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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * ALSA sequencer Timing queue handling
4 * Copyright (c) 1998-1999 by Frank van de Pol <fvdpol@coil.demon.nl>
5 *
6 * MAJOR CHANGES
7 * Nov. 13, 1999 Takashi Iwai <iwai@ww.uni-erlangen.de>
8 * - Queues are allocated dynamically via ioctl.
9 * - When owner client is deleted, all owned queues are deleted, too.
10 * - Owner of unlocked queue is kept unmodified even if it is
11 * manipulated by other clients.
12 * - Owner field in SET_QUEUE_OWNER ioctl must be identical with the
13 * caller client. i.e. Changing owner to a third client is not
14 * allowed.
15 *
16 * Aug. 30, 2000 Takashi Iwai
17 * - Queues are managed in static array again, but with better way.
18 * The API itself is identical.
19 * - The queue is locked when struct snd_seq_queue pointer is returned via
20 * queueptr(). This pointer *MUST* be released afterward by
21 * queuefree(ptr).
22 * - Addition of experimental sync support.
23 */
24
25#include <linux/init.h>
26#include <linux/slab.h>
27#include <sound/core.h>
28
29#include "seq_memory.h"
30#include "seq_queue.h"
31#include "seq_clientmgr.h"
32#include "seq_fifo.h"
33#include "seq_timer.h"
34#include "seq_info.h"
35
36/* list of allocated queues */
37static struct snd_seq_queue *queue_list[SNDRV_SEQ_MAX_QUEUES];
38static DEFINE_SPINLOCK(queue_list_lock);
39/* number of queues allocated */
40static int num_queues;
41
42int snd_seq_queue_get_cur_queues(void)
43{
44 return num_queues;
45}
46
47/*----------------------------------------------------------------*/
48
49/* assign queue id and insert to list */
50static int queue_list_add(struct snd_seq_queue *q)
51{
52 int i;
53 unsigned long flags;
54
55 spin_lock_irqsave(&queue_list_lock, flags);
56 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
57 if (! queue_list[i]) {
58 queue_list[i] = q;
59 q->queue = i;
60 num_queues++;
61 spin_unlock_irqrestore(&queue_list_lock, flags);
62 return i;
63 }
64 }
65 spin_unlock_irqrestore(&queue_list_lock, flags);
66 return -1;
67}
68
69static struct snd_seq_queue *queue_list_remove(int id, int client)
70{
71 struct snd_seq_queue *q;
72 unsigned long flags;
73
74 spin_lock_irqsave(&queue_list_lock, flags);
75 q = queue_list[id];
76 if (q) {
77 spin_lock(&q->owner_lock);
78 if (q->owner == client) {
79 /* found */
80 q->klocked = 1;
81 spin_unlock(&q->owner_lock);
82 queue_list[id] = NULL;
83 num_queues--;
84 spin_unlock_irqrestore(&queue_list_lock, flags);
85 return q;
86 }
87 spin_unlock(&q->owner_lock);
88 }
89 spin_unlock_irqrestore(&queue_list_lock, flags);
90 return NULL;
91}
92
93/*----------------------------------------------------------------*/
94
95/* create new queue (constructor) */
96static struct snd_seq_queue *queue_new(int owner, int locked)
97{
98 struct snd_seq_queue *q;
99
100 q = kzalloc(sizeof(*q), GFP_KERNEL);
101 if (!q)
102 return NULL;
103
104 spin_lock_init(&q->owner_lock);
105 spin_lock_init(&q->check_lock);
106 mutex_init(&q->timer_mutex);
107 snd_use_lock_init(&q->use_lock);
108 q->queue = -1;
109
110 q->tickq = snd_seq_prioq_new();
111 q->timeq = snd_seq_prioq_new();
112 q->timer = snd_seq_timer_new();
113 if (q->tickq == NULL || q->timeq == NULL || q->timer == NULL) {
114 snd_seq_prioq_delete(&q->tickq);
115 snd_seq_prioq_delete(&q->timeq);
116 snd_seq_timer_delete(&q->timer);
117 kfree(q);
118 return NULL;
119 }
120
121 q->owner = owner;
122 q->locked = locked;
123 q->klocked = 0;
124
125 return q;
126}
127
128/* delete queue (destructor) */
129static void queue_delete(struct snd_seq_queue *q)
130{
131 /* stop and release the timer */
132 mutex_lock(&q->timer_mutex);
133 snd_seq_timer_stop(q->timer);
134 snd_seq_timer_close(q);
135 mutex_unlock(&q->timer_mutex);
136 /* wait until access free */
137 snd_use_lock_sync(&q->use_lock);
138 /* release resources... */
139 snd_seq_prioq_delete(&q->tickq);
140 snd_seq_prioq_delete(&q->timeq);
141 snd_seq_timer_delete(&q->timer);
142
143 kfree(q);
144}
145
146
147/*----------------------------------------------------------------*/
148
149/* delete all existing queues */
150void snd_seq_queues_delete(void)
151{
152 int i;
153
154 /* clear list */
155 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
156 if (queue_list[i])
157 queue_delete(queue_list[i]);
158 }
159}
160
161static void queue_use(struct snd_seq_queue *queue, int client, int use);
162
163/* allocate a new queue -
164 * return pointer to new queue or ERR_PTR(-errno) for error
165 * The new queue's use_lock is set to 1. It is the caller's responsibility to
166 * call snd_use_lock_free(&q->use_lock).
