ACPICA: hide private headers
[linux-2.6.git] / drivers / acpi / acpica / evxface.c
1 /******************************************************************************
2  *
3  * Module Name: evxface - External interfaces for ACPI events
4  *
5  *****************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2008, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43
44 #include <acpi/acpi.h>
45 #include "accommon.h"
46 #include "acnamesp.h"
47 #include "acevents.h"
48 #include "acinterp.h"
49
50 #define _COMPONENT          ACPI_EVENTS
51 ACPI_MODULE_NAME("evxface")
52
53 /*******************************************************************************
54  *
55  * FUNCTION:    acpi_install_exception_handler
56  *
57  * PARAMETERS:  Handler         - Pointer to the handler function for the
58  *                                event
59  *
60  * RETURN:      Status
61  *
62  * DESCRIPTION: Saves the pointer to the handler function
63  *
64  ******************************************************************************/
65 #ifdef ACPI_FUTURE_USAGE
66 acpi_status acpi_install_exception_handler(acpi_exception_handler handler)
67 {
68         acpi_status status;
69
70         ACPI_FUNCTION_TRACE(acpi_install_exception_handler);
71
72         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
73         if (ACPI_FAILURE(status)) {
74                 return_ACPI_STATUS(status);
75         }
76
77         /* Don't allow two handlers. */
78
79         if (acpi_gbl_exception_handler) {
80                 status = AE_ALREADY_EXISTS;
81                 goto cleanup;
82         }
83
84         /* Install the handler */
85
86         acpi_gbl_exception_handler = handler;
87
88       cleanup:
89         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
90         return_ACPI_STATUS(status);
91 }
92
93 ACPI_EXPORT_SYMBOL(acpi_install_exception_handler)
94 #endif                          /*  ACPI_FUTURE_USAGE  */
95 /*******************************************************************************
96  *
97  * FUNCTION:    acpi_install_fixed_event_handler
98  *
99  * PARAMETERS:  Event           - Event type to enable.
100  *              Handler         - Pointer to the handler function for the
101  *                                event
102  *              Context         - Value passed to the handler on each GPE
103  *
104  * RETURN:      Status
105  *
106  * DESCRIPTION: Saves the pointer to the handler function and then enables the
107  *              event.
108  *
109  ******************************************************************************/
110 acpi_status
111 acpi_install_fixed_event_handler(u32 event,
112                                  acpi_event_handler handler, void *context)
113 {
114         acpi_status status;
115
116         ACPI_FUNCTION_TRACE(acpi_install_fixed_event_handler);
117
118         /* Parameter validation */
119
120         if (event > ACPI_EVENT_MAX) {
121                 return_ACPI_STATUS(AE_BAD_PARAMETER);
122         }
123
124         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
125         if (ACPI_FAILURE(status)) {
126                 return_ACPI_STATUS(status);
127         }
128
129         /* Don't allow two handlers. */
130
131         if (NULL != acpi_gbl_fixed_event_handlers[event].handler) {
132                 status = AE_ALREADY_EXISTS;
133                 goto cleanup;
134         }
135
136         /* Install the handler before enabling the event */
137
138         acpi_gbl_fixed_event_handlers[event].handler = handler;
139         acpi_gbl_fixed_event_handlers[event].context = context;
140
141         status = acpi_clear_event(event);
142         if (ACPI_SUCCESS(status))
143                 status = acpi_enable_event(event, 0);
144         if (ACPI_FAILURE(status)) {
145                 ACPI_WARNING((AE_INFO, "Could not enable fixed event %X",
146                               event));
147
148                 /* Remove the handler */
149
150                 acpi_gbl_fixed_event_handlers[event].handler = NULL;
151                 acpi_gbl_fixed_event_handlers[event].context = NULL;
152         } else {
153                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
154                                   "Enabled fixed event %X, Handler=%p\n", event,
155                                   handler));
156         }
157
158       cleanup:
159         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
160         return_ACPI_STATUS(status);
161 }
162
163 ACPI_EXPORT_SYMBOL(acpi_install_fixed_event_handler)
164
165 /*******************************************************************************
166  *
167  * FUNCTION:    acpi_remove_fixed_event_handler
168  *
169  * PARAMETERS:  Event           - Event type to disable.
