xref: /netbsd-src/sys/dev/scsipi/ch.c (revision b7b7574d3bf8eeb51a1fa3977b59142ec6434a55)
1 /*	$NetBSD: ch.c,v 1.89 2014/03/16 05:20:29 dholland 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 1.89 2014/03/16 05:20:29 dholland 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 	.d_open = chopen,
125 	.d_close = chclose,
126 	.d_read = chread,
127 	.d_write = nowrite,
128 	.d_ioctl = chioctl,
129 	.d_stop = nostop,
130 	.d_tty = notty,
131 	.d_poll = chpoll,
132 	.d_mmap = nommap,
133 	.d_kqfilter = chkqfilter,
134 	.d_flag = D_OTHER
135 };
136 
137 /* SCSI glue */
138 static int	ch_interpret_sense(struct scsipi_xfer *);
139 
140 static const struct scsipi_periphsw ch_switch = {
141 	ch_interpret_sense,	/* check our error handler first */
142 	NULL,			/* no queue; our commands are synchronous */
143 	NULL,			/* have no async handler */
144 	NULL,			/* nothing to be done when xfer is done */
145 };
146 
147 static int	ch_move(struct ch_softc *, struct changer_move_request *);
148 static int	ch_exchange(struct ch_softc *,
149 		    struct changer_exchange_request *);
150 static int	ch_position(struct ch_softc *,
151 		    struct changer_position_request *);
152 static int	ch_ielem(struct ch_softc *);
153 static int	ch_ousergetelemstatus(struct ch_softc *, int, u_int8_t *);
154 static int	ch_usergetelemstatus(struct ch_softc *,
155 		    struct changer_element_status_request *);
156 static int	ch_getelemstatus(struct ch_softc *, int, int, void *,
157 		    size_t, int, int);
158 static int	ch_setvoltag(struct ch_softc *,
159 		    struct changer_set_voltag_request *);
160 static int	ch_get_params(struct ch_softc *, int);
161 static void	ch_get_quirks(struct ch_softc *,
162 		    struct scsipi_inquiry_pattern *);
163 static void	ch_event(struct ch_softc *, u_int);
164 static int	ch_map_element(struct ch_softc *, u_int16_t, int *, int *);
165 
166 static void	ch_voltag_convert_in(const struct changer_volume_tag *,
167 		    struct changer_voltag *);
168 static int	ch_voltag_convert_out(const struct changer_voltag *,
169 		    struct changer_volume_tag *);
170 
171 /*
172  * SCSI changer quirks.
173  */
174 struct chquirk {
175 	struct	scsipi_inquiry_pattern cq_match; /* device id pattern */
176 	int	cq_settledelay;	/* settle delay, in seconds */
177 };
178 
179 static const struct chquirk chquirks[] = {
180 	{{T_CHANGER, T_REMOV,
181 	  "SPECTRA",	"9000",		"0200"},
182 	 75},
183 };
184 
185 static int
186 chmatch(device_t parent, cfdata_t match,
187     void *aux)
188 {
189 	struct scsipibus_attach_args *sa = aux;
190 	int priority;
191 
192 	(void)scsipi_inqmatch(&sa->sa_inqbuf,
193 	    (void *)ch_patterns, sizeof(ch_patterns) / sizeof(ch_patterns[0]),
194 	    sizeof(ch_patterns[0]), &priority);
195 
196 	return (priority);
197 }
198 
199 static void
200 chattach(device_t parent, device_t self, void *aux)
201 {
202 	struct ch_softc *sc = device_private(self);
203 	struct scsipibus_attach_args *sa = aux;
204 	struct scsipi_periph *periph = sa->sa_periph;
205 
206 	sc->sc_dev = self;
207 	selinit(&sc->sc_selq);
208 
209 	/* Glue into the SCSI bus */
210 	sc->sc_periph = periph;
211 	periph->periph_dev = sc->sc_dev;
212 	periph->periph_switch = &ch_switch;
213 
214 	printf("\n");
215 
216 	/*
217 	 * Find out our device's quirks.
218 	 */
219 	ch_get_quirks(sc, &sa->sa_inqbuf);
220 
221 	/*
222 	 * Some changers require a long time to settle out, to do
223 	 * tape inventory, for instance.
224 	 */
225 	if (sc->sc_settledelay) {
226 		printf("%s: waiting %d seconds for changer to settle...\n",
227 		    device_xname(sc->sc_dev), sc->sc_settledelay);
228 		delay(1000000 * sc->sc_settledelay);
229 	}
230 
231 	/*
232 	 * Get information about the device.  Note we can't use
233 	 * interrupts yet.
234 	 */
235 	if (ch_get_params(sc, XS_CTL_DISCOVERY|XS_CTL_IGNORE_MEDIA_CHANGE))
236 		printf("%s: offline\n", device_xname(sc->sc_dev));
237 	else {
238 #define PLURAL(c)	(c) == 1 ? "" : "s"
239 		printf("%s: %d slot%s, %d drive%s, %d picker%s, %d portal%s\n",
240 		    device_xname(sc->sc_dev),
241 		    sc->sc_counts[CHET_ST], PLURAL(sc->sc_counts[CHET_ST]),
242 		    sc->sc_counts[CHET_DT], PLURAL(sc->sc_counts[CHET_DT]),
243 		    sc->sc_counts[CHET_MT], PLURAL(sc->sc_counts[CHET_MT]),
244 		    sc->sc_counts[CHET_IE], PLURAL(sc->sc_counts[CHET_IE]));
245 #undef PLURAL
246 #ifdef CHANGER_DEBUG
247 		printf("%s: move mask: 0x%x 0x%x 0x%x 0x%x\n",
248 		    device_xname(sc->sc_dev),
249 		    sc->sc_movemask[CHET_MT], sc->sc_movemask[CHET_ST],
250 		    sc->sc_movemask[CHET_IE], sc->sc_movemask[CHET_DT]);
251 		printf("%s: exchange mask: 0x%x 0x%x 0x%x 0x%x\n",
252 		    device_xname(sc->sc_dev),
253 		    sc->sc_exchangemask[CHET_MT], sc->sc_exchangemask[CHET_ST],
254 		    sc->sc_exchangemask[CHET_IE], sc->sc_exchangemask[CHET_DT]);
255 #endif /* CHANGER_DEBUG */
256 	}
257 
258 	/* Default the current picker. */
259 	sc->sc_picker = sc->sc_firsts[CHET_MT];
260 }
261 
262 static int
263 chopen(dev_t dev, int flags, int fmt, struct lwp *l)
264 {
265 	struct ch_softc *sc;
266 	struct scsipi_periph *periph;
267 	struct scsipi_adapter *adapt;
268 	int unit, error;
269 
270 	unit = CHUNIT(dev);
271 	sc = device_lookup_private(&ch_cd, unit);
272 	if (sc == NULL)
273 		return (ENXIO);
274 
275 	periph = sc->sc_periph;
276 	adapt = periph->periph_channel->chan_adapter;
277 
278 	/*
279 	 * Only allow one open at a time.
