Home | History | Annotate | Line # | Download | only in dev
midi.c revision 1.29 
      1 /*	$NetBSD: midi.c,v 1.29 2002/10/02 16:33:30 thorpej Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1998 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Lennart Augustsson (augustss (at) netbsd.org).
      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  * 3. All advertising materials mentioning features or use of this software
     19  *    must display the following acknowledgement:
     20  *        This product includes software developed by the NetBSD
     21  *        Foundation, Inc. and its contributors.
     22  * 4. Neither the name of The NetBSD Foundation nor the names of its
     23  *    contributors may be used to endorse or promote products derived
     24  *    from this software without specific prior written permission.
     25  *
     26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     36  * POSSIBILITY OF SUCH DAMAGE.
     37  */
     38 
     39 #include <sys/cdefs.h>
     40 __KERNEL_RCSID(0, "$NetBSD: midi.c,v 1.29 2002/10/02 16:33:30 thorpej Exp $");
     41 
     42 #include "midi.h"
     43 #include "sequencer.h"
     44 
     45 #include <sys/param.h>
     46 #include <sys/ioctl.h>
     47 #include <sys/fcntl.h>
     48 #include <sys/vnode.h>
     49 #include <sys/select.h>
     50 #include <sys/poll.h>
     51 #include <sys/malloc.h>
     52 #include <sys/proc.h>
     53 #include <sys/systm.h>
     54 #include <sys/callout.h>
     55 #include <sys/syslog.h>
     56 #include <sys/kernel.h>
     57 #include <sys/signalvar.h>
     58 #include <sys/conf.h>
     59 #include <sys/audioio.h>
     60 #include <sys/midiio.h>
     61 #include <sys/device.h>
     62 
     63 #include <dev/audio_if.h>
     64 #include <dev/midi_if.h>
     65 #include <dev/midivar.h>
     66 
     67 #if NMIDI > 0
     68 
     69 #ifdef AUDIO_DEBUG
     70 #define DPRINTF(x)	if (mididebug) printf x
     71 #define DPRINTFN(n,x)	if (mididebug >= (n)) printf x
     72 int	mididebug = 0;
     73 #else
     74 #define DPRINTF(x)
     75 #define DPRINTFN(n,x)
     76 #endif
     77 
     78 int midi_wait;
     79 
     80 void	midi_in(void *, int);
     81 void	midi_out(void *);
     82 int	midi_start_output(struct midi_softc *, int);
     83 int	midi_sleep_timo(int *, char *, int);
     84 int	midi_sleep(int *, char *);
     85 void	midi_wakeup(int *);
     86 void	midi_initbuf(struct midi_buffer *);
     87 void	midi_timeout(void *);
     88 
     89 int	midiprobe(struct device *, struct cfdata *, void *);
     90 void	midiattach(struct device *, struct device *, void *);
     91 int	mididetach(struct device *, int);
     92 int	midiactivate(struct device *, enum devact);
     93 
     94 dev_type_open(midiopen);
     95 dev_type_close(midiclose);
     96 dev_type_read(midiread);
     97 dev_type_write(midiwrite);
     98 dev_type_ioctl(midiioctl);
     99 dev_type_poll(midipoll);
    100 
    101 const struct cdevsw midi_cdevsw = {
    102 	midiopen, midiclose, midiread, midiwrite, midiioctl,
    103 	nostop, notty, midipoll, nommap,
    104 };
    105 
