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@suse.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 <sound/driver.h>
30 #include <linux/init.h>
31 #include <linux/slab.h>
32 #include <linux/errno.h>
33 #include <linux/string.h>
34 #include <linux/moduleparam.h>
35 #include <asm/semaphore.h>
36 #include <sound/core.h>
37 #include <sound/rawmidi.h>
38 #include <sound/seq_kernel.h>
39 #include <sound/seq_device.h>
40 #include <sound/seq_midi_event.h>
41 #include <sound/initval.h>
42
43 MODULE_AUTHOR("Frank van de Pol <fvdpol@coil.demon.nl>, Jaroslav Kysela <perex@suse.cz>");
44 MODULE_DESCRIPTION("Advanced Linux Sound Architecture sequencer MIDI synth.");
45 MODULE_LICENSE("GPL");
46 static int output_buffer_size = PAGE_SIZE;
47 module_param(output_buffer_size, int, 0644);
48 MODULE_PARM_DESC(output_buffer_size, "Output buffer size in bytes.");
49 static int input_buffer_size = PAGE_SIZE;
50 module_param(input_buffer_size, int, 0644);
51 MODULE_PARM_DESC(input_buffer_size, "Input buffer size in bytes.");
52
53 /* data for this midi synth driver */
54 typedef struct {
55 snd_card_t *card;
56 int device;
57 int subdevice;
58 snd_rawmidi_file_t input_rfile;
59 snd_rawmidi_file_t output_rfile;
60 int seq_client;
61 int seq_port;
62 snd_midi_event_t *parser;
63 } seq_midisynth_t;
64
65 typedef struct {
66 int seq_client;
67 int num_ports;
68 int ports_per_device[SNDRV_RAWMIDI_DEVICES];
69 seq_midisynth_t *ports[SNDRV_RAWMIDI_DEVICES];
70 } seq_midisynth_client_t;
71
72 static seq_midisynth_client_t *synths[SNDRV_CARDS];
73 static DECLARE_MUTEX(register_mutex);
74
75 /* handle rawmidi input event (MIDI v1.0 stream) */
76 static void snd_midi_input_event(snd_rawmidi_substream_t * substream)
77 {
78 snd_rawmidi_runtime_t *runtime;
79 seq_midisynth_t *msynth;
80 snd_seq_event_t ev;
81 char buf[16], *pbuf;
82 long res, count;
83
84 if (substream == NULL)
85 return;
86 runtime = substream->runtime;
87 msynth = (seq_midisynth_t *) runtime->private_data;
88 if (msynth == NULL)
89 return;
90 memset(&ev, 0, sizeof(ev));
91 while (runtime->avail > 0) {
92 res = snd_rawmidi_kernel_read(substream, buf, sizeof(buf));
93 if (res <= 0)
94 continue;
95 if (msynth->parser == NULL)
96 continue;
97 pbuf = buf;
98 while (res > 0) {
99 count = snd_midi_event_encode(msynth->parser, pbuf, res, &ev);
100 if (count < 0)
101 break;
102 pbuf += count;
103 res -= count;
104 if (ev.type != SNDRV_SEQ_EVENT_NONE) {
105 ev.source.port = msynth->seq_port;
106 ev.dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS;
107 snd_seq_kernel_client_dispatch(msynth->seq_client, &ev, 1, 0);
108 /* clear event and reset header */
109 memset(&ev, 0, sizeof(ev));
110 }
111 }
112 }
113 }
114
115 static int dump_midi(snd_rawmidi_substream_t *substream, const char *buf, int count)
116 {
117 snd_rawmidi_runtime_t *runtime;
118 int tmp;
119
120 snd_assert(substream != NULL || buf != NULL, 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(snd_seq_event_t * ev, int direct,
132 void *private_data, int atomic, int hop)
133 {
134 seq_midisynth_t *msynth = (seq_midisynth_t *) private_data;
135 unsigned char msg[10]; /* buffer for constructing midi messages */
136 snd_rawmidi_substream_t *substream;
137 int res;
138
139 snd_assert(msynth != NULL, return -EINVAL);
140 substream = msynth->output_rfile.output;
141 if (substream == NULL)
142 return -ENODEV;
