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apm.c revision 1.24.2.1
      1  1.24.2.1      yamt /*	$NetBSD: apm.c,v 1.24.2.1 2012/10/30 17:19:57 yamt Exp $	*/
      2       1.1    itojun /*	$OpenBSD: apm.c,v 1.5 2002/06/07 07:13:59 miod Exp $	*/
      3       1.1    itojun 
      4       1.1    itojun /*-
      5       1.1    itojun  * Copyright (c) 2001 Alexander Guy.  All rights reserved.
      6       1.1    itojun  * Copyright (c) 1998-2001 Michael Shalayeff. All rights reserved.
      7       1.1    itojun  * Copyright (c) 1995 John T. Kohl.  All rights reserved.
      8       1.1    itojun  *
      9       1.1    itojun  * Redistribution and use in source and binary forms, with or without
     10       1.1    itojun  * modification, are permitted provided that the following conditions
     11       1.1    itojun  * are met:
     12       1.1    itojun  * 1. Redistributions of source code must retain the above copyright
     13       1.1    itojun  *    notice, this list of conditions and the following disclaimer.
     14       1.1    itojun  * 2. Redistributions in binary form must reproduce the above copyright
     15       1.1    itojun  *    notice, this list of conditions and the following disclaimer in the
     16       1.1    itojun  *    documentation and/or other materials provided with the distribution.
     17      1.18     david  * 3. Neither the names of the authors nor the names of contributors
     18       1.1    itojun  *    may be used to endorse or promote products derived from this software
     19       1.1    itojun  *    without specific prior written permission.
     20       1.1    itojun  *
     21      1.18     david  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
     22       1.1    itojun  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     23       1.1    itojun  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     24      1.18     david  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
     25       1.1    itojun  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     26       1.1    itojun  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     27       1.1    itojun  * OR SERVICES; LOSS OF MIND, USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     28       1.1    itojun  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     29       1.1    itojun  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     30       1.1    itojun  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     31       1.1    itojun  * SUCH DAMAGE.
     32       1.1    itojun  *
     33       1.1    itojun  */
     34       1.9     lukem 
     35       1.9     lukem #include <sys/cdefs.h>
     36  1.24.2.1      yamt __KERNEL_RCSID(0, "$NetBSD: apm.c,v 1.24.2.1 2012/10/30 17:19:57 yamt Exp $");
     37       1.1    itojun 
     38       1.1    itojun #include "apm.h"
     39       1.1    itojun 
     40       1.1    itojun #if NAPM > 1
     41       1.1    itojun #error only one APM emulation device may be configured
     42       1.1    itojun #endif
     43       1.1    itojun 
     44       1.1    itojun #include <sys/param.h>
     45       1.1    itojun #include <sys/systm.h>
     46       1.1    itojun #include <sys/kernel.h>
     47       1.1    itojun #include <sys/proc.h>
     48       1.1    itojun #include <sys/device.h>
     49       1.1    itojun #include <sys/fcntl.h>
     50       1.1    itojun #include <sys/ioctl.h>
     51      1.17        ad #include <sys/mutex.h>
     52       1.1    itojun #ifdef __OpenBSD__
     53       1.1    itojun #include <sys/event.h>
     54       1.1    itojun #endif
     55       1.1    itojun #ifdef __NetBSD__
     56       1.1    itojun #include <sys/select.h>
     57       1.1    itojun #include <sys/poll.h>
     58       1.1    itojun #include <sys/conf.h>
     59       1.1    itojun #endif
     60       1.1    itojun 
     61       1.1    itojun #ifdef __OpenBSD__
     62       1.1    itojun #include <machine/conf.h>
     63       1.1    itojun #endif
     64       1.1    itojun #include <machine/cpu.h>
     65       1.1    itojun #include <machine/apmvar.h>
     66       1.1    itojun 
     67       1.1    itojun #include <macppc/dev/adbvar.h>
     68       1.1    itojun #include <macppc/dev/pm_direct.h>
     69       1.1    itojun 
     70       1.1    itojun #if defined(APMDEBUG)
     71       1.1    itojun #define DPRINTF(x)	printf x
     72       1.1    itojun #else
     73       1.1    itojun #define	DPRINTF(x)	/**/
     74       1.1    itojun #endif
     75       1.1    itojun 
     76       1.1    itojun #define APM_NEVENTS 16
     77       1.1    itojun 
     78       1.1    itojun struct apm_softc {
     79       1.1    itojun 	struct selinfo sc_rsel;
     80       1.1    itojun #ifdef __OpenBSD__
     81       1.1    itojun 	struct klist sc_note;
     82       1.1    itojun #endif
     83       1.1    itojun 	int    sc_flags;
     84       1.1    itojun 	int	event_count;
     85       1.1    itojun 	int	event_ptr;
     86      1.17        ad 	kmutex_t sc_lock;
     87       1.1    itojun 	struct	apm_event_info event_list[APM_NEVENTS];
     88       1.1    itojun };
     89       1.1    itojun 
     90       1.1    itojun /*
     91       1.1    itojun  * A brief note on the locking protocol: it's very simple; we
     92       1.1    itojun  * assert an exclusive lock any time thread context enters the
     93       1.1    itojun  * APM module.  This is both the APM thread itself, as well as
     94       1.1    itojun  * user context.
