seq_midi_emul.c

linux-2.6.15.6

/*
 *  GM/GS/XG midi module.
 *
 *  Copyright (C) 1999 Steve Ratcliffe
 *
 *  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
 *
 */
/*
 * This module is used to keep track of the current midi state.
 * It can be used for drivers that are required to emulate midi when
 * the hardware doesn't.
 *
 * It was written for a AWE64 driver, but there should be no AWE specific
 * code in here.  If there is it should be reported as a bug.
 */

#include <sound/driver.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <sound/core.h>
#include <sound/seq_kernel.h>
#include <sound/seq_midi_emul.h>
#include <sound/initval.h>
#include <sound/asoundef.h>

MODULE_AUTHOR("Takashi Iwai / Steve Ratcliffe");
MODULE_DESCRIPTION("Advanced Linux Sound Architecture sequencer MIDI emulation.");
MODULE_LICENSE("GPL");

/* Prototypes for static functions */
static void note_off(snd_midi_op_t *ops, void *drv, snd_midi_channel_t *chan, int note, int vel);
static void do_control(snd_midi_op_t *ops, void *private,
		       snd_midi_channel_set_t *chset, snd_midi_channel_t *chan,
		       int control, int value);
static void rpn(snd_midi_op_t *ops, void *drv, snd_midi_channel_t *chan, snd_midi_channel_set_t *chset);
static void nrpn(snd_midi_op_t *ops, void *drv, snd_midi_channel_t *chan, snd_midi_channel_set_t *chset);
static void sysex(snd_midi_op_t *ops, void *private, unsigned char *sysex, int len, snd_midi_channel_set_t *chset);
static void all_sounds_off(snd_midi_op_t *ops, void *private, snd_midi_channel_t *chan);
static void all_notes_off(snd_midi_op_t *ops, void *private, snd_midi_channel_t *chan);
static void snd_midi_reset_controllers(snd_midi_channel_t *chan);
static void reset_all_channels(snd_midi_channel_set_t *chset);


/*
 * Process an event in a driver independent way.  This means dealing
 * with RPN, NRPN, SysEx etc that are defined for common midi applications
 * such as GM, GS and XG.
 * There modes that this module will run in are:
 *   Generic MIDI - no interpretation at all, it will just save current values
 *                  of controlers etc.
 *   GM - You can use all gm_ prefixed elements of chan.  Controls, RPN, NRPN,
 *        SysEx will be interpreded as defined in General Midi.
 *   GS - You can use all gs_ prefixed elements of chan. Codes for GS will be
 *        interpreted.
 *   XG - You can use all xg_ prefixed elements of chan.  Codes for XG will
 *        be interpreted.
 */
void
snd_midi_process_event(snd_midi_op_t *ops,
		       snd_seq_event_t *ev, snd_midi_channel_set_t *chanset)
{
	snd_midi_channel_t *chan;
	void *drv;
	int dest_channel = 0;

	if (ev == NULL || chanset == NULL) {
		snd_printd("ev or chanbase NULL (snd_midi_process_event)\n");
		return;
	}
	if (chanset->channels == NULL)
		return;

	if (snd_seq_ev_is_channel_type(ev)) {
		dest_channel = ev->data.note.channel;
		if (dest_channel >= chanset->max_channels) {
			snd_printd("dest channel is %d, max is %d\n", dest_channel, chanset->max_channels);
			return;
		}
	}

	chan = chanset->channels + dest_channel;
	drv  = chanset->private_data;

	/* EVENT_NOTE should be processed before queued */
	if (ev->type == SNDRV_SEQ_EVENT_NOTE)
		return;

	/* Make sure that we don't have a note on that should really be
	 * a note off */
	if (ev->type == SNDRV_SEQ_EVENT_NOTEON && ev->data.note.velocity == 0)
		ev->type = SNDRV_SEQ_EVENT_NOTEOFF;

