summaryrefslogtreecommitdiffstats
path: root/drivers/acpi/events/evxface.c
blob: 4f948df17ab975f15cc6a5d22c842a10332d55e1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
/******************************************************************************
 *
 * Module Name: evxface - External interfaces for ACPI events
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2006, R. Byron Moore
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    substantially similar to the "NO WARRANTY" disclaimer below
 *    ("Disclaimer") and any redistribution must be conditioned upon
 *    including a substantially similar Disclaimer requirement for further
 *    binary redistribution.
 * 3. Neither the names of the above-listed copyright holders nor the names
 *    of any contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * NO WARRANTY
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGES.
 */

#include <acpi/acpi.h>
#include <acpi/acnamesp.h>
#include <acpi/acevents.h>
#include <acpi/acinterp.h>

#define _COMPONENT          ACPI_EVENTS
ACPI_MODULE_NAME("evxface")

/*******************************************************************************
 *
 * FUNCTION:    acpi_install_exception_handler
 *
 * PARAMETERS:  Handler         - Pointer to the handler function for the
 *                                event
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Saves the pointer to the handler function
 *
 ******************************************************************************/
#ifdef ACPI_FUTURE_USAGE
acpi_status acpi_install_exception_handler(acpi_exception_handler handler)
{
	acpi_status status;

	ACPI_FUNCTION_TRACE(acpi_install_exception_handler);

	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/* Don't allow two handlers. */

	if (acpi_gbl_exception_handler) {
		status = AE_ALREADY_EXISTS;
		goto cleanup;
	}

	/* Install the handler */

	acpi_gbl_exception_handler = handler;

      cleanup:
	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
	return_ACPI_STATUS(status);
}

ACPI_EXPORT_SYMBOL(acpi_install_exception_handler)
#endif				/*  ACPI_FUTURE_USAGE  */

/*******************************************************************************
 *
 * FUNCTION:    acpi_install_fixed_event_handler
 *
 * PARAMETERS:  Event           - Event type to enable.
 *              Handler         - Pointer to the handler function for the
 *                                event
 *              Context         - Value passed to the handler on each GPE
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Saves the pointer to the handler function and then enables the
 *              event.
 *
 ******************************************************************************/
acpi_status
acpi_install_fixed_event_handler(u32 event,
				 acpi_event_handler handler, void *context)
{
	acpi_status status;

	ACPI_FUNCTION_TRACE(acpi_install_fixed_event_handler);

	/* Parameter validation */

	if (event > ACPI_EVENT_MAX) {
		return_ACPI_STATUS(AE_BAD_PARAMETER);
	}

	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/* Don't allow two handlers. */

	if (NULL != acpi_gbl_fixed_event_handlers[event].handler) {
		status = AE_ALREADY_EXISTS;
		goto cleanup;
	}

	/* Install the handler before enabling the event */

	acpi_gbl_fixed_event_handlers[event].handler = handler;
	acpi_gbl_fixed_event_handlers[event].context = context;

	status = acpi_clear_event(event);
	if (ACPI_SUCCESS(status))
		status = acpi_enable_event(event, 0);
	if (ACPI_FAILURE(status)) {
		ACPI_WARNING((AE_INFO, "Could not enable fixed event %X",
			      event));

		/* Remove the handler */

		acpi_gbl_fixed_event_handlers[event].handler = NULL;
		acpi_gbl_fixed_event_handlers[event].context = NULL;
	} else {
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "Enabled fixed event %X, Handler=%p\n", event,
				  handler));
	}

      cleanup:
	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
	return_ACPI_STATUS(status);
}

ACPI_EXPORT_SYMBOL(acpi_install_fixed_event_handler)

/*******************************************************************************
 *
 * FUNCTION:    acpi_remove_fixed_event_handler
 *
 * PARAMETERS:  Event           - Event type to disable.
 *              Handler         - Address of the handler
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Disables the event and unregisters the event handler.
 *
 ******************************************************************************/
acpi_status
acpi_remove_fixed_event_handler(u32 event, acpi_event_handler handler)
{
	acpi_status status = AE_OK;

	ACPI_FUNCTION_TRACE(acpi_remove_fixed_event_handler);

