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 - 2011, 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  * This module attempts to repair or convert objects returned by the
  56  * predefined methods to an object type that is expected, as per the ACPI
  57  * specification. The need for this code is dictated by the many machines that
  58  * return incorrect types for the standard predefined methods. Performing these
  59  * conversions here, in one place, eliminates the need for individual ACPI
  60  * device drivers to do the same. Note: Most of these conversions are different
  61  * than the internal object conversion routines used for implicit object
  62  * conversion.
  63  *
  64  * The following conversions can be performed as necessary:
  65  *
  66  * Integer -> String
  67  * Integer -> Buffer
  68  * String  -> Integer
  69  * String  -> Buffer
  70  * Buffer  -> Integer
  71  * Buffer  -> String
  72  * Buffer  -> Package of Integers
  73  * Package -> Package of one Package
  74  *
  75  * Additional possible repairs:
  76  *
  77  * Required package elements that are NULL replaced by Integer/String/Buffer
  78  * Incorrect standalone package wrapped with required outer package
  79  *
  80  ******************************************************************************/
  81 /* Local prototypes */
  82 static acpi_status
  83 acpi_ns_convert_to_integer(union acpi_operand_object *original_object,
  84                            union acpi_operand_object **return_object);
  85
  86 static acpi_status
  87 acpi_ns_convert_to_string(union acpi_operand_object *original_object,
  88                           union acpi_operand_object **return_object);
  89
  90 static acpi_status
  91 acpi_ns_convert_to_buffer(union acpi_operand_object *original_object,
  92                           union acpi_operand_object **return_object);
  93
  94 static acpi_status
  95 acpi_ns_convert_to_package(union acpi_operand_object *original_object,
  96                            union acpi_operand_object **return_object);
  97
  98 /*******************************************************************************
  99  *
 100  * FUNCTION:    acpi_ns_repair_object
 101  *
 102  * PARAMETERS:  Data                - Pointer to validation data structure
 103  *              expected_btypes     - Object types expected
 104  *              package_index       - Index of object within parent package (if
 105  *                                    applicable - ACPI_NOT_PACKAGE_ELEMENT
 106  *                                    otherwise)
 107  *              return_object_ptr   - Pointer to the object returned from the
 108  *                                    evaluation of a method or object
 109  *
 110  * RETURN:      Status. AE_OK if repair was successful.
 111  *
 112  * DESCRIPTION: Attempt to repair/convert a return object of a type that was
 113  *              not expected.
 114  *
 115  ******************************************************************************/
 116
 117 acpi_status
 118 acpi_ns_repair_object(struct acpi_predefined_data *data,
 119                       u32 expected_btypes,
 120                       u32 package_index,
 121                       union acpi_operand_object **return_object_ptr)
 122 {
 123         union acpi_operand_object *return_object = *return_object_ptr;
 124         union acpi_operand_object *new_object;
 125         acpi_status status;
 126
 127         ACPI_FUNCTION_NAME(ns_repair_object);
 128
 129         /*
 130          * At this point, we know that the type of the returned object was not
 131          * one of the expected types for this predefined name. Attempt to
 132          * repair the object by converting it to one of the expected object
 133          * types for this predefined name.
 134          */
 135         if (expected_btypes & ACPI_RTYPE_INTEGER) {
 136                 status = acpi_ns_convert_to_integer(return_object, &new_object);
 137                 if (ACPI_SUCCESS(status)) {
 138                         goto object_repaired;
 139                 }
 140         }
 141         if (expected_btypes & ACPI_RTYPE_STRING) {
 142                 status = acpi_ns_convert_to_string(return_object, &new_object);
 143                 if (ACPI_SUCCESS(status)) {
 144                         goto object_repaired;
 145                 }
 146         }
 147         if (expected_btypes & ACPI_RTYPE_BUFFER) {
 148                 status = acpi_ns_convert_to_buffer(return_object, &new_object);
 149                 if (ACPI_SUCCESS(status)) {
 150                         goto object_repaired;
 151                 }
 152         }
 153         if (expected_btypes & ACPI_RTYPE_PACKAGE) {
 154                 status = acpi_ns_convert_to_package(return_object, &new_object);
 155                 if (ACPI_SUCCESS(status)) {
 156                         goto object_repaired;
 157                 }
 158         }
 159
 160         /* We cannot repair this object */
 161
 162         return (AE_AML_OPERAND_TYPE);
 163
 164       object_repaired:
 165
 166         /* Object was successfully repaired */
 167
 168         /*
 169          * If the original object is a package element, we need to:
 170          * 1. Set the reference count of the new object to match the
 171          *    reference count of the old object.
