xref: /openbmc/linux/sound/core/seq/seq_midi_emul.c (revision eb3fcf00)
1 /*
2  *  GM/GS/XG midi module.
3  *
4  *  Copyright (C) 1999 Steve Ratcliffe
5  *
6  *  Based on awe_wave.c by Takashi Iwai
7  *
8  *   This program is free software; you can redistribute it and/or modify
9  *   it under the terms of the GNU General Public License as published by
10  *   the Free Software Foundation; either version 2 of the License, or
11  *   (at your option) any later version.
12  *
13  *   This program is distributed in the hope that it will be useful,
14  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
15  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  *   GNU General Public License for more details.
17  *
18  *   You should have received a copy of the GNU General Public License
19  *   along with this program; if not, write to the Free Software
20  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
21  *
22  */
23 /*
24  * This module is used to keep track of the current midi state.
25  * It can be used for drivers that are required to emulate midi when
26  * the hardware doesn't.
27  *
28  * It was written for a AWE64 driver, but there should be no AWE specific
29  * code in here.  If there is it should be reported as a bug.
30  */
31 
32 #include <linux/init.h>
33 #include <linux/slab.h>
34 #include <linux/string.h>
35 #include <linux/module.h>
36 #include <sound/core.h>
37 #include <sound/seq_kernel.h>
38 #include <sound/seq_midi_emul.h>
39 #include <sound/initval.h>
40 #include <sound/asoundef.h>
41 
42 MODULE_AUTHOR("Takashi Iwai / Steve Ratcliffe");
43 MODULE_DESCRIPTION("Advanced Linux Sound Architecture sequencer MIDI emulation.");
44 MODULE_LICENSE("GPL");
45 
46 /* Prototypes for static functions */
47 static void note_off(struct snd_midi_op *ops, void *drv,
48 		     struct snd_midi_channel *chan,
49 		     int note, int vel);
50 static void do_control(struct snd_midi_op *ops, void *private,
51 		       struct snd_midi_channel_set *chset,
52 		       struct snd_midi_channel *chan,
53 		       int control, int value);
54 static void rpn(struct snd_midi_op *ops, void *drv, struct snd_midi_channel *chan,
55 		struct snd_midi_channel_set *chset);
56 static void nrpn(struct snd_midi_op *ops, void *drv, struct snd_midi_channel *chan,
57 		 struct snd_midi_channel_set *chset);
58 static void sysex(struct snd_midi_op *ops, void *private, unsigned char *sysex,
59 		  int len, struct snd_midi_channel_set *chset);
60 static void all_sounds_off(struct snd_midi_op *ops, void *private,
61 			   struct snd_midi_channel *chan);
62 static void all_notes_off(struct snd_midi_op *ops, void *private,
63 			  struct snd_midi_channel *chan);
64 static void snd_midi_reset_controllers(struct snd_midi_channel *chan);
65 static void reset_all_channels(struct snd_midi_channel_set *chset);
66 
67 
68 /*
69  * Process an event in a driver independent way.  This means dealing
70  * with RPN, NRPN, SysEx etc that are defined for common midi applications
71  * such as GM, GS and XG.
72  * There modes that this module will run in are:
73  *   Generic MIDI - no interpretation at all, it will just save current values
74  *                  of controllers etc.
75  *   GM - You can use all gm_ prefixed elements of chan.  Controls, RPN, NRPN,
76  *        SysEx will be interpreded as defined in General Midi.
77  *   GS - You can use all gs_ prefixed elements of chan. Codes for GS will be
78  *        interpreted.
79  *   XG - You can use all xg_ prefixed elements of chan.  Codes for XG will
80  *        be interpreted.
