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lpt.c revision 1.48
      1  1.48   thorpej /*	$NetBSD: lpt.c,v 1.48 1998/01/12 09:23:29 thorpej Exp $	*/
      2  1.23       cgd 
      3   1.1       cgd /*
      4  1.11   mycroft  * Copyright (c) 1993, 1994 Charles Hannum.
      5   1.1       cgd  * Copyright (c) 1990 William F. Jolitz, TeleMuse
      6   1.1       cgd  * All rights reserved.
      7   1.1       cgd  *
      8   1.1       cgd  * Redistribution and use in source and binary forms, with or without
      9   1.1       cgd  * modification, are permitted provided that the following conditions
     10   1.1       cgd  * are met:
     11   1.1       cgd  * 1. Redistributions of source code must retain the above copyright
     12   1.1       cgd  *    notice, this list of conditions and the following disclaimer.
     13   1.1       cgd  * 2. Redistributions in binary form must reproduce the above copyright
     14   1.1       cgd  *    notice, this list of conditions and the following disclaimer in the
     15   1.1       cgd  *    documentation and/or other materials provided with the distribution.
     16   1.1       cgd  * 3. All advertising materials mentioning features or use of this software
     17   1.1       cgd  *    must display the following acknowledgement:
     18   1.1       cgd  *	This software is a component of "386BSD" developed by
     19   1.1       cgd  *	William F. Jolitz, TeleMuse.
     20   1.1       cgd  * 4. Neither the name of the developer nor the name "386BSD"
     21   1.1       cgd  *    may be used to endorse or promote products derived from this software
     22   1.1       cgd  *    without specific prior written permission.
     23   1.1       cgd  *
     24   1.1       cgd  * THIS SOFTWARE IS A COMPONENT OF 386BSD DEVELOPED BY WILLIAM F. JOLITZ
     25   1.1       cgd  * AND IS INTENDED FOR RESEARCH AND EDUCATIONAL PURPOSES ONLY. THIS
     26   1.1       cgd  * SOFTWARE SHOULD NOT BE CONSIDERED TO BE A COMMERCIAL PRODUCT.
     27   1.1       cgd  * THE DEVELOPER URGES THAT USERS WHO REQUIRE A COMMERCIAL PRODUCT
     28   1.1       cgd  * NOT MAKE USE OF THIS WORK.
     29   1.1       cgd  *
     30   1.1       cgd  * FOR USERS WHO WISH TO UNDERSTAND THE 386BSD SYSTEM DEVELOPED
     31   1.1       cgd  * BY WILLIAM F. JOLITZ, WE RECOMMEND THE USER STUDY WRITTEN
     32   1.1       cgd  * REFERENCES SUCH AS THE  "PORTING UNIX TO THE 386" SERIES
     33   1.1       cgd  * (BEGINNING JANUARY 1991 "DR. DOBBS JOURNAL", USA AND BEGINNING
     34   1.1       cgd  * JUNE 1991 "UNIX MAGAZIN", GERMANY) BY WILLIAM F. JOLITZ AND
     35   1.1       cgd  * LYNNE GREER JOLITZ, AS WELL AS OTHER BOOKS ON UNIX AND THE
     36   1.1       cgd  * ON-LINE 386BSD USER MANUAL BEFORE USE. A BOOK DISCUSSING THE INTERNALS
     37   1.1       cgd  * OF 386BSD ENTITLED "386BSD FROM THE INSIDE OUT" WILL BE AVAILABLE LATE 1992.
     38   1.1       cgd  *
     39   1.1       cgd  * THIS SOFTWARE IS PROVIDED BY THE DEVELOPER ``AS IS'' AND
     40   1.1       cgd  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     41   1.1       cgd  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     42   1.1       cgd  * ARE DISCLAIMED.  IN NO EVENT SHALL THE DEVELOPER BE LIABLE
     43   1.1       cgd  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     44   1.1       cgd  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     45   1.1       cgd  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     46   1.1       cgd  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     47   1.1       cgd  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     48   1.1       cgd  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     49   1.1       cgd  * SUCH DAMAGE.
