xref: /openbmc/linux/drivers/acpi/acpica/evxfgpe.c (revision df2634f43f5106947f3735a0b61a6527a4b278cd)
1 /******************************************************************************
2  *
3  * Module Name: evxfgpe - External Interfaces for General Purpose Events (GPEs)
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2011, 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 <acpi/acpi.h>
45 #include "accommon.h"
46 #include "acevents.h"
47 #include "acnamesp.h"
48 
49 #define _COMPONENT          ACPI_EVENTS
50 ACPI_MODULE_NAME("evxfgpe")
51 
52 /******************************************************************************
53  *
54  * FUNCTION:    acpi_update_all_gpes
55  *
56  * PARAMETERS:  None
57  *
58  * RETURN:      Status
59  *
60  * DESCRIPTION: Complete GPE initialization and enable all GPEs that have
61  *              associated _Lxx or _Exx methods and are not pointed to by any
62  *              device _PRW methods (this indicates that these GPEs are
63  *              generally intended for system or device wakeup. Such GPEs
64  *              have to be enabled directly when the devices whose _PRW
65  *              methods point to them are set up for wakeup signaling.)
66  *
67  * NOTE: Should be called after any GPEs are added to the system. Primarily,
68  * after the system _PRW methods have been run, but also after a GPE Block
69  * Device has been added or if any new GPE methods have been added via a
70  * dynamic table load.
71  *
72  ******************************************************************************/
73 
74 acpi_status acpi_update_all_gpes(void)
75 {
76 	acpi_status status;
77 
78 	ACPI_FUNCTION_TRACE(acpi_update_all_gpes);
79 
80 	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
81 	if (ACPI_FAILURE(status)) {
82 		return_ACPI_STATUS(status);
83 	}
84 
85 	if (acpi_gbl_all_gpes_initialized) {
86 		goto unlock_and_exit;
87 	}
88 
89 	status = acpi_ev_walk_gpe_list(acpi_ev_initialize_gpe_block, NULL);
90 	if (ACPI_SUCCESS(status)) {
91 		acpi_gbl_all_gpes_initialized = TRUE;
92 	}
93 
94 unlock_and_exit:
95 	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
96 
97 	return_ACPI_STATUS(status);
98 }
99 
100 ACPI_EXPORT_SYMBOL(acpi_update_all_gpes)
101 
102 /*******************************************************************************
103  *
104  * FUNCTION:    acpi_enable_gpe
105  *
106  * PARAMETERS:  gpe_device      - Parent GPE Device. NULL for GPE0/GPE1
107  *              gpe_number      - GPE level within the GPE block
108  *
109  * RETURN:      Status
110  *
111  * DESCRIPTION: Add a reference to a GPE. On the first reference, the GPE is
112  *              hardware-enabled.
113  *
114  ******************************************************************************/
115 
116 acpi_status acpi_enable_gpe(acpi_handle gpe_device, u32 gpe_number)
117 {
118 	acpi_status status = AE_BAD_PARAMETER;
119 	struct acpi_gpe_event_info *gpe_event_info;
120 	acpi_cpu_flags flags;
121 
122 	ACPI_FUNCTION_TRACE(acpi_enable_gpe);
123 
124 	flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
125 
126 	/* Ensure that we have a valid GPE number */
127 
128 	gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
129 	if (gpe_event_info) {
130 		status = acpi_ev_add_gpe_reference(gpe_event_info);
131 	}
132 
133 	acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
134 	return_ACPI_STATUS(status);
135 }
136 ACPI_EXPORT_SYMBOL(acpi_enable_gpe)
137 
138 /*******************************************************************************
139  *
140  * FUNCTION:    acpi_disable_gpe
141  *
142  * PARAMETERS:  gpe_device      - Parent GPE Device. NULL for GPE0/GPE1
143  *              gpe_number      - GPE level within the GPE block
144  *
145  * RETURN:      Status
146  *
147  * DESCRIPTION: Remove a reference to a GPE. When the last reference is
148  *              removed, only then is the GPE disabled (for runtime GPEs), or
149  *              the GPE mask bit disabled (for wake GPEs)
150  *
151  ******************************************************************************/
152 
153 acpi_status acpi_disable_gpe(acpi_handle gpe_device, u32 gpe_number)
154 {
155 	acpi_status status = AE_BAD_PARAMETER;
156 	struct acpi_gpe_event_info *gpe_event_info;
157 	acpi_cpu_flags flags;
158 
159 	ACPI_FUNCTION_TRACE(acpi_disable_gpe);
160 
161 	flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
162 
163 	/* Ensure that we have a valid GPE number */
164 
165 	gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
166 	if (gpe_event_info) {
167 		status = acpi_ev_remove_gpe_reference(gpe_event_info) ;
168 	}
169 
170 	acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
171 	return_ACPI_STATUS(status);
172 }
173 ACPI_EXPORT_SYMBOL(acpi_disable_gpe)
174 
175 
176 /*******************************************************************************
177  *
178  * FUNCTION:    acpi_setup_gpe_for_wake
179  *
180  * PARAMETERS:  wake_device         - Device associated with the GPE (via _PRW)
181  *              gpe_device          - Parent GPE Device. NULL for GPE0/GPE1
182  *              gpe_number          - GPE level within the GPE block
183  *
184  * RETURN:      Status
185  *
186  * DESCRIPTION: Mark a GPE as having the ability to wake the system. This
187  *              interface is intended to be used as the host executes the
188  *              _PRW methods (Power Resources for Wake) in the system tables.
