drivers/acpi/acpica/tbfind.c

   1 /******************************************************************************
   2  *
   3  * Module Name: tbfind   - find table
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2012, Intel Corp.
   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 "accommon.h"
  46 #include "actables.h"
  47
  48 #define _COMPONENT          ACPI_TABLES
  49 ACPI_MODULE_NAME("tbfind")
  50
  51 /*******************************************************************************
  52  *
  53  * FUNCTION:    acpi_tb_find_table
  54  *
  55  * PARAMETERS:  Signature           - String with ACPI table signature
  56  *              oem_id              - String with the table OEM ID
  57  *              oem_table_id        - String with the OEM Table ID
  58  *              table_index         - Where the table index is returned
  59  *
  60  * RETURN:      Status and table index
  61  *
  62  * DESCRIPTION: Find an ACPI table (in the RSDT/XSDT) that matches the
  63  *              Signature, OEM ID and OEM Table ID. Returns an index that can
  64  *              be used to get the table header or entire table.
  65  *
  66  ******************************************************************************/
  67 acpi_status
  68 acpi_tb_find_table(char *signature,
  69                    char *oem_id, char *oem_table_id, u32 *table_index)
  70 {
  71         u32 i;
  72         acpi_status status;
  73         struct acpi_table_header header;
  74
  75         ACPI_FUNCTION_TRACE(tb_find_table);
  76
  77         /* Normalize the input strings */
  78
  79         ACPI_MEMSET(&header, 0, sizeof(struct acpi_table_header));
  80         ACPI_STRNCPY(header.signature, signature, ACPI_NAME_SIZE);
  81         ACPI_STRNCPY(header.oem_id, oem_id, ACPI_OEM_ID_SIZE);
  82         ACPI_STRNCPY(header.oem_table_id, oem_table_id, ACPI_OEM_TABLE_ID_SIZE);
  83
  84         /* Search for the table */
  85
  86         for (i = 0; i < acpi_gbl_root_table_list.current_table_count; ++i) {
  87                 if (ACPI_MEMCMP(&(acpi_gbl_root_table_list.tables[i].signature),
  88                                 header.signature, ACPI_NAME_SIZE)) {
  89
  90                         /* Not the requested table */
  91
  92                         continue;
  93                 }
  94
  95                 /* Table with matching signature has been found */
  96
  97                 if (!acpi_gbl_root_table_list.tables[i].pointer) {
  98
  99                         /* Table is not currently mapped, map it */
 100
 101                         status =
 102                             acpi_tb_verify_table(&acpi_gbl_root_table_list.
 103                                                  tables[i]);
 104                         if (ACPI_FAILURE(status)) {
 105                                 return_ACPI_STATUS(status);
 106                         }
 107
 108                         if (!acpi_gbl_root_table_list.tables[i].pointer) {
 109                                 continue;
 110                         }
 111                 }
 112
 113                 /* Check for table match on all IDs */
 114
 115                 if (!ACPI_MEMCMP
 116                     (acpi_gbl_root_table_list.tables[i].pointer->signature,
 117                      header.signature, ACPI_NAME_SIZE) && (!oem_id[0]
 118                                                            ||
 119                                                            !ACPI_MEMCMP
 120                                                            (acpi_gbl_root_table_list.
 121                                                             tables[i].pointer->
 122                                                             oem_id,
 123                                                             header.oem_id,
 124                                                             ACPI_OEM_ID_SIZE))
 125                     && (!oem_table_id[0]
 126                         || !ACPI_MEMCMP(acpi_gbl_root_table_list.tables[i].
 127                                         pointer->oem_table_id,
 128                                         header.oem_table_id,
 129                                         ACPI_OEM_TABLE_ID_SIZE))) {
 130                         *table_index = i;
 131
 132                         ACPI_DEBUG_PRINT((ACPI_DB_TABLES,
 133                                           "Found table [%4.4s]\n",
 134                                           header.signature));
 135                         return_ACPI_STATUS(AE_OK);
 136                 }
 137         }
 138
 139         return_ACPI_STATUS(AE_NOT_FOUND);
 140 }