xref: /linux/drivers/acpi/acpica/evxfgpe.c (revision 08ec212c0f92cbf30e3ecc7349f18151714041d6)
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;
201 	struct acpi_gpe_event_info *gpe_event_info;
202 	struct acpi_namespace_node *device_node;
203 	struct acpi_gpe_notify_info *notify;
204 	struct acpi_gpe_notify_info *new_notify;
205 	acpi_cpu_flags flags;
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 	/* Handle root object case */
220 
221 	if (wake_device == ACPI_ROOT_OBJECT) {
222 		device_node = acpi_gbl_root_node;
223 	} else {
224 		device_node = ACPI_CAST_PTR(struct acpi_namespace_node, wake_device);
225 	}
226 
227 	/* Validate WakeDevice is of type Device */
228 
229 	if (device_node->type != ACPI_TYPE_DEVICE) {
230 		return_ACPI_STATUS (AE_BAD_PARAMETER);
231 	}
232 
233 	/*
234 	 * Allocate a new notify object up front, in case it is needed.
235 	 * Memory allocation while holding a spinlock is a big no-no
236 	 * on some hosts.
237 	 */
238 	new_notify = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_gpe_notify_info));
239 	if (!new_notify) {
240 		return_ACPI_STATUS(AE_NO_MEMORY);
241 	}
242 
243 	flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
244 
245 	/* Ensure that we have a valid GPE number */
246 
247 	gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
248 	if (!gpe_event_info) {
249 		status = AE_BAD_PARAMETER;
250 		goto unlock_and_exit;
251 	}
252 
253 	/*
254 	 * If there is no method or handler for this GPE, then the
255 	 * wake_device will be notified whenever this GPE fires. This is
256 	 * known as an "implicit notify". Note: The GPE is assumed to be
257 	 * level-triggered (for windows compatibility).
258 	 */
259 	if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
260 	    ACPI_GPE_DISPATCH_NONE) {
261 		/*
262 		 * This is the first device for implicit notify on this GPE.
263 		 * Just set the flags here, and enter the NOTIFY block below.
264 		 */
265 		gpe_event_info->flags =
266 		    (ACPI_GPE_DISPATCH_NOTIFY | ACPI_GPE_LEVEL_TRIGGERED);
267 	}
268 
269 	/*
270 	 * If we already have an implicit notify on this GPE, add
271 	 * this device to the notify list.
272 	 */
273 	if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
274 	    ACPI_GPE_DISPATCH_NOTIFY) {
275 
276 		/* Ensure that the device is not already in the list */
277 
278 		notify = gpe_event_info->dispatch.notify_list;
279 		while (notify) {
280 			if (notify->device_node == device_node) {
281 				status = AE_ALREADY_EXISTS;
282 				goto unlock_and_exit;
283 			}
284 			notify = notify->next;
285 		}
286 
287 		/* Add this device to the notify list for this GPE */
288 
289 		new_notify->device_node = device_node;
290 		new_notify->next = gpe_event_info->dispatch.notify_list;
291 		gpe_event_info->dispatch.notify_list = new_notify;
292 		new_notify = NULL;
293 	}
294 
295 	/* Mark the GPE as a possible wake event */
296 
297 	gpe_event_info->flags |= ACPI_GPE_CAN_WAKE;
298 	status = AE_OK;
299 
300 unlock_and_exit:
301 	acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
302 
303 	/* Delete the notify object if it was not used above */
304 
305 	if (new_notify) {
306 		ACPI_FREE(new_notify);
307 	}
308 	return_ACPI_STATUS(status);
309 }
310 ACPI_EXPORT_SYMBOL(acpi_setup_gpe_for_wake)
311 
312 /*******************************************************************************
313  *
314  * FUNCTION:    acpi_set_gpe_wake_mask
315  *
316  * PARAMETERS:  gpe_device      - Parent GPE Device. NULL for GPE0/GPE1
317  *              gpe_number      - GPE level within the GPE block
318  *              action              - Enable or Disable
319  *
320  * RETURN:      Status
321  *
322  * DESCRIPTION: Set or clear the GPE's wakeup enable mask bit. The GPE must
323  *              already be marked as a WAKE GPE.
