drivers/acpi/tables/tbxface.c

   1 /******************************************************************************
   2  *
   3  * Module Name: tbxface - Public interfaces to the ACPI subsystem
   4  *                         ACPI table oriented interfaces
   5  *
   6  *****************************************************************************/
   7
   8 /*
   9  * Copyright (C) 2000 - 2008, Intel Corp.
  10  * All rights reserved.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions, and the following disclaimer,
  17  *    without modification.
  18  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  19  *    substantially similar to the "NO WARRANTY" disclaimer below
  20  *    ("Disclaimer") and any redistribution must be conditioned upon
  21  *    including a substantially similar Disclaimer requirement for further
  22  *    binary redistribution.
  23  * 3. Neither the names of the above-listed copyright holders nor the names
  24  *    of any contributors may be used to endorse or promote products derived
  25  *    from this software without specific prior written permission.
  26  *
  27  * Alternatively, this software may be distributed under the terms of the
  28  * GNU General Public License ("GPL") version 2 as published by the Free
  29  * Software Foundation.
  30  *
  31  * NO WARRANTY
  32  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  33  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  34  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  35  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  36  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  40  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  41  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  42  * POSSIBILITY OF SUCH DAMAGES.
  43  */
  44
  45 #include <acpi/acpi.h>
  46 #include <acpi/acnamesp.h>
  47 #include <acpi/actables.h>
  48
  49 #define _COMPONENT          ACPI_TABLES
  50 ACPI_MODULE_NAME("tbxface")
  51
  52 /* Local prototypes */
  53 static acpi_status acpi_tb_load_namespace(void);
  54
  55 static int no_auto_ssdt;
  56
  57 /*******************************************************************************
  58  *
  59  * FUNCTION:    acpi_allocate_root_table
  60  *
  61  * PARAMETERS:  initial_table_count - Size of initial_table_array, in number of
  62  *                                    struct acpi_table_desc structures
  63  *
  64  * RETURN:      Status
  65  *
  66  * DESCRIPTION: Allocate a root table array. Used by i_aSL compiler and
  67  *              acpi_initialize_tables.
  68  *
  69  ******************************************************************************/
  70
  71 acpi_status acpi_allocate_root_table(u32 initial_table_count)
  72 {
  73
  74         acpi_gbl_root_table_list.size = initial_table_count;
  75         acpi_gbl_root_table_list.flags = ACPI_ROOT_ALLOW_RESIZE;
  76
  77         return (acpi_tb_resize_root_table_list());
  78 }
  79
  80 /*******************************************************************************
  81  *
  82  * FUNCTION:    acpi_initialize_tables
  83  *
  84  * PARAMETERS:  initial_table_array - Pointer to an array of pre-allocated
  85  *                                    struct acpi_table_desc structures. If NULL, the
  86  *                                    array is dynamically allocated.
  87  *              initial_table_count - Size of initial_table_array, in number of
  88  *                                    struct acpi_table_desc structures
  89  *              allow_realloc       - Flag to tell Table Manager if resize of
  90  *                                    pre-allocated array is allowed. Ignored
  91  *                                    if initial_table_array is NULL.
  92  *
  93  * RETURN:      Status
  94  *
  95  * DESCRIPTION: Initialize the table manager, get the RSDP and RSDT/XSDT.
  96  *
  97  * NOTE:        Allows static allocation of the initial table array in order
  98  *              to avoid the use of dynamic memory in confined environments
  99  *              such as the kernel boot sequence where it may not be available.
 100  *
 101  *              If the host OS memory managers are initialized, use NULL for
 102  *              initial_table_array, and the table will be dynamically allocated.
