sound/core/seq/seq_midi_event.c

   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 /*
  45  * prototypes
  46  */
  47 static void note_event(struct snd_midi_event *dev, struct snd_seq_event *ev);
  48 static void one_param_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev);
  49 static void pitchbend_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev);
  50 static void two_param_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev);
  51 static void one_param_event(struct snd_midi_event *dev, struct snd_seq_event *ev);
  52 static void songpos_event(struct snd_midi_event *dev, struct snd_seq_event *ev);
  53 static void note_decode(struct snd_seq_event *ev, unsigned char *buf);
  54 static void one_param_decode(struct snd_seq_event *ev, unsigned char *buf);
  55 static void pitchbend_decode(struct snd_seq_event *ev, unsigned char *buf);
  56 static void two_param_decode(struct snd_seq_event *ev, unsigned char *buf);
  57 static void songpos_decode(struct snd_seq_event *ev, unsigned char *buf);
  58
  59 /*
  60  * event list
  61  */
  62 static struct status_event_list {
  63         int event;
  64         int qlen;
  65         void (*encode)(struct snd_midi_event *dev, struct snd_seq_event *ev);
  66         void (*decode)(struct snd_seq_event *ev, unsigned char *buf);
  67 } status_event[] = {
  68         /* 0x80 - 0xf0 */
  69         {SNDRV_SEQ_EVENT_NOTEOFF,       2, note_event, note_decode},
  70         {SNDRV_SEQ_EVENT_NOTEON,        2, note_event, note_decode},
  71         {SNDRV_SEQ_EVENT_KEYPRESS,      2, note_event, note_decode},
  72         {SNDRV_SEQ_EVENT_CONTROLLER,    2, two_param_ctrl_event, two_param_decode},
  73         {SNDRV_SEQ_EVENT_PGMCHANGE,     1, one_param_ctrl_event, one_param_decode},
  74         {SNDRV_SEQ_EVENT_CHANPRESS,     1, one_param_ctrl_event, one_param_decode},
  75         {SNDRV_SEQ_EVENT_PITCHBEND,     2, pitchbend_ctrl_event, pitchbend_decode},
  76         {SNDRV_SEQ_EVENT_NONE,          0, NULL, NULL}, /* 0xf0 */
  77         /* 0xf0 - 0xff */
  78         {SNDRV_SEQ_EVENT_SYSEX,         1, NULL, NULL}, /* sysex: 0xf0 */
  79         {SNDRV_SEQ_EVENT_QFRAME,        1, one_param_event, one_param_decode}, /* 0xf1 */
  80         {SNDRV_SEQ_EVENT_SONGPOS,       2, songpos_event, songpos_decode}, /* 0xf2 */
  81         {SNDRV_SEQ_EVENT_SONGSEL,       1, one_param_event, one_param_decode}, /* 0xf3 */
  82         {SNDRV_SEQ_EVENT_NONE,          0, NULL, NULL}, /* 0xf4 */
  83         {SNDRV_SEQ_EVENT_NONE,          0, NULL, NULL}, /* 0xf5 */
  84         {SNDRV_SEQ_EVENT_TUNE_REQUEST,  0, NULL, NULL}, /* 0xf6 */
  85         {SNDRV_SEQ_EVENT_NONE,          0, NULL, NULL}, /* 0xf7 */
  86         {SNDRV_SEQ_EVENT_CLOCK,         0, NULL, NULL}, /* 0xf8 */
  87         {SNDRV_SEQ_EVENT_NONE,          0, NULL, NULL}, /* 0xf9 */
  88         {SNDRV_SEQ_EVENT_START,         0, NULL, NULL}, /* 0xfa */
  89         {SNDRV_SEQ_EVENT_CONTINUE,      0, NULL, NULL}, /* 0xfb */
  90         {SNDRV_SEQ_EVENT_STOP,          0, NULL, NULL}, /* 0xfc */
  91         {SNDRV_SEQ_EVENT_NONE,          0, NULL, NULL}, /* 0xfd */
  92         {SNDRV_SEQ_EVENT_SENSING,       0, NULL, NULL}, /* 0xfe */
  93         {SNDRV_SEQ_EVENT_RESET,         0, NULL, NULL}, /* 0xff */
  94 };
  95
  96 static int extra_decode_ctrl14(struct snd_midi_event *dev, unsigned char *buf, int len,
  97                                struct snd_seq_event *ev);
  98 static int extra_decode_xrpn(struct snd_midi_event *dev, unsigned char *buf, int count,
  99                              struct snd_seq_event *ev);
 100
 101 static struct extra_event_list {
 102         int event;
 103         int (*decode)(struct snd_midi_event *dev, unsigned char *buf, int len,
 104                       struct snd_seq_event *ev);
 105 } extra_event[] = {
 106         {SNDRV_SEQ_EVENT_CONTROL14, extra_decode_ctrl14},
 107         {SNDRV_SEQ_EVENT_NONREGPARAM, extra_decode_xrpn},
 108         {SNDRV_SEQ_EVENT_REGPARAM, extra_decode_xrpn},
 109 };
 110
 111 /*
