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ppi.c revision 1.10
      1  1.10  christos /*	$NetBSD: ppi.c,v 1.10 1996/10/13 03:14:20 christos Exp $	*/
      2   1.6       cgd 
      3   1.1       cgd /*
      4   1.5   mycroft  * Copyright (c) 1982, 1990, 1993
      5   1.5   mycroft  *	The Regents of the University of California.  All rights reserved.
      6   1.1       cgd  *
      7   1.1       cgd  * Redistribution and use in source and binary forms, with or without
      8   1.1       cgd  * modification, are permitted provided that the following conditions
      9   1.1       cgd  * are met:
     10   1.1       cgd  * 1. Redistributions of source code must retain the above copyright
     11   1.1       cgd  *    notice, this list of conditions and the following disclaimer.
     12   1.1       cgd  * 2. Redistributions in binary form must reproduce the above copyright
     13   1.1       cgd  *    notice, this list of conditions and the following disclaimer in the
     14   1.1       cgd  *    documentation and/or other materials provided with the distribution.
     15   1.1       cgd  * 3. All advertising materials mentioning features or use of this software
     16   1.1       cgd  *    must display the following acknowledgement:
     17   1.1       cgd  *	This product includes software developed by the University of
     18   1.1       cgd  *	California, Berkeley and its contributors.
     19   1.1       cgd  * 4. Neither the name of the University nor the names of its contributors
     20   1.1       cgd  *    may be used to endorse or promote products derived from this software
     21   1.1       cgd  *    without specific prior written permission.
     22   1.1       cgd  *
     23   1.1       cgd  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     24   1.1       cgd  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     25   1.1       cgd  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     26   1.1       cgd  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     27   1.1       cgd  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     28   1.1       cgd  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     29   1.1       cgd  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     30   1.1       cgd  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     31   1.1       cgd  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     32   1.1       cgd  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     33   1.1       cgd  * SUCH DAMAGE.
     34   1.1       cgd  *
     35   1.6       cgd  *	@(#)ppi.c	8.1 (Berkeley) 6/16/93
     36   1.1       cgd  */
     37   1.1       cgd 
     38   1.1       cgd /*
     39   1.1       cgd  * Printer/Plotter HPIB interface
     40   1.1       cgd  */
     41   1.1       cgd 
     42   1.1       cgd #include "ppi.h"
     43   1.1       cgd #if NPPI > 0
     44   1.1       cgd 
     45   1.3   mycroft #include <sys/param.h>
     46   1.3   mycroft #include <sys/systm.h>
     47   1.3   mycroft #include <sys/errno.h>
     48   1.3   mycroft #include <sys/uio.h>
     49   1.3   mycroft #include <sys/malloc.h>
     50   1.1       cgd 
     51   1.3   mycroft #include <hp300/dev/device.h>
     52   1.3   mycroft #include <hp300/dev/ppiioctl.h>
     53   1.1       cgd 
     54   1.7   thorpej int	ppimatch(), ppistart();
     55   1.7   thorpej void	ppiattach(), ppitimo();
     56   1.1       cgd struct	driver ppidriver = {
     57   1.7   thorpej 	ppimatch, ppiattach, "ppi", ppistart,
