/*      $OpenBSD: ch.c,v 1.72 2023/04/11 00:45:09 jsg Exp $     */
/*      $NetBSD: ch.c,v 1.26 1997/02/21 22:06:52 thorpej Exp $  */

/*
 * Copyright (c) 1996, 1997 Jason R. Thorpe <thorpej@and.com>
 * All rights reserved.
 *
 * Partially based on an autochanger driver written by Stefan Grefen
 * and on an autochanger driver written by the Systems Programming Group
 * at the University of Utah Computer Science Department.
 *
 * 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 acknowledgements:
 *      This product includes software developed by Jason R. Thorpe
 *      for And Communications, http://www.and.com/
 * 4. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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/param.h>
#include <sys/systm.h>
#include <sys/errno.h>
#include <sys/ioctl.h>
#include <sys/chio.h>
#include <sys/device.h>
#include <sys/malloc.h>
#include <sys/pool.h>
#include <sys/conf.h>
#include <sys/fcntl.h>

#include <scsi/scsi_all.h>
#include <scsi/scsi_changer.h>
#include <scsi/scsi_debug.h>
#include <scsi/scsiconf.h>

#define CHRETRIES       2
#define CHUNIT(x)       (minor((x)))

struct ch_softc {
        struct device            sc_dev;        /* generic device info */
        struct scsi_link        *sc_link;       /* link in the SCSI bus */

        int                      sc_picker;     /* current picker */

        /*
         * The following information is obtained from the
         * element address assignment page.
         */
        int                      sc_firsts[4];  /* firsts, indexed by CHET_* */
        int                      sc_counts[4];  /* counts, indexed by CHET_* */

        /*
         * The following mask defines the legal combinations
         * of elements for the MOVE MEDIUM command.
         */
        u_int8_t                 sc_movemask[4];

        /*
         * As above, but for EXCHANGE MEDIUM.
         */
        u_int8_t                 sc_exchangemask[4];

        int                      flags;         /* misc. info */

        /*
         * Quirks; see below.
         */
        int                      sc_settledelay; /* delay for settle */

};

/* sc_flags */
#define CHF_ROTATE      0x01            /* picker can rotate */

/* Autoconfiguration glue */
int     chmatch(struct device *, void *, void *);
void    chattach(struct device *, struct device *, void *);

const struct cfattach ch_ca = {
        sizeof(struct ch_softc), chmatch, chattach
};

struct cfdriver ch_cd = {
        NULL, "ch", DV_DULL
};

const struct scsi_inquiry_pattern ch_patterns[] = {
        {T_CHANGER, T_REMOV,
         "",            "",             ""},
};

int     ch_move(struct ch_softc *, struct changer_move *);
int     ch_exchange(struct ch_softc *, struct changer_exchange *);
int     ch_position(struct ch_softc *, struct changer_position *);
int     ch_usergetelemstatus(struct ch_softc *,
            struct changer_element_status_request *);
int     ch_getelemstatus(struct ch_softc *, int, int, caddr_t, size_t, int);
int     ch_get_params(struct ch_softc *, int);
int     ch_interpret_sense(struct scsi_xfer *xs);
void    ch_get_quirks(struct ch_softc *, struct scsi_inquiry_data *);

/*
 * SCSI changer quirks.
 */
struct chquirk {
        struct  scsi_inquiry_pattern cq_match; /* device id pattern */
        int     cq_settledelay; /* settle delay, in seconds */
};

struct chquirk chquirks[] = {
        {{T_CHANGER, T_REMOV,
          "SPECTRA",    "9000",         "0200"},
         75},
};

int
chmatch(struct device *parent, void *match, void *aux)
{
        struct scsi_attach_args         *sa = aux;
        struct scsi_inquiry_data        *inq = &sa->sa_sc_link->inqdata;
        int                              priority;

        (void)scsi_inqmatch(inq, ch_patterns, nitems(ch_patterns),
            sizeof(ch_patterns[0]), &priority);

        return priority;
}

void
chattach(struct device *parent, struct device *self, void *aux)
{
        struct ch_softc                 *sc = (struct ch_softc *)self;
        struct scsi_attach_args         *sa = aux;
        struct scsi_link                *link = sa->sa_sc_link;

