xref: /netbsd-src/sys/kern/kern_pmf.c (revision 466a16a118933bd295a8a104f095714fadf9cf68)
1 /* $NetBSD: kern_pmf.c,v 1.20 2008/06/17 16:17:21 tsutsui Exp $ */
2 
3 /*-
4  * Copyright (c) 2007 Jared D. McNeill <jmcneill@invisible.ca>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: kern_pmf.c,v 1.20 2008/06/17 16:17:21 tsutsui Exp $");
31 
32 #include <sys/types.h>
33 #include <sys/param.h>
34 #include <sys/malloc.h>
35 #include <sys/buf.h>
36 #include <sys/callout.h>
37 #include <sys/kernel.h>
38 #include <sys/device.h>
39 #include <sys/pmf.h>
40 #include <sys/queue.h>
41 #include <sys/sched.h>
42 #include <sys/syscallargs.h> /* for sys_sync */
43 #include <sys/workqueue.h>
44 #include <prop/proplib.h>
45 #include <sys/condvar.h>
46 #include <sys/mutex.h>
47 #include <sys/proc.h>
48 #include <sys/reboot.h>	/* for RB_NOSYNC */
49 #include <sys/sched.h>
50 
51 /* XXX ugly special case, but for now the only client */
52 #include "wsdisplay.h"
53 #if NWSDISPLAY > 0
54 #include <dev/wscons/wsdisplayvar.h>
55 #endif
56 
57 #ifdef PMF_DEBUG
58 int pmf_debug_event;
59 int pmf_debug_idle;
60 int pmf_debug_transition;
61 
62 #define	PMF_EVENT_PRINTF(x)		if (pmf_debug_event) printf x
63 #define	PMF_IDLE_PRINTF(x)		if (pmf_debug_idle) printf x
64 #define	PMF_TRANSITION_PRINTF(x)	if (pmf_debug_transition) printf x
65 #define	PMF_TRANSITION_PRINTF2(y,x)	if (pmf_debug_transition>y) printf x
66 #else
67 #define	PMF_EVENT_PRINTF(x)		do { } while (0)
68 #define	PMF_IDLE_PRINTF(x)		do { } while (0)
69 #define	PMF_TRANSITION_PRINTF(x)	do { } while (0)
70 #define	PMF_TRANSITION_PRINTF2(y,x)	do { } while (0)
71 #endif
72 
73 /* #define PMF_DEBUG */
74 
75 MALLOC_DEFINE(M_PMF, "pmf", "device pmf messaging memory");
76 
77 static prop_dictionary_t pmf_platform = NULL;
78 static struct workqueue *pmf_event_workqueue;
79 
80 typedef struct pmf_event_handler {
81 	TAILQ_ENTRY(pmf_event_handler) pmf_link;
82 	pmf_generic_event_t pmf_event;
83 	void (*pmf_handler)(device_t);
84 	device_t pmf_device;
85 	bool pmf_global;
86 } pmf_event_handler_t;
87 
88 static TAILQ_HEAD(, pmf_event_handler) pmf_all_events =
89     TAILQ_HEAD_INITIALIZER(pmf_all_events);
90 
91 typedef struct pmf_event_workitem {
92 	struct work		pew_work;
93 	pmf_generic_event_t	pew_event;
94 	device_t		pew_device;
95 } pmf_event_workitem_t;
96 
97 struct shutdown_state {
98 	bool initialized;
99 	deviter_t di;
100 };
101 
102 static device_t shutdown_first(struct shutdown_state *);
103 static device_t shutdown_next(struct shutdown_state *);
104 
105 static bool pmf_device_resume_locked(device_t PMF_FN_PROTO);
106 static bool pmf_device_suspend_locked(device_t PMF_FN_PROTO);
107 
108 static void
109 pmf_event_worker(struct work *wk, void *dummy)
110 {
111 	pmf_event_workitem_t *pew;
112 	pmf_event_handler_t *event;
113 
114 	pew = (void *)wk;
115 	KASSERT(wk == &pew->pew_work);
116 	KASSERT(pew != NULL);
117 
118 	TAILQ_FOREACH(event, &pmf_all_events, pmf_link) {
