emux_synth.c

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/*
 *  Midi synth routines for the Emu8k/Emu10k1
 *
 *  Copyright (C) 1999 Steve Ratcliffe
 *  Copyright (c) 1999-2000 Takashi Iwai <[email protected]>
 *
 *  Contains code based on awe_wave.c by Takashi Iwai
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 */

#include <linux/export.h>
#include "emux_voice.h"
#include <sound/asoundef.h>

/*
 * Prototypes
 */

/*
 * Ensure a value is between two points
 * macro evaluates its args more than once, so changed to upper-case.
 */
#define LIMITVALUE(x, a, b) do { if ((x) < (a)) (x) = (a); else if ((x) > (b)) (x) = (b); } while (0)
#define LIMITMAX(x, a) do {if ((x) > (a)) (x) = (a); } while (0)

static int get_zone(struct snd_emux *emu, struct snd_emux_port *port,
            int *notep, int vel, struct snd_midi_channel *chan,
            struct snd_sf_zone **table);
static int get_bank(struct snd_emux_port *port, struct snd_midi_channel *chan);
static void terminate_note1(struct snd_emux *emu, int note,
                struct snd_midi_channel *chan, int free);
static void exclusive_note_off(struct snd_emux *emu, struct snd_emux_port *port,
                   int exclass);
static void terminate_voice(struct snd_emux *emu, struct snd_emux_voice *vp, int free);
static void update_voice(struct snd_emux *emu, struct snd_emux_voice *vp, int update);
static void setup_voice(struct snd_emux_voice *vp);
static int calc_pan(struct snd_emux_voice *vp);
static int calc_volume(struct snd_emux_voice *vp);
static int calc_pitch(struct snd_emux_voice *vp);


/*
 * Start a note.
 */
void
snd_emux_note_on(void *p, int note, int vel, struct snd_midi_channel *chan)
{
    struct snd_emux *emu;
    int i, key, nvoices;
    struct snd_emux_voice *vp;
    struct snd_sf_zone *table[SNDRV_EMUX_MAX_MULTI_VOICES];
    unsigned long flags;
    struct snd_emux_port *port;

    port = p;
    if (snd_BUG_ON(!port || !chan))
        return;

    emu = port->emu;
    if (snd_BUG_ON(!emu || !emu->ops.get_voice || !emu->ops.trigger))
        return;

    key = note; /* remember the original note */
    nvoices = get_zone(emu, port, &note, vel, chan, table);
    if (! nvoices)
        return;

    /* exclusive note off */
    for (i = 0; i < nvoices; i++) {
        struct snd_sf_zone *zp = table[i];
        if (zp && zp->v.exclusiveClass)
            exclusive_note_off(emu, port, zp->v.exclusiveClass);
    }

#if 0 // seems not necessary
    /* Turn off the same note on the same channel. */
    terminate_note1(emu, key, chan, 0);
#endif

    spin_lock_irqsave(&emu->voice_lock, flags);
    for (i = 0; i < nvoices; i++) {

        /* set up each voice parameter */
        /* at this stage, we don't trigger the voice yet. */

        if (table[i] == NULL)
            continue;

        vp = emu->ops.get_voice(emu, port);
        if (vp == NULL || vp->ch < 0)
            continue;
        if (STATE_IS_PLAYING(vp->state))
            emu->ops.terminate(vp);

        vp->time = emu->use_time++;
        vp->chan = chan;
        vp->port = port;
        vp->key = key;
        vp->note = note;
        vp->velocity = vel;
        vp->zone = table[i];
        if (vp->zone->sample)
            vp->block = vp->zone->sample->block;
        else
            vp->block = NULL;

        setup_voice(vp);

        vp->state = SNDRV_EMUX_ST_STANDBY;
        if (emu->ops.prepare) {
            vp->state = SNDRV_EMUX_ST_OFF;
            if (emu->ops.prepare(vp) >= 0)
                vp->state = SNDRV_EMUX_ST_STANDBY;
        }
    }

    /* start envelope now */
    for (i = 0; i < emu->max_voices; i++) {
        vp = &emu->voices[i];
        if (vp->state == SNDRV_EMUX_ST_STANDBY &&
            vp->chan == chan) {
            emu->ops.trigger(vp);
            vp->state = SNDRV_EMUX_ST_ON;
            vp->ontime = jiffies; /* remember the trigger timing */
        }
    }
    spin_unlock_irqrestore(&emu->voice_lock, flags);