189  *              Each _PRW appears under a Device Object (The wake_device), and
190  *              contains the info for the wake GPE associated with the
191  *              wake_device.
192  *
193  ******************************************************************************/
194 acpi_status
195 acpi_setup_gpe_for_wake(acpi_handle wake_device,
196 			acpi_handle gpe_device, u32 gpe_number)
197 {
198 	acpi_status status = AE_BAD_PARAMETER;
199 	struct acpi_gpe_event_info *gpe_event_info;
200 	struct acpi_namespace_node *device_node;
201 	acpi_cpu_flags flags;
202 
203 	ACPI_FUNCTION_TRACE(acpi_setup_gpe_for_wake);
204 
205 	/* Parameter Validation */
206 
207 	if (!wake_device) {
208 		/*
209 		 * By forcing wake_device to be valid, we automatically enable the
210 		 * implicit notify feature on all hosts.
211 		 */
212 		return_ACPI_STATUS(AE_BAD_PARAMETER);
213 	}
214 
215 	flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
216 
217 	/* Ensure that we have a valid GPE number */
218 
219 	gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
220 	if (!gpe_event_info) {
221 		goto unlock_and_exit;
222 	}
223 
224 	/*
225 	 * If there is no method or handler for this GPE, then the
226 	 * wake_device will be notified whenever this GPE fires (aka
227 	 * "implicit notify") Note: The GPE is assumed to be
228 	 * level-triggered (for windows compatibility).
229 	 */
230 	if (((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
231 	      ACPI_GPE_DISPATCH_NONE) && (wake_device != ACPI_ROOT_OBJECT)) {
232 
233 		/* Validate wake_device is of type Device */
234 
235 		device_node = ACPI_CAST_PTR(struct acpi_namespace_node,
236 					    wake_device);
237 		if (device_node->type != ACPI_TYPE_DEVICE) {
238 			goto unlock_and_exit;
239 		}
240 		gpe_event_info->flags = (ACPI_GPE_DISPATCH_NOTIFY |
241 					 ACPI_GPE_LEVEL_TRIGGERED);
242 		gpe_event_info->dispatch.device_node = device_node;
243 	}
244 
245 	gpe_event_info->flags |= ACPI_GPE_CAN_WAKE;
246 	status = AE_OK;
247 
248  unlock_and_exit:
249 	acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
250 	return_ACPI_STATUS(status);
251 }
252 ACPI_EXPORT_SYMBOL(acpi_setup_gpe_for_wake)
253 
254 /*******************************************************************************
255  *
256  * FUNCTION:    acpi_set_gpe_wake_mask
257  *
258  * PARAMETERS:  gpe_device      - Parent GPE Device. NULL for GPE0/GPE1
259  *              gpe_number      - GPE level within the GPE block
260  *              Action          - Enable or Disable
261  *
262  * RETURN:      Status
263  *
264  * DESCRIPTION: Set or clear the GPE's wakeup enable mask bit. The GPE must
265  *              already be marked as a WAKE GPE.
