1/* $NetBSD: midisynvar.h,v 1.13 2011/11/23 23:07:31 jmcneill 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@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 * 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#ifndef _SYS_DEV_MIDISYNVAR_H_ 33#define _SYS_DEV_MIDISYNVAR_H_ 34 35#include "midictl.h" 36 37typedef struct midisyn midisyn; 38 39/* 40 * Important: any synth driver that uses midisyn must set up its methods 41 * structure in a way that refers to members /by name/ and zeroes the rest 42 * (as is the effect of C99 initializers with designators). This discipline 43 * will allow the structure to evolve methods for newly implemented 44 * functionality or to exploit capabilities of new drivers with a minimal 45 * versioning burden. Because midisyn is at present a very rudimentary and 46 * partial implementation, change should be expected in this set of methods. 47 * Do not hesitate to add one in the course of implementing new stuff, as 48 * long as it will be generally useful and there is some reasonable fallback 49 * for drivers without it. 50 */ 51struct midisyn_methods { 52 int (*open) (midisyn *, int /* flags */); 53 void (*close) (midisyn *); 54 int (*ioctl) (midisyn *, u_long, void *, int, struct lwp *); 55 /* 56 * allocv(midisyn *ms, uint_fast8_t chan, uint_fast8_t key); 57 * Allocate one of the devices actual voices (stealing one if 58 * necessary) to play note number 'key' (the MIDI note number, not 59 * a frequency) associated with MIDI channel chan. An implementation 60 * might want to choose a voice already last used on chan, to save 61 * shuffling of patches. 62 * One day a variant of this method will probably be needed, with an 63 * extra argument indicating whether a melodic or percussive voice is 64 * wanted. 65 */ 66 uint_fast16_t (*allocv) (midisyn *, uint_fast8_t, uint_fast8_t); 67 /* 68 * attackv(midisyn *ms, 69 * uint_fast16_t voice, midipitch_t mp, int16_t level_cB); 70 * Attack the voice 'voice' at pitch 'midipitch' with level 'level_cB'. 71 * The pitch is in MIDI Tuning units and accounts for all of the pitch 72 * adjustment controls that midisyn supports and that the driver has 73 * not reported handling internally. The level is in centibels of 74 * attenuation (0 == no attenuation, full output; reduced levels are 75 * negative) and again accounts for all level adjustments midisyn 76 * supports, except any the driver reports handling itself. 77 * The program used for the voice should be the current program of the 78 * voice's associated MIDI channel, and can be queried with MS_GETPGM. 79 */ 80 void (*attackv) (midisyn *, uint_fast16_t, midipitch_t, int16_t); 81 /* 82 * attackv_vel(midisyn *ms, uint_fast16_t voice, 83 * midipitch_t mp, int16_t level_cB, uint_fast8_t vel); 84 * If the driver can do something useful with the voice's attack 85 * velocity, such as vary the attack envelope or timbre, it should 86 * provide this method. Velocity 64 represents the normal attack for 87 * the patch, lower values are softer, higher harder. IF the driver 88 * does not supply this method, midisyn will call the attackv method 89 * instead, and include the velocity in the calculation of level_cB. 90 */ 91 void (*attackv_vel) (midisyn *, 92 uint_fast16_t, midipitch_t, int16_t, uint_fast8_t); 93 /* 94 * releasev(midisyn *ms, uint_fast16_t voice, uint_fast8_t vel); 95 * Release the voice 'voice' with release velocity 'vel' where lower 96 * values mean slower decay, 64 refers to the normal decay envelope 97 * for the patch, and higher values mean decay faster. 