ftp://ftp.kernel.org/pub/linux/kernel/v2.6/linux-2.6.6.tar.bz2
[linux-2.6.git] / 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 - 2004, 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
45 #include <acpi/acpi.h>
46 #include <acpi/acparser.h>
47 #include <acpi/acdispat.h>
48 #include <acpi/acnamesp.h>
49
50 #define _COMPONENT          ACPI_DISPATCHER
51          ACPI_MODULE_NAME    ("dswstate")
52
53
54 /*******************************************************************************
55  *
56  * FUNCTION:    acpi_ds_result_insert
57  *
58  * PARAMETERS:  Object              - Object to push
59  *              Index               - Where to insert the object
60  *              walk_state          - Current Walk state
61  *
62  * RETURN:      Status
63  *
64  * DESCRIPTION: Insert an object onto this walk's result stack
65  *
66  ******************************************************************************/
67
68 acpi_status
69 acpi_ds_result_insert (
70         void                            *object,
71         u32                             index,
72         struct acpi_walk_state          *walk_state)
73 {
74         union acpi_generic_state        *state;
75
76
77         ACPI_FUNCTION_NAME ("ds_result_insert");
78
79
80         state = walk_state->results;
81         if (!state) {
82                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "No result object pushed! State=%p\n",
83                         walk_state));
84                 return (AE_NOT_EXIST);
85         }
86
87         if (index >= ACPI_OBJ_NUM_OPERANDS) {
88                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
89                         "Index out of range: %X Obj=%p State=%p Num=%X\n",
90                         index, object, walk_state, state->results.num_results));
91                 return (AE_BAD_PARAMETER);
92         }
93
94         if (!object) {
95                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
96                         "Null Object! Index=%X Obj=%p State=%p Num=%X\n",
97                         index, object, walk_state, state->results.num_results));
98                 return (AE_BAD_PARAMETER);
99         }
100
101         state->results.obj_desc [index] = object;
102         state->results.num_results++;
103
104         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
105                 "Obj=%p [%s] State=%p Num=%X Cur=%X\n",
106                 object, object ? acpi_ut_get_object_type_name ((union acpi_operand_object *) object) : "NULL",
107                 walk_state, state->results.num_results, walk_state->current_result));
108
109         return (AE_OK);
110 }
111
112
113 /*******************************************************************************
114  *
115  * FUNCTION:    acpi_ds_result_remove
116  *
117  * PARAMETERS:  Object              - Where to return the popped object
118  *              Index               - Where to extract the object
119  *              walk_state          - Current Walk state
120  *
121  * RETURN:      Status
122  *
123  * DESCRIPTION: Pop an object off the bottom of this walk's result stack.  In
124  *              other words, this is a FIFO.
125  *
126  ******************************************************************************/
127
128 acpi_status
129 acpi_ds_result_remove (
130         union acpi_operand_object       **object,
131         u32                             index,
132         struct acpi_walk_state          *walk_state)
133 {
134         union acpi_generic_state        *state;
135
136
137         ACPI_FUNCTION_NAME ("ds_result_remove");
138
139
140         state = walk_state->results;
141         if (!state) {
142                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "No result object pushed! State=%p\n",
143                         walk_state));
144                 return (AE_NOT_EXIST);
145         }
146
147         if (index >= ACPI_OBJ_MAX_OPERAND) {
148                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
149                         "Index out of range: %X State=%p Num=%X\n",
150                         index, walk_state, state->results.num_results));
151         }
152
153         /* Check for a valid result object */
154
155         if (!state->results.obj_desc [index]) {
156                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
157                         "Null operand! State=%p #Ops=%X, Index=%X\n",
158                         walk_state, state->results.num_results, index));
159                 return (AE_AML_NO_RETURN_VALUE);
160         }
161
162         /* Remove the object */
163
164         state->results.num_results--;
165
166         *object = state->results.obj_desc [index];
167         state->results.obj_desc [index] = NULL;
168
169         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
170                 "Obj=%p [%s] Index=%X State=%p Num=%X\n",
171                 *object, (*object) ? acpi_ut_get_object_type_name (*object) : "NULL",
172                 index, walk_state, state->results.num_results));
173
174         return (AE_OK);
175 }
176
177
178 /*******************************************************************************
179  *
180  * FUNCTION:    acpi_ds_result_pop
181  *
182  * PARAMETERS:  Object              - Where to return the popped object
183  *              walk_state          - Current Walk state
184  *
185  * RETURN:      Status
186  *
187  * DESCRIPTION: Pop an object off the bottom of this walk's result stack.  In
188  *              other words, this is a FIFO.
