path: root/sound/synth/emux/emux_synth.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  Midi synth routines for the Emu8k/Emu10k1
 *
 *  Copyright (C) 1999 Steve Ratcliffe
 *  Copyright (c) 1999-2000 Takashi Iwai <tiwai@suse.de>
 *
 *  Contains code based on awe_wave.c by Takashi Iwai
 */

#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 releas