        /* Glue into the SCSI bus */
        sc->sc_link = link;
        link->interpret_sense = ch_interpret_sense;
        link->device_softc = sc;
        link->openings = 1;

        printf("\n");

        /*
         * Store our device's quirks.
         */
        ch_get_quirks(sc, &link->inqdata);
}

int
chopen(dev_t dev, int flags, int fmt, struct proc *p)
{
        struct ch_softc         *sc;
        int                      oldcounts[4];
        int                      i, unit, error = 0;

        unit = CHUNIT(dev);
        if ((unit >= ch_cd.cd_ndevs) ||
            ((sc = ch_cd.cd_devs[unit]) == NULL))
                return ENXIO;

        /*
         * Only allow one open at a time.
         */
        if (ISSET(sc->sc_link->flags, SDEV_OPEN))
                return EBUSY;

        SET(sc->sc_link->flags, SDEV_OPEN);

        /*
         * Absorb any unit attention errors. We must notice
         * "Not ready" errors as a changer will report "In the
         * process of getting ready" any time it must rescan
         * itself to determine the state of the changer.
         */
        error = scsi_test_unit_ready(sc->sc_link, TEST_READY_RETRIES,
            SCSI_IGNORE_ILLEGAL_REQUEST | SCSI_IGNORE_MEDIA_CHANGE);
        if (error)
                goto bad;

        /*
         * Get information about the device. Save old information
         * so we can decide whether to be verbose about new parameters.
         */
        for (i = 0; i < 4; i++) {
                oldcounts[i] = sc->sc_counts[i];
        }
        error = ch_get_params(sc, scsi_autoconf);
        if (error)
                goto bad;

        for (i = 0; i < 4; i++) {
                if (oldcounts[i] != sc->sc_counts[i]) {
                        break;
                }
        }
        if (i < 4) {
#ifdef CHANGER_DEBUG
#define PLURAL(c)       (c) == 1 ? "" : "s"
                printf("%s: %d slot%s, %d drive%s, %d picker%s, %d portal%s\n",
                    sc->sc_dev.dv_xname,
                    sc->sc_counts[CHET_ST], PLURAL(sc->sc_counts[CHET_ST]),
                    sc->sc_counts[CHET_DT], PLURAL(sc->sc_counts[CHET_DT]),
                    sc->sc_counts[CHET_MT], PLURAL(sc->sc_counts[CHET_MT]),
                    sc->sc_counts[CHET_IE], PLURAL(sc->sc_counts[CHET_IE]));
#undef PLURAL
                printf("%s: move mask: 0x%x 0x%x 0x%x 0x%x\n",
                    sc->sc_dev.dv_xname,
                    sc->sc_movemask[CHET_MT], sc->sc_movemask[CHET_ST],
                    sc->sc_movemask[CHET_IE], sc->sc_movemask[CHET_DT]);
                printf("%s: exchange mask: 0x%x 0x%x 0x%x 0x%x\n",
                    sc->sc_dev.dv_xname,
                    sc->sc_exchangemask[CHET_MT], sc->sc_exchangemask[CHET_ST],
                    sc->sc_exchangemask[CHET_IE], sc->sc_exchangemask[CHET_DT]);
#endif /* CHANGER_DEBUG */
        }

        /* Default the current picker. */
        sc->sc_picker = sc->sc_firsts[CHET_MT];

        return 0;

bad:
        CLR(sc->sc_link->flags, SDEV_OPEN);
        return error;
}

int
chclose(dev_t dev, int flags, int fmt, struct proc *p)
{
        struct ch_softc *sc = ch_cd.cd_devs[CHUNIT(dev)];

        CLR(sc->sc_link->flags, SDEV_OPEN);
        return 0;
}

int
chioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct proc *p)
{
        struct ch_softc         *sc = ch_cd.cd_devs[CHUNIT(dev)];
        int                      error = 0;