324  *
325  ******************************************************************************/
326 
327 acpi_status acpi_set_gpe_wake_mask(acpi_handle gpe_device, u32 gpe_number, u8 action)
328 {
329 	acpi_status status = AE_OK;
330 	struct acpi_gpe_event_info *gpe_event_info;
331 	struct acpi_gpe_register_info *gpe_register_info;
332 	acpi_cpu_flags flags;
333 	u32 register_bit;
334 
335 	ACPI_FUNCTION_TRACE(acpi_set_gpe_wake_mask);
336 
337 	flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
338 
339 	/*
340 	 * Ensure that we have a valid GPE number and that this GPE is in
341 	 * fact a wake GPE
342 	 */
343 	gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
344 	if (!gpe_event_info) {
345 		status = AE_BAD_PARAMETER;
346 		goto unlock_and_exit;
347 	}
348 
349 	if (!(gpe_event_info->flags & ACPI_GPE_CAN_WAKE)) {
350 		status = AE_TYPE;
351 		goto unlock_and_exit;
352 	}
353 
354 	gpe_register_info = gpe_event_info->register_info;
355 	if (!gpe_register_info) {
356 		status = AE_NOT_EXIST;
357 		goto unlock_and_exit;
358 	}
359 
360 	register_bit = acpi_hw_get_gpe_register_bit(gpe_event_info);
361 
362 	/* Perform the action */
363 
364 	switch (action) {
365 	case ACPI_GPE_ENABLE:
366 		ACPI_SET_BIT(gpe_register_info->enable_for_wake,
367 			     (u8)register_bit);
368 		break;
369 
370 	case ACPI_GPE_DISABLE:
371 		ACPI_CLEAR_BIT(gpe_register_info->enable_for_wake,
372 			       (u8)register_bit);
373 		break;
374 
375 	default:
376 		ACPI_ERROR((AE_INFO, "%u, Invalid action", action));
377 		status = AE_BAD_PARAMETER;
378 		break;
379 	}
380 
381 unlock_and_exit:
382 	acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
383 	return_ACPI_STATUS(status);
384 }
385 
386 ACPI_EXPORT_SYMBOL(acpi_set_gpe_wake_mask)
387 
388 /*******************************************************************************
389  *
390  * FUNCTION:    acpi_clear_gpe
391  *
392  * PARAMETERS:  gpe_device      - Parent GPE Device. NULL for GPE0/GPE1
393  *              gpe_number      - GPE level within the GPE block
394  *
395  * RETURN:      Status
396  *
397  * DESCRIPTION: Clear an ACPI event (general purpose)
398  *
399  ******************************************************************************/
400 acpi_status acpi_clear_gpe(acpi_handle gpe_device, u32 gpe_number)
401 {
402 	acpi_status status = AE_OK;
403 	struct acpi_gpe_event_info *gpe_event_info;
404 	acpi_cpu_flags flags;
405 
406 	ACPI_FUNCTION_TRACE(acpi_clear_gpe);
407 
408 	flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
409 
410 	/* Ensure that we have a valid GPE number */
411 
412 	gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
413 	if (!gpe_event_info) {
414 		status = AE_BAD_PARAMETER;
415 		goto unlock_and_exit;
416 	}
417 
418 	status = acpi_hw_clear_gpe(gpe_event_info);
419 
420       unlock_and_exit:
421 	acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
422 	return_ACPI_STATUS(status);
423 }
424 
425 ACPI_EXPORT_SYMBOL(acpi_clear_gpe)
426 
427 /*******************************************************************************
428  *
429  * FUNCTION:    acpi_get_gpe_status
430  *
431  * PARAMETERS:  gpe_device      - Parent GPE Device. NULL for GPE0/GPE1
432  *              gpe_number      - GPE level within the GPE block
433  *              event_status    - Where the current status of the event will
434  *                                be returned
435  *
436  * RETURN:      Status
437  *
438  * DESCRIPTION: Get the current status of a GPE (signalled/not_signalled)
439  *
440  ******************************************************************************/
441 acpi_status
442 acpi_get_gpe_status(acpi_handle gpe_device,
443 		    u32 gpe_number, acpi_event_status *event_status)
444 {
445 	acpi_status status = AE_OK;
446 	struct acpi_gpe_event_info *gpe_event_info;
447 	acpi_cpu_flags flags;
448 
449 	ACPI_FUNCTION_TRACE(acpi_get_gpe_status);
450 
451 	flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
452 
453 	/* Ensure that we have a valid GPE number */
454 
455 	gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
