1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * OSS compatible sequencer driver
4 *
5 * open/close and reset interface
6 *
7 * Copyright (C) 1998-1999 Takashi Iwai <tiwai@suse.de>
8 */
9
10 #include "seq_oss_device.h"
11 #include "seq_oss_synth.h"
12 #include "seq_oss_midi.h"
13 #include "seq_oss_writeq.h"
14 #include "seq_oss_readq.h"
15 #include "seq_oss_timer.h"
16 #include "seq_oss_event.h"
17 #include <linux/init.h>
18 #include <linux/export.h>
19 #include <linux/moduleparam.h>
20 #include <linux/slab.h>
21 #include <linux/workqueue.h>
22
23 /*
24 * common variables
25 */
26 static int maxqlen = SNDRV_SEQ_OSS_MAX_QLEN;
27 module_param(maxqlen, int, 0444);
28 MODULE_PARM_DESC(maxqlen, "maximum queue length");
29
30 static int system_client = -1; /* ALSA sequencer client number */
31 static int system_port = -1;
32
33 static int num_clients;
34 static struct seq_oss_devinfo *client_table[SNDRV_SEQ_OSS_MAX_CLIENTS];
35
36
37 /*
38 * prototypes
39 */
40 static int receive_announce(struct snd_seq_event *ev, int direct, void *private, int atomic, int hop);
41 static int translate_mode(struct file *file);
42 static int create_port(struct seq_oss_devinfo *dp);
43 static int delete_port(struct seq_oss_devinfo *dp);
44 static int alloc_seq_queue(struct seq_oss_devinfo *dp);
45 static int delete_seq_queue(int queue);
46 static void free_devinfo(void *private);
47
48 #define call_ctl(type,rec) snd_seq_kernel_client_ctl(system_client, type, rec)
49
50
51 /* call snd_seq_oss_midi_lookup_ports() asynchronously */
async_call_lookup_ports(struct work_struct * work)52 static void async_call_lookup_ports(struct work_struct *work)
53 {
54 snd_seq_oss_midi_lookup_ports(system_client);
55 }
56
57 static DECLARE_WORK(async_lookup_work, async_call_lookup_ports);
58
59 /*
60 * create sequencer client for OSS sequencer
61 */
62 int __init
snd_seq_oss_create_client(void)63 snd_seq_oss_create_client(void)
64 {
65 int rc;
66 struct snd_seq_port_info *port;
67 struct snd_seq_port_callback port_callback;
68
69 port = kmalloc(sizeof(*port), GFP_KERNEL);
70 if (!port) {
71 rc = -ENOMEM;
72 goto __error;
73 }
74
75 /* create ALSA client */
76 rc = snd_seq_create_kernel_client(NULL, SNDRV_SEQ_CLIENT_OSS,
77 "OSS sequencer");
78 if (rc < 0)
79 goto __error;
80
81 system_client = rc;
82
83 /* create annoucement receiver port */
84 memset(port, 0, sizeof(*port));
85 strcpy(port->name, "Receiver");
86 port->addr.client = system_client;
87 port->capability = SNDRV_SEQ_PORT_CAP_WRITE; /* receive only */
88 port->type = 0;
89
90 memset(&port_callback, 0, sizeof(port_callback));
91 /* don't set port_callback.owner here. otherwise the module counter
92 * is incremented and we can no longer release the module..