 112  *  new/delete record
 113  */
 114
 115 int snd_midi_event_new(int bufsize, struct snd_midi_event **rdev)
 116 {
 117         struct snd_midi_event *dev;
 118
 119         *rdev = NULL;
 120         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 121         if (dev == NULL)
 122                 return -ENOMEM;
 123         if (bufsize > 0) {
 124                 dev->buf = kmalloc(bufsize, GFP_KERNEL);
 125                 if (dev->buf == NULL) {
 126                         kfree(dev);
 127                         return -ENOMEM;
 128                 }
 129         }
 130         dev->bufsize = bufsize;
 131         dev->lastcmd = 0xff;
 132         spin_lock_init(&dev->lock);
 133         *rdev = dev;
 134         return 0;
 135 }
 136
 137 void snd_midi_event_free(struct snd_midi_event *dev)
 138 {
 139         if (dev != NULL) {
 140                 kfree(dev->buf);
 141                 kfree(dev);
 142         }
 143 }
 144
 145 /*
 146  * initialize record
 147  */
 148 static inline void reset_encode(struct snd_midi_event *dev)
 149 {
 150         dev->read = 0;
 151         dev->qlen = 0;
 152         dev->type = 0;
 153 }
 154
 155 void snd_midi_event_reset_encode(struct snd_midi_event *dev)
 156 {
 157         unsigned long flags;
 158
 159         spin_lock_irqsave(&dev->lock, flags);
 160         reset_encode(dev);
 161         spin_unlock_irqrestore(&dev->lock, flags);
 162 }
 163
 164 void snd_midi_event_reset_decode(struct snd_midi_event *dev)
 165 {
 166         unsigned long flags;
 167
 168         spin_lock_irqsave(&dev->lock, flags);
 169         dev->lastcmd = 0xff;
 170         spin_unlock_irqrestore(&dev->lock, flags);
 171 }
 172
 173 #if 0
 174 void snd_midi_event_init(struct snd_midi_event *dev)
 175 {
 176         snd_midi_event_reset_encode(dev);
 177         snd_midi_event_reset_decode(dev);
 178 }
 179 #endif  /*  0  */
 180
 181 void snd_midi_event_no_status(struct snd_midi_event *dev, int on)
 182 {
 183         dev->nostat = on ? 1 : 0;
 184 }
 185
 186 /*
 187  * resize buffer
 188  */
 189 #if 0
 190 int snd_midi_event_resize_buffer(struct snd_midi_event *dev, int bufsize)
 191 {
 192         unsigned char *new_buf, *old_buf;
 193         unsigned long flags;
 194
 195         if (bufsize == dev->bufsize)
 196                 return 0;
 197         new_buf = kmalloc(bufsize, GFP_KERNEL);
 198         if (new_buf == NULL)
 199                 return -ENOMEM;
 200         spin_lock_irqsave(&dev->lock, flags);
 201         old_buf = dev->buf;
 202         dev->buf = new_buf;
 203         dev->bufsize = bufsize;
 204         reset_encode(dev);
 205         spin_unlock_irqrestore(&dev->lock, flags);
 206         kfree(old_buf);
 207         return 0;
 208 }
 209 #endif  /*  0  */
 210
 211 /*
 212  *  read bytes and encode to sequencer event if finished
 213  *  return the size of encoded bytes
 214  */
 215 long snd_midi_event_encode(struct snd_midi_event *dev, unsigned char *buf, long count,
 216                            struct snd_seq_event *ev)
 217 {
 218         long result = 0;
 219         int rc;
 220
 221         ev->type = SNDRV_SEQ_EVENT_NONE;
 222
 223         while (count-- > 0) {
 224                 rc = snd_midi_event_encode_byte(dev, *buf++, ev);
 225                 result++;
 226                 if (rc < 0)
 227                         return rc;
 228                 else if (rc > 0)
 229                         return result;
 230         }
 231
 232         return result;
 233 }
 234
 235 /*
 236  *  read one byte and encode to sequencer event:
 237  *  return 1 if MIDI bytes are encoded to an event
 238  *         0 data is not finished
 239  *         negative for error
 240  */
 241 int snd_midi_event_encode_byte(struct snd_midi_event *dev, int c,
 242                                struct snd_seq_event *ev)
 243 {
 244         int rc = 0;
 245         unsigned long flags;
 246
 247         c &= 0xff;
 248
 249         if (c >= MIDI_CMD_COMMON_CLOCK) {
 250                 /* real-time event */
