[ACPI] ACPICA 20060113
[linux-2.6] / 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 - 2006, 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  *
72  * FUNCTION:    acpi_ds_result_remove
73  *
74  * PARAMETERS:  Object              - Where to return the popped object
75  *              Index               - Where to extract the object
76  *              walk_state          - Current Walk state
77  *
78  * RETURN:      Status
79  *
80  * DESCRIPTION: Pop an object off the bottom of this walk's result stack.  In
81  *              other words, this is a FIFO.
82  *
83  ******************************************************************************/
84
85 acpi_status
86 acpi_ds_result_remove(union acpi_operand_object **object,
87                       u32 index, struct acpi_walk_state *walk_state)
88 {
89         union acpi_generic_state *state;
90
91         ACPI_FUNCTION_NAME("ds_result_remove");
92
93         state = walk_state->results;
94         if (!state) {
95                 ACPI_REPORT_ERROR(("No result object pushed! State=%p\n",
96                                    walk_state));
97                 return (AE_NOT_EXIST);
98         }
99
100         if (index >= ACPI_OBJ_MAX_OPERAND) {
101                 ACPI_REPORT_ERROR(("Index out of range: %X State=%p Num=%X\n",
102                                    index, walk_state,
103                                    state->results.num_results));
104         }
105
106         /* Check for a valid result object */
107
108         if (!state->results.obj_desc[index]) {
109                 ACPI_REPORT_ERROR(("Null operand! State=%p #Ops=%X, Index=%X\n",
110                                    walk_state, state->results.num_results,
111                                    index));
112                 return (AE_AML_NO_RETURN_VALUE);
113         }
114
115         /* Remove the object */
116
117         state->results.num_results--;
118
119         *object = state->results.obj_desc[index];
120         state->results.obj_desc[index] = NULL;
121
122         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
123                           "Obj=%p [%s] Index=%X State=%p Num=%X\n",
124                           *object,
125                           (*object) ? acpi_ut_get_object_type_name(*object) :
126                           "NULL", index, walk_state,
127                           state->results.num_results));
128
129         return (AE_OK);
130 }
131
132 #endif                          /*  ACPI_FUTURE_USAGE  */
133
134 /*******************************************************************************
135  *
136  * FUNCTION:    acpi_ds_result_pop
137  *
138  * PARAMETERS:  Object              - Where to return the popped object
139  *              walk_state          - Current Walk state
140  *
141  * RETURN:      Status
142  *
143  * DESCRIPTION: Pop an object off the bottom of this walk's result stack.  In
144  *              other words, this is a FIFO.
145  *
146  ******************************************************************************/
147
148 acpi_status
149 acpi_ds_result_pop(union acpi_operand_object ** object,
150                    struct acpi_walk_state * walk_state)
151 {
152         acpi_native_uint index;
153         union acpi_generic_state *state;
154
155         ACPI_FUNCTION_NAME("ds_result_pop");
156
157         state = walk_state->results;
158         if (!state) {
159                 return (AE_OK);
160         }
161
162         if (!state->results.num_results) {
163                 ACPI_REPORT_ERROR(("Result stack is empty! State=%p\n",
164                                    walk_state));
165                 return (AE_AML_NO_RETURN_VALUE);
166         }
167
168         /* Remove top element */
169
170         state->results.num_results--;
171
172         for (index = ACPI_OBJ_NUM_OPERANDS; index; index--) {
173                 /* Check for a valid result object */
174
175                 if (state->results.obj_desc[index - 1]) {
176                         *object = state->results.obj_desc[index - 1];
177                         state->results.obj_desc[index - 1] = NULL;
178
179                         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
180                                           "Obj=%p [%s] Index=%X State=%p Num=%X\n",
181                                           *object,
182                                           (*object) ?
183                                           acpi_ut_get_object_type_name(*object)
184                                           : "NULL", (u32) index - 1, walk_state,
185                                           state->results.num_results));
186
187                         return (AE_OK);
188                 }
189         }
190
191         ACPI_REPORT_ERROR(("No result objects! State=%p\n", walk_state));
192         return (AE_AML_NO_RETURN_VALUE);
193 }
194
195 /*******************************************************************************
196  *
197  * FUNCTION:    acpi_ds_result_pop_from_bottom
198  *
199  * PARAMETERS:  Object              - Where to return the popped object
200  *              walk_state          - Current Walk state
201  *
202  * RETURN:      Status
203  *
204  * DESCRIPTION: Pop an object off the bottom of this walk's result stack.  In
205  *              other words, this is a FIFO.
