xref: /linux/sound/core/seq/seq_midi_emul.c (revision 6fdcba32711044c35c0e1b094cbd8f3f0b4472c9)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  GM/GS/XG midi module.
4  *
5  *  Copyright (C) 1999 Steve Ratcliffe
6  *
7  *  Based on awe_wave.c by Takashi Iwai
8  */
9 /*
10  * This module is used to keep track of the current midi state.
11  * It can be used for drivers that are required to emulate midi when
12  * the hardware doesn't.
13  *
14  * It was written for a AWE64 driver, but there should be no AWE specific
15  * code in here.  If there is it should be reported as a bug.
16  */
17 
18 #include <linux/init.h>
19 #include <linux/slab.h>
20 #include <linux/string.h>
21 #include <linux/module.h>
22 #include <sound/core.h>
23 #include <sound/seq_kernel.h>
24 #include <sound/seq_midi_emul.h>
25 #include <sound/initval.h>
26 #include <sound/asoundef.h>
27 
28 MODULE_AUTHOR("Takashi Iwai / Steve Ratcliffe");
29 MODULE_DESCRIPTION("Advanced Linux Sound Architecture sequencer MIDI emulation.");
30 MODULE_LICENSE("GPL");
31 
32 /* Prototypes for static functions */
33 static void note_off(struct snd_midi_op *ops, void *drv,
34 		     struct snd_midi_channel *chan,
35 		     int note, int vel);
36 static void do_control(struct snd_midi_op *ops, void *private,
37 		       struct snd_midi_channel_set *chset,
38 		       struct snd_midi_channel *chan,
39 		       int control, int value);
40 static void rpn(struct snd_midi_op *ops, void *drv, struct snd_midi_channel *chan,
41 		struct snd_midi_channel_set *chset);
42 static void nrpn(struct snd_midi_op *ops, void *drv, struct snd_midi_channel *chan,
43 		 struct snd_midi_channel_set *chset);
44 static void sysex(struct snd_midi_op *ops, void *private, unsigned char *sysex,
45 		  int len, struct snd_midi_channel_set *chset);
46 static void all_sounds_off(struct snd_midi_op *ops, void *private,
47 			   struct snd_midi_channel *chan);
48 static void all_notes_off(struct snd_midi_op *ops, void *private,
49 			  struct snd_midi_channel *chan);
50 static void snd_midi_reset_controllers(struct snd_midi_channel *chan);
51 static void reset_all_channels(struct snd_midi_channel_set *chset);
52 
53 
54 /*
55  * Process an event in a driver independent way.  This means dealing
56  * with RPN, NRPN, SysEx etc that are defined for common midi applications
57  * such as GM, GS and XG.
58  * There modes that this module will run in are:
59  *   Generic MIDI - no interpretation at all, it will just save current values
60  *                  of controllers etc.
61  *   GM - You can use all gm_ prefixed elements of chan.  Controls, RPN, NRPN,
62  *        SysEx will be interpreded as defined in General Midi.
63  *   GS - You can use all gs_ prefixed elements of chan. Codes for GS will be
64  *        interpreted.
65  *   XG - You can use all xg_ prefixed elements of chan.  Codes for XG will
66  *        be interpreted.
