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