xref: /netbsd-src/sys/dev/scsipi/ch.c (revision 4d12bfcd155352508213ace5ccc59ce930ea2974)
1 /*	$NetBSD: ch.c,v 1.88 2013/08/09 19:58:44 kardel Exp $	*/
2 
3 /*-
4  * Copyright (c) 1996, 1997, 1998, 1999, 2004 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
9  * NASA Ames Research Center.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include <sys/cdefs.h>
34 __KERNEL_RCSID(0, "$NetBSD: ch.c,v 1.88 2013/08/09 19:58:44 kardel Exp $");
35 
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/kernel.h>
39 #include <sys/errno.h>
40 #include <sys/ioctl.h>
41 #include <sys/buf.h>
42 #include <sys/proc.h>
43 #include <sys/chio.h>
44 #include <sys/device.h>
45 #include <sys/malloc.h>
46 #include <sys/conf.h>
47 #include <sys/fcntl.h>
48 #include <sys/vnode.h>
49 #include <sys/time.h>
50 #include <sys/select.h>
51 #include <sys/poll.h>
52 
53 #include <dev/scsipi/scsipi_all.h>
54 #include <dev/scsipi/scsi_all.h>
55 #include <dev/scsipi/scsi_changer.h>
56 #include <dev/scsipi/scsiconf.h>
57 
58 #define CHRETRIES	2
59 #define CHTIMEOUT	(5 * 60 * 1000)
60 
61 #define CHUNIT(x)	(minor((x)))
62 
63 struct ch_softc {
64 	device_t	sc_dev;		/* generic device info */
65 	struct scsipi_periph *sc_periph;/* our periph data */
66 
67 	u_int		sc_events;	/* event bitmask */
68 	struct selinfo	sc_selq;	/* select/poll queue for events */
69 
70 	int		sc_flags;	/* misc. info */
71 
72 	int		sc_picker;	/* current picker */
73 
74 	/*
75 	 * The following information is obtained from the
76 	 * element address assignment page.
77 	 */
78 	int		sc_firsts[4];	/* firsts, indexed by CHET_* */
79 	int		sc_counts[4];	/* counts, indexed by CHET_* */
80 
81 	/*
82 	 * The following mask defines the legal combinations
83 	 * of elements for the MOVE MEDIUM command.
84 	 */
85 	u_int8_t	sc_movemask[4];
86 
87 	/*
88 	 * As above, but for EXCHANGE MEDIUM.
89 	 */
90 	u_int8_t	sc_exchangemask[4];
91 
92 	/*
93 	 * Quirks; see below.
94 	 */
95 	int		sc_settledelay;	/* delay for settle */
96 
97 };
98 
99 /* sc_flags */
100 #define CHF_ROTATE		0x01	/* picker can rotate */
101 
102 /* Autoconfiguration glue */
103 static int	chmatch(device_t, cfdata_t, void *);
104 static void	chattach(device_t, device_t, void *);
105 
106 CFATTACH_DECL_NEW(ch, sizeof(struct ch_softc),
107     chmatch, chattach, NULL, NULL);
108 
109 extern struct cfdriver ch_cd;
110 
111 static struct scsipi_inquiry_pattern ch_patterns[] = {
112 	{T_CHANGER, T_REMOV,
113 	 "",		"",		""},
114 };
115 
116 static dev_type_open(chopen);
117 static dev_type_close(chclose);
118 static dev_type_read(chread);
119 static dev_type_ioctl(chioctl);
120 static dev_type_poll(chpoll);
121 static dev_type_kqfilter(chkqfilter);
122 
123 const struct cdevsw ch_cdevsw = {
124 	chopen, chclose, chread, nowrite, chioctl,
125 	nostop, notty, chpoll, nommap, chkqfilter, D_OTHER
126 };
127 
128 /* SCSI glue */
129 static int	ch_interpret_sense(struct scsipi_xfer *);
130 
131 static const struct scsipi_periphsw ch_switch = {
132 	ch_interpret_sense,	/* check our error handler first */
133 	NULL,			/* no queue; our commands are synchronous */
134 	NULL,			/* have no async handler */
135 	NULL,			/* nothing to be done when xfer is done */
136 };
137 
138 static int	ch_move(struct ch_softc *, struct changer_move_request *);
139 static int	ch_exchange(struct ch_softc *,
140 		    struct changer_exchange_request *);
141 static int	ch_position(struct ch_softc *,
142 		    struct changer_position_request *);
143 static int	ch_ielem(struct ch_softc *);
144 static int	ch_ousergetelemstatus(struct ch_softc *, int, u_int8_t *);
145 static int	ch_usergetelemstatus(struct ch_softc *,
146 		    struct changer_element_status_request *);
147 static int	ch_getelemstatus(struct ch_softc *, int, int, void *,
148 		    size_t, int, int);
149 static int	ch_setvoltag(struct ch_softc *,
150 		    struct changer_set_voltag_request *);
151 static int	ch_get_params(struct ch_softc *, int);
152 static void	ch_get_quirks(struct ch_softc *,
153 		    struct scsipi_inquiry_pattern *);
154 static void	ch_event(struct ch_softc *, u_int);
155 static int	ch_map_element(struct ch_softc *, u_int16_t, int *, int *);
156 
157 static void	ch_voltag_convert_in(const struct changer_volume_tag *,
158 		    struct changer_voltag *);
159 static int	ch_voltag_convert_out(const struct changer_voltag *,
160 		    struct changer_volume_tag *);
161 
162 /*
163  * SCSI changer quirks.
164  */
165 struct chquirk {
166 	struct	scsipi_inquiry_pattern cq_match; /* device id pattern */
167 	int	cq_settledelay;	/* settle delay, in seconds */
168 };
169 
170 static const struct chquirk chquirks[] = {
171 	{{T_CHANGER, T_REMOV,
172 	  "SPECTRA",	"9000",		"0200"},
173 	 75},
174 };
175 
176 static int
177 chmatch(device_t parent, cfdata_t match,
178     void *aux)
179 {
180 	struct scsipibus_attach_args *sa = aux;
181 	int priority;
182 
183 	(void)scsipi_inqmatch(&sa->sa_inqbuf,
184 	    (void *)ch_patterns, sizeof(ch_patterns) / sizeof(ch_patterns[0]),
185 	    sizeof(ch_patterns[0]), &priority);
186 
187 	return (priority);
188 }
189 
190 static void
191 chattach(device_t parent, device_t self, void *aux)
192 {
193 	struct ch_softc *sc = device_private(self);
194 	struct scsipibus_attach_args *sa = aux;
195 	struct scsipi_periph *periph = sa->sa_periph;
196 
197 	sc->sc_dev = self;
198 	selinit(&sc->sc_selq);
199 
200 	/* Glue into the SCSI bus */
201 	sc->sc_periph = periph;
202 	periph->periph_dev = sc->sc_dev;
203 	periph->periph_switch = &ch_switch;
204 
205 	printf("\n");
206 
207 	/*
208 	 * Find out our device's quirks.