81  */
82 void
83 snd_midi_process_event(struct snd_midi_op *ops,
84 		       struct snd_seq_event *ev,
85 		       struct snd_midi_channel_set *chanset)
86 {
87 	struct snd_midi_channel *chan;
88 	void *drv;
89 	int dest_channel = 0;
90 
91 	if (ev == NULL || chanset == NULL) {
92 		pr_debug("ALSA: seq_midi_emul: ev or chanbase NULL (snd_midi_process_event)\n");
93 		return;
94 	}
95 	if (chanset->channels == NULL)
96 		return;
97 
98 	if (snd_seq_ev_is_channel_type(ev)) {
99 		dest_channel = ev->data.note.channel;
100 		if (dest_channel >= chanset->max_channels) {
101 			pr_debug("ALSA: seq_midi_emul: dest channel is %d, max is %d\n",
102 				   dest_channel, chanset->max_channels);
103 			return;
104 		}
105 	}
106 
107 	chan = chanset->channels + dest_channel;
108 	drv  = chanset->private_data;
109 
110 	/* EVENT_NOTE should be processed before queued */
111 	if (ev->type == SNDRV_SEQ_EVENT_NOTE)
112 		return;
113 
114 	/* Make sure that we don't have a note on that should really be
115 	 * a note off */
116 	if (ev->type == SNDRV_SEQ_EVENT_NOTEON && ev->data.note.velocity == 0)
117 		ev->type = SNDRV_SEQ_EVENT_NOTEOFF;
118 
119 	/* Make sure the note is within array range */
120 	if (ev->type == SNDRV_SEQ_EVENT_NOTEON ||
121 	    ev->type == SNDRV_SEQ_EVENT_NOTEOFF ||
122 	    ev->type == SNDRV_SEQ_EVENT_KEYPRESS) {
123 		if (ev->data.note.note >= 128)
124 			return;
125 	}
126 
127 	switch (ev->type) {
128 	case SNDRV_SEQ_EVENT_NOTEON:
129 		if (chan->note[ev->data.note.note] & SNDRV_MIDI_NOTE_ON) {
130 			if (ops->note_off)
131 				ops->note_off(drv, ev->data.note.note, 0, chan);
132 		}
133 		chan->note[ev->data.note.note] = SNDRV_MIDI_NOTE_ON;
134 		if (ops->note_on)
135 			ops->note_on(drv, ev->data.note.note, ev->data.note.velocity, chan);
136 		break;
137 	case SNDRV_SEQ_EVENT_NOTEOFF:
138 		if (! (chan->note[ev->data.note.note] & SNDRV_MIDI_NOTE_ON))
139 			break;
140 		if (ops->note_off)
141 			note_off(ops, drv, chan, ev->data.note.note, ev->data.note.velocity);
142 		break;
143 	case SNDRV_SEQ_EVENT_KEYPRESS:
144 		if (ops->key_press)
145 			ops->key_press(drv, ev->data.note.note, ev->data.note.velocity, chan);
146 		break;
147 	case SNDRV_SEQ_EVENT_CONTROLLER:
148 		do_control(ops, drv, chanset, chan,
149 			   ev->data.control.param, ev->data.control.value);
150 		break;
151 	case SNDRV_SEQ_EVENT_PGMCHANGE:
152 		chan->midi_program = ev->data.control.value;
153 		break;
154 	case SNDRV_SEQ_EVENT_PITCHBEND:
155 		chan->midi_pitchbend = ev->data.control.value;
156 		if (ops->control)
157 			ops->control(drv, MIDI_CTL_PITCHBEND, chan);
158 		break;
159 	case SNDRV_SEQ_EVENT_CHANPRESS:
160 		chan->midi_pressure = ev->data.control.value;
161 		if (ops->control)
162 			ops->control(drv, MIDI_CTL_CHAN_PRESSURE, chan);
163 		break;
164 	case SNDRV_SEQ_EVENT_CONTROL14:
165 		/* Best guess is that this is any of the 14 bit controller values */
166 		if (ev->data.control.param < 32) {
167 			/* set low part first */
168 			chan->control[ev->data.control.param + 32] =
169 				ev->data.control.value & 0x7f;
170 			do_control(ops, drv, chanset, chan,
171 				   ev->data.control.param,
172 				   ((ev->data.control.value>>7) & 0x7f));
173 		} else