189  *
190  ******************************************************************************/
191
192 acpi_status
193 acpi_ds_result_pop (
194         union acpi_operand_object       **object,
195         struct acpi_walk_state          *walk_state)
196 {
197         acpi_native_uint                index;
198         union acpi_generic_state        *state;
199
200
201         ACPI_FUNCTION_NAME ("ds_result_pop");
202
203
204         state = walk_state->results;
205         if (!state) {
206                 return (AE_OK);
207         }
208
209         if (!state->results.num_results) {
210                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Result stack is empty! State=%p\n",
211                         walk_state));
212                 return (AE_AML_NO_RETURN_VALUE);
213         }
214
215         /* Remove top element */
216
217         state->results.num_results--;
218
219         for (index = ACPI_OBJ_NUM_OPERANDS; index; index--) {
220                 /* Check for a valid result object */
221
222                 if (state->results.obj_desc [index -1]) {
223                         *object = state->results.obj_desc [index -1];
224                         state->results.obj_desc [index -1] = NULL;
225
226                         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Obj=%p [%s] Index=%X State=%p Num=%X\n",
227                                 *object, (*object) ? acpi_ut_get_object_type_name (*object) : "NULL",
228                                 (u32) index -1, walk_state, state->results.num_results));
229
230                         return (AE_OK);
231                 }
232         }
233
234         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "No result objects! State=%p\n", walk_state));
235         return (AE_AML_NO_RETURN_VALUE);
236 }
237
238
239 /*******************************************************************************
240  *
241  * FUNCTION:    acpi_ds_result_pop_from_bottom
242  *
243  * PARAMETERS:  Object              - Where to return the popped object
244  *              walk_state          - Current Walk state
245  *
246  * RETURN:      Status
247  *
248  * DESCRIPTION: Pop an object off the bottom of this walk's result stack.  In
249  *              other words, this is a FIFO.
250  *
251  ******************************************************************************/
252
253 acpi_status
254 acpi_ds_result_pop_from_bottom (
255         union acpi_operand_object       **object,
256         struct acpi_walk_state          *walk_state)
257 {
258         acpi_native_uint                index;
259         union acpi_generic_state        *state;
260
261
262         ACPI_FUNCTION_NAME ("ds_result_pop_from_bottom");
263
264
265         state = walk_state->results;
266         if (!state) {
267                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
268                         "Warning: No result object pushed! State=%p\n", walk_state));
269                 return (AE_NOT_EXIST);
270         }
271
272         if (!state->results.num_results) {
273                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "No result objects! State=%p\n", walk_state));
274                 return (AE_AML_NO_RETURN_VALUE);
275         }
276
277         /* Remove Bottom element */
278
279         *object = state->results.obj_desc [0];
280
281         /* Push entire stack down one element */
282
283         for (index = 0; index < state->results.num_results; index++) {
284                 state->results.obj_desc [index] = state->results.obj_desc [index + 1];
285         }
286
287         state->results.num_results--;
288
289         /* Check for a valid result object */
290
291         if (!*object) {
292                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Null operand! State=%p #Ops=%X, Index=%X\n",
293                         walk_state, state->results.num_results, (u32) index));
294                 return (AE_AML_NO_RETURN_VALUE);
295         }
296
297         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Obj=%p [%s], Results=%p State=%p\n",
298                 *object, (*object) ? acpi_ut_get_object_type_name (*object) : "NULL",
299                 state, walk_state));
300
301         return (AE_OK);
302 }
303
304
305 /*******************************************************************************
306  *
307  * FUNCTION:    acpi_ds_result_push
308  *
309  * PARAMETERS:  Object              - Where to return the popped object
310  *              walk_state          - Current Walk state
311  *
