xref: /netbsd-src/sys/dev/gpib/mt.c (revision 454af1c0e885cbba6b59706391f770d646303f8c)
1 /*	$NetBSD: mt.c,v 1.17 2009/03/14 15:36:17 dsl Exp $ */
2 
3 /*-
4  * Copyright (c) 1996-2003 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.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * Copyright (c) 1982, 1990, 1993
34  *	The Regents of the University of California.  All rights reserved.
35  *
36  * This code is derived from software contributed to Berkeley by
37  * the Systems Programming Group of the University of Utah Computer
38  * Science Department.
39  *
40  * Redistribution and use in source and binary forms, with or without
41  * modification, are permitted provided that the following conditions
42  * are met:
43  * 1. Redistributions of source code must retain the above copyright
44  *    notice, this list of conditions and the following disclaimer.
45  * 2. Redistributions in binary form must reproduce the above copyright
46  *    notice, this list of conditions and the following disclaimer in the
47  *    documentation and/or other materials provided with the distribution.
48  * 3. Neither the name of the University nor the names of its contributors
49  *    may be used to endorse or promote products derived from this software
50  *    without specific prior written permission.
51  *
52  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
53  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
54  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
55  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
56  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
57  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
58  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
59  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
60  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
61  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
62  * SUCH DAMAGE.
63  *
64  * from: Utah $Hdr: rd.c 1.44 92/12/26$
65  *
66  *	@(#)rd.c	8.2 (Berkeley) 5/19/94
67  */
68 
69 /*
70  * Copyright (c) 1988 University of Utah.
71  *
72  * This code is derived from software contributed to Berkeley by
73  * the Systems Programming Group of the University of Utah Computer
74  * Science Department.
75  *
76  * Redistribution and use in source and binary forms, with or without
77  * modification, are permitted provided that the following conditions
78  * are met:
79  * 1. Redistributions of source code must retain the above copyright
80  *    notice, this list of conditions and the following disclaimer.
81  * 2. Redistributions in binary form must reproduce the above copyright
82  *    notice, this list of conditions and the following disclaimer in the
83  *    documentation and/or other materials provided with the distribution.
84  * 3. All advertising materials mentioning features or use of this software
85  *    must display the following acknowledgement:
86  *	This product includes software developed by the University of
87  *	California, Berkeley and its contributors.
88  * 4. Neither the name of the University nor the names of its contributors
89  *    may be used to endorse or promote products derived from this software
90  *    without specific prior written permission.
91  *
92  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
93  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
94  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
95  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
96  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
97  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
98  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
99  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
100  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
101  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
102  * SUCH DAMAGE.
103  *
104  * from: Utah $Hdr: rd.c 1.44 92/12/26$
105  *
106  *	@(#)rd.c	8.2 (Berkeley) 5/19/94
107  */
108 
109 /*
110  * Magnetic tape driver (HP7974a, HP7978a/b, HP7979a, HP7980a, HP7980xc)
111  * Original version contributed by Mt. Xinu.
112  * Modified for 4.4BSD by Mark Davies and Andrew Vignaux, Department of
113  * Computer Science, Victoria University of Wellington
114  */
115 
116 #include <sys/cdefs.h>
117 __KERNEL_RCSID(0, "$NetBSD: mt.c,v 1.17 2009/03/14 15:36:17 dsl Exp $");
118 
119 #include <sys/param.h>
120 #include <sys/systm.h>
121 #include <sys/callout.h>
122 #include <sys/buf.h>
123 #include <sys/bufq.h>