170  *              Handler         - Address of the handler
171  *
172  * RETURN:      Status
173  *
174  * DESCRIPTION: Disables the event and unregisters the event handler.
175  *
176  ******************************************************************************/
177 acpi_status
178 acpi_remove_fixed_event_handler(u32 event, acpi_event_handler handler)
179 {
180         acpi_status status = AE_OK;
181
182         ACPI_FUNCTION_TRACE(acpi_remove_fixed_event_handler);
183
184         /* Parameter validation */
185
186         if (event > ACPI_EVENT_MAX) {
187                 return_ACPI_STATUS(AE_BAD_PARAMETER);
188         }
189
190         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
191         if (ACPI_FAILURE(status)) {
192                 return_ACPI_STATUS(status);
193         }
194
195         /* Disable the event before removing the handler */
196
197         status = acpi_disable_event(event, 0);
198
199         /* Always Remove the handler */
200
201         acpi_gbl_fixed_event_handlers[event].handler = NULL;
202         acpi_gbl_fixed_event_handlers[event].context = NULL;
203
204         if (ACPI_FAILURE(status)) {
205                 ACPI_WARNING((AE_INFO,
206                               "Could not write to fixed event enable register %X",
207                               event));
208         } else {
209                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Disabled fixed event %X\n",
210                                   event));
211         }
212
213         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
214         return_ACPI_STATUS(status);
215 }
216
217 ACPI_EXPORT_SYMBOL(acpi_remove_fixed_event_handler)
218
219 /*******************************************************************************
220  *
221  * FUNCTION:    acpi_install_notify_handler
222  *
223  * PARAMETERS:  Device          - The device for which notifies will be handled
224  *              handler_type    - The type of handler:
225  *                                  ACPI_SYSTEM_NOTIFY: system_handler (00-7f)
226  *                                  ACPI_DEVICE_NOTIFY: driver_handler (80-ff)
227  *                                  ACPI_ALL_NOTIFY:  both system and device
228  *              Handler         - Address of the handler
229  *              Context         - Value passed to the handler on each GPE
230  *
231  * RETURN:      Status
232  *
233  * DESCRIPTION: Install a handler for notifies on an ACPI device
234  *
235  ******************************************************************************/
236 acpi_status
237 acpi_install_notify_handler(acpi_handle device,
238                             u32 handler_type,
239                             acpi_notify_handler handler, void *context)
240 {
241         union acpi_operand_object *obj_desc;
242         union acpi_operand_object *notify_obj;
243         struct acpi_namespace_node *node;
244         acpi_status status;
245
246         ACPI_FUNCTION_TRACE(acpi_install_notify_handler);
247
248         /* Parameter validation */
249
250         if ((!device) ||
251             (!handler) || (handler_type > ACPI_MAX_NOTIFY_HANDLER_TYPE)) {
252                 return_ACPI_STATUS(AE_BAD_PARAMETER);
253         }
254
255         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
256         if (ACPI_FAILURE(status)) {
257                 return_ACPI_STATUS(status);
258         }
259
260         /* Convert and validate the device handle */
261
262         node = acpi_ns_map_handle_to_node(device);
263         if (!node) {
264                 status = AE_BAD_PARAMETER;
265                 goto unlock_and_exit;
266         }
267
268         /*
269          * Root Object:
270          * Registering a notify handler on the root object indicates that the
271          * caller wishes to receive notifications for all objects. Note that
272          * only one <external> global handler can be regsitered (per notify type).
273          */
274         if (device == ACPI_ROOT_OBJECT) {
275
276                 /* Make sure the handler is not already installed */
277
278                 if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
279                      acpi_gbl_system_notify.handler) ||
280                     ((handler_type & ACPI_DEVICE_NOTIFY) &&
281                      acpi_gbl_device_notify.handler)) {
282                         status = AE_ALREADY_EXISTS;
283                         goto unlock_and_exit;
284                 }
285
286                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
287                         acpi_gbl_system_notify.node = node;
288                         acpi_gbl_system_notify.handler = handler;
289                         acpi_gbl_system_notify.context = context;
290                 }
291
292                 if (handler_type & ACPI_DEVICE_NOTIFY) {
293                         acpi_gbl_device_notify.node = node;
294                         acpi_gbl_device_notify.handler = handler;
295                         acpi_gbl_device_notify.context = context;
296                 }
297
298                 /* Global notify handler installed */
299         }
300
301         /*
302          * All Other Objects:
303          * Caller will only receive notifications specific to the target object.
