Linux Audio

Check our new training course

Embedded Linux Audio

Check our new training course
with Creative Commons CC-BY-SA
lecture materials

Bootlin logo

Elixir Cross Referencer

Loading...
  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
/*
 *  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 <linux/init.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/module.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(struct snd_midi_op *ops, void *drv,
		     struct snd_midi_channel *chan,
		     int note, int vel);
static void do_control(struct snd_midi_op *ops, void *private,
		       struct snd_midi_channel_set *chset,
		       struct snd_midi_channel *chan,
		       int control, int value);
static void rpn(struct snd_midi_op *ops, void *drv, struct snd_midi_channel *chan,
		struct snd_midi_channel_set *chset);
static void nrpn(struct snd_midi_op *ops, void *drv, struct snd_midi_channel *chan,
		 struct snd_midi_channel_set *chset);
static void sysex(struct snd_midi_op *ops, void *private, unsigned char *sysex,
		  int len, struct snd_midi_channel_set *chset);
static void all_sounds_off(struct snd_midi_op *ops, void *private,
			   struct snd_midi_channel *chan);
static void all_notes_off(struct snd_midi_op *ops, void *private,
			  struct snd_midi_channel *chan);
static void snd_midi_reset_controllers(struct snd_midi_channel *chan);
static void reset_all_channels(struct snd_midi_channel_set *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 controllers 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(struct snd_midi_op *ops,
		       struct snd_seq_event *ev,
		       struct snd_midi_channel_set *chanset)
{
	struct snd_midi_channel *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 controller 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 controller 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_ECHO:
	not_yet:
	default:
		/*snd_printd("Unimplemented event %d\n", ev->type);*/
		break;
	}
}


/*
 * release note
 */
static void
note_off(struct snd_midi_op *ops, void *drv, struct snd_midi_channel *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 controller and pass
 * events that need to take place immediately to the driver.
 */
static void
do_control(struct snd_midi_op *ops, void *drv, struct snd_midi_channel_set *chset,
	   struct snd_midi_channel *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)
			ops->control(drv, control, chan);
		break;
	}
}


/*
 * initialize the MIDI status
 */
void
snd_midi_channel_set_clear(struct snd_midi_channel_set *chset)
{
	int i;

	chset->midi_mode = SNDRV_MIDI_MODE_GM;
	chset->gs_master_volume = 127;

	for (i = 0; i < chset->max_channels; i++) {
		struct snd_midi_channel *chan = chset->channels + i;
		memset(chan->note, 0, sizeof(chan->note));

		chan->midi_aftertouch = 0;
		chan->midi_pressure = 0;
		chan->midi_program = 0;
		chan->midi_pitchbend = 0;
		snd_midi_reset_controllers(chan);
		chan->gm_rpn_pitch_bend_range = 256; /* 2 semitones */
		chan->gm_rpn_fine_tuning = 0;
		chan->gm_rpn_coarse_tuning = 0;

		if (i == 9)
			chan->drum_channel = 1;
		else
			chan->drum_channel = 0;
	}
}

/*
 * Process a rpn message.
 */
static void
rpn(struct snd_midi_op *ops, void *drv, struct snd_midi_channel *chan,
    struct snd_midi_channel_set *chset)
{
	int type;
	int val;

	if (chset->midi_mode != SNDRV_MIDI_MODE_NONE) {
		type = (chan->control[MIDI_CTL_REGIST_PARM_NUM_MSB] << 8) |
			chan->control[MIDI_CTL_REGIST_PARM_NUM_LSB];
		val = (chan->control[MIDI_CTL_MSB_DATA_ENTRY] << 7) |
			chan->control[MIDI_CTL_LSB_DATA_ENTRY];

		switch (type) {
		case 0x0000: /* Pitch bend sensitivity */
			/* MSB only / 1 semitone per 128 */
			chan->gm_rpn_pitch_bend_range = val;
			break;
					
		case 0x0001: /* fine tuning: */
			/* MSB/LSB, 8192=center, 100/8192 cent step */
			chan->gm_rpn_fine_tuning = val - 8192;
			break;

		case 0x0002: /* coarse tuning */
			/* MSB only / 8192=center, 1 semitone per 128 */
			chan->gm_rpn_coarse_tuning = val - 8192;
			break;

		case 0x7F7F: /* "lock-in" RPN */
			/* ignored */
			break;
		}
	}
	/* should call nrpn or rpn callback here.. */
}

