643 lines
14 KiB
C
643 lines
14 KiB
C
/* $NetBSD: gpib.c,v 1.8 2006/03/29 06:33:50 thorpej Exp $ */
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/*-
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* Copyright (c) 2003 The NetBSD Foundation, Inc.
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* All rights reserved.
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*
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* This code is derived from software contributed to The NetBSD Foundation
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* by Gregory McGarry.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the NetBSD
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* Foundation, Inc. and its contributors.
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* 4. Neither the name of The NetBSD Foundation nor the names of its
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* contributors may be used to endorse or promote products derived
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* from this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
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* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
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* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
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* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*/
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#include <sys/cdefs.h>
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__KERNEL_RCSID(0, "$NetBSD: gpib.c,v 1.8 2006/03/29 06:33:50 thorpej Exp $");
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/conf.h>
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#include <sys/device.h>
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#include <sys/ioctl.h>
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#include <sys/malloc.h>
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#include <sys/proc.h>
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#include <dev/gpib/gpibvar.h>
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#include <dev/gpib/gpibio.h> /* XXX */
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#include "locators.h"
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#define DEBUG
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#ifdef DEBUG
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int gpibdebug = 0xff;
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#define DBG_FOLLOW 0x01
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#define DBG_INTR 0x02
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#define DBG_FAIL 0x04
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#define DPRINTF(mask, str) if (gpibdebug & (mask)) printf str
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#else
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#define DPRINTF(mask, str) /* nothing */
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#endif
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int gpibmatch(struct device *, struct cfdata *, void *);
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void gpibattach(struct device *, struct device *, void *);
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CFATTACH_DECL(gpib, sizeof(struct gpib_softc),
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gpibmatch, gpibattach, NULL, NULL);
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static int gpibsubmatch1(struct device *, struct cfdata *,
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const int *, void *);
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static int gpibsubmatch2(struct device *, struct cfdata *,
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const int *, void *);
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static int gpibprint(void *, const char *);
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dev_type_open(gpibopen);
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dev_type_close(gpibclose);
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dev_type_read(gpibread);
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dev_type_write(gpibwrite);
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dev_type_ioctl(gpibioctl);
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dev_type_poll(gpibpoll);
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const struct cdevsw gpib_cdevsw = {
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gpibopen, gpibclose, gpibread, gpibwrite, gpibioctl,
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nostop, notty, gpibpoll, nommap, nokqfilter,
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};
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extern struct cfdriver gpib_cd;
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#define GPIBUNIT(dev) (minor(dev) & 0x0f)
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int gpibtimeout = 100000; /* # of status tests before we give up */
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int
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gpibmatch(parent, match, aux)
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struct device *parent;
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struct cfdata *match;
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void *aux;
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{
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return (1);
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}
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void
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gpibattach(parent, self, aux)
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struct device *parent, *self;
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void *aux;
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{
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struct gpib_softc *sc = device_private(self);
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struct cfdata *cf = device_cfdata(&sc->sc_dev);
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struct gpibdev_attach_args *gda = aux;
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struct gpib_attach_args ga;
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int address;
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sc->sc_ic = gda->ga_ic;
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/*
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* If the configuration file specified a host address, then
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* use it in favour of registers/switches or the default (30).