206  *
207  ******************************************************************************/
208
209 acpi_status
210 acpi_ds_result_pop_from_bottom(union acpi_operand_object ** object,
211                                struct acpi_walk_state * walk_state)
212 {
213         acpi_native_uint index;
214         union acpi_generic_state *state;
215
216         ACPI_FUNCTION_NAME("ds_result_pop_from_bottom");
217
218         state = walk_state->results;
219         if (!state) {
220                 ACPI_REPORT_ERROR(("No result object pushed! State=%p\n",
221                                    walk_state));
222                 return (AE_NOT_EXIST);
223         }
224
225         if (!state->results.num_results) {
226                 ACPI_REPORT_ERROR(("No result objects! State=%p\n",
227                                    walk_state));
228                 return (AE_AML_NO_RETURN_VALUE);
229         }
230
231         /* Remove Bottom element */
232
233         *object = state->results.obj_desc[0];
234
235         /* Push entire stack down one element */
236
237         for (index = 0; index < state->results.num_results; index++) {
238                 state->results.obj_desc[index] =
239                     state->results.obj_desc[index + 1];
240         }
241
242         state->results.num_results--;
243
244         /* Check for a valid result object */
245
246         if (!*object) {
247                 ACPI_REPORT_ERROR(("Null operand! State=%p #Ops=%X Index=%X\n",
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_REPORT_ERROR(("No result stack frame during push\n"));
285                 return (AE_AML_INTERNAL);
286         }
287
288         if (state->results.num_results == ACPI_OBJ_NUM_OPERANDS) {
289                 ACPI_REPORT_ERROR(("Result stack overflow: Obj=%p State=%p Num=%X\n", object, walk_state, state->results.num_results));
290                 return (AE_STACK_OVERFLOW);
291         }
292
293         if (!object) {
294                 ACPI_REPORT_ERROR(("Null Object! Obj=%p State=%p Num=%X\n",
295                                    object, walk_state,
296                                    state->results.num_results));
297                 return (AE_BAD_PARAMETER);
298         }
299
300         state->results.obj_desc[state->results.num_results] = object;
301         state->results.num_results++;
302
303         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p Num=%X Cur=%X\n",
304                           object,
305                           object ?
306                           acpi_ut_get_object_type_name((union
307                                                         acpi_operand_object *)
308                                                        object) : "NULL",
309                           walk_state, state->results.num_results,
310                           walk_state->current_result));
311
312         return (AE_OK);
313 }
314
315 /*******************************************************************************
316  *
317  * FUNCTION:    acpi_ds_result_stack_push
318  *
319  * PARAMETERS:  walk_state          - Current Walk state
320  *
321  * RETURN:      Status
322  *
323  * DESCRIPTION: Push an object onto the walk_state result stack.
324  *
325  ******************************************************************************/
326
327 acpi_status acpi_ds_result_stack_push(struct acpi_walk_state * walk_state)
328 {
329         union acpi_generic_state *state;
330
331         ACPI_FUNCTION_NAME("ds_result_stack_push");
332
333         state = acpi_ut_create_generic_state();
334         if (!state) {
335                 return (AE_NO_MEMORY);
336         }
337
338         state->common.data_type = ACPI_DESC_TYPE_STATE_RESULT;
339         acpi_ut_push_generic_state(&walk_state->results, state);
340
341         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Results=%p State=%p\n",
342                           state, walk_state));
343
344         return (AE_OK);
345 }
346
347 /*******************************************************************************
348  *
349  * FUNCTION:    acpi_ds_result_stack_pop
350  *
351  * PARAMETERS:  walk_state          - Current Walk state
352  *
353  * RETURN:      Status
354  *
355  * DESCRIPTION: Pop an object off of the walk_state result stack.