119 		if (event->pmf_event != pew->pew_event)
120 			continue;
121 		if (event->pmf_device == pew->pew_device || event->pmf_global)
122 			(*event->pmf_handler)(event->pmf_device);
123 	}
124 
125 	free(pew, M_TEMP);
126 }
127 
128 static bool
129 pmf_check_system_drivers(void)
130 {
131 	device_t curdev;
132 	bool unsupported_devs;
133 	deviter_t di;
134 
135 	unsupported_devs = false;
136 	for (curdev = deviter_first(&di, 0); curdev != NULL;
137 	     curdev = deviter_next(&di)) {
138 		if (device_pmf_is_registered(curdev))
139 			continue;
140 		if (!unsupported_devs)
141 			printf("Devices without power management support:");
142 		printf(" %s", device_xname(curdev));
143 		unsupported_devs = true;
144 	}
145 	deviter_release(&di);
146 	if (unsupported_devs) {
147 		printf("\n");
148 		return false;
149 	}
150 	return true;
151 }
152 
153 bool
154 pmf_system_bus_resume(PMF_FN_ARGS1)
155 {
156 	bool rv;
157 	device_t curdev;
158 	deviter_t di;
159 
160 	aprint_debug("Powering devices:");
161 	/* D0 handlers are run in order */
162 	rv = true;
163 	for (curdev = deviter_first(&di, DEVITER_F_ROOT_FIRST); curdev != NULL;
164 	     curdev = deviter_next(&di)) {
165 		if (!device_pmf_is_registered(curdev))
166 			continue;
167 		if (device_is_active(curdev) ||
168 		    !device_is_enabled(curdev))
169 			continue;
170 
171 		aprint_debug(" %s", device_xname(curdev));
172 
173 		if (!device_pmf_bus_resume(curdev PMF_FN_CALL)) {
174 			rv = false;
175 			aprint_debug("(failed)");
176 		}
177 	}
178 	deviter_release(&di);
179 	aprint_debug("\n");
180 
181 	return rv;
182 }
183 
184 bool
185 pmf_system_resume(PMF_FN_ARGS1)
186 {
187 	bool rv;
188 	device_t curdev, parent;
189 	deviter_t di;
190 
191 	if (!pmf_check_system_drivers())
192 		return false;
193 
194 	aprint_debug("Resuming devices:");
195 	/* D0 handlers are run in order */
196 	rv = true;
197 	for (curdev = deviter_first(&di, DEVITER_F_ROOT_FIRST); curdev != NULL;
198 	     curdev = deviter_next(&di)) {
199 		if (device_is_active(curdev) ||
200 		    !device_is_enabled(curdev))
201 			continue;
202 		parent = device_parent(curdev);
203 		if (parent != NULL &&
204 		    !device_is_active(parent))
205 			continue;
206 
207 		aprint_debug(" %s", device_xname(curdev));
208 
209 		if (!pmf_device_resume(curdev PMF_FN_CALL)) {
210 			rv = false;
211 			aprint_debug("(failed)");
212 		}
213 	}
214 	deviter_release(&di);
215 	aprint_debug(".\n");
216 
217 	KERNEL_UNLOCK_ONE(0);
218 #if NWSDISPLAY > 0
219 	if (rv)
220 		wsdisplay_handlex(1);
221 #endif
222 	return rv;
223 }
224 
225 bool
226 pmf_system_suspend(PMF_FN_ARGS1)
227 {
228 	device_t curdev;
229 	deviter_t di;
230 
231 	if (!pmf_check_system_drivers())
232 		return false;
233 #if NWSDISPLAY > 0
234 	if (wsdisplay_handlex(0))
235 		return false;
236 #endif
237 	KERNEL_LOCK(1, 0);
238 
239 	/*
240 	 * Flush buffers only if the shutdown didn't do so
241 	 * already and if there was no panic.
