drivers/acpi/namespace/nsxfobj.c

   1 /*******************************************************************************
   2  *
   3  * Module Name: nsxfobj - Public interfaces to the ACPI subsystem
   4  *                         ACPI Object oriented interfaces
   5  *
   6  ******************************************************************************/
   7
   8 /*
   9  * Copyright (C) 2000 - 2005, R. Byron Moore
  10  * All rights reserved.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions, and the following disclaimer,
  17  *    without modification.
  18  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  19  *    substantially similar to the "NO WARRANTY" disclaimer below
  20  *    ("Disclaimer") and any redistribution must be conditioned upon
  21  *    including a substantially similar Disclaimer requirement for further
  22  *    binary redistribution.
  23  * 3. Neither the names of the above-listed copyright holders nor the names
  24  *    of any contributors may be used to endorse or promote products derived
  25  *    from this software without specific prior written permission.
  26  *
  27  * Alternatively, this software may be distributed under the terms of the
  28  * GNU General Public License ("GPL") version 2 as published by the Free
  29  * Software Foundation.
  30  *
  31  * NO WARRANTY
  32  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  33  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  34  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  35  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  36  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  40  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  41  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  42  * POSSIBILITY OF SUCH DAMAGES.
  43  */
  44
  45 #include <linux/module.h>
  46
  47 #include <acpi/acpi.h>
  48 #include <acpi/acnamesp.h>
  49
  50
  51 #define _COMPONENT          ACPI_NAMESPACE
  52          ACPI_MODULE_NAME    ("nsxfobj")
  53
  54 /*******************************************************************************
  55  *
  56  * FUNCTION:    acpi_get_type
  57  *
  58  * PARAMETERS:  Handle          - Handle of object whose type is desired
  59  *              *ret_type       - Where the type will be placed
  60  *
  61  * RETURN:      Status
  62  *
  63  * DESCRIPTION: This routine returns the type associatd with a particular handle
  64  *
  65  ******************************************************************************/
  66
  67 acpi_status
  68 acpi_get_type (
  69         acpi_handle                     handle,
  70         acpi_object_type                *ret_type)
  71 {
  72         struct acpi_namespace_node      *node;
  73         acpi_status                     status;
  74
  75
  76         /* Parameter Validation */
  77
  78         if (!ret_type) {
  79                 return (AE_BAD_PARAMETER);
  80         }
  81
  82         /*
  83          * Special case for the predefined Root Node
  84          * (return type ANY)
  85          */
  86         if (handle == ACPI_ROOT_OBJECT) {
  87                 *ret_type = ACPI_TYPE_ANY;
  88                 return (AE_OK);
  89         }
  90
  91         status = acpi_ut_acquire_mutex (ACPI_MTX_NAMESPACE);
  92         if (ACPI_FAILURE (status)) {
  93                 return (status);
  94         }
  95
  96         /* Convert and validate the handle */
  97
  98         node = acpi_ns_map_handle_to_node (handle);
  99         if (!node) {
 100                 (void) acpi_ut_release_mutex (ACPI_MTX_NAMESPACE);
 101                 return (AE_BAD_PARAMETER);
 102         }
 103
 104         *ret_type = node->type;
 105
 106
 107         status = acpi_ut_release_mutex (ACPI_MTX_NAMESPACE);
 108         return (status);
 109 }
 110 EXPORT_SYMBOL(acpi_get_type);
 111
 112
 113 /*******************************************************************************
 114  *
 115  * FUNCTION:    acpi_get_parent
 116  *
 117  * PARAMETERS:  Handle          - Handle of object whose parent is desired
 118  *              ret_handle      - Where the parent handle will be placed
 119  *
 120  * RETURN:      Status
 121  *
 122  * DESCRIPTION: Returns a handle to the parent of the object represented by
 123  *              Handle.