174 			do_control(ops, drv, chanset, chan,
175 				   ev->data.control.param,
176 				   ev->data.control.value);
177 		break;
178 	case SNDRV_SEQ_EVENT_NONREGPARAM:
179 		/* Break it back into its controller values */
180 		chan->param_type = SNDRV_MIDI_PARAM_TYPE_NONREGISTERED;
181 		chan->control[MIDI_CTL_MSB_DATA_ENTRY]
182 			= (ev->data.control.value >> 7) & 0x7f;
183 		chan->control[MIDI_CTL_LSB_DATA_ENTRY]
184 			= ev->data.control.value & 0x7f;
185 		chan->control[MIDI_CTL_NONREG_PARM_NUM_MSB]
186 			= (ev->data.control.param >> 7) & 0x7f;
187 		chan->control[MIDI_CTL_NONREG_PARM_NUM_LSB]
188 			= ev->data.control.param & 0x7f;
189 		nrpn(ops, drv, chan, chanset);
190 		break;
191 	case SNDRV_SEQ_EVENT_REGPARAM:
192 		/* Break it back into its controller values */
193 		chan->param_type = SNDRV_MIDI_PARAM_TYPE_REGISTERED;
194 		chan->control[MIDI_CTL_MSB_DATA_ENTRY]
195 			= (ev->data.control.value >> 7) & 0x7f;
196 		chan->control[MIDI_CTL_LSB_DATA_ENTRY]
197 			= ev->data.control.value & 0x7f;
198 		chan->control[MIDI_CTL_REGIST_PARM_NUM_MSB]
199 			= (ev->data.control.param >> 7) & 0x7f;
200 		chan->control[MIDI_CTL_REGIST_PARM_NUM_LSB]
201 			= ev->data.control.param & 0x7f;
202 		rpn(ops, drv, chan, chanset);
203 		break;
204 	case SNDRV_SEQ_EVENT_SYSEX:
205 		if ((ev->flags & SNDRV_SEQ_EVENT_LENGTH_MASK) == SNDRV_SEQ_EVENT_LENGTH_VARIABLE) {
206 			unsigned char sysexbuf[64];
207 			int len;
208 			len = snd_seq_expand_var_event(ev, sizeof(sysexbuf), sysexbuf, 1, 0);
209 			if (len > 0)
210 				sysex(ops, drv, sysexbuf, len, chanset);
211 		}
212 		break;
213 	case SNDRV_SEQ_EVENT_SONGPOS:
214 	case SNDRV_SEQ_EVENT_SONGSEL:
215 	case SNDRV_SEQ_EVENT_CLOCK:
216 	case SNDRV_SEQ_EVENT_START:
217 	case SNDRV_SEQ_EVENT_CONTINUE:
218 	case SNDRV_SEQ_EVENT_STOP:
219 	case SNDRV_SEQ_EVENT_QFRAME:
220 	case SNDRV_SEQ_EVENT_TEMPO:
221 	case SNDRV_SEQ_EVENT_TIMESIGN:
222 	case SNDRV_SEQ_EVENT_KEYSIGN:
223 		goto not_yet;
224 	case SNDRV_SEQ_EVENT_SENSING:
225 		break;
226 	case SNDRV_SEQ_EVENT_CLIENT_START:
227 	case SNDRV_SEQ_EVENT_CLIENT_EXIT:
228 	case SNDRV_SEQ_EVENT_CLIENT_CHANGE:
229 	case SNDRV_SEQ_EVENT_PORT_START:
230 	case SNDRV_SEQ_EVENT_PORT_EXIT:
231 	case SNDRV_SEQ_EVENT_PORT_CHANGE:
232 	case SNDRV_SEQ_EVENT_ECHO:
233 	not_yet:
234 	default:
235 		/*pr_debug("ALSA: seq_midi_emul: Unimplemented event %d\n", ev->type);*/
236 		break;
237 	}
238 }
239 
240 
241 /*
242  * release note
243  */
244 static void
245 note_off(struct snd_midi_op *ops, void *drv, struct snd_midi_channel *chan,
246 	 int note, int vel)
247 {
248 	if (chan->gm_hold) {
249 		/* Hold this note until pedal is turned off */
250 		chan->note[note] |= SNDRV_MIDI_NOTE_RELEASED;
251 	} else if (chan->note[note] & SNDRV_MIDI_NOTE_SOSTENUTO) {
252 		/* Mark this note as release; it will be turned off when sostenuto
253 		 * is turned off */
254 		chan->note[note] |= SNDRV_MIDI_NOTE_RELEASED;
255 	} else {
256 		chan->note[note] = 0;
257 		if (ops->note_off)
258 			ops->note_off(drv, note, vel, chan);
259 	}
260 }
261 
262 /*
263  * Do all driver independent operations for this controller and pass
264  * events that need to take place immediately to the driver.
