xref: /openbmc/linux/sound/core/seq/seq_queue.c (revision 8dde5715)
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 */
37 static struct snd_seq_queue *queue_list[SNDRV_SEQ_MAX_QUEUES];
38 static DEFINE_SPINLOCK(queue_list_lock);
39 /* number of queues allocated */
40 static int num_queues;
41 
42 int snd_seq_queue_get_cur_queues(void)
43 {
44 	return num_queues;
45 }
46 
47 /*----------------------------------------------------------------*/
48 
49 /* assign queue id and insert to list */
50 static 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 
69 static 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) */
96 static 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) */
129 static 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 */
150 void 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 
161 static 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  */
168 struct 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 */
187 int 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 */
203 struct 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 */
219 struct 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 		if ((q = queueptr(i)) != NULL) {
226 			if (strncmp(q->name, name, sizeof(q->name)) == 0)
227 				return q;
228 			queuefree(q);
229 		}
230 	}
231 	return NULL;
232 }
233 
234 
235 /* -------------------------------------------------------- */
236 
237 void snd_seq_check_queue(struct snd_seq_queue *q, int atomic, int hop)
238 {
239 	unsigned long flags;
240 	struct snd_seq_event_cell *cell;
241 
242 	if (q == NULL)
243 		return;
244 
245 	/* make this function non-reentrant */
246 	spin_lock_irqsave(&q->check_lock, flags);
247 	if (q->check_blocked) {
248 		q->check_again = 1;
249 		spin_unlock_irqrestore(&q->check_lock, flags);
250 		return;		/* other thread is already checking queues */
251 	}
252 	q->check_blocked = 1;
253 	spin_unlock_irqrestore(&q->check_lock, flags);
254 
255       __again:
256 	/* Process tick queue... */
257 	for (;;) {
258 		cell = snd_seq_prioq_cell_out(q->tickq,
259 					      &q->timer->tick.cur_tick);
260 		if (!cell)
261 			break;
262 		snd_seq_dispatch_event(cell, atomic, hop);
263 	}
264 
265 	/* Process time queue... */
266 	for (;;) {
267 		cell = snd_seq_prioq_cell_out(q->timeq, &q->timer->cur_time);
268 		if (!cell)
269 			break;
270 		snd_seq_dispatch_event(cell, atomic, hop);
271 	}
272 
273 	/* free lock */
274 	spin_lock_irqsave(&q->check_lock, flags);
275 	if (q->check_again) {
276 		q->check_again = 0;
277 		spin_unlock_irqrestore(&q->check_lock, flags);
278 		goto __again;
279 	}
280 	q->check_blocked = 0;
281 	spin_unlock_irqrestore(&q->check_lock, flags);
282 }
283 
284 
285 /* enqueue a event to singe queue */
286 int 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 
340 static 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  */
348 static int queue_access_lock(struct snd_seq_queue *q, int client)
349 {
350 	unsigned long flags;
351 	int access_ok;
352 
353 	spin_lock_irqsave(&q->owner_lock, flags);
354 	access_ok = check_access(q, client);
355 	if (access_ok)
356 		q->klocked = 1;
357 	spin_unlock_irqrestore(&q->owner_lock, flags);
358 	return access_ok;
359 }
360 
361 /* unlock the queue */
362 static inline void queue_access_unlock(struct snd_seq_queue *q)
363 {
364 	unsigned long flags;
365 
366 	spin_lock_irqsave(&q->owner_lock, flags);
367 	q->klocked = 0;
368 	spin_unlock_irqrestore(&q->owner_lock, flags);
369 }
370 
371 /* exported - only checking permission */
372 int snd_seq_queue_check_access(int queueid, int client)
373 {
374 	struct snd_seq_queue *q = queueptr(queueid);
375 	int access_ok;