209 	 */
210 	ch_get_quirks(sc, &sa->sa_inqbuf);
211 
212 	/*
213 	 * Some changers require a long time to settle out, to do
214 	 * tape inventory, for instance.
215 	 */
216 	if (sc->sc_settledelay) {
217 		printf("%s: waiting %d seconds for changer to settle...\n",
218 		    device_xname(sc->sc_dev), sc->sc_settledelay);
219 		delay(1000000 * sc->sc_settledelay);
220 	}
221 
222 	/*
223 	 * Get information about the device.  Note we can't use
224 	 * interrupts yet.
225 	 */
226 	if (ch_get_params(sc, XS_CTL_DISCOVERY|XS_CTL_IGNORE_MEDIA_CHANGE))
227 		printf("%s: offline\n", device_xname(sc->sc_dev));
228 	else {
229 #define PLURAL(c)	(c) == 1 ? "" : "s"
230 		printf("%s: %d slot%s, %d drive%s, %d picker%s, %d portal%s\n",
231 		    device_xname(sc->sc_dev),
232 		    sc->sc_counts[CHET_ST], PLURAL(sc->sc_counts[CHET_ST]),
233 		    sc->sc_counts[CHET_DT], PLURAL(sc->sc_counts[CHET_DT]),
234 		    sc->sc_counts[CHET_MT], PLURAL(sc->sc_counts[CHET_MT]),
235 		    sc->sc_counts[CHET_IE], PLURAL(sc->sc_counts[CHET_IE]));
236 #undef PLURAL
237 #ifdef CHANGER_DEBUG
238 		printf("%s: move mask: 0x%x 0x%x 0x%x 0x%x\n",
239 		    device_xname(sc->sc_dev),
240 		    sc->sc_movemask[CHET_MT], sc->sc_movemask[CHET_ST],
241 		    sc->sc_movemask[CHET_IE], sc->sc_movemask[CHET_DT]);
242 		printf("%s: exchange mask: 0x%x 0x%x 0x%x 0x%x\n",
243 		    device_xname(sc->sc_dev),
244 		    sc->sc_exchangemask[CHET_MT], sc->sc_exchangemask[CHET_ST],
245 		    sc->sc_exchangemask[CHET_IE], sc->sc_exchangemask[CHET_DT]);
246 #endif /* CHANGER_DEBUG */
247 	}
248 
249 	/* Default the current picker. */
250 	sc->sc_picker = sc->sc_firsts[CHET_MT];
251 }
252 
253 static int
254 chopen(dev_t dev, int flags, int fmt, struct lwp *l)
255 {
256 	struct ch_softc *sc;
257 	struct scsipi_periph *periph;
258 	struct scsipi_adapter *adapt;
259 	int unit, error;
260 
261 	unit = CHUNIT(dev);
262 	sc = device_lookup_private(&ch_cd, unit);
263 	if (sc == NULL)
264 		return (ENXIO);
265 
266 	periph = sc->sc_periph;
267 	adapt = periph->periph_channel->chan_adapter;
268 
269 	/*
270 	 * Only allow one open at a time.
271 	 */
272 	if (periph->periph_flags & PERIPH_OPEN)
273 		return (EBUSY);
274 
275 	if ((error = scsipi_adapter_addref(adapt)) != 0)
276 		return (error);
277 
278 	/*
279 	 * Make sure the unit is on-line.  If a UNIT ATTENTION
280 	 * occurs, we will mark that an Init-Element-Status is
281 	 * needed in ch_get_params().
282 	 *
283 	 * We ignore NOT READY in case e.g a magazine isn't actually
284 	 * loaded into the changer or a tape isn't in the drive.
285 	 */
286 	error = scsipi_test_unit_ready(periph, XS_CTL_IGNORE_NOT_READY);
287 	if (error)
288 		goto bad;
289 
290 	periph->periph_flags |= PERIPH_OPEN;
291 
292 	/*
293 	 * Make sure our parameters are up to date.
294 	 */
295 	if ((error = ch_get_params(sc, 0)) != 0)
296 		goto bad;
297 
298 	return (0);
299 
300  bad:
301 	scsipi_adapter_delref(adapt);
302 	periph->periph_flags &= ~PERIPH_OPEN;
303 	return (error);
304 }
305 
306 static int
307 chclose(dev_t dev, int flags, int fmt, struct lwp *l)
308 {
309 	struct ch_softc *sc = device_lookup_private(&ch_cd, CHUNIT(dev));
310 	struct scsipi_periph *periph = sc->sc_periph;
311 	struct scsipi_adapter *adapt = periph->periph_channel->chan_adapter;
312 
313 	scsipi_wait_drain(periph);
314 
315 	scsipi_adapter_delref(adapt);
316 
317 	sc->sc_events = 0;
318 
319 	periph->periph_flags &= ~PERIPH_OPEN;
320 	return (0);
321 }
322 
323 static int
324 chread(dev_t dev, struct uio *uio, int flags)
325 {
326 	struct ch_softc *sc = device_lookup_private(&ch_cd, CHUNIT(dev));
327 	int error;
328 
329 	if (uio->uio_resid != CHANGER_EVENT_SIZE)
330 		return (EINVAL);
331 
332 	/*
333 	 * Read never blocks; if there are no events pending, we just
334 	 * return an all-clear bitmask.
335 	 */
336 	error = uiomove(&sc->sc_events, CHANGER_EVENT_SIZE, uio);
337 	if (error == 0)
338 		sc->sc_events = 0;
339 	return (error);
340 }
341 
342 static int
343 chioctl(dev_t dev, u_long cmd, void *data, int flags, struct lwp *l)
344 {
345 	struct ch_softc *sc = device_lookup_private(&ch_cd, CHUNIT(dev));
346 	int error = 0;
347 
348 	/*
349 	 * If this command can change the device's state, we must
350 	 * have the device open for writing.