167 */
168struct snd_seq_queue *snd_seq_queue_alloc(int client, int locked, unsigned int info_flags)
169{
170 struct snd_seq_queue *q;
171
172 q = queue_new(client, locked);
173 if (q == NULL)
174 return ERR_PTR(-ENOMEM);
175 q->info_flags = info_flags;
176 queue_use(q, client, 1);
177 snd_use_lock_use(&q->use_lock);
178 if (queue_list_add(q) < 0) {
179 snd_use_lock_free(&q->use_lock);
180 queue_delete(q);
181 return ERR_PTR(-ENOMEM);
182 }
183 return q;
184}
185
186/* delete a queue - queue must be owned by the client */
187int snd_seq_queue_delete(int client, int queueid)
188{
189 struct snd_seq_queue *q;
190
191 if (queueid < 0 || queueid >= SNDRV_SEQ_MAX_QUEUES)
192 return -EINVAL;
193 q = queue_list_remove(queueid, client);
194 if (q == NULL)
195 return -EINVAL;
196 queue_delete(q);
197
198 return 0;
199}
200
201
202/* return pointer to queue structure for specified id */
203struct snd_seq_queue *queueptr(int queueid)
204{
205 struct snd_seq_queue *q;
206 unsigned long flags;
207
208 if (queueid < 0 || queueid >= SNDRV_SEQ_MAX_QUEUES)
209 return NULL;
210 spin_lock_irqsave(&queue_list_lock, flags);
211 q = queue_list[queueid];
212 if (q)
213 snd_use_lock_use(&q->use_lock);
214 spin_unlock_irqrestore(&queue_list_lock, flags);
215 return q;
216}
217
218/* return the (first) queue matching with the specified name */
219struct snd_seq_queue *snd_seq_queue_find_name(char *name)
220{
221 int i;
222 struct snd_seq_queue *q;
223
224 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
225 q = queueptr(i);
226 if (q) {
227 if (strncmp(q->name, name, sizeof(q->name)) == 0)
228 return q;
229 queuefree(q);
230 }
231 }
232 return NULL;
233}
234
235
236/* -------------------------------------------------------- */
237
238#define MAX_CELL_PROCESSES_IN_QUEUE 1000
239
240void snd_seq_check_queue(struct snd_seq_queue *q, int atomic, int hop)
241{
242 unsigned long flags;
243 struct snd_seq_event_cell *cell;
244 snd_seq_tick_time_t cur_tick;
245 snd_seq_real_time_t cur_time;
246 int processed = 0;
247
248 if (q == NULL)
249 return;
250
251 /* make this function non-reentrant */
252 spin_lock_irqsave(&q->check_lock, flags);
253 if (q->check_blocked) {
254 q->check_again = 1;
255 spin_unlock_irqrestore(&q->check_lock, flags);
256 return; /* other thread is already checking queues */
257 }
258 q->check_blocked = 1;
259 spin_unlock_irqrestore(&q->check_lock, flags);
260
261 __again:
262 /* Process tick queue... */
263 cur_tick = snd_seq_timer_get_cur_tick(q->timer);
264 for (;;) {
265 cell = snd_seq_prioq_cell_out(q->tickq, &cur_tick);
266 if (!cell)
267 break;
268 snd_seq_dispatch_event(cell, atomic, hop);
269 if (++processed >= MAX_CELL_PROCESSES_IN_QUEUE)
270 goto out; /* the rest processed at the next batch */
271 }
272
273 /* Process time queue... */
274 cur_time = snd_seq_timer_get_cur_time(q->timer, false);
275 for (;;) {
276 cell = snd_seq_prioq_cell_out(q->timeq, &cur_time);
277 if (!cell)
278 break;
279 snd_seq_dispatch_event(cell, atomic, hop);
280 if (++processed >= MAX_CELL_PROCESSES_IN_QUEUE)
281 goto out; /* the rest processed at the next batch */
282 }
283
284 out:
285 /* free lock */
286 spin_lock_irqsave(&q->check_lock, flags);
287 if (q->check_again) {
288 q->check_again = 0;
289 if (processed < MAX_CELL_PROCESSES_IN_QUEUE) {
290 spin_unlock_irqrestore(&q->check_lock, flags);
291 goto __again;
292 }
293 }
294 q->check_blocked = 0;
295 spin_unlock_irqrestore(&q->check_lock, flags);
296}
297
298
299/* enqueue a event to singe queue */
300int snd_seq_enqueue_event(struct snd_seq_event_cell *cell, int atomic, int hop)
301{
302 int dest, err;
303 struct snd_seq_queue *q;
304
305 if (snd_BUG_ON(!cell))
306 return -EINVAL;
307 dest = cell->event.queue; /* destination queue */
308 q = queueptr(dest);
309 if (q == NULL)
310 return -EINVAL;
311 /* handle relative time stamps, convert them into absolute */
312 if ((cell->event.flags & SNDRV_SEQ_TIME_MODE_MASK) == SNDRV_SEQ_TIME_MODE_REL) {
313 switch (cell->event.flags & SNDRV_SEQ_TIME_STAMP_MASK) {
314 case SNDRV_SEQ_TIME_STAMP_TICK:
315 cell->event.time.tick += q->timer->tick.cur_tick;
316 break;
317
318 case SNDRV_SEQ_TIME_STAMP_REAL:
319 snd_seq_inc_real_time(&cell->event.time.time,
320 &q->timer->cur_time);
321 break;
322 }
323 cell->event.flags &= ~SNDRV_SEQ_TIME_MODE_MASK;
324 cell->event.flags |= SNDRV_SEQ_TIME_MODE_ABS;
325 }
326 /* enqueue event in the real-time or midi queue */
327 switch (cell->event.flags & SNDRV_SEQ_TIME_STAMP_MASK) {
328 case SNDRV_SEQ_TIME_STAMP_TICK:
329 err = snd_seq_prioq_cell_in(q->tickq, cell);
330 break;
331
332 case SNDRV_SEQ_TIME_STAMP_REAL:
333 default:
334 err = snd_seq_prioq_cell_in(q->timeq, cell);
335 break;
336 }
337
338 if (err < 0) {
339 queuefree(q); /* unlock */
340 return err;
341 }
342
343 /* trigger dispatching */
344 snd_seq_check_queue(q, atomic, hop);
345
346 queuefree(q); /* unlock */
347
348 return 0;
349}
350
351
352/*----------------------------------------------------------------*/
353
354static inline int check_access(struct snd_seq_queue *q, int client)
355{
356 return (q->owner == client) || (!q->locked && !q->klocked);
357}
358
359/* check if the client has permission to modify queue parameters.
