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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);
v4.10.11
 
  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	unsigned long flags;
159
160	if (up) {
161		vmidi->trigger = 1;
162		if (vmidi->seq_mode == SNDRV_VIRMIDI_SEQ_DISPATCH &&
163		    !(vmidi->rdev->flags & SNDRV_VIRMIDI_SUBSCRIBE)) {
164			while (snd_rawmidi_transmit(substream, buf,
165						    sizeof(buf)) > 0) {
166				/* ignored */
167			}
168			return;
169		}
170		if (vmidi->event.type != SNDRV_SEQ_EVENT_NONE) {
171			if (snd_seq_kernel_client_dispatch(vmidi->client, &vmidi->event, in_atomic(), 0) < 0)
172				return;
173			vmidi->event.type = SNDRV_SEQ_EVENT_NONE;
174		}
175		spin_lock_irqsave(&substream->runtime->lock, flags);
176		while (1) {
177			count = __snd_rawmidi_transmit_peek(substream, buf, sizeof(buf));
178			if (count <= 0)
179				break;
180			pbuf = buf;
181			while (count > 0) {
182				res = snd_midi_event_encode(vmidi->parser, pbuf, count, &vmidi->event);
183				if (res < 0) {
184					snd_midi_event_reset_encode(vmidi->parser);
185					continue;
186				}
187				__snd_rawmidi_transmit_ack(substream, res);
188				pbuf += res;
189				count -= res;
190				if (vmidi->event.type != SNDRV_SEQ_EVENT_NONE) {
191					if (snd_seq_kernel_client_dispatch(vmidi->client, &vmidi->event, in_atomic(), 0) < 0)
192						goto out;
193					vmidi->event.type = SNDRV_SEQ_EVENT_NONE;
194				}
195			}
196		}
197	out:
198		spin_unlock_irqrestore(&substream->runtime->lock, flags);
199	} else {
200		vmidi->trigger = 0;
201	}
202}
203
204/*
205 * open rawmidi handle for input
206 */
207static int snd_virmidi_input_open(struct snd_rawmidi_substream *substream)
208{
209	struct snd_virmidi_dev *rdev = substream->rmidi->private_data;
210	struct snd_rawmidi_runtime *runtime = substream->runtime;
211	struct snd_virmidi *vmidi;
212	unsigned long flags;
213
214	vmidi = kzalloc(sizeof(*vmidi), GFP_KERNEL);
215	if (vmidi == NULL)
216		return -ENOMEM;
217	vmidi->substream = substream;
218	if (snd_midi_event_new(0, &vmidi->parser) < 0) {
219		kfree(vmidi);
220		return -ENOMEM;
221	}
222	vmidi->seq_mode = rdev->seq_mode;
223	vmidi->client = rdev->client;
224	vmidi->port = rdev->port;	
225	runtime->private_data = vmidi;
226	write_lock_irqsave(&rdev->filelist_lock, flags);
 
227	list_add_tail(&vmidi->list, &rdev->filelist);
228	write_unlock_irqrestore(&rdev->filelist_lock, flags);
 
229	vmidi->rdev = rdev;
230	return 0;
231}
232
233/*
234 * open rawmidi handle for output
235 */
236static int snd_virmidi_output_open(struct snd_rawmidi_substream *substream)
237{
238	struct snd_virmidi_dev *rdev = substream->rmidi->private_data;
239	struct snd_rawmidi_runtime *runtime = substream->runtime;
240	struct snd_virmidi *vmidi;
241
242	vmidi = kzalloc(sizeof(*vmidi), GFP_KERNEL);
243	if (vmidi == NULL)
244		return -ENOMEM;
245	vmidi->substream = substream;
246	if (snd_midi_event_new(MAX_MIDI_EVENT_BUF, &vmidi->parser) < 0) {
247		kfree(vmidi);
248		return -ENOMEM;
249	}
250	vmidi->seq_mode = rdev->seq_mode;
251	vmidi->client = rdev->client;
252	vmidi->port = rdev->port;
253	snd_virmidi_init_event(vmidi, &vmidi->event);
254	vmidi->rdev = rdev;
 
255	runtime->private_data = vmidi;
256	return 0;
257}
258
259/*
260 * close rawmidi handle for input
261 */
262static int snd_virmidi_input_close(struct snd_rawmidi_substream *substream)
263{
264	struct snd_virmidi_dev *rdev = substream->rmidi->private_data;
265	struct snd_virmidi *vmidi = substream->runtime->private_data;
266
 
267	write_lock_irq(&rdev->filelist_lock);
268	list_del(&vmidi->list);
269	write_unlock_irq(&rdev->filelist_lock);
 