98 */ 99 void (*releasev) (midisyn *, uint_fast16_t, uint_fast8_t); 100 /* 101 * repitchv(midisyn *ms, uint_fast16_t voice, midipitch_t mp); 102 * A driver should provide this method if it is able to change the 103 * pitch of a sounding voice without rearticulating or glitching it. 104 * [not yet implemented in midisyn] 105 */ 106 void (*repitchv) (midisyn *, uint_fast16_t, midipitch_t); 107 /* 108 * relevelv(midisyn *ms, uint_fast16_t voice, int16_t level_cB); 109 * A driver should provide this method if it is able to change the 110 * level of a sounding voice without rearticulating or glitching it. 111 * How the driver should adjust 'level_cB' to account for envelope 112 * decay since the initial level is not (quite, yet) specified; the 113 * driver may save the last level it got from midisyn, subtract from 114 * this one, and use the difference to adjust the current level out of 115 * the envelope generator. Or not.... [not yet implemented in midisyn] 116 */ 117 void (*relevelv) (midisyn *, uint_fast16_t, int16_t); 118 /* 119 * pgmchg(midisyn *ms, uint_fast8_t chan, uint_fast8_t pgm); 120 * If the driver supports changing programs, it should do whatever it 121 * does AND be sure to store pgm in ms->pgms[chan]. (XXX?) 122 */ 123 void (*pgmchg) (midisyn *, uint_fast8_t, uint_fast8_t); 124 /* 125 * ctlnotice(midisyn *ms, 126 * midictl_evt evt, uint_fast8_t chan, uint_fast16_t key); 127 * Reports any of the events on channel 'chan' that midictl (which see) 128 * manages. Return 0 for a particular event if it is not handled by the 129 * driver, nonzero if the driver handles it. Many events can be handled 130 * by midisyn if the driver ignores them, but will be left to the driver 131 * if it returns non-zero. For example, midisyn will usually combine 132 * the volume and expression controllers, plus a note's attack velocity, 133 * into a single 'level' parameter to attackv, but if the driver is 134 * responding to the volume controller on its own, midisyn will leave 135 * that controller out of the combined level computation. 136 * The driver should respond to MIDICTL_RESET events specially. There 137 * are some items of state other than controllers that are specified to 138 * be reset; if the driver keeps such state, it should be reset. The 139 * driver should also midictl_read() all controllers it can respond to, 140 * which will ensure that midictl tracks them. 141 * There are also things that RP-015 specifies do NOT get reset by 142 * the MIDICTL_RESET event. Don't reset those. :) 143 */ 144 int (*ctlnotice) (midisyn *, midictl_evt, uint_fast8_t, uint_fast16_t); 145}; 146 147struct voice { 148 u_int chan_note; /* channel and note */ 149#define MS_CHANNOTE(chan, note) ((chan) * 256 + (note)) 150#define MS_GETCHAN(v) ((v)->chan_note >> 8) 151 u_int seqno; /* allocation index (increases with time) */ 152 int16_t velcB; /* cB based on attack vel (relevel may need) */ 153 u_char inuse; 154}; 155 156#define MIDI_MAX_CHANS 16 157 158struct channelstate; 159 160struct midisyn { 161 /* Filled by synth driver */ 162 struct midisyn_methods *mets; 163 char name[32]; 164 int nvoice; 165 int flags; 166 void *data; 167 kmutex_t *lock; 168 169 /* Set up by midisyn but available to synth driver for reading ctls */ 170 /* 171 * Note - there is currently no locking on this structure; if the synth 172 * driver interacts with midictl it should do so synchronously, when 173 * processing a call from midisyn, and not at other times such as upon 174 * an interrupt. (may revisit locking if problems crop up.) 175 */ 176 midictl ctl; 177 178 /* Used by midisyn driver */ 179 struct voice *voices; 180 u_int seqno; 181 u_int16_t pgms[MIDI_MAX_CHANS]; /* ref'd if driver uses MS_GETPGM */ 182 struct channelstate *chnstate; 183}; 184 185#define MS_GETPGM(ms, vno) ((ms)->pgms[MS_GETCHAN(&(ms)->voices[vno])]) 186 187extern const struct midi_hw_if midisyn_hw_if; 188 189void midisyn_init(midisyn *); 190 191/* 192 * Convert a 14-bit volume or expression controller value to centibels using 193 * the General MIDI formula. The maximum controller value translates to 0 cB 194 * (no attenuation), a half-range controller to -119 cB (level cut by 11.9 dB) 195 * and a zero controller to INT16_MIN. If you are converting a 7-bit value 196 * just shift it 7 bits left first. 197 */ 198extern int16_t midisyn_vol2cB(uint_fast16_t); 199 200#endif /* _SYS_DEV_MIDISYNVAR_H_ */ 201