93 */
94 port_callback.event_input = receive_announce;
95 port->kernel = &port_callback;
96
97 call_ctl(SNDRV_SEQ_IOCTL_CREATE_PORT, port);
98 if ((system_port = port->addr.port) >= 0) {
99 struct snd_seq_port_subscribe subs;
100
101 memset(&subs, 0, sizeof(subs));
102 subs.sender.client = SNDRV_SEQ_CLIENT_SYSTEM;
103 subs.sender.port = SNDRV_SEQ_PORT_SYSTEM_ANNOUNCE;
104 subs.dest.client = system_client;
105 subs.dest.port = system_port;
106 call_ctl(SNDRV_SEQ_IOCTL_SUBSCRIBE_PORT, &subs);
107 }
108 rc = 0;
109
110 /* look up midi devices */
111 schedule_work(&async_lookup_work);
112
113 __error:
114 kfree(port);
115 return rc;
116 }
117
118
119 /*
120 * receive annoucement from system port, and check the midi device
121 */
122 static int
receive_announce(struct snd_seq_event * ev,int direct,void * private,int atomic,int hop)123 receive_announce(struct snd_seq_event *ev, int direct, void *private, int atomic, int hop)
124 {
125 struct snd_seq_port_info pinfo;
126
127 if (atomic)
128 return 0; /* it must not happen */
129
130 switch (ev->type) {
131 case SNDRV_SEQ_EVENT_PORT_START:
132 case SNDRV_SEQ_EVENT_PORT_CHANGE:
133 if (ev->data.addr.client == system_client)
134 break; /* ignore myself */
135 memset(&pinfo, 0, sizeof(pinfo));
136 pinfo.addr = ev->data.addr;
137 if (call_ctl(SNDRV_SEQ_IOCTL_GET_PORT_INFO, &pinfo) >= 0)
138 snd_seq_oss_midi_check_new_port(&pinfo);
139 break;
140
141 case SNDRV_SEQ_EVENT_PORT_EXIT:
142 if (ev->data.addr.client == system_client)
143 break; /* ignore myself */
144 snd_seq_oss_midi_check_exit_port(ev->data.addr.client,
145 ev->data.addr.port);
146 break;
147 }
148 return 0;
149 }
150
151
152 /*
153 * delete OSS sequencer client
154 */
155 int
snd_seq_oss_delete_client(void)156 snd_seq_oss_delete_client(void)
157 {
158 cancel_work_sync(&async_lookup_work);
159 if (system_client >= 0)
160 snd_seq_delete_kernel_client(system_client);
161
162 snd_seq_oss_midi_clear_all();
163
164 return 0;
165 }
166
167
168 /*
169 * open sequencer device
170 */
171 int
snd_seq_oss_open(struct file * file,int level)172 snd_seq_oss_open(struct file *file, int level)
173 {
174 int i, rc;
175 struct seq_oss_devinfo *dp;
176
177 dp = kzalloc(sizeof(*dp), GFP_KERNEL);
178 if (!dp)
179 return -ENOMEM;
180
181 dp->cseq = system_client;
182 dp->port = -1;
183 dp->queue = -1;
184
185 for (i = 0; i < SNDRV_SEQ_OSS_MAX_CLIENTS; i++) {
186 if (client_table[i] == NULL)
187 break;
188 }
189
190 dp->index = i;
191 if (i >= SNDRV_SEQ_OSS_MAX_CLIENTS) {
192 pr_debug("ALSA: seq_oss: too many applications\n");
193 rc = -ENOMEM;
194 goto _error;
195 }
196
197 /* look up synth and midi devices */
198 snd_seq_oss_synth_setup(dp);
199 snd_seq_oss_midi_setup(dp);
200
201 if (dp->synth_opened == 0 && dp->max_mididev == 0) {
202 /* pr_err("ALSA: seq_oss: no device found\n"); */
203 rc = -ENODEV;
204 goto _error;
205 }
206
207 /* create port */
208 rc = create_port(dp);
209 if (rc < 0) {
210 pr_err("ALSA: seq_oss: can't create port\n");
211 goto _error;
212 }
213
214 /* allocate queue */
215 rc = alloc_seq_queue(dp);
216 if (rc < 0)
217 goto _error;
218
219 /* set address */
220 dp->addr.client = dp->cseq;
221 dp->addr.port = dp->port;
222 /*dp->addr.queue = dp->queue;*/
223 /*dp->addr.channel = 0;*/
224
225 dp->seq_mode = level;
226
227 /* set up file mode */
228 dp->file_mode = translate_mode(file);
229
230 /* initialize read queue */
