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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// 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 snd_midi_event_reset_decode(vmidi->parser);
85 } else {
86 len = snd_midi_event_decode(vmidi->parser, msg, sizeof(msg), ev);
87 if (len > 0)
88 snd_rawmidi_receive(vmidi->substream, msg, len);
89 }
90 }
91 if (atomic)
92 read_unlock(&rdev->filelist_lock);
93 else
94 up_read(&rdev->filelist_sem);
95
96 return 0;
97}
98
99/*
100 * event handler of virmidi port
101 */
102static int snd_virmidi_event_input(struct snd_seq_event *ev, int direct,
103 void *private_data, int atomic, int hop)
104{
105 struct snd_virmidi_dev *rdev;
106
107 rdev = private_data;
108 if (!(rdev->flags & SNDRV_VIRMIDI_USE))
109 return 0; /* ignored */
110 return snd_virmidi_dev_receive_event(rdev, ev, atomic);
111}
112
113/*
114 * trigger rawmidi stream for input
115 */
116static void snd_virmidi_input_trigger(struct snd_rawmidi_substream *substream, int up)
117{
118 struct snd_virmidi *vmidi = substream->runtime->private_data;
119
120 WRITE_ONCE(vmidi->trigger, !!up);
121}
122
123/* process rawmidi bytes and send events;
124 * we need no lock here for vmidi->event since it's handled only in this work
125 */
126static void snd_vmidi_output_work(struct work_struct *work)
127{
128 struct snd_virmidi *vmidi;
129 struct snd_rawmidi_substream *substream;
130 unsigned char input;
131 int ret;
132
133 vmidi = container_of(work, struct snd_virmidi, output_work);
134 substream = vmidi->substream;
135
136 /* discard the outputs in dispatch mode unless subscribed */
137 if (vmidi->seq_mode == SNDRV_VIRMIDI_SEQ_DISPATCH &&
138 !(vmidi->rdev->flags & SNDRV_VIRMIDI_SUBSCRIBE)) {
139 snd_rawmidi_proceed(substream);
140 return;
141 }
142
143 while (READ_ONCE(vmidi->trigger)) {
144 if (snd_rawmidi_transmit(substream, &input, 1) != 1)
145 break;
146 if (!snd_midi_event_encode_byte(vmidi->parser, input,
147 &vmidi->event))
148 continue;
149 if (vmidi->event.type != SNDRV_SEQ_EVENT_NONE) {
150 ret = snd_seq_kernel_client_dispatch(vmidi->client,
151 &vmidi->event,
152 false, 0);
153 vmidi->event.type = SNDRV_SEQ_EVENT_NONE;
154 if (ret < 0)
155 break;
156 }
157 /* rawmidi input might be huge, allow to have a break */
158 cond_resched();
159 }
160}
161
162/*
163 * trigger rawmidi stream for output
164 */
165static void snd_virmidi_output_trigger(struct snd_rawmidi_substream *substream, int up)
166{
167 struct snd_virmidi *vmidi = substream->runtime->private_data;
168
169 WRITE_ONCE(vmidi->trigger, !!up);
170 if (up)
171 queue_work(system_highpri_wq, &vmidi->output_work);
172}
173
174/*
175 * open rawmidi handle for input
176 */
177static int snd_virmidi_input_open(struct snd_rawmidi_substream *substream)
178{
179 struct snd_virmidi_dev *rdev = substream->rmidi->private_data;
180 struct snd_rawmidi_runtime *runtime = substream->runtime;
181 struct snd_virmidi *vmidi;
182
183 vmidi = kzalloc(sizeof(*vmidi), GFP_KERNEL);
184 if (vmidi == NULL)
185 return -ENOMEM;
186 vmidi->substream = substream;
187 if (snd_midi_event_new(0, &vmidi->parser) < 0) {
188 kfree(vmidi);
189 return -ENOMEM;
190 }
191 vmidi->seq_mode = rdev->seq_mode;
192 vmidi->client = rdev->client;
