drivers/acpi/acpica/psscope.c

   1 /******************************************************************************
   2  *
   3  * Module Name: psscope - Parser scope stack management 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 "acparser.h"
  47
  48 #define _COMPONENT          ACPI_PARSER
  49 ACPI_MODULE_NAME("psscope")
  50
  51 /*******************************************************************************
  52  *
  53  * FUNCTION:    acpi_ps_get_parent_scope
  54  *
  55  * PARAMETERS:  parser_state        - Current parser state object
  56  *
  57  * RETURN:      Pointer to an Op object
  58  *
  59  * DESCRIPTION: Get parent of current op being parsed
  60  *
  61  ******************************************************************************/
  62 union acpi_parse_object *acpi_ps_get_parent_scope(struct acpi_parse_state
  63                                                   *parser_state)
  64 {
  65
  66         return (parser_state->scope->parse_scope.op);
  67 }
  68
  69 /*******************************************************************************
  70  *
  71  * FUNCTION:    acpi_ps_has_completed_scope
  72  *
  73  * PARAMETERS:  parser_state        - Current parser state object
  74  *
  75  * RETURN:      Boolean, TRUE = scope completed.
  76  *
  77  * DESCRIPTION: Is parsing of current argument complete?  Determined by
  78  *              1) AML pointer is at or beyond the end of the scope
  79  *              2) The scope argument count has reached zero.
  80  *
  81  ******************************************************************************/
  82
  83 u8 acpi_ps_has_completed_scope(struct acpi_parse_state * parser_state)
  84 {
  85
  86         return ((u8)
  87                 ((parser_state->aml >= parser_state->scope->parse_scope.arg_end
  88                   || !parser_state->scope->parse_scope.arg_count)));
  89 }
  90
  91 /*******************************************************************************
  92  *
  93  * FUNCTION:    acpi_ps_init_scope
  94  *
  95  * PARAMETERS:  parser_state        - Current parser state object
  96  *              Root                - the Root Node of this new scope
  97  *
  98  * RETURN:      Status
  99  *
 100  * DESCRIPTION: Allocate and init a new scope object
 101  *
 102  ******************************************************************************/
 103
 104 acpi_status
 105 acpi_ps_init_scope(struct acpi_parse_state * parser_state,
 106                    union acpi_parse_object * root_op)
 107 {
 108         union acpi_generic_state *scope;
 109
 110         ACPI_FUNCTION_TRACE_PTR(ps_init_scope, root_op);
 111
 112         scope = acpi_ut_create_generic_state();
 113         if (!scope) {
 114                 return_ACPI_STATUS(AE_NO_MEMORY);
 115         }
 116
 117         scope->common.descriptor_type = ACPI_DESC_TYPE_STATE_RPSCOPE;
 118         scope->parse_scope.op = root_op;
 119         scope->parse_scope.arg_count = ACPI_VAR_ARGS;
 120         scope->parse_scope.arg_end = parser_state->aml_end;
 121         scope->parse_scope.pkg_end = parser_state->aml_end;
 122
 123         parser_state->scope = scope;
 124         parser_state->start_op = root_op;
 125
 126         return_ACPI_STATUS(AE_OK);
 127 }
 128
 129 /*******************************************************************************
 130  *
 131  * FUNCTION:    acpi_ps_push_scope
 132  *
 133  * PARAMETERS:  parser_state        - Current parser state object
 134  *              Op                  - Current op to be pushed
 135  *              remaining_args      - List of args remaining
 136  *              arg_count           - Fixed or variable number of args
 137  *
 138  * RETURN:      Status
 139  *
 140  * DESCRIPTION: Push current op to begin parsing its argument
 141  *
 142  ******************************************************************************/
 143
 144 acpi_status
 145 acpi_ps_push_scope(struct acpi_parse_state *parser_state,
 146                    union acpi_parse_object *op,
 147                    u32 remaining_args, u32 arg_count)
 148 {
 149         union acpi_generic_state *scope;
