Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
[pandora-kernel.git] / drivers / acpi / acpica / exresop.c
1
2 /******************************************************************************
3  *
4  * Module Name: exresop - AML Interpreter operand/object resolution
5  *
6  *****************************************************************************/
7
8 /*
9  * Copyright (C) 2000 - 2011, Intel Corp.
10  * All rights reserved.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions, and the following disclaimer,
17  *    without modification.
18  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
19  *    substantially similar to the "NO WARRANTY" disclaimer below
20  *    ("Disclaimer") and any redistribution must be conditioned upon
21  *    including a substantially similar Disclaimer requirement for further
22  *    binary redistribution.
23  * 3. Neither the names of the above-listed copyright holders nor the names
24  *    of any contributors may be used to endorse or promote products derived
25  *    from this software without specific prior written permission.
26  *
27  * Alternatively, this software may be distributed under the terms of the
28  * GNU General Public License ("GPL") version 2 as published by the Free
29  * Software Foundation.
30  *
31  * NO WARRANTY
32  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
33  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
34  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
35  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
36  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
40  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
41  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
42  * POSSIBILITY OF SUCH DAMAGES.
43  */
44
45 #include <acpi/acpi.h>
46 #include "accommon.h"
47 #include "amlcode.h"
48 #include "acparser.h"
49 #include "acinterp.h"
50 #include "acnamesp.h"
51
52 #define _COMPONENT          ACPI_EXECUTER
53 ACPI_MODULE_NAME("exresop")
54
55 /* Local prototypes */
56 static acpi_status
57 acpi_ex_check_object_type(acpi_object_type type_needed,
58                           acpi_object_type this_type, void *object);
59
60 /*******************************************************************************
61  *
62  * FUNCTION:    acpi_ex_check_object_type
63  *
64  * PARAMETERS:  type_needed         Object type needed
65  *              this_type           Actual object type
66  *              Object              Object pointer
67  *
68  * RETURN:      Status
69  *
70  * DESCRIPTION: Check required type against actual type
71  *
72  ******************************************************************************/
73
74 static acpi_status
75 acpi_ex_check_object_type(acpi_object_type type_needed,
76                           acpi_object_type this_type, void *object)
77 {
78         ACPI_FUNCTION_ENTRY();
79
80         if (type_needed == ACPI_TYPE_ANY) {
81
82                 /* All types OK, so we don't perform any typechecks */
83
84                 return (AE_OK);
85         }
86
87         if (type_needed == ACPI_TYPE_LOCAL_REFERENCE) {
88                 /*
89                  * Allow the AML "Constant" opcodes (Zero, One, etc.) to be reference
90                  * objects and thus allow them to be targets.  (As per the ACPI
91                  * specification, a store to a constant is a noop.)
92                  */
93                 if ((this_type == ACPI_TYPE_INTEGER) &&
94                     (((union acpi_operand_object *)object)->common.
95                      flags & AOPOBJ_AML_CONSTANT)) {
96                         return (AE_OK);
97                 }
98         }
99
100         if (type_needed != this_type) {
101                 ACPI_ERROR((AE_INFO,
102                             "Needed type [%s], found [%s] %p",
103                             acpi_ut_get_type_name(type_needed),
104                             acpi_ut_get_type_name(this_type), object));
105
106                 return (AE_AML_OPERAND_TYPE);
107         }
108
109         return (AE_OK);
110 }
111
112 /*******************************************************************************
113  *
114  * FUNCTION:    acpi_ex_resolve_operands
115  *
116  * PARAMETERS:  Opcode              - Opcode being interpreted
117  *              stack_ptr           - Pointer to the operand stack to be
118  *                                    resolved
119  *              walk_state          - Current state
120  *
121  * RETURN:      Status
122  *
123  * DESCRIPTION: Convert multiple input operands to the types required by the
124  *              target operator.
