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v5.4
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *  Virtual Raw MIDI client on Sequencer
  4 *
  5 *  Copyright (c) 2000 by Takashi Iwai <tiwai@suse.de>,
  6 *                        Jaroslav Kysela <perex@perex.cz>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  7 */
  8
  9/*
 10 * Virtual Raw MIDI client
 11 *
 12 * The virtual rawmidi client is a sequencer client which associate
 13 * a rawmidi device file.  The created rawmidi device file can be
 14 * accessed as a normal raw midi, but its MIDI source and destination
 15 * are arbitrary.  For example, a user-client software synth connected
 16 * to this port can be used as a normal midi device as well.
 17 *
 18 * The virtual rawmidi device accepts also multiple opens.  Each file
 19 * has its own input buffer, so that no conflict would occur.  The drain
 20 * of input/output buffer acts only to the local buffer.
 21 *
 22 */
 23
 24#include <linux/init.h>
 25#include <linux/wait.h>
 26#include <linux/module.h>
 27#include <linux/slab.h>
 28#include <sound/core.h>
 29#include <sound/rawmidi.h>
 30#include <sound/info.h>
 31#include <sound/control.h>
 32#include <sound/minors.h>
 33#include <sound/seq_kernel.h>
 34#include <sound/seq_midi_event.h>
 35#include <sound/seq_virmidi.h>
 36
 37MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>");
 38MODULE_DESCRIPTION("Virtual Raw MIDI client on Sequencer");
 39MODULE_LICENSE("GPL");
 40
 41/*
 42 * initialize an event record
 43 */
 44static void snd_virmidi_init_event(struct snd_virmidi *vmidi,
 45				   struct snd_seq_event *ev)
 46{
 47	memset(ev, 0, sizeof(*ev));
 48	ev->source.port = vmidi->port;
 49	switch (vmidi->seq_mode) {
 50	case SNDRV_VIRMIDI_SEQ_DISPATCH:
 51		ev->dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS;
 52		break;
 53	case SNDRV_VIRMIDI_SEQ_ATTACH:
 54		/* FIXME: source and destination are same - not good.. */
 55		ev->dest.client = vmidi->client;
 56		ev->dest.port = vmidi->port;
 57		break;
 58	}
 59	ev->type = SNDRV_SEQ_EVENT_NONE;
 60}
 61
 62/*
 63 * decode input event and put to read buffer of each opened file
 64 */
 65static int snd_virmidi_dev_receive_event(struct snd_virmidi_dev *rdev,
 66					 struct snd_seq_event *ev,
 67					 bool atomic)
 68{
 69	struct snd_virmidi *vmidi;
 70	unsigned char msg[4];
 71	int len;
 72
 73	if (atomic)
 74		read_lock(&rdev->filelist_lock);
 75	else
 76		down_read(&rdev->filelist_sem);
 77	list_for_each_entry(vmidi, &rdev->filelist, list) {
 78		if (!READ_ONCE(vmidi->trigger))
 79			continue;
 80		if (ev->type == SNDRV_SEQ_EVENT_SYSEX) {
 81			if ((ev->flags & SNDRV_SEQ_EVENT_LENGTH_MASK) != SNDRV_SEQ_EVENT_LENGTH_VARIABLE)
 82				continue;
 83			snd_seq_dump_var_event(ev, (snd_seq_dump_func_t)snd_rawmidi_receive, vmidi->substream);
 84		} else {
 85			len = snd_midi_event_decode(vmidi->parser, msg, sizeof(msg), ev);
 86			if (len > 0)
 87				snd_rawmidi_receive(vmidi->substream, msg, len);
 88		}
 89	}
 90	if (atomic)
 91		read_unlock(&rdev->filelist_lock);
 92	else
 93		up_read(&rdev->filelist_sem);
 94
 95	return 0;
 96}
 97
 98/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 99 * event handler of virmidi port
100 */
101static int snd_virmidi_event_input(struct snd_seq_event *ev, int direct,
102				   void *private_data, int atomic, int hop)
103{
104	struct snd_virmidi_dev *rdev;
105
106	rdev = private_data;
107	if (!(rdev->flags & SNDRV_VIRMIDI_USE))
108		return 0; /* ignored */
109	return snd_virmidi_dev_receive_event(rdev, ev, atomic);
110}
111
112/*
113 * trigger rawmidi stream for input
114 */
115static void snd_virmidi_input_trigger(struct snd_rawmidi_substream *substream, int up)
116{
117	struct snd_virmidi *vmidi = substream->runtime->private_data;
118
119	WRITE_ONCE(vmidi->trigger, !!up);
120}
121
122/* process rawmidi bytes and send events;
123 * we need no lock here for vmidi->event since it's handled only in this work
124 */
125static void snd_vmidi_output_work(struct work_struct *work)
126{
127	struct snd_virmidi *vmidi;
128	struct snd_rawmidi_substream *substream;
129	unsigned char input;
130	int ret;
131
132	vmidi = container_of(work, struct snd_virmidi, output_work);
133	substream = vmidi->substream;
134
135	/* discard the outputs in dispatch mode unless subscribed */
136	if (vmidi->seq_mode == SNDRV_VIRMIDI_SEQ_DISPATCH &&
137	    !(vmidi->rdev->flags & SNDRV_VIRMIDI_SUBSCRIBE)) {
138		snd_rawmidi_proceed(substream);
139		return;
140	}
141
142	while (READ_ONCE(vmidi->trigger)) {
143		if (snd_rawmidi_transmit(substream, &input, 1) != 1)
144			break;
145		if (!snd_midi_event_encode_byte(vmidi->parser, input,
146						&vmidi->event))
147			continue;
148		if (vmidi->event.type != SNDRV_SEQ_EVENT_NONE) {
149			ret = snd_seq_kernel_client_dispatch(vmidi->client,
150							     &vmidi->event,
151							     false, 0);
152			vmidi->event.type = SNDRV_SEQ_EVENT_NONE;
153			if (ret < 0)
154				break;
155		}
156		/* rawmidi input might be huge, allow to have a break */
157		cond_resched();
158	}
159}
160
161/*
162 * trigger rawmidi stream for output
163 */
164static void snd_virmidi_output_trigger(struct snd_rawmidi_substream *substream, int up)
165{
166	struct snd_virmidi *vmidi = substream->runtime->private_data;
 