        /*
         * If this command can change the device's state, we must
         * have the device open for writing.
         */
        switch (cmd) {
        case CHIOGPICKER:
        case CHIOGPARAMS:
        case CHIOGSTATUS:
                break;

        default:
                if (!ISSET(flags, FWRITE))
                        return EBADF;
        }

        switch (cmd) {
        case CHIOMOVE:
                error = ch_move(sc, (struct changer_move *)data);
                break;

        case CHIOEXCHANGE:
                error = ch_exchange(sc, (struct changer_exchange *)data);
                break;

        case CHIOPOSITION:
                error = ch_position(sc, (struct changer_position *)data);
                break;

        case CHIOGPICKER:
                *(int *)data = sc->sc_picker - sc->sc_firsts[CHET_MT];
                break;

        case CHIOSPICKER:       {
                int new_picker = *(int *)data;

                if (new_picker > (sc->sc_counts[CHET_MT] - 1))
                        return EINVAL;
                sc->sc_picker = sc->sc_firsts[CHET_MT] + new_picker;
                break;          }

        case CHIOGPARAMS:       {
                struct changer_params *cp = (struct changer_params *)data;

                cp->cp_curpicker = sc->sc_picker - sc->sc_firsts[CHET_MT];
                cp->cp_npickers = sc->sc_counts[CHET_MT];
                cp->cp_nslots = sc->sc_counts[CHET_ST];
                cp->cp_nportals = sc->sc_counts[CHET_IE];
                cp->cp_ndrives = sc->sc_counts[CHET_DT];
                break;          }

        case CHIOGSTATUS:       {
                struct changer_element_status_request *cesr =
                    (struct changer_element_status_request *)data;

                error = ch_usergetelemstatus(sc, cesr);
                break;          }

        /* Implement prevent/allow? */

        default:
                error = scsi_do_ioctl(sc->sc_link, cmd, data, flags);
                break;
        }

        return error;
}

int
ch_move(struct ch_softc *sc, struct changer_move *cm)
{
        struct scsi_move_medium         *cmd;
        struct scsi_xfer                *xs;
        int                              error;
        u_int16_t                        fromelem, toelem;

        /*
         * Check arguments.
         */
        if ((cm->cm_fromtype > CHET_DT) || (cm->cm_totype > CHET_DT))
                return EINVAL;
        if ((cm->cm_fromunit > (sc->sc_counts[cm->cm_fromtype] - 1)) ||
            (cm->cm_tounit > (sc->sc_counts[cm->cm_totype] - 1)))
                return ENODEV;

        /*
         * Check the request against the changer's capabilities.
         */
        if ((sc->sc_movemask[cm->cm_fromtype] & (1 << cm->cm_totype)) == 0)
                return EINVAL;

        /*
         * Calculate the source and destination elements.
         */
        fromelem = sc->sc_firsts[cm->cm_fromtype] + cm->cm_fromunit;
        toelem = sc->sc_firsts[cm->cm_totype] + cm->cm_tounit;

        /*
         * Build the SCSI command.
         */
        xs = scsi_xs_get(sc->sc_link, 0);
        if (xs == NULL)
                return ENOMEM;
        xs->cmdlen = sizeof(*cmd);
        xs->retries = CHRETRIES;
        xs->timeout = 100000;

        cmd = (struct scsi_move_medium *)&xs->cmd;
        cmd->opcode = MOVE_MEDIUM;
        _lto2b(sc->sc_picker, cmd->tea);
        _lto2b(fromelem, cmd->src);
        _lto2b(toelem, cmd->dst);
        if (ISSET(cm->cm_flags, CM_INVERT))
                SET(cmd->flags, MOVE_MEDIUM_INVERT);

        error = scsi_xs_sync(xs);
        scsi_xs_put(xs);

        return error;
}

int
ch_exchange(struct ch_softc *sc, struct changer_exchange *ce)
{
        struct scsi_exchange_medium     *cmd;
        struct scsi_xfer                *xs;
        int                              error;
        u_int16_t                        src, dst1, dst2;

