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_with_size 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_with_size(char *signature, 381 u32 instance, struct acpi_table_header **out_table, 382 acpi_size *tbl_size) 383 { 384 u32 i; 385 u32 j; 386 acpi_status status; 387 388 /* Parameter validation */ 389 390 if (!signature || !out_table) { 391 return (AE_BAD_PARAMETER); 392 } 393 394 /* 395 * Walk the root table list 396 */ 397 for (i = 0, j = 0; i < acpi_gbl_root_table_list.count; i++) { 398 if (!ACPI_COMPARE_NAME 399 (&(acpi_gbl_root_table_list.tables[i].signature), 400 signature)) { 401 continue; 402 } 403 404 if (++j < instance) { 405 continue; 406 } 407 408 status = 409 acpi_tb_verify_table(&acpi_gbl_root_table_list.tables[i]); 410 if (ACPI_SUCCESS(status)) { 411 *out_table = acpi_gbl_root_table_list.tables[i].pointer; 412 *tbl_size = acpi_gbl_root_table_list.tables[i].length; 413 } 414 415 if (!acpi_gbl_permanent_mmap) { 416 acpi_gbl_root_table_list.tables[i].pointer = NULL; 417 } 418 419 return (status); 420 } 421 422 return (AE_NOT_FOUND); 423 } 424 425 acpi_status 426 acpi_get_table(char *signature, 427 u32 instance, struct acpi_table_header **out_table) 428 { 429 acpi_size tbl_size; 430 431 return acpi_get_table_with_size(signature, 432 instance, out_table, &tbl_size); 433 } 434 ACPI_EXPORT_SYMBOL(acpi_get_table) 435 436 /******************************************************************************* 437 * 438 * FUNCTION: acpi_get_table_by_index 439 * 440 * PARAMETERS: table_index - Table index 441 * Table - Where the pointer to the table is returned 442 * 443 * RETURN: Status and pointer to the table 444 * 445 * DESCRIPTION: Obtain a table by an index into the global table list. 446 * 447 ******************************************************************************/ 448 acpi_status 449 acpi_get_table_by_index(u32 table_index, struct acpi_table_header **table) 450 { 451 acpi_status status; 452 453 ACPI_FUNCTION_TRACE(acpi_get_table_by_index); 454 455 /* Parameter validation */ 456 457 if (!table) { 458 return_ACPI_STATUS(AE_BAD_PARAMETER); 459 } 460 461 (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES); 462 463 /* Validate index */ 464 465 if (table_index >= acpi_gbl_root_table_list.count) { 466 (void)acpi_ut_release_mutex(ACPI_MTX_TABLES); 467 return_ACPI_STATUS(AE_BAD_PARAMETER); 468 } 469 470 if (!acpi_gbl_root_table_list.tables[table_index].pointer) { 471 472 /* Table is not mapped, map it */ 473 474 status = 475 acpi_tb_verify_table(&acpi_gbl_root_table_list. 476 tables[table_index]); 477 if (ACPI_FAILURE(status)) { 478 (void)acpi_ut_release_mutex(ACPI_MTX_TABLES); 479 return_ACPI_STATUS(status); 480 } 481 } 482 483 *table = acpi_gbl_root_table_list.tables[table_index].pointer; 484 (void)acpi_ut_release_mutex(ACPI_MTX_TABLES); 485 return_ACPI_STATUS(AE_OK); 486 } 487 488 ACPI_EXPORT_SYMBOL(acpi_get_table_by_index) 489 490 /******************************************************************************* 491 * 492 * FUNCTION: acpi_tb_load_namespace 493 * 494 * PARAMETERS: None 495 * 496 * RETURN: Status 497 * 498 * DESCRIPTION: Load the namespace from the DSDT and all SSDTs/PSDTs found in 499 * the RSDT/XSDT. 500 * 501 ******************************************************************************/ 502 static acpi_status acpi_tb_load_namespace(void) 503 { 504 acpi_status status; 505 struct acpi_table_header *table; 506 u32 i; 507 508 ACPI_FUNCTION_TRACE(tb_load_namespace); 509 510 (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES); 511 512 /* 513 * Load the namespace. The DSDT is required, but any SSDT and PSDT tables 514 * are optional. 