root/sys/dev/ppbus/ppi.c
/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 1997, 1998, 1999 Nicolas Souchu, Michael Smith
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 AUTHOR OR CONTRIBUTORS 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.
 *
 *
 */

#include <sys/cdefs.h>
#include "opt_ppb_1284.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/module.h>
#include <sys/bus.h>
#include <sys/conf.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/sx.h>
#include <sys/uio.h>
#include <sys/fcntl.h>

#include <machine/bus.h>
#include <machine/resource.h>
#include <sys/rman.h>

#include <dev/ppbus/ppbconf.h>
#include <dev/ppbus/ppb_msq.h>

#ifdef PERIPH_1284
#include <sys/malloc.h>
#include <dev/ppbus/ppb_1284.h>
#endif

#include <dev/ppbus/ppi.h>

#include "ppbus_if.h"

#include <dev/ppbus/ppbio.h>

#define BUFSIZE         512

struct ppi_data {
    device_t    ppi_device;
    struct cdev *ppi_cdev;
    struct sx   ppi_lock;
    int         ppi_flags;
#define HAVE_PPBUS      (1<<0)

    int         ppi_mode;                       /* IEEE1284 mode */
    char        ppi_buffer[BUFSIZE];

#ifdef PERIPH_1284
    struct resource *intr_resource;     /* interrupt resource */
    void *intr_cookie;                  /* interrupt registration cookie */
#endif /* PERIPH_1284 */
};

#define DEVTOSOFTC(dev) \
        ((struct ppi_data *)device_get_softc(dev))

#ifdef PERIPH_1284
static void     ppiintr(void *arg);
#endif

static  d_open_t        ppiopen;
static  d_close_t       ppiclose;
static  d_ioctl_t       ppiioctl;
static  d_write_t       ppiwrite;
static  d_read_t        ppiread;

static struct cdevsw ppi_cdevsw = {
        .d_version =    D_VERSION,
        .d_open =       ppiopen,
        .d_close =      ppiclose,
        .d_read =       ppiread,
        .d_write =      ppiwrite,
        .d_ioctl =      ppiioctl,
        .d_name =       "ppi",
};

#ifdef PERIPH_1284

static void
ppi_enable_intr(device_t ppidev)
{
        char r;
        device_t ppbus = device_get_parent(ppidev);

        r = ppb_rctr(ppbus);
        ppb_wctr(ppbus, r | IRQENABLE);

        return;
}

static void
ppi_disable_intr(device_t ppidev)
{
        char r;
        device_t ppbus = device_get_parent(ppidev);

        r = ppb_rctr(ppbus);
        ppb_wctr(ppbus, r & ~IRQENABLE);

        return;
}

#endif /* PERIPH_1284 */

static void
ppi_identify(driver_t *driver, device_t parent)
{

        device_t dev;

        dev = device_find_child(parent, "ppi", DEVICE_UNIT_ANY);
        if (!dev)
                BUS_ADD_CHILD(parent, 0, "ppi", DEVICE_UNIT_ANY);
}

/*
 * ppi_probe()
 */
static int
ppi_probe(device_t dev)
{
        /* probe is always ok */
        device_set_desc(dev, "Parallel I/O");

        return (0);
}

/*
 * ppi_attach()
 */
static int
ppi_attach(device_t dev)
{
        struct ppi_data *ppi = DEVTOSOFTC(dev);
#ifdef PERIPH_1284
        int error, rid = 0;

        /* declare our interrupt handler */
        ppi->intr_resource = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
            RF_ACTIVE);
        if (ppi->intr_resource) {
                /* register our interrupt handler */
                error = bus_setup_intr(dev, ppi->intr_resource,
                    INTR_TYPE_TTY | INTR_MPSAFE, NULL, ppiintr, dev,
                    &ppi->intr_cookie);
                if (error) {
                        bus_release_resource(dev, SYS_RES_IRQ, rid,
                            ppi->intr_resource);
                        device_printf(dev,
                            "Unable to register interrupt handler\n");
                        return (error);
                }
        }
#endif /* PERIPH_1284 */

        sx_init(&ppi->ppi_lock, "ppi");
        ppi->ppi_cdev = make_dev(&ppi_cdevsw, device_get_unit(dev),
                 UID_ROOT, GID_WHEEL,
                 0600, "ppi%d", device_get_unit(dev));
        if (ppi->ppi_cdev == NULL) {
                device_printf(dev, "Failed to create character device\n");
                return (ENXIO);
        }
        ppi->ppi_cdev->si_drv1 = ppi;
        ppi->ppi_device = dev;

        return (0);
}

static int
ppi_detach(device_t dev)
{
        struct ppi_data *ppi = DEVTOSOFTC(dev);

        destroy_dev(ppi->ppi_cdev);
#ifdef PERIPH_1284
        if (ppi->intr_resource != NULL) {
                bus_teardown_intr(dev, ppi->intr_resource, ppi->intr_cookie);
                bus_release_resource(dev, SYS_RES_IRQ, 0, ppi->intr_resource);
        }
#endif
        sx_destroy(&ppi->ppi_lock);
        return (0);
}

