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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);
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 bool atomic)
82{
83 struct snd_virmidi *vmidi;
84 unsigned char msg[4];
85 int len;
86
87 if (atomic)
88 read_lock(&rdev->filelist_lock);
89 else
90 down_read(&rdev->filelist_sem);
91 list_for_each_entry(vmidi, &rdev->filelist, list) {
92 if (!vmidi->trigger)
93 continue;
94 if (ev->type == SNDRV_SEQ_EVENT_SYSEX) {
95 if ((ev->flags & SNDRV_SEQ_EVENT_LENGTH_MASK) != SNDRV_SEQ_EVENT_LENGTH_VARIABLE)
96 continue;
97 snd_seq_dump_var_event(ev, (snd_seq_dump_func_t)snd_rawmidi_receive, vmidi->substream);
98 } else {
99 len = snd_midi_event_decode(vmidi->parser, msg, sizeof(msg), ev);
100 if (len > 0)
101 snd_rawmidi_receive(vmidi->substream, msg, len);
102 }
103 }
104 if (atomic)
105 read_unlock(&rdev->filelist_lock);
106 else
107 up_read(&rdev->filelist_sem);
108
109 return 0;
110}
111
112/*
113 * receive an event from the remote virmidi port
114 *
115 * for rawmidi inputs, you can call this function from the event
116 * handler of a remote port which is attached to the virmidi via
117 * SNDRV_VIRMIDI_SEQ_ATTACH.
118 */
119#if 0
120int snd_virmidi_receive(struct snd_rawmidi *rmidi, struct snd_seq_event *ev)
121{
122 struct snd_virmidi_dev *rdev;
123
124 rdev = rmidi->private_data;
125 return snd_virmidi_dev_receive_event(rdev, ev, true);
126}
127#endif /* 0 */
128
129/*
130 * event handler of virmidi port
131 */
132static int snd_virmidi_event_input(struct snd_seq_event *ev, int direct,
133 void *private_data, int atomic, int hop)
134{
135 struct snd_virmidi_dev *rdev;
136
137 rdev = private_data;
138 if (!(rdev->flags & SNDRV_VIRMIDI_USE))
139 return 0; /* ignored */
140 return snd_virmidi_dev_receive_event(rdev, ev, atomic);
141}
142
143/*
144 * trigger rawmidi stream for input
145 */
146static void snd_virmidi_input_trigger(struct snd_rawmidi_substream *substream, int up)
147{
148 struct snd_virmidi *vmidi = substream->runtime->private_data;
149
150 if (up) {
151 vmidi->trigger = 1;
152 } else {
153 vmidi->trigger = 0;
154 }
155}
156
157/*
158 * trigger rawmidi stream for output
159 */
160static void snd_virmidi_output_trigger(struct snd_rawmidi_substream *substream, int up)
161{
162 struct snd_virmidi *vmidi = substream->runtime->private_data;
163 int count, res;
164 unsigned char buf[32], *pbuf;
165 unsigned long flags;
166
167 if (up) {
168 vmidi->trigger = 1;
169 if (vmidi->seq_mode == SNDRV_VIRMIDI_SEQ_DISPATCH &&
170 !(vmidi->rdev->flags & SNDRV_VIRMIDI_SUBSCRIBE)) {
171 while (snd_rawmidi_transmit(substream, buf,
172 sizeof(buf)) > 0) {
173 /* ignored */
174 }
175 return;
176 }
177 spin_lock_irqsave(&substream->runtime->lock, flags);
178 if (vmidi->event.type != SNDRV_SEQ_EVENT_NONE) {
179 if (snd_seq_kernel_client_dispatch(vmidi->client, &vmidi->event, in_atomic(), 0) < 0)
180 goto out;
181 vmidi->event.type = SNDRV_SEQ_EVENT_NONE;
182 }
183 while (1) {
184 count = __snd_rawmidi_transmit_peek(substream, buf, sizeof(buf));
185 if (count <= 0)
186 break;
187 pbuf = buf;
188 while (count > 0) {
189 res = snd_midi_event_encode(vmidi->parser, pbuf, count, &vmidi->event);
190 if (res < 0) {
191 snd_midi_event_reset_encode(vmidi->parser);
192 continue;
193 }
