1 /* $NetBSD: midisyn.c,v 1.25 2019/05/08 13:40:17 isaki Exp $ */ 2 3 /* 4 * Copyright (c) 1998, 2008 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), and by Andrew Doran. 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 #include <sys/cdefs.h> 33 __KERNEL_RCSID(0, "$NetBSD: midisyn.c,v 1.25 2019/05/08 13:40:17 isaki Exp $"); 34 35 #include <sys/param.h> 36 #include <sys/ioctl.h> 37 #include <sys/fcntl.h> 38 #include <sys/vnode.h> 39 #include <sys/select.h> 40 #include <sys/proc.h> 41 #include <sys/kmem.h> 42 #include <sys/systm.h> 43 #include <sys/syslog.h> 44 #include <sys/kernel.h> 45 #include <sys/audioio.h> 46 #include <sys/midiio.h> 47 #include <sys/device.h> 48 49 #include <dev/audio/audio_if.h> 50 #include <dev/midi_if.h> 51 #include <dev/midivar.h> 52 #include <dev/midisynvar.h> 53 54 #ifdef AUDIO_DEBUG 55 #define DPRINTF(x) if (midisyndebug) printf x 56 #define DPRINTFN(n,x) if (midisyndebug >= (n)) printf x 57 int midisyndebug = 0; 58 #else 59 #define DPRINTF(x) 60 #define DPRINTFN(n,x) 61 #endif 62 63 static int midisyn_findvoice(midisyn *, int, int); 64 static void midisyn_freevoice(midisyn *, int); 65 static uint_fast16_t midisyn_allocvoice(midisyn *, uint_fast8_t, uint_fast8_t); 66 static void midisyn_attackv_vel(midisyn *, uint_fast16_t, midipitch_t, 67 int16_t, uint_fast8_t); 68 69 static midictl_notify midisyn_notify; 70 71 static midipitch_t midisyn_clamp_pitch(midipitch_t); 72 static int16_t midisyn_adj_level(midisyn *, uint_fast8_t); 73 static midipitch_t midisyn_adj_pitch(midisyn *, uint_fast8_t); 74 static void midisyn_chan_releasev(midisyn *, uint_fast8_t, uint_fast8_t); 75 static void midisyn_upd_level(midisyn *, uint_fast8_t); 76 static void midisyn_upd_pitch(midisyn *, uint_fast8_t); 77 78 static int midisyn_open(void *, int, 79 void (*iintr)(void *, int), 80 void (*ointr)(void *), void *arg); 81 static void midisyn_close(void *); 82 static int midisyn_sysrt(void *, int); 83 static void midisyn_getinfo(void *, struct midi_info *); 84 static int midisyn_ioctl(void *, u_long, void *, int, struct lwp *); 85 static void midisyn_get_locks(void *, kmutex_t **, kmutex_t **); 86 87 const struct midi_hw_if midisyn_hw_if = { 88 midisyn_open, 89 midisyn_close, 90 midisyn_sysrt, 91 midisyn_getinfo, 92 midisyn_ioctl, 93 midisyn_get_locks, 94 }; 95 96 static int midisyn_channelmsg(void *, int, int, u_char *, int); 97 static int midisyn_commonmsg(void *, int, u_char *, int); 98 static int midisyn_sysex(void *, u_char *, int); 99 100 struct midi_hw_if_ext midisyn_hw_if_ext = { 101 .channel = midisyn_channelmsg, 102 .common = midisyn_commonmsg, 103 .sysex = midisyn_sysex, 104 }; 105 106 struct channelstate { /* dyamically allocated in open() on account of size */ 107 /* volume state components in centibels; just sum for overall level */ 108 int16_t volume; 109 int16_t expression; 110 /* pitch state components in midipitch units; sum for overall effect */ 111 midipitch_t bend; 112 midipitch_t tuning_fine; 113 midipitch_t tuning_coarse; 114 /* used by bend handlers */ 115 int16_t bendraw; 116 int16_t pendingreset; 117 /* rearrange as more controls supported - 16 bits should last for a while */ 118 #define PEND_VOL 1 119 #define PEND_EXP 2 120 #define PEND_LEVEL (PEND_VOL|PEND_EXP) 121 #define PEND_PBS 4 122 #define PEND_TNF 8 123 #define