 103  *
 104  ******************************************************************************/
 105
 106 acpi_status __init
 107 acpi_initialize_tables(struct acpi_table_desc * initial_table_array,
 108                        u32 initial_table_count, u8 allow_resize)
 109 {
 110         acpi_physical_address rsdp_address;
 111         acpi_status status;
 112
 113         ACPI_FUNCTION_TRACE(acpi_initialize_tables);
 114
 115         /*
 116          * Set up the Root Table Array
 117          * Allocate the table array if requested
 118          */
 119         if (!initial_table_array) {
 120                 status = acpi_allocate_root_table(initial_table_count);
 121                 if (ACPI_FAILURE(status)) {
 122                         return_ACPI_STATUS(status);
 123                 }
 124         } else {
 125                 /* Root Table Array has been statically allocated by the host */
 126
 127                 ACPI_MEMSET(initial_table_array, 0,
 128                             (acpi_size) initial_table_count *
 129                             sizeof(struct acpi_table_desc));
 130
 131                 acpi_gbl_root_table_list.tables = initial_table_array;
 132                 acpi_gbl_root_table_list.size = initial_table_count;
 133                 acpi_gbl_root_table_list.flags = ACPI_ROOT_ORIGIN_UNKNOWN;
 134                 if (allow_resize) {
 135                         acpi_gbl_root_table_list.flags |=
 136                             ACPI_ROOT_ALLOW_RESIZE;
 137                 }
 138         }
 139
 140         /* Get the address of the RSDP */
 141
 142         rsdp_address = acpi_os_get_root_pointer();
 143         if (!rsdp_address) {
 144                 return_ACPI_STATUS(AE_NOT_FOUND);
 145         }
 146
 147         /*
 148          * Get the root table (RSDT or XSDT) and extract all entries to the local
 149          * Root Table Array. This array contains the information of the RSDT/XSDT
 150          * in a common, more useable format.
 151          */
 152         status =
 153             acpi_tb_parse_root_table(rsdp_address, ACPI_TABLE_ORIGIN_MAPPED);
 154         return_ACPI_STATUS(status);
 155 }
 156
 157 /*******************************************************************************
 158  *
 159  * FUNCTION:    acpi_reallocate_root_table
 160  *
 161  * PARAMETERS:  None
 162  *
 163  * RETURN:      Status
 164  *
 165  * DESCRIPTION: Reallocate Root Table List into dynamic memory. Copies the
 166  *              root list from the previously provided scratch area. Should
 167  *              be called once dynamic memory allocation is available in the
 168  *              kernel
 169  *
 170  ******************************************************************************/
 171 acpi_status acpi_reallocate_root_table(void)
 172 {
 173         struct acpi_table_desc *tables;
 174         acpi_size new_size;
 175
 176         ACPI_FUNCTION_TRACE(acpi_reallocate_root_table);
 177
 178         /*
 179          * Only reallocate the root table if the host provided a static buffer
 180          * for the table array in the call to acpi_initialize_tables.
 181          */
 182         if (acpi_gbl_root_table_list.flags & ACPI_ROOT_ORIGIN_ALLOCATED) {
 183                 return_ACPI_STATUS(AE_SUPPORT);
 184         }
 185
 186         new_size = ((acpi_size) acpi_gbl_root_table_list.count +
 187                     ACPI_ROOT_TABLE_SIZE_INCREMENT) *
 188             sizeof(struct acpi_table_desc);
 189
 190         /* Create new array and copy the old array */
 191
 192         tables = ACPI_ALLOCATE_ZEROED(new_size);
 193         if (!tables) {
 194                 return_ACPI_STATUS(AE_NO_MEMORY);
 195         }
 196
 197         ACPI_MEMCPY(tables, acpi_gbl_root_table_list.tables, new_size);
 198
 199         acpi_gbl_root_table_list.size = acpi_gbl_root_table_list.count;
 200         acpi_gbl_root_table_list.tables = tables;
 201         acpi_gbl_root_table_list.flags =
 202             ACPI_ROOT_ORIGIN_ALLOCATED | ACPI_ROOT_ALLOW_RESIZE;
 203
 204         return_ACPI_STATUS(AE_OK);
 205 }
 206
 207 /*******************************************************************************
 208  *
 209  * FUNCTION:    acpi_load_table
 210  *
 211  * PARAMETERS:  table_ptr       - pointer to a buffer containing the entire
 212  *                                table to be loaded
 213  *
 214  * RETURN:      Status
 215  *
 216  * DESCRIPTION: This function is called to load a table from the caller's
 217  *              buffer. The buffer must contain an entire ACPI Table including
 218  *              a valid header. The header fields will be verified, and if it
 219  *              is determined that the table is invalid, the call will fail.