242 	 */
243 	if (doing_shutdown == 0 && panicstr == NULL) {
244 		printf("Flushing disk caches: ");
245 		sys_sync(NULL, NULL, NULL);
246 		if (buf_syncwait() != 0)
247 			printf("giving up\n");
248 		else
249 			printf("done\n");
250 	}
251 
252 	aprint_debug("Suspending devices:");
253 
254 	for (curdev = deviter_first(&di, DEVITER_F_LEAVES_FIRST);
255 	     curdev != NULL;
256 	     curdev = deviter_next(&di)) {
257 		if (!device_is_active(curdev))
258 			continue;
259 
260 		aprint_debug(" %s", device_xname(curdev));
261 
262 		/* XXX joerg check return value and abort suspend */
263 		if (!pmf_device_suspend(curdev PMF_FN_CALL))
264 			aprint_debug("(failed)");
265 	}
266 	deviter_release(&di);
267 
268 	aprint_debug(".\n");
269 
270 	return true;
271 }
272 
273 static device_t
274 shutdown_first(struct shutdown_state *s)
275 {
276 	if (!s->initialized) {
277 		deviter_init(&s->di, DEVITER_F_SHUTDOWN|DEVITER_F_LEAVES_FIRST);
278 		s->initialized = true;
279 	}
280 	return shutdown_next(s);
281 }
282 
283 static device_t
284 shutdown_next(struct shutdown_state *s)
285 {
286 	device_t dv;
287 
288 	while ((dv = deviter_next(&s->di)) != NULL && !device_is_active(dv))
289 		;
290 
291 	return dv;
292 }
293 
294 void
295 pmf_system_shutdown(int how)
296 {
297 	static struct shutdown_state s;
298 	device_t curdev;
299 
300 	aprint_debug("Shutting down devices:");
301 
302 	for (curdev = shutdown_first(&s); curdev != NULL;
303 	     curdev = shutdown_next(&s)) {
304 		aprint_debug(" attempting %s shutdown",
305 		    device_xname(curdev));
306 		if (!device_pmf_is_registered(curdev))
307 			aprint_debug("(skipped)");
308 #if 0 /* needed? */
309 		else if (!device_pmf_class_shutdown(curdev, how))
310 			aprint_debug("(failed)");
311 #endif
312 		else if (!device_pmf_driver_shutdown(curdev, how))
313 			aprint_debug("(failed)");
314 		else if (!device_pmf_bus_shutdown(curdev, how))
315 			aprint_debug("(failed)");
316 	}
317 
318 	aprint_debug(".\n");
319 }
320 
321 bool
322 pmf_set_platform(const char *key, const char *value)
323 {
324 	if (pmf_platform == NULL)
325 		pmf_platform = prop_dictionary_create();
326 	if (pmf_platform == NULL)
327 		return false;
328 
329 	return prop_dictionary_set_cstring(pmf_platform, key, value);
330 }
331 
332 const char *
333 pmf_get_platform(const char *key)
334 {
335 	const char *value;
336 
337 	if (pmf_platform == NULL)
338 		return NULL;
339 
340 	if (!prop_dictionary_get_cstring_nocopy(pmf_platform, key, &value))
341 		return NULL;
342 
343 	return value;
344 }
345 
346 bool
347 pmf_device_register1(device_t dev,
348     bool (*suspend)(device_t PMF_FN_PROTO),
349     bool (*resume)(device_t PMF_FN_PROTO),
350     bool (*shutdown)(device_t, int))
351 {
352 	if (!device_pmf_driver_register(dev, suspend, resume, shutdown))
353 		return false;
354 
355 	if (!device_pmf_driver_child_register(dev)) {
356 		device_pmf_driver_deregister(dev);
357 		return false;
358 	}
359 
360 	return true;
361 }
362 
363 void