#ifdef SNDRV_EMUX_USE_RAW_EFFECT
    if (port->port_mode == SNDRV_EMUX_PORT_MODE_OSS_SYNTH) {
        /* clear voice position for the next note on this channel */
        struct snd_emux_effect_table *fx = chan->private;
        if (fx) {
            fx->flag[EMUX_FX_SAMPLE_START] = 0;
            fx->flag[EMUX_FX_COARSE_SAMPLE_START] = 0;
        }
    }
#endif
}

/*
 * Release a note in response to a midi note off.
 */
void
snd_emux_note_off(void *p, int note, int vel, struct snd_midi_channel *chan)
{
    int ch;
    struct snd_emux *emu;
    struct snd_emux_voice *vp;
    unsigned long flags;
    struct snd_emux_port *port;

    port = p;
    if (snd_BUG_ON(!port || !chan))
        return;

    emu = port->emu;
    if (snd_BUG_ON(!emu || !emu->ops.release))
        return;

    spin_lock_irqsave(&emu->voice_lock, flags);
    for (ch = 0; ch < emu->max_voices; ch++) {
        vp = &emu->voices[ch];
        if (STATE_IS_PLAYING(vp->state) &&
            vp->chan == chan && vp->key == note) {
            vp->state = SNDRV_EMUX_ST_RELEASED;
            if (vp->ontime == jiffies) {
                /* if note-off is sent too shortly after
                 * note-on, emuX engine cannot produce the sound
                 * correctly.  so we'll release this note
                 * a bit later via timer callback.
                 */
                vp->state = SNDRV_EMUX_ST_PENDING;
                if (! emu->timer_active) {
                    emu->tlist.expires = jiffies + 1;
                    add_timer(&emu->tlist);
                    emu->timer_active = 1;
                }
            } else
                /* ok now release the note */
                emu->ops.release(vp);
        }
    }
    spin_unlock_irqrestore(&emu->voice_lock, flags);
}

/*
 * timer callback
 *
 * release the pending note-offs
 */
void snd_emux_timer_callback(unsigned long data)
{
    struct snd_emux *emu = (struct snd_emux *) data;
    struct snd_emux_voice *vp;
    unsigned long flags;
    int ch, do_again = 0;

    spin_lock_irqsave(&emu->voice_lock, flags);
    for (ch = 0; ch < emu->max_voices; ch++) {
        vp = &emu->voices[ch];
        if (vp->state == SNDRV_EMUX_ST_PENDING) {
            if (vp->ontime == jiffies)
                do_again++; /* release this at the next interrupt */
            else {
                emu->ops.release(vp);
                vp->state = SNDRV_EMUX_ST_RELEASED;
            }
        }
    }
    if (do_again) {
        emu->tlist.expires = jiffies + 1;
        add_timer(&emu->tlist);
        emu->timer_active = 1;
    } else
        emu->timer_active = 0;
    spin_unlock_irqrestore(&emu->voice_lock, flags);
}

/*
 * key pressure change
 */
void
snd_emux_key_press(void *p, int note, int vel, struct snd_midi_channel *chan)
{
    int ch;
    struct snd_emux *emu;
    struct snd_emux_voice *vp;
    unsigned long flags;
    struct snd_emux_port *port;

    port = p;
    if (snd_BUG_ON(!port || !chan))
        return;

    emu = port->emu;
    if (snd_BUG_ON(!emu || !emu->ops.update))
        return;

    spin_lock_irqsave(&emu->voice_lock, flags);
    for (ch = 0; ch < emu->max_voices; ch++) {
        vp = &emu->voices[ch];
        if (vp->state == SNDRV_EMUX_ST_ON &&
            vp->chan == chan && vp->key == note) {
            vp->velocity = vel;
            update_voice(emu, vp, SNDRV_EMUX_UPDATE_VOLUME);
        }
    }
    spin_unlock_irqrestore(&emu->voice_lock, flags);
}


/*
 * Modulate the voices which belong to the channel
 */
void
snd_emux_update_channel(struct snd_emux_port *port, struct snd_midi_channel *chan, int update)
{
    struct snd_emux *emu;
    struct snd_emux_voice *vp;
    int i;
    unsigned long flags;

    if (! update)
        return;

    emu = port->emu;
    if (snd_BUG_ON(!emu || !emu->ops.update))
        return;

    spin_lock_irqsave(&emu->voice_lock, flags);
    for (i = 0; i < emu->max_voices; i++) {
        vp = &emu->voices[i];
        if (vp->chan == chan)
            update_voice(emu, vp, update);
    }
    spin_unlock_irqrestore(&emu->voice_lock, flags);
}

