Merge remote-tracking branch 'upstream' into next
[cascardo/linux.git] / drivers / acpi / acpica / dsfield.c
1 /******************************************************************************
2  *
3  * Module Name: dsfield - Dispatcher field routines
4  *
5  *****************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2012, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43
44 #include <acpi/acpi.h>
45 #include "accommon.h"
46 #include "amlcode.h"
47 #include "acdispat.h"
48 #include "acinterp.h"
49 #include "acnamesp.h"
50 #include "acparser.h"
51
52 #define _COMPONENT          ACPI_DISPATCHER
53 ACPI_MODULE_NAME("dsfield")
54
55 /* Local prototypes */
56 #ifdef ACPI_ASL_COMPILER
57 #include "acdisasm.h"
58 static acpi_status
59 acpi_ds_create_external_region(acpi_status lookup_status,
60                                union acpi_parse_object *op,
61                                char *path,
62                                struct acpi_walk_state *walk_state,
63                                struct acpi_namespace_node **node);
64 #endif
65
66 static acpi_status
67 acpi_ds_get_field_names(struct acpi_create_field_info *info,
68                         struct acpi_walk_state *walk_state,
69                         union acpi_parse_object *arg);
70
71 #ifdef ACPI_ASL_COMPILER
72 /*******************************************************************************
73  *
74  * FUNCTION:    acpi_ds_create_external_region (iASL Disassembler only)
75  *
76  * PARAMETERS:  lookup_status   - Status from ns_lookup operation
77  *              op              - Op containing the Field definition and args
78  *              path            - Pathname of the region
79  *  `           walk_state      - Current method state
80  *              node            - Where the new region node is returned
81  *
82  * RETURN:      Status
83  *
84  * DESCRIPTION: Add region to the external list if NOT_FOUND. Create a new
85  *              region node/object.
86  *
87  ******************************************************************************/
88
89 static acpi_status
90 acpi_ds_create_external_region(acpi_status lookup_status,
91                                union acpi_parse_object *op,
92                                char *path,
93                                struct acpi_walk_state *walk_state,
94                                struct acpi_namespace_node **node)
95 {
96         acpi_status status;
97         union acpi_operand_object *obj_desc;
98
99         if (lookup_status != AE_NOT_FOUND) {
100                 return (lookup_status);
101         }
102
103         /*
104          * Table disassembly:
105          * operation_region not found. Generate an External for it, and
106          * insert the name into the namespace.
107          */
108         acpi_dm_add_to_external_list(op, path, ACPI_TYPE_REGION, 0);
109         status = acpi_ns_lookup(walk_state->scope_info, path, ACPI_TYPE_REGION,
110                                 ACPI_IMODE_LOAD_PASS1, ACPI_NS_SEARCH_PARENT,
111                                 walk_state, node);
112         if (ACPI_FAILURE(status)) {
113                 return (status);
114         }
115
116         /* Must create and install a region object for the new node */
117
118         obj_desc = acpi_ut_create_internal_object(ACPI_TYPE_REGION);
119         if (!obj_desc) {
120                 return (AE_NO_MEMORY);
121         }
122
123         obj_desc->region.node = *node;
124         status = acpi_ns_attach_object(*node, obj_desc, ACPI_TYPE_REGION);
125         return (status);
126 }
127 #endif
128
129 /*******************************************************************************
130  *
131  * FUNCTION:    acpi_ds_create_buffer_field
132  *
133  * PARAMETERS:  op                  - Current parse op (create_XXField)
134  *              walk_state          - Current state
135  *
136  * RETURN:      Status
137  *
138  * DESCRIPTION: Execute the create_field operators:
139  *              create_bit_field_op,
140  *              create_byte_field_op,
141  *              create_word_field_op,
142  *              create_dword_field_op,
143  *              create_qword_field_op,
144  *              create_field_op     (all of which define a field in a buffer)
145  *
146  ******************************************************************************/
147
148 acpi_status
149 acpi_ds_create_buffer_field(union acpi_parse_object *op,
150                             struct acpi_walk_state *walk_state)
151 {
152         union acpi_parse_object *arg;
153         struct acpi_namespace_node *node;
154         acpi_status status;
155         union acpi_operand_object *obj_desc;
156         union acpi_operand_object *second_desc = NULL;
157         u32 flags;
158
159         ACPI_FUNCTION_TRACE(ds_create_buffer_field);