     95       1.1    itojun  */
     96       1.1    itojun #ifdef __NetBSD__
     97      1.17        ad #define	APM_LOCK(apmsc)		mutex_enter(&(apmsc)->sc_lock)
     98      1.17        ad #define	APM_UNLOCK(apmsc)	mutex_exit(&(apmsc)->sc_lock)
     99       1.1    itojun #else
    100       1.1    itojun #define APM_LOCK(apmsc)
    101       1.1    itojun #define APM_UNLOCK(apmsc)
    102       1.1    itojun #endif
    103       1.1    itojun 
    104      1.24      matt int apmmatch(device_t, cfdata_t, void *);
    105      1.24      matt void apmattach(device_t, device_t, void *);
    106       1.1    itojun 
    107       1.1    itojun #ifdef __NetBSD__
    108       1.1    itojun #if 0
    109      1.21       dsl static int	apm_record_event(struct apm_softc *, u_int);
    110       1.1    itojun #endif
    111       1.1    itojun #endif
    112       1.1    itojun 
    113  1.24.2.1      yamt CFATTACH_DECL_NEW(apm, sizeof(struct apm_softc),
    114       1.4   thorpej     apmmatch, apmattach, NULL, NULL);
    115       1.1    itojun 
    116       1.1    itojun #ifdef __OpenBSD__
    117       1.1    itojun struct cfdriver apm_cd = {
    118       1.1    itojun 	NULL, "apm", DV_DULL
    119       1.1    itojun };
    120       1.1    itojun #else
    121       1.1    itojun extern struct cfdriver apm_cd;
    122       1.2   gehenna 
    123       1.2   gehenna dev_type_open(apmopen);
    124       1.2   gehenna dev_type_close(apmclose);
    125       1.2   gehenna dev_type_ioctl(apmioctl);
    126       1.2   gehenna dev_type_poll(apmpoll);
    127       1.5  jdolecek dev_type_kqfilter(apmkqfilter);
    128       1.2   gehenna 
    129       1.2   gehenna const struct cdevsw apm_cdevsw = {
    130       1.2   gehenna 	apmopen, apmclose, noread, nowrite, apmioctl,
    131       1.5  jdolecek 	nostop, notty, apmpoll, nommap, apmkqfilter,
    132       1.2   gehenna };
    133       1.1    itojun #endif
    134       1.1    itojun 
    135       1.1    itojun int	apm_evindex;
    136       1.1    itojun 
    137       1.1    itojun #define	APMUNIT(dev)	(minor(dev)&0xf0)
    138       1.1    itojun #define	APMDEV(dev)	(minor(dev)&0x0f)
    139       1.1    itojun #define APMDEV_NORMAL	0
    140       1.1    itojun #define APMDEV_CTL	8
    141       1.1    itojun 
    142       1.1    itojun /*
    143       1.1    itojun  * Flags to control kernel display
    144       1.1    itojun  *	SCFLAG_NOPRINT:		do not output APM power messages due to
    145       1.1    itojun  *				a power change event.
    146       1.1    itojun  *
    147       1.1    itojun  *	SCFLAG_PCTPRINT:	do not output APM power messages due to
    148       1.1    itojun  *				to a power change event unless the battery
    149       1.1    itojun  *				percentage changes.