/*
 * Modulate all the voices which belong to the port.
 */
void
snd_emux_update_port(struct snd_emux_port *port, int update)
{
    struct snd_emux *emu; 
    struct snd_emux_voice *vp;
    int i;
    unsigned long flags;

    if (! update)
        return;

    emu = port->emu;
    if (snd_BUG_ON(!emu || !emu->ops.update))
        return;

    spin_lock_irqsave(&emu->voice_lock, flags);
    for (i = 0; i < emu->max_voices; i++) {
        vp = &emu->voices[i];
        if (vp->port == port)
            update_voice(emu, vp, update);
    }
    spin_unlock_irqrestore(&emu->voice_lock, flags);
}


/*
 * Deal with a controller type event.  This includes all types of
 * control events, not just the midi controllers
 */
void
snd_emux_control(void *p, int type, struct snd_midi_channel *chan)
{
    struct snd_emux_port *port;

    port = p;
    if (snd_BUG_ON(!port || !chan))
        return;

    switch (type) {
    case MIDI_CTL_MSB_MAIN_VOLUME:
    case MIDI_CTL_MSB_EXPRESSION:
        snd_emux_update_channel(port, chan, SNDRV_EMUX_UPDATE_VOLUME);
        break;
        
    case MIDI_CTL_MSB_PAN:
        snd_emux_update_channel(port, chan, SNDRV_EMUX_UPDATE_PAN);
        break;

    case MIDI_CTL_SOFT_PEDAL:
#ifdef SNDRV_EMUX_USE_RAW_EFFECT
        /* FIXME: this is an emulation */
        if (chan->control[type] >= 64)
            snd_emux_send_effect(port, chan, EMUX_FX_CUTOFF, -160,
                     EMUX_FX_FLAG_ADD);
        else
            snd_emux_send_effect(port, chan, EMUX_FX_CUTOFF, 0,
                     EMUX_FX_FLAG_OFF);
#endif
        break;

    case MIDI_CTL_PITCHBEND:
        snd_emux_update_channel(port, chan, SNDRV_EMUX_UPDATE_PITCH);
        break;

    case MIDI_CTL_MSB_MODWHEEL:
    case MIDI_CTL_CHAN_PRESSURE:
        snd_emux_update_channel(port, chan,
                    SNDRV_EMUX_UPDATE_FMMOD |
                    SNDRV_EMUX_UPDATE_FM2FRQ2);
        break;

    }

    if (port->chset.midi_mode == SNDRV_MIDI_MODE_XG) {
        snd_emux_xg_control(port, chan, type);
    }
}


/*
 * terminate note - if free flag is true, free the terminated voice
 */
static void
terminate_note1(struct snd_emux *emu, int note, struct snd_midi_channel *chan, int free)
{
    int  i;
    struct snd_emux_voice *vp;
    unsigned long flags;

    spin_lock_irqsave(&emu->voice_lock, flags);
    for (i = 0; i < emu->max_voices; i++) {
        vp = &emu->voices[i];
        if (STATE_IS_PLAYING(vp->state) && vp->chan == chan &&
            vp->key == note)
            terminate_voice(emu, vp, free);
    }
    spin_unlock_irqrestore(&emu->voice_lock, flags);
}


/*
 * terminate note - exported for midi emulation
 */
void
snd_emux_terminate_note(void *p, int note, struct snd_midi_channel *chan)
{
    struct snd_emux *emu;
    struct snd_emux_port *port;

    port = p;
    if (snd_BUG_ON(!port || !chan))
        return;

    emu = port->emu;
    if (snd_BUG_ON(!emu || !emu->ops.terminate))
        return;

    terminate_note1(emu, note, chan, 1);
}


/*
 * Terminate all the notes
 */
void
snd_emux_terminate_all(struct snd_emux *emu)
{
    int i;
    struct snd_emux_voice *vp;
    unsigned long flags;

    spin_lock_irqsave(&emu->voice_lock, flags);
    for (i = 0; i < emu->max_voices; i++) {
        vp = &emu->voices[i];
        if (STATE_IS_PLAYING(vp->state))
            terminate_voice(emu, vp, 0);
        if (vp->state == SNDRV_EMUX_ST_OFF) {
            if (emu->ops.free_voice)
                emu->ops.free_voice(vp);
            if (emu->ops.reset)
                emu->ops.reset(emu, i);
        }
        vp->time = 0;
    }
    /* initialize allocation time */
    emu->use_time = 0;
    spin_unlock_irqrestore(&emu->voice_lock, flags);
}

EXPORT_SYMBOL(snd_emux_terminate_all);