351 	 */
352 	switch (cmd) {
353 	case CHIOGPICKER:
354 	case CHIOGPARAMS:
355 	case OCHIOGSTATUS:
356 		break;
357 
358 	default:
359 		if ((flags & FWRITE) == 0)
360 			return (EBADF);
361 	}
362 
363 	switch (cmd) {
364 	case CHIOMOVE:
365 		error = ch_move(sc, (struct changer_move_request *)data);
366 		break;
367 
368 	case CHIOEXCHANGE:
369 		error = ch_exchange(sc,
370 		    (struct changer_exchange_request *)data);
371 		break;
372 
373 	case CHIOPOSITION:
374 		error = ch_position(sc,
375 		    (struct changer_position_request *)data);
376 		break;
377 
378 	case CHIOGPICKER:
379 		*(int *)data = sc->sc_picker - sc->sc_firsts[CHET_MT];
380 		break;
381 
382 	case CHIOSPICKER:
383 	    {
384 		int new_picker = *(int *)data;
385 
386 		if (new_picker > (sc->sc_counts[CHET_MT] - 1))
387 			return (EINVAL);
388 		sc->sc_picker = sc->sc_firsts[CHET_MT] + new_picker;
389 		break;
390 	    }
391 
392 	case CHIOGPARAMS:
393 	    {
394 		struct changer_params *cp = (struct changer_params *)data;
395 
396 		cp->cp_curpicker = sc->sc_picker - sc->sc_firsts[CHET_MT];
397 		cp->cp_npickers = sc->sc_counts[CHET_MT];
398 		cp->cp_nslots = sc->sc_counts[CHET_ST];
399 		cp->cp_nportals = sc->sc_counts[CHET_IE];
400 		cp->cp_ndrives = sc->sc_counts[CHET_DT];
401 		break;
402 	    }
403 
404 	case CHIOIELEM:
405 		error = ch_ielem(sc);
406 		if (error == 0) {
407 			sc->sc_periph->periph_flags |= PERIPH_MEDIA_LOADED;
408 		}
409 		break;
410 
411 	case OCHIOGSTATUS:
412 	    {
413 		struct ochanger_element_status_request *cesr =
414 		    (struct ochanger_element_status_request *)data;
415 
416 		error = ch_ousergetelemstatus(sc, cesr->cesr_type,
417 		    cesr->cesr_data);
418 		break;
419 	    }
420 
421 	case CHIOGSTATUS:
422 		error = ch_usergetelemstatus(sc,
423 		    (struct changer_element_status_request *)data);
424 		break;
425 
426 	case CHIOSVOLTAG:
427 		error = ch_setvoltag(sc,
428 		    (struct changer_set_voltag_request *)data);
429 		break;
430 
431 	/* Implement prevent/allow? */
432 
433 	default:
434 		error = scsipi_do_ioctl(sc->sc_periph, dev, cmd, data,
435 		    flags, l);
436 		break;
437 	}
438 
439 	return (error);
440 }
441 
442 static int
443 chpoll(dev_t dev, int events, struct lwp *l)
444 {
445 	struct ch_softc *sc = device_lookup_private(&ch_cd, CHUNIT(dev));
446 	int revents;
447 
448 	revents = events & (POLLOUT | POLLWRNORM);
449 
450 	if ((events & (POLLIN | POLLRDNORM)) == 0)
451 		return (revents);
452 
453 	if (sc->sc_events == 0)
454 		revents |= events & (POLLIN | POLLRDNORM);
455 	else
456 		selrecord(l, &sc->sc_selq);
457 
458 	return (revents);
459 }
460 
461 static void
462 filt_chdetach(struct knote *kn)
463 {
464 	struct ch_softc *sc = kn->kn_hook;
465 
466 	SLIST_REMOVE(&sc->sc_selq.sel_klist, kn, knote, kn_selnext);
467 }
468 
469 static int
470 filt_chread(struct knote *kn, long hint)
471 {
472 	struct ch_softc *sc = kn->kn_hook;
473 
474 	if (sc->sc_events == 0)
475 		return (0);
476 	kn->kn_data = CHANGER_EVENT_SIZE;
477 	return (1);
478 }
479 
480 static const struct filterops chread_filtops =
481 	{ 1, NULL, filt_chdetach, filt_chread };
482 
483 static const struct filterops chwrite_filtops =
484 	{ 1, NULL, filt_chdetach, filt_seltrue };
485 
486 static int
487 chkqfilter(dev_t dev, struct knote *kn)
488 {
489 	struct ch_softc *sc = device_lookup_private(&ch_cd, CHUNIT(dev));
490 	struct klist *klist;
491 
492 	switch (kn->kn_filter) {
493 	case EVFILT_READ:
494 		klist = &sc->sc_selq.sel_klist;
495 		kn->kn_fop = &chread_filtops;
496 		break;
497 
498 	case EVFILT_WRITE:
499 		klist = &sc->sc_selq.sel_klist;
500 		kn->kn_fop = &chwrite_filtops;
501 		break;
502 
503 	default:
504 		return (EINVAL);
505 	}
506 
507 	kn->kn_hook = sc;
508 
509 	SLIST_INSERT_HEAD(klist, kn, kn_selnext);
510 
511 	return (0);
512 }
513 
514 static int
515 ch_interpret_sense(struct scsipi_xfer *xs)
516 {
517 	struct scsipi_periph *periph = xs->xs_periph;
518 	struct scsi_sense_data *sense = &xs->sense.scsi_sense;
519 	struct ch_softc *sc = device_private(periph->periph_dev);
520 	u_int16_t asc_ascq;
521 
522 	/*
523 	 * If the periph is already recovering, just do the
524 	 * normal error recovering.
525 	 */
526 	if (periph->periph_flags & PERIPH_RECOVERING)
527 		return (EJUSTRETURN);
528 
529 	/*
530 	 * If it isn't an extended or extended/deferred error, let
531 	 * the generic code handle it.
532 	 */
533 	if (SSD_RCODE(sense->response_code) != SSD_RCODE_CURRENT &&
534 	    SSD_RCODE(sense->response_code) != SSD_RCODE_DEFERRED)
535 		return (EJUSTRETURN);
536 
537 	/*
538 	 * We're only interested in condtions that
539 	 * indicate potential inventory violation.
540 	 *
541 	 * We use ASC/ASCQ codes for this.