193 vmidi->port = rdev->port;
194 runtime->private_data = vmidi;
195 down_write(&rdev->filelist_sem);
196 write_lock_irq(&rdev->filelist_lock);
197 list_add_tail(&vmidi->list, &rdev->filelist);
198 write_unlock_irq(&rdev->filelist_lock);
199 up_write(&rdev->filelist_sem);
200 vmidi->rdev = rdev;
201 return 0;
202}
203
204/*
205 * open rawmidi handle for output
206 */
207static int snd_virmidi_output_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
213 vmidi = kzalloc(sizeof(*vmidi), GFP_KERNEL);
214 if (vmidi == NULL)
215 return -ENOMEM;
216 vmidi->substream = substream;
217 if (snd_midi_event_new(MAX_MIDI_EVENT_BUF, &vmidi->parser) < 0) {
218 kfree(vmidi);
219 return -ENOMEM;
220 }
221 vmidi->seq_mode = rdev->seq_mode;
222 vmidi->client = rdev->client;
223 vmidi->port = rdev->port;
224 snd_virmidi_init_event(vmidi, &vmidi->event);
225 vmidi->rdev = rdev;
226 INIT_WORK(&vmidi->output_work, snd_vmidi_output_work);
227 runtime->private_data = vmidi;
228 return 0;
229}
230
231/*
232 * close rawmidi handle for input
233 */
234static int snd_virmidi_input_close(struct snd_rawmidi_substream *substream)
235{
236 struct snd_virmidi_dev *rdev = substream->rmidi->private_data;
237 struct snd_virmidi *vmidi = substream->runtime->private_data;
238
239 down_write(&rdev->filelist_sem);
240 write_lock_irq(&rdev->filelist_lock);
241 list_del(&vmidi->list);
242 write_unlock_irq(&rdev->filelist_lock);
243 up_write(&rdev->filelist_sem);
244 snd_midi_event_free(vmidi->parser);
245 substream->runtime->private_data = NULL;
246 kfree(vmidi);
247 return 0;
248}
249
250/*
251 * close rawmidi handle for output
252 */
253static int snd_virmidi_output_close(struct snd_rawmidi_substream *substream)
254{
255 struct snd_virmidi *vmidi = substream->runtime->private_data;
256
257 WRITE_ONCE(vmidi->trigger, false); /* to be sure */
258 cancel_work_sync(&vmidi->output_work);
259 snd_midi_event_free(vmidi->parser);
260 substream->runtime->private_data = NULL;
261 kfree(vmidi);
262 return 0;
263}
264
265/*
266 * drain output work queue
267 */
268static void snd_virmidi_output_drain(struct snd_rawmidi_substream *substream)
269{
270 struct snd_virmidi *vmidi = substream->runtime->private_data;
271
272 flush_work(&vmidi->output_work);
273}
274
275/*
276 * subscribe callback - allow output to rawmidi device
277 */
278static int snd_virmidi_subscribe(void *private_data,
279 struct snd_seq_port_subscribe *info)
280{
281 struct snd_virmidi_dev *rdev;
282
283 rdev = private_data;
284 if (!try_module_get(rdev->card->module))
285 return -EFAULT;
286 rdev->flags |= SNDRV_VIRMIDI_SUBSCRIBE;
287 return 0;
288}
289
290/*
291 * unsubscribe callback - disallow output to rawmidi device
292 */
293static int snd_virmidi_unsubscribe(void *private_data,
294 struct snd_seq_port_subscribe *info)
295{
296 struct snd_virmidi_dev *rdev;
297
298 rdev = private_data;
299 rdev->flags &= ~SNDRV_VIRMIDI_SUBSCRIBE;
300 module_put(rdev->card->module);
301 return 0;
302}
303
304
305/*
306 * use callback - allow input to rawmidi device
307 */
308static int snd_virmidi_use(void *private_data,
309 struct snd_seq_port_subscribe *info)
310{
311 struct snd_virmidi_dev *rdev;
312
313 rdev = private_data;
314 if (!try_module_get(rdev->card->module))
