2 * Virtual Raw MIDI client on Sequencer
4 * Copyright (c) 2000 by Takashi Iwai <tiwai@suse.de>,
5 * Jaroslav Kysela <perex@perex.cz>
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.
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.
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
24 * Virtual Raw MIDI client
26 * The virtual rawmidi client is a sequencer client which associate
27 * a rawmidi device file. The created rawmidi device file can be
28 * accessed as a normal raw midi, but its MIDI source and destination
29 * are arbitrary. For example, a user-client software synth connected
30 * to this port can be used as a normal midi device as well.
32 * The virtual rawmidi device accepts also multiple opens. Each file
33 * has its own input buffer, so that no conflict would occur. The drain
34 * of input/output buffer acts only to the local buffer.
38 #include <linux/init.h>
39 #include <linux/wait.h>
40 #include <linux/module.h>
41 #include <linux/slab.h>
42 #include <sound/core.h>
43 #include <sound/rawmidi.h>
44 #include <sound/info.h>
45 #include <sound/control.h>
46 #include <sound/minors.h>
47 #include <sound/seq_kernel.h>
48 #include <sound/seq_midi_event.h>
49 #include <sound/seq_virmidi.h>
51 MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>");
52 MODULE_DESCRIPTION("Virtual Raw MIDI client on Sequencer");
53 MODULE_LICENSE("GPL");
56 * initialize an event record
58 static void snd_virmidi_init_event(struct snd_virmidi *vmidi,
59 struct snd_seq_event *ev)
61 memset(ev, 0, sizeof(*ev));
62 ev->source.port = vmidi->port;
63 switch (vmidi->seq_mode) {
64 case SNDRV_VIRMIDI_SEQ_DISPATCH:
65 ev->dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS;
67 case SNDRV_VIRMIDI_SEQ_ATTACH:
68 /* FIXME: source and destination are same - not good.. */
69 ev->dest.client = vmidi->client;
70 ev->dest.port = vmidi->port;
73 ev->type = SNDRV_SEQ_EVENT_NONE;
77 * decode input event and put to read buffer of each opened file
79 static int snd_virmidi_dev_receive_event(struct snd_virmidi_dev *rdev,
80 struct snd_seq_event *ev,
83 struct snd_virmidi *vmidi;
88 read_lock(&rdev->filelist_lock);
90 down_read(&rdev->filelist_sem);
91 list_for_each_entry(vmidi, &rdev->filelist, list) {
94 if (ev->type == SNDRV_SEQ_EVENT_SYSEX) {
95 if ((ev->flags & SNDRV_SEQ_EVENT_LENGTH_MASK) != SNDRV_SEQ_EVENT_LENGTH_VARIABLE)
97 snd_seq_dump_var_event(ev, (snd_seq_dump_func_t)snd_rawmidi_receive, vmidi->substream);
98 snd_midi_event_reset_decode(vmidi->parser);
100 len = snd_midi_event_decode(vmidi->parser, msg, sizeof(msg), ev);
102 snd_rawmidi_receive(vmidi->substream, msg, len);
106 read_unlock(&rdev->filelist_lock);
108 up_read(&rdev->filelist_sem);
114 * receive an event from the remote virmidi port
116 * for rawmidi inputs, you can call this function from the event
117 * handler of a remote port which is attached to the virmidi via
118 * SNDRV_VIRMIDI_SEQ_ATTACH.