266  *
267  ******************************************************************************/
268 
269 acpi_status acpi_set_gpe_wake_mask(acpi_handle gpe_device, u32 gpe_number, u8 action)
270 {
271 	acpi_status status = AE_OK;
272 	struct acpi_gpe_event_info *gpe_event_info;
273 	struct acpi_gpe_register_info *gpe_register_info;
274 	acpi_cpu_flags flags;
275 	u32 register_bit;
276 
277 	ACPI_FUNCTION_TRACE(acpi_set_gpe_wake_mask);
278 
279 	flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
280 
281 	/*
282 	 * Ensure that we have a valid GPE number and that this GPE is in
283 	 * fact a wake GPE
284 	 */
285 	gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
286 	if (!gpe_event_info) {
287 		status = AE_BAD_PARAMETER;
288 		goto unlock_and_exit;
289 	}
290 
291 	if (!(gpe_event_info->flags & ACPI_GPE_CAN_WAKE)) {
292 		status = AE_TYPE;
293 		goto unlock_and_exit;
294 	}
295 
296 	gpe_register_info = gpe_event_info->register_info;
297 	if (!gpe_register_info) {
298 		status = AE_NOT_EXIST;
299 		goto unlock_and_exit;
300 	}
301 
302 	register_bit =
303 	    acpi_hw_get_gpe_register_bit(gpe_event_info, gpe_register_info);
304 
305 	/* Perform the action */
306 
307 	switch (action) {
308 	case ACPI_GPE_ENABLE:
309 		ACPI_SET_BIT(gpe_register_info->enable_for_wake,
310 			     (u8)register_bit);
311 		break;
312 
313 	case ACPI_GPE_DISABLE:
314 		ACPI_CLEAR_BIT(gpe_register_info->enable_for_wake,
315 			       (u8)register_bit);
316 		break;
317 
318 	default:
319 		ACPI_ERROR((AE_INFO, "%u, Invalid action", action));
320 		status = AE_BAD_PARAMETER;
321 		break;
322 	}
323 
324 unlock_and_exit:
325 	acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
326 	return_ACPI_STATUS(status);
327 }
328 
329 ACPI_EXPORT_SYMBOL(acpi_set_gpe_wake_mask)
330 
331 /*******************************************************************************
332  *
333  * FUNCTION:    acpi_clear_gpe
334  *
335  * PARAMETERS:  gpe_device      - Parent GPE Device. NULL for GPE0/GPE1
336  *              gpe_number      - GPE level within the GPE block
337  *
338  * RETURN:      Status
339  *
340  * DESCRIPTION: Clear an ACPI event (general purpose)
341  *
342  ******************************************************************************/
343 acpi_status acpi_clear_gpe(acpi_handle gpe_device, u32 gpe_number)
344 {
345 	acpi_status status = AE_OK;
346 	struct acpi_gpe_event_info *gpe_event_info;
347 	acpi_cpu_flags flags;
348 
349 	ACPI_FUNCTION_TRACE(acpi_clear_gpe);
350 
351 	flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
352 
353 	/* Ensure that we have a valid GPE number */
354 
355 	gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
356 	if (!gpe_event_info) {
357 		status = AE_BAD_PARAMETER;
358 		goto unlock_and_exit;
359 	}
360 
361 	status = acpi_hw_clear_gpe(gpe_event_info);
362 
363       unlock_and_exit:
364 	acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
365 	return_ACPI_STATUS(status);
366 }
367 
368 ACPI_EXPORT_SYMBOL(acpi_clear_gpe)
369 
370 /*******************************************************************************
371  *
372  * FUNCTION:    acpi_get_gpe_status
373  *
374  * PARAMETERS:  gpe_device      - Parent GPE Device. NULL for GPE0/GPE1
375  *              gpe_number      - GPE level within the GPE block
376  *              event_status    - Where the current status of the event will
377  *                                be returned
378  *
379  * RETURN:      Status
380  *
381  * DESCRIPTION: Get the current status of a GPE (signalled/not_signalled)
382  *
383  ******************************************************************************/
384 acpi_status
385 acpi_get_gpe_status(acpi_handle gpe_device,
386 		    u32 gpe_number, acpi_event_status *event_status)
387 {
388 	acpi_status status = AE_OK;
389 	struct acpi_gpe_event_info *gpe_event_info;
390 	acpi_cpu_flags flags;
391 
392 	ACPI_FUNCTION_TRACE(acpi_get_gpe_status);
393 
394 	flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
395 
396 	/* Ensure that we have a valid GPE number */
397 
398 	gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