 
167
168	WRITE_ONCE(vmidi->trigger, !!up);
169	if (up)
170		queue_work(system_highpri_wq, &vmidi->output_work);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
171}
172
173/*
174 * open rawmidi handle for input
175 */
176static int snd_virmidi_input_open(struct snd_rawmidi_substream *substream)
177{
178	struct snd_virmidi_dev *rdev = substream->rmidi->private_data;
179	struct snd_rawmidi_runtime *runtime = substream->runtime;
180	struct snd_virmidi *vmidi;
 
181
182	vmidi = kzalloc(sizeof(*vmidi), GFP_KERNEL);
183	if (vmidi == NULL)
184		return -ENOMEM;
185	vmidi->substream = substream;
186	if (snd_midi_event_new(0, &vmidi->parser) < 0) {
187		kfree(vmidi);
188		return -ENOMEM;
189	}
190	vmidi->seq_mode = rdev->seq_mode;
191	vmidi->client = rdev->client;
192	vmidi->port = rdev->port;	
193	runtime->private_data = vmidi;
194	down_write(&rdev->filelist_sem);
195	write_lock_irq(&rdev->filelist_lock);
196	list_add_tail(&vmidi->list, &rdev->filelist);
197	write_unlock_irq(&rdev->filelist_lock);
198	up_write(&rdev->filelist_sem);
199	vmidi->rdev = rdev;
200	return 0;
201}
202
203/*
204 * open rawmidi handle for output
205 */
206static int snd_virmidi_output_open(struct snd_rawmidi_substream *substream)
207{
208	struct snd_virmidi_dev *rdev = substream->rmidi->private_data;
209	struct snd_rawmidi_runtime *runtime = substream->runtime;
210	struct snd_virmidi *vmidi;
211
212	vmidi = kzalloc(sizeof(*vmidi), GFP_KERNEL);
213	if (vmidi == NULL)
214		return -ENOMEM;
215	vmidi->substream = substream;
216	if (snd_midi_event_new(MAX_MIDI_EVENT_BUF, &vmidi->parser) < 0) {
217		kfree(vmidi);
218		return -ENOMEM;
219	}
220	vmidi->seq_mode = rdev->seq_mode;
221	vmidi->client = rdev->client;
222	vmidi->port = rdev->port;
223	snd_virmidi_init_event(vmidi, &vmidi->event);
224	vmidi->rdev = rdev;
225	INIT_WORK(&vmidi->output_work, snd_vmidi_output_work);
226	runtime->private_data = vmidi;
227	return 0;
228}
229
230/*
231 * close rawmidi handle for input
232 */
233static int snd_virmidi_input_close(struct snd_rawmidi_substream *substream)
234{
235	struct snd_virmidi_dev *rdev = substream->rmidi->private_data;
236	struct snd_virmidi *vmidi = substream->runtime->private_data;
237
238	down_write(&rdev->filelist_sem);
239	write_lock_irq(&rdev->filelist_lock);
240	list_del(&vmidi->list);
241	write_unlock_irq(&rdev->filelist_lock);
242	up_write(&rdev->filelist_sem);
243	snd_midi_event_free(vmidi->parser);
 