265  */
266 static void
267 do_control(struct snd_midi_op *ops, void *drv, struct snd_midi_channel_set *chset,
268 	   struct snd_midi_channel *chan, int control, int value)
269 {
270 	int  i;
271 
272 	if (control >= ARRAY_SIZE(chan->control))
273 		return;
274 
275 	/* Switches */
276 	if ((control >=64 && control <=69) || (control >= 80 && control <= 83)) {
277 		/* These are all switches; either off or on so set to 0 or 127 */
278 		value = (value >= 64)? 127: 0;
279 	}
280 	chan->control[control] = value;
281 
282 	switch (control) {
283 	case MIDI_CTL_SUSTAIN:
284 		if (value == 0) {
285 			/* Sustain has been released, turn off held notes */
286 			for (i = 0; i < 128; i++) {
287 				if (chan->note[i] & SNDRV_MIDI_NOTE_RELEASED) {
288 					chan->note[i] = SNDRV_MIDI_NOTE_OFF;
289 					if (ops->note_off)
290 						ops->note_off(drv, i, 0, chan);
291 				}
292 			}
293 		}
294 		break;
295 	case MIDI_CTL_PORTAMENTO:
296 		break;
297 	case MIDI_CTL_SOSTENUTO:
298 		if (value) {
299 			/* Mark each note that is currently held down */
300 			for (i = 0; i < 128; i++) {
301 				if (chan->note[i] & SNDRV_MIDI_NOTE_ON)
302 					chan->note[i] |= SNDRV_MIDI_NOTE_SOSTENUTO;
303 			}
304 		} else {
305 			/* release all notes that were held */
306 			for (i = 0; i < 128; i++) {
307 				if (chan->note[i] & SNDRV_MIDI_NOTE_SOSTENUTO) {
308 					chan->note[i] &= ~SNDRV_MIDI_NOTE_SOSTENUTO;
309 					if (chan->note[i] & SNDRV_MIDI_NOTE_RELEASED) {
310 						chan->note[i] = SNDRV_MIDI_NOTE_OFF;
311 						if (ops->note_off)
312 							ops->note_off(drv, i, 0, chan);
313 					}
314 				}
315 			}
316 		}
317 		break;
318 	case MIDI_CTL_MSB_DATA_ENTRY:
319 		chan->control[MIDI_CTL_LSB_DATA_ENTRY] = 0;
320 		/* go through here */
321 	case MIDI_CTL_LSB_DATA_ENTRY:
322 		if (chan->param_type == SNDRV_MIDI_PARAM_TYPE_REGISTERED)
323 			rpn(ops, drv, chan, chset);
324 		else
325 			nrpn(ops, drv, chan, chset);
326 		break;
327 	case MIDI_CTL_REGIST_PARM_NUM_LSB:
328 	case MIDI_CTL_REGIST_PARM_NUM_MSB:
329 		chan->param_type = SNDRV_MIDI_PARAM_TYPE_REGISTERED;
330 		break;
331 	case MIDI_CTL_NONREG_PARM_NUM_LSB:
332 	case MIDI_CTL_NONREG_PARM_NUM_MSB:
333 		chan->param_type = SNDRV_MIDI_PARAM_TYPE_NONREGISTERED;
334 		break;
335 
336 	case MIDI_CTL_ALL_SOUNDS_OFF:
337 		all_sounds_off(ops, drv, chan);
338 		break;
339 
340 	case MIDI_CTL_ALL_NOTES_OFF:
341 		all_notes_off(ops, drv, chan);
342 		break;
343 
344 	case MIDI_CTL_MSB_BANK:
345 		if (chset->midi_mode == SNDRV_MIDI_MODE_XG) {
346 			if (value == 127)
347 				chan->drum_channel = 1;
348 			else
349 				chan->drum_channel = 0;
350 		}
351 		break;
352 	case MIDI_CTL_LSB_BANK:
353 		break;
354 
355 	case MIDI_CTL_RESET_CONTROLLERS:
356 		snd_midi_reset_controllers(chan);
357 		break;
358 
359 	case MIDI_CTL_SOFT_PEDAL:
360 	case MIDI_CTL_LEGATO_FOOTSWITCH:
361 	case MIDI_CTL_HOLD2:
362 	case MIDI_CTL_SC1_SOUND_VARIATION:
363 	case MIDI_CTL_SC2_TIMBRE:
364 	case MIDI_CTL_SC3_RELEASE_TIME:
365 	case MIDI_CTL_SC4_ATTACK_TIME:
366 	case MIDI_CTL_SC5_BRIGHTNESS:
367 	case MIDI_CTL_E1_REVERB_DEPTH:
368 	case MIDI_CTL_E2_TREMOLO_DEPTH:
369 	case MIDI_CTL_E3_CHORUS_DEPTH:
370 	case MIDI_CTL_E4_DETUNE_DEPTH:
371 	case MIDI_CTL_E5_PHASER_DEPTH:
372 		goto notyet;
373 	notyet:
374 	default:
375 		if (ops->control)
376 			ops->control(drv, control, chan);
377 		break;
378 	}
379 }
380 
381 
382 /*
383  * initialize the MIDI status
384  */
385 void
386 snd_midi_channel_set_clear(struct snd_midi_channel_set *chset)
387 {
388 	int i;
389 
390 	chset->midi_mode = SNDRV_MIDI_MODE_GM;
391 	chset->gs_master_volume = 127;
392 
393 	for (i = 0; i < chset->max_channels; i++) {
394 		struct snd_midi_channel *chan = chset->channels + i;
395 		memset(chan->note, 0, sizeof(chan->note));
396 
397 		chan->midi_aftertouch = 0;
398 		chan->midi_pressure = 0;
399 		chan->midi_program = 0;
400 		chan->midi_pitchbend = 0;
401 		snd_midi_reset_controllers(chan);
402 		chan->gm_rpn_pitch_bend_range = 256; /* 2 semitones */
403 		chan->gm_rpn_fine_tuning = 0;
404 		chan->gm_rpn_coarse_tuning = 0;
405 
406 		if (i == 9)
407 			chan->drum_channel = 1;
408 		else
409 			chan->drum_channel = 0;
410 	}
411 }
412 
413 /*
414  * Process a rpn message.
