aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/acpi/acpica/evgpe.c
blob: afacf4416c738941287f944d599dd13011b6caf6 (plain) (blame)
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
/******************************************************************************
 *
 * Module Name: evgpe - General Purpose Event handling and dispatch
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2008, Intel Corp.
 * 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 "accommon.h"
#include "acevents.h"
#include "acnamesp.h"

#define _COMPONENT          ACPI_EVENTS
ACPI_MODULE_NAME("evgpe")

/* Local prototypes */
static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context);

/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_set_gpe_type
 *
 * PARAMETERS:  gpe_event_info          - GPE to set
 *              Type                    - New type
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Sets the new type for the GPE (wake, run, or wake/run)
 *
 ******************************************************************************/

acpi_status
acpi_ev_set_gpe_type(struct acpi_gpe_event_info *gpe_event_info, u8 type)
{
	acpi_status status;

	ACPI_FUNCTION_TRACE(ev_set_gpe_type);

	/* Validate type and update register enable masks */

	switch (type) {
	case ACPI_GPE_TYPE_WAKE:
	case ACPI_GPE_TYPE_RUNTIME:
	case ACPI_GPE_TYPE_WAKE_RUN:
		break;

	default:
		return_ACPI_STATUS(AE_BAD_PARAMETER);
	}

	/* Disable the GPE if currently enabled */

	status = acpi_ev_disable_gpe(gpe_event_info);

	/* Clear the type bits and insert the new Type */

	gpe_event_info->flags &= ~ACPI_GPE_TYPE_MASK;
	gpe_event_info->flags |= type;
	return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_update_gpe_enable_masks
 *
 * PARAMETERS:  gpe_event_info          - GPE to update
 *              Type                    - What to do: ACPI_GPE_DISABLE or
 *                                        ACPI_GPE_ENABLE
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Updates GPE register enable masks based on the GPE type
 *
 ******************************************************************************/

acpi_status
acpi_ev_update_gpe_enable_masks(struct acpi_gpe_event_info *gpe_event_info,
				u8 type)
{
	struct acpi_gpe_register_info *gpe_register_info;
	u8 register_bit;

	ACPI_FUNCTION_TRACE(ev_update_gpe_enable_masks);

	gpe_register_info = gpe_event_info->register_info;
	if (!gpe_register_info) {
		return_ACPI_STATUS(AE_NOT_EXIST);
	}

	register_bit = (u8)
	    (1 <<
	     (gpe_event_info->gpe_number - gpe_register_info->base_gpe_number));

	/* 1) Disable case. Simply clear all enable bits */

	if (type == ACPI_GPE_DISABLE) {
		ACPI_CLEAR_BIT(gpe_register_info->enable_for_wake,
			       register_bit);
		ACPI_CLEAR_BIT(gpe_register_info->enable_for_run, register_bit);
		return_ACPI_STATUS(AE_OK);
	}

	/* 2) Enable case. Set/Clear the appropriate enable bits */

	switch (gpe_event_info->flags & ACPI_GPE_TYPE_MASK) {
	case ACPI_GPE_TYPE_WAKE:
		ACPI_SET_BIT(gpe_register_info->enable_for_wake, register_bit);
		ACPI_CLEAR_BIT(gpe_register_info->enable_for_run, register_bit);
		break;

	case ACPI_GPE_TYPE_RUNTIME:
		ACPI_CLEAR_BIT(gpe_register_info->enable_for_wake,
			       register_bit);
		ACPI_SET_BIT(gpe_register_info->enable_for_run, register_bit);
		break;

	case ACPI_GPE_TYPE_WAKE_RUN:
		ACPI_SET_BIT(gpe_register_info->enable_for_wake, register_bit);
		ACPI_SET_BIT(gpe_register_info->enable_for_run, register_bit);
		break;

	default:
		return_ACPI_STATUS(AE_BAD_PARAMETER);
	}

	return_ACPI_STATUS(AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_enable_gpe
 *
 * PARAMETERS:  gpe_event_info          - GPE to enable
 *              write_to_hardware       - Enable now, or just mark data structs
 *                                        (WAKE GPEs should be deferred)
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Enable a GPE based on the GPE type
 *
 ******************************************************************************/

acpi_status
acpi_ev_enable_gpe(struct acpi_gpe_event_info *gpe_event_info,
		   u8 write_to_hardware)
{
	acpi_status status;