        /*
         * Check arguments.
         */
        if ((ce->ce_srctype > CHET_DT) || (ce->ce_fdsttype > CHET_DT) ||
            (ce->ce_sdsttype > CHET_DT))
                return EINVAL;
        if ((ce->ce_srcunit > (sc->sc_counts[ce->ce_srctype] - 1)) ||
            (ce->ce_fdstunit > (sc->sc_counts[ce->ce_fdsttype] - 1)) ||
            (ce->ce_sdstunit > (sc->sc_counts[ce->ce_sdsttype] - 1)))
                return ENODEV;

        /*
         * Check the request against the changer's capabilities.
         */
        if (((sc->sc_exchangemask[ce->ce_srctype] &
            (1 << ce->ce_fdsttype)) == 0) ||
            ((sc->sc_exchangemask[ce->ce_fdsttype] &
            (1 << ce->ce_sdsttype)) == 0))
                return EINVAL;

        /*
         * Calculate the source and destination elements.
         */
        src = sc->sc_firsts[ce->ce_srctype] + ce->ce_srcunit;
        dst1 = sc->sc_firsts[ce->ce_fdsttype] + ce->ce_fdstunit;
        dst2 = sc->sc_firsts[ce->ce_sdsttype] + ce->ce_sdstunit;

        /*
         * Build the SCSI command.
         */
        xs = scsi_xs_get(sc->sc_link, 0);
        if (xs == NULL)
                return ENOMEM;
        xs->cmdlen = sizeof(*cmd);
        xs->retries = CHRETRIES;
        xs->timeout = 100000;

        cmd = (struct scsi_exchange_medium *)&xs->cmd;
        cmd->opcode = EXCHANGE_MEDIUM;
        _lto2b(sc->sc_picker, cmd->tea);
        _lto2b(src, cmd->src);
        _lto2b(dst1, cmd->fdst);
        _lto2b(dst2, cmd->sdst);
        if (ISSET(ce->ce_flags, CE_INVERT1))
                SET(cmd->flags, EXCHANGE_MEDIUM_INV1);
        if (ISSET(ce->ce_flags, CE_INVERT2))
                SET(cmd->flags, EXCHANGE_MEDIUM_INV2);

        error = scsi_xs_sync(xs);
        scsi_xs_put(xs);

        return error;
}

int
ch_position(struct ch_softc *sc, struct changer_position *cp)
{
        struct scsi_position_to_element         *cmd;
        struct scsi_xfer                        *xs;
        int                                      error;
        u_int16_t                                dst;

        /*
         * Check arguments.
         */
        if (cp->cp_type > CHET_DT)
                return EINVAL;
        if (cp->cp_unit > (sc->sc_counts[cp->cp_type] - 1))
                return ENODEV;

        /*
         * Calculate the destination element.
         */
        dst = sc->sc_firsts[cp->cp_type] + cp->cp_unit;

        /*
         * Build the SCSI command.
         */
        xs = scsi_xs_get(sc->sc_link, 0);
        if (xs == NULL)
                return ENOMEM;
        xs->cmdlen = sizeof(*cmd);
        xs->retries = CHRETRIES;
        xs->timeout = 100000;

        cmd = (struct scsi_position_to_element *)&xs->cmd;
        cmd->opcode = POSITION_TO_ELEMENT;
        _lto2b(sc->sc_picker, cmd->tea);
        _lto2b(dst, cmd->dst);
        if (ISSET(cp->cp_flags, CP_INVERT))
                SET(cmd->flags, POSITION_TO_ELEMENT_INVERT);

        error = scsi_xs_sync(xs);
        scsi_xs_put(xs);

        return error;
}

/*
 * Copy a volume tag to a volume_tag struct, converting SCSI byte order
 * to host native byte order in the volume serial number.  The volume
 * label as returned by the changer is transferred to user mode as
 * nul-terminated string.  Volume labels are truncated at the first
 * space, as suggested by SCSI-2.
 */
static  void
copy_voltag(struct changer_voltag *uvoltag, struct volume_tag *voltag)
{
        int i;

        for (i=0; i<CH_VOLTAG_MAXLEN; i++) {
                char c = voltag->vif[i];
                if (c && c != ' ')
                        uvoltag->cv_volid[i] = c;
                else
                        break;
        }
        uvoltag->cv_volid[i] = '\0';
        uvoltag->cv_serial = _2btol(voltag->vsn);
}

