git.oblomov.eu Git - linux-2.6/blob - drivers/acpi/executer/exconvrt.c

   1 /******************************************************************************
   2  *
   3  * Module Name: exconvrt - Object conversion routines
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2006, R. Byron Moore
   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 <acpi/acinterp.h>
  46 #include <acpi/amlcode.h>
  47
  48 #define _COMPONENT          ACPI_EXECUTER
  49 ACPI_MODULE_NAME("exconvrt")
  50
  51 /* Local prototypes */
  52 static u32
  53 acpi_ex_convert_to_ascii(acpi_integer integer,
  54                          u16 base, u8 * string, u8 max_length);
  55
  56 /*******************************************************************************
  57  *
  58  * FUNCTION:    acpi_ex_convert_to_integer
  59  *
  60  * PARAMETERS:  obj_desc        - Object to be converted.  Must be an
  61  *                                Integer, Buffer, or String
  62  *              result_desc     - Where the new Integer object is returned
  63  *              Flags           - Used for string conversion
  64  *
  65  * RETURN:      Status
  66  *
  67  * DESCRIPTION: Convert an ACPI Object to an integer.
  68  *
  69  ******************************************************************************/
  70
  71 acpi_status
  72 acpi_ex_convert_to_integer(union acpi_operand_object *obj_desc,
  73                            union acpi_operand_object **result_desc, u32 flags)
  74 {
  75         union acpi_operand_object *return_desc;
  76         u8 *pointer;
  77         acpi_integer result;
  78         u32 i;
  79         u32 count;
  80         acpi_status status;
  81
  82         ACPI_FUNCTION_TRACE_PTR("ex_convert_to_integer", obj_desc);
  83
  84         switch (ACPI_GET_OBJECT_TYPE(obj_desc)) {
  85         case ACPI_TYPE_INTEGER:
  86
  87                 /* No conversion necessary */
  88
  89                 *result_desc = obj_desc;
  90                 return_ACPI_STATUS(AE_OK);
  91
  92         case ACPI_TYPE_BUFFER:
  93         case ACPI_TYPE_STRING:
  94
  95                 /* Note: Takes advantage of common buffer/string fields */
  96
  97                 pointer = obj_desc->buffer.pointer;
  98                 count = obj_desc->buffer.length;
  99                 break;
 100
 101         default:
 102                 return_ACPI_STATUS(AE_TYPE);
 103         }
 104
 105         /*
 106          * Convert the buffer/string to an integer.  Note that both buffers and
 107          * strings are treated as raw data - we don't convert ascii to hex for
 108          * strings.
 109          *
 110          * There are two terminating conditions for the loop:
 111          * 1) The size of an integer has been reached, or
 112          * 2) The end of the buffer or string has been reached
 113          */
 114         result = 0;
 115
 116         /* String conversion is different than Buffer conversion */
 117
 118         switch (ACPI_GET_OBJECT_TYPE(obj_desc)) {
 119         case ACPI_TYPE_STRING:
 120
 121                 /*
 122                  * Convert string to an integer - for most cases, the string must be
 123                  * hexadecimal as per the ACPI specification.  The only exception (as
 124                  * of ACPI 3.0) is that the to_integer() operator allows both decimal
 125                  * and hexadecimal strings (hex prefixed with "0x").
 126                  */
 127                 status = acpi_ut_strtoul64((char *)pointer, flags, &result);
 128                 if (ACPI_FAILURE(status)) {
 129                         return_ACPI_STATUS(status);
 130                 }
 131                 break;
 132
 133         case ACPI_TYPE_BUFFER:
 134
 135                 /* Check for zero-length buffer */
 136
 137                 if (!count) {
 138                         return_ACPI_STATUS(AE_AML_BUFFER_LIMIT);
 139                 }
 140
 141                 /* Transfer no more than an integer's worth of data */
 142
 143                 if (count > acpi_gbl_integer_byte_width) {
 144                         count = acpi_gbl_integer_byte_width;
 145                 }
 146
 147                 /*
 148                  * Convert buffer to an integer - we simply grab enough raw data
 149                  * from the buffer to fill an integer
 150                  */
 151                 for (i = 0; i < count; i++) {
 152                         /*
 153                          * Get next byte and shift it into the Result.