456 	if (!gpe_event_info) {
457 		status = AE_BAD_PARAMETER;
458 		goto unlock_and_exit;
459 	}
460 
461 	/* Obtain status on the requested GPE number */
462 
463 	status = acpi_hw_get_gpe_status(gpe_event_info, event_status);
464 
465 	if (gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK)
466 		*event_status |= ACPI_EVENT_FLAG_HANDLE;
467 
468       unlock_and_exit:
469 	acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
470 	return_ACPI_STATUS(status);
471 }
472 
473 ACPI_EXPORT_SYMBOL(acpi_get_gpe_status)
474 
475 /******************************************************************************
476  *
477  * FUNCTION:    acpi_disable_all_gpes
478  *
479  * PARAMETERS:  None
480  *
481  * RETURN:      Status
482  *
483  * DESCRIPTION: Disable and clear all GPEs in all GPE blocks
484  *
485  ******************************************************************************/
486 
487 acpi_status acpi_disable_all_gpes(void)
488 {
489 	acpi_status status;
490 
491 	ACPI_FUNCTION_TRACE(acpi_disable_all_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_disable_all_gpes();
499 	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
500 
501 	return_ACPI_STATUS(status);
502 }
503 
504 ACPI_EXPORT_SYMBOL(acpi_disable_all_gpes)
505 
506 /******************************************************************************
507  *
508  * FUNCTION:    acpi_enable_all_runtime_gpes
509  *
510  * PARAMETERS:  None
511  *
512  * RETURN:      Status
513  *
514  * DESCRIPTION: Enable all "runtime" GPEs, in all GPE blocks
515  *
516  ******************************************************************************/
517 
518 acpi_status acpi_enable_all_runtime_gpes(void)
519 {
520 	acpi_status status;
521 
522 	ACPI_FUNCTION_TRACE(acpi_enable_all_runtime_gpes);
523 
524 	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
525 	if (ACPI_FAILURE(status)) {
526 		return_ACPI_STATUS(status);
527 	}
528 
529 	status = acpi_hw_enable_all_runtime_gpes();
530 	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
531 
532 	return_ACPI_STATUS(status);
533 }
534 
535 ACPI_EXPORT_SYMBOL(acpi_enable_all_runtime_gpes)
536 
537 /*******************************************************************************
538  *
539  * FUNCTION:    acpi_install_gpe_block
540  *
541  * PARAMETERS:  gpe_device          - Handle to the parent GPE Block Device
542  *              gpe_block_address   - Address and space_ID
543  *              register_count      - Number of GPE register pairs in the block
544  *              interrupt_number    - H/W interrupt for the block
545  *
546  * RETURN:      Status
547  *
548  * DESCRIPTION: Create and Install a block of GPE registers. The GPEs are not
549  *              enabled here.
550  *
551  ******************************************************************************/
552 acpi_status
553 acpi_install_gpe_block(acpi_handle gpe_device,
554 		       struct acpi_generic_address *gpe_block_address,
555 		       u32 register_count, u32 interrupt_number)
556 {
557 	acpi_status status;
558 	union acpi_operand_object *obj_desc;
559 	struct acpi_namespace_node *node;
560 	struct acpi_gpe_block_info *gpe_block;
561 
562 	ACPI_FUNCTION_TRACE(acpi_install_gpe_block);
563 
564 	if ((!gpe_device) || (!gpe_block_address) || (!register_count)) {
565 		return_ACPI_STATUS(AE_BAD_PARAMETER);
566 	}
567 
568 	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
569 	if (ACPI_FAILURE(status)) {
570 		return (status);
571 	}
572 
573 	node = acpi_ns_validate_handle(gpe_device);
574 	if (!node) {
575 		status = AE_BAD_PARAMETER;
576 		goto unlock_and_exit;
577 	}
578 
579 	/*
580 	 * For user-installed GPE Block Devices, the gpe_block_base_number
581 	 * is always zero
582 	 */
583 	status =
584 	    acpi_ev_create_gpe_block(node, gpe_block_address, register_count, 0,
585 				     interrupt_number, &gpe_block);
586 	if (ACPI_FAILURE(status)) {
587 		goto unlock_and_exit;
588 	}
589 
590 	/* Install block in the device_object attached to the node */
591 
592 	obj_desc = acpi_ns_get_attached_object(node);