125  *
126  *      Each 5-bit group in arg_types represents one required
127  *      operand and indicates the required Type. The corresponding operand
128  *      will be converted to the required type if possible, otherwise we
129  *      abort with an exception.
130  *
131  ******************************************************************************/
132
133 acpi_status
134 acpi_ex_resolve_operands(u16 opcode,
135                          union acpi_operand_object ** stack_ptr,
136                          struct acpi_walk_state * walk_state)
137 {
138         union acpi_operand_object *obj_desc;
139         acpi_status status = AE_OK;
140         u8 object_type;
141         u32 arg_types;
142         const struct acpi_opcode_info *op_info;
143         u32 this_arg_type;
144         acpi_object_type type_needed;
145         u16 target_op = 0;
146
147         ACPI_FUNCTION_TRACE_U32(ex_resolve_operands, opcode);
148
149         op_info = acpi_ps_get_opcode_info(opcode);
150         if (op_info->class == AML_CLASS_UNKNOWN) {
151                 return_ACPI_STATUS(AE_AML_BAD_OPCODE);
152         }
153
154         arg_types = op_info->runtime_args;
155         if (arg_types == ARGI_INVALID_OPCODE) {
156                 ACPI_ERROR((AE_INFO, "Unknown AML opcode 0x%X", opcode));
157
158                 return_ACPI_STATUS(AE_AML_INTERNAL);
159         }
160
161         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
162                           "Opcode %X [%s] RequiredOperandTypes=%8.8X\n",
163                           opcode, op_info->name, arg_types));
164
165         /*
166          * Normal exit is with (arg_types == 0) at end of argument list.
167          * Function will return an exception from within the loop upon
168          * finding an entry which is not (or cannot be converted
169          * to) the required type; if stack underflows; or upon
170          * finding a NULL stack entry (which should not happen).
171          */
172         while (GET_CURRENT_ARG_TYPE(arg_types)) {
173                 if (!stack_ptr || !*stack_ptr) {
174                         ACPI_ERROR((AE_INFO, "Null stack entry at %p",
175                                     stack_ptr));
176
177                         return_ACPI_STATUS(AE_AML_INTERNAL);
178                 }
179
180                 /* Extract useful items */
181
182                 obj_desc = *stack_ptr;
183
184                 /* Decode the descriptor type */
185
186                 switch (ACPI_GET_DESCRIPTOR_TYPE(obj_desc)) {
187                 case ACPI_DESC_TYPE_NAMED:
188
189                         /* Namespace Node */
190
191                         object_type =
192                             ((struct acpi_namespace_node *)obj_desc)->type;
193
194                         /*
195                          * Resolve an alias object. The construction of these objects
196                          * guarantees that there is only one level of alias indirection;
197                          * thus, the attached object is always the aliased namespace node
198                          */
199                         if (object_type == ACPI_TYPE_LOCAL_ALIAS) {
200                                 obj_desc =
201                                     acpi_ns_get_attached_object((struct
202                                                                  acpi_namespace_node
203                                                                  *)obj_desc);
204                                 *stack_ptr = obj_desc;
205                                 object_type =
206                                     ((struct acpi_namespace_node *)obj_desc)->
207                                     type;
208                         }
209                         break;
210
211                 case ACPI_DESC_TYPE_OPERAND:
212
213                         /* ACPI internal object */
214
215                         object_type = obj_desc->common.type;
216
217                         /* Check for bad acpi_object_type */
218
219                         if (!acpi_ut_valid_object_type(object_type)) {
220                                 ACPI_ERROR((AE_INFO,
221                                             "Bad operand object type [0x%X]",
222                                             object_type));
223
224                                 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
225                         }
226
227                         if (object_type == (u8) ACPI_TYPE_LOCAL_REFERENCE) {
228
229                                 /* Validate the Reference */
230
231                                 switch (obj_desc->reference.class) {
232                                 case ACPI_REFCLASS_DEBUG:
233
234                                         target_op = AML_DEBUG_OP;
235
236                                         /*lint -fallthrough */
237
238                                 case ACPI_REFCLASS_ARG:
239                                 case ACPI_REFCLASS_LOCAL:
240                                 case ACPI_REFCLASS_INDEX:
241                                 case ACPI_REFCLASS_REFOF:
242                                 case ACPI_REFCLASS_TABLE:       /* ddb_handle from LOAD_OP or LOAD_TABLE_OP */
243                                 case ACPI_REFCLASS_NAME:        /* Reference to a named object */
244
245                                         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
246                                                           "Operand is a Reference, Class [%s] %2.2X\n",
247                                                           acpi_ut_get_reference_name
248                                                           (obj_desc),
249                                                           obj_desc->reference.