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*/
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if (cf->cf_loc[GPIBDEVCF_ADDRESS] != GPIBDEVCF_ADDRESS_DEFAULT)
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sc->sc_myaddr = cf->cf_loc[GPIBDEVCF_ADDRESS];
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else if (gda->ga_address != GPIBDEVCF_ADDRESS_DEFAULT)
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sc->sc_myaddr = gda->ga_address;
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else
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sc->sc_myaddr = 30;
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printf(": host address %d\n", sc->sc_myaddr);
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/* record our softc pointer */
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sc->sc_ic->bus = sc;
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/* Initialize the slave request queue */
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TAILQ_INIT(&sc->sc_queue);
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/* attach addressed devices */
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for (address=0; address<GPIB_NDEVS; address++) {
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ga.ga_ic = sc->sc_ic;
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ga.ga_address = address;
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(void) config_search_ia(gpibsubmatch1, &sc->sc_dev, "gpib", &ga);
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}
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/* attach the wild-carded devices - probably protocol busses */
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ga.ga_ic = sc->sc_ic;
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(void) config_search_ia(gpibsubmatch2, &sc->sc_dev, "gpib", &ga);
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}
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int
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gpibsubmatch1(parent, cf, ldesc, aux)
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struct device *parent;
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struct cfdata *cf;
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const int *ldesc;
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void *aux;
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{
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struct gpib_softc *sc = (struct gpib_softc *)parent;
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struct gpib_attach_args *ga = aux;
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if (cf->cf_loc[GPIBCF_ADDRESS] != ga->ga_address)
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return (0);
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if (cf->cf_loc[GPIBCF_ADDRESS] == sc->sc_myaddr)
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return (0);
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if (config_match(parent, cf, ga) > 0) {
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if (gpib_alloc(sc, ga->ga_address))
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return (0);
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config_attach(parent, cf, ga, gpibprint);
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return (0);
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}
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return (0);
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}
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int
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gpibsubmatch2(parent, cf, aux)
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struct device *parent;
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struct cfdata *cf;
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const int *ldesc;
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void *aux;
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{
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struct gpib_attach_args *ga = aux;
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if (cf->cf_loc[GPIBCF_ADDRESS] != GPIBCF_ADDRESS_DEFAULT)
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return (0);
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ga->ga_address = GPIBCF_ADDRESS_DEFAULT;
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if (config_match(parent, cf, ga) > 0) {
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config_attach(parent, cf, ga, gpibdevprint);
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return (0);
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}
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return (0);
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}
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int
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gpibprint(aux, pnp)
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void *aux;
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const char *pnp;
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{
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struct gpib_attach_args *ga = aux;
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if (ga->ga_address != GPIBCF_ADDRESS_DEFAULT)
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printf(" address %d", ga->ga_address);
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return (UNCONF);
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}
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int
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gpibdevprint(aux, pnp)
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void *aux;
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const char *pnp;
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{
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if (pnp != NULL)
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printf("gpib at %s", pnp);
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return (UNCONF);
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}
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/*
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* Called by hardware driver, pass to device driver.
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*/
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int
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gpibintr(v)
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void *v;
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{
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struct gpib_softc *sc = v;
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gpib_handle_t hdl;
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DPRINTF(DBG_INTR, ("gpibintr: sc=%p\n", sc));
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hdl = TAILQ_FIRST(&sc->sc_queue);
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(hdl->hq_callback)(hdl->hq_softc, GPIBCBF_INTR);
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return (0);
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}
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/*
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* Create a callback handle.
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*/
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int
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_gpibregister(sc, slave, callback, arg, hdl)
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struct gpib_softc *sc;
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int slave;
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gpib_callback_t callback;
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void *arg;
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gpib_handle_t *hdl;
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{
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MALLOC(*hdl, gpib_handle_t, sizeof(struct gpibqueue),
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M_DEVBUF, M_NOWAIT);
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if (*hdl == NULL) {
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DPRINTF(DBG_FAIL, ("_gpibregister: can't allocate queue\n"));
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return (1);
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}
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(*hdl)->hq_slave = slave;
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(*hdl)->hq_callback = callback;
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(*hdl)->hq_softc = arg;
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return (0);
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}
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/*
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* Request exclusive access to the GPIB bus.
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*/
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int
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_gpibrequest(sc, hdl)
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struct gpib_softc *sc;
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gpib_handle_t hdl;
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{
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DPRINTF(DBG_FOLLOW, ("_gpibrequest: sc=%p hdl=%p\n", sc, hdl));
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TAILQ_INSERT_TAIL(&sc->sc_queue, hdl, hq_list);
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if (TAILQ_FIRST(&sc->sc_queue) == hdl)
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return (1);
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return (0);
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}
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/*
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* Release exclusive access to the GPIB bus.
