/* * MIDI byte <-> sequencer event coder * * Copyright (C) 1998,99 Takashi Iwai , * Jaroslav Kysela * * 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 #include #include #include #include #include #include #include MODULE_AUTHOR("Takashi Iwai , Jaroslav Kysela "); MODULE_DESCRIPTION("MIDI byte <-> sequencer event coder"); MODULE_LICENSE("GPL"); /* event type, index into status_event[] */ /* from 0 to 6 are normal commands (note off, on, etc.) for 0x9?-0xe? */ #define ST_INVALID 7 #define ST_SPECIAL 8 #define ST_SYSEX ST_SPECIAL /* from 8 to 15 are events for 0xf0-0xf7 */ /* * prototypes */ static void note_event(struct snd_midi_event *dev, struct snd_seq_event *ev); static void one_param_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev); static void pitchbend_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev); static void two_param_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev); static void one_param_event(struct snd_midi_event *dev, struct snd_seq_event *ev); static void songpos_event(struct snd_midi_event *dev, struct snd_seq_event *ev); static void note_decode(struct snd_seq_event *ev, unsigned char *buf); static void one_param_decode(struct snd_seq_event *ev, unsigned char *buf); static void pitchbend_decode(struct snd_seq_event *ev, unsigned char *buf); static void two_param_decode(struct snd_seq_event *ev, unsigned char *buf); static void songpos_decode(struct snd_seq_event *ev, unsigned char *buf); /* * event list */ static struct status_event_list { int event; int qlen; void (*encode)(struct snd_midi_event *dev, struct snd_seq_event *ev); void (*decode)(struct snd_seq_event *ev, unsigned char *buf); } status_event[] = { /* 0x80 - 0xef */ {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}, /* invalid */ {SNDRV_SEQ_EVENT_NONE, -1, NULL, NULL}, /* 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, -1, NULL, NULL}, /* 0xf4 */ {SNDRV_SEQ_EVENT_NONE, -1, NULL, NULL}, /* 0xf5 */ {SNDRV_SEQ_EVENT_TUNE_REQUEST, 0, NULL, NULL}, /* 0xf6 */ {SNDRV_SEQ_EVENT_NONE, -1, NULL, NULL}, /* 0xf7 */ {SNDRV_SEQ_EVENT_CLOCK, 0, NULL, NULL}, /* 0xf8 */ {SNDRV_SEQ_EVENT_NONE, -1, 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, -1, NULL, NULL}, /* 0xfd */ {SNDRV_SEQ_EVENT_SENSING, 0, NULL, NULL}, /* 0xfe */ {SNDRV_SEQ_EVENT_RESET, 0, NULL, NULL}, /* 0xff */ }; static int extra_decode_ctrl14(struct snd_midi_event *dev, unsigned char *buf, int len, struct snd_seq_event *ev); static int extra_decode_xrpn(struct snd_midi_event *dev, unsigned char *buf, int count, struct snd_seq_event *ev); static struct extra_event_list { int event; int (*decode)(struct snd_midi_event *dev, unsigned char *buf, int len, struct snd_seq_event *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, struct snd_midi_event **rdev) { struct snd_midi_event *dev; *rdev = NULL; dev = kzalloc(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; dev->type = ST_INVALID; spin_lock_init(&dev->lock); *rdev = dev; return 0; } void snd_midi_event_free(struct snd_midi_event *dev) { if (dev != NULL) { kfree(dev->buf); kfree(dev); } } /* * initialize record */ static inline void reset_encode(struct snd_midi_event *dev) { dev->read = 0; dev->qlen = 0; dev->type = ST_INVALID; } void snd_midi_event_reset_encode(struct snd_midi_event *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(struct snd_midi_event *dev) { unsigned long flags; spin_lock_irqsave(&dev->lock, flags); dev->lastcmd = 0xff; spin_unlock_irqrestore(&dev->lock, flags); } #if 0 void snd_midi_event_init(struct snd_midi_event *dev) { snd_midi_event_reset_encode(dev); snd_midi_event_reset_decode(dev); } #endif /* 0 */ void snd_midi_event_no_status(struct snd_midi_event *dev, int on) { dev->nostat = on ? 1 : 0; } /* * resize buffer */ #if 0 int snd_midi_event_resize_buffer(struct snd_midi_event *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; } #endif /* 0 */ /* * read bytes and encode to sequencer event if finished * return the size of encoded bytes */ long snd_midi_event_encode(struct snd_midi_event *dev, unsigned char *buf, long count, struct snd_seq_event *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(struct snd_midi_event *dev, int c, struct snd_seq_event *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 ev->type != SNDRV_SEQ_EVENT_NONE; } spin_lock_irqsave(&dev->lock, flags); if ((c & 0x80) && (c != MIDI_CMD_COMMON_SYSEX_END || dev->type != ST_SYSEX)) { /* new command */ dev->buf[0] = c; if ((c & 0xf0) == 0xf0) /* system messages */ dev->type = (c & 0x0f) + ST_SPECIAL; else dev->type = (c >> 4) & 0x07; dev->read = 1; dev->qlen = status_event[dev->type].qlen; } else { if (dev->qlen > 0) { /* rest of command */ dev->buf[dev->read++] = c; if (dev->type != ST_SYSEX) dev->qlen--; } else { /* running status */ dev->buf[1] = c; dev->qlen = status_event[dev->type].qlen - 1; dev->read = 2; } } 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); if (dev->type >= ST_SPECIAL) dev->type = ST_INVALID; 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(struct snd_midi_event *dev, struct snd_seq_event *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(struct snd_midi_event *dev, struct snd_seq_event *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(struct snd_midi_event *dev, struct snd_seq_event *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(struct snd_midi_event *dev, struct snd_seq_event *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(struct snd_midi_event *dev, struct snd_seq_event *ev) { ev->data.control.value = dev->buf[1]; } /* encode song position */ static void songpos_event(struct snd_midi_event *dev, struct snd_seq_event *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(struct snd_midi_event *dev, unsigned char *buf, long count, struct snd_seq_event *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(struct snd_seq_event *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(struct snd_seq_event *ev, unsigned char *buf) { buf[0] = ev->data.control.value & 0x7f; } /* decode pitch wheel change */ static void pitchbend_decode(struct snd_seq_event *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(struct snd_seq_event *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(struct snd_seq_event *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(struct snd_midi_event *dev, unsigned char *buf, int count, struct snd_seq_event *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(struct snd_midi_event *dev, unsigned char *buf, int count, struct snd_seq_event *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 & 0x3f80) >> 7; bytes[1] = ev->data.control.param & 0x007f; bytes[2] = (ev->data.control.value & 0x3f80) >> 7; bytes[3] = ev->data.control.value & 0x007f; 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_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)