415  */
416 static void
417 rpn(struct snd_midi_op *ops, void *drv, struct snd_midi_channel *chan,
418     struct snd_midi_channel_set *chset)
419 {
420 	int type;
421 	int val;
422 
423 	if (chset->midi_mode != SNDRV_MIDI_MODE_NONE) {
424 		type = (chan->control[MIDI_CTL_REGIST_PARM_NUM_MSB] << 8) |
425 			chan->control[MIDI_CTL_REGIST_PARM_NUM_LSB];
426 		val = (chan->control[MIDI_CTL_MSB_DATA_ENTRY] << 7) |
427 			chan->control[MIDI_CTL_LSB_DATA_ENTRY];
428 
429 		switch (type) {
430 		case 0x0000: /* Pitch bend sensitivity */
431 			/* MSB only / 1 semitone per 128 */
432 			chan->gm_rpn_pitch_bend_range = val;
433 			break;
434 
435 		case 0x0001: /* fine tuning: */
436 			/* MSB/LSB, 8192=center, 100/8192 cent step */
437 			chan->gm_rpn_fine_tuning = val - 8192;
438 			break;
439 
440 		case 0x0002: /* coarse tuning */
441 			/* MSB only / 8192=center, 1 semitone per 128 */
442 			chan->gm_rpn_coarse_tuning = val - 8192;
443 			break;
444 
445 		case 0x7F7F: /* "lock-in" RPN */
446 			/* ignored */
447 			break;
448 		}
449 	}
450 	/* should call nrpn or rpn callback here.. */
451 }
452 
453 /*
454  * Process an nrpn message.
455  */
456 static void
457 nrpn(struct snd_midi_op *ops, void *drv, struct snd_midi_channel *chan,
458      struct snd_midi_channel_set *chset)
459 {
460 	/* parse XG NRPNs here if possible */
461 	if (ops->nrpn)
462 		ops->nrpn(drv, chan, chset);
463 }
464 
465 
466 /*
467  * convert channel parameter in GS sysex
468  */
469 static int
470 get_channel(unsigned char cmd)
471 {
472 	int p = cmd & 0x0f;
473 	if (p == 0)
474 		p = 9;
475 	else if (p < 10)
476 		p--;
477 	return p;
478 }
479 
480 
481 /*
482  * Process a sysex message.
483  */
484 static void
485 sysex(struct snd_midi_op *ops, void *private, unsigned char *buf, int len,
486       struct snd_midi_channel_set *chset)
487 {
488 	/* GM on */
489 	static unsigned char gm_on_macro[] = {
490 		0x7e,0x7f,0x09,0x01,
491 	};
492 	/* XG on */
493 	static unsigned char xg_on_macro[] = {
494 		0x43,0x10,0x4c,0x00,0x00,0x7e,0x00,
495 	};
496 	/* GS prefix
497 	 * drum channel: XX=0x1?(channel), YY=0x15, ZZ=on/off
498 	 * reverb mode: XX=0x01, YY=0x30, ZZ=0-7
499 	 * chorus mode: XX=0x01, YY=0x38, ZZ=0-7
500 	 * master vol:  XX=0x00, YY=0x04, ZZ=0-127
501 	 */
502 	static unsigned char gs_pfx_macro[] = {
503 		0x41,0x10,0x42,0x12,0x40,/*XX,YY,ZZ*/
504 	};
505 
506 	int parsed = SNDRV_MIDI_SYSEX_NOT_PARSED;
507 
508 	if (len <= 0 || buf[0] != 0xf0)
509 		return;
510 	/* skip first byte */
511 	buf++;
512 	len--;
513 
514 	/* GM on */
515 	if (len >= (int)sizeof(gm_on_macro) &&
516 	    memcmp(buf, gm_on_macro, sizeof(gm_on_macro)) == 0) {
517 		if (chset->midi_mode != SNDRV_MIDI_MODE_GS &&
518 		    chset->midi_mode != SNDRV_MIDI_MODE_XG) {
519 			chset->midi_mode = SNDRV_MIDI_MODE_GM;
520 			reset_all_channels(chset);
521 			parsed = SNDRV_MIDI_SYSEX_GM_ON;
522 		}
523 	}
524 
525 	/* GS macros */
526 	else if (len >= 8 &&