 124  *
 125  ******************************************************************************/
 126
 127 acpi_status
 128 acpi_get_parent (
 129         acpi_handle                     handle,
 130         acpi_handle                     *ret_handle)
 131 {
 132         struct acpi_namespace_node      *node;
 133         acpi_status                     status;
 134
 135
 136         if (!ret_handle) {
 137                 return (AE_BAD_PARAMETER);
 138         }
 139
 140         /* Special case for the predefined Root Node (no parent) */
 141
 142         if (handle == ACPI_ROOT_OBJECT) {
 143                 return (AE_NULL_ENTRY);
 144         }
 145
 146         status = acpi_ut_acquire_mutex (ACPI_MTX_NAMESPACE);
 147         if (ACPI_FAILURE (status)) {
 148                 return (status);
 149         }
 150
 151         /* Convert and validate the handle */
 152
 153         node = acpi_ns_map_handle_to_node (handle);
 154         if (!node) {
 155                 status = AE_BAD_PARAMETER;
 156                 goto unlock_and_exit;
 157         }
 158
 159         /* Get the parent entry */
 160
 161         *ret_handle =
 162                 acpi_ns_convert_entry_to_handle (acpi_ns_get_parent_node (node));
 163
 164         /* Return exception if parent is null */
 165
 166         if (!acpi_ns_get_parent_node (node)) {
 167                 status = AE_NULL_ENTRY;
 168         }
 169
 170
 171 unlock_and_exit:
 172
 173         (void) acpi_ut_release_mutex (ACPI_MTX_NAMESPACE);
 174         return (status);
 175 }
 176 EXPORT_SYMBOL(acpi_get_parent);
 177
 178
 179 /*******************************************************************************
 180  *
 181  * FUNCTION:    acpi_get_next_object
 182  *
 183  * PARAMETERS:  Type            - Type of object to be searched for
 184  *              Parent          - Parent object whose children we are getting
 185  *              last_child      - Previous child that was found.
 186  *                                The NEXT child will be returned
 187  *              ret_handle      - Where handle to the next object is placed
 188  *
 189  * RETURN:      Status
 190  *
 191  * DESCRIPTION: Return the next peer object within the namespace.  If Handle is
 192  *              valid, Scope is ignored.  Otherwise, the first object within
 193  *              Scope is returned.
 194  *
 195  ******************************************************************************/
 196
 197 acpi_status
 198 acpi_get_next_object (
 199         acpi_object_type                type,
 200         acpi_handle                     parent,
 201         acpi_handle                     child,
 202         acpi_handle                     *ret_handle)
 203 {
 204         acpi_status                     status;
 205         struct acpi_namespace_node      *node;
 206         struct acpi_namespace_node      *parent_node = NULL;
 207         struct acpi_namespace_node      *child_node = NULL;
 208
 209
 210         /* Parameter validation */
 211
 212         if (type > ACPI_TYPE_EXTERNAL_MAX) {
 213                 return (AE_BAD_PARAMETER);
 214         }
 215
 216         status = acpi_ut_acquire_mutex (ACPI_MTX_NAMESPACE);
 217         if (ACPI_FAILURE (status)) {
 218                 return (status);
 219         }
 220
 221         /* If null handle, use the parent */
 222
 223         if (!child) {
 224                 /* Start search at the beginning of the specified scope */
 225
 226                 parent_node = acpi_ns_map_handle_to_node (parent);
 227                 if (!parent_node) {
 228                         status = AE_BAD_PARAMETER;
 229                         goto unlock_and_exit;
 230                 }
 231         }
 232         else {
 233                 /* Non-null handle, ignore the parent */
 234                 /* Convert and validate the handle */
 235
 236                 child_node = acpi_ns_map_handle_to_node (child);
 237                 if (!child_node) {
 238                         status = AE_BAD_PARAMETER;
 239                         goto unlock_and_exit;
 240                 }
 241         }
 242
 243         /* Internal function does the real work */
 244
 245         node = acpi_ns_get_next_node (type, parent_node, child_node);
 246         if (!node) {
 247                 status = AE_NOT_FOUND;
 248                 goto unlock_and_exit;
 249         }
 250
 251         if (ret_handle) {
 252                 *ret_handle = acpi_ns_convert_entry_to_handle (node);
 253         }
 254
 255
 256 unlock_and_exit:
 257
 258         (void) acpi_ut_release_mutex (ACPI_MTX_NAMESPACE);
 259         return (status);
 260 }
 261 EXPORT_SYMBOL(acpi_get_next_object);
 262