270	snd_midi_event_free(vmidi->parser);
271	substream->runtime->private_data = NULL;
272	kfree(vmidi);
273	return 0;
274}
275
276/*
277 * close rawmidi handle for output
278 */
279static int snd_virmidi_output_close(struct snd_rawmidi_substream *substream)
280{
281	struct snd_virmidi *vmidi = substream->runtime->private_data;
 
 
 
282	snd_midi_event_free(vmidi->parser);
283	substream->runtime->private_data = NULL;
284	kfree(vmidi);
285	return 0;
286}
287
288/*
289 * subscribe callback - allow output to rawmidi device
290 */
291static int snd_virmidi_subscribe(void *private_data,
292				 struct snd_seq_port_subscribe *info)
293{
294	struct snd_virmidi_dev *rdev;
295
296	rdev = private_data;
297	if (!try_module_get(rdev->card->module))
298		return -EFAULT;
299	rdev->flags |= SNDRV_VIRMIDI_SUBSCRIBE;
300	return 0;
301}
302
303/*
304 * unsubscribe callback - disallow output to rawmidi device
305 */
306static int snd_virmidi_unsubscribe(void *private_data,
307				   struct snd_seq_port_subscribe *info)
308{
309	struct snd_virmidi_dev *rdev;
310
311	rdev = private_data;
312	rdev->flags &= ~SNDRV_VIRMIDI_SUBSCRIBE;
313	module_put(rdev->card->module);
314	return 0;
315}
316
317
318/*
319 * use callback - allow input to rawmidi device
320 */
321static int snd_virmidi_use(void *private_data,
322			   struct snd_seq_port_subscribe *info)
323{
324	struct snd_virmidi_dev *rdev;
325
326	rdev = private_data;
327	if (!try_module_get(rdev->card->module))
328		return -EFAULT;
329	rdev->flags |= SNDRV_VIRMIDI_USE;
330	return 0;
331}
332
333/*
334 * unuse callback - disallow input to rawmidi device
335 */
336static int snd_virmidi_unuse(void *private_data,
337			     struct snd_seq_port_subscribe *info)
338{
339	struct snd_virmidi_dev *rdev;
340
341	rdev = private_data;
342	rdev->flags &= ~SNDRV_VIRMIDI_USE;
343	module_put(rdev->card->module);
344	return 0;
345}
346
347
348/*
349 *  Register functions
350 */
351
352static struct snd_rawmidi_ops snd_virmidi_input_ops = {
353	.open = snd_virmidi_input_open,
354	.close = snd_virmidi_input_close,
355	.trigger = snd_virmidi_input_trigger,
356};
357
358static struct snd_rawmidi_ops snd_virmidi_output_ops = {
359	.open = snd_virmidi_output_open,
360	.close = snd_virmidi_output_close,
361	.trigger = snd_virmidi_output_trigger,
362};
363
364/*
365 * create a sequencer client and a port
366 */
367static int snd_virmidi_dev_attach_seq(struct snd_virmidi_dev *rdev)
368{
369	int client;
370	struct snd_seq_port_callback pcallbacks;
371	struct snd_seq_port_info *pinfo;
372	int err;
373
374	if (rdev->client >= 0)
375		return 0;
376
377	pinfo = kzalloc(sizeof(*pinfo), GFP_KERNEL);
378	if (!pinfo) {
379		err = -ENOMEM;
380		goto __error;
381	}
382
383	client = snd_seq_create_kernel_client(rdev->card, rdev->device,
384					      "%s %d-%d", rdev->rmidi->name,
385					      rdev->card->number,
386					      rdev->device);
387	if (client < 0) {
388		err = client;
389		goto __error;
390	}
391	rdev->client = client;
392
393	/* create a port */
394	pinfo->addr.client = client;
395	sprintf(pinfo->name, "VirMIDI %d-%d", rdev->card->number, rdev->device);
396	/* set all capabilities */
397	pinfo->capability |= SNDRV_SEQ_PORT_CAP_WRITE | SNDRV_SEQ_PORT_CAP_SYNC_WRITE | SNDRV_SEQ_PORT_CAP_SUBS_WRITE;
398	pinfo->capability |= SNDRV_SEQ_PORT_CAP_READ | SNDRV_SEQ_PORT_CAP_SYNC_READ | SNDRV_SEQ_PORT_CAP_SUBS_READ;
399	pinfo->capability |= SNDRV_SEQ_PORT_CAP_DUPLEX;
400	pinfo->type = SNDRV_SEQ_PORT_TYPE_MIDI_GENERIC
401		| SNDRV_SEQ_PORT_TYPE_SOFTWARE
402		| SNDRV_SEQ_PORT_TYPE_PORT;
403	pinfo->midi_channels = 16;
404	memset(&pcallbacks, 0, sizeof(pcallbacks));
405	pcallbacks.owner = THIS_MODULE;
406	pcallbacks.private_data = rdev;