515 */ 516 if (!acpi_gbl_root_table_list.count || 517 !ACPI_COMPARE_NAME(& 518 (acpi_gbl_root_table_list. 519 tables[ACPI_TABLE_INDEX_DSDT].signature), 520 ACPI_SIG_DSDT) 521 || 522 ACPI_FAILURE(acpi_tb_verify_table 523 (&acpi_gbl_root_table_list. 524 tables[ACPI_TABLE_INDEX_DSDT]))) { 525 status = AE_NO_ACPI_TABLES; 526 goto unlock_and_exit; 527 } 528 529 /* 530 * Find DSDT table 531 */ 532 status = 533 acpi_os_table_override(acpi_gbl_root_table_list. 534 tables[ACPI_TABLE_INDEX_DSDT].pointer, 535 &table); 536 if (ACPI_SUCCESS(status) && table) { 537 /* 538 * DSDT table has been found 539 */ 540 acpi_tb_delete_table(&acpi_gbl_root_table_list. 541 tables[ACPI_TABLE_INDEX_DSDT]); 542 acpi_gbl_root_table_list.tables[ACPI_TABLE_INDEX_DSDT].pointer = 543 table; 544 acpi_gbl_root_table_list.tables[ACPI_TABLE_INDEX_DSDT].length = 545 table->length; 546 acpi_gbl_root_table_list.tables[ACPI_TABLE_INDEX_DSDT].flags = 547 ACPI_TABLE_ORIGIN_UNKNOWN; 548 549 ACPI_INFO((AE_INFO, "Table DSDT replaced by host OS")); 550 acpi_tb_print_table_header(0, table); 551 552 if (no_auto_ssdt == 0) { 553 printk(KERN_WARNING "ACPI: DSDT override uses original SSDTs unless \"acpi_no_auto_ssdt\"\n"); 554 } 555 } 556 557 status = 558 acpi_tb_verify_table(&acpi_gbl_root_table_list. 559 tables[ACPI_TABLE_INDEX_DSDT]); 560 if (ACPI_FAILURE(status)) { 561 562 /* A valid DSDT is required */ 563 564 status = AE_NO_ACPI_TABLES; 565 goto unlock_and_exit; 566 } 567 568 (void)acpi_ut_release_mutex(ACPI_MTX_TABLES); 569 570 /* 571 * Load and parse tables. 572 */ 573 status = acpi_ns_load_table(ACPI_TABLE_INDEX_DSDT, acpi_gbl_root_node); 574 if (ACPI_FAILURE(status)) { 575 return_ACPI_STATUS(status); 576 } 577 578 /* 579 * Load any SSDT or PSDT tables. Note: Loop leaves tables locked 580 */ 581 (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES); 582 for (i = 0; i < acpi_gbl_root_table_list.count; ++i) { 583 if ((!ACPI_COMPARE_NAME 584 (&(acpi_gbl_root_table_list.tables[i].signature), 585 ACPI_SIG_SSDT) 586 && 587 !ACPI_COMPARE_NAME(& 588 (acpi_gbl_root_table_list.tables[i]. 589 signature), ACPI_SIG_PSDT)) 590 || 591 ACPI_FAILURE(acpi_tb_verify_table 592 (&acpi_gbl_root_table_list.tables[i]))) { 593 continue; 594 } 595 596 if (no_auto_ssdt) { 597 printk(KERN_WARNING "ACPI: SSDT ignored due to \"acpi_no_auto_ssdt\"\n"); 598 continue; 599 } 600 601 /* Ignore errors while loading tables, get as many as possible */ 602 603 (void)acpi_ut_release_mutex(ACPI_MTX_TABLES); 604 (void)acpi_ns_load_table(i, acpi_gbl_root_node); 605 (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES); 606 } 607 608 ACPI_DEBUG_PRINT((ACPI_DB_INIT, "ACPI Tables successfully acquired\n")); 609 610 unlock_and_exit: 611 (void)acpi_ut_release_mutex(ACPI_MTX_TABLES); 612 return_ACPI_STATUS(status); 613 } 614 615 /******************************************************************************* 616 * 617 * FUNCTION: acpi_load_tables 618 * 619 * PARAMETERS: None 620 * 621 * RETURN: Status 622 * 623 * DESCRIPTION: Load the ACPI tables from the RSDT/XSDT 624 * 625 ******************************************************************************/ 626 627 acpi_status acpi_load_tables(void) 628 { 629 acpi_status status; 630 631 ACPI_FUNCTION_TRACE(acpi_load_tables); 632 633 /* 634 * Load the namespace from the tables 635 */ 636 status = acpi_tb_load_namespace(); 637 if (ACPI_FAILURE(status)) { 638 ACPI_EXCEPTION((AE_INFO, status, 639 "While loading namespace from ACPI tables")); 640 } 641 642 return_ACPI_STATUS(status); 643 } 644 645 ACPI_EXPORT_SYMBOL(acpi_load_tables) 646 647 648 /******************************************************************************* 649 * 650 * FUNCTION: acpi_install_table_handler 651 * 652 * PARAMETERS: Handler - Table event handler 653 * Context - Value passed to the handler on each event 654 * 655 * RETURN: Status 656 * 657 * DESCRIPTION: Install table event handler 658 * 659 ******************************************************************************/ 660 acpi_status 661 acpi_install_table_handler(acpi_tbl_handler handler, void *context) 662 { 663 acpi_status status; 664 665 ACPI_FUNCTION_TRACE(acpi_install_table_handler); 666 667 if (!handler) { 668 return_ACPI_STATUS(AE_BAD_PARAMETER); 669 } 670 671 status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS); 672 if (ACPI_FAILURE(status)) { 673 return_ACPI_STATUS(status); 674 } 675 676 /* Don't allow more than one handler */ 677 678 if (acpi_gbl_table_handler) { 679 status = AE_ALREADY_EXISTS; 680 goto cleanup; 681 } 682 683 /* Install the handler */ 684 685 acpi_gbl_table_handler = handler; 686 acpi_gbl_table_handler_context = context; 687 688 cleanup: 689 (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS); 690 return_ACPI_STATUS(status); 691 } 692 693 ACPI_EXPORT_SYMBOL(acpi_install_table_handler) 694 695 /******************************************************************************* 696 * 697 * FUNCTION: acpi_remove_table_handler 698 * 699 * PARAMETERS: Handler - Table event handler that was installed 700 * previously. 701 * 702 * RETURN: Status 703 * 704 * DESCRIPTION: Remove table event handler 705 * 706 ******************************************************************************/ 707 acpi_status acpi_remove_table_handler(acpi_tbl_handler handler) 708 { 709 acpi_status status; 710 711 ACPI_FUNCTION_TRACE(acpi_remove_table_handler); 712 713 status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS); 714 if (ACPI_FAILURE(status)) { 715 return_ACPI_STATUS(status); 716 } 717 718 /* Make sure that the installed handler is the same */ 719 720 if (!handler || handler != acpi_gbl_table_handler) { 721 status = AE_BAD_PARAMETER; 722 goto cleanup; 723 } 724 725 /* Remove the handler */ 726 727 acpi_gbl_table_handler = NULL; 728 729 cleanup: 730 (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS); 731 return_ACPI_STATUS(status); 732 } 733 734 ACPI_EXPORT_SYMBOL(acpi_remove_table_handler) 735 736 737 static int __init acpi_no_auto_ssdt_setup(char *s) { 738 739 printk(KERN_NOTICE "ACPI: SSDT auto-load disabled\n"); 740 741 no_auto_ssdt = 1; 742 743 return 1; 744 } 745 746 __setup("acpi_no_auto_ssdt", acpi_no_auto_ssdt_setup); 747