    150       1.1    itojun  */
    151       1.1    itojun 
    152       1.1    itojun #define SCFLAG_NOPRINT	0x0008000
    153       1.1    itojun #define SCFLAG_PCTPRINT	0x0004000
    154       1.1    itojun #define SCFLAG_PRINT	(SCFLAG_NOPRINT|SCFLAG_PCTPRINT)
    155       1.1    itojun 
    156       1.1    itojun #define	SCFLAG_OREAD 	(1 << 0)
    157       1.1    itojun #define	SCFLAG_OWRITE	(1 << 1)
    158       1.1    itojun #define	SCFLAG_OPEN	(SCFLAG_OREAD|SCFLAG_OWRITE)
    159       1.1    itojun 
    160       1.1    itojun 
    161       1.1    itojun int
    162      1.24      matt apmmatch(device_t parent, cfdata_t match, void *aux)
    163       1.1    itojun {
    164       1.1    itojun 	struct adb_attach_args *aa = (void *)aux;
    165       1.1    itojun 	if (aa->origaddr != ADBADDR_APM ||
    166       1.1    itojun 	    aa->handler_id != ADBADDR_APM ||
    167       1.1    itojun 	    aa->adbaddr != ADBADDR_APM)
    168       1.1    itojun 		return 0;
    169       1.1    itojun 
    170      1.12    briggs 	if (adbHardware != ADB_HW_PMU)
    171       1.1    itojun 		return 0;
    172       1.1    itojun 
    173       1.1    itojun 	return 1;
    174       1.1    itojun }
    175       1.1    itojun 
    176       1.1    itojun void
    177      1.24      matt apmattach(device_t parent, device_t self, void *aux)
    178       1.1    itojun {
    179  1.24.2.1      yamt 	struct apm_softc *sc = device_private(self);
    180       1.1    itojun 	struct pmu_battery_info info;
    181       1.1    itojun 
    182       1.1    itojun 	pm_battery_info(0, &info);
    183       1.1    itojun 
    184       1.1    itojun 	printf(": battery flags 0x%X, ", info.flags);
    185       1.1    itojun 	printf("%d%% charged\n", ((info.cur_charge * 100) / info.max_charge));
    186      1.10   aymeric 
    187      1.10   aymeric 	sc->sc_flags = 0;
    188      1.10   aymeric 	sc->event_ptr = 0;
    189      1.10   aymeric 	sc->event_count = 0;
    190      1.17        ad 	mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_NONE);
    191      1.19     rmind 	selinit(&sc->sc_rsel);
    192       1.1    itojun }
    193       1.1    itojun 
    194       1.1    itojun int
    195      1.20    cegger apmopen(dev_t dev, int flag, int mode, struct lwp *l)
    196       1.1    itojun {
    197       1.1    itojun 	struct apm_softc *sc;
    198       1.1    itojun 	int error = 0;
    199       1.1    itojun 
    200       1.1    itojun 	/* apm0 only */
    201      1.20    cegger 	sc = device_lookup_private(&apm_cd, APMUNIT(dev));
    202      1.20    cegger 	if (sc == NULL)
    203       1.1    itojun 		return ENXIO;
    204       1.1    itojun 
    205       1.1    itojun 	DPRINTF(("apmopen: dev %d pid %d flag %x mode %x\n",
    206      1.15  christos 	    APMDEV(dev), l->l_proc->p_pid, flag, mode));
    207       1.1    itojun 
    208       1.1    itojun 	APM_LOCK(sc);
    209       1.1    itojun 	switch (APMDEV(dev)) {
    210       1.1    itojun 	case APMDEV_CTL:
    211       1.1    itojun 		if (!(flag & FWRITE)) {
    212       1.1    itojun 			error = EINVAL;
    213       1.1    itojun 			break;
    214       1.1    itojun 		}
    215       1.1    itojun 		if (sc->sc_flags & SCFLAG_OWRITE) {
    216       1.1    itojun 			error = EBUSY;
    217       1.1    itojun 			break;
    218       1.1    itojun 		}
    219       1.1    itojun 		sc->sc_flags |= SCFLAG_OWRITE;
    220       1.1    itojun 		break;
    221       1.1    itojun 	case APMDEV_NORMAL:
    222       1.1    itojun 		if (!(flag & FREAD) || (flag & FWRITE)) {
    223       1.1    itojun 			error = EINVAL;
    224       1.1    itojun 			break;
    225       1.1    itojun 		}
    226       1.1    itojun 		sc->sc_flags |= SCFLAG_OREAD;
    227       1.1    itojun 		break;
    228       1.1    itojun 	default:
    229       1.1    itojun 		error = ENXIO;
    230       1.1    itojun 		break;
    231       1.1    itojun 	}
    232       1.1    itojun 	APM_UNLOCK(sc);
    233       1.1    itojun 	return error;
    234       1.1    itojun }