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*/
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void
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_gpibrelease(sc, hdl)
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struct gpib_softc *sc;
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gpib_handle_t hdl;
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{
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DPRINTF(DBG_FOLLOW, ("_gpibrelease: sc=%p hdl=%p\n", sc, hdl));
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TAILQ_REMOVE(&sc->sc_queue, hdl, hq_list);
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if ((hdl = TAILQ_FIRST(&sc->sc_queue)) != NULL)
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(*hdl->hq_callback)(hdl->hq_softc, GPIBCBF_START);
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}
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/*
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* Asynchronous wait.
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*/
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void
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_gpibawait(sc)
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struct gpib_softc *sc;
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{
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int slave;
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DPRINTF(DBG_FOLLOW, ("_gpibawait: sc=%p\n", sc));
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slave = TAILQ_FIRST(&sc->sc_queue)->hq_slave;
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(*sc->sc_ic->ppwatch)(sc->sc_ic->cookie, slave);
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}
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/*
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* Synchronous (spin) wait.
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*/
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int
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_gpibswait(sc, slave)
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struct gpib_softc *sc;
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int slave;
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{
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int timo = gpibtimeout;
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int (*pptest)(void *, int);
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DPRINTF(DBG_FOLLOW, ("_gpibswait: sc=%p\n", sc));
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pptest = sc->sc_ic->pptest;
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while ((*pptest)(sc->sc_ic->cookie, slave) == 0) {
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if (--timo == 0) {
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printf("%s: swait timeout\n", sc->sc_dev.dv_xname);
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return(-1);
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}
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}
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return (0);
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}
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/*
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* Resource accounting: check if the address has already been
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* claimed and allocated.
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*/
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int
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gpib_isalloc(sc, address)
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struct gpib_softc *sc;
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u_int8_t address;
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{
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DPRINTF(DBG_FOLLOW, ("gpib_isalloc: sc=%p address=%d\n", sc, address));
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#ifdef DIAGNOSTIC
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if (address >= GPIB_NDEVS)
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panic("gpib_isalloc: device address out of range");
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#endif
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return ((sc->sc_rmap & (1 << address)) != 0);
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}
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/*
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* Resource accounting: allocate the address.
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*/
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int
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gpib_alloc(sc, address)
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struct gpib_softc *sc;
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u_int8_t address;
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{
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DPRINTF(DBG_FOLLOW, ("gpib_alloc: sc=%p address=%d\n", sc, address));
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#ifdef DIAGNOSTIC
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if (address >= GPIB_NDEVS)
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panic("gpib_alloc: device address out of range");
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#endif
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if (!gpib_isalloc(sc, address)) {
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sc->sc_rmap |= (1 << address);
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return (0);
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}
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return (1);
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}
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/*
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* Resource accounting: deallocate the address.
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*/
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void
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gpib_dealloc(sc, address)
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struct gpib_softc *sc;
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u_int8_t address;
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{
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DPRINTF(DBG_FOLLOW, ("gpib_free: sc=%p address=%d\n", sc, address));
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#ifdef DIAGNOSTIC
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if (address >= GPIB_NDEVS)
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panic("gpib_free: device address out of range");
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if (!gpib_isalloc(sc, address))
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panic("gpib_free: not allocated");
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#endif
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sc->sc_rmap &= ~(1 << address);
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}
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int
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_gpibsend(sc, slave, sec, ptr, origcnt)
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struct gpib_softc *sc;
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int slave;
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int sec;
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void *ptr;
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int origcnt;
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{
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int rv;
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int cnt = 0;
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u_int8_t cmds[4];
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int i = 0;
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DPRINTF(DBG_FOLLOW,
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("_gpibsend: sc=%p slave %d sec=%d ptr=%p cnt=%d\n",
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sc, slave, sec, ptr, origcnt));
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/*
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* For compatibility, call the hardware driver directly.
