Revert "ARM: tegra: tegratab: dummy change"
[linux-2.6.git] / 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 - 2012, 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 <linux/export.h>
46 #include <acpi/acpi.h>
47 #include "accommon.h"
48 #include "acnamesp.h"
49 #include "actables.h"
50
51 #define _COMPONENT          ACPI_TABLES
52 ACPI_MODULE_NAME("tbxface")
53
54 /* Local prototypes */
55 static acpi_status acpi_tb_load_namespace(void);
56
57 static int no_auto_ssdt;
58
59 /*******************************************************************************
60  *
61  * FUNCTION:    acpi_allocate_root_table
62  *
63  * PARAMETERS:  initial_table_count - Size of initial_table_array, in number of
64  *                                    struct acpi_table_desc structures
65  *
66  * RETURN:      Status
67  *
68  * DESCRIPTION: Allocate a root table array. Used by i_aSL compiler and
69  *              acpi_initialize_tables.
70  *
71  ******************************************************************************/
72
73 acpi_status acpi_allocate_root_table(u32 initial_table_count)
74 {
75
76         acpi_gbl_root_table_list.max_table_count = initial_table_count;
77         acpi_gbl_root_table_list.flags = ACPI_ROOT_ALLOW_RESIZE;
78
79         return (acpi_tb_resize_root_table_list());
80 }
81
82 /*******************************************************************************
83  *
84  * FUNCTION:    acpi_initialize_tables
85  *
86  * PARAMETERS:  initial_table_array - Pointer to an array of pre-allocated
87  *                                    struct acpi_table_desc structures. If NULL, the
88  *                                    array is dynamically allocated.
89  *              initial_table_count - Size of initial_table_array, in number of
90  *                                    struct acpi_table_desc structures
91  *              allow_realloc       - Flag to tell Table Manager if resize of
92  *                                    pre-allocated array is allowed. Ignored
93  *                                    if initial_table_array is NULL.
94  *
95  * RETURN:      Status
96  *
97  * DESCRIPTION: Initialize the table manager, get the RSDP and RSDT/XSDT.
98  *
99  * NOTE:        Allows static allocation of the initial table array in order
100  *              to avoid the use of dynamic memory in confined environments
101  *              such as the kernel boot sequence where it may not be available.
102  *
103  *              If the host OS memory managers are initialized, use NULL for
104  *              initial_table_array, and the table will be dynamically allocated.
105  *
106  ******************************************************************************/
107
108 acpi_status __init
109 acpi_initialize_tables(struct acpi_table_desc * initial_table_array,
110                        u32 initial_table_count, u8 allow_resize)
111 {
112         acpi_physical_address rsdp_address;
113         acpi_status status;
114
115         ACPI_FUNCTION_TRACE(acpi_initialize_tables);
116
117         /*
118          * Set up the Root Table Array
119          * Allocate the table array if requested
120          */
121         if (!initial_table_array) {
122                 status = acpi_allocate_root_table(initial_table_count);
123                 if (ACPI_FAILURE(status)) {
124                         return_ACPI_STATUS(status);
125                 }
126         } else {
127                 /* Root Table Array has been statically allocated by the host */
128
129                 ACPI_MEMSET(initial_table_array, 0,
130                             (acpi_size) initial_table_count *
131                             sizeof(struct acpi_table_desc));
132
133                 acpi_gbl_root_table_list.tables = initial_table_array;
134                 acpi_gbl_root_table_list.max_table_count = initial_table_count;
135                 acpi_gbl_root_table_list.flags = ACPI_ROOT_ORIGIN_UNKNOWN;
136                 if (allow_resize) {
137                         acpi_gbl_root_table_list.flags |=
138                             ACPI_ROOT_ALLOW_RESIZE;
139                 }
140         }
141
142         /* Get the address of the RSDP */
143
144         rsdp_address = acpi_os_get_root_pointer();
145         if (!rsdp_address) {
146                 return_ACPI_STATUS(AE_NOT_FOUND);
147         }
148
149         /*
150          * Get the root table (RSDT or XSDT) and extract all entries to the local
151          * Root Table Array. This array contains the information of the RSDT/XSDT
152          * in a common, more useable format.