 172          * 2. Decrement the reference count of the original object.
 173          */
 174         if (package_index != ACPI_NOT_PACKAGE_ELEMENT) {
 175                 new_object->common.reference_count =
 176                     return_object->common.reference_count;
 177
 178                 if (return_object->common.reference_count > 1) {
 179                         return_object->common.reference_count--;
 180                 }
 181
 182                 ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
 183                                   "%s: Converted %s to expected %s at index %u\n",
 184                                   data->pathname,
 185                                   acpi_ut_get_object_type_name(return_object),
 186                                   acpi_ut_get_object_type_name(new_object),
 187                                   package_index));
 188         } else {
 189                 ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
 190                                   "%s: Converted %s to expected %s\n",
 191                                   data->pathname,
 192                                   acpi_ut_get_object_type_name(return_object),
 193                                   acpi_ut_get_object_type_name(new_object)));
 194         }
 195
 196         /* Delete old object, install the new return object */
 197
 198         acpi_ut_remove_reference(return_object);
 199         *return_object_ptr = new_object;
 200         data->flags |= ACPI_OBJECT_REPAIRED;
 201         return (AE_OK);
 202 }
 203
 204 /*******************************************************************************
 205  *
 206  * FUNCTION:    acpi_ns_convert_to_integer
 207  *
 208  * PARAMETERS:  original_object     - Object to be converted
 209  *              return_object       - Where the new converted object is returned
 210  *
 211  * RETURN:      Status. AE_OK if conversion was successful.
 212  *
 213  * DESCRIPTION: Attempt to convert a String/Buffer object to an Integer.
 214  *
 215  ******************************************************************************/
 216
 217 static acpi_status
 218 acpi_ns_convert_to_integer(union acpi_operand_object *original_object,
 219                            union acpi_operand_object **return_object)
 220 {
 221         union acpi_operand_object *new_object;
 222         acpi_status status;
 223         u64 value = 0;
 224         u32 i;
 225
 226         switch (original_object->common.type) {
 227         case ACPI_TYPE_STRING:
 228
 229                 /* String-to-Integer conversion */
 230
 231                 status = acpi_ut_strtoul64(original_object->string.pointer,
 232                                            ACPI_ANY_BASE, &value);
 233                 if (ACPI_FAILURE(status)) {
 234                         return (status);
 235                 }
 236                 break;
 237
 238         case ACPI_TYPE_BUFFER:
 239
 240                 /* Buffer-to-Integer conversion. Max buffer size is 64 bits. */
 241
 242                 if (original_object->buffer.length > 8) {
 243                         return (AE_AML_OPERAND_TYPE);
 244                 }
 245
 246                 /* Extract each buffer byte to create the integer */
 247
 248                 for (i = 0; i < original_object->buffer.length; i++) {
 249                         value |=
 250                             ((u64) original_object->buffer.
 251                              pointer[i] << (i * 8));
 252                 }
 253                 break;
 254
 255         default:
 256                 return (AE_AML_OPERAND_TYPE);
 257         }
 258
 259         new_object = acpi_ut_create_integer_object(value);
 260         if (!new_object) {
 261                 return (AE_NO_MEMORY);
 262         }
 263
 264         *return_object = new_object;
 265         return (AE_OK);
 266 }
 267
 268 /*******************************************************************************
 269  *
 270  * FUNCTION:    acpi_ns_convert_to_string
 271  *
 272  * PARAMETERS:  original_object     - Object to be converted
 273  *              return_object       - Where the new converted object is returned
 274  *
 275  * RETURN:      Status. AE_OK if conversion was successful.