312  * RETURN:      Status
313  *
314  * DESCRIPTION: Push an object onto the current result stack
315  *
316  ******************************************************************************/
317
318 acpi_status
319 acpi_ds_result_push (
320         union acpi_operand_object       *object,
321         struct acpi_walk_state          *walk_state)
322 {
323         union acpi_generic_state        *state;
324
325
326         ACPI_FUNCTION_NAME ("ds_result_push");
327
328
329         state = walk_state->results;
330         if (!state) {
331                 ACPI_REPORT_ERROR (("No result stack frame during push\n"));
332                 return (AE_AML_INTERNAL);
333         }
334
335         if (state->results.num_results == ACPI_OBJ_NUM_OPERANDS) {
336                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
337                         "Result stack overflow: Obj=%p State=%p Num=%X\n",
338                         object, walk_state, state->results.num_results));
339                 return (AE_STACK_OVERFLOW);
340         }
341
342         if (!object) {
343                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Null Object! Obj=%p State=%p Num=%X\n",
344                         object, walk_state, state->results.num_results));
345                 return (AE_BAD_PARAMETER);
346         }
347
348         state->results.obj_desc [state->results.num_results] = object;
349         state->results.num_results++;
350
351         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Obj=%p [%s] State=%p Num=%X Cur=%X\n",
352                 object, object ? acpi_ut_get_object_type_name ((union acpi_operand_object *) object) : "NULL",
353                 walk_state, state->results.num_results, walk_state->current_result));
354
355         return (AE_OK);
356 }
357
358
359 /*******************************************************************************
360  *
361  * FUNCTION:    acpi_ds_result_stack_push
362  *
363  * PARAMETERS:  walk_state          - Current Walk state
364  *
365  * RETURN:      Status
366  *
367  * DESCRIPTION: Push an object onto the walk_state result stack.
368  *
369  ******************************************************************************/
370
371 acpi_status
372 acpi_ds_result_stack_push (
373         struct acpi_walk_state          *walk_state)
374 {
375         union acpi_generic_state        *state;
376
377         ACPI_FUNCTION_NAME ("ds_result_stack_push");
378
379
380         state = acpi_ut_create_generic_state ();
381         if (!state) {
382                 return (AE_NO_MEMORY);
383         }
384
385         state->common.data_type = ACPI_DESC_TYPE_STATE_RESULT;
386         acpi_ut_push_generic_state (&walk_state->results, state);
387
388         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Results=%p State=%p\n",
389                 state, walk_state));
390
391         return (AE_OK);
392 }
393
394
395 /*******************************************************************************
396  *
397  * FUNCTION:    acpi_ds_result_stack_pop
398  *
399  * PARAMETERS:  walk_state          - Current Walk state
400  *
401  * RETURN:      Status
402  *
403  * DESCRIPTION: Pop an object off of the walk_state result stack.
404  *
405  ******************************************************************************/
406
407 acpi_status
408 acpi_ds_result_stack_pop (
409         struct acpi_walk_state          *walk_state)
410 {
411         union acpi_generic_state        *state;
412
413         ACPI_FUNCTION_NAME ("ds_result_stack_pop");
414
415
416         /* Check for stack underflow */
417
418         if (walk_state->results == NULL) {
419                 ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Underflow - State=%p\n",
420                         walk_state));
421                 return (AE_AML_NO_OPERAND);
422         }
423
424         state = acpi_ut_pop_generic_state (&walk_state->results);
425
426         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
427                 "Result=%p remaining_results=%X State=%p\n",
428                 state, state->results.num_results, walk_state));
429
430         acpi_ut_delete_generic_state (state);
431
432         return (AE_OK);
433 }
434
435
436 /*******************************************************************************
437  *
438  * FUNCTION:    acpi_ds_obj_stack_delete_all
439  *
440  * PARAMETERS:  walk_state          - Current Walk state
441  *
442  * RETURN:      Status
443  *
444  * DESCRIPTION: Clear the object stack by deleting all objects that are on it.