153          */
154         status = acpi_tb_parse_root_table(rsdp_address);
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         acpi_size current_size;
177
178         ACPI_FUNCTION_TRACE(acpi_reallocate_root_table);
179
180         /*
181          * Only reallocate the root table if the host provided a static buffer
182          * for the table array in the call to acpi_initialize_tables.
183          */
184         if (acpi_gbl_root_table_list.flags & ACPI_ROOT_ORIGIN_ALLOCATED) {
185                 return_ACPI_STATUS(AE_SUPPORT);
186         }
187
188         /*
189          * Get the current size of the root table and add the default
190          * increment to create the new table size.
191          */
192         current_size = (acpi_size)
193             acpi_gbl_root_table_list.current_table_count *
194             sizeof(struct acpi_table_desc);
195
196         new_size = current_size +
197             (ACPI_ROOT_TABLE_SIZE_INCREMENT * sizeof(struct acpi_table_desc));
198
199         /* Create new array and copy the old array */
200
201         tables = ACPI_ALLOCATE_ZEROED(new_size);
202         if (!tables) {
203                 return_ACPI_STATUS(AE_NO_MEMORY);
204         }
205
206         ACPI_MEMCPY(tables, acpi_gbl_root_table_list.tables, current_size);
207
208         /*
209          * Update the root table descriptor. The new size will be the current
210          * number of tables plus the increment, independent of the reserved
211          * size of the original table list.
212          */
213         acpi_gbl_root_table_list.tables = tables;
214         acpi_gbl_root_table_list.max_table_count =
215             acpi_gbl_root_table_list.current_table_count +
216             ACPI_ROOT_TABLE_SIZE_INCREMENT;
217         acpi_gbl_root_table_list.flags =
218             ACPI_ROOT_ORIGIN_ALLOCATED | ACPI_ROOT_ALLOW_RESIZE;
219
220         return_ACPI_STATUS(AE_OK);
221 }
222
223 /*******************************************************************************
224  *
225  * FUNCTION:    acpi_load_table
226  *
227  * PARAMETERS:  table_ptr       - pointer to a buffer containing the entire
228  *                                table to be loaded
229  *
230  * RETURN:      Status
231  *
232  * DESCRIPTION: This function is called to load a table from the caller's
233  *              buffer. The buffer must contain an entire ACPI Table including
234  *              a valid header. The header fields will be verified, and if it
235  *              is determined that the table is invalid, the call will fail.
236  *
237  ******************************************************************************/
238 acpi_status acpi_load_table(struct acpi_table_header *table_ptr)
239 {
240         acpi_status status;
241         u32 table_index;
242         struct acpi_table_desc table_desc;
243
244         if (!table_ptr)
245                 return AE_BAD_PARAMETER;
246
247         ACPI_MEMSET(&table_desc, 0, sizeof(struct acpi_table_desc));
248         table_desc.pointer = table_ptr;
249         table_desc.length = table_ptr->length;
250         table_desc.flags = ACPI_TABLE_ORIGIN_UNKNOWN;
251
252         /*
253          * Install the new table into the local data structures
254          */
255         status = acpi_tb_add_table(&table_desc, &table_index);
256         if (ACPI_FAILURE(status)) {
257                 return status;
258         }
259         status = acpi_ns_load_table(table_index, acpi_gbl_root_node);
260         return status;
261 }
262
263 ACPI_EXPORT_SYMBOL(acpi_load_table)
264
265 /*******************************************************************************
266  *
267  * FUNCTION:    acpi_get_table_header
268  *
269  * PARAMETERS:  Signature           - ACPI signature of needed table
270  *              Instance            - Which instance (for SSDTs)
271  *              out_table_header    - The pointer to the table header to fill
272  *
273  * RETURN:      Status and pointer to mapped table header
274  *
275  * DESCRIPTION: Finds an ACPI table header.