/*
 * Copy an element status descriptor to a user-mode
 * changer_element_status structure.
 */
static void
copy_element_status(struct ch_softc *sc, int flags,
    struct read_element_status_descriptor *desc,
    struct changer_element_status *ces)
{
        u_int16_t eaddr = _2btol(desc->eaddr);
        u_int16_t et;

        for (et = CHET_MT; et <= CHET_DT; et++) {
                if ((sc->sc_firsts[et] <= eaddr)
                    && ((sc->sc_firsts[et] + sc->sc_counts[et])
                    > eaddr)) {
                        ces->ces_addr = eaddr - sc->sc_firsts[et];
                        ces->ces_type = et;
                        break;
                }
        }

        ces->ces_flags = desc->flags1;

        ces->ces_sensecode = desc->sense_code;
        ces->ces_sensequal = desc->sense_qual;

        if (desc->flags2 & READ_ELEMENT_STATUS_INVERT)
                ces->ces_flags |= READ_ELEMENT_STATUS_EXCEPT;

        if (desc->flags2 & READ_ELEMENT_STATUS_SVALID) {
                eaddr = _2btol(desc->ssea);

                /* convert source address to logical format */
                for (et = CHET_MT; et <= CHET_DT; et++) {
                        if ((sc->sc_firsts[et] <= eaddr)
                            && ((sc->sc_firsts[et] + sc->sc_counts[et])
                                > eaddr)) {
                                ces->ces_source_addr =
                                        eaddr - sc->sc_firsts[et];
                                ces->ces_source_type = et;
                                ces->ces_flags |= READ_ELEMENT_STATUS_ACCESS;
                                break;
                        }
                }

                if (!(ces->ces_flags & READ_ELEMENT_STATUS_ACCESS))
                        printf("ch: warning: could not map element source "
                               "address %ud to a valid element type\n",
                               eaddr);
        }

        if (ISSET(flags, READ_ELEMENT_STATUS_PVOLTAG))
                copy_voltag(&ces->ces_pvoltag, &desc->pvoltag);
        if (ISSET(flags, READ_ELEMENT_STATUS_AVOLTAG))
                copy_voltag(&ces->ces_avoltag, &desc->avoltag);
}

/*
 * Perform a READ ELEMENT STATUS on behalf of the user, and return to
 * the user only the data the user is interested in (i.e. an array of
 * changer_element_status structures)
 */
int
ch_usergetelemstatus(struct ch_softc *sc,
    struct changer_element_status_request *cesr)
{
        struct changer_element_status           *user_data = NULL;
        struct read_element_status_header       *st_hdr;
        struct read_element_status_page_header  *pg_hdr;
        caddr_t                                  desc;
        caddr_t                                  data = NULL;
        size_t                                   size, desclen, udsize;
        int                                      avail, chet, i, want_voltags;
        int                                      error = 0;

        chet = cesr->cesr_type;
        want_voltags = (cesr->cesr_flags & CESR_VOLTAGS) ? 1 : 0;

        /*
         * If there are no elements of the requested type in the changer,
         * the request is invalid.
         */
        if (sc->sc_counts[chet] == 0)
                return EINVAL;

        /*
         * Request one descriptor for the given element type.  This
         * is used to determine the size of the descriptor so that
         * we can allocate enough storage for all of them.  We assume
         * that the first one can fit into 1k.
         */
        size = 1024;
        data = dma_alloc(size, PR_WAITOK);
        error = ch_getelemstatus(sc, sc->sc_firsts[chet], 1, data, size,
            want_voltags);
        if (error)
                goto done;

        st_hdr = (struct read_element_status_header *)data;
        pg_hdr = (struct read_element_status_page_header *) (st_hdr + 1);
        desclen = _2btol(pg_hdr->edl);

        dma_free(data, size);