160
161         /*
162          * Get the name_string argument (name of the new buffer_field)
163          */
164         if (op->common.aml_opcode == AML_CREATE_FIELD_OP) {
165
166                 /* For create_field, name is the 4th argument */
167
168                 arg = acpi_ps_get_arg(op, 3);
169         } else {
170                 /* For all other create_XXXField operators, name is the 3rd argument */
171
172                 arg = acpi_ps_get_arg(op, 2);
173         }
174
175         if (!arg) {
176                 return_ACPI_STATUS(AE_AML_NO_OPERAND);
177         }
178
179         if (walk_state->deferred_node) {
180                 node = walk_state->deferred_node;
181                 status = AE_OK;
182         } else {
183                 /* Execute flag should always be set when this function is entered */
184
185                 if (!(walk_state->parse_flags & ACPI_PARSE_EXECUTE)) {
186                         return_ACPI_STATUS(AE_AML_INTERNAL);
187                 }
188
189                 /* Creating new namespace node, should not already exist */
190
191                 flags = ACPI_NS_NO_UPSEARCH | ACPI_NS_DONT_OPEN_SCOPE |
192                     ACPI_NS_ERROR_IF_FOUND;
193
194                 /*
195                  * Mark node temporary if we are executing a normal control
196                  * method. (Don't mark if this is a module-level code method)
197                  */
198                 if (walk_state->method_node &&
199                     !(walk_state->parse_flags & ACPI_PARSE_MODULE_LEVEL)) {
200                         flags |= ACPI_NS_TEMPORARY;
201                 }
202
203                 /* Enter the name_string into the namespace */
204
205                 status =
206                     acpi_ns_lookup(walk_state->scope_info,
207                                    arg->common.value.string, ACPI_TYPE_ANY,
208                                    ACPI_IMODE_LOAD_PASS1, flags, walk_state,
209                                    &node);
210                 if (ACPI_FAILURE(status)) {
211                         ACPI_ERROR_NAMESPACE(arg->common.value.string, status);
212                         return_ACPI_STATUS(status);
213                 }
214         }
215
216         /*
217          * We could put the returned object (Node) on the object stack for later,
218          * but for now, we will put it in the "op" object that the parser uses,
219          * so we can get it again at the end of this scope.
220          */
221         op->common.node = node;
222
223         /*
224          * If there is no object attached to the node, this node was just created
225          * and we need to create the field object. Otherwise, this was a lookup
226          * of an existing node and we don't want to create the field object again.
227          */
228         obj_desc = acpi_ns_get_attached_object(node);
229         if (obj_desc) {
230                 return_ACPI_STATUS(AE_OK);
231         }
232
233         /*
234          * The Field definition is not fully parsed at this time.
235          * (We must save the address of the AML for the buffer and index operands)
236          */
237
238         /* Create the buffer field object */
239
240         obj_desc = acpi_ut_create_internal_object(ACPI_TYPE_BUFFER_FIELD);
241         if (!obj_desc) {
242                 status = AE_NO_MEMORY;
243                 goto cleanup;
244         }
245
246         /*
247          * Remember location in AML stream of the field unit opcode and operands --
248          * since the buffer and index operands must be evaluated.
249          */
250         second_desc = obj_desc->common.next_object;
251         second_desc->extra.aml_start = op->named.data;
252         second_desc->extra.aml_length = op->named.length;
253         obj_desc->buffer_field.node = node;
254
255         /* Attach constructed field descriptors to parent node */
256
257         status = acpi_ns_attach_object(node, obj_desc, ACPI_TYPE_BUFFER_FIELD);
258         if (ACPI_FAILURE(status)) {
259                 goto cleanup;
260         }
261
262       cleanup:
263
264         /* Remove local reference to the object */
265
266         acpi_ut_remove_reference(obj_desc);
267         return_ACPI_STATUS(status);
268 }
269
270 /*******************************************************************************
271  *
272  * FUNCTION:    acpi_ds_get_field_names
273  *
274  * PARAMETERS:  info            - create_field info structure
275  *  `           walk_state      - Current method state
276  *              arg             - First parser arg for the field name list
277  *
278  * RETURN:      Status
279  *
280  * DESCRIPTION: Process all named fields in a field declaration.  Names are
281  *              entered into the namespace.
