midisyn.c revision 1.3 
1/*	$NetBSD: midisyn.c,v 1.3 1998/08/17 21:16:12 augustss Exp $	*/
2
3/*
4 * Copyright (c) 1998 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * Author: Lennart Augustsson
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 *    must display the following acknowledgement:
19 *        This product includes software developed by the NetBSD
20 *        Foundation, Inc. and its contributors.
21 * 4. Neither the name of The NetBSD Foundation nor the names of its
22 *    contributors may be used to endorse or promote products derived
23 *    from this software without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
26 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35 * POSSIBILITY OF SUCH DAMAGE.
36 */
37
38#include <sys/param.h>
39#include <sys/ioctl.h>
40#include <sys/fcntl.h>
41#include <sys/vnode.h>
42#include <sys/select.h>
43#include <sys/proc.h>
44#include <sys/malloc.h>
45#include <sys/systm.h>
46#include <sys/syslog.h>
47#include <sys/kernel.h>
48#include <sys/conf.h>
49#include <sys/audioio.h>
50#include <sys/midiio.h>
51#include <sys/device.h>
52
53#include <dev/audio_if.h>
54#include <dev/midi_if.h>
55#include <dev/midivar.h>
56#include <dev/midisynvar.h>
57
58#ifdef AUDIO_DEBUG
59#define DPRINTF(x)	if (midisyndebug) printf x
60#define DPRINTFN(n,x)	if (midisyndebug >= (n)) printf x
61int	midisyndebug = 0;
62#else
63#define DPRINTF(x)
64#define DPRINTFN(n,x)
65#endif
66
67int	midisyn_findvoice __P((midisyn *, int, int));
68void	midisyn_freevoice __P((midisyn *, int));
69int	midisyn_allocvoice __P((midisyn *, u_int32_t, u_int32_t));
70u_int32_t midisyn_note_to_freq __P((int));
71u_int32_t midisyn_finetune __P((u_int32_t, int, int, int));
72
73int	midisyn_open __P((void *, int,
74			  void (*iintr)__P((void *, int)),
75			  void (*ointr)__P((void *)), void *arg));
76void	midisyn_close __P((void *));
77int	midisyn_output __P((void *, int));
78void	midisyn_getinfo __P((void *, struct midi_info *));
79int	midisyn_ioctl __P((void *, u_long, caddr_t, int, struct proc *));
80
81struct midi_hw_if midisyn_hw_if = {
82	midisyn_open,
83	midisyn_close,
84	midisyn_output,
85	midisyn_getinfo,
86	midisyn_ioctl,
87};
88
89static int midi_lengths[] = { 3,3,3,3,2,2,3,1 };
90/* Number of bytes in a MIDI command, including status */
91#define MIDI_LENGTH(d) (midi_lengths[((d) >> 4) & 7])
92
93int
94midisyn_open(addr, flags, iintr, ointr, arg)
95	void *addr;
96	int flags;
97	void (*iintr)__P((void *, int));
98	void (*ointr)__P((void *));
99	void *arg;
100{
101	midisyn *ms = addr;
102
103	DPRINTF(("midisyn_open: ms=%p ms->mets=%p\n", ms, ms->mets));
104	if (ms->mets->open)
105		return (ms->mets->open(ms, flags));
106	else
107		return (0);
108}
109
110void
111midisyn_close(addr)
112	void *addr;
113{
114	midisyn *ms = addr;
115
116	DPRINTF(("midisyn_close: ms=%p ms->mets=%p\n", ms, ms->mets));
117	if (ms->mets->close)
118		ms->mets->close(ms);
119}
120
121void
122midisyn_getinfo(addr, mi)
123	void *addr;
124	struct midi_info *mi;
125{
126	midisyn *ms = addr;
127
128	mi->name = ms->name;
129	mi->props = 0;
130}
131
132int
133midisyn_ioctl(maddr, cmd, addr, flag, p)
134	void *maddr;
135	u_long cmd;
136	caddr_t addr;
137	int flag;
138	struct proc *p;
139{
140	midisyn *ms = maddr;
141
142	if (ms->mets->ioctl)
143		return (ms->mets->ioctl(ms, cmd, addr, flag, p));
144	else
145		return (EINVAL);
146}
147
148int
149midisyn_findvoice(ms, chan, note)
150	midisyn *ms;
151	int chan, note;
152{
153	u_int cn;
154	int v;
155
156	if (!(ms->flags & MS_DOALLOC))
157		return (chan);
158	cn = MS_CHANNOTE(chan, note);
159	for (v = 0; v < ms->nvoice; v++)
160		if (ms->voices[v].chan_note == cn && ms->voices[v].inuse)
161			return (v);
162	return (-1);
163}
164
165void
166midisyn_attach(sc, ms)
167	struct midi_softc *sc;
168	midisyn *ms;
169{
170	if (ms->flags & MS_DOALLOC) {