124 #include <sys/ioctl.h>
125 #include <sys/mtio.h>
126 #include <sys/file.h>
127 #include <sys/proc.h>
128 #include <sys/tty.h>
129 #include <sys/kernel.h>
130 #include <sys/tprintf.h>
131 #include <sys/device.h>
132 #include <sys/conf.h>
133 
134 #include <dev/gpib/gpibvar.h>
135 #include <dev/gpib/cs80busvar.h>
136 
137 #include <dev/gpib/mtreg.h>
138 
139 #ifdef DEBUG
140 int	mtdebug = 0;
141 #define MDB_ANY		0xff
142 #define MDB_FOLLOW	0x01
143 #define	DPRINTF(mask, str)	if (mtdebug & (mask)) printf str
144 #else
145 #define	DPRINTF(mask, str)	/* nothing */
146 #endif
147 
148 struct	mt_softc {
149 	struct	device sc_dev;
150 
151 	gpib_chipset_tag_t sc_ic;
152 	gpib_handle_t sc_hdl;
153 
154 	int	sc_slave;	/* GPIB slave address (0-6) */
155 	short	sc_flags;	/* see below */
156 	u_char	sc_lastdsj;	/* place for DSJ in mtreaddsj() */
157 	u_char	sc_lastecmd;	/* place for End Command in mtreaddsj() */
158 	short	sc_recvtimeo;	/* count of gpibsend timeouts to prevent hang */
159 	short	sc_statindex;	/* index for next sc_stat when MTF_STATTIMEO */
160 	struct	mt_stat sc_stat;/* status bytes last read from device */
161 	short	sc_density;	/* current density of tape (mtio.h format) */
162 	short	sc_type;	/* tape drive model (hardware IDs) */
163 	tpr_t	sc_ttyp;
164 	struct bufq_state *sc_tab;/* buf queue */
165 	int	sc_active;
166 	struct buf sc_bufstore;	/* XXX buffer storage */
167 
168 	struct	callout sc_start_ch;
169 	struct	callout sc_intr_ch;
170 };
171 
172 #define	MTUNIT(x)	(minor(x) & 0x03)
173 
174 #define B_CMD		B_DEVPRIVATE	/* command buf instead of data */
175 #define	b_cmd		b_blkno		/* blkno holds cmd when B_CMD */
176 
177 int	mtmatch(struct device *, struct cfdata *, void *);
178 void	mtattach(struct device *, struct device *, void *);
179 
180 CFATTACH_DECL(mt, sizeof(struct mt_softc),
181 	mtmatch, mtattach, NULL, NULL);
182 
183 int	mtlookup(int, int, int);
184 void	mtustart(struct mt_softc *);
185 int	mtreaddsj(struct mt_softc *, int);
186 int	mtcommand(dev_t, int, int);
187 
188 void	mtintr_callout(void *);
189 void	mtstart_callout(void *);
190 
191 void	mtcallback(void *, int);
192 void	mtstart(struct mt_softc *);
193 void	mtintr(struct mt_softc  *);
194 
195 dev_type_open(mtopen);
196 dev_type_close(mtclose);
197 dev_type_read(mtread);
198 dev_type_write(mtwrite);
199 dev_type_ioctl(mtioctl);
200 dev_type_strategy(mtstrategy);
201 
202 const struct bdevsw mt_bdevsw = {
203 	mtopen, mtclose, mtstrategy, mtioctl, nodump, nosize, D_TAPE
204 };
205 
206 const struct cdevsw mt_cdevsw = {
207 	mtopen, mtclose, mtread, mtwrite, mtioctl,
208 	nostop, notty, nopoll, nommap, nokqfilter, D_TAPE
209 };
210 
211 
212 extern struct cfdriver mt_cd;
213 
214 struct	mtinfo {
215 	u_short	hwid;
216 	const char	*desc;
217 } mtinfo[] = {
218 	{ MT7978ID,	"7978"	},
219 	{ MT7979AID,	"7979A"	},
220 	{ MT7980ID,	"7980"	},
221 	{ MT7974AID,	"7974A"	},
222 };
223 int	nmtinfo = sizeof(mtinfo) / sizeof(mtinfo[0]);
224 
225 
226 int
227 mtlookup(int id, int slave, int punit)
228 {
229 	int i;
230 
231 	for (i = 0; i < nmtinfo; i++)
232 		if (mtinfo[i].hwid == id)
233 			break;
234 	if (i == nmtinfo)
235 		return (-1);
236 	return (0);
237 }
238 
239 int
240 mtmatch(struct device *parent, struct cfdata *match, void *aux)
241 {
242 	struct cs80bus_attach_args *ca = aux;
243 
244 	ca->ca_punit = 0;
245 	return (mtlookup(ca->ca_id, ca->ca_slave, ca->ca_punit) == 0);
246 }
247 
248 void
249 mtattach(parent, self, aux)
250 	struct device *parent, *self;
251 	void *aux;
252 {
253 	struct mt_softc *sc = device_private(self);
254 	struct cs80bus_attach_args *ca = aux;
255 	int type;
256 
257 	sc->sc_ic = ca->ca_ic;
258 	sc->sc_slave = ca->ca_slave;
259 
260 	if ((type = mtlookup(ca->ca_id, ca->ca_slave, ca->ca_punit)) < 0)
261 		return;
262 
263 	printf(": %s tape\n", mtinfo[type].desc);
264 
265 	sc->sc_type = type;
266 	sc->sc_flags = MTF_EXISTS;
267 
268 	bufq_alloc(&sc->sc_tab, "fcfs", 0);
269 	callout_init(&sc->sc_start_ch, 0);
270 	callout_init(&sc->sc_intr_ch, 0);
271 
272 	if (gpibregister(sc->sc_ic, sc->sc_slave, mtcallback, sc,
273 	    &sc->sc_hdl)) {
274 		aprint_error_dev(&sc->sc_dev, "can't register callback\n");
275 		return;
276 	}
277 }
278 
279 /*
280  * Perform a read of "Device Status Jump" register and update the
281  * status if necessary.  If status is read, the given "ecmd" is also
282  * performed, unless "ecmd" is zero.  Returns DSJ value, -1 on failure
283  * and -2 on "temporary" failure.
