ACPICA: _CID support for PCI Root Bridge detection.
[linux-2.6] / drivers / acpi / events / evgpe.c
1 /******************************************************************************
2  *
3  * Module Name: evgpe - General Purpose Event handling and dispatch
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/acevents.h>
46 #include <acpi/acnamesp.h>
47
48 #define _COMPONENT          ACPI_EVENTS
49 ACPI_MODULE_NAME("evgpe")
50
51 /* Local prototypes */
52 static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context);
53
54 /*******************************************************************************
55  *
56  * FUNCTION:    acpi_ev_set_gpe_type
57  *
58  * PARAMETERS:  gpe_event_info          - GPE to set
59  *              Type                    - New type
60  *
61  * RETURN:      Status
62  *
63  * DESCRIPTION: Sets the new type for the GPE (wake, run, or wake/run)
64  *
65  ******************************************************************************/
66
67 acpi_status
68 acpi_ev_set_gpe_type(struct acpi_gpe_event_info *gpe_event_info, u8 type)
69 {
70         acpi_status status;
71
72         ACPI_FUNCTION_TRACE(ev_set_gpe_type);
73
74         /* Validate type and update register enable masks */
75
76         switch (type) {
77         case ACPI_GPE_TYPE_WAKE:
78         case ACPI_GPE_TYPE_RUNTIME:
79         case ACPI_GPE_TYPE_WAKE_RUN:
80                 break;
81
82         default:
83                 return_ACPI_STATUS(AE_BAD_PARAMETER);
84         }
85
86         /* Disable the GPE if currently enabled */
87
88         status = acpi_ev_disable_gpe(gpe_event_info);
89
90         /* Type was validated above */
91
92         gpe_event_info->flags &= ~ACPI_GPE_TYPE_MASK;   /* Clear type bits */
93         gpe_event_info->flags |= type;  /* Insert type */
94         return_ACPI_STATUS(status);
95 }
96
97 /*******************************************************************************
98  *
99  * FUNCTION:    acpi_ev_update_gpe_enable_masks
100  *
101  * PARAMETERS:  gpe_event_info          - GPE to update
102  *              Type                    - What to do: ACPI_GPE_DISABLE or
103  *                                        ACPI_GPE_ENABLE
104  *
105  * RETURN:      Status
106  *
107  * DESCRIPTION: Updates GPE register enable masks based on the GPE type
108  *
109  ******************************************************************************/
110
111 acpi_status
112 acpi_ev_update_gpe_enable_masks(struct acpi_gpe_event_info *gpe_event_info,
113                                 u8 type)
114 {
115         struct acpi_gpe_register_info *gpe_register_info;
116         u8 register_bit;
117
118         ACPI_FUNCTION_TRACE(ev_update_gpe_enable_masks);
119
120         gpe_register_info = gpe_event_info->register_info;
121         if (!gpe_register_info) {
122                 return_ACPI_STATUS(AE_NOT_EXIST);
123         }
124         register_bit = (u8)
125             (1 <<
126              (gpe_event_info->gpe_number - gpe_register_info->base_gpe_number));
127
128         /* 1) Disable case.  Simply clear all enable bits */
129
130         if (type == ACPI_GPE_DISABLE) {
131                 ACPI_CLEAR_BIT(gpe_register_info->enable_for_wake,
132                                register_bit);
133                 ACPI_CLEAR_BIT(gpe_register_info->enable_for_run, register_bit);
134                 return_ACPI_STATUS(AE_OK);
135         }
136
137         /* 2) Enable case.  Set/Clear the appropriate enable bits */
138
139         switch (gpe_event_info->flags & ACPI_GPE_TYPE_MASK) {
140         case ACPI_GPE_TYPE_WAKE:
141                 ACPI_SET_BIT(gpe_register_info->enable_for_wake, register_bit);
142                 ACPI_CLEAR_BIT(gpe_register_info->enable_for_run, register_bit);
143                 break;
144
145         case ACPI_GPE_TYPE_RUNTIME:
146                 ACPI_CLEAR_BIT(gpe_register_info->enable_for_wake,
147                                register_bit);
148                 ACPI_SET_BIT(gpe_register_info->enable_for_run, register_bit);
149                 break;