 276  *
 277  * DESCRIPTION: Attempt to convert a Integer/Buffer object to a String.
 278  *
 279  ******************************************************************************/
 280
 281 static acpi_status
 282 acpi_ns_convert_to_string(union acpi_operand_object *original_object,
 283                           union acpi_operand_object **return_object)
 284 {
 285         union acpi_operand_object *new_object;
 286         acpi_size length;
 287         acpi_status status;
 288
 289         switch (original_object->common.type) {
 290         case ACPI_TYPE_INTEGER:
 291                 /*
 292                  * Integer-to-String conversion. Commonly, convert
 293                  * an integer of value 0 to a NULL string. The last element of
 294                  * _BIF and _BIX packages occasionally need this fix.
 295                  */
 296                 if (original_object->integer.value == 0) {
 297
 298                         /* Allocate a new NULL string object */
 299
 300                         new_object = acpi_ut_create_string_object(0);
 301                         if (!new_object) {
 302                                 return (AE_NO_MEMORY);
 303                         }
 304                 } else {
 305                         status =
 306                             acpi_ex_convert_to_string(original_object,
 307                                                       &new_object,
 308                                                       ACPI_IMPLICIT_CONVERT_HEX);
 309                         if (ACPI_FAILURE(status)) {
 310                                 return (status);
 311                         }
 312                 }
 313                 break;
 314
 315         case ACPI_TYPE_BUFFER:
 316                 /*
 317                  * Buffer-to-String conversion. Use a to_string
 318                  * conversion, no transform performed on the buffer data. The best
 319                  * example of this is the _BIF method, where the string data from
 320                  * the battery is often (incorrectly) returned as buffer object(s).
 321                  */
 322                 length = 0;
 323                 while ((length < original_object->buffer.length) &&
 324                        (original_object->buffer.pointer[length])) {
 325                         length++;
 326                 }
 327
 328                 /* Allocate a new string object */
 329
 330                 new_object = acpi_ut_create_string_object(length);
 331                 if (!new_object) {
 332                         return (AE_NO_MEMORY);
 333                 }
 334
 335                 /*
 336                  * Copy the raw buffer data with no transform. String is already NULL
 337                  * terminated at Length+1.
 338                  */
 339                 ACPI_MEMCPY(new_object->string.pointer,
 340                             original_object->buffer.pointer, length);
 341                 break;
 342
 343         default:
 344                 return (AE_AML_OPERAND_TYPE);
 345         }
 346
 347         *return_object = new_object;
 348         return (AE_OK);
 349 }
 350
 351 /*******************************************************************************
 352  *
 353  * FUNCTION:    acpi_ns_convert_to_buffer
 354  *
 355  * PARAMETERS:  original_object     - Object to be converted
 356  *              return_object       - Where the new converted object is returned
 357  *
 358  * RETURN:      Status. AE_OK if conversion was successful.
 359  *
 360  * DESCRIPTION: Attempt to convert a Integer/String/Package object to a Buffer.
 361  *
 362  ******************************************************************************/
 363
 364 static acpi_status
 365 acpi_ns_convert_to_buffer(union acpi_operand_object *original_object,
 366                           union acpi_operand_object **return_object)
 367 {
 368         union acpi_operand_object *new_object;
 369         acpi_status status;
 370         union acpi_operand_object **elements;
 371         u32 *dword_buffer;
 372         u32 count;
 373         u32 i;
 374
 375         switch (original_object->common.type) {
 376         case ACPI_TYPE_INTEGER:
 377                 /*
 378                  * Integer-to-Buffer conversion.
 379                  * Convert the Integer to a packed-byte buffer. _MAT and other
 380                  * objects need this sometimes, if a read has been performed on a
 381                  * Field object that is less than or equal to the global integer
 382                  * size (32 or 64 bits).