445  *              Should be used with great care, if at all!
446  *
447  ******************************************************************************/
448
449 acpi_status
450 acpi_ds_obj_stack_delete_all (
451         struct acpi_walk_state          *walk_state)
452 {
453         u32                             i;
454
455
456         ACPI_FUNCTION_TRACE_PTR ("ds_obj_stack_delete_all", walk_state);
457
458
459         /* The stack size is configurable, but fixed */
460
461         for (i = 0; i < ACPI_OBJ_NUM_OPERANDS; i++) {
462                 if (walk_state->operands[i]) {
463                         acpi_ut_remove_reference (walk_state->operands[i]);
464                         walk_state->operands[i] = NULL;
465                 }
466         }
467
468         return_ACPI_STATUS (AE_OK);
469 }
470
471
472 /*******************************************************************************
473  *
474  * FUNCTION:    acpi_ds_obj_stack_push
475  *
476  * PARAMETERS:  Object              - Object to push
477  *              walk_state          - Current Walk state
478  *
479  * RETURN:      Status
480  *
481  * DESCRIPTION: Push an object onto this walk's object/operand stack
482  *
483  ******************************************************************************/
484
485 acpi_status
486 acpi_ds_obj_stack_push (
487         void                            *object,
488         struct acpi_walk_state          *walk_state)
489 {
490         ACPI_FUNCTION_NAME ("ds_obj_stack_push");
491
492
493         /* Check for stack overflow */
494
495         if (walk_state->num_operands >= ACPI_OBJ_NUM_OPERANDS) {
496                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
497                         "overflow! Obj=%p State=%p #Ops=%X\n",
498                         object, walk_state, walk_state->num_operands));
499                 return (AE_STACK_OVERFLOW);
500         }
501
502         /* Put the object onto the stack */
503
504         walk_state->operands [walk_state->num_operands] = object;
505         walk_state->num_operands++;
506
507         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Obj=%p [%s] State=%p #Ops=%X\n",
508                           object, acpi_ut_get_object_type_name ((union acpi_operand_object *) object),
509                           walk_state, walk_state->num_operands));
510
511         return (AE_OK);
512 }
513
514
515 #if 0
516 /*******************************************************************************
517  *
518  * FUNCTION:    acpi_ds_obj_stack_pop_object
519  *
520  * PARAMETERS:  pop_count           - Number of objects/entries to pop
521  *              walk_state          - Current Walk state
522  *
523  * RETURN:      Status
524  *
525  * DESCRIPTION: Pop this walk's object stack.  Objects on the stack are NOT
526  *              deleted by this routine.
527  *
528  ******************************************************************************/
529
530 acpi_status
531 acpi_ds_obj_stack_pop_object (
532         union acpi_operand_object       **object,
533         struct acpi_walk_state          *walk_state)
534 {
535         ACPI_FUNCTION_NAME ("ds_obj_stack_pop_object");
536
537
538         /* Check for stack underflow */
539
540         if (walk_state->num_operands == 0) {
541                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
542                         "Missing operand/stack empty! State=%p #Ops=%X\n",
543                         walk_state, walk_state->num_operands));
544                 *object = NULL;
545                 return (AE_AML_NO_OPERAND);
546         }
547
548         /* Pop the stack */
549
550         walk_state->num_operands--;
551
552         /* Check for a valid operand */
553
554         if (!walk_state->operands [walk_state->num_operands]) {
555                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
556                         "Null operand! State=%p #Ops=%X\n",
557                         walk_state, walk_state->num_operands));
558                 *object = NULL;
559                 return (AE_AML_NO_OPERAND);
560         }
561
562         /* Get operand and set stack entry to null */
563
564         *object = walk_state->operands [walk_state->num_operands];
565         walk_state->operands [walk_state->num_operands] = NULL;
566
567         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Obj=%p [%s] State=%p #Ops=%X\n",
568                           *object, acpi_ut_get_object_type_name (*object),
569                           walk_state, walk_state->num_operands));
570
571         return (AE_OK);
572 }
573 #endif
574
575
576 /*******************************************************************************
577  *
578  * FUNCTION:    acpi_ds_obj_stack_pop
579  *
580  * PARAMETERS:  pop_count           - Number of objects/entries to pop
581  *              walk_state          - Current Walk state
582  *
583  * RETURN:      Status
584  *
585  * DESCRIPTION: Pop this walk's object stack.  Objects on the stack are NOT
586  *              deleted by this routine.