143 if (ev->type == SNDRV_SEQ_EVENT_SYSEX) { /* special case, to save space */
144 if ((ev->flags & SNDRV_SEQ_EVENT_LENGTH_MASK) != SNDRV_SEQ_EVENT_LENGTH_VARIABLE) {
145 /* invalid event */
146 snd_printd("seq_midi: invalid sysex event flags = 0x%x\n", ev->flags);
147 return 0;
148 }
149 res = snd_seq_dump_var_event(ev, (snd_seq_dump_func_t)dump_midi, substream);
150 snd_midi_event_reset_decode(msynth->parser);
151 if (res < 0)
152 return res;
153 } else {
154 if (msynth->parser == NULL)
155 return -EIO;
156 res = snd_midi_event_decode(msynth->parser, msg, sizeof(msg), ev);
157 if (res < 0)
158 return res;
159 if ((res = dump_midi(substream, msg, res)) < 0) {
160 snd_midi_event_reset_decode(msynth->parser);
161 return res;
162 }
163 }
164 return 0;
165 }
166
167
168 static int snd_seq_midisynth_new(seq_midisynth_t *msynth,
169 snd_card_t *card,
170 int device,
171 int subdevice)
172 {
173 if (snd_midi_event_new(MAX_MIDI_EVENT_BUF, &msynth->parser) < 0)
174 return -ENOMEM;
175 msynth->card = card;
176 msynth->device = device;
177 msynth->subdevice = subdevice;
178 return 0;
179 }
180
181 /* open associated midi device for input */
182 static int midisynth_subscribe(void *private_data, snd_seq_port_subscribe_t *info)
183 {
184 int err;
185 seq_midisynth_t *msynth = (seq_midisynth_t *)private_data;
186 snd_rawmidi_runtime_t *runtime;
187 snd_rawmidi_params_t params;
188
189 /* open midi port */
190 if ((err = snd_rawmidi_kernel_open(msynth->card->number, msynth->device, msynth->subdevice, SNDRV_RAWMIDI_LFLG_INPUT, &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, snd_seq_port_subscribe_t *info)
211 {
212 int err;
213 seq_midisynth_t *msynth = (seq_midisynth_t *)private_data;
214
215 snd_assert(msynth->input_rfile.input != NULL, return -EINVAL);
216 err = snd_rawmidi_kernel_release(&msynth->input_rfile);
217 return err;
218 }
219
220 /* open associated midi device for output */
221 static int midisynth_use(void *private_data, snd_seq_port_subscribe_t *info)
222 {
223 int err;
224 seq_midisynth_t *msynth = (seq_midisynth_t *)private_data;
225 snd_rawmidi_params_t params;
226
227 /* open midi port */
228 if ((err = snd_rawmidi_kernel_open(msynth->card->number, msynth->device, msynth->subdevice, SNDRV_RAWMIDI_LFLG_OUTPUT, &msynth->output_rfile)) < 0) {
229 snd_printd("midi output open failed!!!\n");
230 return err;
231 }
232 memset(¶ms, 0, sizeof(params));
233 params.avail_min = 1;
234 params.buffer_size = output_buffer_size;
235 if ((err = snd_rawmidi_output_params(msynth->output_rfile.output, ¶ms)) < 0) {
236 snd_rawmidi_kernel_release(&msynth->output_rfile);
237 return err;
238 }
239 snd_midi_event_reset_decode(msynth->parser);
240 return 0;
241 }
242
243 /* close associated midi device for output */
244 static int midisynth_unuse(void *private_data, snd_seq_port_subscribe_t *info)
245 {
246 seq_midisynth_t *msynth = (seq_midisynth_t *)private_data;
247 unsigned char buf = 0xff; /* MIDI reset */
248
249 snd_assert(msynth->output_rfile.output != NULL, return -EINVAL);
250 /* sending single MIDI reset message to shut the device up */
251 snd_rawmidi_kernel_write(msynth->output_rfile.output, &buf, 1);
252 snd_rawmidi_drain_output(msynth->output_rfile.output);
253 return snd_rawmidi_kernel_release(&msynth->output_rfile);
254 }
255
256 /* delete given midi synth port */
257 static void snd_seq_midisynth_delete(seq_midisynth_t *msynth)
258 {
259 if (msynth == NULL)