356  *
357  ******************************************************************************/
358
359 acpi_status acpi_ds_result_stack_pop(struct acpi_walk_state * walk_state)
360 {
361         union acpi_generic_state *state;
362
363         ACPI_FUNCTION_NAME("ds_result_stack_pop");
364
365         /* Check for stack underflow */
366
367         if (walk_state->results == NULL) {
368                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Underflow - State=%p\n",
369                                   walk_state));
370                 return (AE_AML_NO_OPERAND);
371         }
372
373         state = acpi_ut_pop_generic_state(&walk_state->results);
374
375         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
376                           "Result=%p remaining_results=%X State=%p\n",
377                           state, state->results.num_results, walk_state));
378
379         acpi_ut_delete_generic_state(state);
380
381         return (AE_OK);
382 }
383
384 /*******************************************************************************
385  *
386  * FUNCTION:    acpi_ds_obj_stack_push
387  *
388  * PARAMETERS:  Object              - Object to push
389  *              walk_state          - Current Walk state
390  *
391  * RETURN:      Status
392  *
393  * DESCRIPTION: Push an object onto this walk's object/operand stack
394  *
395  ******************************************************************************/
396
397 acpi_status
398 acpi_ds_obj_stack_push(void *object, struct acpi_walk_state * walk_state)
399 {
400         ACPI_FUNCTION_NAME("ds_obj_stack_push");
401
402         /* Check for stack overflow */
403
404         if (walk_state->num_operands >= ACPI_OBJ_NUM_OPERANDS) {
405                 ACPI_REPORT_ERROR(("Object stack overflow! Obj=%p State=%p #Ops=%X\n", object, walk_state, walk_state->num_operands));
406                 return (AE_STACK_OVERFLOW);
407         }
408
409         /* Put the object onto the stack */
410
411         walk_state->operands[walk_state->num_operands] = object;
412         walk_state->num_operands++;
413
414         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p #Ops=%X\n",
415                           object,
416                           acpi_ut_get_object_type_name((union
417                                                         acpi_operand_object *)
418                                                        object), walk_state,
419                           walk_state->num_operands));
420
421         return (AE_OK);
422 }
423
424 /*******************************************************************************
425  *
426  * FUNCTION:    acpi_ds_obj_stack_pop
427  *
428  * PARAMETERS:  pop_count           - Number of objects/entries to pop
429  *              walk_state          - Current Walk state
430  *
431  * RETURN:      Status
432  *
433  * DESCRIPTION: Pop this walk's object stack.  Objects on the stack are NOT
434  *              deleted by this routine.
435  *
436  ******************************************************************************/
437
438 acpi_status
439 acpi_ds_obj_stack_pop(u32 pop_count, struct acpi_walk_state * walk_state)
440 {
441         u32 i;
442
443         ACPI_FUNCTION_NAME("ds_obj_stack_pop");
444
445         for (i = 0; i < pop_count; i++) {
446                 /* Check for stack underflow */
447
448                 if (walk_state->num_operands == 0) {
449                         ACPI_REPORT_ERROR(("Object stack underflow! Count=%X State=%p #Ops=%X\n", pop_count, walk_state, walk_state->num_operands));
450                         return (AE_STACK_UNDERFLOW);
451                 }
452
453                 /* Just set the stack entry to null */
454
455                 walk_state->num_operands--;
456                 walk_state->operands[walk_state->num_operands] = NULL;
457         }
458
459         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%X\n",
460                           pop_count, walk_state, walk_state->num_operands));
461
462         return (AE_OK);
463 }
464
465 /*******************************************************************************
466  *
467  * FUNCTION:    acpi_ds_obj_stack_pop_and_delete
468  *
469  * PARAMETERS:  pop_count           - Number of objects/entries to pop
470  *              walk_state          - Current Walk state
471  *
472  * RETURN:      Status
473  *
474  * DESCRIPTION: Pop this walk's object stack and delete each object that is
475  *              popped off.
476  *
477  ******************************************************************************/
478
479 acpi_status
480 acpi_ds_obj_stack_pop_and_delete(u32 pop_count,
481                                  struct acpi_walk_state * walk_state)
482 {
483         u32 i;
484         union acpi_operand_object *obj_desc;
485
486         ACPI_FUNCTION_NAME("ds_obj_stack_pop_and_delete");
487
488         for (i = 0; i < pop_count; i++) {
489                 /* Check for stack underflow */
490
491                 if (walk_state->num_operands == 0) {
492                         ACPI_REPORT_ERROR(("Object stack underflow! Count=%X State=%p #Ops=%X\n", pop_count, walk_state, walk_state->num_operands));
493                         return (AE_STACK_UNDERFLOW);
494                 }
495
496                 /* Pop the stack and delete an object if present in this stack entry */
497
498                 walk_state->num_operands--;
499                 obj_desc = walk_state->operands[walk_state->num_operands];
500                 if (obj_desc) {
501                         acpi_ut_remove_reference(walk_state->
502                                                  operands[walk_state->
503                                                           num_operands]);
504                         walk_state->operands[walk_state->num_operands] = NULL;
505                 }
506         }
507
508         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%X\n",
509                           pop_count, walk_state, walk_state->num_operands));
510
511         return (AE_OK);
512 }
513
514 /*******************************************************************************
515  *
516  * FUNCTION:    acpi_ds_get_current_walk_state
517  *
518  * PARAMETERS:  Thread          - Get current active state for this Thread
519  *
520  * RETURN:      Pointer to the current walk state
521  *
522  * DESCRIPTION: Get the walk state that is at the head of the list (the "current"
523  *              walk state.)