 251                 ev->type = status_event[ST_SPECIAL + c - 0xf0].event;
 252                 ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK;
 253                 ev->flags |= SNDRV_SEQ_EVENT_LENGTH_FIXED;
 254                 return 1;
 255         }
 256
 257         spin_lock_irqsave(&dev->lock, flags);
 258         if (dev->qlen > 0) {
 259                 /* rest of command */
 260                 dev->buf[dev->read++] = c;
 261                 if (dev->type != ST_SYSEX)
 262                         dev->qlen--;
 263         } else {
 264                 /* new command */
 265                 dev->read = 1;
 266                 if (c & 0x80) {
 267                         dev->buf[0] = c;
 268                         if ((c & 0xf0) == 0xf0) /* special events */
 269                                 dev->type = (c & 0x0f) + ST_SPECIAL;
 270                         else
 271                                 dev->type = (c >> 4) & 0x07;
 272                         dev->qlen = status_event[dev->type].qlen;
 273                 } else {
 274                         /* process this byte as argument */
 275                         dev->buf[dev->read++] = c;
 276                         dev->qlen = status_event[dev->type].qlen - 1;
 277                 }
 278         }
 279         if (dev->qlen == 0) {
 280                 ev->type = status_event[dev->type].event;
 281                 ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK;
 282                 ev->flags |= SNDRV_SEQ_EVENT_LENGTH_FIXED;
 283                 if (status_event[dev->type].encode) /* set data values */
 284                         status_event[dev->type].encode(dev, ev);
 285                 rc = 1;
 286         } else  if (dev->type == ST_SYSEX) {
 287                 if (c == MIDI_CMD_COMMON_SYSEX_END ||
 288                     dev->read >= dev->bufsize) {
 289                         ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK;
 290                         ev->flags |= SNDRV_SEQ_EVENT_LENGTH_VARIABLE;
 291                         ev->type = SNDRV_SEQ_EVENT_SYSEX;
 292                         ev->data.ext.len = dev->read;
 293                         ev->data.ext.ptr = dev->buf;
 294                         if (c != MIDI_CMD_COMMON_SYSEX_END)
 295                                 dev->read = 0; /* continue to parse */
 296                         else
 297                                 reset_encode(dev); /* all parsed */
 298                         rc = 1;
 299                 }
 300         }
 301
 302         spin_unlock_irqrestore(&dev->lock, flags);
 303         return rc;
 304 }
 305
 306 /* encode note event */
 307 static void note_event(struct snd_midi_event *dev, struct snd_seq_event *ev)
 308 {
 309         ev->data.note.channel = dev->buf[0] & 0x0f;
 310         ev->data.note.note = dev->buf[1];
 311         ev->data.note.velocity = dev->buf[2];
 312 }
 313
 314 /* encode one parameter controls */
 315 static void one_param_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev)
 316 {
 317         ev->data.control.channel = dev->buf[0] & 0x0f;
 318         ev->data.control.value = dev->buf[1];
 319 }
 320
 321 /* encode pitch wheel change */
 322 static void pitchbend_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev)
 323 {
 324         ev->data.control.channel = dev->buf[0] & 0x0f;
 325         ev->data.control.value = (int)dev->buf[2] * 128 + (int)dev->buf[1] - 8192;
 326 }
 327
 328 /* encode midi control change */
 329 static void two_param_ctrl_event(struct snd_midi_event *dev, struct snd_seq_event *ev)
 330 {
 331         ev->data.control.channel = dev->buf[0] & 0x0f;
 332         ev->data.control.param = dev->buf[1];
 333         ev->data.control.value = dev->buf[2];
 334 }
 335
 336 /* encode one parameter value*/
 337 static void one_param_event(struct snd_midi_event *dev, struct snd_seq_event *ev)
 338 {
 339         ev->data.control.value = dev->buf[1];
 340 }
 341
 342 /* encode song position */
 343 static void songpos_event(struct snd_midi_event *dev, struct snd_seq_event *ev)