67  */
68 void
69 snd_midi_process_event(struct snd_midi_op *ops,
70 		       struct snd_seq_event *ev,
71 		       struct snd_midi_channel_set *chanset)
72 {
73 	struct snd_midi_channel *chan;
74 	void *drv;
75 	int dest_channel = 0;
76 
77 	if (ev == NULL || chanset == NULL) {
78 		pr_debug("ALSA: seq_midi_emul: ev or chanbase NULL (snd_midi_process_event)\n");
79 		return;
80 	}
81 	if (chanset->channels == NULL)
82 		return;
83 
84 	if (snd_seq_ev_is_channel_type(ev)) {
85 		dest_channel = ev->data.note.channel;
86 		if (dest_channel >= chanset->max_channels) {
87 			pr_debug("ALSA: seq_midi_emul: dest channel is %d, max is %d\n",
88 				   dest_channel, chanset->max_channels);
89 			return;
90 		}
91 	}
92 
93 	chan = chanset->channels + dest_channel;
94 	drv  = chanset->private_data;
95 
96 	/* EVENT_NOTE should be processed before queued */
97 	if (ev->type == SNDRV_SEQ_EVENT_NOTE)
98 		return;
99 
100 	/* Make sure that we don't have a note on that should really be
101 	 * a note off */
102 	if (ev->type == SNDRV_SEQ_EVENT_NOTEON && ev->data.note.velocity == 0)
103 		ev->type = SNDRV_SEQ_EVENT_NOTEOFF;
104 
105 	/* Make sure the note is within array range */
106 	if (ev->type == SNDRV_SEQ_EVENT_NOTEON ||
107 	    ev->type == SNDRV_SEQ_EVENT_NOTEOFF ||
108 	    ev->type == SNDRV_SEQ_EVENT_KEYPRESS) {
109 		if (ev->data.note.note >= 128)
110 			return;
111 	}
112 
113 	switch (ev->type) {
114 	case SNDRV_SEQ_EVENT_NOTEON:
115 		if (chan->note[ev->data.note.note] & SNDRV_MIDI_NOTE_ON) {
116 			if (ops->note_off)
117 				ops->note_off(drv, ev->data.note.note, 0, chan);
118 		}
119 		chan->note[ev->data.note.note] = SNDRV_MIDI_NOTE_ON;
120 		if (ops->note_on)
121 			ops->note_on(drv, ev->data.note.note, ev->data.note.velocity, chan);
122 		break;
123 	case SNDRV_SEQ_EVENT_NOTEOFF:
124 		if (! (chan->note[ev->data.note.note] & SNDRV_MIDI_NOTE_ON))
125 			break;
126 		if (ops->note_off)
127 			note_off(ops, drv, chan, ev->data.note.note, ev->data.note.velocity);
128 		break;
129 	case SNDRV_SEQ_EVENT_KEYPRESS:
130 		if (ops->key_press)
131 			ops->key_press(drv, ev->data.note.note, ev->data.note.velocity, chan);
132 		break;
133 	case SNDRV_SEQ_EVENT_CONTROLLER:
134 		do_control(ops, drv, chanset, chan,
135 			   ev->data.control.param, ev->data.control.value);
136 		break;
137 	case SNDRV_SEQ_EVENT_PGMCHANGE:
138 		chan->midi_program = ev->data.control.value;
139 		break;
140 	case SNDRV_SEQ_EVENT_PITCHBEND:
141 		chan->midi_pitchbend = ev->data.control.value;
142 		if (ops->control)
143 			ops->control(drv, MIDI_CTL_PITCHBEND, chan);
144 		break;
145 	case SNDRV_SEQ_EVENT_CHANPRESS:
146 		chan->midi_pressure = ev->data.control.value;
147 		if (ops->control)
148 			ops->control(drv, MIDI_CTL_CHAN_PRESSURE, chan);
149 		break;
150 	case SNDRV_SEQ_EVENT_CONTROL14:
151 		/* Best guess is that this is any of the 14 bit controller values */
152 		if (ev->data.control.param < 32) {
153 			/* set low part first */
154 			chan->control[ev->data.control.param + 32] =
155 				ev->data.control.value & 0x7f;
156 			do_control(ops, drv, chanset, chan,
157 				   ev->data.control.param,
158 				   ((ev->data.control.value>>7) & 0x7f));
159 		} else
160 			do_control(ops, drv, chanset, chan,
