Revert "ARM: tegra: tegratab: dummy change"
[linux-2.6.git] / drivers / acpi / acpica / evxfgpe.c
1 /******************************************************************************
2  *
3  * Module Name: evxfgpe - External Interfaces for General Purpose Events (GPEs)
4  *
5  *****************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2012, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43
44 #include <linux/export.h>
45 #include <acpi/acpi.h>
46 #include "accommon.h"
47 #include "acevents.h"
48 #include "acnamesp.h"
49
50 #define _COMPONENT          ACPI_EVENTS
51 ACPI_MODULE_NAME("evxfgpe")
52
53 #if (!ACPI_REDUCED_HARDWARE)    /* Entire module */
54 /******************************************************************************
55  *
56  * FUNCTION:    acpi_update_all_gpes
57  *
58  * PARAMETERS:  None
59  *
60  * RETURN:      Status
61  *
62  * DESCRIPTION: Complete GPE initialization and enable all GPEs that have
63  *              associated _Lxx or _Exx methods and are not pointed to by any
64  *              device _PRW methods (this indicates that these GPEs are
65  *              generally intended for system or device wakeup. Such GPEs
66  *              have to be enabled directly when the devices whose _PRW
67  *              methods point to them are set up for wakeup signaling.)
68  *
69  * NOTE: Should be called after any GPEs are added to the system. Primarily,
70  * after the system _PRW methods have been run, but also after a GPE Block
71  * Device has been added or if any new GPE methods have been added via a
72  * dynamic table load.
73  *
74  ******************************************************************************/
75
76 acpi_status acpi_update_all_gpes(void)
77 {
78         acpi_status status;
79
80         ACPI_FUNCTION_TRACE(acpi_update_all_gpes);
81
82         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
83         if (ACPI_FAILURE(status)) {
84                 return_ACPI_STATUS(status);
85         }
86
87         if (acpi_gbl_all_gpes_initialized) {
88                 goto unlock_and_exit;
89         }
90
91         status = acpi_ev_walk_gpe_list(acpi_ev_initialize_gpe_block, NULL);
92         if (ACPI_SUCCESS(status)) {
93                 acpi_gbl_all_gpes_initialized = TRUE;
94         }
95
96 unlock_and_exit:
97         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
98
99         return_ACPI_STATUS(status);
100 }
101
102 ACPI_EXPORT_SYMBOL(acpi_update_all_gpes)
103
104 /*******************************************************************************
105  *
106  * FUNCTION:    acpi_enable_gpe
107  *
108  * PARAMETERS:  gpe_device      - Parent GPE Device. NULL for GPE0/GPE1
109  *              gpe_number      - GPE level within the GPE block
110  *
111  * RETURN:      Status
112  *
113  * DESCRIPTION: Add a reference to a GPE. On the first reference, the GPE is
114  *              hardware-enabled.
115  *
116  ******************************************************************************/
117
118 acpi_status acpi_enable_gpe(acpi_handle gpe_device, u32 gpe_number)
119 {
120         acpi_status status = AE_BAD_PARAMETER;
121         struct acpi_gpe_event_info *gpe_event_info;
122         acpi_cpu_flags flags;
123
124         ACPI_FUNCTION_TRACE(acpi_enable_gpe);
125
126         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
127
128         /* Ensure that we have a valid GPE number */
129
130         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
131         if (gpe_event_info) {
132                 status = acpi_ev_add_gpe_reference(gpe_event_info);
133         }
134
135         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
136         return_ACPI_STATUS(status);
137 }
138 ACPI_EXPORT_SYMBOL(acpi_enable_gpe)
139
140 /*******************************************************************************
141  *
142  * FUNCTION:    acpi_disable_gpe
143  *
144  * PARAMETERS:  gpe_device      - Parent GPE Device. NULL for GPE0/GPE1
145  *              gpe_number      - GPE level within the GPE block
146  *
147  * RETURN:      Status
148  *
149  * DESCRIPTION: Remove a reference to a GPE. When the last reference is
150  *              removed, only then is the GPE disabled (for runtime GPEs), or
151  *              the GPE mask bit disabled (for wake GPEs)
152  *
153  ******************************************************************************/
154
155 acpi_status acpi_disable_gpe(acpi_handle gpe_device, u32 gpe_number)
156 {
157         acpi_status status = AE_BAD_PARAMETER;
158         struct acpi_gpe_event_info *gpe_event_info;
159         acpi_cpu_flags flags;
160
161         ACPI_FUNCTION_TRACE(acpi_disable_gpe);
162
163         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
164
165         /* Ensure that we have a valid GPE number */
166
167         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
168         if (gpe_event_info) {
169                 status = acpi_ev_remove_gpe_reference(gpe_event_info) ;
170         }
171
172         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
173         return_ACPI_STATUS(status);
174 }
175 ACPI_EXPORT_SYMBOL(acpi_disable_gpe)
176
177
178 /*******************************************************************************
179  *
180  * FUNCTION:    acpi_setup_gpe_for_wake
181  *
182  * PARAMETERS:  wake_device         - Device associated with the GPE (via _PRW)
183  *              gpe_device          - Parent GPE Device. NULL for GPE0/GPE1
184  *              gpe_number          - GPE level within the GPE block
185  *
186  * RETURN:      Status
187  *
188  * DESCRIPTION: Mark a GPE as having the ability to wake the system. This
189  *              interface is intended to be used as the host executes the
190  *              _PRW methods (Power Resources for Wake) in the system tables.