	/* Make sure the note is within array range */
	if (ev->type == SNDRV_SEQ_EVENT_NOTEON ||
	    ev->type == SNDRV_SEQ_EVENT_NOTEOFF ||
	    ev->type == SNDRV_SEQ_EVENT_KEYPRESS) {
		if (ev->data.note.note >= 128)
			return;
	}

	switch (ev->type) {
	case SNDRV_SEQ_EVENT_NOTEON:
		if (chan->note[ev->data.note.note] & SNDRV_MIDI_NOTE_ON) {
			if (ops->note_off)
				ops->note_off(drv, ev->data.note.note, 0, chan);
		}
		chan->note[ev->data.note.note] = SNDRV_MIDI_NOTE_ON;
		if (ops->note_on)
			ops->note_on(drv, ev->data.note.note, ev->data.note.velocity, chan);
		break;
	case SNDRV_SEQ_EVENT_NOTEOFF:
		if (! (chan->note[ev->data.note.note] & SNDRV_MIDI_NOTE_ON))
			break;
		if (ops->note_off)
			note_off(ops, drv, chan, ev->data.note.note, ev->data.note.velocity);
		break;
	case SNDRV_SEQ_EVENT_KEYPRESS:
		if (ops->key_press)
			ops->key_press(drv, ev->data.note.note, ev->data.note.velocity, chan);
		break;
	case SNDRV_SEQ_EVENT_CONTROLLER:
		do_control(ops, drv, chanset, chan,
			   ev->data.control.param, ev->data.control.value);
		break;
	case SNDRV_SEQ_EVENT_PGMCHANGE:
		chan->midi_program = ev->data.control.value;
		break;
	case SNDRV_SEQ_EVENT_PITCHBEND:
		chan->midi_pitchbend = ev->data.control.value;
		if (ops->control)
			ops->control(drv, MIDI_CTL_PITCHBEND, chan);
		break;
	case SNDRV_SEQ_EVENT_CHANPRESS:
		chan->midi_pressure = ev->data.control.value;
		if (ops->control)
			ops->control(drv, MIDI_CTL_CHAN_PRESSURE, chan);
		break;
	case SNDRV_SEQ_EVENT_CONTROL14:
		/* Best guess is that this is any of the 14 bit controller values */
		if (ev->data.control.param < 32) {
			/* set low part first */
			chan->control[ev->data.control.param + 32] =
				ev->data.control.value & 0x7f;
			do_control(ops, drv, chanset, chan,
				   ev->data.control.param,
				   ((ev->data.control.value>>7) & 0x7f));
		} else
			do_control(ops, drv, chanset, chan,
				   ev->data.control.param,
				   ev->data.control.value);
		break;
	case SNDRV_SEQ_EVENT_NONREGPARAM:
		/* Break it back into its controler values */
		chan->param_type = SNDRV_MIDI_PARAM_TYPE_NONREGISTERED;
