[deliverable/linux.git] / sound / core / seq / seq_midi_event.c

/*
 *  MIDI byte <-> sequencer event coder
 *
 *  Copyright (C) 1998,99 Takashi Iwai <tiwai@suse.de>,
 *                        Jaroslav Kysela <perex@suse.cz>
 *
 *   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 <sound/driver.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <sound/core.h>
#include <sound/seq_kernel.h>
#include <sound/seq_midi_event.h>
#include <sound/asoundef.h>

MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>, Jaroslav Kysela <perex@suse.cz>");
MODULE_DESCRIPTION("MIDI byte <-> sequencer event coder");
MODULE_LICENSE("GPL");

/* queue type */
/* from 0 to 7 are normal commands (note off, on, etc.) */
#define ST_NOTEOFF	0
#define ST_NOTEON	1
#define ST_SPECIAL	8
#define ST_SYSEX	ST_SPECIAL
/* from 8 to 15 are events for 0xf0-0xf7 */


/* status event types */
typedef void (*event_encode_t)(snd_midi_event_t *dev, snd_seq_event_t *ev);
typedef void (*event_decode_t)(snd_seq_event_t *ev, unsigned char *buf);

/*
 * prototypes
 */
static void note_event(snd_midi_event_t *dev, snd_seq_event_t *ev);
static void one_param_ctrl_event(snd_midi_event_t *dev, snd_seq_event_t *ev);
static void pitchbend_ctrl_event(snd_midi_event_t *dev, snd_seq_event_t *ev);
static void two_param_ctrl_event(snd_midi_event_t *dev, snd_seq_event_t *ev);
static void one_param_event(snd_midi_event_t *dev, snd_seq_event_t *ev);
static void songpos_event(snd_midi_event_t *dev, snd_seq_event_t *ev);
static void note_decode(snd_seq_event_t *ev, unsigned char *buf);
static void one_param_decode(snd_seq_event_t *ev, unsigned char *buf);
static void pitchbend_decode(snd_seq_event_t *ev, unsigned char *buf);
static void two_param_decode(snd_seq_event_t *ev, unsigned char *buf);
static void songpos_decode(snd_seq_event_t *ev, unsigned char *buf);

/*
 * event list
 */
static struct status_event_list_t {
	int event;
	int qlen;
	event_encode_t encode;
	event_decode_t decode;
} status_event[] = {
	/* 0x80 - 0xf0 */
	{SNDRV_SEQ_EVENT_NOTEOFF,	2, note_event, note_decode},
	{SNDRV_SEQ_EVENT_NOTEON,	2, note_event, note_decode},
	{SNDRV_SEQ_EVENT_KEYPRESS,	2, note_event, note_decode},
	{SNDRV_SEQ_EVENT_CONTROLLER,	2, two_param_ctrl_event, two_param_decode},
	{SNDRV_SEQ_EVENT_PGMCHANGE,	1, one_param_ctrl_event, one_param_decode},
	{SNDRV_SEQ_EVENT_CHANPRESS,	1, one_param_ctrl_event, one_param_decode},
	{SNDRV_SEQ_EVENT_PITCHBEND,	2, pitchbend_ctrl_event, pitchbend_decode},
	{SNDRV_SEQ_EVENT_NONE,		0, NULL, NULL}, /* 0xf0 */
	/* 0xf0 - 0xff */
	{SNDRV_SEQ_EVENT_SYSEX,		1, NULL, NULL}, /* sysex: 0xf0 */
	{SNDRV_SEQ_EVENT_QFRAME,	1, one_param_event, one_param_decode}, /* 0xf1 */
	{SNDRV_SEQ_EVENT_SONGPOS,	2, songpos_event, songpos_decode}, /* 0xf2 */
	{SNDRV_SEQ_EVENT_SONGSEL,	1, one_param_event, one_param_decode}, /* 0xf3 */
	{SNDRV_SEQ_EVENT_NONE,		0, NULL, NULL}, /* 0xf4 */
	{SNDRV_SEQ_EVENT_NONE,		0, NULL, NULL}, /* 0xf5 */
	{SNDRV_SEQ_EVENT_TUNE_REQUEST,	0, NULL, NULL},	/* 0xf6 */
	{SNDRV_SEQ_EVENT_NONE,		0, NULL, NULL}, /* 0xf7 */
	{SNDRV_SEQ_EVENT_CLOCK,		0, NULL, NULL}, /* 0xf8 */
	{SNDRV_SEQ_EVENT_NONE,		0, NULL, NULL}, /* 0xf9 */
	{SNDRV_SEQ_EVENT_START,		0, NULL, NULL}, /* 0xfa */
	{SNDRV_SEQ_EVENT_CONTINUE,	0, NULL, NULL}, /* 0xfb */
	{SNDRV_SEQ_EVENT_STOP, 		0, NULL, NULL}, /* 0xfc */
	{SNDRV_SEQ_EVENT_NONE, 		0, NULL, NULL}, /* 0xfd */
	{SNDRV_SEQ_EVENT_SENSING, 	0, NULL, NULL}, /* 0xfe */
	{SNDRV_SEQ_EVENT_RESET, 	0, NULL, NULL}, /* 0xff */
};

static int extra_decode_ctrl14(snd_midi_event_t *dev, unsigned char *buf, int len, snd_seq_event_t *ev);
static int extra_decode_xrpn(snd_midi_event_t *dev, unsigned char *buf, int count, snd_seq_event_t *ev);

static struct extra_event_list_t {
	int event;
	int (*decode)(snd_midi_event_t *dev, unsigned char *buf, int len, snd_seq_event_t *ev);
} extra_event[] = {
	{SNDRV_SEQ_EVENT_CONTROL14, extra_decode_ctrl14},
	{SNDRV_SEQ_EVENT_NONREGPARAM, extra_decode_xrpn},
	{SNDRV_SEQ_EVENT_REGPARAM, extra_decode_xrpn},
};

