Pull acpica into release branch
[pandora-kernel.git] / drivers / acpi / events / evxface.c
1 /******************************************************************************
2  *
3  * Module Name: evxface - External interfaces for ACPI events
4  *
5  *****************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2006, R. Byron Moore
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 <acpi/acnamesp.h>
46 #include <acpi/acevents.h>
47 #include <acpi/acinterp.h>
48
49 #define _COMPONENT          ACPI_EVENTS
50 ACPI_MODULE_NAME("evxface")
51
52 /*******************************************************************************
53  *
54  * FUNCTION:    acpi_install_exception_handler
55  *
56  * PARAMETERS:  Handler         - Pointer to the handler function for the
57  *                                event
58  *
59  * RETURN:      Status
60  *
61  * DESCRIPTION: Saves the pointer to the handler function
62  *
63  ******************************************************************************/
64 #ifdef ACPI_FUTURE_USAGE
65 acpi_status acpi_install_exception_handler(acpi_exception_handler handler)
66 {
67         acpi_status status;
68
69         ACPI_FUNCTION_TRACE(acpi_install_exception_handler);
70
71         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
72         if (ACPI_FAILURE(status)) {
73                 return_ACPI_STATUS(status);
74         }
75
76         /* Don't allow two handlers. */
77
78         if (acpi_gbl_exception_handler) {
79                 status = AE_ALREADY_EXISTS;
80                 goto cleanup;
81         }
82
83         /* Install the handler */
84
85         acpi_gbl_exception_handler = handler;
86
87       cleanup:
88         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
89         return_ACPI_STATUS(status);
90 }
91
92 ACPI_EXPORT_SYMBOL(acpi_install_exception_handler)
93 #endif                          /*  ACPI_FUTURE_USAGE  */
94
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                 return_ACPI_STATUS(AE_BAD_PARAMETER);
418         }
419
420         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
421         if (ACPI_FAILURE(status)) {
422                 return_ACPI_STATUS(status);
423         }
424
425         /* Convert and validate the device handle */
426
427         node = acpi_ns_map_handle_to_node(device);
428         if (!node) {
429                 status = AE_BAD_PARAMETER;
430                 goto unlock_and_exit;
431         }
432
433         /* Root Object */
434
435         if (device == ACPI_ROOT_OBJECT) {
436                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
437                                   "Removing notify handler for namespace root object\n"));
438
439                 if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
440                      !acpi_gbl_system_notify.handler) ||
441                     ((handler_type & ACPI_DEVICE_NOTIFY) &&
442                      !acpi_gbl_device_notify.handler)) {
443                         status = AE_NOT_EXIST;
444                         goto unlock_and_exit;
445                 }
446
447                 /* Make sure all deferred tasks are completed */
448
449                 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
450                 acpi_os_wait_events_complete(NULL);
451                 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
452                 if (ACPI_FAILURE(status)) {
453                         return_ACPI_STATUS(status);
454                 }
455
456                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
457                         acpi_gbl_system_notify.node = NULL;
458                         acpi_gbl_system_notify.handler = NULL;
459                         acpi_gbl_system_notify.context = NULL;
460                 }
461
462                 if (handler_type & ACPI_DEVICE_NOTIFY) {
463                         acpi_gbl_device_notify.node = NULL;
464                         acpi_gbl_device_notify.handler = NULL;
465                         acpi_gbl_device_notify.context = NULL;
466                 }
467         }
468
469         /* All Other Objects */
470
471         else {
472                 /* Notifies allowed on this object? */
473
474                 if (!acpi_ev_is_notify_object(node)) {
475                         status = AE_TYPE;
476                         goto unlock_and_exit;
477                 }
478
479                 /* Check for an existing internal object */
480
481                 obj_desc = acpi_ns_get_attached_object(node);
482                 if (!obj_desc) {
483                         status = AE_NOT_EXIST;
484                         goto unlock_and_exit;
485                 }
486
487                 /* Object exists - make sure there's an existing handler */
488
489                 if (handler_type & ACPI_SYSTEM_NOTIFY) {
490                         notify_obj = obj_desc->common_notify.system_notify;
491                         if ((!notify_obj) ||
492                             (notify_obj->notify.handler != handler)) {
493                                 status = AE_BAD_PARAMETER;
494                                 goto unlock_and_exit;
495                         }
496                         /* Make sure all deferred tasks are completed */
497
498                         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
499                         acpi_os_wait_events_complete(NULL);
500                         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
501                         if (ACPI_FAILURE(status)) {
502                                 return_ACPI_STATUS(status);