/*
 * Terminate all voices associated with the given port
 */
void
snd_emux_sounds_off_all(struct snd_emux_port *port)
{
    int i;
    struct snd_emux *emu;
    struct snd_emux_voice *vp;
    unsigned long flags;

    if (snd_BUG_ON(!port))
        return;
    emu = port->emu;
    if (snd_BUG_ON(!emu || !emu->ops.terminate))
        return;

    spin_lock_irqsave(&emu->voice_lock, flags);
    for (i = 0; i < emu->max_voices; i++) {
        vp = &emu->voices[i];
        if (STATE_IS_PLAYING(vp->state) &&
            vp->port == port)
            terminate_voice(emu, vp, 0);
        if (vp->state == SNDRV_EMUX_ST_OFF) {
            if (emu->ops.free_voice)
                emu->ops.free_voice(vp);
            if (emu->ops.reset)
                emu->ops.reset(emu, i);
        }
    }
    spin_unlock_irqrestore(&emu->voice_lock, flags);
}


/*
 * Terminate all voices that have the same exclusive class.  This
 * is mainly for drums.
 */
static void
exclusive_note_off(struct snd_emux *emu, struct snd_emux_port *port, int exclass)
{
    struct snd_emux_voice *vp;
    int  i;
    unsigned long flags;

    spin_lock_irqsave(&emu->voice_lock, flags);
    for (i = 0; i < emu->max_voices; i++) {
        vp = &emu->voices[i];
        if (STATE_IS_PLAYING(vp->state) && vp->port == port &&
            vp->reg.exclusiveClass == exclass) {
            terminate_voice(emu, vp, 0);
        }
    }
    spin_unlock_irqrestore(&emu->voice_lock, flags);
}

/*
 * terminate a voice
 * if free flag is true, call free_voice after termination
 */
static void
terminate_voice(struct snd_emux *emu, struct snd_emux_voice *vp, int free)
{
    emu->ops.terminate(vp);
    vp->time = emu->use_time++;
    vp->chan = NULL;
    vp->port = NULL;
    vp->zone = NULL;
    vp->block = NULL;
    vp->state = SNDRV_EMUX_ST_OFF;
    if (free && emu->ops.free_voice)
        emu->ops.free_voice(vp);
}


/*
 * Modulate the voice
 */
static void
update_voice(struct snd_emux *emu, struct snd_emux_voice *vp, int update)
{
    if (!STATE_IS_PLAYING(vp->state))
        return;

    if (vp->chan == NULL || vp->port == NULL)
        return;
    if (update & SNDRV_EMUX_UPDATE_VOLUME)
        calc_volume(vp);
    if (update & SNDRV_EMUX_UPDATE_PITCH)
        calc_pitch(vp);
    if (update & SNDRV_EMUX_UPDATE_PAN) {
        if (! calc_pan(vp) && (update == SNDRV_EMUX_UPDATE_PAN))
            return;
    }
    emu->ops.update(vp, update);
}


#if 0 // not used
/* table for volume target calculation */
static unsigned short voltarget[16] = { 
    0xEAC0, 0xE0C8, 0xD740, 0xCE20, 0xC560, 0xBD08, 0xB500, 0xAD58,
    0xA5F8, 0x9EF0, 0x9830, 0x91C0, 0x8B90, 0x85A8, 0x8000, 0x7A90
};
#endif

#define LO_BYTE(v)  ((v) & 0xff)
#define HI_BYTE(v)  (((v) >> 8) & 0xff)

/*
 * Sets up the voice structure by calculating some values that
 * will be needed later.
 */
static void
setup_voice(struct snd_emux_voice *vp)
{
    struct soundfont_voice_parm *parm;
    int pitch;

    /* copy the original register values */
    vp->reg = vp->zone->v;

#ifdef SNDRV_EMUX_USE_RAW_EFFECT
    snd_emux_setup_effect(vp);
#endif

    /* reset status */
    vp->apan = -1;
    vp->avol = -1;
    vp->apitch = -1;

    calc_volume(vp);
    calc_pitch(vp);
    calc_pan(vp);

    parm = &vp->reg.parm;

    /* compute filter target and correct modulation parameters */
    if (LO_BYTE(parm->modatkhld) >= 0x80 && parm->moddelay >= 0x8000) {
        parm->moddelay = 0xbfff;
        pitch = (HI_BYTE(parm->pefe) << 4) + vp->apitch;
        if (pitch > 0xffff)
            pitch = 0xffff;
        /* calculate filter target */
        vp->ftarget = parm->cutoff + LO_BYTE(parm->pefe);
        LIMITVALUE(vp->ftarget, 0, 255);
        vp->ftarget <<= 8;
    } else {
        vp->ftarget = parm->cutoff;
        vp->ftarget <<= 8;
        pitch = vp->apitch;
    }