	/* Parameter validation */

	if (event > ACPI_EVENT_MAX) {
		return_ACPI_STATUS(AE_BAD_PARAMETER);
	}

	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/* Disable the event before removing the handler */

	status = acpi_disable_event(event, 0);

	/* Always Remove the handler */

	acpi_gbl_fixed_event_handlers[event].handler = NULL;
	acpi_gbl_fixed_event_handlers[event].context = NULL;

	if (ACPI_FAILURE(status)) {
		ACPI_WARNING((AE_INFO,
			      "Could not write to fixed event enable register %X",
			      event));
	} else {
		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Disabled fixed event %X\n",
				  event));
	}

	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
	return_ACPI_STATUS(status);
}

ACPI_EXPORT_SYMBOL(acpi_remove_fixed_event_handler)

/*******************************************************************************
 *
 * FUNCTION:    acpi_install_notify_handler
 *
 * PARAMETERS:  Device          - The device for which notifies will be handled
 *              handler_type    - The type of handler:
 *                                  ACPI_SYSTEM_NOTIFY: system_handler (00-7f)
 *                                  ACPI_DEVICE_NOTIFY: driver_handler (80-ff)
 *                                  ACPI_ALL_NOTIFY:  both system and device
 *              Handler         - Address of the handler
 *              Context         - Value passed to the handler on each GPE
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Install a handler for notifies on an ACPI device
 *
 ******************************************************************************/
acpi_status
acpi_install_notify_handler(acpi_handle device,
			    u32 handler_type,
			    acpi_notify_handler handler, void *context)
{
	union acpi_operand_object *obj_desc;
	union acpi_operand_object *notify_obj;
	struct acpi_namespace_node *node;
	acpi_status status;

	ACPI_FUNCTION_TRACE(acpi_install_notify_handler);

	/* Parameter validation */

	if ((!device) ||
	    (!handler) || (handler_type > ACPI_MAX_NOTIFY_HANDLER_TYPE)) {
		return_ACPI_STATUS(AE_BAD_PARAMETER);
	}

	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/* Convert and validate the device handle */

	node = acpi_ns_map_handle_to_node(device);
	if (!node) {
		status = AE_BAD_PARAMETER;
		goto unlock_and_exit;
	}

	/*
	 * Root Object:
	 * Registering a notify handler on the root object indicates that the
	 * caller wishes to receive notifications for all objects.  Note that
	 * only one <external> global handler can be regsitered (per notify type).
	 */
	if (device == ACPI_ROOT_OBJECT) {

		/* Make sure the handler is not already installed */

		if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
		     acpi_gbl_system_notify.handler) ||
		    ((handler_type & ACPI_DEVICE_NOTIFY) &&
		     acpi_gbl_device_notify.handler)) {
			status = AE_ALREADY_EXISTS;
			goto unlock_and_exit;
		}

		if (handler_type & ACPI_SYSTEM_NOTIFY) {
			acpi_gbl_system_notify.node = node;
			acpi_gbl_system_notify.handler = handler;
			acpi_gbl_system_notify.context = context;
		}

		if (handler_type & ACPI_DEVICE_NOTIFY) {
			acpi_gbl_device_notify.node = node;
			acpi_gbl_device_notify.handler = handler;
			acpi_gbl_device_notify.context = context;
		}

		/* Global notify handler installed */
	}

	/*
	 * All Other Objects:
	 * Caller will only receive notifications specific to the target object.
	 * Note that only certain object types can receive notifications.
	 */
	else {
		/* Notifies allowed on this object? */

		if (!acpi_ev_is_notify_object(node)) {
			status = AE_TYPE;
			goto unlock_and_exit;
		}

		/* Check for an existing internal object */

		obj_desc = acpi_ns_get_attached_object(node);
		if (obj_desc) {

			/* Object exists - make sure there's no handler */

			if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
			     obj_desc->common_notify.system_notify) ||
			    ((handler_type & ACPI_DEVICE_NOTIFY) &&
			     obj_desc->common_notify.device_notify)) {
				status = AE_ALREADY_EXISTS;
				goto unlock_and_exit;
			}
		} else {
			/* Create a new object */

			obj_desc = acpi_ut_create_internal_object(node->type);
			if (!obj_desc) {
				status = AE_NO_MEMORY;
				goto unlock_and_exit;
			}