244	substream->runtime->private_data = NULL;
245	kfree(vmidi);
246	return 0;
247}
248
249/*
250 * close rawmidi handle for output
251 */
252static int snd_virmidi_output_close(struct snd_rawmidi_substream *substream)
253{
254	struct snd_virmidi *vmidi = substream->runtime->private_data;
255
256	WRITE_ONCE(vmidi->trigger, false); /* to be sure */
257	cancel_work_sync(&vmidi->output_work);
258	snd_midi_event_free(vmidi->parser);
259	substream->runtime->private_data = NULL;
260	kfree(vmidi);
261	return 0;
262}
263
264/*
265 * subscribe callback - allow output to rawmidi device
266 */
267static int snd_virmidi_subscribe(void *private_data,
268				 struct snd_seq_port_subscribe *info)
269{
270	struct snd_virmidi_dev *rdev;
271
272	rdev = private_data;
273	if (!try_module_get(rdev->card->module))
274		return -EFAULT;
275	rdev->flags |= SNDRV_VIRMIDI_SUBSCRIBE;
276	return 0;
277}
278
279/*
280 * unsubscribe callback - disallow output to rawmidi device
281 */
282static int snd_virmidi_unsubscribe(void *private_data,
283				   struct snd_seq_port_subscribe *info)
284{
285	struct snd_virmidi_dev *rdev;
286
287	rdev = private_data;
288	rdev->flags &= ~SNDRV_VIRMIDI_SUBSCRIBE;
289	module_put(rdev->card->module);
290	return 0;
291}
292
293
294/*
295 * use callback - allow input to rawmidi device
296 */
297static int snd_virmidi_use(void *private_data,
298			   struct snd_seq_port_subscribe *info)
299{
300	struct snd_virmidi_dev *rdev;
301
302	rdev = private_data;
303	if (!try_module_get(rdev->card->module))
304		return -EFAULT;
305	rdev->flags |= SNDRV_VIRMIDI_USE;
306	return 0;
307}
308
309/*
310 * unuse callback - disallow input to rawmidi device
311 */
312static int snd_virmidi_unuse(void *private_data,
313			     struct snd_seq_port_subscribe *info)
314{
315	struct snd_virmidi_dev *rdev;
316
317	rdev = private_data;
318	rdev->flags &= ~SNDRV_VIRMIDI_USE;
319	module_put(rdev->card->module);
320	return 0;
321}
322
323
324/*
325 *  Register functions
326 */
327
328static const struct snd_rawmidi_ops snd_virmidi_input_ops = {
329	.open = snd_virmidi_input_open,
330	.close = snd_virmidi_input_close,
331	.trigger = snd_virmidi_input_trigger,
332};
333
334static const struct snd_rawmidi_ops snd_virmidi_output_ops = {
335	.open = snd_virmidi_output_open,
336	.close = snd_virmidi_output_close,
337	.trigger = snd_virmidi_output_trigger,
338};
339
340/*
341 * create a sequencer client and a port
342 */
343static int snd_virmidi_dev_attach_seq(struct snd_virmidi_dev *rdev)
344{
345	int client;
346	struct snd_seq_port_callback pcallbacks;
347	struct snd_seq_port_info *pinfo;
348	int err;
349
350	if (rdev->client >= 0)
351		return 0;
352
353	pinfo = kzalloc(sizeof(*pinfo), GFP_KERNEL);
354	if (!pinfo) {
355		err = -ENOMEM;
356		goto __error;
357	}
358
359	client = snd_seq_create_kernel_client(rdev->card, rdev->device,
360					      "%s %d-%d", rdev->rmidi->name,
361					      rdev->card->number,
362					      rdev->device);
363	if (client < 0) {
364		err = client;
365		goto __error;
366	}
367	rdev->client = client;
368
369	/* create a port */
370	pinfo->addr.client = client;
371	sprintf(pinfo->name, "VirMIDI %d-%d", rdev->card->number, rdev->device);
372	/* set all capabilities */
373	pinfo->capability |= SNDRV_SEQ_PORT_CAP_WRITE | SNDRV_SEQ_PORT_CAP_SYNC_WRITE | SNDRV_SEQ_PORT_CAP_SUBS_WRITE;
374	pinfo->capability |= SNDRV_SEQ_PORT_CAP_READ | SNDRV_SEQ_PORT_CAP_SYNC_READ | SNDRV_SEQ_PORT_CAP_SUBS_READ;
375	pinfo->capability |= SNDRV_SEQ_PORT_CAP_DUPLEX;
376	pinfo->type = SNDRV_SEQ_PORT_TYPE_MIDI_GENERIC
377		| SNDRV_SEQ_PORT_TYPE_SOFTWARE
378		| SNDRV_SEQ_PORT_TYPE_PORT;
379	pinfo->midi_channels = 16;