    235       1.1    itojun 
    236       1.1    itojun int
    237      1.20    cegger apmclose(dev_t dev, int flag, int mode, struct lwp *l)
    238       1.1    itojun {
    239       1.1    itojun 	struct apm_softc *sc;
    240       1.1    itojun 
    241       1.1    itojun 	/* apm0 only */
    242      1.20    cegger 	sc = device_lookup_private(&apm_cd, APMUNIT(dev));
    243      1.20    cegger 	if (sc == NULL)
    244       1.1    itojun 		return ENXIO;
    245       1.1    itojun 
    246      1.15  christos 	DPRINTF(("apmclose: pid %d flag %x mode %x\n", l->l_proc->p_pid, flag, mode));
    247       1.1    itojun 
    248       1.1    itojun 	APM_LOCK(sc);
    249       1.1    itojun 	switch (APMDEV(dev)) {
    250       1.1    itojun 	case APMDEV_CTL:
    251       1.1    itojun 		sc->sc_flags &= ~SCFLAG_OWRITE;
    252       1.1    itojun 		break;
    253       1.1    itojun 	case APMDEV_NORMAL:
    254       1.1    itojun 		sc->sc_flags &= ~SCFLAG_OREAD;
    255       1.1    itojun 		break;
    256       1.1    itojun 	}
    257       1.1    itojun 	APM_UNLOCK(sc);
    258       1.1    itojun 	return 0;
    259       1.1    itojun }
    260       1.1    itojun 
    261       1.1    itojun int
    262      1.20    cegger apmioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
    263       1.1    itojun {
    264       1.1    itojun 	struct apm_softc *sc;
    265       1.1    itojun 	struct pmu_battery_info batt;
    266       1.1    itojun 	struct apm_power_info *power;
    267       1.1    itojun 	int error = 0;
    268       1.1    itojun 
    269       1.1    itojun 	/* apm0 only */
    270      1.20    cegger 	sc = device_lookup_private(&apm_cd, APMUNIT(dev));
    271      1.20    cegger 	if (sc == NULL)
    272       1.1    itojun 		return ENXIO;
    273       1.1    itojun 
    274       1.1    itojun 	APM_LOCK(sc);
    275       1.1    itojun 	switch (cmd) {
    276       1.1    itojun 		/* some ioctl names from linux */
    277       1.1    itojun 	case APM_IOC_STANDBY:
    278       1.1    itojun 		if ((flag & FWRITE) == 0)
    279       1.1    itojun 			error = EBADF;
    280       1.1    itojun 	case APM_IOC_SUSPEND:
    281       1.1    itojun 		if ((flag & FWRITE) == 0)
    282       1.1    itojun 			error = EBADF;
    283       1.1    itojun 		break;
    284       1.1    itojun 	case APM_IOC_PRN_CTL:
    285       1.1    itojun 		if ((flag & FWRITE) == 0)
    286       1.1    itojun 			error = EBADF;
    287       1.1    itojun 		else {
    288      1.14   nathanw 			int op = *(int *)data;
    289      1.14   nathanw 			DPRINTF(( "APM_IOC_PRN_CTL: %d\n", op ));
    290      1.14   nathanw 			switch (op) {
    291       1.1    itojun 			case APM_PRINT_ON:	/* enable printing */
    292       1.1    itojun 				sc->sc_flags &= ~SCFLAG_PRINT;
    293       1.1    itojun 				break;
    294       1.1    itojun 			case APM_PRINT_OFF: /* disable printing */
    295       1.1    itojun 				sc->sc_flags &= ~SCFLAG_PRINT;
    296       1.1    itojun 				sc->sc_flags |= SCFLAG_NOPRINT;
    297       1.1    itojun 				break;
    298       1.1    itojun 			case APM_PRINT_PCT: /* disable some printing */
    299       1.1    itojun 				sc->sc_flags &= ~SCFLAG_PRINT;
    300       1.1    itojun 				sc->sc_flags |= SCFLAG_PCTPRINT;
    301       1.1    itojun 				break;
    302       1.1    itojun 			default:
    303       1.1    itojun 				error = EINVAL;
    304       1.1    itojun 				break;
    305       1.1    itojun 			}
    306       1.1    itojun 		}
    307       1.1    itojun 		break;
    308       1.1    itojun 	case APM_IOC_DEV_CTL:
    309       1.1    itojun 		if ((flag & FWRITE) == 0)
    310       1.1    itojun 			error = EBADF;
    311       1.1    itojun 		break;
    312       1.1    itojun 	case APM_IOC_GETPOWER:
    313       1.1    itojun 	        power = (struct apm_power_info *)data;
    314       1.1    itojun 
    315       1.1    itojun 		pm_battery_info(0, &batt);
    316       1.1    itojun 
    317       1.1    itojun 		power->ac_state = ((batt.flags & PMU_PWR_AC_PRESENT) ?