 344 {
 345         ev->data.control.value = (int)dev->buf[2] * 128 + (int)dev->buf[1];
 346 }
 347
 348 /*
 349  * decode from a sequencer event to midi bytes
 350  * return the size of decoded midi events
 351  */
 352 long snd_midi_event_decode(struct snd_midi_event *dev, unsigned char *buf, long count,
 353                            struct snd_seq_event *ev)
 354 {
 355         unsigned int cmd, type;
 356
 357         if (ev->type == SNDRV_SEQ_EVENT_NONE)
 358                 return -ENOENT;
 359
 360         for (type = 0; type < ARRAY_SIZE(status_event); type++) {
 361                 if (ev->type == status_event[type].event)
 362                         goto __found;
 363         }
 364         for (type = 0; type < ARRAY_SIZE(extra_event); type++) {
 365                 if (ev->type == extra_event[type].event)
 366                         return extra_event[type].decode(dev, buf, count, ev);
 367         }
 368         return -ENOENT;
 369
 370       __found:
 371         if (type >= ST_SPECIAL)
 372                 cmd = 0xf0 + (type - ST_SPECIAL);
 373         else
 374                 /* data.note.channel and data.control.channel is identical */
 375                 cmd = 0x80 | (type << 4) | (ev->data.note.channel & 0x0f);
 376
 377
 378         if (cmd == MIDI_CMD_COMMON_SYSEX) {
 379                 snd_midi_event_reset_decode(dev);
 380                 return snd_seq_expand_var_event(ev, count, buf, 1, 0);
 381         } else {
 382                 int qlen;
 383                 unsigned char xbuf[4];
 384                 unsigned long flags;
 385
 386                 spin_lock_irqsave(&dev->lock, flags);
 387                 if ((cmd & 0xf0) == 0xf0 || dev->lastcmd != cmd || dev->nostat) {
 388                         dev->lastcmd = cmd;
 389                         spin_unlock_irqrestore(&dev->lock, flags);
 390                         xbuf[0] = cmd;
 391                         if (status_event[type].decode)
 392                                 status_event[type].decode(ev, xbuf + 1);
 393                         qlen = status_event[type].qlen + 1;
 394                 } else {
 395                         spin_unlock_irqrestore(&dev->lock, flags);
 396                         if (status_event[type].decode)
 397                                 status_event[type].decode(ev, xbuf + 0);
 398                         qlen = status_event[type].qlen;
 399                 }
 400                 if (count < qlen)
 401                         return -ENOMEM;
 402                 memcpy(buf, xbuf, qlen);
 403                 return qlen;
 404         }
 405 }
 406
 407
 408 /* decode note event */
 409 static void note_decode(struct snd_seq_event *ev, unsigned char *buf)
 410 {
 411         buf[0] = ev->data.note.note & 0x7f;
 412         buf[1] = ev->data.note.velocity & 0x7f;
 413 }
 414
 415 /* decode one parameter controls */
 416 static void one_param_decode(struct snd_seq_event *ev, unsigned char *buf)
 417 {
 418         buf[0] = ev->data.control.value & 0x7f;
 419 }
 420
 421 /* decode pitch wheel change */
 422 static void pitchbend_decode(struct snd_seq_event *ev, unsigned char *buf)
 423 {
 424         int value = ev->data.control.value + 8192;
 425         buf[0] = value & 0x7f;
 426         buf[1] = (value >> 7) & 0x7f;
 427 }
 428
 429 /* decode midi control change */
 430 static void two_param_decode(struct snd_seq_event *ev, unsigned char *buf)
 431 {
 432         buf[0] = ev->data.control.param & 0x7f;
 433         buf[1] = ev->data.control.value & 0x7f;
 434 }
 435
 436 /* decode song position */
 437 static void songpos_decode(struct snd_seq_event *ev, unsigned char *buf)
 438 {
 439         buf[0] = ev->data.control.value & 0x7f;
 440         buf[1] = (ev->data.control.value >> 7) & 0x7f;
 441 }
 442
 443 /* decode 14bit control */
 444 static int extra_decode_ctrl14(struct snd_midi_event *dev, unsigned char *buf,
 445                                int count, struct snd_seq_event *ev)
 446 {
 447         unsigned char cmd;