#ifdef PERIPH_1284
/*
 * Cable
 * -----
 *
 * Use an IEEE1284 compliant (DB25/DB25) cable with the following tricks:
 *
 * nStrobe   <-> nAck           1  <-> 10
 * nAutofd   <-> Busy           11 <-> 14
 * nSelectin <-> Select         17 <-> 13
 * nInit     <-> nFault         15 <-> 16
 *
 */
static void
ppiintr(void *arg)
{
        device_t ppidev = (device_t)arg;
        device_t ppbus = device_get_parent(ppidev);
        struct ppi_data *ppi = DEVTOSOFTC(ppidev);

        ppb_assert_locked(ppbus);
        ppi_disable_intr(ppidev);

        switch (ppb_1284_get_state(ppbus)) {
        /* accept IEEE1284 negotiation then wakeup a waiting process to
         * continue negotiation at process level */
        case PPB_FORWARD_IDLE:
                /* Event 1 */
                if ((ppb_rstr(ppbus) & (SELECT | nBUSY)) ==
                                                        (SELECT | nBUSY)) {
                        /* IEEE1284 negotiation */
#ifdef DEBUG_1284
                        printf("N");
#endif

                        /* Event 2 - prepare for reading the ext. value */
                        ppb_wctr(ppbus, (PCD | STROBE | nINIT) & ~SELECTIN);

                        ppb_1284_set_state(ppbus, PPB_NEGOCIATION);

                } else {
#ifdef DEBUG_1284
                        printf("0x%x", ppb_rstr(ppbus));
#endif
                        ppb_peripheral_terminate(ppbus, PPB_DONTWAIT);
                        break;
                }

                /* wake up any process waiting for negotiation from
                 * remote master host */

                /* XXX should set a variable to warn the process about
                 * the interrupt */

                wakeup(ppi);
                break;
        default:
#ifdef DEBUG_1284
                printf("?%d", ppb_1284_get_state(ppbus));
#endif
                ppb_1284_set_state(ppbus, PPB_FORWARD_IDLE);
                ppb_set_mode(ppbus, PPB_COMPATIBLE);
                break;
        }

        ppi_enable_intr(ppidev);

        return;
}
#endif /* PERIPH_1284 */

static int
ppiopen(struct cdev *dev, int flags, int fmt, struct thread *td)
{
        struct ppi_data *ppi = dev->si_drv1;
        device_t ppidev = ppi->ppi_device;
        device_t ppbus = device_get_parent(ppidev);
        int res;

        sx_xlock(&ppi->ppi_lock);
        if (!(ppi->ppi_flags & HAVE_PPBUS)) {
                ppb_lock(ppbus);
                res = ppb_request_bus(ppbus, ppidev,
                    (flags & O_NONBLOCK) ? PPB_DONTWAIT : PPB_WAIT | PPB_INTR);
                ppb_unlock(ppbus);
                if (res) {
                        sx_xunlock(&ppi->ppi_lock);
                        return (res);
                }

                ppi->ppi_flags |= HAVE_PPBUS;
        }
        sx_xunlock(&ppi->ppi_lock);

        return (0);
}

static int
ppiclose(struct cdev *dev, int flags, int fmt, struct thread *td)
{
        struct ppi_data *ppi = dev->si_drv1;
        device_t ppidev = ppi->ppi_device;
        device_t ppbus = device_get_parent(ppidev);

        sx_xlock(&ppi->ppi_lock);
        ppb_lock(ppbus);
#ifdef PERIPH_1284
        switch (ppb_1284_get_state(ppbus)) {
        case PPB_PERIPHERAL_IDLE:
                ppb_peripheral_terminate(ppbus, 0);
                break;
        case PPB_REVERSE_IDLE:
        case PPB_EPP_IDLE:
        case PPB_ECP_FORWARD_IDLE:
        default:
                ppb_1284_terminate(ppbus);
                break;
        }
#endif /* PERIPH_1284 */