	ACPI_FUNCTION_TRACE(ev_enable_gpe);

	/* Make sure HW enable masks are updated */

	status =
	    acpi_ev_update_gpe_enable_masks(gpe_event_info, ACPI_GPE_ENABLE);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/* Mark wake-enabled or HW enable, or both */

	switch (gpe_event_info->flags & ACPI_GPE_TYPE_MASK) {
	case ACPI_GPE_TYPE_WAKE:

		ACPI_SET_BIT(gpe_event_info->flags, ACPI_GPE_WAKE_ENABLED);
		break;

	case ACPI_GPE_TYPE_WAKE_RUN:

		ACPI_SET_BIT(gpe_event_info->flags, ACPI_GPE_WAKE_ENABLED);

		/*lint -fallthrough */

	case ACPI_GPE_TYPE_RUNTIME:

		ACPI_SET_BIT(gpe_event_info->flags, ACPI_GPE_RUN_ENABLED);

		if (write_to_hardware) {

			/* Clear the GPE (of stale events), then enable it */

			status = acpi_hw_clear_gpe(gpe_event_info);
			if (ACPI_FAILURE(status)) {
				return_ACPI_STATUS(status);
			}

			/* Enable the requested runtime GPE */

			status = acpi_hw_write_gpe_enable_reg(gpe_event_info);
		}
		break;

	default:
		return_ACPI_STATUS(AE_BAD_PARAMETER);
	}

	return_ACPI_STATUS(AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_disable_gpe
 *
 * PARAMETERS:  gpe_event_info          - GPE to disable
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Disable a GPE based on the GPE type
 *
 ******************************************************************************/

acpi_status acpi_ev_disable_gpe(struct acpi_gpe_event_info *gpe_event_info)
{
	acpi_status status;

	ACPI_FUNCTION_TRACE(ev_disable_gpe);

	/* Make sure HW enable masks are updated */

	status =
	    acpi_ev_update_gpe_enable_masks(gpe_event_info, ACPI_GPE_DISABLE);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/* Clear the appropriate enabled flags for this GPE */

	switch (gpe_event_info->flags & ACPI_GPE_TYPE_MASK) {
	case ACPI_GPE_TYPE_WAKE:
		ACPI_CLEAR_BIT(gpe_event_info->flags, ACPI_GPE_WAKE_ENABLED);
		break;

	case ACPI_GPE_TYPE_WAKE_RUN:
		ACPI_CLEAR_BIT(gpe_event_info->flags, ACPI_GPE_WAKE_ENABLED);

		/* fallthrough */

	case ACPI_GPE_TYPE_RUNTIME:

		/* Disable the requested runtime GPE */

		ACPI_CLEAR_BIT(gpe_event_info->flags, ACPI_GPE_RUN_ENABLED);
		break;

	default:
		break;
	}

	/*
	 * Even if we don't know the GPE type, make sure that we always
	 * disable it. low_disable_gpe will just clear the enable bit for this
	 * GPE and write it. It will not write out the current GPE enable mask,
	 * since this may inadvertently enable GPEs too early, if a rogue GPE has
	 * come in during ACPICA initialization - possibly as a result of AML or
	 * other code that has enabled the GPE.
	 */
	status = acpi_hw_low_disable_gpe(gpe_event_info);
	return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_get_gpe_event_info
 *
 * PARAMETERS:  gpe_device          - Device node. NULL for GPE0/GPE1
 *              gpe_number          - Raw GPE number
 *
 * RETURN:      A GPE event_info struct. NULL if not a valid GPE
 *
 * DESCRIPTION: Returns the event_info struct associated with this GPE.
 *              Validates the gpe_block and the gpe_number
 *
 *              Should be called only when the GPE lists are semaphore locked
 *              and not subject to change.
 *
 ******************************************************************************/

struct acpi_gpe_event_info *acpi_ev_get_gpe_event_info(acpi_handle gpe_device,
						       u32 gpe_number)
{
	union acpi_operand_object *obj_desc;
	struct acpi_gpe_block_info *gpe_block;
	u32 i;