 220  *
 221  ******************************************************************************/
 222 acpi_status acpi_load_table(struct acpi_table_header *table_ptr)
 223 {
 224         acpi_status status;
 225         u32 table_index;
 226         struct acpi_table_desc table_desc;
 227
 228         if (!table_ptr)
 229                 return AE_BAD_PARAMETER;
 230
 231         ACPI_MEMSET(&table_desc, 0, sizeof(struct acpi_table_desc));
 232         table_desc.pointer = table_ptr;
 233         table_desc.length = table_ptr->length;
 234         table_desc.flags = ACPI_TABLE_ORIGIN_UNKNOWN;
 235
 236         /*
 237          * Install the new table into the local data structures
 238          */
 239         status = acpi_tb_add_table(&table_desc, &table_index);
 240         if (ACPI_FAILURE(status)) {
 241                 return status;
 242         }
 243         status = acpi_ns_load_table(table_index, acpi_gbl_root_node);
 244         return status;
 245 }
 246
 247 ACPI_EXPORT_SYMBOL(acpi_load_table)
 248
 249 /******************************************************************************
 250  *
 251  * FUNCTION:    acpi_get_table_header
 252  *
 253  * PARAMETERS:  Signature           - ACPI signature of needed table
 254  *              Instance            - Which instance (for SSDTs)
 255  *              out_table_header    - The pointer to the table header to fill
 256  *
 257  * RETURN:      Status and pointer to mapped table header
 258  *
 259  * DESCRIPTION: Finds an ACPI table header.
 260  *
 261  * NOTE:        Caller is responsible in unmapping the header with
 262  *              acpi_os_unmap_memory
 263  *
 264  *****************************************************************************/
 265 acpi_status
 266 acpi_get_table_header(char *signature,
 267                       u32 instance, struct acpi_table_header *out_table_header)
 268 {
 269        u32 i;
 270        u32 j;
 271         struct acpi_table_header *header;
 272
 273         /* Parameter validation */
 274
 275         if (!signature || !out_table_header) {
 276                 return (AE_BAD_PARAMETER);
 277         }
 278
 279         /*
 280          * Walk the root table list
 281          */
 282         for (i = 0, j = 0; i < acpi_gbl_root_table_list.count; i++) {
 283                 if (!ACPI_COMPARE_NAME
 284                     (&(acpi_gbl_root_table_list.tables[i].signature),
 285                      signature)) {
 286                         continue;
 287                 }
 288
 289                 if (++j < instance) {
 290                         continue;
 291                 }
 292
 293                 if (!acpi_gbl_root_table_list.tables[i].pointer) {
 294                         if ((acpi_gbl_root_table_list.tables[i].
 295                              flags & ACPI_TABLE_ORIGIN_MASK) ==
 296                             ACPI_TABLE_ORIGIN_MAPPED) {
 297                                 header =
 298                                     acpi_os_map_memory(acpi_gbl_root_table_list.
 299                                                        tables[i].address,
 300                                                        sizeof(struct
 301                                                               acpi_table_header));
 302                                 if (!header) {
 303                                         return AE_NO_MEMORY;
 304                                 }
 305                                 ACPI_MEMCPY(out_table_header, header,
 306                                             sizeof(struct acpi_table_header));
 307                                 acpi_os_unmap_memory(header,
 308                                                      sizeof(struct
 309                                                             acpi_table_header));
 310                         } else {
 311                                 return AE_NOT_FOUND;
 312                         }
 313                 } else {
 314                         ACPI_MEMCPY(out_table_header,
 315                                     acpi_gbl_root_table_list.tables[i].pointer,
 316                                     sizeof(struct acpi_table_header));
 317                 }
 318                 return (AE_OK);
 319         }
 320
 321         return (AE_NOT_FOUND);
 322 }
 323
 324 ACPI_EXPORT_SYMBOL(acpi_get_table_header)
 325
 326 /******************************************************************************
 327  *
 328  * FUNCTION:    acpi_unload_table_id
 329  *
 330  * PARAMETERS:  id            - Owner ID of the table to be removed.
