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 - 2005, 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 #ifdef ACPI_FUTURE_USAGE
 185
 186 /*******************************************************************************
 187  *
 188  * FUNCTION:    acpi_ps_get_child
 189  *
 190  * PARAMETERS:  Op              - Get the child of this Op
 191  *
 192  * RETURN:      Child Op, Null if none is found.
 193  *
 194  * DESCRIPTION: Get op's children or NULL if none
 195  *
 196  ******************************************************************************/
 197 union acpi_parse_object *
 198 acpi_ps_get_child (
 199         union acpi_parse_object         *op)
 200 {
 201         union acpi_parse_object         *child = NULL;
 202
 203
 204         ACPI_FUNCTION_ENTRY ();
 205
 206
 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:
 213
 214                 child = acpi_ps_get_arg (op, 0);
 215                 break;
 216
 217
 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:
 224
 225                 child = acpi_ps_get_arg (op, 1);
 226                 break;
 227
 228
 229         case AML_POWER_RES_OP:
 230         case AML_INDEX_FIELD_OP:
 231
 232                 child = acpi_ps_get_arg (op, 2);
 233                 break;
 234
 235
 236         case AML_PROCESSOR_OP:
 237         case AML_BANK_FIELD_OP:
 238
 239                 child = acpi_ps_get_arg (op, 3);
 240                 break;
 241
 242
 243         default:
 244                 /* All others have no children */
 245                 break;
 246         }
 247
 248         return (child);
 249 }
 250
 251
 252 /*******************************************************************************
 253  *
 254  * FUNCTION:    acpi_ps_get_depth_next
 255  *
 256  * PARAMETERS:  Origin          - Root of subtree to search
 257  *              Op              - Last (previous) Op that was found
 258  *
 259  * RETURN:      Next Op found in the search.
 260  *
 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
 263  *
 264  ******************************************************************************/
 265
 266 union acpi_parse_object *
 267 acpi_ps_get_depth_next (
 268         union acpi_parse_object         *origin,
 269         union acpi_parse_object         *op)
 270 {
 271         union acpi_parse_object         *next = NULL;
 272         union acpi_parse_object         *parent;
 273         union acpi_parse_object         *arg;
 274
 275
 276         ACPI_FUNCTION_ENTRY ();
 277
 278
 279         if (!op) {
 280                 return (NULL);
 281         }
 282
 283         /* look for an argument or child */
 284
 285         next = acpi_ps_get_arg (op, 0);
 286         if (next) {
 287                 return (next);
 288         }
 289
 290         /* look for a sibling */
 291
 292         next = op->common.next;
 293         if (next) {
 294                 return (next);
 295         }
 296
 297         /* look for a sibling of parent */
 298
 299         parent = op->common.parent;
 300
 301         while (parent) {
 302                 arg = acpi_ps_get_arg (parent, 0);
 303                 while (arg && (arg != origin) && (arg != op)) {
 304                         arg = arg->common.next;
 305                 }
 306
 307                 if (arg == origin) {
 308                         /* reached parent of origin, end search */
 309
 310                         return (NULL);
 311                 }
 312
 313                 if (parent->common.next) {
 314                         /* found sibling of parent */
 315
 316                         return (parent->common.next);
 317                 }
 318
 319                 op = parent;
 320                 parent = parent->common.parent;
 321         }
 322
 323         return (next);
 324 }
 325
 326 #endif  /*  ACPI_FUTURE_USAGE  */
 327