     50   1.1       cgd  */
     51   1.1       cgd 
     52   1.1       cgd /*
     53  1.45        is  * Device Driver for AT style parallel printer port
     54   1.1       cgd  */
     55   1.1       cgd 
     56   1.9   mycroft #include <sys/param.h>
     57   1.9   mycroft #include <sys/systm.h>
     58   1.9   mycroft #include <sys/proc.h>
     59   1.9   mycroft #include <sys/user.h>
     60  1.47   thorpej #include <sys/malloc.h>
     61   1.9   mycroft #include <sys/kernel.h>
     62   1.9   mycroft #include <sys/ioctl.h>
     63   1.9   mycroft #include <sys/uio.h>
     64  1.11   mycroft #include <sys/device.h>
     65  1.38  christos #include <sys/conf.h>
     66  1.11   mycroft #include <sys/syslog.h>
     67   1.1       cgd 
     68  1.39   mycroft #include <machine/bus.h>
     69  1.37       cgd #include <machine/intr.h>
     70   1.9   mycroft 
     71  1.45        is #include <dev/ic/lptreg.h>
     72  1.45        is #include <dev/ic/lptvar.h>
     73   1.1       cgd 
     74  1.11   mycroft #define	TIMEOUT		hz*16	/* wait up to 16 seconds for a ready */
     75  1.11   mycroft #define	STEP		hz/4
     76  1.11   mycroft 
     77  1.11   mycroft #define	LPTPRI		(PZERO+8)
     78  1.11   mycroft #define	LPT_BSIZE	1024
     79   1.1       cgd 
     80  1.45        is #define LPTDEBUG
     81  1.45        is 
     82  1.44     mikel #ifndef LPTDEBUG
     83  1.38  christos #define LPRINTF(a)
     84   1.1       cgd #else
     85  1.44     mikel #define LPRINTF(a)	if (lptdebug) printf a
     86  1.44     mikel int lptdebug = 0;
     87   1.1       cgd #endif
     88   1.1       cgd 
     89  1.38  christos /* XXX does not belong here */
     90  1.38  christos cdev_decl(lpt);
     91  1.38  christos 
     92  1.48   thorpej extern struct cfdriver lpt_cd;
     93   1.1       cgd 
     94  1.11   mycroft #define	LPTUNIT(s)	(minor(s) & 0x1f)
     95  1.11   mycroft #define	LPTFLAGS(s)	(minor(s) & 0xe0)
     96   1.1       cgd 
     97  1.15   mycroft void
     98  1.45        is lpt_attach_subr(sc)
     99  1.45        is 	struct lpt_softc *sc;
    100   1.1       cgd {
    101  1.42   thorpej 	bus_space_tag_t iot;
    102  1.42   thorpej 	bus_space_handle_t ioh;
    103  1.15   mycroft 
    104   1.6   mycroft 	sc->sc_state = 0;
    105  1.32       cgd 
    106  1.45        is 	iot = sc->sc_iot;
    107  1.45        is 	ioh = sc->sc_ioh;
    108  1.32       cgd 
    109  1.42   thorpej 	bus_space_write_1(iot, ioh, lpt_control, LPC_NINIT);
    110   1.1       cgd }
    111   1.1       cgd 
    112   1.1       cgd /*
    113  1.11   mycroft  * Reset the printer, then wait until it's selected and not busy.