260 return;
261
262 if (msynth->seq_client > 0) {
263 /* delete port */
264 snd_seq_event_port_detach(msynth->seq_client, msynth->seq_port);
265 }
266
267 if (msynth->parser)
268 snd_midi_event_free(msynth->parser);
269 }
270
271 /* set our client name */
272 static int set_client_name(seq_midisynth_client_t *client, snd_card_t *card,
273 snd_rawmidi_info_t *rmidi)
274 {
275 snd_seq_client_info_t cinfo;
276 const char *name;
277
278 memset(&cinfo, 0, sizeof(cinfo));
279 cinfo.client = client->seq_client;
280 cinfo.type = KERNEL_CLIENT;
281 name = rmidi->name[0] ? (const char *)rmidi->name : "External MIDI";
282 strlcpy(cinfo.name, name, sizeof(cinfo.name));
283 return snd_seq_kernel_client_ctl(client->seq_client, SNDRV_SEQ_IOCTL_SET_CLIENT_INFO, &cinfo);
284 }
285
286 /* register new midi synth port */
287 static int
288 snd_seq_midisynth_register_port(snd_seq_device_t *dev)
289 {
290 seq_midisynth_client_t *client;
291 seq_midisynth_t *msynth, *ms;
292 snd_seq_port_info_t port;
293 snd_rawmidi_info_t info;
294 int newclient = 0;
295 unsigned int p, ports;
296 snd_seq_client_callback_t callbacks;
297 snd_seq_port_callback_t pcallbacks;
298 snd_card_t *card = dev->card;
299 int device = dev->device;
300 unsigned int input_count = 0, output_count = 0;
301
302 snd_assert(card != NULL && device >= 0 && device < SNDRV_RAWMIDI_DEVICES, return -EINVAL);
303 info.device = device;
304 info.stream = SNDRV_RAWMIDI_STREAM_OUTPUT;
305 info.subdevice = 0;
306 if (snd_rawmidi_info_select(card, &info) >= 0)
307 output_count = info.subdevices_count;
308 info.stream = SNDRV_RAWMIDI_STREAM_INPUT;
309 if (snd_rawmidi_info_select(card, &info) >= 0) {
310 input_count = info.subdevices_count;
311 }
312 ports = output_count;
313 if (ports < input_count)
314 ports = input_count;
315 if (ports == 0)
316 return -ENODEV;
317 if (ports > (256 / SNDRV_RAWMIDI_DEVICES))
318 ports = 256 / SNDRV_RAWMIDI_DEVICES;
319
320 down(®ister_mutex);
321 client = synths[card->number];
322 if (client == NULL) {
323 newclient = 1;
324 client = kcalloc(1, sizeof(*client), GFP_KERNEL);
325 if (client == NULL) {
326 up(®ister_mutex);
327 return -ENOMEM;
328 }
329 memset(&callbacks, 0, sizeof(callbacks));
330 callbacks.private_data = client;
331 callbacks.allow_input = callbacks.allow_output = 1;
332 client->seq_client = snd_seq_create_kernel_client(card, 0, &callbacks);
333 if (client->seq_client < 0) {
334 kfree(client);
335 up(®ister_mutex);
336 return -ENOMEM;
337 }
338 set_client_name(client, card, &info);
339 } else if (device == 0)
340 set_client_name(client, card, &info); /* use the first device's name */
341
342 msynth = kcalloc(ports, sizeof(seq_midisynth_t), GFP_KERNEL);
343 if (msynth == NULL)
344 goto __nomem;
345
346 for (p = 0; p < ports; p++) {
347 ms = &msynth[p];
348
349 if (snd_seq_midisynth_new(ms, card, device, p) < 0)
350 goto __nomem;
351
352 /* declare port */
353 memset(&port, 0, sizeof(port));
354 port.addr.client = client->seq_client;
355 port.addr.port = device * (256 / SNDRV_RAWMIDI_DEVICES) + p;
356 port.flags = SNDRV_SEQ_PORT_FLG_GIVEN_PORT;
357 memset(&info, 0, sizeof(info));
358 info.device = device;
359 if (p < output_count)
360 info.stream = SNDRV_RAWMIDI_STREAM_OUTPUT;
361 else
362 info.stream = SNDRV_RAWMIDI_STREAM_INPUT;
363 info.subdevice = p;
364 if (snd_rawmidi_info_select(card, &info) >= 0)
365 strcpy(port.name, info.subname);
