drivers/acpi/parser/pstree.c

   1 /******************************************************************************
   2  *
   3  * Module Name: pstree - Parser op tree manipulation/traversal/search
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2004, 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
  45 #include <acpi/acpi.h>
  46 #include <acpi/acparser.h>
  47 #include <acpi/amlcode.h>
  48
  49 #define _COMPONENT          ACPI_PARSER
  50          ACPI_MODULE_NAME    ("pstree")
  51
  52
  53 /*******************************************************************************
  54  *
  55  * FUNCTION:    acpi_ps_get_arg
  56  *
  57  * PARAMETERS:  Op              - Get an argument for this op
  58  *              Argn            - Nth argument to get
  59  *
  60  * RETURN:      The argument (as an Op object).  NULL if argument does not exist
  61  *
  62  * DESCRIPTION: Get the specified op's argument.
  63  *
  64  ******************************************************************************/
  65
  66 union acpi_parse_object *
  67 acpi_ps_get_arg (
  68         union acpi_parse_object         *op,
  69         u32                             argn)
  70 {
  71         union acpi_parse_object         *arg = NULL;
  72         const struct acpi_opcode_info   *op_info;
  73
  74
  75         ACPI_FUNCTION_ENTRY ();
  76
  77
  78         /* Get the info structure for this opcode */
  79
  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 */
  83
  84                 return (NULL);
  85         }
  86
  87         /* Check if this opcode requires argument sub-objects */
  88
  89         if (!(op_info->flags & AML_HAS_ARGS)) {
  90                 /* Has no linked argument objects */
  91
  92                 return (NULL);
  93         }
  94
  95         /* Get the requested argument object */
  96
  97         arg = op->common.value.arg;
  98         while (arg && argn) {
  99                 argn--;
 100                 arg = arg->common.next;
 101         }
 102
 103         return (arg);
 104 }
 105
 106
 107 /*******************************************************************************
 108  *
 109  * FUNCTION:    acpi_ps_append_arg
 110  *
 111  * PARAMETERS:  Op              - Append an argument to this Op.
 112  *              Arg             - Argument Op to append
 113  *
 114  * RETURN:      None.
 115  *
 116  * DESCRIPTION: Append an argument to an op's argument list (a NULL arg is OK)
 117  *
 118  ******************************************************************************/
 119
 120 void
 121 acpi_ps_append_arg (
 122         union acpi_parse_object         *op,
 123         union acpi_parse_object         *arg)
 124 {
 125         union acpi_parse_object         *prev_arg;
 126         const struct acpi_opcode_info   *op_info;
 127
 128
 129         ACPI_FUNCTION_ENTRY ();
 130
 131
 132         if (!op) {
 133                 return;
 134         }
 135
 136         /* Get the info structure for this opcode */
 137
 138         op_info = acpi_ps_get_opcode_info (op->common.aml_opcode);
 139         if (op_info->class == AML_CLASS_UNKNOWN) {
 140                 /* Invalid opcode */
 141
 142                 ACPI_REPORT_ERROR (("ps_append_arg: Invalid AML Opcode: 0x%2.2X\n",
 143                         op->common.aml_opcode));
 144                 return;
 145         }
 146
 147         /* Check if this opcode requires argument sub-objects */
 148
 149         if (!(op_info->flags & AML_HAS_ARGS)) {
 150                 /* Has no linked argument objects */
 151
 152                 return;
 153         }
 154
 155
 156         /* Append the argument to the linked argument list */
 157
 158         if (op->common.value.arg) {
 159                 /* Append to existing argument list */
 160
 161                 prev_arg = op->common.value.arg;
 162                 while (prev_arg->common.next) {
 163                         prev_arg = prev_arg->common.next;
 164                 }
 165                 prev_arg->common.next = arg;
 166         }
 167
 168         else {
 169                 /* No argument list, this will be the first argument */
 170
 171                 op->common.value.arg = arg;
 172         }
 173
 174
 175         /* Set the parent in this arg and any args linked after it */
 176
 177         while (arg) {
 178                 arg->common.parent = op;
 179                 arg = arg->common.next;
 180         }
 181 }
 182
 183
 184 /*******************************************************************************
 185  *
 186  * FUNCTION:    acpi_ps_get_child
 187  *
 188  * PARAMETERS:  Op              - Get the child of this Op
 189  *
 190  * RETURN:      Child Op, Null if none is found.