399 	if (!gpe_event_info) {
400 		status = AE_BAD_PARAMETER;
401 		goto unlock_and_exit;
402 	}
403 
404 	/* Obtain status on the requested GPE number */
405 
406 	status = acpi_hw_get_gpe_status(gpe_event_info, event_status);
407 
408 	if (gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK)
409 		*event_status |= ACPI_EVENT_FLAG_HANDLE;
410 
411       unlock_and_exit:
412 	acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
413 	return_ACPI_STATUS(status);
414 }
415 
416 ACPI_EXPORT_SYMBOL(acpi_get_gpe_status)
417 
418 /******************************************************************************
419  *
420  * FUNCTION:    acpi_disable_all_gpes
421  *
422  * PARAMETERS:  None
423  *
424  * RETURN:      Status
425  *
426  * DESCRIPTION: Disable and clear all GPEs in all GPE blocks
427  *
428  ******************************************************************************/
429 
430 acpi_status acpi_disable_all_gpes(void)
431 {
432 	acpi_status status;
433 
434 	ACPI_FUNCTION_TRACE(acpi_disable_all_gpes);
435 
436 	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
437 	if (ACPI_FAILURE(status)) {
438 		return_ACPI_STATUS(status);
439 	}
440 
441 	status = acpi_hw_disable_all_gpes();
442 	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
443 
444 	return_ACPI_STATUS(status);
445 }
446 
447 ACPI_EXPORT_SYMBOL(acpi_disable_all_gpes)
448 
449 /******************************************************************************
450  *
451  * FUNCTION:    acpi_enable_all_runtime_gpes
452  *
453  * PARAMETERS:  None
454  *
455  * RETURN:      Status
456  *
457  * DESCRIPTION: Enable all "runtime" GPEs, in all GPE blocks
458  *
459  ******************************************************************************/
460 
461 acpi_status acpi_enable_all_runtime_gpes(void)
462 {
463 	acpi_status status;
464 
465 	ACPI_FUNCTION_TRACE(acpi_enable_all_runtime_gpes);
466 
467 	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
468 	if (ACPI_FAILURE(status)) {
469 		return_ACPI_STATUS(status);
470 	}
471 
472 	status = acpi_hw_enable_all_runtime_gpes();
473 	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
474 
475 	return_ACPI_STATUS(status);
476 }
477 
478 ACPI_EXPORT_SYMBOL(acpi_enable_all_runtime_gpes)
479 
480 /*******************************************************************************
481  *
482  * FUNCTION:    acpi_install_gpe_block
483  *
484  * PARAMETERS:  gpe_device          - Handle to the parent GPE Block Device
485  *              gpe_block_address   - Address and space_iD
486  *              register_count      - Number of GPE register pairs in the block
487  *              interrupt_number    - H/W interrupt for the block
488  *
489  * RETURN:      Status
490  *
491  * DESCRIPTION: Create and Install a block of GPE registers. The GPEs are not
492  *              enabled here.
493  *
494  ******************************************************************************/
495 acpi_status
496 acpi_install_gpe_block(acpi_handle gpe_device,
497 		       struct acpi_generic_address *gpe_block_address,
498 		       u32 register_count, u32 interrupt_number)
499 {
500 	acpi_status status;
501 	union acpi_operand_object *obj_desc;
502 	struct acpi_namespace_node *node;
503 	struct acpi_gpe_block_info *gpe_block;
504 
505 	ACPI_FUNCTION_TRACE(acpi_install_gpe_block);
506 
507 	if ((!gpe_device) || (!gpe_block_address) || (!register_count)) {
508 		return_ACPI_STATUS(AE_BAD_PARAMETER);
509 	}
510 
511 	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
512 	if (ACPI_FAILURE(status)) {
513 		return (status);
514 	}
515 
516 	node = acpi_ns_validate_handle(gpe_device);
517 	if (!node) {
518 		status = AE_BAD_PARAMETER;
519 		goto unlock_and_exit;
520 	}
521 
522 	/*
523 	 * For user-installed GPE Block Devices, the gpe_block_base_number
524 	 * is always zero
525 	 */
526 	status =
527 	    acpi_ev_create_gpe_block(node, gpe_block_address, register_count, 0,
528 				     interrupt_number, &gpe_block);
529 	if (ACPI_FAILURE(status)) {
530 		goto unlock_and_exit;
531 	}
532 
533 	/* Install block in the device_object attached to the node */