250                                                           class));
251                                         break;
252
253                                 default:
254
255                                         ACPI_ERROR((AE_INFO,
256                                                     "Unknown Reference Class 0x%2.2X in %p",
257                                                     obj_desc->reference.class,
258                                                     obj_desc));
259
260                                         return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
261                                 }
262                         }
263                         break;
264
265                 default:
266
267                         /* Invalid descriptor */
268
269                         ACPI_ERROR((AE_INFO, "Invalid descriptor %p [%s]",
270                                     obj_desc,
271                                     acpi_ut_get_descriptor_name(obj_desc)));
272
273                         return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
274                 }
275
276                 /* Get one argument type, point to the next */
277
278                 this_arg_type = GET_CURRENT_ARG_TYPE(arg_types);
279                 INCREMENT_ARG_LIST(arg_types);
280
281                 /*
282                  * Handle cases where the object does not need to be
283                  * resolved to a value
284                  */
285                 switch (this_arg_type) {
286                 case ARGI_REF_OR_STRING:        /* Can be a String or Reference */
287
288                         if ((ACPI_GET_DESCRIPTOR_TYPE(obj_desc) ==
289                              ACPI_DESC_TYPE_OPERAND)
290                             && (obj_desc->common.type == ACPI_TYPE_STRING)) {
291                                 /*
292                                  * String found - the string references a named object and
293                                  * must be resolved to a node
294                                  */
295                                 goto next_operand;
296                         }
297
298                         /*
299                          * Else not a string - fall through to the normal Reference
300                          * case below
301                          */
302                         /*lint -fallthrough */
303
304                 case ARGI_REFERENCE:    /* References: */
305                 case ARGI_INTEGER_REF:
306                 case ARGI_OBJECT_REF:
307                 case ARGI_DEVICE_REF:
308                 case ARGI_TARGETREF:    /* Allows implicit conversion rules before store */
309                 case ARGI_FIXED_TARGET: /* No implicit conversion before store to target */
310                 case ARGI_SIMPLE_TARGET:        /* Name, Local, or Arg - no implicit conversion  */
311
312                         /*
313                          * Need an operand of type ACPI_TYPE_LOCAL_REFERENCE
314                          * A Namespace Node is OK as-is
315                          */
316                         if (ACPI_GET_DESCRIPTOR_TYPE(obj_desc) ==
317                             ACPI_DESC_TYPE_NAMED) {
318                                 goto next_operand;
319                         }
320
321                         status =
322                             acpi_ex_check_object_type(ACPI_TYPE_LOCAL_REFERENCE,
323                                                       object_type, obj_desc);
324                         if (ACPI_FAILURE(status)) {
325                                 return_ACPI_STATUS(status);
326                         }
327                         goto next_operand;
328
329                 case ARGI_DATAREFOBJ:   /* Store operator only */
330
331                         /*
332                          * We don't want to resolve index_op reference objects during
333                          * a store because this would be an implicit de_ref_of operation.
334                          * Instead, we just want to store the reference object.
335                          * -- All others must be resolved below.
