xref: /linux/sound/core/seq/seq_queue.c (revision a1ff5a7d78a036d6c2178ee5acd6ba4946243800)
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 
snd_seq_queue_get_cur_queues(void)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 */
queue_list_add(struct snd_seq_queue * q)50 static 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 
queue_list_remove(int id,int client)66 static 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) */
queue_new(int owner,int locked)88 static 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) */
queue_delete(struct snd_seq_queue * q)121 static 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 */
snd_seq_queues_delete(void)142 void 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 
153 static 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  */
snd_seq_queue_alloc(int client,int locked,unsigned int info_flags)160 struct 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 */
snd_seq_queue_delete(int client,int queueid)179 int 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 */
queueptr(int queueid)195 struct 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 */
snd_seq_queue_find_name(char * name)209 struct 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 
snd_seq_check_queue(struct snd_seq_queue * q,int atomic,int hop)230 void 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 */
snd_seq_enqueue_event(struct snd_seq_event_cell * cell,int atomic,int hop)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 
check_access(struct snd_seq_queue * q,int client)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  */
queue_access_lock(struct snd_seq_queue * q,int client)348 static 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 */
queue_access_unlock(struct snd_seq_queue * q)360 static 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 */
snd_seq_queue_check_access(int queueid,int client)367 int 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  */
snd_seq_queue_set_owner(int queueid,int client,int locked)385 int 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  */
snd_seq_queue_timer_open(int queueid)414 int 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  */
snd_seq_queue_timer_close(int queueid)436 int 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 */
snd_seq_queue_timer_set_tempo(int queueid,int client,struct snd_seq_queue_tempo * info)450 int 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 					     info->tempo_base);
465 	if (result >= 0 && info->skew_base > 0)
466 		result = snd_seq_timer_set_skew(q->timer, info->skew_value,
467 						info->skew_base);
468 	queue_access_unlock(q);
469 	queuefree(q);
470 	return result;
471 }
472 
473 /* use or unuse this queue */
queue_use(struct snd_seq_queue * queue,int client,int use)474 static void queue_use(struct snd_seq_queue *queue, int client, int use)
475 {
476 	if (use) {
477 		if (!test_and_set_bit(client, queue->clients_bitmap))
478 			queue->clients++;
479 	} else {
480 		if (test_and_clear_bit(client, queue->clients_bitmap))
481 			queue->clients--;
482 	}
483 	if (queue->clients) {
484 		if (use && queue->clients == 1)
485 			snd_seq_timer_defaults(queue->timer);
486 		snd_seq_timer_open(queue);
487 	} else {
488 		snd_seq_timer_close(queue);
489 	}
490 }
491 
492 /* use or unuse this queue -
493  * if it is the first client, starts the timer.
494  * if it is not longer used by any clients, stop the timer.
495  */
snd_seq_queue_use(int queueid,int client,int use)496 int snd_seq_queue_use(int queueid, int client, int use)
497 {
498 	struct snd_seq_queue *queue;
499 
500 	queue = queueptr(queueid);
501 	if (queue == NULL)
502 		return -EINVAL;
503 	mutex_lock(&queue->timer_mutex);
504 	queue_use(queue, client, use);
505 	mutex_unlock(&queue->timer_mutex);
506 	queuefree(queue);
507 	return 0;
508 }
509 
510 /*
511  * check if queue is used by the client
512  * return negative value if the queue is invalid.
513  * return 0 if not used, 1 if used.
