]> err.no Git - linux-2.6/blob - drivers/acpi/tables/tbxface.c
Merge branch 'release' of git://lm-sensors.org/kernel/mhoffman/hwmon-2.6
[linux-2.6] / 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                             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 =
187             (acpi_gbl_root_table_list.count +
188              ACPI_ROOT_TABLE_SIZE_INCREMENT) * 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         acpi_native_uint 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                       acpi_native_uint instance,
268                       struct acpi_table_header * out_table_header)
269 {
270         acpi_native_uint i;
271         acpi_native_uint 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                acpi_native_uint instance, struct acpi_table_header **out_table)
382 {
383         acpi_native_uint i;
384         acpi_native_uint 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(acpi_native_uint table_index,
439                         struct acpi_table_header ** table)
440 {
441         acpi_status status;
442
443         ACPI_FUNCTION_TRACE(acpi_get_table_by_index);
444
445         /* Parameter validation */
446
447         if (!table) {
448                 return_ACPI_STATUS(AE_BAD_PARAMETER);
449         }
450
451         (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
452
453         /* Validate index */
454
455         if (table_index >= acpi_gbl_root_table_list.count) {
456                 (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
457                 return_ACPI_STATUS(AE_BAD_PARAMETER);
458         }
459
460         if (!acpi_gbl_root_table_list.tables[table_index].pointer) {
461
462                 /* Table is not mapped, map it */
463
464                 status =
465                     acpi_tb_verify_table(&acpi_gbl_root_table_list.
466                                          tables[table_index]);
467                 if (ACPI_FAILURE(status)) {
468                         (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
469                         return_ACPI_STATUS(status);
470                 }
471         }
472
473         *table = acpi_gbl_root_table_list.tables[table_index].pointer;
474         (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
475         return_ACPI_STATUS(AE_OK);
476 }
477
478 ACPI_EXPORT_SYMBOL(acpi_get_table_by_index)
479
480 /*******************************************************************************
481  *
482  * FUNCTION:    acpi_tb_load_namespace
483  *
484  * PARAMETERS:  None
485  *
486  * RETURN:      Status
487  *
488  * DESCRIPTION: Load the namespace from the DSDT and all SSDTs/PSDTs found in
489  *              the RSDT/XSDT.
490  *
491  ******************************************************************************/
492 static acpi_status acpi_tb_load_namespace(void)
493 {
494         acpi_status status;
495         struct acpi_table_header *table;
496         acpi_native_uint i;
497
498         ACPI_FUNCTION_TRACE(tb_load_namespace);
499
500         (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
501
502         /*
503          * Load the namespace. The DSDT is required, but any SSDT and PSDT tables
504          * are optional.
505          */
506         if (!acpi_gbl_root_table_list.count ||
507             !ACPI_COMPARE_NAME(&
508                                (acpi_gbl_root_table_list.
509                                 tables[ACPI_TABLE_INDEX_DSDT].signature),
510                                ACPI_SIG_DSDT)
511             ||
512             ACPI_FAILURE(acpi_tb_verify_table
513                          (&acpi_gbl_root_table_list.
514                           tables[ACPI_TABLE_INDEX_DSDT]))) {
515                 status = AE_NO_ACPI_TABLES;
516                 goto unlock_and_exit;
517         }
518
519         /*
520          * Find DSDT table
521          */
522         status =
523             acpi_os_table_override(acpi_gbl_root_table_list.
524                                    tables[ACPI_TABLE_INDEX_DSDT].pointer,
525                                    &table);
526         if (ACPI_SUCCESS(status) && table) {
527                 /*
528                  * DSDT table has been found
529                  */
530                 acpi_tb_delete_table(&acpi_gbl_root_table_list.
531                                      tables[ACPI_TABLE_INDEX_DSDT]);
532                 acpi_gbl_root_table_list.tables[ACPI_TABLE_INDEX_DSDT].pointer =
533                     table;
534                 acpi_gbl_root_table_list.tables[ACPI_TABLE_INDEX_DSDT].length =
535                     table->length;
536                 acpi_gbl_root_table_list.tables[ACPI_TABLE_INDEX_DSDT].flags =
537                     ACPI_TABLE_ORIGIN_UNKNOWN;
538
539                 ACPI_INFO((AE_INFO, "Table DSDT replaced by host OS"));
540                 acpi_tb_print_table_header(0, table);
541
542                 if (no_auto_ssdt == 0) {
543                         printk(KERN_WARNING "ACPI: DSDT override uses original SSDTs unless \"acpi_no_auto_ssdt\"");
544                 }
545         }
546
547         status =
548             acpi_tb_verify_table(&acpi_gbl_root_table_list.
549                                  tables[ACPI_TABLE_INDEX_DSDT]);
550         if (ACPI_FAILURE(status)) {
551
552                 /* A valid DSDT is required */
553
554                 status = AE_NO_ACPI_TABLES;
555                 goto unlock_and_exit;
556         }
557
558         (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
559
560         /*
561          * Load and parse tables.