PEND_TNC 16 124 #define PEND_PITCH (PEND_PBS|PEND_TNF|PEND_TNC) 125 #define PEND_ALL (PEND_LEVEL|PEND_PITCH) 126 }; 127 128 static int 129 midisyn_open(void *addr, int flags, void (*iintr)(void *, int), 130 void (*ointr)(void *), void *arg) 131 { 132 midisyn *ms = addr; 133 int rslt, error; 134 uint_fast8_t chan; 135 136 KASSERT(ms->lock != NULL); 137 KASSERT(mutex_owned(ms->lock)); 138 DPRINTF(("midisyn_open: ms=%p ms->mets=%p\n", ms, ms->mets)); 139 140 mutex_exit(ms->lock); 141 ms->ctl.lock = ms->lock; 142 error = midictl_open(&ms->ctl); 143 if (error != 0) { 144 mutex_enter(ms->lock); 145 return error; 146 } 147 ms->chnstate = kmem_alloc(MIDI_MAX_CHANS * sizeof(*ms->chnstate), 148 KM_SLEEP); /* init'd by RESET below */ 149 mutex_enter(ms->lock); 150 151 rslt = 0; 152 if (ms->mets->open) 153 rslt = (ms->mets->open(ms, flags)); 154 155 /* 156 * Make the right initial things happen by faking receipt of RESET on 157 * all channels. The hw driver's ctlnotice() will be called in turn. 158 */ 159 for ( chan = 0 ; chan < MIDI_MAX_CHANS ; ++ chan ) 160 midisyn_notify(ms, MIDICTL_RESET, chan, 0); 161 162 return rslt; 163 } 164 165 static void 166 midisyn_close(void *addr) 167 { 168 midisyn *ms = addr; 169 struct midisyn_methods *fs; 170 int chan; 171 172 KASSERT(mutex_owned(ms->lock)); 173 DPRINTF(("midisyn_close: ms=%p ms->mets=%p\n", ms, ms->mets)); 174 fs = ms->mets; 175 176 for (chan = 0; chan < MIDI_MAX_CHANS; chan++) 177 midisyn_notify(ms, MIDICTL_SOUND_OFF, chan, 0); 178 179 if (fs->close) 180 fs->close(ms); 181 182 mutex_exit(ms->lock); 183 midictl_close(&ms->ctl); 184 kmem_free(ms->chnstate, MIDI_MAX_CHANS * sizeof(*ms->chnstate)); 185 mutex_enter(ms->lock); 186 } 187 188 static void 189 midisyn_getinfo(void *addr, struct midi_info *mi) 190 { 191 midisyn *ms = addr; 192 193 KASSERT(mutex_owned(ms->lock)); 194 195 mi->name = ms->name; 196 /* 197 * I was going to add a property here to suppress midi(4)'s warning 198 * about an output device that uses no transmit interrupt, on the 199 * assumption that as an onboard synth we handle "output" internally 200 * with nothing like the 320 us per byte busy wait of a dumb UART. 201 * Then I noticed that opl (at least as currently implemented) seems 202 * to need 40 us busy wait to set each register on an OPL2, and sets 203 * about 21 registers for every note-on. (Half of that is patch loading 204 * and could probably be reduced by different management of voices and 205 * patches.) For now I won't bother suppressing that warning.... 206 */ 207 mi->props = 0; 208 209 midi_register_hw_if_ext(&midisyn_hw_if_ext); 210 } 211 212 static void 213 midisyn_get_locks(void *addr, kmutex_t **intr, kmutex_t **proc) 214 { 215 midisyn *ms = addr; 216 217 *intr = ms->lock; 218 *proc = NULL; 219 } 220 221 static int 222 midisyn_ioctl(void *maddr, u_long cmd, void *addr, int flag, struct lwp *l) 223 { 224 midisyn *ms = maddr; 225 226 KASSERT(mutex_owned(ms->lock)); 227 228 if (ms->mets->ioctl) 229 return (ms->mets->ioctl(ms, cmd, addr, flag, l)); 230 else 231 return (EINVAL); 232 } 233 234 static int 235 midisyn_findvoice(midisyn *ms, int chan, int note) 236 { 237 u_int cn; 238 int v; 239 240 KASSERT(mutex_owned(ms->lock)); 241 242 cn = MS_CHANNOTE(chan, note); 243 for (v = 0; v < ms->nvoice; v++) 244 if (ms->voices[v].chan_note == cn && ms->voices[v].inuse) 245 return (v); 246 return (-1); 247 } 248 249 void 250 midisyn_init(midisyn *ms) 251 { 252 253 KASSERT(ms->lock != NULL); 254 255 /* 256 * XXX there should be a way for this function to indicate failure 257 * (other than panic) if some preconditions aren't met, for example 258 * if some nonoptional methods are missing. 