summaryrefslogtreecommitdiffstats
path: root/sound/core/seq/seq_virmidi.c
blob: e4f512aa742662ed95c595bb8634b67dadb74420 (plain)
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
/*
 *  Virtual Raw MIDI client on Sequencer
 *
 *  Copyright (c) 2000 by Takashi Iwai <tiwai@suse.de>,
 *                        Jaroslav Kysela <perex@perex.cz>
 *
 *   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
 *
 */

/*
 * Virtual Raw MIDI client
 *
 * The virtual rawmidi client is a sequencer client which associate
 * a rawmidi device file.  The created rawmidi device file can be
 * accessed as a normal raw midi, but its MIDI source and destination
 * are arbitrary.  For example, a user-client software synth connected
 * to this port can be used as a normal midi device as well.
 *
 * The virtual rawmidi device accepts also multiple opens.  Each file
 * has its own input buffer, so that no conflict would occur.  The drain
 * of input/output buffer acts only to the local buffer.
 *
 */

#include <sound/driver.h>
#include <linux/init.h>
#include <linux/wait.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <sound/core.h>
#include <sound/rawmidi.h>
#include <sound/info.h>
#include <sound/control.h>
#include <sound/minors.h>
#include <sound/seq_kernel.h>
#include <sound/seq_midi_event.h>
#include <sound/seq_virmidi.h>

MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>");
MODULE_DESCRIPTION("Virtual Raw MIDI client on Sequencer");
MODULE_LICENSE("GPL");

/*
 * initialize an event record
 */
static void snd_virmidi_init_event(snd_virmidi_t *vmidi, snd_seq_event_t *ev)
{
	memset(ev, 0, sizeof(*ev));
	ev->source.port = vmidi->port;
	switch (vmidi->seq_mode) {
	case SNDRV_VIRMIDI_SEQ_DISPATCH:
		ev->dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS;
		break;
	case SNDRV_VIRMIDI_SEQ_ATTACH:
		/* FIXME: source and destination are same - not good.. */
		ev->dest.client = vmidi->client;
		ev->dest.port = vmidi->port;
		break;
	}
	ev->type = SNDRV_SEQ_EVENT_NONE;
}

/*
 * decode input event and put to read buffer of each opened file
 */
static int snd_virmidi_dev_receive_event(snd_virmidi_dev_t *rdev, snd_seq_event_t *ev)
{
	snd_virmidi_t *vmidi;
	struct list_head *list;
	unsigned char msg[4];
	int len;

	read_lock(&rdev->filelist_lock);
	list_for_each(list, &rdev->filelist) {
		vmidi = list_entry(list, snd_virmidi_t, list);
		if (!vmidi->trigger)
			continue;
		if (ev->type == SNDRV_SEQ_EVENT_SYSEX) {
			if ((ev->flags & SNDRV_SEQ_EVENT_LENGTH_MASK) != SNDRV_SEQ_EVENT_LENGTH_VARIABLE)
				continue;
			snd_seq_dump_var_event(ev, (snd_seq_dump_func_t)snd_rawmidi_receive, vmidi->substream);
		} else {
			len = snd_midi_event_decode(vmidi->parser, msg, sizeof(msg), ev);
			if (len > 0)
				snd_rawmidi_receive(vmidi->substream, msg, len);
		}
	}
	read_unlock(&rdev->filelist_lock);

	return 0;
}

/*
 * receive an event from the remote virmidi port
 *
 * for rawmidi inputs, you can call this function from the event
 * handler of a remote port which is attached to the virmidi via
 * SNDRV_VIRMIDI_SEQ_ATTACH.
 */
#if 0
int snd_virmidi_receive(snd_rawmidi_t *rmidi, snd_seq_event_t *ev)
{
	snd_virmidi_dev_t *rdev;

	rdev = rmidi->private_data;
	return snd_virmidi_dev_receive_event(rdev, ev);
}
#endif  /*  0  */

/*
 * event handler of virmidi port
 */
static int snd_virmidi_event_input(snd_seq_event_t *ev, int direct,
				   void *private_data, int atomic, int hop)
{
	snd_virmidi_dev_t *rdev;

	rdev = private_data;
	if (!(rdev->flags & SNDRV_VIRMIDI_USE))
		return 0; /* ignored */
	return snd_virmidi_dev_receive_event(rdev, ev);
}