        /* unregistration of interrupt forced by release */
        ppb_release_bus(ppbus, ppidev);
        ppb_unlock(ppbus);

        ppi->ppi_flags &= ~HAVE_PPBUS;
        sx_xunlock(&ppi->ppi_lock);

        return (0);
}

/*
 * ppiread()
 *
 * IEEE1284 compliant read.
 *
 * First, try negotiation to BYTE then NIBBLE mode
 * If no data is available, wait for it otherwise transfer as much as possible
 */
static int
ppiread(struct cdev *dev, struct uio *uio, int ioflag)
{
#ifdef PERIPH_1284
        struct ppi_data *ppi = dev->si_drv1;
        device_t ppidev = ppi->ppi_device;
        device_t ppbus = device_get_parent(ppidev);
        int len, error = 0;
        char *buffer;

        buffer = malloc(BUFSIZE, M_DEVBUF, M_WAITOK);

        ppb_lock(ppbus);
        switch (ppb_1284_get_state(ppbus)) {
        case PPB_PERIPHERAL_IDLE:
                ppb_peripheral_terminate(ppbus, 0);
                /* FALLTHROUGH */

        case PPB_FORWARD_IDLE:
                /* if can't negotiate NIBBLE mode then try BYTE mode,
                 * the peripheral may be a computer
                 */
                if ((ppb_1284_negociate(ppbus,
                        ppi->ppi_mode = PPB_NIBBLE, 0))) {
                        /* XXX Wait 2 seconds to let the remote host some
                         * time to terminate its interrupt
                         */
                        ppb_sleep(ppbus, ppi, PPBPRI, "ppiread", 2 * hz);

                        if ((error = ppb_1284_negociate(ppbus,
                            ppi->ppi_mode = PPB_BYTE, 0))) {
                                ppb_unlock(ppbus);
                                free(buffer, M_DEVBUF);
                                return (error);
                        }
                }
                break;

        case PPB_REVERSE_IDLE:
        case PPB_EPP_IDLE:
        case PPB_ECP_FORWARD_IDLE:
        default:
                break;
        }

#ifdef DEBUG_1284
        printf("N");
#endif
        /* read data */
        len = 0;
        while (uio->uio_resid) {
                error = ppb_1284_read(ppbus, ppi->ppi_mode,
                    buffer, min(BUFSIZE, uio->uio_resid), &len);
                ppb_unlock(ppbus);
                if (error)
                        goto error;

                if (!len)
                        goto error;             /* no more data */

#ifdef DEBUG_1284
                printf("d");
#endif
                if ((error = uiomove(buffer, len, uio)))
                        goto error;
                ppb_lock(ppbus);
        }
        ppb_unlock(ppbus);

error:
        free(buffer, M_DEVBUF);
#else /* PERIPH_1284 */
        int error = ENODEV;
#endif

        return (error);
}

/*
 * ppiwrite()
 *
 * IEEE1284 compliant write
 *
 * Actually, this is the peripheral side of a remote IEEE1284 read
 *
 * The first part of the negotiation (IEEE1284 device detection) is
 * done at interrupt level, then the remaining is done by the writing
 * process
 *
 * Once negotiation done, transfer data
 */
static int
ppiwrite(struct cdev *dev, struct uio *uio, int ioflag)
{
#ifdef PERIPH_1284
        struct ppi_data *ppi = dev->si_drv1;
        device_t ppidev = ppi->ppi_device;
        device_t ppbus = device_get_parent(ppidev);
        int len, error = 0, sent;
        char *buffer;

#if 0
        int ret;

        #define ADDRESS         MS_PARAM(0, 0, MS_TYP_PTR)
        #define LENGTH          MS_PARAM(0, 1, MS_TYP_INT)

        struct ppb_microseq msq[] = {
                  { MS_OP_PUT, { MS_UNKNOWN, MS_UNKNOWN, MS_UNKNOWN } },
                  MS_RET(0)
        };

        buffer = malloc(BUFSIZE, M_DEVBUF, M_WAITOK);
        ppb_lock(ppbus);

        /* negotiate ECP mode */
        if (ppb_1284_negociate(ppbus, PPB_ECP, 0)) {
                printf("ppiwrite: ECP negotiation failed\n");
        }

        while (!error && (len = min(uio->uio_resid, BUFSIZE))) {
                ppb_unlock(ppbus);
                uiomove(buffer, len, uio);

                ppb_MS_init_msq(msq, 2, ADDRESS, buffer, LENGTH, len);

                ppb_lock(ppbus);
                error = ppb_MS_microseq(ppbus, msq, &ret);
        }
#else
        buffer = malloc(BUFSIZE, M_DEVBUF, M_WAITOK);
        ppb_lock(ppbus);
#endif