150
151         case ACPI_GPE_TYPE_WAKE_RUN:
152                 ACPI_SET_BIT(gpe_register_info->enable_for_wake, register_bit);
153                 ACPI_SET_BIT(gpe_register_info->enable_for_run, register_bit);
154                 break;
155
156         default:
157                 return_ACPI_STATUS(AE_BAD_PARAMETER);
158         }
159
160         return_ACPI_STATUS(AE_OK);
161 }
162
163 /*******************************************************************************
164  *
165  * FUNCTION:    acpi_ev_enable_gpe
166  *
167  * PARAMETERS:  gpe_event_info          - GPE to enable
168  *              write_to_hardware       - Enable now, or just mark data structs
169  *                                        (WAKE GPEs should be deferred)
170  *
171  * RETURN:      Status
172  *
173  * DESCRIPTION: Enable a GPE based on the GPE type
174  *
175  ******************************************************************************/
176
177 acpi_status
178 acpi_ev_enable_gpe(struct acpi_gpe_event_info *gpe_event_info,
179                    u8 write_to_hardware)
180 {
181         acpi_status status;
182
183         ACPI_FUNCTION_TRACE(ev_enable_gpe);
184
185         /* Make sure HW enable masks are updated */
186
187         status =
188             acpi_ev_update_gpe_enable_masks(gpe_event_info, ACPI_GPE_ENABLE);
189         if (ACPI_FAILURE(status)) {
190                 return_ACPI_STATUS(status);
191         }
192
193         /* Mark wake-enabled or HW enable, or both */
194
195         switch (gpe_event_info->flags & ACPI_GPE_TYPE_MASK) {
196         case ACPI_GPE_TYPE_WAKE:
197
198                 ACPI_SET_BIT(gpe_event_info->flags, ACPI_GPE_WAKE_ENABLED);
199                 break;
200
201         case ACPI_GPE_TYPE_WAKE_RUN:
202
203                 ACPI_SET_BIT(gpe_event_info->flags, ACPI_GPE_WAKE_ENABLED);
204
205                 /*lint -fallthrough */
206
207         case ACPI_GPE_TYPE_RUNTIME:
208
209                 ACPI_SET_BIT(gpe_event_info->flags, ACPI_GPE_RUN_ENABLED);
210
211                 if (write_to_hardware) {
212
213                         /* Clear the GPE (of stale events), then enable it */
214
215                         status = acpi_hw_clear_gpe(gpe_event_info);
216                         if (ACPI_FAILURE(status)) {
217                                 return_ACPI_STATUS(status);
218                         }
219
220                         /* Enable the requested runtime GPE */
221
222                         status = acpi_hw_write_gpe_enable_reg(gpe_event_info);
223                 }
224                 break;
225
226         default:
227                 return_ACPI_STATUS(AE_BAD_PARAMETER);
228         }
229
230         return_ACPI_STATUS(AE_OK);
231 }
232
233 /*******************************************************************************
234  *
235  * FUNCTION:    acpi_ev_disable_gpe
236  *
237  * PARAMETERS:  gpe_event_info          - GPE to disable
238  *
239  * RETURN:      Status
240  *
241  * DESCRIPTION: Disable a GPE based on the GPE type
242  *
243  ******************************************************************************/
244
245 acpi_status acpi_ev_disable_gpe(struct acpi_gpe_event_info *gpe_event_info)
246 {
247         acpi_status status;
248
249         ACPI_FUNCTION_TRACE(ev_disable_gpe);
250
251         if (!(gpe_event_info->flags & ACPI_GPE_ENABLE_MASK)) {
252                 return_ACPI_STATUS(AE_OK);
253         }
254
255         /* Make sure HW enable masks are updated */
256
257         status =
258             acpi_ev_update_gpe_enable_masks(gpe_event_info, ACPI_GPE_DISABLE);
259         if (ACPI_FAILURE(status)) {
260                 return_ACPI_STATUS(status);
261         }
262
263         /* Mark wake-disabled or HW disable, or both */
264
265         switch (gpe_event_info->flags & ACPI_GPE_TYPE_MASK) {
266         case ACPI_GPE_TYPE_WAKE:
267                 ACPI_CLEAR_BIT(gpe_event_info->flags, ACPI_GPE_WAKE_ENABLED);
268                 break;
269
270         case ACPI_GPE_TYPE_WAKE_RUN:
271                 ACPI_CLEAR_BIT(gpe_event_info->flags, ACPI_GPE_WAKE_ENABLED);
