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authorPer Fogelstrom <pefo@cvs.openbsd.org>1996-06-24 20:10:35 +0000
committerPer Fogelstrom <pefo@cvs.openbsd.org>1996-06-24 20:10:35 +0000
commit266b9269b750ddda9f58181eabac840982b9fe99 (patch)
tree228521cee8bdc45599d042a6cc7d0fe110c3dd69 /sys
parent96023c2b1bc9f556f270159549d432f65b831701 (diff)
local version of isa/lpt.c
Diffstat (limited to 'sys')
-rw-r--r--sys/arch/arc/dev/lpr.c675
1 files changed, 675 insertions, 0 deletions
diff --git a/sys/arch/arc/dev/lpr.c b/sys/arch/arc/dev/lpr.c
new file mode 100644
index 00000000000..75f8f99f9d6
--- /dev/null
+++ b/sys/arch/arc/dev/lpr.c
@@ -0,0 +1,675 @@
+/* $OpenBSD: lpr.c,v 1.1 1996/06/24 20:10:34 pefo Exp $ */
+
+/*
+ * Copyright (c) 1993, 1994 Charles Hannum.
+ * Copyright (c) 1990 William F. Jolitz, TeleMuse
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This software is a component of "386BSD" developed by
+ * William F. Jolitz, TeleMuse.
+ * 4. Neither the name of the developer nor the name "386BSD"
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS A COMPONENT OF 386BSD DEVELOPED BY WILLIAM F. JOLITZ
+ * AND IS INTENDED FOR RESEARCH AND EDUCATIONAL PURPOSES ONLY. THIS
+ * SOFTWARE SHOULD NOT BE CONSIDERED TO BE A COMMERCIAL PRODUCT.
+ * THE DEVELOPER URGES THAT USERS WHO REQUIRE A COMMERCIAL PRODUCT
+ * NOT MAKE USE OF THIS WORK.
+ *
+ * FOR USERS WHO WISH TO UNDERSTAND THE 386BSD SYSTEM DEVELOPED
+ * BY WILLIAM F. JOLITZ, WE RECOMMEND THE USER STUDY WRITTEN
+ * REFERENCES SUCH AS THE "PORTING UNIX TO THE 386" SERIES
+ * (BEGINNING JANUARY 1991 "DR. DOBBS JOURNAL", USA AND BEGINNING
+ * JUNE 1991 "UNIX MAGAZIN", GERMANY) BY WILLIAM F. JOLITZ AND
+ * LYNNE GREER JOLITZ, AS WELL AS OTHER BOOKS ON UNIX AND THE
+ * ON-LINE 386BSD USER MANUAL BEFORE USE. A BOOK DISCUSSING THE INTERNALS
+ * OF 386BSD ENTITLED "386BSD FROM THE INSIDE OUT" WILL BE AVAILABLE LATE 1992.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE DEVELOPER ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE DEVELOPER BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/*
+ * Device Driver for AT parallel printer port
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/proc.h>
+#include <sys/user.h>
+#include <sys/buf.h>
+#include <sys/kernel.h>
+#include <sys/ioctl.h>
+#include <sys/uio.h>
+#include <sys/device.h>
+#include <sys/conf.h>
+#include <sys/syslog.h>
+
+#include <machine/bus.h>
+#include <machine/intr.h>
+
+#include <dev/isa/isavar.h>
+#include <dev/isa/lptreg.h>
+
+#include <lpr.h>
+
+#define TIMEOUT hz*16 /* wait up to 16 seconds for a ready */
+#define STEP hz/4
+
+#define LPTPRI (PZERO+8)
+#define LPT_BSIZE 1024
+
+#if !defined(DEBUG) || !defined(notdef)
+#define LPRINTF(a)
+#else
+#define LPRINTF if (lprdebug) printf a
+int lprdebug = 1;
+#endif
+
+struct lpr_softc {
+ struct device sc_dev;
+ void *sc_ih;
+
+ size_t sc_count;
+ struct buf *sc_inbuf;
+ u_char *sc_cp;