280 	 */
281 	if (periph->periph_flags & PERIPH_OPEN)
282 		return (EBUSY);
283 
284 	if ((error = scsipi_adapter_addref(adapt)) != 0)
285 		return (error);
286 
287 	/*
288 	 * Make sure the unit is on-line.  If a UNIT ATTENTION
289 	 * occurs, we will mark that an Init-Element-Status is
290 	 * needed in ch_get_params().
291 	 *
292 	 * We ignore NOT READY in case e.g a magazine isn't actually
293 	 * loaded into the changer or a tape isn't in the drive.
294 	 */
295 	error = scsipi_test_unit_ready(periph, XS_CTL_IGNORE_NOT_READY);
296 	if (error)
297 		goto bad;
298 
299 	periph->periph_flags |= PERIPH_OPEN;
300 
301 	/*
302 	 * Make sure our parameters are up to date.
303 	 */
304 	if ((error = ch_get_params(sc, 0)) != 0)
305 		goto bad;
306 
307 	return (0);
308 
309  bad:
310 	scsipi_adapter_delref(adapt);
311 	periph->periph_flags &= ~PERIPH_OPEN;
312 	return (error);
313 }
314 
315 static int
316 chclose(dev_t dev, int flags, int fmt, struct lwp *l)
317 {
318 	struct ch_softc *sc = device_lookup_private(&ch_cd, CHUNIT(dev));
319 	struct scsipi_periph *periph = sc->sc_periph;
320 	struct scsipi_adapter *adapt = periph->periph_channel->chan_adapter;
321 
322 	scsipi_wait_drain(periph);
323 
324 	scsipi_adapter_delref(adapt);
325 
326 	sc->sc_events = 0;
327 
328 	periph->periph_flags &= ~PERIPH_OPEN;
329 	return (0);
330 }
331 
332 static int
333 chread(dev_t dev, struct uio *uio, int flags)
334 {
335 	struct ch_softc *sc = device_lookup_private(&ch_cd, CHUNIT(dev));
336 	int error;
337 
338 	if (uio->uio_resid != CHANGER_EVENT_SIZE)
339 		return (EINVAL);
340 
341 	/*
342 	 * Read never blocks; if there are no events pending, we just
343 	 * return an all-clear bitmask.
344 	 */
345 	error = uiomove(&sc->sc_events, CHANGER_EVENT_SIZE, uio);
346 	if (error == 0)
347 		sc->sc_events = 0;
348 	return (error);
349 }
350 
351 static int
352 chioctl(dev_t dev, u_long cmd, void *data, int flags, struct lwp *l)
353 {
354 	struct ch_softc *sc = device_lookup_private(&ch_cd, CHUNIT(dev));
355 	int error = 0;
356 
357 	/*
358 	 * If this command can change the device's state, we must
359 	 * have the device open for writing.
360 	 */
361 	switch (cmd) {
362 	case CHIOGPICKER:
363 	case CHIOGPARAMS:
364 	case OCHIOGSTATUS:
365 		break;
366 
367 	default:
368 		if ((flags & FWRITE) == 0)
369 			return (EBADF);
370 	}
371 
372 	switch (cmd) {
373 	case CHIOMOVE:
374 		error = ch_move(sc, (struct changer_move_request *)data);
375 		break;
376 
377 	case CHIOEXCHANGE:
378 		error = ch_exchange(sc,
379 		    (struct changer_exchange_request *)data);
380 		break;
381 
382 	case CHIOPOSITION:
383 		error = ch_position(sc,
384 		    (struct changer_position_request *)data);
385 		break;
386 
387 	case CHIOGPICKER:
388 		*(int *)data = sc->sc_picker - sc->sc_firsts[CHET_MT];
389 		break;
390 
391 	case CHIOSPICKER:
392 	    {
393 		int new_picker = *(int *)data;
394 
395 		if (new_picker > (sc->sc_counts[CHET_MT] - 1))
396 			return (EINVAL);
397 		sc->sc_picker = sc->sc_firsts[CHET_MT] + new_picker;
398 		break;
399 	    }
400 
401 	case CHIOGPARAMS:
402 	    {
403 		struct changer_params *cp = (struct changer_params *)data;
404 
405 		cp->cp_curpicker = sc->sc_picker - sc->sc_firsts[CHET_MT];
406 		cp->cp_npickers = sc->sc_counts[CHET_MT];
407 		cp->cp_nslots = sc->sc_counts[CHET_ST];
408 		cp->cp_nportals = sc->sc_counts[CHET_IE];
409 		cp->cp_ndrives = sc->sc_counts[CHET_DT];
410 		break;
411 	    }
412 
413 	case CHIOIELEM:
414 		error = ch_ielem(sc);
415 		if (error == 0) {
416 			sc->sc_periph->periph_flags |= PERIPH_MEDIA_LOADED;
417 		}
418 		break;
419 
420 	case OCHIOGSTATUS:
421 	    {
422 		struct ochanger_element_status_request *cesr =
423 		    (struct ochanger_element_status_request *)data;
424 
425 		error = ch_ousergetelemstatus(sc, cesr->cesr_type,
426 		    cesr->cesr_data);
427 		break;
428 	    }
429 
430 	case CHIOGSTATUS:
431 		error = ch_usergetelemstatus(sc,
432 		    (struct changer_element_status_request *)data);
433 		break;
434 
435 	case CHIOSVOLTAG:
436 		error = ch_setvoltag(sc,
437 		    (struct changer_set_voltag_request *)data);
438 		break;
439 
440 	/* Implement prevent/allow? */
441 
442 	default:
443 		error = scsipi_do_ioctl(sc->sc_periph, dev, cmd, data,
444 		    flags, l);
445 		break;
446 	}
447 
448 	return (error);
449 }
450 
451 static int
452 chpoll(dev_t dev, int events, struct lwp *l)
453 {
454 	struct ch_softc *sc = device_lookup_private(&ch_cd, CHUNIT(dev));
455 	int revents;
456 
457 	revents = events & (POLLOUT | POLLWRNORM);
458 
459 	if ((events & (POLLIN | POLLRDNORM)) == 0)
460 		return (revents);
461 
462 	if (sc->sc_events == 0)
463 		revents |= events & (POLLIN | POLLRDNORM);
464 	else
465 		selrecord(l, &sc->sc_selq);
466 
467 	return (revents);
468 }
469 
470 static void
471 filt_chdetach(struct knote *kn)
472 {
473 	struct ch_softc *sc = kn->kn_hook;
474 
475 	SLIST_REMOVE(&sc->sc_selq.sel_klist, kn, knote, kn_selnext);
476 }
477 
478 static int
479 filt_chread(struct knote *kn, long hint)
480 {
481 	struct ch_softc *sc = kn->kn_hook;
482 
483 	if (sc->sc_events == 0)
484 		return (0);
485 	kn->kn_data = CHANGER_EVENT_SIZE;
486 	return (1);
487 }
488 
489 static const struct filterops chread_filtops =
490 	{ 1, NULL, filt_chdetach, filt_chread };
491 
492 static const struct filterops chwrite_filtops =
493 	{ 1, NULL, filt_chdetach, filt_seltrue };
494 
495 static int
496 chkqfilter(dev_t dev, struct knote *kn)
497 {
498 	struct ch_softc *sc = device_lookup_private(&ch_cd, CHUNIT(dev));
499 	struct klist *klist;
500 
501 	switch (kn->kn_filter) {
502 	case EVFILT_READ:
503 		klist = &sc->sc_selq.sel_klist;
504 		kn->kn_fop = &chread_filtops;
505 		break;
506 
507 	case EVFILT_WRITE:
508 		klist = &sc->sc_selq.sel_klist;
509 		kn->kn_fop = &chwrite_filtops;
510 		break;
511 
512 	default:
513 		return (EINVAL);
514 	}
515 
516 	kn->kn_hook = sc;
517 
518 	SLIST_INSERT_HEAD(klist, kn, kn_selnext);
519 
520 	return (0);
521 }
522 
523 static int
524 ch_interpret_sense(struct scsipi_xfer *xs)
525 {
526 	struct scsipi_periph *periph = xs->xs_periph;
527 	struct scsi_sense_data *sense = &xs->sense.scsi_sense;
528 	struct ch_softc *sc = device_private(periph->periph_dev);
529 	u_int16_t asc_ascq;
530 
531 	/*
532 	 * If the periph is already recovering, just do the
533 	 * normal error recovering.
534 	 */
535 	if (periph->periph_flags & PERIPH_RECOVERING)
536 		return (EJUSTRETURN);
537 
538 	/*
539 	 * If it isn't an extended or extended/deferred error, let
540 	 * the generic code handle it.
541 	 */
542 	if (SSD_RCODE(sense->response_code) != SSD_RCODE_CURRENT &&
543 	    SSD_RCODE(sense->response_code) != SSD_RCODE_DEFERRED)
544 		return (EJUSTRETURN);
545 
546 	/*
547 	 * We're only interested in condtions that
548 	 * indicate potential inventory violation.
549 	 *
550 	 * We use ASC/ASCQ codes for this.
551 	 */
552 
553 	asc_ascq = (((u_int16_t) sense->asc) << 8) |
554 	    sense->ascq;
555 
556 	switch (asc_ascq) {
557 	case 0x2800:
558 		/* "Not Ready To Ready Transition (Medium May Have Changed)" */
559 	case 0x2900:
560 		/* "Power On, Reset, or Bus Device Reset Occurred" */
561 		sc->sc_periph->periph_flags &= ~PERIPH_MEDIA_LOADED;
562 		/*
563 		 * Enqueue an Element-Status-Changed event, and wake up
564 		 * any processes waiting for them.
565 		 */
566 		if ((xs->xs_control & XS_CTL_IGNORE_MEDIA_CHANGE) == 0)
567 			ch_event(sc, CHEV_ELEMENT_STATUS_CHANGED);
568 		break;
569 	default:
570 		break;
571 	}
572 
573 	return (EJUSTRETURN);
574 }
575 
576 static void
577 ch_event(struct ch_softc *sc, u_int event)
578 {
579 
580 	sc->sc_events |= event;
581 	selnotify(&sc->sc_selq, 0, 0);
582 }
583 
584 static int
585 ch_move(struct ch_softc *sc, struct changer_move_request *cm)
586 {
587 	struct scsi_move_medium cmd;
588 	u_int16_t fromelem, toelem;
589 
590 	/*
591 	 * Check arguments.
592 	 */
593 	if ((cm->cm_fromtype > CHET_DT) || (cm->cm_totype > CHET_DT))
594 		return (EINVAL);
595 	if ((cm->cm_fromunit > (sc->sc_counts[cm->cm_fromtype] - 1)) ||
596 	    (cm->cm_tounit > (sc->sc_counts[cm->cm_totype] - 1)))
597 		return (ENODEV);
598 
599 	/*
600 	 * Check the request against the changer's capabilities.
601 	 */
602 	if ((sc->sc_movemask[cm->cm_fromtype] & (1 << cm->cm_totype)) == 0)
603 		return (ENODEV);
604 
605 	/*
606 	 * Calculate the source and destination elements.