272
273                 /*lint -fallthrough */
274
275         case ACPI_GPE_TYPE_RUNTIME:
276
277                 /* Disable the requested runtime GPE */
278
279                 ACPI_CLEAR_BIT(gpe_event_info->flags, ACPI_GPE_RUN_ENABLED);
280                 status = acpi_hw_write_gpe_enable_reg(gpe_event_info);
281                 break;
282
283         default:
284                 return_ACPI_STATUS(AE_BAD_PARAMETER);
285         }
286
287         return_ACPI_STATUS(AE_OK);
288 }
289
290 /*******************************************************************************
291  *
292  * FUNCTION:    acpi_ev_get_gpe_event_info
293  *
294  * PARAMETERS:  gpe_device          - Device node.  NULL for GPE0/GPE1
295  *              gpe_number          - Raw GPE number
296  *
297  * RETURN:      A GPE event_info struct. NULL if not a valid GPE
298  *
299  * DESCRIPTION: Returns the event_info struct associated with this GPE.
300  *              Validates the gpe_block and the gpe_number
301  *
302  *              Should be called only when the GPE lists are semaphore locked
303  *              and not subject to change.
304  *
305  ******************************************************************************/
306
307 struct acpi_gpe_event_info *acpi_ev_get_gpe_event_info(acpi_handle gpe_device,
308                                                        u32 gpe_number)
309 {
310         union acpi_operand_object *obj_desc;
311         struct acpi_gpe_block_info *gpe_block;
312         acpi_native_uint i;
313
314         ACPI_FUNCTION_ENTRY();
315
316         /* A NULL gpe_block means use the FADT-defined GPE block(s) */
317
318         if (!gpe_device) {
319
320                 /* Examine GPE Block 0 and 1 (These blocks are permanent) */
321
322                 for (i = 0; i < ACPI_MAX_GPE_BLOCKS; i++) {
323                         gpe_block = acpi_gbl_gpe_fadt_blocks[i];
324                         if (gpe_block) {
325                                 if ((gpe_number >= gpe_block->block_base_number)
326                                     && (gpe_number <
327                                         gpe_block->block_base_number +
328                                         (gpe_block->register_count * 8))) {
329                                         return (&gpe_block->
330                                                 event_info[gpe_number -
331                                                            gpe_block->
332                                                            block_base_number]);
333                                 }
334                         }
335                 }
336
337                 /* The gpe_number was not in the range of either FADT GPE block */
338
339                 return (NULL);
340         }
341
342         /* A Non-NULL gpe_device means this is a GPE Block Device */
343
344         obj_desc =
345             acpi_ns_get_attached_object((struct acpi_namespace_node *)
346                                         gpe_device);
347         if (!obj_desc || !obj_desc->device.gpe_block) {
348                 return (NULL);
349         }
350
351         gpe_block = obj_desc->device.gpe_block;
352
353         if ((gpe_number >= gpe_block->block_base_number) &&
354             (gpe_number <
355              gpe_block->block_base_number + (gpe_block->register_count * 8))) {
356                 return (&gpe_block->
357                         event_info[gpe_number - gpe_block->block_base_number]);
358         }
359
360         return (NULL);
361 }
362
363 /*******************************************************************************
364  *
365  * FUNCTION:    acpi_ev_gpe_detect
366  *
367  * PARAMETERS:  gpe_xrupt_list      - Interrupt block for this interrupt.
368  *                                    Can have multiple GPE blocks attached.
369  *
370  * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
371  *
372  * DESCRIPTION: Detect if any GP events have occurred.  This function is
373  *              executed at interrupt level.