/*
 *  new/delete record
 */

int snd_midi_event_new(int bufsize, snd_midi_event_t **rdev)
{
	snd_midi_event_t *dev;

	*rdev = NULL;
	dev = kcalloc(1, sizeof(*dev), GFP_KERNEL);
	if (dev == NULL)
		return -ENOMEM;
	if (bufsize > 0) {
		dev->buf = kmalloc(bufsize, GFP_KERNEL);
		if (dev->buf == NULL) {
			kfree(dev);
			return -ENOMEM;
		}
	}
	dev->bufsize = bufsize;
	dev->lastcmd = 0xff;
	spin_lock_init(&dev->lock);
	*rdev = dev;
	return 0;
}

void snd_midi_event_free(snd_midi_event_t *dev)
{
	if (dev != NULL) {
		kfree(dev->buf);
		kfree(dev);
	}
}

/*
 * initialize record
 */
inline static void reset_encode(snd_midi_event_t *dev)
{
	dev->read = 0;
	dev->qlen = 0;
	dev->type = 0;
}

void snd_midi_event_reset_encode(snd_midi_event_t *dev)
{
	unsigned long flags;

	spin_lock_irqsave(&dev->lock, flags);
	reset_encode(dev);
	spin_unlock_irqrestore(&dev->lock, flags);
}

void snd_midi_event_reset_decode(snd_midi_event_t *dev)
{
	unsigned long flags;

	spin_lock_irqsave(&dev->lock, flags);
	dev->lastcmd = 0xff;
	spin_unlock_irqrestore(&dev->lock, flags);
}

void snd_midi_event_init(snd_midi_event_t *dev)
{
	snd_midi_event_reset_encode(dev);
	snd_midi_event_reset_decode(dev);
}

void snd_midi_event_no_status(snd_midi_event_t *dev, int on)
{
	dev->nostat = on ? 1 : 0;
}

/*
 * resize buffer
 */
int snd_midi_event_resize_buffer(snd_midi_event_t *dev, int bufsize)
{
	unsigned char *new_buf, *old_buf;
	unsigned long flags;

	if (bufsize == dev->bufsize)
		return 0;
	new_buf = kmalloc(bufsize, GFP_KERNEL);
	if (new_buf == NULL)
		return -ENOMEM;
	spin_lock_irqsave(&dev->lock, flags);
	old_buf = dev->buf;
	dev->buf = new_buf;
	dev->bufsize = bufsize;
	reset_encode(dev);
	spin_unlock_irqrestore(&dev->lock, flags);
	kfree(old_buf);
	return 0;
}

/*
 *  read bytes and encode to sequencer event if finished
 *  return the size of encoded bytes
 */
long snd_midi_event_encode(snd_midi_event_t *dev, unsigned char *buf, long count, snd_seq_event_t *ev)
{
	long result = 0;
	int rc;

	ev->type = SNDRV_SEQ_EVENT_NONE;

	while (count-- > 0) {
		rc = snd_midi_event_encode_byte(dev, *buf++, ev);
		result++;
		if (rc < 0)
			return rc;
		else if (rc > 0)
			return result;
	}

	return result;
}

/*
 *  read one byte and encode to sequencer event:
 *  return 1 if MIDI bytes are encoded to an event
 *         0 data is not finished
 *         negative for error
 */
int snd_midi_event_encode_byte(snd_midi_event_t *dev, int c, snd_seq_event_t *ev)
{
	int rc = 0;
	unsigned long flags;

	c &= 0xff;

	if (c >= MIDI_CMD_COMMON_CLOCK) {
		/* real-time event */
		ev->type = status_event[ST_SPECIAL + c - 0xf0].event;
		ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK;
		ev->flags |= SNDRV_SEQ_EVENT_LENGTH_FIXED;
		return 1;
	}

	spin_lock_irqsave(&dev->lock, flags);
	if (dev->qlen > 0) {
		/* rest of command */
		dev->buf[dev->read++] = c;
		if (dev->type != ST_SYSEX)
			dev->qlen--;
	} else {
		/* new command */
		dev->read = 1;
		if (c & 0x80) {
			dev->buf[0] = c;
			if ((c & 0xf0) == 0xf0) /* special events */
				dev->type = (c & 0x0f) + ST_SPECIAL;
			else
				dev->type = (c >> 4) & 0x07;
			dev->qlen = status_event[dev->type].qlen;
		} else {
			/* process this byte as argument */
			dev->buf[dev->read++] = c;
			dev->qlen = status_event[dev->type].qlen - 1;
		}
	}
	if (dev->qlen == 0) {
		ev->type = status_event[dev->type].event;
		ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK;
		ev->flags |= SNDRV_SEQ_EVENT_LENGTH_FIXED;
		if (status_event[dev->type].encode) /* set data values */
			status_event[dev->type].encode(dev, ev);
		rc = 1;
	} else 	if (dev->type == ST_SYSEX) {
		if (c == MIDI_CMD_COMMON_SYSEX_END ||
		    dev->read >= dev->bufsize) {
			ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK;
			ev->flags |= SNDRV_SEQ_EVENT_LENGTH_VARIABLE;
			ev->type = SNDRV_SEQ_EVENT_SYSEX;
			ev->data.ext.len = dev->read;
			ev->data.ext.ptr = dev->buf;
			if (c != MIDI_CMD_COMMON_SYSEX_END)
				dev->read = 0; /* continue to parse */
			else
				reset_encode(dev); /* all parsed */
			rc = 1;
		}
	}