171		ms->voices = malloc(ms->nvoice * sizeof (struct voice),
172				    M_DEVBUF, M_WAITOK);
173		memset(ms->voices, 0, ms->nvoice * sizeof (struct voice));
174		ms->seqno = 1;
175		if (ms->mets->allocv == 0)
176			ms->mets->allocv = &midisyn_allocvoice;
177	}
178	sc->hw_if = &midisyn_hw_if;
179	sc->hw_hdl = ms;
180	DPRINTF(("midisyn_attach: ms=%p\n", sc->hw_hdl));
181}
182
183void
184midisyn_freevoice(ms, voice)
185	midisyn *ms;
186	int voice;
187{
188	if (!(ms->flags & MS_DOALLOC))
189		return;
190	ms->voices[voice].inuse = 0;
191}
192
193int
194midisyn_allocvoice(ms, chan, note)
195	midisyn *ms;
196	u_int32_t chan, note;
197{
198	int bestv, v;
199	u_int bestseq, s;
200
201	if (!(ms->flags & MS_DOALLOC))
202		return (chan);
203	/* Find a free voice, or if no free voice is found the oldest. */
204	bestv = 0;
205	bestseq = ms->voices[0].seqno + (ms->voices[0].inuse ? 0x40000000 : 0);
206	for (v = 1; v < ms->nvoice; v++) {
207		s = ms->voices[v].seqno;
208		if (ms->voices[v].inuse)
209			s += 0x40000000;
210		if (s < bestseq) {
211			bestseq = s;
212			bestv = v;
213		}
214	}
215	DPRINTFN(10,("midisyn_allocvoice: v=%d seq=%d cn=%x inuse=%d\n",
216		     bestv, ms->voices[bestv].seqno,
217		     ms->voices[bestv].chan_note,
218		     ms->voices[bestv].inuse));
219#ifdef AUDIO_DEBUG
220	if (ms->voices[bestv].inuse)
221		DPRINTFN(1,("midisyn_allocvoice: steal %x\n",
222			    ms->voices[bestv].chan_note));
223#endif
224	ms->voices[bestv].chan_note = MS_CHANNOTE(chan, note);
225	ms->voices[bestv].seqno = ms->seqno++;
226	ms->voices[bestv].inuse = 1;
227	return (bestv);
228}
229
230int
231midisyn_output(addr, b)
232	void *addr;
233	int b;
234{
235	midisyn *ms = addr;
236	u_int8_t status, chan;
237	int voice = 0;		/* initialize to keep gcc quiet */
238	struct midisyn_methods *fs;
239	u_int32_t note, vel;
240
241	DPRINTF(("midisyn_output: ms=%p b=0x%02x\n", ms, b));
242	fs = ms->mets;
243	if (ms->pos < 0) {
244		/* Doing SYSEX */
245		DPRINTF(("midisyn_output: sysex 0x%02x\n", b));
246		if (fs->sysex)
247			fs->sysex(ms, b);
248		if (b == MIDI_SYSEX_END)
249			ms->pos = 0;
250		return (0);
251	}
252	if (ms->pos == 0 && !MIDI_IS_STATUS(b))
253		ms->pos++;	/* repeat last status byte */
254	ms->buf[ms->pos++] = b;
255	status = ms->buf[0];
256	if (ms->pos < MIDI_LENGTH(status))
257		return (0);
258	/* Decode the MIDI command */
259	chan = MIDI_GET_CHAN(status);
260	note = ms->buf[1];
261	if (ms->flags & MS_FREQXLATE)
262		note = midisyn_note_to_freq(note);
263	vel = ms->buf[2];
264	switch (MIDI_GET_STATUS(status)) {
265	case MIDI_NOTEOFF:
266		voice = midisyn_findvoice(ms, chan, ms->buf[1]);
267		if (voice >= 0) {
268			fs->noteoff(ms, voice, note, vel);
269			midisyn_freevoice(ms, voice);
270		}
271		break;
272	case MIDI_NOTEON:
273		voice = fs->allocv(ms, chan, ms->buf[1]);
274		fs->noteon(ms, voice, note, vel);
275		break;
276	case MIDI_KEY_PRESSURE:
277		if (fs->keypres) {
278			voice = midisyn_findvoice(ms, voice, ms->buf[1]);
279			if (voice >= 0)
280				fs->keypres(ms, voice, note, vel);
281		}
282		break;
283	case MIDI_CTL_CHANGE:
284		if (fs->ctlchg)
285			fs->ctlchg(ms, chan, ms->buf[1], vel);
286		break;
287	case MIDI_PGM_CHANGE:
288		if (fs->pgmchg)
289			fs->pgmchg(ms, chan, ms->buf[1]);
290		break;
291	case MIDI_CHN_PRESSURE:
292		if (fs->chnpres) {
293			voice = midisyn_findvoice(ms, chan, ms->buf[1]);
294			if (voice >= 0)
295				fs->chnpres(ms, voice, note);
296		}
297		break;
298	case MIDI_PITCH_BEND:
299		if (fs->pitchb) {
300			voice = midisyn_findvoice(ms, chan, ms->buf[1]);
301			if (voice >= 0)
302				fs->pitchb(ms, chan, note, vel);
303		}
304		break;
305	case MIDI_SYSTEM_PREFIX:
306		if (fs->sysex)
307			fs->sysex(ms, status);
308		ms->pos = -1;
309		return (0);
310	}
311	ms->pos = 0;
312	return (0);
313}
314
315/*
316 * Convert a MIDI note to the corresponding frequency.