524  *
525  ******************************************************************************/
526
527 struct acpi_walk_state *acpi_ds_get_current_walk_state(struct acpi_thread_state
528                                                        *thread)
529 {
530         ACPI_FUNCTION_NAME("ds_get_current_walk_state");
531
532         if (!thread) {
533                 return (NULL);
534         }
535
536         ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "Current walk_state %p\n",
537                           thread->walk_state_list));
538
539         return (thread->walk_state_list);
540 }
541
542 /*******************************************************************************
543  *
544  * FUNCTION:    acpi_ds_push_walk_state
545  *
546  * PARAMETERS:  walk_state      - State to push
547  *              Thread          - Thread state object
548  *
549  * RETURN:      None
550  *
551  * DESCRIPTION: Place the Thread state at the head of the state list.
552  *
553  ******************************************************************************/
554
555 void
556 acpi_ds_push_walk_state(struct acpi_walk_state *walk_state,
557                         struct acpi_thread_state *thread)
558 {
559         ACPI_FUNCTION_TRACE("ds_push_walk_state");
560
561         walk_state->next = thread->walk_state_list;
562         thread->walk_state_list = walk_state;
563
564         return_VOID;
565 }
566
567 /*******************************************************************************
568  *
569  * FUNCTION:    acpi_ds_pop_walk_state
570  *
571  * PARAMETERS:  Thread      - Current thread state
572  *
573  * RETURN:      A walk_state object popped from the thread's stack
574  *
575  * DESCRIPTION: Remove and return the walkstate object that is at the head of
576  *              the walk stack for the given walk list.  NULL indicates that
577  *              the list is empty.
578  *
579  ******************************************************************************/
580
581 struct acpi_walk_state *acpi_ds_pop_walk_state(struct acpi_thread_state *thread)
582 {
583         struct acpi_walk_state *walk_state;
584
585         ACPI_FUNCTION_TRACE("ds_pop_walk_state");
586
587         walk_state = thread->walk_state_list;
588
589         if (walk_state) {
590                 /* Next walk state becomes the current walk state */
591
592                 thread->walk_state_list = walk_state->next;
593
594                 /*
595                  * Don't clear the NEXT field, this serves as an indicator
596                  * that there is a parent WALK STATE
597                  * Do Not: walk_state->Next = NULL;
598                  */
599         }
600
601         return_PTR(walk_state);
602 }
603
604 /*******************************************************************************
605  *
606  * FUNCTION:    acpi_ds_create_walk_state
607  *
608  * PARAMETERS:  owner_id        - ID for object creation
609  *              Origin          - Starting point for this walk
610  *              mth_desc        - Method object
611  *              Thread          - Current thread state
612  *
613  * RETURN:      Pointer to the new walk state.
614  *
615  * DESCRIPTION: Allocate and initialize a new walk state.  The current walk
616  *              state is set to this new state.