	spin_unlock_irqrestore(&dev->lock, flags);
	return rc;
}

/* encode note event */
static void note_event(snd_midi_event_t *dev, snd_seq_event_t *ev)
{
	ev->data.note.channel = dev->buf[0] & 0x0f;
	ev->data.note.note = dev->buf[1];
	ev->data.note.velocity = dev->buf[2];
}

/* encode one parameter controls */
static void one_param_ctrl_event(snd_midi_event_t *dev, snd_seq_event_t *ev)
{
	ev->data.control.channel = dev->buf[0] & 0x0f;
	ev->data.control.value = dev->buf[1];
}

/* encode pitch wheel change */
static void pitchbend_ctrl_event(snd_midi_event_t *dev, snd_seq_event_t *ev)
{
	ev->data.control.channel = dev->buf[0] & 0x0f;
	ev->data.control.value = (int)dev->buf[2] * 128 + (int)dev->buf[1] - 8192;
}

/* encode midi control change */
static void two_param_ctrl_event(snd_midi_event_t *dev, snd_seq_event_t *ev)
{
	ev->data.control.channel = dev->buf[0] & 0x0f;
	ev->data.control.param = dev->buf[1];
	ev->data.control.value = dev->buf[2];
}

/* encode one parameter value*/
static void one_param_event(snd_midi_event_t *dev, snd_seq_event_t *ev)
{
	ev->data.control.value = dev->buf[1];
}

/* encode song position */
static void songpos_event(snd_midi_event_t *dev, snd_seq_event_t *ev)
{
	ev->data.control.value = (int)dev->buf[2] * 128 + (int)dev->buf[1];
}

/*
 * decode from a sequencer event to midi bytes
 * return the size of decoded midi events
 */
long snd_midi_event_decode(snd_midi_event_t *dev, unsigned char *buf, long count, snd_seq_event_t *ev)
{
	unsigned int cmd, type;

	if (ev->type == SNDRV_SEQ_EVENT_NONE)
		return -ENOENT;

	for (type = 0; type < ARRAY_SIZE(status_event); type++) {
		if (ev->type == status_event[type].event)
			goto __found;
	}
	for (type = 0; type < ARRAY_SIZE(extra_event); type++) {
		if (ev->type == extra_event[type].event)
			return extra_event[type].decode(dev, buf, count, ev);
	}
	return -ENOENT;

      __found:
	if (type >= ST_SPECIAL)
		cmd = 0xf0 + (type - ST_SPECIAL);
	else
		/* data.note.channel and data.control.channel is identical */
		cmd = 0x80 | (type << 4) | (ev->data.note.channel & 0x0f);


	if (cmd == MIDI_CMD_COMMON_SYSEX) {
		snd_midi_event_reset_decode(dev);
		return snd_seq_expand_var_event(ev, count, buf, 1, 0);
	} else {
		int qlen;
		unsigned char xbuf[4];
		unsigned long flags;

		spin_lock_irqsave(&dev->lock, flags);
		if ((cmd & 0xf0) == 0xf0 || dev->lastcmd != cmd || dev->nostat) {
			dev->lastcmd = cmd;
			spin_unlock_irqrestore(&dev->lock, flags);
			xbuf[0] = cmd;
			if (status_event[type].decode)
				status_event[type].decode(ev, xbuf + 1);
			qlen = status_event[type].qlen + 1;
		} else {
			spin_unlock_irqrestore(&dev->lock, flags);
			if (status_event[type].decode)
				status_event[type].decode(ev, xbuf + 0);
			qlen = status_event[type].qlen;
		}
		if (count < qlen)
			return -ENOMEM;
		memcpy(buf, xbuf, qlen);
		return qlen;
	}
}


/* decode note event */
static void note_decode(snd_seq_event_t *ev, unsigned char *buf)
{
	buf[0] = ev->data.note.note & 0x7f;
	buf[1] = ev->data.note.velocity & 0x7f;
}

/* decode one parameter controls */
static void one_param_decode(snd_seq_event_t *ev, unsigned char *buf)
{
	buf[0] = ev->data.control.value & 0x7f;
}

/* decode pitch wheel change */
static void pitchbend_decode(snd_seq_event_t *ev, unsigned char *buf)
{
	int value = ev->data.control.value + 8192;
	buf[0] = value & 0x7f;
	buf[1] = (value >> 7) & 0x7f;
}

/* decode midi control change */
static void two_param_decode(snd_seq_event_t *ev, unsigned char *buf)
{
	buf[0] = ev->data.control.param & 0x7f;
	buf[1] = ev->data.control.value & 0x7f;
}

/* decode song position */
static void songpos_decode(snd_seq_event_t *ev, unsigned char *buf)
{
	buf[0] = ev->data.control.value & 0x7f;
	buf[1] = (ev->data.control.value >> 7) & 0x7f;
}