 383                  */
 384                 status =
 385                     acpi_ex_convert_to_buffer(original_object, &new_object);
 386                 if (ACPI_FAILURE(status)) {
 387                         return (status);
 388                 }
 389                 break;
 390
 391         case ACPI_TYPE_STRING:
 392
 393                 /* String-to-Buffer conversion. Simple data copy */
 394
 395                 new_object =
 396                     acpi_ut_create_buffer_object(original_object->string.
 397                                                  length);
 398                 if (!new_object) {
 399                         return (AE_NO_MEMORY);
 400                 }
 401
 402                 ACPI_MEMCPY(new_object->buffer.pointer,
 403                             original_object->string.pointer,
 404                             original_object->string.length);
 405                 break;
 406
 407         case ACPI_TYPE_PACKAGE:
 408                 /*
 409                  * This case is often seen for predefined names that must return a
 410                  * Buffer object with multiple DWORD integers within. For example,
 411                  * _FDE and _GTM. The Package can be converted to a Buffer.
 412                  */
 413
 414                 /* All elements of the Package must be integers */
 415
 416                 elements = original_object->package.elements;
 417                 count = original_object->package.count;
 418
 419                 for (i = 0; i < count; i++) {
 420                         if ((!*elements) ||
 421                             ((*elements)->common.type != ACPI_TYPE_INTEGER)) {
 422                                 return (AE_AML_OPERAND_TYPE);
 423                         }
 424                         elements++;
 425                 }
 426
 427                 /* Create the new buffer object to replace the Package */
 428
 429                 new_object = acpi_ut_create_buffer_object(ACPI_MUL_4(count));
 430                 if (!new_object) {
 431                         return (AE_NO_MEMORY);
 432                 }
 433
 434                 /* Copy the package elements (integers) to the buffer as DWORDs */
 435
 436                 elements = original_object->package.elements;
 437                 dword_buffer = ACPI_CAST_PTR(u32, new_object->buffer.pointer);
 438
 439                 for (i = 0; i < count; i++) {
 440                         *dword_buffer = (u32) (*elements)->integer.value;
 441                         dword_buffer++;
 442                         elements++;
 443                 }
 444                 break;
 445
 446         default:
 447                 return (AE_AML_OPERAND_TYPE);
 448         }
 449
 450         *return_object = new_object;
 451         return (AE_OK);
 452 }
 453
 454 /*******************************************************************************
 455  *
 456  * FUNCTION:    acpi_ns_convert_to_package
 457  *
 458  * PARAMETERS:  original_object     - Object to be converted
 459  *              return_object       - Where the new converted object is returned
 460  *
 461  * RETURN:      Status. AE_OK if conversion was successful.
 462  *
 463  * DESCRIPTION: Attempt to convert a Buffer object to a Package. Each byte of
 464  *              the buffer is converted to a single integer package element.
 465  *
 466  ******************************************************************************/
 467
 468 static acpi_status
 469 acpi_ns_convert_to_package(union acpi_operand_object *original_object,
 470                            union acpi_operand_object **return_object)
 471 {
 472         union acpi_operand_object *new_object;
 473         union acpi_operand_object **elements;
 474         u32 length;
 475         u8 *buffer;
 476
 477         switch (original_object->common.type) {
 478         case ACPI_TYPE_BUFFER:
 479
 480                 /* Buffer-to-Package conversion */
 481
 482                 length = original_object->buffer.length;
 483                 new_object = acpi_ut_create_package_object(length);
 484                 if (!new_object) {
 485                         return (AE_NO_MEMORY);
 486                 }
 487
 488                 /* Convert each buffer byte to an integer package element */
 489
 490                 elements = new_object->package.elements;
 491                 buffer = original_object->buffer.pointer;
 492
 493                 while (length--) {
 494                         *elements =
 495                             acpi_ut_create_integer_object((u64) *buffer);
 496                         if (!*elements) {
 497                                 acpi_ut_remove_reference(new_object);
 498                                 return (AE_NO_MEMORY);
 499                         }
 500                         elements++;
 501                         buffer++;
 502                 }
 503                 break;
 504
 505         default:
 506                 return (AE_AML_OPERAND_TYPE);
 507         }
 508
 509         *return_object = new_object;
 510         return (AE_OK);
 511 }
 512
 513 /*******************************************************************************
 514  *
 515  * FUNCTION:    acpi_ns_repair_null_element
 516  *
 517  * PARAMETERS:  Data                - Pointer to validation data structure
 518  *              expected_btypes     - Object types expected
 519  *              package_index       - Index of object within parent package (if
 520  *                                    applicable - ACPI_NOT_PACKAGE_ELEMENT
 521  *                                    otherwise)
 522  *              return_object_ptr   - Pointer to the object returned from the
 523  *                                    evaluation of a method or object
 524  *
 525  * RETURN:      Status. AE_OK if repair was successful.
