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 - 2013, 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 #include "amlresrc.h"
  50
  51 #define _COMPONENT          ACPI_NAMESPACE
  52 ACPI_MODULE_NAME("nsrepair")
  53
  54 /*******************************************************************************
  55  *
  56  * This module attempts to repair or convert objects returned by the
  57  * predefined methods to an object type that is expected, as per the ACPI
  58  * specification. The need for this code is dictated by the many machines that
  59  * return incorrect types for the standard predefined methods. Performing these
  60  * conversions here, in one place, eliminates the need for individual ACPI
  61  * device drivers to do the same. Note: Most of these conversions are different
  62  * than the internal object conversion routines used for implicit object
  63  * conversion.
  64  *
  65  * The following conversions can be performed as necessary:
  66  *
  67  * Integer -> String
  68  * Integer -> Buffer
  69  * String  -> Integer
  70  * String  -> Buffer
  71  * Buffer  -> Integer
  72  * Buffer  -> String
  73  * Buffer  -> Package of Integers
  74  * Package -> Package of one Package
  75  *
  76  * Additional conversions that are available:
  77  *  Convert a null return or zero return value to an end_tag descriptor
  78  *  Convert an ASCII string to a Unicode buffer
  79  *
  80  * An incorrect standalone object is wrapped with required outer package
  81  *
  82  * Additional possible repairs:
  83  * Required package elements that are NULL replaced by Integer/String/Buffer
  84  *
  85  ******************************************************************************/
  86 /* Local prototypes */
  87 static const struct acpi_simple_repair_info *acpi_ns_match_simple_repair(struct
  88                                                                          acpi_namespace_node
  89                                                                          *node,
  90                                                                          u32
  91                                                                          return_btype,
  92                                                                          u32
  93                                                                          package_index);
  94
  95 /*
  96  * Special but simple repairs for some names.
  97  *
  98  * 2nd argument: Unexpected types that can be repaired
  99  */
 100 static const struct acpi_simple_repair_info acpi_object_repair_info[] = {
 101         /* Unicode conversions */
 102
 103         {"_MLS", ACPI_RTYPE_STRING, 1,
 104          acpi_ns_convert_to_unicode},
 105         {"_STR", ACPI_RTYPE_STRING | ACPI_RTYPE_BUFFER,
 106          ACPI_NOT_PACKAGE_ELEMENT,
 107          acpi_ns_convert_to_unicode},
 108         {{0, 0, 0, 0}, 0, 0, NULL}      /* Table terminator */
 109 };
 110
 111 /*******************************************************************************
 112  *
 113  * FUNCTION:    acpi_ns_simple_repair
 114  *
 115  * PARAMETERS:  data                - Pointer to validation data structure
 116  *              expected_btypes     - Object types expected
 117  *              package_index       - Index of object within parent package (if
 118  *                                    applicable - ACPI_NOT_PACKAGE_ELEMENT
 119  *                                    otherwise)
 120  *              return_object_ptr   - Pointer to the object returned from the
 121  *                                    evaluation of a method or object
 122  *
 123  * RETURN:      Status. AE_OK if repair was successful.
 124  *
 125  * DESCRIPTION: Attempt to repair/convert a return object of a type that was
 126  *              not expected.
 127  *
 128  ******************************************************************************/
 129
 130 acpi_status
 131 acpi_ns_simple_repair(struct acpi_predefined_data *data,
 132                       u32 expected_btypes,
 133                       u32 package_index,
 134                       union acpi_operand_object **return_object_ptr)
 135 {
 136         union acpi_operand_object *return_object = *return_object_ptr;
 137         union acpi_operand_object *new_object = NULL;
 138         acpi_status status;
 139         const struct acpi_simple_repair_info *predefined;
 140
 141         ACPI_FUNCTION_NAME(ns_simple_repair);
 142
 143         /*
 144          * Special repairs for certain names that are in the repair table.
 145          * Check if this name is in the list of repairable names.
 146          */
 147         predefined = acpi_ns_match_simple_repair(data->node,
 148                                                  data->return_btype,
 149                                                  package_index);
 150         if (predefined) {
 151                 if (!return_object) {
 152                         ACPI_WARN_PREDEFINED((AE_INFO, data->pathname,
 153                                               ACPI_WARN_ALWAYS,
 154                                               "Missing expected return value"));
 155                 }
 156
 157                 status =
 158                     predefined->object_converter(return_object, &new_object);
 159                 if (ACPI_FAILURE(status)) {
 160
 161                         /* A fatal error occurred during a conversion */
 162
 163                         ACPI_EXCEPTION((AE_INFO, status,
 164                                         "During return object analysis"));
 165                         return (status);
 166                 }
 167                 if (new_object) {
 168                         goto object_repaired;
 169                 }
 170         }
 171
 172         /*
 173          * Do not perform simple object repair unless the return type is not
 174          * expected.
