drivers/acpi/acpica/dsfield.c

   1 /******************************************************************************
   2  *
   3  * Module Name: dsfield - Dispatcher field routines
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2008, 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 static acpi_status
  57 acpi_ds_get_field_names(struct acpi_create_field_info *info,
  58                         struct acpi_walk_state *walk_state,
  59                         union acpi_parse_object *arg);
  60
  61 /*******************************************************************************
  62  *
  63  * FUNCTION:    acpi_ds_create_buffer_field
  64  *
  65  * PARAMETERS:  Op                  - Current parse op (create_xXField)
  66  *              walk_state          - Current state
  67  *
  68  * RETURN:      Status
  69  *
  70  * DESCRIPTION: Execute the create_field operators:
  71  *              create_bit_field_op,
  72  *              create_byte_field_op,
  73  *              create_word_field_op,
  74  *              create_dword_field_op,
  75  *              create_qword_field_op,
  76  *              create_field_op     (all of which define a field in a buffer)
  77  *
  78  ******************************************************************************/
  79
  80 acpi_status
  81 acpi_ds_create_buffer_field(union acpi_parse_object *op,
  82                             struct acpi_walk_state *walk_state)
  83 {
  84         union acpi_parse_object *arg;
  85         struct acpi_namespace_node *node;
  86         acpi_status status;
  87         union acpi_operand_object *obj_desc;
  88         union acpi_operand_object *second_desc = NULL;
  89         u32 flags;
  90
  91         ACPI_FUNCTION_TRACE(ds_create_buffer_field);
  92
  93         /*
  94          * Get the name_string argument (name of the new buffer_field)
  95          */
  96         if (op->common.aml_opcode == AML_CREATE_FIELD_OP) {
  97
  98                 /* For create_field, name is the 4th argument */
  99
 100                 arg = acpi_ps_get_arg(op, 3);
 101         } else {
 102                 /* For all other create_xXXField operators, name is the 3rd argument */
 103
 104                 arg = acpi_ps_get_arg(op, 2);
 105         }
 106
 107         if (!arg) {
 108                 return_ACPI_STATUS(AE_AML_NO_OPERAND);
 109         }
 110
 111         if (walk_state->deferred_node) {
 112                 node = walk_state->deferred_node;
 113                 status = AE_OK;
 114         } else {
 115                 /* Execute flag should always be set when this function is entered */
 116
 117                 if (!(walk_state->parse_flags & ACPI_PARSE_EXECUTE)) {
 118                         return_ACPI_STATUS(AE_AML_INTERNAL);
 119                 }
 120
 121                 /* Creating new namespace node, should not already exist */
 122
 123                 flags = ACPI_NS_NO_UPSEARCH | ACPI_NS_DONT_OPEN_SCOPE |
 124                     ACPI_NS_ERROR_IF_FOUND;
 125
 126                 /*
 127                  * Mark node temporary if we are executing a normal control
 128                  * method. (Don't mark if this is a module-level code method)
 129                  */
 130                 if (walk_state->method_node &&
 131                     !(walk_state->parse_flags & ACPI_PARSE_MODULE_LEVEL)) {
 132                         flags |= ACPI_NS_TEMPORARY;
 133                 }
 134
 135                 /* Enter the name_string into the namespace */
 136
 137                 status =
 138                     acpi_ns_lookup(walk_state->scope_info,
 139                                    arg->common.value.string, ACPI_TYPE_ANY,
 140                                    ACPI_IMODE_LOAD_PASS1, flags, walk_state,
 141                                    &node);
 142                 if (ACPI_FAILURE(status)) {
 143                         ACPI_ERROR_NAMESPACE(arg->common.value.string, status);
 144                         return_ACPI_STATUS(status);
 145                 }
 146         }
 147
 148         /*
 149          * We could put the returned object (Node) on the object stack for later,
 150          * but for now, we will put it in the "op" object that the parser uses,
 151          * so we can get it again at the end of this scope.
 152          */
 153         op->common.node = node;
 154
 155         /*
 156          * If there is no object attached to the node, this node was just created
 157          * and we need to create the field object. Otherwise, this was a lookup
 158          * of an existing node and we don't want to create the field object again.
 159          */
 160         obj_desc = acpi_ns_get_attached_object(node);
 161         if (obj_desc) {
 162                 return_ACPI_STATUS(AE_OK);
 163         }
 164
 165         /*
 166          * The Field definition is not fully parsed at this time.