/* decode 14bit control */
static int extra_decode_ctrl14(snd_midi_event_t *dev, unsigned char *buf, int count, snd_seq_event_t *ev)
{
	unsigned char cmd;
	int idx = 0;

	cmd = MIDI_CMD_CONTROL|(ev->data.control.channel & 0x0f);
	if (ev->data.control.param < 0x20) {
		if (count < 4)
			return -ENOMEM;
		if (dev->nostat && count < 6)
			return -ENOMEM;
		if (cmd != dev->lastcmd || dev->nostat) {
			if (count < 5)
				return -ENOMEM;
			buf[idx++] = dev->lastcmd = cmd;
		}
		buf[idx++] = ev->data.control.param;
		buf[idx++] = (ev->data.control.value >> 7) & 0x7f;
		if (dev->nostat)
			buf[idx++] = cmd;
		buf[idx++] = ev->data.control.param + 0x20;
		buf[idx++] = ev->data.control.value & 0x7f;
	} else {
		if (count < 2)
			return -ENOMEM;
		if (cmd != dev->lastcmd || dev->nostat) {
			if (count < 3)
				return -ENOMEM;
			buf[idx++] = dev->lastcmd = cmd;
		}
		buf[idx++] = ev->data.control.param & 0x7f;
		buf[idx++] = ev->data.control.value & 0x7f;
	}
	return idx;
}

/* decode reg/nonreg param */
static int extra_decode_xrpn(snd_midi_event_t *dev, unsigned char *buf, int count, snd_seq_event_t *ev)
{
	unsigned char cmd;
	char *cbytes;
	static char cbytes_nrpn[4] = { MIDI_CTL_NONREG_PARM_NUM_MSB,
				       MIDI_CTL_NONREG_PARM_NUM_LSB,
				       MIDI_CTL_MSB_DATA_ENTRY,
				       MIDI_CTL_LSB_DATA_ENTRY };
	static char cbytes_rpn[4] =  { MIDI_CTL_REGIST_PARM_NUM_MSB,
				       MIDI_CTL_REGIST_PARM_NUM_LSB,
				       MIDI_CTL_MSB_DATA_ENTRY,
				       MIDI_CTL_LSB_DATA_ENTRY };
	unsigned char bytes[4];
	int idx = 0, i;

	if (count < 8)
		return -ENOMEM;
	if (dev->nostat && count < 12)
		return -ENOMEM;
	cmd = MIDI_CMD_CONTROL|(ev->data.control.channel & 0x0f);
	bytes[0] = ev->data.control.param & 0x007f;
	bytes[1] = (ev->data.control.param & 0x3f80) >> 7;
	bytes[2] = ev->data.control.value & 0x007f;
	bytes[3] = (ev->data.control.value & 0x3f80) >> 7;
	if (cmd != dev->lastcmd && !dev->nostat) {
		if (count < 9)
			return -ENOMEM;
		buf[idx++] = dev->lastcmd = cmd;
	}
	cbytes = ev->type == SNDRV_SEQ_EVENT_NONREGPARAM ? cbytes_nrpn : cbytes_rpn;
	for (i = 0; i < 4; i++) {
		if (dev->nostat)
			buf[idx++] = dev->lastcmd = cmd;
		buf[idx++] = cbytes[i];
		buf[idx++] = bytes[i];
	}
	return idx;
}

/*
 *  exports
 */
 
EXPORT_SYMBOL(snd_midi_event_new);
EXPORT_SYMBOL(snd_midi_event_free);
EXPORT_SYMBOL(snd_midi_event_resize_buffer);
EXPORT_SYMBOL(snd_midi_event_init);
EXPORT_SYMBOL(snd_midi_event_reset_encode);
EXPORT_SYMBOL(snd_midi_event_reset_decode);
EXPORT_SYMBOL(snd_midi_event_no_status);
EXPORT_SYMBOL(snd_midi_event_encode);
EXPORT_SYMBOL(snd_midi_event_encode_byte);
EXPORT_SYMBOL(snd_midi_event_decode);

