xref: /openbmc/linux/drivers/acpi/acpica/evxface.c (revision c67e8ec0)
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3  *
4  * Module Name: evxface - External interfaces for ACPI events
5  *
6  * Copyright (C) 2000 - 2018, Intel Corp.
7  *
8  *****************************************************************************/
9 
10 #define EXPORT_ACPI_INTERFACES
11 
12 #include <acpi/acpi.h>
13 #include "accommon.h"
14 #include "acnamesp.h"
15 #include "acevents.h"
16 #include "acinterp.h"
17 
18 #define _COMPONENT          ACPI_EVENTS
19 ACPI_MODULE_NAME("evxface")
20 #if (!ACPI_REDUCED_HARDWARE)
21 /* Local prototypes */
22 static acpi_status
23 acpi_ev_install_gpe_handler(acpi_handle gpe_device,
24 			    u32 gpe_number,
25 			    u32 type,
26 			    u8 is_raw_handler,
27 			    acpi_gpe_handler address, void *context);
28 
29 #endif
30 
31 
32 /*******************************************************************************
33  *
34  * FUNCTION:    acpi_install_notify_handler
35  *
36  * PARAMETERS:  device          - The device for which notifies will be handled
37  *              handler_type    - The type of handler:
38  *                                  ACPI_SYSTEM_NOTIFY: System Handler (00-7F)
39  *                                  ACPI_DEVICE_NOTIFY: Device Handler (80-FF)
40  *                                  ACPI_ALL_NOTIFY:    Both System and Device
41  *              handler         - Address of the handler
42  *              context         - Value passed to the handler on each GPE
43  *
44  * RETURN:      Status
45  *
46  * DESCRIPTION: Install a handler for notifications on an ACPI Device,
47  *              thermal_zone, or Processor object.
48  *
49  * NOTES:       The Root namespace object may have only one handler for each
50  *              type of notify (System/Device). Device/Thermal/Processor objects
51  *              may have one device notify handler, and multiple system notify
52  *              handlers.
53  *
54  ******************************************************************************/
55 
56 acpi_status
57 acpi_install_notify_handler(acpi_handle device,
58 			    u32 handler_type,
59 			    acpi_notify_handler handler, void *context)
60 {
61 	struct acpi_namespace_node *node =
62 	    ACPI_CAST_PTR(struct acpi_namespace_node, device);
63 	union acpi_operand_object *obj_desc;
64 	union acpi_operand_object *handler_obj;
65 	acpi_status status;
66 	u32 i;
67 
68 	ACPI_FUNCTION_TRACE(acpi_install_notify_handler);
69 
70 	/* Parameter validation */
71 
72 	if ((!device) || (!handler) || (!handler_type) ||
73 	    (handler_type > ACPI_MAX_NOTIFY_HANDLER_TYPE)) {
74 		return_ACPI_STATUS(AE_BAD_PARAMETER);
75 	}
76 
77 	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
78 	if (ACPI_FAILURE(status)) {
79 		return_ACPI_STATUS(status);
80 	}
81 
82 	/*
83 	 * Root Object:
84 	 * Registering a notify handler on the root object indicates that the
85 	 * caller wishes to receive notifications for all objects. Note that
86 	 * only one global handler can be registered per notify type.
87 	 * Ensure that a handler is not already installed.
88 	 */
89 	if (device == ACPI_ROOT_OBJECT) {
90 		for (i = 0; i < ACPI_NUM_NOTIFY_TYPES; i++) {
91 			if (handler_type & (i + 1)) {
92 				if (acpi_gbl_global_notify[i].handler) {
93 					status = AE_ALREADY_EXISTS;
94 					goto unlock_and_exit;
95 				}
96 
97 				acpi_gbl_global_notify[i].handler = handler;
98 				acpi_gbl_global_notify[i].context = context;
99 			}
100 		}
101 
102 		goto unlock_and_exit;	/* Global notify handler installed, all done */
103 	}
104 
105 	/*
106 	 * All Other Objects:
107 	 * Caller will only receive notifications specific to the target
108 	 * object. Note that only certain object types are allowed to
109 	 * receive notifications.