514  */
snd_seq_queue_is_used(int queueid,int client)515 int snd_seq_queue_is_used(int queueid, int client)
516 {
517 	struct snd_seq_queue *q;
518 	int result;
519 
520 	q = queueptr(queueid);
521 	if (q == NULL)
522 		return -EINVAL; /* invalid queue */
523 	result = test_bit(client, q->clients_bitmap) ? 1 : 0;
524 	queuefree(q);
525 	return result;
526 }
527 
528 
529 /*----------------------------------------------------------------*/
530 
531 /* final stage notification -
532  * remove cells for no longer exist client (for non-owned queue)
533  * or delete this queue (for owned queue)
534  */
snd_seq_queue_client_leave(int client)535 void snd_seq_queue_client_leave(int client)
536 {
537 	int i;
538 	struct snd_seq_queue *q;
539 
540 	/* delete own queues from queue list */
541 	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
542 		q = queue_list_remove(i, client);
543 		if (q)
544 			queue_delete(q);
545 	}
546 
547 	/* remove cells from existing queues -
548 	 * they are not owned by this client
549 	 */
550 	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
551 		q = queueptr(i);
552 		if (!q)
553 			continue;
554 		if (test_bit(client, q->clients_bitmap)) {
555 			snd_seq_prioq_leave(q->tickq, client, 0);
556 			snd_seq_prioq_leave(q->timeq, client, 0);
557 			snd_seq_queue_use(q->queue, client, 0);
558 		}
559 		queuefree(q);
560 	}
561 }
562 
563 
564 
565 /*----------------------------------------------------------------*/
566 
567 /* remove cells from all queues */
snd_seq_queue_client_leave_cells(int client)568 void snd_seq_queue_client_leave_cells(int client)
569 {
570 	int i;
571 	struct snd_seq_queue *q;
572 
573 	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
574 		q = queueptr(i);
575 		if (!q)
576 			continue;
577 		snd_seq_prioq_leave(q->tickq, client, 0);
578 		snd_seq_prioq_leave(q->timeq, client, 0);
579 		queuefree(q);
580 	}
581 }
582 
583 /* remove cells based on flush criteria */
snd_seq_queue_remove_cells(int client,struct snd_seq_remove_events * info)584 void snd_seq_queue_remove_cells(int client, struct snd_seq_remove_events *info)
585 {
586 	int i;
587 	struct snd_seq_queue *q;
588 
589 	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
590 		q = queueptr(i);
591 		if (!q)
592 			continue;
593 		if (test_bit(client, q->clients_bitmap) &&
594 		    (! (info->remove_mode & SNDRV_SEQ_REMOVE_DEST) ||
595 		     q->queue == info->queue)) {
596 			snd_seq_prioq_remove_events(q->tickq, client, info);
597 			snd_seq_prioq_remove_events(q->timeq, client, info);
598 		}
599 		queuefree(q);
600 	}
601 }
602 
603 /*----------------------------------------------------------------*/
604 
605 /*
606  * send events to all subscribed ports
607  */
queue_broadcast_event(struct snd_seq_queue * q,struct snd_seq_event * ev,int atomic,int hop)608 static void queue_broadcast_event(struct snd_seq_queue *q, struct snd_seq_event *ev,
609 				  int atomic, int hop)
610 {
611 	struct snd_seq_event sev;
612 
613 	sev = *ev;
614 
615 	sev.flags = SNDRV_SEQ_TIME_STAMP_TICK|SNDRV_SEQ_TIME_MODE_ABS;
616 	sev.time.tick = q->timer->tick.cur_tick;
617 	sev.queue = q->queue;
618 	sev.data.queue.queue = q->queue;
619 
620 	/* broadcast events from Timer port */
621 	sev.source.client = SNDRV_SEQ_CLIENT_SYSTEM;
622 	sev.source.port = SNDRV_SEQ_PORT_SYSTEM_TIMER;
623 	sev.dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS;
624 	snd_seq_kernel_client_dispatch(SNDRV_SEQ_CLIENT_SYSTEM, &sev, atomic, hop);
625 }
626 
627 /*
628  * process a received queue-control event.
629  * this function is exported for seq_sync.c.
630  */
snd_seq_queue_process_event(struct snd_seq_queue * q,struct snd_seq_event * ev,int atomic,int hop)631 static void snd_seq_queue_process_event(struct snd_seq_queue *q,
632 					struct snd_seq_event *ev,
633 					int atomic, int hop)
634 {
635 	switch (ev->type) {
636 	case SNDRV_SEQ_EVENT_START:
637 		snd_seq_prioq_leave(q->tickq, ev->source.client, 1);
638 		snd_seq_prioq_leave(q->timeq, ev->source.client, 1);
639 		if (! snd_seq_timer_start(q->timer))
640 			queue_broadcast_event(q, ev, atomic, hop);
641 		break;
642 
643 	case SNDRV_SEQ_EVENT_CONTINUE:
644 		if (! snd_seq_timer_continue(q->timer))
645 			queue_broadcast_event(q, ev, atomic, hop);
646 		break;
647 
648 	case SNDRV_SEQ_EVENT_STOP:
649 		snd_seq_timer_stop(q->timer);
650 		queue_broadcast_event(q, ev, atomic, hop);
651 		break;
652 
653 	case SNDRV_SEQ_EVENT_TEMPO:
654 		snd_seq_timer_set_tempo(q->timer, ev->data.queue.param.value);
655 		queue_broadcast_event(q, ev, atomic, hop);
656 		break;
657 
658 	case SNDRV_SEQ_EVENT_SETPOS_TICK:
659 		if (snd_seq_timer_set_position_tick(q->timer, ev->data.queue.param.time.tick) == 0) {
660 			queue_broadcast_event(q, ev, atomic, hop);
661 		}
662 		break;
663 
664 	case SNDRV_SEQ_EVENT_SETPOS_TIME:
665 		if (snd_seq_timer_set_position_time(q->timer, ev->data.queue.param.time.time) == 0) {
666 			queue_broadcast_event(q, ev, atomic, hop);
667 		}
668 		break;
669 	case SNDRV_SEQ_EVENT_QUEUE_SKEW:
670 		if (snd_seq_timer_set_skew(q->timer,
671 					   ev->data.queue.param.skew.value,
672 					   ev->data.queue.param.skew.base) == 0) {
673 			queue_broadcast_event(q, ev, atomic, hop);
674 		}
675 		break;
676 	}
677 }
678 
679 
680 /*
681  * Queue control via timer control port:
682  * this function is exported as a callback of timer port.
