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apm.c revision 1.23.10.1
      1  1.23.10.1    cherry /*	$NetBSD: apm.c,v 1.23.10.1 2011/06/23 14:19:19 cherry 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  1.23.10.1    cherry __KERNEL_RCSID(0, "$NetBSD: apm.c,v 1.23.10.1 2011/06/23 14:19:19 cherry 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 device sc_dev;
     80        1.1    itojun 	struct selinfo sc_rsel;
     81        1.1    itojun #ifdef __OpenBSD__
     82        1.1    itojun 	struct klist sc_note;
     83        1.1    itojun #endif
     84        1.1    itojun 	int    sc_flags;
     85        1.1    itojun 	int	event_count;
     86        1.1    itojun 	int	event_ptr;
     87       1.17        ad 	kmutex_t sc_lock;
     88        1.1    itojun 	struct	apm_event_info event_list[APM_NEVENTS];
     89        1.1    itojun };
     90        1.1    itojun 
     91        1.1    itojun /*
     92        1.1    itojun  * A brief note on the locking protocol: it's very simple; we
     93        1.1    itojun  * assert an exclusive lock any time thread context enters the
     94        1.1    itojun  * APM module.  This is both the APM thread itself, as well as
     95        1.1    itojun  * user context.
     96        1.1    itojun  */
     97        1.1    itojun #ifdef __NetBSD__
     98       1.17        ad #define	APM_LOCK(apmsc)		mutex_enter(&(apmsc)->sc_lock)
     99       1.17        ad #define	APM_UNLOCK(apmsc)	mutex_exit(&(apmsc)->sc_lock)
    100        1.1    itojun #else
    101        1.1    itojun #define APM_LOCK(apmsc)
    102        1.1    itojun #define APM_UNLOCK(apmsc)
    103        1.1    itojun #endif
    104        1.1    itojun 
    105  1.23.10.1    cherry int apmmatch(device_t, cfdata_t, void *);
    106  1.23.10.1    cherry void apmattach(device_t, device_t, void *);
    107        1.1    itojun 
    108        1.1    itojun #ifdef __NetBSD__
    109        1.1    itojun #if 0
    110       1.21       dsl static int	apm_record_event(struct apm_softc *, u_int);
    111        1.1    itojun #endif
    112        1.1    itojun #endif
    113        1.1    itojun 
    114        1.4   thorpej CFATTACH_DECL(apm, sizeof(struct apm_softc),
    115        1.4   thorpej     apmmatch, apmattach, NULL, NULL);
    116        1.1    itojun 
    117        1.1    itojun #ifdef __OpenBSD__
    118        1.1    itojun struct cfdriver apm_cd = {
    119        1.1    itojun 	NULL, "apm", DV_DULL
    120        1.1    itojun };
    121        1.1    itojun #else
    122        1.1    itojun extern struct cfdriver apm_cd;
    123        1.2   gehenna 
    124        1.2   gehenna dev_type_open(apmopen);
    125        1.2   gehenna dev_type_close(apmclose);
    126        1.2   gehenna dev_type_ioctl(apmioctl);
    127        1.2   gehenna dev_type_poll(apmpoll);
    128        1.5  jdolecek dev_type_kqfilter(apmkqfilter);
    129        1.2   gehenna 
    130        1.2   gehenna const struct cdevsw apm_cdevsw = {
    131        1.2   gehenna 	apmopen, apmclose, noread, nowrite, apmioctl,
    132        1.5  jdolecek 	nostop, notty, apmpoll, nommap, apmkqfilter,
    133        1.2   gehenna };
    134        1.1    itojun #endif
    135        1.1    itojun 
    136        1.1    itojun int	apm_evindex;
    137        1.1    itojun 
    138        1.1    itojun #define	APMUNIT(dev)	(minor(dev)&0xf0)
    139        1.1    itojun #define	APMDEV(dev)	(minor(dev)&0x0f)
    140        1.1    itojun #define APMDEV_NORMAL	0
    141        1.1    itojun #define APMDEV_CTL	8
    142        1.1    itojun 
    143        1.1    itojun /*
    144        1.1    itojun  * Flags to control kernel display
    145        1.1    itojun  *	SCFLAG_NOPRINT:		do not output APM power messages due to
    146        1.1    itojun  *				a power change event.
