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