	ACPI_FUNCTION_ENTRY();

	/* A NULL gpe_block means use the FADT-defined GPE block(s) */

	if (!gpe_device) {

		/* Examine GPE Block 0 and 1 (These blocks are permanent) */

		for (i = 0; i < ACPI_MAX_GPE_BLOCKS; i++) {
			gpe_block = acpi_gbl_gpe_fadt_blocks[i];
			if (gpe_block) {
				if ((gpe_number >= gpe_block->block_base_number)
				    && (gpe_number <
					gpe_block->block_base_number +
					(gpe_block->register_count * 8))) {
					return (&gpe_block->
						event_info[gpe_number -
							   gpe_block->
							   block_base_number]);
				}
			}
		}

		/* The gpe_number was not in the range of either FADT GPE block */

		return (NULL);
	}

	/* A Non-NULL gpe_device means this is a GPE Block Device */

	obj_desc = acpi_ns_get_attached_object((struct acpi_namespace_node *)
					       gpe_device);
	if (!obj_desc || !obj_desc->device.gpe_block) {
		return (NULL);
	}

	gpe_block = obj_desc->device.gpe_block;

	if ((gpe_number >= gpe_block->block_base_number) &&
	    (gpe_number <
	     gpe_block->block_base_number + (gpe_block->register_count * 8))) {
		return (&gpe_block->
			event_info[gpe_number - gpe_block->block_base_number]);
	}

	return (NULL);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_gpe_detect
 *
 * PARAMETERS:  gpe_xrupt_list      - Interrupt block for this interrupt.
 *                                    Can have multiple GPE blocks attached.
 *
 * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 *
 * DESCRIPTION: Detect if any GP events have occurred. This function is
 *              executed at interrupt level.
 *
 ******************************************************************************/

u32 acpi_ev_gpe_detect(struct acpi_gpe_xrupt_info * gpe_xrupt_list)
{
	acpi_status status;
	struct acpi_gpe_block_info *gpe_block;
	struct acpi_gpe_register_info *gpe_register_info;
	u32 int_status = ACPI_INTERRUPT_NOT_HANDLED;
	u8 enabled_status_byte;
	u32 status_reg;
	u32 enable_reg;
	acpi_cpu_flags flags;
	u32 i;
	u32 j;

	ACPI_FUNCTION_NAME(ev_gpe_detect);

	/* Check for the case where there are no GPEs */

	if (!gpe_xrupt_list) {
		return (int_status);
	}

	/*
	 * We need to obtain the GPE lock for both the data structs and registers
	 * Note: Not necessary to obtain the hardware lock, since the GPE
	 * registers are owned by the gpe_lock.
	 */
	flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);

	/* Examine all GPE blocks attached to this interrupt level */

	gpe_block = gpe_xrupt_list->gpe_block_list_head;
	while (gpe_block) {
		/*
		 * Read all of the 8-bit GPE status and enable registers in this GPE
		 * block, saving all of them. Find all currently active GP events.
		 */
		for (i = 0; i < gpe_block->register_count; i++) {

			/* Get the next status/enable pair */

			gpe_register_info = &gpe_block->register_info[i];

			/* Read the Status Register */

			status =
			    acpi_hw_read(&status_reg,
					 &gpe_register_info->status_address);
			if (ACPI_FAILURE(status)) {
				goto unlock_and_exit;
			}

			/* Read the Enable Register */

			status =
			    acpi_hw_read(&enable_reg,
					 &gpe_register_info->enable_address);
			if (ACPI_FAILURE(status)) {
				goto unlock_and_exit;
			}

			ACPI_DEBUG_PRINT((ACPI_DB_INTERRUPTS,
					  "Read GPE Register at GPE%X: Status=%02X, Enable=%02X\n",
					  gpe_register_info->base_gpe_number,
					  status_reg, enable_reg));

			/* Check if there is anything active at all in this register */

			enabled_status_byte = (u8) (status_reg & enable_reg);
			if (!enabled_status_byte) {