282  *
283  ******************************************************************************/
284
285 static acpi_status
286 acpi_ds_get_field_names(struct acpi_create_field_info *info,
287                         struct acpi_walk_state *walk_state,
288                         union acpi_parse_object *arg)
289 {
290         acpi_status status;
291         u64 position;
292         union acpi_parse_object *child;
293
294         ACPI_FUNCTION_TRACE_PTR(ds_get_field_names, info);
295
296         /* First field starts at bit zero */
297
298         info->field_bit_position = 0;
299
300         /* Process all elements in the field list (of parse nodes) */
301
302         while (arg) {
303                 /*
304                  * Four types of field elements are handled:
305                  * 1) name - Enters a new named field into the namespace
306                  * 2) offset - specifies a bit offset
307                  * 3) access_as - changes the access mode/attributes
308                  * 4) connection - Associate a resource template with the field
309                  */
310                 switch (arg->common.aml_opcode) {
311                 case AML_INT_RESERVEDFIELD_OP:
312
313                         position = (u64) info->field_bit_position
314                             + (u64) arg->common.value.size;
315
316                         if (position > ACPI_UINT32_MAX) {
317                                 ACPI_ERROR((AE_INFO,
318                                             "Bit offset within field too large (> 0xFFFFFFFF)"));
319                                 return_ACPI_STATUS(AE_SUPPORT);
320                         }
321
322                         info->field_bit_position = (u32) position;
323                         break;
324
325                 case AML_INT_ACCESSFIELD_OP:
326                 case AML_INT_EXTACCESSFIELD_OP:
327                         /*
328                          * Get new access_type, access_attribute, and access_length fields
329                          * -- to be used for all field units that follow, until the
330                          * end-of-field or another access_as keyword is encountered.
331                          * NOTE. These three bytes are encoded in the integer value
332                          * of the parseop for convenience.
333                          *
334                          * In field_flags, preserve the flag bits other than the
335                          * ACCESS_TYPE bits.
336                          */
337
338                         /* access_type (byte_acc, word_acc, etc.) */
339
340                         info->field_flags = (u8)
341                             ((info->
342                               field_flags & ~(AML_FIELD_ACCESS_TYPE_MASK)) |
343                              ((u8)((u32)(arg->common.value.integer & 0x07))));
344
345                         /* access_attribute (attrib_quick, attrib_byte, etc.) */
346
347                         info->attribute =
348                             (u8)((arg->common.value.integer >> 8) & 0xFF);
349
350                         /* access_length (for serial/buffer protocols) */
351
352                         info->access_length =
353                             (u8)((arg->common.value.integer >> 16) & 0xFF);
354                         break;
355
356                 case AML_INT_CONNECTION_OP:
357                         /*
358                          * Clear any previous connection. New connection is used for all
359                          * fields that follow, similar to access_as
360                          */
361                         info->resource_buffer = NULL;
362                         info->connection_node = NULL;
363
364                         /*
365                          * A Connection() is either an actual resource descriptor (buffer)
366                          * or a named reference to a resource template
367                          */
368                         child = arg->common.value.arg;
369                         if (child->common.aml_opcode == AML_INT_BYTELIST_OP) {
370                                 info->resource_buffer = child->named.data;
371                                 info->resource_length =
372                                     (u16)child->named.value.integer;
373                         } else {
374                                 /* Lookup the Connection() namepath, it should already exist */
375
376                                 status = acpi_ns_lookup(walk_state->scope_info,
377                                                         child->common.value.
378                                                         name, ACPI_TYPE_ANY,
379                                                         ACPI_IMODE_EXECUTE,
380                                                         ACPI_NS_DONT_OPEN_SCOPE,
381                                                         walk_state,
382                                                         &info->connection_node);
383                                 if (ACPI_FAILURE(status)) {
384                                         ACPI_ERROR_NAMESPACE(child->common.
385                                                              value.name,
386                                                              status);
387                                         return_ACPI_STATUS(status);
388                                 }
389                         }
390                         break;
391
392                 case AML_INT_NAMEDFIELD_OP:
393
394                         /* Lookup the name, it should already exist */
395
396                         status = acpi_ns_lookup(walk_state->scope_info,
397                                                 (char *)&arg->named.name,
398                                                 info->field_type,
399                                                 ACPI_IMODE_EXECUTE,
400                                                 ACPI_NS_DONT_OPEN_SCOPE,
401                                                 walk_state, &info->field_node);
402                         if (ACPI_FAILURE(status)) {
403                                 ACPI_ERROR_NAMESPACE((char *)&arg->named.name,
404                                                      status);
405                                 return_ACPI_STATUS(status);
406                         } else {
407                                 arg->common.node = info->field_node;
408                                 info->field_bit_length = arg->common.value.size;
409
410                                 /*
411                                  * If there is no object attached to the node, this node was
412                                  * just created and we need to create the field object.