static int __init alsa_seq_midi_event_init(void)
{
	return 0;
}

static void __exit alsa_seq_midi_event_exit(void)
{
}

module_init(alsa_seq_midi_event_init)
module_exit(alsa_seq_midi_event_exit)
Commit	Line	Data
1da177e4 LT	1	/*
	2	* MIDI byte <-> sequencer event coder
	3	*
	4	* Copyright (C) 1998,99 Takashi Iwai <tiwai@suse.de>,
	5	* Jaroslav Kysela <perex@suse.cz>
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License as published by
	9	* the Free Software Foundation; either version 2 of the License, or
	10	* (at your option) any later version.
	11	*
	12	* This program is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	* GNU General Public License for more details.
	16	*
	17	* You should have received a copy of the GNU General Public License
	18	* along with this program; if not, write to the Free Software
	19	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	20	*/
	21
	22	#include <sound/driver.h>
	23	#include <linux/slab.h>
	24	#include <linux/errno.h>
	25	#include <linux/string.h>
	26	#include <sound/core.h>
	27	#include <sound/seq_kernel.h>
	28	#include <sound/seq_midi_event.h>
	29	#include <sound/asoundef.h>
	30
	31	MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>, Jaroslav Kysela <perex@suse.cz>");
	32	MODULE_DESCRIPTION("MIDI byte <-> sequencer event coder");
	33	MODULE_LICENSE("GPL");
	34
	35	/* queue type */
	36	/* from 0 to 7 are normal commands (note off, on, etc.) */
	37	#define ST_NOTEOFF 0
	38	#define ST_NOTEON 1
	39	#define ST_SPECIAL 8
	40	#define ST_SYSEX ST_SPECIAL
	41	/* from 8 to 15 are events for 0xf0-0xf7 */
	42
	43
	44	/* status event types */
	45	typedef void (event_encode_t)(snd_midi_event_t dev, snd_seq_event_t *ev);
	46	typedef void (event_decode_t)(snd_seq_event_t ev, unsigned char *buf);
	47
	48	/*
	49	* prototypes
	50	*/
	51	static void note_event(snd_midi_event_t dev, snd_seq_event_t ev);
	52	static void one_param_ctrl_event(snd_midi_event_t dev, snd_seq_event_t ev);
	53	static void pitchbend_ctrl_event(snd_midi_event_t dev, snd_seq_event_t ev);
	54	static void two_param_ctrl_event(snd_midi_event_t dev, snd_seq_event_t ev);
	55	static void one_param_event(snd_midi_event_t dev, snd_seq_event_t ev);
	56	static void songpos_event(snd_midi_event_t dev, snd_seq_event_t ev);
	57	static void note_decode(snd_seq_event_t ev, unsigned char buf);
	58	static void one_param_decode(snd_seq_event_t ev, unsigned char buf);
	59	static void pitchbend_decode(snd_seq_event_t ev, unsigned char buf);
	60	static void two_param_decode(snd_seq_event_t ev, unsigned char buf);
	61	static void songpos_decode(snd_seq_event_t ev, unsigned char buf);
	62
	63	/*
	64	* event list
65	*/
66	static struct status_event_list_t {
67	int event;
68	int qlen;
69	event_encode_t encode;
70	event_decode_t decode;
71	} status_event[] = {
72	/* 0x80 - 0xf0 */
73	{SNDRV_SEQ_EVENT_NOTEOFF, 2, note_event, note_decode},
74	{SNDRV_SEQ_EVENT_NOTEON, 2, note_event, note_decode},
75	{SNDRV_SEQ_EVENT_KEYPRESS, 2, note_event, note_decode},
76	{SNDRV_SEQ_EVENT_CONTROLLER, 2, two_param_ctrl_event, two_param_decode},
77	{SNDRV_SEQ_EVENT_PGMCHANGE, 1, one_param_ctrl_event, one_param_decode},
78	{SNDRV_SEQ_EVENT_CHANPRESS, 1, one_param_ctrl_event, one_param_decode},
79	{SNDRV_SEQ_EVENT_PITCHBEND, 2, pitchbend_ctrl_event, pitchbend_decode},
80	{SNDRV_SEQ_EVENT_NONE, 0, NULL, NULL}, /* 0xf0 */
81	/* 0xf0 - 0xff */
82	{SNDRV_SEQ_EVENT_SYSEX, 1, NULL, NULL}, /* sysex: 0xf0 */
83	{SNDRV_SEQ_EVENT_QFRAME, 1, one_param_event, one_param_decode}, /* 0xf1 */
84	{SNDRV_SEQ_EVENT_SONGPOS, 2, songpos_event, songpos_decode}, /* 0xf2 */
85	{SNDRV_SEQ_EVENT_SONGSEL, 1, one_param_event, one_param_decode}, /* 0xf3 */
86	{SNDRV_SEQ_EVENT_NONE, 0, NULL, NULL}, /* 0xf4 */
87	{SNDRV_SEQ_EVENT_NONE, 0, NULL, NULL}, /* 0xf5 */
88	{SNDRV_SEQ_EVENT_TUNE_REQUEST, 0, NULL, NULL}, /* 0xf6 */
89	{SNDRV_SEQ_EVENT_NONE, 0, NULL, NULL}, /* 0xf7 */
90	{SNDRV_SEQ_EVENT_CLOCK, 0, NULL, NULL}, /* 0xf8 */
91	{SNDRV_SEQ_EVENT_NONE, 0, NULL, NULL}, /* 0xf9 */
92	{SNDRV_SEQ_EVENT_START, 0, NULL, NULL}, /* 0xfa */
93	{SNDRV_SEQ_EVENT_CONTINUE, 0, NULL, NULL}, /* 0xfb */
94	{SNDRV_SEQ_EVENT_STOP, 0, NULL, NULL}, /* 0xfc */