    106 CFATTACH_DECL(midi, sizeof(struct midi_softc),
    107     midiprobe, midiattach, mididetach, midiactivate);
    108 
    109 #ifdef MIDI_SAVE
    110 #define MIDI_SAVE_SIZE 100000
    111 int midicnt;
    112 struct {
    113 	int cnt;
    114 	u_char buf[MIDI_SAVE_SIZE];
    115 } midisave;
    116 #define MIDI_GETSAVE		_IOWR('m', 100, int)
    117 
    118 #endif
    119 
    120 extern struct cfdriver midi_cd;
    121 
    122 int
    123 midiprobe(struct device *parent, struct cfdata *match, void *aux)
    124 {
    125 	struct audio_attach_args *sa = aux;
    126 
    127 	DPRINTFN(6,("midiprobe: type=%d sa=%p hw=%p\n",
    128 		 sa->type, sa, sa->hwif));
    129 	return (sa->type == AUDIODEV_TYPE_MIDI);
    130 }
    131 
    132 void
    133 midiattach(struct device *parent, struct device *self, void *aux)
    134 {
    135 	struct midi_softc *sc = (void *)self;
    136 	struct audio_attach_args *sa = aux;
    137 	struct midi_hw_if *hwp = sa->hwif;
    138 	void *hdlp = sa->hdl;
    139 
    140 	DPRINTFN(6, ("MIDI attach\n"));
    141 
    142 #ifdef DIAGNOSTIC
    143 	if (hwp == 0 ||
    144 	    hwp->open == 0 ||
    145 	    hwp->close == 0 ||
    146 	    hwp->output == 0 ||
    147 	    hwp->getinfo == 0) {
    148 		printf("midi: missing method\n");
    149 		return;
    150 	}
    151 #endif
    152 
    153 	callout_init(&sc->sc_callout);
    154 
    155 	sc->hw_if = hwp;
    156 	sc->hw_hdl = hdlp;
    157 	sc->dying = 0;
    158 	midi_attach(sc, parent);
    159 }
    160 
    161 int
    162 midiactivate(struct device *self, enum devact act)
    163 {
    164 	struct midi_softc *sc = (struct midi_softc *)self;
    165 
    166 	switch (act) {
    167 	case DVACT_ACTIVATE:
    168 		return (EOPNOTSUPP);
    169 
    170 	case DVACT_DEACTIVATE:
    171 		sc->dying = 1;
    172 		break;
    173 	}
    174 	return (0);
    175 }
    176 
    177 int
    178 mididetach(struct device *self, int flags)
    179 {
    180 	struct midi_softc *sc = (struct midi_softc *)self;
    181 	int maj, mn;
    182 
    183 	DPRINTF(("midi_detach: sc=%p flags=%d\n", sc, flags));
    184 
    185 	sc->dying = 1;
    186 
    187 	wakeup(&sc->wchan);
    188 	wakeup(&sc->rchan);
    189 
    190 	/* locate the major number */
    191 	maj = cdevsw_lookup_major(&midi_cdevsw);
    192 
    193 	/* Nuke the vnodes for any open instances (calls close). */
    194 	mn = self->dv_unit;
    195 	vdevgone(maj, mn, mn, VCHR);
    196 
    197 	return (0);
    198 }
    199 
    200 void
    201 midi_attach(struct midi_softc *sc, struct device *parent)
    202 {
    203 	struct midi_info mi;
    204 
    205 	sc->isopen = 0;
    206 
    207 	midi_wait = MIDI_WAIT * hz / 1000000;
    208 	if (midi_wait == 0)
    209 		midi_wait = 1;
    210 
    211 	sc->sc_dev = parent;
    212 	sc->hw_if->getinfo(sc->hw_hdl, &mi);
    213 	sc->props = mi.props;
    214 	printf(": %s\n", mi.name);
    215 }
    216 
    217 int
    218 midi_unit_count(void)
    219 {
    220 	return midi_cd.cd_ndevs;
    221 }
    222 
    223 void
    224 midi_initbuf(struct midi_buffer *mb)