607 	 */
608 	fromelem = sc->sc_firsts[cm->cm_fromtype] + cm->cm_fromunit;
609 	toelem = sc->sc_firsts[cm->cm_totype] + cm->cm_tounit;
610 
611 	/*
612 	 * Build the SCSI command.
613 	 */
614 	memset(&cmd, 0, sizeof(cmd));
615 	cmd.opcode = MOVE_MEDIUM;
616 	_lto2b(sc->sc_picker, cmd.tea);
617 	_lto2b(fromelem, cmd.src);
618 	_lto2b(toelem, cmd.dst);
619 	if (cm->cm_flags & CM_INVERT)
620 		cmd.flags |= MOVE_MEDIUM_INVERT;
621 
622 	/*
623 	 * Send command to changer.
624 	 */
625 	return (scsipi_command(sc->sc_periph, (void *)&cmd, sizeof(cmd), 0, 0,
626 	    CHRETRIES, CHTIMEOUT, NULL, 0));
627 }
628 
629 static int
630 ch_exchange(struct ch_softc *sc, struct changer_exchange_request *ce)
631 {
632 	struct scsi_exchange_medium cmd;
633 	u_int16_t src, dst1, dst2;
634 
635 	/*
636 	 * Check arguments.
637 	 */
638 	if ((ce->ce_srctype > CHET_DT) || (ce->ce_fdsttype > CHET_DT) ||
639 	    (ce->ce_sdsttype > CHET_DT))
640 		return (EINVAL);
641 	if ((ce->ce_srcunit > (sc->sc_counts[ce->ce_srctype] - 1)) ||
642 	    (ce->ce_fdstunit > (sc->sc_counts[ce->ce_fdsttype] - 1)) ||
643 	    (ce->ce_sdstunit > (sc->sc_counts[ce->ce_sdsttype] - 1)))
644 		return (ENODEV);
645 
646 	/*
647 	 * Check the request against the changer's capabilities.
648 	 */
649 	if (((sc->sc_exchangemask[ce->ce_srctype] &
650 	     (1 << ce->ce_fdsttype)) == 0) ||
651 	    ((sc->sc_exchangemask[ce->ce_fdsttype] &
652 	     (1 << ce->ce_sdsttype)) == 0))
653 		return (ENODEV);
654 
655 	/*
656 	 * Calculate the source and destination elements.
657 	 */
658 	src = sc->sc_firsts[ce->ce_srctype] + ce->ce_srcunit;
659 	dst1 = sc->sc_firsts[ce->ce_fdsttype] + ce->ce_fdstunit;
660 	dst2 = sc->sc_firsts[ce->ce_sdsttype] + ce->ce_sdstunit;
661 
662 	/*
663 	 * Build the SCSI command.
664 	 */
665 	memset(&cmd, 0, sizeof(cmd));
666 	cmd.opcode = EXCHANGE_MEDIUM;
667 	_lto2b(sc->sc_picker, cmd.tea);
668 	_lto2b(src, cmd.src);
669 	_lto2b(dst1, cmd.fdst);
670 	_lto2b(dst2, cmd.sdst);
671 	if (ce->ce_flags & CE_INVERT1)
672 		cmd.flags |= EXCHANGE_MEDIUM_INV1;
673 	if (ce->ce_flags & CE_INVERT2)
674 		cmd.flags |= EXCHANGE_MEDIUM_INV2;
675 
676 	/*
677 	 * Send command to changer.
678 	 */
679 	return (scsipi_command(sc->sc_periph, (void *)&cmd, sizeof(cmd), 0, 0,
680 	    CHRETRIES, CHTIMEOUT, NULL, 0));
681 }
682 
683 static int
684 ch_position(struct ch_softc *sc, struct changer_position_request *cp)
685 {
686 	struct scsi_position_to_element cmd;
687 	u_int16_t dst;
688 
689 	/*
690 	 * Check arguments.
691 	 */
692 	if (cp->cp_type > CHET_DT)
693 		return (EINVAL);
694 	if (cp->cp_unit > (sc->sc_counts[cp->cp_type] - 1))
695 		return (ENODEV);
696 
697 	/*
698 	 * Calculate the destination element.
699 	 */
700 	dst = sc->sc_firsts[cp->cp_type] + cp->cp_unit;
701 
702 	/*
703 	 * Build the SCSI command.
704 	 */
705 	memset(&cmd, 0, sizeof(cmd));
706 	cmd.opcode = POSITION_TO_ELEMENT;
707 	_lto2b(sc->sc_picker, cmd.tea);
708 	_lto2b(dst, cmd.dst);
709 	if (cp->cp_flags & CP_INVERT)
710 		cmd.flags |= POSITION_TO_ELEMENT_INVERT;
711 
712 	/*
713 	 * Send command to changer.
714 	 */
715 	return (scsipi_command(sc->sc_periph, (void *)&cmd, sizeof(cmd), 0, 0,
716 	    CHRETRIES, CHTIMEOUT, NULL, 0));
717 }
718 
719 /*
720  * Perform a READ ELEMENT STATUS on behalf of the user, and return to
721  * the user only the data the user is interested in.  This returns the
722  * old data format.
723  */
724 static int
725 ch_ousergetelemstatus(struct ch_softc *sc, int chet, u_int8_t *uptr)
726 {
727 	struct read_element_status_header *st_hdrp, st_hdr;
728 	struct read_element_status_page_header *pg_hdrp;
729 	struct read_element_status_descriptor *desc;
730 	size_t size, desclen;
731 	void *data;
732 	int avail, i, error = 0;
733 	u_int8_t user_data;
734 
735 	/*
736 	 * If there are no elements of the requested type in the changer,
737 	 * the request is invalid.
738 	 */
739 	if (sc->sc_counts[chet] == 0)
740 		return (EINVAL);
741 
742 	/*
743 	 * Do the request the user wants, but only read the status header.
744 	 * This will tell us the amount of storage we must allocate in
745 	 * order to read all data.