    /* compute pitch target */
    if (pitch != 0xffff) {
        vp->ptarget = 1 << (pitch >> 12);
        if (pitch & 0x800) vp->ptarget += (vp->ptarget*0x102e)/0x2710;
        if (pitch & 0x400) vp->ptarget += (vp->ptarget*0x764)/0x2710;
        if (pitch & 0x200) vp->ptarget += (vp->ptarget*0x389)/0x2710;
        vp->ptarget += (vp->ptarget >> 1);
        if (vp->ptarget > 0xffff) vp->ptarget = 0xffff;
    } else
        vp->ptarget = 0xffff;

    if (LO_BYTE(parm->modatkhld) >= 0x80) {
        parm->modatkhld &= ~0xff;
        parm->modatkhld |= 0x7f;
    }

    /* compute volume target and correct volume parameters */
    vp->vtarget = 0;
#if 0 /* FIXME: this leads to some clicks.. */
    if (LO_BYTE(parm->volatkhld) >= 0x80 && parm->voldelay >= 0x8000) {
        parm->voldelay = 0xbfff;
        vp->vtarget = voltarget[vp->avol % 0x10] >> (vp->avol >> 4);
    }
#endif

    if (LO_BYTE(parm->volatkhld) >= 0x80) {
        parm->volatkhld &= ~0xff;
        parm->volatkhld |= 0x7f;
    }
}

/*
 * calculate pitch parameter
 */
static unsigned char pan_volumes[256] = {
0x00,0x03,0x06,0x09,0x0c,0x0f,0x12,0x14,0x17,0x1a,0x1d,0x20,0x22,0x25,0x28,0x2a,
0x2d,0x30,0x32,0x35,0x37,0x3a,0x3c,0x3f,0x41,0x44,0x46,0x49,0x4b,0x4d,0x50,0x52,
0x54,0x57,0x59,0x5b,0x5d,0x60,0x62,0x64,0x66,0x68,0x6a,0x6c,0x6f,0x71,0x73,0x75,
0x77,0x79,0x7b,0x7c,0x7e,0x80,0x82,0x84,0x86,0x88,0x89,0x8b,0x8d,0x8f,0x90,0x92,
0x94,0x96,0x97,0x99,0x9a,0x9c,0x9e,0x9f,0xa1,0xa2,0xa4,0xa5,0xa7,0xa8,0xaa,0xab,
0xad,0xae,0xaf,0xb1,0xb2,0xb3,0xb5,0xb6,0xb7,0xb9,0xba,0xbb,0xbc,0xbe,0xbf,0xc0,
0xc1,0xc2,0xc3,0xc5,0xc6,0xc7,0xc8,0xc9,0xca,0xcb,0xcc,0xcd,0xce,0xcf,0xd0,0xd1,
0xd2,0xd3,0xd4,0xd5,0xd6,0xd7,0xd7,0xd8,0xd9,0xda,0xdb,0xdc,0xdc,0xdd,0xde,0xdf,
0xdf,0xe0,0xe1,0xe2,0xe2,0xe3,0xe4,0xe4,0xe5,0xe6,0xe6,0xe7,0xe8,0xe8,0xe9,0xe9,
0xea,0xeb,0xeb,0xec,0xec,0xed,0xed,0xee,0xee,0xef,0xef,0xf0,0xf0,0xf1,0xf1,0xf1,
0xf2,0xf2,0xf3,0xf3,0xf3,0xf4,0xf4,0xf5,0xf5,0xf5,0xf6,0xf6,0xf6,0xf7,0xf7,0xf7,
0xf7,0xf8,0xf8,0xf8,0xf9,0xf9,0xf9,0xf9,0xf9,0xfa,0xfa,0xfa,0xfa,0xfb,0xfb,0xfb,
0xfb,0xfb,0xfc,0xfc,0xfc,0xfc,0xfc,0xfc,0xfc,0xfd,0xfd,0xfd,0xfd,0xfd,0xfd,0xfd,
0xfd,0xfe,0xfe,0xfe,0xfe,0xfe,0xfe,0xfe,0xfe,0xfe,0xfe,0xfe,0xfe,0xfe,0xfe,0xfe,
0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,
0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,
};

static int
calc_pan(struct snd_emux_voice *vp)
{
    struct snd_midi_channel *chan = vp->chan;
    int pan;