542 	 */
543 
544 	asc_ascq = (((u_int16_t) sense->asc) << 8) |
545 	    sense->ascq;
546 
547 	switch (asc_ascq) {
548 	case 0x2800:
549 		/* "Not Ready To Ready Transition (Medium May Have Changed)" */
550 	case 0x2900:
551 		/* "Power On, Reset, or Bus Device Reset Occurred" */
552 		sc->sc_periph->periph_flags &= ~PERIPH_MEDIA_LOADED;
553 		/*
554 		 * Enqueue an Element-Status-Changed event, and wake up
555 		 * any processes waiting for them.
556 		 */
557 		if ((xs->xs_control & XS_CTL_IGNORE_MEDIA_CHANGE) == 0)
558 			ch_event(sc, CHEV_ELEMENT_STATUS_CHANGED);
559 		break;
560 	default:
561 		break;
562 	}
563 
564 	return (EJUSTRETURN);
565 }
566 
567 static void
568 ch_event(struct ch_softc *sc, u_int event)
569 {
570 
571 	sc->sc_events |= event;
572 	selnotify(&sc->sc_selq, 0, 0);
573 }
574 
575 static int
576 ch_move(struct ch_softc *sc, struct changer_move_request *cm)
577 {
578 	struct scsi_move_medium cmd;
579 	u_int16_t fromelem, toelem;
580 
581 	/*
582 	 * Check arguments.
583 	 */
584 	if ((cm->cm_fromtype > CHET_DT) || (cm->cm_totype > CHET_DT))
585 		return (EINVAL);
586 	if ((cm->cm_fromunit > (sc->sc_counts[cm->cm_fromtype] - 1)) ||
587 	    (cm->cm_tounit > (sc->sc_counts[cm->cm_totype] - 1)))
588 		return (ENODEV);
589 
590 	/*
591 	 * Check the request against the changer's capabilities.
592 	 */
593 	if ((sc->sc_movemask[cm->cm_fromtype] & (1 << cm->cm_totype)) == 0)
594 		return (ENODEV);
595 
596 	/*
597 	 * Calculate the source and destination elements.
598 	 */
599 	fromelem = sc->sc_firsts[cm->cm_fromtype] + cm->cm_fromunit;
600 	toelem = sc->sc_firsts[cm->cm_totype] + cm->cm_tounit;
601 
602 	/*
603 	 * Build the SCSI command.
604 	 */
605 	memset(&cmd, 0, sizeof(cmd));
606 	cmd.opcode = MOVE_MEDIUM;
607 	_lto2b(sc->sc_picker, cmd.tea);
608 	_lto2b(fromelem, cmd.src);
609 	_lto2b(toelem, cmd.dst);
610 	if (cm->cm_flags & CM_INVERT)
611 		cmd.flags |= MOVE_MEDIUM_INVERT;
612 
613 	/*
614 	 * Send command to changer.
615 	 */
616 	return (scsipi_command(sc->sc_periph, (void *)&cmd, sizeof(cmd), 0, 0,
617 	    CHRETRIES, CHTIMEOUT, NULL, 0));
618 }
619 
620 static int
621 ch_exchange(struct ch_softc *sc, struct changer_exchange_request *ce)
622 {
623 	struct scsi_exchange_medium cmd;
624 	u_int16_t src, dst1, dst2;
625 
626 	/*
627 	 * Check arguments.
628 	 */
629 	if ((ce->ce_srctype > CHET_DT) || (ce->ce_fdsttype > CHET_DT) ||
630 	    (ce->ce_sdsttype > CHET_DT))
631 		return (EINVAL);
632 	if ((ce->ce_srcunit > (sc->sc_counts[ce->ce_srctype] - 1)) ||
633 	    (ce->ce_fdstunit > (sc->sc_counts[ce->ce_fdsttype] - 1)) ||
634 	    (ce->ce_sdstunit > (sc->sc_counts[ce->ce_sdsttype] - 1)))
635 		return (ENODEV);
636 
637 	/*
638 	 * Check the request against the changer's capabilities.
639 	 */
640 	if (((sc->sc_exchangemask[ce->ce_srctype] &
641 	     (1 << ce->ce_fdsttype)) == 0) ||
642 	    ((sc->sc_exchangemask[ce->ce_fdsttype] &
643 	     (1 << ce->ce_sdsttype)) == 0))
644 		return (ENODEV);
645 
646 	/*
647 	 * Calculate the source and destination elements.
648 	 */
649 	src = sc->sc_firsts[ce->ce_srctype] + ce->ce_srcunit;
650 	dst1 = sc->sc_firsts[ce->ce_fdsttype] + ce->ce_fdstunit;
651 	dst2 = sc->sc_firsts[ce->ce_sdsttype] + ce->ce_sdstunit;
652 
653 	/*
654 	 * Build the SCSI command.
655 	 */
656 	memset(&cmd, 0, sizeof(cmd));
657 	cmd.opcode = EXCHANGE_MEDIUM;
658 	_lto2b(sc->sc_picker, cmd.tea);
659 	_lto2b(src, cmd.src);
660 	_lto2b(dst1, cmd.fdst);
661 	_lto2b(dst2, cmd.sdst);
662 	if (ce->ce_flags & CE_INVERT1)
663 		cmd.flags |= EXCHANGE_MEDIUM_INV1;
664 	if (ce->ce_flags & CE_INVERT2)
665 		cmd.flags |= EXCHANGE_MEDIUM_INV2;
666 
667 	/*
668 	 * Send command to changer.
669 	 */
670 	return (scsipi_command(sc->sc_periph, (void *)&cmd, sizeof(cmd), 0, 0,
671 	    CHRETRIES, CHTIMEOUT, NULL, 0));
672 }
673 
674 static int
675 ch_position(struct ch_softc *sc, struct changer_position_request *cp)
676 {
677 	struct scsi_position_to_element cmd;
678 	u_int16_t dst;
679 
680 	/*
681 	 * Check arguments.
682 	 */
683 	if (cp->cp_type > CHET_DT)
684 		return (EINVAL);
685 	if (cp->cp_unit > (sc->sc_counts[cp->cp_type] - 1))
686 		return (ENODEV);
687 
688 	/*
689 	 * Calculate the destination element.
690 	 */
691 	dst = sc->sc_firsts[cp->cp_type] + cp->cp_unit;
692 
693 	/*
694 	 * Build the SCSI command.
695 	 */
696 	memset(&cmd, 0, sizeof(cmd));
697 	cmd.opcode = POSITION_TO_ELEMENT;
698 	_lto2b(sc->sc_picker, cmd.tea);
699 	_lto2b(dst, cmd.dst);
700 	if (cp->cp_flags & CP_INVERT)
701 		cmd.flags |= POSITION_TO_ELEMENT_INVERT;
702 
703 	/*
704 	 * Send command to changer.