			/* Attach new object to the Node */

			status =
			    acpi_ns_attach_object(device, obj_desc, node->type);

			/* Remove local reference to the object */

			acpi_ut_remove_reference(obj_desc);
			if (ACPI_FAILURE(status)) {
				goto unlock_and_exit;
			}
		}

		/* Install the handler */

		notify_obj =
		    acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_NOTIFY);
		if (!notify_obj) {
			status = AE_NO_MEMORY;
			goto unlock_and_exit;
		}

		notify_obj->notify.node = node;
		notify_obj->notify.handler = handler;
		notify_obj->notify.context = context;

		if (handler_type & ACPI_SYSTEM_NOTIFY) {
			obj_desc->common_notify.system_notify = notify_obj;
		}

		if (handler_type & ACPI_DEVICE_NOTIFY) {
			obj_desc->common_notify.device_notify = notify_obj;
		}

		if (handler_type == ACPI_ALL_NOTIFY) {

			/* Extra ref if installed in both */

			acpi_ut_add_reference(notify_obj);
		}
	}

      unlock_and_exit:
	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
	return_ACPI_STATUS(status);
}

ACPI_EXPORT_SYMBOL(acpi_install_notify_handler)

/*******************************************************************************
 *
 * FUNCTION:    acpi_remove_notify_handler
 *
 * PARAMETERS:  Device          - The device for which notifies will be handled
 *              handler_type    - The type of handler:
 *                                  ACPI_SYSTEM_NOTIFY: system_handler (00-7f)
 *                                  ACPI_DEVICE_NOTIFY: driver_handler (80-ff)
 *                                  ACPI_ALL_NOTIFY:  both system and device
 *              Handler         - Address of the handler
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Remove a handler for notifies on an ACPI device
 *
 ******************************************************************************/
acpi_status
acpi_remove_notify_handler(acpi_handle device,
			   u32 handler_type, acpi_notify_handler handler)
{
	union acpi_operand_object *notify_obj;
	union acpi_operand_object *obj_desc;
	struct acpi_namespace_node *node;
	acpi_status status;

	ACPI_FUNCTION_TRACE(acpi_remove_notify_handler);

	/* Parameter validation */

	if ((!device) ||
	    (!handler) || (handler_type > ACPI_MAX_NOTIFY_HANDLER_TYPE)) {
		status = AE_BAD_PARAMETER;
		goto exit;
	}

	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
	if (ACPI_FAILURE(status)) {
		goto exit;
	}

	/* Convert and validate the device handle */

	node = acpi_ns_map_handle_to_node(device);
	if (!node) {
		status = AE_BAD_PARAMETER;
		goto unlock;
	}

	/* Root Object */

	if (device == ACPI_ROOT_OBJECT) {
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "Removing notify handler for namespace root object\n"));

		if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
		     !acpi_gbl_system_notify.handler) ||
		    ((handler_type & ACPI_DEVICE_NOTIFY) &&
		     !acpi_gbl_device_notify.handler)) {
			status = AE_NOT_EXIST;
			goto unlock;
		}

		/* Make sure all deferred tasks are completed */

		(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
		acpi_os_wait_events_complete(NULL);
		status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
		if (ACPI_FAILURE(status)) {
			goto exit;
		}

		if (handler_type & ACPI_SYSTEM_NOTIFY) {
			acpi_gbl_system_notify.node = NULL;
			acpi_gbl_system_notify.handler = NULL;
			acpi_gbl_system_notify.context = NULL;
		}

		if (handler_type & ACPI_DEVICE_NOTIFY) {
			acpi_gbl_device_notify.node = NULL;
			acpi_gbl_device_notify.handler = NULL;
			acpi_gbl_device_notify.context = NULL;
		}
	}

	/* All Other Objects */

	else {
		/* Notifies allowed on this object? */

		if (!acpi_ev_is_notify_object(node)) {
			status = AE_TYPE;
			goto unlock;
		}

		/* Check for an existing internal object */

		obj_desc = acpi_ns_get_attached_object(node);
		if (!obj_desc) {
			status = AE_NOT_EXIST;
			goto unlock;
		}

