Linux-2.6.12-rc2
[linux-2.6/kvm.git] / drivers / acpi / parser / pstree.c
blob2140bd1ac10b382bdc707ff384aa225edccb4bd3
1 /******************************************************************************
3 * Module Name: pstree - Parser op tree manipulation/traversal/search
5 *****************************************************************************/
7 /*
8 * Copyright (C) 2000 - 2005, R. Byron Moore
9 * All rights reserved.
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.
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.
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.
45 #include <acpi/acpi.h>
46 #include <acpi/acparser.h>
47 #include <acpi/amlcode.h>
49 #define _COMPONENT ACPI_PARSER
50 ACPI_MODULE_NAME ("pstree")
53 /*******************************************************************************
55 * FUNCTION: acpi_ps_get_arg
57 * PARAMETERS: Op - Get an argument for this op
58 * Argn - Nth argument to get
60 * RETURN: The argument (as an Op object). NULL if argument does not exist
62 * DESCRIPTION: Get the specified op's argument.
64 ******************************************************************************/
66 union acpi_parse_object *
67 acpi_ps_get_arg (
68 union acpi_parse_object *op,
69 u32 argn)
71 union acpi_parse_object *arg = NULL;
72 const struct acpi_opcode_info *op_info;
75 ACPI_FUNCTION_ENTRY ();
78 /* Get the info structure for this opcode */
80 op_info = acpi_ps_get_opcode_info (op->common.aml_opcode);
81 if (op_info->class == AML_CLASS_UNKNOWN) {
82 /* Invalid opcode or ASCII character */
84 return (NULL);
87 /* Check if this opcode requires argument sub-objects */
89 if (!(op_info->flags & AML_HAS_ARGS)) {
90 /* Has no linked argument objects */
92 return (NULL);
95 /* Get the requested argument object */
97 arg = op->common.value.arg;
98 while (arg && argn) {
99 argn--;
100 arg = arg->common.next;
103 return (arg);
107 /*******************************************************************************
109 * FUNCTION: acpi_ps_append_arg
111 * PARAMETERS: Op - Append an argument to this Op.
112 * Arg - Argument Op to append
114 * RETURN: None.
116 * DESCRIPTION: Append an argument to an op's argument list (a NULL arg is OK)
118 ******************************************************************************/
120 void
121 acpi_ps_append_arg (
122 union acpi_parse_object *op,
123 union acpi_parse_object *arg)
125 union acpi_parse_object *prev_arg;
126 const struct acpi_opcode_info *op_info;
129 ACPI_FUNCTION_ENTRY ();
132 if (!op) {
133 return;
136 /* Get the info structure for this opcode */
138 op_info = acpi_ps_get_opcode_info (op->common.aml_opcode);
139 if (op_info->class == AML_CLASS_UNKNOWN) {
140 /* Invalid opcode */
142 ACPI_REPORT_ERROR (("ps_append_arg: Invalid AML Opcode: 0x%2.2X\n",
143 op->common.aml_opcode));
144 return;
147 /* Check if this opcode requires argument sub-objects */
149 if (!(op_info->flags & AML_HAS_ARGS)) {
150 /* Has no linked argument objects */
152 return;
156 /* Append the argument to the linked argument list */
158 if (op->common.value.arg) {
159 /* Append to existing argument list */
161 prev_arg = op->common.value.arg;
162 while (prev_arg->common.next) {
163 prev_arg = prev_arg->common.next;
165 prev_arg->common.next = arg;
168 else {
169 /* No argument list, this will be the first argument */
171 op->common.value.arg = arg;
175 /* Set the parent in this arg and any args linked after it */
177 while (arg) {
178 arg->common.parent = op;
179 arg = arg->common.next;
184 #ifdef ACPI_FUTURE_USAGE
186 /*******************************************************************************
188 * FUNCTION: acpi_ps_get_child
190 * PARAMETERS: Op - Get the child of this Op
192 * RETURN: Child Op, Null if none is found.
194 * DESCRIPTION: Get op's children or NULL if none
196 ******************************************************************************/
197 union acpi_parse_object *
198 acpi_ps_get_child (
199 union acpi_parse_object *op)
201 union acpi_parse_object *child = NULL;
204 ACPI_FUNCTION_ENTRY ();
207 switch (op->common.aml_opcode) {
208 case AML_SCOPE_OP:
209 case AML_ELSE_OP:
210 case AML_DEVICE_OP:
211 case AML_THERMAL_ZONE_OP:
212 case AML_INT_METHODCALL_OP:
214 child = acpi_ps_get_arg (op, 0);
215 break;
218 case AML_BUFFER_OP:
219 case AML_PACKAGE_OP:
220 case AML_METHOD_OP:
221 case AML_IF_OP:
222 case AML_WHILE_OP:
223 case AML_FIELD_OP:
225 child = acpi_ps_get_arg (op, 1);
226 break;
229 case AML_POWER_RES_OP:
230 case AML_INDEX_FIELD_OP:
232 child = acpi_ps_get_arg (op, 2);
233 break;
236 case AML_PROCESSOR_OP:
237 case AML_BANK_FIELD_OP:
239 child = acpi_ps_get_arg (op, 3);
240 break;
243 default:
244 /* All others have no children */
245 break;
248 return (child);
252 /*******************************************************************************
254 * FUNCTION: acpi_ps_get_depth_next
256 * PARAMETERS: Origin - Root of subtree to search
257 * Op - Last (previous) Op that was found
259 * RETURN: Next Op found in the search.
261 * DESCRIPTION: Get next op in tree (walking the tree in depth-first order)
262 * Return NULL when reaching "origin" or when walking up from root
264 ******************************************************************************/
266 union acpi_parse_object *
267 acpi_ps_get_depth_next (
268 union acpi_parse_object *origin,
269 union acpi_parse_object *op)
271 union acpi_parse_object *next = NULL;
272 union acpi_parse_object *parent;
273 union acpi_parse_object *arg;
276 ACPI_FUNCTION_ENTRY ();
279 if (!op) {
280 return (NULL);
283 /* look for an argument or child */
285 next = acpi_ps_get_arg (op, 0);
286 if (next) {
287 return (next);
290 /* look for a sibling */
292 next = op->common.next;
293 if (next) {
294 return (next);
297 /* look for a sibling of parent */
299 parent = op->common.parent;
301 while (parent) {
302 arg = acpi_ps_get_arg (parent, 0);
303 while (arg && (arg != origin) && (arg != op)) {
304 arg = arg->common.next;
307 if (arg == origin) {
308 /* reached parent of origin, end search */
310 return (NULL);
313 if (parent->common.next) {
314 /* found sibling of parent */
316 return (parent->common.next);
319 op = parent;
320 parent = parent->common.parent;
323 return (next);
326 #endif /* ACPI_FUTURE_USAGE */