121 int snd_virmidi_receive(struct snd_rawmidi *rmidi, struct snd_seq_event *ev)
123 struct snd_virmidi_dev *rdev;
125 rdev = rmidi->private_data;
126 return snd_virmidi_dev_receive_event(rdev, ev, true);
131 * event handler of virmidi port
133 static int snd_virmidi_event_input(struct snd_seq_event *ev, int direct,
134 void *private_data, int atomic, int hop)
136 struct snd_virmidi_dev *rdev;
139 if (!(rdev->flags & SNDRV_VIRMIDI_USE))
140 return 0; /* ignored */
141 return snd_virmidi_dev_receive_event(rdev, ev, atomic);
145 * trigger rawmidi stream for input
147 static void snd_virmidi_input_trigger(struct snd_rawmidi_substream *substream, int up)
149 struct snd_virmidi *vmidi = substream->runtime->private_data;
159 * trigger rawmidi stream for output
161 static void snd_virmidi_output_trigger(struct snd_rawmidi_substream *substream, int up)
163 struct snd_virmidi *vmidi = substream->runtime->private_data;
165 unsigned char buf[32], *pbuf;
167 bool check_resched = !in_atomic();
171 if (vmidi->seq_mode == SNDRV_VIRMIDI_SEQ_DISPATCH &&
172 !(vmidi->rdev->flags & SNDRV_VIRMIDI_SUBSCRIBE)) {
173 while (snd_rawmidi_transmit(substream, buf,
179 spin_lock_irqsave(&substream->runtime->lock, flags);
180 if (vmidi->event.type != SNDRV_SEQ_EVENT_NONE) {
181 if (snd_seq_kernel_client_dispatch(vmidi->client, &vmidi->event, in_atomic(), 0) < 0)
183 vmidi->event.type = SNDRV_SEQ_EVENT_NONE;
186 count = __snd_rawmidi_transmit_peek(substream, buf, sizeof(buf));
191 res = snd_midi_event_encode(vmidi->parser, pbuf, count, &vmidi->event);
193 snd_midi_event_reset_encode(vmidi->parser);
196 __snd_rawmidi_transmit_ack(substream, res);
199 if (vmidi->event.type != SNDRV_SEQ_EVENT_NONE) {
200 if (snd_seq_kernel_client_dispatch(vmidi->client, &vmidi->event, in_atomic(), 0) < 0)
202 vmidi->event.type = SNDRV_SEQ_EVENT_NONE;
207 /* do temporary unlock & cond_resched() for avoiding
208 * CPU soft lockup, which may happen via a write from
209 * a huge rawmidi buffer
211 spin_unlock_irqrestore(&substream->runtime->lock, flags);
213 spin_lock_irqsave(&substream->runtime->lock, flags);
216 spin_unlock_irqrestore(&substream->runtime->lock, flags);
223 * open rawmidi handle for input
225 static int snd_virmidi_input_open(struct snd_rawmidi_substream *substream)
227 struct snd_virmidi_dev *rdev = substream->rmidi->private_data;
228 struct snd_rawmidi_runtime *runtime = substream->runtime;
229 struct snd_virmidi *vmidi;
231 vmidi = kzalloc(sizeof(*vmidi), GFP_KERNEL);
234 vmidi->substream = substream;
235 if (snd_midi_event_new(0, &vmidi->parser) < 0) {
239 vmidi->seq_mode = rdev->seq_mode;
240 vmidi->client = rdev->client;
241 vmidi->port = rdev->port;
242 runtime->private_data = vmidi;
243 down_write(&rdev->filelist_sem);
244 write_lock_irq(&rdev->filelist_lock);
245 list_add_tail(&vmidi->list, &rdev->filelist);
246 write_unlock_irq(&rdev->filelist_lock);
247 up_write(&rdev->filelist_sem);
253 * open rawmidi handle for output
255 static int snd_virmidi_output_open(struct snd_rawmidi_substream *substream)
257 struct snd_virmidi_dev *rdev = substream->rmidi->private_data;
258 struct snd_rawmidi_runtime *runtime = substream->runtime;
259 struct snd_virmidi *vmidi;
261 vmidi = kzalloc(sizeof(*vmidi), GFP_KERNEL);