 167          * (We must save the address of the AML for the buffer and index operands)
 168          */
 169
 170         /* Create the buffer field object */
 171
 172         obj_desc = acpi_ut_create_internal_object(ACPI_TYPE_BUFFER_FIELD);
 173         if (!obj_desc) {
 174                 status = AE_NO_MEMORY;
 175                 goto cleanup;
 176         }
 177
 178         /*
 179          * Remember location in AML stream of the field unit opcode and operands --
 180          * since the buffer and index operands must be evaluated.
 181          */
 182         second_desc = obj_desc->common.next_object;
 183         second_desc->extra.aml_start = op->named.data;
 184         second_desc->extra.aml_length = op->named.length;
 185         obj_desc->buffer_field.node = node;
 186
 187         /* Attach constructed field descriptors to parent node */
 188
 189         status = acpi_ns_attach_object(node, obj_desc, ACPI_TYPE_BUFFER_FIELD);
 190         if (ACPI_FAILURE(status)) {
 191                 goto cleanup;
 192         }
 193
 194       cleanup:
 195
 196         /* Remove local reference to the object */
 197
 198         acpi_ut_remove_reference(obj_desc);
 199         return_ACPI_STATUS(status);
 200 }
 201
 202 /*******************************************************************************
 203  *
 204  * FUNCTION:    acpi_ds_get_field_names
 205  *
 206  * PARAMETERS:  Info            - create_field info structure
 207  *  `           walk_state      - Current method state
 208  *              Arg             - First parser arg for the field name list
 209  *
 210  * RETURN:      Status
 211  *
 212  * DESCRIPTION: Process all named fields in a field declaration.  Names are
 213  *              entered into the namespace.
 214  *
 215  ******************************************************************************/
 216
 217 static acpi_status
 218 acpi_ds_get_field_names(struct acpi_create_field_info *info,
 219                         struct acpi_walk_state *walk_state,
 220                         union acpi_parse_object *arg)
 221 {
 222         acpi_status status;
 223         acpi_integer position;
 224
 225         ACPI_FUNCTION_TRACE_PTR(ds_get_field_names, info);
 226
 227         /* First field starts at bit zero */
 228
 229         info->field_bit_position = 0;
 230
 231         /* Process all elements in the field list (of parse nodes) */
 232
 233         while (arg) {
 234                 /*
 235                  * Three types of field elements are handled:
 236                  * 1) Offset - specifies a bit offset
 237                  * 2) access_as - changes the access mode
 238                  * 3) Name - Enters a new named field into the namespace
 239                  */
 240                 switch (arg->common.aml_opcode) {
 241                 case AML_INT_RESERVEDFIELD_OP:
 242
 243                         position = (acpi_integer) info->field_bit_position
 244                             + (acpi_integer) arg->common.value.size;
 245
 246                         if (position > ACPI_UINT32_MAX) {
 247                                 ACPI_ERROR((AE_INFO,
 248                                             "Bit offset within field too large (> 0xFFFFFFFF)"));
 249                                 return_ACPI_STATUS(AE_SUPPORT);
 250                         }
 251
 252                         info->field_bit_position = (u32) position;
 253                         break;
 254
 255                 case AML_INT_ACCESSFIELD_OP:
 256
 257                         /*
 258                          * Get a new access_type and access_attribute -- to be used for all
 259                          * field units that follow, until field end or another access_as
 260                          * keyword.
 261                          *
 262                          * In field_flags, preserve the flag bits other than the
 263                          * ACCESS_TYPE bits
 264                          */
 265                         info->field_flags = (u8)
 266                             ((info->
 267                               field_flags & ~(AML_FIELD_ACCESS_TYPE_MASK)) |
 268                              ((u8) ((u32) arg->common.value.integer >> 8)));
 269
 270                         info->attribute = (u8) (arg->common.value.integer);
 271                         break;
 272
 273                 case AML_INT_NAMEDFIELD_OP:
 274
 275                         /* Lookup the name, it should already exist */
 276
 277                         status = acpi_ns_lookup(walk_state->scope_info,
 278                                                 (char *)&arg->named.name,
 279                                                 info->field_type,
 280                                                 ACPI_IMODE_EXECUTE,
 281                                                 ACPI_NS_DONT_OPEN_SCOPE,
 282                                                 walk_state, &info->field_node);
 283                         if (ACPI_FAILURE(status)) {
 284                                 ACPI_ERROR_NAMESPACE((char *)&arg->named.name,
 285                                                      status);
 286                                 return_ACPI_STATUS(status);
 287                         } else {
 288                                 arg->common.node = info->field_node;
 289                                 info->field_bit_length = arg->common.value.size;
 290
 291                                 /*
 292                                  * If there is no object attached to the node, this node was
 293                                  * just created and we need to create the field object.