110 	 */
111 
112 	/* Are Notifies allowed on this object? */
113 
114 	if (!acpi_ev_is_notify_object(node)) {
115 		status = AE_TYPE;
116 		goto unlock_and_exit;
117 	}
118 
119 	/* Check for an existing internal object, might not exist */
120 
121 	obj_desc = acpi_ns_get_attached_object(node);
122 	if (!obj_desc) {
123 
124 		/* Create a new object */
125 
126 		obj_desc = acpi_ut_create_internal_object(node->type);
127 		if (!obj_desc) {
128 			status = AE_NO_MEMORY;
129 			goto unlock_and_exit;
130 		}
131 
132 		/* Attach new object to the Node, remove local reference */
133 
134 		status = acpi_ns_attach_object(device, obj_desc, node->type);
135 		acpi_ut_remove_reference(obj_desc);
136 		if (ACPI_FAILURE(status)) {
137 			goto unlock_and_exit;
138 		}
139 	}
140 
141 	/* Ensure that the handler is not already installed in the lists */
142 
143 	for (i = 0; i < ACPI_NUM_NOTIFY_TYPES; i++) {
144 		if (handler_type & (i + 1)) {
145 			handler_obj = obj_desc->common_notify.notify_list[i];
146 			while (handler_obj) {
147 				if (handler_obj->notify.handler == handler) {
148 					status = AE_ALREADY_EXISTS;
149 					goto unlock_and_exit;
150 				}
151 
152 				handler_obj = handler_obj->notify.next[i];
153 			}
154 		}
155 	}
156 
157 	/* Create and populate a new notify handler object */
158 
159 	handler_obj = acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_NOTIFY);
160 	if (!handler_obj) {
161 		status = AE_NO_MEMORY;
162 		goto unlock_and_exit;
163 	}
164 
165 	handler_obj->notify.node = node;
166 	handler_obj->notify.handler_type = handler_type;
167 	handler_obj->notify.handler = handler;
168 	handler_obj->notify.context = context;
169 
170 	/* Install the handler at the list head(s) */
171 
172 	for (i = 0; i < ACPI_NUM_NOTIFY_TYPES; i++) {
173 		if (handler_type & (i + 1)) {
174 			handler_obj->notify.next[i] =
175 			    obj_desc->common_notify.notify_list[i];
176 
177 			obj_desc->common_notify.notify_list[i] = handler_obj;
178 		}
179 	}
180 
181 	/* Add an extra reference if handler was installed in both lists */
182 
183 	if (handler_type == ACPI_ALL_NOTIFY) {
184 		acpi_ut_add_reference(handler_obj);
185 	}
186 
187 unlock_and_exit:
188 	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
189 	return_ACPI_STATUS(status);
190 }
191 
192 ACPI_EXPORT_SYMBOL(acpi_install_notify_handler)
193 
194 /*******************************************************************************
195  *
196  * FUNCTION:    acpi_remove_notify_handler
197  *
198  * PARAMETERS:  device          - The device for which the handler is installed
199  *              handler_type    - The type of handler:
200  *                                  ACPI_SYSTEM_NOTIFY: System Handler (00-7F)
201  *                                  ACPI_DEVICE_NOTIFY: Device Handler (80-FF)
202  *                                  ACPI_ALL_NOTIFY:    Both System and Device
203  *              handler         - Address of the handler
204  *
205  * RETURN:      Status
206  *
207  * DESCRIPTION: Remove a handler for notifies on an ACPI device
208  *
209  ******************************************************************************/
210 acpi_status
211 acpi_remove_notify_handler(acpi_handle device,
212 			   u32 handler_type, acpi_notify_handler handler)
213 {
214 	struct acpi_namespace_node *node =
215 	    ACPI_CAST_PTR(struct acpi_namespace_node, device);
216 	union acpi_operand_object *obj_desc;
217 	union acpi_operand_object *handler_obj;
218 	union acpi_operand_object *previous_handler_obj;
219 	acpi_status status = AE_OK;
220 	u32 i;
221 
222 	ACPI_FUNCTION_TRACE(acpi_remove_notify_handler);
223 
224 	/* Parameter validation */
225 
226 	if ((!device) || (!handler) || (!handler_type) ||
227 	    (handler_type > ACPI_MAX_NOTIFY_HANDLER_TYPE)) {
228 		return_ACPI_STATUS(AE_BAD_PARAMETER);
229 	}
230 
231 	/* Root Object. Global handlers are removed here */
232 
233 	if (device == ACPI_ROOT_OBJECT) {
234 		for (i = 0; i < ACPI_NUM_NOTIFY_TYPES; i++) {
235 			if (handler_type & (i + 1)) {
236 				status =
237 				    acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
238 				if (ACPI_FAILURE(status)) {
239 					return_ACPI_STATUS(status);
240 				}
241 
242 				if (!acpi_gbl_global_notify[i].handler ||