746 	 */
747 	error = ch_getelemstatus(sc, sc->sc_firsts[chet],
748 	    sc->sc_counts[chet], &st_hdr, sizeof(st_hdr), 0, 0);
749 	if (error)
750 		return (error);
751 
752 	size = sizeof(struct read_element_status_header) +
753 	    _3btol(st_hdr.nbytes);
754 
755 	/*
756 	 * We must have at least room for the status header and
757 	 * one page header (since we only ask for one element type
758 	 * at a time).
759 	 */
760 	if (size < (sizeof(struct read_element_status_header) +
761 	    sizeof(struct read_element_status_page_header)))
762 		return (EIO);
763 
764 	/*
765 	 * Allocate the storage and do the request again.
766 	 */
767 	data = malloc(size, M_DEVBUF, M_WAITOK);
768 	error = ch_getelemstatus(sc, sc->sc_firsts[chet],
769 	    sc->sc_counts[chet], data, size, 0, 0);
770 	if (error)
771 		goto done;
772 
773 	st_hdrp = (struct read_element_status_header *)data;
774 	pg_hdrp = (struct read_element_status_page_header *)((u_long)st_hdrp +
775 	    sizeof(struct read_element_status_header));
776 	desclen = _2btol(pg_hdrp->edl);
777 
778 	/*
779 	 * Fill in the user status array.
780 	 */
781 	avail = _2btol(st_hdrp->count);
782 
783 	if (avail != sc->sc_counts[chet])
784 		printf("%s: warning, READ ELEMENT STATUS avail != count\n",
785 		    device_xname(sc->sc_dev));
786 
787 	desc = (struct read_element_status_descriptor *)((u_long)data +
788 	    sizeof(struct read_element_status_header) +
789 	    sizeof(struct read_element_status_page_header));
790 	for (i = 0; i < avail; ++i) {
791 		user_data = desc->flags1;
792 		error = copyout(&user_data, &uptr[i], avail);
793 		if (error)
794 			break;
795 		desc = (struct read_element_status_descriptor *)((u_long)desc
796 		    + desclen);
797 	}
798 
799  done:
800 	if (data != NULL)
801 		free(data, M_DEVBUF);
802 	return (error);
803 }
804 
805 /*
806  * Perform a READ ELEMENT STATUS on behalf of the user.  This returns
807  * the new (more complete) data format.
808  */
809 static int
810 ch_usergetelemstatus(struct ch_softc *sc,
811     struct changer_element_status_request *cesr)
812 {
813 	struct scsipi_channel *chan = sc->sc_periph->periph_channel;
814 	struct scsipi_periph *dtperiph;
815 	struct read_element_status_header *st_hdrp, st_hdr;
816 	struct read_element_status_page_header *pg_hdrp;
817 	struct read_element_status_descriptor *desc;
818 	struct changer_volume_tag *avol, *pvol;
819 	size_t size, desclen, stddesclen, offset;
820 	int first, avail, i, error = 0;
821 	void *data;
822 	void *uvendptr;
823 	struct changer_element_status ces;
824 
825 	/*
826 	 * Check arguments.
827 	 */
828 	if (cesr->cesr_type > CHET_DT)
829 		return (EINVAL);
830 	if (sc->sc_counts[cesr->cesr_type] == 0)
831 		return (ENODEV);
832 	if (cesr->cesr_unit > (sc->sc_counts[cesr->cesr_type] - 1))
833 		return (ENODEV);
834 	if (cesr->cesr_count >
835 	    (sc->sc_counts[cesr->cesr_type] + cesr->cesr_unit))
836 		return (EINVAL);
837 
838 	/*
839 	 * Do the request the user wants, but only read the status header.
840 	 * This will tell us the amount of storage we must allocate
841 	 * in order to read all the data.
842 	 */
843 	error = ch_getelemstatus(sc, sc->sc_firsts[cesr->cesr_type] +
844 	    cesr->cesr_unit, cesr->cesr_count, &st_hdr, sizeof(st_hdr), 0,
845 	    cesr->cesr_flags);
846 	if (error)
847 		return (error);
848 
849 	size = sizeof(struct read_element_status_header) +
850 	    _3btol(st_hdr.nbytes);
851 
852 	/*
853 	 * We must have at least room for the status header and
854 	 * one page header (since we only ask for oen element type
855 	 * at a time).
856 	 */
857 	if (size < (sizeof(struct read_element_status_header) +
858 	    sizeof(struct read_element_status_page_header)))
859 		return (EIO);
860 
861 	/*
862 	 * Allocate the storage and do the request again.
863 	 */
864 	data = malloc(size, M_DEVBUF, M_WAITOK);
865 	error = ch_getelemstatus(sc, sc->sc_firsts[cesr->cesr_type] +
866 	    cesr->cesr_unit, cesr->cesr_count, data, size, 0,
867 	    cesr->cesr_flags);
868 	if (error)
869 		goto done;
870 
871 	st_hdrp = (struct read_element_status_header *)data;
872 	pg_hdrp = (struct read_element_status_page_header *)((u_long)st_hdrp +
873 	    sizeof(struct read_element_status_header));
874 	desclen = _2btol(pg_hdrp->edl);
875 
876 	/*
877 	 * Fill in the user status array.
878 	 */
879 	first = _2btol(st_hdrp->fear);
880 	if (first <  (sc->sc_firsts[cesr->cesr_type] + cesr->cesr_unit) ||
881 	    first >= (sc->sc_firsts[cesr->cesr_type] + cesr->cesr_unit +
882 		      cesr->cesr_count)) {
883 		error = EIO;
884 		goto done;
885 	}
886 	first -= sc->sc_firsts[cesr->cesr_type] + cesr->cesr_unit;
887 
888 	avail = _2btol(st_hdrp->count);
889 	if (avail <= 0 || avail > cesr->cesr_count) {
890 		error = EIO;
891 		goto done;
892 	}
893 
894 	offset = sizeof(struct read_element_status_header) +
895 		 sizeof(struct read_element_status_page_header);
896 
897 	for (i = 0; i < cesr->cesr_count; i++) {
898 		memset(&ces, 0, sizeof(ces));
899 		if (i < first || i >= (first + avail)) {
900 			error = copyout(&ces, &cesr->cesr_data[i],
901 			    sizeof(ces));
902 			if (error)
903 				goto done;
904 		}
905 
906 		desc = (struct read_element_status_descriptor *)
907 		    ((char *)data + offset);
908 		stddesclen = sizeof(struct read_element_status_descriptor);
909 		offset += desclen;
910 
911 		ces.ces_flags = CESTATUS_STATUS_VALID;
912 
913 		/*
914 		 * The SCSI flags conveniently map directly to the
915 		 * chio API flags.
