| 1 | /* $NetBSD: midisynvar.h,v 1.14 2012/04/09 10:18:16 plunky 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 | |
| 37 | typedef 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 | */ |
| 51 | struct 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 | |
| 147 | struct 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 | |
| 158 | struct channelstate; |
| 159 | |
| 160 | struct 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 | |
| 187 | extern const struct midi_hw_if midisyn_hw_if; |
| 188 | |
| 189 | void 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 | */ |
| 198 | extern int16_t midisyn_vol2cB(uint_fast16_t); |
| 199 | |
| 200 | #endif /* _SYS_DEV_MIDISYNVAR_H_ */ |
| 201 | |