527 		 memcmp(buf, gs_pfx_macro, sizeof(gs_pfx_macro)) == 0) {
528 		if (chset->midi_mode != SNDRV_MIDI_MODE_GS &&
529 		    chset->midi_mode != SNDRV_MIDI_MODE_XG)
530 			chset->midi_mode = SNDRV_MIDI_MODE_GS;
531 
532 		if (buf[5] == 0x00 && buf[6] == 0x7f && buf[7] == 0x00) {
533 			/* GS reset */
534 			parsed = SNDRV_MIDI_SYSEX_GS_RESET;
535 			reset_all_channels(chset);
536 		}
537 
538 		else if ((buf[5] & 0xf0) == 0x10 && buf[6] == 0x15) {
539 			/* drum pattern */
540 			int p = get_channel(buf[5]);
541 			if (p < chset->max_channels) {
542 				parsed = SNDRV_MIDI_SYSEX_GS_DRUM_CHANNEL;
543 				if (buf[7])
544 					chset->channels[p].drum_channel = 1;
545 				else
546 					chset->channels[p].drum_channel = 0;
547 			}
548 
549 		} else if ((buf[5] & 0xf0) == 0x10 && buf[6] == 0x21) {
550 			/* program */
551 			int p = get_channel(buf[5]);
552 			if (p < chset->max_channels &&
553 			    ! chset->channels[p].drum_channel) {
554 				parsed = SNDRV_MIDI_SYSEX_GS_DRUM_CHANNEL;
555 				chset->channels[p].midi_program = buf[7];
556 			}
557 
558 		} else if (buf[5] == 0x01 && buf[6] == 0x30) {
559 			/* reverb mode */
560 			parsed = SNDRV_MIDI_SYSEX_GS_REVERB_MODE;
561 			chset->gs_reverb_mode = buf[7];
562 
563 		} else if (buf[5] == 0x01 && buf[6] == 0x38) {
564 			/* chorus mode */
565 			parsed = SNDRV_MIDI_SYSEX_GS_CHORUS_MODE;
566 			chset->gs_chorus_mode = buf[7];
567 
568 		} else if (buf[5] == 0x00 && buf[6] == 0x04) {
569 			/* master volume */
570 			parsed = SNDRV_MIDI_SYSEX_GS_MASTER_VOLUME;
571 			chset->gs_master_volume = buf[7];
572 
573 		}
574 	}
575 
576 	/* XG on */
577 	else if (len >= (int)sizeof(xg_on_macro) &&
578 		 memcmp(buf, xg_on_macro, sizeof(xg_on_macro)) == 0) {
579 		int i;
580 		chset->midi_mode = SNDRV_MIDI_MODE_XG;
581 		parsed = SNDRV_MIDI_SYSEX_XG_ON;
582 		/* reset CC#0 for drums */
583 		for (i = 0; i < chset->max_channels; i++) {
584 			if (chset->channels[i].drum_channel)
585 				chset->channels[i].control[MIDI_CTL_MSB_BANK] = 127;
586 			else
587 				chset->channels[i].control[MIDI_CTL_MSB_BANK] = 0;
588 		}
589 	}
590 
591 	if (ops->sysex)
592 		ops->sysex(private, buf - 1, len + 1, parsed, chset);
593 }
594 
595 /*
596  * all sound off
597  */
598 static void
599 all_sounds_off(struct snd_midi_op *ops, void *drv, struct snd_midi_channel *chan)
600 {
601 	int n;
602 
603 	if (! ops->note_terminate)
604 		return;
605 	for (n = 0; n < 128; n++) {
606 		if (chan->note[n]) {
607 			ops->note_terminate(drv, n, chan);
608 			chan->note[n] = 0;
609 		}
610 	}
611 }
612 
613 /*
614  * all notes off
615  */
616 static void
617 all_notes_off(struct snd_midi_op *ops, void *drv, struct snd_midi_channel *chan)
618 {
619 	int n;
620 
621 	if (! ops->note_off)
622 		return;
623 	for (n = 0; n < 128; n++) {
624 		if (chan->note[n] == SNDRV_MIDI_NOTE_ON)
625 			note_off(ops, drv, chan, n, 0);
626 	}
627 }
628 
629 /*
630  * Initialise a single midi channel control block.