407	pcallbacks.subscribe = snd_virmidi_subscribe;
408	pcallbacks.unsubscribe = snd_virmidi_unsubscribe;
409	pcallbacks.use = snd_virmidi_use;
410	pcallbacks.unuse = snd_virmidi_unuse;
411	pcallbacks.event_input = snd_virmidi_event_input;
412	pinfo->kernel = &pcallbacks;
413	err = snd_seq_kernel_client_ctl(client, SNDRV_SEQ_IOCTL_CREATE_PORT, pinfo);
414	if (err < 0) {
415		snd_seq_delete_kernel_client(client);
416		rdev->client = -1;
417		goto __error;
418	}
419
420	rdev->port = pinfo->addr.port;
421	err = 0; /* success */
422
423 __error:
424	kfree(pinfo);
425	return err;
426}
427
428
429/*
430 * release the sequencer client
431 */
432static void snd_virmidi_dev_detach_seq(struct snd_virmidi_dev *rdev)
433{
434	if (rdev->client >= 0) {
435		snd_seq_delete_kernel_client(rdev->client);
436		rdev->client = -1;
437	}
438}
439
440/*
441 * register the device
442 */
443static int snd_virmidi_dev_register(struct snd_rawmidi *rmidi)
444{
445	struct snd_virmidi_dev *rdev = rmidi->private_data;
446	int err;
447
448	switch (rdev->seq_mode) {
449	case SNDRV_VIRMIDI_SEQ_DISPATCH:
450		err = snd_virmidi_dev_attach_seq(rdev);
451		if (err < 0)
452			return err;
453		break;
454	case SNDRV_VIRMIDI_SEQ_ATTACH:
455		if (rdev->client == 0)
456			return -EINVAL;
457		/* should check presence of port more strictly.. */
458		break;
459	default:
460		pr_err("ALSA: seq_virmidi: seq_mode is not set: %d\n", rdev->seq_mode);
461		return -EINVAL;
462	}
463	return 0;
464}
465
466
467/*
468 * unregister the device
469 */
470static int snd_virmidi_dev_unregister(struct snd_rawmidi *rmidi)
471{
472	struct snd_virmidi_dev *rdev = rmidi->private_data;
473
474	if (rdev->seq_mode == SNDRV_VIRMIDI_SEQ_DISPATCH)
475		snd_virmidi_dev_detach_seq(rdev);
476	return 0;
477}
478
479/*
480 *
481 */
482static const struct snd_rawmidi_global_ops snd_virmidi_global_ops = {
483	.dev_register = snd_virmidi_dev_register,
484	.dev_unregister = snd_virmidi_dev_unregister,
485};
486
487/*
488 * free device
489 */
490static void snd_virmidi_free(struct snd_rawmidi *rmidi)
491{
492	struct snd_virmidi_dev *rdev = rmidi->private_data;
493	kfree(rdev);
494}
495
496/*
497 * create a new device
498 *
499 */
500/* exported */
501int snd_virmidi_new(struct snd_card *card, int device, struct snd_rawmidi **rrmidi)
502{
503	struct snd_rawmidi *rmidi;
504	struct snd_virmidi_dev *rdev;
505	int err;
506	
507	*rrmidi = NULL;
508	if ((err = snd_rawmidi_new(card, "VirMidi", device,
509				   16,	/* may be configurable */
510				   16,	/* may be configurable */
511				   &rmidi)) < 0)
512		return err;
513	strcpy(rmidi->name, rmidi->id);
514	rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
515	if (rdev == NULL) {
516		snd_device_free(card, rmidi);
517		return -ENOMEM;
518	}
519	rdev->card = card;
520	rdev->rmidi = rmidi;
521	rdev->device = device;
522	rdev->client = -1;
 
523	rwlock_init(&rdev->filelist_lock);
524	INIT_LIST_HEAD(&rdev->filelist);
525	rdev->seq_mode = SNDRV_VIRMIDI_SEQ_DISPATCH;
526	rmidi->private_data = rdev;
527	rmidi->private_free = snd_virmidi_free;
528	rmidi->ops = &snd_virmidi_global_ops;
529	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_virmidi_input_ops);
530	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &snd_virmidi_output_ops);
531	rmidi->info_flags = SNDRV_RAWMIDI_INFO_INPUT |
532			    SNDRV_RAWMIDI_INFO_OUTPUT |
533			    SNDRV_RAWMIDI_INFO_DUPLEX;
534	*rrmidi = rmidi;
535	return 0;
536}
537
538/*
539 *  ENTRY functions
540 */
541
542static int __init alsa_virmidi_init(void)
543{
544	return 0;
545}
546
547static void __exit alsa_virmidi_exit(void)
548{
549}
550
551module_init(alsa_virmidi_init)
552module_exit(alsa_virmidi_exit)
553
554EXPORT_SYMBOL(snd_virmidi_new);