336                          */
337                         if ((opcode == AML_STORE_OP) &&
338                             ((*stack_ptr)->common.type ==
339                              ACPI_TYPE_LOCAL_REFERENCE)
340                             && ((*stack_ptr)->reference.class == ACPI_REFCLASS_INDEX)) {
341                                 goto next_operand;
342                         }
343                         break;
344
345                 default:
346                         /* All cases covered above */
347                         break;
348                 }
349
350                 /*
351                  * Resolve this object to a value
352                  */
353                 status = acpi_ex_resolve_to_value(stack_ptr, walk_state);
354                 if (ACPI_FAILURE(status)) {
355                         return_ACPI_STATUS(status);
356                 }
357
358                 /* Get the resolved object */
359
360                 obj_desc = *stack_ptr;
361
362                 /*
363                  * Check the resulting object (value) type
364                  */
365                 switch (this_arg_type) {
366                         /*
367                          * For the simple cases, only one type of resolved object
368                          * is allowed
369                          */
370                 case ARGI_MUTEX:
371
372                         /* Need an operand of type ACPI_TYPE_MUTEX */
373
374                         type_needed = ACPI_TYPE_MUTEX;
375                         break;
376
377                 case ARGI_EVENT:
378
379                         /* Need an operand of type ACPI_TYPE_EVENT */
380
381                         type_needed = ACPI_TYPE_EVENT;
382                         break;
383
384                 case ARGI_PACKAGE:      /* Package */
385
386                         /* Need an operand of type ACPI_TYPE_PACKAGE */
387
388                         type_needed = ACPI_TYPE_PACKAGE;
389                         break;
390
391                 case ARGI_ANYTYPE:
392
393                         /* Any operand type will do */
394
395                         type_needed = ACPI_TYPE_ANY;
396                         break;
397
398                 case ARGI_DDBHANDLE:
399
400                         /* Need an operand of type ACPI_TYPE_DDB_HANDLE */
401
402                         type_needed = ACPI_TYPE_LOCAL_REFERENCE;
403                         break;
404
405                         /*
406                          * The more complex cases allow multiple resolved object types
407                          */
408                 case ARGI_INTEGER:
409
410                         /*
411                          * Need an operand of type ACPI_TYPE_INTEGER,
412                          * But we can implicitly convert from a STRING or BUFFER
413                          * Aka - "Implicit Source Operand Conversion"
414                          */
415                         status =
416                             acpi_ex_convert_to_integer(obj_desc, stack_ptr, 16);
417                         if (ACPI_FAILURE(status)) {
418                                 if (status == AE_TYPE) {
419                                         ACPI_ERROR((AE_INFO,
420                                                     "Needed [Integer/String/Buffer], found [%s] %p",
421                                                     acpi_ut_get_object_type_name
422                                                     (obj_desc), obj_desc));
423
424                                         return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
425                                 }
426
427                                 return_ACPI_STATUS(status);
428                         }
429
430                         if (obj_desc != *stack_ptr) {
431                                 acpi_ut_remove_reference(obj_desc);
432                         }
433                         goto next_operand;
434
435                 case ARGI_BUFFER:
436
437                         /*
438                          * Need an operand of type ACPI_TYPE_BUFFER,
439                          * But we can implicitly convert from a STRING or INTEGER
440                          * Aka - "Implicit Source Operand Conversion"
441                          */
442                         status = acpi_ex_convert_to_buffer(obj_desc, stack_ptr);
443                         if (ACPI_FAILURE(status)) {
444                                 if (status == AE_TYPE) {
445                                         ACPI_ERROR((AE_INFO,
446                                                     "Needed [Integer/String/Buffer], found [%s] %p",
447                                                     acpi_ut_get_object_type_name
448                                                     (obj_desc), obj_desc));
449