631  */
632 static void snd_midi_channel_init(struct snd_midi_channel *p, int n)
633 {
634 	if (p == NULL)
635 		return;
636 
637 	memset(p, 0, sizeof(struct snd_midi_channel));
638 	p->private = NULL;
639 	p->number = n;
640 
641 	snd_midi_reset_controllers(p);
642 	p->gm_rpn_pitch_bend_range = 256; /* 2 semitones */
643 	p->gm_rpn_fine_tuning = 0;
644 	p->gm_rpn_coarse_tuning = 0;
645 
646 	if (n == 9)
647 		p->drum_channel = 1;	/* Default ch 10 as drums */
648 }
649 
650 /*
651  * Allocate and initialise a set of midi channel control blocks.
652  */
653 static struct snd_midi_channel *snd_midi_channel_init_set(int n)
654 {
655 	struct snd_midi_channel *chan;
656 	int  i;
657 
658 	chan = kmalloc(n * sizeof(struct snd_midi_channel), GFP_KERNEL);
659 	if (chan) {
660 		for (i = 0; i < n; i++)
661 			snd_midi_channel_init(chan+i, i);
662 	}
663 
664 	return chan;
665 }
666 
667 /*
668  * reset all midi channels
669  */
670 static void
671 reset_all_channels(struct snd_midi_channel_set *chset)
672 {
673 	int ch;
674 	for (ch = 0; ch < chset->max_channels; ch++) {
675 		struct snd_midi_channel *chan = chset->channels + ch;
676 		snd_midi_reset_controllers(chan);
677 		chan->gm_rpn_pitch_bend_range = 256; /* 2 semitones */
678 		chan->gm_rpn_fine_tuning = 0;
679 		chan->gm_rpn_coarse_tuning = 0;
680 
681 		if (ch == 9)
682 			chan->drum_channel = 1;
683 		else
684 			chan->drum_channel = 0;
685 	}
686 }
687 
688 
689 /*
690  * Allocate and initialise a midi channel set.
691  */
692 struct snd_midi_channel_set *snd_midi_channel_alloc_set(int n)
693 {
694 	struct snd_midi_channel_set *chset;
695 
696 	chset = kmalloc(sizeof(*chset), GFP_KERNEL);
697 	if (chset) {
698 		chset->channels = snd_midi_channel_init_set(n);
699 		chset->private_data = NULL;
700 		chset->max_channels = n;
701 	}
702 	return chset;
703 }
704 
705 /*
706  * Reset the midi controllers on a particular channel to default values.
707  */
708 static void snd_midi_reset_controllers(struct snd_midi_channel *chan)
709 {
710 	memset(chan->control, 0, sizeof(chan->control));
711 	chan->gm_volume = 127;
712 	chan->gm_expression = 127;
713 	chan->gm_pan = 64;
714 }
715 
716 
717 /*
718  * Free a midi channel set.
719  */
720 void snd_midi_channel_free_set(struct snd_midi_channel_set *chset)
721 {
722 	if (chset == NULL)
723 		return;
724 	kfree(chset->channels);
725 	kfree(chset);
726 }
727 
728 static int __init alsa_seq_midi_emul_init(void)
729 {
730 	return 0;
731 }
732 
733 static void __exit alsa_seq_midi_emul_exit(void)
734 {
735 }
736 
737 module_init(alsa_seq_midi_emul_init)
738 module_exit(alsa_seq_midi_emul_exit)
739 
740 EXPORT_SYMBOL(snd_midi_process_event);
741 EXPORT_SYMBOL(snd_midi_channel_set_clear);
742 EXPORT_SYMBOL(snd_midi_channel_alloc_set);
743 EXPORT_SYMBOL(snd_midi_channel_free_set);
744