/*
 * Process an nrpn message.
 */
static void
nrpn(struct snd_midi_op *ops, void *drv, struct snd_midi_channel *chan,
     struct snd_midi_channel_set *chset)
{
	/* parse XG NRPNs here if possible */
	if (ops->nrpn)
		ops->nrpn(drv, chan, chset);
}


/*
 * convert channel parameter in GS sysex
 */
static int
get_channel(unsigned char cmd)
{
	int p = cmd & 0x0f;
	if (p == 0)
		p = 9;
	else if (p < 10)
		p--;
	return p;
}


/*
 * Process a sysex message.
 */
static void
sysex(struct snd_midi_op *ops, void *private, unsigned char *buf, int len,
      struct snd_midi_channel_set *chset)
{
	/* GM on */
	static unsigned char gm_on_macro[] = {
		0x7e,0x7f,0x09,0x01,
	};
	/* XG on */
	static unsigned char xg_on_macro[] = {
		0x43,0x10,0x4c,0x00,0x00,0x7e,0x00,
	};
	/* GS prefix
	 * drum channel: XX=0x1?(channel), YY=0x15, ZZ=on/off
	 * reverb mode: XX=0x01, YY=0x30, ZZ=0-7
	 * chorus mode: XX=0x01, YY=0x38, ZZ=0-7
	 * master vol:  XX=0x00, YY=0x04, ZZ=0-127
	 */
	static unsigned char gs_pfx_macro[] = {
		0x41,0x10,0x42,0x12,0x40,/*XX,YY,ZZ*/
	};

	int parsed = SNDRV_MIDI_SYSEX_NOT_PARSED;

	if (len <= 0 || buf[0] != 0xf0)
		return;
	/* skip first byte */
	buf++;
	len--;

	/* GM on */
	if (len >= (int)sizeof(gm_on_macro) &&
	    memcmp(buf, gm_on_macro, sizeof(gm_on_macro)) == 0) {
		if (chset->midi_mode != SNDRV_MIDI_MODE_GS &&
		    chset->midi_mode != SNDRV_MIDI_MODE_XG) {
			chset->midi_mode = SNDRV_MIDI_MODE_GM;
			reset_all_channels(chset);
			parsed = SNDRV_MIDI_SYSEX_GM_ON;
		}
	}

	/* GS macros */
	else if (len >= 8 &&
		 memcmp(buf, gs_pfx_macro, sizeof(gs_pfx_macro)) == 0) {
		if (chset->midi_mode != SNDRV_MIDI_MODE_GS &&
		    chset->midi_mode != SNDRV_MIDI_MODE_XG)
			chset->midi_mode = SNDRV_MIDI_MODE_GS;

		if (buf[5] == 0x00 && buf[6] == 0x7f && buf[7] == 0x00) {
			/* GS reset */
			parsed = SNDRV_MIDI_SYSEX_GS_RESET;
			reset_all_channels(chset);
		}

		else if ((buf[5] & 0xf0) == 0x10 && buf[6] == 0x15) {
			/* drum pattern */
			int p = get_channel(buf[5]);
			if (p < chset->max_channels) {
				parsed = SNDRV_MIDI_SYSEX_GS_DRUM_CHANNEL;
				if (buf[7])
					chset->channels[p].drum_channel = 1;
				else
					chset->channels[p].drum_channel = 0;
			}

		} else if ((buf[5] & 0xf0) == 0x10 && buf[6] == 0x21) {
			/* program */
			int p = get_channel(buf[5]);
			if (p < chset->max_channels &&
			    ! chset->channels[p].drum_channel) {
				parsed = SNDRV_MIDI_SYSEX_GS_DRUM_CHANNEL;
				chset->channels[p].midi_program = buf[7];
			}

		} else if (buf[5] == 0x01 && buf[6] == 0x30) {
			/* reverb mode */
			parsed = SNDRV_MIDI_SYSEX_GS_REVERB_MODE;
			chset->gs_reverb_mode = buf[7];

		} else if (buf[5] == 0x01 && buf[6] == 0x38) {
			/* chorus mode */
			parsed = SNDRV_MIDI_SYSEX_GS_CHORUS_MODE;
			chset->gs_chorus_mode = buf[7];

		} else if (buf[5] == 0x00 && buf[6] == 0x04) {
			/* master volume */
			parsed = SNDRV_MIDI_SYSEX_GS_MASTER_VOLUME;
			chset->gs_master_volume = buf[7];