 294                                  * Otherwise, this was a lookup of an existing node and we
 295                                  * don't want to create the field object again.
 296                                  */
 297                                 if (!acpi_ns_get_attached_object
 298                                     (info->field_node)) {
 299                                         status = acpi_ex_prep_field_value(info);
 300                                         if (ACPI_FAILURE(status)) {
 301                                                 return_ACPI_STATUS(status);
 302                                         }
 303                                 }
 304                         }
 305
 306                         /* Keep track of bit position for the next field */
 307
 308                         position = (acpi_integer) info->field_bit_position
 309                             + (acpi_integer) arg->common.value.size;
 310
 311                         if (position > ACPI_UINT32_MAX) {
 312                                 ACPI_ERROR((AE_INFO,
 313                                             "Field [%4.4s] bit offset too large (> 0xFFFFFFFF)",
 314                                             ACPI_CAST_PTR(char,
 315                                                           &info->field_node->
 316                                                           name)));
 317                                 return_ACPI_STATUS(AE_SUPPORT);
 318                         }
 319
 320                         info->field_bit_position += info->field_bit_length;
 321                         break;
 322
 323                 default:
 324
 325                         ACPI_ERROR((AE_INFO,
 326                                     "Invalid opcode in field list: %X",
 327                                     arg->common.aml_opcode));
 328                         return_ACPI_STATUS(AE_AML_BAD_OPCODE);
 329                 }
 330
 331                 arg = arg->common.next;
 332         }
 333
 334         return_ACPI_STATUS(AE_OK);
 335 }
 336
 337 /*******************************************************************************
 338  *
 339  * FUNCTION:    acpi_ds_create_field
 340  *
 341  * PARAMETERS:  Op              - Op containing the Field definition and args
 342  *              region_node     - Object for the containing Operation Region
 343  *  `           walk_state      - Current method state
 344  *
 345  * RETURN:      Status
 346  *
 347  * DESCRIPTION: Create a new field in the specified operation region
 348  *
 349  ******************************************************************************/
 350
 351 acpi_status
 352 acpi_ds_create_field(union acpi_parse_object *op,
 353                      struct acpi_namespace_node *region_node,
 354                      struct acpi_walk_state *walk_state)
 355 {
 356         acpi_status status;
 357         union acpi_parse_object *arg;
 358         struct acpi_create_field_info info;
 359
 360         ACPI_FUNCTION_TRACE_PTR(ds_create_field, op);
 361
 362         /* First arg is the name of the parent op_region (must already exist) */
 363
 364         arg = op->common.value.arg;
 365         if (!region_node) {
 366                 status =
 367                     acpi_ns_lookup(walk_state->scope_info,
 368                                    arg->common.value.name, ACPI_TYPE_REGION,
 369                                    ACPI_IMODE_EXECUTE, ACPI_NS_SEARCH_PARENT,
 370                                    walk_state, &region_node);
 371                 if (ACPI_FAILURE(status)) {
 372                         ACPI_ERROR_NAMESPACE(arg->common.value.name, status);
 373                         return_ACPI_STATUS(status);
 374                 }
 375         }
 376
 377         /* Second arg is the field flags */
 378
 379         arg = arg->common.next;
 380         info.field_flags = (u8) arg->common.value.integer;
 381         info.attribute = 0;
 382
 383         /* Each remaining arg is a Named Field */
 384
 385         info.field_type = ACPI_TYPE_LOCAL_REGION_FIELD;
 386         info.region_node = region_node;
 387
 388         status = acpi_ds_get_field_names(&info, walk_state, arg->common.next);
 389
 390         return_ACPI_STATUS(status);
 391 }
 392
 393 /*******************************************************************************
 394  *
 395  * FUNCTION:    acpi_ds_init_field_objects
 396  *
 397  * PARAMETERS:  Op              - Op containing the Field definition and args
 398  *  `           walk_state      - Current method state
 399  *
 400  * RETURN:      Status
 401  *
 402  * DESCRIPTION: For each "Field Unit" name in the argument list that is
 403  *              part of the field declaration, enter the name into the
 404  *              namespace.