259 */ 260 if (ms->mets->allocv == 0) { 261 ms->voices = kmem_zalloc(ms->nvoice * sizeof(struct voice), 262 KM_SLEEP); 263 ms->seqno = 1; 264 ms->mets->allocv = midisyn_allocvoice; 265 } 266 267 if (ms->mets->attackv_vel == 0 && ms->mets->attackv != 0) 268 ms->mets->attackv_vel = midisyn_attackv_vel; 269 270 ms->ctl = (midictl) { 271 .base_channel = 16, 272 .cookie = ms, 273 .notify = midisyn_notify 274 }; 275 276 DPRINTF(("midisyn_init: ms=%p\n", ms)); 277 } 278 279 static void 280 midisyn_freevoice(midisyn *ms, int voice) 281 { 282 283 KASSERT(mutex_owned(ms->lock)); 284 285 if (ms->mets->allocv != midisyn_allocvoice) 286 return; 287 ms->voices[voice].inuse = 0; 288 } 289 290 static uint_fast16_t 291 midisyn_allocvoice(midisyn *ms, uint_fast8_t chan, uint_fast8_t note) 292 { 293 int bestv, v; 294 u_int bestseq, s; 295 296 KASSERT(mutex_owned(ms->lock)); 297 298 /* Find a free voice, or if no free voice is found the oldest. */ 299 bestv = 0; 300 bestseq = ms->voices[0].seqno + (ms->voices[0].inuse ? 0x40000000 : 0); 301 for (v = 1; v < ms->nvoice; v++) { 302 s = ms->voices[v].seqno; 303 if (ms->voices[v].inuse) 304 s += 0x40000000; 305 if (s < bestseq) { 306 bestseq = s; 307 bestv = v; 308 } 309 } 310 DPRINTFN(10,("midisyn_allocvoice: v=%d seq=%d cn=%x inuse=%d\n", 311 bestv, ms->voices[bestv].seqno, 312 ms->voices[bestv].chan_note, 313 ms->voices[bestv].inuse)); 314 #ifdef AUDIO_DEBUG 315 if (ms->voices[bestv].inuse) 316 DPRINTFN(1,("midisyn_allocvoice: steal %x\n", 317 ms->voices[bestv].chan_note)); 318 #endif 319 ms->voices[bestv].chan_note = MS_CHANNOTE(chan, note); 320 ms->voices[bestv].seqno = ms->seqno++; 321 ms->voices[bestv].inuse = 1; 322 return (bestv); 323 } 324 325 /* dummy attackv_vel that just adds vel into level for simple drivers */ 326 static void 327 midisyn_attackv_vel(midisyn *ms, uint_fast16_t voice, midipitch_t mp, 328 int16_t level_cB, uint_fast8_t vel) 329 { 330 331 KASSERT(mutex_owned(ms->lock)); 332 333 ms->voices[voice].velcB = midisyn_vol2cB((uint_fast16_t)vel << 7); 334 ms->mets->attackv(ms, voice, mp, level_cB + ms->voices[voice].velcB); 335 } 336 337 static int 338 midisyn_sysrt(void *addr, int b) 339 { 340 341 return 0; 342 } 343 344 static int 345 midisyn_channelmsg(void *addr, int status, int chan, u_char *buf, int len) 346 { 347 midisyn *ms = addr; 348 int voice = 0; /* initialize to keep gcc quiet */ 349 struct midisyn_methods *fs; 350 351 KASSERT(mutex_owned(ms->lock)); 352 353 DPRINTF(("midisyn_channelmsg: ms=%p status=%#02x chan=%d\n", 354 ms, status, chan)); 355 fs = ms->mets; 356 357 switch (status) { 358 case MIDI_NOTEOFF: 359 /* 360 * for a device that leaves voice allocation to us--and that's 361 * all of 'em at the moment--the voice and release velocity 362 * should be the only necessary arguments to noteoff. what use 363 * are they making of note? checking... None. Cool. 364 * IF there is ever a device added that does its own allocation, 365 * extend the interface; this