1 /*
2 * Generic MIDI synth driver for ALSA sequencer
3 * Copyright (c) 1998 by Frank van de Pol <fvdpol@coil.demon.nl>
4 * Jaroslav Kysela <perex@perex.cz>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 *
20 */
21
22 /*
23 Possible options for midisynth module:
24 - automatic opening of midi ports on first received event or subscription
25 (close will be performed when client leaves)
26 */
27
28
29 #include <linux/init.h>
30 #include <linux/slab.h>
31 #include <linux/errno.h>
32 #include <linux/string.h>
33 #include <linux/moduleparam.h>
34 #include <linux/mutex.h>
35 #include <sound/core.h>
36 #include <sound/rawmidi.h>
37 #include <sound/seq_kernel.h>
38 #include <sound/seq_device.h>
39 #include <sound/seq_midi_event.h>
40 #include <sound/initval.h>
41
42 MODULE_AUTHOR("Frank van de Pol <fvdpol@coil.demon.nl>, Jaroslav Kysela <perex@perex.cz>");
43 MODULE_DESCRIPTION("Advanced Linux Sound Architecture sequencer MIDI synth.");
44 MODULE_LICENSE("GPL");
45 static int output_buffer_size = PAGE_SIZE;
46 module_param(output_buffer_size, int, 0644);
47 MODULE_PARM_DESC(output_buffer_size, "Output buffer size in bytes.");
48 static int input_buffer_size = PAGE_SIZE;
49 module_param(input_buffer_size, int, 0644);
50 MODULE_PARM_DESC(input_buffer_size, "Input buffer size in bytes.");
51
52 /* data for this midi synth driver */
53 struct seq_midisynth {
54 struct snd_card *card;
55 int device;
56 int subdevice;
57 struct snd_rawmidi_file input_rfile;
58 struct snd_rawmidi_file output_rfile;
59 int seq_client;
60 int seq_port;
61 struct snd_midi_event *parser;
62 };
63
64 struct seq_midisynth_client {
65 int seq_client;
66 int num_ports;
67 int ports_per_device[SNDRV_RAWMIDI_DEVICES];
68 struct seq_midisynth *ports[SNDRV_RAWMIDI_DEVICES];
69 };
70
71 static struct seq_midisynth_client *synths[SNDRV_CARDS];
72 static DEFINE_MUTEX(register_mutex);
73
74 /* handle rawmidi input event (MIDI v1.0 stream) */
75 static void snd_midi_input_event(struct snd_rawmidi_substream *substream)
76 {
77 struct snd_rawmidi_runtime *runtime;
78 struct seq_midisynth *msynth;
79 struct snd_seq_event ev;
80 char buf[16], *pbuf;
81 long res, count;
82
83 if (substream == NULL)
84 return;
85 runtime = substream->runtime;
86 msynth = runtime->private_data;
87 if (msynth == NULL)
88 return;
89 memset(&ev, 0, sizeof(ev));
90 while (runtime->avail > 0) {
91 res = snd_rawmidi_kernel_read(substream, buf, sizeof(buf));
92 if (res <= 0)
93 continue;
94 if (msynth->parser == NULL)
95 continue;
96 pbuf = buf;
97 while (res > 0) {
98 count = snd_midi_event_encode(msynth->parser, pbuf, res, &ev);
99 if (count < 0)
100 break;
101 pbuf += count;
102 res -= count;
103 if (ev.type != SNDRV_SEQ_EVENT_NONE) {
104 ev.source.port = msynth->seq_port;
105 ev.dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS;
106 snd_seq_kernel_client_dispatch(msynth->seq_client, &ev, 1, 0);
107 /* clear event and reset header */
108 memset(&ev, 0, sizeof(ev));
109 }
110 }
111 }
112 }
113
114 static int dump_midi(struct snd_rawmidi_substream *substream, const char *buf, int count)
115 {
116 struct snd_rawmidi_runtime *runtime;
117 int tmp;
118
119 if (snd_BUG_ON(!substream || !buf))
120 return -EINVAL;
121 runtime = substream->runtime;
122 if ((tmp = runtime->avail) < count) {