    /* pan & loop start (pan 8bit, MSB, 0:right, 0xff:left) */
    if (vp->reg.fixpan > 0) /* 0-127 */
        pan = 255 - (int)vp->reg.fixpan * 2;
    else {
        pan = chan->control[MIDI_CTL_MSB_PAN] - 64;
        if (vp->reg.pan >= 0) /* 0-127 */
            pan += vp->reg.pan - 64;
        pan = 127 - (int)pan * 2;
    }
    LIMITVALUE(pan, 0, 255);

    if (vp->emu->linear_panning) {
        /* assuming linear volume */
        if (pan != vp->apan) {
            vp->apan = pan;
            if (pan == 0)
                vp->aaux = 0xff;
            else
                vp->aaux = (-pan) & 0xff;
            return 1;
        } else
            return 0;
    } else {
        /* using volume table */
        if (vp->apan != (int)pan_volumes[pan]) {
            vp->apan = pan_volumes[pan];
            vp->aaux = pan_volumes[255 - pan];
            return 1;
        }
        return 0;
    }
}


/*
 * calculate volume attenuation
 *
 * Voice volume is controlled by volume attenuation parameter.
 * So volume becomes maximum when avol is 0 (no attenuation), and
 * minimum when 255 (-96dB or silence).
 */

/* tables for volume->attenuation calculation */
static unsigned char voltab1[128] = {
   0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63, 0x63,
   0x63, 0x2b, 0x29, 0x28, 0x27, 0x26, 0x25, 0x24, 0x23, 0x22,
   0x21, 0x20, 0x1f, 0x1e, 0x1e, 0x1d, 0x1c, 0x1b, 0x1b, 0x1a,
   0x19, 0x19, 0x18, 0x17, 0x17, 0x16, 0x16, 0x15, 0x15, 0x14,
   0x14, 0x13, 0x13, 0x13, 0x12, 0x12, 0x11, 0x11, 0x11, 0x10,
   0x10, 0x10, 0x0f, 0x0f, 0x0f, 0x0e, 0x0e, 0x0e, 0x0e, 0x0d,
   0x0d, 0x0d, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0b, 0x0b, 0x0b,
   0x0b, 0x0a, 0x0a, 0x0a, 0x0a, 0x09, 0x09, 0x09, 0x09, 0x09,
   0x08, 0x08, 0x08, 0x08, 0x08, 0x07, 0x07, 0x07, 0x07, 0x06,
   0x06, 0x06, 0x06, 0x06, 0x05, 0x05, 0x05, 0x05, 0x05, 0x04,
   0x04, 0x04, 0x04, 0x04, 0x03, 0x03, 0x03, 0x03, 0x03, 0x02,
   0x02, 0x02, 0x02, 0x02, 0x02, 0x01, 0x01, 0x01, 0x01, 0x01,
   0x01, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
};

static unsigned char voltab2[128] = {
   0x32, 0x31, 0x30, 0x2f, 0x2e, 0x2d, 0x2c, 0x2b, 0x2a, 0x2a,
   0x29, 0x28, 0x27, 0x26, 0x25, 0x24, 0x24, 0x23, 0x22, 0x21,
   0x21, 0x20, 0x1f, 0x1e, 0x1e, 0x1d, 0x1c, 0x1c, 0x1b, 0x1a,
   0x1a, 0x19, 0x19, 0x18, 0x18, 0x17, 0x16, 0x16, 0x15, 0x15,
   0x14, 0x14, 0x13, 0x13, 0x13, 0x12, 0x12, 0x11, 0x11, 0x10,
   0x10, 0x10, 0x0f, 0x0f, 0x0f, 0x0e, 0x0e, 0x0e, 0x0d, 0x0d,
   0x0d, 0x0c, 0x0c, 0x0c, 0x0b, 0x0b, 0x0b, 0x0b, 0x0a, 0x0a,
   0x0a, 0x0a, 0x09, 0x09, 0x09, 0x09, 0x09, 0x08, 0x08, 0x08,
   0x08, 0x08, 0x07, 0x07, 0x07, 0x07, 0x07, 0x06, 0x06, 0x06,
   0x06, 0x06, 0x06, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05,
   0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x03, 0x03, 0x03, 0x03,
   0x03, 0x03, 0x02, 0x02, 0x02, 0x02, 0x02, 0x02, 0x01, 0x01,
   0x01, 0x01, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00
};