194 __snd_rawmidi_transmit_ack(substream, res);
195 pbuf += res;
196 count -= res;
197 if (vmidi->event.type != SNDRV_SEQ_EVENT_NONE) {
198 if (snd_seq_kernel_client_dispatch(vmidi->client, &vmidi->event, in_atomic(), 0) < 0)
199 goto out;
200 vmidi->event.type = SNDRV_SEQ_EVENT_NONE;
201 }
202 }
203 }
204 out:
205 spin_unlock_irqrestore(&substream->runtime->lock, flags);
206 } else {
207 vmidi->trigger = 0;
208 }
209}
210
211/*
212 * open rawmidi handle for input
213 */
214static int snd_virmidi_input_open(struct snd_rawmidi_substream *substream)
215{
216 struct snd_virmidi_dev *rdev = substream->rmidi->private_data;
217 struct snd_rawmidi_runtime *runtime = substream->runtime;
218 struct snd_virmidi *vmidi;
219
220 vmidi = kzalloc(sizeof(*vmidi), GFP_KERNEL);
221 if (vmidi == NULL)
222 return -ENOMEM;
223 vmidi->substream = substream;
224 if (snd_midi_event_new(0, &vmidi->parser) < 0) {
225 kfree(vmidi);
226 return -ENOMEM;
227 }
228 vmidi->seq_mode = rdev->seq_mode;
229 vmidi->client = rdev->client;
230 vmidi->port = rdev->port;
231 runtime->private_data = vmidi;
232 down_write(&rdev->filelist_sem);
233 write_lock_irq(&rdev->filelist_lock);
234 list_add_tail(&vmidi->list, &rdev->filelist);
235 write_unlock_irq(&rdev->filelist_lock);
236 up_write(&rdev->filelist_sem);
237 vmidi->rdev = rdev;
238 return 0;
239}
240
241/*
242 * open rawmidi handle for output
243 */
244static int snd_virmidi_output_open(struct snd_rawmidi_substream *substream)
245{
246 struct snd_virmidi_dev *rdev = substream->rmidi->private_data;
247 struct snd_rawmidi_runtime *runtime = substream->runtime;
248 struct snd_virmidi *vmidi;
249
250 vmidi = kzalloc(sizeof(*vmidi), GFP_KERNEL);
251 if (vmidi == NULL)
252 return -ENOMEM;
253 vmidi->substream = substream;
254 if (snd_midi_event_new(MAX_MIDI_EVENT_BUF, &vmidi->parser) < 0) {
255 kfree(vmidi);
256 return -ENOMEM;
257 }
258 vmidi->seq_mode = rdev->seq_mode;
259 vmidi->client = rdev->client;
260 vmidi->port = rdev->port;
261 snd_virmidi_init_event(vmidi, &vmidi->event);
262 vmidi->rdev = rdev;
263 runtime->private_data = vmidi;
264 return 0;
265}
266
267/*
268 * close rawmidi handle for input
269 */
270static int snd_virmidi_input_close(struct snd_rawmidi_substream *substream)
271{
272 struct snd_virmidi_dev *rdev = substream->rmidi->private_data;
273 struct snd_virmidi *vmidi = substream->runtime->private_data;
274
275 down_write(&rdev->filelist_sem);
276 write_lock_irq(&rdev->filelist_lock);
277 list_del(&vmidi->list);
278 write_unlock_irq(&rdev->filelist_lock);
279 up_write(&rdev->filelist_sem);
280 snd_midi_event_free(vmidi->parser);
281 substream->runtime->private_data = NULL;
282 kfree(vmidi);
283 return 0;
284}
285
286/*
287 * close rawmidi handle for output
288 */
289static int snd_virmidi_output_close(struct snd_rawmidi_substream *substream)
290{
291 struct snd_virmidi *vmidi = substream->runtime->private_data;
292 snd_midi_event_free(vmidi->parser);
293 substream->runtime->private_data = NULL;
294 kfree(vmidi);
295 return 0;
296}
297
298/*
299 * subscribe callback - allow output to rawmidi device
300 */
301static int snd_virmidi_subscribe(void *private_data,
302 struct snd_seq_port_subscribe *info)
303{
304 struct snd_virmidi_dev *rdev;
305
306 rdev = private_data;
307 if (!try_module_get(rdev->card->module))