243 				    (acpi_gbl_global_notify[i].handler !=
244 				     handler)) {
245 					status = AE_NOT_EXIST;
246 					goto unlock_and_exit;
247 				}
248 
249 				ACPI_DEBUG_PRINT((ACPI_DB_INFO,
250 						  "Removing global notify handler\n"));
251 
252 				acpi_gbl_global_notify[i].handler = NULL;
253 				acpi_gbl_global_notify[i].context = NULL;
254 
255 				(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
256 
257 				/* Make sure all deferred notify tasks are completed */
258 
259 				acpi_os_wait_events_complete();
260 			}
261 		}
262 
263 		return_ACPI_STATUS(AE_OK);
264 	}
265 
266 	/* All other objects: Are Notifies allowed on this object? */
267 
268 	if (!acpi_ev_is_notify_object(node)) {
269 		return_ACPI_STATUS(AE_TYPE);
270 	}
271 
272 	/* Must have an existing internal object */
273 
274 	obj_desc = acpi_ns_get_attached_object(node);
275 	if (!obj_desc) {
276 		return_ACPI_STATUS(AE_NOT_EXIST);
277 	}
278 
279 	/* Internal object exists. Find the handler and remove it */
280 
281 	for (i = 0; i < ACPI_NUM_NOTIFY_TYPES; i++) {
282 		if (handler_type & (i + 1)) {
283 			status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
284 			if (ACPI_FAILURE(status)) {
285 				return_ACPI_STATUS(status);
286 			}
287 
288 			handler_obj = obj_desc->common_notify.notify_list[i];
289 			previous_handler_obj = NULL;
290 
291 			/* Attempt to find the handler in the handler list */
292 
293 			while (handler_obj &&
294 			       (handler_obj->notify.handler != handler)) {
295 				previous_handler_obj = handler_obj;
296 				handler_obj = handler_obj->notify.next[i];
297 			}
298 
299 			if (!handler_obj) {
300 				status = AE_NOT_EXIST;
301 				goto unlock_and_exit;
302 			}
303 
304 			/* Remove the handler object from the list */
305 
306 			if (previous_handler_obj) {	/* Handler is not at the list head */
307 				previous_handler_obj->notify.next[i] =
308 				    handler_obj->notify.next[i];
309 			} else {	/* Handler is at the list head */
310 
311 				obj_desc->common_notify.notify_list[i] =
312 				    handler_obj->notify.next[i];
313 			}
314 
315 			(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
316 
317 			/* Make sure all deferred notify tasks are completed */
318 
319 			acpi_os_wait_events_complete();
320 			acpi_ut_remove_reference(handler_obj);
321 		}
322 	}
323 
324 	return_ACPI_STATUS(status);
325 
326 unlock_and_exit:
327 	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
328 	return_ACPI_STATUS(status);
329 }
330 
331 ACPI_EXPORT_SYMBOL(acpi_remove_notify_handler)
332 
333 /*******************************************************************************
334  *
335  * FUNCTION:    acpi_install_exception_handler
336  *
337  * PARAMETERS:  handler         - Pointer to the handler function for the
338  *                                event
339  *
340  * RETURN:      Status
341  *
342  * DESCRIPTION: Saves the pointer to the handler function
343  *
344  ******************************************************************************/
345 #ifdef ACPI_FUTURE_USAGE
346 acpi_status acpi_install_exception_handler(acpi_exception_handler handler)
347 {
348 	acpi_status status;
349 
350 	ACPI_FUNCTION_TRACE(acpi_install_exception_handler);
351 
352 	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
353 	if (ACPI_FAILURE(status)) {
354 		return_ACPI_STATUS(status);
355 	}
356 
357 	/* Don't allow two handlers. */
358 
359 	if (acpi_gbl_exception_handler) {
360 		status = AE_ALREADY_EXISTS;
361 		goto cleanup;
362 	}
363 
364 	/* Install the handler */
365 
366 	acpi_gbl_exception_handler = handler;
367 
368 cleanup:
369 	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
370 	return_ACPI_STATUS(status);
371 }
372 
373 ACPI_EXPORT_SYMBOL(acpi_install_exception_handler)
374 #endif
375 
376 #if (!ACPI_REDUCED_HARDWARE)
377 /*******************************************************************************
378  *
379  * FUNCTION:    acpi_install_sci_handler
380  *
381  * PARAMETERS:  address             - Address of the handler
382  *              context             - Value passed to the handler on each SCI
383  *
384  * RETURN:      Status
385  *
386  * DESCRIPTION: Install a handler for a System Control Interrupt.