95	{SNDRV_SEQ_EVENT_NONE, 0, NULL, NULL}, /* 0xfd */
96	{SNDRV_SEQ_EVENT_SENSING, 0, NULL, NULL}, /* 0xfe */
97	{SNDRV_SEQ_EVENT_RESET, 0, NULL, NULL}, /* 0xff */
98	};
99
100	static int extra_decode_ctrl14(snd_midi_event_t dev, unsigned char buf, int len, snd_seq_event_t *ev);
101	static int extra_decode_xrpn(snd_midi_event_t dev, unsigned char buf, int count, snd_seq_event_t *ev);
102
103	static struct extra_event_list_t {
104	int event;
105	int (decode)(snd_midi_event_t dev, unsigned char buf, int len, snd_seq_event_t ev);
106	} extra_event[] = {
107	{SNDRV_SEQ_EVENT_CONTROL14, extra_decode_ctrl14},
108	{SNDRV_SEQ_EVENT_NONREGPARAM, extra_decode_xrpn},
109	{SNDRV_SEQ_EVENT_REGPARAM, extra_decode_xrpn},
110	};
111
112	/*
113	* new/delete record
114	*/
115
116	int snd_midi_event_new(int bufsize, snd_midi_event_t **rdev)
117	{
118	snd_midi_event_t *dev;
119
120	*rdev = NULL;
121	dev = kcalloc(1, sizeof(*dev), GFP_KERNEL);
122	if (dev == NULL)
123	return -ENOMEM;
124	if (bufsize > 0) {
125	dev->buf = kmalloc(bufsize, GFP_KERNEL);
126	if (dev->buf == NULL) {
127	kfree(dev);
128	return -ENOMEM;
129	}
130	}
131	dev->bufsize = bufsize;
132	dev->lastcmd = 0xff;
133	spin_lock_init(&dev->lock);
134	*rdev = dev;
135	return 0;
136	}
137
138	void snd_midi_event_free(snd_midi_event_t *dev)
139	{
140	if (dev != NULL) {
141	kfree(dev->buf);
142	kfree(dev);
143	}
144	}
145
146	/*
147	* initialize record
148	*/
149	inline static void reset_encode(snd_midi_event_t *dev)
150	{
151	dev->read = 0;
152	dev->qlen = 0;
153	dev->type = 0;
154	}
155
156	void snd_midi_event_reset_encode(snd_midi_event_t *dev)
157	{
158	unsigned long flags;
159
160	spin_lock_irqsave(&dev->lock, flags);
161	reset_encode(dev);
162	spin_unlock_irqrestore(&dev->lock, flags);
163	}
164
165	void snd_midi_event_reset_decode(snd_midi_event_t *dev)
166	{
167	unsigned long flags;
168
169	spin_lock_irqsave(&dev->lock, flags);
170	dev->lastcmd = 0xff;
171	spin_unlock_irqrestore(&dev->lock, flags);
172	}
173
174	void snd_midi_event_init(snd_midi_event_t *dev)
175	{
176	snd_midi_event_reset_encode(dev);
177	snd_midi_event_reset_decode(dev);
178	}
179
180	void snd_midi_event_no_status(snd_midi_event_t *dev, int on)
181	{
182	dev->nostat = on ? 1 : 0;
183	}
184
185	/*
186	* resize buffer
187	*/
188	int snd_midi_event_resize_buffer(snd_midi_event_t *dev, int bufsize)
189	{
190	unsigned char new_buf, old_buf;
191	unsigned long flags;
192
193	if (bufsize == dev->bufsize)
194	return 0;
195	new_buf = kmalloc(bufsize, GFP_KERNEL);
196	if (new_buf == NULL)
197	return -ENOMEM;
198	spin_lock_irqsave(&dev->lock, flags);
199	old_buf = dev->buf;
200	dev->buf = new_buf;
201	dev->bufsize = bufsize;
202	reset_encode(dev);
203	spin_unlock_irqrestore(&dev->lock, flags);
204	kfree(old_buf);
205	return 0;
206	}
207
208	/*
209	* read bytes and encode to sequencer event if finished
210	* return the size of encoded bytes
211	*/
212	long snd_midi_event_encode(snd_midi_event_t dev, unsigned char buf, long count, snd_seq_event_t *ev)
213	{
214	long result = 0;
215	int rc;
216
217	ev->type = SNDRV_SEQ_EVENT_NONE;
218
219	while (count-- > 0) {
220	rc = snd_midi_event_encode_byte(dev, *buf++, ev);
221	result++;
222	if (rc < 0)
223	return rc;
224	else if (rc > 0)
225	return result;
226	}
227
228	return result;
229	}
230
231	/*
232	* read one byte and encode to sequencer event:
233	* return 1 if MIDI bytes are encoded to an event
234	* 0 data is not finished
235	* negative for error
236	*/
237	int snd_midi_event_encode_byte(snd_midi_event_t dev, int c, snd_seq_event_t ev)
238	{
239	int rc = 0;
240	unsigned long flags;
241
242	c &= 0xff;
243
244	if (c >= MIDI_CMD_COMMON_CLOCK) {
245	/* real-time event */
246	ev->type = status_event[ST_SPECIAL + c - 0xf0].event;
247	ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK;
248	ev->flags \|= SNDRV_SEQ_EVENT_LENGTH_FIXED;
249	return 1;
250	}
251
252	spin_lock_irqsave(&dev->lock, flags);
253	if (dev->qlen > 0) {
254	/* rest of command */
255	dev->buf[dev->read++] = c;
256	if (dev->type != ST_SYSEX)
257	dev->qlen--;
258	} else {
259	/* new command */
260	dev->read = 1;
261	if (c & 0x80) {
262	dev->buf[0] = c;
263	if ((c & 0xf0) == 0xf0) /* special events */