    147        1.1    itojun  *
    148        1.1    itojun  *	SCFLAG_PCTPRINT:	do not output APM power messages due to
    149        1.1    itojun  *				to a power change event unless the battery
    150        1.1    itojun  *				percentage changes.
    151        1.1    itojun  */
    152        1.1    itojun 
    153        1.1    itojun #define SCFLAG_NOPRINT	0x0008000
    154        1.1    itojun #define SCFLAG_PCTPRINT	0x0004000
    155        1.1    itojun #define SCFLAG_PRINT	(SCFLAG_NOPRINT|SCFLAG_PCTPRINT)
    156        1.1    itojun 
    157        1.1    itojun #define	SCFLAG_OREAD 	(1 << 0)
    158        1.1    itojun #define	SCFLAG_OWRITE	(1 << 1)
    159        1.1    itojun #define	SCFLAG_OPEN	(SCFLAG_OREAD|SCFLAG_OWRITE)
    160        1.1    itojun 
    161        1.1    itojun 
    162        1.1    itojun int
    163  1.23.10.1    cherry apmmatch(device_t parent, cfdata_t match, void *aux)
    164        1.1    itojun {
    165        1.1    itojun 	struct adb_attach_args *aa = (void *)aux;
    166        1.1    itojun 	if (aa->origaddr != ADBADDR_APM ||
    167        1.1    itojun 	    aa->handler_id != ADBADDR_APM ||
    168        1.1    itojun 	    aa->adbaddr != ADBADDR_APM)
    169        1.1    itojun 		return 0;
    170        1.1    itojun 
    171       1.12    briggs 	if (adbHardware != ADB_HW_PMU)
    172        1.1    itojun 		return 0;
    173        1.1    itojun 
    174        1.1    itojun 	return 1;
    175        1.1    itojun }
    176        1.1    itojun 
    177        1.1    itojun void
    178  1.23.10.1    cherry apmattach(device_t parent, device_t self, void *aux)
    179        1.1    itojun {
    180       1.10   aymeric 	struct apm_softc *sc = (struct apm_softc *) self;
    181        1.1    itojun 	struct pmu_battery_info info;
    182        1.1    itojun 
    183        1.1    itojun 	pm_battery_info(0, &info);
    184        1.1    itojun 
    185        1.1    itojun 	printf(": battery flags 0x%X, ", info.flags);
    186        1.1    itojun 	printf("%d%% charged\n", ((info.cur_charge * 100) / info.max_charge));
    187       1.10   aymeric 
    188       1.10   aymeric 	sc->sc_flags = 0;
    189       1.10   aymeric 	sc->event_ptr = 0;
    190       1.10   aymeric 	sc->event_count = 0;
    191       1.17        ad 	mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_NONE);
    192       1.19     rmind 	selinit(&sc->sc_rsel);
    193        1.1    itojun }
    194        1.1    itojun 
    195        1.1    itojun int
    196       1.20    cegger apmopen(dev_t dev, int flag, int mode, struct lwp *l)
    197        1.1    itojun {
    198        1.1    itojun 	struct apm_softc *sc;
    199        1.1    itojun 	int error = 0;
    200        1.1    itojun 
    201        1.1    itojun 	/* apm0 only */
    202       1.20    cegger 	sc = device_lookup_private(&apm_cd, APMUNIT(dev));
    203       1.20    cegger 	if (sc == NULL)
    204        1.1    itojun 		return ENXIO;
    205        1.1    itojun 
    206        1.1    itojun 	DPRINTF(("apmopen: dev %d pid %d flag %x mode %x\n",
    207       1.15  christos 	    APMDEV(dev), l->l_proc->p_pid, flag, mode));
    208        1.1    itojun 
    209        1.1    itojun 	APM_LOCK(sc);
    210        1.1    itojun 	switch (APMDEV(dev)) {
    211        1.1    itojun 	case APMDEV_CTL:
    212        1.1    itojun 		if (!(flag & FWRITE)) {
    213        1.1    itojun 			error = EINVAL;
    214        1.1    itojun 			break;
    215        1.1    itojun 		}
    216        1.1    itojun 		if (sc->sc_flags & SCFLAG_OWRITE) {
    217        1.1    itojun 			error = EBUSY;
    218        1.1    itojun 			break;
    219        1.1    itojun 		}
    220        1.1    itojun 		sc->sc_flags |= SCFLAG_OWRITE;
    221        1.1    itojun 		break;
    222        1.1    itojun 	case APMDEV_NORMAL:
    223        1.1    itojun 		if (!(flag & FREAD) || (flag & FWRITE)) {
    224        1.1    itojun 			error = EINVAL;
    225        1.1    itojun 			break;
    226        1.1    itojun 		}
    227        1.1    itojun 		sc->sc_flags |= SCFLAG_OREAD;
    228        1.1    itojun 		break;
    229        1.1    itojun 	default:
    230        1.1    itojun 		error = ENXIO;
    231        1.1    itojun 		break;
    232        1.1    itojun 	}