 154                          * Little endian is used, meaning that the first byte of the buffer
 155                          * is the LSB of the integer
 156                          */
 157                         result |= (((acpi_integer) pointer[i]) << (i * 8));
 158                 }
 159                 break;
 160
 161         default:
 162                 /* No other types can get here */
 163                 break;
 164         }
 165
 166         /* Create a new integer */
 167
 168         return_desc = acpi_ut_create_internal_object(ACPI_TYPE_INTEGER);
 169         if (!return_desc) {
 170                 return_ACPI_STATUS(AE_NO_MEMORY);
 171         }
 172
 173         /* Save the Result */
 174
 175         return_desc->integer.value = result;
 176         acpi_ex_truncate_for32bit_table(return_desc);
 177         *result_desc = return_desc;
 178         return_ACPI_STATUS(AE_OK);
 179 }
 180
 181 /*******************************************************************************
 182  *
 183  * FUNCTION:    acpi_ex_convert_to_buffer
 184  *
 185  * PARAMETERS:  obj_desc        - Object to be converted.  Must be an
 186  *                                Integer, Buffer, or String
 187  *              result_desc     - Where the new buffer object is returned
 188  *
 189  * RETURN:      Status
 190  *
 191  * DESCRIPTION: Convert an ACPI Object to a Buffer
 192  *
 193  ******************************************************************************/
 194
 195 acpi_status
 196 acpi_ex_convert_to_buffer(union acpi_operand_object *obj_desc,
 197                           union acpi_operand_object **result_desc)
 198 {
 199         union acpi_operand_object *return_desc;
 200         u8 *new_buf;
 201
 202         ACPI_FUNCTION_TRACE_PTR("ex_convert_to_buffer", obj_desc);
 203
 204         switch (ACPI_GET_OBJECT_TYPE(obj_desc)) {
 205         case ACPI_TYPE_BUFFER:
 206
 207                 /* No conversion necessary */
 208
 209                 *result_desc = obj_desc;
 210                 return_ACPI_STATUS(AE_OK);
 211
 212         case ACPI_TYPE_INTEGER:
 213
 214                 /*
 215                  * Create a new Buffer object.
 216                  * Need enough space for one integer
 217                  */
 218                 return_desc =
 219                     acpi_ut_create_buffer_object(acpi_gbl_integer_byte_width);
 220                 if (!return_desc) {
 221                         return_ACPI_STATUS(AE_NO_MEMORY);
 222                 }
 223
 224                 /* Copy the integer to the buffer, LSB first */
 225
 226                 new_buf = return_desc->buffer.pointer;
 227                 ACPI_MEMCPY(new_buf,
 228                             &obj_desc->integer.value,
 229                             acpi_gbl_integer_byte_width);
 230                 break;
 231
 232         case ACPI_TYPE_STRING:
 233
 234                 /*
 235                  * Create a new Buffer object
 236                  * Size will be the string length
 237                  *
 238                  * NOTE: Add one to the string length to include the null terminator.
 239                  * The ACPI spec is unclear on this subject, but there is existing
 240                  * ASL/AML code that depends on the null being transferred to the new
 241                  * buffer.
 242                  */
 243                 return_desc = acpi_ut_create_buffer_object((acpi_size)
 244                                                            obj_desc->string.
 245                                                            length + 1);
 246                 if (!return_desc) {
 247                         return_ACPI_STATUS(AE_NO_MEMORY);
 248                 }
 249
 250                 /* Copy the string to the buffer */
 251
 252                 new_buf = return_desc->buffer.pointer;
 253                 ACPI_STRNCPY((char *)new_buf, (char *)obj_desc->string.pointer,
 254                              obj_desc->string.length);
 255                 break;
 256
 257         default:
 258                 return_ACPI_STATUS(AE_TYPE);
 259         }
 260
 261         /* Mark buffer initialized */
 262
 263         return_desc->common.flags |= AOPOBJ_DATA_VALID;
 264         *result_desc = return_desc;
 265         return_ACPI_STATUS(AE_OK);
 266 }
 267
 268 /*******************************************************************************
 269  *
 270  * FUNCTION:    acpi_ex_convert_to_ascii
 271  *
 272  * PARAMETERS:  Integer         - Value to be converted
 273  *              Base            - ACPI_STRING_DECIMAL or ACPI_STRING_HEX
 274  *              String          - Where the string is returned
 275  *              data_width      - Size of data item to be converted, in bytes
 276  *
 277  * RETURN:      Actual string length
 278  *
 279  * DESCRIPTION: Convert an ACPI Integer to a hex or decimal string
 280  *
 281  ******************************************************************************/
 282
 283 static u32
 284 acpi_ex_convert_to_ascii(acpi_integer integer,
 285                          u16 base, u8 * string, u8 data_width)
 286 {
 287         acpi_integer digit;
 288         acpi_native_uint i;
 289         acpi_native_uint j;