308 return -EFAULT;
309 rdev->flags |= SNDRV_VIRMIDI_SUBSCRIBE;
310 return 0;
311}
312
313/*
314 * unsubscribe callback - disallow output to rawmidi device
315 */
316static int snd_virmidi_unsubscribe(void *private_data,
317 struct snd_seq_port_subscribe *info)
318{
319 struct snd_virmidi_dev *rdev;
320
321 rdev = private_data;
322 rdev->flags &= ~SNDRV_VIRMIDI_SUBSCRIBE;
323 module_put(rdev->card->module);
324 return 0;
325}
326
327
328/*
329 * use callback - allow input to rawmidi device
330 */
331static int snd_virmidi_use(void *private_data,
332 struct snd_seq_port_subscribe *info)
333{
334 struct snd_virmidi_dev *rdev;
335
336 rdev = private_data;
337 if (!try_module_get(rdev->card->module))
338 return -EFAULT;
339 rdev->flags |= SNDRV_VIRMIDI_USE;
340 return 0;
341}
342
343/*
344 * unuse callback - disallow input to rawmidi device
345 */
346static int snd_virmidi_unuse(void *private_data,
347 struct snd_seq_port_subscribe *info)
348{
349 struct snd_virmidi_dev *rdev;
350
351 rdev = private_data;
352 rdev->flags &= ~SNDRV_VIRMIDI_USE;
353 module_put(rdev->card->module);
354 return 0;
355}
356
357
358/*
359 * Register functions
360 */
361
362static const struct snd_rawmidi_ops snd_virmidi_input_ops = {
363 .open = snd_virmidi_input_open,
364 .close = snd_virmidi_input_close,
365 .trigger = snd_virmidi_input_trigger,
366};
367
368static const struct snd_rawmidi_ops snd_virmidi_output_ops = {
369 .open = snd_virmidi_output_open,
370 .close = snd_virmidi_output_close,
371 .trigger = snd_virmidi_output_trigger,
372};
373
374/*
375 * create a sequencer client and a port
376 */
377static int snd_virmidi_dev_attach_seq(struct snd_virmidi_dev *rdev)
378{
379 int client;
380 struct snd_seq_port_callback pcallbacks;
381 struct snd_seq_port_info *pinfo;
382 int err;
383
384 if (rdev->client >= 0)
385 return 0;
386
387 pinfo = kzalloc(sizeof(*pinfo), GFP_KERNEL);
388 if (!pinfo) {
389 err = -ENOMEM;
390 goto __error;
391 }
392
393 client = snd_seq_create_kernel_client(rdev->card, rdev->device,
394 "%s %d-%d", rdev->rmidi->name,
395 rdev->card->number,
396 rdev->device);
397 if (client < 0) {
398 err = client;
399 goto __error;
400 }
401 rdev->client = client;
402
403 /* create a port */
404 pinfo->addr.client = client;
405 sprintf(pinfo->name, "VirMIDI %d-%d", rdev->card->number, rdev->device);
406 /* set all capabilities */
407 pinfo->capability |= SNDRV_SEQ_PORT_CAP_WRITE | SNDRV_SEQ_PORT_CAP_SYNC_WRITE | SNDRV_SEQ_PORT_CAP_SUBS_WRITE;
408 pinfo->capability |= SNDRV_SEQ_PORT_CAP_READ | SNDRV_SEQ_PORT_CAP_SYNC_READ | SNDRV_SEQ_PORT_CAP_SUBS_READ;
409 pinfo->capability |= SNDRV_SEQ_PORT_CAP_DUPLEX;
410 pinfo->type = SNDRV_SEQ_PORT_TYPE_MIDI_GENERIC
411 | SNDRV_SEQ_PORT_TYPE_SOFTWARE
412 | SNDRV_SEQ_PORT_TYPE_PORT;
413 pinfo->midi_channels = 16;
414 memset(&pcallbacks, 0, sizeof(pcallbacks));
415 pcallbacks.owner = THIS_MODULE;
416 pcallbacks.private_data = rdev;
417 pcallbacks.subscribe = snd_virmidi_subscribe;
418 pcallbacks.unsubscribe = snd_virmidi_unsubscribe;
419 pcallbacks.use = snd_virmidi_use;
420 pcallbacks.unuse = snd_virmidi_unuse;
421 pcallbacks.event_input = snd_virmidi_event_input;
422 pinfo->kernel = &pcallbacks;
423 err = snd_seq_kernel_client_ctl(client, SNDRV_SEQ_IOCTL_CREATE_PORT, pinfo);
424 if (err < 0) {
425 snd_seq_delete_kernel_client(client);
