drivers/acpi/acpica/nsrepair.c

   1 /******************************************************************************
   2  *
   3  * Module Name: nsrepair - Repair for objects returned by predefined methods
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2009, 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 "acnamesp.h"
  47 #include "acinterp.h"
  48 #include "acpredef.h"
  49
  50 #define _COMPONENT          ACPI_NAMESPACE
  51 ACPI_MODULE_NAME("nsrepair")
  52
  53 /*******************************************************************************
  54  *
  55  * FUNCTION:    acpi_ns_repair_object
  56  *
  57  * PARAMETERS:  Data                - Pointer to validation data structure
  58  *              expected_btypes     - Object types expected
  59  *              package_index       - Index of object within parent package (if
  60  *                                    applicable - ACPI_NOT_PACKAGE_ELEMENT
  61  *                                    otherwise)
  62  *              return_object_ptr   - Pointer to the object returned from the
  63  *                                    evaluation of a method or object
  64  *
  65  * RETURN:      Status. AE_OK if repair was successful.
  66  *
  67  * DESCRIPTION: Attempt to repair/convert a return object of a type that was
  68  *              not expected.
  69  *
  70  ******************************************************************************/
  71 acpi_status
  72 acpi_ns_repair_object(struct acpi_predefined_data *data,
  73                       u32 expected_btypes,
  74                       u32 package_index,
  75                       union acpi_operand_object **return_object_ptr)
  76 {
  77         union acpi_operand_object *return_object = *return_object_ptr;
  78         union acpi_operand_object *new_object;
  79         acpi_size length;
  80         acpi_status status;
  81
  82         /*
  83          * At this point, we know that the type of the returned object was not
  84          * one of the expected types for this predefined name. Attempt to
  85          * repair the object. Only a limited number of repairs are possible.
  86          */
  87         switch (return_object->common.type) {
  88         case ACPI_TYPE_BUFFER:
  89
  90                 /* Does the method/object legally return a string? */
  91
  92                 if (!(expected_btypes & ACPI_RTYPE_STRING)) {
  93                         return (AE_AML_OPERAND_TYPE);
  94                 }
  95
  96                 /*
  97                  * Have a Buffer, expected a String, convert. Use a to_string
  98                  * conversion, no transform performed on the buffer data. The best
  99                  * example of this is the _BIF method, where the string data from
 100                  * the battery is often (incorrectly) returned as buffer object(s).
 101                  */
 102                 length = 0;
 103                 while ((length < return_object->buffer.length) &&
 104                        (return_object->buffer.pointer[length])) {
 105                         length++;
 106                 }
 107
 108                 /* Allocate a new string object */
 109
 110                 new_object = acpi_ut_create_string_object(length);
 111                 if (!new_object) {
 112                         return (AE_NO_MEMORY);
 113                 }
 114
 115                 /*
 116                  * Copy the raw buffer data with no transform. String is already NULL
 117                  * terminated at Length+1.
 118                  */
 119                 ACPI_MEMCPY(new_object->string.pointer,
 120                             return_object->buffer.pointer, length);
 121                 break;
 122
 123         case ACPI_TYPE_INTEGER:
 124
 125                 /* 1) Does the method/object legally return a buffer? */
 126
 127                 if (expected_btypes & ACPI_RTYPE_BUFFER) {
 128                         /*
 129                          * Convert the Integer to a packed-byte buffer. _MAT needs
 130                          * this sometimes, if a read has been performed on a Field
 131                          * object that is less than or equal to the global integer
 132                          * size (32 or 64 bits).
 133                          */
 134                         status =
 135                             acpi_ex_convert_to_buffer(return_object,
 136                                                       &new_object);
 137                         if (ACPI_FAILURE(status)) {
 138                                 return (status);
 139                         }
 140                 }
 141
 142                 /* 2) Does the method/object legally return a string? */
 143
 144                 else if (expected_btypes & ACPI_RTYPE_STRING) {
 145                         /*
 146                          * The only supported Integer-to-String conversion is to convert
 147                          * an integer of value 0 to a NULL string. The last element of
 148                          * _BIF and _BIX packages occasionally need this fix.