264	dev->type = (c & 0x0f) + ST_SPECIAL;
265	else
266	dev->type = (c >> 4) & 0x07;
267	dev->qlen = status_event[dev->type].qlen;
268	} else {
269	/* process this byte as argument */
270	dev->buf[dev->read++] = c;
271	dev->qlen = status_event[dev->type].qlen - 1;
272	}
273	}
274	if (dev->qlen == 0) {
275	ev->type = status_event[dev->type].event;
276	ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK;
277	ev->flags \|= SNDRV_SEQ_EVENT_LENGTH_FIXED;
278	if (status_event[dev->type].encode) /* set data values */
279	status_event[dev->type].encode(dev, ev);
280	rc = 1;
281	} else if (dev->type == ST_SYSEX) {
282	if (c == MIDI_CMD_COMMON_SYSEX_END \|\|
283	dev->read >= dev->bufsize) {
284	ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK;
285	ev->flags \|= SNDRV_SEQ_EVENT_LENGTH_VARIABLE;
286	ev->type = SNDRV_SEQ_EVENT_SYSEX;
287	ev->data.ext.len = dev->read;
288	ev->data.ext.ptr = dev->buf;
289	if (c != MIDI_CMD_COMMON_SYSEX_END)
290	dev->read = 0; /* continue to parse */
291	else
292	reset_encode(dev); /* all parsed */
293	rc = 1;
294	}
295	}
296
297	spin_unlock_irqrestore(&dev->lock, flags);
298	return rc;
299	}
300
301	/* encode note event */
302	static void note_event(snd_midi_event_t dev, snd_seq_event_t ev)
303	{
304	ev->data.note.channel = dev->buf[0] & 0x0f;
305	ev->data.note.note = dev->buf[1];
306	ev->data.note.velocity = dev->buf[2];
307	}
308
309	/* encode one parameter controls */
310	static void one_param_ctrl_event(snd_midi_event_t dev, snd_seq_event_t ev)
311	{
312	ev->data.control.channel = dev->buf[0] & 0x0f;
313	ev->data.control.value = dev->buf[1];
314	}
315
316	/* encode pitch wheel change */
317	static void pitchbend_ctrl_event(snd_midi_event_t dev, snd_seq_event_t ev)
318	{
319	ev->data.control.channel = dev->buf[0] & 0x0f;
320	ev->data.control.value = (int)dev->buf[2] * 128 + (int)dev->buf[1] - 8192;
321	}
322
323	/* encode midi control change */
324	static void two_param_ctrl_event(snd_midi_event_t dev, snd_seq_event_t ev)
325	{
326	ev->data.control.channel = dev->buf[0] & 0x0f;
327	ev->data.control.param = dev->buf[1];
328	ev->data.control.value = dev->buf[2];
329	}
330
331	/* encode one parameter value*/
332	static void one_param_event(snd_midi_event_t dev, snd_seq_event_t ev)
333	{
334	ev->data.control.value = dev->buf[1];
335	}
336
337	/* encode song position */
338	static void songpos_event(snd_midi_event_t dev, snd_seq_event_t ev)
339	{
340	ev->data.control.value = (int)dev->buf[2] * 128 + (int)dev->buf[1];
341	}
342
343	/*
344	* decode from a sequencer event to midi bytes
345	* return the size of decoded midi events
346	*/
347	long snd_midi_event_decode(snd_midi_event_t dev, unsigned char buf, long count, snd_seq_event_t *ev)
348	{
349	unsigned int cmd, type;
350
351	if (ev->type == SNDRV_SEQ_EVENT_NONE)
352	return -ENOENT;
353
354	for (type = 0; type < ARRAY_SIZE(status_event); type++) {
355	if (ev->type == status_event[type].event)
356	goto __found;
357	}
358	for (type = 0; type < ARRAY_SIZE(extra_event); type++) {
359	if (ev->type == extra_event[type].event)
360	return extra_event[type].decode(dev, buf, count, ev);
361	}
362	return -ENOENT;
363
364	__found:
365	if (type >= ST_SPECIAL)
366	cmd = 0xf0 + (type - ST_SPECIAL);
367	else
368	/* data.note.channel and data.control.channel is identical */
369	cmd = 0x80 \| (type << 4) \| (ev->data.note.channel & 0x0f);
370
371
372	if (cmd == MIDI_CMD_COMMON_SYSEX) {
373	snd_midi_event_reset_decode(dev);
374	return snd_seq_expand_var_event(ev, count, buf, 1, 0);
375	} else {
376	int qlen;
377	unsigned char xbuf[4];
378	unsigned long flags;
379
380	spin_lock_irqsave(&dev->lock, flags);
381	if ((cmd & 0xf0) == 0xf0 \|\| dev->lastcmd != cmd \|\| dev->nostat) {
382	dev->lastcmd = cmd;
383	spin_unlock_irqrestore(&dev->lock, flags);
384	xbuf[0] = cmd;
385	if (status_event[type].decode)
386	status_event[type].decode(ev, xbuf + 1);
387	qlen = status_event[type].qlen + 1;
388	} else {
389	spin_unlock_irqrestore(&dev->lock, flags);
390	if (status_event[type].decode)
391	status_event[type].decode(ev, xbuf + 0);
392	qlen = status_event[type].qlen;
393	}
394	if (count < qlen)
395	return -ENOMEM;