				/* No active GPEs in this register, move on */

				continue;
			}

			/* Now look at the individual GPEs in this byte register */

			for (j = 0; j < ACPI_GPE_REGISTER_WIDTH; j++) {

				/* Examine one GPE bit */

				if (enabled_status_byte & (1 << j)) {
					/*
					 * Found an active GPE. Dispatch the event to a handler
					 * or method.
					 */
					int_status |=
					    acpi_ev_gpe_dispatch(&gpe_block->
						event_info[((acpi_size) i * ACPI_GPE_REGISTER_WIDTH) + j], j + gpe_register_info->base_gpe_number);
				}
			}
		}

		gpe_block = gpe_block->next;
	}

      unlock_and_exit:

	acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
	return (int_status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_asynch_execute_gpe_method
 *
 * PARAMETERS:  Context (gpe_event_info) - Info for this GPE
 *
 * RETURN:      None
 *
 * DESCRIPTION: Perform the actual execution of a GPE control method. This
 *              function is called from an invocation of acpi_os_execute and
 *              therefore does NOT execute at interrupt level - so that
 *              the control method itself is not executed in the context of
 *              an interrupt handler.
 *
 ******************************************************************************/
static void acpi_ev_asynch_enable_gpe(void *context);

static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context)
{
	struct acpi_gpe_event_info *gpe_event_info = (void *)context;
	acpi_status status;
	struct acpi_gpe_event_info local_gpe_event_info;
	struct acpi_evaluate_info *info;

	ACPI_FUNCTION_TRACE(ev_asynch_execute_gpe_method);

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

	/* Must revalidate the gpe_number/gpe_block */

	if (!acpi_ev_valid_gpe_event(gpe_event_info)) {
		status = acpi_ut_release_mutex(ACPI_MTX_EVENTS);
		return_VOID;
	}

	/* Set the GPE flags for return to enabled state */

	(void)acpi_ev_enable_gpe(gpe_event_info, FALSE);

	/*
	 * Take a snapshot of the GPE info for this level - we copy the info to
	 * prevent a race condition with remove_handler/remove_block.
	 */
	ACPI_MEMCPY(&local_gpe_event_info, gpe_event_info,
		    sizeof(struct acpi_gpe_event_info));

	status = acpi_ut_release_mutex(ACPI_MTX_EVENTS);
	if (ACPI_FAILURE(status)) {
		return_VOID;
	}

	/*
	 * Must check for control method type dispatch one more time to avoid a
	 * race with ev_gpe_install_handler
	 */
	if ((local_gpe_event_info.flags & ACPI_GPE_DISPATCH_MASK) ==
	    ACPI_GPE_DISPATCH_METHOD) {

		/* Allocate the evaluation information block */

		info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
		if (!info) {
			status = AE_NO_MEMORY;
		} else {
			/*
			 * Invoke the GPE Method (_Lxx, _Exx) i.e., evaluate the _Lxx/_Exx
			 * control method that corresponds to this GPE
			 */
			info->prefix_node =
			    local_gpe_event_info.dispatch.method_node;
			info->flags = ACPI_IGNORE_RETURN_VALUE;

			status = acpi_ns_evaluate(info);
			ACPI_FREE(info);
		}

		if (ACPI_FAILURE(status)) {
			ACPI_EXCEPTION((AE_INFO, status,
					"while evaluating GPE method [%4.4s]",
					acpi_ut_get_node_name
					(local_gpe_event_info.dispatch.
					 method_node)));
		}
	}
	/* Defer enabling of GPE until all notify handlers are done */
	acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_ev_asynch_enable_gpe,
				gpe_event_info);
	return_VOID;
}

static void acpi_ev_asynch_enable_gpe(void *context)
{
	struct acpi_gpe_event_info *gpe_event_info = context;
	acpi_status status;
	if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
	    ACPI_GPE_LEVEL_TRIGGERED) {
		/*
		 * GPE is level-triggered, we clear the GPE status bit after handling
		 * the event.
		 */
		status = acpi_hw_clear_gpe(gpe_event_info);
		if (ACPI_FAILURE(status)) {
			return_VOID;
		}
	}