284  */
285 int
286 mtreaddsj(struct mt_softc *sc, int ecmd)
287 {
288 	int retval;
289 
290 	if (sc->sc_flags & MTF_STATTIMEO)
291 		goto getstats;
292 	retval = gpibrecv(sc->sc_ic,
293 	    (sc->sc_flags & MTF_DSJTIMEO) ? -1 : sc->sc_slave,
294 	    MTT_DSJ, &(sc->sc_lastdsj), 1);
295 	sc->sc_flags &= ~MTF_DSJTIMEO;
296 	if (retval != 1) {
297 		DPRINTF(MDB_ANY, ("%s can't gpibrecv DSJ",
298 		    device_xname(&sc->sc_dev)));
299 		if (sc->sc_recvtimeo == 0)
300 			sc->sc_recvtimeo = hz;
301 		if (--sc->sc_recvtimeo == 0)
302 			return (-1);
303 		if (retval == 0)
304 			sc->sc_flags |= MTF_DSJTIMEO;
305 		return (-2);
306 	}
307 	sc->sc_recvtimeo = 0;
308 	sc->sc_statindex = 0;
309 	DPRINTF(MDB_ANY, ("%s readdsj: 0x%x", device_xname(&sc->sc_dev),
310 	    sc->sc_lastdsj));
311 	sc->sc_lastecmd = ecmd;
312 	switch (sc->sc_lastdsj) {
313 	    case 0:
314 		if (ecmd & MTE_DSJ_FORCE)
315 			break;
316 		return (0);
317 
318 	    case 2:
319 		sc->sc_lastecmd = MTE_COMPLETE;
320 	    case 1:
321 		break;
322 
323 	    default:
324 		printf("%s readdsj: DSJ 0x%x\n", device_xname(&sc->sc_dev),
325 		    sc->sc_lastdsj);
326 		return (-1);
327 	}
328 
329 getstats:
330 	retval = gpibrecv(sc->sc_ic,
331 	    (sc->sc_flags & MTF_STATCONT) ? -1 : sc->sc_slave, MTT_STAT,
332 	     ((char *)&(sc->sc_stat)) + sc->sc_statindex,
333 	    sizeof(sc->sc_stat) - sc->sc_statindex);
334 	sc->sc_flags &= ~(MTF_STATTIMEO | MTF_STATCONT);
335 	if (retval != sizeof(sc->sc_stat) - sc->sc_statindex) {
336 		if (sc->sc_recvtimeo == 0)
337 			sc->sc_recvtimeo = hz;
338 		if (--sc->sc_recvtimeo != 0) {
339 			if (retval >= 0) {
340 				sc->sc_statindex += retval;
341 				sc->sc_flags |= MTF_STATCONT;
342 			}
343 			sc->sc_flags |= MTF_STATTIMEO;
344 			return (-2);
345 		}
346 		printf("%s readdsj: can't read status", device_xname(&sc->sc_dev));
347 		return (-1);
348 	}
349 	sc->sc_recvtimeo = 0;
350 	sc->sc_statindex = 0;
351 	DPRINTF(MDB_ANY, ("%s readdsj: status is %x %x %x %x %x %x",
352 	    device_xname(&sc->sc_dev),
353 	    sc->sc_stat1, sc->sc_stat2, sc->sc_stat3,
354 	    sc->sc_stat4, sc->sc_stat5, sc->sc_stat6));
355 	if (sc->sc_lastecmd)
356 		(void) gpibsend(sc->sc_ic, sc->sc_slave,
357 		    MTL_ECMD, &(sc->sc_lastecmd), 1);
358 	return ((int) sc->sc_lastdsj);
359 }
360 
361 int
362 mtopen(dev_t dev, int flag, int mode, struct lwp *l)
363 {
364 	struct mt_softc *sc;
365 	int req_den;
366 	int error;
367 
368 	sc = device_lookup_private(&mt_cd, MTUNIT(dev));
369 	if (sc == NULL || (sc->sc_flags & MTF_EXISTS) == 0)
370 		return (ENXIO);
371 
372 	if (sc->sc_flags & MTF_OPEN)
373 		return (EBUSY);
374 
375 	DPRINTF(MDB_ANY, ("%s open: flags 0x%x", device_xname(&sc->sc_dev),
376 	    sc->sc_flags));
377 
378 	sc->sc_flags |= MTF_OPEN;
379 	sc->sc_ttyp = tprintf_open(l->l_proc);
380 	if ((sc->sc_flags & MTF_ALIVE) == 0) {
381 		error = mtcommand(dev, MTRESET, 0);
382 		if (error != 0 || (sc->sc_flags & MTF_ALIVE) == 0)
383 			goto errout;
384 		if ((sc->sc_stat1 & (SR1_BOT | SR1_ONLINE)) == SR1_ONLINE)
385 			(void) mtcommand(dev, MTREW, 0);
386 	}
387 	for (;;) {
388 		if ((error = mtcommand(dev, MTNOP, 0)) != 0)
389 			goto errout;
390 		if (!(sc->sc_flags & MTF_REW))
391 			break;
392 		if (tsleep((void *) &lbolt, PCATCH | (PZERO + 1),
393 		    "mt", 0) != 0) {
394 			error = EINTR;
395 			goto errout;
396 		}
397 	}
398 	if ((flag & FWRITE) && (sc->sc_stat1 & SR1_RO)) {
399 		error = EROFS;
400 		goto errout;
401 	}
402 	if (!(sc->sc_stat1 & SR1_ONLINE)) {
403 		uprintf("%s: not online\n", device_xname(&sc->sc_dev));
404 		error = EIO;
405 		goto errout;
406 	}
407 	/*
408 	 * Select density:
409 	 *  - find out what density the drive is set to
410 	 *	(i.e. the density of the current tape)
411 	 *  - if we are going to write
412 	 *    - if we're not at the beginning of the tape
413 	 *      - complain if we want to change densities
414 	 *    - otherwise, select the mtcommand to set the density
415 	 *
416 	 * If the drive doesn't support it then don't change the recorded
417 	 * density.