     58   1.1       cgd };
     59   1.1       cgd 
     60   1.1       cgd struct	ppi_softc {
     61   1.1       cgd 	int	sc_flags;
     62   1.1       cgd 	struct	devqueue sc_dq;
     63   1.1       cgd 	struct	hp_device *sc_hd;
     64   1.1       cgd 	struct	ppiparam sc_param;
     65   1.1       cgd #define sc_burst sc_param.burst
     66   1.1       cgd #define sc_timo  sc_param.timo
     67   1.1       cgd #define sc_delay sc_param.delay
     68   1.1       cgd 	int	sc_sec;
     69   1.1       cgd } ppi_softc[NPPI];
     70   1.1       cgd 
     71   1.1       cgd /* sc_flags values */
     72   1.1       cgd #define	PPIF_ALIVE	0x01
     73   1.1       cgd #define	PPIF_OPEN	0x02
     74   1.1       cgd #define PPIF_UIO	0x04
     75   1.1       cgd #define PPIF_TIMO	0x08
     76   1.1       cgd #define PPIF_DELAY	0x10
     77   1.1       cgd 
     78   1.1       cgd #define UNIT(x)		minor(x)
     79   1.1       cgd 
     80   1.1       cgd #ifdef DEBUG
     81   1.1       cgd int	ppidebug = 0x80;
     82   1.1       cgd #define PDB_FOLLOW	0x01
     83   1.1       cgd #define PDB_IO		0x02
     84   1.1       cgd #define PDB_NOCHECK	0x80
     85   1.1       cgd #endif
     86   1.1       cgd 
     87   1.7   thorpej int
     88   1.7   thorpej ppimatch(hd)
     89   1.1       cgd 	register struct hp_device *hd;
     90   1.1       cgd {
     91   1.1       cgd 	register struct ppi_softc *sc = &ppi_softc[hd->hp_unit];
     92   1.1       cgd 
     93   1.1       cgd #ifdef DEBUG
     94   1.1       cgd 	if ((ppidebug & PDB_NOCHECK) == 0)
     95   1.1       cgd #endif
     96   1.1       cgd 	/*
     97   1.1       cgd 	 * XXX: the printer/plotter doesn't seem to really return
     98   1.1       cgd 	 * an ID but this will at least prevent us from mistaking
     99   1.1       cgd 	 * a cs80 disk or tape for a ppi device.
    100   1.1       cgd 	 */
    101   1.1       cgd 	if (hpibid(hd->hp_ctlr, hd->hp_slave) & 0x200)
    102   1.7   thorpej 		return (0);
    103   1.7   thorpej 
    104   1.7   thorpej 	sc->sc_hd = hd;
    105   1.7   thorpej 	return (1);
    106   1.7   thorpej }
    107   1.7   thorpej 
    108   1.7   thorpej void
    109   1.7   thorpej ppiattach(hd)
    110   1.7   thorpej 	register struct hp_device *hd;
    111   1.7   thorpej {
    112   1.7   thorpej 	struct ppi_softc *sc = &ppi_softc[hd->hp_unit];
    113   1.7   thorpej 
    114  1.10  christos 	printf("\n");
    115   1.7   thorpej 
    116   1.1       cgd 	sc->sc_flags = PPIF_ALIVE;
    117   1.8   thorpej 	sc->sc_dq.dq_softc = sc;
    118   1.1       cgd 	sc->sc_dq.dq_ctlr = hd->hp_ctlr;
    119   1.1       cgd 	sc->sc_dq.dq_unit = hd->hp_unit;
    120   1.1       cgd 	sc->sc_dq.dq_slave = hd->hp_slave;
    121   1.1       cgd 	sc->sc_dq.dq_driver = &ppidriver;
    122   1.1       cgd }
    123   1.1       cgd 
    124   1.1       cgd ppiopen(dev, flags)
    125   1.1       cgd 	dev_t dev;
    126   1.1       cgd {
    127   1.1       cgd 	register int unit = UNIT(dev);
    128   1.1       cgd 	register struct ppi_softc *sc = &ppi_softc[unit];
    129   1.1       cgd 
    130   1.1       cgd 	if (unit >= NPPI || (sc->sc_flags & PPIF_ALIVE) == 0)
    131   1.1       cgd 		return(ENXIO);
    132   1.1       cgd #ifdef DEBUG
    133   1.1       cgd 	if (ppidebug & PDB_FOLLOW)
    134  1.10  christos 		printf("ppiopen(%x, %x): flags %x\n",
    135   1.1       cgd 		       dev, flags, sc->sc_flags);
    136   1.1       cgd #endif
    137   1.1       cgd 	if (sc->sc_flags & PPIF_OPEN)
    138   1.1       cgd 		return(EBUSY);