 526  *
 527  * DESCRIPTION: Attempt to repair a NULL element of a returned Package object.
 528  *
 529  ******************************************************************************/
 530
 531 acpi_status
 532 acpi_ns_repair_null_element(struct acpi_predefined_data *data,
 533                             u32 expected_btypes,
 534                             u32 package_index,
 535                             union acpi_operand_object **return_object_ptr)
 536 {
 537         union acpi_operand_object *return_object = *return_object_ptr;
 538         union acpi_operand_object *new_object;
 539
 540         ACPI_FUNCTION_NAME(ns_repair_null_element);
 541
 542         /* No repair needed if return object is non-NULL */
 543
 544         if (return_object) {
 545                 return (AE_OK);
 546         }
 547
 548         /*
 549          * Attempt to repair a NULL element of a Package object. This applies to
 550          * predefined names that return a fixed-length package and each element
 551          * is required. It does not apply to variable-length packages where NULL
 552          * elements are allowed, especially at the end of the package.
 553          */
 554         if (expected_btypes & ACPI_RTYPE_INTEGER) {
 555
 556                 /* Need an Integer - create a zero-value integer */
 557
 558                 new_object = acpi_ut_create_integer_object((u64)0);
 559         } else if (expected_btypes & ACPI_RTYPE_STRING) {
 560
 561                 /* Need a String - create a NULL string */
 562
 563                 new_object = acpi_ut_create_string_object(0);
 564         } else if (expected_btypes & ACPI_RTYPE_BUFFER) {
 565
 566                 /* Need a Buffer - create a zero-length buffer */
 567
 568                 new_object = acpi_ut_create_buffer_object(0);
 569         } else {
 570                 /* Error for all other expected types */
 571
 572                 return (AE_AML_OPERAND_TYPE);
 573         }
 574
 575         if (!new_object) {
 576                 return (AE_NO_MEMORY);
 577         }
 578
 579         /* Set the reference count according to the parent Package object */
 580
 581         new_object->common.reference_count =
 582             data->parent_package->common.reference_count;
 583
 584         ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
 585                           "%s: Converted NULL package element to expected %s at index %u\n",
 586                           data->pathname,
 587                           acpi_ut_get_object_type_name(new_object),
 588                           package_index));
 589
 590         *return_object_ptr = new_object;
 591         data->flags |= ACPI_OBJECT_REPAIRED;
 592         return (AE_OK);
 593 }
 594
 595 /******************************************************************************
 596  *
 597  * FUNCTION:    acpi_ns_remove_null_elements
 598  *
 599  * PARAMETERS:  Data                - Pointer to validation data structure
 600  *              package_type        - An acpi_return_package_types value
 601  *              obj_desc            - A Package object
 602  *
 603  * RETURN:      None.
 604  *
 605  * DESCRIPTION: Remove all NULL package elements from packages that contain
 606  *              a variable number of sub-packages. For these types of
 607  *              packages, NULL elements can be safely removed.