450                                         return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
451                                 }
452
453                                 return_ACPI_STATUS(status);
454                         }
455
456                         if (obj_desc != *stack_ptr) {
457                                 acpi_ut_remove_reference(obj_desc);
458                         }
459                         goto next_operand;
460
461                 case ARGI_STRING:
462
463                         /*
464                          * Need an operand of type ACPI_TYPE_STRING,
465                          * But we can implicitly convert from a BUFFER or INTEGER
466                          * Aka - "Implicit Source Operand Conversion"
467                          */
468                         status = acpi_ex_convert_to_string(obj_desc, stack_ptr,
469                                                            ACPI_IMPLICIT_CONVERT_HEX);
470                         if (ACPI_FAILURE(status)) {
471                                 if (status == AE_TYPE) {
472                                         ACPI_ERROR((AE_INFO,
473                                                     "Needed [Integer/String/Buffer], found [%s] %p",
474                                                     acpi_ut_get_object_type_name
475                                                     (obj_desc), obj_desc));
476
477                                         return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
478                                 }
479
480                                 return_ACPI_STATUS(status);
481                         }
482
483                         if (obj_desc != *stack_ptr) {
484                                 acpi_ut_remove_reference(obj_desc);
485                         }
486                         goto next_operand;
487
488                 case ARGI_COMPUTEDATA:
489
490                         /* Need an operand of type INTEGER, STRING or BUFFER */
491
492                         switch (obj_desc->common.type) {
493                         case ACPI_TYPE_INTEGER:
494                         case ACPI_TYPE_STRING:
495                         case ACPI_TYPE_BUFFER:
496
497                                 /* Valid operand */
498                                 break;
499
500                         default:
501                                 ACPI_ERROR((AE_INFO,
502                                             "Needed [Integer/String/Buffer], found [%s] %p",
503                                             acpi_ut_get_object_type_name
504                                             (obj_desc), obj_desc));
505
506                                 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
507                         }
508                         goto next_operand;
509
510                 case ARGI_BUFFER_OR_STRING:
511
512                         /* Need an operand of type STRING or BUFFER */
513
514                         switch (obj_desc->common.type) {
515                         case ACPI_TYPE_STRING:
516                         case ACPI_TYPE_BUFFER:
517
518                                 /* Valid operand */
519                                 break;
520
521                         case ACPI_TYPE_INTEGER:
522
523                                 /* Highest priority conversion is to type Buffer */
524
525                                 status =
526                                     acpi_ex_convert_to_buffer(obj_desc,
527                                                               stack_ptr);
528                                 if (ACPI_FAILURE(status)) {
529                                         return_ACPI_STATUS(status);
530                                 }
531
532                                 if (obj_desc != *stack_ptr) {
533                                         acpi_ut_remove_reference(obj_desc);
534                                 }
535                                 break;
536
537                         default:
538                                 ACPI_ERROR((AE_INFO,
539                                             "Needed [Integer/String/Buffer], found [%s] %p",
540                                             acpi_ut_get_object_type_name
541                                             (obj_desc), obj_desc));
542
543                                 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
544                         }
545                         goto next_operand;
546
547                 case ARGI_DATAOBJECT:
548                         /*
549                          * ARGI_DATAOBJECT is only used by the size_of operator.
550                          * Need a buffer, string, package, or ref_of reference.
551                          *
552                          * The only reference allowed here is a direct reference to
553                          * a namespace node.