 290         acpi_native_uint k = 0;
 291         acpi_native_uint hex_length;
 292         acpi_native_uint decimal_length;
 293         u32 remainder;
 294         u8 supress_zeros;
 295
 296         ACPI_FUNCTION_ENTRY();
 297
 298         switch (base) {
 299         case 10:
 300
 301                 /* Setup max length for the decimal number */
 302
 303                 switch (data_width) {
 304                 case 1:
 305                         decimal_length = ACPI_MAX8_DECIMAL_DIGITS;
 306                         break;
 307
 308                 case 4:
 309                         decimal_length = ACPI_MAX32_DECIMAL_DIGITS;
 310                         break;
 311
 312                 case 8:
 313                 default:
 314                         decimal_length = ACPI_MAX64_DECIMAL_DIGITS;
 315                         break;
 316                 }
 317
 318                 supress_zeros = TRUE;   /* No leading zeros */
 319                 remainder = 0;
 320
 321                 for (i = decimal_length; i > 0; i--) {
 322                         /* Divide by nth factor of 10 */
 323
 324                         digit = integer;
 325                         for (j = 0; j < i; j++) {
 326                                 (void)acpi_ut_short_divide(digit, 10, &digit,
 327                                                            &remainder);
 328                         }
 329
 330                         /* Handle leading zeros */
 331
 332                         if (remainder != 0) {
 333                                 supress_zeros = FALSE;
 334                         }
 335
 336                         if (!supress_zeros) {
 337                                 string[k] = (u8) (ACPI_ASCII_ZERO + remainder);
 338                                 k++;
 339                         }
 340                 }
 341                 break;
 342
 343         case 16:
 344
 345                 /* hex_length: 2 ascii hex chars per data byte */
 346
 347                 hex_length = (acpi_native_uint) ACPI_MUL_2(data_width);
 348                 for (i = 0, j = (hex_length - 1); i < hex_length; i++, j--) {
 349                         /* Get one hex digit, most significant digits first */
 350
 351                         string[k] =
 352                             (u8) acpi_ut_hex_to_ascii_char(integer,
 353                                                            ACPI_MUL_4(j));
 354                         k++;
 355                 }
 356                 break;
 357
 358         default:
 359                 return (0);
 360         }
 361
 362         /*
 363          * Since leading zeros are supressed, we must check for the case where
 364          * the integer equals 0
 365          *
 366          * Finally, null terminate the string and return the length
 367          */
 368         if (!k) {
 369                 string[0] = ACPI_ASCII_ZERO;
 370                 k = 1;
 371         }
 372
 373         string[k] = 0;
 374         return ((u32) k);
 375 }
 376
 377 /*******************************************************************************
 378  *
 379  * FUNCTION:    acpi_ex_convert_to_string
 380  *
 381  * PARAMETERS:  obj_desc        - Object to be converted.  Must be an
 382  *                                Integer, Buffer, or String
 383  *              result_desc     - Where the string object is returned
 384  *              Type            - String flags (base and conversion type)
 385  *
 386  * RETURN:      Status
 387  *
 388  * DESCRIPTION: Convert an ACPI Object to a string
 389  *
 390  ******************************************************************************/
 391
 392 acpi_status
 393 acpi_ex_convert_to_string(union acpi_operand_object * obj_desc,
 394                           union acpi_operand_object ** result_desc, u32 type)
 395 {
 396         union acpi_operand_object *return_desc;
 397         u8 *new_buf;
 398         u32 i;
 399         u32 string_length = 0;
 400         u16 base = 16;
 401         u8 separator = ',';
 402
 403         ACPI_FUNCTION_TRACE_PTR("ex_convert_to_string", obj_desc);
 404
 405         switch (ACPI_GET_OBJECT_TYPE(obj_desc)) {
 406         case ACPI_TYPE_STRING:
 407
 408                 /* No conversion necessary */
 409
 410                 *result_desc = obj_desc;
 411                 return_ACPI_STATUS(AE_OK);
 412
 413         case ACPI_TYPE_INTEGER:
 414
 415                 switch (type) {
 416                 case ACPI_EXPLICIT_CONVERT_DECIMAL:
 417
 418                         /* Make room for maximum decimal number */
 419
 420                         string_length = ACPI_MAX_DECIMAL_DIGITS;
 421                         base = 10;
 422                         break;
 423
 424                 default:
 425
 426                         /* Two hex string characters for each integer byte */
 427
 428                         string_length = ACPI_MUL_2(acpi_gbl_integer_byte_width);
 429                         break;
 430                 }
 431
 432                 /*
 433                  * Create a new String
 434                  * Need enough space for one ASCII integer (plus null terminator)
 435                  */
 436                 return_desc =