 608  *
 609  *****************************************************************************/
 610
 611 void
 612 acpi_ns_remove_null_elements(struct acpi_predefined_data *data,
 613                              u8 package_type,
 614                              union acpi_operand_object *obj_desc)
 615 {
 616         union acpi_operand_object **source;
 617         union acpi_operand_object **dest;
 618         u32 count;
 619         u32 new_count;
 620         u32 i;
 621
 622         ACPI_FUNCTION_NAME(ns_remove_null_elements);
 623
 624         /*
 625          * We can safely remove all NULL elements from these package types:
 626          * PTYPE1_VAR packages contain a variable number of simple data types.
 627          * PTYPE2 packages contain a variable number of sub-packages.
 628          */
 629         switch (package_type) {
 630         case ACPI_PTYPE1_VAR:
 631         case ACPI_PTYPE2:
 632         case ACPI_PTYPE2_COUNT:
 633         case ACPI_PTYPE2_PKG_COUNT:
 634         case ACPI_PTYPE2_FIXED:
 635         case ACPI_PTYPE2_MIN:
 636         case ACPI_PTYPE2_REV_FIXED:
 637                 break;
 638
 639         default:
 640         case ACPI_PTYPE1_FIXED:
 641         case ACPI_PTYPE1_OPTION:
 642                 return;
 643         }
 644
 645         count = obj_desc->package.count;
 646         new_count = count;
 647
 648         source = obj_desc->package.elements;
 649         dest = source;
 650
 651         /* Examine all elements of the package object, remove nulls */
 652
 653         for (i = 0; i < count; i++) {
 654                 if (!*source) {
 655                         new_count--;
 656                 } else {
 657                         *dest = *source;
 658                         dest++;
 659                 }
 660                 source++;
 661         }
 662
 663         /* Update parent package if any null elements were removed */
 664
 665         if (new_count < count) {
 666                 ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
 667                                   "%s: Found and removed %u NULL elements\n",
 668                                   data->pathname, (count - new_count)));
 669
 670                 /* NULL terminate list and update the package count */
 671
 672                 *dest = NULL;
 673                 obj_desc->package.count = new_count;
 674         }
 675 }
 676
 677 /*******************************************************************************
 678  *
 679  * FUNCTION:    acpi_ns_repair_package_list
 680  *
 681  * PARAMETERS:  Data                - Pointer to validation data structure
 682  *              obj_desc_ptr        - Pointer to the object to repair. The new
 683  *                                    package object is returned here,
 684  *                                    overwriting the old object.
 685  *
 686  * RETURN:      Status, new object in *obj_desc_ptr
 687  *
 688  * DESCRIPTION: Repair a common problem with objects that are defined to return
 689  *              a variable-length Package of Packages. If the variable-length
 690  *              is one, some BIOS code mistakenly simply declares a single
 691  *              Package instead of a Package with one sub-Package. This
 692  *              function attempts to repair this error by wrapping a Package
 693  *              object around the original Package, creating the correct
 694  *              Package with one sub-Package.
 695  *
 696  *              Names that can be repaired in this manner include:
 697  *              _ALR, _CSD, _HPX, _MLS, _PRT, _PSS, _TRT, TSS
 698  *
 699  ******************************************************************************/
 700
 701 acpi_status
 702 acpi_ns_repair_package_list(struct acpi_predefined_data *data,
 703                             union acpi_operand_object **obj_desc_ptr)
 704 {
 705         union acpi_operand_object *pkg_obj_desc;
 706
 707         ACPI_FUNCTION_NAME(ns_repair_package_list);
 708
 709         /*
 710          * Create the new outer package and populate it. The new package will
 711          * have a single element, the lone subpackage.
 712          */
 713         pkg_obj_desc = acpi_ut_create_package_object(1);
 714         if (!pkg_obj_desc) {
 715                 return (AE_NO_MEMORY);
 716         }
 717
 718         pkg_obj_desc->package.elements[0] = *obj_desc_ptr;
 719
 720         /* Return the new object in the object pointer */
 721
 722         *obj_desc_ptr = pkg_obj_desc;
 723         data->flags |= ACPI_OBJECT_REPAIRED;
 724
 725         ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
 726                           "%s: Repaired incorrectly formed Package\n",
 727                           data->pathname));
 728
 729         return (AE_OK);
 730 }