    233        1.1    itojun 	APM_UNLOCK(sc);
    234        1.1    itojun 	return error;
    235        1.1    itojun }
    236        1.1    itojun 
    237        1.1    itojun int
    238       1.20    cegger apmclose(dev_t dev, int flag, int mode, struct lwp *l)
    239        1.1    itojun {
    240        1.1    itojun 	struct apm_softc *sc;
    241        1.1    itojun 
    242        1.1    itojun 	/* apm0 only */
    243       1.20    cegger 	sc = device_lookup_private(&apm_cd, APMUNIT(dev));
    244       1.20    cegger 	if (sc == NULL)
    245        1.1    itojun 		return ENXIO;
    246        1.1    itojun 
    247       1.15  christos 	DPRINTF(("apmclose: pid %d flag %x mode %x\n", l->l_proc->p_pid, flag, mode));
    248        1.1    itojun 
    249        1.1    itojun 	APM_LOCK(sc);
    250        1.1    itojun 	switch (APMDEV(dev)) {
    251        1.1    itojun 	case APMDEV_CTL:
    252        1.1    itojun 		sc->sc_flags &= ~SCFLAG_OWRITE;
    253        1.1    itojun 		break;
    254        1.1    itojun 	case APMDEV_NORMAL:
    255        1.1    itojun 		sc->sc_flags &= ~SCFLAG_OREAD;
    256        1.1    itojun 		break;
    257        1.1    itojun 	}
    258        1.1    itojun 	APM_UNLOCK(sc);
    259        1.1    itojun 	return 0;
    260        1.1    itojun }
    261        1.1    itojun 
    262        1.1    itojun int
    263       1.20    cegger apmioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
    264        1.1    itojun {
    265        1.1    itojun 	struct apm_softc *sc;
    266        1.1    itojun 	struct pmu_battery_info batt;
    267        1.1    itojun 	struct apm_power_info *power;
    268        1.1    itojun 	int error = 0;
    269        1.1    itojun 
    270        1.1    itojun 	/* apm0 only */
    271       1.20    cegger 	sc = device_lookup_private(&apm_cd, APMUNIT(dev));
    272       1.20    cegger 	if (sc == NULL)
    273        1.1    itojun 		return ENXIO;
    274        1.1    itojun 
    275        1.1    itojun 	APM_LOCK(sc);
    276        1.1    itojun 	switch (cmd) {
    277        1.1    itojun 		/* some ioctl names from linux */
    278        1.1    itojun 	case APM_IOC_STANDBY:
    279        1.1    itojun 		if ((flag & FWRITE) == 0)
    280        1.1    itojun 			error = EBADF;
    281        1.1    itojun 	case APM_IOC_SUSPEND:
    282        1.1    itojun 		if ((flag & FWRITE) == 0)
    283        1.1    itojun 			error = EBADF;
    284        1.1    itojun 		break;
    285        1.1    itojun 	case APM_IOC_PRN_CTL:
    286        1.1    itojun 		if ((flag & FWRITE) == 0)
    287        1.1    itojun 			error = EBADF;
    288        1.1    itojun 		else {
    289       1.14   nathanw 			int op = *(int *)data;
    290       1.14   nathanw 			DPRINTF(( "APM_IOC_PRN_CTL: %d\n", op ));
    291       1.14   nathanw 			switch (op) {
    292        1.1    itojun 			case APM_PRINT_ON:	/* enable printing */
    293        1.1    itojun 				sc->sc_flags &= ~SCFLAG_PRINT;
    294        1.1    itojun 				break;
    295        1.1    itojun 			case APM_PRINT_OFF: /* disable printing */
    296        1.1    itojun 				sc->sc_flags &= ~SCFLAG_PRINT;
    297        1.1    itojun 				sc->sc_flags |= SCFLAG_NOPRINT;
    298        1.1    itojun 				break;
    299        1.1    itojun 			case APM_PRINT_PCT: /* disable some printing */
    300        1.1    itojun 				sc->sc_flags &= ~SCFLAG_PRINT;
    301        1.1    itojun 				sc->sc_flags |= SCFLAG_PCTPRINT;
    302        1.1    itojun 				break;
    303        1.1    itojun 			default:
    304        1.1    itojun 				error = EINVAL;
    305        1.1    itojun 				break;
    306        1.1    itojun 			}
    307        1.1    itojun 		}
    308        1.1    itojun 		break;
    309        1.1    itojun 	case APM_IOC_DEV_CTL:
    310        1.1    itojun 		if ((flag & FWRITE) == 0)
    311        1.1    itojun 			error = EBADF;
    312        1.1    itojun 		break;
    313        1.1    itojun 	case APM_IOC_GETPOWER:
    314        1.1    itojun 	        power = (struct apm_power_info *)data;
    315        1.1    itojun 
    316        1.1    itojun 		pm_battery_info(0, &batt);
    317        1.1    itojun 
    318        1.1    itojun 		power->ac_state = ((batt.flags & PMU_PWR_AC_PRESENT) ?