617  *
618  ******************************************************************************/
619
620 struct acpi_walk_state *acpi_ds_create_walk_state(acpi_owner_id owner_id,
621                                                   union acpi_parse_object
622                                                   *origin,
623                                                   union acpi_operand_object
624                                                   *mth_desc,
625                                                   struct acpi_thread_state
626                                                   *thread)
627 {
628         struct acpi_walk_state *walk_state;
629         acpi_status status;
630
631         ACPI_FUNCTION_TRACE("ds_create_walk_state");
632
633         walk_state = ACPI_MEM_CALLOCATE(sizeof(struct acpi_walk_state));
634         if (!walk_state) {
635                 return_PTR(NULL);
636         }
637
638         walk_state->data_type = ACPI_DESC_TYPE_WALK;
639         walk_state->owner_id = owner_id;
640         walk_state->origin = origin;
641         walk_state->method_desc = mth_desc;
642         walk_state->thread = thread;
643
644         walk_state->parser_state.start_op = origin;
645
646         /* Init the method args/local */
647
648 #if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))
649         acpi_ds_method_data_init(walk_state);
650 #endif
651
652         /* Create an initial result stack entry */
653
654         status = acpi_ds_result_stack_push(walk_state);
655         if (ACPI_FAILURE(status)) {
656                 ACPI_MEM_FREE(walk_state);
657                 return_PTR(NULL);
658         }
659
660         /* Put the new state at the head of the walk list */
661
662         if (thread) {
663                 acpi_ds_push_walk_state(walk_state, thread);
664         }
665
666         return_PTR(walk_state);
667 }
668
669 /*******************************************************************************
670  *
671  * FUNCTION:    acpi_ds_init_aml_walk
672  *
673  * PARAMETERS:  walk_state      - New state to be initialized
674  *              Op              - Current parse op
675  *              method_node     - Control method NS node, if any
676  *              aml_start       - Start of AML
677  *              aml_length      - Length of AML
678  *              Info            - Method info block (params, etc.)
679  *              pass_number     - 1, 2, or 3
680  *
681  * RETURN:      Status
682  *
683  * DESCRIPTION: Initialize a walk state for a pass 1 or 2 parse tree walk
684  *
685  ******************************************************************************/
686
687 acpi_status
688 acpi_ds_init_aml_walk(struct acpi_walk_state *walk_state,
689                       union acpi_parse_object *op,
690                       struct acpi_namespace_node *method_node,
691                       u8 * aml_start,
692                       u32 aml_length,
693                       struct acpi_parameter_info *info, u8 pass_number)
694 {
695         acpi_status status;
696         struct acpi_parse_state *parser_state = &walk_state->parser_state;
697         union acpi_parse_object *extra_op;
698
699         ACPI_FUNCTION_TRACE("ds_init_aml_walk");
700
701         walk_state->parser_state.aml =
702             walk_state->parser_state.aml_start = aml_start;
703         walk_state->parser_state.aml_end =
704             walk_state->parser_state.pkg_end = aml_start + aml_length;
705
706         /* The next_op of the next_walk will be the beginning of the method */
707
708         walk_state->next_op = NULL;
709         walk_state->pass_number = pass_number;
710
711         if (info) {
712                 if (info->parameter_type == ACPI_PARAM_GPE) {
713                         walk_state->gpe_event_info =
714                             ACPI_CAST_PTR(struct acpi_gpe_event_info,
715                                           info->parameters);
716                 } else {
717                         walk_state->params = info->parameters;
718                         walk_state->caller_return_desc = &info->return_object;
719                 }
720         }
721
722         status = acpi_ps_init_scope(&walk_state->parser_state, op);
723         if (ACPI_FAILURE(status)) {
724                 return_ACPI_STATUS(status);
725         }
726
727         if (method_node) {
728                 walk_state->parser_state.start_node = method_node;
729                 walk_state->walk_type = ACPI_WALK_METHOD;
730                 walk_state->method_node = method_node;
731                 walk_state->method_desc =
732                     acpi_ns_get_attached_object(method_node);
733
734                 /* Push start scope on scope stack and make it current  */
735
736                 status =
737                     acpi_ds_scope_stack_push(method_node, ACPI_TYPE_METHOD,
738                                              walk_state);
739                 if (ACPI_FAILURE(status)) {
740                         return_ACPI_STATUS(status);
741                 }
742
743                 /* Init the method arguments */
744
745                 status = acpi_ds_method_data_init_args(walk_state->params,
746                                                        ACPI_METHOD_NUM_ARGS,
747                                                        walk_state);
748                 if (ACPI_FAILURE(status)) {
749                         return_ACPI_STATUS(status);
750                 }
751         } else {
752                 /*
753                  * Setup the current scope.
754                  * Find a Named Op that has a namespace node associated with it.
755                  * search upwards from this Op.  Current scope is the first
756                  * Op with a namespace node.