683  */
snd_seq_control_queue(struct snd_seq_event * ev,int atomic,int hop)684 int snd_seq_control_queue(struct snd_seq_event *ev, int atomic, int hop)
685 {
686 	struct snd_seq_queue *q;
687 
688 	if (snd_BUG_ON(!ev))
689 		return -EINVAL;
690 	q = queueptr(ev->data.queue.queue);
691 
692 	if (q == NULL)
693 		return -EINVAL;
694 
695 	if (! queue_access_lock(q, ev->source.client)) {
696 		queuefree(q);
697 		return -EPERM;
698 	}
699 
700 	snd_seq_queue_process_event(q, ev, atomic, hop);
701 
702 	queue_access_unlock(q);
703 	queuefree(q);
704 	return 0;
705 }
706 
707 
708 /*----------------------------------------------------------------*/
709 
710 #ifdef CONFIG_SND_PROC_FS
711 /* exported to seq_info.c */
snd_seq_info_queues_read(struct snd_info_entry * entry,struct snd_info_buffer * buffer)712 void snd_seq_info_queues_read(struct snd_info_entry *entry,
713 			      struct snd_info_buffer *buffer)
714 {
715 	int i, bpm;
716 	struct snd_seq_queue *q;
717 	struct snd_seq_timer *tmr;
718 	bool locked;
719 	int owner;
720 
721 	for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
722 		q = queueptr(i);
723 		if (!q)
724 			continue;
725 
726 		tmr = q->timer;
727 		if (tmr->tempo)
728 			bpm = (60000 * tmr->tempo_base) / tmr->tempo;
729 		else
730 			bpm = 0;
731 
732 		scoped_guard(spinlock_irq, &q->owner_lock) {
733 			locked = q->locked;
734 			owner = q->owner;
735 		}
736 
737 		snd_iprintf(buffer, "queue %d: [%s]\n", q->queue, q->name);
738 		snd_iprintf(buffer, "owned by client    : %d\n", owner);
739 		snd_iprintf(buffer, "lock status        : %s\n", locked ? "Locked" : "Free");
740 		snd_iprintf(buffer, "queued time events : %d\n", snd_seq_prioq_avail(q->timeq));
741 		snd_iprintf(buffer, "queued tick events : %d\n", snd_seq_prioq_avail(q->tickq));
742 		snd_iprintf(buffer, "timer state        : %s\n", tmr->running ? "Running" : "Stopped");
743 		snd_iprintf(buffer, "timer PPQ          : %d\n", tmr->ppq);
744 		snd_iprintf(buffer, "current tempo      : %d\n", tmr->tempo);
745 		snd_iprintf(buffer, "tempo base         : %d ns\n", tmr->tempo_base);
746 		snd_iprintf(buffer, "current BPM        : %d\n", bpm);
747 		snd_iprintf(buffer, "current time       : %d.%09d s\n", tmr->cur_time.tv_sec, tmr->cur_time.tv_nsec);
748 		snd_iprintf(buffer, "current tick       : %d\n", tmr->tick.cur_tick);
749 		snd_iprintf(buffer, "\n");
750 		queuefree(q);
751 	}
752 }
753 #endif /* CONFIG_SND_PROC_FS */
754 
755