380	memset(&pcallbacks, 0, sizeof(pcallbacks));
381	pcallbacks.owner = THIS_MODULE;
382	pcallbacks.private_data = rdev;
383	pcallbacks.subscribe = snd_virmidi_subscribe;
384	pcallbacks.unsubscribe = snd_virmidi_unsubscribe;
385	pcallbacks.use = snd_virmidi_use;
386	pcallbacks.unuse = snd_virmidi_unuse;
387	pcallbacks.event_input = snd_virmidi_event_input;
388	pinfo->kernel = &pcallbacks;
389	err = snd_seq_kernel_client_ctl(client, SNDRV_SEQ_IOCTL_CREATE_PORT, pinfo);
390	if (err < 0) {
391		snd_seq_delete_kernel_client(client);
392		rdev->client = -1;
393		goto __error;
394	}
395
396	rdev->port = pinfo->addr.port;
397	err = 0; /* success */
398
399 __error:
400	kfree(pinfo);
401	return err;
402}
403
404
405/*
406 * release the sequencer client
407 */
408static void snd_virmidi_dev_detach_seq(struct snd_virmidi_dev *rdev)
409{
410	if (rdev->client >= 0) {
411		snd_seq_delete_kernel_client(rdev->client);
412		rdev->client = -1;
413	}
414}
415
416/*
417 * register the device
418 */
419static int snd_virmidi_dev_register(struct snd_rawmidi *rmidi)
420{
421	struct snd_virmidi_dev *rdev = rmidi->private_data;
422	int err;
423
424	switch (rdev->seq_mode) {
425	case SNDRV_VIRMIDI_SEQ_DISPATCH:
426		err = snd_virmidi_dev_attach_seq(rdev);
427		if (err < 0)
428			return err;
429		break;
430	case SNDRV_VIRMIDI_SEQ_ATTACH:
431		if (rdev->client == 0)
432			return -EINVAL;
433		/* should check presence of port more strictly.. */
434		break;
435	default:
436		pr_err("ALSA: seq_virmidi: seq_mode is not set: %d\n", rdev->seq_mode);
437		return -EINVAL;
438	}
439	return 0;
440}
441
442
443/*
444 * unregister the device
445 */
446static int snd_virmidi_dev_unregister(struct snd_rawmidi *rmidi)
447{
448	struct snd_virmidi_dev *rdev = rmidi->private_data;
449
450	if (rdev->seq_mode == SNDRV_VIRMIDI_SEQ_DISPATCH)
451		snd_virmidi_dev_detach_seq(rdev);
452	return 0;
453}
454
455/*
456 *
457 */
458static const struct snd_rawmidi_global_ops snd_virmidi_global_ops = {
459	.dev_register = snd_virmidi_dev_register,
460	.dev_unregister = snd_virmidi_dev_unregister,
461};
462
463/*
464 * free device
465 */
466static void snd_virmidi_free(struct snd_rawmidi *rmidi)
467{
468	struct snd_virmidi_dev *rdev = rmidi->private_data;
469	kfree(rdev);
470}
471
472/*
473 * create a new device
474 *
475 */
476/* exported */
477int snd_virmidi_new(struct snd_card *card, int device, struct snd_rawmidi **rrmidi)
478{
479	struct snd_rawmidi *rmidi;
480	struct snd_virmidi_dev *rdev;
481	int err;
482	
483	*rrmidi = NULL;
484	if ((err = snd_rawmidi_new(card, "VirMidi", device,
485				   16,	/* may be configurable */
486				   16,	/* may be configurable */
487				   &rmidi)) < 0)
488		return err;
489	strcpy(rmidi->name, rmidi->id);
490	rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
491	if (rdev == NULL) {
492		snd_device_free(card, rmidi);
493		return -ENOMEM;
494	}
495	rdev->card = card;
496	rdev->rmidi = rmidi;
497	rdev->device = device;
498	rdev->client = -1;
499	init_rwsem(&rdev->filelist_sem);
500	rwlock_init(&rdev->filelist_lock);
501	INIT_LIST_HEAD(&rdev->filelist);
502	rdev->seq_mode = SNDRV_VIRMIDI_SEQ_DISPATCH;
503	rmidi->private_data = rdev;
504	rmidi->private_free = snd_virmidi_free;
505	rmidi->ops = &snd_virmidi_global_ops;
506	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_virmidi_input_ops);
507	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &snd_virmidi_output_ops);
508	rmidi->info_flags = SNDRV_RAWMIDI_INFO_INPUT |
509			    SNDRV_RAWMIDI_INFO_OUTPUT |
510			    SNDRV_RAWMIDI_INFO_DUPLEX;
511	*rrmidi = rmidi;
512	return 0;
513}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
514EXPORT_SYMBOL(snd_virmidi_new);
v3.15
 