+ int sc_spinmax;
+ int sc_iobase;
+ bus_chipset_tag_t sc_bc;
+ bus_io_handle_t sc_ioh;
+ int sc_irq;
+ u_char sc_state;
+#define LPT_OPEN 0x01 /* device is open */
+#define LPT_OBUSY 0x02 /* printer is busy doing output */
+#define LPT_INIT 0x04 /* waiting to initialize for open */
+ u_char sc_flags;
+#define LPT_AUTOLF 0x20 /* automatic LF on CR */
+#define LPT_NOPRIME 0x40 /* don't prime on open */
+#define LPT_NOINTR 0x80 /* do not use interrupt */
+ u_char sc_control;
+ u_char sc_laststatus;
+};
+
+/* XXX does not belong here */
+cdev_decl(lpr);
+
+int lprintr __P((void *));
+
+#if NLPR_ISA
+int lpr_isa_probe __P((struct device *, void *, void *));
+void lpr_isa_attach __P((struct device *, struct device *, void *));
+struct cfattach lpr_ca = {
+ sizeof(struct lpr_softc), lpr_isa_probe, lpr_isa_attach
+};
+#endif
+
+#if NLPR_PICA
+int lpr_pica_probe __P((struct device *, void *, void *));
+void lpr_pica_attach __P((struct device *, struct device *, void *));
+struct cfattach lpr_pica_ca = {
+ sizeof(struct lpr_softc), lpr_pica_probe, lpr_pica_attach
+};
+#endif
+
+struct cfdriver lpr_cd = {
+ NULL, "lpr", DV_TTY
+};
+
+#define LPTUNIT(s) (minor(s) & 0x1f)
+#define LPTFLAGS(s) (minor(s) & 0xe0)
+
+#define LPS_INVERT (LPS_SELECT|LPS_NERR|LPS_NBSY|LPS_NACK)
+#define LPS_MASK (LPS_SELECT|LPS_NERR|LPS_NBSY|LPS_NACK|LPS_NOPAPER)
+#define NOT_READY() ((bus_io_read_1(bc, ioh, lpt_status) ^ LPS_INVERT) & LPS_MASK)
+#define NOT_READY_ERR() not_ready(bus_io_read_1(bc, ioh, lpt_status), sc)
+static int not_ready __P((u_char, struct lpr_softc *));
+
+static void lprwakeup __P((void *arg));
+static int pushbytes __P((struct lpr_softc *));
+
+int lpr_port_test __P((bus_chipset_tag_t, bus_io_handle_t, bus_io_addr_t,
+ bus_io_size_t, u_char, u_char));
+
+/*
+ * Internal routine to lprprobe to do port tests of one byte value.
+ */
+int
+lpr_port_test(bc, ioh, base, off, data, mask)
+ bus_chipset_tag_t bc;
+ bus_io_handle_t ioh;
+ bus_io_addr_t base;
+ bus_io_size_t off;
+ u_char data, mask;
+{
+ int timeout;
+ u_char temp;
+
+ data &= mask;
+ bus_io_write_1(bc, ioh, off, data);
+ timeout = 1000;
+ do {
+ delay(10);
+ temp = bus_io_read_1(bc, ioh, off) & mask;
+ } while (temp != data && --timeout);
+ LPRINTF(("lpr: port=0x%x out=0x%x in=0x%x timeout=%d\n", base + off,
+ data, temp, timeout));
+ return (temp == data);
+}
+
+/*
+ * Logic:
+ * 1) You should be able to write to and read back the same value
+ * to the data port. Do an alternating zeros, alternating ones,
+ * walking zero, and walking one test to check for stuck bits.
+ *
+ * 2) You should be able to write to and read back the same value
+ * to the control port lower 5 bits, the upper 3 bits are reserved
+ * per the IBM PC technical reference manauls and different boards
+ * do different things with them. Do an alternating zeros, alternating
+ * ones, walking zero, and walking one test to check for stuck bits.