374  *
375  ******************************************************************************/
376
377 u32 acpi_ev_gpe_detect(struct acpi_gpe_xrupt_info * gpe_xrupt_list)
378 {
379         acpi_status status;
380         struct acpi_gpe_block_info *gpe_block;
381         struct acpi_gpe_register_info *gpe_register_info;
382         u32 int_status = ACPI_INTERRUPT_NOT_HANDLED;
383         u8 enabled_status_byte;
384         u32 status_reg;
385         u32 enable_reg;
386         acpi_cpu_flags flags;
387         acpi_native_uint i;
388         acpi_native_uint j;
389
390         ACPI_FUNCTION_NAME(ev_gpe_detect);
391
392         /* Check for the case where there are no GPEs */
393
394         if (!gpe_xrupt_list) {
395                 return (int_status);
396         }
397
398         /*
399          * We need to obtain the GPE lock for both the data structs and registers
400          * Note: Not necessary to obtain the hardware lock, since the GPE registers
401          * are owned by the gpe_lock.
402          */
403         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
404
405         /* Examine all GPE blocks attached to this interrupt level */
406
407         gpe_block = gpe_xrupt_list->gpe_block_list_head;
408         while (gpe_block) {
409                 /*
410                  * Read all of the 8-bit GPE status and enable registers
411                  * in this GPE block, saving all of them.
412                  * Find all currently active GP events.
413                  */
414                 for (i = 0; i < gpe_block->register_count; i++) {
415
416                         /* Get the next status/enable pair */
417
418                         gpe_register_info = &gpe_block->register_info[i];
419
420                         /* Read the Status Register */
421
422                         status =
423                             acpi_hw_low_level_read(ACPI_GPE_REGISTER_WIDTH,
424                                                    &status_reg,
425                                                    &gpe_register_info->
426                                                    status_address);
427                         if (ACPI_FAILURE(status)) {
428                                 goto unlock_and_exit;
429                         }
430
431                         /* Read the Enable Register */
432
433                         status =
434                             acpi_hw_low_level_read(ACPI_GPE_REGISTER_WIDTH,
435                                                    &enable_reg,
436                                                    &gpe_register_info->
437                                                    enable_address);
438                         if (ACPI_FAILURE(status)) {
439                                 goto unlock_and_exit;
440                         }
441
442                         ACPI_DEBUG_PRINT((ACPI_DB_INTERRUPTS,
443                                           "Read GPE Register at GPE%X: Status=%02X, Enable=%02X\n",
444                                           gpe_register_info->base_gpe_number,
445                                           status_reg, enable_reg));
446
447                         /* Check if there is anything active at all in this register */
448
449                         enabled_status_byte = (u8) (status_reg & enable_reg);
450                         if (!enabled_status_byte) {
451
452                                 /* No active GPEs in this register, move on */
453
454                                 continue;
455                         }
456
457                         /* Now look at the individual GPEs in this byte register */
458
459                         for (j = 0; j < ACPI_GPE_REGISTER_WIDTH; j++) {
460
461                                 /* Examine one GPE bit */
462
463                                 if (enabled_status_byte & (1 << j)) {
464                                         /*
465                                          * Found an active GPE. Dispatch the event to a handler
466                                          * or method.
467                                          */
468                                         int_status |=
469                                             acpi_ev_gpe_dispatch(&gpe_block->
470                                                                  event_info[(i *
471                                                                              ACPI_GPE_REGISTER_WIDTH)
472                                                                             +
473                                                                             j],
474                                                                  (u32) j +
475                                                                  gpe_register_info->
476                                                                  base_gpe_number);
477                                 }
478                         }
479                 }
480
481                 gpe_block = gpe_block->next;
482         }
483
484       unlock_and_exit:
485
486         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
487         return (int_status);
488 }
489
490 /*******************************************************************************
491  *
492  * FUNCTION:    acpi_ev_asynch_execute_gpe_method
493  *
494  * PARAMETERS:  Context (gpe_event_info) - Info for this GPE
495  *
496  * RETURN:      None
497  *
498  * DESCRIPTION: Perform the actual execution of a GPE control method. This
499  *              function is called from an invocation of acpi_os_execute and
500  *              therefore does NOT execute at interrupt level - so that
501  *              the control method itself is not executed in the context of
502  *              an interrupt handler.