 437                     acpi_ut_create_string_object((acpi_size) string_length);
 438                 if (!return_desc) {
 439                         return_ACPI_STATUS(AE_NO_MEMORY);
 440                 }
 441
 442                 new_buf = return_desc->buffer.pointer;
 443
 444                 /* Convert integer to string */
 445
 446                 string_length =
 447                     acpi_ex_convert_to_ascii(obj_desc->integer.value, base,
 448                                              new_buf,
 449                                              acpi_gbl_integer_byte_width);
 450
 451                 /* Null terminate at the correct place */
 452
 453                 return_desc->string.length = string_length;
 454                 new_buf[string_length] = 0;
 455                 break;
 456
 457         case ACPI_TYPE_BUFFER:
 458
 459                 /* Setup string length, base, and separator */
 460
 461                 switch (type) {
 462                 case ACPI_EXPLICIT_CONVERT_DECIMAL:     /* Used by to_decimal_string */
 463                         /*
 464                          * From ACPI: "If Data is a buffer, it is converted to a string of
 465                          * decimal values separated by commas."
 466                          */
 467                         base = 10;
 468
 469                         /*
 470                          * Calculate the final string length.  Individual string values
 471                          * are variable length (include separator for each)
 472                          */
 473                         for (i = 0; i < obj_desc->buffer.length; i++) {
 474                                 if (obj_desc->buffer.pointer[i] >= 100) {
 475                                         string_length += 4;
 476                                 } else if (obj_desc->buffer.pointer[i] >= 10) {
 477                                         string_length += 3;
 478                                 } else {
 479                                         string_length += 2;
 480                                 }
 481                         }
 482                         break;
 483
 484                 case ACPI_IMPLICIT_CONVERT_HEX:
 485                         /*
 486                          * From the ACPI spec:
 487                          *"The entire contents of the buffer are converted to a string of
 488                          * two-character hexadecimal numbers, each separated by a space."
 489                          */
 490                         separator = ' ';
 491                         string_length = (obj_desc->buffer.length * 3);
 492                         break;
 493
 494                 case ACPI_EXPLICIT_CONVERT_HEX: /* Used by to_hex_string */
 495                         /*
 496                          * From ACPI: "If Data is a buffer, it is converted to a string of
 497                          * hexadecimal values separated by commas."
 498                          */
 499                         string_length = (obj_desc->buffer.length * 3);
 500                         break;
 501
 502                 default:
 503                         return_ACPI_STATUS(AE_BAD_PARAMETER);
 504                 }
 505
 506                 /*
 507                  * Create a new string object and string buffer
 508                  * (-1 because of extra separator included in string_length from above)
 509                  */
 510                 return_desc =
 511                     acpi_ut_create_string_object((acpi_size)
 512                                                  (string_length - 1));
 513                 if (!return_desc) {
 514                         return_ACPI_STATUS(AE_NO_MEMORY);
 515                 }
 516
 517                 new_buf = return_desc->buffer.pointer;
 518
 519                 /*
 520                  * Convert buffer bytes to hex or decimal values
 521                  * (separated by commas or spaces)
 522                  */
 523                 for (i = 0; i < obj_desc->buffer.length; i++) {
 524                         new_buf += acpi_ex_convert_to_ascii((acpi_integer)
 525                                                             obj_desc->buffer.
 526                                                             pointer[i], base,
 527                                                             new_buf, 1);
 528                         *new_buf++ = separator; /* each separated by a comma or space */
 529                 }
 530
 531                 /*
 532                  * Null terminate the string
 533                  * (overwrites final comma/space from above)
 534                  */
 535                 new_buf--;
 536                 *new_buf = 0;
 537                 break;
 538
 539         default:
 540                 return_ACPI_STATUS(AE_TYPE);
 541         }
 542
 543         *result_desc = return_desc;
 544         return_ACPI_STATUS(AE_OK);
 545 }
 546
 547 /*******************************************************************************
 548  *
 549  * FUNCTION:    acpi_ex_convert_to_target_type
 550  *
 551  * PARAMETERS:  destination_type    - Current type of the destination
 552  *              source_desc         - Source object to be converted.