264 vmidi->substream = substream;
265 if (snd_midi_event_new(MAX_MIDI_EVENT_BUF, &vmidi->parser) < 0) {
269 vmidi->seq_mode = rdev->seq_mode;
270 vmidi->client = rdev->client;
271 vmidi->port = rdev->port;
272 snd_virmidi_init_event(vmidi, &vmidi->event);
274 runtime->private_data = vmidi;
279 * close rawmidi handle for input
281 static int snd_virmidi_input_close(struct snd_rawmidi_substream *substream)
283 struct snd_virmidi_dev *rdev = substream->rmidi->private_data;
284 struct snd_virmidi *vmidi = substream->runtime->private_data;
286 down_write(&rdev->filelist_sem);
287 write_lock_irq(&rdev->filelist_lock);
288 list_del(&vmidi->list);
289 write_unlock_irq(&rdev->filelist_lock);
290 up_write(&rdev->filelist_sem);
291 snd_midi_event_free(vmidi->parser);
292 substream->runtime->private_data = NULL;
298 * close rawmidi handle for output
300 static int snd_virmidi_output_close(struct snd_rawmidi_substream *substream)
302 struct snd_virmidi *vmidi = substream->runtime->private_data;
303 snd_midi_event_free(vmidi->parser);
304 substream->runtime->private_data = NULL;
310 * subscribe callback - allow output to rawmidi device
312 static int snd_virmidi_subscribe(void *private_data,
313 struct snd_seq_port_subscribe *info)
315 struct snd_virmidi_dev *rdev;
318 if (!try_module_get(rdev->card->module))
320 rdev->flags |= SNDRV_VIRMIDI_SUBSCRIBE;
325 * unsubscribe callback - disallow output to rawmidi device
327 static int snd_virmidi_unsubscribe(void *private_data,
328 struct snd_seq_port_subscribe *info)
330 struct snd_virmidi_dev *rdev;
333 rdev->flags &= ~SNDRV_VIRMIDI_SUBSCRIBE;
334 module_put(rdev->card->module);
340 * use callback - allow input to rawmidi device
342 static int snd_virmidi_use(void *private_data,
343 struct snd_seq_port_subscribe *info)
345 struct snd_virmidi_dev *rdev;
348 if (!try_module_get(rdev->card->module))
350 rdev->flags |= SNDRV_VIRMIDI_USE;
355 * unuse callback - disallow input to rawmidi device
357 static int snd_virmidi_unuse(void *private_data,
358 struct snd_seq_port_subscribe *info)
360 struct snd_virmidi_dev *rdev;
363 rdev->flags &= ~SNDRV_VIRMIDI_USE;
364 module_put(rdev->card->module);
373 static struct snd_rawmidi_ops snd_virmidi_input_ops = {
374 .open = snd_virmidi_input_open,
375 .close = snd_virmidi_input_close,
376 .trigger = snd_virmidi_input_trigger,
379 static struct snd_rawmidi_ops snd_virmidi_output_ops = {
380 .open = snd_virmidi_output_open,
381 .close = snd_virmidi_output_close,
382 .trigger = snd_virmidi_output_trigger,
386 * create a sequencer client and a port
388 static int snd_virmidi_dev_attach_seq(struct snd_virmidi_dev *rdev)
391 struct snd_seq_port_callback pcallbacks;
392 struct snd_seq_port_info *pinfo;
395 if (rdev->client >= 0)
398 pinfo = kzalloc(sizeof(*pinfo), GFP_KERNEL);
404 client = snd_seq_create_kernel_client(rdev->card, rdev->device,
405 "%s %d-%d", rdev->rmidi->name,
412 rdev->client = client;
415 pinfo->addr.client = client;
416 sprintf(pinfo->name, "VirMIDI %d-%d", rdev->card->number, rdev->device);
417 /* set all capabilities */
418 pinfo->capability |= SNDRV_SEQ_PORT_CAP_WRITE | SNDRV_SEQ_PORT_CAP_SYNC_WRITE | SNDRV_SEQ_PORT_CAP_SUBS_WRITE;