360 * if it does, lock the queue
361 */
362static int queue_access_lock(struct snd_seq_queue *q, int client)
363{
364 unsigned long flags;
365 int access_ok;
366
367 spin_lock_irqsave(&q->owner_lock, flags);
368 access_ok = check_access(q, client);
369 if (access_ok)
370 q->klocked = 1;
371 spin_unlock_irqrestore(&q->owner_lock, flags);
372 return access_ok;
373}
374
375/* unlock the queue */
376static inline void queue_access_unlock(struct snd_seq_queue *q)
377{
378 unsigned long flags;
379
380 spin_lock_irqsave(&q->owner_lock, flags);
381 q->klocked = 0;
382 spin_unlock_irqrestore(&q->owner_lock, flags);
383}
384
385/* exported - only checking permission */
386int snd_seq_queue_check_access(int queueid, int client)
387{
388 struct snd_seq_queue *q = queueptr(queueid);
389 int access_ok;
390 unsigned long flags;
391
392 if (! q)
393 return 0;
394 spin_lock_irqsave(&q->owner_lock, flags);
395 access_ok = check_access(q, client);
396 spin_unlock_irqrestore(&q->owner_lock, flags);
397 queuefree(q);
398 return access_ok;
399}
400
401/*----------------------------------------------------------------*/
402
403/*
404 * change queue's owner and permission
405 */
406int snd_seq_queue_set_owner(int queueid, int client, int locked)
407{
408 struct snd_seq_queue *q = queueptr(queueid);
409 unsigned long flags;
410
411 if (q == NULL)
412 return -EINVAL;
413
414 if (! queue_access_lock(q, client)) {
415 queuefree(q);
416 return -EPERM;
417 }
418
419 spin_lock_irqsave(&q->owner_lock, flags);
420 q->locked = locked ? 1 : 0;
421 q->owner = client;
422 spin_unlock_irqrestore(&q->owner_lock, flags);
423 queue_access_unlock(q);
424 queuefree(q);
425
426 return 0;
427}
428
429
430/*----------------------------------------------------------------*/
431
432/* open timer -
433 * q->use mutex should be down before calling this function to avoid
434 * confliction with snd_seq_queue_use()
435 */
436int snd_seq_queue_timer_open(int queueid)
437{
438 int result = 0;
439 struct snd_seq_queue *queue;
440 struct snd_seq_timer *tmr;
441
442 queue = queueptr(queueid);
443 if (queue == NULL)
444 return -EINVAL;
445 tmr = queue->timer;
446 result = snd_seq_timer_open(queue);
447 if (result < 0) {
448 snd_seq_timer_defaults(tmr);
449 result = snd_seq_timer_open(queue);
450 }
451 queuefree(queue);
452 return result;
453}
454
455/* close timer -
456 * q->use mutex should be down before calling this function
457 */
458int snd_seq_queue_timer_close(int queueid)
459{
460 struct snd_seq_queue *queue;
461 int result = 0;
462
463 queue = queueptr(queueid);
464 if (queue == NULL)
465 return -EINVAL;
466 snd_seq_timer_close(queue);
467 queuefree(queue);
468 return result;
469}
470
471/* change queue tempo and ppq */
472int snd_seq_queue_timer_set_tempo(int queueid, int client,
473 struct snd_seq_queue_tempo *info)
474{
475 struct snd_seq_queue *q = queueptr(queueid);
476 int result;
477
478 if (q == NULL)
479 return -EINVAL;
480 if (! queue_access_lock(q, client)) {
481 queuefree(q);
482 return -EPERM;
483 }
484
485 result = snd_seq_timer_set_tempo_ppq(q->timer, info->tempo, info->ppq);
486 if (result >= 0 && info->skew_base > 0)
487 result = snd_seq_timer_set_skew(q->timer, info->skew_value,
488 info->skew_base);
489 queue_access_unlock(q);
490 queuefree(q);
491 return result;
492}
493
494/* use or unuse this queue */
495static void queue_use(struct snd_seq_queue *queue, int client, int use)
496{
497 if (use) {
498 if (!test_and_set_bit(client, queue->clients_bitmap))
499 queue->clients++;
500 } else {
501 if (test_and_clear_bit(client, queue->clients_bitmap))
502 queue->clients--;
503 }
504 if (queue->clients) {
505 if (use && queue->clients == 1)
506 snd_seq_timer_defaults(queue->timer);
507 snd_seq_timer_open(queue);
508 } else {
509 snd_seq_timer_close(queue);
510 }
511}
512
513/* use or unuse this queue -
514 * if it is the first client, starts the timer.
515 * if it is not longer used by any clients, stop the timer.
516 */
517int snd_seq_queue_use(int queueid, int client, int use)
518{
519 struct snd_seq_queue *queue;
520
521 queue = queueptr(queueid);
522 if (queue == NULL)
523 return -EINVAL;
524 mutex_lock(&queue->timer_mutex);
525 queue_use(queue, client, use);
526 mutex_unlock(&queue->timer_mutex);
527 queuefree(queue);
528 return 0;
529}
530
531/*
532 * check if queue is used by the client
533 * return negative value if the queue is invalid.
534 * return 0 if not used, 1 if used.