534 
535 	obj_desc = acpi_ns_get_attached_object(node);
536 	if (!obj_desc) {
537 
538 		/*
539 		 * No object, create a new one (Device nodes do not always have
540 		 * an attached object)
541 		 */
542 		obj_desc = acpi_ut_create_internal_object(ACPI_TYPE_DEVICE);
543 		if (!obj_desc) {
544 			status = AE_NO_MEMORY;
545 			goto unlock_and_exit;
546 		}
547 
548 		status =
549 		    acpi_ns_attach_object(node, obj_desc, ACPI_TYPE_DEVICE);
550 
551 		/* Remove local reference to the object */
552 
553 		acpi_ut_remove_reference(obj_desc);
554 
555 		if (ACPI_FAILURE(status)) {
556 			goto unlock_and_exit;
557 		}
558 	}
559 
560 	/* Now install the GPE block in the device_object */
561 
562 	obj_desc->device.gpe_block = gpe_block;
563 
564       unlock_and_exit:
565 	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
566 	return_ACPI_STATUS(status);
567 }
568 
569 ACPI_EXPORT_SYMBOL(acpi_install_gpe_block)
570 
571 /*******************************************************************************
572  *
573  * FUNCTION:    acpi_remove_gpe_block
574  *
575  * PARAMETERS:  gpe_device          - Handle to the parent GPE Block Device
576  *
577  * RETURN:      Status
578  *
579  * DESCRIPTION: Remove a previously installed block of GPE registers
580  *
581  ******************************************************************************/
582 acpi_status acpi_remove_gpe_block(acpi_handle gpe_device)
583 {
584 	union acpi_operand_object *obj_desc;
585 	acpi_status status;
586 	struct acpi_namespace_node *node;
587 
588 	ACPI_FUNCTION_TRACE(acpi_remove_gpe_block);
589 
590 	if (!gpe_device) {
591 		return_ACPI_STATUS(AE_BAD_PARAMETER);
592 	}
593 
594 	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
595 	if (ACPI_FAILURE(status)) {
596 		return (status);
597 	}
598 
599 	node = acpi_ns_validate_handle(gpe_device);
600 	if (!node) {
601 		status = AE_BAD_PARAMETER;
602 		goto unlock_and_exit;
603 	}
604 
605 	/* Get the device_object attached to the node */
606 
607 	obj_desc = acpi_ns_get_attached_object(node);
608 	if (!obj_desc || !obj_desc->device.gpe_block) {
609 		return_ACPI_STATUS(AE_NULL_OBJECT);
610 	}
611 
612 	/* Delete the GPE block (but not the device_object) */
613 
614 	status = acpi_ev_delete_gpe_block(obj_desc->device.gpe_block);
615 	if (ACPI_SUCCESS(status)) {
616 		obj_desc->device.gpe_block = NULL;
617 	}
618 
619       unlock_and_exit:
620 	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
621 	return_ACPI_STATUS(status);
622 }
623 
624 ACPI_EXPORT_SYMBOL(acpi_remove_gpe_block)
625 
626 /*******************************************************************************
627  *
628  * FUNCTION:    acpi_get_gpe_device
629  *
630  * PARAMETERS:  Index               - System GPE index (0-current_gpe_count)
631  *              gpe_device          - Where the parent GPE Device is returned
632  *
633  * RETURN:      Status
634  *
635  * DESCRIPTION: Obtain the GPE device associated with the input index. A NULL
636  *              gpe device indicates that the gpe number is contained in one of
637  *              the FADT-defined gpe blocks. Otherwise, the GPE block device.
638  *
639  ******************************************************************************/
640 acpi_status
641 acpi_get_gpe_device(u32 index, acpi_handle *gpe_device)
642 {
643 	struct acpi_gpe_device_info info;
644 	acpi_status status;
645 
646 	ACPI_FUNCTION_TRACE(acpi_get_gpe_device);
647 
648 	if (!gpe_device) {
649 		return_ACPI_STATUS(AE_BAD_PARAMETER);
650 	}
651 
652 	if (index >= acpi_current_gpe_count) {
653 		return_ACPI_STATUS(AE_NOT_EXIST);
654 	}
655 
656 	/* Setup and walk the GPE list */
657 
658 	info.index = index;
659 	info.status = AE_NOT_EXIST;
660 	info.gpe_device = NULL;
661 	info.next_block_base_index = 0;
662 
663 	status = acpi_ev_walk_gpe_list(acpi_ev_get_gpe_device, &info);
664 	if (ACPI_FAILURE(status)) {
665 		return_ACPI_STATUS(status);
666 	}
667 
668 	*gpe_device = ACPI_CAST_PTR(acpi_handle, info.gpe_device);
669 	return_ACPI_STATUS(info.status);
670 }
671 
672 ACPI_EXPORT_SYMBOL(acpi_get_gpe_device)
673