419 pinfo->capability |= SNDRV_SEQ_PORT_CAP_READ | SNDRV_SEQ_PORT_CAP_SYNC_READ | SNDRV_SEQ_PORT_CAP_SUBS_READ;
420 pinfo->capability |= SNDRV_SEQ_PORT_CAP_DUPLEX;
421 pinfo->type = SNDRV_SEQ_PORT_TYPE_MIDI_GENERIC
422 | SNDRV_SEQ_PORT_TYPE_SOFTWARE
423 | SNDRV_SEQ_PORT_TYPE_PORT;
424 pinfo->midi_channels = 16;
425 memset(&pcallbacks, 0, sizeof(pcallbacks));
426 pcallbacks.owner = THIS_MODULE;
427 pcallbacks.private_data = rdev;
428 pcallbacks.subscribe = snd_virmidi_subscribe;
429 pcallbacks.unsubscribe = snd_virmidi_unsubscribe;
430 pcallbacks.use = snd_virmidi_use;
431 pcallbacks.unuse = snd_virmidi_unuse;
432 pcallbacks.event_input = snd_virmidi_event_input;
433 pinfo->kernel = &pcallbacks;
434 err = snd_seq_kernel_client_ctl(client, SNDRV_SEQ_IOCTL_CREATE_PORT, pinfo);
436 snd_seq_delete_kernel_client(client);
441 rdev->port = pinfo->addr.port;
442 err = 0; /* success */
451 * release the sequencer client
453 static void snd_virmidi_dev_detach_seq(struct snd_virmidi_dev *rdev)
455 if (rdev->client >= 0) {
456 snd_seq_delete_kernel_client(rdev->client);
462 * register the device
464 static int snd_virmidi_dev_register(struct snd_rawmidi *rmidi)
466 struct snd_virmidi_dev *rdev = rmidi->private_data;
469 switch (rdev->seq_mode) {
470 case SNDRV_VIRMIDI_SEQ_DISPATCH:
471 err = snd_virmidi_dev_attach_seq(rdev);
475 case SNDRV_VIRMIDI_SEQ_ATTACH:
476 if (rdev->client == 0)
478 /* should check presence of port more strictly.. */
481 pr_err("ALSA: seq_virmidi: seq_mode is not set: %d\n", rdev->seq_mode);
489 * unregister the device
491 static int snd_virmidi_dev_unregister(struct snd_rawmidi *rmidi)
493 struct snd_virmidi_dev *rdev = rmidi->private_data;
495 if (rdev->seq_mode == SNDRV_VIRMIDI_SEQ_DISPATCH)
496 snd_virmidi_dev_detach_seq(rdev);
503 static struct snd_rawmidi_global_ops snd_virmidi_global_ops = {
504 .dev_register = snd_virmidi_dev_register,
505 .dev_unregister = snd_virmidi_dev_unregister,
511 static void snd_virmidi_free(struct snd_rawmidi *rmidi)
513 struct snd_virmidi_dev *rdev = rmidi->private_data;
518 * create a new device
522 int snd_virmidi_new(struct snd_card *card, int device, struct snd_rawmidi **rrmidi)
524 struct snd_rawmidi *rmidi;
525 struct snd_virmidi_dev *rdev;
529 if ((err = snd_rawmidi_new(card, "VirMidi", device,
530 16, /* may be configurable */
531 16, /* may be configurable */
534 strcpy(rmidi->name, rmidi->id);
535 rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
537 snd_device_free(card, rmidi);
542 rdev->device = device;
544 init_rwsem(&rdev->filelist_sem);
545 rwlock_init(&rdev->filelist_lock);
546 INIT_LIST_HEAD(&rdev->filelist);
547 rdev->seq_mode = SNDRV_VIRMIDI_SEQ_DISPATCH;
548 rmidi->private_data = rdev;
549 rmidi->private_free = snd_virmidi_free;
550 rmidi->ops = &snd_virmidi_global_ops;
551 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_virmidi_input_ops);
552 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &snd_virmidi_output_ops);
553 rmidi->info_flags = SNDRV_RAWMIDI_INFO_INPUT |
554 SNDRV_RAWMIDI_INFO_OUTPUT |
555 SNDRV_RAWMIDI_INFO_DUPLEX;
564 static int __init alsa_virmidi_init(void)
569 static void __exit alsa_virmidi_exit(void)
573 module_init(alsa_virmidi_init)
574 module_exit(alsa_virmidi_exit)
576 EXPORT_SYMBOL(snd_virmidi_new);