+ *
+ * Some printers drag the strobe line down when the are powered off
+ * so this bit has been masked out of the control port test.
+ *
+ * XXX Some printers may not like a fast pulse on init or strobe, I
+ * don't know at this point, if that becomes a problem these bits
+ * should be turned off in the mask byte for the control port test.
+ *
+ * 3) Set the data and control ports to a value of 0
+ */
+#if NLPR_ISA
+int
+lpr_isa_probe(parent, match, aux)
+ struct device *parent;
+ void *match, *aux;
+{
+ struct isa_attach_args *ia = aux;
+ bus_chipset_tag_t bc;
+ bus_io_handle_t ioh;
+ u_long base;
+ u_char mask, data;
+ int i, rv;
+
+#ifdef DEBUG
+#define ABORT do {printf("lprprobe: mask %x data %x failed\n", mask, data); \
+ goto out;} while (0)
+#else
+#define ABORT goto out
+#endif
+
+ bc = ia->ia_bc;
+ base = ia->ia_iobase;
+ if (bus_io_map(bc, base, LPT_NPORTS, &ioh))
+ return 0;
+
+ rv = 0;
+ mask = 0xff;
+
+ data = 0x55; /* Alternating zeros */
+ if (!lpr_port_test(bc, ioh, base, lpt_data, data, mask))
+ ABORT;
+
+ data = 0xaa; /* Alternating ones */
+ if (!lpr_port_test(bc, ioh, base, lpt_data, data, mask))
+ ABORT;
+
+ for (i = 0; i < CHAR_BIT; i++) { /* Walking zero */
+ data = ~(1 << i);
+ if (!lpr_port_test(bc, ioh, base, lpt_data, data, mask))
+ ABORT;
+ }
+
+ for (i = 0; i < CHAR_BIT; i++) { /* Walking one */
+ data = (1 << i);
+ if (!lpr_port_test(bc, ioh, base, lpt_data, data, mask))
+ ABORT;
+ }
+
+ bus_io_write_1(bc, ioh, lpt_data, 0);
+ bus_io_write_1(bc, ioh, lpt_control, 0);
+
+ ia->ia_iosize = LPT_NPORTS;
+ ia->ia_msize = 0;
+
+ rv = 1;
+
+out:
+ bus_io_unmap(bc, ioh, LPT_NPORTS);
+ return rv;
+}
+#endif
+
+#if NLPR_PICA
+int
+lpr_pica_probe(parent, match, aux)
+ struct device *parent;
+ void *match, *aux;
+{
+ struct confargs *ca = aux;
+ bus_chipset_tag_t bc;
+ bus_io_handle_t ioh;
+ u_long base;
+ u_char mask, data;
+ int i;
+
+#ifdef DEBUG
+#define ABORT do {printf("lprprobe: mask %x data %x failed\n", mask, data); \
+ return 0;} while (0)
+#else
+#define ABORT return 0
+#endif
+
+ if(!BUS_MATCHNAME(ca, "lpr"))
+ return(0);
+
+ bc = 0;
+ base = (int)BUS_CVTADDR(ca);
+ ioh = base;
+
+ mask = 0xff;
+
+ data = 0x55; /* Alternating zeros */
+ if (!lpr_port_test(bc, ioh, base, lpt_data, data, mask))
+ ABORT;
+
+ data = 0xaa; /* Alternating ones */
+ if (!lpr_port_test(bc, ioh, base, lpt_data, data, mask))
+ ABORT;
+
+ for (i = 0; i < CHAR_BIT; i++) { /* Walking zero */
+ data = ~(1 << i);
+ if (!lpr_port_test(bc, ioh, base, lpt_data, data, mask))
+ ABORT;
+ }
+