    319        1.1    itojun 		    APM_AC_ON : APM_AC_OFF);
    320        1.1    itojun 		power->battery_life =
    321        1.1    itojun 		    ((batt.cur_charge * 100) / batt.max_charge);
    322        1.1    itojun 
    323        1.1    itojun 		/*
    324        1.1    itojun 		 * If the battery is charging, return the minutes left until
    325        1.1    itojun 		 * charging is complete. apmd knows this.
    326        1.1    itojun 		 */
    327        1.1    itojun 
    328        1.1    itojun 		if (!(batt.flags & PMU_PWR_BATT_PRESENT)) {
    329        1.1    itojun 			power->battery_state = APM_BATT_UNKNOWN;
    330        1.1    itojun 			power->minutes_left = 0;
    331        1.1    itojun 			power->battery_life = 0;
    332        1.1    itojun 		} else if ((power->ac_state == APM_AC_ON) &&
    333        1.1    itojun 			   (batt.draw > 0)) {
    334       1.13    briggs 			power->minutes_left = batt.secs_remaining / 60;
    335        1.1    itojun 			power->battery_state = APM_BATT_CHARGING;
    336        1.1    itojun 		} else {
    337       1.13    briggs 			power->minutes_left = batt.secs_remaining / 60;
    338        1.1    itojun 
    339        1.1    itojun 			/* XXX - Arbitrary */
    340        1.1    itojun 			if (power->battery_life > 60) {
    341        1.1    itojun 				power->battery_state = APM_BATT_HIGH;
    342        1.1    itojun 			} else if (power->battery_life < 10) {
    343        1.1    itojun 				power->battery_state = APM_BATT_CRITICAL;
    344        1.1    itojun 			} else {
    345        1.1    itojun 				power->battery_state = APM_BATT_LOW;
    346        1.1    itojun 			}
    347        1.1    itojun 		}
    348        1.1    itojun 
    349        1.1    itojun 		break;
    350        1.1    itojun 
    351        1.1    itojun 	default:
    352        1.1    itojun 		error = ENOTTY;
    353        1.1    itojun 	}
    354        1.1    itojun 	APM_UNLOCK(sc);
    355        1.1    itojun 
    356        1.1    itojun 	return error;
    357        1.1    itojun }
    358        1.1    itojun 
    359        1.1    itojun #ifdef __NetBSD__
    360        1.1    itojun #if 0
    361        1.1    itojun /*
    362        1.1    itojun  * return 0 if the user will notice and handle the event,
    363        1.1    itojun  * return 1 if the kernel driver should do so.