231 if (is_read_mode(dp->file_mode)) {
232 dp->readq = snd_seq_oss_readq_new(dp, maxqlen);
233 if (!dp->readq) {
234 rc = -ENOMEM;
235 goto _error;
236 }
237 }
238
239 /* initialize write queue */
240 if (is_write_mode(dp->file_mode)) {
241 dp->writeq = snd_seq_oss_writeq_new(dp, maxqlen);
242 if (!dp->writeq) {
243 rc = -ENOMEM;
244 goto _error;
245 }
246 }
247
248 /* initialize timer */
249 dp->timer = snd_seq_oss_timer_new(dp);
250 if (!dp->timer) {
251 pr_err("ALSA: seq_oss: can't alloc timer\n");
252 rc = -ENOMEM;
253 goto _error;
254 }
255
256 /* set private data pointer */
257 file->private_data = dp;
258
259 /* set up for mode2 */
260 if (level == SNDRV_SEQ_OSS_MODE_MUSIC)
261 snd_seq_oss_synth_setup_midi(dp);
262 else if (is_read_mode(dp->file_mode))
263 snd_seq_oss_midi_open_all(dp, SNDRV_SEQ_OSS_FILE_READ);
264
265 client_table[dp->index] = dp;
266 num_clients++;
267
268 return 0;
269
270 _error:
271 snd_seq_oss_synth_cleanup(dp);
272 snd_seq_oss_midi_cleanup(dp);
273 delete_seq_queue(dp->queue);
274 delete_port(dp);
275
276 return rc;
277 }
278
279 /*
280 * translate file flags to private mode
281 */
282 static int
translate_mode(struct file * file)283 translate_mode(struct file *file)
284 {
285 int file_mode = 0;
286 if ((file->f_flags & O_ACCMODE) != O_RDONLY)
287 file_mode |= SNDRV_SEQ_OSS_FILE_WRITE;
288 if ((file->f_flags & O_ACCMODE) != O_WRONLY)
289 file_mode |= SNDRV_SEQ_OSS_FILE_READ;
290 if (file->f_flags & O_NONBLOCK)
291 file_mode |= SNDRV_SEQ_OSS_FILE_NONBLOCK;
292 return file_mode;
293 }
294
295
296 /*
297 * create sequencer port
298 */
299 static int
create_port(struct seq_oss_devinfo * dp)300 create_port(struct seq_oss_devinfo *dp)
301 {
302 int rc;
303 struct snd_seq_port_info port;
304 struct snd_seq_port_callback callback;
305
306 memset(&port, 0, sizeof(port));
307 port.addr.client = dp->cseq;
308 sprintf(port.name, "Sequencer-%d", dp->index);
309 port.capability = SNDRV_SEQ_PORT_CAP_READ|SNDRV_SEQ_PORT_CAP_WRITE; /* no subscription */
310 port.type = SNDRV_SEQ_PORT_TYPE_SPECIFIC;
311 port.midi_channels = 128;
312 port.synth_voices = 128;
313
314 memset(&callback, 0, sizeof(callback));
315 callback.owner = THIS_MODULE;
316 callback.private_data = dp;
317 callback.event_input = snd_seq_oss_event_input;
318 callback.private_free = free_devinfo;
319 port.kernel = &callback;
320
321 rc = call_ctl(SNDRV_SEQ_IOCTL_CREATE_PORT, &port);
322 if (rc < 0)
323 return rc;
324
325 dp->port = port.addr.port;
326
327 return 0;
328 }
329
330 /*
331 * delete ALSA port
332 */
333 static int
delete_port(struct seq_oss_devinfo * dp)334 delete_port(struct seq_oss_devinfo *dp)
335 {
336 if (dp->port < 0) {
337 kfree(dp);
338 return 0;
339 }
340
341 return snd_seq_event_port_detach(dp->cseq, dp->port);
342 }
343
344 /*
345 * allocate a queue
346 */
347 static int
alloc_seq_queue(struct seq_oss_devinfo * dp)348 alloc_seq_queue(struct seq_oss_devinfo *dp)
349 {
350 struct snd_seq_queue_info qinfo;
351 int rc;
352
353 memset(&qinfo, 0, sizeof(qinfo));
354 qinfo.owner = system_client;
355 qinfo.locked = 1;
356 strcpy(qinfo.name, "OSS Sequencer Emulation");
357 if ((rc = call_ctl(SNDRV_SEQ_IOCTL_CREATE_QUEUE, &qinfo)) < 0)
358 return rc;
359 dp->queue = qinfo.queue;
360 return 0;
361 }
362
363 /*
364 * release queue
365 */
366 static int
delete_seq_queue(int queue)367 delete_seq_queue(int queue)
368 {
369 struct snd_seq_queue_info qinfo;