376 	unsigned long flags;
377 
378 	if (! q)
379 		return 0;
380 	spin_lock_irqsave(&q->owner_lock, flags);
381 	access_ok = check_access(q, client);
382 	spin_unlock_irqrestore(&q->owner_lock, flags);
383 	queuefree(q);
384 	return access_ok;
385 }
386 
387 /*----------------------------------------------------------------*/
388 
389 /*
390  * change queue's owner and permission
391  */
392 int snd_seq_queue_set_owner(int queueid, int client, int locked)
393 {
394 	struct snd_seq_queue *q = queueptr(queueid);
395 
396 	if (q == NULL)
397 		return -EINVAL;
398 
399 	if (! queue_access_lock(q, client)) {
400 		queuefree(q);
401 		return -EPERM;
402 	}
403 
404 	q->locked = locked ? 1 : 0;
405 	q->owner = client;
406 	queue_access_unlock(q);
407 	queuefree(q);
408 
409 	return 0;
410 }
411 
412 
413 /*----------------------------------------------------------------*/
414 
415 /* open timer -
416  * q->use mutex should be down before calling this function to avoid
417  * confliction with snd_seq_queue_use()
418  */
419 int snd_seq_queue_timer_open(int queueid)
420 {
421 	int result = 0;
422 	struct snd_seq_queue *queue;
423 	struct snd_seq_timer *tmr;
424 
425 	queue = queueptr(queueid);
426 	if (queue == NULL)
427 		return -EINVAL;
428 	tmr = queue->timer;
429 	if ((result = snd_seq_timer_open(queue)) < 0) {
430 		snd_seq_timer_defaults(tmr);
431 		result = snd_seq_timer_open(queue);
432 	}
433 	queuefree(queue);
434 	return result;
435 }
436 
437 /* close timer -
438  * q->use mutex should be down before calling this function
439  */
440 int snd_seq_queue_timer_close(int queueid)
441 {
442 	struct snd_seq_queue *queue;
443 	int result = 0;
444 
445 	queue = queueptr(queueid);
446 	if (queue == NULL)
447 		return -EINVAL;
448 	snd_seq_timer_close(queue);
449 	queuefree(queue);
450 	return result;
451 }
452 
453 /* change queue tempo and ppq */
454 int snd_seq_queue_timer_set_tempo(int queueid, int client,
455 				  struct snd_seq_queue_tempo *info)
456 {
457 	struct snd_seq_queue *q = queueptr(queueid);
458 	int result;
459 
460 	if (q == NULL)
461 		return -EINVAL;
462 	if (! queue_access_lock(q, client)) {
463 		queuefree(q);
464 		return -EPERM;
465 	}
466 
467 	result = snd_seq_timer_set_tempo_ppq(q->timer, info->tempo, info->ppq);
468 	if (result >= 0 && info->skew_base > 0)
469 		result = snd_seq_timer_set_skew(q->timer, info->skew_value,
470 						info->skew_base);
471 	queue_access_unlock(q);
472 	queuefree(q);
473 	return result;
474 }
475 
476 /* use or unuse this queue */
477 static void queue_use(struct snd_seq_queue *queue, int client, int use)
478 {
479 	if (use) {
480 		if (!test_and_set_bit(client, queue->clients_bitmap))
481 			queue->clients++;
482 	} else {
483 		if (test_and_clear_bit(client, queue->clients_bitmap))
484 			queue->clients--;
485 	}
486 	if (queue->clients) {
487 		if (use && queue->clients == 1)
488 			snd_seq_timer_defaults(queue->timer);
489 		snd_seq_timer_open(queue);
490 	} else {
491 		snd_seq_timer_close(queue);
492 	}
493 }
494 
495 /* use or unuse this queue -
496  * if it is the first client, starts the timer.
497  * if it is not longer used by any clients, stop the timer.
498  */
499 int snd_seq_queue_use(int queueid, int client, int use)
500 {
501 	struct snd_seq_queue *queue;
502 
503 	queue = queueptr(queueid);
504 	if (queue == NULL)
505 		return -EINVAL;
506 	mutex_lock(&queue->timer_mutex);
507 	queue_use(queue, client, use);
508 	mutex_unlock(&queue->timer_mutex);
509 	queuefree(queue);
510 	return 0;
511 }
512 
513 /*
514  * check if queue is used by the client
515  * return negative value if the queue is invalid.
516  * return 0 if not used, 1 if used.