364 pmf_device_deregister(device_t dev)
365 {
366 	device_pmf_class_deregister(dev);
367 	device_pmf_bus_deregister(dev);
368 	device_pmf_driver_deregister(dev);
369 }
370 
371 bool
372 pmf_device_suspend_self(device_t dev)
373 {
374 	return pmf_device_suspend(dev, PMF_F_SELF);
375 }
376 
377 bool
378 pmf_device_suspend(device_t dev PMF_FN_ARGS)
379 {
380 	bool rc;
381 
382 	PMF_TRANSITION_PRINTF(("%s: suspend enter\n", device_xname(dev)));
383 	if (!device_pmf_is_registered(dev))
384 		return false;
385 
386 	if (!device_pmf_lock(dev PMF_FN_CALL))
387 		return false;
388 
389 	rc = pmf_device_suspend_locked(dev PMF_FN_CALL);
390 
391 	device_pmf_unlock(dev PMF_FN_CALL);
392 
393 	PMF_TRANSITION_PRINTF(("%s: suspend exit\n", device_xname(dev)));
394 	return rc;
395 }
396 
397 static bool
398 pmf_device_suspend_locked(device_t dev PMF_FN_ARGS)
399 {
400 	PMF_TRANSITION_PRINTF2(1, ("%s: self suspend\n", device_xname(dev)));
401 	device_pmf_self_suspend(dev, flags);
402 	PMF_TRANSITION_PRINTF2(1, ("%s: class suspend\n", device_xname(dev)));
403 	if (!device_pmf_class_suspend(dev PMF_FN_CALL))
404 		return false;
405 	PMF_TRANSITION_PRINTF2(1, ("%s: driver suspend\n", device_xname(dev)));
406 	if (!device_pmf_driver_suspend(dev PMF_FN_CALL))
407 		return false;
408 	PMF_TRANSITION_PRINTF2(1, ("%s: bus suspend\n", device_xname(dev)));
409 	if (!device_pmf_bus_suspend(dev PMF_FN_CALL))
410 		return false;
411 
412 	return true;
413 }
414 
415 bool
416 pmf_device_resume_self(device_t dev)
417 {
418 	return pmf_device_resume(dev, PMF_F_SELF);
419 }
420 
421 bool
422 pmf_device_resume(device_t dev PMF_FN_ARGS)
423 {
424 	bool rc;
425 
426 	PMF_TRANSITION_PRINTF(("%s: resume enter\n", device_xname(dev)));
427 	if (!device_pmf_is_registered(dev))
428 		return false;
429 
430 	if (!device_pmf_lock(dev PMF_FN_CALL))
431 		return false;
432 
433 	rc = pmf_device_resume_locked(dev PMF_FN_CALL);
434 
435 	device_pmf_unlock(dev PMF_FN_CALL);
436 
437 	PMF_TRANSITION_PRINTF(("%s: resume exit\n", device_xname(dev)));
438 	return rc;
439 }
440 
441 static bool
442 pmf_device_resume_locked(device_t dev PMF_FN_ARGS)
443 {
444 	PMF_TRANSITION_PRINTF2(1, ("%s: bus resume\n", device_xname(dev)));
445 	if (!device_pmf_bus_resume(dev PMF_FN_CALL))
446 		return false;
447 	PMF_TRANSITION_PRINTF2(1, ("%s: driver resume\n", device_xname(dev)));
448 	if (!device_pmf_driver_resume(dev PMF_FN_CALL))
449 		return false;
450 	PMF_TRANSITION_PRINTF2(1, ("%s: class resume\n", device_xname(dev)));
451 	if (!device_pmf_class_resume(dev PMF_FN_CALL))
452 		return false;
453 	PMF_TRANSITION_PRINTF2(1, ("%s: self resume\n", device_xname(dev)));
454 	device_pmf_self_resume(dev, flags);
455 
456 	return true;
457 }
458 
459 bool
460 pmf_device_recursive_suspend(device_t dv PMF_FN_ARGS)
461 {
462 	bool rv = true;
463 	device_t curdev;
464 	deviter_t di;
465 
466 	if (!device_is_active(dv))
467 		return true;
468 
469 	for (curdev = deviter_first(&di, 0); curdev != NULL;
470 	     curdev = deviter_next(&di)) {