587  *
588  ******************************************************************************/
589
590 acpi_status
591 acpi_ds_obj_stack_pop (
592         u32                             pop_count,
593         struct acpi_walk_state          *walk_state)
594 {
595         u32                             i;
596
597         ACPI_FUNCTION_NAME ("ds_obj_stack_pop");
598
599
600         for (i = 0; i < pop_count; i++) {
601                 /* Check for stack underflow */
602
603                 if (walk_state->num_operands == 0) {
604                         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
605                                 "Underflow! Count=%X State=%p #Ops=%X\n",
606                                 pop_count, walk_state, walk_state->num_operands));
607                         return (AE_STACK_UNDERFLOW);
608                 }
609
610                 /* Just set the stack entry to null */
611
612                 walk_state->num_operands--;
613                 walk_state->operands [walk_state->num_operands] = NULL;
614         }
615
616         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%X\n",
617                           pop_count, walk_state, walk_state->num_operands));
618
619         return (AE_OK);
620 }
621
622
623 /*******************************************************************************
624  *
625  * FUNCTION:    acpi_ds_obj_stack_pop_and_delete
626  *
627  * PARAMETERS:  pop_count           - Number of objects/entries to pop
628  *              walk_state          - Current Walk state
629  *
630  * RETURN:      Status
631  *
632  * DESCRIPTION: Pop this walk's object stack and delete each object that is
633  *              popped off.
634  *
635  ******************************************************************************/
636
637 acpi_status
638 acpi_ds_obj_stack_pop_and_delete (
639         u32                             pop_count,
640         struct acpi_walk_state          *walk_state)
641 {
642         u32                             i;
643         union acpi_operand_object       *obj_desc;
644
645
646         ACPI_FUNCTION_NAME ("ds_obj_stack_pop_and_delete");
647
648
649         for (i = 0; i < pop_count; i++) {
650                 /* Check for stack underflow */
651
652                 if (walk_state->num_operands == 0) {
653                         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
654                                 "Underflow! Count=%X State=%p #Ops=%X\n",
655                                 pop_count, walk_state, walk_state->num_operands));
656                         return (AE_STACK_UNDERFLOW);
657                 }
658
659                 /* Pop the stack and delete an object if present in this stack entry */
660
661                 walk_state->num_operands--;
662                 obj_desc = walk_state->operands [walk_state->num_operands];
663                 if (obj_desc) {
664                         acpi_ut_remove_reference (walk_state->operands [walk_state->num_operands]);
665                         walk_state->operands [walk_state->num_operands] = NULL;
666                 }
667         }
668
669         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%X\n",
670                           pop_count, walk_state, walk_state->num_operands));
671
672         return (AE_OK);
673 }
674
675
676 /*******************************************************************************
677  *
678  * FUNCTION:    acpi_ds_obj_stack_get_value
679  *
680  * PARAMETERS:  Index               - Stack index whose value is desired.  Based
681  *                                    on the top of the stack (index=0 == top)
682  *              walk_state          - Current Walk state
683  *
684  * RETURN:      Status
685  *
686  * DESCRIPTION: Retrieve an object from this walk's object stack.  Index must
687  *              be within the range of the current stack pointer.