 331  *
 332  * RETURN:      Status
 333  *
 334  * DESCRIPTION: This routine is used to force the unload of a table (by id)
 335  *
 336  ******************************************************************************/
 337 acpi_status acpi_unload_table_id(acpi_owner_id id)
 338 {
 339         int i;
 340         acpi_status status = AE_NOT_EXIST;
 341
 342         ACPI_FUNCTION_TRACE(acpi_unload_table_id);
 343
 344         /* Find table in the global table list */
 345         for (i = 0; i < acpi_gbl_root_table_list.count; ++i) {
 346                 if (id != acpi_gbl_root_table_list.tables[i].owner_id) {
 347                         continue;
 348                 }
 349                 /*
 350                  * Delete all namespace objects owned by this table. Note that these
 351                  * objects can appear anywhere in the namespace by virtue of the AML
 352                  * "Scope" operator. Thus, we need to track ownership by an ID, not
 353                  * simply a position within the hierarchy
 354                  */
 355                 acpi_tb_delete_namespace_by_owner(i);
 356                 status = acpi_tb_release_owner_id(i);
 357                 acpi_tb_set_table_loaded_flag(i, FALSE);
 358                 break;
 359         }
 360         return_ACPI_STATUS(status);
 361 }
 362
 363 ACPI_EXPORT_SYMBOL(acpi_unload_table_id)
 364
 365 /*******************************************************************************
 366  *
 367  * FUNCTION:    acpi_get_table
 368  *
 369  * PARAMETERS:  Signature           - ACPI signature of needed table
 370  *              Instance            - Which instance (for SSDTs)
 371  *              out_table           - Where the pointer to the table is returned
 372  *
 373  * RETURN:      Status and pointer to table
 374  *
 375  * DESCRIPTION: Finds and verifies an ACPI table.
 376  *
 377  *****************************************************************************/
 378 acpi_status
 379 acpi_get_table(char *signature,
 380                u32 instance, struct acpi_table_header **out_table)
 381 {
 382        u32 i;
 383        u32 j;
 384         acpi_status status;
 385
 386         /* Parameter validation */
 387
 388         if (!signature || !out_table) {
 389                 return (AE_BAD_PARAMETER);
 390         }
 391
 392         /*
 393          * Walk the root table list
 394          */
 395         for (i = 0, j = 0; i < acpi_gbl_root_table_list.count; i++) {
 396                 if (!ACPI_COMPARE_NAME
 397                     (&(acpi_gbl_root_table_list.tables[i].signature),
 398                      signature)) {
 399                         continue;
 400                 }
 401
 402                 if (++j < instance) {
 403                         continue;
 404                 }
 405
 406                 status =
 407                     acpi_tb_verify_table(&acpi_gbl_root_table_list.tables[i]);
 408                 if (ACPI_SUCCESS(status)) {
 409                         *out_table = acpi_gbl_root_table_list.tables[i].pointer;
 410                 }
 411
 412                 if (!acpi_gbl_permanent_mmap) {
 413                         acpi_gbl_root_table_list.tables[i].pointer = NULL;
 414                 }
 415
 416                 return (status);
 417         }
 418
 419         return (AE_NOT_FOUND);
 420 }
 421
 422 ACPI_EXPORT_SYMBOL(acpi_get_table)
 423
 424 /*******************************************************************************
 425  *
 426  * FUNCTION:    acpi_get_table_by_index
 427  *
 428  * PARAMETERS:  table_index         - Table index
 429  *              Table               - Where the pointer to the table is returned
 430  *
 431  * RETURN:      Status and pointer to the table
 432  *
 433  * DESCRIPTION: Obtain a table by an index into the global table list.
 434  *
 435  ******************************************************************************/
 436 acpi_status
 437 acpi_get_table_by_index(u32 table_index, struct acpi_table_header **table)
 438 {
 439         acpi_status status;
 440
 441         ACPI_FUNCTION_TRACE(acpi_get_table_by_index);
 442
 443         /* Parameter validation */
 444
 445         if (!table) {
 446                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 447         }
 448
 449         (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
 450
 451         /* Validate index */
 452
 453         if (table_index >= acpi_gbl_root_table_list.count) {
 454                 (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
 455                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 456         }
 457
 458         if (!acpi_gbl_root_table_list.tables[table_index].pointer) {
 459
 460                 /* Table is not mapped, map it */
 461
 462                 status =
 463                     acpi_tb_verify_table(&acpi_gbl_root_table_list.
 464                                          tables[table_index]);
 465                 if (ACPI_FAILURE(status)) {
 466                         (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
 467                         return_ACPI_STATUS(status);
 468                 }
 469         }
 470
 471         *table = acpi_gbl_root_table_list.tables[table_index].pointer;
 472         (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
 473         return_ACPI_STATUS(AE_OK);
 474 }
 475
 476 ACPI_EXPORT_SYMBOL(acpi_get_table_by_index)
 477
 478 /*******************************************************************************
 479  *
 480  * FUNCTION:    acpi_tb_load_namespace
 481  *
 482  * PARAMETERS:  None
 483  *
 484  * RETURN:      Status
 485  *
 486  * DESCRIPTION: Load the namespace from the DSDT and all SSDTs/PSDTs found in
 487  *              the RSDT/XSDT.