304          * Note that only certain object types can receive notifications.
305          */
306         else {
307                 /* Notifies allowed on this object? */
308
309                 if (!acpi_ev_is_notify_object(node)) {
310                         status = AE_TYPE;
311                         goto unlock_and_exit;
312                 }
313
314                 /* Check for an existing internal object */
315
316                 obj_desc = acpi_ns_get_attached_object(node);
317                 if (obj_desc) {
318
319                         /* Object exists - make sure there's no handler */
320
321                         if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
322                              obj_desc->common_notify.system_notify) ||
323                             ((handler_type & ACPI_DEVICE_NOTIFY) &&
324                              obj_desc->common_notify.device_notify)) {
325                                 status = AE_ALREADY_EXISTS;
326                                 goto unlock_and_exit;
327                         }
328                 } else {
329                         /* Create a new object */
330
331                         obj_desc = acpi_ut_create_internal_object(node->type);
332                         if (!obj_desc) {
333                                 status = AE_NO_MEMORY;
334                                 goto unlock_and_exit;
335                         }
336
337                         /* Attach new object to the Node */
338
339                         status =
340                             acpi_ns_attach_object(device, obj_desc, node->type);
341
342                         /* Remove local reference to the object */
343
344                         acpi_ut_remove_reference(obj_desc);
345                         if (ACPI_FAILURE(status)) {
346                                 goto unlock_and_exit;
347                         }
348                 }
349
350                 /* Install the handler */
351
352                 notify_obj =
353                     acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_NOTIFY);
354                 if (!notify_obj) {
355                         status = AE_NO_MEMORY;
356                         goto unlock_and_exit;
357                 }
358
359                 notify_obj->notify.node = node;
360                 notify_obj->notify.handler = handler;
361                 notify_obj->notify.context = context;
362
363                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
364                         obj_desc->common_notify.system_notify = notify_obj;
365                 }
366
367                 if (handler_type & ACPI_DEVICE_NOTIFY) {
368                         obj_desc->common_notify.device_notify = notify_obj;
369                 }
370
371                 if (handler_type == ACPI_ALL_NOTIFY) {
372
373                         /* Extra ref if installed in both */
374
375                         acpi_ut_add_reference(notify_obj);
376                 }
377         }
378
379       unlock_and_exit:
380         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
381         return_ACPI_STATUS(status);
382 }
383
384 ACPI_EXPORT_SYMBOL(acpi_install_notify_handler)
385
386 /*******************************************************************************
387  *
388  * FUNCTION:    acpi_remove_notify_handler
389  *
390  * PARAMETERS:  Device          - The device for which notifies will be handled
391  *              handler_type    - The type of handler:
392  *                                  ACPI_SYSTEM_NOTIFY: system_handler (00-7f)
393  *                                  ACPI_DEVICE_NOTIFY: driver_handler (80-ff)
394  *                                  ACPI_ALL_NOTIFY:  both system and device
395  *              Handler         - Address of the handler
396  *
397  * RETURN:      Status
398  *
399  * DESCRIPTION: Remove a handler for notifies on an ACPI device
400  *
401  ******************************************************************************/
402 acpi_status
403 acpi_remove_notify_handler(acpi_handle device,
404                            u32 handler_type, acpi_notify_handler handler)
405 {
406         union acpi_operand_object *notify_obj;
407         union acpi_operand_object *obj_desc;
408         struct acpi_namespace_node *node;
409         acpi_status status;
410
411         ACPI_FUNCTION_TRACE(acpi_remove_notify_handler);
412
413         /* Parameter validation */
414
415         if ((!device) ||
416             (!handler) || (handler_type > ACPI_MAX_NOTIFY_HANDLER_TYPE)) {
417                 status = AE_BAD_PARAMETER;
418                 goto exit;
419         }
420
421         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
422         if (ACPI_FAILURE(status)) {
423                 goto exit;
424         }
425
426         /* Convert and validate the device handle */
427
428         node = acpi_ns_map_handle_to_node(device);
429         if (!node) {
430                 status = AE_BAD_PARAMETER;
431                 goto unlock_and_exit;
432         }
433
434         /* Root Object */
435
436         if (device == ACPI_ROOT_OBJECT) {
437                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
438                                   "Removing notify handler for namespace root object\n"));
439