161 				   ev->data.control.param,
162 				   ev->data.control.value);
163 		break;
164 	case SNDRV_SEQ_EVENT_NONREGPARAM:
165 		/* Break it back into its controller values */
166 		chan->param_type = SNDRV_MIDI_PARAM_TYPE_NONREGISTERED;
167 		chan->control[MIDI_CTL_MSB_DATA_ENTRY]
168 			= (ev->data.control.value >> 7) & 0x7f;
169 		chan->control[MIDI_CTL_LSB_DATA_ENTRY]
170 			= ev->data.control.value & 0x7f;
171 		chan->control[MIDI_CTL_NONREG_PARM_NUM_MSB]
172 			= (ev->data.control.param >> 7) & 0x7f;
173 		chan->control[MIDI_CTL_NONREG_PARM_NUM_LSB]
174 			= ev->data.control.param & 0x7f;
175 		nrpn(ops, drv, chan, chanset);
176 		break;
177 	case SNDRV_SEQ_EVENT_REGPARAM:
178 		/* Break it back into its controller values */
179 		chan->param_type = SNDRV_MIDI_PARAM_TYPE_REGISTERED;
180 		chan->control[MIDI_CTL_MSB_DATA_ENTRY]
181 			= (ev->data.control.value >> 7) & 0x7f;
182 		chan->control[MIDI_CTL_LSB_DATA_ENTRY]
183 			= ev->data.control.value & 0x7f;
184 		chan->control[MIDI_CTL_REGIST_PARM_NUM_MSB]
185 			= (ev->data.control.param >> 7) & 0x7f;
186 		chan->control[MIDI_CTL_REGIST_PARM_NUM_LSB]
187 			= ev->data.control.param & 0x7f;
188 		rpn(ops, drv, chan, chanset);
189 		break;
190 	case SNDRV_SEQ_EVENT_SYSEX:
191 		if ((ev->flags & SNDRV_SEQ_EVENT_LENGTH_MASK) == SNDRV_SEQ_EVENT_LENGTH_VARIABLE) {
192 			unsigned char sysexbuf[64];
193 			int len;
194 			len = snd_seq_expand_var_event(ev, sizeof(sysexbuf), sysexbuf, 1, 0);
195 			if (len > 0)
196 				sysex(ops, drv, sysexbuf, len, chanset);
197 		}
198 		break;
199 	case SNDRV_SEQ_EVENT_SONGPOS:
200 	case SNDRV_SEQ_EVENT_SONGSEL:
201 	case SNDRV_SEQ_EVENT_CLOCK:
202 	case SNDRV_SEQ_EVENT_START:
203 	case SNDRV_SEQ_EVENT_CONTINUE:
204 	case SNDRV_SEQ_EVENT_STOP:
205 	case SNDRV_SEQ_EVENT_QFRAME:
206 	case SNDRV_SEQ_EVENT_TEMPO:
207 	case SNDRV_SEQ_EVENT_TIMESIGN:
208 	case SNDRV_SEQ_EVENT_KEYSIGN:
209 		goto not_yet;
210 	case SNDRV_SEQ_EVENT_SENSING:
211 		break;
212 	case SNDRV_SEQ_EVENT_CLIENT_START:
213 	case SNDRV_SEQ_EVENT_CLIENT_EXIT:
214 	case SNDRV_SEQ_EVENT_CLIENT_CHANGE:
215 	case SNDRV_SEQ_EVENT_PORT_START:
216 	case SNDRV_SEQ_EVENT_PORT_EXIT:
217 	case SNDRV_SEQ_EVENT_PORT_CHANGE:
218 	case SNDRV_SEQ_EVENT_ECHO:
219 	not_yet:
220 	default:
221 		/*pr_debug("ALSA: seq_midi_emul: Unimplemented event %d\n", ev->type);*/
222 		break;
223 	}
224 }
225 EXPORT_SYMBOL(snd_midi_process_event);
226 
227 
228 /*
229  * release note
230  */
231 static void
232 note_off(struct snd_midi_op *ops, void *drv, struct snd_midi_channel *chan,
233 	 int note, int vel)
234 {
235 	if (chan->gm_hold) {
236 		/* Hold this note until pedal is turned off */
237 		chan->note[note] |= SNDRV_MIDI_NOTE_RELEASED;
238 	} else if (chan->note[note] & SNDRV_MIDI_NOTE_SOSTENUTO) {
239 		/* Mark this note as release; it will be turned off when sostenuto
240 		 * is turned off */
241 		chan->note[note] |= SNDRV_MIDI_NOTE_RELEASED;
242 	} else {
243 		chan->note[note] = 0;
244 		if (ops->note_off)
245 			ops->note_off(drv, note, vel, chan);
246 	}
247 }
248 
249 /*
250  * Do all driver independent operations for this controller and pass
251  * events that need to take place immediately to the driver.