    318       1.1    itojun 		    APM_AC_ON : APM_AC_OFF);
    319       1.1    itojun 		power->battery_life =
    320       1.1    itojun 		    ((batt.cur_charge * 100) / batt.max_charge);
    321       1.1    itojun 
    322       1.1    itojun 		/*
    323       1.1    itojun 		 * If the battery is charging, return the minutes left until
    324       1.1    itojun 		 * charging is complete. apmd knows this.
    325       1.1    itojun 		 */
    326       1.1    itojun 
    327       1.1    itojun 		if (!(batt.flags & PMU_PWR_BATT_PRESENT)) {
    328       1.1    itojun 			power->battery_state = APM_BATT_UNKNOWN;
    329       1.1    itojun 			power->minutes_left = 0;
    330       1.1    itojun 			power->battery_life = 0;
    331       1.1    itojun 		} else if ((power->ac_state == APM_AC_ON) &&
    332       1.1    itojun 			   (batt.draw > 0)) {
    333      1.13    briggs 			power->minutes_left = batt.secs_remaining / 60;
    334       1.1    itojun 			power->battery_state = APM_BATT_CHARGING;
    335       1.1    itojun 		} else {
    336      1.13    briggs 			power->minutes_left = batt.secs_remaining / 60;
    337       1.1    itojun 
    338       1.1    itojun 			/* XXX - Arbitrary */
    339       1.1    itojun 			if (power->battery_life > 60) {
    340       1.1    itojun 				power->battery_state = APM_BATT_HIGH;
    341       1.1    itojun 			} else if (power->battery_life < 10) {
    342       1.1    itojun 				power->battery_state = APM_BATT_CRITICAL;
    343       1.1    itojun 			} else {
    344       1.1    itojun 				power->battery_state = APM_BATT_LOW;
    345       1.1    itojun 			}
    346       1.1    itojun 		}
    347       1.1    itojun 
    348       1.1    itojun 		break;
    349       1.1    itojun 
    350       1.1    itojun 	default:
    351       1.1    itojun 		error = ENOTTY;
    352       1.1    itojun 	}
    353       1.1    itojun 	APM_UNLOCK(sc);
    354       1.1    itojun 
    355       1.1    itojun 	return error;
    356       1.1    itojun }
    357       1.1    itojun 
    358       1.1    itojun #ifdef __NetBSD__
    359       1.1    itojun #if 0
    360       1.1    itojun /*
    361       1.1    itojun  * return 0 if the user will notice and handle the event,
    362       1.1    itojun  * return 1 if the kernel driver should do so.