    114   1.1       cgd  */
    115  1.11   mycroft int
    116  1.38  christos lptopen(dev, flag, mode, p)
    117   1.1       cgd 	dev_t dev;
    118   1.1       cgd 	int flag;
    119  1.38  christos 	int mode;
    120  1.38  christos 	struct proc *p;
    121   1.1       cgd {
    122  1.11   mycroft 	int unit = LPTUNIT(dev);
    123  1.11   mycroft 	u_char flags = LPTFLAGS(dev);
    124  1.11   mycroft 	struct lpt_softc *sc;
    125  1.42   thorpej 	bus_space_tag_t iot;
    126  1.42   thorpej 	bus_space_handle_t ioh;
    127  1.11   mycroft 	u_char control;
    128  1.11   mycroft 	int error;
    129  1.11   mycroft 	int spin;
    130  1.11   mycroft 
    131  1.33   thorpej 	if (unit >= lpt_cd.cd_ndevs)
    132  1.11   mycroft 		return ENXIO;
    133  1.33   thorpej 	sc = lpt_cd.cd_devs[unit];
    134  1.15   mycroft 	if (!sc)
    135  1.11   mycroft 		return ENXIO;
    136  1.11   mycroft 
    137  1.45        is #if 0	/* XXX what to do? */
    138  1.25   mycroft 	if (sc->sc_irq == IRQUNK && (flags & LPT_NOINTR) == 0)
    139  1.11   mycroft 		return ENXIO;
    140  1.45        is #endif
    141  1.11   mycroft 
    142  1.11   mycroft #ifdef DIAGNOSTIC
    143  1.11   mycroft 	if (sc->sc_state)
    144  1.41  christos 		printf("%s: stat=0x%x not zero\n", sc->sc_dev.dv_xname,
    145  1.11   mycroft 		    sc->sc_state);
    146  1.11   mycroft #endif
    147  1.11   mycroft 
    148  1.11   mycroft 	if (sc->sc_state)
    149  1.11   mycroft 		return EBUSY;
    150   1.1       cgd 
    151  1.11   mycroft 	sc->sc_state = LPT_INIT;
    152  1.11   mycroft 	sc->sc_flags = flags;
    153  1.44     mikel 	LPRINTF(("%s: open: flags=0x%x\n", sc->sc_dev.dv_xname,
    154  1.44     mikel 	    (unsigned)flags));
    155  1.42   thorpej 	iot = sc->sc_iot;
    156  1.32       cgd 	ioh = sc->sc_ioh;
    157  1.11   mycroft 
    158  1.11   mycroft 	if ((flags & LPT_NOPRIME) == 0) {
    159  1.11   mycroft 		/* assert INIT for 100 usec to start up printer */
    160  1.42   thorpej 		bus_space_write_1(iot, ioh, lpt_control, LPC_SELECT);
    161  1.14   mycroft 		delay(100);
    162   1.1       cgd 	}
    163  1.11   mycroft 
    164  1.11   mycroft 	control = LPC_SELECT | LPC_NINIT;
    165  1.42   thorpej 	bus_space_write_1(iot, ioh, lpt_control, control);
    166   1.1       cgd 
    167   1.1       cgd 	/* wait till ready (printer running diagnostics) */
    168  1.25   mycroft 	for (spin = 0; NOT_READY_ERR(); spin += STEP) {
    169  1.11   mycroft 		if (spin >= TIMEOUT) {
    170   1.1       cgd 			sc->sc_state = 0;
    171  1.11   mycroft 			return EBUSY;
    172   1.1       cgd 		}
    173   1.1       cgd 
    174   1.1       cgd 		/* wait 1/4 second, give up if we get a signal */
    175  1.38  christos 		error = tsleep((caddr_t)sc, LPTPRI | PCATCH, "lptopen", STEP);
    176  1.38  christos 		if (error != EWOULDBLOCK) {
    177   1.1       cgd 			sc->sc_state = 0;
    178  1.11   mycroft 			return error;
    179   1.1       cgd 		}
    180   1.1       cgd 	}
    181   1.1       cgd 
    182  1.11   mycroft 	if ((flags & LPT_NOINTR) == 0)
    183  1.11   mycroft 		control |= LPC_IENABLE;
    184  1.11   mycroft 	if (flags & LPT_AUTOLF)
    185  1.11   mycroft 		control |= LPC_AUTOLF;