 175          */
 176         if (data->return_btype & expected_btypes) {
 177                 return (AE_OK);
 178         }
 179
 180         /*
 181          * At this point, we know that the type of the returned object was not
 182          * one of the expected types for this predefined name. Attempt to
 183          * repair the object by converting it to one of the expected object
 184          * types for this predefined name.
 185          */
 186
 187         /*
 188          * If there is no return value, check if we require a return value for
 189          * this predefined name. Either one return value is expected, or none,
 190          * for both methods and other objects.
 191          *
 192          * Exit now if there is no return object. Warning if one was expected.
 193          */
 194         if (!return_object) {
 195                 if (expected_btypes && (!(expected_btypes & ACPI_RTYPE_NONE))) {
 196                         ACPI_WARN_PREDEFINED((AE_INFO, data->pathname,
 197                                               ACPI_WARN_ALWAYS,
 198                                               "Missing expected return value"));
 199
 200                         return (AE_AML_NO_RETURN_VALUE);
 201                 }
 202         }
 203
 204         if (expected_btypes & ACPI_RTYPE_INTEGER) {
 205                 status = acpi_ns_convert_to_integer(return_object, &new_object);
 206                 if (ACPI_SUCCESS(status)) {
 207                         goto object_repaired;
 208                 }
 209         }
 210         if (expected_btypes & ACPI_RTYPE_STRING) {
 211                 status = acpi_ns_convert_to_string(return_object, &new_object);
 212                 if (ACPI_SUCCESS(status)) {
 213                         goto object_repaired;
 214                 }
 215         }
 216         if (expected_btypes & ACPI_RTYPE_BUFFER) {
 217                 status = acpi_ns_convert_to_buffer(return_object, &new_object);
 218                 if (ACPI_SUCCESS(status)) {
 219                         goto object_repaired;
 220                 }
 221         }
 222         if (expected_btypes & ACPI_RTYPE_PACKAGE) {
 223                 /*
 224                  * A package is expected. We will wrap the existing object with a
 225                  * new package object. It is often the case that if a variable-length
 226                  * package is required, but there is only a single object needed, the
 227                  * BIOS will return that object instead of wrapping it with a Package
 228                  * object. Note: after the wrapping, the package will be validated
 229                  * for correct contents (expected object type or types).
 230                  */
 231                 status =
 232                     acpi_ns_wrap_with_package(data, return_object, &new_object);
 233                 if (ACPI_SUCCESS(status)) {
 234                         /*
 235                          * The original object just had its reference count
 236                          * incremented for being inserted into the new package.
 237                          */
 238                         *return_object_ptr = new_object;        /* New Package object */
 239                         data->flags |= ACPI_OBJECT_REPAIRED;
 240                         return (AE_OK);
 241                 }
 242         }
 243
 244         /* We cannot repair this object */
 245
 246         return (AE_AML_OPERAND_TYPE);
 247
 248       object_repaired:
 249
 250         /* Object was successfully repaired */
 251
 252         if (package_index != ACPI_NOT_PACKAGE_ELEMENT) {
 253                 /*
 254                  * The original object is a package element. We need to
 255                  * decrement the reference count of the original object,
 256                  * for removing it from the package.
 257                  *
 258                  * However, if the original object was just wrapped with a
 259                  * package object as part of the repair, we don't need to
 260                  * change the reference count.
 261                  */
 262                 if (!(data->flags & ACPI_OBJECT_WRAPPED)) {
 263                         new_object->common.reference_count =
 264                             return_object->common.reference_count;
 265
 266                         if (return_object->common.reference_count > 1) {
 267                                 return_object->common.reference_count--;
 268                         }
 269                 }
 270
 271                 ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
 272                                   "%s: Converted %s to expected %s at Package index %u\n",
 273                                   data->pathname,
 274                                   acpi_ut_get_object_type_name(return_object),
 275                                   acpi_ut_get_object_type_name(new_object),
 276                                   package_index));
 277         } else {
 278                 ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
 279                                   "%s: Converted %s to expected %s\n",
 280                                   data->pathname,
 281                                   acpi_ut_get_object_type_name(return_object),
 282                                   acpi_ut_get_object_type_name(new_object)));
 283         }
 284
 285         /* Delete old object, install the new return object */
 286
 287         acpi_ut_remove_reference(return_object);
 288         *return_object_ptr = new_object;
 289         data->flags |= ACPI_OBJECT_REPAIRED;
 290         return (AE_OK);
 291 }
 292
 293 /******************************************************************************
 294  *
 295  * FUNCTION:    acpi_ns_match_simple_repair
 296  *
 297  * PARAMETERS:  node                - Namespace node for the method/object
 298  *              return_btype        - Object type that was returned
 299  *              package_index       - Index of object within parent package (if
 300  *                                    applicable - ACPI_NOT_PACKAGE_ELEMENT
 301  *                                    otherwise)
 302  *
 303  * RETURN:      Pointer to entry in repair table. NULL indicates not found.
