drivers/acpi/parser/psscope.c

   1 /******************************************************************************
   2  *
   3  * Module Name: psscope - Parser scope stack management routines
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2007, R. Byron Moore
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions, and the following disclaimer,
  16  *    without modification.
  17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  18  *    substantially similar to the "NO WARRANTY" disclaimer below
  19  *    ("Disclaimer") and any redistribution must be conditioned upon
  20  *    including a substantially similar Disclaimer requirement for further
  21  *    binary redistribution.
  22  * 3. Neither the names of the above-listed copyright holders nor the names
  23  *    of any contributors may be used to endorse or promote products derived
  24  *    from this software without specific prior written permission.
  25  *
  26  * Alternatively, this software may be distributed under the terms of the
  27  * GNU General Public License ("GPL") version 2 as published by the Free
  28  * Software Foundation.
  29  *
  30  * NO WARRANTY
  31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  41  * POSSIBILITY OF SUCH DAMAGES.
  42  */
  43
  44 #include <acpi/acpi.h>
  45 #include <acpi/acparser.h>
  46
  47 #define _COMPONENT          ACPI_PARSER
  48 ACPI_MODULE_NAME("psscope")
  49
  50 /*******************************************************************************
  51  *
  52  * FUNCTION:    acpi_ps_get_parent_scope
  53  *
  54  * PARAMETERS:  parser_state        - Current parser state object
  55  *
  56  * RETURN:      Pointer to an Op object
  57  *
  58  * DESCRIPTION: Get parent of current op being parsed
  59  *
  60  ******************************************************************************/
  61 union acpi_parse_object *acpi_ps_get_parent_scope(struct acpi_parse_state
  62                                                   *parser_state)
  63 {
  64
  65         return (parser_state->scope->parse_scope.op);
  66 }
  67
  68 /*******************************************************************************
  69  *
  70  * FUNCTION:    acpi_ps_has_completed_scope
  71  *
  72  * PARAMETERS:  parser_state        - Current parser state object
  73  *
  74  * RETURN:      Boolean, TRUE = scope completed.
  75  *
  76  * DESCRIPTION: Is parsing of current argument complete?  Determined by
  77  *              1) AML pointer is at or beyond the end of the scope
  78  *              2) The scope argument count has reached zero.
  79  *
  80  ******************************************************************************/
  81
  82 u8 acpi_ps_has_completed_scope(struct acpi_parse_state * parser_state)
  83 {
  84
  85         return ((u8)
  86                 ((parser_state->aml >= parser_state->scope->parse_scope.arg_end
  87                   || !parser_state->scope->parse_scope.arg_count)));
  88 }
  89
  90 /*******************************************************************************
  91  *
  92  * FUNCTION:    acpi_ps_init_scope
  93  *
  94  * PARAMETERS:  parser_state        - Current parser state object
  95  *              Root                - the Root Node of this new scope
  96  *
  97  * RETURN:      Status
  98  *
  99  * DESCRIPTION: Allocate and init a new scope object
 100  *
 101  ******************************************************************************/
 102
 103 acpi_status
 104 acpi_ps_init_scope(struct acpi_parse_state * parser_state,
 105                    union acpi_parse_object * root_op)
 106 {
 107         union acpi_generic_state *scope;
 108
 109         ACPI_FUNCTION_TRACE_PTR(ps_init_scope, root_op);
 110
 111         scope = acpi_ut_create_generic_state();
 112         if (!scope) {
 113                 return_ACPI_STATUS(AE_NO_MEMORY);
 114         }
 115
 116         scope->common.descriptor_type = ACPI_DESC_TYPE_STATE_RPSCOPE;
 117         scope->parse_scope.op = root_op;
 118         scope->parse_scope.arg_count = ACPI_VAR_ARGS;
 119         scope->parse_scope.arg_end = parser_state->aml_end;
 120         scope->parse_scope.pkg_end = parser_state->aml_end;
 121
 122         parser_state->scope = scope;
 123         parser_state->start_op = root_op;
 124
 125         return_ACPI_STATUS(AE_OK);
 126 }
 127
 128 /*******************************************************************************
 129  *
 130  * FUNCTION:    acpi_ps_push_scope
 131  *
 132  * PARAMETERS:  parser_state        - Current parser state object
 133  *              Op                  - Current op to be pushed
 134  *              remaining_args      - List of args remaining