+ for (i = 0; i < CHAR_BIT; i++) { /* Walking one */
+ data = (1 << i);
+ if (!lpr_port_test(bc, ioh, base, lpt_data, data, mask))
+ ABORT;
+ }
+
+ bus_io_write_1(bc, ioh, lpt_data, 0);
+ bus_io_write_1(bc, ioh, lpt_control, 0);
+
+ return 1;
+}
+#endif
+
+#if NLPR_ISA
+void
+lpr_isa_attach(parent, self, aux)
+ struct device *parent, *self;
+ void *aux;
+{
+ struct lpr_softc *sc = (void *)self;
+ struct isa_attach_args *ia = aux;
+ bus_chipset_tag_t bc;
+ bus_io_handle_t ioh;
+
+ if (ia->ia_irq != IRQUNK)
+ printf("\n");
+ else
+ printf(": polled\n");
+
+ sc->sc_iobase = ia->ia_iobase;
+ sc->sc_irq = ia->ia_irq;
+ sc->sc_state = 0;
+
+ bc = sc->sc_bc = ia->ia_bc;
+ if (bus_io_map(bc, sc->sc_iobase, LPT_NPORTS, &ioh))
+ panic("lprattach: couldn't map I/O ports");
+ sc->sc_ioh = ioh;
+
+ bus_io_write_1(bc, ioh, lpt_control, LPC_NINIT);
+
+ if (ia->ia_irq != IRQUNK)
+ sc->sc_ih = isa_intr_establish(ia->ia_ic, ia->ia_irq, IST_EDGE,
+ IPL_TTY, lprintr, sc, sc->sc_dev.dv_xname);
+}
+#endif
+
+#if NLPR_PICA
+void
+lpr_pica_attach(parent, self, aux)
+ struct device *parent, *self;
+ void *aux;
+{
+ struct lpr_softc *sc = (void *)self;
+ struct confargs *ca = aux;
+ bus_chipset_tag_t bc;
+ bus_io_handle_t ioh;
+
+ printf("\n");
+
+ sc->sc_iobase = (int)BUS_CVTADDR(ca);
+ sc->sc_irq = 0;
+ sc->sc_state = 0;
+
+ bc = sc->sc_bc = 0;
+ sc->sc_ioh = sc->sc_iobase;
+
+ bus_io_write_1(bc, ioh, lpt_control, LPC_NINIT);
+
+ BUS_INTR_ESTABLISH(ca, lprintr, sc);
+}
+#endif
+
+/*
+ * Reset the printer, then wait until it's selected and not busy.
+ */
+int
+lpropen(dev, flag, mode, p)
+ dev_t dev;
+ int flag;
+ int mode;
+ struct proc *p;
+{
+ int unit = LPTUNIT(dev);
+ u_char flags = LPTFLAGS(dev);
+ struct lpr_softc *sc;
+ bus_chipset_tag_t bc;
+ bus_io_handle_t ioh;
+ u_char control;
+ int error;
+ int spin;
+
+ if (unit >= lpr_cd.cd_ndevs)
+ return ENXIO;
+ sc = lpr_cd.cd_devs[unit];
+ if (!sc)
+ return ENXIO;
+
+ if (sc->sc_irq == IRQUNK && (flags & LPT_NOINTR) == 0)
+ return ENXIO;
+
+#ifdef DIAGNOSTIC
+ if (sc->sc_state)
+ printf("%s: stat=0x%x not zero\n", sc->sc_dev.dv_xname,
+ sc->sc_state);
+#endif
+
+ if (sc->sc_state)
+ return EBUSY;
+
+ sc->sc_state = LPT_INIT;
+ sc->sc_flags = flags;
+ LPRINTF(("%s: open: flags=0x%x\n", sc->sc_dev.dv_xname, flags));
+ bc = sc->sc_bc;
+ ioh = sc->sc_ioh;
+
+ if ((flags & LPT_NOPRIME) == 0) {
+ /* assert INIT for 100 usec to start up printer */
+ bus_io_write_1(bc, ioh, lpt_control, LPC_SELECT);
+ delay(100);
+ }
+
+ control = LPC_SELECT | LPC_NINIT;
+ bus_io_write_1(bc, ioh, lpt_control, control);