535 */
536int snd_seq_queue_is_used(int queueid, int client)
537{
538 struct snd_seq_queue *q;
539 int result;
540
541 q = queueptr(queueid);
542 if (q == NULL)
543 return -EINVAL; /* invalid queue */
544 result = test_bit(client, q->clients_bitmap) ? 1 : 0;
545 queuefree(q);
546 return result;
547}
548
549
550/*----------------------------------------------------------------*/
551
552/* final stage notification -
553 * remove cells for no longer exist client (for non-owned queue)
554 * or delete this queue (for owned queue)
555 */
556void snd_seq_queue_client_leave(int client)
557{
558 int i;
559 struct snd_seq_queue *q;
560
561 /* delete own queues from queue list */
562 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
563 q = queue_list_remove(i, client);
564 if (q)
565 queue_delete(q);
566 }
567
568 /* remove cells from existing queues -
569 * they are not owned by this client
570 */
571 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
572 q = queueptr(i);
573 if (!q)
574 continue;
575 if (test_bit(client, q->clients_bitmap)) {
576 snd_seq_prioq_leave(q->tickq, client, 0);
577 snd_seq_prioq_leave(q->timeq, client, 0);
578 snd_seq_queue_use(q->queue, client, 0);
579 }
580 queuefree(q);
581 }
582}
583
584
585
586/*----------------------------------------------------------------*/
587
588/* remove cells from all queues */
589void snd_seq_queue_client_leave_cells(int client)
590{
591 int i;
592 struct snd_seq_queue *q;
593
594 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
595 q = queueptr(i);
596 if (!q)
597 continue;
598 snd_seq_prioq_leave(q->tickq, client, 0);
599 snd_seq_prioq_leave(q->timeq, client, 0);
600 queuefree(q);
601 }
602}
603
604/* remove cells based on flush criteria */
605void snd_seq_queue_remove_cells(int client, struct snd_seq_remove_events *info)
606{
607 int i;
608 struct snd_seq_queue *q;
609
610 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
611 q = queueptr(i);
612 if (!q)
613 continue;
614 if (test_bit(client, q->clients_bitmap) &&
615 (! (info->remove_mode & SNDRV_SEQ_REMOVE_DEST) ||
616 q->queue == info->queue)) {
617 snd_seq_prioq_remove_events(q->tickq, client, info);
618 snd_seq_prioq_remove_events(q->timeq, client, info);
619 }
620 queuefree(q);
621 }
622}
623
624/*----------------------------------------------------------------*/
625
626/*
627 * send events to all subscribed ports
628 */
629static void queue_broadcast_event(struct snd_seq_queue *q, struct snd_seq_event *ev,
630 int atomic, int hop)
631{
632 struct snd_seq_event sev;
633
634 sev = *ev;
635
636 sev.flags = SNDRV_SEQ_TIME_STAMP_TICK|SNDRV_SEQ_TIME_MODE_ABS;
637 sev.time.tick = q->timer->tick.cur_tick;
638 sev.queue = q->queue;
639 sev.data.queue.queue = q->queue;
640
641 /* broadcast events from Timer port */
642 sev.source.client = SNDRV_SEQ_CLIENT_SYSTEM;
643 sev.source.port = SNDRV_SEQ_PORT_SYSTEM_TIMER;
644 sev.dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS;
645 snd_seq_kernel_client_dispatch(SNDRV_SEQ_CLIENT_SYSTEM, &sev, atomic, hop);
646}
647
648/*
649 * process a received queue-control event.
650 * this function is exported for seq_sync.c.
651 */
652static void snd_seq_queue_process_event(struct snd_seq_queue *q,
653 struct snd_seq_event *ev,
654 int atomic, int hop)
655{
656 switch (ev->type) {
657 case SNDRV_SEQ_EVENT_START:
658 snd_seq_prioq_leave(q->tickq, ev->source.client, 1);
659 snd_seq_prioq_leave(q->timeq, ev->source.client, 1);
660 if (! snd_seq_timer_start(q->timer))
661 queue_broadcast_event(q, ev, atomic, hop);
662 break;
663
664 case SNDRV_SEQ_EVENT_CONTINUE:
665 if (! snd_seq_timer_continue(q->timer))
666 queue_broadcast_event(q, ev, atomic, hop);
667 break;
668
669 case SNDRV_SEQ_EVENT_STOP:
670 snd_seq_timer_stop(q->timer);
671 queue_broadcast_event(q, ev, atomic, hop);
672 break;
673
674 case SNDRV_SEQ_EVENT_TEMPO:
675 snd_seq_timer_set_tempo(q->timer, ev->data.queue.param.value);
676 queue_broadcast_event(q, ev, atomic, hop);
677 break;
678
679 case SNDRV_SEQ_EVENT_SETPOS_TICK:
680 if (snd_seq_timer_set_position_tick(q->timer, ev->data.queue.param.time.tick) == 0) {
681 queue_broadcast_event(q, ev, atomic, hop);
682 }
683 break;
684
685 case SNDRV_SEQ_EVENT_SETPOS_TIME:
686 if (snd_seq_timer_set_position_time(q->timer, ev->data.queue.param.time.time) == 0) {
687 queue_broadcast_event(q, ev, atomic, hop);
688 }
689 break;
690 case SNDRV_SEQ_EVENT_QUEUE_SKEW:
691 if (snd_seq_timer_set_skew(q->timer,
692 ev->data.queue.param.skew.value,
693 ev->data.queue.param.skew.base) == 0) {
694 queue_broadcast_event(q, ev, atomic, hop);
695 }
696 break;
697 }
698}
699
700
701/*
702 * Queue control via timer control port:
703 * this function is exported as a callback of timer port.
704 */
705int snd_seq_control_queue(struct snd_seq_event *ev, int atomic, int hop)
706{
707 struct snd_seq_queue *q;
708
709 if (snd_BUG_ON(!ev))
710 return -EINVAL;
711 q = queueptr(ev->data.queue.queue);
712
713 if (q == NULL)
714 return -EINVAL;
715
716 if (! queue_access_lock(q, ev->source.client)) {
717 queuefree(q);
718 return -EPERM;
719 }
720
721 snd_seq_queue_process_event(q, ev, atomic, hop);
722
723 queue_access_unlock(q);
724 queuefree(q);
725 return 0;
726}
727
728
729/*----------------------------------------------------------------*/
730
731#ifdef CONFIG_SND_PROC_FS
732/* exported to seq_info.c */
733void snd_seq_info_queues_read(struct snd_info_entry *entry,
734 struct snd_info_buffer *buffer)
735{
736 int i, bpm;
737 struct snd_seq_queue *q;
738 struct snd_seq_timer *tmr;
739 bool locked;
740 int owner;
741
742 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
743 q = queueptr(i);
744 if (!q)
745 continue;
746
747 tmr = q->timer;
748 if (tmr->tempo)
749 bpm = 60000000 / tmr->tempo;
750 else
751 bpm = 0;
752
753 spin_lock_irq(&q->owner_lock);
754 locked = q->locked;
755 owner = q->owner;
756 spin_unlock_irq(&q->owner_lock);
757
758 snd_iprintf(buffer, "queue %d: [%s]\n", q->queue, q->name);
759 snd_iprintf(buffer, "owned by client : %d\n", owner);
760 snd_iprintf(buffer, "lock status : %s\n", locked ? "Locked" : "Free");
761 snd_iprintf(buffer, "queued time events : %d\n", snd_seq_prioq_avail(q->timeq));
762 snd_iprintf(buffer, "queued tick events : %d\n", snd_seq_prioq_avail(q->tickq));
763 snd_iprintf(buffer, "timer state : %s\n", tmr->running ? "Running" : "Stopped");
764 snd_iprintf(buffer, "timer PPQ : %d\n", tmr->ppq);
765 snd_iprintf(buffer, "current tempo : %d\n", tmr->tempo);
766 snd_iprintf(buffer, "current BPM : %d\n", bpm);
767 snd_iprintf(buffer, "current time : %d.%09d s\n", tmr->cur_time.tv_sec, tmr->cur_time.tv_nsec);
768 snd_iprintf(buffer, "current tick : %d\n", tmr->tick.cur_tick);
769 snd_iprintf(buffer, "\n");
770 queuefree(q);
771 }
772}
773#endif /* CONFIG_SND_PROC_FS */
774
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * ALSA sequencer Timing queue handling
4 * Copyright (c) 1998-1999 by Frank van de Pol <fvdpol@coil.demon.nl>
5 *
6 * MAJOR CHANGES
7 * Nov. 13, 1999 Takashi Iwai <iwai@ww.uni-erlangen.de>
8 * - Queues are allocated dynamically via ioctl.