    186  1.11   mycroft 	sc->sc_control = control;
    187  1.42   thorpej 	bus_space_write_1(iot, ioh, lpt_control, control);
    188  1.11   mycroft 
    189  1.47   thorpej 	sc->sc_inbuf = malloc(LPT_BSIZE, M_DEVBUF, M_WAITOK);
    190  1.11   mycroft 	sc->sc_count = 0;
    191  1.11   mycroft 	sc->sc_state = LPT_OPEN;
    192  1.25   mycroft 
    193  1.25   mycroft 	if ((sc->sc_flags & LPT_NOINTR) == 0)
    194  1.25   mycroft 		lptwakeup(sc);
    195  1.11   mycroft 
    196  1.38  christos 	LPRINTF(("%s: opened\n", sc->sc_dev.dv_xname));
    197  1.11   mycroft 	return 0;
    198   1.1       cgd }
    199   1.1       cgd 
    200  1.11   mycroft int
    201  1.46        is lptnotready(status, sc)
    202  1.11   mycroft 	u_char status;
    203   1.1       cgd 	struct lpt_softc *sc;
    204  1.11   mycroft {
    205  1.21   mycroft 	u_char new;
    206  1.21   mycroft 
    207  1.25   mycroft 	status = (status ^ LPS_INVERT) & LPS_MASK;
    208  1.21   mycroft 	new = status & ~sc->sc_laststatus;
    209  1.21   mycroft 	sc->sc_laststatus = status;
    210   1.1       cgd 
    211  1.27   mycroft 	if (new & LPS_SELECT)
    212  1.27   mycroft 		log(LOG_NOTICE, "%s: offline\n", sc->sc_dev.dv_xname);
    213  1.27   mycroft 	else if (new & LPS_NOPAPER)
    214  1.11   mycroft 		log(LOG_NOTICE, "%s: out of paper\n", sc->sc_dev.dv_xname);
    215  1.21   mycroft 	else if (new & LPS_NERR)
    216  1.11   mycroft 		log(LOG_NOTICE, "%s: output error\n", sc->sc_dev.dv_xname);
    217   1.1       cgd 
    218  1.25   mycroft 	return status;
    219  1.11   mycroft }
    220  1.11   mycroft 
    221  1.11   mycroft void
    222  1.25   mycroft lptwakeup(arg)
    223  1.18       cgd 	void *arg;
    224  1.18       cgd {
    225  1.25   mycroft 	struct lpt_softc *sc = arg;
    226  1.11   mycroft 	int s;
    227  1.11   mycroft 
    228  1.13   mycroft 	s = spltty();
    229  1.16   mycroft 	lptintr(sc);
    230  1.13   mycroft 	splx(s);
    231  1.11   mycroft 
    232  1.25   mycroft 	timeout(lptwakeup, sc, STEP);
    233   1.1       cgd }
    234   1.1       cgd 
    235   1.1       cgd /*
    236  1.11   mycroft  * Close the device, and free the local line buffer.
    237   1.1       cgd  */
    238  1.36   mycroft int
    239  1.38  christos lptclose(dev, flag, mode, p)
    240  1.11   mycroft 	dev_t dev;
    241   1.1       cgd 	int flag;
    242  1.38  christos 	int mode;
    243  1.38  christos 	struct proc *p;
    244   1.1       cgd {
    245  1.11   mycroft 	int unit = LPTUNIT(dev);
    246  1.33   thorpej 	struct lpt_softc *sc = lpt_cd.cd_devs[unit];
    247  1.42   thorpej 	bus_space_tag_t iot = sc->sc_iot;
    248  1.42   thorpej 	bus_space_handle_t ioh = sc->sc_ioh;
    249   1.1       cgd 
    250  1.11   mycroft 	if (sc->sc_count)
    251  1.46        is 		(void) lptpushbytes(sc);
    252   1.1       cgd 
    253  1.25   mycroft 	if ((sc->sc_flags & LPT_NOINTR) == 0)
    254  1.25   mycroft 		untimeout(lptwakeup, sc);
    255  1.25   mycroft 
    256  1.42   thorpej 	bus_space_write_1(iot, ioh, lpt_control, LPC_NINIT);
    257   1.1       cgd 	sc->sc_state = 0;
    258  1.42   thorpej 	bus_space_write_1(iot, ioh, lpt_control, LPC_NINIT);
    259  1.47   thorpej 	free(sc->sc_inbuf, M_DEVBUF);
    260  1.11   mycroft 