+
+ /* wait till ready (printer running diagnostics) */
+ for (spin = 0; NOT_READY_ERR(); spin += STEP) {
+ if (spin >= TIMEOUT) {
+ sc->sc_state = 0;
+ return EBUSY;
+ }
+
+ /* wait 1/4 second, give up if we get a signal */
+ error = tsleep((caddr_t)sc, LPTPRI | PCATCH, "lpropen", STEP);
+ if (error != EWOULDBLOCK) {
+ sc->sc_state = 0;
+ return error;
+ }
+ }
+
+ if ((flags & LPT_NOINTR) == 0)
+ control |= LPC_IENABLE;
+ if (flags & LPT_AUTOLF)
+ control |= LPC_AUTOLF;
+ sc->sc_control = control;
+ bus_io_write_1(bc, ioh, lpt_control, control);
+
+ sc->sc_inbuf = geteblk(LPT_BSIZE);
+ sc->sc_count = 0;
+ sc->sc_state = LPT_OPEN;
+
+ if ((sc->sc_flags & LPT_NOINTR) == 0)
+ lprwakeup(sc);
+
+ LPRINTF(("%s: opened\n", sc->sc_dev.dv_xname));
+ return 0;
+}
+
+int
+not_ready(status, sc)
+ u_char status;
+ struct lpr_softc *sc;
+{
+ u_char new;
+
+ status = (status ^ LPS_INVERT) & LPS_MASK;
+ new = status & ~sc->sc_laststatus;
+ sc->sc_laststatus = status;
+
+ if (new & LPS_SELECT)
+ log(LOG_NOTICE, "%s: offline\n", sc->sc_dev.dv_xname);
+ else if (new & LPS_NOPAPER)
+ log(LOG_NOTICE, "%s: out of paper\n", sc->sc_dev.dv_xname);
+ else if (new & LPS_NERR)
+ log(LOG_NOTICE, "%s: output error\n", sc->sc_dev.dv_xname);
+
+ return status;
+}
+
+void
+lprwakeup(arg)
+ void *arg;
+{
+ struct lpr_softc *sc = arg;
+ int s;
+
+ s = spltty();
+ lprintr(sc);
+ splx(s);
+
+ timeout(lprwakeup, sc, STEP);
+}
+
+/*
+ * Close the device, and free the local line buffer.
+ */
+int
+lprclose(dev, flag, mode, p)
+ dev_t dev;
+ int flag;
+ int mode;
+ struct proc *p;
+{
+ int unit = LPTUNIT(dev);
+ struct lpr_softc *sc = lpr_cd.cd_devs[unit];
+ bus_chipset_tag_t bc = sc->sc_bc;
+ bus_io_handle_t ioh = sc->sc_ioh;
+
+ if (sc->sc_count)
+ (void) pushbytes(sc);
+
+ if ((sc->sc_flags & LPT_NOINTR) == 0)
+ untimeout(lprwakeup, sc);
+
+ bus_io_write_1(bc, ioh, lpt_control, LPC_NINIT);
+ sc->sc_state = 0;
+ bus_io_write_1(bc, ioh, lpt_control, LPC_NINIT);
+ brelse(sc->sc_inbuf);
+
+ LPRINTF(("%s: closed\n", sc->sc_dev.dv_xname));
+ return 0;
+}
+
+int
+pushbytes(sc)
+ struct lpr_softc *sc;
+{
+ bus_chipset_tag_t bc = sc->sc_bc;
+ bus_io_handle_t ioh = sc->sc_ioh;
+ int error;
+
+ if (sc->sc_flags & LPT_NOINTR) {
+ int spin, tic;
+ u_char control = sc->sc_control;
+
+ while (sc->sc_count > 0) {
+ spin = 0;
+ while (NOT_READY()) {
+ if (++spin < sc->sc_spinmax)
+ continue;
+ tic = 0;
+ /* adapt busy-wait algorithm */
+ sc->sc_spinmax++;
+ while (NOT_READY_ERR()) {
+ /* exponential backoff */
+ tic = tic + tic + 1;