554                          */
555                         switch (obj_desc->common.type) {
556                         case ACPI_TYPE_PACKAGE:
557                         case ACPI_TYPE_STRING:
558                         case ACPI_TYPE_BUFFER:
559                         case ACPI_TYPE_LOCAL_REFERENCE:
560
561                                 /* Valid operand */
562                                 break;
563
564                         default:
565                                 ACPI_ERROR((AE_INFO,
566                                             "Needed [Buffer/String/Package/Reference], found [%s] %p",
567                                             acpi_ut_get_object_type_name
568                                             (obj_desc), obj_desc));
569
570                                 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
571                         }
572                         goto next_operand;
573
574                 case ARGI_COMPLEXOBJ:
575
576                         /* Need a buffer or package or (ACPI 2.0) String */
577
578                         switch (obj_desc->common.type) {
579                         case ACPI_TYPE_PACKAGE:
580                         case ACPI_TYPE_STRING:
581                         case ACPI_TYPE_BUFFER:
582
583                                 /* Valid operand */
584                                 break;
585
586                         default:
587                                 ACPI_ERROR((AE_INFO,
588                                             "Needed [Buffer/String/Package], found [%s] %p",
589                                             acpi_ut_get_object_type_name
590                                             (obj_desc), obj_desc));
591
592                                 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
593                         }
594                         goto next_operand;
595
596                 case ARGI_REGION_OR_BUFFER:     /* Used by Load() only */
597
598                         /* Need an operand of type REGION or a BUFFER (which could be a resolved region field) */
599
600                         switch (obj_desc->common.type) {
601                         case ACPI_TYPE_BUFFER:
602                         case ACPI_TYPE_REGION:
603
604                                 /* Valid operand */
605                                 break;
606
607                         default:
608                                 ACPI_ERROR((AE_INFO,
609                                             "Needed [Region/Buffer], found [%s] %p",
610                                             acpi_ut_get_object_type_name
611                                             (obj_desc), obj_desc));
612
613                                 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
614                         }
615                         goto next_operand;
616
617                 case ARGI_DATAREFOBJ:
618
619                         /* Used by the Store() operator only */
620
621                         switch (obj_desc->common.type) {
622                         case ACPI_TYPE_INTEGER:
623                         case ACPI_TYPE_PACKAGE:
624                         case ACPI_TYPE_STRING:
625                         case ACPI_TYPE_BUFFER:
626                         case ACPI_TYPE_BUFFER_FIELD:
627                         case ACPI_TYPE_LOCAL_REFERENCE:
628                         case ACPI_TYPE_LOCAL_REGION_FIELD:
629                         case ACPI_TYPE_LOCAL_BANK_FIELD:
630                         case ACPI_TYPE_LOCAL_INDEX_FIELD:
631                         case ACPI_TYPE_DDB_HANDLE:
632
633                                 /* Valid operand */
634                                 break;
635
636                         default:
637
638                                 if (acpi_gbl_enable_interpreter_slack) {
639                                         /*
640                                          * Enable original behavior of Store(), allowing any and all
641                                          * objects as the source operand.  The ACPI spec does not
642                                          * allow this, however.
643                                          */
644                                         break;
645                                 }
646
647                                 if (target_op == AML_DEBUG_OP) {
648
649                                         /* Allow store of any object to the Debug object */
650
651                                         break;
652                                 }
653
654                                 ACPI_ERROR((AE_INFO,
655                                             "Needed Integer/Buffer/String/Package/Ref/Ddb], found [%s] %p",
656                                             acpi_ut_get_object_type_name
657                                             (obj_desc), obj_desc));
658
659                                 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
660                         }
661                         goto next_operand;
662
663                 default:
664
665                         /* Unknown type */
666
667                         ACPI_ERROR((AE_INFO,
668                                     "Internal - Unknown ARGI (required operand) type 0x%X",
669                                     this_arg_type));
670
671                         return_ACPI_STATUS(AE_BAD_PARAMETER);
672                 }
673
674                 /*
675                  * Make sure that the original object was resolved to the
676                  * required object type (Simple cases only).
677                  */
678                 status = acpi_ex_check_object_type(type_needed,
679                                                    (*stack_ptr)->common.type,
680                                                    *stack_ptr);
681                 if (ACPI_FAILURE(status)) {
682                         return_ACPI_STATUS(status);
683                 }
684
685               next_operand:
686                 /*
687                  * If more operands needed, decrement stack_ptr to point
688                  * to next operand on stack
689                  */
690                 if (GET_CURRENT_ARG_TYPE(arg_types)) {
691                         stack_ptr--;
692                 }
693         }
694
695         ACPI_DUMP_OPERANDS(walk_state->operands,
696                            acpi_ps_get_opcode_name(opcode),
697                            walk_state->num_operands);
698
699         return_ACPI_STATUS(status);
700 }