 488  *
 489  ******************************************************************************/
 490 static acpi_status acpi_tb_load_namespace(void)
 491 {
 492         acpi_status status;
 493         struct acpi_table_header *table;
 494         u32 i;
 495
 496         ACPI_FUNCTION_TRACE(tb_load_namespace);
 497
 498         (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
 499
 500         /*
 501          * Load the namespace. The DSDT is required, but any SSDT and PSDT tables
 502          * are optional.
 503          */
 504         if (!acpi_gbl_root_table_list.count ||
 505             !ACPI_COMPARE_NAME(&
 506                                (acpi_gbl_root_table_list.
 507                                 tables[ACPI_TABLE_INDEX_DSDT].signature),
 508                                ACPI_SIG_DSDT)
 509             ||
 510             ACPI_FAILURE(acpi_tb_verify_table
 511                          (&acpi_gbl_root_table_list.
 512                           tables[ACPI_TABLE_INDEX_DSDT]))) {
 513                 status = AE_NO_ACPI_TABLES;
 514                 goto unlock_and_exit;
 515         }
 516
 517         /*
 518          * Find DSDT table
 519          */
 520         status =
 521             acpi_os_table_override(acpi_gbl_root_table_list.
 522                                    tables[ACPI_TABLE_INDEX_DSDT].pointer,
 523                                    &table);
 524         if (ACPI_SUCCESS(status) && table) {
 525                 /*
 526                  * DSDT table has been found
 527                  */
 528                 acpi_tb_delete_table(&acpi_gbl_root_table_list.
 529                                      tables[ACPI_TABLE_INDEX_DSDT]);
 530                 acpi_gbl_root_table_list.tables[ACPI_TABLE_INDEX_DSDT].pointer =
 531                     table;
 532                 acpi_gbl_root_table_list.tables[ACPI_TABLE_INDEX_DSDT].length =
 533                     table->length;
 534                 acpi_gbl_root_table_list.tables[ACPI_TABLE_INDEX_DSDT].flags =
 535                     ACPI_TABLE_ORIGIN_UNKNOWN;
 536
 537                 ACPI_INFO((AE_INFO, "Table DSDT replaced by host OS"));
 538                 acpi_tb_print_table_header(0, table);
 539
 540                 if (no_auto_ssdt == 0) {
 541                         printk(KERN_WARNING "ACPI: DSDT override uses original SSDTs unless \"acpi_no_auto_ssdt\"\n");
 542                 }
 543         }
 544
 545         status =
 546             acpi_tb_verify_table(&acpi_gbl_root_table_list.
 547                                  tables[ACPI_TABLE_INDEX_DSDT]);
 548         if (ACPI_FAILURE(status)) {
 549
 550                 /* A valid DSDT is required */
 551
 552                 status = AE_NO_ACPI_TABLES;
 553                 goto unlock_and_exit;
 554         }
 555
 556         (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
 557
 558         /*
 559          * Load and parse tables.
 560          */
 561         status = acpi_ns_load_table(ACPI_TABLE_INDEX_DSDT, acpi_gbl_root_node);
 562         if (ACPI_FAILURE(status)) {
 563                 return_ACPI_STATUS(status);
 564         }
 565
 566         /*
 567          * Load any SSDT or PSDT tables. Note: Loop leaves tables locked
 568          */
 569         (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
 570         for (i = 0; i < acpi_gbl_root_table_list.count; ++i) {
 571                 if ((!ACPI_COMPARE_NAME
 572                      (&(acpi_gbl_root_table_list.tables[i].signature),
 573                       ACPI_SIG_SSDT)
 574                      &&
 575                      !ACPI_COMPARE_NAME(&
 576                                         (acpi_gbl_root_table_list.tables[i].