440                 if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
441                      !acpi_gbl_system_notify.handler) ||
442                     ((handler_type & ACPI_DEVICE_NOTIFY) &&
443                      !acpi_gbl_device_notify.handler)) {
444                         status = AE_NOT_EXIST;
445                         goto unlock_and_exit;
446                 }
447
448                 /* Make sure all deferred tasks are completed */
449
450                 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
451                 acpi_os_wait_events_complete(NULL);
452                 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
453                 if (ACPI_FAILURE(status)) {
454                         goto exit;
455                 }
456
457                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
458                         acpi_gbl_system_notify.node = NULL;
459                         acpi_gbl_system_notify.handler = NULL;
460                         acpi_gbl_system_notify.context = NULL;
461                 }
462
463                 if (handler_type & ACPI_DEVICE_NOTIFY) {
464                         acpi_gbl_device_notify.node = NULL;
465                         acpi_gbl_device_notify.handler = NULL;
466                         acpi_gbl_device_notify.context = NULL;
467                 }
468         }
469
470         /* All Other Objects */
471
472         else {
473                 /* Notifies allowed on this object? */
474
475                 if (!acpi_ev_is_notify_object(node)) {
476                         status = AE_TYPE;
477                         goto unlock_and_exit;
478                 }
479
480                 /* Check for an existing internal object */
481
482                 obj_desc = acpi_ns_get_attached_object(node);
483                 if (!obj_desc) {
484                         status = AE_NOT_EXIST;
485                         goto unlock_and_exit;
486                 }
487
488                 /* Object exists - make sure there's an existing handler */
489
490                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
491                         notify_obj = obj_desc->common_notify.system_notify;
492                         if (!notify_obj) {
493                                 status = AE_NOT_EXIST;
494                                 goto unlock_and_exit;
495                         }
496
497                         if (notify_obj->notify.handler != handler) {
498                                 status = AE_BAD_PARAMETER;
499                                 goto unlock_and_exit;
500                         }
501                         /* Make sure all deferred tasks are completed */
502
503                         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
504                         acpi_os_wait_events_complete(NULL);
505                         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
506                         if (ACPI_FAILURE(status)) {
507                                 goto exit;
508                         }
509
510                         /* Remove the handler */
511                         obj_desc->common_notify.system_notify = NULL;
512                         acpi_ut_remove_reference(notify_obj);
513                 }
514
515                 if (handler_type & ACPI_DEVICE_NOTIFY) {
516                         notify_obj = obj_desc->common_notify.device_notify;
517                         if (!notify_obj) {
518                                 status = AE_NOT_EXIST;
519                                 goto unlock_and_exit;
520                         }
521
522                         if (notify_obj->notify.handler != handler) {
523                                 status = AE_BAD_PARAMETER;
524                                 goto unlock_and_exit;
525                         }
526                         /* Make sure all deferred tasks are completed */
527
528                         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
529                         acpi_os_wait_events_complete(NULL);
530                         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
531                         if (ACPI_FAILURE(status)) {
532                                 goto exit;
533                         }
534
535                         /* Remove the handler */
536                         obj_desc->common_notify.device_notify = NULL;
537                         acpi_ut_remove_reference(notify_obj);
538                 }
539         }
540
541       unlock_and_exit:
542         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
543       exit:
544         if (ACPI_FAILURE(status))
545                 ACPI_EXCEPTION((AE_INFO, status, "Removing notify handler"));
546         return_ACPI_STATUS(status);
547 }
548
549 ACPI_EXPORT_SYMBOL(acpi_remove_notify_handler)
550
551 /*******************************************************************************
552  *
553  * FUNCTION:    acpi_install_gpe_handler
554  *
555  * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
556  *                                defined GPEs)
557  *              gpe_number      - The GPE number within the GPE block
558  *              Type            - Whether this GPE should be treated as an
559  *                                edge- or level-triggered interrupt.