705 	 */
706 	return (scsipi_command(sc->sc_periph, (void *)&cmd, sizeof(cmd), 0, 0,
707 	    CHRETRIES, CHTIMEOUT, NULL, 0));
708 }
709 
710 /*
711  * Perform a READ ELEMENT STATUS on behalf of the user, and return to
712  * the user only the data the user is interested in.  This returns the
713  * old data format.
714  */
715 static int
716 ch_ousergetelemstatus(struct ch_softc *sc, int chet, u_int8_t *uptr)
717 {
718 	struct read_element_status_header *st_hdrp, st_hdr;
719 	struct read_element_status_page_header *pg_hdrp;
720 	struct read_element_status_descriptor *desc;
721 	size_t size, desclen;
722 	void *data;
723 	int avail, i, error = 0;
724 	u_int8_t user_data;
725 
726 	/*
727 	 * If there are no elements of the requested type in the changer,
728 	 * the request is invalid.
729 	 */
730 	if (sc->sc_counts[chet] == 0)
731 		return (EINVAL);
732 
733 	/*
734 	 * Do the request the user wants, but only read the status header.
735 	 * This will tell us the amount of storage we must allocate in
736 	 * order to read all data.
737 	 */
738 	error = ch_getelemstatus(sc, sc->sc_firsts[chet],
739 	    sc->sc_counts[chet], &st_hdr, sizeof(st_hdr), 0, 0);
740 	if (error)
741 		return (error);
742 
743 	size = sizeof(struct read_element_status_header) +
744 	    _3btol(st_hdr.nbytes);
745 
746 	/*
747 	 * We must have at least room for the status header and
748 	 * one page header (since we only ask for one element type
749 	 * at a time).
750 	 */
751 	if (size < (sizeof(struct read_element_status_header) +
752 	    sizeof(struct read_element_status_page_header)))
753 		return (EIO);
754 
755 	/*
756 	 * Allocate the storage and do the request again.
757 	 */
758 	data = malloc(size, M_DEVBUF, M_WAITOK);
759 	error = ch_getelemstatus(sc, sc->sc_firsts[chet],
760 	    sc->sc_counts[chet], data, size, 0, 0);
761 	if (error)
762 		goto done;
763 
764 	st_hdrp = (struct read_element_status_header *)data;
765 	pg_hdrp = (struct read_element_status_page_header *)((u_long)st_hdrp +
766 	    sizeof(struct read_element_status_header));
767 	desclen = _2btol(pg_hdrp->edl);
768 
769 	/*
770 	 * Fill in the user status array.
771 	 */
772 	avail = _2btol(st_hdrp->count);
773 
774 	if (avail != sc->sc_counts[chet])
775 		printf("%s: warning, READ ELEMENT STATUS avail != count\n",
776 		    device_xname(sc->sc_dev));
777 
778 	desc = (struct read_element_status_descriptor *)((u_long)data +
779 	    sizeof(struct read_element_status_header) +
780 	    sizeof(struct read_element_status_page_header));
781 	for (i = 0; i < avail; ++i) {
782 		user_data = desc->flags1;
783 		error = copyout(&user_data, &uptr[i], avail);
784 		if (error)
785 			break;
786 		desc = (struct read_element_status_descriptor *)((u_long)desc
787 		    + desclen);
788 	}
789 
790  done:
791 	if (data != NULL)
792 		free(data, M_DEVBUF);
793 	return (error);
794 }
795 
796 /*
797  * Perform a READ ELEMENT STATUS on behalf of the user.  This returns
798  * the new (more complete) data format.
799  */
800 static int
801 ch_usergetelemstatus(struct ch_softc *sc,
802     struct changer_element_status_request *cesr)
803 {
804 	struct scsipi_channel *chan = sc->sc_periph->periph_channel;
805 	struct scsipi_periph *dtperiph;
806 	struct read_element_status_header *st_hdrp, st_hdr;
807 	struct read_element_status_page_header *pg_hdrp;
808 	struct read_element_status_descriptor *desc;
809 	struct changer_volume_tag *avol, *pvol;
810 	size_t size, desclen, stddesclen, offset;
811 	int first, avail, i, error = 0;
812 	void *data;
813 	void *uvendptr;
814 	struct changer_element_status ces;
815 
816 	/*
817 	 * Check arguments.
818 	 */
819 	if (cesr->cesr_type > CHET_DT)
820 		return (EINVAL);
821 	if (sc->sc_counts[cesr->cesr_type] == 0)
822 		return (ENODEV);
823 	if (cesr->cesr_unit > (sc->sc_counts[cesr->cesr_type] - 1))
824 		return (ENODEV);
825 	if (cesr->cesr_count >
826 	    (sc->sc_counts[cesr->cesr_type] + cesr->cesr_unit))
827 		return (EINVAL);
828 
829 	/*
830 	 * Do the request the user wants, but only read the status header.
831 	 * This will tell us the amount of storage we must allocate
832 	 * in order to read all the data.
833 	 */
834 	error = ch_getelemstatus(sc, sc->sc_firsts[cesr->cesr_type] +
835 	    cesr->cesr_unit, cesr->cesr_count, &st_hdr, sizeof(st_hdr), 0,
836 	    cesr->cesr_flags);
837 	if (error)
838 		return (error);
839 
840 	size = sizeof(struct read_element_status_header) +
841 	    _3btol(st_hdr.nbytes);
842 
843 	/*
844 	 * We must have at least room for the status header and
845 	 * one page header (since we only ask for oen element type
846 	 * at a time).
847 	 */
848 	if (size < (sizeof(struct read_element_status_header) +
849 	    sizeof(struct read_element_status_page_header)))
850 		return (EIO);
851 
852 	/*
853 	 * Allocate the storage and do the request again.
854 	 */
855 	data = malloc(size, M_DEVBUF, M_WAITOK);
856 	error = ch_getelemstatus(sc, sc->sc_firsts[cesr->cesr_type] +
857 	    cesr->cesr_unit, cesr->cesr_count, data, size, 0,
858 	    cesr->cesr_flags);
859 	if (error)
860 		goto done;
861 
862 	st_hdrp = (struct read_element_status_header *)data;
863 	pg_hdrp = (struct read_element_status_page_header *)((u_long)st_hdrp +
864 	    sizeof(struct read_element_status_header));
865 	desclen = _2btol(pg_hdrp->edl);
866 
867 	/*
868 	 * Fill in the user status array.