517  */
518 int snd_seq_queue_is_used(int queueid, int client)
519 {
520 	struct snd_seq_queue *q;
521 	int result;
522 
523 	q = queueptr(queueid);
524 	if (q == NULL)
525 		return -EINVAL; /* invalid queue */
526 	result = test_bit(client, q->clients_bitmap) ? 1 : 0;
527 	queuefree(q);
528 	return result;
529 }
530 
531 
532 /*----------------------------------------------------------------*/
533 
534 /* notification that client has left the system -
535  * stop the timer on all queues owned by this client
536  */
537 void snd_seq_queue_client_termination(int client)
538 {
539 	unsigned long flags;
540 	int i;
541 	struct snd_seq_queue *q;
542 
543 	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
544 		if ((q = queueptr(i)) == NULL)
545 			continue;
546 		spin_lock_irqsave(&q->owner_lock, flags);
547 		if (q->owner == client)
548 			q->klocked = 1;
549 		spin_unlock_irqrestore(&q->owner_lock, flags);
550 		if (q->owner == client) {
551 			if (q->timer->running)
552 				snd_seq_timer_stop(q->timer);
553 			snd_seq_timer_reset(q->timer);
554 		}
555 		queuefree(q);
556 	}
557 }
558 
559 /* final stage notification -
560  * remove cells for no longer exist client (for non-owned queue)
561  * or delete this queue (for owned queue)
562  */
563 void snd_seq_queue_client_leave(int client)
564 {
565 	int i;
566 	struct snd_seq_queue *q;
567 
568 	/* delete own queues from queue list */
569 	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
570 		if ((q = queue_list_remove(i, client)) != NULL)
571 			queue_delete(q);
572 	}
573 
574 	/* remove cells from existing queues -
575 	 * they are not owned by this client
576 	 */
577 	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
578 		if ((q = queueptr(i)) == NULL)
579 			continue;
580 		if (test_bit(client, q->clients_bitmap)) {
581 			snd_seq_prioq_leave(q->tickq, client, 0);
582 			snd_seq_prioq_leave(q->timeq, client, 0);
583 			snd_seq_queue_use(q->queue, client, 0);
584 		}
585 		queuefree(q);
586 	}
587 }
588 
589 
590 
591 /*----------------------------------------------------------------*/
592 
593 /* remove cells from all queues */
594 void snd_seq_queue_client_leave_cells(int client)
595 {
596 	int i;
597 	struct snd_seq_queue *q;
598 
599 	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
600 		if ((q = queueptr(i)) == NULL)
601 			continue;
602 		snd_seq_prioq_leave(q->tickq, client, 0);
603 		snd_seq_prioq_leave(q->timeq, client, 0);
604 		queuefree(q);
605 	}
606 }
607 
608 /* remove cells based on flush criteria */
609 void snd_seq_queue_remove_cells(int client, struct snd_seq_remove_events *info)
610 {
611 	int i;
612 	struct snd_seq_queue *q;
613 
614 	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
615 		if ((q = queueptr(i)) == NULL)
616 			continue;
617 		if (test_bit(client, q->clients_bitmap) &&
618 		    (! (info->remove_mode & SNDRV_SEQ_REMOVE_DEST) ||
619 		     q->queue == info->queue)) {
620 			snd_seq_prioq_remove_events(q->tickq, client, info);
621 			snd_seq_prioq_remove_events(q->timeq, client, info);
622 		}
623 		queuefree(q);
624 	}
625 }
626 
627 /*----------------------------------------------------------------*/
628 
629 /*
630  * send events to all subscribed ports
631  */
632 static void queue_broadcast_event(struct snd_seq_queue *q, struct snd_seq_event *ev,
633 				  int atomic, int hop)
634 {
635 	struct snd_seq_event sev;
636 
637 	sev = *ev;
638 
639 	sev.flags = SNDRV_SEQ_TIME_STAMP_TICK|SNDRV_SEQ_TIME_MODE_ABS;
640 	sev.time.tick = q->timer->tick.cur_tick;
641 	sev.queue = q->queue;
642 	sev.data.queue.queue = q->queue;
643 
644 	/* broadcast events from Timer port */
645 	sev.source.client = SNDRV_SEQ_CLIENT_SYSTEM;
646 	sev.source.port = SNDRV_SEQ_PORT_SYSTEM_TIMER;
647 	sev.dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS;
648 	snd_seq_kernel_client_dispatch(SNDRV_SEQ_CLIENT_SYSTEM, &sev, atomic, hop);
649 }
650 
651 /*
652  * process a received queue-control event.
653  * this function is exported for seq_sync.c.
