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 | |