688  *
689  ******************************************************************************/
690
691 void *
692 acpi_ds_obj_stack_get_value (
693         u32                             index,
694         struct acpi_walk_state          *walk_state)
695 {
696
697         ACPI_FUNCTION_TRACE_PTR ("ds_obj_stack_get_value", walk_state);
698
699
700         /* Can't do it if the stack is empty */
701
702         if (walk_state->num_operands == 0) {
703                 return_PTR (NULL);
704         }
705
706         /* or if the index is past the top of the stack */
707
708         if (index > (walk_state->num_operands - (u32) 1)) {
709                 return_PTR (NULL);
710         }
711
712         return_PTR (walk_state->operands[(acpi_native_uint)(walk_state->num_operands - 1) -
713                           index]);
714 }
715
716
717 /*******************************************************************************
718  *
719  * FUNCTION:    acpi_ds_get_current_walk_state
720  *
721  * PARAMETERS:  Thread          - Get current active state for this Thread
722  *
723  * RETURN:      Pointer to the current walk state
724  *
725  * DESCRIPTION: Get the walk state that is at the head of the list (the "current"
726  *              walk state.)
727  *
728  ******************************************************************************/
729
730 struct acpi_walk_state *
731 acpi_ds_get_current_walk_state (
732         struct acpi_thread_state        *thread)
733
734 {
735         ACPI_FUNCTION_NAME ("ds_get_current_walk_state");
736
737
738         if (!thread) {
739                 return (NULL);
740         }
741
742         ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "Current walk_state %p\n",
743                 thread->walk_state_list));
744
745         return (thread->walk_state_list);
746 }
747
748
749 /*******************************************************************************
750  *
751  * FUNCTION:    acpi_ds_push_walk_state
752  *
753  * PARAMETERS:  walk_state      - State to push
754  *              walk_list       - The list that owns the walk stack
755  *
756  * RETURN:      None
757  *
758  * DESCRIPTION: Place the walk_state at the head of the state list.
759  *
760  ******************************************************************************/
761
762 void
763 acpi_ds_push_walk_state (
764         struct acpi_walk_state          *walk_state,
765         struct acpi_thread_state        *thread)
766 {
767         ACPI_FUNCTION_TRACE ("ds_push_walk_state");
768
769
770         walk_state->next      = thread->walk_state_list;
771         thread->walk_state_list = walk_state;
772
773         return_VOID;
774 }
775
776
777 /*******************************************************************************
778  *
779  * FUNCTION:    acpi_ds_pop_walk_state
780  *
781  * PARAMETERS:  walk_list       - The list that owns the walk stack
782  *
783  * RETURN:      A walk_state object popped from the stack
784  *
785  * DESCRIPTION: Remove and return the walkstate object that is at the head of
786  *              the walk stack for the given walk list.  NULL indicates that
787  *              the list is empty.
788  *
789  ******************************************************************************/
790
791 struct acpi_walk_state *
792 acpi_ds_pop_walk_state (
793         struct acpi_thread_state        *thread)
794 {
795         struct acpi_walk_state          *walk_state;
796
797
798         ACPI_FUNCTION_TRACE ("ds_pop_walk_state");
799
800
801         walk_state = thread->walk_state_list;
802
803         if (walk_state) {
804                 /* Next walk state becomes the current walk state */
805
806                 thread->walk_state_list = walk_state->next;
807
808                 /*
809                  * Don't clear the NEXT field, this serves as an indicator
810                  * that there is a parent WALK STATE
811                  *     NO: walk_state->Next = NULL;
812                  */
813         }
814
815         return_PTR (walk_state);
816 }
817
818
819 /*******************************************************************************
820  *
821  * FUNCTION:    acpi_ds_create_walk_state
822  *
823  * PARAMETERS:  Origin          - Starting point for this walk
824  *              Thread          - Current thread state
825  *
826  * RETURN:      Pointer to the new walk state.
827  *
828  * DESCRIPTION: Allocate and initialize a new walk state.  The current walk
829  *              state is set to this new state.