276  *
277  * NOTE:        Caller is responsible in unmapping the header with
278  *              acpi_os_unmap_memory
279  *
280  ******************************************************************************/
281 acpi_status
282 acpi_get_table_header(char *signature,
283                       u32 instance, struct acpi_table_header *out_table_header)
284 {
285        u32 i;
286        u32 j;
287         struct acpi_table_header *header;
288
289         /* Parameter validation */
290
291         if (!signature || !out_table_header) {
292                 return (AE_BAD_PARAMETER);
293         }
294
295         /* Walk the root table list */
296
297         for (i = 0, j = 0; i < acpi_gbl_root_table_list.current_table_count;
298              i++) {
299                 if (!ACPI_COMPARE_NAME
300                     (&(acpi_gbl_root_table_list.tables[i].signature),
301                      signature)) {
302                         continue;
303                 }
304
305                 if (++j < instance) {
306                         continue;
307                 }
308
309                 if (!acpi_gbl_root_table_list.tables[i].pointer) {
310                         if ((acpi_gbl_root_table_list.tables[i].flags &
311                              ACPI_TABLE_ORIGIN_MASK) ==
312                             ACPI_TABLE_ORIGIN_MAPPED) {
313                                 header =
314                                     acpi_os_map_memory(acpi_gbl_root_table_list.
315                                                        tables[i].address,
316                                                        sizeof(struct
317                                                               acpi_table_header));
318                                 if (!header) {
319                                         return AE_NO_MEMORY;
320                                 }
321                                 ACPI_MEMCPY(out_table_header, header,
322                                             sizeof(struct acpi_table_header));
323                                 acpi_os_unmap_memory(header,
324                                                      sizeof(struct
325                                                             acpi_table_header));
326                         } else {
327                                 return AE_NOT_FOUND;
328                         }
329                 } else {
330                         ACPI_MEMCPY(out_table_header,
331                                     acpi_gbl_root_table_list.tables[i].pointer,
332                                     sizeof(struct acpi_table_header));
333                 }
334                 return (AE_OK);
335         }
336
337         return (AE_NOT_FOUND);
338 }
339
340 ACPI_EXPORT_SYMBOL(acpi_get_table_header)
341
342 /*******************************************************************************
343  *
344  * FUNCTION:    acpi_unload_table_id
345  *
346  * PARAMETERS:  id            - Owner ID of the table to be removed.
347  *
348  * RETURN:      Status
349  *
350  * DESCRIPTION: This routine is used to force the unload of a table (by id)
351  *
352  ******************************************************************************/
353 acpi_status acpi_unload_table_id(acpi_owner_id id)
354 {
355         int i;
356         acpi_status status = AE_NOT_EXIST;
357
358         ACPI_FUNCTION_TRACE(acpi_unload_table_id);
359
360         /* Find table in the global table list */
361         for (i = 0; i < acpi_gbl_root_table_list.current_table_count; ++i) {
362                 if (id != acpi_gbl_root_table_list.tables[i].owner_id) {
363                         continue;
364                 }
365                 /*
366                  * Delete all namespace objects owned by this table. Note that these
367                  * objects can appear anywhere in the namespace by virtue of the AML
368                  * "Scope" operator. Thus, we need to track ownership by an ID, not
369                  * simply a position within the hierarchy
370                  */
371                 acpi_tb_delete_namespace_by_owner(i);
372                 status = acpi_tb_release_owner_id(i);
373                 acpi_tb_set_table_loaded_flag(i, FALSE);
374                 break;
375         }
376         return_ACPI_STATUS(status);
377 }
378
379 ACPI_EXPORT_SYMBOL(acpi_unload_table_id)
380
381 /*******************************************************************************
382  *
383  * FUNCTION:    acpi_get_table_with_size
384  *
385  * PARAMETERS:  Signature           - ACPI signature of needed table
386  *              Instance            - Which instance (for SSDTs)
387  *              out_table           - Where the pointer to the table is returned
388  *
389  * RETURN:      Status and pointer to table
390  *
391  * DESCRIPTION: Finds and verifies an ACPI table.