  1/*
  2 *  Virtual Raw MIDI client on Sequencer
  3 *
  4 *  Copyright (c) 2000 by Takashi Iwai <tiwai@suse.de>,
  5 *                        Jaroslav Kysela <perex@perex.cz>
  6 *
  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.
 11 *
 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.
 16 *
 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
 20 *
 21 */
 22
 23/*
 24 * Virtual Raw MIDI client
 25 *
 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.
 31 *
 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.
 35 *
 36 */
 37
 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>
 50
 51MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>");
 52MODULE_DESCRIPTION("Virtual Raw MIDI client on Sequencer");
 53MODULE_LICENSE("GPL");
 54
 55/*
 56 * initialize an event record
 57 */
 58static void snd_virmidi_init_event(struct snd_virmidi *vmidi,
 59				   struct snd_seq_event *ev)
 60{
 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;
 66		break;
 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;
 71		break;
 72	}
 73	ev->type = SNDRV_SEQ_EVENT_NONE;
 74}
 75
 76/*
 77 * decode input event and put to read buffer of each opened file
 78 */
 79static int snd_virmidi_dev_receive_event(struct snd_virmidi_dev *rdev,
 80					 struct snd_seq_event *ev)
 
 81{
 82	struct snd_virmidi *vmidi;
 83	unsigned char msg[4];
 84	int len;
 85
 86	read_lock(&rdev->filelist_lock);
 
 
 
 87	list_for_each_entry(vmidi, &rdev->filelist, list) {
 88		if (!vmidi->trigger)
 89			continue;
 90		if (ev->type == SNDRV_SEQ_EVENT_SYSEX) {
 91			if ((ev->flags & SNDRV_SEQ_EVENT_LENGTH_MASK) != SNDRV_SEQ_EVENT_LENGTH_VARIABLE)
 92				continue;
 93			snd_seq_dump_var_event(ev, (snd_seq_dump_func_t)snd_rawmidi_receive, vmidi->substream);
 94		} else {
 95			len = snd_midi_event_decode(vmidi->parser, msg, sizeof(msg), ev);
 96			if (len > 0)
 97				snd_rawmidi_receive(vmidi->substream, msg, len);
 98		}
 99	}
100	read_unlock(&rdev->filelist_lock);
 
 
 