9 * - When owner client is deleted, all owned queues are deleted, too.
10 * - Owner of unlocked queue is kept unmodified even if it is
11 * manipulated by other clients.
12 * - Owner field in SET_QUEUE_OWNER ioctl must be identical with the
13 * caller client. i.e. Changing owner to a third client is not
14 * allowed.
15 *
16 * Aug. 30, 2000 Takashi Iwai
17 * - Queues are managed in static array again, but with better way.
18 * The API itself is identical.
19 * - The queue is locked when struct snd_seq_queue pointer is returned via
20 * queueptr(). This pointer *MUST* be released afterward by
21 * queuefree(ptr).
22 * - Addition of experimental sync support.
23 */
24
25#include <linux/init.h>
26#include <linux/slab.h>
27#include <sound/core.h>
28
29#include "seq_memory.h"
30#include "seq_queue.h"
31#include "seq_clientmgr.h"
32#include "seq_fifo.h"
33#include "seq_timer.h"
34#include "seq_info.h"
35
36/* list of allocated queues */
37static struct snd_seq_queue *queue_list[SNDRV_SEQ_MAX_QUEUES];
38static DEFINE_SPINLOCK(queue_list_lock);
39/* number of queues allocated */
40static int num_queues;
41
42int snd_seq_queue_get_cur_queues(void)
43{
44 return num_queues;
45}
46
47/*----------------------------------------------------------------*/
48
49/* assign queue id and insert to list */
50static int queue_list_add(struct snd_seq_queue *q)
51{
52 int i;
53
54 guard(spinlock_irqsave)(&queue_list_lock);
55 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
56 if (! queue_list[i]) {
57 queue_list[i] = q;
58 q->queue = i;
59 num_queues++;
60 return i;
61 }
62 }
63 return -1;
64}
65
66static struct snd_seq_queue *queue_list_remove(int id, int client)
67{
68 struct snd_seq_queue *q;
69
70 guard(spinlock_irqsave)(&queue_list_lock);
71 q = queue_list[id];
72 if (q) {
73 guard(spinlock)(&q->owner_lock);
74 if (q->owner == client) {
75 /* found */
76 q->klocked = 1;
77 queue_list[id] = NULL;
78 num_queues--;
79 return q;
80 }
81 }
82 return NULL;
83}
84
85/*----------------------------------------------------------------*/
86
87/* create new queue (constructor) */
88static struct snd_seq_queue *queue_new(int owner, int locked)
89{
90 struct snd_seq_queue *q;
91
92 q = kzalloc(sizeof(*q), GFP_KERNEL);
93 if (!q)
94 return NULL;
95
96 spin_lock_init(&q->owner_lock);
97 spin_lock_init(&q->check_lock);
98 mutex_init(&q->timer_mutex);
99 snd_use_lock_init(&q->use_lock);
100 q->queue = -1;
101
102 q->tickq = snd_seq_prioq_new();
103 q->timeq = snd_seq_prioq_new();
104 q->timer = snd_seq_timer_new();
105 if (q->tickq == NULL || q->timeq == NULL || q->timer == NULL) {
106 snd_seq_prioq_delete(&q->tickq);
107 snd_seq_prioq_delete(&q->timeq);
108 snd_seq_timer_delete(&q->timer);
109 kfree(q);
110 return NULL;
111 }
112
113 q->owner = owner;
114 q->locked = locked;
115 q->klocked = 0;
116
117 return q;
118}
119
120/* delete queue (destructor) */
121static void queue_delete(struct snd_seq_queue *q)
122{
123 /* stop and release the timer */
124 mutex_lock(&q->timer_mutex);
125 snd_seq_timer_stop(q->timer);
126 snd_seq_timer_close(q);
127 mutex_unlock(&q->timer_mutex);
128 /* wait until access free */
129 snd_use_lock_sync(&q->use_lock);
130 /* release resources... */
131 snd_seq_prioq_delete(&q->tickq);
132 snd_seq_prioq_delete(&q->timeq);
133 snd_seq_timer_delete(&q->timer);
134
135 kfree(q);
136}
137
138
139/*----------------------------------------------------------------*/
140
141/* delete all existing queues */
142void snd_seq_queues_delete(void)
143{
144 int i;
145
146 /* clear list */
147 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
148 if (queue_list[i])
149 queue_delete(queue_list[i]);
150 }
151}
152
153static void queue_use(struct snd_seq_queue *queue, int client, int use);
154
155/* allocate a new queue -
156 * return pointer to new queue or ERR_PTR(-errno) for error
157 * The new queue's use_lock is set to 1. It is the caller's responsibility to
158 * call snd_use_lock_free(&q->use_lock).