560  *              Address         - Address of the handler
561  *              Context         - Value passed to the handler on each GPE
562  *
563  * RETURN:      Status
564  *
565  * DESCRIPTION: Install a handler for a General Purpose Event.
566  *
567  ******************************************************************************/
568 acpi_status
569 acpi_install_gpe_handler(acpi_handle gpe_device,
570                          u32 gpe_number,
571                          u32 type, acpi_event_handler address, void *context)
572 {
573         struct acpi_gpe_event_info *gpe_event_info;
574         struct acpi_handler_info *handler;
575         acpi_status status;
576         acpi_cpu_flags flags;
577
578         ACPI_FUNCTION_TRACE(acpi_install_gpe_handler);
579
580         /* Parameter validation */
581
582         if ((!address) || (type > ACPI_GPE_XRUPT_TYPE_MASK)) {
583                 status = AE_BAD_PARAMETER;
584                 goto exit;
585         }
586
587         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
588         if (ACPI_FAILURE(status)) {
589                 goto exit;
590         }
591
592         /* Ensure that we have a valid GPE number */
593
594         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
595         if (!gpe_event_info) {
596                 status = AE_BAD_PARAMETER;
597                 goto unlock_and_exit;
598         }
599
600         /* Make sure that there isn't a handler there already */
601
602         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
603             ACPI_GPE_DISPATCH_HANDLER) {
604                 status = AE_ALREADY_EXISTS;
605                 goto unlock_and_exit;
606         }
607
608         /* Allocate and init handler object */
609
610         handler = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_handler_info));
611         if (!handler) {
612                 status = AE_NO_MEMORY;
613                 goto unlock_and_exit;
614         }
615
616         handler->address = address;
617         handler->context = context;
618         handler->method_node = gpe_event_info->dispatch.method_node;
619
620         /* Disable the GPE before installing the handler */
621
622         status = acpi_ev_disable_gpe(gpe_event_info);
623         if (ACPI_FAILURE(status)) {
624                 goto unlock_and_exit;
625         }
626
627         /* Install the handler */
628
629         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
630         gpe_event_info->dispatch.handler = handler;
631
632         /* Setup up dispatch flags to indicate handler (vs. method) */
633
634         gpe_event_info->flags &= ~(ACPI_GPE_XRUPT_TYPE_MASK | ACPI_GPE_DISPATCH_MASK);  /* Clear bits */
635         gpe_event_info->flags |= (u8) (type | ACPI_GPE_DISPATCH_HANDLER);
636
637         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
638
639       unlock_and_exit:
640         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
641       exit:
642         if (ACPI_FAILURE(status))
643                 ACPI_EXCEPTION((AE_INFO, status,
644                                 "Installing notify handler failed"));
645         return_ACPI_STATUS(status);
646 }
647
648 ACPI_EXPORT_SYMBOL(acpi_install_gpe_handler)
649
650 /*******************************************************************************
651  *
652  * FUNCTION:    acpi_remove_gpe_handler
653  *
654  * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
655  *                                defined GPEs)
656  *              gpe_number      - The event to remove a handler
657  *              Address         - Address of the handler
658  *
659  * RETURN:      Status
660  *
661  * DESCRIPTION: Remove a handler for a General Purpose acpi_event.