503  *
504  ******************************************************************************/
505
506 static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context)
507 {
508         struct acpi_gpe_event_info *gpe_event_info = (void *)context;
509         acpi_status status;
510         struct acpi_gpe_event_info local_gpe_event_info;
511         struct acpi_evaluate_info *info;
512
513         ACPI_FUNCTION_TRACE(ev_asynch_execute_gpe_method);
514
515         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
516         if (ACPI_FAILURE(status)) {
517                 return_VOID;
518         }
519
520         /* Must revalidate the gpe_number/gpe_block */
521
522         if (!acpi_ev_valid_gpe_event(gpe_event_info)) {
523                 status = acpi_ut_release_mutex(ACPI_MTX_EVENTS);
524                 return_VOID;
525         }
526
527         /* Set the GPE flags for return to enabled state */
528
529         (void)acpi_ev_enable_gpe(gpe_event_info, FALSE);
530
531         /*
532          * Take a snapshot of the GPE info for this level - we copy the
533          * info to prevent a race condition with remove_handler/remove_block.
534          */
535         ACPI_MEMCPY(&local_gpe_event_info, gpe_event_info,
536                     sizeof(struct acpi_gpe_event_info));
537
538         status = acpi_ut_release_mutex(ACPI_MTX_EVENTS);
539         if (ACPI_FAILURE(status)) {
540                 return_VOID;
541         }
542
543         /*
544          * Must check for control method type dispatch one more
545          * time to avoid race with ev_gpe_install_handler
546          */
547         if ((local_gpe_event_info.flags & ACPI_GPE_DISPATCH_MASK) ==
548             ACPI_GPE_DISPATCH_METHOD) {
549
550                 /* Allocate the evaluation information block */
551
552                 info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
553                 if (!info) {
554                         status = AE_NO_MEMORY;
555                 } else {
556                         /*
557                          * Invoke the GPE Method (_Lxx, _Exx) i.e., evaluate the _Lxx/_Exx
558                          * control method that corresponds to this GPE
559                          */
560                         info->prefix_node =
561                             local_gpe_event_info.dispatch.method_node;
562                         info->parameters =
563                             ACPI_CAST_PTR(union acpi_operand_object *,
564                                           gpe_event_info);
565                         info->parameter_type = ACPI_PARAM_GPE;
566                         info->flags = ACPI_IGNORE_RETURN_VALUE;
567
568                         status = acpi_ns_evaluate(info);
569                         ACPI_FREE(info);
570                 }
571
572                 if (ACPI_FAILURE(status)) {
573                         ACPI_EXCEPTION((AE_INFO, status,
574                                         "while evaluating GPE method [%4.4s]",
575                                         acpi_ut_get_node_name
576                                         (local_gpe_event_info.dispatch.
577                                          method_node)));
578                 }
579         }
580
581         if ((local_gpe_event_info.flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
582             ACPI_GPE_LEVEL_TRIGGERED) {
583                 /*
584                  * GPE is level-triggered, we clear the GPE status bit after
585                  * handling the event.
586                  */
587                 status = acpi_hw_clear_gpe(&local_gpe_event_info);
588                 if (ACPI_FAILURE(status)) {
589                         return_VOID;
590                 }
591         }
592
593         /* Enable this GPE */
594
595         (void)acpi_hw_write_gpe_enable_reg(&local_gpe_event_info);
596         return_VOID;
597 }
598
599 /*******************************************************************************
600  *
601  * FUNCTION:    acpi_ev_gpe_dispatch
602  *
603  * PARAMETERS:  gpe_event_info  - Info for this GPE
604  *              gpe_number      - Number relative to the parent GPE block
605  *
606  * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
607  *
608  * DESCRIPTION: Dispatch a General Purpose Event to either a function (e.g. EC)
609  *              or method (e.g. _Lxx/_Exx) handler.
610  *
611  *              This function executes at interrupt level.
612  *
613  ******************************************************************************/
614
615 u32
616 acpi_ev_gpe_dispatch(struct acpi_gpe_event_info *gpe_event_info, u32 gpe_number)
617 {
618         acpi_status status;
619
620         ACPI_FUNCTION_TRACE(ev_gpe_dispatch);
621
622         acpi_gpe_count++;
623
624         /*
625          * If edge-triggered, clear the GPE status bit now.  Note that
626          * level-triggered events are cleared after the GPE is serviced.
