/* $NetBSD: midisynvar.h,v 1.14 2012/04/09 10:18:16 plunky Exp $ */
/*
* Copyright (c) 1998 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Lennart Augustsson (augustss@NetBSD.org).
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _SYS_DEV_MIDISYNVAR_H_
#define _SYS_DEV_MIDISYNVAR_H_
#include "midictl.h"
typedef struct midisyn midisyn;
/*
* Important: any synth driver that uses midisyn must set up its methods
* structure in a way that refers to members /by name/ and zeroes the rest
* (as is the effect of C99 initializers with designators). This discipline
* will allow the structure to evolve methods for newly implemented
* functionality or to exploit capabilities of new drivers with a minimal
* versioning burden. Because midisyn is at present a very rudimentary and
* partial implementation, change should be expected in this set of methods.
* Do not hesitate to add one in the course of implementing new stuff, as
* long as it will be generally useful and there is some reasonable fallback
* for drivers without it.
*/
struct midisyn_methods {
int (*open) (midisyn *, int /* flags */);
void (*close) (midisyn *);
int (*ioctl) (midisyn *, u_long, void *, int, struct lwp *);
/*
* allocv(midisyn *ms, uint_fast8_t chan, uint_fast8_t key);
* Allocate one of the devices actual voices (stealing one if
* necessary) to play note number 'key' (the MIDI note number, not
* a frequency) associated with MIDI channel chan. An implementation
* might want to choose a voice already last used on chan, to save
* shuffling of patches.
* One day a variant of this method will probably be needed, with an
* extra argument indicating whether a melodic or percussive voice is
* wanted.
*/
uint_fast16_t (*allocv) (midisyn *, uint_fast8_t, uint_fast8_t);
/*
* attackv(midisyn *ms,
* uint_fast16_t voice, midipitch_t mp, int16_t level_cB);
* Attack the voice 'voice' at pitch 'midipitch' with level 'level_cB'.
* The pitch is in MIDI Tuning units and accounts for all of the pitch
* adjustment controls that midisyn supports and that the driver has
* not reported handling internally. The level is in centibels of
* attenuation (0 == no attenuation, full output; reduced levels are
* negative) and again accounts for all level adjustments midisyn
* supports, except any the driver reports handling itself.
* The program used for the voice should be the current program of the
* voice's associated MIDI channel, and can be queried with MS_GETPGM.
*/
void (*attackv) (midisyn *, uint_fast16_t, midipitch_t, int16_t);
/*
* attackv_vel(midisyn *ms, uint_fast16_t voice,
* midipitch_t mp, int16_t level_cB, uint_fast8_t vel);
* If the driver can do something useful with the voice's attack
* velocity, such as vary the attack envelope or timbre, it should
* provide this method. Velocity 64 represents the normal attack for
* the patch, lower values are softer, higher harder. IF the driver
* does not supply this method, midisyn will call the attackv method
* instead, and include the velocity in the calculation of level_cB.
*/
void (*attackv_vel) (midisyn *,
uint_fast16_t, midipitch_t, int16_t, uint_fast8_t);
/*
* releasev(midisyn *ms, uint_fast16_t voice, uint_fast8_t vel);
* Release the voice 'voice' with release velocity 'vel' where lower
* values mean slower decay, 64 refers to the normal decay envelope
* for the patch, and higher values mean decay faster.
*/
void (*releasev) (midisyn *, uint_fast16_t, uint_fast8_t);
/*
* repitchv(midisyn *ms, uint_fast16_t voice, midipitch_t mp);
* A driver should provide this method if it is able to change the
* pitch of a sounding voice without rearticulating or glitching it.
* [not yet implemented in midisyn]
*/
void (*repitchv) (midisyn *, uint_fast16_t, midipitch_t);
/*
* relevelv(midisyn *ms, uint_fast16_t voice, int16_t level_cB);
* A driver should provide this method if it is able to change the
* level of a sounding voice without rearticulating or glitching it.
* How the driver should adjust 'level_cB' to account for envelope
* decay since the initial level is not (quite, yet) specified; the
* driver may save the last level it got from midisyn, subtract from
* this one, and use the difference to adjust the current level out of
* the envelope generator. Or not.... [not yet implemented in midisyn]
*/
void (*relevelv) (midisyn *, uint_fast16_t, int16_t);
/*
* pgmchg(midisyn *ms, uint_fast8_t chan, uint_fast8_t pgm);
* If the driver supports changing programs, it should do whatever it
* does AND be sure to store pgm in ms->pgms[chan]. (XXX?)
*/
void (*pgmchg) (midisyn *, uint_fast8_t, uint_fast8_t);
/*
* ctlnotice(midisyn *ms,
* midictl_evt evt, uint_fast8_t chan, uint_fast16_t key);
* Reports any of the events on channel 'chan' that midictl (which see)
* manages. Return 0 for a particular event if it is not handled by the
* driver, nonzero if the driver handles it. Many events can be handled
* by midisyn if the driver ignores them, but will be left to the driver
* if it returns non-zero. For example, midisyn will usually combine
* the volume and expression controllers, plus a note's attack velocity,
* into a single 'level' parameter to attackv, but if the driver is
* responding to the volume controller on its own, midisyn will leave
* that controller out of the combined level computation.
* The driver should respond to MIDICTL_RESET events specially. There
* are some items of state other than controllers that are specified to
* be reset; if the driver keeps such state, it should be reset. The
* driver should also midictl_read() all controllers it can respond to,
* which will ensure that midictl tracks them.
* There are also things that RP-015 specifies do NOT get reset by
* the MIDICTL_RESET event. Don't reset those. :)
*/
int (*ctlnotice) (midisyn *, midictl_evt, uint_fast8_t, uint_fast16_t);
};
struct voice {
u_int chan_note; /* channel and note */
#define MS_CHANNOTE(chan, note) ((chan) * 256 + (note))
#define MS_GETCHAN(v) ((v)->chan_note >> 8)
u_int seqno; /* allocation index (increases with time) */
int16_t velcB; /* cB based on attack vel (relevel may need) */
u_char inuse;
};
#define MIDI_MAX_CHANS 16
struct channelstate;
struct midisyn {
/* Filled by synth driver */
struct midisyn_methods *mets;
char name[32];
int nvoice;
int flags;
void *data;
kmutex_t *lock;
/* Set up by midisyn but available to synth driver for reading ctls */
/*
* Note - there is currently no locking on this structure; if the synth
* driver interacts with midictl it should do so synchronously, when
* processing a call from midisyn, and not at other times such as upon
* an interrupt. (may revisit locking if problems crop up.)
*/
midictl ctl;
/* Used by midisyn driver */
struct voice *voices;
u_int seqno;
u_int16_t pgms[MIDI_MAX_CHANS]; /* ref'd if driver uses MS_GETPGM */
struct channelstate *chnstate;
};
#define MS_GETPGM(ms, vno) ((ms)->pgms[MS_GETCHAN(&(ms)->voices[vno])])
extern const struct midi_hw_if midisyn_hw_if;
void midisyn_init(midisyn *);
/*
* Convert a 14-bit volume or expression controller value to centibels using
* the General MIDI formula. The maximum controller value translates to 0 cB
* (no attenuation), a half-range controller to -119 cB (level cut by 11.9 dB)
* and a zero controller to INT16_MIN. If you are converting a 7-bit value
* just shift it 7 bits left first.
*/
extern int16_t midisyn_vol2cB(uint_fast16_t);
#endif /* _SYS_DEV_MIDISYNVAR_H_ */