    225 {
    226 	mb->used = 0;
    227 	mb->usedhigh = MIDI_BUFSIZE;
    228 	mb->end = mb->start + mb->usedhigh;
    229 	mb->inp = mb->outp = mb->start;
    230 }
    231 
    232 int
    233 midi_sleep_timo(int *chan, char *label, int timo)
    234 {
    235 	int st;
    236 
    237 	if (!label)
    238 		label = "midi";
    239 
    240 	DPRINTFN(5, ("midi_sleep_timo: %p %s %d\n", chan, label, timo));
    241 	*chan = 1;
    242 	st = tsleep(chan, PWAIT | PCATCH, label, timo);
    243 	*chan = 0;
    244 #ifdef MIDI_DEBUG
    245 	if (st != 0)
    246 		printf("midi_sleep: %d\n", st);
    247 #endif
    248 	return st;
    249 }
    250 
    251 int
    252 midi_sleep(int *chan, char *label)
    253 {
    254 	return midi_sleep_timo(chan, label, 0);
    255 }
    256 
    257 void
    258 midi_wakeup(int *chan)
    259 {
    260 	if (*chan) {
    261 		DPRINTFN(5, ("midi_wakeup: %p\n", chan));
    262 		wakeup(chan);
    263 		*chan = 0;
    264 	}
    265 }
    266 
    267 static int midi_lengths[] = { 2,2,2,2,1,1,2,0 };
    268 /* Number of bytes in a MIDI command */
    269 #define MIDI_LENGTH(d) (midi_lengths[((d) >> 4) & 7])
    270 
    271 void
    272 midi_in(void *addr, int data)
    273 {
    274 	struct midi_softc *sc = addr;
    275 	struct midi_buffer *mb = &sc->inbuf;
    276 	int i;
    277 
    278 	if (!sc->isopen)
    279 		return;
    280 	if (data == MIDI_ACK)
    281 		return;
    282 
    283 	DPRINTFN(3, ("midi_in: sc=%p data=0x%02x state=%d pos=%d\n",
    284 		     sc, data, sc->in_state, sc->in_pos));
    285 
    286 	if (!(sc->flags & FREAD))
    287 		return;		/* discard data if not reading */
    288 
    289 	switch(sc->in_state) {
    290 	case MIDI_IN_START:
    291 		if (MIDI_IS_STATUS(data)) {
    292 			switch(data) {
    293 			case 0xf0: /* Sysex */
    294 				sc->in_state = MIDI_IN_SYSEX;
    295 				break;
    296 			case 0xf1: /* MTC quarter frame */
    297 			case 0xf3: /* Song select */
    298 				sc->in_state = MIDI_IN_DATA;
    299 				sc->in_msg[0] = data;
    300 				sc->in_pos = 1;
    301 				sc->in_left = 1;
    302 				break;
    303 			case 0xf2: /* Song position pointer */
    304 				sc->in_state = MIDI_IN_DATA;
    305 				sc->in_msg[0] = data;
    306 				sc->in_pos = 1;
    307 				sc->in_left = 2;
    308 				break;
    309 			default:
    310 				if (MIDI_IS_COMMON(data)) {
    311 					sc->in_msg[0] = data;
    312 					sc->in_pos = 1;
    313 					goto deliver;
    314 				} else {
    315 					sc->in_state = MIDI_IN_DATA;
    316 					sc->in_msg[0] = sc->in_status = data;
    317 					sc->in_pos = 1;
    318 					sc->in_left = MIDI_LENGTH(data);
    319 				}
    320 				break;
    321 			}
    322 		} else {
    323 			if (MIDI_IS_STATUS(sc->in_status)) {
    324 				sc->in_state = MIDI_IN_DATA;
    325 				sc->in_msg[0] = sc->in_status;
    326 				sc->in_msg[1] = data;
    327 				sc->in_pos = 2;
    328 				sc->in_left = MIDI_LENGTH(sc->in_status) - 1;
    329 			}
    330 		}
    331 		return;
    332 	case MIDI_IN_DATA:
    333 		sc->in_msg[sc->in_pos++] = data;
    334 		if (--sc->in_left <= 0)