916 		 */
917 		ces.ces_flags |= (desc->flags1 & 0x3f);
918 
919 		ces.ces_asc = desc->sense_code;
920 		ces.ces_ascq = desc->sense_qual;
921 
922 		/*
923 		 * For Data Transport elemenets, get the SCSI ID and LUN,
924 		 * and attempt to map them to a device name if they're
925 		 * on the same SCSI bus.
926 		 */
927 		if (desc->dt_scsi_flags & READ_ELEMENT_STATUS_DT_IDVALID) {
928 			ces.ces_target = desc->dt_scsi_addr;
929 			ces.ces_flags |= CESTATUS_TARGET_VALID;
930 		}
931 		if (desc->dt_scsi_flags & READ_ELEMENT_STATUS_DT_LUVALID) {
932 			ces.ces_lun = desc->dt_scsi_flags &
933 			    READ_ELEMENT_STATUS_DT_LUNMASK;
934 			ces.ces_flags |= CESTATUS_LUN_VALID;
935 		}
936 		if (desc->dt_scsi_flags & READ_ELEMENT_STATUS_DT_NOTBUS)
937 			ces.ces_flags |= CESTATUS_NOTBUS;
938 		else if ((ces.ces_flags &
939 			  (CESTATUS_TARGET_VALID|CESTATUS_LUN_VALID)) ==
940 			 (CESTATUS_TARGET_VALID|CESTATUS_LUN_VALID)) {
941 			if (ces.ces_target < chan->chan_ntargets &&
942 			    ces.ces_lun < chan->chan_nluns &&
943 			    (dtperiph = scsipi_lookup_periph(chan,
944 			     ces.ces_target, ces.ces_lun)) != NULL &&
945 			    dtperiph->periph_dev != NULL) {
946 				strlcpy(ces.ces_xname,
947 				    device_xname(dtperiph->periph_dev),
948 				    sizeof(ces.ces_xname));
949 				ces.ces_flags |= CESTATUS_XNAME_VALID;
950 			}
951 		}
952 
953 		if (desc->flags2 & READ_ELEMENT_STATUS_INVERT)
954 			ces.ces_flags |= CESTATUS_INVERTED;
955 
956 		if (desc->flags2 & READ_ELEMENT_STATUS_SVALID) {
957 			if (ch_map_element(sc, _2btol(desc->ssea),
958 			    &ces.ces_from_type, &ces.ces_from_unit))
959 				ces.ces_flags |= CESTATUS_FROM_VALID;
960 		}
961 
962 		/*
963 		 * Extract volume tag information.
964 		 */
965 		switch (pg_hdrp->flags &
966 		    (READ_ELEMENT_STATUS_PVOLTAG|READ_ELEMENT_STATUS_AVOLTAG)) {
967 		case (READ_ELEMENT_STATUS_PVOLTAG|READ_ELEMENT_STATUS_AVOLTAG):
968 			pvol = (struct changer_volume_tag *)(desc + 1);
969 			avol = pvol + 1;
970 			break;
971 
972 		case READ_ELEMENT_STATUS_PVOLTAG:
973 			pvol = (struct changer_volume_tag *)(desc + 1);
974 			avol = NULL;
975 			break;
976 
977 		case READ_ELEMENT_STATUS_AVOLTAG:
978 			pvol = NULL;
979 			avol = (struct changer_volume_tag *)(desc + 1);
980 			break;
981 
982 		default:
983 			avol = pvol = NULL;
984 			break;
985 		}
986 
987 		if (pvol != NULL) {
988 			ch_voltag_convert_in(pvol, &ces.ces_pvoltag);
989 			ces.ces_flags |= CESTATUS_PVOL_VALID;
990 			stddesclen += sizeof(struct changer_volume_tag);
991 		}
992 		if (avol != NULL) {
993 			ch_voltag_convert_in(avol, &ces.ces_avoltag);
994 			ces.ces_flags |= CESTATUS_AVOL_VALID;
995 			stddesclen += sizeof(struct changer_volume_tag);
996 		}
997 
998 		/*
999 		 * Compute vendor-specific length.  Note the 4 reserved
1000 		 * bytes between the volume tags and the vendor-specific
1001 		 * data.  Copy it out of the user wants it.
1002 		 */
1003 		stddesclen += 4;
1004 		if (desclen > stddesclen)
1005 			ces.ces_vendor_len = desclen - stddesclen;
1006 
1007 		if (ces.ces_vendor_len != 0 && cesr->cesr_vendor_data != NULL) {
1008 			error = copyin(&cesr->cesr_vendor_data[i], &uvendptr,
1009 			    sizeof(uvendptr));
1010 			if (error)
1011 				goto done;
1012 			error = copyout((void *)((u_long)desc + stddesclen),
1013 			    uvendptr, ces.ces_vendor_len);
1014 			if (error)
1015 				goto done;
1016 		}
1017 
1018 		/*
1019 		 * Now copy out the status descriptor we've constructed.
1020 		 */
1021 		error = copyout(&ces, &cesr->cesr_data[i], sizeof(ces));
1022 		if (error)
1023 			goto done;
1024 	}
1025 
1026  done:
1027 	if (data != NULL)
1028 		free(data, M_DEVBUF);
1029 	return (error);
1030 }
1031 
1032 static int
1033 ch_getelemstatus(struct ch_softc *sc, int first, int count, void *data,
1034     size_t datalen, int scsiflags, int flags)
1035 {
1036 	struct scsi_read_element_status cmd;
1037 
1038 	/*
1039 	 * Build SCSI command.