        /*
         * Reallocate storage for descriptors and get them from the
         * device.
         */
        size = sizeof(struct read_element_status_header) +
            sizeof(struct read_element_status_page_header) +
            (desclen * sc->sc_counts[chet]);
        data = dma_alloc(size, PR_WAITOK);
        error = ch_getelemstatus(sc, sc->sc_firsts[chet],
            sc->sc_counts[chet], data, size, want_voltags);
        if (error)
                goto done;

        /*
         * Fill in the user status array.
         */
        st_hdr = (struct read_element_status_header *)data;
        pg_hdr = (struct read_element_status_page_header *) (st_hdr + 1);

        avail = _2btol(st_hdr->count);
        if (avail != sc->sc_counts[chet]) {
                error = EINVAL;
                goto done;
        }

        user_data = mallocarray(avail, sizeof(struct changer_element_status),
            M_DEVBUF, M_WAITOK | M_ZERO);
        udsize = avail * sizeof(struct changer_element_status);

        desc = (caddr_t)(pg_hdr + 1);
        for (i = 0; i < avail; ++i) {
                struct changer_element_status *ces = &(user_data[i]);
                copy_element_status(sc, pg_hdr->flags,
                    (struct read_element_status_descriptor *)desc, ces);
                desc += desclen;
        }

        /* Copy array out to userspace. */
        error = copyout(user_data, cesr->cesr_data, udsize);

done:
        if (data != NULL)
                dma_free(data, size);
        if (user_data != NULL)
                free(user_data, M_DEVBUF, udsize);
        return error;
}

int
ch_getelemstatus(struct ch_softc *sc, int first, int count, caddr_t data,
    size_t datalen, int voltag)
{
        struct scsi_read_element_status         *cmd;
        struct scsi_xfer                        *xs;
        int                                      error;

        /*
         * Build SCSI command.
         */
        xs = scsi_xs_get(sc->sc_link, SCSI_DATA_IN);
        if (xs == NULL)
                return ENOMEM;
        xs->cmdlen = sizeof(*cmd);
        xs->data = data;
        xs->datalen = datalen;
        xs->retries = CHRETRIES;
        xs->timeout = 100000;

        cmd = (struct scsi_read_element_status *)&xs->cmd;
        cmd->opcode = READ_ELEMENT_STATUS;
        _lto2b(first, cmd->sea);
        _lto2b(count, cmd->count);
        _lto3b(datalen, cmd->len);
        if (voltag)
                SET(cmd->byte2, READ_ELEMENT_STATUS_VOLTAG);

        error = scsi_xs_sync(xs);
        scsi_xs_put(xs);

        return error;
}

/*
 * Ask the device about itself and fill in the parameters in our
 * softc.
 */
int
ch_get_params(struct ch_softc *sc, int flags)
{
        union scsi_mode_sense_buf                       *data;
        struct page_element_address_assignment          *ea;
        struct page_device_capabilities                 *cap;
        u_int8_t                                        *moves, *exchanges;
        int                                              big, error, from;

        data = dma_alloc(sizeof(*data), PR_NOWAIT);
        if (data == NULL)
                return ENOMEM;

        /*
         * Grab info from the element address assignment page (0x1d).
         */
        error = scsi_do_mode_sense(sc->sc_link, EA_PAGE, data,
            (void **)&ea, sizeof(*ea), flags, &big);
        if (error == 0 && ea == NULL)
                error = EIO;
        if (error != 0) {
#ifdef CHANGER_DEBUG
                printf("%s: could not sense element address page\n",
                    sc->sc_dev.dv_xname);
#endif /* CHANGER_DEBUG */
                dma_free(data, sizeof(*data));
                return error;
        }

        sc->sc_firsts[CHET_MT] = _2btol(ea->mtea);
        sc->sc_counts[CHET_MT] = _2btol(ea->nmte);
        sc->sc_firsts[CHET_ST] = _2btol(ea->fsea);
        sc->sc_counts[CHET_ST] = _2btol(ea->nse);
        sc->sc_firsts[CHET_IE] = _2btol(ea->fieea);
        sc->sc_counts[CHET_IE] = _2btol(ea->niee);
        sc->sc_firsts[CHET_DT] = _2btol(ea->fdtea);
        sc->sc_counts[CHET_DT] = _2btol(ea->ndte);