562          */
563         status = acpi_ns_load_table(ACPI_TABLE_INDEX_DSDT, acpi_gbl_root_node);
564         if (ACPI_FAILURE(status)) {
565                 return_ACPI_STATUS(status);
566         }
567
568         /*
569          * Load any SSDT or PSDT tables. Note: Loop leaves tables locked
570          */
571         (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
572         for (i = 0; i < acpi_gbl_root_table_list.count; ++i) {
573                 if ((!ACPI_COMPARE_NAME
574                      (&(acpi_gbl_root_table_list.tables[i].signature),
575                       ACPI_SIG_SSDT)
576                      &&
577                      !ACPI_COMPARE_NAME(&
578                                         (acpi_gbl_root_table_list.tables[i].
579                                          signature), ACPI_SIG_PSDT))
580                     ||
581                     ACPI_FAILURE(acpi_tb_verify_table
582                                  (&acpi_gbl_root_table_list.tables[i]))) {
583                         continue;
584                 }
585
586                 if (no_auto_ssdt) {
587                         printk(KERN_WARNING "ACPI: SSDT ignored due to \"acpi_no_auto_ssdt\"\n");
588                         continue;
589                 }
590
591                 /* Ignore errors while loading tables, get as many as possible */
592
593                 (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
594                 (void)acpi_ns_load_table(i, acpi_gbl_root_node);
595                 (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
596         }
597
598         ACPI_DEBUG_PRINT((ACPI_DB_INIT, "ACPI Tables successfully acquired\n"));
599
600       unlock_and_exit:
601         (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
602         return_ACPI_STATUS(status);
603 }
604
605 /*******************************************************************************
606  *
607  * FUNCTION:    acpi_load_tables
608  *
609  * PARAMETERS:  None
610  *
611  * RETURN:      Status
612  *
613  * DESCRIPTION: Load the ACPI tables from the RSDT/XSDT
614  *
615  ******************************************************************************/
616
617 acpi_status acpi_load_tables(void)
618 {
619         acpi_status status;
620
621         ACPI_FUNCTION_TRACE(acpi_load_tables);
622
623         /*
624          * Load the namespace from the tables
625          */
626         status = acpi_tb_load_namespace();
627         if (ACPI_FAILURE(status)) {
628                 ACPI_EXCEPTION((AE_INFO, status,
629                                 "While loading namespace from ACPI tables"));
630         }
631
632         return_ACPI_STATUS(status);
633 }
634
635 ACPI_EXPORT_SYMBOL(acpi_load_tables)
636
637
638 /*******************************************************************************
639  *
640  * FUNCTION:    acpi_install_table_handler
641  *
642  * PARAMETERS:  Handler         - Table event handler
643  *              Context         - Value passed to the handler on each event
644  *
645  * RETURN:      Status
646  *
647  * DESCRIPTION: Install table event handler
648  *
649  ******************************************************************************/
650 acpi_status
651 acpi_install_table_handler(acpi_tbl_handler handler, void *context)
652 {
653         acpi_status status;
654
655         ACPI_FUNCTION_TRACE(acpi_install_table_handler);
656
657         if (!handler) {
658                 return_ACPI_STATUS(AE_BAD_PARAMETER);
659         }
660
661         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
662         if (ACPI_FAILURE(status)) {
663                 return_ACPI_STATUS(status);
664         }
665
666         /* Don't allow more than one handler */
667
668         if (acpi_gbl_table_handler) {
669                 status = AE_ALREADY_EXISTS;
670                 goto cleanup;
671         }
672
673         /* Install the handler */
674
675         acpi_gbl_table_handler = handler;
676         acpi_gbl_table_handler_context = context;
677
678       cleanup:
679         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
680         return_ACPI_STATUS(status);
681 }
682
683 ACPI_EXPORT_SYMBOL(acpi_install_table_handler)
684
685 /*******************************************************************************
686  *
687  * FUNCTION:    acpi_remove_table_handler
688  *
689  * PARAMETERS:  Handler         - Table event handler that was installed
690  *                                previously.
691  *
692  * RETURN:      Status
693  *
694  * DESCRIPTION: Remove table event handler
695  *
696  ******************************************************************************/
697 acpi_status acpi_remove_table_handler(acpi_tbl_handler handler)
698 {
699         acpi_status status;
700
701         ACPI_FUNCTION_TRACE(acpi_remove_table_handler);
702
703         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
704         if (ACPI_FAILURE(status)) {
705                 return_ACPI_STATUS(status);
706         }
707
708         /* Make sure that the installed handler is the same */
709
710         if (!handler || handler != acpi_gbl_table_handler) {
711                 status = AE_BAD_PARAMETER;
712                 goto cleanup;
713         }
714
715         /* Remove the handler */
716
717         acpi_gbl_table_handler = NULL;
718
719       cleanup:
720         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
721         return_ACPI_STATUS(status);
722 }
723
724 ACPI_EXPORT_SYMBOL(acpi_remove_table_handler)
725
726
727 static int __init acpi_no_auto_ssdt_setup(char *s) {
728
729         printk(KERN_NOTICE "ACPI: SSDT auto-load disabled\n");
730
731         no_auto_ssdt = 1;
732
733         return 1;
734 }
735
736 __setup("acpi_no_auto_ssdt", acpi_no_auto_ssdt_setup);