    363       1.1    itojun  */
    364       1.1    itojun static int
    365      1.20    cegger apm_record_event(struct apm_softc *sc, u_int event_type)
    366       1.1    itojun {
    367       1.1    itojun 	struct apm_event_info *evp;
    368       1.1    itojun 
    369       1.1    itojun 	if ((sc->sc_flags & SCFLAG_OPEN) == 0)
    370       1.1    itojun 		return 1;		/* no user waiting */
    371       1.1    itojun 	if (sc->event_count == APM_NEVENTS) {
    372       1.1    itojun 		DPRINTF(("apm_record_event: queue full!\n"));
    373       1.1    itojun 		return 1;			/* overflow */
    374       1.1    itojun 	}
    375       1.1    itojun 	evp = &sc->event_list[sc->event_ptr];
    376       1.1    itojun 	sc->event_count++;
    377       1.1    itojun 	sc->event_ptr++;
    378       1.1    itojun 	sc->event_ptr %= APM_NEVENTS;
    379       1.1    itojun 	evp->type = event_type;
    380       1.1    itojun 	evp->index = ++apm_evindex;
    381      1.19     rmind 	selnotify(&sc->sc_rsel, 0, 0);
    382       1.1    itojun 	return (sc->sc_flags & SCFLAG_OWRITE) ? 0 : 1; /* user may handle */
    383       1.1    itojun }
    384       1.1    itojun #endif
    385       1.1    itojun 
    386       1.1    itojun int
    387      1.20    cegger apmpoll(dev_t dev, int events, struct lwp *l)
    388       1.1    itojun {
    389      1.20    cegger 	struct apm_softc *sc = device_lookup_private(&apm_cd,APMUNIT(dev));
    390       1.1    itojun 	int revents = 0;
    391       1.1    itojun 
    392       1.1    itojun 	APM_LOCK(sc);
    393       1.1    itojun 	if (events & (POLLIN | POLLRDNORM)) {
    394       1.1    itojun 		if (sc->event_count)
    395       1.1    itojun 			revents |= events & (POLLIN | POLLRDNORM);
    396       1.1    itojun 		else
    397      1.15  christos 			selrecord(l, &sc->sc_rsel);
    398       1.1    itojun 	}
    399       1.1    itojun 	APM_UNLOCK(sc);
    400       1.1    itojun 
    401       1.1    itojun 	return (revents);
    402       1.1    itojun }
    403       1.1    itojun #endif
    404       1.1    itojun 
    405       1.5  jdolecek static void
    406       1.5  jdolecek filt_apmrdetach(struct knote *kn)
    407       1.1    itojun {
    408       1.1    itojun 	struct apm_softc *sc = (struct apm_softc *)kn->kn_hook;
    409       1.1    itojun 
    410       1.5  jdolecek 	APM_LOCK(sc);
    411       1.6  christos 	SLIST_REMOVE(&sc->sc_rsel.sel_klist, kn, knote, kn_selnext);
    412       1.5  jdolecek 	APM_UNLOCK(sc);
    413       1.1    itojun }
    414       1.1    itojun 
    415       1.5  jdolecek static int
    416       1.5  jdolecek filt_apmread(struct knote *kn, long hint)
    417       1.1    itojun {
    418       1.5  jdolecek 	struct apm_softc *sc = kn->kn_hook;
    419       1.1    itojun 
    420       1.5  jdolecek 	kn->kn_data = sc->event_count;
    421       1.5  jdolecek 	return (kn->kn_data > 0);
    422       1.1    itojun }
    423       1.1    itojun 
    424       1.5  jdolecek static struct filterops apmread_filtops =
    425       1.5  jdolecek 	{ 1, NULL, filt_apmrdetach, filt_apmread};
    426       1.5  jdolecek 
    427       1.1    itojun int
    428      1.20    cegger apmkqfilter(dev_t dev, struct knote *kn)
    429       1.1    itojun {
    430      1.20    cegger 	struct apm_softc *sc = device_lookup_private(&apm_cd,APMUNIT(dev));
    431       1.5  jdolecek 	struct klist *klist;
    432       1.1    itojun 
    433       1.1    itojun 	switch (kn->kn_filter) {
    434       1.1    itojun 	case EVFILT_READ:
    435       1.6  christos 		klist = &sc->sc_rsel.sel_klist;
    436       1.1    itojun 		kn->kn_fop = &apmread_filtops;
    437       1.1    itojun 		break;
    438       1.1    itojun 	default:
    439       1.1    itojun 		return (1);
    440       1.1    itojun 	}
    441       1.1    itojun 
    442       1.5  jdolecek 	kn->kn_hook = sc;
    443       1.5  jdolecek 
    444       1.5  jdolecek 	APM_LOCK(sc);
    445       1.5  jdolecek 	SLIST_INSERT_HEAD(klist, kn, kn_selnext);
    446       1.5  jdolecek 	APM_UNLOCK(sc);
    447       1.1    itojun 
    448       1.1    itojun 	return (0);
    449       1.1    itojun }
    450