 191  *
 192  * DESCRIPTION: Get op's children or NULL if none
 193  *
 194  ******************************************************************************/
 195
 196 union acpi_parse_object *
 197 acpi_ps_get_child (
 198         union acpi_parse_object         *op)
 199 {
 200         union acpi_parse_object         *child = NULL;
 201
 202
 203         ACPI_FUNCTION_ENTRY ();
 204
 205
 206         switch (op->common.aml_opcode) {
 207         case AML_SCOPE_OP:
 208         case AML_ELSE_OP:
 209         case AML_DEVICE_OP:
 210         case AML_THERMAL_ZONE_OP:
 211         case AML_INT_METHODCALL_OP:
 212
 213                 child = acpi_ps_get_arg (op, 0);
 214                 break;
 215
 216
 217         case AML_BUFFER_OP:
 218         case AML_PACKAGE_OP:
 219         case AML_METHOD_OP:
 220         case AML_IF_OP:
 221         case AML_WHILE_OP:
 222         case AML_FIELD_OP:
 223
 224                 child = acpi_ps_get_arg (op, 1);
 225                 break;
 226
 227
 228         case AML_POWER_RES_OP:
 229         case AML_INDEX_FIELD_OP:
 230
 231                 child = acpi_ps_get_arg (op, 2);
 232                 break;
 233
 234
 235         case AML_PROCESSOR_OP:
 236         case AML_BANK_FIELD_OP:
 237
 238                 child = acpi_ps_get_arg (op, 3);
 239                 break;
 240
 241
 242         default:
 243                 /* All others have no children */
 244                 break;
 245         }
 246
 247         return (child);
 248 }
 249
 250
 251 /*******************************************************************************
 252  *
 253  * FUNCTION:    acpi_ps_get_depth_next
 254  *
 255  * PARAMETERS:  Origin          - Root of subtree to search
 256  *              Op              - Last (previous) Op that was found
 257  *
 258  * RETURN:      Next Op found in the search.
 259  *
 260  * DESCRIPTION: Get next op in tree (walking the tree in depth-first order)
 261  *              Return NULL when reaching "origin" or when walking up from root
 262  *
 263  ******************************************************************************/
 264
 265 union acpi_parse_object *
 266 acpi_ps_get_depth_next (
 267         union acpi_parse_object         *origin,
 268         union acpi_parse_object         *op)
 269 {
 270         union acpi_parse_object         *next = NULL;
 271         union acpi_parse_object         *parent;
 272         union acpi_parse_object         *arg;
 273
 274
 275         ACPI_FUNCTION_ENTRY ();
 276
 277
 278         if (!op) {
 279                 return (NULL);
 280         }
 281
 282         /* look for an argument or child */
 283
 284         next = acpi_ps_get_arg (op, 0);
 285         if (next) {
 286                 return (next);
 287         }
 288
 289         /* look for a sibling */
 290
 291         next = op->common.next;
 292         if (next) {
 293                 return (next);
 294         }
 295
 296         /* look for a sibling of parent */
 297
 298         parent = op->common.parent;
 299
 300         while (parent) {
 301                 arg = acpi_ps_get_arg (parent, 0);
 302                 while (arg && (arg != origin) && (arg != op)) {
 303                         arg = arg->common.next;
 304                 }
 305
 306                 if (arg == origin) {
 307                         /* reached parent of origin, end search */
 308
 309                         return (NULL);
 310                 }
 311
 312                 if (parent->common.next) {
 313                         /* found sibling of parent */
 314
 315                         return (parent->common.next);
 316                 }
 317
 318                 op = parent;
 319                 parent = parent->common.parent;
 320         }
 321
 322         return (next);
 323 }
 324
 325