    335 			break;	/* deliver data */
    336 		return;
    337 	case MIDI_IN_SYSEX:
    338 		if (data == MIDI_SYSEX_END)
    339 			sc->in_state = MIDI_IN_START;
    340 		return;
    341 	}
    342 deliver:
    343 	sc->in_state = MIDI_IN_START;
    344 #if NSEQUENCER > 0
    345 	if (sc->seqopen) {
    346 		extern void midiseq_in(struct midi_dev *,u_char *,int);
    347 		midiseq_in(sc->seq_md, sc->in_msg, sc->in_pos);
    348 		return;
    349 	}
    350 #endif
    351 
    352 	if (mb->used + sc->in_pos > mb->usedhigh) {
    353 		DPRINTF(("midi_in: buffer full, discard data=0x%02x\n",
    354 			 sc->in_msg[0]));
    355 		return;
    356 	}
    357 	for (i = 0; i < sc->in_pos; i++) {
    358 		*mb->inp++ = sc->in_msg[i];
    359 		if (mb->inp >= mb->end)
    360 			mb->inp = mb->start;
    361 		mb->used++;
    362 	}
    363 	midi_wakeup(&sc->rchan);
    364 	selwakeup(&sc->rsel);
    365 	if (sc->async)
    366 		psignal(sc->async, SIGIO);
    367 }
    368 
    369 void
    370 midi_out(void *addr)
    371 {
    372 	struct midi_softc *sc = addr;
    373 
    374 	if (!sc->isopen)
    375 		return;
    376 	DPRINTFN(3, ("midi_out: %p\n", sc));
    377 	midi_start_output(sc, 1);
    378 }
    379 
    380 int
    381 midiopen(dev_t dev, int flags, int ifmt, struct proc *p)
    382 {
    383 	struct midi_softc *sc;
    384 	struct midi_hw_if *hw;
    385 	int error;
    386 
    387 	sc = device_lookup(&midi_cd, MIDIUNIT(dev));
    388 	if (sc == NULL)
    389 		return (ENXIO);
    390 	if (sc->dying)
    391 		return (EIO);
    392 
    393 	DPRINTF(("midiopen %p\n", sc));
    394 
    395 	hw = sc->hw_if;
    396 	if (!hw)
    397 		return ENXIO;
    398 	if (sc->isopen)
    399 		return EBUSY;
    400 	sc->in_state = MIDI_IN_START;
    401 	sc->in_status = 0;
    402 	error = hw->open(sc->hw_hdl, flags, midi_in, midi_out, sc);
    403 	if (error)
    404 		return error;
    405 	sc->isopen++;
    406 	midi_initbuf(&sc->outbuf);
    407 	midi_initbuf(&sc->inbuf);
    408 	sc->flags = flags;
    409 	sc->rchan = 0;
    410 	sc->wchan = 0;
    411 	sc->pbus = 0;
    412 	sc->async = 0;
    413 
    414 #ifdef MIDI_SAVE
    415 	if (midicnt != 0) {
    416 		midisave.cnt = midicnt;
    417 		midicnt = 0;
    418 	}
    419 #endif
    420 
    421 	return 0;
    422 }
    423 
    424 int
    425 midiclose(dev_t dev, int flags, int ifmt, struct proc *p)
    426 {
    427 	int unit = MIDIUNIT(dev);
    428 	struct midi_softc *sc = midi_cd.cd_devs[unit];
    429 	struct midi_hw_if *hw = sc->hw_if;
    430 	int s, error;
    431 
    432 	DPRINTF(("midiclose %p\n", sc));
    433 
    434 	midi_start_output(sc, 0);
    435 	error = 0;
    436 	s = splaudio();
    437 	while (sc->outbuf.used > 0 && !error) {
    438 		DPRINTFN(2,("midiclose sleep used=%d\n", sc->outbuf.used));
    439 		error = midi_sleep_timo(&sc->wchan, "mid_dr", 30*hz);
    440 	}
    441 	splx(s);
    442 	sc->isopen = 0;
    443 	hw->close(sc->hw_hdl);
    444 #if NSEQUENCER > 0
    445 	sc->seqopen = 0;
    446 	sc->seq_md = 0;
    447 #endif
    448 	return 0;
    449 }
    450 