    139   1.1       cgd 	sc->sc_flags |= PPIF_OPEN;
    140   1.1       cgd 	sc->sc_burst = PPI_BURST;
    141   1.1       cgd 	sc->sc_timo = ppimstohz(PPI_TIMO);
    142   1.1       cgd 	sc->sc_delay = ppimstohz(PPI_DELAY);
    143   1.1       cgd 	sc->sc_sec = -1;
    144   1.1       cgd 	return(0);
    145   1.1       cgd }
    146   1.1       cgd 
    147   1.1       cgd ppiclose(dev, flags)
    148   1.1       cgd 	dev_t dev;
    149   1.1       cgd {
    150   1.1       cgd 	register int unit = UNIT(dev);
    151   1.1       cgd 	register struct ppi_softc *sc = &ppi_softc[unit];
    152   1.1       cgd 
    153   1.1       cgd #ifdef DEBUG
    154   1.1       cgd 	if (ppidebug & PDB_FOLLOW)
    155  1.10  christos 		printf("ppiclose(%x, %x): flags %x\n",
    156   1.1       cgd 		       dev, flags, sc->sc_flags);
    157   1.1       cgd #endif
    158   1.1       cgd 	sc->sc_flags &= ~PPIF_OPEN;
    159   1.1       cgd 	return(0);
    160   1.1       cgd }
    161   1.1       cgd 
    162   1.5   mycroft ppistart(unit)
    163   1.5   mycroft 	int unit;
    164   1.1       cgd {
    165   1.1       cgd #ifdef DEBUG
    166   1.1       cgd 	if (ppidebug & PDB_FOLLOW)
    167  1.10  christos 		printf("ppistart(%x)\n", unit);
    168   1.1       cgd #endif
    169   1.1       cgd 	ppi_softc[unit].sc_flags &= ~PPIF_DELAY;
    170   1.1       cgd 	wakeup(&ppi_softc[unit]);
    171   1.5   mycroft 	return (0);
    172   1.1       cgd }
    173   1.1       cgd 
    174   1.5   mycroft void
    175   1.5   mycroft ppitimo(unit)
    176   1.5   mycroft 	int unit;
    177   1.1       cgd {
    178   1.1       cgd #ifdef DEBUG
    179   1.1       cgd 	if (ppidebug & PDB_FOLLOW)
    180  1.10  christos 		printf("ppitimo(%x)\n", unit);
    181   1.1       cgd #endif
    182   1.1       cgd 	ppi_softc[unit].sc_flags &= ~(PPIF_UIO|PPIF_TIMO);
    183   1.1       cgd 	wakeup(&ppi_softc[unit]);
    184   1.1       cgd }
    185   1.1       cgd 
    186   1.1       cgd ppiread(dev, uio)
    187   1.1       cgd 	dev_t dev;
    188   1.1       cgd 	struct uio *uio;
    189   1.1       cgd {
    190   1.1       cgd 
    191   1.1       cgd #ifdef DEBUG
    192   1.1       cgd 	if (ppidebug & PDB_FOLLOW)
    193  1.10  christos 		printf("ppiread(%x, %x)\n", dev, uio);
    194   1.1       cgd #endif
    195   1.1       cgd 	return (ppirw(dev, uio));
    196   1.1       cgd }
    197   1.1       cgd 
    198   1.1       cgd ppiwrite(dev, uio)
    199   1.1       cgd 	dev_t dev;
    200   1.1       cgd 	struct uio *uio;
    201   1.1       cgd {
    202   1.1       cgd 
    203   1.1       cgd #ifdef DEBUG
    204   1.1       cgd 	if (ppidebug & PDB_FOLLOW)
    205  1.10  christos 		printf("ppiwrite(%x, %x)\n", dev, uio);
    206   1.1       cgd #endif
    207   1.1       cgd 	return (ppirw(dev, uio));
    208   1.1       cgd }
    209   1.1       cgd 
    210   1.1       cgd ppirw(dev, uio)
    211   1.1       cgd 	dev_t dev;
    212   1.1       cgd 	register struct uio *uio;
    213   1.1       cgd {
    214   1.1       cgd 	int unit = UNIT(dev);
    215   1.1       cgd 	register struct ppi_softc *sc = &ppi_softc[unit];
    216   1.1       cgd 	register int s, len, cnt;
    217   1.1       cgd 	register char *cp;
    218   1.1       cgd 	int error = 0, gotdata = 0;
    219   1.1       cgd 	int buflen;
    220   1.1       cgd 	char *buf;
    221   1.1       cgd 
    222   1.1       cgd 	if (uio->uio_resid == 0)
    223   1.1       cgd 		return(0);
    224   1.1       cgd 
    225   1.1       cgd #ifdef DEBUG