123 snd_printd("warning, output event was lost (count = %i, available = %i)\n", count, tmp);
124 return -ENOMEM;
125 }
126 if (snd_rawmidi_kernel_write(substream, buf, count) < count)
127 return -EINVAL;
128 return 0;
129 }
130
131 static int event_process_midi(struct snd_seq_event *ev, int direct,
132 void *private_data, int atomic, int hop)
133 {
134 struct seq_midisynth *msynth = private_data;
135 unsigned char msg[10]; /* buffer for constructing midi messages */
136 struct snd_rawmidi_substream *substream;
137 int len;
138
139 if (snd_BUG_ON(!msynth))
140 return -EINVAL;
141 substream = msynth->output_rfile.output;
142 if (substream == NULL)
143 return -ENODEV;
144 if (ev->type == SNDRV_SEQ_EVENT_SYSEX) { /* special case, to save space */
145 if ((ev->flags & SNDRV_SEQ_EVENT_LENGTH_MASK) != SNDRV_SEQ_EVENT_LENGTH_VARIABLE) {
146 /* invalid event */
147 snd_printd("seq_midi: invalid sysex event flags = 0x%x\n", ev->flags);
148 return 0;
149 }
150 snd_seq_dump_var_event(ev, (snd_seq_dump_func_t)dump_midi, substream);
151 snd_midi_event_reset_decode(msynth->parser);
152 } else {
153 if (msynth->parser == NULL)
154 return -EIO;
155 len = snd_midi_event_decode(msynth->parser, msg, sizeof(msg), ev);
156 if (len < 0)
157 return 0;
158 if (dump_midi(substream, msg, len) < 0)
159 snd_midi_event_reset_decode(msynth->parser);
160 }
161 return 0;
162 }
163
164
165 static int snd_seq_midisynth_new(struct seq_midisynth *msynth,
166 struct snd_card *card,
167 int device,
168 int subdevice)
169 {
170 if (snd_midi_event_new(MAX_MIDI_EVENT_BUF, &msynth->parser) < 0)
171 return -ENOMEM;
172 msynth->card = card;
173 msynth->device = device;
174 msynth->subdevice = subdevice;
175 return 0;
176 }
177
178 /* open associated midi device for input */
179 static int midisynth_subscribe(void *private_data, struct snd_seq_port_subscribe *info)
180 {
181 int err;
182 struct seq_midisynth *msynth = private_data;
183 struct snd_rawmidi_runtime *runtime;
184 struct snd_rawmidi_params params;
185
186 /* open midi port */
187 if ((err = snd_rawmidi_kernel_open(msynth->card, msynth->device,
188 msynth->subdevice,
189 SNDRV_RAWMIDI_LFLG_INPUT,
190 &msynth->input_rfile)) < 0) {
191 snd_printd("midi input open failed!!!\n");
192 return err;
193 }
194 runtime = msynth->input_rfile.input->runtime;
195 memset(¶ms, 0, sizeof(params));
196 params.avail_min = 1;
197 params.buffer_size = input_buffer_size;
198 if ((err = snd_rawmidi_input_params(msynth->input_rfile.input, ¶ms)) < 0) {
199 snd_rawmidi_kernel_release(&msynth->input_rfile);
200 return err;
201 }
202 snd_midi_event_reset_encode(msynth->parser);
203 runtime->event = snd_midi_input_event;
204 runtime->private_data = msynth;
205 snd_rawmidi_kernel_read(msynth->input_rfile.input, NULL, 0);
206 return 0;
207 }
208
209 /* close associated midi device for input */
210 static int midisynth_unsubscribe(void *private_data, struct snd_seq_port_subscribe *info)
211 {
212 int err;
213 struct seq_midisynth *msynth = private_data;
214
215 if (snd_BUG_ON(!msynth->input_rfile.input))
216 return -EINVAL;
217 err = snd_rawmidi_kernel_release(&msynth->input_rfile);
218 return err;
219 }
220
221 /* open associated midi device for output */
222 static int midisynth_use(void *private_data, struct snd_seq_port_subscribe *info)
223 {
224 int err;