 304  *
 305  * DESCRIPTION: Check an object name against the repairable object list.
 306  *
 307  *****************************************************************************/
 308
 309 static const struct acpi_simple_repair_info *acpi_ns_match_simple_repair(struct
 310                                                                          acpi_namespace_node
 311                                                                          *node,
 312                                                                          u32
 313                                                                          return_btype,
 314                                                                          u32
 315                                                                          package_index)
 316 {
 317         const struct acpi_simple_repair_info *this_name;
 318
 319         /* Search info table for a repairable predefined method/object name */
 320
 321         this_name = acpi_object_repair_info;
 322         while (this_name->object_converter) {
 323                 if (ACPI_COMPARE_NAME(node->name.ascii, this_name->name)) {
 324
 325                         /* Check if we can actually repair this name/type combination */
 326
 327                         if ((return_btype & this_name->unexpected_btypes) &&
 328                             (package_index == this_name->package_index)) {
 329                                 return (this_name);
 330                         }
 331
 332                         return (NULL);
 333                 }
 334                 this_name++;
 335         }
 336
 337         return (NULL);          /* Name was not found in the repair table */
 338 }
 339
 340 /*******************************************************************************
 341  *
 342  * FUNCTION:    acpi_ns_repair_null_element
 343  *
 344  * PARAMETERS:  data                - Pointer to validation data structure
 345  *              expected_btypes     - Object types expected
 346  *              package_index       - Index of object within parent package (if
 347  *                                    applicable - ACPI_NOT_PACKAGE_ELEMENT
 348  *                                    otherwise)
 349  *              return_object_ptr   - Pointer to the object returned from the
 350  *                                    evaluation of a method or object
 351  *
 352  * RETURN:      Status. AE_OK if repair was successful.
 353  *
 354  * DESCRIPTION: Attempt to repair a NULL element of a returned Package object.
 355  *
 356  ******************************************************************************/
 357
 358 acpi_status
 359 acpi_ns_repair_null_element(struct acpi_predefined_data *data,
 360                             u32 expected_btypes,
 361                             u32 package_index,
 362                             union acpi_operand_object **return_object_ptr)
 363 {
 364         union acpi_operand_object *return_object = *return_object_ptr;
 365         union acpi_operand_object *new_object;
 366
 367         ACPI_FUNCTION_NAME(ns_repair_null_element);
 368
 369         /* No repair needed if return object is non-NULL */
 370
 371         if (return_object) {
 372                 return (AE_OK);
 373         }
 374
 375         /*
 376          * Attempt to repair a NULL element of a Package object. This applies to
 377          * predefined names that return a fixed-length package and each element
 378          * is required. It does not apply to variable-length packages where NULL
 379          * elements are allowed, especially at the end of the package.
 380          */
 381         if (expected_btypes & ACPI_RTYPE_INTEGER) {
 382
 383                 /* Need an integer - create a zero-value integer */
 384
 385                 new_object = acpi_ut_create_integer_object((u64)0);
 386         } else if (expected_btypes & ACPI_RTYPE_STRING) {
 387
 388                 /* Need a string - create a NULL string */
 389
 390                 new_object = acpi_ut_create_string_object(0);
 391         } else if (expected_btypes & ACPI_RTYPE_BUFFER) {
 392
 393                 /* Need a buffer - create a zero-length buffer */
 394
 395                 new_object = acpi_ut_create_buffer_object(0);
 396         } else {
 397                 /* Error for all other expected types */
 398
 399                 return (AE_AML_OPERAND_TYPE);
 400         }
 401
 402         if (!new_object) {
 403                 return (AE_NO_MEMORY);
 404         }
 405
 406         /* Set the reference count according to the parent Package object */
 407
 408         new_object->common.reference_count =
 409             data->parent_package->common.reference_count;
 410
 411         ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
 412                           "%s: Converted NULL package element to expected %s at index %u\n",
 413                           data->pathname,
 414                           acpi_ut_get_object_type_name(new_object),
 415                           package_index));
 416
 417         *return_object_ptr = new_object;
 418         data->flags |= ACPI_OBJECT_REPAIRED;
 419         return (AE_OK);
 420 }
 421
 422 /******************************************************************************
 423  *
 424  * FUNCTION:    acpi_ns_remove_null_elements
 425  *
 426  * PARAMETERS:  data                - Pointer to validation data structure
 427  *              package_type        - An acpi_return_package_types value
 428  *              obj_desc            - A Package object
 429  *
 430  * RETURN:      None.