        /* XXX Ask for transport geometry page. */

        /*
         * Grab info from the capabilities page (0x1f).
         */
        error = scsi_do_mode_sense(sc->sc_link, CAP_PAGE, data,
            (void **)&cap, sizeof(*cap), flags, &big);
        if (error == 0 && cap == NULL)
                error = EIO;
        if (error != 0) {
#ifdef CHANGER_DEBUG
                printf("%s: could not sense capabilities page\n",
                    sc->sc_dev.dv_xname);
#endif /* CHANGER_DEBUG */
                dma_free(data, sizeof(*data));
                return error;
        }

        bzero(sc->sc_movemask, sizeof(sc->sc_movemask));
        bzero(sc->sc_exchangemask, sizeof(sc->sc_exchangemask));
        moves = &cap->move_from_mt;
        exchanges = &cap->exchange_with_mt;
        for (from = CHET_MT; from <= CHET_DT; ++from) {
                sc->sc_movemask[from] = moves[from];
                sc->sc_exchangemask[from] = exchanges[from];
        }

        SET(sc->sc_link->flags, SDEV_MEDIA_LOADED);
        dma_free(data, sizeof(*data));
        return 0;
}

void
ch_get_quirks(struct ch_softc *sc, struct scsi_inquiry_data *inqbuf)
{
        const struct chquirk            *match;
        int                              priority;

        sc->sc_settledelay = 0;

        match = (const struct chquirk *)scsi_inqmatch(inqbuf,
            (caddr_t)chquirks,
            sizeof(chquirks) / sizeof(chquirks[0]),
            sizeof(chquirks[0]), &priority);
        if (priority != 0) {
                sc->sc_settledelay = match->cq_settledelay;
        }
}

/*
 * Look at the returned sense and act on the error to determine
 * the unix error number to pass back... (0 = report no error)
 *                            (-1 = continue processing)
 */
int
ch_interpret_sense(struct scsi_xfer *xs)
{
        struct scsi_sense_data          *sense = &xs->sense;
        struct scsi_link                *link = xs->sc_link;
        u_int8_t                         serr, skey;

        serr = sense->error_code & SSD_ERRCODE;
        skey = sense->flags & SSD_KEY;

        if (!ISSET(link->flags, SDEV_OPEN) ||
            (serr != SSD_ERRCODE_CURRENT && serr != SSD_ERRCODE_DEFERRED))
                return scsi_interpret_sense(xs);

        switch (skey) {

        /*
         * We do custom processing in ch for the unit becoming ready
         * case.  in this case we do not allow xs->retries to be
         * decremented only on the "Unit Becoming Ready" case. This is
         * because tape changers report "Unit Becoming Ready" when they
         * rescan their state (i.e. when the door got opened) and can
         * take a long time for large units. Rather than having a
         * massive timeout for all operations (which would cause other
         * problems) we allow changers to wait (but be interruptible
         * with Ctrl-C) forever as long as they are reporting that they
         * are becoming ready.  all other cases are handled as per the
         * default.
         */
        case SKEY_NOT_READY:
                if (ISSET(xs->flags, SCSI_IGNORE_NOT_READY))
                        return 0;
                switch (ASC_ASCQ(sense)) {
                case SENSE_NOT_READY_BECOMING_READY:
                        SC_DEBUG(link, SDEV_DB1, ("not ready: busy (%#x)\n",
                            sense->add_sense_code_qual));
                        /* don't count this as a retry */
                        xs->retries++;
                        return scsi_delay(xs, 1);
                default:
                        return scsi_interpret_sense(xs);
                }
        default:
                return scsi_interpret_sense(xs);
        }
}