159 */
160struct snd_seq_queue *snd_seq_queue_alloc(int client, int locked, unsigned int info_flags)
161{
162 struct snd_seq_queue *q;
163
164 q = queue_new(client, locked);
165 if (q == NULL)
166 return ERR_PTR(-ENOMEM);
167 q->info_flags = info_flags;
168 queue_use(q, client, 1);
169 snd_use_lock_use(&q->use_lock);
170 if (queue_list_add(q) < 0) {
171 snd_use_lock_free(&q->use_lock);
172 queue_delete(q);
173 return ERR_PTR(-ENOMEM);
174 }
175 return q;
176}
177
178/* delete a queue - queue must be owned by the client */
179int snd_seq_queue_delete(int client, int queueid)
180{
181 struct snd_seq_queue *q;
182
183 if (queueid < 0 || queueid >= SNDRV_SEQ_MAX_QUEUES)
184 return -EINVAL;
185 q = queue_list_remove(queueid, client);
186 if (q == NULL)
187 return -EINVAL;
188 queue_delete(q);
189
190 return 0;
191}
192
193
194/* return pointer to queue structure for specified id */
195struct snd_seq_queue *queueptr(int queueid)
196{
197 struct snd_seq_queue *q;
198
199 if (queueid < 0 || queueid >= SNDRV_SEQ_MAX_QUEUES)
200 return NULL;
201 guard(spinlock_irqsave)(&queue_list_lock);
202 q = queue_list[queueid];
203 if (q)
204 snd_use_lock_use(&q->use_lock);
205 return q;
206}
207
208/* return the (first) queue matching with the specified name */
209struct snd_seq_queue *snd_seq_queue_find_name(char *name)
210{
211 int i;
212 struct snd_seq_queue *q;
213
214 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
215 q = queueptr(i);
216 if (q) {
217 if (strncmp(q->name, name, sizeof(q->name)) == 0)
218 return q;
219 queuefree(q);
220 }
221 }
222 return NULL;
223}
224
225
226/* -------------------------------------------------------- */
227
228#define MAX_CELL_PROCESSES_IN_QUEUE 1000
229
230void snd_seq_check_queue(struct snd_seq_queue *q, int atomic, int hop)
231{
232 struct snd_seq_event_cell *cell;
233 snd_seq_tick_time_t cur_tick;
234 snd_seq_real_time_t cur_time;
235 int processed = 0;
236
237 if (q == NULL)
238 return;
239
240 /* make this function non-reentrant */
241 scoped_guard(spinlock_irqsave, &q->check_lock) {
242 if (q->check_blocked) {
243 q->check_again = 1;
244 return; /* other thread is already checking queues */
245 }
246 q->check_blocked = 1;
247 }
248
249 __again:
250 /* Process tick queue... */
251 cur_tick = snd_seq_timer_get_cur_tick(q->timer);
252 for (;;) {
253 cell = snd_seq_prioq_cell_out(q->tickq, &cur_tick);
254 if (!cell)
255 break;
256 snd_seq_dispatch_event(cell, atomic, hop);
257 if (++processed >= MAX_CELL_PROCESSES_IN_QUEUE)
258 goto out; /* the rest processed at the next batch */
259 }
260
261 /* Process time queue... */
262 cur_time = snd_seq_timer_get_cur_time(q->timer, false);
263 for (;;) {
264 cell = snd_seq_prioq_cell_out(q->timeq, &cur_time);
265 if (!cell)
266 break;
267 snd_seq_dispatch_event(cell, atomic, hop);
268 if (++processed >= MAX_CELL_PROCESSES_IN_QUEUE)
269 goto out; /* the rest processed at the next batch */
270 }
271
272 out:
273 /* free lock */
274 scoped_guard(spinlock_irqsave, &q->check_lock) {
275 if (q->check_again) {
276 q->check_again = 0;
277 if (processed < MAX_CELL_PROCESSES_IN_QUEUE)
278 goto __again;
279 }
280 q->check_blocked = 0;
281 }
282}
283
284
285/* enqueue a event to singe queue */
286int snd_seq_enqueue_event(struct snd_seq_event_cell *cell, int atomic, int hop)
287{
288 int dest, err;
289 struct snd_seq_queue *q;
290
291 if (snd_BUG_ON(!cell))
292 return -EINVAL;
293 dest = cell->event.queue; /* destination queue */
294 q = queueptr(dest);
295 if (q == NULL)
296 return -EINVAL;
297 /* handle relative time stamps, convert them into absolute */
298 if ((cell->event.flags & SNDRV_SEQ_TIME_MODE_MASK) == SNDRV_SEQ_TIME_MODE_REL) {
299 switch (cell->event.flags & SNDRV_SEQ_TIME_STAMP_MASK) {
300 case SNDRV_SEQ_TIME_STAMP_TICK:
301 cell->event.time.tick += q->timer->tick.cur_tick;
302 break;
303
304 case SNDRV_SEQ_TIME_STAMP_REAL:
305 snd_seq_inc_real_time(&cell->event.time.time,
306 &q->timer->cur_time);
307 break;
308 }
309 cell->event.flags &= ~SNDRV_SEQ_TIME_MODE_MASK;
310 cell->event.flags |= SNDRV_SEQ_TIME_MODE_ABS;
311 }
312 /* enqueue event in the real-time or midi queue */
313 switch (cell->event.flags & SNDRV_SEQ_TIME_STAMP_MASK) {
314 case SNDRV_SEQ_TIME_STAMP_TICK:
315 err = snd_seq_prioq_cell_in(q->tickq, cell);
316 break;
317
318 case SNDRV_SEQ_TIME_STAMP_REAL:
319 default:
320 err = snd_seq_prioq_cell_in(q->timeq, cell);
321 break;
322 }
323
324 if (err < 0) {
325 queuefree(q); /* unlock */
326 return err;
327 }
328
329 /* trigger dispatching */
330 snd_seq_check_queue(q, atomic, hop);
331
332 queuefree(q); /* unlock */
333
334 return 0;
335}
336
337
338/*----------------------------------------------------------------*/
339
340static inline int check_access(struct snd_seq_queue *q, int client)
341{
342 return (q->owner == client) || (!q->locked && !q->klocked);
343}
344
345/* check if the client has permission to modify queue parameters.