        /* we have to be peripheral to be able to send data, so
         * wait for the appropriate state
         */
        if (ppb_1284_get_state(ppbus) < PPB_PERIPHERAL_NEGOCIATION)
                ppb_1284_terminate(ppbus);

        while (ppb_1284_get_state(ppbus) != PPB_PERIPHERAL_IDLE) {
                /* XXX should check a variable before sleeping */
#ifdef DEBUG_1284
                printf("s");
#endif

                ppi_enable_intr(ppidev);

                /* sleep until IEEE1284 negotiation starts */
                error = ppb_sleep(ppbus, ppi, PCATCH | PPBPRI, "ppiwrite", 0);

                switch (error) {
                case 0:
                        /* negotiate peripheral side with BYTE mode */
                        ppb_peripheral_negociate(ppbus, PPB_BYTE, 0);
                        break;
                case EWOULDBLOCK:
                        break;
                default:
                        goto error;
                }
        }
#ifdef DEBUG_1284
        printf("N");
#endif

        /* negotiation done, write bytes to master host */
        while ((len = min(uio->uio_resid, BUFSIZE)) != 0) {
                ppb_unlock(ppbus);
                uiomove(buffer, len, uio);
                ppb_lock(ppbus);
                if ((error = byte_peripheral_write(ppbus,
                                                buffer, len, &sent)))
                        goto error;
#ifdef DEBUG_1284
                printf("d");
#endif
        }

error:
        ppb_unlock(ppbus);
        free(buffer, M_DEVBUF);
#else /* PERIPH_1284 */
        int error = ENODEV;
#endif

        return (error);
}

static int
ppiioctl(struct cdev *dev, u_long cmd, caddr_t data, int flags, struct thread *td)
{
        struct ppi_data *ppi = dev->si_drv1;
        device_t ppidev = ppi->ppi_device;
        device_t ppbus = device_get_parent(ppidev);
        int error = 0;
        u_int8_t *val = (u_int8_t *)data;

        ppb_lock(ppbus);
        switch (cmd) {
        case PPIGDATA:                  /* get data register */
                *val = ppb_rdtr(ppbus);
                break;
        case PPIGSTATUS:                /* get status bits */
                *val = ppb_rstr(ppbus);
                break;
        case PPIGCTRL:                  /* get control bits */
                *val = ppb_rctr(ppbus);
                break;
        case PPIGEPPD:                  /* get EPP data bits */
                *val = ppb_repp_D(ppbus);
                break;
        case PPIGECR:                   /* get ECP bits */
                *val = ppb_recr(ppbus);
                break;
        case PPIGFIFO:                  /* read FIFO */
                *val = ppb_rfifo(ppbus);
                break;
        case PPISDATA:                  /* set data register */
                ppb_wdtr(ppbus, *val);
                break;
        case PPISSTATUS:                /* set status bits */
                ppb_wstr(ppbus, *val);
                break;
        case PPISCTRL:                  /* set control bits */
                ppb_wctr(ppbus, *val);
                break;
        case PPISEPPD:                  /* set EPP data bits */
                ppb_wepp_D(ppbus, *val);
                break;
        case PPISECR:                   /* set ECP bits */
                ppb_wecr(ppbus, *val);
                break;
        case PPISFIFO:                  /* write FIFO */
                ppb_wfifo(ppbus, *val);
                break;
        case PPIGEPPA:                  /* get EPP address bits */
                *val = ppb_repp_A(ppbus);
                break;
        case PPISEPPA:                  /* set EPP address bits */
                ppb_wepp_A(ppbus, *val);
                break;
        default:
                error = ENOTTY;
                break;
        }
        ppb_unlock(ppbus);

        return (error);
}

static device_method_t ppi_methods[] = {
        /* device interface */
        DEVMETHOD(device_identify,      ppi_identify),
        DEVMETHOD(device_probe,         ppi_probe),
        DEVMETHOD(device_attach,        ppi_attach),
        DEVMETHOD(device_detach,        ppi_detach),
        DEVMETHOD_END
};

static driver_t ppi_driver = {
        "ppi",
        ppi_methods,
        sizeof(struct ppi_data),
};

DRIVER_MODULE(ppi, ppbus, ppi_driver, 0, 0);
MODULE_DEPEND(ppi, ppbus, 1, 1, 1);