503                         }
504
505                         /* Remove the handler */
506                         obj_desc->common_notify.system_notify = NULL;
507                         acpi_ut_remove_reference(notify_obj);
508                 }
509
510                 if (handler_type & ACPI_DEVICE_NOTIFY) {
511                         notify_obj = obj_desc->common_notify.device_notify;
512                         if ((!notify_obj) ||
513                             (notify_obj->notify.handler != handler)) {
514                                 status = AE_BAD_PARAMETER;
515                                 goto unlock_and_exit;
516                         }
517                         /* Make sure all deferred tasks are completed */
518
519                         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
520                         acpi_os_wait_events_complete(NULL);
521                         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
522                         if (ACPI_FAILURE(status)) {
523                                 return_ACPI_STATUS(status);
524                         }
525
526                         /* Remove the handler */
527                         obj_desc->common_notify.device_notify = NULL;
528                         acpi_ut_remove_reference(notify_obj);
529                 }
530         }
531
532       unlock_and_exit:
533         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
534         return_ACPI_STATUS(status);
535 }
536
537 ACPI_EXPORT_SYMBOL(acpi_remove_notify_handler)
538
539 /*******************************************************************************
540  *
541  * FUNCTION:    acpi_install_gpe_handler
542  *
543  * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
544  *                                defined GPEs)
545  *              gpe_number      - The GPE number within the GPE block
546  *              Type            - Whether this GPE should be treated as an
547  *                                edge- or level-triggered interrupt.
548  *              Address         - Address of the handler
549  *              Context         - Value passed to the handler on each GPE
550  *
551  * RETURN:      Status
552  *
553  * DESCRIPTION: Install a handler for a General Purpose Event.
554  *
555  ******************************************************************************/
556 acpi_status
557 acpi_install_gpe_handler(acpi_handle gpe_device,
558                          u32 gpe_number,
559                          u32 type, acpi_event_handler address, void *context)
560 {
561         struct acpi_gpe_event_info *gpe_event_info;
562         struct acpi_handler_info *handler;
563         acpi_status status;
564         acpi_cpu_flags flags;
565
566         ACPI_FUNCTION_TRACE(acpi_install_gpe_handler);
567
568         /* Parameter validation */
569
570         if ((!address) || (type > ACPI_GPE_XRUPT_TYPE_MASK)) {
571                 return_ACPI_STATUS(AE_BAD_PARAMETER);
572         }
573
574         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
575         if (ACPI_FAILURE(status)) {
576                 return_ACPI_STATUS(status);
577         }
578
579         /* Ensure that we have a valid GPE number */
580
581         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
582         if (!gpe_event_info) {
583                 status = AE_BAD_PARAMETER;
584                 goto unlock_and_exit;
585         }
586
587         /* Make sure that there isn't a handler there already */
588
589         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
590             ACPI_GPE_DISPATCH_HANDLER) {
591                 status = AE_ALREADY_EXISTS;
592                 goto unlock_and_exit;
593         }
594
595         /* Allocate and init handler object */
596
597         handler = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_handler_info));
598         if (!handler) {
599                 status = AE_NO_MEMORY;
600                 goto unlock_and_exit;
601         }
602
603         handler->address = address;
604         handler->context = context;
605         handler->method_node = gpe_event_info->dispatch.method_node;
606
607         /* Disable the GPE before installing the handler */
608
609         status = acpi_ev_disable_gpe(gpe_event_info);
610         if (ACPI_FAILURE(status)) {
611                 goto unlock_and_exit;
612         }
613
614         /* Install the handler */
615
616         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
617         gpe_event_info->dispatch.handler = handler;
618
619         /* Setup up dispatch flags to indicate handler (vs. method) */
620
621         gpe_event_info->flags &= ~(ACPI_GPE_XRUPT_TYPE_MASK | ACPI_GPE_DISPATCH_MASK);  /* Clear bits */
622         gpe_event_info->flags |= (u8) (type | ACPI_GPE_DISPATCH_HANDLER);
623
624         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
625
626       unlock_and_exit:
627         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
628         return_ACPI_STATUS(status);
629 }
630
631 ACPI_EXPORT_SYMBOL(acpi_install_gpe_handler)
632
633 /*******************************************************************************
634  *
635  * FUNCTION:    acpi_remove_gpe_handler
636  *
637  * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
638  *                                defined GPEs)
639  *              gpe_number      - The event to remove a handler
640  *              Address         - Address of the handler
641  *
642  * RETURN:      Status
643  *
644  * DESCRIPTION: Remove a handler for a General Purpose acpi_event.