471 		if (device_parent(curdev) != dv)
472 			continue;
473 		if (!pmf_device_recursive_suspend(curdev PMF_FN_CALL)) {
474 			rv = false;
475 			break;
476 		}
477 	}
478 	deviter_release(&di);
479 
480 	return rv && pmf_device_suspend(dv PMF_FN_CALL);
481 }
482 
483 bool
484 pmf_device_recursive_resume(device_t dv PMF_FN_ARGS)
485 {
486 	device_t parent;
487 
488 	if (device_is_active(dv))
489 		return true;
490 
491 	parent = device_parent(dv);
492 	if (parent != NULL) {
493 		if (!pmf_device_recursive_resume(parent PMF_FN_CALL))
494 			return false;
495 	}
496 
497 	return pmf_device_resume(dv PMF_FN_CALL);
498 }
499 
500 bool
501 pmf_device_resume_subtree(device_t dv PMF_FN_ARGS)
502 {
503 	bool rv = true;
504 	device_t curdev;
505 	deviter_t di;
506 
507 	if (!pmf_device_recursive_resume(dv PMF_FN_CALL))
508 		return false;
509 
510 	for (curdev = deviter_first(&di, 0); curdev != NULL;
511 	     curdev = deviter_next(&di)) {
512 		if (device_parent(curdev) != dv)
513 			continue;
514 		if (!pmf_device_resume_subtree(curdev PMF_FN_CALL)) {
515 			rv = false;
516 			break;
517 		}
518 	}
519 	deviter_release(&di);
520 	return rv;
521 }
522 
523 #include <net/if.h>
524 
525 static bool
526 pmf_class_network_suspend(device_t dev PMF_FN_ARGS)
527 {
528 	struct ifnet *ifp = device_pmf_class_private(dev);
529 	int s;
530 
531 	s = splnet();
532 	(*ifp->if_stop)(ifp, 0);
533 	splx(s);
534 
535 	return true;
536 }
537 
538 static bool
539 pmf_class_network_resume(device_t dev PMF_FN_ARGS)
540 {
541 	struct ifnet *ifp = device_pmf_class_private(dev);
542 	int s;
543 
544 	if ((flags & PMF_F_SELF) != 0)
545 		return true;
546 
547 	s = splnet();
548 	if (ifp->if_flags & IFF_UP) {
549 		ifp->if_flags &= ~IFF_RUNNING;
550 		if ((*ifp->if_init)(ifp) != 0)
551 			aprint_normal_ifnet(ifp, "resume failed\n");
552 		(*ifp->if_start)(ifp);
553 	}
554 	splx(s);
555 
556 	return true;
557 }
558 
559 void
560 pmf_class_network_register(device_t dev, struct ifnet *ifp)
561 {
562 	device_pmf_class_register(dev, ifp, pmf_class_network_suspend,
563 	    pmf_class_network_resume, NULL);
564 }
565 
566 bool
567 pmf_event_inject(device_t dv, pmf_generic_event_t ev)
568 {
569 	pmf_event_workitem_t *pew;
570 
571 	pew = malloc(sizeof(pmf_event_workitem_t), M_TEMP, M_NOWAIT);
572 	if (pew == NULL) {
573 		PMF_EVENT_PRINTF(("%s: PMF event %d dropped (no memory)\n",
574 		    dv ? device_xname(dv) : "<anonymous>", ev));
575 		return false;
576 	}
577 
578 	pew->pew_event = ev;
579 	pew->pew_device = dv;
580 
581 	workqueue_enqueue(pmf_event_workqueue, (void *)pew, NULL);
582 	PMF_EVENT_PRINTF(("%s: PMF event %d injected\n",
583 	    dv ? device_xname(dv) : "<anonymous>", ev));
584 
585 	return true;
586 }
587 
588 bool
589 pmf_event_register(device_t dv, pmf_generic_event_t ev,
590     void (*handler)(device_t), bool global)
591 {
592 	pmf_event_handler_t *event;
593 
594 	event = malloc(sizeof(*event), M_DEVBUF, M_WAITOK);
595 	event->pmf_event = ev;