		chan->control[MIDI_CTL_MSB_DATA_ENTRY]
			= (ev->data.control.value >> 7) & 0x7f;
		chan->control[MIDI_CTL_LSB_DATA_ENTRY]
			= ev->data.control.value & 0x7f;
		chan->control[MIDI_CTL_NONREG_PARM_NUM_MSB]
			= (ev->data.control.param >> 7) & 0x7f;
		chan->control[MIDI_CTL_NONREG_PARM_NUM_LSB]
			= ev->data.control.param & 0x7f;
		nrpn(ops, drv, chan, chanset);
		break;
	case SNDRV_SEQ_EVENT_REGPARAM:
		/* Break it back into its controler values */
		chan->param_type = SNDRV_MIDI_PARAM_TYPE_REGISTERED;
		chan->control[MIDI_CTL_MSB_DATA_ENTRY]
			= (ev->data.control.value >> 7) & 0x7f;
		chan->control[MIDI_CTL_LSB_DATA_ENTRY]
			= ev->data.control.value & 0x7f;
		chan->control[MIDI_CTL_REGIST_PARM_NUM_MSB]
			= (ev->data.control.param >> 7) & 0x7f;
		chan->control[MIDI_CTL_REGIST_PARM_NUM_LSB]
			= ev->data.control.param & 0x7f;
		rpn(ops, drv, chan, chanset);
		break;
	case SNDRV_SEQ_EVENT_SYSEX:
		if ((ev->flags & SNDRV_SEQ_EVENT_LENGTH_MASK) == SNDRV_SEQ_EVENT_LENGTH_VARIABLE) {
			unsigned char sysexbuf[64];
			int len;
			len = snd_seq_expand_var_event(ev, sizeof(sysexbuf), sysexbuf, 1, 0);
			if (len > 0)
				sysex(ops, drv, sysexbuf, len, chanset);
		}
		break;
	case SNDRV_SEQ_EVENT_SONGPOS:
	case SNDRV_SEQ_EVENT_SONGSEL:
	case SNDRV_SEQ_EVENT_CLOCK:
	case SNDRV_SEQ_EVENT_START:
	case SNDRV_SEQ_EVENT_CONTINUE:
	case SNDRV_SEQ_EVENT_STOP:
	case SNDRV_SEQ_EVENT_QFRAME:
	case SNDRV_SEQ_EVENT_TEMPO:
	case SNDRV_SEQ_EVENT_TIMESIGN:
	case SNDRV_SEQ_EVENT_KEYSIGN:
		goto not_yet;
	case SNDRV_SEQ_EVENT_SENSING:
		break;
	case SNDRV_SEQ_EVENT_CLIENT_START:
	case SNDRV_SEQ_EVENT_CLIENT_EXIT:
	case SNDRV_SEQ_EVENT_CLIENT_CHANGE:
	case SNDRV_SEQ_EVENT_PORT_START:
	case SNDRV_SEQ_EVENT_PORT_EXIT:
	case SNDRV_SEQ_EVENT_PORT_CHANGE:
	case SNDRV_SEQ_EVENT_SAMPLE:
	case SNDRV_SEQ_EVENT_SAMPLE_START:
	case SNDRV_SEQ_EVENT_SAMPLE_STOP:
	case SNDRV_SEQ_EVENT_SAMPLE_FREQ:
	case SNDRV_SEQ_EVENT_SAMPLE_VOLUME:
	case SNDRV_SEQ_EVENT_SAMPLE_LOOP:
	case SNDRV_SEQ_EVENT_SAMPLE_POSITION:
	case SNDRV_SEQ_EVENT_ECHO:
	not_yet:
	default:
		/*snd_printd("Unimplemented event %d\n", ev->type);*/
		break;
	}
}