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*/
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if (sc->sc_ic->send != NULL) {
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rv = (*sc->sc_ic->send)(sc->sc_ic->cookie,
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slave, sec, ptr, origcnt);
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return (rv);
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}
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if ((*sc->sc_ic->tc)(sc->sc_ic->cookie, 0))
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goto senderror;
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cmds[i++] = GPIBCMD_UNL;
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cmds[i++] = GPIBCMD_TAG | sc->sc_myaddr;
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cmds[i++] = GPIBCMD_LAG | slave;
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if (sec >= 0 || sec == -2) {
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if (sec == -2) /* selected device clear KLUDGE */
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cmds[i++] = GPIBCMD_SDC;
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else
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cmds[i++] = GPIBCMD_SCG | sec;
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}
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if ((*sc->sc_ic->sendcmds)(sc->sc_ic->cookie, cmds, i) != i)
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goto senderror;
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if ((*sc->sc_ic->gts)(sc->sc_ic->cookie))
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goto senderror;
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if (origcnt) {
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cnt = (*sc->sc_ic->senddata)(sc->sc_ic->cookie, ptr, origcnt);
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if (cnt != origcnt)
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goto senderror;
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if ((*sc->sc_ic->tc)(sc->sc_ic->cookie, 0))
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goto senderror;
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}
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return (origcnt);
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senderror:
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(*sc->sc_ic->ifc)(sc->sc_ic->cookie);
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DPRINTF(DBG_FAIL,
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("%s: _gpibsend failed: slave %d, sec %x, sent %d of %d bytes\n",
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sc->sc_dev.dv_xname, slave, sec, cnt, origcnt));
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return (cnt);
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}
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int
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_gpibrecv(sc, slave, sec, ptr, origcnt)
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struct gpib_softc *sc;
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int slave;
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int sec;
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void *ptr;
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int origcnt;
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{
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int rv;
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u_int8_t cmds[4];
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int cnt = 0;
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int i = 0;
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DPRINTF(DBG_FOLLOW,
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("_gpibrecv: sc=%p slave=%d sec=%d buf=%p cnt=%d\n",
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sc, slave, sec, ptr, origcnt));
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/*
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* For compatibility, call the hardware driver directly.
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*/
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if (sc->sc_ic->recv != NULL) {
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rv = (*sc->sc_ic->recv)(sc->sc_ic->cookie,
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slave, sec, ptr, origcnt);
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return (rv);
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}
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/*
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* slave < 0 implies continuation of a previous receive
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* that probably timed out.
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*/
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if (slave >= 0) {
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if ((*sc->sc_ic->tc)(sc->sc_ic->cookie, 0))
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goto recverror;
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cmds[i++] = GPIBCMD_UNL;
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cmds[i++] = GPIBCMD_LAG | sc->sc_myaddr;
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cmds[i++] = GPIBCMD_TAG | slave;
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if (sec >= 0)
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cmds[i++] = GPIBCMD_SCG | sec;
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if ((*sc->sc_ic->sendcmds)(sc->sc_ic->cookie, cmds, i) != i)
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goto recverror;
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if ((*sc->sc_ic->gts)(sc->sc_ic->cookie))
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goto recverror;
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}
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if (origcnt) {
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cnt = (*sc->sc_ic->recvdata)(sc->sc_ic->cookie, ptr, origcnt);
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if (cnt != origcnt)
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goto recverror;
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if ((sc->sc_ic->tc)(sc->sc_ic->cookie, 0))
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goto recverror;
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cmds[0] = (slave == GPIB_BROADCAST_ADDR) ?
