Pull bugzilla-5737 into release branch
[linux-2.6] / drivers / acpi / parser / psscope.c
1 /******************************************************************************
2  *
3  * Module Name: psscope - Parser scope stack management routines
4  *
5  *****************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2006, 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 }