392  *
393  ******************************************************************************/
394 acpi_status
395 acpi_get_table_with_size(char *signature,
396                u32 instance, struct acpi_table_header **out_table,
397                acpi_size *tbl_size)
398 {
399        u32 i;
400        u32 j;
401         acpi_status status;
402
403         /* Parameter validation */
404
405         if (!signature || !out_table) {
406                 return (AE_BAD_PARAMETER);
407         }
408
409         /* Walk the root table list */
410
411         for (i = 0, j = 0; i < acpi_gbl_root_table_list.current_table_count;
412              i++) {
413                 if (!ACPI_COMPARE_NAME
414                     (&(acpi_gbl_root_table_list.tables[i].signature),
415                      signature)) {
416                         continue;
417                 }
418
419                 if (++j < instance) {
420                         continue;
421                 }
422
423                 status =
424                     acpi_tb_verify_table(&acpi_gbl_root_table_list.tables[i]);
425                 if (ACPI_SUCCESS(status)) {
426                         *out_table = acpi_gbl_root_table_list.tables[i].pointer;
427                         *tbl_size = acpi_gbl_root_table_list.tables[i].length;
428                 }
429
430                 if (!acpi_gbl_permanent_mmap) {
431                         acpi_gbl_root_table_list.tables[i].pointer = NULL;
432                 }
433
434                 return (status);
435         }
436
437         return (AE_NOT_FOUND);
438 }
439 ACPI_EXPORT_SYMBOL(acpi_get_table_with_size)
440
441 acpi_status
442 acpi_get_table(char *signature,
443                u32 instance, struct acpi_table_header **out_table)
444 {
445         acpi_size tbl_size;
446
447         return acpi_get_table_with_size(signature,
448                        instance, out_table, &tbl_size);
449 }
450 ACPI_EXPORT_SYMBOL(acpi_get_table)
451
452 /*******************************************************************************
453  *
454  * FUNCTION:    acpi_get_table_by_index
455  *
456  * PARAMETERS:  table_index         - Table index
457  *              Table               - Where the pointer to the table is returned
458  *
459  * RETURN:      Status and pointer to the table
460  *
461  * DESCRIPTION: Obtain a table by an index into the global table list.
462  *
463  ******************************************************************************/
464 acpi_status
465 acpi_get_table_by_index(u32 table_index, struct acpi_table_header **table)
466 {
467         acpi_status status;
468
469         ACPI_FUNCTION_TRACE(acpi_get_table_by_index);
470
471         /* Parameter validation */
472
473         if (!table) {
474                 return_ACPI_STATUS(AE_BAD_PARAMETER);
475         }
476
477         (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
478
479         /* Validate index */
480
481         if (table_index >= acpi_gbl_root_table_list.current_table_count) {
482                 (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
483                 return_ACPI_STATUS(AE_BAD_PARAMETER);
484         }
485
486         if (!acpi_gbl_root_table_list.tables[table_index].pointer) {
487
488                 /* Table is not mapped, map it */
489
490                 status =
491                     acpi_tb_verify_table(&acpi_gbl_root_table_list.
492                                          tables[table_index]);
493                 if (ACPI_FAILURE(status)) {
494                         (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
495                         return_ACPI_STATUS(status);
496                 }
497         }
498
499         *table = acpi_gbl_root_table_list.tables[table_index].pointer;
500         (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
501         return_ACPI_STATUS(AE_OK);
502 }
503
504 ACPI_EXPORT_SYMBOL(acpi_get_table_by_index)
505
506 /*******************************************************************************
507  *
508  * FUNCTION:    acpi_tb_load_namespace
509  *
510  * PARAMETERS:  None
511  *
512  * RETURN:      Status
513  *
514  * DESCRIPTION: Load the namespace from the DSDT and all SSDTs/PSDTs found in
515  *              the RSDT/XSDT.