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GPIBCMD_UNA : GPIBCMD_UNT;
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if ((*sc->sc_ic->sendcmds)(sc->sc_ic->cookie, cmds, 1) != 1)
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goto recverror;
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}
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return (origcnt);
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recverror:
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(*sc->sc_ic->ifc)(sc->sc_ic->cookie);
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DPRINTF(DBG_FAIL,
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("_gpibrecv: failed, sc=%p slave %d, sec %x, got %d of %d bytes\n",
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sc, slave, sec, cnt, origcnt));
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return (cnt);
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}
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/*
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* /dev/gpib? interface
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*/
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int
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gpibopen(dev, flags, mode, p)
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dev_t dev;
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int flags, mode;
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struct proc *p;
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{
|
|
struct gpib_softc *sc;
|
|
|
|
sc = device_lookup(&gpib_cd, GPIBUNIT(dev));
|
|
if (sc == NULL)
|
|
return (ENXIO);
|
|
|
|
DPRINTF(DBG_FOLLOW, ("gpibopen: sc=%p\n", sc));
|
|
|
|
if (sc->sc_flags & GPIBF_ACTIVE)
|
|
return (EBUSY);
|
|
sc->sc_flags |= GPIBF_ACTIVE;
|
|
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
gpibclose(dev, flag, mode, p)
|
|
dev_t dev;
|
|
int flag, mode;
|
|
struct proc *p;
|
|
{
|
|
struct gpib_softc *sc;
|
|
|
|
sc = device_lookup(&gpib_cd, GPIBUNIT(dev));
|
|
if (sc == NULL)
|
|
return (ENXIO);
|
|
|
|
DPRINTF(DBG_FOLLOW, ("gpibclose: sc=%p\n", sc));
|
|
|
|
sc->sc_flags &= ~GPIBF_ACTIVE;
|
|
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
gpibread(dev, uio, flags)
|
|
dev_t dev;
|
|
struct uio *uio;
|
|
int flags;
|
|
{
|
|
struct gpib_softc *sc;
|
|
|
|
sc = device_lookup(&gpib_cd, GPIBUNIT(dev));
|
|
if (sc == NULL)
|
|
return (ENXIO);
|
|
|
|
DPRINTF(DBG_FOLLOW, ("gpibread: sc=%p\n", sc));
|
|
|
|
return (EOPNOTSUPP);
|
|
}
|
|
|
|
int
|
|
gpibwrite(dev, uio, flags)
|
|
dev_t dev;
|
|
struct uio *uio;
|
|
int flags;
|
|
{
|
|
struct gpib_softc *sc;
|
|
|
|
sc = device_lookup(&gpib_cd, GPIBUNIT(dev));
|
|
if (sc == NULL)
|
|
return (ENXIO);
|
|
|
|
DPRINTF(DBG_FOLLOW, ("gpibwrite: sc=%p\n", sc));
|
|
|
|
return (EOPNOTSUPP);
|
|
}
|
|
|
|
int
|
|
gpibioctl(dev, cmd, data, flag, p)
|
|
dev_t dev;
|
|
u_long cmd;
|
|
caddr_t data;
|
|
int flag;
|
|
struct proc *p;
|
|
{
|
|
struct gpib_softc *sc;
|
|
|
|
sc = device_lookup(&gpib_cd, GPIBUNIT(dev));
|
|
if (sc == NULL)
|
|
return (ENXIO);
|
|
|
|
DPRINTF(DBG_FOLLOW, ("gpibioctl(%lu, '%c',%lu): sc=%p\n",
|
|
IOCPARM_LEN(cmd), (char)IOCGROUP(cmd), cmd & 0xff, sc));
|
|
|
|
switch (cmd) {
|
|
case GPIB_INFO:
|
|
(*(int *)data) = 0xa5a5a5a5;
|
|
break;
|
|
}
|
|
|
|
return (EINVAL);
|
|
}
|
|
|
|
int
|
|
gpibpoll(dev, events, p)
|
|
dev_t dev;
|
|
int events;
|
|
struct proc *p;
|
|
{
|
|
struct gpib_softc *sc;
|
|
|
|
sc = device_lookup(&gpib_cd, GPIBUNIT(dev));
|
|
if (sc == NULL)
|
|
return (ENXIO);
|
|
|
|
DPRINTF(DBG_FOLLOW, ("gpibpoll: sc=%p\n", sc));
|
|
|
|
return (0);
|
|
}
|