/*
 * release note
 */
static void
note_off(snd_midi_op_t *ops, void *drv, snd_midi_channel_t *chan, int note, int vel)
{
	if (chan->gm_hold) {
		/* Hold this note until pedal is turned off */
		chan->note[note] |= SNDRV_MIDI_NOTE_RELEASED;
	} else if (chan->note[note] & SNDRV_MIDI_NOTE_SOSTENUTO) {
		/* Mark this note as release; it will be turned off when sostenuto
		 * is turned off */
		chan->note[note] |= SNDRV_MIDI_NOTE_RELEASED;
	} else {
		chan->note[note] = 0;
		if (ops->note_off)
			ops->note_off(drv, note, vel, chan);
	}
}

/*
 * Do all driver independent operations for this controler and pass
 * events that need to take place immediately to the driver.
 */
static void
do_control(snd_midi_op_t *ops, void *drv, snd_midi_channel_set_t *chset,
	   snd_midi_channel_t *chan, int control, int value)
{
	int  i;

	/* Switches */
	if ((control >=64 && control <=69) || (control >= 80 && control <= 83)) {
		/* These are all switches; either off or on so set to 0 or 127 */
		value = (value >= 64)? 127: 0;
	}
	chan->control[control] = value;

	switch (control) {
	case MIDI_CTL_SUSTAIN:
		if (value == 0) {
			/* Sustain has been released, turn off held notes */
			for (i = 0; i < 128; i++) {
				if (chan->note[i] & SNDRV_MIDI_NOTE_RELEASED) {
					chan->note[i] = SNDRV_MIDI_NOTE_OFF;
					if (ops->note_off)
						ops->note_off(drv, i, 0, chan);
				}
			}
		}
		break;
	case MIDI_CTL_PORTAMENTO:
		break;
	case MIDI_CTL_SOSTENUTO:
		if (value) {
			/* Mark each note that is currently held down */
			for (i = 0; i < 128; i++) {
				if (chan->note[i] & SNDRV_MIDI_NOTE_ON)
					chan->note[i] |= SNDRV_MIDI_NOTE_SOSTENUTO;
			}
		} else {
			/* release all notes that were held */
			for (i = 0; i < 128; i++) {
				if (chan->note[i] & SNDRV_MIDI_NOTE_SOSTENUTO) {
					chan->note[i] &= ~SNDRV_MIDI_NOTE_SOSTENUTO;
					if (chan->note[i] & SNDRV_MIDI_NOTE_RELEASED) {
						chan->note[i] = SNDRV_MIDI_NOTE_OFF;
						if (ops->note_off)
							ops->note_off(drv, i, 0, chan);
					}
				}
			}
		}
		break;
	case MIDI_CTL_MSB_DATA_ENTRY:
		chan->control[MIDI_CTL_LSB_DATA_ENTRY] = 0;
		/* go through here */
	case MIDI_CTL_LSB_DATA_ENTRY:
		if (chan->param_type == SNDRV_MIDI_PARAM_TYPE_REGISTERED)
			rpn(ops, drv, chan, chset);
		else
			nrpn(ops, drv, chan, chset);
		break;
	case MIDI_CTL_REGIST_PARM_NUM_LSB:
	case MIDI_CTL_REGIST_PARM_NUM_MSB:
		chan->param_type = SNDRV_MIDI_PARAM_TYPE_REGISTERED;
		break;
	case MIDI_CTL_NONREG_PARM_NUM_LSB:
	case MIDI_CTL_NONREG_PARM_NUM_MSB:
		chan->param_type = SNDRV_MIDI_PARAM_TYPE_NONREGISTERED;
		break;

	case MIDI_CTL_ALL_SOUNDS_OFF:
		all_sounds_off(ops, drv, chan);
		break;

	case MIDI_CTL_ALL_NOTES_OFF:
		all_notes_off(ops, drv, chan);
		break;

	case MIDI_CTL_MSB_BANK:
		if (chset->midi_mode == SNDRV_MIDI_MODE_XG) {
			if (value == 127)
				chan->drum_channel = 1;
			else
				chan->drum_channel = 0;
		}
		break;
	case MIDI_CTL_LSB_BANK:
		break;

	case MIDI_CTL_RESET_CONTROLLERS:
		snd_midi_reset_controllers(chan);
		break;

	case MIDI_CTL_SOFT_PEDAL:
	case MIDI_CTL_LEGATO_FOOTSWITCH:
	case MIDI_CTL_HOLD2:
	case MIDI_CTL_SC1_SOUND_VARIATION:
	case MIDI_CTL_SC2_TIMBRE:
	case MIDI_CTL_SC3_RELEASE_TIME:
	case MIDI_CTL_SC4_ATTACK_TIME:
	case MIDI_CTL_SC5_BRIGHTNESS:
	case MIDI_CTL_E1_REVERB_DEPTH:
	case MIDI_CTL_E2_TREMOLO_DEPTH:
	case MIDI_CTL_E3_CHORUS_DEPTH:
	case MIDI_CTL_E4_DETUNE_DEPTH:
	case MIDI_CTL_E5_PHASER_DEPTH:
		goto notyet;
	notyet:
	default:
		if (ops->control)