    261  1.38  christos 	LPRINTF(("%s: closed\n", sc->sc_dev.dv_xname));
    262  1.11   mycroft 	return 0;
    263  1.11   mycroft }
    264  1.11   mycroft 
    265  1.11   mycroft int
    266  1.46        is lptpushbytes(sc)
    267  1.11   mycroft 	struct lpt_softc *sc;
    268  1.11   mycroft {
    269  1.42   thorpej 	bus_space_tag_t iot = sc->sc_iot;
    270  1.42   thorpej 	bus_space_handle_t ioh = sc->sc_ioh;
    271  1.11   mycroft 	int error;
    272  1.11   mycroft 
    273  1.11   mycroft 	if (sc->sc_flags & LPT_NOINTR) {
    274  1.11   mycroft 		int spin, tic;
    275  1.11   mycroft 		u_char control = sc->sc_control;
    276  1.11   mycroft 
    277  1.11   mycroft 		while (sc->sc_count > 0) {
    278  1.11   mycroft 			spin = 0;
    279  1.25   mycroft 			while (NOT_READY()) {
    280  1.25   mycroft 				if (++spin < sc->sc_spinmax)
    281  1.25   mycroft 					continue;
    282  1.11   mycroft 				tic = 0;
    283  1.12   mycroft 				/* adapt busy-wait algorithm */
    284  1.12   mycroft 				sc->sc_spinmax++;
    285  1.25   mycroft 				while (NOT_READY_ERR()) {
    286  1.11   mycroft 					/* exponential backoff */
    287  1.11   mycroft 					tic = tic + tic + 1;
    288  1.11   mycroft 					if (tic > TIMEOUT)
    289  1.11   mycroft 						tic = TIMEOUT;
    290  1.11   mycroft 					error = tsleep((caddr_t)sc,
    291  1.11   mycroft 					    LPTPRI | PCATCH, "lptpsh", tic);
    292  1.11   mycroft 					if (error != EWOULDBLOCK)
    293  1.11   mycroft 						return error;
    294  1.11   mycroft 				}
    295  1.25   mycroft 				break;
    296  1.11   mycroft 			}
    297  1.11   mycroft 
    298  1.42   thorpej 			bus_space_write_1(iot, ioh, lpt_data, *sc->sc_cp++);
    299  1.44     mikel 			bus_space_write_1(iot, ioh, lpt_control,
    300  1.44     mikel 			    control | LPC_STROBE);
    301  1.11   mycroft 			sc->sc_count--;
    302  1.42   thorpej 			bus_space_write_1(iot, ioh, lpt_control, control);
    303  1.11   mycroft 
    304  1.11   mycroft 			/* adapt busy-wait algorithm */
    305  1.25   mycroft 			if (spin*2 + 16 < sc->sc_spinmax)
    306  1.12   mycroft 				sc->sc_spinmax--;
    307  1.11   mycroft 		}
    308  1.11   mycroft 	} else {
    309  1.11   mycroft 		int s;
    310  1.11   mycroft 
    311  1.11   mycroft 		while (sc->sc_count > 0) {
    312  1.11   mycroft 			/* if the printer is ready for a char, give it one */
    313  1.11   mycroft 			if ((sc->sc_state & LPT_OBUSY) == 0) {
    314  1.44     mikel 				LPRINTF(("%s: write %u\n", sc->sc_dev.dv_xname,
    315  1.38  christos 				    sc->sc_count));
    316  1.11   mycroft 				s = spltty();
    317  1.16   mycroft 				(void) lptintr(sc);
    318  1.11   mycroft 				splx(s);
    319  1.11   mycroft 			}
    320  1.38  christos 			error = tsleep((caddr_t)sc, LPTPRI | PCATCH,
    321  1.38  christos 			    "lptwrite2", 0);
    322  1.38  christos 			if (error)
    323  1.11   mycroft 				return error;
    324  1.11   mycroft 		}
    325  1.11   mycroft 	}
    326  1.11   mycroft 	return 0;
    327   1.1       cgd }
    328   1.1       cgd 
    329   1.1       cgd /*
    330  1.11   mycroft  * Copy a line from user space to a local buffer, then call putc to get the
    331  1.11   mycroft  * chars moved to the output queue.