    451 int
    452 midiread(dev_t dev, struct uio *uio, int ioflag)
    453 {
    454 	int unit = MIDIUNIT(dev);
    455 	struct midi_softc *sc = midi_cd.cd_devs[unit];
    456 	struct midi_buffer *mb = &sc->inbuf;
    457 	int error;
    458 	u_char *outp;
    459 	int used, cc, n, resid;
    460 	int s;
    461 
    462 	DPRINTF(("midiread: %p, count=%lu\n", sc,
    463 		 (unsigned long)uio->uio_resid));
    464 
    465 	if (sc->dying)
    466 		return EIO;
    467 
    468 	error = 0;
    469 	resid = uio->uio_resid;
    470 	while (uio->uio_resid == resid && !error) {
    471 		s = splaudio();
    472 		while (mb->used <= 0) {
    473 			if (ioflag & IO_NDELAY) {
    474 				splx(s);
    475 				return EWOULDBLOCK;
    476 			}
    477 			error = midi_sleep(&sc->rchan, "mid rd");
    478 			if (error) {
    479 				splx(s);
    480 				return error;
    481 			}
    482 		}
    483 		used = mb->used;
    484 		outp = mb->outp;
    485 		splx(s);
    486 		if (sc->dying)
    487 			return EIO;
    488 		cc = used;	/* maximum to read */
    489 		n = mb->end - outp;
    490 		if (n < cc)
    491 			cc = n;	/* don't read beyond end of buffer */
    492 		if (uio->uio_resid < cc)
    493 			cc = uio->uio_resid; /* and no more than we want */
    494 		DPRINTFN(3, ("midiread: uiomove cc=%d\n", cc));
    495 		error = uiomove(outp, cc, uio);
    496 		if (error)
    497 			break;
    498 		used -= cc;
    499 		outp += cc;
    500 		if (outp >= mb->end)
    501 			outp = mb->start;
    502 		s = splaudio();
    503 		mb->outp = outp;
    504 		mb->used = used;
    505 		splx(s);
    506 	}
    507 	return error;
    508 }
    509 
    510 void
    511 midi_timeout(void *arg)
    512 {
    513 	struct midi_softc *sc = arg;
    514 
    515 	DPRINTFN(3,("midi_timeout: %p\n", sc));
    516 	midi_start_output(sc, 1);
    517 }
    518 
    519 int
    520 midi_start_output(struct midi_softc *sc, int intr)
    521 {
    522 	struct midi_buffer *mb = &sc->outbuf;
    523 	u_char out;
    524 	int error;
    525 	int s;
    526 	int i;
    527 
    528 	error = 0;
    529 
    530 	if (sc->dying)
    531 		return EIO;
    532 
    533 	if (sc->pbus && !intr) {
    534 		DPRINTFN(4, ("midi_start_output: busy\n"));
    535 		return 0;
    536 	}
    537 	sc->pbus = (mb->used > 0)?1:0;
    538 	for (i = 0; i < MIDI_MAX_WRITE && mb->used > 0 &&
    539 		   (!error || error==EINPROGRESS); i++) {
    540 		s = splaudio();
    541 		out = *mb->outp;
    542 		mb->outp++;
    543 		if (mb->outp >= mb->end)
    544 			mb->outp = mb->start;
    545 		mb->used--;
    546 		splx(s);
    547 #ifdef MIDI_SAVE
    548 		midisave.buf[midicnt] = out;
    549 		midicnt = (midicnt + 1) % MIDI_SAVE_SIZE;
    550 #endif
    551 		DPRINTFN(4, ("midi_start_output: %p i=%d, data=0x%02x\n",
    552 			     sc, i, out));
    553 		error = sc->hw_if->output(sc->hw_hdl, out);
    554 		if ((sc->props & MIDI_PROP_OUT_INTR) && error!=EINPROGRESS)
    555 			/* If ointr is enabled, midi_start_output()
    556 			 * normally writes only one byte,
    557 			 * except hw_if->output() returns EINPROGRESS.