387  *
388  ******************************************************************************/
389 acpi_status acpi_install_sci_handler(acpi_sci_handler address, void *context)
390 {
391 	struct acpi_sci_handler_info *new_sci_handler;
392 	struct acpi_sci_handler_info *sci_handler;
393 	acpi_cpu_flags flags;
394 	acpi_status status;
395 
396 	ACPI_FUNCTION_TRACE(acpi_install_sci_handler);
397 
398 	if (!address) {
399 		return_ACPI_STATUS(AE_BAD_PARAMETER);
400 	}
401 
402 	/* Allocate and init a handler object */
403 
404 	new_sci_handler = ACPI_ALLOCATE(sizeof(struct acpi_sci_handler_info));
405 	if (!new_sci_handler) {
406 		return_ACPI_STATUS(AE_NO_MEMORY);
407 	}
408 
409 	new_sci_handler->address = address;
410 	new_sci_handler->context = context;
411 
412 	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
413 	if (ACPI_FAILURE(status)) {
414 		goto exit;
415 	}
416 
417 	/* Lock list during installation */
418 
419 	flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
420 	sci_handler = acpi_gbl_sci_handler_list;
421 
422 	/* Ensure handler does not already exist */
423 
424 	while (sci_handler) {
425 		if (address == sci_handler->address) {
426 			status = AE_ALREADY_EXISTS;
427 			goto unlock_and_exit;
428 		}
429 
430 		sci_handler = sci_handler->next;
431 	}
432 
433 	/* Install the new handler into the global list (at head) */
434 
435 	new_sci_handler->next = acpi_gbl_sci_handler_list;
436 	acpi_gbl_sci_handler_list = new_sci_handler;
437 
438 unlock_and_exit:
439 
440 	acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
441 	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
442 
443 exit:
444 	if (ACPI_FAILURE(status)) {
445 		ACPI_FREE(new_sci_handler);
446 	}
447 	return_ACPI_STATUS(status);
448 }
449 
450 ACPI_EXPORT_SYMBOL(acpi_install_sci_handler)
451 
452 /*******************************************************************************
453  *
454  * FUNCTION:    acpi_remove_sci_handler
455  *
456  * PARAMETERS:  address             - Address of the handler
457  *
458  * RETURN:      Status
459  *
460  * DESCRIPTION: Remove a handler for a System Control Interrupt.
461  *
462  ******************************************************************************/
463 acpi_status acpi_remove_sci_handler(acpi_sci_handler address)
464 {
465 	struct acpi_sci_handler_info *prev_sci_handler;
466 	struct acpi_sci_handler_info *next_sci_handler;
467 	acpi_cpu_flags flags;
468 	acpi_status status;
469 
470 	ACPI_FUNCTION_TRACE(acpi_remove_sci_handler);
471 
472 	if (!address) {
473 		return_ACPI_STATUS(AE_BAD_PARAMETER);
474 	}
475 
476 	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
477 	if (ACPI_FAILURE(status)) {
478 		return_ACPI_STATUS(status);
479 	}
480 
481 	/* Remove the SCI handler with lock */
482 
483 	flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
484 
485 	prev_sci_handler = NULL;
486 	next_sci_handler = acpi_gbl_sci_handler_list;
487 	while (next_sci_handler) {
488 		if (next_sci_handler->address == address) {
489 
490 			/* Unlink and free the SCI handler info block */
491 
492 			if (prev_sci_handler) {
493 				prev_sci_handler->next = next_sci_handler->next;
494 			} else {
495 				acpi_gbl_sci_handler_list =
496 				    next_sci_handler->next;
497 			}
498 
499 			acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
500 			ACPI_FREE(next_sci_handler);
501 			goto unlock_and_exit;
502 		}
503 
504 		prev_sci_handler = next_sci_handler;
505 		next_sci_handler = next_sci_handler->next;
506 	}
507 
508 	acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
509 	status = AE_NOT_EXIST;
510 
511 unlock_and_exit:
512 	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
513 	return_ACPI_STATUS(status);
514 }
515 
516 ACPI_EXPORT_SYMBOL(acpi_remove_sci_handler)
517 
518 /*******************************************************************************
519  *
520  * FUNCTION:    acpi_install_global_event_handler
521  *
522  * PARAMETERS:  handler         - Pointer to the global event handler function
523  *              context         - Value passed to the handler on each event
524  *
525  * RETURN:      Status
526  *
527  * DESCRIPTION: Saves the pointer to the handler function. The global handler
528  *              is invoked upon each incoming GPE and Fixed Event. It is
529  *              invoked at interrupt level at the time of the event dispatch.
530  *              Can be used to update event counters, etc.