191  *              Each _PRW appears under a Device Object (The wake_device), and
192  *              contains the info for the wake GPE associated with the
193  *              wake_device.
194  *
195  ******************************************************************************/
196 acpi_status
197 acpi_setup_gpe_for_wake(acpi_handle wake_device,
198                         acpi_handle gpe_device, u32 gpe_number)
199 {
200         acpi_status status = AE_BAD_PARAMETER;
201         struct acpi_gpe_event_info *gpe_event_info;
202         struct acpi_namespace_node *device_node;
203         struct acpi_gpe_notify_object *notify_object;
204         acpi_cpu_flags flags;
205         u8 gpe_dispatch_mask;
206
207         ACPI_FUNCTION_TRACE(acpi_setup_gpe_for_wake);
208
209         /* Parameter Validation */
210
211         if (!wake_device) {
212                 /*
213                  * By forcing wake_device to be valid, we automatically enable the
214                  * implicit notify feature on all hosts.
215                  */
216                 return_ACPI_STATUS(AE_BAD_PARAMETER);
217         }
218
219         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
220
221         /* Ensure that we have a valid GPE number */
222
223         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
224         if (!gpe_event_info) {
225                 goto unlock_and_exit;
226         }
227
228         if (wake_device == ACPI_ROOT_OBJECT) {
229                 goto out;
230         }
231
232         /*
233          * If there is no method or handler for this GPE, then the
234          * wake_device will be notified whenever this GPE fires (aka
235          * "implicit notify") Note: The GPE is assumed to be
236          * level-triggered (for windows compatibility).
237          */
238         gpe_dispatch_mask = gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK;
239         if (gpe_dispatch_mask != ACPI_GPE_DISPATCH_NONE
240             && gpe_dispatch_mask != ACPI_GPE_DISPATCH_NOTIFY) {
241                 goto out;
242         }
243
244         /* Validate wake_device is of type Device */
245
246         device_node = ACPI_CAST_PTR(struct acpi_namespace_node, wake_device);
247         if (device_node->type != ACPI_TYPE_DEVICE) {
248                 goto unlock_and_exit;
249         }
250
251         if (gpe_dispatch_mask == ACPI_GPE_DISPATCH_NONE) {
252                 gpe_event_info->flags = (ACPI_GPE_DISPATCH_NOTIFY |
253                                          ACPI_GPE_LEVEL_TRIGGERED);
254                 gpe_event_info->dispatch.device.node = device_node;
255                 gpe_event_info->dispatch.device.next = NULL;
256         } else {
257                 /* There are multiple devices to notify implicitly. */
258
259                 notify_object = ACPI_ALLOCATE_ZEROED(sizeof(*notify_object));
260                 if (!notify_object) {
261                         status = AE_NO_MEMORY;
262                         goto unlock_and_exit;
263                 }
264
265                 notify_object->node = device_node;
266                 notify_object->next = gpe_event_info->dispatch.device.next;
267                 gpe_event_info->dispatch.device.next = notify_object;
268         }
269
270  out:
271         gpe_event_info->flags |= ACPI_GPE_CAN_WAKE;
272         status = AE_OK;
273
274  unlock_and_exit:
275         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
276         return_ACPI_STATUS(status);
277 }
278 ACPI_EXPORT_SYMBOL(acpi_setup_gpe_for_wake)
279
280 /*******************************************************************************
281  *
282  * FUNCTION:    acpi_set_gpe_wake_mask
283  *
284  * PARAMETERS:  gpe_device      - Parent GPE Device. NULL for GPE0/GPE1
285  *              gpe_number      - GPE level within the GPE block
286  *              Action          - Enable or Disable
287  *
288  * RETURN:      Status
289  *
290  * DESCRIPTION: Set or clear the GPE's wakeup enable mask bit. The GPE must
291  *              already be marked as a WAKE GPE.