869 	 */
870 	first = _2btol(st_hdrp->fear);
871 	if (first <  (sc->sc_firsts[cesr->cesr_type] + cesr->cesr_unit) ||
872 	    first >= (sc->sc_firsts[cesr->cesr_type] + cesr->cesr_unit +
873 		      cesr->cesr_count)) {
874 		error = EIO;
875 		goto done;
876 	}
877 	first -= sc->sc_firsts[cesr->cesr_type] + cesr->cesr_unit;
878 
879 	avail = _2btol(st_hdrp->count);
880 	if (avail <= 0 || avail > cesr->cesr_count) {
881 		error = EIO;
882 		goto done;
883 	}
884 
885 	offset = sizeof(struct read_element_status_header) +
886 		 sizeof(struct read_element_status_page_header);
887 
888 	for (i = 0; i < cesr->cesr_count; i++) {
889 		memset(&ces, 0, sizeof(ces));
890 		if (i < first || i >= (first + avail)) {
891 			error = copyout(&ces, &cesr->cesr_data[i],
892 			    sizeof(ces));
893 			if (error)
894 				goto done;
895 		}
896 
897 		desc = (struct read_element_status_descriptor *)
898 		    ((char *)data + offset);
899 		stddesclen = sizeof(struct read_element_status_descriptor);
900 		offset += desclen;
901 
902 		ces.ces_flags = CESTATUS_STATUS_VALID;
903 
904 		/*
905 		 * The SCSI flags conveniently map directly to the
906 		 * chio API flags.
907 		 */
908 		ces.ces_flags |= (desc->flags1 & 0x3f);
909 
910 		ces.ces_asc = desc->sense_code;
911 		ces.ces_ascq = desc->sense_qual;
912 
913 		/*
914 		 * For Data Transport elemenets, get the SCSI ID and LUN,
915 		 * and attempt to map them to a device name if they're
916 		 * on the same SCSI bus.
917 		 */
918 		if (desc->dt_scsi_flags & READ_ELEMENT_STATUS_DT_IDVALID) {
919 			ces.ces_target = desc->dt_scsi_addr;
920 			ces.ces_flags |= CESTATUS_TARGET_VALID;
921 		}
922 		if (desc->dt_scsi_flags & READ_ELEMENT_STATUS_DT_LUVALID) {
923 			ces.ces_lun = desc->dt_scsi_flags &
924 			    READ_ELEMENT_STATUS_DT_LUNMASK;
925 			ces.ces_flags |= CESTATUS_LUN_VALID;
926 		}
927 		if (desc->dt_scsi_flags & READ_ELEMENT_STATUS_DT_NOTBUS)
928 			ces.ces_flags |= CESTATUS_NOTBUS;
929 		else if ((ces.ces_flags &
930 			  (CESTATUS_TARGET_VALID|CESTATUS_LUN_VALID)) ==
931 			 (CESTATUS_TARGET_VALID|CESTATUS_LUN_VALID)) {
932 			if (ces.ces_target < chan->chan_ntargets &&
933 			    ces.ces_lun < chan->chan_nluns &&
934 			    (dtperiph = scsipi_lookup_periph(chan,
935 			     ces.ces_target, ces.ces_lun)) != NULL &&
936 			    dtperiph->periph_dev != NULL) {
937 				strlcpy(ces.ces_xname,
938 				    device_xname(dtperiph->periph_dev),
939 				    sizeof(ces.ces_xname));
940 				ces.ces_flags |= CESTATUS_XNAME_VALID;
941 			}
942 		}
943 
944 		if (desc->flags2 & READ_ELEMENT_STATUS_INVERT)
945 			ces.ces_flags |= CESTATUS_INVERTED;
946 
947 		if (desc->flags2 & READ_ELEMENT_STATUS_SVALID) {
948 			if (ch_map_element(sc, _2btol(desc->ssea),
949 			    &ces.ces_from_type, &ces.ces_from_unit))
950 				ces.ces_flags |= CESTATUS_FROM_VALID;
951 		}
952 
953 		/*
954 		 * Extract volume tag information.
955 		 */
956 		switch (pg_hdrp->flags &
957 		    (READ_ELEMENT_STATUS_PVOLTAG|READ_ELEMENT_STATUS_AVOLTAG)) {
958 		case (READ_ELEMENT_STATUS_PVOLTAG|READ_ELEMENT_STATUS_AVOLTAG):
959 			pvol = (struct changer_volume_tag *)(desc + 1);
960 			avol = pvol + 1;
961 			break;
962 
963 		case READ_ELEMENT_STATUS_PVOLTAG:
964 			pvol = (struct changer_volume_tag *)(desc + 1);
965 			avol = NULL;
966 			break;
967 
968 		case READ_ELEMENT_STATUS_AVOLTAG:
969 			pvol = NULL;
970 			avol = (struct changer_volume_tag *)(desc + 1);
971 			break;
972 
973 		default:
974 			avol = pvol = NULL;
975 			break;
976 		}
977 
978 		if (pvol != NULL) {
979 			ch_voltag_convert_in(pvol, &ces.ces_pvoltag);
980 			ces.ces_flags |= CESTATUS_PVOL_VALID;
981 			stddesclen += sizeof(struct changer_volume_tag);
982 		}
983 		if (avol != NULL) {
984 			ch_voltag_convert_in(avol, &ces.ces_avoltag);
985 			ces.ces_flags |= CESTATUS_AVOL_VALID;
986 			stddesclen += sizeof(struct changer_volume_tag);
987 		}
988 
989 		/*
990 		 * Compute vendor-specific length.  Note the 4 reserved
991 		 * bytes between the volume tags and the vendor-specific
992 		 * data.  Copy it out of the user wants it.
993 		 */
994 		stddesclen += 4;
995 		if (desclen > stddesclen)
996 			ces.ces_vendor_len = desclen - stddesclen;
997 
998 		if (ces.ces_vendor_len != 0 && cesr->cesr_vendor_data != NULL) {
999 			error = copyin(&cesr->cesr_vendor_data[i], &uvendptr,
1000 			    sizeof(uvendptr));
1001 			if (error)
1002 				goto done;
1003 			error = copyout((void *)((u_long)desc + stddesclen),
1004 			    uvendptr, ces.ces_vendor_len);
1005 			if (error)
1006 				goto done;
1007 		}
1008 
1009 		/*
1010 		 * Now copy out the status descriptor we've constructed.