418 	 *
419 	 * The original MOREbsd code had these additional conditions
420 	 * for the mid-tape change
421 	 *
422 	 *	req_den != T_BADBPI &&
423 	 *	sc->sc_density != T_6250BPI
424 	 *
425 	 * which suggests that it would be possible to write multiple
426 	 * densities if req_den == T_BAD_BPI or the current tape
427 	 * density was 6250.  Testing of our 7980 suggests that the
428 	 * device cannot change densities mid-tape.
429 	 *
430 	 * ajv@comp.vuw.ac.nz
431 	 */
432 	sc->sc_density = (sc->sc_stat2 & SR2_6250) ? T_6250BPI : (
433 			 (sc->sc_stat3 & SR3_1600) ? T_1600BPI : (
434 			 (sc->sc_stat3 & SR3_800) ? T_800BPI : -1));
435 	req_den = (dev & T_DENSEL);
436 
437 	if (flag & FWRITE) {
438 		if (!(sc->sc_stat1 & SR1_BOT)) {
439 			if (sc->sc_density != req_den) {
440 				uprintf("%s: can't change density mid-tape\n",
441 				    device_xname(&sc->sc_dev));
442 				error = EIO;
443 				goto errout;
444 			}
445 		}
446 		else {
447 			int mtset_density =
448 			    (req_den == T_800BPI  ? MTSET800BPI : (
449 			     req_den == T_1600BPI ? MTSET1600BPI : (
450 			     req_den == T_6250BPI ? MTSET6250BPI : (
451 			     sc->sc_type == MT7980ID
452 						  ? MTSET6250DC
453 						  : MTSET6250BPI))));
454 			if (mtcommand(dev, mtset_density, 0) == 0)
455 				sc->sc_density = req_den;
456 		}
457 	}
458 	return (0);
459 errout:
460 	sc->sc_flags &= ~MTF_OPEN;
461 	return (error);
462 }
463 
464 int
465 mtclose(dev_t dev, int flag, int fmt, struct lwp *l)
466 {
467 	struct mt_softc *sc;
468 
469 	sc = device_lookup_private(&mt_cd, MTUNIT(dev));
470 	if (sc == NULL)
471 		return (ENXIO);
472 
473 	if (sc->sc_flags & MTF_WRT) {
474 		(void) mtcommand(dev, MTWEOF, 2);
475 		(void) mtcommand(dev, MTBSF, 0);
476 	}
477 	if ((minor(dev) & T_NOREWIND) == 0)
478 		(void) mtcommand(dev, MTREW, 0);
479 	sc->sc_flags &= ~MTF_OPEN;
480 	tprintf_close(sc->sc_ttyp);
481 	return (0);
482 }
483 
484 int
485 mtcommand(dev_t dev, int cmd, int cnt)
486 {
487 	struct mt_softc *sc;
488 	struct buf *bp;
489 	int error = 0;
490 
491 	sc = device_lookup_private(&mt_cd, MTUNIT(dev));
492 	bp = &sc->sc_bufstore;
493 
494 	if (bp->b_cflags & BC_BUSY)
495 		return (EBUSY);
496 
497 	bp->b_cmd = cmd;
498 	bp->b_dev = dev;
499 	bp->b_objlock = &buffer_lock;
500 	do {
501 		bp->b_cflags = BC_BUSY;
502 		bp->b_flags = B_CMD;
503 		bp->b_oflags = 0;
504 		mtstrategy(bp);
505 		biowait(bp);
506 		if (bp->b_error != 0) {
507 			error = (int) (unsigned) bp->b_error;
508 			break;
509 		}
510 	} while (--cnt > 0);
511 #if 0
512 	bp->b_cflags = 0 /*&= ~BC_BUSY*/;
513 #else
514 	bp->b_cflags &= ~BC_BUSY;
515 #endif
516 	return (error);
517 }
518 
519 /*
520  * Only thing to check here is for legal record lengths (writes only).