 448         int idx = 0;
 449
 450         cmd = MIDI_CMD_CONTROL|(ev->data.control.channel & 0x0f);
 451         if (ev->data.control.param < 0x20) {
 452                 if (count < 4)
 453                         return -ENOMEM;
 454                 if (dev->nostat && count < 6)
 455                         return -ENOMEM;
 456                 if (cmd != dev->lastcmd || dev->nostat) {
 457                         if (count < 5)
 458                                 return -ENOMEM;
 459                         buf[idx++] = dev->lastcmd = cmd;
 460                 }
 461                 buf[idx++] = ev->data.control.param;
 462                 buf[idx++] = (ev->data.control.value >> 7) & 0x7f;
 463                 if (dev->nostat)
 464                         buf[idx++] = cmd;
 465                 buf[idx++] = ev->data.control.param + 0x20;
 466                 buf[idx++] = ev->data.control.value & 0x7f;
 467         } else {
 468                 if (count < 2)
 469                         return -ENOMEM;
 470                 if (cmd != dev->lastcmd || dev->nostat) {
 471                         if (count < 3)
 472                                 return -ENOMEM;
 473                         buf[idx++] = dev->lastcmd = cmd;
 474                 }
 475                 buf[idx++] = ev->data.control.param & 0x7f;
 476                 buf[idx++] = ev->data.control.value & 0x7f;
 477         }
 478         return idx;
 479 }
 480
 481 /* decode reg/nonreg param */
 482 static int extra_decode_xrpn(struct snd_midi_event *dev, unsigned char *buf,
 483                              int count, struct snd_seq_event *ev)
 484 {
 485         unsigned char cmd;
 486         char *cbytes;
 487         static char cbytes_nrpn[4] = { MIDI_CTL_NONREG_PARM_NUM_MSB,
 488                                        MIDI_CTL_NONREG_PARM_NUM_LSB,
 489                                        MIDI_CTL_MSB_DATA_ENTRY,
 490                                        MIDI_CTL_LSB_DATA_ENTRY };
 491         static char cbytes_rpn[4] =  { MIDI_CTL_REGIST_PARM_NUM_MSB,
 492                                        MIDI_CTL_REGIST_PARM_NUM_LSB,
 493                                        MIDI_CTL_MSB_DATA_ENTRY,
 494                                        MIDI_CTL_LSB_DATA_ENTRY };
 495         unsigned char bytes[4];
 496         int idx = 0, i;
 497
 498         if (count < 8)
 499                 return -ENOMEM;
 500         if (dev->nostat && count < 12)
 501                 return -ENOMEM;
 502         cmd = MIDI_CMD_CONTROL|(ev->data.control.channel & 0x0f);
 503         bytes[0] = ev->data.control.param & 0x007f;
 504         bytes[1] = (ev->data.control.param & 0x3f80) >> 7;
 505         bytes[2] = ev->data.control.value & 0x007f;
 506         bytes[3] = (ev->data.control.value & 0x3f80) >> 7;
 507         if (cmd != dev->lastcmd && !dev->nostat) {
 508                 if (count < 9)
 509                         return -ENOMEM;
 510                 buf[idx++] = dev->lastcmd = cmd;
 511         }
 512         cbytes = ev->type == SNDRV_SEQ_EVENT_NONREGPARAM ? cbytes_nrpn : cbytes_rpn;
 513         for (i = 0; i < 4; i++) {
 514                 if (dev->nostat)
 515                         buf[idx++] = dev->lastcmd = cmd;
 516                 buf[idx++] = cbytes[i];
 517                 buf[idx++] = bytes[i];
 518         }
 519         return idx;
 520 }
 521
 522 /*
 523  *  exports
 524  */
 525
 526 EXPORT_SYMBOL(snd_midi_event_new);
 527 EXPORT_SYMBOL(snd_midi_event_free);
 528 EXPORT_SYMBOL(snd_midi_event_reset_encode);
 529 EXPORT_SYMBOL(snd_midi_event_reset_decode);
 530 EXPORT_SYMBOL(snd_midi_event_no_status);
 531 EXPORT_SYMBOL(snd_midi_event_encode);
 532 EXPORT_SYMBOL(snd_midi_event_encode_byte);
 533 EXPORT_SYMBOL(snd_midi_event_decode);
 534
 535 static int __init alsa_seq_midi_event_init(void)
 536 {
 537         return 0;
 538 }
 539
 540 static void __exit alsa_seq_midi_event_exit(void)
 541 {
 542 }
 543
 544 module_init(alsa_seq_midi_event_init)
 545 module_exit(alsa_seq_midi_event_exit)