292  *
293  ******************************************************************************/
294
295 acpi_status acpi_set_gpe_wake_mask(acpi_handle gpe_device, u32 gpe_number, u8 action)
296 {
297         acpi_status status = AE_OK;
298         struct acpi_gpe_event_info *gpe_event_info;
299         struct acpi_gpe_register_info *gpe_register_info;
300         acpi_cpu_flags flags;
301         u32 register_bit;
302
303         ACPI_FUNCTION_TRACE(acpi_set_gpe_wake_mask);
304
305         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
306
307         /*
308          * Ensure that we have a valid GPE number and that this GPE is in
309          * fact a wake GPE
310          */
311         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
312         if (!gpe_event_info) {
313                 status = AE_BAD_PARAMETER;
314                 goto unlock_and_exit;
315         }
316
317         if (!(gpe_event_info->flags & ACPI_GPE_CAN_WAKE)) {
318                 status = AE_TYPE;
319                 goto unlock_and_exit;
320         }
321
322         gpe_register_info = gpe_event_info->register_info;
323         if (!gpe_register_info) {
324                 status = AE_NOT_EXIST;
325                 goto unlock_and_exit;
326         }
327
328         register_bit =
329             acpi_hw_get_gpe_register_bit(gpe_event_info, gpe_register_info);
330
331         /* Perform the action */
332
333         switch (action) {
334         case ACPI_GPE_ENABLE:
335                 ACPI_SET_BIT(gpe_register_info->enable_for_wake,
336                              (u8)register_bit);
337                 break;
338
339         case ACPI_GPE_DISABLE:
340                 ACPI_CLEAR_BIT(gpe_register_info->enable_for_wake,
341                                (u8)register_bit);
342                 break;
343
344         default:
345                 ACPI_ERROR((AE_INFO, "%u, Invalid action", action));
346                 status = AE_BAD_PARAMETER;
347                 break;
348         }
349
350 unlock_and_exit:
351         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
352         return_ACPI_STATUS(status);
353 }
354
355 ACPI_EXPORT_SYMBOL(acpi_set_gpe_wake_mask)
356
357 /*******************************************************************************
358  *
359  * FUNCTION:    acpi_clear_gpe
360  *
361  * PARAMETERS:  gpe_device      - Parent GPE Device. NULL for GPE0/GPE1
362  *              gpe_number      - GPE level within the GPE block
363  *
364  * RETURN:      Status
365  *
366  * DESCRIPTION: Clear an ACPI event (general purpose)
367  *
368  ******************************************************************************/
369 acpi_status acpi_clear_gpe(acpi_handle gpe_device, u32 gpe_number)
370 {
371         acpi_status status = AE_OK;
372         struct acpi_gpe_event_info *gpe_event_info;
373         acpi_cpu_flags flags;
374
375         ACPI_FUNCTION_TRACE(acpi_clear_gpe);
376
377         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
378
379         /* Ensure that we have a valid GPE number */
380
381         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
382         if (!gpe_event_info) {
383                 status = AE_BAD_PARAMETER;
384                 goto unlock_and_exit;
385         }
386
387         status = acpi_hw_clear_gpe(gpe_event_info);
388
389       unlock_and_exit:
390         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
391         return_ACPI_STATUS(status);
392 }
393
394 ACPI_EXPORT_SYMBOL(acpi_clear_gpe)
395
396 /*******************************************************************************
397  *
398  * FUNCTION:    acpi_get_gpe_status
399  *
400  * PARAMETERS:  gpe_device      - Parent GPE Device. NULL for GPE0/GPE1
401  *              gpe_number      - GPE level within the GPE block
402  *              event_status    - Where the current status of the event will
403  *                                be returned
404  *
405  * RETURN:      Status
406  *
407  * DESCRIPTION: Get the current status of a GPE (signalled/not_signalled)
408  *
409  ******************************************************************************/
410 acpi_status
411 acpi_get_gpe_status(acpi_handle gpe_device,
412                     u32 gpe_number, acpi_event_status *event_status)
413 {
414         acpi_status status = AE_OK;
415         struct acpi_gpe_event_info *gpe_event_info;
416         acpi_cpu_flags flags;
417
418         ACPI_FUNCTION_TRACE(acpi_get_gpe_status);
419
420         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
421
422         /* Ensure that we have a valid GPE number */
423
424         gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
425         if (!gpe_event_info) {