    226   1.1       cgd 	if (ppidebug & (PDB_FOLLOW|PDB_IO))
    227  1.10  christos 		printf("ppirw(%x, %x, %c): burst %d, timo %d, resid %x\n",
    228   1.1       cgd 		       dev, uio, uio->uio_rw == UIO_READ ? 'R' : 'W',
    229   1.1       cgd 		       sc->sc_burst, sc->sc_timo, uio->uio_resid);
    230   1.1       cgd #endif
    231   1.5   mycroft 	buflen = min(sc->sc_burst, uio->uio_resid);
    232   1.1       cgd 	buf = (char *)malloc(buflen, M_DEVBUF, M_WAITOK);
    233   1.1       cgd 	sc->sc_flags |= PPIF_UIO;
    234   1.1       cgd 	if (sc->sc_timo > 0) {
    235   1.1       cgd 		sc->sc_flags |= PPIF_TIMO;
    236   1.4   mycroft 		timeout(ppitimo, (void *)unit, sc->sc_timo);
    237   1.1       cgd 	}
    238   1.1       cgd 	while (uio->uio_resid > 0) {
    239   1.5   mycroft 		len = min(buflen, uio->uio_resid);
    240   1.1       cgd 		cp = buf;
    241   1.1       cgd 		if (uio->uio_rw == UIO_WRITE) {
    242   1.1       cgd 			error = uiomove(cp, len, uio);
    243   1.1       cgd 			if (error)
    244   1.1       cgd 				break;
    245   1.1       cgd 		}
    246   1.1       cgd again:
    247   1.1       cgd 		s = splbio();
    248   1.1       cgd 		if ((sc->sc_flags & PPIF_UIO) && hpibreq(&sc->sc_dq) == 0)
    249   1.1       cgd 			sleep(sc, PRIBIO+1);
    250   1.1       cgd 		/*
    251   1.1       cgd 		 * Check if we timed out during sleep or uiomove
    252   1.1       cgd 		 */
    253   1.1       cgd 		(void) splsoftclock();
    254   1.1       cgd 		if ((sc->sc_flags & PPIF_UIO) == 0) {
    255   1.1       cgd #ifdef DEBUG
    256   1.1       cgd 			if (ppidebug & PDB_IO)
    257  1.10  christos 				printf("ppirw: uiomove/sleep timo, flags %x\n",
    258   1.1       cgd 				       sc->sc_flags);
    259   1.1       cgd #endif
    260   1.1       cgd 			if (sc->sc_flags & PPIF_TIMO) {
    261   1.4   mycroft 				untimeout(ppitimo, (void *)unit);
    262   1.1       cgd 				sc->sc_flags &= ~PPIF_TIMO;
    263   1.1       cgd 			}
    264   1.1       cgd 			splx(s);
    265   1.1       cgd 			break;
    266   1.1       cgd 		}
    267   1.1       cgd 		splx(s);
    268   1.1       cgd 		/*
    269   1.1       cgd 		 * Perform the operation
    270   1.1       cgd 		 */
    271   1.1       cgd 		if (uio->uio_rw == UIO_WRITE)
    272   1.1       cgd 			cnt = hpibsend(sc->sc_hd->hp_ctlr, sc->sc_hd->hp_slave,
    273   1.1       cgd 				       sc->sc_sec, cp, len);
    274   1.1       cgd 		else
    275   1.1       cgd 			cnt = hpibrecv(sc->sc_hd->hp_ctlr, sc->sc_hd->hp_slave,
    276   1.1       cgd 				       sc->sc_sec, cp, len);
    277   1.1       cgd 		s = splbio();
    278   1.1       cgd 		hpibfree(&sc->sc_dq);
    279   1.1       cgd #ifdef DEBUG
    280   1.1       cgd 		if (ppidebug & PDB_IO)
    281  1.10  christos 			printf("ppirw: %s(%d, %d, %x, %x, %d) -> %d\n",
    282   1.1       cgd 			       uio->uio_rw == UIO_READ ? "recv" : "send",
    283   1.1       cgd 			       sc->sc_hd->hp_ctlr, sc->sc_hd->hp_slave,
    284   1.1       cgd 			       sc->sc_sec, cp, len, cnt);
    285   1.1       cgd #endif
    286   1.1       cgd 		splx(s);
    287   1.1       cgd 		if (uio->uio_rw == UIO_READ) {
    288   1.1       cgd 			if (cnt) {
    289   1.1       cgd 				error = uiomove(cp, cnt, uio);
    290   1.1       cgd 				if (error)
    291   1.1       cgd 					break;
    292   1.1       cgd 				gotdata++;
    293   1.1       cgd 			}
    294   1.1       cgd 			/*
    295   1.1       cgd 			 * Didn't get anything this time, but did in the past.