101
102	return 0;
103}
104
105/*
106 * receive an event from the remote virmidi port
107 *
108 * for rawmidi inputs, you can call this function from the event
109 * handler of a remote port which is attached to the virmidi via
110 * SNDRV_VIRMIDI_SEQ_ATTACH.
111 */
112#if 0
113int snd_virmidi_receive(struct snd_rawmidi *rmidi, struct snd_seq_event *ev)
114{
115	struct snd_virmidi_dev *rdev;
116
117	rdev = rmidi->private_data;
118	return snd_virmidi_dev_receive_event(rdev, ev);
119}
120#endif  /*  0  */
121
122/*
123 * event handler of virmidi port
124 */
125static int snd_virmidi_event_input(struct snd_seq_event *ev, int direct,
126				   void *private_data, int atomic, int hop)
127{
128	struct snd_virmidi_dev *rdev;
129
130	rdev = private_data;
131	if (!(rdev->flags & SNDRV_VIRMIDI_USE))
132		return 0; /* ignored */
133	return snd_virmidi_dev_receive_event(rdev, ev);
134}
135
136/*
137 * trigger rawmidi stream for input
138 */
139static void snd_virmidi_input_trigger(struct snd_rawmidi_substream *substream, int up)
140{
141	struct snd_virmidi *vmidi = substream->runtime->private_data;
142
143	if (up) {
144		vmidi->trigger = 1;
145	} else {
146		vmidi->trigger = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
147	}
148}
149
150/*
151 * trigger rawmidi stream for output
152 */
153static void snd_virmidi_output_trigger(struct snd_rawmidi_substream *substream, int up)
154{
155	struct snd_virmidi *vmidi = substream->runtime->private_data;
156	int count, res;
157	unsigned char buf[32], *pbuf;
158
159	if (up) {
160		vmidi->trigger = 1;
161		if (vmidi->seq_mode == SNDRV_VIRMIDI_SEQ_DISPATCH &&
162		    !(vmidi->rdev->flags & SNDRV_VIRMIDI_SUBSCRIBE)) {
163			snd_rawmidi_transmit_ack(substream, substream->runtime->buffer_size - substream->runtime->avail);
164			return;		/* ignored */
165		}
166		if (vmidi->event.type != SNDRV_SEQ_EVENT_NONE) {
167			if (snd_seq_kernel_client_dispatch(vmidi->client, &vmidi->event, in_atomic(), 0) < 0)
168				return;
169			vmidi->event.type = SNDRV_SEQ_EVENT_NONE;
170		}
171		while (1) {
172			count = snd_rawmidi_transmit_peek(substream, buf, sizeof(buf));
173			if (count <= 0)
174				break;
175			pbuf = buf;
176			while (count > 0) {
177				res = snd_midi_event_encode(vmidi->parser, pbuf, count, &vmidi->event);
178				if (res < 0) {
179					snd_midi_event_reset_encode(vmidi->parser);
180					continue;
181				}
182				snd_rawmidi_transmit_ack(substream, res);
183				pbuf += res;
184				count -= res;
185				if (vmidi->event.type != SNDRV_SEQ_EVENT_NONE) {
186					if (snd_seq_kernel_client_dispatch(vmidi->client, &vmidi->event, in_atomic(), 0) < 0)
187						return;
188					vmidi->event.type = SNDRV_SEQ_EVENT_NONE;
189				}
190			}
191		}
192	} else {
193		vmidi->trigger = 0;
194	}
195}
196
197/*
198 * open rawmidi handle for input
199 */
200static int snd_virmidi_input_open(struct snd_rawmidi_substream *substream)
201{
202	struct snd_virmidi_dev *rdev = substream->rmidi->private_data;
203	struct snd_rawmidi_runtime *runtime = substream->runtime;
204	struct snd_virmidi *vmidi;
205	unsigned long flags;
206
207	vmidi = kzalloc(sizeof(*vmidi), GFP_KERNEL);
208	if (vmidi == NULL)
209		return -ENOMEM;
210	vmidi->substream = substream;
211	if (snd_midi_event_new(0, &vmidi->parser) < 0) {
212		kfree(vmidi);
213		return -ENOMEM;
214	}
215	vmidi->seq_mode = rdev->seq_mode;
216	vmidi->client = rdev->client;
217	vmidi->port = rdev->port;	
218	runtime->private_data = vmidi;
219	write_lock_irqsave(&rdev->filelist_lock, flags);
 
220	list_add_tail(&vmidi->list, &rdev->filelist);
221	write_unlock_irqrestore(&rdev->filelist_lock, flags);
 
222	vmidi->rdev = rdev;
223	return 0;
224}
225
226/*
227 * open rawmidi handle for output
228 */
229static int snd_virmidi_output_open(struct snd_rawmidi_substream *substream)
230{
231	struct snd_virmidi_dev *rdev = substream->rmidi->private_data;
232	struct snd_rawmidi_runtime *runtime = substream->runtime;
233	struct snd_virmidi *vmidi;
234
235	vmidi = kzalloc(sizeof(*vmidi), GFP_KERNEL);
236	if (vmidi == NULL)
237		return -ENOMEM;
238	vmidi->substream = substream;
239	if (snd_midi_event_new(MAX_MIDI_EVENT_BUF, &vmidi->parser) < 0) {
240		kfree(vmidi);
241		return -ENOMEM;
242	}
243	vmidi->seq_mode = rdev->seq_mode;
244	vmidi->client = rdev->client;
245	vmidi->port = rdev->port;
246	snd_virmidi_init_event(vmidi, &vmidi->event);
247	vmidi->rdev = rdev;
 
248	runtime->private_data = vmidi;
249	return 0;
250}
251
252/*
253 * close rawmidi handle for input
254 */
255static int snd_virmidi_input_close(struct snd_rawmidi_substream *substream)
256{
 
257	struct snd_virmidi *vmidi = substream->runtime->private_data;
 
 
 
 
 
 
258	snd_midi_event_free(vmidi->parser);
259	list_del(&vmidi->list);
260	substream->runtime->private_data = NULL;
261	kfree(vmidi);
262	return 0;
263}
264
265/*
266 * close rawmidi handle for output
267 */
268static int snd_virmidi_output_close(struct snd_rawmidi_substream *substream)
269{
270	struct snd_virmidi *vmidi = substream->runtime->private_data;
 
 
 