521  */
522 void
523 mtstrategy(struct buf *bp)
524 {
525 	struct mt_softc *sc;
526 	int s;
527 
528 	sc = device_lookup_private(&mt_cd, MTUNIT(bp->b_dev));
529 
530 	DPRINTF(MDB_ANY, ("%s strategy", device_xname(&sc->sc_dev)));
531 
532 	if ((bp->b_flags & (B_CMD | B_READ)) == 0) {
533 #define WRITE_BITS_IGNORED	8
534 #if 0
535 		if (bp->b_bcount & ((1 << WRITE_BITS_IGNORED) - 1)) {
536 			tprintf(sc->sc_ttyp,
537 				"%s: write record must be multiple of %d\n",
538 				device_xname(&sc->sc_dev), 1 << WRITE_BITS_IGNORED);
539 			goto error;
540 		}
541 #endif
542 		s = 16 * 1024;
543 		if (sc->sc_stat2 & SR2_LONGREC) {
544 			switch (sc->sc_density) {
545 			    case T_1600BPI:
546 				s = 32 * 1024;
547 				break;
548 
549 			    case T_6250BPI:
550 			    case T_BADBPI:
551 				s = 60 * 1024;
552 				break;
553 			}
554 		}
555 		if (bp->b_bcount > s) {
556 			tprintf(sc->sc_ttyp,
557 				"%s: write record (%d) too big: limit (%d)\n",
558 				device_xname(&sc->sc_dev), bp->b_bcount, s);
559 #if 0 /* XXX see above */
560 	    error:
561 #endif
562 			bp->b_error = EIO;
563 			biodone(bp);
564 			return;
565 		}
566 	}
567 	s = splbio();
568 	bufq_put(sc->sc_tab, bp);
569 	if (sc->sc_active == 0) {
570 		sc->sc_active = 1;
571 		mtustart(sc);
572 	}
573 	splx(s);
574 }
575 
576 void
577 mtustart(struct mt_softc *sc)
578 {
579 
580 	DPRINTF(MDB_ANY, ("%s ustart", device_xname(&sc->sc_dev)));
581 	if (gpibrequest(sc->sc_ic, sc->sc_hdl))
582 		mtstart(sc);
583 }
584 
585 void
586 mtcallback(void *v, int action)
587 {
588 	struct mt_softc *sc = v;
589 
590 	DPRINTF(MDB_FOLLOW, ("mtcallback: v=%p, action=%d\n", v, action));
591 
592 	switch (action) {
593 	case GPIBCBF_START:
594 		mtstart(sc);
595 		break;
596 	case GPIBCBF_INTR:
597 		mtintr(sc);
598 		break;
599 #ifdef DEBUG
600 	default:
601 		printf("mtcallback: unknown action %d\n", action);
602 		break;
603 #endif
604 	}
605 }
606 
607 void
608 mtintr_callout(void *arg)
609 {
610 	struct mt_softc *sc = arg;
611 	int s = splbio();
612 
613 	gpibppclear(sc->sc_ic);
614 	mtintr(sc);
615 	splx(s);
616 }
617 
618 void
619 mtstart_callout(void *arg)
620 {
621 	int s = splbio();
622 
623 	mtstart((struct mt_softc *)arg);
624 	splx(s);
625 }
626 
627 void
628 mtstart(struct mt_softc *sc)
629 {
630 	struct buf *bp;
631 	short	cmdcount = 1;
632 	u_char	cmdbuf[2];
633 
634 	DPRINTF(MDB_ANY, ("%s start", device_xname(&sc->sc_dev)));
635 	sc->sc_flags &= ~MTF_WRT;
636 	bp = bufq_peek(sc->sc_tab);
637 	if ((sc->sc_flags & MTF_ALIVE) == 0 &&
638 	    ((bp->b_flags & B_CMD) == 0 || bp->b_cmd != MTRESET))
639 		goto fatalerror;
640 
641 	if (sc->sc_flags & MTF_REW) {
642 		if (!gpibpptest(sc->sc_ic, sc->sc_slave))
643 			goto stillrew;
644 		switch (mtreaddsj(sc, MTE_DSJ_FORCE|MTE_COMPLETE|MTE_IDLE)) {
645 		    case 0:
646 		    case 1:
647 		stillrew:
648 			if ((sc->sc_stat1 & SR1_BOT) ||
649 			    !(sc->sc_stat1 & SR1_ONLINE)) {
650 				sc->sc_flags &= ~MTF_REW;
651 				break;
652 			}
653 		    case -2:
654 			/*
655 			 * -2 means "timeout" reading DSJ, which is probably
656 			 * temporary.  This is considered OK when doing a NOP,
657 			 * but not otherwise.