 553  *              result_desc         - Where the converted object is returned
 554  *              walk_state          - Current method state
 555  *
 556  * RETURN:      Status
 557  *
 558  * DESCRIPTION: Implements "implicit conversion" rules for storing an object.
 559  *
 560  ******************************************************************************/
 561
 562 acpi_status
 563 acpi_ex_convert_to_target_type(acpi_object_type destination_type,
 564                                union acpi_operand_object *source_desc,
 565                                union acpi_operand_object **result_desc,
 566                                struct acpi_walk_state *walk_state)
 567 {
 568         acpi_status status = AE_OK;
 569
 570         ACPI_FUNCTION_TRACE("ex_convert_to_target_type");
 571
 572         /* Default behavior */
 573
 574         *result_desc = source_desc;
 575
 576         /*
 577          * If required by the target,
 578          * perform implicit conversion on the source before we store it.
 579          */
 580         switch (GET_CURRENT_ARG_TYPE(walk_state->op_info->runtime_args)) {
 581         case ARGI_SIMPLE_TARGET:
 582         case ARGI_FIXED_TARGET:
 583         case ARGI_INTEGER_REF:  /* Handles Increment, Decrement cases */
 584
 585                 switch (destination_type) {
 586                 case ACPI_TYPE_LOCAL_REGION_FIELD:
 587                         /*
 588                          * Named field can always handle conversions
 589                          */
 590                         break;
 591
 592                 default:
 593                         /* No conversion allowed for these types */
 594
 595                         if (destination_type !=
 596                             ACPI_GET_OBJECT_TYPE(source_desc)) {
 597                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 598                                                   "Explicit operator, will store (%s) over existing type (%s)\n",
 599                                                   acpi_ut_get_object_type_name
 600                                                   (source_desc),
 601                                                   acpi_ut_get_type_name
 602                                                   (destination_type)));
 603                                 status = AE_TYPE;
 604                         }
 605                 }
 606                 break;
 607
 608         case ARGI_TARGETREF:
 609
 610                 switch (destination_type) {
 611                 case ACPI_TYPE_INTEGER:
 612                 case ACPI_TYPE_BUFFER_FIELD:
 613                 case ACPI_TYPE_LOCAL_BANK_FIELD:
 614                 case ACPI_TYPE_LOCAL_INDEX_FIELD:
 615                         /*
 616                          * These types require an Integer operand.  We can convert
 617                          * a Buffer or a String to an Integer if necessary.
 618                          */
 619                         status =
 620                             acpi_ex_convert_to_integer(source_desc, result_desc,
 621                                                        16);
 622                         break;
 623
 624                 case ACPI_TYPE_STRING:
 625                         /*
 626                          * The operand must be a String.  We can convert an
 627                          * Integer or Buffer if necessary
 628                          */
 629                         status =
 630                             acpi_ex_convert_to_string(source_desc, result_desc,
 631                                                       ACPI_IMPLICIT_CONVERT_HEX);
 632                         break;
 633
 634                 case ACPI_TYPE_BUFFER:
 635                         /*
 636                          * The operand must be a Buffer.  We can convert an
 637                          * Integer or String if necessary
 638                          */
 639                         status =
 640                             acpi_ex_convert_to_buffer(source_desc, result_desc);
 641                         break;
 642
 643                 default:
 644                         ACPI_ERROR((AE_INFO,
 645                                     "Bad destination type during conversion: %X",
 646                                     destination_type));
 647                         status = AE_AML_INTERNAL;
 648                         break;
 649                 }
 650                 break;
 651
 652         case ARGI_REFERENCE:
 653                 /*
 654                  * create_xxxx_field cases - we are storing the field object into the name
 655                  */
 656                 break;
 657
 658         default:
 659                 ACPI_ERROR((AE_INFO,
 660                             "Unknown Target type ID 0x%X aml_opcode %X dest_type %s",
 661                             GET_CURRENT_ARG_TYPE(walk_state->op_info->
 662                                                  runtime_args),
 663                             walk_state->opcode,
 664                             acpi_ut_get_type_name(destination_type)));
 665                 status = AE_AML_INTERNAL;
 666         }
 667
 668         /*
 669          * Source-to-Target conversion semantics:
 670          *
 671          * If conversion to the target type cannot be performed, then simply
 672          * overwrite the target with the new object and type.
 673          */
 674         if (status == AE_TYPE) {
 675                 status = AE_OK;
 676         }
 677
 678         return_ACPI_STATUS(status);
 679 }