317 * The frequency is scaled by 2^16.
318 */
319u_int32_t
320midisyn_note_to_freq(note)
321	int note;
322{
323	int o, n, f;
324#define BASE_OCTAVE 5
325	static u_int32_t notes[] = {
326		17145893, 18165441, 19245614, 20390018, 21602472, 22887021,
327		24247954, 25689813, 27217409, 28835840, 30550508, 32367136
328	};
329
330
331	o = note / 12;
332	n = note % 12;
333
334	f = notes[n];
335
336	if (o < BASE_OCTAVE)
337		f >>= (BASE_OCTAVE - o);
338	else if (o > BASE_OCTAVE)
339		f <<= (o - BASE_OCTAVE);
340	return (f);
341}
342
343u_int32_t
344midisyn_finetune(base_freq, bend, range, vibrato_cents)
345	u_int32_t base_freq;
346	int bend;
347	int range;
348	int vibrato_cents;
349{
350	static u_int16_t semitone_tuning[24] =
351	{
352/*   0 */ 10000, 10595, 11225, 11892, 12599, 13348, 14142, 14983,
353/*   8 */ 15874, 16818, 17818, 18877, 20000, 21189, 22449, 23784,
354/*  16 */ 25198, 26697, 28284, 29966, 31748, 33636, 35636, 37755
355	};
356	static u_int16_t cent_tuning[100] =
357	{
358/*   0 */ 10000, 10006, 10012, 10017, 10023, 10029, 10035, 10041,
359/*   8 */ 10046, 10052, 10058, 10064, 10070, 10075, 10081, 10087,
360/*  16 */ 10093, 10099, 10105, 10110, 10116, 10122, 10128, 10134,
361/*  24 */ 10140, 10145, 10151, 10157, 10163, 10169, 10175, 10181,
362/*  32 */ 10187, 10192, 10198, 10204, 10210, 10216, 10222, 10228,
363/*  40 */ 10234, 10240, 10246, 10251, 10257, 10263, 10269, 10275,
364/*  48 */ 10281, 10287, 10293, 10299, 10305, 10311, 10317, 10323,
365/*  56 */ 10329, 10335, 10341, 10347, 10353, 10359, 10365, 10371,
366/*  64 */ 10377, 10383, 10389, 10395, 10401, 10407, 10413, 10419,
367/*  72 */ 10425, 10431, 10437, 10443, 10449, 10455, 10461, 10467,
368/*  80 */ 10473, 10479, 10485, 10491, 10497, 10503, 10509, 10515,
369/*  88 */ 10521, 10528, 10534, 10540, 10546, 10552, 10558, 10564,
370/*  96 */ 10570, 10576, 10582, 10589
371	};
372	u_int32_t amount;
373	int negative, semitones, cents, multiplier;
374
375	if (range == 0)
376		return base_freq;
377
378	if (base_freq == 0)
379		return base_freq;
380
381	if (range >= 8192)
382		range = 8192;
383
384	bend = bend * range / 8192;
385	bend += vibrato_cents;
386
387	if (bend == 0)
388		return base_freq;
389
390	if (bend < 0) {
391		bend = -bend;
392		negative = 1;
393	} else
394		negative = 0;
395
396	if (bend > range)
397		bend = range;
398
399	multiplier = 1;
400	while (bend > 2399) {
401		multiplier *= 4;
402		bend -= 2400;
403	}
404
405	semitones = bend / 100;
406	if (semitones > 99)
407		semitones = 99;
408	cents = bend % 100;
409
410	amount = semitone_tuning[semitones] * multiplier * cent_tuning[cents]
411		/ 10000;
412
413	if (negative)
414		return (base_freq * 10000 / amount);	/* Bend down */
415	else
416		return (base_freq * amount / 10000);	/* Bend up */
417}
418
419