658 			 */
659 			if (sc->sc_flags & (MTF_DSJTIMEO | MTF_STATTIMEO)) {
660 				callout_reset(&sc->sc_start_ch, hz >> 5,
661 				    mtstart_callout, sc);
662 				return;
663 			}
664 		    case 2:
665 			if (bp->b_cmd != MTNOP || !(bp->b_flags & B_CMD)) {
666 				bp->b_error = EBUSY;
667 				goto done;
668 			}
669 			goto done;
670 
671 		    default:
672 			goto fatalerror;
673 		}
674 	}
675 	if (bp->b_flags & B_CMD) {
676 		if (sc->sc_flags & MTF_PASTEOT) {
677 			switch(bp->b_cmd) {
678 			    case MTFSF:
679 			    case MTWEOF:
680 			    case MTFSR:
681 				bp->b_error = ENOSPC;
682 				goto done;
683 
684 			    case MTBSF:
685 			    case MTOFFL:
686 			    case MTBSR:
687 			    case MTREW:
688 				sc->sc_flags &= ~(MTF_PASTEOT | MTF_ATEOT);
689 				break;
690 			}
691 		}
692 		switch(bp->b_cmd) {
693 		    case MTFSF:
694 			if (sc->sc_flags & MTF_HITEOF)
695 				goto done;
696 			cmdbuf[0] = MTTC_FSF;
697 			break;
698 
699 		    case MTBSF:
700 			if (sc->sc_flags & MTF_HITBOF)
701 				goto done;
702 			cmdbuf[0] = MTTC_BSF;
703 			break;
704 
705 		    case MTOFFL:
706 			sc->sc_flags |= MTF_REW;
707 			cmdbuf[0] = MTTC_REWOFF;
708 			break;
709 
710 		    case MTWEOF:
711 			cmdbuf[0] = MTTC_WFM;
712 			break;
713 
714 		    case MTBSR:
715 			cmdbuf[0] = MTTC_BSR;
716 			break;
717 
718 		    case MTFSR:
719 			cmdbuf[0] = MTTC_FSR;
720 			break;
721 
722 		    case MTREW:
723 			sc->sc_flags |= MTF_REW;
724 			cmdbuf[0] = MTTC_REW;
725 			break;
726 
727 		    case MTNOP:
728 			/*
729 			 * NOP is supposed to set status bits.
730 			 * Force readdsj to do it.
731 			 */
732 			switch (mtreaddsj(sc,
733 			  MTE_DSJ_FORCE | MTE_COMPLETE | MTE_IDLE)) {
734 			    default:
735 				goto done;
736 
737 			    case -1:
738 				/*
739 				 * If this fails, perform a device clear
740 				 * to fix any protocol problems and (most
741 				 * likely) get the status.
742 				 */
743 				bp->b_cmd = MTRESET;
744 				break;
745 
746 			    case -2:
747 				callout_reset(&sc->sc_start_ch, hz >> 5,
748 				    mtstart_callout, sc);
749 				return;
750 			}
751 
752 		    case MTRESET:
753 			/*
754 			 * 1) selected device clear (send with "-2" secondary)
755 			 * 2) set timeout, then wait for "service request"
756 			 * 3) interrupt will read DSJ (and END COMPLETE-IDLE)
757 			 */
758 			if (gpibsend(sc->sc_ic, sc->sc_slave, -2, NULL, 0)){
759 				aprint_error_dev(&sc->sc_dev, "can't reset");
760 				goto fatalerror;
761 			}
762 			callout_reset(&sc->sc_intr_ch, 4*hz, mtintr_callout,
763 			    sc);
764 			gpibawait(sc->sc_ic);
765 			return;
766 
767 		    case MTSET800BPI:
768 			cmdbuf[0] = MTTC_800;
769 			break;
770 
771 		    case MTSET1600BPI:
772 			cmdbuf[0] = MTTC_1600;
773 			break;
774 
775 		    case MTSET6250BPI:
776 			cmdbuf[0] = MTTC_6250;
777 			break;
778 
779 		    case MTSET6250DC:
780 			cmdbuf[0] = MTTC_DC6250;
781 			break;
782 		}
783 	} else {
784 		if (sc->sc_flags & MTF_PASTEOT) {
785 			bp->b_error = ENOSPC;
786 			goto done;
787 		}
788 		if (bp->b_flags & B_READ) {
789 			sc->sc_flags |= MTF_IO;
790 			cmdbuf[0] = MTTC_READ;
791 		} else {
792 			sc->sc_flags |= MTF_WRT | MTF_IO;
793 			cmdbuf[0] = MTTC_WRITE;
794 			cmdbuf[1] = (bp->b_bcount +((1 << WRITE_BITS_IGNORED) - 1)) >> WRITE_BITS_IGNORED;
795 			cmdcount = 2;
796 		}
797 	}
798 	if (gpibsend(sc->sc_ic, sc->sc_slave, MTL_TCMD, cmdbuf, cmdcount)
799 	    == cmdcount) {
800 		if (sc->sc_flags & MTF_REW)
801 			goto done;
802 		gpibawait(sc->sc_ic);
803 		return;
804 	}
805 fatalerror:
806 	/*
807 	 * If anything fails, the drive is probably hosed, so mark it not
808 	 * "ALIVE" (but it EXISTS and is OPEN or we wouldn't be here, and
809 	 * if, last we heard, it was REWinding, remember that).