findvoice won't be what to do... 366 */ 367 voice = midisyn_findvoice(ms, chan, buf[1]); 368 if (voice >= 0) { 369 fs->releasev(ms, voice, buf[2]); 370 midisyn_freevoice(ms, voice); 371 } 372 break; 373 case MIDI_NOTEON: 374 /* 375 * what's called for here, given current drivers, is an i/f 376 * where midisyn computes a volume from vel*volume*expression* 377 * mastervolume and passes that result as a single arg. It can 378 * evolve later to support drivers that expose some of those 379 * bits separately (e.g. a driver could expose a mixer register 380 * on its sound card and use that for mastervolume). 381 */ 382 voice = fs->allocv(ms, chan, buf[1]); 383 ms->voices[voice].velcB = 0; /* assume driver handles vel */ 384 fs->attackv_vel(ms, voice, 385 midisyn_clamp_pitch(MIDIPITCH_FROM_KEY(buf[1]) + 386 midisyn_adj_pitch(ms, chan)), 387 midisyn_adj_level(ms,chan), buf[2]); 388 break; 389 case MIDI_KEY_PRESSURE: 390 /* 391 * unimplemented by the existing drivers. if we are doing 392 * voice allocation, find the voice that corresponds to this 393 * chan/note and define a method that passes the voice and 394 * pressure to the driver ... not the note, /it/ doesn't matter. 395 * For a driver that does its own allocation, a different 396 * method may be needed passing pressure, chan, note so it can 397 * find the right voice on its own. Be sure that whatever is 398 * done here is undone when midisyn_notify sees MIDICTL_RESET. 399 */ 400 break; 401 case MIDI_CTL_CHANGE: 402 midictl_change(&ms->ctl, chan, buf+1); 403 break; 404 case MIDI_PGM_CHANGE: 405 if (fs->pgmchg) 406 fs->pgmchg(ms, chan, buf[1]); 407 break; 408 case MIDI_CHN_PRESSURE: 409 /* 410 * unimplemented by the existing drivers. if driver exposes no 411 * distinct method, can use KEY_PRESSURE method for each voice 412 * on channel. Be sure that whatever is 413 * done here is undone when midisyn_notify sees MIDICTL_RESET. 414 */ 415 break; 416 case MIDI_PITCH_BEND: 417 /* 418 * Will work for most drivers that simply render the midipitch 419 * as we pass it (but not cms, which chops all the bits after 420 * the note number and then computes its own pitch :( ). If the 421 * driver has a repitchv method for voices already sounding, so 422 * much the better. 423 * The bending logic lives in the handler for bend sensitivity, 424 * so fake a change to that to kick it off. 425 */ 426 ms->chnstate[chan].bendraw = buf[2]<<7 | buf[1]; 427 ms->chnstate[chan].bendraw -= MIDI_BEND_NEUTRAL; 428 midisyn_notify(ms, MIDICTL_RPN, chan, 429 MIDI_RPN_PITCH_BEND_SENSITIVITY); 430 break; 431 } 432 return 0; 433 } 434 435 static int 436 midisyn_commonmsg(void *addr, int status, u_char *buf, int len) 437 { 438 439 return 0; 440 } 441 442 static int 443 midisyn_sysex(void *addr, u_char *buf, int len) 444 { 445 446 /* 447 * unimplemented by existing drivers. it is surely more sensible 448 * to do some parsing of well-defined sysex messages here, either 449 * handling them internally or calling specific methods on the 450 * driver after parsing out the details, than to ask every driver 451 * to deal with sysex messages poked at it a byte at a time. 452 */ 453 return 0; 454 } 455 456 static void 457 midisyn_notify(void *cookie, midictl_evt evt, 458 uint_fast8_t chan, uint_fast16_t key) 459 { 460 struct midisyn *ms; 461 int drvhandled; 462 463 ms = (struct midisyn *)cookie; 464 465 KASSERT(mutex_owned(ms->lock)); 466 467 drvhandled = 0; 468 if ( ms->mets->ctlnotice ) 469 drvhandled = ms->mets->ctlnotice(ms, evt, chan, key); 470 471 switch ( evt | key ) { 472 case MIDICTL_RESET: 473 /* 474 * Re-read all ctls we use, revert pitchbend state. 