271	snd_midi_event_free(vmidi->parser);
272	substream->runtime->private_data = NULL;
273	kfree(vmidi);
274	return 0;
275}
276
277/*
278 * subscribe callback - allow output to rawmidi device
279 */
280static int snd_virmidi_subscribe(void *private_data,
281				 struct snd_seq_port_subscribe *info)
282{
283	struct snd_virmidi_dev *rdev;
284
285	rdev = private_data;
286	if (!try_module_get(rdev->card->module))
287		return -EFAULT;
288	rdev->flags |= SNDRV_VIRMIDI_SUBSCRIBE;
289	return 0;
290}
291
292/*
293 * unsubscribe callback - disallow output to rawmidi device
294 */
295static int snd_virmidi_unsubscribe(void *private_data,
296				   struct snd_seq_port_subscribe *info)
297{
298	struct snd_virmidi_dev *rdev;
299
300	rdev = private_data;
301	rdev->flags &= ~SNDRV_VIRMIDI_SUBSCRIBE;
302	module_put(rdev->card->module);
303	return 0;
304}
305
306
307/*
308 * use callback - allow input to rawmidi device
309 */
310static int snd_virmidi_use(void *private_data,
311			   struct snd_seq_port_subscribe *info)
312{
313	struct snd_virmidi_dev *rdev;
314
315	rdev = private_data;
316	if (!try_module_get(rdev->card->module))
317		return -EFAULT;
318	rdev->flags |= SNDRV_VIRMIDI_USE;
319	return 0;
320}
321
322/*
323 * unuse callback - disallow input to rawmidi device
324 */
325static int snd_virmidi_unuse(void *private_data,
326			     struct snd_seq_port_subscribe *info)
327{
328	struct snd_virmidi_dev *rdev;
329
330	rdev = private_data;
331	rdev->flags &= ~SNDRV_VIRMIDI_USE;
332	module_put(rdev->card->module);
333	return 0;
334}
335
336
337/*
338 *  Register functions
339 */
340
341static struct snd_rawmidi_ops snd_virmidi_input_ops = {
342	.open = snd_virmidi_input_open,
343	.close = snd_virmidi_input_close,
344	.trigger = snd_virmidi_input_trigger,
345};
346
347static struct snd_rawmidi_ops snd_virmidi_output_ops = {
348	.open = snd_virmidi_output_open,
349	.close = snd_virmidi_output_close,
350	.trigger = snd_virmidi_output_trigger,
351};
352
353/*
354 * create a sequencer client and a port
355 */
356static int snd_virmidi_dev_attach_seq(struct snd_virmidi_dev *rdev)
357{
358	int client;
359	struct snd_seq_port_callback pcallbacks;
360	struct snd_seq_port_info *pinfo;
361	int err;
362
363	if (rdev->client >= 0)
364		return 0;
365
366	pinfo = kzalloc(sizeof(*pinfo), GFP_KERNEL);
367	if (!pinfo) {
368		err = -ENOMEM;
369		goto __error;
370	}
371
372	client = snd_seq_create_kernel_client(rdev->card, rdev->device,
373					      "%s %d-%d", rdev->rmidi->name,
374					      rdev->card->number,
375					      rdev->device);
376	if (client < 0) {
377		err = client;
378		goto __error;
379	}
380	rdev->client = client;
381
382	/* create a port */
383	pinfo->addr.client = client;
384	sprintf(pinfo->name, "VirMIDI %d-%d", rdev->card->number, rdev->device);
385	/* set all capabilities */
386	pinfo->capability |= SNDRV_SEQ_PORT_CAP_WRITE | SNDRV_SEQ_PORT_CAP_SYNC_WRITE | SNDRV_SEQ_PORT_CAP_SUBS_WRITE;
387	pinfo->capability |= SNDRV_SEQ_PORT_CAP_READ | SNDRV_SEQ_PORT_CAP_SYNC_READ | SNDRV_SEQ_PORT_CAP_SUBS_READ;
388	pinfo->capability |= SNDRV_SEQ_PORT_CAP_DUPLEX;
389	pinfo->type = SNDRV_SEQ_PORT_TYPE_MIDI_GENERIC
390		| SNDRV_SEQ_PORT_TYPE_SOFTWARE
391		| SNDRV_SEQ_PORT_TYPE_PORT;
392	pinfo->midi_channels = 16;
393	memset(&pcallbacks, 0, sizeof(pcallbacks));
394	pcallbacks.owner = THIS_MODULE;
395	pcallbacks.private_data = rdev;
396	pcallbacks.subscribe = snd_virmidi_subscribe;
397	pcallbacks.unsubscribe = snd_virmidi_unsubscribe;
398	pcallbacks.use = snd_virmidi_use;
399	pcallbacks.unuse = snd_virmidi_unuse;