645  *
646  ******************************************************************************/
647 acpi_status
648 acpi_remove_gpe_handler(acpi_handle gpe_device,
649                         u32 gpe_number, acpi_event_handler address)
650 {
651         struct acpi_gpe_event_info *gpe_event_info;
652         struct acpi_handler_info *handler;
653         acpi_status status;
654         acpi_cpu_flags flags;
655
656         ACPI_FUNCTION_TRACE(acpi_remove_gpe_handler);
657
658         /* Parameter validation */
659
660         if (!address) {
661                 return_ACPI_STATUS(AE_BAD_PARAMETER);
662         }
663
664         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
665         if (ACPI_FAILURE(status)) {
666                 return_ACPI_STATUS(status);
667         }
668
669         /* Ensure that we have a valid GPE number */
670
671         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
672         if (!gpe_event_info) {
673                 status = AE_BAD_PARAMETER;
674                 goto unlock_and_exit;
675         }
676
677         /* Make sure that a handler is indeed installed */
678
679         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) !=
680             ACPI_GPE_DISPATCH_HANDLER) {
681                 status = AE_NOT_EXIST;
682                 goto unlock_and_exit;
683         }
684
685         /* Make sure that the installed handler is the same */
686
687         if (gpe_event_info->dispatch.handler->address != address) {
688                 status = AE_BAD_PARAMETER;
689                 goto unlock_and_exit;
690         }
691
692         /* Disable the GPE before removing the handler */
693
694         status = acpi_ev_disable_gpe(gpe_event_info);
695         if (ACPI_FAILURE(status)) {
696                 goto unlock_and_exit;
697         }
698
699         /* Make sure all deferred tasks are completed */
700
701         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
702         acpi_os_wait_events_complete(NULL);
703         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
704         if (ACPI_FAILURE(status)) {
705                 return_ACPI_STATUS(status);
706         }
707
708         /* Remove the handler */
709
710         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
711         handler = gpe_event_info->dispatch.handler;
712
713         /* Restore Method node (if any), set dispatch flags */
714
715         gpe_event_info->dispatch.method_node = handler->method_node;
716         gpe_event_info->flags &= ~ACPI_GPE_DISPATCH_MASK;       /* Clear bits */
717         if (handler->method_node) {
718                 gpe_event_info->flags |= ACPI_GPE_DISPATCH_METHOD;
719         }
720         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
721
722         /* Now we can free the handler object */
723
724         ACPI_FREE(handler);
725
726       unlock_and_exit:
727         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
728         return_ACPI_STATUS(status);
729 }
730
731 ACPI_EXPORT_SYMBOL(acpi_remove_gpe_handler)
732
733 /*******************************************************************************
734  *
735  * FUNCTION:    acpi_acquire_global_lock
736  *
737  * PARAMETERS:  Timeout         - How long the caller is willing to wait
738  *              Handle          - Where the handle to the lock is returned
739  *                                (if acquired)
740  *
741  * RETURN:      Status
742  *
743  * DESCRIPTION: Acquire the ACPI Global Lock
744  *
745  ******************************************************************************/
746 acpi_status acpi_acquire_global_lock(u16 timeout, u32 * handle)
747 {
748         acpi_status status;
749
750         if (!handle) {
751                 return (AE_BAD_PARAMETER);
752         }
753
754         status = acpi_ex_enter_interpreter();
755         if (ACPI_FAILURE(status)) {
756                 return (status);
757         }
758
759         status = acpi_ev_acquire_global_lock(timeout);
760         acpi_ex_exit_interpreter();
761
762         if (ACPI_SUCCESS(status)) {
763                 acpi_gbl_global_lock_handle++;
764                 *handle = acpi_gbl_global_lock_handle;
765         }
766
767         return (status);
768 }
769
770 ACPI_EXPORT_SYMBOL(acpi_acquire_global_lock)
771
772 /*******************************************************************************
773  *
774  * FUNCTION:    acpi_release_global_lock
775  *
776  * PARAMETERS:  Handle      - Returned from acpi_acquire_global_lock
777  *
778  * RETURN:      Status
779  *
780  * DESCRIPTION: Release the ACPI Global Lock. The handle must be valid.
781  *
782  ******************************************************************************/
783 acpi_status acpi_release_global_lock(u32 handle)
784 {
785         acpi_status status;
786
787         if (handle != acpi_gbl_global_lock_handle) {
788                 return (AE_NOT_ACQUIRED);
789         }
790
791         status = acpi_ev_release_global_lock();
792         return (status);
793 }
794
795 ACPI_EXPORT_SYMBOL(acpi_release_global_lock)