475 * Can do it by faking change notifications. 476 */ 477 ms->chnstate[chan].pendingreset |= PEND_ALL; 478 midisyn_notify(ms, MIDICTL_CTLR, chan, 479 MIDI_CTRL_CHANNEL_VOLUME_MSB); 480 midisyn_notify(ms, MIDICTL_CTLR, chan, 481 MIDI_CTRL_EXPRESSION_MSB); 482 ms->chnstate[chan].bendraw = 0; /* MIDI_BEND_NEUTRAL - itself */ 483 midisyn_notify(ms, MIDICTL_RPN, chan, 484 MIDI_RPN_PITCH_BEND_SENSITIVITY); 485 midisyn_notify(ms, MIDICTL_RPN, chan, 486 MIDI_RPN_CHANNEL_FINE_TUNING); 487 midisyn_notify(ms, MIDICTL_RPN, chan, 488 MIDI_RPN_CHANNEL_COARSE_TUNING); 489 break; 490 case MIDICTL_NOTES_OFF: 491 if ( drvhandled ) 492 break; 493 /* releasev all voices sounding on chan; use normal vel 64 */ 494 midisyn_chan_releasev(ms, chan, 64); 495 break; 496 case MIDICTL_SOUND_OFF: 497 if ( drvhandled ) 498 break; 499 /* releasev all voices sounding on chan; use max vel 127 */ 500 /* it is really better for driver to handle this, instantly */ 501 midisyn_chan_releasev(ms, chan, 127); 502 break; 503 case MIDICTL_CTLR | MIDI_CTRL_CHANNEL_VOLUME_MSB: 504 ms->chnstate[chan].pendingreset &= ~PEND_VOL; 505 if ( drvhandled ) { 506 ms->chnstate[chan].volume = 0; 507 break; 508 } 509 ms->chnstate[chan].volume = midisyn_vol2cB( 510 midictl_read(&ms->ctl, chan, key, 100<<7)); 511 midisyn_upd_level(ms, chan); 512 break; 513 case MIDICTL_CTLR | MIDI_CTRL_EXPRESSION_MSB: 514 ms->chnstate[chan].pendingreset &= ~PEND_EXP; 515 if ( drvhandled ) { 516 ms->chnstate[chan].expression = 0; 517 break; 518 } 519 ms->chnstate[chan].expression = midisyn_vol2cB( 520 midictl_read(&ms->ctl, chan, key, 16383)); 521 midisyn_upd_level(ms, chan); 522 break; 523 /* 524 * SOFT_PEDAL: supporting this will be trickier; must apply only 525 * to notes subsequently struck, and must remember which voices 526 * they are for follow-on adjustments. For another day.... 527 */ 528 case MIDICTL_RPN | MIDI_RPN_PITCH_BEND_SENSITIVITY: 529 ms->chnstate[chan].pendingreset &= ~PEND_PBS; 530 if ( drvhandled ) 531 ms->chnstate[chan].bend = 0; 532 else { 533 uint16_t w; 534 int8_t semis, cents; 535 w = midictl_rpn_read(&ms->ctl, chan, key, 2<<7); 536 semis = w>>7; 537 cents = w&0x7f; 538 /* 539 * Mathematically, multiply semis by 540 * MIDIPITCH_SEMITONE*bendraw/8192. Practically, avoid 541 * shifting significant bits off by observing that 542 * MIDIPITCH_SEMITONE == 1<<14 and 8192 == 1<<13, so 543 * just take semis*bendraw<<1. Do the same with cents 544 * except <<1 becomes /50 (but rounded). 545 */ 546 ms->chnstate[chan].bend = 547 ( ms->chnstate[chan].bendraw * semis ) << 1; 548 ms->chnstate[chan].bend += 549 ((ms->chnstate[chan].bendraw * cents)/25 + 1) >> 1; 550 midisyn_upd_pitch(ms, chan); 551 } 552 break; 553 case MIDICTL_RPN | MIDI_RPN_CHANNEL_FINE_TUNING: 554 if ( drvhandled ) 555 ms->chnstate[chan].tuning_fine = 0; 556 else { 557 midipitch_t mp; 558 mp = midictl_rpn_read(&ms->ctl, chan, key, 8192); 559 /* 560 * Mathematically, subtract 8192 and scale by 561 * MIDIPITCH_SEMITONE/8192. Practically, subtract 8192 562 * and then << 1. 