225 struct seq_midisynth *msynth = private_data;
226 struct snd_rawmidi_params params;
227
228 /* open midi port */
229 if ((err = snd_rawmidi_kernel_open(msynth->card, msynth->device,
230 msynth->subdevice,
231 SNDRV_RAWMIDI_LFLG_OUTPUT,
232 &msynth->output_rfile)) < 0) {
233 snd_printd("midi output open failed!!!\n");
234 return err;
235 }
236 memset(¶ms, 0, sizeof(params));
237 params.avail_min = 1;
238 params.buffer_size = output_buffer_size;
239 params.no_active_sensing = 1;
240 if ((err = snd_rawmidi_output_params(msynth->output_rfile.output, ¶ms)) < 0) {
241 snd_rawmidi_kernel_release(&msynth->output_rfile);
242 return err;
243 }
244 snd_midi_event_reset_decode(msynth->parser);
245 return 0;
246 }
247
248 /* close associated midi device for output */
249 static int midisynth_unuse(void *private_data, struct snd_seq_port_subscribe *info)
250 {
251 struct seq_midisynth *msynth = private_data;
252 unsigned char buf = 0xff; /* MIDI reset */
253
254 if (snd_BUG_ON(!msynth->output_rfile.output))
255 return -EINVAL;
256 /* sending single MIDI reset message to shut the device up */
257 snd_rawmidi_kernel_write(msynth->output_rfile.output, &buf, 1);
258 snd_rawmidi_drain_output(msynth->output_rfile.output);
259 return snd_rawmidi_kernel_release(&msynth->output_rfile);
260 }
261
262 /* delete given midi synth port */
263 static void snd_seq_midisynth_delete(struct seq_midisynth *msynth)
264 {
265 if (msynth == NULL)
266 return;
267
268 if (msynth->seq_client > 0) {
269 /* delete port */
270 snd_seq_event_port_detach(msynth->seq_client, msynth->seq_port);
271 }
272
273 if (msynth->parser)
274 snd_midi_event_free(msynth->parser);
275 }
276
277 /* register new midi synth port */
278 static int
279 snd_seq_midisynth_register_port(struct snd_seq_device *dev)
280 {
281 struct seq_midisynth_client *client;
282 struct seq_midisynth *msynth, *ms;
283 struct snd_seq_port_info *port;
284 struct snd_rawmidi_info *info;
285 struct snd_rawmidi *rmidi = dev->private_data;
286 int newclient = 0;
287 unsigned int p, ports;
288 struct snd_seq_port_callback pcallbacks;
289 struct snd_card *card = dev->card;
290 int device = dev->device;
291 unsigned int input_count = 0, output_count = 0;
292
293 if (snd_BUG_ON(!card || device < 0 || device >= SNDRV_RAWMIDI_DEVICES))
294 return -EINVAL;
295 info = kmalloc(sizeof(*info), GFP_KERNEL);
296 if (! info)
297 return -ENOMEM;
298 info->device = device;
299 info->stream = SNDRV_RAWMIDI_STREAM_OUTPUT;
300 info->subdevice = 0;
301 if (snd_rawmidi_info_select(card, info) >= 0)
302 output_count = info->subdevices_count;
303 info->stream = SNDRV_RAWMIDI_STREAM_INPUT;
304 if (snd_rawmidi_info_select(card, info) >= 0) {
305 input_count = info->subdevices_count;
306 }
307 ports = output_count;
308 if (ports < input_count)
309 ports = input_count;
310 if (ports == 0) {
311 kfree(info);
312 return -ENODEV;
313 }
314 if (ports > (256 / SNDRV_RAWMIDI_DEVICES))
315 ports = 256 / SNDRV_RAWMIDI_DEVICES;
316
317 mutex_lock(®ister_mutex);
318 client = synths[card->number];
319 if (client == NULL) {
320 newclient = 1;
321 client = kzalloc(sizeof(*client), GFP_KERNEL);
322 if (client == NULL) {
323 mutex_unlock(®ister_mutex);
324 kfree(info);
325 return -ENOMEM;
326 }
327 client->seq_client =
328 snd_seq_create_kernel_client(
329 card, 0, "%s", card->shortname[0] ?