413                                  * Otherwise, this was a lookup of an existing node and we
414                                  * don't want to create the field object again.
415                                  */
416                                 if (!acpi_ns_get_attached_object
417                                     (info->field_node)) {
418                                         status = acpi_ex_prep_field_value(info);
419                                         if (ACPI_FAILURE(status)) {
420                                                 return_ACPI_STATUS(status);
421                                         }
422                                 }
423                         }
424
425                         /* Keep track of bit position for the next field */
426
427                         position = (u64) info->field_bit_position
428                             + (u64) arg->common.value.size;
429
430                         if (position > ACPI_UINT32_MAX) {
431                                 ACPI_ERROR((AE_INFO,
432                                             "Field [%4.4s] bit offset too large (> 0xFFFFFFFF)",
433                                             ACPI_CAST_PTR(char,
434                                                           &info->field_node->
435                                                           name)));
436                                 return_ACPI_STATUS(AE_SUPPORT);
437                         }
438
439                         info->field_bit_position += info->field_bit_length;
440                         break;
441
442                 default:
443
444                         ACPI_ERROR((AE_INFO,
445                                     "Invalid opcode in field list: 0x%X",
446                                     arg->common.aml_opcode));
447                         return_ACPI_STATUS(AE_AML_BAD_OPCODE);
448                 }
449
450                 arg = arg->common.next;
451         }
452
453         return_ACPI_STATUS(AE_OK);
454 }
455
456 /*******************************************************************************
457  *
458  * FUNCTION:    acpi_ds_create_field
459  *
460  * PARAMETERS:  op              - Op containing the Field definition and args
461  *              region_node     - Object for the containing Operation Region
462  *  `           walk_state      - Current method state
463  *
464  * RETURN:      Status
465  *
466  * DESCRIPTION: Create a new field in the specified operation region
467  *
468  ******************************************************************************/
469
470 acpi_status
471 acpi_ds_create_field(union acpi_parse_object *op,
472                      struct acpi_namespace_node *region_node,
473                      struct acpi_walk_state *walk_state)
474 {
475         acpi_status status;
476         union acpi_parse_object *arg;
477         struct acpi_create_field_info info;
478
479         ACPI_FUNCTION_TRACE_PTR(ds_create_field, op);
480
481         /* First arg is the name of the parent op_region (must already exist) */
482
483         arg = op->common.value.arg;
484
485         if (!region_node) {
486                 status =
487                     acpi_ns_lookup(walk_state->scope_info,
488                                    arg->common.value.name, ACPI_TYPE_REGION,
489                                    ACPI_IMODE_EXECUTE, ACPI_NS_SEARCH_PARENT,
490                                    walk_state, &region_node);
491 #ifdef ACPI_ASL_COMPILER
492                 status = acpi_ds_create_external_region(status, arg,
493                                                         arg->common.value.name,
494                                                         walk_state,
495                                                         &region_node);
496 #endif
497                 if (ACPI_FAILURE(status)) {
498                         ACPI_ERROR_NAMESPACE(arg->common.value.name, status);
499                         return_ACPI_STATUS(status);
500                 }
501         }
502
503         ACPI_MEMSET(&info, 0, sizeof(struct acpi_create_field_info));
504
505         /* Second arg is the field flags */
506
507         arg = arg->common.next;
508         info.field_flags = (u8) arg->common.value.integer;
509         info.attribute = 0;
510
511         /* Each remaining arg is a Named Field */
512
513         info.field_type = ACPI_TYPE_LOCAL_REGION_FIELD;
514         info.region_node = region_node;
515
516         status = acpi_ds_get_field_names(&info, walk_state, arg->common.next);
517         return_ACPI_STATUS(status);
518 }
519
520 /*******************************************************************************
521  *
522  * FUNCTION:    acpi_ds_init_field_objects
523  *
524  * PARAMETERS:  op              - Op containing the Field definition and args
525  *  `           walk_state      - Current method state
526  *
527  * RETURN:      Status
528  *
529  * DESCRIPTION: For each "Field Unit" name in the argument list that is
530  *              part of the field declaration, enter the name into the
531  *              namespace.