252  */
253 static void
254 do_control(struct snd_midi_op *ops, void *drv, struct snd_midi_channel_set *chset,
255 	   struct snd_midi_channel *chan, int control, int value)
256 {
257 	int  i;
258 
259 	if (control >= ARRAY_SIZE(chan->control))
260 		return;
261 
262 	/* Switches */
263 	if ((control >=64 && control <=69) || (control >= 80 && control <= 83)) {
264 		/* These are all switches; either off or on so set to 0 or 127 */
265 		value = (value >= 64)? 127: 0;
266 	}
267 	chan->control[control] = value;
268 
269 	switch (control) {
270 	case MIDI_CTL_SUSTAIN:
271 		if (value == 0) {
272 			/* Sustain has been released, turn off held notes */
273 			for (i = 0; i < 128; i++) {
274 				if (chan->note[i] & SNDRV_MIDI_NOTE_RELEASED) {
275 					chan->note[i] = SNDRV_MIDI_NOTE_OFF;
276 					if (ops->note_off)
277 						ops->note_off(drv, i, 0, chan);
278 				}
279 			}
280 		}
281 		break;
282 	case MIDI_CTL_PORTAMENTO:
283 		break;
284 	case MIDI_CTL_SOSTENUTO:
285 		if (value) {
286 			/* Mark each note that is currently held down */
287 			for (i = 0; i < 128; i++) {
288 				if (chan->note[i] & SNDRV_MIDI_NOTE_ON)
289 					chan->note[i] |= SNDRV_MIDI_NOTE_SOSTENUTO;
290 			}
291 		} else {
292 			/* release all notes that were held */
293 			for (i = 0; i < 128; i++) {
294 				if (chan->note[i] & SNDRV_MIDI_NOTE_SOSTENUTO) {
295 					chan->note[i] &= ~SNDRV_MIDI_NOTE_SOSTENUTO;
296 					if (chan->note[i] & SNDRV_MIDI_NOTE_RELEASED) {
297 						chan->note[i] = SNDRV_MIDI_NOTE_OFF;
298 						if (ops->note_off)
299 							ops->note_off(drv, i, 0, chan);
300 					}
301 				}
302 			}
303 		}
304 		break;
305 	case MIDI_CTL_MSB_DATA_ENTRY:
306 		chan->control[MIDI_CTL_LSB_DATA_ENTRY] = 0;
307 		/* fall through */
308 	case MIDI_CTL_LSB_DATA_ENTRY:
309 		if (chan->param_type == SNDRV_MIDI_PARAM_TYPE_REGISTERED)
310 			rpn(ops, drv, chan, chset);
311 		else
312 			nrpn(ops, drv, chan, chset);
313 		break;
314 	case MIDI_CTL_REGIST_PARM_NUM_LSB:
315 	case MIDI_CTL_REGIST_PARM_NUM_MSB:
316 		chan->param_type = SNDRV_MIDI_PARAM_TYPE_REGISTERED;
317 		break;
318 	case MIDI_CTL_NONREG_PARM_NUM_LSB:
319 	case MIDI_CTL_NONREG_PARM_NUM_MSB:
320 		chan->param_type = SNDRV_MIDI_PARAM_TYPE_NONREGISTERED;
321 		break;
322 
323 	case MIDI_CTL_ALL_SOUNDS_OFF:
324 		all_sounds_off(ops, drv, chan);
325 		break;
326 
327 	case MIDI_CTL_ALL_NOTES_OFF:
328 		all_notes_off(ops, drv, chan);
329 		break;
330 
331 	case MIDI_CTL_MSB_BANK:
332 		if (chset->midi_mode == SNDRV_MIDI_MODE_XG) {
333 			if (value == 127)
334 				chan->drum_channel = 1;
335 			else
336 				chan->drum_channel = 0;
337 		}
338 		break;
339 	case MIDI_CTL_LSB_BANK:
340 		break;
341 
342 	case MIDI_CTL_RESET_CONTROLLERS:
343 		snd_midi_reset_controllers(chan);
344 		break;
345 
346 	case MIDI_CTL_SOFT_PEDAL:
347 	case MIDI_CTL_LEGATO_FOOTSWITCH:
348 	case MIDI_CTL_HOLD2:
349 	case MIDI_CTL_SC1_SOUND_VARIATION:
350 	case MIDI_CTL_SC2_TIMBRE:
351 	case MIDI_CTL_SC3_RELEASE_TIME:
352 	case MIDI_CTL_SC4_ATTACK_TIME:
353 	case MIDI_CTL_SC5_BRIGHTNESS:
354 	case MIDI_CTL_E1_REVERB_DEPTH:
355 	case MIDI_CTL_E2_TREMOLO_DEPTH:
356 	case MIDI_CTL_E3_CHORUS_DEPTH:
357 	case MIDI_CTL_E4_DETUNE_DEPTH:
358 	case MIDI_CTL_E5_PHASER_DEPTH:
359 		goto notyet;
360 	notyet:
361 	default:
362 		if (ops->control)
363 			ops->control(drv, control, chan);
364 		break;
365 	}
366 }
367 
368 
369 /*
370  * initialize the MIDI status
371  */
372 void
373 snd_midi_channel_set_clear(struct snd_midi_channel_set *chset)
374 {
375 	int i;
376 
377 	chset->midi_mode = SNDRV_MIDI_MODE_GM;
378 	chset->gs_master_volume = 127;
379 
380 	for (i = 0; i < chset->max_channels; i++) {
381 		struct snd_midi_channel *chan = chset->channels + i;
382 		memset(chan->note, 0, sizeof(chan->note));
383 
384 		chan->midi_aftertouch = 0;
385 		chan->midi_pressure = 0;
386 		chan->midi_program = 0;
387 		chan->midi_pitchbend = 0;
388 		snd_midi_reset_controllers(chan);
389 		chan->gm_rpn_pitch_bend_range = 256; /* 2 semitones */
390 		chan->gm_rpn_fine_tuning = 0;
391 		chan->gm_rpn_coarse_tuning = 0;
392 
393 		if (i == 9)
394 			chan->drum_channel = 1;
395 		else
396 			chan->drum_channel = 0;
397 	}
398 }
399 EXPORT_SYMBOL(snd_midi_channel_set_clear);
400 
401 /*
402  * Process a rpn message.
403  */
404 static void
405 rpn(struct snd_midi_op *ops, void *drv, struct snd_midi_channel *chan,
406     struct snd_midi_channel_set *chset)
407 {
408 	int type;
409 	int val;
410 
411 	if (chset->midi_mode != SNDRV_MIDI_MODE_NONE) {
412 		type = (chan->control[MIDI_CTL_REGIST_PARM_NUM_MSB] << 8) |
413 			chan->control[MIDI_CTL_REGIST_PARM_NUM_LSB];
414 		val = (chan->control[MIDI_CTL_MSB_DATA_ENTRY] << 7) |
415 			chan->control[MIDI_CTL_LSB_DATA_ENTRY];
416 
417 		switch (type) {
418 		case 0x0000: /* Pitch bend sensitivity */
419 			/* MSB only / 1 semitone per 128 */
420 			chan->gm_rpn_pitch_bend_range = val;
421 			break;
422 
423 		case 0x0001: /* fine tuning: */
424 			/* MSB/LSB, 8192=center, 100/8192 cent step */
425 			chan->gm_rpn_fine_tuning = val - 8192;
426 			break;
427 
428 		case 0x0002: /* coarse tuning */
429 			/* MSB only / 8192=center, 1 semitone per 128 */
430 			chan->gm_rpn_coarse_tuning = val - 8192;
431 			break;
432 
433 		case 0x7F7F: /* "lock-in" RPN */
434 			/* ignored */
435 			break;
436 		}
437 	}
438 	/* should call nrpn or rpn callback here.. */
439 }
440 
441 /*
442  * Process an nrpn message.
443  */
444 static void
445 nrpn(struct snd_midi_op *ops, void *drv, struct snd_midi_channel *chan,
446      struct snd_midi_channel_set *chset)
447 {
448 	/* parse XG NRPNs here if possible */
449 	if (ops->nrpn)
450 		ops->nrpn(drv, chan, chset);
451 }
452 
453 
454 /*
455  * convert channel parameter in GS sysex
456  */
457 static int
458 get_channel(unsigned char cmd)
459 {
460 	int p = cmd & 0x0f;
461 	if (p == 0)
462 		p = 9;
463 	else if (p < 10)
464 		p--;
465 	return p;
466 }
467 
468 
469 /*
470  * Process a sysex message.