563 */ 564 ms->chnstate[chan].tuning_fine = ( mp - 8192 ) << 1; 565 midisyn_upd_pitch(ms, chan); 566 } 567 break; 568 case MIDICTL_RPN | MIDI_RPN_CHANNEL_COARSE_TUNING: 569 ms->chnstate[chan].pendingreset &= ~PEND_TNC; 570 if ( drvhandled ) 571 ms->chnstate[chan].tuning_coarse = 0; 572 else { 573 midipitch_t mp; 574 /* 575 * By definition only the MSB of this parameter is used. 576 * Subtract 64 for a signed count of semitones; << 14 577 * will convert to midipitch scale. 578 */ 579 mp = midictl_rpn_read(&ms->ctl, chan, key, 64<<7) >> 7; 580 ms->chnstate[chan].tuning_coarse = ( mp - 64 ) << 14; 581 midisyn_upd_pitch(ms, chan); 582 } 583 break; 584 } 585 } 586 587 static midipitch_t 588 midisyn_clamp_pitch(midipitch_t mp) 589 { 590 591 if ( mp <= 0 ) 592 return 0; 593 if ( mp >= MIDIPITCH_MAX ) 594 return MIDIPITCH_MAX; 595 return mp; 596 } 597 598 static int16_t 599 midisyn_adj_level(midisyn *ms, uint_fast8_t chan) 600 { 601 int32_t level; 602 603 KASSERT(mutex_owned(ms->lock)); 604 605 level = ms->chnstate[chan].volume + ms->chnstate[chan].expression; 606 if ( level <= INT16_MIN ) 607 return INT16_MIN; 608 return level; 609 } 610 611 static midipitch_t 612 midisyn_adj_pitch(midisyn *ms, uint_fast8_t chan) 613 { 614 struct channelstate *s = ms->chnstate + chan; 615 616 KASSERT(mutex_owned(ms->lock)); 617 618 return s->bend + s->tuning_fine +s->tuning_coarse; 619 } 620 621 #define VOICECHAN_FOREACH_BEGIN(ms,vp,ch) \ 622 { \ 623 struct voice *vp, *_end_##vp; \ 624 for (vp=(ms)->voices,_end_##vp=vp+(ms)->nvoice; \ 625 vp < _end_##vp; ++ vp) { \ 626 if ( !vp->inuse ) \ 627 continue; \ 628 if ( MS_GETCHAN(vp) == (ch) ) \ 629 ; \ 630 else \ 631 continue; 632 #define VOICECHAN_FOREACH_END }} 633 634 static void 635 midisyn_chan_releasev(midisyn *ms, uint_fast8_t chan, uint_fast8_t vel) 636 { 637 638 KASSERT(mutex_owned(ms->lock)); 639 640 VOICECHAN_FOREACH_BEGIN(ms,vp,chan) 641 ms->mets->releasev(ms, vp - ms->voices, vel); 642 midisyn_freevoice(ms, vp - ms->voices); 643 VOICECHAN_FOREACH_END 644 } 645 646 static void 647 midisyn_upd_level(midisyn *ms, uint_fast8_t chan) 648 { 649 int32_t level; 650 int16_t chan_level; 651 652 KASSERT(mutex_owned(ms->lock)); 653 654 if ( NULL == ms->mets->relevelv ) 655 return; 656 657 if ( ms->chnstate[chan].pendingreset & PEND_LEVEL ) 658 return; 659 660 chan_level = midisyn_adj_level(ms, chan); 661 662 VOICECHAN_FOREACH_BEGIN(ms,vp,chan) 663 level = vp->velcB + chan_level; 664 ms->mets->relevelv(ms, vp - ms->voices, 665 level <= INT16_MIN ? INT16_MIN : level); 666 VOICECHAN_FOREACH_END 667 } 668 669 static void 670 midisyn_upd_pitch(midisyn *ms, uint_fast8_t chan) 671 { 672 midipitch_t chan_adj; 673 674 KASSERT(mutex_owned(ms->lock)); 675 676 if ( NULL == ms->mets->repitchv ) 677 return; 678 679 if ( ms->chnstate[chan].pendingreset & PEND_PITCH ) 680 return; 681 682 chan_adj = midisyn_adj_pitch(ms, chan); 683 684 VOICECHAN_FOREACH_BEGIN(ms,vp,chan) 685 ms->mets->repitchv(ms, vp - ms->voices, 686 midisyn_clamp_pitch(chan_adj + 687 MIDIPITCH_FROM_KEY(vp->chan_note&0x7f))); 688 VOICECHAN_FOREACH_END 689 } 690 691 #undef VOICECHAN_FOREACH_END 692 #undef VOICECHAN_FOREACH_BEGIN 693 694 int16_t 695 midisyn_vol2cB(uint_fast16_t vol) 696 { 697 int16_t cB = 0; 698 int32_t v; 699 700 if ( 0 == vol ) 701 