+ if (tic > TIMEOUT)
+ tic = TIMEOUT;
+ error = tsleep((caddr_t)sc,
+ LPTPRI | PCATCH, "lprpsh", tic);
+ if (error != EWOULDBLOCK)
+ return error;
+ }
+ break;
+ }
+
+ bus_io_write_1(bc, ioh, lpt_data, *sc->sc_cp++);
+ bus_io_write_1(bc, ioh, lpt_control, control | LPC_STROBE);
+ sc->sc_count--;
+ bus_io_write_1(bc, ioh, lpt_control, control);
+
+ /* adapt busy-wait algorithm */
+ if (spin*2 + 16 < sc->sc_spinmax)
+ sc->sc_spinmax--;
+ }
+ } else {
+ int s;
+
+ while (sc->sc_count > 0) {
+ /* if the printer is ready for a char, give it one */
+ if ((sc->sc_state & LPT_OBUSY) == 0) {
+ LPRINTF(("%s: write %d\n", sc->sc_dev.dv_xname,
+ sc->sc_count));
+ s = spltty();
+ (void) lprintr(sc);
+ splx(s);
+ }
+ error = tsleep((caddr_t)sc, LPTPRI | PCATCH,
+ "lprwrite2", 0);
+ if (error)
+ return error;
+ }
+ }
+ return 0;
+}
+
+/*
+ * Copy a line from user space to a local buffer, then call putc to get the
+ * chars moved to the output queue.
+ */
+int
+lprwrite(dev, uio, flags)
+ dev_t dev;
+ struct uio *uio;
+ int flags;
+{
+ struct lpr_softc *sc = lpr_cd.cd_devs[LPTUNIT(dev)];
+ size_t n;
+ int error = 0;
+
+ while ((n = min(LPT_BSIZE, uio->uio_resid)) != 0) {
+ uiomove(sc->sc_cp = sc->sc_inbuf->b_data, n, uio);
+ sc->sc_count = n;
+ error = pushbytes(sc);
+ if (error) {
+ /*
+ * Return accurate residual if interrupted or timed
+ * out.
+ */
+ uio->uio_resid += sc->sc_count;
+ sc->sc_count = 0;
+ return error;
+ }
+ }
+ return 0;
+}
+
+/*
+ * Handle printer interrupts which occur when the printer is ready to accept
+ * another char.
+ */
+int
+lprintr(arg)
+ void *arg;
+{
+ struct lpr_softc *sc = arg;
+ bus_chipset_tag_t bc = sc->sc_bc;
+ bus_io_handle_t ioh = sc->sc_ioh;
+
+ if (((sc->sc_state & LPT_OPEN) == 0 && sc->sc_count == 0) || (sc->sc_flags & LPT_NOINTR))
+ return 0;
+
+ /* is printer online and ready for output */
+ if (NOT_READY() && NOT_READY_ERR())
+ return -1;
+
+ if (sc->sc_count) {
+ u_char control = sc->sc_control;
+ /* send char */
+ bus_io_write_1(bc, ioh, lpt_data, *sc->sc_cp++);
+ bus_io_write_1(bc, ioh, lpt_control, control | LPC_STROBE);
+ sc->sc_count--;
+ bus_io_write_1(bc, ioh, lpt_control, control);
+ sc->sc_state |= LPT_OBUSY;
+ } else
+ sc->sc_state &= ~LPT_OBUSY;
+
+ if (sc->sc_count == 0) {
+ /* none, wake up the top half to get more */
+ wakeup((caddr_t)sc);
+ }
+
+ return 1;
+}
+
+int
+lprioctl(dev, cmd, data, flag, p)
+ dev_t dev;
+ u_long cmd;
+ caddr_t data;
+ int flag;
+ struct proc *p;
+{
+ int error = 0;
+
+ switch (cmd) {
+ default:
+ error = ENODEV;
+ }
+
+ return error;
+}