 431  *
 432  * DESCRIPTION: Remove all NULL package elements from packages that contain
 433  *              a variable number of sub-packages. For these types of
 434  *              packages, NULL elements can be safely removed.
 435  *
 436  *****************************************************************************/
 437
 438 void
 439 acpi_ns_remove_null_elements(struct acpi_predefined_data *data,
 440                              u8 package_type,
 441                              union acpi_operand_object *obj_desc)
 442 {
 443         union acpi_operand_object **source;
 444         union acpi_operand_object **dest;
 445         u32 count;
 446         u32 new_count;
 447         u32 i;
 448
 449         ACPI_FUNCTION_NAME(ns_remove_null_elements);
 450
 451         /*
 452          * We can safely remove all NULL elements from these package types:
 453          * PTYPE1_VAR packages contain a variable number of simple data types.
 454          * PTYPE2 packages contain a variable number of sub-packages.
 455          */
 456         switch (package_type) {
 457         case ACPI_PTYPE1_VAR:
 458         case ACPI_PTYPE2:
 459         case ACPI_PTYPE2_COUNT:
 460         case ACPI_PTYPE2_PKG_COUNT:
 461         case ACPI_PTYPE2_FIXED:
 462         case ACPI_PTYPE2_MIN:
 463         case ACPI_PTYPE2_REV_FIXED:
 464         case ACPI_PTYPE2_FIX_VAR:
 465                 break;
 466
 467         default:
 468         case ACPI_PTYPE1_FIXED:
 469         case ACPI_PTYPE1_OPTION:
 470                 return;
 471         }
 472
 473         count = obj_desc->package.count;
 474         new_count = count;
 475
 476         source = obj_desc->package.elements;
 477         dest = source;
 478
 479         /* Examine all elements of the package object, remove nulls */
 480
 481         for (i = 0; i < count; i++) {
 482                 if (!*source) {
 483                         new_count--;
 484                 } else {
 485                         *dest = *source;
 486                         dest++;
 487                 }
 488                 source++;
 489         }
 490
 491         /* Update parent package if any null elements were removed */
 492
 493         if (new_count < count) {
 494                 ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
 495                                   "%s: Found and removed %u NULL elements\n",
 496                                   data->pathname, (count - new_count)));
 497
 498                 /* NULL terminate list and update the package count */
 499
 500                 *dest = NULL;
 501                 obj_desc->package.count = new_count;
 502         }
 503 }
 504
 505 /*******************************************************************************
 506  *
 507  * FUNCTION:    acpi_ns_wrap_with_package
 508  *
 509  * PARAMETERS:  data                - Pointer to validation data structure
 510  *              original_object     - Pointer to the object to repair.
 511  *              obj_desc_ptr        - The new package object is returned here
 512  *
 513  * RETURN:      Status, new object in *obj_desc_ptr
 514  *
 515  * DESCRIPTION: Repair a common problem with objects that are defined to
 516  *              return a variable-length Package of sub-objects. If there is
 517  *              only one sub-object, some BIOS code mistakenly simply declares
 518  *              the single object instead of a Package with one sub-object.
 519  *              This function attempts to repair this error by wrapping a
 520  *              Package object around the original object, creating the
 521  *              correct and expected Package with one sub-object.
 522  *
 523  *              Names that can be repaired in this manner include:
 524  *              _ALR, _CSD, _HPX, _MLS, _PLD, _PRT, _PSS, _TRT, _TSS,
 525  *              _BCL, _DOD, _FIX, _Sx
 526  *
 527  ******************************************************************************/
 528
 529 acpi_status
 530 acpi_ns_wrap_with_package(struct acpi_predefined_data *data,
 531                           union acpi_operand_object *original_object,
 532                           union acpi_operand_object **obj_desc_ptr)
 533 {
 534         union acpi_operand_object *pkg_obj_desc;
 535
 536         ACPI_FUNCTION_NAME(ns_wrap_with_package);
 537
 538         /*
 539          * Create the new outer package and populate it. The new package will
 540          * have a single element, the lone sub-object.
 541          */
 542         pkg_obj_desc = acpi_ut_create_package_object(1);
 543         if (!pkg_obj_desc) {
 544                 return (AE_NO_MEMORY);
 545         }
 546
 547         pkg_obj_desc->package.elements[0] = original_object;
 548
 549         ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
 550                           "%s: Wrapped %s with expected Package object\n",
 551                           data->pathname,
 552                           acpi_ut_get_object_type_name(original_object)));
 553
 554         /* Return the new object in the object pointer */
 555
 556         *obj_desc_ptr = pkg_obj_desc;
 557         data->flags |= ACPI_OBJECT_REPAIRED | ACPI_OBJECT_WRAPPED;
 558         return (AE_OK);
 559 }