531  *
532  ******************************************************************************/
533 acpi_status
534 acpi_install_global_event_handler(acpi_gbl_event_handler handler, void *context)
535 {
536 	acpi_status status;
537 
538 	ACPI_FUNCTION_TRACE(acpi_install_global_event_handler);
539 
540 	/* Parameter validation */
541 
542 	if (!handler) {
543 		return_ACPI_STATUS(AE_BAD_PARAMETER);
544 	}
545 
546 	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
547 	if (ACPI_FAILURE(status)) {
548 		return_ACPI_STATUS(status);
549 	}
550 
551 	/* Don't allow two handlers. */
552 
553 	if (acpi_gbl_global_event_handler) {
554 		status = AE_ALREADY_EXISTS;
555 		goto cleanup;
556 	}
557 
558 	acpi_gbl_global_event_handler = handler;
559 	acpi_gbl_global_event_handler_context = context;
560 
561 cleanup:
562 	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
563 	return_ACPI_STATUS(status);
564 }
565 
566 ACPI_EXPORT_SYMBOL(acpi_install_global_event_handler)
567 
568 /*******************************************************************************
569  *
570  * FUNCTION:    acpi_install_fixed_event_handler
571  *
572  * PARAMETERS:  event           - Event type to enable.
573  *              handler         - Pointer to the handler function for the
574  *                                event
575  *              context         - Value passed to the handler on each GPE
576  *
577  * RETURN:      Status
578  *
579  * DESCRIPTION: Saves the pointer to the handler function and then enables the
580  *              event.
581  *
582  ******************************************************************************/
583 acpi_status
584 acpi_install_fixed_event_handler(u32 event,
585 				 acpi_event_handler handler, void *context)
586 {
587 	acpi_status status;
588 
589 	ACPI_FUNCTION_TRACE(acpi_install_fixed_event_handler);
590 
591 	/* Parameter validation */
592 
593 	if (event > ACPI_EVENT_MAX) {
594 		return_ACPI_STATUS(AE_BAD_PARAMETER);
595 	}
596 
597 	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
598 	if (ACPI_FAILURE(status)) {
599 		return_ACPI_STATUS(status);
600 	}
601 
602 	/* Do not allow multiple handlers */
603 
604 	if (acpi_gbl_fixed_event_handlers[event].handler) {
605 		status = AE_ALREADY_EXISTS;
606 		goto cleanup;
607 	}
608 
609 	/* Install the handler before enabling the event */
610 
611 	acpi_gbl_fixed_event_handlers[event].handler = handler;
612 	acpi_gbl_fixed_event_handlers[event].context = context;
613 
614 	status = acpi_clear_event(event);
615 	if (ACPI_SUCCESS(status))
616 		status = acpi_enable_event(event, 0);
617 	if (ACPI_FAILURE(status)) {
618 		ACPI_WARNING((AE_INFO,
619 			      "Could not enable fixed event - %s (%u)",
620 			      acpi_ut_get_event_name(event), event));
621 
622 		/* Remove the handler */
623 
624 		acpi_gbl_fixed_event_handlers[event].handler = NULL;
625 		acpi_gbl_fixed_event_handlers[event].context = NULL;
626 	} else {
627 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
628 				  "Enabled fixed event %s (%X), Handler=%p\n",
629 				  acpi_ut_get_event_name(event), event,
630 				  handler));
631 	}
632 
633 cleanup:
634 	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
635 	return_ACPI_STATUS(status);
636 }
637 
638 ACPI_EXPORT_SYMBOL(acpi_install_fixed_event_handler)
639 
640 /*******************************************************************************
641  *
642  * FUNCTION:    acpi_remove_fixed_event_handler
643  *
644  * PARAMETERS:  event           - Event type to disable.
645  *              handler         - Address of the handler
646  *
647  * RETURN:      Status
648  *
649  * DESCRIPTION: Disables the event and unregisters the event handler.
650  *
651  ******************************************************************************/
652 acpi_status
653 acpi_remove_fixed_event_handler(u32 event, acpi_event_handler handler)
654 {
655 	acpi_status status = AE_OK;
656 
657 	ACPI_FUNCTION_TRACE(acpi_remove_fixed_event_handler);
658 
659 	/* Parameter validation */
660 
661 	if (event > ACPI_EVENT_MAX) {
662 		return_ACPI_STATUS(AE_BAD_PARAMETER);
663 	}
664 
665 	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
666 	if (ACPI_FAILURE(status)) {
667 		return_ACPI_STATUS(status);
668 	}
669 
670 	/* Disable the event before removing the handler */
671 
672 	status = acpi_disable_event(event, 0);
673 
674 	/* Always Remove the handler */
675 
676 	acpi_gbl_fixed_event_handlers[event].handler = NULL;
677 	acpi_gbl_fixed_event_handlers[event].context = NULL;
678 
679 	if (ACPI_FAILURE(status)) {
680 		ACPI_WARNING((AE_INFO,
681 			      "Could not disable fixed event - %s (%u)",
682 			      acpi_ut_get_event_name(event), event));
683 	} else {
684 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
685 				  "Disabled fixed event - %s (%X)\n",
686 				  acpi_ut_get_event_name(event), event));
687 	}
688 
689 	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
690 	return_ACPI_STATUS(status);
691 }
692 
693 ACPI_EXPORT_SYMBOL(acpi_remove_fixed_event_handler)
694 
695 /*******************************************************************************
696  *
697  * FUNCTION:    acpi_ev_install_gpe_handler
698  *
699  * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
700  *                                defined GPEs)
701  *              gpe_number      - The GPE number within the GPE block
702  *              type            - Whether this GPE should be treated as an
703  *                                edge- or level-triggered interrupt.