 577                                          signature), ACPI_SIG_PSDT))
 578                     ||
 579                     ACPI_FAILURE(acpi_tb_verify_table
 580                                  (&acpi_gbl_root_table_list.tables[i]))) {
 581                         continue;
 582                 }
 583
 584                 if (no_auto_ssdt) {
 585                         printk(KERN_WARNING "ACPI: SSDT ignored due to \"acpi_no_auto_ssdt\"\n");
 586                         continue;
 587                 }
 588
 589                 /* Ignore errors while loading tables, get as many as possible */
 590
 591                 (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
 592                 (void)acpi_ns_load_table(i, acpi_gbl_root_node);
 593                 (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
 594         }
 595
 596         ACPI_DEBUG_PRINT((ACPI_DB_INIT, "ACPI Tables successfully acquired\n"));
 597
 598       unlock_and_exit:
 599         (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
 600         return_ACPI_STATUS(status);
 601 }
 602
 603 /*******************************************************************************
 604  *
 605  * FUNCTION:    acpi_load_tables
 606  *
 607  * PARAMETERS:  None
 608  *
 609  * RETURN:      Status
 610  *
 611  * DESCRIPTION: Load the ACPI tables from the RSDT/XSDT
 612  *
 613  ******************************************************************************/
 614
 615 acpi_status acpi_load_tables(void)
 616 {
 617         acpi_status status;
 618
 619         ACPI_FUNCTION_TRACE(acpi_load_tables);
 620
 621         /*
 622          * Load the namespace from the tables
 623          */
 624         status = acpi_tb_load_namespace();
 625         if (ACPI_FAILURE(status)) {
 626                 ACPI_EXCEPTION((AE_INFO, status,
 627                                 "While loading namespace from ACPI tables"));
 628         }
 629
 630         return_ACPI_STATUS(status);
 631 }
 632
 633 ACPI_EXPORT_SYMBOL(acpi_load_tables)
 634
 635
 636 /*******************************************************************************
 637  *
 638  * FUNCTION:    acpi_install_table_handler
 639  *
 640  * PARAMETERS:  Handler         - Table event handler
 641  *              Context         - Value passed to the handler on each event
 642  *
 643  * RETURN:      Status
 644  *
 645  * DESCRIPTION: Install table event handler
 646  *
 647  ******************************************************************************/
 648 acpi_status
 649 acpi_install_table_handler(acpi_tbl_handler handler, void *context)
 650 {
 651         acpi_status status;
 652
 653         ACPI_FUNCTION_TRACE(acpi_install_table_handler);
 654
 655         if (!handler) {
 656                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 657         }
 658
 659         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 660         if (ACPI_FAILURE(status)) {
 661                 return_ACPI_STATUS(status);
 662         }
 663
 664         /* Don't allow more than one handler */
 665
 666         if (acpi_gbl_table_handler) {
 667                 status = AE_ALREADY_EXISTS;
 668                 goto cleanup;
 669         }
 670
 671         /* Install the handler */
 672
 673         acpi_gbl_table_handler = handler;
 674         acpi_gbl_table_handler_context = context;
 675
 676       cleanup:
 677         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 678         return_ACPI_STATUS(status);
 679 }
 680
 681 ACPI_EXPORT_SYMBOL(acpi_install_table_handler)
 682
 683 /*******************************************************************************
 684  *
 685  * FUNCTION:    acpi_remove_table_handler
 686  *
 687  * PARAMETERS:  Handler         - Table event handler that was installed
 688  *                                previously.
 689  *
 690  * RETURN:      Status
 691  *
 692  * DESCRIPTION: Remove table event handler
 693  *
 694  ******************************************************************************/
 695 acpi_status acpi_remove_table_handler(acpi_tbl_handler handler)
 696 {
 697         acpi_status status;
 698
 699         ACPI_FUNCTION_TRACE(acpi_remove_table_handler);
 700
 701         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 702         if (ACPI_FAILURE(status)) {
 703                 return_ACPI_STATUS(status);
 704         }
 705
 706         /* Make sure that the installed handler is the same */
 707
 708         if (!handler || handler != acpi_gbl_table_handler) {
 709                 status = AE_BAD_PARAMETER;
 710                 goto cleanup;
 711         }
 712
 713         /* Remove the handler */
 714
 715         acpi_gbl_table_handler = NULL;
 716
 717       cleanup:
 718         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 719         return_ACPI_STATUS(status);
 720 }
 721
 722 ACPI_EXPORT_SYMBOL(acpi_remove_table_handler)
 723
 724
 725 static int __init acpi_no_auto_ssdt_setup(char *s) {
 726
 727         printk(KERN_NOTICE "ACPI: SSDT auto-load disabled\n");
 728
 729         no_auto_ssdt = 1;
 730
 731         return 1;
 732 }
 733
 734 __setup("acpi_no_auto_ssdt", acpi_no_auto_ssdt_setup);