/*
 * trigger rawmidi stream for input
 */
static void snd_virmidi_input_trigger(snd_rawmidi_substream_t * substream, int up)
{
	snd_virmidi_t *vmidi = substream->runtime->private_data;

	if (up) {
		vmidi->trigger = 1;
	} else {
		vmidi->trigger = 0;
	}
}

/*
 * trigger rawmidi stream for output
 */
static void snd_virmidi_output_trigger(snd_rawmidi_substream_t * substream, int up)
{
	snd_virmidi_t *vmidi = substream->runtime->private_data;
	int count, res;
	unsigned char buf[32], *pbuf;

	if (up) {
		vmidi->trigger = 1;
		if (vmidi->seq_mode == SNDRV_VIRMIDI_SEQ_DISPATCH &&
		    !(vmidi->rdev->flags & SNDRV_VIRMIDI_SUBSCRIBE)) {
			snd_rawmidi_transmit_ack(substream, substream->runtime->buffer_size - substream->runtime->avail);
			return;		/* ignored */
		}
		if (vmidi->event.type != SNDRV_SEQ_EVENT_NONE) {
			if (snd_seq_kernel_client_dispatch(vmidi->client, &vmidi->event, 0, 0) < 0)
				return;
			vmidi->event.type = SNDRV_SEQ_EVENT_NONE;
		}
		while (1) {
			count = snd_rawmidi_transmit_peek(substream, buf, sizeof(buf));
			if (count <= 0)
				break;
			pbuf = buf;
			while (count > 0) {
				res = snd_midi_event_encode(vmidi->parser, pbuf, count, &vmidi->event);
				if (res < 0) {
					snd_midi_event_reset_encode(vmidi->parser);
					continue;
				}
				snd_rawmidi_transmit_ack(substream, res);
				pbuf += res;
				count -= res;
				if (vmidi->event.type != SNDRV_SEQ_EVENT_NONE) {
					if (snd_seq_kernel_client_dispatch(vmidi->client, &vmidi->event, 0, 0) < 0)
						return;
					vmidi->event.type = SNDRV_SEQ_EVENT_NONE;
				}
			}
		}
	} else {
		vmidi->trigger = 0;
	}
}

/*
 * open rawmidi handle for input
 */
static int snd_virmidi_input_open(snd_rawmidi_substream_t * substream)
{
	snd_virmidi_dev_t *rdev = substream->rmidi->private_data;
	snd_rawmidi_runtime_t *runtime = substream->runtime;
	snd_virmidi_t *vmidi;
	unsigned long flags;

	vmidi = kzalloc(sizeof(*vmidi), GFP_KERNEL);
	if (vmidi == NULL)
		return -ENOMEM;
	vmidi->substream = substream;
	if (snd_midi_event_new(0, &vmidi->parser) < 0) {
		kfree(vmidi);
		return -ENOMEM;
	}
	vmidi->seq_mode = rdev->seq_mode;
	vmidi->client = rdev->client;
	vmidi->port = rdev->port;	
	runtime->private_data = vmidi;
	write_lock_irqsave(&rdev->filelist_lock, flags);
	list_add_tail(&vmidi->list, &rdev->filelist);
	write_unlock_irqrestore(&rdev->filelist_lock, flags);
	vmidi->rdev = rdev;
	return 0;
}

/*
 * open rawmidi handle for output
 */
static int snd_virmidi_output_open(snd_rawmidi_substream_t * substream)
{
	snd_virmidi_dev_t *rdev = substream->rmidi->private_data;
	snd_rawmidi_runtime_t *runtime = substream->runtime;
	snd_virmidi_t *vmidi;

	vmidi = kzalloc(sizeof(*vmidi), GFP_KERNEL);
	if (vmidi == NULL)
		return -ENOMEM;
	vmidi->substream = substream;
	if (snd_midi_event_new(MAX_MIDI_EVENT_BUF, &vmidi->parser) < 0) {
		kfree(vmidi);
		return -ENOMEM;
	}
	vmidi->seq_mode = rdev->seq_mode;
	vmidi->client = rdev->client;
	vmidi->port = rdev->port;
	snd_virmidi_init_event(vmidi, &vmidi->event);
	vmidi->rdev = rdev;
	runtime->private_data = vmidi;
	return 0;
}

/*
 * close rawmidi handle for input
 */
static int snd_virmidi_input_close(snd_rawmidi_substream_t * substream)
{
	snd_virmidi_t *vmidi = substream->runtime->private_data;
	snd_midi_event_free(vmidi->parser);
	list_del(&vmidi->list);
	substream->runtime->private_data = NULL;
	kfree(vmidi);
	return 0;
}