		/* Object exists - make sure there's an existing handler */

		if (handler_type & ACPI_SYSTEM_NOTIFY) {
			notify_obj = obj_desc->common_notify.system_notify;
			if ((!notify_obj) ||
			    (notify_obj->notify.handler != handler)) {
				status = AE_BAD_PARAMETER;
				goto unlock;
			}
			/* Make sure all deferred tasks are completed */

			(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
			acpi_os_wait_events_complete(NULL);
			status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
			if (ACPI_FAILURE(status)) {
				goto exit;
			}

			/* Remove the handler */
			obj_desc->common_notify.system_notify = NULL;
			acpi_ut_remove_reference(notify_obj);
		}

		if (handler_type & ACPI_DEVICE_NOTIFY) {
			notify_obj = obj_desc->common_notify.device_notify;
			if ((!notify_obj) ||
			    (notify_obj->notify.handler != handler)) {
				status = AE_BAD_PARAMETER;
				goto unlock;
			}
			/* Make sure all deferred tasks are completed */

			(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
			acpi_os_wait_events_complete(NULL);
			status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
			if (ACPI_FAILURE(status)) {
				goto exit;
			}

			/* Remove the handler */
			obj_desc->common_notify.device_notify = NULL;
			acpi_ut_remove_reference(notify_obj);
		}
	}

unlock:
	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
exit:
	if (ACPI_FAILURE(status))
		ACPI_EXCEPTION((AE_INFO, status, "Removing notify handler"));
	return_ACPI_STATUS(status);
}

ACPI_EXPORT_SYMBOL(acpi_remove_notify_handler)

/*******************************************************************************
 *
 * FUNCTION:    acpi_install_gpe_handler
 *
 * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
 *                                defined GPEs)
 *              gpe_number      - The GPE number within the GPE block
 *              Type            - Whether this GPE should be treated as an
 *                                edge- or level-triggered interrupt.
 *              Address         - Address of the handler
 *              Context         - Value passed to the handler on each GPE
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Install a handler for a General Purpose Event.
 *
 ******************************************************************************/
acpi_status
acpi_install_gpe_handler(acpi_handle gpe_device,
			 u32 gpe_number,
			 u32 type, acpi_event_handler address, void *context)
{
	struct acpi_gpe_event_info *gpe_event_info;
	struct acpi_handler_info *handler;
	acpi_status status;
	acpi_cpu_flags flags;

	ACPI_FUNCTION_TRACE(acpi_install_gpe_handler);

	/* Parameter validation */

	if ((!address) || (type > ACPI_GPE_XRUPT_TYPE_MASK)) {
		status = AE_BAD_PARAMETER;
		goto exit;
	}

	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
	if (ACPI_FAILURE(status)) {
		goto exit;
	}

	/* Ensure that we have a valid GPE number */

	gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
	if (!gpe_event_info) {
		status = AE_BAD_PARAMETER;
		goto unlock;
	}

	/* Make sure that there isn't a handler there already */

	if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
	    ACPI_GPE_DISPATCH_HANDLER) {
		status = AE_ALREADY_EXISTS;
		goto unlock;
	}

	/* Allocate and init handler object */

	handler = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_handler_info));
	if (!handler) {
		status = AE_NO_MEMORY;
		goto unlock;
	}

	handler->address = address;
	handler->context = context;
	handler->method_node = gpe_event_info->dispatch.method_node;

	/* Disable the GPE before installing the handler */

	status = acpi_ev_disable_gpe(gpe_event_info);
	if (ACPI_FAILURE(status)) {
		goto unlock;
	}

	/* Install the handler */

	flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
	gpe_event_info->dispatch.handler = handler;

	/* Setup up dispatch flags to indicate handler (vs. method) */

	gpe_event_info->flags &= ~(ACPI_GPE_XRUPT_TYPE_MASK | ACPI_GPE_DISPATCH_MASK);	/* Clear bits */
	gpe_event_info->flags |= (u8) (type | ACPI_GPE_DISPATCH_HANDLER);

	acpi_os_release_lock(acpi_gbl_gpe_lock, flags);

unlock:
	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
exit:
	if (ACPI_FAILURE(status))
		ACPI_EXCEPTION((AE_INFO, status,
				"Installing notify handler failed"));
	return_ACPI_STATUS(status);
}