1040 	 */
1041 	memset(&cmd, 0, sizeof(cmd));
1042 	cmd.opcode = READ_ELEMENT_STATUS;
1043 	cmd.byte2 = ELEMENT_TYPE_ALL;
1044 	if (flags & CESR_VOLTAGS)
1045 		cmd.byte2 |= READ_ELEMENT_STATUS_VOLTAG;
1046 	_lto2b(first, cmd.sea);
1047 	_lto2b(count, cmd.count);
1048 	_lto3b(datalen, cmd.len);
1049 
1050 	/*
1051 	 * Send command to changer.
1052 	 */
1053 	return (scsipi_command(sc->sc_periph, (void *)&cmd, sizeof(cmd),
1054 	    (void *)data, datalen,
1055 	    CHRETRIES, CHTIMEOUT, NULL, scsiflags | XS_CTL_DATA_IN));
1056 }
1057 
1058 static int
1059 ch_setvoltag(struct ch_softc *sc, struct changer_set_voltag_request *csvr)
1060 {
1061 	struct scsi_send_volume_tag cmd;
1062 	struct changer_volume_tag voltag;
1063 	void *data = NULL;
1064 	size_t datalen = 0;
1065 	int error;
1066 	u_int16_t dst;
1067 
1068 	/*
1069 	 * Check arguments.
1070 	 */
1071 	if (csvr->csvr_type > CHET_DT)
1072 		return (EINVAL);
1073 	if (csvr->csvr_unit > (sc->sc_counts[csvr->csvr_type] - 1))
1074 		return (ENODEV);
1075 
1076 	dst = sc->sc_firsts[csvr->csvr_type] + csvr->csvr_unit;
1077 
1078 	/*
1079 	 * Build the SCSI command.
1080 	 */
1081 	memset(&cmd, 0, sizeof(cmd));
1082 	cmd.opcode = SEND_VOLUME_TAG;
1083 	_lto2b(dst, cmd.eaddr);
1084 
1085 #define	ALTERNATE	(csvr->csvr_flags & CSVR_ALTERNATE)
1086 
1087 	switch (csvr->csvr_flags & CSVR_MODE_MASK) {
1088 	case CSVR_MODE_SET:
1089 		cmd.sac = ALTERNATE ? SAC_ASSERT_ALT : SAC_ASSERT_PRIMARY;
1090 		break;
1091 
1092 	case CSVR_MODE_REPLACE:
1093 		cmd.sac = ALTERNATE ? SAC_REPLACE_ALT : SAC_REPLACE_PRIMARY;
1094 		break;
1095 
1096 	case CSVR_MODE_CLEAR:
1097 		cmd.sac = ALTERNATE ? SAC_UNDEFINED_ALT : SAC_UNDEFINED_PRIMARY;
1098 		break;
1099 
1100 	default:
1101 		return (EINVAL);
1102 	}
1103 
1104 #undef ALTERNATE
1105 
1106 	if (cmd.sac < SAC_UNDEFINED_PRIMARY) {
1107 		error = ch_voltag_convert_out(&csvr->csvr_voltag, &voltag);
1108 		if (error)
1109 			return (error);
1110 		data = &voltag;
1111 		datalen = sizeof(voltag);
1112 		_lto2b(datalen, cmd.length);
1113 	}
1114 
1115 	/*
1116 	 * Send command to changer.
1117 	 */
1118 	return (scsipi_command(sc->sc_periph, (void *)&cmd, sizeof(cmd),
1119 	    (void *)data, datalen, CHRETRIES, CHTIMEOUT, NULL,
1120 	    datalen ? XS_CTL_DATA_OUT : 0));
1121 }
1122 
1123 static int
1124 ch_ielem(struct ch_softc *sc)
1125 {
1126 	int tmo;
1127 	struct scsi_initialize_element_status cmd;
1128 
1129 	/*
1130 	 * Build SCSI command.
1131 	 */
1132 	memset(&cmd, 0, sizeof(cmd));
1133 	cmd.opcode = INITIALIZE_ELEMENT_STATUS;
1134 
1135 	/*
1136 	 * Send command to changer.
1137 	 *
1138 	 * The problem is, how long to allow for the command?
1139 	 * It can take a *really* long time, and also depends
1140 	 * on unknowable factors such as whether there are
1141 	 * *almost* readable labels on tapes that a barcode
1142 	 * reader is trying to decipher.
1143 	 *
1144 	 * I'm going to make this long enough to allow 5 minutes
1145 	 * per element plus an initial 10 minute wait.
1146 	 */
1147 	tmo =	sc->sc_counts[CHET_MT] +
1148 		sc->sc_counts[CHET_ST] +
1149 		sc->sc_counts[CHET_IE] +
1150 		sc->sc_counts[CHET_DT];
1151 	tmo *= 5 * 60 * 1000;
1152 	tmo += (10 * 60 * 1000);
1153 
1154 	return (scsipi_command(sc->sc_periph, (void *)&cmd, sizeof(cmd), 0, 0,
1155 	    CHRETRIES, tmo, NULL, XS_CTL_IGNORE_ILLEGAL_REQUEST));
1156 }
1157 
1158 /*
1159  * Ask the device about itself and fill in the parameters in our
1160  * softc.
1161  */
1162 static int
1163 ch_get_params(struct ch_softc *sc, int scsiflags)
1164 {
1165 	struct scsi_mode_sense_data {
1166 		struct scsi_mode_parameter_header_6 header;
1167 		union {
1168 			struct page_element_address_assignment ea;
1169 			struct page_transport_geometry_parameters tg;
1170 			struct page_device_capabilities cap;
1171 		} pages;
1172 	} sense_data;
1173 	int error, from;
1174 	u_int8_t *moves, *exchanges;
1175 
1176 	/*
1177 	 * Grab info from the element address assignment page.