 405  *
 406  ******************************************************************************/
 407
 408 acpi_status
 409 acpi_ds_init_field_objects(union acpi_parse_object *op,
 410                            struct acpi_walk_state *walk_state)
 411 {
 412         acpi_status status;
 413         union acpi_parse_object *arg = NULL;
 414         struct acpi_namespace_node *node;
 415         u8 type = 0;
 416         u32 flags;
 417
 418         ACPI_FUNCTION_TRACE_PTR(ds_init_field_objects, op);
 419
 420         /* Execute flag should always be set when this function is entered */
 421
 422         if (!(walk_state->parse_flags & ACPI_PARSE_EXECUTE)) {
 423                 if (walk_state->parse_flags & ACPI_PARSE_DEFERRED_OP) {
 424
 425                         /* bank_field Op is deferred, just return OK */
 426
 427                         return_ACPI_STATUS(AE_OK);
 428                 }
 429
 430                 return_ACPI_STATUS(AE_AML_INTERNAL);
 431         }
 432
 433         /*
 434          * Get the field_list argument for this opcode. This is the start of the
 435          * list of field elements.
 436          */
 437         switch (walk_state->opcode) {
 438         case AML_FIELD_OP:
 439                 arg = acpi_ps_get_arg(op, 2);
 440                 type = ACPI_TYPE_LOCAL_REGION_FIELD;
 441                 break;
 442
 443         case AML_BANK_FIELD_OP:
 444                 arg = acpi_ps_get_arg(op, 4);
 445                 type = ACPI_TYPE_LOCAL_BANK_FIELD;
 446                 break;
 447
 448         case AML_INDEX_FIELD_OP:
 449                 arg = acpi_ps_get_arg(op, 3);
 450                 type = ACPI_TYPE_LOCAL_INDEX_FIELD;
 451                 break;
 452
 453         default:
 454                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 455         }
 456
 457         /* Creating new namespace node(s), should not already exist */
 458
 459         flags = ACPI_NS_NO_UPSEARCH | ACPI_NS_DONT_OPEN_SCOPE |
 460             ACPI_NS_ERROR_IF_FOUND;
 461
 462         /*
 463          * Mark node(s) temporary if we are executing a normal control
 464          * method. (Don't mark if this is a module-level code method)
 465          */
 466         if (walk_state->method_node &&
 467             !(walk_state->parse_flags & ACPI_PARSE_MODULE_LEVEL)) {
 468                 flags |= ACPI_NS_TEMPORARY;
 469         }
 470
 471         /*
 472          * Walk the list of entries in the field_list
 473          * Note: field_list can be of zero length. In this case, Arg will be NULL.
 474          */
 475         while (arg) {
 476                 /*
 477                  * Ignore OFFSET and ACCESSAS terms here; we are only interested in the
 478                  * field names in order to enter them into the namespace.
 479                  */
 480                 if (arg->common.aml_opcode == AML_INT_NAMEDFIELD_OP) {
 481                         status = acpi_ns_lookup(walk_state->scope_info,
 482                                                 (char *)&arg->named.name, type,
 483                                                 ACPI_IMODE_LOAD_PASS1, flags,
 484                                                 walk_state, &node);
 485                         if (ACPI_FAILURE(status)) {
 486                                 ACPI_ERROR_NAMESPACE((char *)&arg->named.name,
 487                                                      status);
 488                                 if (status != AE_ALREADY_EXISTS) {
 489                                         return_ACPI_STATUS(status);
 490                                 }
 491
 492                                 /* Name already exists, just ignore this error */
 493
 494                                 status = AE_OK;
 495                         }
 496
 497                         arg->common.node = node;
 498                 }
 499
 500                 /* Get the next field element in the list */
 501
 502                 arg = arg->common.next;
 503         }
 504
 505         return_ACPI_STATUS(AE_OK);
 506 }
 507
 508 /*******************************************************************************
 509  *
 510  * FUNCTION:    acpi_ds_create_bank_field
 511  *
 512  * PARAMETERS:  Op              - Op containing the Field definition and args
 513  *              region_node     - Object for the containing Operation Region
 514  *              walk_state      - Current method state
 515  *
 516  * RETURN:      Status
 517  *
 518  * DESCRIPTION: Create a new bank field in the specified operation region
 519  *
 520  ******************************************************************************/
 521
 522 acpi_status
 523 acpi_ds_create_bank_field(union acpi_parse_object *op,
 524                           struct acpi_namespace_node *region_node,
 525                           struct acpi_walk_state *walk_state)
 526 {
 527         acpi_status status;
 528         union acpi_parse_object *arg;
 529         struct acpi_create_field_info info;
 530
 531         ACPI_FUNCTION_TRACE_PTR(ds_create_bank_field, op);
 532
 533         /* First arg is the name of the parent op_region (must already exist) */
 534
 535         arg = op->common.value.arg;