    296   1.1       cgd 			 * Consider us done.
    297   1.1       cgd 			 */
    298   1.1       cgd 			else if (gotdata)
    299   1.1       cgd 				break;
    300   1.1       cgd 		}
    301   1.1       cgd 		s = splsoftclock();
    302   1.1       cgd 		/*
    303   1.1       cgd 		 * Operation timeout (or non-blocking), quit now.
    304   1.1       cgd 		 */
    305   1.1       cgd 		if ((sc->sc_flags & PPIF_UIO) == 0) {
    306   1.1       cgd #ifdef DEBUG
    307   1.1       cgd 			if (ppidebug & PDB_IO)
    308  1.10  christos 				printf("ppirw: timeout/done\n");
    309   1.1       cgd #endif
    310   1.1       cgd 			splx(s);
    311   1.1       cgd 			break;
    312   1.1       cgd 		}
    313   1.1       cgd 		/*
    314   1.1       cgd 		 * Implement inter-read delay
    315   1.1       cgd 		 */
    316   1.1       cgd 		if (sc->sc_delay > 0) {
    317   1.1       cgd 			sc->sc_flags |= PPIF_DELAY;
    318   1.5   mycroft 			timeout((void (*)__P((void *)))ppistart, (void *)unit,
    319   1.5   mycroft 			    sc->sc_delay);
    320   1.1       cgd 			error = tsleep(sc, PCATCH|PZERO+1, "hpib", 0);
    321   1.1       cgd 			if (error) {
    322   1.1       cgd 				splx(s);
    323   1.1       cgd 				break;
    324   1.1       cgd 			}
    325   1.1       cgd 		}
    326   1.1       cgd 		splx(s);
    327   1.1       cgd 		/*
    328   1.1       cgd 		 * Must not call uiomove again til we've used all data
    329   1.1       cgd 		 * that we already grabbed.
    330   1.1       cgd 		 */
    331   1.1       cgd 		if (uio->uio_rw == UIO_WRITE && cnt != len) {
    332   1.1       cgd 			cp += cnt;
    333   1.1       cgd 			len -= cnt;
    334   1.1       cgd 			cnt = 0;
    335   1.1       cgd 			goto again;
    336   1.1       cgd 		}
    337   1.1       cgd 	}
    338   1.1       cgd 	s = splsoftclock();
    339   1.1       cgd 	if (sc->sc_flags & PPIF_TIMO) {
    340   1.4   mycroft 		untimeout(ppitimo, (void *)unit);
    341   1.1       cgd 		sc->sc_flags &= ~PPIF_TIMO;
    342   1.1       cgd 	}
    343   1.1       cgd 	if (sc->sc_flags & PPIF_DELAY) {
    344   1.5   mycroft 		untimeout((void (*)__P((void *)))ppistart, (void *)unit);
    345   1.1       cgd 		sc->sc_flags &= ~PPIF_DELAY;
    346   1.1       cgd 	}
    347   1.1       cgd 	splx(s);
    348   1.1       cgd 	/*
    349   1.1       cgd 	 * Adjust for those chars that we uiomove'ed but never wrote
    350   1.1       cgd 	 */
    351   1.1       cgd 	if (uio->uio_rw == UIO_WRITE && cnt != len) {
    352   1.1       cgd 		uio->uio_resid += (len - cnt);
    353   1.1       cgd #ifdef DEBUG
    354   1.1       cgd 		if (ppidebug & PDB_IO)
    355  1.10  christos 			printf("ppirw: short write, adjust by %d\n",
    356   1.1       cgd 			       len-cnt);
    357   1.1       cgd #endif
    358   1.1       cgd 	}
    359   1.1       cgd 	free(buf, M_DEVBUF);