1178 	 */
1179 	memset(&sense_data, 0, sizeof(sense_data));
1180 	error = scsipi_mode_sense(sc->sc_periph, SMS_DBD, 0x1d,
1181 	    &sense_data.header, sizeof(sense_data),
1182 	    scsiflags, CHRETRIES, 6000);
1183 	if (error) {
1184 		aprint_error_dev(sc->sc_dev, "could not sense element address page\n");
1185 		return (error);
1186 	}
1187 
1188 	sc->sc_firsts[CHET_MT] = _2btol(sense_data.pages.ea.mtea);
1189 	sc->sc_counts[CHET_MT] = _2btol(sense_data.pages.ea.nmte);
1190 	sc->sc_firsts[CHET_ST] = _2btol(sense_data.pages.ea.fsea);
1191 	sc->sc_counts[CHET_ST] = _2btol(sense_data.pages.ea.nse);
1192 	sc->sc_firsts[CHET_IE] = _2btol(sense_data.pages.ea.fieea);
1193 	sc->sc_counts[CHET_IE] = _2btol(sense_data.pages.ea.niee);
1194 	sc->sc_firsts[CHET_DT] = _2btol(sense_data.pages.ea.fdtea);
1195 	sc->sc_counts[CHET_DT] = _2btol(sense_data.pages.ea.ndte);
1196 
1197 	/* XXX ask for transport geometry page XXX */
1198 
1199 	/*
1200 	 * Grab info from the capabilities page.
1201 	 */
1202 	memset(&sense_data, 0, sizeof(sense_data));
1203 	/*
1204 	 * XXX: Note: not all changers can deal with disabled block descriptors
1205 	 */
1206 	error = scsipi_mode_sense(sc->sc_periph, SMS_DBD, 0x1f,
1207 	    &sense_data.header, sizeof(sense_data),
1208 	    scsiflags, CHRETRIES, 6000);
1209 	if (error) {
1210 		aprint_error_dev(sc->sc_dev, "could not sense capabilities page\n");
1211 		return (error);
1212 	}
1213 
1214 	memset(sc->sc_movemask, 0, sizeof(sc->sc_movemask));
1215 	memset(sc->sc_exchangemask, 0, sizeof(sc->sc_exchangemask));
1216 	moves = &sense_data.pages.cap.move_from_mt;
1217 	exchanges = &sense_data.pages.cap.exchange_with_mt;
1218 	for (from = CHET_MT; from <= CHET_DT; ++from) {
1219 		sc->sc_movemask[from] = moves[from];
1220 		sc->sc_exchangemask[from] = exchanges[from];
1221 	}
1222 
1223 #ifdef CH_AUTOMATIC_IELEM_POLICY
1224 	/*
1225 	 * If we need to do an Init-Element-Status,
1226 	 * do that now that we know what's in the changer.
1227 	 */
1228 	if ((scsiflags & XS_CTL_IGNORE_MEDIA_CHANGE) == 0) {
1229 		if ((sc->sc_periph->periph_flags & PERIPH_MEDIA_LOADED) == 0)
1230 			error = ch_ielem(sc);
1231 		if (error == 0)
1232 			sc->sc_periph->periph_flags |= PERIPH_MEDIA_LOADED;
1233 		else
1234 			sc->sc_periph->periph_flags &= ~PERIPH_MEDIA_LOADED;
1235 	}
1236 #endif
1237 	return (error);
1238 }
1239 
1240 static void
1241 ch_get_quirks(struct ch_softc *sc, struct scsipi_inquiry_pattern *inqbuf)
1242 {
1243 	const struct chquirk *match;
1244 	int priority;
1245 
1246 	sc->sc_settledelay = 0;
1247 
1248 	match = scsipi_inqmatch(inqbuf, chquirks,
1249 	    sizeof(chquirks) / sizeof(chquirks[0]),
1250 	    sizeof(chquirks[0]), &priority);
1251 	if (priority != 0)
1252 		sc->sc_settledelay = match->cq_settledelay;
1253 }
1254 
1255 static int
1256 ch_map_element(struct ch_softc *sc, u_int16_t elem, int *typep, int *unitp)
1257 {
1258 	int chet;
1259 
1260 	for (chet = CHET_MT; chet <= CHET_DT; chet++) {
1261 		if (elem >= sc->sc_firsts[chet] &&
1262 		    elem < (sc->sc_firsts[chet] + sc->sc_counts[chet])) {
1263 			*typep = chet;
1264 			*unitp = elem - sc->sc_firsts[chet];
1265 			return (1);
1266 		}
1267 	}
1268 	return (0);
1269 }
1270 
1271 static void
1272 ch_voltag_convert_in(const struct changer_volume_tag *sv,
1273     struct changer_voltag *cv)
1274 {
1275 	int i;
1276 
1277 	memset(cv, 0, sizeof(struct changer_voltag));
1278 
1279 	/*
1280 	 * Copy the volume tag string from the SCSI representation.
1281 	 * Per the SCSI-2 spec, we stop at the first blank character.
1282 	 */
1283 	for (i = 0; i < sizeof(sv->volid); i++) {
1284 		if (sv->volid[i] == ' ')
1285 			break;
1286 		cv->cv_tag[i] = sv->volid[i];
1287 	}
1288 	cv->cv_tag[i] = '\0';
1289 
1290 	cv->cv_serial = _2btol(sv->volseq);
1291 }
1292 
1293 static int
1294 ch_voltag_convert_out(const struct changer_voltag *cv,
1295     struct changer_volume_tag *sv)
1296 {
1297 	int i;
1298 
1299 	memset(sv, ' ', sizeof(struct changer_volume_tag));
1300 
1301 	for (i = 0; i < sizeof(sv->volid); i++) {
1302 		if (cv->cv_tag[i] == '\0')
1303 			break;
1304 		/*
1305 		 * Limit the character set to what is suggested in
1306 		 * the SCSI-2 spec.
1307 		 */
1308 		if ((cv->cv_tag[i] < '0' || cv->cv_tag[i] > '9') &&
1309 		    (cv->cv_tag[i] < 'A' || cv->cv_tag[i] > 'Z') &&
1310 		    (cv->cv_tag[i] != '_'))
1311 			return (EINVAL);
1312 		sv->volid[i] = cv->cv_tag[i];
1313 	}
1314 
1315 	_lto2b(cv->cv_serial, sv->volseq);
1316 
1317 	return (0);
1318 }
1319