627          */
628         if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
629             ACPI_GPE_EDGE_TRIGGERED) {
630                 status = acpi_hw_clear_gpe(gpe_event_info);
631                 if (ACPI_FAILURE(status)) {
632                         ACPI_EXCEPTION((AE_INFO, status,
633                                         "Unable to clear GPE[%2X]",
634                                         gpe_number));
635                         return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
636                 }
637         }
638
639         if (!acpi_gbl_system_awake_and_running) {
640                 /*
641                  * We just woke up because of a wake GPE. Disable any further GPEs
642                  * until we are fully up and running (Only wake GPEs should be enabled
643                  * at this time, but we just brute-force disable them all.)
644                  * 1) We must disable this particular wake GPE so it won't fire again
645                  * 2) We want to disable all wake GPEs, since we are now awake
646                  */
647                 (void)acpi_hw_disable_all_gpes();
648         }
649
650         /*
651          * Dispatch the GPE to either an installed handler, or the control method
652          * associated with this GPE (_Lxx or _Exx). If a handler exists, we invoke
653          * it and do not attempt to run the method. If there is neither a handler
654          * nor a method, we disable this GPE to prevent further such pointless
655          * events from firing.
656          */
657         switch (gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) {
658         case ACPI_GPE_DISPATCH_HANDLER:
659
660                 /*
661                  * Invoke the installed handler (at interrupt level)
662                  * Ignore return status for now.  TBD: leave GPE disabled on error?
663                  */
664                 (void)gpe_event_info->dispatch.handler->address(gpe_event_info->
665                                                                 dispatch.
666                                                                 handler->
667                                                                 context);
668
669                 /* It is now safe to clear level-triggered events. */
670
671                 if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
672                     ACPI_GPE_LEVEL_TRIGGERED) {
673                         status = acpi_hw_clear_gpe(gpe_event_info);
674                         if (ACPI_FAILURE(status)) {
675                                 ACPI_EXCEPTION((AE_INFO, status,
676                                                 "Unable to clear GPE[%2X]",
677                                                 gpe_number));
678                                 return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
679                         }
680                 }
681                 break;
682
683         case ACPI_GPE_DISPATCH_METHOD:
684
685                 /*
686                  * Disable the GPE, so it doesn't keep firing before the method has a
687                  * chance to run (it runs asynchronously with interrupts enabled).
688                  */
689                 status = acpi_ev_disable_gpe(gpe_event_info);
690                 if (ACPI_FAILURE(status)) {
691                         ACPI_EXCEPTION((AE_INFO, status,
692                                         "Unable to disable GPE[%2X]",
693                                         gpe_number));
694                         return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
695                 }
696
697                 /*
698                  * Execute the method associated with the GPE
699                  * NOTE: Level-triggered GPEs are cleared after the method completes.
700                  */
701                 status = acpi_os_execute(OSL_GPE_HANDLER,
702                                          acpi_ev_asynch_execute_gpe_method,
703                                          gpe_event_info);
704                 if (ACPI_FAILURE(status)) {
705                         ACPI_EXCEPTION((AE_INFO, status,
706                                         "Unable to queue handler for GPE[%2X] - event disabled",
707                                         gpe_number));
708                 }
709                 break;
710
711         default:
712
713                 /* No handler or method to run! */
714
715                 ACPI_ERROR((AE_INFO,
716                             "No handler or method for GPE[%2X], disabling event",
717                             gpe_number));
718
719                 /*
720                  * Disable the GPE. The GPE will remain disabled until the ACPI
721                  * Core Subsystem is restarted, or a handler is installed.
722                  */
723                 status = acpi_ev_disable_gpe(gpe_event_info);
724                 if (ACPI_FAILURE(status)) {
725                         ACPI_EXCEPTION((AE_INFO, status,
726                                         "Unable to disable GPE[%2X]",
727                                         gpe_number));
728                         return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
729                 }
730                 break;
731         }
732
733         return_UINT32(ACPI_INTERRUPT_HANDLED);
734 }