516  *
517  ******************************************************************************/
518 static acpi_status acpi_tb_load_namespace(void)
519 {
520         acpi_status status;
521         u32 i;
522         struct acpi_table_header *new_dsdt;
523
524         ACPI_FUNCTION_TRACE(tb_load_namespace);
525
526         (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
527
528         /*
529          * Load the namespace. The DSDT is required, but any SSDT and
530          * PSDT tables are optional. Verify the DSDT.
531          */
532         if (!acpi_gbl_root_table_list.current_table_count ||
533             !ACPI_COMPARE_NAME(&
534                                (acpi_gbl_root_table_list.
535                                 tables[ACPI_TABLE_INDEX_DSDT].signature),
536                                ACPI_SIG_DSDT)
537             ||
538             ACPI_FAILURE(acpi_tb_verify_table
539                          (&acpi_gbl_root_table_list.
540                           tables[ACPI_TABLE_INDEX_DSDT]))) {
541                 status = AE_NO_ACPI_TABLES;
542                 goto unlock_and_exit;
543         }
544
545         /*
546          * Save the DSDT pointer for simple access. This is the mapped memory
547          * address. We must take care here because the address of the .Tables
548          * array can change dynamically as tables are loaded at run-time. Note:
549          * .Pointer field is not validated until after call to acpi_tb_verify_table.
550          */
551         acpi_gbl_DSDT =
552             acpi_gbl_root_table_list.tables[ACPI_TABLE_INDEX_DSDT].pointer;
553
554         /*
555          * Optionally copy the entire DSDT to local memory (instead of simply
556          * mapping it.) There are some BIOSs that corrupt or replace the original
557          * DSDT, creating the need for this option. Default is FALSE, do not copy
558          * the DSDT.
559          */
560         if (acpi_gbl_copy_dsdt_locally) {
561                 new_dsdt = acpi_tb_copy_dsdt(ACPI_TABLE_INDEX_DSDT);
562                 if (new_dsdt) {
563                         acpi_gbl_DSDT = new_dsdt;
564                 }
565         }
566
567         /*
568          * Save the original DSDT header for detection of table corruption
569          * and/or replacement of the DSDT from outside the OS.
570          */
571         ACPI_MEMCPY(&acpi_gbl_original_dsdt_header, acpi_gbl_DSDT,
572                     sizeof(struct acpi_table_header));
573
574         (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
575
576         /* Load and parse tables */
577
578         status = acpi_ns_load_table(ACPI_TABLE_INDEX_DSDT, acpi_gbl_root_node);
579         if (ACPI_FAILURE(status)) {
580                 return_ACPI_STATUS(status);
581         }
582
583         /* Load any SSDT or PSDT tables. Note: Loop leaves tables locked */
584
585         (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
586         for (i = 0; i < acpi_gbl_root_table_list.current_table_count; ++i) {
587                 if ((!ACPI_COMPARE_NAME
588                      (&(acpi_gbl_root_table_list.tables[i].signature),
589                       ACPI_SIG_SSDT)
590                      &&
591                      !ACPI_COMPARE_NAME(&
592                                         (acpi_gbl_root_table_list.tables[i].