830  *
831  ******************************************************************************/
832
833 struct acpi_walk_state *
834 acpi_ds_create_walk_state (
835         acpi_owner_id                   owner_id,
836         union acpi_parse_object         *origin,
837         union acpi_operand_object       *mth_desc,
838         struct acpi_thread_state        *thread)
839 {
840         struct acpi_walk_state          *walk_state;
841         acpi_status                     status;
842
843
844         ACPI_FUNCTION_TRACE ("ds_create_walk_state");
845
846
847         walk_state = acpi_ut_acquire_from_cache (ACPI_MEM_LIST_WALK);
848         if (!walk_state) {
849                 return_PTR (NULL);
850         }
851
852         walk_state->data_type       = ACPI_DESC_TYPE_WALK;
853         walk_state->owner_id        = owner_id;
854         walk_state->origin          = origin;
855         walk_state->method_desc     = mth_desc;
856         walk_state->thread          = thread;
857
858         walk_state->parser_state.start_op = origin;
859
860         /* Init the method args/local */
861
862 #if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))
863         acpi_ds_method_data_init (walk_state);
864 #endif
865
866         /* Create an initial result stack entry */
867
868         status = acpi_ds_result_stack_push (walk_state);
869         if (ACPI_FAILURE (status)) {
870                 return_PTR (NULL);
871         }
872
873         /* Put the new state at the head of the walk list */
874
875         if (thread) {
876                 acpi_ds_push_walk_state (walk_state, thread);
877         }
878
879         return_PTR (walk_state);
880 }
881
882
883 /*******************************************************************************
884  *
885  * FUNCTION:    acpi_ds_init_aml_walk
886  *
887  * PARAMETERS:  walk_state      - New state to be initialized
888  *              Op              - Current parse op
889  *              method_node     - Control method NS node, if any
890  *              aml_start       - Start of AML
891  *              aml_length      - Length of AML
892  *              Params          - Method args, if any
893  *              return_obj_desc - Where to store a return object, if any
894  *              pass_number     - 1, 2, or 3
895  *
896  * RETURN:      Status
897  *
898  * DESCRIPTION: Initialize a walk state for a pass 1 or 2 parse tree walk
899  *
900  ******************************************************************************/
901
902 acpi_status
903 acpi_ds_init_aml_walk (
904         struct acpi_walk_state          *walk_state,
905         union acpi_parse_object         *op,
906         struct acpi_namespace_node      *method_node,
907         u8                              *aml_start,
908         u32                             aml_length,
909         union acpi_operand_object       **params,
910         union acpi_operand_object       **return_obj_desc,
911         u32                             pass_number)
912 {
913         acpi_status                     status;
914         struct acpi_parse_state         *parser_state = &walk_state->parser_state;
915         union acpi_parse_object         *extra_op;
916
917
918         ACPI_FUNCTION_TRACE ("ds_init_aml_walk");
919
920
921         walk_state->parser_state.aml    =
922         walk_state->parser_state.aml_start = aml_start;
923         walk_state->parser_state.aml_end =
924         walk_state->parser_state.pkg_end = aml_start + aml_length;
925
926         /* The next_op of the next_walk will be the beginning of the method */
927
928         walk_state->next_op             = NULL;
929         walk_state->params              = params;
930         walk_state->caller_return_desc  = return_obj_desc;
931
932         status = acpi_ps_init_scope (&walk_state->parser_state, op);
933         if (ACPI_FAILURE (status)) {
934                 return_ACPI_STATUS (status);
935         }
936
937         if (method_node) {
938                 walk_state->parser_state.start_node = method_node;
939                 walk_state->walk_type            = ACPI_WALK_METHOD;
940                 walk_state->method_node          = method_node;
941                 walk_state->method_desc          = acpi_ns_get_attached_object (method_node);
942
943                 /* Push start scope on scope stack and make it current  */
944
945                 status = acpi_ds_scope_stack_push (method_node, ACPI_TYPE_METHOD, walk_state);
946                 if (ACPI_FAILURE (status)) {
947                         return_ACPI_STATUS (status);
948                 }
949
950                 /* Init the method arguments */
951
952                 status = acpi_ds_method_data_init_args (params, ACPI_METHOD_NUM_ARGS, walk_state);
953                 if (ACPI_FAILURE (status)) {
954                         return_ACPI_STATUS (status);
955                 }
956         }
957         else {
958                 /*
959                  * Setup the current scope.