426                 status = AE_BAD_PARAMETER;
427                 goto unlock_and_exit;
428         }
429
430         /* Obtain status on the requested GPE number */
431
432         status = acpi_hw_get_gpe_status(gpe_event_info, event_status);
433
434         if (gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK)
435                 *event_status |= ACPI_EVENT_FLAG_HANDLE;
436
437       unlock_and_exit:
438         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
439         return_ACPI_STATUS(status);
440 }
441
442 ACPI_EXPORT_SYMBOL(acpi_get_gpe_status)
443
444 /******************************************************************************
445  *
446  * FUNCTION:    acpi_disable_all_gpes
447  *
448  * PARAMETERS:  None
449  *
450  * RETURN:      Status
451  *
452  * DESCRIPTION: Disable and clear all GPEs in all GPE blocks
453  *
454  ******************************************************************************/
455
456 acpi_status acpi_disable_all_gpes(void)
457 {
458         acpi_status status;
459
460         ACPI_FUNCTION_TRACE(acpi_disable_all_gpes);
461
462         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
463         if (ACPI_FAILURE(status)) {
464                 return_ACPI_STATUS(status);
465         }
466
467         status = acpi_hw_disable_all_gpes();
468         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
469
470         return_ACPI_STATUS(status);
471 }
472
473 ACPI_EXPORT_SYMBOL(acpi_disable_all_gpes)
474
475 /******************************************************************************
476  *
477  * FUNCTION:    acpi_enable_all_runtime_gpes
478  *
479  * PARAMETERS:  None
480  *
481  * RETURN:      Status
482  *
483  * DESCRIPTION: Enable all "runtime" GPEs, in all GPE blocks
484  *
485  ******************************************************************************/
486
487 acpi_status acpi_enable_all_runtime_gpes(void)
488 {
489         acpi_status status;
490
491         ACPI_FUNCTION_TRACE(acpi_enable_all_runtime_gpes);
492
493         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
494         if (ACPI_FAILURE(status)) {
495                 return_ACPI_STATUS(status);
496         }
497
498         status = acpi_hw_enable_all_runtime_gpes();
499         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
500
501         return_ACPI_STATUS(status);
502 }
503
504 ACPI_EXPORT_SYMBOL(acpi_enable_all_runtime_gpes)
505
506 /*******************************************************************************
507  *
508  * FUNCTION:    acpi_install_gpe_block
509  *
510  * PARAMETERS:  gpe_device          - Handle to the parent GPE Block Device
511  *              gpe_block_address   - Address and space_iD
512  *              register_count      - Number of GPE register pairs in the block
513  *              interrupt_number    - H/W interrupt for the block
514  *
515  * RETURN:      Status
516  *
517  * DESCRIPTION: Create and Install a block of GPE registers. The GPEs are not
518  *              enabled here.
519  *
520  ******************************************************************************/
521 acpi_status
522 acpi_install_gpe_block(acpi_handle gpe_device,
523                        struct acpi_generic_address *gpe_block_address,
524                        u32 register_count, u32 interrupt_number)
525 {
526         acpi_status status;
527         union acpi_operand_object *obj_desc;
528         struct acpi_namespace_node *node;
529         struct acpi_gpe_block_info *gpe_block;
530
531         ACPI_FUNCTION_TRACE(acpi_install_gpe_block);
532
533         if ((!gpe_device) || (!gpe_block_address) || (!register_count)) {
534                 return_ACPI_STATUS(AE_BAD_PARAMETER);
535         }
536
537         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
538         if (ACPI_FAILURE(status)) {
539                 return (status);
540         }
541
542         node = acpi_ns_validate_handle(gpe_device);
543         if (!node) {
544                 status = AE_BAD_PARAMETER;
545                 goto unlock_and_exit;
546         }
547
548         /*
549          * For user-installed GPE Block Devices, the gpe_block_base_number
550          * is always zero
551          */
552         status =
553             acpi_ev_create_gpe_block(node, gpe_block_address, register_count, 0,
554                                      interrupt_number, &gpe_block);
555         if (ACPI_FAILURE(status)) {
556                 goto unlock_and_exit;
557         }
558
559         /* Install block in the device_object attached to the node */
560
561         obj_desc = acpi_ns_get_attached_object(node);
562         if (!obj_desc) {
563
564                 /*