662  *
663  ******************************************************************************/
664 acpi_status
665 acpi_remove_gpe_handler(acpi_handle gpe_device,
666                         u32 gpe_number, acpi_event_handler address)
667 {
668         struct acpi_gpe_event_info *gpe_event_info;
669         struct acpi_handler_info *handler;
670         acpi_status status;
671         acpi_cpu_flags flags;
672
673         ACPI_FUNCTION_TRACE(acpi_remove_gpe_handler);
674
675         /* Parameter validation */
676
677         if (!address) {
678                 return_ACPI_STATUS(AE_BAD_PARAMETER);
679         }
680
681         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
682         if (ACPI_FAILURE(status)) {
683                 return_ACPI_STATUS(status);
684         }
685
686         /* Ensure that we have a valid GPE number */
687
688         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
689         if (!gpe_event_info) {
690                 status = AE_BAD_PARAMETER;
691                 goto unlock_and_exit;
692         }
693
694         /* Make sure that a handler is indeed installed */
695
696         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) !=
697             ACPI_GPE_DISPATCH_HANDLER) {
698                 status = AE_NOT_EXIST;
699                 goto unlock_and_exit;
700         }
701
702         /* Make sure that the installed handler is the same */
703
704         if (gpe_event_info->dispatch.handler->address != address) {
705                 status = AE_BAD_PARAMETER;
706                 goto unlock_and_exit;
707         }
708
709         /* Disable the GPE before removing the handler */
710
711         status = acpi_ev_disable_gpe(gpe_event_info);
712         if (ACPI_FAILURE(status)) {
713                 goto unlock_and_exit;
714         }
715
716         /* Make sure all deferred tasks are completed */
717
718         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
719         acpi_os_wait_events_complete(NULL);
720         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
721         if (ACPI_FAILURE(status)) {
722                 return_ACPI_STATUS(status);
723         }
724
725         /* Remove the handler */
726
727         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
728         handler = gpe_event_info->dispatch.handler;
729
730         /* Restore Method node (if any), set dispatch flags */
731
732         gpe_event_info->dispatch.method_node = handler->method_node;
733         gpe_event_info->flags &= ~ACPI_GPE_DISPATCH_MASK;       /* Clear bits */
734         if (handler->method_node) {
735                 gpe_event_info->flags |= ACPI_GPE_DISPATCH_METHOD;
736         }
737         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
738
739         /* Now we can free the handler object */
740
741         ACPI_FREE(handler);
742
743       unlock_and_exit:
744         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
745         return_ACPI_STATUS(status);
746 }
747
748 ACPI_EXPORT_SYMBOL(acpi_remove_gpe_handler)
749
750 /*******************************************************************************
751  *
752  * FUNCTION:    acpi_acquire_global_lock
753  *
754  * PARAMETERS:  Timeout         - How long the caller is willing to wait
755  *              Handle          - Where the handle to the lock is returned
756  *                                (if acquired)
757  *
758  * RETURN:      Status
759  *
760  * DESCRIPTION: Acquire the ACPI Global Lock
761  *
762  * Note: Allows callers with the same thread ID to acquire the global lock
763  * multiple times. In other words, externally, the behavior of the global lock
764  * is identical to an AML mutex. On the first acquire, a new handle is
765  * returned. On any subsequent calls to acquire by the same thread, the same
766  * handle is returned.
767  *
768  ******************************************************************************/
769 acpi_status acpi_acquire_global_lock(u16 timeout, u32 * handle)
770 {
771         acpi_status status;
772
773         if (!handle) {
774                 return (AE_BAD_PARAMETER);
775         }
776
777         /* Must lock interpreter to prevent race conditions */
778
779         acpi_ex_enter_interpreter();
780
781         status = acpi_ex_acquire_mutex_object(timeout,
782                                               acpi_gbl_global_lock_mutex,
783                                               acpi_os_get_thread_id());
784
785         if (ACPI_SUCCESS(status)) {
786
787                 /* Return the global lock handle (updated in acpi_ev_acquire_global_lock) */
788
789                 *handle = acpi_gbl_global_lock_handle;
790         }
791
792         acpi_ex_exit_interpreter();
793         return (status);
794 }
795
796 ACPI_EXPORT_SYMBOL(acpi_acquire_global_lock)
797
798 /*******************************************************************************
799  *
800  * FUNCTION:    acpi_release_global_lock
801  *
802  * PARAMETERS:  Handle      - Returned from acpi_acquire_global_lock
803  *
804  * RETURN:      Status
805  *
806  * DESCRIPTION: Release the ACPI Global Lock. The handle must be valid.
807  *
808  ******************************************************************************/
809 acpi_status acpi_release_global_lock(u32 handle)
810 {
811         acpi_status status;
812
813         if (!handle || (handle != acpi_gbl_global_lock_handle)) {
814                 return (AE_NOT_ACQUIRED);
815         }
816
817         status = acpi_ex_release_mutex_object(acpi_gbl_global_lock_mutex);
818         return (status);
819 }
820
821 ACPI_EXPORT_SYMBOL(acpi_release_global_lock)