960                  * Find a Named Op that has a namespace node associated with it.
961                  * search upwards from this Op.  Current scope is the first
962                  * Op with a namespace node.
963                  */
964                 extra_op = parser_state->start_op;
965                 while (extra_op && !extra_op->common.node) {
966                         extra_op = extra_op->common.parent;
967                 }
968
969                 if (!extra_op) {
970                         parser_state->start_node = NULL;
971                 }
972                 else {
973                         parser_state->start_node = extra_op->common.node;
974                 }
975
976                 if (parser_state->start_node) {
977                         /* Push start scope on scope stack and make it current  */
978
979                         status = acpi_ds_scope_stack_push (parser_state->start_node,
980                                           parser_state->start_node->type, walk_state);
981                         if (ACPI_FAILURE (status)) {
982                                 return_ACPI_STATUS (status);
983                         }
984                 }
985         }
986
987         status = acpi_ds_init_callbacks (walk_state, pass_number);
988         return_ACPI_STATUS (status);
989 }
990
991
992 /*******************************************************************************
993  *
994  * FUNCTION:    acpi_ds_delete_walk_state
995  *
996  * PARAMETERS:  walk_state      - State to delete
997  *
998  * RETURN:      Status
999  *
1000  * DESCRIPTION: Delete a walk state including all internal data structures
1001  *
1002  ******************************************************************************/
1003
1004 void
1005 acpi_ds_delete_walk_state (
1006         struct acpi_walk_state          *walk_state)
1007 {
1008         union acpi_generic_state        *state;
1009
1010
1011         ACPI_FUNCTION_TRACE_PTR ("ds_delete_walk_state", walk_state);
1012
1013
1014         if (!walk_state) {
1015                 return;
1016         }
1017
1018         if (walk_state->data_type != ACPI_DESC_TYPE_WALK) {
1019                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "%p is not a valid walk state\n", walk_state));
1020                 return;
1021         }
1022
1023         if (walk_state->parser_state.scope) {
1024                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "%p walk still has a scope list\n", walk_state));
1025         }
1026
1027         /* Always must free any linked control states */
1028
1029         while (walk_state->control_state) {
1030                 state = walk_state->control_state;
1031                 walk_state->control_state = state->common.next;
1032
1033                 acpi_ut_delete_generic_state (state);
1034         }
1035
1036         /* Always must free any linked parse states */
1037
1038         while (walk_state->scope_info) {
1039                 state = walk_state->scope_info;
1040                 walk_state->scope_info = state->common.next;
1041
1042                 acpi_ut_delete_generic_state (state);
1043         }
1044
1045         /* Always must free any stacked result states */
1046
1047         while (walk_state->results) {
1048                 state = walk_state->results;
1049                 walk_state->results = state->common.next;
1050
1051                 acpi_ut_delete_generic_state (state);
1052         }
1053
1054         acpi_ut_release_to_cache (ACPI_MEM_LIST_WALK, walk_state);
1055         return_VOID;
1056 }
1057
1058
1059 /******************************************************************************
1060  *
1061  * FUNCTION:    acpi_ds_delete_walk_state_cache
1062  *
1063  * PARAMETERS:  None
1064  *
1065  * RETURN:      Status
1066  *
1067  * DESCRIPTION: Purge the global state object cache.  Used during subsystem
1068  *              termination.
1069  *
1070  ******************************************************************************/
1071
1072 void
1073 acpi_ds_delete_walk_state_cache (
1074         void)
1075 {
1076         ACPI_FUNCTION_TRACE ("ds_delete_walk_state_cache");
1077
1078
1079         acpi_ut_delete_generic_cache (ACPI_MEM_LIST_WALK);
1080         return_VOID;
1081 }
1082
1083