757                  */
758                 extra_op = parser_state->start_op;
759                 while (extra_op && !extra_op->common.node) {
760                         extra_op = extra_op->common.parent;
761                 }
762
763                 if (!extra_op) {
764                         parser_state->start_node = NULL;
765                 } else {
766                         parser_state->start_node = extra_op->common.node;
767                 }
768
769                 if (parser_state->start_node) {
770                         /* Push start scope on scope stack and make it current  */
771
772                         status =
773                             acpi_ds_scope_stack_push(parser_state->start_node,
774                                                      parser_state->start_node->
775                                                      type, walk_state);
776                         if (ACPI_FAILURE(status)) {
777                                 return_ACPI_STATUS(status);
778                         }
779                 }
780         }
781
782         status = acpi_ds_init_callbacks(walk_state, pass_number);
783         return_ACPI_STATUS(status);
784 }
785
786 /*******************************************************************************
787  *
788  * FUNCTION:    acpi_ds_delete_walk_state
789  *
790  * PARAMETERS:  walk_state      - State to delete
791  *
792  * RETURN:      Status
793  *
794  * DESCRIPTION: Delete a walk state including all internal data structures
795  *
796  ******************************************************************************/
797
798 void acpi_ds_delete_walk_state(struct acpi_walk_state *walk_state)
799 {
800         union acpi_generic_state *state;
801
802         ACPI_FUNCTION_TRACE_PTR("ds_delete_walk_state", walk_state);
803
804         if (!walk_state) {
805                 return;
806         }
807
808         if (walk_state->data_type != ACPI_DESC_TYPE_WALK) {
809                 ACPI_REPORT_ERROR(("%p is not a valid walk state\n",
810                                    walk_state));
811                 return;
812         }
813
814         if (walk_state->parser_state.scope) {
815                 ACPI_REPORT_ERROR(("%p walk still has a scope list\n",
816                                    walk_state));
817         }
818
819         /* Always must free any linked control states */
820
821         while (walk_state->control_state) {
822                 state = walk_state->control_state;
823                 walk_state->control_state = state->common.next;
824
825                 acpi_ut_delete_generic_state(state);
826         }
827
828         /* Always must free any linked parse states */
829
830         while (walk_state->scope_info) {
831                 state = walk_state->scope_info;
832                 walk_state->scope_info = state->common.next;
833
834                 acpi_ut_delete_generic_state(state);
835         }
836
837         /* Always must free any stacked result states */
838
839         while (walk_state->results) {
840                 state = walk_state->results;
841                 walk_state->results = state->common.next;
842
843                 acpi_ut_delete_generic_state(state);
844         }
845
846         ACPI_MEM_FREE(walk_state);
847         return_VOID;
848 }
849
850 #ifdef ACPI_OBSOLETE_FUNCTIONS
851 /*******************************************************************************
852  *
853  * FUNCTION:    acpi_ds_result_insert
854  *
855  * PARAMETERS:  Object              - Object to push
856  *              Index               - Where to insert the object
857  *              walk_state          - Current Walk state
858  *
859  * RETURN:      Status
860  *
861  * DESCRIPTION: Insert an object onto this walk's result stack
862  *
863  ******************************************************************************/
864
865 acpi_status
866 acpi_ds_result_insert(void *object,
867                       u32 index, struct acpi_walk_state *walk_state)
868 {
869         union acpi_generic_state *state;
870
871         ACPI_FUNCTION_NAME("ds_result_insert");
872
873         state = walk_state->results;
874         if (!state) {
875                 ACPI_REPORT_ERROR(("No result object pushed! State=%p\n",
876                                    walk_state));
877                 return (AE_NOT_EXIST);
878         }
879
880         if (index >= ACPI_OBJ_NUM_OPERANDS) {
881                 ACPI_REPORT_ERROR(("Index out of range: %X Obj=%p State=%p Num=%X\n", index, object, walk_state, state->results.num_results));
882                 return (AE_BAD_PARAMETER);
883         }
884
885         if (!object) {
886                 ACPI_REPORT_ERROR(("Null Object! Index=%X Obj=%p State=%p Num=%X\n", index, object, walk_state, state->results.num_results));
887                 return (AE_BAD_PARAMETER);
888         }
889
890         state->results.obj_desc[index] = object;
891         state->results.num_results++;
892
893         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
894                           "Obj=%p [%s] State=%p Num=%X Cur=%X\n",
895                           object,
896                           object ?