704  *              is_raw_handler  - Whether this GPE should be handled using
705  *                                the special GPE handler mode.
706  *              address         - Address of the handler
707  *              context         - Value passed to the handler on each GPE
708  *
709  * RETURN:      Status
710  *
711  * DESCRIPTION: Internal function to install a handler for a General Purpose
712  *              Event.
713  *
714  ******************************************************************************/
715 static acpi_status
716 acpi_ev_install_gpe_handler(acpi_handle gpe_device,
717 			    u32 gpe_number,
718 			    u32 type,
719 			    u8 is_raw_handler,
720 			    acpi_gpe_handler address, void *context)
721 {
722 	struct acpi_gpe_event_info *gpe_event_info;
723 	struct acpi_gpe_handler_info *handler;
724 	acpi_status status;
725 	acpi_cpu_flags flags;
726 
727 	ACPI_FUNCTION_TRACE(ev_install_gpe_handler);
728 
729 	/* Parameter validation */
730 
731 	if ((!address) || (type & ~ACPI_GPE_XRUPT_TYPE_MASK)) {
732 		return_ACPI_STATUS(AE_BAD_PARAMETER);
733 	}
734 
735 	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
736 	if (ACPI_FAILURE(status)) {
737 		return_ACPI_STATUS(status);
738 	}
739 
740 	/* Allocate and init handler object (before lock) */
741 
742 	handler = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_gpe_handler_info));
743 	if (!handler) {
744 		status = AE_NO_MEMORY;
745 		goto unlock_and_exit;
746 	}
747 
748 	flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
749 
750 	/* Ensure that we have a valid GPE number */
751 
752 	gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
753 	if (!gpe_event_info) {
754 		status = AE_BAD_PARAMETER;
755 		goto free_and_exit;
756 	}
757 
758 	/* Make sure that there isn't a handler there already */
759 
760 	if ((ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags) ==
761 	     ACPI_GPE_DISPATCH_HANDLER) ||
762 	    (ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags) ==
763 	     ACPI_GPE_DISPATCH_RAW_HANDLER)) {
764 		status = AE_ALREADY_EXISTS;
765 		goto free_and_exit;
766 	}
767 
768 	handler->address = address;
769 	handler->context = context;
770 	handler->method_node = gpe_event_info->dispatch.method_node;
771 	handler->original_flags = (u8)(gpe_event_info->flags &
772 				       (ACPI_GPE_XRUPT_TYPE_MASK |
773 					ACPI_GPE_DISPATCH_MASK));
774 
775 	/*
776 	 * If the GPE is associated with a method, it may have been enabled
777 	 * automatically during initialization, in which case it has to be
778 	 * disabled now to avoid spurious execution of the handler.
779 	 */
780 	if (((ACPI_GPE_DISPATCH_TYPE(handler->original_flags) ==
781 	      ACPI_GPE_DISPATCH_METHOD) ||
782 	     (ACPI_GPE_DISPATCH_TYPE(handler->original_flags) ==
783 	      ACPI_GPE_DISPATCH_NOTIFY)) && gpe_event_info->runtime_count) {
784 		handler->originally_enabled = TRUE;
785 		(void)acpi_ev_remove_gpe_reference(gpe_event_info);
786 
787 		/* Sanity check of original type against new type */
788 
789 		if (type !=
790 		    (u32)(gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK)) {
791 			ACPI_WARNING((AE_INFO,
792 				      "GPE type mismatch (level/edge)"));
793 		}
794 	}
795 
796 	/* Install the handler */
797 
798 	gpe_event_info->dispatch.handler = handler;
799 
800 	/* Setup up dispatch flags to indicate handler (vs. method/notify) */
801 
802 	gpe_event_info->flags &=
803 	    ~(ACPI_GPE_XRUPT_TYPE_MASK | ACPI_GPE_DISPATCH_MASK);
804 	gpe_event_info->flags |=
805 	    (u8)(type |
806 		 (is_raw_handler ? ACPI_GPE_DISPATCH_RAW_HANDLER :
807 		  ACPI_GPE_DISPATCH_HANDLER));
808 
809 	acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
810 
811 unlock_and_exit:
812 	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
813 	return_ACPI_STATUS(status);
814 
815 free_and_exit:
816 	acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
817 	ACPI_FREE(handler);
818 	goto unlock_and_exit;
819 }
820 
821 /*******************************************************************************
822  *
823  * FUNCTION:    acpi_install_gpe_handler
824  *
825  * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
826  *                                defined GPEs)
827  *              gpe_number      - The GPE number within the GPE block
828  *              type            - Whether this GPE should be treated as an
829  *                                edge- or level-triggered interrupt.