 150
 151         ACPI_FUNCTION_TRACE_PTR(ps_push_scope, op);
 152
 153         scope = acpi_ut_create_generic_state();
 154         if (!scope) {
 155                 return_ACPI_STATUS(AE_NO_MEMORY);
 156         }
 157
 158         scope->common.descriptor_type = ACPI_DESC_TYPE_STATE_PSCOPE;
 159         scope->parse_scope.op = op;
 160         scope->parse_scope.arg_list = remaining_args;
 161         scope->parse_scope.arg_count = arg_count;
 162         scope->parse_scope.pkg_end = parser_state->pkg_end;
 163
 164         /* Push onto scope stack */
 165
 166         acpi_ut_push_generic_state(&parser_state->scope, scope);
 167
 168         if (arg_count == ACPI_VAR_ARGS) {
 169
 170                 /* Multiple arguments */
 171
 172                 scope->parse_scope.arg_end = parser_state->pkg_end;
 173         } else {
 174                 /* Single argument */
 175
 176                 scope->parse_scope.arg_end = ACPI_TO_POINTER(ACPI_MAX_PTR);
 177         }
 178
 179         return_ACPI_STATUS(AE_OK);
 180 }
 181
 182 /*******************************************************************************
 183  *
 184  * FUNCTION:    acpi_ps_pop_scope
 185  *
 186  * PARAMETERS:  parser_state        - Current parser state object
 187  *              Op                  - Where the popped op is returned
 188  *              arg_list            - Where the popped "next argument" is
 189  *                                    returned
 190  *              arg_count           - Count of objects in arg_list
 191  *
 192  * RETURN:      Status
 193  *
 194  * DESCRIPTION: Return to parsing a previous op
 195  *
 196  ******************************************************************************/
 197
 198 void
 199 acpi_ps_pop_scope(struct acpi_parse_state *parser_state,
 200                   union acpi_parse_object **op, u32 * arg_list, u32 * arg_count)
 201 {
 202         union acpi_generic_state *scope = parser_state->scope;
 203
 204         ACPI_FUNCTION_TRACE(ps_pop_scope);
 205
 206         /* Only pop the scope if there is in fact a next scope */
 207
 208         if (scope->common.next) {
 209                 scope = acpi_ut_pop_generic_state(&parser_state->scope);
 210
 211                 /* Return to parsing previous op */
 212
 213                 *op = scope->parse_scope.op;
 214                 *arg_list = scope->parse_scope.arg_list;
 215                 *arg_count = scope->parse_scope.arg_count;
 216                 parser_state->pkg_end = scope->parse_scope.pkg_end;
 217
 218                 /* All done with this scope state structure */
 219
 220                 acpi_ut_delete_generic_state(scope);
 221         } else {
 222                 /* Empty parse stack, prepare to fetch next opcode */
 223
 224                 *op = NULL;
 225                 *arg_list = 0;
 226                 *arg_count = 0;
 227         }
 228
 229         ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
 230                           "Popped Op %p Args %X\n", *op, *arg_count));
 231         return_VOID;
 232 }
 233
 234 /*******************************************************************************
 235  *
 236  * FUNCTION:    acpi_ps_cleanup_scope
 237  *
 238  * PARAMETERS:  parser_state        - Current parser state object
 239  *
 240  * RETURN:      None
 241  *
 242  * DESCRIPTION: Destroy available list, remaining stack levels, and return
 243  *              root scope
 244  *
 245  ******************************************************************************/
 246
 247 void acpi_ps_cleanup_scope(struct acpi_parse_state *parser_state)
 248 {
 249         union acpi_generic_state *scope;
 250
 251         ACPI_FUNCTION_TRACE_PTR(ps_cleanup_scope, parser_state);
 252
 253         if (!parser_state) {
 254                 return_VOID;
 255         }
 256
 257         /* Delete anything on the scope stack */
 258
 259         while (parser_state->scope) {
 260                 scope = acpi_ut_pop_generic_state(&parser_state->scope);
 261                 acpi_ut_delete_generic_state(scope);
 262         }
 263
 264         return_VOID;
 265 }