471  */
472 static void
473 sysex(struct snd_midi_op *ops, void *private, unsigned char *buf, int len,
474       struct snd_midi_channel_set *chset)
475 {
476 	/* GM on */
477 	static unsigned char gm_on_macro[] = {
478 		0x7e,0x7f,0x09,0x01,
479 	};
480 	/* XG on */
481 	static unsigned char xg_on_macro[] = {
482 		0x43,0x10,0x4c,0x00,0x00,0x7e,0x00,
483 	};
484 	/* GS prefix
485 	 * drum channel: XX=0x1?(channel), YY=0x15, ZZ=on/off
486 	 * reverb mode: XX=0x01, YY=0x30, ZZ=0-7
487 	 * chorus mode: XX=0x01, YY=0x38, ZZ=0-7
488 	 * master vol:  XX=0x00, YY=0x04, ZZ=0-127
489 	 */
490 	static unsigned char gs_pfx_macro[] = {
491 		0x41,0x10,0x42,0x12,0x40,/*XX,YY,ZZ*/
492 	};
493 
494 	int parsed = SNDRV_MIDI_SYSEX_NOT_PARSED;
495 
496 	if (len <= 0 || buf[0] != 0xf0)
497 		return;
498 	/* skip first byte */
499 	buf++;
500 	len--;
501 
502 	/* GM on */
503 	if (len >= (int)sizeof(gm_on_macro) &&
504 	    memcmp(buf, gm_on_macro, sizeof(gm_on_macro)) == 0) {
505 		if (chset->midi_mode != SNDRV_MIDI_MODE_GS &&
506 		    chset->midi_mode != SNDRV_MIDI_MODE_XG) {
507 			chset->midi_mode = SNDRV_MIDI_MODE_GM;
508 			reset_all_channels(chset);
509 			parsed = SNDRV_MIDI_SYSEX_GM_ON;
510 		}
511 	}
512 
513 	/* GS macros */
514 	else if (len >= 8 &&
515 		 memcmp(buf, gs_pfx_macro, sizeof(gs_pfx_macro)) == 0) {
516 		if (chset->midi_mode != SNDRV_MIDI_MODE_GS &&
517 		    chset->midi_mode != SNDRV_MIDI_MODE_XG)
518 			chset->midi_mode = SNDRV_MIDI_MODE_GS;
519 
520 		if (buf[5] == 0x00 && buf[6] == 0x7f && buf[7] == 0x00) {
521 			/* GS reset */
522 			parsed = SNDRV_MIDI_SYSEX_GS_RESET;
523 			reset_all_channels(chset);
524 		}
525 
526 		else if ((buf[5] & 0xf0) == 0x10 && buf[6] == 0x15) {
527 			/* drum pattern */
528 			int p = get_channel(buf[5]);
529 			if (p < chset->max_channels) {
530 				parsed = SNDRV_MIDI_SYSEX_GS_DRUM_CHANNEL;
531 				if (buf[7])
532 					chset->channels[p].drum_channel = 1;
533 				else
534 					chset->channels[p].drum_channel = 0;
535 			}
536 
537 		} else if ((buf[5] & 0xf0) == 0x10 && buf[6] == 0x21) {
538 			/* program */
539 			int p = get_channel(buf[5]);
540 			if (p < chset->max_channels &&
541 			    ! chset->channels[p].drum_channel) {
542 				parsed = SNDRV_MIDI_SYSEX_GS_DRUM_CHANNEL;
543 				chset->channels[p].midi_program = buf[7];
544 			}
545 
546 		} else if (buf[5] == 0x01 && buf[6] == 0x30) {
547 			/* reverb mode */
548 			parsed = SNDRV_MIDI_SYSEX_GS_REVERB_MODE;
549 			chset->gs_reverb_mode = buf[7];
550 
551 		} else if (buf[5] == 0x01 && buf[6] == 0x38) {
552 			/* chorus mode */
553 			parsed = SNDRV_MIDI_SYSEX_GS_CHORUS_MODE;
554 			chset->gs_chorus_mode = buf[7];
555 
556 		} else if (buf[5] == 0x00 && buf[6] == 0x04) {
557 			/* master volume */
558 			parsed = SNDRV_MIDI_SYSEX_GS_MASTER_VOLUME;
559 			chset->gs_master_volume = buf[7];
560 
561 		}
562 	}
563 
564 	/* XG on */
565 	else if (len >= (int)sizeof(xg_on_macro) &&
566 		 memcmp(buf, xg_on_macro, sizeof(xg_on_macro)) == 0) {
567 		int i;
568 		chset->midi_mode = SNDRV_MIDI_MODE_XG;
569 		parsed = SNDRV_MIDI_SYSEX_XG_ON;
570 		/* reset CC#0 for drums */
571 		for (i = 0; i < chset->max_channels; i++) {
572 			if (chset->channels[i].drum_channel)
573 				chset->channels[i].control[MIDI_CTL_MSB_BANK] = 127;
574 			else
575 				chset->channels[i].control[MIDI_CTL_MSB_BANK] = 0;
576 		}
577 	}
578 
579 	if (ops->sysex)
580 		ops->sysex(private, buf - 1, len + 1, parsed, chset);
581 }
582 
583 /*
584  * all sound off
585  */
586 static void
587 all_sounds_off(struct snd_midi_op *ops, void *drv, struct snd_midi_channel *chan)
588 {
589 	int n;
590 
591 	if (! ops->note_terminate)
592 		return;
593 	for (n = 0; n < 128; n++) {
594 		if (chan->note[n]) {
595 			ops->note_terminate(drv, n, chan);
596 			chan->note[n] = 0;
597 		}
598 	}
599 }
600 
601 /*
602  * all notes off
603  */
604 static void
605 all_notes_off(struct snd_midi_op *ops, void *drv, struct snd_midi_channel *chan)
606 {
607 	int n;
608 
609 	if (! ops->note_off)
610 		return;
611 	for (n = 0; n < 128; n++) {
612 		if (chan->note[n] == SNDRV_MIDI_NOTE_ON)
613 			note_off(ops, drv, chan, n, 0);
614 	}
615 }
616 
617 /*
618  * Initialise a single midi channel control block.