593                                          signature), ACPI_SIG_PSDT))
594                     ||
595                     ACPI_FAILURE(acpi_tb_verify_table
596                                  (&acpi_gbl_root_table_list.tables[i]))) {
597                         continue;
598                 }
599
600                 if (no_auto_ssdt) {
601                         printk(KERN_WARNING "ACPI: SSDT ignored due to \"acpi_no_auto_ssdt\"\n");
602                         continue;
603                 }
604
605                 /* Ignore errors while loading tables, get as many as possible */
606
607                 (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
608                 (void)acpi_ns_load_table(i, acpi_gbl_root_node);
609                 (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
610         }
611
612         ACPI_DEBUG_PRINT((ACPI_DB_INIT, "ACPI Tables successfully acquired\n"));
613
614       unlock_and_exit:
615         (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
616         return_ACPI_STATUS(status);
617 }
618
619 /*******************************************************************************
620  *
621  * FUNCTION:    acpi_load_tables
622  *
623  * PARAMETERS:  None
624  *
625  * RETURN:      Status
626  *
627  * DESCRIPTION: Load the ACPI tables from the RSDT/XSDT
628  *
629  ******************************************************************************/
630
631 acpi_status acpi_load_tables(void)
632 {
633         acpi_status status;
634
635         ACPI_FUNCTION_TRACE(acpi_load_tables);
636
637         /* Load the namespace from the tables */
638
639         status = acpi_tb_load_namespace();
640         if (ACPI_FAILURE(status)) {
641                 ACPI_EXCEPTION((AE_INFO, status,
642                                 "While loading namespace from ACPI tables"));
643         }
644
645         return_ACPI_STATUS(status);
646 }
647
648 ACPI_EXPORT_SYMBOL(acpi_load_tables)
649
650
651 /*******************************************************************************
652  *
653  * FUNCTION:    acpi_install_table_handler
654  *
655  * PARAMETERS:  Handler         - Table event handler
656  *              Context         - Value passed to the handler on each event
657  *
658  * RETURN:      Status
659  *
660  * DESCRIPTION: Install table event handler
661  *
662  ******************************************************************************/
663 acpi_status
664 acpi_install_table_handler(acpi_tbl_handler handler, void *context)
665 {
666         acpi_status status;
667
668         ACPI_FUNCTION_TRACE(acpi_install_table_handler);
669
670         if (!handler) {
671                 return_ACPI_STATUS(AE_BAD_PARAMETER);
672         }
673
674         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
675         if (ACPI_FAILURE(status)) {
676                 return_ACPI_STATUS(status);
677         }
678
679         /* Don't allow more than one handler */
680
681         if (acpi_gbl_table_handler) {
682                 status = AE_ALREADY_EXISTS;
683                 goto cleanup;
684         }
685
686         /* Install the handler */
687
688         acpi_gbl_table_handler = handler;
689         acpi_gbl_table_handler_context = context;
690
691       cleanup:
692         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
693         return_ACPI_STATUS(status);
694 }
695
696 ACPI_EXPORT_SYMBOL(acpi_install_table_handler)
697
698 /*******************************************************************************
699  *
700  * FUNCTION:    acpi_remove_table_handler
701  *
702  * PARAMETERS:  Handler         - Table event handler that was installed
703  *                                previously.
704  *
705  * RETURN:      Status
706  *
707  * DESCRIPTION: Remove table event handler
708  *
709  ******************************************************************************/
710 acpi_status acpi_remove_table_handler(acpi_tbl_handler handler)
711 {
712         acpi_status status;
713
714         ACPI_FUNCTION_TRACE(acpi_remove_table_handler);
715
716         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
717         if (ACPI_FAILURE(status)) {
718                 return_ACPI_STATUS(status);
719         }
720
721         /* Make sure that the installed handler is the same */
722
723         if (!handler || handler != acpi_gbl_table_handler) {
724                 status = AE_BAD_PARAMETER;
725                 goto cleanup;
726         }
727
728         /* Remove the handler */
729
730         acpi_gbl_table_handler = NULL;
731
732       cleanup:
733         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
734         return_ACPI_STATUS(status);
735 }
736
737 ACPI_EXPORT_SYMBOL(acpi_remove_table_handler)
738
739
740 static int __init acpi_no_auto_ssdt_setup(char *s) {
741
742         printk(KERN_NOTICE "ACPI: SSDT auto-load disabled\n");
743
744         no_auto_ssdt = 1;
745
746         return 1;
747 }
748
749 __setup("acpi_no_auto_ssdt", acpi_no_auto_ssdt_setup);