396	memcpy(buf, xbuf, qlen);
397	return qlen;
398	}
399	}
400
401
402	/* decode note event */
403	static void note_decode(snd_seq_event_t ev, unsigned char buf)
404	{
405	buf[0] = ev->data.note.note & 0x7f;
406	buf[1] = ev->data.note.velocity & 0x7f;
407	}
408
409	/* decode one parameter controls */
410	static void one_param_decode(snd_seq_event_t ev, unsigned char buf)
411	{
412	buf[0] = ev->data.control.value & 0x7f;
413	}
414
415	/* decode pitch wheel change */
416	static void pitchbend_decode(snd_seq_event_t ev, unsigned char buf)
417	{
418	int value = ev->data.control.value + 8192;
419	buf[0] = value & 0x7f;
420	buf[1] = (value >> 7) & 0x7f;
421	}
422
423	/* decode midi control change */
424	static void two_param_decode(snd_seq_event_t ev, unsigned char buf)
425	{
426	buf[0] = ev->data.control.param & 0x7f;
427	buf[1] = ev->data.control.value & 0x7f;
428	}
429
430	/* decode song position */
431	static void songpos_decode(snd_seq_event_t ev, unsigned char buf)
432	{
433	buf[0] = ev->data.control.value & 0x7f;
434	buf[1] = (ev->data.control.value >> 7) & 0x7f;
435	}
436
437	/* decode 14bit control */
438	static int extra_decode_ctrl14(snd_midi_event_t dev, unsigned char buf, int count, snd_seq_event_t *ev)
439	{
440	unsigned char cmd;
441	int idx = 0;
442
443	cmd = MIDI_CMD_CONTROL\|(ev->data.control.channel & 0x0f);
444	if (ev->data.control.param < 0x20) {
445	if (count < 4)
446	return -ENOMEM;
447	if (dev->nostat && count < 6)
448	return -ENOMEM;
449	if (cmd != dev->lastcmd \|\| dev->nostat) {
450	if (count < 5)
451	return -ENOMEM;
452	buf[idx++] = dev->lastcmd = cmd;
453	}
454	buf[idx++] = ev->data.control.param;
455	buf[idx++] = (ev->data.control.value >> 7) & 0x7f;
456	if (dev->nostat)
457	buf[idx++] = cmd;
458	buf[idx++] = ev->data.control.param + 0x20;
459	buf[idx++] = ev->data.control.value & 0x7f;
460	} else {
461	if (count < 2)
462	return -ENOMEM;
463	if (cmd != dev->lastcmd \|\| dev->nostat) {
464	if (count < 3)
465	return -ENOMEM;
466	buf[idx++] = dev->lastcmd = cmd;
467	}
468	buf[idx++] = ev->data.control.param & 0x7f;
469	buf[idx++] = ev->data.control.value & 0x7f;
470	}
471	return idx;
472	}
473
474	/* decode reg/nonreg param */
475	static int extra_decode_xrpn(snd_midi_event_t dev, unsigned char buf, int count, snd_seq_event_t *ev)
476	{
477	unsigned char cmd;
478	char *cbytes;
479	static char cbytes_nrpn[4] = { MIDI_CTL_NONREG_PARM_NUM_MSB,
480	MIDI_CTL_NONREG_PARM_NUM_LSB,
481	MIDI_CTL_MSB_DATA_ENTRY,
482	MIDI_CTL_LSB_DATA_ENTRY };
483	static char cbytes_rpn[4] = { MIDI_CTL_REGIST_PARM_NUM_MSB,
484	MIDI_CTL_REGIST_PARM_NUM_LSB,
485	MIDI_CTL_MSB_DATA_ENTRY,
486	MIDI_CTL_LSB_DATA_ENTRY };
487	unsigned char bytes[4];
488	int idx = 0, i;
489
490	if (count < 8)
491	return -ENOMEM;
492	if (dev->nostat && count < 12)
493	return -ENOMEM;
494	cmd = MIDI_CMD_CONTROL\|(ev->data.control.channel & 0x0f);
495	bytes[0] = ev->data.control.param & 0x007f;
496	bytes[1] = (ev->data.control.param & 0x3f80) >> 7;
497	bytes[2] = ev->data.control.value & 0x007f;
498	bytes[3] = (ev->data.control.value & 0x3f80) >> 7;
499	if (cmd != dev->lastcmd && !dev->nostat) {
500	if (count < 9)
501	return -ENOMEM;
502	buf[idx++] = dev->lastcmd = cmd;
503	}
504	cbytes = ev->type == SNDRV_SEQ_EVENT_NONREGPARAM ? cbytes_nrpn : cbytes_rpn;
505	for (i = 0; i < 4; i++) {
506	if (dev->nostat)
507	buf[idx++] = dev->lastcmd = cmd;
508	buf[idx++] = cbytes[i];
509	buf[idx++] = bytes[i];
510	}
511	return idx;
512	}
513
514	/*
515	* exports
516	*/
517
518	EXPORT_SYMBOL(snd_midi_event_new);
519	EXPORT_SYMBOL(snd_midi_event_free);
520	EXPORT_SYMBOL(snd_midi_event_resize_buffer);
521	EXPORT_SYMBOL(snd_midi_event_init);
522	EXPORT_SYMBOL(snd_midi_event_reset_encode);
523	EXPORT_SYMBOL(snd_midi_event_reset_decode);
524	EXPORT_SYMBOL(snd_midi_event_no_status);
525	EXPORT_SYMBOL(snd_midi_event_encode);
526	EXPORT_SYMBOL(snd_midi_event_encode_byte);
527	EXPORT_SYMBOL(snd_midi_event_decode);
528
529	static int __init alsa_seq_midi_event_init(void)
530	{
531	return 0;
532	}
533
534	static void __exit alsa_seq_midi_event_exit(void)
535	{
536	}
537
538	module_init(alsa_seq_midi_event_init)
539	module_exit(alsa_seq_midi_event_exit)