    558 			 */
    559 			break;
    560 	}
    561 	midi_wakeup(&sc->wchan);
    562 	selwakeup(&sc->wsel);
    563 	if (sc->async)
    564 		psignal(sc->async, SIGIO);
    565 	if (!(sc->props & MIDI_PROP_OUT_INTR) || error==EINPROGRESS) {
    566 		if (mb->used > 0)
    567 			callout_reset(&sc->sc_callout, midi_wait,
    568 				      midi_timeout, sc);
    569 		else
    570 			sc->pbus = 0;
    571 	}
    572 	if ((sc->props & MIDI_PROP_OUT_INTR) && error==EINPROGRESS)
    573 		error = 0;
    574 
    575 	return error;
    576 }
    577 
    578 int
    579 midiwrite(dev_t dev, struct uio *uio, int ioflag)
    580 {
    581 	int unit = MIDIUNIT(dev);
    582 	struct midi_softc *sc = midi_cd.cd_devs[unit];
    583 	struct midi_buffer *mb = &sc->outbuf;
    584 	int error;
    585 	u_char *inp;
    586 	int used, cc, n;
    587 	int s;
    588 
    589 	DPRINTFN(2, ("midiwrite: %p, unit=%d, count=%lu\n", sc, unit,
    590 		     (unsigned long)uio->uio_resid));
    591 
    592 	if (sc->dying)
    593 		return EIO;
    594 
    595 	error = 0;
    596 	while (uio->uio_resid > 0 && !error) {
    597 		s = splaudio();
    598 		if (mb->used >= mb->usedhigh) {
    599 			DPRINTFN(3,("midi_write: sleep used=%d hiwat=%d\n",
    600 				 mb->used, mb->usedhigh));
    601 			if (ioflag & IO_NDELAY) {
    602 				splx(s);
    603 				return EWOULDBLOCK;
    604 			}
    605 			error = midi_sleep(&sc->wchan, "mid wr");
    606 			if (error) {
    607 				splx(s);
    608 				return error;
    609 			}
    610 		}
    611 		used = mb->used;
    612 		inp = mb->inp;
    613 		splx(s);
    614 		if (sc->dying)
    615 			return EIO;
    616 		cc = mb->usedhigh - used; 	/* maximum to write */
    617 		n = mb->end - inp;
    618 		if (n < cc)
    619 			cc = n;		/* don't write beyond end of buffer */
    620 		if (uio->uio_resid < cc)
    621 			cc = uio->uio_resid; 	/* and no more than we have */
    622 		error = uiomove(inp, cc, uio);
    623 #ifdef MIDI_DEBUG
    624 		if (error)
    625 		        printf("midi_write:(1) uiomove failed %d; "
    626 			       "cc=%d inp=%p\n",
    627 			       error, cc, inp);
    628 #endif
    629 		if (error)
    630 			break;
    631 		inp = mb->inp + cc;
    632 		if (inp >= mb->end)
    633 			inp = mb->start;
    634 		s = splaudio();
    635 		mb->inp = inp;
    636 		mb->used += cc;
    637 		splx(s);
    638 		error = midi_start_output(sc, 0);
    639 	}
    640 	return error;
    641 }
    642 
    643 /*
    644  * This write routine is only called from sequencer code and expects
    645  * a write that is smaller than the MIDI buffer.
    646  */
    647 int
    648 midi_writebytes(int unit, u_char *buf, int cc)
    649 {
    650 	struct midi_softc *sc = midi_cd.cd_devs[unit];
    651 	struct midi_buffer *mb = &sc->outbuf;
    652 	int n, s;
    653 
    654 	DPRINTFN(2, ("midi_writebytes: %p, unit=%d, cc=%d\n", sc, unit, cc));
    655 	DPRINTFN(3, ("midi_writebytes: %x %x %x\n",buf[0],buf[1],buf[2]));
    656 
    657 	if (sc->dying)
    658 		return EIO;
    659 
    660 	s = splaudio();
    661 	if (mb->used + cc >= mb->usedhigh) {
    662 		splx(s);
    663 		return (EWOULDBLOCK);
    664 	}
    665 	n = mb->end - mb->inp;
    666 	if (cc < n)
    667 		n = cc;
    668 	mb->used += cc;
    669 	memcpy(mb->inp, buf, n);
    670 	mb->inp += n;
    671 	if (mb->inp >= mb->end) {
    672 		mb->inp = mb->start;
    673 		cc -= n;
    674 		if (cc > 0) {
    675 			memcpy(mb->inp, buf + n, cc);