596 	event->pmf_handler = handler;
597 	event->pmf_device = dv;
598 	event->pmf_global = global;
599 	TAILQ_INSERT_TAIL(&pmf_all_events, event, pmf_link);
600 
601 	return true;
602 }
603 
604 void
605 pmf_event_deregister(device_t dv, pmf_generic_event_t ev,
606     void (*handler)(device_t), bool global)
607 {
608 	pmf_event_handler_t *event;
609 
610 	TAILQ_FOREACH(event, &pmf_all_events, pmf_link) {
611 		if (event->pmf_event != ev)
612 			continue;
613 		if (event->pmf_device != dv)
614 			continue;
615 		if (event->pmf_global != global)
616 			continue;
617 		if (event->pmf_handler != handler)
618 			continue;
619 		TAILQ_REMOVE(&pmf_all_events, event, pmf_link);
620 		free(event, M_DEVBUF);
621 		return;
622 	}
623 }
624 
625 struct display_class_softc {
626 	TAILQ_ENTRY(display_class_softc) dc_link;
627 	device_t dc_dev;
628 };
629 
630 static TAILQ_HEAD(, display_class_softc) all_displays;
631 static callout_t global_idle_counter;
632 static int idle_timeout = 30;
633 
634 static void
635 input_idle(void *dummy)
636 {
637 	PMF_IDLE_PRINTF(("Input idle handler called\n"));
638 	pmf_event_inject(NULL, PMFE_DISPLAY_OFF);
639 }
640 
641 static void
642 input_activity_handler(device_t dv, devactive_t type)
643 {
644 	if (!TAILQ_EMPTY(&all_displays))
645 		callout_schedule(&global_idle_counter, idle_timeout * hz);
646 }
647 
648 static void
649 pmf_class_input_deregister(device_t dv)
650 {
651 	device_active_deregister(dv, input_activity_handler);
652 }
653 
654 bool
655 pmf_class_input_register(device_t dv)
656 {
657 	if (!device_active_register(dv, input_activity_handler))
658 		return false;
659 
660 	device_pmf_class_register(dv, NULL, NULL, NULL,
661 	    pmf_class_input_deregister);
662 
663 	return true;
664 }
665 
666 static void
667 pmf_class_display_deregister(device_t dv)
668 {
669 	struct display_class_softc *sc = device_pmf_class_private(dv);
670 	int s;
671 
672 	s = splsoftclock();
673 	TAILQ_REMOVE(&all_displays, sc, dc_link);
674 	if (TAILQ_EMPTY(&all_displays))
675 		callout_stop(&global_idle_counter);
676 	splx(s);
677 
678 	free(sc, M_DEVBUF);
679 }
680 
681 bool
682 pmf_class_display_register(device_t dv)
683 {
684 	struct display_class_softc *sc;
685 	int s;
686 
687 	sc = malloc(sizeof(*sc), M_DEVBUF, M_WAITOK);
688 
689 	s = splsoftclock();
690 	if (TAILQ_EMPTY(&all_displays))
691 		callout_schedule(&global_idle_counter, idle_timeout * hz);
692 
693 	TAILQ_INSERT_HEAD(&all_displays, sc, dc_link);
694 	splx(s);
695 
696 	device_pmf_class_register(dv, sc, NULL, NULL,
697 	    pmf_class_display_deregister);
698 
699 	return true;
700 }
701 
702 void
703 pmf_init(void)
704 {
705 	int err;
706 
707 	KASSERT(pmf_event_workqueue == NULL);
708 	err = workqueue_create(&pmf_event_workqueue, "pmfevent",
709 	    pmf_event_worker, NULL, PRI_NONE, IPL_VM, 0);
710 	if (err)
711 		panic("couldn't create pmfevent workqueue");
712 
713 	callout_init(&global_idle_counter, 0);
714 	callout_setfunc(&global_idle_counter, input_idle, NULL);
715 }
716