370 int rc;
371
372 if (queue < 0)
373 return 0;
374 memset(&qinfo, 0, sizeof(qinfo));
375 qinfo.queue = queue;
376 rc = call_ctl(SNDRV_SEQ_IOCTL_DELETE_QUEUE, &qinfo);
377 if (rc < 0)
378 pr_err("ALSA: seq_oss: unable to delete queue %d (%d)\n", queue, rc);
379 return rc;
380 }
381
382
383 /*
384 * free device informations - private_free callback of port
385 */
386 static void
free_devinfo(void * private)387 free_devinfo(void *private)
388 {
389 struct seq_oss_devinfo *dp = (struct seq_oss_devinfo *)private;
390
391 snd_seq_oss_timer_delete(dp->timer);
392
393 snd_seq_oss_writeq_delete(dp->writeq);
394
395 snd_seq_oss_readq_delete(dp->readq);
396
397 kfree(dp);
398 }
399
400
401 /*
402 * close sequencer device
403 */
404 void
snd_seq_oss_release(struct seq_oss_devinfo * dp)405 snd_seq_oss_release(struct seq_oss_devinfo *dp)
406 {
407 int queue;
408
409 client_table[dp->index] = NULL;
410 num_clients--;
411
412 snd_seq_oss_reset(dp);
413
414 snd_seq_oss_synth_cleanup(dp);
415 snd_seq_oss_midi_cleanup(dp);
416
417 /* clear slot */
418 queue = dp->queue;
419 if (dp->port >= 0)
420 delete_port(dp);
421 delete_seq_queue(queue);
422 }
423
424
425 /*
426 * reset sequencer devices
427 */
428 void
snd_seq_oss_reset(struct seq_oss_devinfo * dp)429 snd_seq_oss_reset(struct seq_oss_devinfo *dp)
430 {
431 int i;
432
433 /* reset all synth devices */
434 for (i = 0; i < dp->max_synthdev; i++)
435 snd_seq_oss_synth_reset(dp, i);
436
437 /* reset all midi devices */
438 if (dp->seq_mode != SNDRV_SEQ_OSS_MODE_MUSIC) {
439 for (i = 0; i < dp->max_mididev; i++)
440 snd_seq_oss_midi_reset(dp, i);
441 }
442
443 /* remove queues */
444 if (dp->readq)
445 snd_seq_oss_readq_clear(dp->readq);
446 if (dp->writeq)
447 snd_seq_oss_writeq_clear(dp->writeq);
448
449 /* reset timer */
450 snd_seq_oss_timer_stop(dp->timer);
451 }
452
453 #ifdef CONFIG_SND_PROC_FS
454 /*
455 * misc. functions for proc interface
456 */
457 char *
enabled_str(int bool)458 enabled_str(int bool)
459 {
460 return bool ? "enabled" : "disabled";
461 }
462
463 static char *
filemode_str(int val)464 filemode_str(int val)
465 {
466 static char *str[] = {
467 "none", "read", "write", "read/write",
468 };
469 return str[val & SNDRV_SEQ_OSS_FILE_ACMODE];
470 }
471
472
473 /*
474 * proc interface
475 */
476 void
snd_seq_oss_system_info_read(struct snd_info_buffer * buf)477 snd_seq_oss_system_info_read(struct snd_info_buffer *buf)
478 {
479 int i;
480 struct seq_oss_devinfo *dp;
481
482 snd_iprintf(buf, "ALSA client number %d\n", system_client);
483 snd_iprintf(buf, "ALSA receiver port %d\n", system_port);
484
485 snd_iprintf(buf, "\nNumber of applications: %d\n", num_clients);
486 for (i = 0; i < num_clients; i++) {
487 snd_iprintf(buf, "\nApplication %d: ", i);
488 if ((dp = client_table[i]) == NULL) {
489 snd_iprintf(buf, "*empty*\n");
490 continue;
491 }
492 snd_iprintf(buf, "port %d : queue %d\n", dp->port, dp->queue);
493 snd_iprintf(buf, " sequencer mode = %s : file open mode = %s\n",
494 (dp->seq_mode ? "music" : "synth"),
495 filemode_str(dp->file_mode));
496 if (dp->seq_mode)
497 snd_iprintf(buf, " timer tempo = %d, timebase = %d\n",
498 dp->timer->oss_tempo, dp->timer->oss_timebase);
499 snd_iprintf(buf, " max queue length %d\n", maxqlen);
500 if (is_read_mode(dp->file_mode) && dp->readq)
501 snd_seq_oss_readq_info_read(dp->readq, buf);
502 }
503 }
504 #endif /* CONFIG_SND_PROC_FS */
505