	/* Enable this GPE */
	(void)acpi_hw_write_gpe_enable_reg(gpe_event_info);
	return_VOID;
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_gpe_dispatch
 *
 * PARAMETERS:  gpe_event_info  - Info for this GPE
 *              gpe_number      - Number relative to the parent GPE block
 *
 * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 *
 * DESCRIPTION: Dispatch a General Purpose Event to either a function (e.g. EC)
 *              or method (e.g. _Lxx/_Exx) handler.
 *
 *              This function executes at interrupt level.
 *
 ******************************************************************************/

u32
acpi_ev_gpe_dispatch(struct acpi_gpe_event_info *gpe_event_info, u32 gpe_number)
{
	acpi_status status;

	ACPI_FUNCTION_TRACE(ev_gpe_dispatch);

	acpi_os_gpe_count(gpe_number);

	/*
	 * If edge-triggered, clear the GPE status bit now. Note that
	 * level-triggered events are cleared after the GPE is serviced.
	 */
	if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
	    ACPI_GPE_EDGE_TRIGGERED) {
		status = acpi_hw_clear_gpe(gpe_event_info);
		if (ACPI_FAILURE(status)) {
			ACPI_EXCEPTION((AE_INFO, status,
					"Unable to clear GPE[%2X]",
					gpe_number));
			return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
		}
	}

	/*
	 * Dispatch the GPE to either an installed handler, or the control method
	 * associated with this GPE (_Lxx or _Exx). If a handler exists, we invoke
	 * it and do not attempt to run the method. If there is neither a handler
	 * nor a method, we disable this GPE to prevent further such pointless
	 * events from firing.
	 */
	switch (gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) {
	case ACPI_GPE_DISPATCH_HANDLER:

		/*
		 * Invoke the installed handler (at interrupt level)
		 * Ignore return status for now.
		 * TBD: leave GPE disabled on error?
		 */
		(void)gpe_event_info->dispatch.handler->address(gpe_event_info->
								dispatch.
								handler->
								context);

		/* It is now safe to clear level-triggered events. */

		if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
		    ACPI_GPE_LEVEL_TRIGGERED) {
			status = acpi_hw_clear_gpe(gpe_event_info);
			if (ACPI_FAILURE(status)) {
				ACPI_EXCEPTION((AE_INFO, status,
						"Unable to clear GPE[%2X]",
						gpe_number));
				return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
			}
		}
		break;

	case ACPI_GPE_DISPATCH_METHOD:

		/*
		 * Disable the GPE, so it doesn't keep firing before the method has a
		 * chance to run (it runs asynchronously with interrupts enabled).
		 */
		status = acpi_ev_disable_gpe(gpe_event_info);
		if (ACPI_FAILURE(status)) {
			ACPI_EXCEPTION((AE_INFO, status,
					"Unable to disable GPE[%2X]",
					gpe_number));
			return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
		}

		/*
		 * Execute the method associated with the GPE
		 * NOTE: Level-triggered GPEs are cleared after the method completes.
		 */
		status = acpi_os_execute(OSL_GPE_HANDLER,
					 acpi_ev_asynch_execute_gpe_method,
					 gpe_event_info);
		if (ACPI_FAILURE(status)) {
			ACPI_EXCEPTION((AE_INFO, status,
					"Unable to queue handler for GPE[%2X] - event disabled",
					gpe_number));
		}
		break;

	default:

		/* No handler or method to run! */

		ACPI_ERROR((AE_INFO,
			    "No handler or method for GPE[%2X], disabling event",
			    gpe_number));

		/*
		 * Disable the GPE. The GPE will remain disabled until the ACPICA
		 * Core Subsystem is restarted, or a handler is installed.
		 */
		status = acpi_ev_disable_gpe(gpe_event_info);
		if (ACPI_FAILURE(status)) {
			ACPI_EXCEPTION((AE_INFO, status,
					"Unable to disable GPE[%2X]",
					gpe_number));
			return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
		}
		break;
	}

	return_UINT32(ACPI_INTERRUPT_HANDLED);
}