366 if (! port.name[0]) {
367 if (info.name[0]) {
368 if (ports > 1)
369 snprintf(port.name, sizeof(port.name), "%s-%d", info.name, p);
370 else
371 snprintf(port.name, sizeof(port.name), "%s", info.name);
372 } else {
373 /* last resort */
374 if (ports > 1)
375 sprintf(port.name, "MIDI %d-%d-%d", card->number, device, p);
376 else
377 sprintf(port.name, "MIDI %d-%d", card->number, device);
378 }
379 }
380 if ((info.flags & SNDRV_RAWMIDI_INFO_OUTPUT) && p < output_count)
381 port.capability |= SNDRV_SEQ_PORT_CAP_WRITE | SNDRV_SEQ_PORT_CAP_SYNC_WRITE | SNDRV_SEQ_PORT_CAP_SUBS_WRITE;
382 if ((info.flags & SNDRV_RAWMIDI_INFO_INPUT) && p < input_count)
383 port.capability |= SNDRV_SEQ_PORT_CAP_READ | SNDRV_SEQ_PORT_CAP_SYNC_READ | SNDRV_SEQ_PORT_CAP_SUBS_READ;
384 if ((port.capability & (SNDRV_SEQ_PORT_CAP_WRITE|SNDRV_SEQ_PORT_CAP_READ)) == (SNDRV_SEQ_PORT_CAP_WRITE|SNDRV_SEQ_PORT_CAP_READ) &&
385 info.flags & SNDRV_RAWMIDI_INFO_DUPLEX)
386 port.capability |= SNDRV_SEQ_PORT_CAP_DUPLEX;
387 port.type = SNDRV_SEQ_PORT_TYPE_MIDI_GENERIC;
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 (snd_seq_kernel_client_ctl(client->seq_client, SNDRV_SEQ_IOCTL_CREATE_PORT, &port)<0)
399 goto __nomem;
400 ms->seq_client = client->seq_client;
401 ms->seq_port = port.addr.port;
402 }
403 client->ports_per_device[device] = ports;
404 client->ports[device] = msynth;
405 client->num_ports++;
406 if (newclient)
407 synths[card->number] = client;
408 up(®ister_mutex);
409 return 0; /* success */
410
411 __nomem:
412 if (msynth != NULL) {
413 for (p = 0; p < ports; p++)
414 snd_seq_midisynth_delete(&msynth[p]);
415 kfree(msynth);
416 }
417 if (newclient) {
418 snd_seq_delete_kernel_client(client->seq_client);
419 kfree(client);
420 }
421 up(®ister_mutex);
422 return -ENOMEM;
423 }
424
425 /* release midi synth port */
426 static int
427 snd_seq_midisynth_unregister_port(snd_seq_device_t *dev)
428 {
429 seq_midisynth_client_t *client;
430 seq_midisynth_t *msynth;
431 snd_card_t *card = dev->card;
432 int device = dev->device, p, ports;
433
434 down(®ister_mutex);
435 client = synths[card->number];
436 if (client == NULL || client->ports[device] == NULL) {
437 up(®ister_mutex);
438 return -ENODEV;
439 }
440 ports = client->ports_per_device[device];
441 client->ports_per_device[device] = 0;
442 msynth = client->ports[device];
443 client->ports[device] = NULL;
444 snd_runtime_check(msynth != NULL || ports <= 0, goto __skip);
445 for (p = 0; p < ports; p++)
446 snd_seq_midisynth_delete(&msynth[p]);
447 kfree(msynth);
448 __skip:
449 client->num_ports--;
450 if (client->num_ports <= 0) {
451 snd_seq_delete_kernel_client(client->seq_client);
452 synths[card->number] = NULL;
453 kfree(client);
454 }
455 up(®ister_mutex);
456 return 0;
457 }
458
459
460 static int __init alsa_seq_midi_init(void)
461 {
462 static snd_seq_dev_ops_t ops = {
463 snd_seq_midisynth_register_port,
464 snd_seq_midisynth_unregister_port,
465 };
466 memset(&synths, 0, sizeof(synths));
467 snd_seq_autoload_lock();
468 snd_seq_device_register_driver(SNDRV_SEQ_DEV_ID_MIDISYNTH, &ops, 0);
469 snd_seq_autoload_unlock();
470 return 0;
471 }
472
473 static void __exit alsa_seq_midi_exit(void)
474 {
475 snd_seq_device_unregister_driver(SNDRV_SEQ_DEV_ID_MIDISYNTH);
476 }
477
478 module_init(alsa_seq_midi_init)
479 module_exit(alsa_seq_midi_exit)
480
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