330 (const char *)card->shortname : "External MIDI");
331 if (client->seq_client < 0) {
332 kfree(client);
333 mutex_unlock(®ister_mutex);
334 kfree(info);
335 return -ENOMEM;
336 }
337 }
338
339 msynth = kcalloc(ports, sizeof(struct seq_midisynth), GFP_KERNEL);
340 port = kmalloc(sizeof(*port), GFP_KERNEL);
341 if (msynth == NULL || port == NULL)
342 goto __nomem;
343
344 for (p = 0; p < ports; p++) {
345 ms = &msynth[p];
346
347 if (snd_seq_midisynth_new(ms, card, device, p) < 0)
348 goto __nomem;
349
350 /* declare port */
351 memset(port, 0, sizeof(*port));
352 port->addr.client = client->seq_client;
353 port->addr.port = device * (256 / SNDRV_RAWMIDI_DEVICES) + p;
354 port->flags = SNDRV_SEQ_PORT_FLG_GIVEN_PORT;
355 memset(info, 0, sizeof(*info));
356 info->device = device;
357 if (p < output_count)
358 info->stream = SNDRV_RAWMIDI_STREAM_OUTPUT;
359 else
360 info->stream = SNDRV_RAWMIDI_STREAM_INPUT;
361 info->subdevice = p;
362 if (snd_rawmidi_info_select(card, info) >= 0)
363 strcpy(port->name, info->subname);
364 if (! port->name[0]) {
365 if (info->name[0]) {
366 if (ports > 1)
367 snprintf(port->name, sizeof(port->name), "%s-%d", info->name, p);
368 else
369 snprintf(port->name, sizeof(port->name), "%s", info->name);
370 } else {
371 /* last resort */
372 if (ports > 1)
373 sprintf(port->name, "MIDI %d-%d-%d", card->number, device, p);
374 else
375 sprintf(port->name, "MIDI %d-%d", card->number, device);
376 }
377 }
378 if ((info->flags & SNDRV_RAWMIDI_INFO_OUTPUT) && p < output_count)
379 port->capability |= SNDRV_SEQ_PORT_CAP_WRITE | SNDRV_SEQ_PORT_CAP_SYNC_WRITE | SNDRV_SEQ_PORT_CAP_SUBS_WRITE;
380 if ((info->flags & SNDRV_RAWMIDI_INFO_INPUT) && p < input_count)
381 port->capability |= SNDRV_SEQ_PORT_CAP_READ | SNDRV_SEQ_PORT_CAP_SYNC_READ | SNDRV_SEQ_PORT_CAP_SUBS_READ;
382 if ((port->capability & (SNDRV_SEQ_PORT_CAP_WRITE|SNDRV_SEQ_PORT_CAP_READ)) == (SNDRV_SEQ_PORT_CAP_WRITE|SNDRV_SEQ_PORT_CAP_READ) &&
383 info->flags & SNDRV_RAWMIDI_INFO_DUPLEX)
384 port->capability |= SNDRV_SEQ_PORT_CAP_DUPLEX;
385 port->type = SNDRV_SEQ_PORT_TYPE_MIDI_GENERIC
386 | SNDRV_SEQ_PORT_TYPE_HARDWARE
387 | SNDRV_SEQ_PORT_TYPE_PORT;
388 port->midi_channels = 16;
389 memset(&pcallbacks, 0, sizeof(pcallbacks));
390 pcallbacks.owner = THIS_MODULE;
391 pcallbacks.private_data = ms;
392 pcallbacks.subscribe = midisynth_subscribe;
393 pcallbacks.unsubscribe = midisynth_unsubscribe;
394 pcallbacks.use = midisynth_use;
395 pcallbacks.unuse = midisynth_unuse;
396 pcallbacks.event_input = event_process_midi;