		}
	}

	/* XG on */
	else if (len >= (int)sizeof(xg_on_macro) &&
		 memcmp(buf, xg_on_macro, sizeof(xg_on_macro)) == 0) {
		int i;
		chset->midi_mode = SNDRV_MIDI_MODE_XG;
		parsed = SNDRV_MIDI_SYSEX_XG_ON;
		/* reset CC#0 for drums */
		for (i = 0; i < chset->max_channels; i++) {
			if (chset->channels[i].drum_channel)
				chset->channels[i].control[MIDI_CTL_MSB_BANK] = 127;
			else
				chset->channels[i].control[MIDI_CTL_MSB_BANK] = 0;
		}
	}

	if (ops->sysex)
		ops->sysex(private, buf - 1, len + 1, parsed, chset);
}

/*
 * all sound off
 */
static void
all_sounds_off(struct snd_midi_op *ops, void *drv, struct snd_midi_channel *chan)
{
	int n;

	if (! ops->note_terminate)
		return;
	for (n = 0; n < 128; n++) {
		if (chan->note[n]) {
			ops->note_terminate(drv, n, chan);
			chan->note[n] = 0;
		}
	}
}

/*
 * all notes off
 */
static void
all_notes_off(struct snd_midi_op *ops, void *drv, struct snd_midi_channel *chan)
{
	int n;

	if (! ops->note_off)
		return;
	for (n = 0; n < 128; n++) {
		if (chan->note[n] == SNDRV_MIDI_NOTE_ON)
			note_off(ops, drv, chan, n, 0);
	}
}

/*
 * Initialise a single midi channel control block.
 */
static void snd_midi_channel_init(struct snd_midi_channel *p, int n)
{
	if (p == NULL)
		return;

	memset(p, 0, sizeof(struct snd_midi_channel));
	p->private = NULL;
	p->number = n;

	snd_midi_reset_controllers(p);
	p->gm_rpn_pitch_bend_range = 256; /* 2 semitones */
	p->gm_rpn_fine_tuning = 0;
	p->gm_rpn_coarse_tuning = 0;

	if (n == 9)
		p->drum_channel = 1;	/* Default ch 10 as drums */
}

/*
 * Allocate and initialise a set of midi channel control blocks.
 */
static struct snd_midi_channel *snd_midi_channel_init_set(int n)
{
	struct snd_midi_channel *chan;
	int  i;

	chan = kmalloc(n * sizeof(struct snd_midi_channel), GFP_KERNEL);
	if (chan) {
		for (i = 0; i < n; i++)
			snd_midi_channel_init(chan+i, i);
	}

	return chan;
}

/*
 * reset all midi channels
 */
static void
reset_all_channels(struct snd_midi_channel_set *chset)
{
	int ch;
	for (ch = 0; ch < chset->max_channels; ch++) {
		struct snd_midi_channel *chan = chset->channels + ch;
		snd_midi_reset_controllers(chan);
		chan->gm_rpn_pitch_bend_range = 256; /* 2 semitones */
		chan->gm_rpn_fine_tuning = 0;
		chan->gm_rpn_coarse_tuning = 0;

		if (ch == 9)
			chan->drum_channel = 1;
		else
			chan->drum_channel = 0;
	}
}


/*
 * Allocate and initialise a midi channel set.
 */
struct snd_midi_channel_set *snd_midi_channel_alloc_set(int n)
{
	struct snd_midi_channel_set *chset;

	chset = kmalloc(sizeof(*chset), GFP_KERNEL);
	if (chset) {
		chset->channels = snd_midi_channel_init_set(n);
		chset->private_data = NULL;
		chset->max_channels = n;
	}
	return chset;
}

/*
 * Reset the midi controllers on a particular channel to default values.
 */
static void snd_midi_reset_controllers(struct snd_midi_channel *chan)
{
	memset(chan->control, 0, sizeof(chan->control));
	chan->gm_volume = 127;
	chan->gm_expression = 127;
	chan->gm_pan = 64;
}


/*
 * Free a midi channel set.
 */
void snd_midi_channel_free_set(struct snd_midi_channel_set *chset)
{
	if (chset == NULL)
		return;
	kfree(chset->channels);
	kfree(chset);
}

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

static void __exit alsa_seq_midi_emul_exit(void)
{
}

module_init(alsa_seq_midi_emul_init)
module_exit(alsa_seq_midi_emul_exit)

EXPORT_SYMBOL(snd_midi_process_event);
EXPORT_SYMBOL(snd_midi_channel_set_clear);
EXPORT_SYMBOL(snd_midi_channel_alloc_set);
EXPORT_SYMBOL(snd_midi_channel_free_set);