return INT16_MIN; 702 /* 703 * Adjust vol to fall in the range 8192..16383. Each doubling is 704 * worth 12 dB. 705 */ 706 while ( vol < 8192 ) { 707 vol <<= 1; 708 cB -= 120; 709 } 710 v = vol; /* ensure evaluation in signed 32 bit below */ 711 /* 712 * The GM vol-to-dB formula is dB = 40 log ( v / 127 ) for 7-bit v. 713 * The vol and expression controllers are in 14-bit space so the 714 * equivalent is 40 log ( v / 16256 ) - that is, MSB 127 LSB 0 because 715 * the LSB is commonly unused. MSB 127 LSB 127 would then be a tiny 716 * bit over. 717 * 1 dB resolution is a little coarser than we'd like, so let's shoot 718 * for centibels, i.e. 400 log ( v / 16256 ), and shift everything left 719 * as far as will fit in 32 bits, which turns out to be a shift of 22. 720 * This minimax polynomial approximation is good to about a centibel 721 * on the range 8192..16256, a shade worse (1.4 or so) above that. 722 * 26385/10166 is the 6th convergent of the coefficient for v^2. 723 */ 724 cB += ( v * ( 124828 - ( v * 26385 ) / 10166 ) - 1347349038 ) >> 22; 725 return cB; 726 } 727 728 /* 729 * MIDI RP-012 constitutes a MIDI Tuning Specification. The units are 730 * fractional-MIDIkeys, that is, the key number 00 - 7f left shifted 731 * 14 bits to provide a 14-bit fraction that divides each semitone. The 732 * whole thing is just a 21-bit number that is bent and tuned simply by 733 * adding and subtracting--the same offset is the same pitch change anywhere 734 * on the scale. One downside is that a cent is 163.84 of these units, so 735 * you can't expect a lengthy integer sum of cents to come out in tune; if you 736 * do anything in cents it is best to use them only for local adjustment of 737 * a pitch. 738 * 739 * This function converts a pitch in MIDItune units to Hz left-shifted 18 bits. 740 * That should leave you enough to shift down to whatever precision the hardware 741 * supports. 742 * 743 * Its prototype is exposed in <sys/midiio.h>. 744 */ 745 midihz18_t 746 midisyn_mp2hz18(midipitch_t mp) 747 { 748 int64_t t64a, t64b; 749 uint_fast8_t shift; 750 751 /* 752 * Scale from the logarithmic MIDI-Tuning units to Hz<<18. Uses the 753 * continued-fraction form of a 2/2 rational function derived to 754 * cover the highest octave (mt 1900544..2097151 or 74.00.00..7f.7f.7f 755 * in RP-012-speak, the dotted bits are 7 wide) to produce Hz shifted 756 * left just as far as the maximum Hz will fit in a uint32, which 757 * turns out to be 18. Just shift off the result for lower octaves. 758 * Fit is within 1/4 MIDI tuning unit throughout (disclaimer: the 759 * comparison relied on the double-precision log in libm). 760 */ 761 762 if ( 0 == mp ) 763 return 2143236; 764 765 for ( shift = 0; mp < 1900544; ++ shift ) 766 mp += MIDIPITCH_OCTAVE; 767 768 if ( 1998848 == mp ) 769 return UINT32_C(2463438621) >> shift; 770 771 t64a = 0x5a1a0ee4; /* INT64_C(967879298788) gcc333: spurious warning */ 772 t64a |= (int64_t)0xe1 << 32; 773 t64a /= mp - 1998848; /* here's why 1998848 is special-cased above ;) */ 774 t64a += mp - 3704981; 775 t64b = 0x6763759d; /* INT64_C(8405905567872413) goofy warning again */ 776 t64b |= (int64_t)0x1ddd20 << 32; 777 t64b /= t64a; 778 t64b += UINT32_C(2463438619); 779 return (uint32_t)t64b >> shift; 780 } 781
Indexes created Sat Sep 20 22:09:52 GMT 2025