/*
 * close rawmidi handle for output
 */
static int snd_virmidi_output_close(snd_rawmidi_substream_t * substream)
{
	snd_virmidi_t *vmidi = substream->runtime->private_data;
	snd_midi_event_free(vmidi->parser);
	substream->runtime->private_data = NULL;
	kfree(vmidi);
	return 0;
}

/*
 * subscribe callback - allow output to rawmidi device
 */
static int snd_virmidi_subscribe(void *private_data, snd_seq_port_subscribe_t *info)
{
	snd_virmidi_dev_t *rdev;

	rdev = private_data;
	if (!try_module_get(rdev->card->module))
		return -EFAULT;
	rdev->flags |= SNDRV_VIRMIDI_SUBSCRIBE;
	return 0;
}

/*
 * unsubscribe callback - disallow output to rawmidi device
 */
static int snd_virmidi_unsubscribe(void *private_data, snd_seq_port_subscribe_t *info)
{
	snd_virmidi_dev_t *rdev;

	rdev = private_data;
	rdev->flags &= ~SNDRV_VIRMIDI_SUBSCRIBE;
	module_put(rdev->card->module);
	return 0;
}


/*
 * use callback - allow input to rawmidi device
 */
static int snd_virmidi_use(void *private_data, snd_seq_port_subscribe_t *info)
{
	snd_virmidi_dev_t *rdev;

	rdev = private_data;
	if (!try_module_get(rdev->card->module))
		return -EFAULT;
	rdev->flags |= SNDRV_VIRMIDI_USE;
	return 0;
}

/*
 * unuse callback - disallow input to rawmidi device
 */
static int snd_virmidi_unuse(void *private_data, snd_seq_port_subscribe_t *info)
{
	snd_virmidi_dev_t *rdev;

	rdev = private_data;
	rdev->flags &= ~SNDRV_VIRMIDI_USE;
	module_put(rdev->card->module);
	return 0;
}


/*
 *  Register functions
 */

static snd_rawmidi_ops_t snd_virmidi_input_ops = {
	.open = snd_virmidi_input_open,
	.close = snd_virmidi_input_close,
	.trigger = snd_virmidi_input_trigger,
};

static snd_rawmidi_ops_t snd_virmidi_output_ops = {
	.open = snd_virmidi_output_open,
	.close = snd_virmidi_output_close,
	.trigger = snd_virmidi_output_trigger,
};

/*
 * create a sequencer client and a port
 */
static int snd_virmidi_dev_attach_seq(snd_virmidi_dev_t *rdev)
{
	int client;
	snd_seq_client_callback_t callbacks;
	snd_seq_port_callback_t pcallbacks;
	snd_seq_client_info_t *info;
	snd_seq_port_info_t *pinfo;
	int err;

	if (rdev->client >= 0)
		return 0;

	info = kmalloc(sizeof(*info), GFP_KERNEL);
	pinfo = kmalloc(sizeof(*pinfo), GFP_KERNEL);
	if (! info || ! pinfo) {
		err = -ENOMEM;
		goto __error;
	}

	memset(&callbacks, 0, sizeof(callbacks));
	callbacks.private_data = rdev;
	callbacks.allow_input = 1;
	callbacks.allow_output = 1;
	client = snd_seq_create_kernel_client(rdev->card, rdev->device, &callbacks);
	if (client < 0) {
		err = client;
		goto __error;
	}
	rdev->client = client;

	/* set client name */
	memset(info, 0, sizeof(*info));
	info->client = client;
	info->type = KERNEL_CLIENT;
	sprintf(info->name, "%s %d-%d", rdev->rmidi->name, rdev->card->number, rdev->device);
	snd_seq_kernel_client_ctl(client, SNDRV_SEQ_IOCTL_SET_CLIENT_INFO, info);

	/* create a port */
	memset(pinfo, 0, sizeof(*pinfo));
	pinfo->addr.client = client;
	sprintf(pinfo->name, "VirMIDI %d-%d", rdev->card->number, rdev->device);
	/* set all capabilities */
	pinfo->capability |= SNDRV_SEQ_PORT_CAP_WRITE | SNDRV_SEQ_PORT_CAP_SYNC_WRITE | SNDRV_SEQ_PORT_CAP_SUBS_WRITE;
	pinfo->capability |= SNDRV_SEQ_PORT_CAP_READ | SNDRV_SEQ_PORT_CAP_SYNC_READ | SNDRV_SEQ_PORT_CAP_SUBS_READ;
	pinfo->capability |= SNDRV_SEQ_PORT_CAP_DUPLEX;
	pinfo->type = SNDRV_SEQ_PORT_TYPE_MIDI_GENERIC;
	pinfo->midi_channels = 16;
	memset(&pcallbacks, 0, sizeof(pcallbacks));
	pcallbacks.owner = THIS_MODULE;
	pcallbacks.private_data = rdev;
	pcallbacks.subscribe = snd_virmidi_subscribe;
	pcallbacks.unsubscribe = snd_virmidi_unsubscribe;
	pcallbacks.use = snd_virmidi_use;
	pcallbacks.unuse = snd_virmidi_unuse;
	pcallbacks.event_input = snd_virmidi_event_input;
	pinfo->kernel = &pcallbacks;
	err = snd_seq_kernel_client_ctl(client, SNDRV_SEQ_IOCTL_CREATE_PORT, pinfo);
	if (err < 0) {
		snd_seq_delete_kernel_client(client);
		rdev->client = -1;
		goto __error;
	}