    332   1.1       cgd  */
    333  1.36   mycroft int
    334  1.38  christos lptwrite(dev, uio, flags)
    335   1.1       cgd 	dev_t dev;
    336   1.1       cgd 	struct uio *uio;
    337  1.38  christos 	int flags;
    338   1.1       cgd {
    339  1.33   thorpej 	struct lpt_softc *sc = lpt_cd.cd_devs[LPTUNIT(dev)];
    340  1.11   mycroft 	size_t n;
    341  1.11   mycroft 	int error = 0;
    342  1.11   mycroft 
    343  1.38  christos 	while ((n = min(LPT_BSIZE, uio->uio_resid)) != 0) {
    344  1.47   thorpej 		uiomove(sc->sc_cp = sc->sc_inbuf, n, uio);
    345  1.11   mycroft 		sc->sc_count = n;
    346  1.46        is 		error = lptpushbytes(sc);
    347  1.11   mycroft 		if (error) {
    348  1.11   mycroft 			/*
    349  1.11   mycroft 			 * Return accurate residual if interrupted or timed
    350  1.11   mycroft 			 * out.
    351  1.11   mycroft 			 */
    352  1.11   mycroft 			uio->uio_resid += sc->sc_count;
    353  1.11   mycroft 			sc->sc_count = 0;
    354  1.11   mycroft 			return error;
    355   1.1       cgd 		}
    356   1.1       cgd 	}
    357  1.11   mycroft 	return 0;
    358   1.1       cgd }
    359   1.1       cgd 
    360   1.1       cgd /*
    361  1.11   mycroft  * Handle printer interrupts which occur when the printer is ready to accept
    362  1.11   mycroft  * another char.
    363   1.1       cgd  */
    364  1.11   mycroft int
    365  1.30       cgd lptintr(arg)
    366  1.30       cgd 	void *arg;
    367   1.1       cgd {
    368  1.30       cgd 	struct lpt_softc *sc = arg;
    369  1.42   thorpej 	bus_space_tag_t iot = sc->sc_iot;
    370  1.42   thorpej 	bus_space_handle_t ioh = sc->sc_ioh;
    371   1.1       cgd 
    372  1.13   mycroft #if 0
    373  1.11   mycroft 	if ((sc->sc_state & LPT_OPEN) == 0)
    374  1.11   mycroft 		return 0;
    375  1.13   mycroft #endif
    376   1.6   mycroft 
    377  1.11   mycroft 	/* is printer online and ready for output */
    378  1.25   mycroft 	if (NOT_READY() && NOT_READY_ERR())
    379  1.11   mycroft 		return 0;
    380   1.6   mycroft 
    381  1.11   mycroft 	if (sc->sc_count) {
    382  1.13   mycroft 		u_char control = sc->sc_control;
    383  1.11   mycroft 		/* send char */
    384  1.42   thorpej 		bus_space_write_1(iot, ioh, lpt_data, *sc->sc_cp++);
    385  1.42   thorpej 		bus_space_write_1(iot, ioh, lpt_control, control | LPC_STROBE);
    386  1.13   mycroft 		sc->sc_count--;
    387  1.42   thorpej 		bus_space_write_1(iot, ioh, lpt_control, control);
    388  1.11   mycroft 		sc->sc_state |= LPT_OBUSY;
    389  1.11   mycroft 	} else
    390  1.11   mycroft 		sc->sc_state &= ~LPT_OBUSY;
    391   1.1       cgd 
    392  1.11   mycroft 	if (sc->sc_count == 0) {
    393   1.1       cgd 		/* none, wake up the top half to get more */
    394   1.1       cgd 		wakeup((caddr_t)sc);
    395  1.11   mycroft 	}
    396  1.11   mycroft 
    397  1.11   mycroft 	return 1;
    398   1.1       cgd }
    399   1.1       cgd 
    400   1.2       cgd int
    401  1.38  christos lptioctl(dev, cmd, data, flag, p)
    402  1.11   mycroft 	dev_t dev;
    403  1.24       cgd 	u_long cmd;
    404  1.11   mycroft 	caddr_t data;
    405  1.11   mycroft 	int flag;
    406  1.38  christos 	struct proc *p;
    407   1.2       cgd {
    408  1.11   mycroft 	int error = 0;
    409   1.2       cgd 
    410   1.2       cgd 	switch (cmd) {
    411   1.2       cgd 	default:
    412   1.2       cgd 		error = ENODEV;
    413   1.2       cgd 	}
    414   1.2       cgd 
    415  1.11   mycroft 	return error;
    416   1.2       cgd }
    417