static unsigned char expressiontab[128] = {
   0x7f, 0x6c, 0x62, 0x5a, 0x54, 0x50, 0x4b, 0x48, 0x45, 0x42,
   0x40, 0x3d, 0x3b, 0x39, 0x38, 0x36, 0x34, 0x33, 0x31, 0x30,
   0x2f, 0x2d, 0x2c, 0x2b, 0x2a, 0x29, 0x28, 0x27, 0x26, 0x25,
   0x24, 0x24, 0x23, 0x22, 0x21, 0x21, 0x20, 0x1f, 0x1e, 0x1e,
   0x1d, 0x1d, 0x1c, 0x1b, 0x1b, 0x1a, 0x1a, 0x19, 0x18, 0x18,
   0x17, 0x17, 0x16, 0x16, 0x15, 0x15, 0x15, 0x14, 0x14, 0x13,
   0x13, 0x12, 0x12, 0x11, 0x11, 0x11, 0x10, 0x10, 0x0f, 0x0f,
   0x0f, 0x0e, 0x0e, 0x0e, 0x0d, 0x0d, 0x0d, 0x0c, 0x0c, 0x0c,
   0x0b, 0x0b, 0x0b, 0x0a, 0x0a, 0x0a, 0x09, 0x09, 0x09, 0x09,
   0x08, 0x08, 0x08, 0x07, 0x07, 0x07, 0x07, 0x06, 0x06, 0x06,
   0x06, 0x05, 0x05, 0x05, 0x04, 0x04, 0x04, 0x04, 0x04, 0x03,
   0x03, 0x03, 0x03, 0x02, 0x02, 0x02, 0x02, 0x01, 0x01, 0x01,
   0x01, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
};

/*
 * Magic to calculate the volume (actually attenuation) from all the
 * voice and channels parameters.
 */
static int
calc_volume(struct snd_emux_voice *vp)
{
    int vol;
    int main_vol, expression_vol, master_vol;
    struct snd_midi_channel *chan = vp->chan;
    struct snd_emux_port *port = vp->port;

    expression_vol = chan->control[MIDI_CTL_MSB_EXPRESSION];
    LIMITMAX(vp->velocity, 127);
    LIMITVALUE(expression_vol, 0, 127);
    if (port->port_mode == SNDRV_EMUX_PORT_MODE_OSS_SYNTH) {
        /* 0 - 127 */
        main_vol = chan->control[MIDI_CTL_MSB_MAIN_VOLUME];
        vol = (vp->velocity * main_vol * expression_vol) / (127*127);
        vol = vol * vp->reg.amplitude / 127;

        LIMITVALUE(vol, 0, 127);

        /* calc to attenuation */
        vol = snd_sf_vol_table[vol];

    } else {
        main_vol = chan->control[MIDI_CTL_MSB_MAIN_VOLUME] * vp->reg.amplitude / 127;
        LIMITVALUE(main_vol, 0, 127);

        vol = voltab1[main_vol] + voltab2[vp->velocity];
        vol = (vol * 8) / 3;
        vol += vp->reg.attenuation;
        vol += ((0x100 - vol) * expressiontab[expression_vol])/128;
    }

    master_vol = port->chset.gs_master_volume;
    LIMITVALUE(master_vol, 0, 127);
    vol += snd_sf_vol_table[master_vol];
    vol += port->volume_atten;

#ifdef SNDRV_EMUX_USE_RAW_EFFECT
    if (chan->private) {
        struct snd_emux_effect_table *fx = chan->private;
        vol += fx->val[EMUX_FX_ATTEN];
    }
#endif

    LIMITVALUE(vol, 0, 255);
    if (vp->avol == vol)
        return 0; /* value unchanged */

    vp->avol = vol;
    if (!SF_IS_DRUM_BANK(get_bank(port, chan))
        && LO_BYTE(vp->reg.parm.volatkhld) < 0x7d) {
        int atten;
        if (vp->velocity < 70)
            atten = 70;
        else
            atten = vp->velocity;
        vp->acutoff = (atten * vp->reg.parm.cutoff + 0xa0) >> 7;
    } else {
        vp->acutoff = vp->reg.parm.cutoff;
    }

    return 1; /* value changed */
}

/*
 * calculate pitch offset
 *
 * 0xE000 is no pitch offset at 44100Hz sample.
 * Every 4096 is one octave.
 */

static int
calc_pitch(struct snd_emux_voice *vp)
{
    struct snd_midi_channel *chan = vp->chan;
    int offset;

    /* calculate offset */
    if (vp->reg.fixkey >= 0) {
        offset = (vp->reg.fixkey - vp->reg.root) * 4096 / 12;
    } else {
        offset = (vp->note - vp->reg.root) * 4096 / 12;
    }
    offset = (offset * vp->reg.scaleTuning) / 100;
    offset += vp->reg.tune * 4096 / 1200;
    if (chan->midi_pitchbend != 0) {
        /* (128 * 8192: 1 semitone) ==> (4096: 12 semitones) */
        offset += chan->midi_pitchbend * chan->gm_rpn_pitch_bend_range / 3072;
    }