810 	 */
811 	sc->sc_flags &= MTF_EXISTS | MTF_OPEN | MTF_REW;
812 	bp->b_error = EIO;
813 done:
814 	sc->sc_flags &= ~(MTF_HITEOF | MTF_HITBOF);
815 	(void)bufq_get(sc->sc_tab);
816 	biodone(bp);
817 	gpibrelease(sc->sc_ic, sc->sc_hdl);
818 	if ((bp = bufq_peek(sc->sc_tab)) == NULL)
819 		sc->sc_active = 0;
820 	else
821 		mtustart(sc);
822 }
823 
824 void
825 mtintr(struct mt_softc *sc)
826 {
827 	struct buf *bp;
828 	int slave, dir, i;
829 	u_char cmdbuf[4];
830 
831 	slave = sc->sc_slave;
832 
833 	bp = bufq_peek(sc->sc_tab);
834 	if (bp == NULL) {
835 		printf("%s intr: bp == NULL", device_xname(&sc->sc_dev));
836 		return;
837 	}
838 
839 	DPRINTF(MDB_ANY, ("%s intr", device_xname(&sc->sc_dev)));
840 
841 	/*
842 	 * Some operation completed.  Read status bytes and report errors.
843 	 * Clear EOF flags here `cause they're set once on specific conditions
844 	 * below when a command succeeds.
845 	 * A DSJ of 2 always means keep waiting.  If the command was READ
846 	 * (and we're in data DMA phase) stop data transfer first.
847 	 */
848 	sc->sc_flags &= ~(MTF_HITEOF | MTF_HITBOF);
849 	if ((bp->b_flags & (B_CMD|B_READ)) == B_READ &&
850 	    !(sc->sc_flags & (MTF_IO | MTF_STATTIMEO | MTF_DSJTIMEO))){
851 		cmdbuf[0] = MTE_STOP;
852 		(void) gpibsend(sc->sc_ic, slave, MTL_ECMD,cmdbuf,1);
853 	}
854 	switch (mtreaddsj(sc, 0)) {
855 	    case 0:
856 		break;
857 
858 	    case 1:
859 		/*
860 		 * If we're in the middle of a READ/WRITE and have yet to
861 		 * start the data transfer, a DSJ of one should terminate it.
862 		 */
863 		sc->sc_flags &= ~MTF_IO;
864 		break;
865 
866 	    case 2:
867 		(void) gpibawait(sc->sc_ic);
868 		return;
869 
870 	    case -2:
871 		/*
872 		 * -2 means that the drive failed to respond quickly enough
873 		 * to the request for DSJ.  It's probably just "busy" figuring
874 		 * it out and will know in a little bit...
875 		 */
876 		callout_reset(&sc->sc_intr_ch, hz >> 5, mtintr_callout, sc);
877 		return;
878 
879 	    default:
880 		printf("%s intr: can't get drive stat", device_xname(&sc->sc_dev));
881 		goto error;
882 	}
883 	if (sc->sc_stat1 & (SR1_ERR | SR1_REJECT)) {
884 		i = sc->sc_stat4 & SR4_ERCLMASK;
885 		printf("%s: %s error, retry %d, SR2/3 %x/%x, code %d",
886 			device_xname(&sc->sc_dev), i == SR4_DEVICE ? "device" :
887 			(i == SR4_PROTOCOL ? "protocol" :
888 			(i == SR4_SELFTEST ? "selftest" : "unknown")),
889 			sc->sc_stat4 & SR4_RETRYMASK, sc->sc_stat2,
890 			sc->sc_stat3, sc->sc_stat5);
891 
892 		if ((bp->b_flags & B_CMD) && bp->b_cmd == MTRESET)
893 			callout_stop(&sc->sc_intr_ch);
894 		if (sc->sc_stat3 & SR3_POWERUP)
895 			sc->sc_flags &= MTF_OPEN | MTF_EXISTS;
896 		goto error;
897 	}
898 	/*
899 	 * Report and clear any soft errors.
900 	 */
901 	if (sc->sc_stat1 & SR1_SOFTERR) {
902 		printf("%s: soft error, retry %d\n", device_xname(&sc->sc_dev),
903 		    sc->sc_stat4 & SR4_RETRYMASK);
904 		sc->sc_stat1 &= ~SR1_SOFTERR;
905 	}
906 	/*
907 	 * We've initiated a read or write, but haven't actually started to
908 	 * DMA the data yet.  At this point, the drive's ready.
909 	 */
910 	if (sc->sc_flags & MTF_IO) {
911 		sc->sc_flags &= ~MTF_IO;
912 		dir = (bp->b_flags & B_READ ? GPIB_READ : GPIB_WRITE);
913 		gpibxfer(sc->sc_ic, slave,
914 		    dir == GPIB_READ ? MTT_READ : MTL_WRITE,
915 		    bp->b_data, bp->b_bcount, dir, dir == GPIB_READ);
916 		return;
917 	}
918 	/*
919 	 * Check for End Of Tape - we're allowed to hit EOT and then write (or
920 	 * read) one more record.  If we get here and have not already hit EOT,
921 	 * return ENOSPC to inform the process that it's hit it.  If we get
922 	 * here and HAVE already hit EOT, don't allow any more operations that
923 	 * move the tape forward.