ACPI_EXPORT_SYMBOL(acpi_install_gpe_handler)

/*******************************************************************************
 *
 * FUNCTION:    acpi_remove_gpe_handler
 *
 * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
 *                                defined GPEs)
 *              gpe_number      - The event to remove a handler
 *              Address         - Address of the handler
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Remove a handler for a General Purpose acpi_event.
 *
 ******************************************************************************/
acpi_status
acpi_remove_gpe_handler(acpi_handle gpe_device,
			u32 gpe_number, acpi_event_handler address)
{
	struct acpi_gpe_event_info *gpe_event_info;
	struct acpi_handler_info *handler;
	acpi_status status;
	acpi_cpu_flags flags;

	ACPI_FUNCTION_TRACE(acpi_remove_gpe_handler);

	/* Parameter validation */

	if (!address) {
		return_ACPI_STATUS(AE_BAD_PARAMETER);
	}

	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/* Ensure that we have a valid GPE number */

	gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
	if (!gpe_event_info) {
		status = AE_BAD_PARAMETER;
		goto unlock_and_exit;
	}

	/* Make sure that a handler is indeed installed */

	if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) !=
	    ACPI_GPE_DISPATCH_HANDLER) {
		status = AE_NOT_EXIST;
		goto unlock_and_exit;
	}

	/* Make sure that the installed handler is the same */

	if (gpe_event_info->dispatch.handler->address != address) {
		status = AE_BAD_PARAMETER;
		goto unlock_and_exit;
	}

	/* Disable the GPE before removing the handler */

	status = acpi_ev_disable_gpe(gpe_event_info);
	if (ACPI_FAILURE(status)) {
		goto unlock_and_exit;
	}

	/* Make sure all deferred tasks are completed */

	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
	acpi_os_wait_events_complete(NULL);
	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/* Remove the handler */

	flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
	handler = gpe_event_info->dispatch.handler;

	/* Restore Method node (if any), set dispatch flags */

	gpe_event_info->dispatch.method_node = handler->method_node;
	gpe_event_info->flags &= ~ACPI_GPE_DISPATCH_MASK;	/* Clear bits */
	if (handler->method_node) {
		gpe_event_info->flags |= ACPI_GPE_DISPATCH_METHOD;
	}
	acpi_os_release_lock(acpi_gbl_gpe_lock, flags);

	/* Now we can free the handler object */

	ACPI_FREE(handler);

      unlock_and_exit:
	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
	return_ACPI_STATUS(status);
}

ACPI_EXPORT_SYMBOL(acpi_remove_gpe_handler)

/*******************************************************************************
 *
 * FUNCTION:    acpi_acquire_global_lock
 *
 * PARAMETERS:  Timeout         - How long the caller is willing to wait
 *              Handle          - Where the handle to the lock is returned
 *                                (if acquired)
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Acquire the ACPI Global Lock
 *
 ******************************************************************************/
acpi_status acpi_acquire_global_lock(u16 timeout, u32 * handle)
{
	acpi_status status;

	if (!handle) {
		return (AE_BAD_PARAMETER);
	}

	status = acpi_ex_enter_interpreter();
	if (ACPI_FAILURE(status)) {
		return (status);
	}

	status = acpi_ev_acquire_global_lock(timeout);
	acpi_ex_exit_interpreter();

	if (ACPI_SUCCESS(status)) {
		acpi_gbl_global_lock_handle++;
		*handle = acpi_gbl_global_lock_handle;
	}

	return (status);
}

ACPI_EXPORT_SYMBOL(acpi_acquire_global_lock)

/*******************************************************************************
 *
 * FUNCTION:    acpi_release_global_lock
 *
 * PARAMETERS:  Handle      - Returned from acpi_acquire_global_lock
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Release the ACPI Global Lock. The handle must be valid.
 *
 ******************************************************************************/
acpi_status acpi_release_global_lock(u32 handle)
{
	acpi_status status;

	if (handle != acpi_gbl_global_lock_handle) {
		return (AE_NOT_ACQUIRED);
	}

	status = acpi_ev_release_global_lock();
	return (status);
}

ACPI_EXPORT_SYMBOL(acpi_release_global_lock)