400	pcallbacks.event_input = snd_virmidi_event_input;
401	pinfo->kernel = &pcallbacks;
402	err = snd_seq_kernel_client_ctl(client, SNDRV_SEQ_IOCTL_CREATE_PORT, pinfo);
403	if (err < 0) {
404		snd_seq_delete_kernel_client(client);
405		rdev->client = -1;
406		goto __error;
407	}
408
409	rdev->port = pinfo->addr.port;
410	err = 0; /* success */
411
412 __error:
413	kfree(pinfo);
414	return err;
415}
416
417
418/*
419 * release the sequencer client
420 */
421static void snd_virmidi_dev_detach_seq(struct snd_virmidi_dev *rdev)
422{
423	if (rdev->client >= 0) {
424		snd_seq_delete_kernel_client(rdev->client);
425		rdev->client = -1;
426	}
427}
428
429/*
430 * register the device
431 */
432static int snd_virmidi_dev_register(struct snd_rawmidi *rmidi)
433{
434	struct snd_virmidi_dev *rdev = rmidi->private_data;
435	int err;
436
437	switch (rdev->seq_mode) {
438	case SNDRV_VIRMIDI_SEQ_DISPATCH:
439		err = snd_virmidi_dev_attach_seq(rdev);
440		if (err < 0)
441			return err;
442		break;
443	case SNDRV_VIRMIDI_SEQ_ATTACH:
444		if (rdev->client == 0)
445			return -EINVAL;
446		/* should check presence of port more strictly.. */
447		break;
448	default:
449		pr_err("ALSA: seq_virmidi: seq_mode is not set: %d\n", rdev->seq_mode);
450		return -EINVAL;
451	}
452	return 0;
453}
454
455
456/*
457 * unregister the device
458 */
459static int snd_virmidi_dev_unregister(struct snd_rawmidi *rmidi)
460{
461	struct snd_virmidi_dev *rdev = rmidi->private_data;
462
463	if (rdev->seq_mode == SNDRV_VIRMIDI_SEQ_DISPATCH)
464		snd_virmidi_dev_detach_seq(rdev);
465	return 0;
466}
467
468/*
469 *
470 */
471static struct snd_rawmidi_global_ops snd_virmidi_global_ops = {
472	.dev_register = snd_virmidi_dev_register,
473	.dev_unregister = snd_virmidi_dev_unregister,
474};
475
476/*
477 * free device
478 */
479static void snd_virmidi_free(struct snd_rawmidi *rmidi)
480{
481	struct snd_virmidi_dev *rdev = rmidi->private_data;
482	kfree(rdev);
483}
484
485/*
486 * create a new device
487 *
488 */
489/* exported */
490int snd_virmidi_new(struct snd_card *card, int device, struct snd_rawmidi **rrmidi)
491{
492	struct snd_rawmidi *rmidi;
493	struct snd_virmidi_dev *rdev;
494	int err;
495	
496	*rrmidi = NULL;
497	if ((err = snd_rawmidi_new(card, "VirMidi", device,
498				   16,	/* may be configurable */
499				   16,	/* may be configurable */
500				   &rmidi)) < 0)
501		return err;
502	strcpy(rmidi->name, rmidi->id);
503	rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
504	if (rdev == NULL) {
505		snd_device_free(card, rmidi);
506		return -ENOMEM;
507	}
508	rdev->card = card;
509	rdev->rmidi = rmidi;
510	rdev->device = device;
511	rdev->client = -1;
 
512	rwlock_init(&rdev->filelist_lock);
513	INIT_LIST_HEAD(&rdev->filelist);
514	rdev->seq_mode = SNDRV_VIRMIDI_SEQ_DISPATCH;
515	rmidi->private_data = rdev;
516	rmidi->private_free = snd_virmidi_free;
517	rmidi->ops = &snd_virmidi_global_ops;
518	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_virmidi_input_ops);
519	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &snd_virmidi_output_ops);
520	rmidi->info_flags = SNDRV_RAWMIDI_INFO_INPUT |
521			    SNDRV_RAWMIDI_INFO_OUTPUT |
522			    SNDRV_RAWMIDI_INFO_DUPLEX;
523	*rrmidi = rmidi;
524	return 0;
525}
526
527/*
528 *  ENTRY functions
529 */
530
531static int __init alsa_virmidi_init(void)
532{
533	return 0;
534}
535
536static void __exit alsa_virmidi_exit(void)
537{
538}
539
540module_init(alsa_virmidi_init)
541module_exit(alsa_virmidi_exit)
542
543EXPORT_SYMBOL(snd_virmidi_new);