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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);