397 port->kernel = &pcallbacks;
398 if (rmidi->ops && rmidi->ops->get_port_info)
399 rmidi->ops->get_port_info(rmidi, p, port);
400 if (snd_seq_kernel_client_ctl(client->seq_client, SNDRV_SEQ_IOCTL_CREATE_PORT, port)<0)
401 goto __nomem;
402 ms->seq_client = client->seq_client;
403 ms->seq_port = port->addr.port;
404 }
405 client->ports_per_device[device] = ports;
406 client->ports[device] = msynth;
407 client->num_ports++;
408 if (newclient)
409 synths[card->number] = client;
410 mutex_unlock(®ister_mutex);
411 kfree(info);
412 kfree(port);
413 return 0; /* success */
414
415 __nomem:
416 if (msynth != NULL) {
417 for (p = 0; p < ports; p++)
418 snd_seq_midisynth_delete(&msynth[p]);
419 kfree(msynth);
420 }
421 if (newclient) {
422 snd_seq_delete_kernel_client(client->seq_client);
423 kfree(client);
424 }
425 kfree(info);
426 kfree(port);
427 mutex_unlock(®ister_mutex);
428 return -ENOMEM;
429 }
430
431 /* release midi synth port */
432 static int
433 snd_seq_midisynth_unregister_port(struct snd_seq_device *dev)
434 {
435 struct seq_midisynth_client *client;
436 struct seq_midisynth *msynth;
437 struct snd_card *card = dev->card;
438 int device = dev->device, p, ports;
439
440 mutex_lock(®ister_mutex);
441 client = synths[card->number];
442 if (client == NULL || client->ports[device] == NULL) {
443 mutex_unlock(®ister_mutex);
444 return -ENODEV;
445 }
446 ports = client->ports_per_device[device];
447 client->ports_per_device[device] = 0;
448 msynth = client->ports[device];
449 client->ports[device] = NULL;
450 for (p = 0; p < ports; p++)
451 snd_seq_midisynth_delete(&msynth[p]);
452 kfree(msynth);
453 client->num_ports--;
454 if (client->num_ports <= 0) {
455 snd_seq_delete_kernel_client(client->seq_client);
456 synths[card->number] = NULL;
457 kfree(client);
458 }
459 mutex_unlock(®ister_mutex);
460 return 0;
461 }
462
463
464 static int __init alsa_seq_midi_init(void)
465 {
466 static struct snd_seq_dev_ops ops = {
467 snd_seq_midisynth_register_port,
468 snd_seq_midisynth_unregister_port,
469 };
470 memset(&synths, 0, sizeof(synths));
471 snd_seq_autoload_lock();
472 snd_seq_device_register_driver(SNDRV_SEQ_DEV_ID_MIDISYNTH, &ops, 0);
473 snd_seq_autoload_unlock();
474 return 0;
475 }
476
477 static void __exit alsa_seq_midi_exit(void)
478 {
479 snd_seq_device_unregister_driver(SNDRV_SEQ_DEV_ID_MIDISYNTH);
480 }
481
482 module_init(alsa_seq_midi_init)
483 module_exit(alsa_seq_midi_exit)
484
|
This page was automatically generated by the
LXR engine.
|