free any linked parse states */
 846
 847         while (walk_state->scope_info) {
 848                 state = walk_state->scope_info;
 849                 walk_state->scope_info = state->common.next;
 850
 851                 acpi_ut_delete_generic_state(state);
 852         }
 853
 854         /* Always must free any stacked result states */
 855
 856         while (walk_state->results) {
 857                 state = walk_state->results;
 858                 walk_state->results = state->common.next;
 859
 860                 acpi_ut_delete_generic_state(state);
 861         }
 862
 863         ACPI_FREE(walk_state);
 864         return_VOID;
 865 }
 866
 867 #ifdef ACPI_OBSOLETE_FUNCTIONS
 868 /*******************************************************************************
 869  *
 870  * FUNCTION:    acpi_ds_result_insert
 871  *
 872  * PARAMETERS:  Object              - Object to push
 873  *              Index               - Where to insert the object
 874  *              walk_state          - Current Walk state
 875  *
 876  * RETURN:      Status
 877  *
 878  * DESCRIPTION: Insert an object onto this walk's result stack
 879  *
 880  ******************************************************************************/
 881
 882 acpi_status
 883 acpi_ds_result_insert(void *object,
 884                       u32 index, struct acpi_walk_state *walk_state)
 885 {
 886         union acpi_generic_state *state;
 887
 888         ACPI_FUNCTION_NAME(ds_result_insert);
 889
 890         state = walk_state->results;
 891         if (!state) {
 892                 ACPI_ERROR((AE_INFO, "No result object pushed! State=%p",
 893                             walk_state));
 894                 return (AE_NOT_EXIST);
 895         }
 896
 897         if (index >= ACPI_OBJ_NUM_OPERANDS) {
 898                 ACPI_ERROR((AE_INFO,
 899                             "Index out of range: %X Obj=%p State=%p Num=%X",
 900                             index, object, walk_state,
 901                             state->results.num_results));
 902                 return (AE_BAD_PARAMETER);
 903         }
 904
 905         if (!object) {
 906                 ACPI_ERROR((AE_INFO,
 907                             "Null Object! Index=%X Obj=%p State=%p Num=%X",
 908                             index, object, walk_state,
 909                             state->results.num_results));
 910                 return (AE_BAD_PARAMETER);
 911         }
 912
 913         state->results.obj_desc[index] = object;
 914         state->results.num_results++;
 915
 916         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 917                           "Obj=%p [%s] State=%p Num=%X Cur=%X\n",
 918                           object,
 919                           object ?
 920                           acpi_ut_get_object_type_name((union
 921                                                         acpi_operand_object *)
 922                                                        object) : "NULL",
 923                           walk_state, state->results.num_results,
 924                           walk_state->current_result));
 925
 926         return (AE_OK);
 927 }
 928
 929 /*******************************************************************************
 930  *
 931  * FUNCTION:    acpi_ds_obj_stack_delete_all
 932  *
 933  * PARAMETERS:  walk_state          - Current Walk state
 934  *
 935  * RETURN:      Status
 936  *
 937  * DESCRIPTION: Clear the object stack by deleting all objects that are on it.
 938  *              Should be used with great care, if at all!
 939  *
 940  ******************************************************************************/
 941
 942 acpi_status acpi_ds_obj_stack_delete_all(struct acpi_walk_state * walk_state)
 943 {
 944         u32 i;
 945
 946         ACPI_FUNCTION_TRACE_PTR(ds_obj_stack_delete_all, walk_state);
 947
 948         /* The stack size is configurable, but fixed */
 949
 950         for (i = 0; i < ACPI_OBJ_NUM_OPERANDS; i++) {
 951                 if (walk_state->operands[i]) {
 952                         acpi_ut_remove_reference(walk_state->operands[i]);
 953                         walk_state->operands[i] = NULL;
 954                 }
 955         }
 956
 957         return_ACPI_STATUS(AE_OK);
 958 }
 959
 960 /*******************************************************************************
 961  *
 962  * FUNCTION:    acpi_ds_obj_stack_pop_object
 963  *
 964  * PARAMETERS:  Object              - Where to return the popped object
 965  *              walk_state          - Current Walk state
 966  *
 967  * RETURN:      Status
 968  *
 969  * DESCRIPTION: Pop this walk's object stack.  Objects on the stack are NOT
 970  *              deleted by this routine.
 971  *
 972  ******************************************************************************/
 973
 974 acpi_status
 975 acpi_ds_obj_stack_pop_object(union acpi_operand_object **object,
 976                              struct acpi_walk_state *walk_state)
 977 {
 978         ACPI_FUNCTION_NAME(ds_obj_stack_pop_object);
 979
 980         /* Check for stack underflow */
 981
 982         if (walk_state->num_operands == 0) {
 983                 ACPI_ERROR((AE_INFO,
 984                             "Missing operand/stack empty! State=%p #Ops=%X",
 985                             walk_state, walk_state->num_operands));
 986                 *object = NULL;
 987                 return (AE_AML_NO_OPERAND);
 988         }
 989
 990         /* Pop the stack */
 991
 992         walk_state->num_operands--;
 993
 994         /* Check for a valid operand */
 995
 996         if (!walk_state->operands[walk_state->num_operands]) {
 997                 ACPI_ERROR((AE_INFO,
 998                             "Null operand! State=%p #Ops=%X",
 999                             walk_state, walk_state->num_operands));
1000                 *object = NULL;
1001                 return (AE_AML_NO_OPERAND);
1002         }
1003
1004         /* Get operand and set stack entry to null */
1005
1006         *object = walk_state->operands[walk_state->num_operands];
1007         walk_state->operands[walk_state->num_operands] = NULL;
1008
1009         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p #Ops=%X\n",
1010                           *object, acpi_ut_get_object_type_name(*object),
1011                           walk_state, walk_state->num_operands));
1012
1013         return (AE_OK);
1014 }
1015
1016 /*******************************************************************************
1017  *
1018  * FUNCTION:    acpi_ds_obj_stack_get_value
1019  *
1020  * PARAMETERS:  Index               - Stack index whose value is desired.  Based
1021  *                                    on the top of the stack (index=0 == top)
1022  *              walk_state          - Current Walk state
1023  *
1024  * RETURN:      Pointer to the requested operand
1025  *
1026  * DESCRIPTION: Retrieve an object from this walk's operand stack.  Index must
1027  *              be within the range of the current stack pointer.
1028  *
1029  ******************************************************************************/
1030
1031 void *acpi_ds_obj_stack_get_value(u32 index, struct acpi_walk_state *walk_state)
1032 {
1033
1034         ACPI_FUNCTION_TRACE_PTR(ds_obj_stack_get_value, walk_state);
1035
1036         /* Can't do it if the stack is empty */
1037
1038         if (walk_state->num_operands == 0) {
1039                 return_PTR(NULL);
1040         }
1041
1042         /* or if the index is past the top of the stack */
1043
1044         if (index > (walk_state->num_operands - (u32) 1)) {
1045                 return_PTR(NULL);
1046         }
1047
1048         return_PTR(walk_state->
1049                    operands[(acpi_native_uint) (walk_state->num_operands - 1) -
1050                             index]);
1051 }
1052 #endif