 149                          */
 150                         if (return_object->integer.value != 0) {
 151                                 return (AE_AML_OPERAND_TYPE);
 152                         }
 153
 154                         /* Allocate a new NULL string object */
 155
 156                         new_object = acpi_ut_create_string_object(0);
 157                         if (!new_object) {
 158                                 return (AE_NO_MEMORY);
 159                         }
 160                 } else {
 161                         return (AE_AML_OPERAND_TYPE);
 162                 }
 163                 break;
 164
 165         default:
 166
 167                 /* We cannot repair this object */
 168
 169                 return (AE_AML_OPERAND_TYPE);
 170         }
 171
 172         /* Object was successfully repaired */
 173
 174         /*
 175          * If the original object is a package element, we need to:
 176          * 1. Set the reference count of the new object to match the
 177          *    reference count of the old object.
 178          * 2. Decrement the reference count of the original object.
 179          */
 180         if (package_index != ACPI_NOT_PACKAGE_ELEMENT) {
 181                 new_object->common.reference_count =
 182                     return_object->common.reference_count;
 183
 184                 if (return_object->common.reference_count > 1) {
 185                         return_object->common.reference_count--;
 186                 }
 187
 188                 ACPI_INFO_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
 189                                       "Converted %s to expected %s at index %u",
 190                                       acpi_ut_get_object_type_name
 191                                       (return_object),
 192                                       acpi_ut_get_object_type_name(new_object),
 193                                       package_index));
 194         } else {
 195                 ACPI_INFO_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
 196                                       "Converted %s to expected %s",
 197                                       acpi_ut_get_object_type_name
 198                                       (return_object),
 199                                       acpi_ut_get_object_type_name
 200                                       (new_object)));
 201         }
 202
 203         /* Delete old object, install the new return object */
 204
 205         acpi_ut_remove_reference(return_object);
 206         *return_object_ptr = new_object;
 207         data->flags |= ACPI_OBJECT_REPAIRED;
 208         return (AE_OK);
 209 }
 210
 211 /*******************************************************************************
 212  *
 213  * FUNCTION:    acpi_ns_repair_package_list
 214  *
 215  * PARAMETERS:  Data                - Pointer to validation data structure
 216  *              obj_desc_ptr        - Pointer to the object to repair. The new
 217  *                                    package object is returned here,
 218  *                                    overwriting the old object.
 219  *
 220  * RETURN:      Status, new object in *obj_desc_ptr
 221  *
 222  * DESCRIPTION: Repair a common problem with objects that are defined to return
 223  *              a variable-length Package of Packages. If the variable-length
 224  *              is one, some BIOS code mistakenly simply declares a single
 225  *              Package instead of a Package with one sub-Package. This
 226  *              function attempts to repair this error by wrapping a Package
 227  *              object around the original Package, creating the correct
 228  *              Package with one sub-Package.
 229  *
 230  *              Names that can be repaired in this manner include:
 231  *              _ALR, _CSD, _HPX, _MLS, _PRT, _PSS, _TRT, TSS
 232  *
 233  ******************************************************************************/
 234
 235 acpi_status
 236 acpi_ns_repair_package_list(struct acpi_predefined_data *data,
 237                             union acpi_operand_object **obj_desc_ptr)
 238 {
 239         union acpi_operand_object *pkg_obj_desc;
 240
 241         /*
 242          * Create the new outer package and populate it. The new package will
 243          * have a single element, the lone subpackage.
 244          */
 245         pkg_obj_desc = acpi_ut_create_package_object(1);
 246         if (!pkg_obj_desc) {
 247                 return (AE_NO_MEMORY);
 248         }
 249
 250         pkg_obj_desc->package.elements[0] = *obj_desc_ptr;
 251
 252         /* Return the new object in the object pointer */
 253
 254         *obj_desc_ptr = pkg_obj_desc;
 255         data->flags |= ACPI_OBJECT_REPAIRED;
 256
 257         ACPI_INFO_PREDEFINED((AE_INFO, data->pathname, data->node_flags,
 258                               "Repaired Incorrectly formed Package"));
 259
 260         return (AE_OK);
 261 }