593 	if (!obj_desc) {
594 
595 		/*
596 		 * No object, create a new one (Device nodes do not always have
597 		 * an attached object)
598 		 */
599 		obj_desc = acpi_ut_create_internal_object(ACPI_TYPE_DEVICE);
600 		if (!obj_desc) {
601 			status = AE_NO_MEMORY;
602 			goto unlock_and_exit;
603 		}
604 
605 		status =
606 		    acpi_ns_attach_object(node, obj_desc, ACPI_TYPE_DEVICE);
607 
608 		/* Remove local reference to the object */
609 
610 		acpi_ut_remove_reference(obj_desc);
611 
612 		if (ACPI_FAILURE(status)) {
613 			goto unlock_and_exit;
614 		}
615 	}
616 
617 	/* Now install the GPE block in the device_object */
618 
619 	obj_desc->device.gpe_block = gpe_block;
620 
621       unlock_and_exit:
622 	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
623 	return_ACPI_STATUS(status);
624 }
625 
626 ACPI_EXPORT_SYMBOL(acpi_install_gpe_block)
627 
628 /*******************************************************************************
629  *
630  * FUNCTION:    acpi_remove_gpe_block
631  *
632  * PARAMETERS:  gpe_device          - Handle to the parent GPE Block Device
633  *
634  * RETURN:      Status
635  *
636  * DESCRIPTION: Remove a previously installed block of GPE registers
637  *
638  ******************************************************************************/
639 acpi_status acpi_remove_gpe_block(acpi_handle gpe_device)
640 {
641 	union acpi_operand_object *obj_desc;
642 	acpi_status status;
643 	struct acpi_namespace_node *node;
644 
645 	ACPI_FUNCTION_TRACE(acpi_remove_gpe_block);
646 
647 	if (!gpe_device) {
648 		return_ACPI_STATUS(AE_BAD_PARAMETER);
649 	}
650 
651 	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
652 	if (ACPI_FAILURE(status)) {
653 		return (status);
654 	}
655 
656 	node = acpi_ns_validate_handle(gpe_device);
657 	if (!node) {
658 		status = AE_BAD_PARAMETER;
659 		goto unlock_and_exit;
660 	}
661 
662 	/* Get the device_object attached to the node */
663 
664 	obj_desc = acpi_ns_get_attached_object(node);
665 	if (!obj_desc || !obj_desc->device.gpe_block) {
666 		return_ACPI_STATUS(AE_NULL_OBJECT);
667 	}
668 
669 	/* Delete the GPE block (but not the device_object) */
670 
671 	status = acpi_ev_delete_gpe_block(obj_desc->device.gpe_block);
672 	if (ACPI_SUCCESS(status)) {
673 		obj_desc->device.gpe_block = NULL;
674 	}
675 
676       unlock_and_exit:
677 	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
678 	return_ACPI_STATUS(status);
679 }
680 
681 ACPI_EXPORT_SYMBOL(acpi_remove_gpe_block)
682 
683 /*******************************************************************************
684  *
685  * FUNCTION:    acpi_get_gpe_device
686  *
687  * PARAMETERS:  index               - System GPE index (0-current_gpe_count)
688  *              gpe_device          - Where the parent GPE Device is returned
689  *
690  * RETURN:      Status
691  *
692  * DESCRIPTION: Obtain the GPE device associated with the input index. A NULL
693  *              gpe device indicates that the gpe number is contained in one of
694  *              the FADT-defined gpe blocks. Otherwise, the GPE block device.
695  *
696  ******************************************************************************/
697 acpi_status
698 acpi_get_gpe_device(u32 index, acpi_handle *gpe_device)
699 {
700 	struct acpi_gpe_device_info info;
701 	acpi_status status;
702 
703 	ACPI_FUNCTION_TRACE(acpi_get_gpe_device);
704 
705 	if (!gpe_device) {
706 		return_ACPI_STATUS(AE_BAD_PARAMETER);
707 	}
708 
709 	if (index >= acpi_current_gpe_count) {
710 		return_ACPI_STATUS(AE_NOT_EXIST);
711 	}
712 
713 	/* Setup and walk the GPE list */
714 
715 	info.index = index;
716 	info.status = AE_NOT_EXIST;
717 	info.gpe_device = NULL;
718 	info.next_block_base_index = 0;
719 
720 	status = acpi_ev_walk_gpe_list(acpi_ev_get_gpe_device, &info);
721 	if (ACPI_FAILURE(status)) {
722 		return_ACPI_STATUS(status);
723 	}
724 
725 	*gpe_device = ACPI_CAST_PTR(acpi_handle, info.gpe_device);
726 	return_ACPI_STATUS(info.status);
727 }
728 
729 ACPI_EXPORT_SYMBOL(acpi_get_gpe_device)
730 #endif				/* !ACPI_REDUCED_HARDWARE */
731