1011 		 */
1012 		error = copyout(&ces, &cesr->cesr_data[i], sizeof(ces));
1013 		if (error)
1014 			goto done;
1015 	}
1016 
1017  done:
1018 	if (data != NULL)
1019 		free(data, M_DEVBUF);
1020 	return (error);
1021 }
1022 
1023 static int
1024 ch_getelemstatus(struct ch_softc *sc, int first, int count, void *data,
1025     size_t datalen, int scsiflags, int flags)
1026 {
1027 	struct scsi_read_element_status cmd;
1028 
1029 	/*
1030 	 * Build SCSI command.
1031 	 */
1032 	memset(&cmd, 0, sizeof(cmd));
1033 	cmd.opcode = READ_ELEMENT_STATUS;
1034 	cmd.byte2 = ELEMENT_TYPE_ALL;
1035 	if (flags & CESR_VOLTAGS)
1036 		cmd.byte2 |= READ_ELEMENT_STATUS_VOLTAG;
1037 	_lto2b(first, cmd.sea);
1038 	_lto2b(count, cmd.count);
1039 	_lto3b(datalen, cmd.len);
1040 
1041 	/*
1042 	 * Send command to changer.
1043 	 */
1044 	return (scsipi_command(sc->sc_periph, (void *)&cmd, sizeof(cmd),
1045 	    (void *)data, datalen,
1046 	    CHRETRIES, CHTIMEOUT, NULL, scsiflags | XS_CTL_DATA_IN));
1047 }
1048 
1049 static int
1050 ch_setvoltag(struct ch_softc *sc, struct changer_set_voltag_request *csvr)
1051 {
1052 	struct scsi_send_volume_tag cmd;
1053 	struct changer_volume_tag voltag;
1054 	void *data = NULL;
1055 	size_t datalen = 0;
1056 	int error;
1057 	u_int16_t dst;
1058 
1059 	/*
1060 	 * Check arguments.
1061 	 */
1062 	if (csvr->csvr_type > CHET_DT)
1063 		return (EINVAL);
1064 	if (csvr->csvr_unit > (sc->sc_counts[csvr->csvr_type] - 1))
1065 		return (ENODEV);
1066 
1067 	dst = sc->sc_firsts[csvr->csvr_type] + csvr->csvr_unit;
1068 
1069 	/*
1070 	 * Build the SCSI command.
1071 	 */
1072 	memset(&cmd, 0, sizeof(cmd));
1073 	cmd.opcode = SEND_VOLUME_TAG;
1074 	_lto2b(dst, cmd.eaddr);
1075 
1076 #define	ALTERNATE	(csvr->csvr_flags & CSVR_ALTERNATE)
1077 
1078 	switch (csvr->csvr_flags & CSVR_MODE_MASK) {
1079 	case CSVR_MODE_SET:
1080 		cmd.sac = ALTERNATE ? SAC_ASSERT_ALT : SAC_ASSERT_PRIMARY;
1081 		break;
1082 
1083 	case CSVR_MODE_REPLACE:
1084 		cmd.sac = ALTERNATE ? SAC_REPLACE_ALT : SAC_REPLACE_PRIMARY;
1085 		break;
1086 
1087 	case CSVR_MODE_CLEAR:
1088 		cmd.sac = ALTERNATE ? SAC_UNDEFINED_ALT : SAC_UNDEFINED_PRIMARY;
1089 		break;
1090 
1091 	default:
1092 		return (EINVAL);
1093 	}
1094 
1095 #undef ALTERNATE
1096 
1097 	if (cmd.sac < SAC_UNDEFINED_PRIMARY) {
1098 		error = ch_voltag_convert_out(&csvr->csvr_voltag, &voltag);
1099 		if (error)
1100 			return (error);
1101 		data = &voltag;
1102 		datalen = sizeof(voltag);
1103 		_lto2b(datalen, cmd.length);
1104 	}
1105 
1106 	/*
1107 	 * Send command to changer.
1108 	 */
1109 	return (scsipi_command(sc->sc_periph, (void *)&cmd, sizeof(cmd),
1110 	    (void *)data, datalen, CHRETRIES, CHTIMEOUT, NULL,
1111 	    datalen ? XS_CTL_DATA_OUT : 0));
1112 }
1113 
1114 static int
1115 ch_ielem(struct ch_softc *sc)
1116 {
1117 	int tmo;
1118 	struct scsi_initialize_element_status cmd;
1119 
1120 	/*
1121 	 * Build SCSI command.
1122 	 */
1123 	memset(&cmd, 0, sizeof(cmd));
1124 	cmd.opcode = INITIALIZE_ELEMENT_STATUS;
1125 
1126 	/*
1127 	 * Send command to changer.
1128 	 *
1129 	 * The problem is, how long to allow for the command?
1130 	 * It can take a *really* long time, and also depends
1131 	 * on unknowable factors such as whether there are
1132 	 * *almost* readable labels on tapes that a barcode
1133 	 * reader is trying to decipher.
1134 	 *
1135 	 * I'm going to make this long enough to allow 5 minutes
1136 	 * per element plus an initial 10 minute wait.
1137 	 */
1138 	tmo =	sc->sc_counts[CHET_MT] +
1139 		sc->sc_counts[CHET_ST] +
1140 		sc->sc_counts[CHET_IE] +
1141 		sc->sc_counts[CHET_DT];
1142 	tmo *= 5 * 60 * 1000;
1143 	tmo += (10 * 60 * 1000);
1144 
1145 	return (scsipi_command(sc->sc_periph, (void *)&cmd, sizeof(cmd), 0, 0,
1146 	    CHRETRIES, tmo, NULL, XS_CTL_IGNORE_ILLEGAL_REQUEST));
1147 }
1148 
1149 /*
1150  * Ask the device about itself and fill in the parameters in our
1151  * softc.
1152  */
1153 static int
1154 ch_get_params(struct ch_softc *sc, int scsiflags)
1155 {
1156 	struct scsi_mode_sense_data {
1157 		struct scsi_mode_parameter_header_6 header;
1158 		union {
1159 			struct page_element_address_assignment ea;
1160 			struct page_transport_geometry_parameters tg;
1161 			struct page_device_capabilities cap;
1162 		} pages;
1163 	} sense_data;
1164 	int error, from;
1165 	u_int8_t *moves, *exchanges;
1166 
1167 	/*
1168 	 * Grab info from the element address assignment page.