    360   1.1       cgd #ifdef DEBUG
    361   1.1       cgd 	if (ppidebug & (PDB_FOLLOW|PDB_IO))
    362  1.10  christos 		printf("ppirw: return %d, resid %d\n", error, uio->uio_resid);
    363   1.1       cgd #endif
    364   1.1       cgd 	return (error);
    365   1.1       cgd }
    366   1.1       cgd 
    367   1.3   mycroft ppiioctl(dev, cmd, data, flag, p)
    368   1.1       cgd 	dev_t dev;
    369   1.1       cgd 	int cmd;
    370   1.1       cgd 	caddr_t data;
    371   1.1       cgd 	int flag;
    372   1.3   mycroft 	struct proc *p;
    373   1.1       cgd {
    374   1.1       cgd 	struct ppi_softc *sc = &ppi_softc[UNIT(dev)];
    375   1.1       cgd 	struct ppiparam *pp, *upp;
    376   1.1       cgd 	int error = 0;
    377   1.1       cgd 
    378   1.1       cgd 	switch (cmd) {
    379   1.1       cgd 	case PPIIOCGPARAM:
    380   1.1       cgd 		pp = &sc->sc_param;
    381   1.1       cgd 		upp = (struct ppiparam *)data;
    382   1.1       cgd 		upp->burst = pp->burst;
    383   1.1       cgd 		upp->timo = ppihztoms(pp->timo);
    384   1.1       cgd 		upp->delay = ppihztoms(pp->delay);
    385   1.1       cgd 		break;
    386   1.1       cgd 	case PPIIOCSPARAM:
    387   1.1       cgd 		pp = &sc->sc_param;
    388   1.1       cgd 		upp = (struct ppiparam *)data;
    389   1.1       cgd 		if (upp->burst < PPI_BURST_MIN || upp->burst > PPI_BURST_MAX ||
    390   1.1       cgd 		    upp->delay < PPI_DELAY_MIN || upp->delay > PPI_DELAY_MAX)
    391   1.1       cgd 			return(EINVAL);
    392   1.1       cgd 		pp->burst = upp->burst;
    393   1.1       cgd 		pp->timo = ppimstohz(upp->timo);
    394   1.1       cgd 		pp->delay = ppimstohz(upp->delay);
    395   1.1       cgd 		break;
    396   1.1       cgd 	case PPIIOCSSEC:
    397   1.1       cgd 		sc->sc_sec = *(int *)data;
    398   1.1       cgd 		break;
    399   1.1       cgd 	default:
    400   1.1       cgd 		return(EINVAL);
    401   1.1       cgd 	}
    402   1.1       cgd 	return (error);
    403   1.1       cgd }
    404   1.1       cgd 
    405   1.1       cgd ppihztoms(h)
    406   1.1       cgd 	int h;
    407   1.1       cgd {
    408   1.1       cgd 	extern int hz;
    409   1.1       cgd 	register int m = h;
    410   1.1       cgd 
    411   1.1       cgd 	if (m > 0)
    412   1.1       cgd 		m = m * 1000 / hz;
    413   1.1       cgd 	return(m);
    414   1.1       cgd }
    415   1.1       cgd 
    416   1.1       cgd ppimstohz(m)
    417   1.1       cgd 	int m;
    418   1.1       cgd {
    419   1.1       cgd 	extern int hz;
    420   1.1       cgd 	register int h = m;
    421   1.1       cgd 
    422   1.1       cgd 	if (h > 0) {
    423   1.1       cgd 		h = h * hz / 1000;
    424   1.1       cgd 		if (h == 0)
    425   1.1       cgd 			h = 1000 / hz;
    426   1.1       cgd 	}
    427   1.1       cgd 	return(h);
    428   1.1       cgd }
    429   1.1       cgd #endif
    430