897                           acpi_ut_get_object_type_name((union
898                                                         acpi_operand_object *)
899                                                        object) : "NULL",
900                           walk_state, state->results.num_results,
901                           walk_state->current_result));
902
903         return (AE_OK);
904 }
905
906 /*******************************************************************************
907  *
908  * FUNCTION:    acpi_ds_obj_stack_delete_all
909  *
910  * PARAMETERS:  walk_state          - Current Walk state
911  *
912  * RETURN:      Status
913  *
914  * DESCRIPTION: Clear the object stack by deleting all objects that are on it.
915  *              Should be used with great care, if at all!
916  *
917  ******************************************************************************/
918
919 acpi_status acpi_ds_obj_stack_delete_all(struct acpi_walk_state * walk_state)
920 {
921         u32 i;
922
923         ACPI_FUNCTION_TRACE_PTR("ds_obj_stack_delete_all", walk_state);
924
925         /* The stack size is configurable, but fixed */
926
927         for (i = 0; i < ACPI_OBJ_NUM_OPERANDS; i++) {
928                 if (walk_state->operands[i]) {
929                         acpi_ut_remove_reference(walk_state->operands[i]);
930                         walk_state->operands[i] = NULL;
931                 }
932         }
933
934         return_ACPI_STATUS(AE_OK);
935 }
936
937 /*******************************************************************************
938  *
939  * FUNCTION:    acpi_ds_obj_stack_pop_object
940  *
941  * PARAMETERS:  Object              - Where to return the popped object
942  *              walk_state          - Current Walk state
943  *
944  * RETURN:      Status
945  *
946  * DESCRIPTION: Pop this walk's object stack.  Objects on the stack are NOT
947  *              deleted by this routine.
948  *
949  ******************************************************************************/
950
951 acpi_status
952 acpi_ds_obj_stack_pop_object(union acpi_operand_object **object,
953                              struct acpi_walk_state *walk_state)
954 {
955         ACPI_FUNCTION_NAME("ds_obj_stack_pop_object");
956
957         /* Check for stack underflow */
958
959         if (walk_state->num_operands == 0) {
960                 ACPI_REPORT_ERROR(("Missing operand/stack empty! State=%p #Ops=%X\n", walk_state, walk_state->num_operands));
961                 *object = NULL;
962                 return (AE_AML_NO_OPERAND);
963         }
964
965         /* Pop the stack */
966
967         walk_state->num_operands--;
968
969         /* Check for a valid operand */
970
971         if (!walk_state->operands[walk_state->num_operands]) {
972                 ACPI_REPORT_ERROR(("Null operand! State=%p #Ops=%X\n",
973                                    walk_state, walk_state->num_operands));
974                 *object = NULL;
975                 return (AE_AML_NO_OPERAND);
976         }
977
978         /* Get operand and set stack entry to null */
979
980         *object = walk_state->operands[walk_state->num_operands];
981         walk_state->operands[walk_state->num_operands] = NULL;
982
983         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p #Ops=%X\n",
984                           *object, acpi_ut_get_object_type_name(*object),
985                           walk_state, walk_state->num_operands));
986
987         return (AE_OK);
988 }
989
990 /*******************************************************************************
991  *
992  * FUNCTION:    acpi_ds_obj_stack_get_value
993  *
994  * PARAMETERS:  Index               - Stack index whose value is desired.  Based
995  *                                    on the top of the stack (index=0 == top)
996  *              walk_state          - Current Walk state
997  *
998  * RETURN:      Pointer to the requested operand
999  *
1000  * DESCRIPTION: Retrieve an object from this walk's operand stack.  Index must
1001  *              be within the range of the current stack pointer.
1002  *
1003  ******************************************************************************/
1004
1005 void *acpi_ds_obj_stack_get_value(u32 index, struct acpi_walk_state *walk_state)
1006 {
1007
1008         ACPI_FUNCTION_TRACE_PTR("ds_obj_stack_get_value", walk_state);
1009
1010         /* Can't do it if the stack is empty */
1011
1012         if (walk_state->num_operands == 0) {
1013                 return_PTR(NULL);
1014         }
1015
1016         /* or if the index is past the top of the stack */
1017
1018         if (index > (walk_state->num_operands - (u32) 1)) {
1019                 return_PTR(NULL);
1020         }
1021
1022         return_PTR(walk_state->
1023                    operands[(acpi_native_uint) (walk_state->num_operands - 1) -
1024                             index]);
1025 }
1026 #endif