346 * if it does, lock the queue
347 */
348static int queue_access_lock(struct snd_seq_queue *q, int client)
349{
350 int access_ok;
351
352 guard(spinlock_irqsave)(&q->owner_lock);
353 access_ok = check_access(q, client);
354 if (access_ok)
355 q->klocked = 1;
356 return access_ok;
357}
358
359/* unlock the queue */
360static inline void queue_access_unlock(struct snd_seq_queue *q)
361{
362 guard(spinlock_irqsave)(&q->owner_lock);
363 q->klocked = 0;
364}
365
366/* exported - only checking permission */
367int snd_seq_queue_check_access(int queueid, int client)
368{
369 struct snd_seq_queue *q = queueptr(queueid);
370 int access_ok;
371
372 if (! q)
373 return 0;
374 scoped_guard(spinlock_irqsave, &q->owner_lock)
375 access_ok = check_access(q, client);
376 queuefree(q);
377 return access_ok;
378}
379
380/*----------------------------------------------------------------*/
381
382/*
383 * change queue's owner and permission
384 */
385int snd_seq_queue_set_owner(int queueid, int client, int locked)
386{
387 struct snd_seq_queue *q = queueptr(queueid);
388
389 if (q == NULL)
390 return -EINVAL;
391
392 if (! queue_access_lock(q, client)) {
393 queuefree(q);
394 return -EPERM;
395 }
396
397 scoped_guard(spinlock_irqsave, &q->owner_lock) {
398 q->locked = locked ? 1 : 0;
399 q->owner = client;
400 }
401 queue_access_unlock(q);
402 queuefree(q);
403
404 return 0;
405}
406
407
408/*----------------------------------------------------------------*/
409
410/* open timer -
411 * q->use mutex should be down before calling this function to avoid
412 * confliction with snd_seq_queue_use()
413 */
414int snd_seq_queue_timer_open(int queueid)
415{
416 int result = 0;
417 struct snd_seq_queue *queue;
418 struct snd_seq_timer *tmr;
419
420 queue = queueptr(queueid);
421 if (queue == NULL)
422 return -EINVAL;
423 tmr = queue->timer;
424 result = snd_seq_timer_open(queue);
425 if (result < 0) {
426 snd_seq_timer_defaults(tmr);
427 result = snd_seq_timer_open(queue);
428 }
429 queuefree(queue);
430 return result;
431}
432
433/* close timer -
434 * q->use mutex should be down before calling this function
435 */
436int snd_seq_queue_timer_close(int queueid)
437{
438 struct snd_seq_queue *queue;
439 int result = 0;
440
441 queue = queueptr(queueid);
442 if (queue == NULL)
443 return -EINVAL;
444 snd_seq_timer_close(queue);
445 queuefree(queue);
446 return result;
447}
448
449/* change queue tempo and ppq */
450int snd_seq_queue_timer_set_tempo(int queueid, int client,
451 struct snd_seq_queue_tempo *info)
452{
453 struct snd_seq_queue *q = queueptr(queueid);
454 int result;
455
456 if (q == NULL)
457 return -EINVAL;
458 if (! queue_access_lock(q, client)) {
459 queuefree(q);
460 return -EPERM;
461 }
462
463 result = snd_seq_timer_set_tempo_ppq(q->timer, info->tempo, info->ppq);
464 if (result >= 0 && info->skew_base > 0)
465 result = snd_seq_timer_set_skew(q->timer, info->skew_value,
466 info->skew_base);
467 queue_access_unlock(q);
468 queuefree(q);
469 return result;
470}
471
472/* use or unuse this queue */
473static void queue_use(struct snd_seq_queue *queue, int client, int use)
474{
475 if (use) {
476 if (!test_and_set_bit(client, queue->clients_bitmap))
477 queue->clients++;
478 } else {
479 if (test_and_clear_bit(client, queue->clients_bitmap))
480 queue->clients--;
481 }
482 if (queue->clients) {
483 if (use && queue->clients == 1)
484 snd_seq_timer_defaults(queue->timer);
485 snd_seq_timer_open(queue);
486 } else {
487 snd_seq_timer_close(queue);
488 }
489}
490
491/* use or unuse this queue -
492 * if it is the first client, starts the timer.
493 * if it is not longer used by any clients, stop the timer.
494 */
495int snd_seq_queue_use(int queueid, int client, int use)
496{
497 struct snd_seq_queue *queue;
498
499 queue = queueptr(queueid);
500 if (queue == NULL)
501 return -EINVAL;
502 mutex_lock(&queue->timer_mutex);
503 queue_use(queue, client, use);
504 mutex_unlock(&queue->timer_mutex);
505 queuefree(queue);
506 return 0;
507}
508
509/*
510 * check if queue is used by the client
511 * return negative value if the queue is invalid.
512 * return 0 if not used, 1 if used.
513 */
514int snd_seq_queue_is_used(int queueid, int client)
515{
516 struct snd_seq_queue *q;
517 int result;
518
519 q = queueptr(queueid);
520 if (q == NULL)
521 return -EINVAL; /* invalid queue */
522 result = test_bit(client, q->clients_bitmap) ? 1 : 0;
523 queuefree(q);
524 return result;
525}
526
527
528/*----------------------------------------------------------------*/
529
530/* final stage notification -
531 * remove cells for no longer exist client (for non-owned queue)
532 * or delete this queue (for owned queue)
533 */
534void snd_seq_queue_client_leave(int client)
535{
536 int i;
537 struct snd_seq_queue *q;
538
539 /* delete own queues from queue list */
540 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
541 q = queue_list_remove(i, client);
542 if (q)
543 queue_delete(q);
544 }
545
546 /* remove cells from existing queues -
547 * they are not owned by this client
548 */
549 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
550 q = queueptr(i);
551 if (!q)
552 continue;
553 if (test_bit(client, q->clients_bitmap)) {
554 snd_seq_prioq_leave(q->tickq, client, 0);
555 snd_seq_prioq_leave(q->timeq, client, 0);
556 snd_seq_queue_use(q->queue, client, 0);
557 }
558 queuefree(q);
559 }
560}
561
562
563
564/*----------------------------------------------------------------*/
565
566/* remove cells from all queues */
567void snd_seq_queue_client_leave_cells(int client)
568{
569 int i;
570 struct snd_seq_queue *q;
571
572 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
573 q = queueptr(i);
574 if (!q)
575 continue;
576 snd_seq_prioq_leave(q->tickq, client, 0);
577 snd_seq_prioq_leave(q->timeq, client, 0);
578 queuefree(q);
579 }
580}
581
582/* remove cells based on flush criteria */
583void snd_seq_queue_remove_cells(int client, struct snd_seq_remove_events *info)
584{
585 int i;
586 struct snd_seq_queue *q;
587
588 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
589 q = queueptr(i);
590 if (!q)
591 continue;
592 if (test_bit(client, q->clients_bitmap) &&
593 (! (info->remove_mode & SNDRV_SEQ_REMOVE_DEST) ||
594 q->queue == info->queue)) {
595 snd_seq_prioq_remove_events(q->tickq, client, info);
596 snd_seq_prioq_remove_events(q->timeq, client, info);
597 }
598 queuefree(q);
599 }
600}
601
602/*----------------------------------------------------------------*/
603
604/*
605 * send events to all subscribed ports
606 */
607static void queue_broadcast_event(struct snd_seq_queue *q, struct snd_seq_event *ev,
608 int atomic, int hop)
609{
610 struct snd_seq_event sev;
611
612 sev = *ev;
613
614 sev.flags = SNDRV_SEQ_TIME_STAMP_TICK|SNDRV_SEQ_TIME_MODE_ABS;
615 sev.time.tick = q->timer->tick.cur_tick;
616 sev.queue = q->queue;
617 sev.data.queue.queue = q->queue;
618
619 /* broadcast events from Timer port */
620 sev.source.client = SNDRV_SEQ_CLIENT_SYSTEM;
621 sev.source.port = SNDRV_SEQ_PORT_SYSTEM_TIMER;
622 sev.dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS;
623 snd_seq_kernel_client_dispatch(SNDRV_SEQ_CLIENT_SYSTEM, &sev, atomic, hop);
624}
625
626/*
627 * process a received queue-control event.