532  *
533  ******************************************************************************/
534
535 acpi_status
536 acpi_ds_init_field_objects(union acpi_parse_object *op,
537                            struct acpi_walk_state *walk_state)
538 {
539         acpi_status status;
540         union acpi_parse_object *arg = NULL;
541         struct acpi_namespace_node *node;
542         u8 type = 0;
543         u32 flags;
544
545         ACPI_FUNCTION_TRACE_PTR(ds_init_field_objects, op);
546
547         /* Execute flag should always be set when this function is entered */
548
549         if (!(walk_state->parse_flags & ACPI_PARSE_EXECUTE)) {
550                 if (walk_state->parse_flags & ACPI_PARSE_DEFERRED_OP) {
551
552                         /* bank_field Op is deferred, just return OK */
553
554                         return_ACPI_STATUS(AE_OK);
555                 }
556
557                 return_ACPI_STATUS(AE_AML_INTERNAL);
558         }
559
560         /*
561          * Get the field_list argument for this opcode. This is the start of the
562          * list of field elements.
563          */
564         switch (walk_state->opcode) {
565         case AML_FIELD_OP:
566                 arg = acpi_ps_get_arg(op, 2);
567                 type = ACPI_TYPE_LOCAL_REGION_FIELD;
568                 break;
569
570         case AML_BANK_FIELD_OP:
571                 arg = acpi_ps_get_arg(op, 4);
572                 type = ACPI_TYPE_LOCAL_BANK_FIELD;
573                 break;
574
575         case AML_INDEX_FIELD_OP:
576                 arg = acpi_ps_get_arg(op, 3);
577                 type = ACPI_TYPE_LOCAL_INDEX_FIELD;
578                 break;
579
580         default:
581                 return_ACPI_STATUS(AE_BAD_PARAMETER);
582         }
583
584         /* Creating new namespace node(s), should not already exist */
585
586         flags = ACPI_NS_NO_UPSEARCH | ACPI_NS_DONT_OPEN_SCOPE |
587             ACPI_NS_ERROR_IF_FOUND;
588
589         /*
590          * Mark node(s) temporary if we are executing a normal control
591          * method. (Don't mark if this is a module-level code method)
592          */
593         if (walk_state->method_node &&
594             !(walk_state->parse_flags & ACPI_PARSE_MODULE_LEVEL)) {
595                 flags |= ACPI_NS_TEMPORARY;
596         }
597
598         /*
599          * Walk the list of entries in the field_list
600          * Note: field_list can be of zero length. In this case, Arg will be NULL.
601          */
602         while (arg) {
603                 /*
604                  * Ignore OFFSET/ACCESSAS/CONNECTION terms here; we are only interested
605                  * in the field names in order to enter them into the namespace.
606                  */
607                 if (arg->common.aml_opcode == AML_INT_NAMEDFIELD_OP) {
608                         status = acpi_ns_lookup(walk_state->scope_info,
609                                                 (char *)&arg->named.name, type,
610                                                 ACPI_IMODE_LOAD_PASS1, flags,
611                                                 walk_state, &node);
612                         if (ACPI_FAILURE(status)) {
613                                 ACPI_ERROR_NAMESPACE((char *)&arg->named.name,
614                                                      status);
615                                 if (status != AE_ALREADY_EXISTS) {
616                                         return_ACPI_STATUS(status);
617                                 }
618
619                                 /* Name already exists, just ignore this error */
620
621                                 status = AE_OK;
622                         }
623
624                         arg->common.node = node;
625                 }
626
627                 /* Get the next field element in the list */
628
629                 arg = arg->common.next;
630         }
631
632         return_ACPI_STATUS(AE_OK);
633 }
634
635 /*******************************************************************************
636  *
637  * FUNCTION:    acpi_ds_create_bank_field
638  *
639  * PARAMETERS:  op              - Op containing the Field definition and args
640  *              region_node     - Object for the containing Operation Region
641  *              walk_state      - Current method state
642  *
643  * RETURN:      Status
644  *
645  * DESCRIPTION: Create a new bank field in the specified operation region
646  *
647  ******************************************************************************/
648
649 acpi_status
650 acpi_ds_create_bank_field(union acpi_parse_object *op,
651                           struct acpi_namespace_node *region_node,
652                           struct acpi_walk_state *walk_state)
653 {
654         acpi_status status;
655         union acpi_parse_object *arg;
656         struct acpi_create_field_info info;
657
658         ACPI_FUNCTION_TRACE_PTR(ds_create_bank_field, op);
659
660         /* First arg is the name of the parent op_region (must already exist) */
661
662         arg = op->common.value.arg;
663         if (!region_node) {
664                 status =
665                     acpi_ns_lookup(walk_state->scope_info,
666                                    arg->common.value.name, ACPI_TYPE_REGION,