	rdev->port = pinfo->addr.port;
	err = 0; /* success */

 __error:
	kfree(info);
	kfree(pinfo);
	return err;
}


/*
 * release the sequencer client
 */
static void snd_virmidi_dev_detach_seq(snd_virmidi_dev_t *rdev)
{
	if (rdev->client >= 0) {
		snd_seq_delete_kernel_client(rdev->client);
		rdev->client = -1;
	}
}

/*
 * register the device
 */
static int snd_virmidi_dev_register(snd_rawmidi_t *rmidi)
{
	snd_virmidi_dev_t *rdev = rmidi->private_data;
	int err;

	switch (rdev->seq_mode) {
	case SNDRV_VIRMIDI_SEQ_DISPATCH:
		err = snd_virmidi_dev_attach_seq(rdev);
		if (err < 0)
			return err;
		break;
	case SNDRV_VIRMIDI_SEQ_ATTACH:
		if (rdev->client == 0)
			return -EINVAL;
		/* should check presence of port more strictly.. */
		break;
	default:
		snd_printk(KERN_ERR "seq_mode is not set: %d\n", rdev->seq_mode);
		return -EINVAL;
	}
	return 0;
}


/*
 * unregister the device
 */
static int snd_virmidi_dev_unregister(snd_rawmidi_t *rmidi)
{
	snd_virmidi_dev_t *rdev = rmidi->private_data;

	if (rdev->seq_mode == SNDRV_VIRMIDI_SEQ_DISPATCH)
		snd_virmidi_dev_detach_seq(rdev);
	return 0;
}

/*
 *
 */
static snd_rawmidi_global_ops_t snd_virmidi_global_ops = {
	.dev_register = snd_virmidi_dev_register,
	.dev_unregister = snd_virmidi_dev_unregister,
};

/*
 * free device
 */
static void snd_virmidi_free(snd_rawmidi_t *rmidi)
{
	snd_virmidi_dev_t *rdev = rmidi->private_data;
	kfree(rdev);
}

/*
 * create a new device
 *
 */
/* exported */
int snd_virmidi_new(snd_card_t *card, int device, snd_rawmidi_t **rrmidi)
{
	snd_rawmidi_t *rmidi;
	snd_virmidi_dev_t *rdev;
	int err;
	
	*rrmidi = NULL;
	if ((err = snd_rawmidi_new(card, "VirMidi", device,
				   16,	/* may be configurable */
				   16,	/* may be configurable */
				   &rmidi)) < 0)
		return err;
	strcpy(rmidi->name, rmidi->id);
	rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
	if (rdev == NULL) {
		snd_device_free(card, rmidi);
		return -ENOMEM;
	}
	rdev->card = card;
	rdev->rmidi = rmidi;
	rdev->device = device;
	rdev->client = -1;
	rwlock_init(&rdev->filelist_lock);
	INIT_LIST_HEAD(&rdev->filelist);
	rdev->seq_mode = SNDRV_VIRMIDI_SEQ_DISPATCH;
	rmidi->private_data = rdev;
	rmidi->private_free = snd_virmidi_free;
	rmidi->ops = &snd_virmidi_global_ops;
	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_virmidi_input_ops);
	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &snd_virmidi_output_ops);
	rmidi->info_flags = SNDRV_RAWMIDI_INFO_INPUT |
			    SNDRV_RAWMIDI_INFO_OUTPUT |
			    SNDRV_RAWMIDI_INFO_DUPLEX;
	*rrmidi = rmidi;
	return 0;
}

/*
 *  ENTRY functions
 */

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

static void __exit alsa_virmidi_exit(void)
{
}

module_init(alsa_virmidi_init)
module_exit(alsa_virmidi_exit)

EXPORT_SYMBOL(snd_virmidi_new);
OpenPOWER on IntegriCloud