1169 	 */
1170 	memset(&sense_data, 0, sizeof(sense_data));
1171 	error = scsipi_mode_sense(sc->sc_periph, SMS_DBD, 0x1d,
1172 	    &sense_data.header, sizeof(sense_data),
1173 	    scsiflags, CHRETRIES, 6000);
1174 	if (error) {
1175 		aprint_error_dev(sc->sc_dev, "could not sense element address page\n");
1176 		return (error);
1177 	}
1178 
1179 	sc->sc_firsts[CHET_MT] = _2btol(sense_data.pages.ea.mtea);
1180 	sc->sc_counts[CHET_MT] = _2btol(sense_data.pages.ea.nmte);
1181 	sc->sc_firsts[CHET_ST] = _2btol(sense_data.pages.ea.fsea);
1182 	sc->sc_counts[CHET_ST] = _2btol(sense_data.pages.ea.nse);
1183 	sc->sc_firsts[CHET_IE] = _2btol(sense_data.pages.ea.fieea);
1184 	sc->sc_counts[CHET_IE] = _2btol(sense_data.pages.ea.niee);
1185 	sc->sc_firsts[CHET_DT] = _2btol(sense_data.pages.ea.fdtea);
1186 	sc->sc_counts[CHET_DT] = _2btol(sense_data.pages.ea.ndte);
1187 
1188 	/* XXX ask for transport geometry page XXX */
1189 
1190 	/*
1191 	 * Grab info from the capabilities page.
1192 	 */
1193 	memset(&sense_data, 0, sizeof(sense_data));
1194 	/*
1195 	 * XXX: Note: not all changers can deal with disabled block descriptors
1196 	 */
1197 	error = scsipi_mode_sense(sc->sc_periph, SMS_DBD, 0x1f,
1198 	    &sense_data.header, sizeof(sense_data),
1199 	    scsiflags, CHRETRIES, 6000);
1200 	if (error) {
1201 		aprint_error_dev(sc->sc_dev, "could not sense capabilities page\n");
1202 		return (error);
1203 	}
1204 
1205 	memset(sc->sc_movemask, 0, sizeof(sc->sc_movemask));
1206 	memset(sc->sc_exchangemask, 0, sizeof(sc->sc_exchangemask));
1207 	moves = &sense_data.pages.cap.move_from_mt;
1208 	exchanges = &sense_data.pages.cap.exchange_with_mt;
1209 	for (from = CHET_MT; from <= CHET_DT; ++from) {
1210 		sc->sc_movemask[from] = moves[from];
1211 		sc->sc_exchangemask[from] = exchanges[from];
1212 	}
1213 
1214 #ifdef CH_AUTOMATIC_IELEM_POLICY
1215 	/*
1216 	 * If we need to do an Init-Element-Status,
1217 	 * do that now that we know what's in the changer.
1218 	 */
1219 	if ((scsiflags & XS_CTL_IGNORE_MEDIA_CHANGE) == 0) {
1220 		if ((sc->sc_periph->periph_flags & PERIPH_MEDIA_LOADED) == 0)
1221 			error = ch_ielem(sc);
1222 		if (error == 0)
1223 			sc->sc_periph->periph_flags |= PERIPH_MEDIA_LOADED;
1224 		else
1225 			sc->sc_periph->periph_flags &= ~PERIPH_MEDIA_LOADED;
1226 	}
1227 #endif
1228 	return (error);
1229 }
1230 
1231 static void
1232 ch_get_quirks(struct ch_softc *sc, struct scsipi_inquiry_pattern *inqbuf)
1233 {
1234 	const struct chquirk *match;
1235 	int priority;
1236 
1237 	sc->sc_settledelay = 0;
1238 
1239 	match = scsipi_inqmatch(inqbuf, chquirks,
1240 	    sizeof(chquirks) / sizeof(chquirks[0]),
1241 	    sizeof(chquirks[0]), &priority);
1242 	if (priority != 0)
1243 		sc->sc_settledelay = match->cq_settledelay;
1244 }
1245 
1246 static int
1247 ch_map_element(struct ch_softc *sc, u_int16_t elem, int *typep, int *unitp)
1248 {
1249 	int chet;
1250 
1251 	for (chet = CHET_MT; chet <= CHET_DT; chet++) {
1252 		if (elem >= sc->sc_firsts[chet] &&
1253 		    elem < (sc->sc_firsts[chet] + sc->sc_counts[chet])) {
1254 			*typep = chet;
1255 			*unitp = elem - sc->sc_firsts[chet];
1256 			return (1);
1257 		}
1258 	}
1259 	return (0);
1260 }
1261 
1262 static void
1263 ch_voltag_convert_in(const struct changer_volume_tag *sv,
1264     struct changer_voltag *cv)
1265 {
1266 	int i;
1267 
1268 	memset(cv, 0, sizeof(struct changer_voltag));
1269 
1270 	/*
1271 	 * Copy the volume tag string from the SCSI representation.
1272 	 * Per the SCSI-2 spec, we stop at the first blank character.
1273 	 */
1274 	for (i = 0; i < sizeof(sv->volid); i++) {
1275 		if (sv->volid[i] == ' ')
1276 			break;
1277 		cv->cv_tag[i] = sv->volid[i];
1278 	}
1279 	cv->cv_tag[i] = '\0';
1280 
1281 	cv->cv_serial = _2btol(sv->volseq);
1282 }
1283 
1284 static int
1285 ch_voltag_convert_out(const struct changer_voltag *cv,
1286     struct changer_volume_tag *sv)
1287 {
1288 	int i;
1289 
1290 	memset(sv, ' ', sizeof(struct changer_volume_tag));
1291 
1292 	for (i = 0; i < sizeof(sv->volid); i++) {
1293 		if (cv->cv_tag[i] == '\0')
1294 			break;
1295 		/*
1296 		 * Limit the character set to what is suggested in
1297 		 * the SCSI-2 spec.
1298 		 */
1299 		if ((cv->cv_tag[i] < '0' || cv->cv_tag[i] > '9') &&
1300 		    (cv->cv_tag[i] < 'A' || cv->cv_tag[i] > 'Z') &&
1301 		    (cv->cv_tag[i] != '_'))
1302 			return (EINVAL);
1303 		sv->volid[i] = cv->cv_tag[i];
1304 	}
1305 
1306 	_lto2b(cv->cv_serial, sv->volseq);
1307 
1308 	return (0);
1309 }
1310