628 * this function is exported for seq_sync.c.
629 */
630static void snd_seq_queue_process_event(struct snd_seq_queue *q,
631 struct snd_seq_event *ev,
632 int atomic, int hop)
633{
634 switch (ev->type) {
635 case SNDRV_SEQ_EVENT_START:
636 snd_seq_prioq_leave(q->tickq, ev->source.client, 1);
637 snd_seq_prioq_leave(q->timeq, ev->source.client, 1);
638 if (! snd_seq_timer_start(q->timer))
639 queue_broadcast_event(q, ev, atomic, hop);
640 break;
641
642 case SNDRV_SEQ_EVENT_CONTINUE:
643 if (! snd_seq_timer_continue(q->timer))
644 queue_broadcast_event(q, ev, atomic, hop);
645 break;
646
647 case SNDRV_SEQ_EVENT_STOP:
648 snd_seq_timer_stop(q->timer);
649 queue_broadcast_event(q, ev, atomic, hop);
650 break;
651
652 case SNDRV_SEQ_EVENT_TEMPO:
653 snd_seq_timer_set_tempo(q->timer, ev->data.queue.param.value);
654 queue_broadcast_event(q, ev, atomic, hop);
655 break;
656
657 case SNDRV_SEQ_EVENT_SETPOS_TICK:
658 if (snd_seq_timer_set_position_tick(q->timer, ev->data.queue.param.time.tick) == 0) {
659 queue_broadcast_event(q, ev, atomic, hop);
660 }
661 break;
662
663 case SNDRV_SEQ_EVENT_SETPOS_TIME:
664 if (snd_seq_timer_set_position_time(q->timer, ev->data.queue.param.time.time) == 0) {
665 queue_broadcast_event(q, ev, atomic, hop);
666 }
667 break;
668 case SNDRV_SEQ_EVENT_QUEUE_SKEW:
669 if (snd_seq_timer_set_skew(q->timer,
670 ev->data.queue.param.skew.value,
671 ev->data.queue.param.skew.base) == 0) {
672 queue_broadcast_event(q, ev, atomic, hop);
673 }
674 break;
675 }
676}
677
678
679/*
680 * Queue control via timer control port:
681 * this function is exported as a callback of timer port.
682 */
683int snd_seq_control_queue(struct snd_seq_event *ev, int atomic, int hop)
684{
685 struct snd_seq_queue *q;
686
687 if (snd_BUG_ON(!ev))
688 return -EINVAL;
689 q = queueptr(ev->data.queue.queue);
690
691 if (q == NULL)
692 return -EINVAL;
693
694 if (! queue_access_lock(q, ev->source.client)) {
695 queuefree(q);
696 return -EPERM;
697 }
698
699 snd_seq_queue_process_event(q, ev, atomic, hop);
700
701 queue_access_unlock(q);
702 queuefree(q);
703 return 0;
704}
705
706
707/*----------------------------------------------------------------*/
708
709#ifdef CONFIG_SND_PROC_FS
710/* exported to seq_info.c */
711void snd_seq_info_queues_read(struct snd_info_entry *entry,
712 struct snd_info_buffer *buffer)
713{
714 int i, bpm;
715 struct snd_seq_queue *q;
716 struct snd_seq_timer *tmr;
717 bool locked;
718 int owner;
719
720 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
721 q = queueptr(i);
722 if (!q)
723 continue;
724
725 tmr = q->timer;
726 if (tmr->tempo)
727 bpm = 60000000 / tmr->tempo;
728 else
729 bpm = 0;
730
731 scoped_guard(spinlock_irq, &q->owner_lock) {
732 locked = q->locked;
733 owner = q->owner;
734 }
735
736 snd_iprintf(buffer, "queue %d: [%s]\n", q->queue, q->name);
737 snd_iprintf(buffer, "owned by client : %d\n", owner);
738 snd_iprintf(buffer, "lock status : %s\n", locked ? "Locked" : "Free");
739 snd_iprintf(buffer, "queued time events : %d\n", snd_seq_prioq_avail(q->timeq));
740 snd_iprintf(buffer, "queued tick events : %d\n", snd_seq_prioq_avail(q->tickq));
741 snd_iprintf(buffer, "timer state : %s\n", tmr->running ? "Running" : "Stopped");
742 snd_iprintf(buffer, "timer PPQ : %d\n", tmr->ppq);
743 snd_iprintf(buffer, "current tempo : %d\n", tmr->tempo);
744 snd_iprintf(buffer, "current BPM : %d\n", bpm);
745 snd_iprintf(buffer, "current time : %d.%09d s\n", tmr->cur_time.tv_sec, tmr->cur_time.tv_nsec);
746 snd_iprintf(buffer, "current tick : %d\n", tmr->tick.cur_tick);
747 snd_iprintf(buffer, "\n");
748 queuefree(q);
749 }
750}
751#endif /* CONFIG_SND_PROC_FS */
752