565                  * No object, create a new one (Device nodes do not always have
566                  * an attached object)
567                  */
568                 obj_desc = acpi_ut_create_internal_object(ACPI_TYPE_DEVICE);
569                 if (!obj_desc) {
570                         status = AE_NO_MEMORY;
571                         goto unlock_and_exit;
572                 }
573
574                 status =
575                     acpi_ns_attach_object(node, obj_desc, ACPI_TYPE_DEVICE);
576
577                 /* Remove local reference to the object */
578
579                 acpi_ut_remove_reference(obj_desc);
580
581                 if (ACPI_FAILURE(status)) {
582                         goto unlock_and_exit;
583                 }
584         }
585
586         /* Now install the GPE block in the device_object */
587
588         obj_desc->device.gpe_block = gpe_block;
589
590       unlock_and_exit:
591         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
592         return_ACPI_STATUS(status);
593 }
594
595 ACPI_EXPORT_SYMBOL(acpi_install_gpe_block)
596
597 /*******************************************************************************
598  *
599  * FUNCTION:    acpi_remove_gpe_block
600  *
601  * PARAMETERS:  gpe_device          - Handle to the parent GPE Block Device
602  *
603  * RETURN:      Status
604  *
605  * DESCRIPTION: Remove a previously installed block of GPE registers
606  *
607  ******************************************************************************/
608 acpi_status acpi_remove_gpe_block(acpi_handle gpe_device)
609 {
610         union acpi_operand_object *obj_desc;
611         acpi_status status;
612         struct acpi_namespace_node *node;
613
614         ACPI_FUNCTION_TRACE(acpi_remove_gpe_block);
615
616         if (!gpe_device) {
617                 return_ACPI_STATUS(AE_BAD_PARAMETER);
618         }
619
620         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
621         if (ACPI_FAILURE(status)) {
622                 return (status);
623         }
624
625         node = acpi_ns_validate_handle(gpe_device);
626         if (!node) {
627                 status = AE_BAD_PARAMETER;
628                 goto unlock_and_exit;
629         }
630
631         /* Get the device_object attached to the node */
632
633         obj_desc = acpi_ns_get_attached_object(node);
634         if (!obj_desc || !obj_desc->device.gpe_block) {
635                 return_ACPI_STATUS(AE_NULL_OBJECT);
636         }
637
638         /* Delete the GPE block (but not the device_object) */
639
640         status = acpi_ev_delete_gpe_block(obj_desc->device.gpe_block);
641         if (ACPI_SUCCESS(status)) {
642                 obj_desc->device.gpe_block = NULL;
643         }
644
645       unlock_and_exit:
646         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
647         return_ACPI_STATUS(status);
648 }
649
650 ACPI_EXPORT_SYMBOL(acpi_remove_gpe_block)
651
652 /*******************************************************************************
653  *
654  * FUNCTION:    acpi_get_gpe_device
655  *
656  * PARAMETERS:  Index               - System GPE index (0-current_gpe_count)
657  *              gpe_device          - Where the parent GPE Device is returned
658  *
659  * RETURN:      Status
660  *
661  * DESCRIPTION: Obtain the GPE device associated with the input index. A NULL
662  *              gpe device indicates that the gpe number is contained in one of
663  *              the FADT-defined gpe blocks. Otherwise, the GPE block device.
664  *
665  ******************************************************************************/
666 acpi_status
667 acpi_get_gpe_device(u32 index, acpi_handle *gpe_device)
668 {
669         struct acpi_gpe_device_info info;
670         acpi_status status;
671
672         ACPI_FUNCTION_TRACE(acpi_get_gpe_device);
673
674         if (!gpe_device) {
675                 return_ACPI_STATUS(AE_BAD_PARAMETER);
676         }
677
678         if (index >= acpi_current_gpe_count) {
679                 return_ACPI_STATUS(AE_NOT_EXIST);
680         }
681
682         /* Setup and walk the GPE list */
683
684         info.index = index;
685         info.status = AE_NOT_EXIST;
686         info.gpe_device = NULL;
687         info.next_block_base_index = 0;
688
689         status = acpi_ev_walk_gpe_list(acpi_ev_get_gpe_device, &info);
690         if (ACPI_FAILURE(status)) {
691                 return_ACPI_STATUS(status);
692         }
693
694         *gpe_device = ACPI_CAST_PTR(acpi_handle, info.gpe_device);
695         return_ACPI_STATUS(info.status);
696 }
697
698 ACPI_EXPORT_SYMBOL(acpi_get_gpe_device)
699 #endif                          /* !ACPI_REDUCED_HARDWARE */