830  *              address         - Address of the handler
831  *              context         - Value passed to the handler on each GPE
832  *
833  * RETURN:      Status
834  *
835  * DESCRIPTION: Install a handler for a General Purpose Event.
836  *
837  ******************************************************************************/
838 
839 acpi_status
840 acpi_install_gpe_handler(acpi_handle gpe_device,
841 			 u32 gpe_number,
842 			 u32 type, acpi_gpe_handler address, void *context)
843 {
844 	acpi_status status;
845 
846 	ACPI_FUNCTION_TRACE(acpi_install_gpe_handler);
847 
848 	status = acpi_ev_install_gpe_handler(gpe_device, gpe_number, type,
849 					     FALSE, address, context);
850 
851 	return_ACPI_STATUS(status);
852 }
853 
854 ACPI_EXPORT_SYMBOL(acpi_install_gpe_handler)
855 
856 /*******************************************************************************
857  *
858  * FUNCTION:    acpi_install_gpe_raw_handler
859  *
860  * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
861  *                                defined GPEs)
862  *              gpe_number      - The GPE number within the GPE block
863  *              type            - Whether this GPE should be treated as an
864  *                                edge- or level-triggered interrupt.
865  *              address         - Address of the handler
866  *              context         - Value passed to the handler on each GPE
867  *
868  * RETURN:      Status
869  *
870  * DESCRIPTION: Install a handler for a General Purpose Event.
871  *
872  ******************************************************************************/
873 acpi_status
874 acpi_install_gpe_raw_handler(acpi_handle gpe_device,
875 			     u32 gpe_number,
876 			     u32 type, acpi_gpe_handler address, void *context)
877 {
878 	acpi_status status;
879 
880 	ACPI_FUNCTION_TRACE(acpi_install_gpe_raw_handler);
881 
882 	status = acpi_ev_install_gpe_handler(gpe_device, gpe_number, type,
883 					     TRUE, address, context);
884 
885 	return_ACPI_STATUS(status);
886 }
887 
888 ACPI_EXPORT_SYMBOL(acpi_install_gpe_raw_handler)
889 
890 /*******************************************************************************
891  *
892  * FUNCTION:    acpi_remove_gpe_handler
893  *
894  * PARAMETERS:  gpe_device      - Namespace node for the GPE (NULL for FADT
895  *                                defined GPEs)
896  *              gpe_number      - The event to remove a handler
897  *              address         - Address of the handler
898  *
899  * RETURN:      Status
900  *
901  * DESCRIPTION: Remove a handler for a General Purpose acpi_event.
902  *
903  ******************************************************************************/
904 acpi_status
905 acpi_remove_gpe_handler(acpi_handle gpe_device,
906 			u32 gpe_number, acpi_gpe_handler address)
907 {
908 	struct acpi_gpe_event_info *gpe_event_info;
909 	struct acpi_gpe_handler_info *handler;
910 	acpi_status status;
911 	acpi_cpu_flags flags;
912 
913 	ACPI_FUNCTION_TRACE(acpi_remove_gpe_handler);
914 
915 	/* Parameter validation */
916 
917 	if (!address) {
918 		return_ACPI_STATUS(AE_BAD_PARAMETER);
919 	}
920 
921 	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
922 	if (ACPI_FAILURE(status)) {
923 		return_ACPI_STATUS(status);
924 	}
925 
926 	flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
927 
928 	/* Ensure that we have a valid GPE number */
929 
930 	gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);
931 	if (!gpe_event_info) {
932 		status = AE_BAD_PARAMETER;
933 		goto unlock_and_exit;
934 	}
935 
936 	/* Make sure that a handler is indeed installed */
937 
938 	if ((ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags) !=
939 	     ACPI_GPE_DISPATCH_HANDLER) &&
940 	    (ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags) !=
941 	     ACPI_GPE_DISPATCH_RAW_HANDLER)) {
942 		status = AE_NOT_EXIST;
943 		goto unlock_and_exit;
944 	}
945 
946 	/* Make sure that the installed handler is the same */
947 
948 	if (gpe_event_info->dispatch.handler->address != address) {
949 		status = AE_BAD_PARAMETER;
950 		goto unlock_and_exit;
951 	}
952 
953 	/* Remove the handler */
954 
955 	handler = gpe_event_info->dispatch.handler;
956 	gpe_event_info->dispatch.handler = NULL;
957 
958 	/* Restore Method node (if any), set dispatch flags */
959 
960 	gpe_event_info->dispatch.method_node = handler->method_node;
961 	gpe_event_info->flags &=
962 	    ~(ACPI_GPE_XRUPT_TYPE_MASK | ACPI_GPE_DISPATCH_MASK);
963 	gpe_event_info->flags |= handler->original_flags;
964 
965 	/*
966 	 * If the GPE was previously associated with a method and it was
967 	 * enabled, it should be enabled at this point to restore the
968 	 * post-initialization configuration.