924 	 */
925 	if (sc->sc_stat1 & SR1_EOT) {
926 		if (sc->sc_flags & MTF_ATEOT)
927 			sc->sc_flags |= MTF_PASTEOT;
928 		else {
929 			bp->b_error = ENOSPC;
930 			sc->sc_flags |= MTF_ATEOT;
931 		}
932 	}
933 	/*
934 	 * If a motion command was being executed, check for Tape Marks.
935 	 * If we were doing data, make sure we got the right amount, and
936 	 * check for hitting tape marks on reads.
937 	 */
938 	if (bp->b_flags & B_CMD) {
939 		if (sc->sc_stat1 & SR1_EOF) {
940 			if (bp->b_cmd == MTFSR)
941 				sc->sc_flags |= MTF_HITEOF;
942 			if (bp->b_cmd == MTBSR)
943 				sc->sc_flags |= MTF_HITBOF;
944 		}
945 		if (bp->b_cmd == MTRESET) {
946 			callout_stop(&sc->sc_intr_ch);
947 			sc->sc_flags |= MTF_ALIVE;
948 		}
949 	} else {
950 		i = gpibrecv(sc->sc_ic, slave, MTT_BCNT, cmdbuf, 2);
951 		if (i != 2) {
952 			aprint_error_dev(&sc->sc_dev, "intr: can't get xfer length\n");
953 			goto error;
954 		}
955 		i = (int) *((u_short *) cmdbuf);
956 		if (i <= bp->b_bcount) {
957 			if (i == 0)
958 				sc->sc_flags |= MTF_HITEOF;
959 			bp->b_resid = bp->b_bcount - i;
960 			DPRINTF(MDB_ANY, ("%s intr: bcount %ld, resid %ld",
961 			    device_xname(&sc->sc_dev), bp->b_bcount, bp->b_resid));
962 		} else {
963 			tprintf(sc->sc_ttyp,
964 				"%s: record (%d) larger than wanted (%d)\n",
965 				device_xname(&sc->sc_dev), i, bp->b_bcount);
966 error:
967 			sc->sc_flags &= ~MTF_IO;
968 			bp->b_error = EIO;
969 		}
970 	}
971 	/*
972 	 * The operation is completely done.
973 	 * Let the drive know with an END command.
974 	 */
975 	cmdbuf[0] = MTE_COMPLETE | MTE_IDLE;
976 	(void) gpibsend(sc->sc_ic, slave, MTL_ECMD, cmdbuf, 1);
977 	bp->b_flags &= ~B_CMD;
978 	(void)bufq_get(sc->sc_tab);
979 	biodone(bp);
980 	gpibrelease(sc->sc_ic, sc->sc_hdl);
981 	if (bufq_peek(sc->sc_tab) == NULL)
982 		sc->sc_active = 0;
983 	else
984 		mtustart(sc);
985 }
986 
987 int
988 mtread(dev_t dev, struct uio *uio, int flags)
989 {
990 	struct mt_softc *sc;
991 
992 	sc = device_lookup_private(&mt_cd, MTUNIT(dev));
993 
994 	return (physio(mtstrategy, &sc->sc_bufstore,
995 	    dev, B_READ, minphys, uio));
996 }
997 
998 int
999 mtwrite(dev_t dev, struct uio *uio, int flags)
1000 {
1001 	struct mt_softc *sc;
1002 
1003 	sc = device_lookup_private(&mt_cd, MTUNIT(dev));
1004 
1005 	return (physio(mtstrategy, &sc->sc_bufstore,
1006 	    dev, B_WRITE, minphys, uio));
1007 }
1008 
1009 int
1010 mtioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
1011 {
1012 	struct mtop *op;
1013 	int cnt;
1014 
1015 	switch (cmd) {
1016 	    case MTIOCTOP:
1017 		op = (struct mtop *)data;
1018 		switch(op->mt_op) {
1019 		    case MTWEOF:
1020 		    case MTFSF:
1021 		    case MTBSR:
1022 		    case MTBSF:
1023 		    case MTFSR:
1024 			cnt = op->mt_count;
1025 			break;
1026 
1027 		    case MTOFFL:
1028 		    case MTREW:
1029 		    case MTNOP:
1030 			cnt = 0;
1031 			break;
1032 
1033 		    default:
1034 			return (EINVAL);
1035 		}
1036 		return (mtcommand(dev, op->mt_op, cnt));
1037 
1038 	    case MTIOCGET:
1039 		break;
1040 
1041 	    default:
1042 		return (EINVAL);
1043 	}
1044 	return (0);
1045 }
1046