 536         if (!region_node) {
 537                 status =
 538                     acpi_ns_lookup(walk_state->scope_info,
 539                                    arg->common.value.name, ACPI_TYPE_REGION,
 540                                    ACPI_IMODE_EXECUTE, ACPI_NS_SEARCH_PARENT,
 541                                    walk_state, &region_node);
 542                 if (ACPI_FAILURE(status)) {
 543                         ACPI_ERROR_NAMESPACE(arg->common.value.name, status);
 544                         return_ACPI_STATUS(status);
 545                 }
 546         }
 547
 548         /* Second arg is the Bank Register (Field) (must already exist) */
 549
 550         arg = arg->common.next;
 551         status =
 552             acpi_ns_lookup(walk_state->scope_info, arg->common.value.string,
 553                            ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
 554                            ACPI_NS_SEARCH_PARENT, walk_state,
 555                            &info.register_node);
 556         if (ACPI_FAILURE(status)) {
 557                 ACPI_ERROR_NAMESPACE(arg->common.value.string, status);
 558                 return_ACPI_STATUS(status);
 559         }
 560
 561         /*
 562          * Third arg is the bank_value
 563          * This arg is a term_arg, not a constant
 564          * It will be evaluated later, by acpi_ds_eval_bank_field_operands
 565          */
 566         arg = arg->common.next;
 567
 568         /* Fourth arg is the field flags */
 569
 570         arg = arg->common.next;
 571         info.field_flags = (u8) arg->common.value.integer;
 572
 573         /* Each remaining arg is a Named Field */
 574
 575         info.field_type = ACPI_TYPE_LOCAL_BANK_FIELD;
 576         info.region_node = region_node;
 577
 578         /*
 579          * Use Info.data_register_node to store bank_field Op
 580          * It's safe because data_register_node will never be used when create bank field
 581          * We store aml_start and aml_length in the bank_field Op for late evaluation
 582          * Used in acpi_ex_prep_field_value(Info)
 583          *
 584          * TBD: Or, should we add a field in struct acpi_create_field_info, like "void *ParentOp"?
 585          */
 586         info.data_register_node = (struct acpi_namespace_node *)op;
 587
 588         status = acpi_ds_get_field_names(&info, walk_state, arg->common.next);
 589         return_ACPI_STATUS(status);
 590 }
 591
 592 /*******************************************************************************
 593  *
 594  * FUNCTION:    acpi_ds_create_index_field
 595  *
 596  * PARAMETERS:  Op              - Op containing the Field definition and args
 597  *              region_node     - Object for the containing Operation Region
 598  *  `           walk_state      - Current method state
 599  *
 600  * RETURN:      Status
 601  *
 602  * DESCRIPTION: Create a new index field in the specified operation region
 603  *
 604  ******************************************************************************/
 605
 606 acpi_status
 607 acpi_ds_create_index_field(union acpi_parse_object *op,
 608                            struct acpi_namespace_node *region_node,
 609                            struct acpi_walk_state *walk_state)
 610 {
 611         acpi_status status;
 612         union acpi_parse_object *arg;
 613         struct acpi_create_field_info info;
 614
 615         ACPI_FUNCTION_TRACE_PTR(ds_create_index_field, op);
 616
 617         /* First arg is the name of the Index register (must already exist) */
 618
 619         arg = op->common.value.arg;
 620         status =
 621             acpi_ns_lookup(walk_state->scope_info, arg->common.value.string,
 622                            ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
 623                            ACPI_NS_SEARCH_PARENT, walk_state,
 624                            &info.register_node);
 625         if (ACPI_FAILURE(status)) {
 626                 ACPI_ERROR_NAMESPACE(arg->common.value.string, status);
 627                 return_ACPI_STATUS(status);
 628         }
 629
 630         /* Second arg is the data register (must already exist) */
 631
 632         arg = arg->common.next;
 633         status =
 634             acpi_ns_lookup(walk_state->scope_info, arg->common.value.string,
 635                            ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
 636                            ACPI_NS_SEARCH_PARENT, walk_state,
 637                            &info.data_register_node);
 638         if (ACPI_FAILURE(status)) {
 639                 ACPI_ERROR_NAMESPACE(arg->common.value.string, status);
 640                 return_ACPI_STATUS(status);
 641         }
 642
 643         /* Next arg is the field flags */
 644
 645         arg = arg->common.next;
 646         info.field_flags = (u8) arg->common.value.integer;
 647
 648         /* Each remaining arg is a Named Field */
 649
 650         info.field_type = ACPI_TYPE_LOCAL_INDEX_FIELD;
 651         info.region_node = region_node;
 652
 653         status = acpi_ds_get_field_names(&info, walk_state, arg->common.next);
 654
 655         return_ACPI_STATUS(status);
 656 }