969 	 */
970 	if (((ACPI_GPE_DISPATCH_TYPE(handler->original_flags) ==
971 	      ACPI_GPE_DISPATCH_METHOD) ||
972 	     (ACPI_GPE_DISPATCH_TYPE(handler->original_flags) ==
973 	      ACPI_GPE_DISPATCH_NOTIFY)) && handler->originally_enabled) {
974 		(void)acpi_ev_add_gpe_reference(gpe_event_info);
975 		if (ACPI_GPE_IS_POLLING_NEEDED(gpe_event_info)) {
976 
977 			/* Poll edge triggered GPEs to handle existing events */
978 
979 			acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
980 			(void)acpi_ev_detect_gpe(gpe_device, gpe_event_info,
981 						 gpe_number);
982 			flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
983 		}
984 	}
985 
986 	acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
987 	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
988 
989 	/* Make sure all deferred GPE tasks are completed */
990 
991 	acpi_os_wait_events_complete();
992 
993 	/* Now we can free the handler object */
994 
995 	ACPI_FREE(handler);
996 	return_ACPI_STATUS(status);
997 
998 unlock_and_exit:
999 	acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
1000 
1001 	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
1002 	return_ACPI_STATUS(status);
1003 }
1004 
1005 ACPI_EXPORT_SYMBOL(acpi_remove_gpe_handler)
1006 
1007 /*******************************************************************************
1008  *
1009  * FUNCTION:    acpi_acquire_global_lock
1010  *
1011  * PARAMETERS:  timeout         - How long the caller is willing to wait
1012  *              handle          - Where the handle to the lock is returned
1013  *                                (if acquired)
1014  *
1015  * RETURN:      Status
1016  *
1017  * DESCRIPTION: Acquire the ACPI Global Lock
1018  *
1019  * Note: Allows callers with the same thread ID to acquire the global lock
1020  * multiple times. In other words, externally, the behavior of the global lock
1021  * is identical to an AML mutex. On the first acquire, a new handle is
1022  * returned. On any subsequent calls to acquire by the same thread, the same
1023  * handle is returned.
1024  *
1025  ******************************************************************************/
1026 acpi_status acpi_acquire_global_lock(u16 timeout, u32 *handle)
1027 {
1028 	acpi_status status;
1029 
1030 	if (!handle) {
1031 		return (AE_BAD_PARAMETER);
1032 	}
1033 
1034 	/* Must lock interpreter to prevent race conditions */
1035 
1036 	acpi_ex_enter_interpreter();
1037 
1038 	status = acpi_ex_acquire_mutex_object(timeout,
1039 					      acpi_gbl_global_lock_mutex,
1040 					      acpi_os_get_thread_id());
1041 
1042 	if (ACPI_SUCCESS(status)) {
1043 
1044 		/* Return the global lock handle (updated in acpi_ev_acquire_global_lock) */
1045 
1046 		*handle = acpi_gbl_global_lock_handle;
1047 	}
1048 
1049 	acpi_ex_exit_interpreter();
1050 	return (status);
1051 }
1052 
1053 ACPI_EXPORT_SYMBOL(acpi_acquire_global_lock)
1054 
1055 /*******************************************************************************
1056  *
1057  * FUNCTION:    acpi_release_global_lock
1058  *
1059  * PARAMETERS:  handle      - Returned from acpi_acquire_global_lock
1060  *
1061  * RETURN:      Status
1062  *
1063  * DESCRIPTION: Release the ACPI Global Lock. The handle must be valid.
1064  *
1065  ******************************************************************************/
1066 acpi_status acpi_release_global_lock(u32 handle)
1067 {
1068 	acpi_status status;
1069 
1070 	if (!handle || (handle != acpi_gbl_global_lock_handle)) {
1071 		return (AE_NOT_ACQUIRED);
1072 	}
1073 
1074 	status = acpi_ex_release_mutex_object(acpi_gbl_global_lock_mutex);
1075 	return (status);
1076 }
1077 
1078 ACPI_EXPORT_SYMBOL(acpi_release_global_lock)
1079 #endif				/* !ACPI_REDUCED_HARDWARE */
1080