667                                    ACPI_IMODE_EXECUTE, ACPI_NS_SEARCH_PARENT,
668                                    walk_state, &region_node);
669 #ifdef ACPI_ASL_COMPILER
670                 status = acpi_ds_create_external_region(status, arg,
671                                                         arg->common.value.name,
672                                                         walk_state,
673                                                         &region_node);
674 #endif
675                 if (ACPI_FAILURE(status)) {
676                         ACPI_ERROR_NAMESPACE(arg->common.value.name, status);
677                         return_ACPI_STATUS(status);
678                 }
679         }
680
681         /* Second arg is the Bank Register (Field) (must already exist) */
682
683         arg = arg->common.next;
684         status =
685             acpi_ns_lookup(walk_state->scope_info, arg->common.value.string,
686                            ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
687                            ACPI_NS_SEARCH_PARENT, walk_state,
688                            &info.register_node);
689         if (ACPI_FAILURE(status)) {
690                 ACPI_ERROR_NAMESPACE(arg->common.value.string, status);
691                 return_ACPI_STATUS(status);
692         }
693
694         /*
695          * Third arg is the bank_value
696          * This arg is a term_arg, not a constant
697          * It will be evaluated later, by acpi_ds_eval_bank_field_operands
698          */
699         arg = arg->common.next;
700
701         /* Fourth arg is the field flags */
702
703         arg = arg->common.next;
704         info.field_flags = (u8) arg->common.value.integer;
705
706         /* Each remaining arg is a Named Field */
707
708         info.field_type = ACPI_TYPE_LOCAL_BANK_FIELD;
709         info.region_node = region_node;
710
711         /*
712          * Use Info.data_register_node to store bank_field Op
713          * It's safe because data_register_node will never be used when create bank field
714          * We store aml_start and aml_length in the bank_field Op for late evaluation
715          * Used in acpi_ex_prep_field_value(Info)
716          *
717          * TBD: Or, should we add a field in struct acpi_create_field_info, like "void *ParentOp"?
718          */
719         info.data_register_node = (struct acpi_namespace_node *)op;
720
721         status = acpi_ds_get_field_names(&info, walk_state, arg->common.next);
722         return_ACPI_STATUS(status);
723 }
724
725 /*******************************************************************************
726  *
727  * FUNCTION:    acpi_ds_create_index_field
728  *
729  * PARAMETERS:  op              - Op containing the Field definition and args
730  *              region_node     - Object for the containing Operation Region
731  *  `           walk_state      - Current method state
732  *
733  * RETURN:      Status
734  *
735  * DESCRIPTION: Create a new index field in the specified operation region
736  *
737  ******************************************************************************/
738
739 acpi_status
740 acpi_ds_create_index_field(union acpi_parse_object *op,
741                            struct acpi_namespace_node *region_node,
742                            struct acpi_walk_state *walk_state)
743 {
744         acpi_status status;
745         union acpi_parse_object *arg;
746         struct acpi_create_field_info info;
747
748         ACPI_FUNCTION_TRACE_PTR(ds_create_index_field, op);
749
750         /* First arg is the name of the Index register (must already exist) */
751
752         arg = op->common.value.arg;
753         status =
754             acpi_ns_lookup(walk_state->scope_info, arg->common.value.string,
755                            ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
756                            ACPI_NS_SEARCH_PARENT, walk_state,
757                            &info.register_node);
758         if (ACPI_FAILURE(status)) {
759                 ACPI_ERROR_NAMESPACE(arg->common.value.string, status);
760                 return_ACPI_STATUS(status);
761         }
762
763         /* Second arg is the data register (must already exist) */
764
765         arg = arg->common.next;
766         status =
767             acpi_ns_lookup(walk_state->scope_info, arg->common.value.string,
768                            ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
769                            ACPI_NS_SEARCH_PARENT, walk_state,
770                            &info.data_register_node);
771         if (ACPI_FAILURE(status)) {
772                 ACPI_ERROR_NAMESPACE(arg->common.value.string, status);
773                 return_ACPI_STATUS(status);
774         }
775
776         /* Next arg is the field flags */
777
778         arg = arg->common.next;
779         info.field_flags = (u8) arg->common.value.integer;
780
781         /* Each remaining arg is a Named Field */
782
783         info.field_type = ACPI_TYPE_LOCAL_INDEX_FIELD;
784         info.region_node = region_node;
785
786         status = acpi_ds_get_field_names(&info, walk_state, arg->common.next);
787         return_ACPI_STATUS(status);
788 }