 135  *              arg_count           - Fixed or variable number of args
 136  *
 137  * RETURN:      Status
 138  *
 139  * DESCRIPTION: Push current op to begin parsing its argument
 140  *
 141  ******************************************************************************/
 142
 143 acpi_status
 144 acpi_ps_push_scope(struct acpi_parse_state *parser_state,
 145                    union acpi_parse_object *op,
 146                    u32 remaining_args, u32 arg_count)
 147 {
 148         union acpi_generic_state *scope;
 149
 150         ACPI_FUNCTION_TRACE_PTR(ps_push_scope, op);
 151
 152         scope = acpi_ut_create_generic_state();
 153         if (!scope) {
 154                 return_ACPI_STATUS(AE_NO_MEMORY);
 155         }
 156
 157         scope->common.descriptor_type = ACPI_DESC_TYPE_STATE_PSCOPE;
 158         scope->parse_scope.op = op;
 159         scope->parse_scope.arg_list = remaining_args;
 160         scope->parse_scope.arg_count = arg_count;
 161         scope->parse_scope.pkg_end = parser_state->pkg_end;
 162
 163         /* Push onto scope stack */
 164
 165         acpi_ut_push_generic_state(&parser_state->scope, scope);
 166
 167         if (arg_count == ACPI_VAR_ARGS) {
 168
 169                 /* Multiple arguments */
 170
 171                 scope->parse_scope.arg_end = parser_state->pkg_end;
 172         } else {
 173                 /* Single argument */
 174
 175                 scope->parse_scope.arg_end = ACPI_TO_POINTER(ACPI_MAX_PTR);
 176         }
 177
 178         return_ACPI_STATUS(AE_OK);
 179 }
 180
 181 /*******************************************************************************
 182  *
 183  * FUNCTION:    acpi_ps_pop_scope
 184  *
 185  * PARAMETERS:  parser_state        - Current parser state object
 186  *              Op                  - Where the popped op is returned
 187  *              arg_list            - Where the popped "next argument" is
 188  *                                    returned
 189  *              arg_count           - Count of objects in arg_list
 190  *
 191  * RETURN:      Status
 192  *
 193  * DESCRIPTION: Return to parsing a previous op
 194  *
 195  ******************************************************************************/
 196
 197 void
 198 acpi_ps_pop_scope(struct acpi_parse_state *parser_state,
 199                   union acpi_parse_object **op, u32 * arg_list, u32 * arg_count)
 200 {
 201         union acpi_generic_state *scope = parser_state->scope;
 202
 203         ACPI_FUNCTION_TRACE(ps_pop_scope);
 204
 205         /* Only pop the scope if there is in fact a next scope */
 206
 207         if (scope->common.next) {
 208                 scope = acpi_ut_pop_generic_state(&parser_state->scope);
 209
 210                 /* Return to parsing previous op */
 211
 212                 *op = scope->parse_scope.op;
 213                 *arg_list = scope->parse_scope.arg_list;
 214                 *arg_count = scope->parse_scope.arg_count;
 215                 parser_state->pkg_end = scope->parse_scope.pkg_end;
 216
 217                 /* All done with this scope state structure */
 218
 219                 acpi_ut_delete_generic_state(scope);
 220         } else {
 221                 /* Empty parse stack, prepare to fetch next opcode */
 222
 223                 *op = NULL;
 224                 *arg_list = 0;
 225                 *arg_count = 0;
 226         }
 227
 228         ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
 229                           "Popped Op %p Args %X\n", *op, *arg_count));
 230         return_VOID;
 231 }
 232
 233 /*******************************************************************************
 234  *
 235  * FUNCTION:    acpi_ps_cleanup_scope
 236  *
 237  * PARAMETERS:  parser_state        - Current parser state object
 238  *
 239  * RETURN:      None
 240  *
 241  * DESCRIPTION: Destroy available list, remaining stack levels, and return
 242  *              root scope
 243  *
 244  ******************************************************************************/
 245
 246 void acpi_ps_cleanup_scope(struct acpi_parse_state *parser_state)
 247 {
 248         union acpi_generic_state *scope;
 249
 250         ACPI_FUNCTION_TRACE_PTR(ps_cleanup_scope, parser_state);
 251
 252         if (!parser_state) {
 253                 return_VOID;
 254         }
 255
 256         /* Delete anything on the scope stack */
 257
 258         while (parser_state->scope) {
 259                 scope = acpi_ut_pop_generic_state(&parser_state->scope);
 260                 acpi_ut_delete_generic_state(scope);
 261         }
 262
 263         return_VOID;
 264 }