    364        1.1    itojun  */
    365        1.1    itojun static int
    366       1.20    cegger apm_record_event(struct apm_softc *sc, u_int event_type)
    367        1.1    itojun {
    368        1.1    itojun 	struct apm_event_info *evp;
    369        1.1    itojun 
    370        1.1    itojun 	if ((sc->sc_flags & SCFLAG_OPEN) == 0)
    371        1.1    itojun 		return 1;		/* no user waiting */
    372        1.1    itojun 	if (sc->event_count == APM_NEVENTS) {
    373        1.1    itojun 		DPRINTF(("apm_record_event: queue full!\n"));
    374        1.1    itojun 		return 1;			/* overflow */
    375        1.1    itojun 	}
    376        1.1    itojun 	evp = &sc->event_list[sc->event_ptr];
    377        1.1    itojun 	sc->event_count++;
    378        1.1    itojun 	sc->event_ptr++;
    379        1.1    itojun 	sc->event_ptr %= APM_NEVENTS;
    380        1.1    itojun 	evp->type = event_type;
    381        1.1    itojun 	evp->index = ++apm_evindex;
    382       1.19     rmind 	selnotify(&sc->sc_rsel, 0, 0);
    383        1.1    itojun 	return (sc->sc_flags & SCFLAG_OWRITE) ? 0 : 1; /* user may handle */
    384        1.1    itojun }
    385        1.1    itojun #endif
    386        1.1    itojun 
    387        1.1    itojun int
    388       1.20    cegger apmpoll(dev_t dev, int events, struct lwp *l)
    389        1.1    itojun {
    390       1.20    cegger 	struct apm_softc *sc = device_lookup_private(&apm_cd,APMUNIT(dev));
    391        1.1    itojun 	int revents = 0;
    392        1.1    itojun 
    393        1.1    itojun 	APM_LOCK(sc);
    394        1.1    itojun 	if (events & (POLLIN | POLLRDNORM)) {
    395        1.1    itojun 		if (sc->event_count)
    396        1.1    itojun 			revents |= events & (POLLIN | POLLRDNORM);
    397        1.1    itojun 		else
    398       1.15  christos 			selrecord(l, &sc->sc_rsel);
    399        1.1    itojun 	}
    400        1.1    itojun 	APM_UNLOCK(sc);
    401        1.1    itojun 
    402        1.1    itojun 	return (revents);
    403        1.1    itojun }
    404        1.1    itojun #endif
    405        1.1    itojun 
    406        1.5  jdolecek static void
    407        1.5  jdolecek filt_apmrdetach(struct knote *kn)
    408        1.1    itojun {
    409        1.1    itojun 	struct apm_softc *sc = (struct apm_softc *)kn->kn_hook;
    410        1.1    itojun 
    411        1.5  jdolecek 	APM_LOCK(sc);
    412        1.6  christos 	SLIST_REMOVE(&sc->sc_rsel.sel_klist, kn, knote, kn_selnext);
    413        1.5  jdolecek 	APM_UNLOCK(sc);
    414        1.1    itojun }
    415        1.1    itojun 
    416        1.5  jdolecek static int
    417        1.5  jdolecek filt_apmread(struct knote *kn, long hint)
    418        1.1    itojun {
    419        1.5  jdolecek 	struct apm_softc *sc = kn->kn_hook;
    420        1.1    itojun 
    421        1.5  jdolecek 	kn->kn_data = sc->event_count;
    422        1.5  jdolecek 	return (kn->kn_data > 0);
    423        1.1    itojun }
    424        1.1    itojun 
    425        1.5  jdolecek static struct filterops apmread_filtops =
    426        1.5  jdolecek 	{ 1, NULL, filt_apmrdetach, filt_apmread};
    427        1.5  jdolecek 
    428        1.1    itojun int
    429       1.20    cegger apmkqfilter(dev_t dev, struct knote *kn)
    430        1.1    itojun {
    431       1.20    cegger 	struct apm_softc *sc = device_lookup_private(&apm_cd,APMUNIT(dev));
    432        1.5  jdolecek 	struct klist *klist;
    433        1.1    itojun 
    434        1.1    itojun 	switch (kn->kn_filter) {
    435        1.1    itojun 	case EVFILT_READ:
    436        1.6  christos 		klist = &sc->sc_rsel.sel_klist;
    437        1.1    itojun 		kn->kn_fop = &apmread_filtops;
    438        1.1    itojun 		break;
    439        1.1    itojun 	default:
    440        1.1    itojun 		return (1);
    441        1.1    itojun 	}
    442        1.1    itojun 
    443        1.5  jdolecek 	kn->kn_hook = sc;
    444        1.5  jdolecek 
    445        1.5  jdolecek 	APM_LOCK(sc);
    446        1.5  jdolecek 	SLIST_INSERT_HEAD(klist, kn, kn_selnext);
    447        1.5  jdolecek 	APM_UNLOCK(sc);
    448        1.1    itojun 
    449        1.1    itojun 	return (0);
    450        1.1    itojun }
    451