654  */
655 static void snd_seq_queue_process_event(struct snd_seq_queue *q,
656 					struct snd_seq_event *ev,
657 					int atomic, int hop)
658 {
659 	switch (ev->type) {
660 	case SNDRV_SEQ_EVENT_START:
661 		snd_seq_prioq_leave(q->tickq, ev->source.client, 1);
662 		snd_seq_prioq_leave(q->timeq, ev->source.client, 1);
663 		if (! snd_seq_timer_start(q->timer))
664 			queue_broadcast_event(q, ev, atomic, hop);
665 		break;
666 
667 	case SNDRV_SEQ_EVENT_CONTINUE:
668 		if (! snd_seq_timer_continue(q->timer))
669 			queue_broadcast_event(q, ev, atomic, hop);
670 		break;
671 
672 	case SNDRV_SEQ_EVENT_STOP:
673 		snd_seq_timer_stop(q->timer);
674 		queue_broadcast_event(q, ev, atomic, hop);
675 		break;
676 
677 	case SNDRV_SEQ_EVENT_TEMPO:
678 		snd_seq_timer_set_tempo(q->timer, ev->data.queue.param.value);
679 		queue_broadcast_event(q, ev, atomic, hop);
680 		break;
681 
682 	case SNDRV_SEQ_EVENT_SETPOS_TICK:
683 		if (snd_seq_timer_set_position_tick(q->timer, ev->data.queue.param.time.tick) == 0) {
684 			queue_broadcast_event(q, ev, atomic, hop);
685 		}
686 		break;
687 
688 	case SNDRV_SEQ_EVENT_SETPOS_TIME:
689 		if (snd_seq_timer_set_position_time(q->timer, ev->data.queue.param.time.time) == 0) {
690 			queue_broadcast_event(q, ev, atomic, hop);
691 		}
692 		break;
693 	case SNDRV_SEQ_EVENT_QUEUE_SKEW:
694 		if (snd_seq_timer_set_skew(q->timer,
695 					   ev->data.queue.param.skew.value,
696 					   ev->data.queue.param.skew.base) == 0) {
697 			queue_broadcast_event(q, ev, atomic, hop);
698 		}
699 		break;
700 	}
701 }
702 
703 
704 /*
705  * Queue control via timer control port:
706  * this function is exported as a callback of timer port.
707  */
708 int snd_seq_control_queue(struct snd_seq_event *ev, int atomic, int hop)
709 {
710 	struct snd_seq_queue *q;
711 
712 	if (snd_BUG_ON(!ev))
713 		return -EINVAL;
714 	q = queueptr(ev->data.queue.queue);
715 
716 	if (q == NULL)
717 		return -EINVAL;
718 
719 	if (! queue_access_lock(q, ev->source.client)) {
720 		queuefree(q);
721 		return -EPERM;
722 	}
723 
724 	snd_seq_queue_process_event(q, ev, atomic, hop);
725 
726 	queue_access_unlock(q);
727 	queuefree(q);
728 	return 0;
729 }
730 
731 
732 /*----------------------------------------------------------------*/
733 
734 #ifdef CONFIG_SND_PROC_FS
735 /* exported to seq_info.c */
736 void snd_seq_info_queues_read(struct snd_info_entry *entry,
737 			      struct snd_info_buffer *buffer)
738 {
739 	int i, bpm;
740 	struct snd_seq_queue *q;
741 	struct snd_seq_timer *tmr;
742 
743 	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
744 		if ((q = queueptr(i)) == NULL)
745 			continue;
746 
747 		tmr = q->timer;
748 		if (tmr->tempo)
749 			bpm = 60000000 / tmr->tempo;
750 		else
751 			bpm = 0;
752 
753 		snd_iprintf(buffer, "queue %d: [%s]\n", q->queue, q->name);
754 		snd_iprintf(buffer, "owned by client    : %d\n", q->owner);
755 		snd_iprintf(buffer, "lock status        : %s\n", q->locked ? "Locked" : "Free");
756 		snd_iprintf(buffer, "queued time events : %d\n", snd_seq_prioq_avail(q->timeq));
757 		snd_iprintf(buffer, "queued tick events : %d\n", snd_seq_prioq_avail(q->tickq));
758 		snd_iprintf(buffer, "timer state        : %s\n", tmr->running ? "Running" : "Stopped");
759 		snd_iprintf(buffer, "timer PPQ          : %d\n", tmr->ppq);
760 		snd_iprintf(buffer, "current tempo      : %d\n", tmr->tempo);
761 		snd_iprintf(buffer, "current BPM        : %d\n", bpm);
762 		snd_iprintf(buffer, "current time       : %d.%09d s\n", tmr->cur_time.tv_sec, tmr->cur_time.tv_nsec);
763 		snd_iprintf(buffer, "current tick       : %d\n", tmr->tick.cur_tick);
764 		snd_iprintf(buffer, "\n");
765 		queuefree(q);
766 	}
767 }
768 #endif /* CONFIG_SND_PROC_FS */
769 
770