315 return -EFAULT;
316 rdev->flags |= SNDRV_VIRMIDI_USE;
317 return 0;
318}
319
320/*
321 * unuse callback - disallow input to rawmidi device
322 */
323static int snd_virmidi_unuse(void *private_data,
324 struct snd_seq_port_subscribe *info)
325{
326 struct snd_virmidi_dev *rdev;
327
328 rdev = private_data;
329 rdev->flags &= ~SNDRV_VIRMIDI_USE;
330 module_put(rdev->card->module);
331 return 0;
332}
333
334
335/*
336 * Register functions
337 */
338
339static const struct snd_rawmidi_ops snd_virmidi_input_ops = {
340 .open = snd_virmidi_input_open,
341 .close = snd_virmidi_input_close,
342 .trigger = snd_virmidi_input_trigger,
343};
344
345static const struct snd_rawmidi_ops snd_virmidi_output_ops = {
346 .open = snd_virmidi_output_open,
347 .close = snd_virmidi_output_close,
348 .trigger = snd_virmidi_output_trigger,
349 .drain = snd_virmidi_output_drain,
350};
351
352/*
353 * create a sequencer client and a port
354 */
355static int snd_virmidi_dev_attach_seq(struct snd_virmidi_dev *rdev)
356{
357 int client;
358 struct snd_seq_port_callback pcallbacks;
359 struct snd_seq_port_info *pinfo;
360 int err;
361
362 if (rdev->client >= 0)
363 return 0;
364
365 pinfo = kzalloc(sizeof(*pinfo), GFP_KERNEL);
366 if (!pinfo) {
367 err = -ENOMEM;
368 goto __error;
369 }
370
371 client = snd_seq_create_kernel_client(rdev->card, rdev->device,
372 "%s %d-%d", rdev->rmidi->name,
373 rdev->card->number,
374 rdev->device);
375 if (client < 0) {
376 err = client;
377 goto __error;
378 }
379 rdev->client = client;
380
381 /* create a port */
382 pinfo->addr.client = client;
383 sprintf(pinfo->name, "VirMIDI %d-%d", rdev->card->number, rdev->device);
384 /* set all capabilities */
385 pinfo->capability |= SNDRV_SEQ_PORT_CAP_WRITE | SNDRV_SEQ_PORT_CAP_SYNC_WRITE | SNDRV_SEQ_PORT_CAP_SUBS_WRITE;
386 pinfo->capability |= SNDRV_SEQ_PORT_CAP_READ | SNDRV_SEQ_PORT_CAP_SYNC_READ | SNDRV_SEQ_PORT_CAP_SUBS_READ;
387 pinfo->capability |= SNDRV_SEQ_PORT_CAP_DUPLEX;
388 pinfo->direction = SNDRV_SEQ_PORT_DIR_BIDIRECTION;
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 const 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 err = snd_rawmidi_new(card, "VirMidi", device,
498 16, /* may be configurable */
499 16, /* may be configurable */
500 &rmidi);
501 if (err < 0)
502 return err;
503 strcpy(rmidi->name, rmidi->id);
504 rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
505 if (rdev == NULL) {
506 snd_device_free(card, rmidi);
507 return -ENOMEM;
508 }
509 rdev->card = card;
510 rdev->rmidi = rmidi;
511 rdev->device = device;
512 rdev->client = -1;
513 init_rwsem(&rdev->filelist_sem);
514 rwlock_init(&rdev->filelist_lock);
515 INIT_LIST_HEAD(&rdev->filelist);
516 rdev->seq_mode = SNDRV_VIRMIDI_SEQ_DISPATCH;
517 rmidi->private_data = rdev;
518 rmidi->private_free = snd_virmidi_free;
519 rmidi->ops = &snd_virmidi_global_ops;
520 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_virmidi_input_ops);
521 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &snd_virmidi_output_ops);
522 rmidi->info_flags = SNDRV_RAWMIDI_INFO_INPUT |
523 SNDRV_RAWMIDI_INFO_OUTPUT |
524 SNDRV_RAWMIDI_INFO_DUPLEX;
525 *rrmidi = rmidi;
526 return 0;
527}
528EXPORT_SYMBOL(snd_virmidi_new);