619  */
620 static void snd_midi_channel_init(struct snd_midi_channel *p, int n)
621 {
622 	if (p == NULL)
623 		return;
624 
625 	memset(p, 0, sizeof(struct snd_midi_channel));
626 	p->private = NULL;
627 	p->number = n;
628 
629 	snd_midi_reset_controllers(p);
630 	p->gm_rpn_pitch_bend_range = 256; /* 2 semitones */
631 	p->gm_rpn_fine_tuning = 0;
632 	p->gm_rpn_coarse_tuning = 0;
633 
634 	if (n == 9)
635 		p->drum_channel = 1;	/* Default ch 10 as drums */
636 }
637 
638 /*
639  * Allocate and initialise a set of midi channel control blocks.
640  */
641 static struct snd_midi_channel *snd_midi_channel_init_set(int n)
642 {
643 	struct snd_midi_channel *chan;
644 	int  i;
645 
646 	chan = kmalloc_array(n, sizeof(struct snd_midi_channel), GFP_KERNEL);
647 	if (chan) {
648 		for (i = 0; i < n; i++)
649 			snd_midi_channel_init(chan+i, i);
650 	}
651 
652 	return chan;
653 }
654 
655 /*
656  * reset all midi channels
657  */
658 static void
659 reset_all_channels(struct snd_midi_channel_set *chset)
660 {
661 	int ch;
662 	for (ch = 0; ch < chset->max_channels; ch++) {
663 		struct snd_midi_channel *chan = chset->channels + ch;
664 		snd_midi_reset_controllers(chan);
665 		chan->gm_rpn_pitch_bend_range = 256; /* 2 semitones */
666 		chan->gm_rpn_fine_tuning = 0;
667 		chan->gm_rpn_coarse_tuning = 0;
668 
669 		if (ch == 9)
670 			chan->drum_channel = 1;
671 		else
672 			chan->drum_channel = 0;
673 	}
674 }
675 
676 
677 /*
678  * Allocate and initialise a midi channel set.
679  */
680 struct snd_midi_channel_set *snd_midi_channel_alloc_set(int n)
681 {
682 	struct snd_midi_channel_set *chset;
683 
684 	chset = kmalloc(sizeof(*chset), GFP_KERNEL);
685 	if (chset) {
686 		chset->channels = snd_midi_channel_init_set(n);
687 		chset->private_data = NULL;
688 		chset->max_channels = n;
689 	}
690 	return chset;
691 }
692 EXPORT_SYMBOL(snd_midi_channel_alloc_set);
693 
694 /*
695  * Reset the midi controllers on a particular channel to default values.
696  */
697 static void snd_midi_reset_controllers(struct snd_midi_channel *chan)
698 {
699 	memset(chan->control, 0, sizeof(chan->control));
700 	chan->gm_volume = 127;
701 	chan->gm_expression = 127;
702 	chan->gm_pan = 64;
703 }
704 
705 
706 /*
707  * Free a midi channel set.
708  */
709 void snd_midi_channel_free_set(struct snd_midi_channel_set *chset)
710 {
711 	if (chset == NULL)
712 		return;
713 	kfree(chset->channels);
714 	kfree(chset);
715 }
716 EXPORT_SYMBOL(snd_midi_channel_free_set);
717