    676 			mb->inp += cc;
    677 		}
    678 	}
    679 	splx(s);
    680 	return (midi_start_output(sc, 0));
    681 }
    682 
    683 int
    684 midiioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p)
    685 {
    686 	int unit = MIDIUNIT(dev);
    687 	struct midi_softc *sc = midi_cd.cd_devs[unit];
    688 	struct midi_hw_if *hw = sc->hw_if;
    689 	int error;
    690 
    691 	DPRINTF(("midiioctl: %p cmd=0x%08lx\n", sc, cmd));
    692 
    693 	if (sc->dying)
    694 		return EIO;
    695 
    696 	error = 0;
    697 	switch (cmd) {
    698 	case FIONBIO:
    699 		/* All handled in the upper FS layer. */
    700 		break;
    701 
    702 	case FIOASYNC:
    703 		if (*(int *)addr) {
    704 			if (sc->async)
    705 				return EBUSY;
    706 			sc->async = p;
    707 			DPRINTF(("midi_ioctl: FIOASYNC %p\n", p));
    708 		} else
    709 			sc->async = 0;
    710 		break;
    711 
    712 #if 0
    713 	case MIDI_PRETIME:
    714 		/* XXX OSS
    715 		 * This should set up a read timeout, but that's
    716 		 * why we have poll(), so there's nothing yet. */
    717 		error = EINVAL;
    718 		break;
    719 #endif
    720 
    721 #ifdef MIDI_SAVE
    722 	case MIDI_GETSAVE:
    723 		error = copyout(&midisave, *(void **)addr, sizeof midisave);
    724   		break;
    725 #endif
    726 
    727 	default:
    728 		if (hw->ioctl)
    729 			error = hw->ioctl(sc->hw_hdl, cmd, addr, flag, p);
    730 		else
    731 			error = EINVAL;
    732 		break;
    733 	}
    734 	return error;
    735 }
    736 
    737 int
    738 midipoll(dev_t dev, int events, struct proc *p)
    739 {
    740 	int unit = MIDIUNIT(dev);
    741 	struct midi_softc *sc = midi_cd.cd_devs[unit];
    742 	int revents = 0;
    743 	int s;
    744 
    745 	DPRINTF(("midipoll: %p events=0x%x\n", sc, events));
    746 
    747 	if (sc->dying)
    748 		return EIO;
    749 
    750 	s = splaudio();
    751 
    752 	if (events & (POLLIN | POLLRDNORM))
    753 		if (sc->inbuf.used > 0)
    754 			revents |= events & (POLLIN | POLLRDNORM);
    755 
    756 	if (events & (POLLOUT | POLLWRNORM))
    757 		if (sc->outbuf.used < sc->outbuf.usedhigh)
    758 			revents |= events & (POLLOUT | POLLWRNORM);
    759 
    760 	if (revents == 0) {
    761 		if (events & (POLLIN | POLLRDNORM))
    762 			selrecord(p, &sc->rsel);
    763 
    764 		if (events & (POLLOUT | POLLWRNORM))
    765 			selrecord(p, &sc->wsel);
    766 	}
    767 
    768 	splx(s);
    769 	return revents;
    770 }
    771 
    772 void
    773 midi_getinfo(dev_t dev, struct midi_info *mi)
    774 {
    775 	struct midi_softc *sc;
    776 
    777 	sc = device_lookup(&midi_cd, MIDIUNIT(dev));
    778 	if (sc == NULL)
    779 		return;
    780 	if (sc->dying)
    781 		return;
    782 
    783 	sc->hw_if->getinfo(sc->hw_hdl, mi);
    784 }
    785 
    786 #endif /* NMIDI > 0 */
    787 
    788 #if NMIDI > 0 || NMIDIBUS > 0
    789 
    790 int	audioprint(void *, const char *);
    791 
    792 struct device *
    793 midi_attach_mi(struct midi_hw_if *mhwp, void *hdlp, struct device *dev)
    794 {
    795 	struct audio_attach_args arg;
    796 
    797 #ifdef DIAGNOSTIC
    798 	if (mhwp == NULL) {
    799 		printf("midi_attach_mi: NULL\n");
    800 		return (0);
    801 	}
    802 #endif
    803 	arg.type = AUDIODEV_TYPE_MIDI;
    804 	arg.hwif = mhwp;
    805 	arg.hdl = hdlp;
    806 	return (config_found(dev, &arg, audioprint));
    807 }
    808 
    809 #endif /* NMIDI > 0 || NMIDIBUS > 0 */
    810