426 rdev->client = -1;
427 goto __error;
428 }
429
430 rdev->port = pinfo->addr.port;
431 err = 0; /* success */
432
433 __error:
434 kfree(pinfo);
435 return err;
436}
437
438
439/*
440 * release the sequencer client
441 */
442static void snd_virmidi_dev_detach_seq(struct snd_virmidi_dev *rdev)
443{
444 if (rdev->client >= 0) {
445 snd_seq_delete_kernel_client(rdev->client);
446 rdev->client = -1;
447 }
448}
449
450/*
451 * register the device
452 */
453static int snd_virmidi_dev_register(struct snd_rawmidi *rmidi)
454{
455 struct snd_virmidi_dev *rdev = rmidi->private_data;
456 int err;
457
458 switch (rdev->seq_mode) {
459 case SNDRV_VIRMIDI_SEQ_DISPATCH:
460 err = snd_virmidi_dev_attach_seq(rdev);
461 if (err < 0)
462 return err;
463 break;
464 case SNDRV_VIRMIDI_SEQ_ATTACH:
465 if (rdev->client == 0)
466 return -EINVAL;
467 /* should check presence of port more strictly.. */
468 break;
469 default:
470 pr_err("ALSA: seq_virmidi: seq_mode is not set: %d\n", rdev->seq_mode);
471 return -EINVAL;
472 }
473 return 0;
474}
475
476
477/*
478 * unregister the device
479 */
480static int snd_virmidi_dev_unregister(struct snd_rawmidi *rmidi)
481{
482 struct snd_virmidi_dev *rdev = rmidi->private_data;
483
484 if (rdev->seq_mode == SNDRV_VIRMIDI_SEQ_DISPATCH)
485 snd_virmidi_dev_detach_seq(rdev);
486 return 0;
487}
488
489/*
490 *
491 */
492static const struct snd_rawmidi_global_ops snd_virmidi_global_ops = {
493 .dev_register = snd_virmidi_dev_register,
494 .dev_unregister = snd_virmidi_dev_unregister,
495};
496
497/*
498 * free device
499 */
500static void snd_virmidi_free(struct snd_rawmidi *rmidi)
501{
502 struct snd_virmidi_dev *rdev = rmidi->private_data;
503 kfree(rdev);
504}
505
506/*
507 * create a new device
508 *
509 */
510/* exported */
511int snd_virmidi_new(struct snd_card *card, int device, struct snd_rawmidi **rrmidi)
512{
513 struct snd_rawmidi *rmidi;
514 struct snd_virmidi_dev *rdev;
515 int err;
516
517 *rrmidi = NULL;
518 if ((err = snd_rawmidi_new(card, "VirMidi", device,
519 16, /* may be configurable */
520 16, /* may be configurable */
521 &rmidi)) < 0)
522 return err;
523 strcpy(rmidi->name, rmidi->id);
524 rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
525 if (rdev == NULL) {
526 snd_device_free(card, rmidi);
527 return -ENOMEM;
528 }
529 rdev->card = card;
530 rdev->rmidi = rmidi;
531 rdev->device = device;
532 rdev->client = -1;
533 init_rwsem(&rdev->filelist_sem);
534 rwlock_init(&rdev->filelist_lock);
535 INIT_LIST_HEAD(&rdev->filelist);
536 rdev->seq_mode = SNDRV_VIRMIDI_SEQ_DISPATCH;
537 rmidi->private_data = rdev;
538 rmidi->private_free = snd_virmidi_free;
539 rmidi->ops = &snd_virmidi_global_ops;
540 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_virmidi_input_ops);
541 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &snd_virmidi_output_ops);
542 rmidi->info_flags = SNDRV_RAWMIDI_INFO_INPUT |
543 SNDRV_RAWMIDI_INFO_OUTPUT |
544 SNDRV_RAWMIDI_INFO_DUPLEX;
545 *rrmidi = rmidi;
546 return 0;
547}
548EXPORT_SYMBOL(snd_virmidi_new);
549
550/*
551 * ENTRY functions
552 */
553
554static int __init alsa_virmidi_init(void)
555{
556 return 0;
557}
558
559static void __exit alsa_virmidi_exit(void)
560{
561}
562
563module_init(alsa_virmidi_init)
564module_exit(alsa_virmidi_exit)