    /* tuning via RPN:
     *   coarse = -8192 to 8192 (100 cent per 128)
     *   fine = -8192 to 8192 (max=100cent)
     */
    /* 4096 = 1200 cents in emu8000 parameter */
    offset += chan->gm_rpn_coarse_tuning * 4096 / (12 * 128);
    offset += chan->gm_rpn_fine_tuning / 24;

#ifdef SNDRV_EMUX_USE_RAW_EFFECT
    /* add initial pitch correction */
    if (chan->private) {
        struct snd_emux_effect_table *fx = chan->private;
        if (fx->flag[EMUX_FX_INIT_PITCH])
            offset += fx->val[EMUX_FX_INIT_PITCH];
    }
#endif

    /* 0xe000: root pitch */
    offset += 0xe000 + vp->reg.rate_offset;
    offset += vp->emu->pitch_shift;
    LIMITVALUE(offset, 0, 0xffff);
    if (offset == vp->apitch)
        return 0; /* unchanged */
    vp->apitch = offset;
    return 1; /* value changed */
}

/*
 * Get the bank number assigned to the channel
 */
static int
get_bank(struct snd_emux_port *port, struct snd_midi_channel *chan)
{
    int val;

    switch (port->chset.midi_mode) {
    case SNDRV_MIDI_MODE_XG:
        val = chan->control[MIDI_CTL_MSB_BANK];
        if (val == 127)
            return 128; /* return drum bank */
        return chan->control[MIDI_CTL_LSB_BANK];

    case SNDRV_MIDI_MODE_GS:
        if (chan->drum_channel)
            return 128;
        /* ignore LSB (bank map) */
        return chan->control[MIDI_CTL_MSB_BANK];
        
    default:
        if (chan->drum_channel)
            return 128;
        return chan->control[MIDI_CTL_MSB_BANK];
    }
}


/* Look for the zones matching with the given note and velocity.
 * The resultant zones are stored on table.
 */
static int
get_zone(struct snd_emux *emu, struct snd_emux_port *port,
     int *notep, int vel, struct snd_midi_channel *chan,
     struct snd_sf_zone **table)
{
    int preset, bank, def_preset, def_bank;

    bank = get_bank(port, chan);
    preset = chan->midi_program;

    if (SF_IS_DRUM_BANK(bank)) {
        def_preset = port->ctrls[EMUX_MD_DEF_DRUM];
        def_bank = bank;
    } else {
        def_preset = preset;
        def_bank = port->ctrls[EMUX_MD_DEF_BANK];
    }

    return snd_soundfont_search_zone(emu->sflist, notep, vel, preset, bank,
                     def_preset, def_bank,
                     table, SNDRV_EMUX_MAX_MULTI_VOICES);
}

/*
 */
void
snd_emux_init_voices(struct snd_emux *emu)
{
    struct snd_emux_voice *vp;
    int i;
    unsigned long flags;

    spin_lock_irqsave(&emu->voice_lock, flags);
    for (i = 0; i < emu->max_voices; i++) {
        vp = &emu->voices[i];
        vp->ch = -1; /* not used */
        vp->state = SNDRV_EMUX_ST_OFF;
        vp->chan = NULL;
        vp->port = NULL;
        vp->time = 0;
        vp->emu = emu;
        vp->hw = emu->hw;
    }
    spin_unlock_irqrestore(&emu->voice_lock, flags);
}

/*
 */
void snd_emux_lock_voice(struct snd_emux *emu, int voice)
{
    unsigned long flags;

    spin_lock_irqsave(&emu->voice_lock, flags);
    if (emu->voices[voice].state == SNDRV_EMUX_ST_OFF)
        emu->voices[voice].state = SNDRV_EMUX_ST_LOCKED;
    else
        snd_printk(KERN_WARNING
               "invalid voice for lock %d (state = %x)\n",
               voice, emu->voices[voice].state);
    spin_unlock_irqrestore(&emu->voice_lock, flags);
}

EXPORT_SYMBOL(snd_emux_lock_voice);

/*
 */
void snd_emux_unlock_voice(struct snd_emux *emu, int voice)
{
    unsigned long flags;

    spin_lock_irqsave(&emu->voice_lock, flags);
    if (emu->voices[voice].state == SNDRV_EMUX_ST_LOCKED)
        emu->voices[voice].state = SNDRV_EMUX_ST_OFF;
    else
        snd_printk(KERN_WARNING
               "invalid voice for unlock %d (state = %x)\n",
               voice, emu->voices[voice].state);
    spin_unlock_irqrestore(&emu->voice_lock, flags);
}

EXPORT_SYMBOL(snd_emux_unlock_voice);