1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * ALSA sequencer Timing queue handling
4 * Copyright (c) 1998-1999 by Frank van de Pol <fvdpol@coil.demon.nl>
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
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
22 * - Addition of experimental sync support.
25 #include <linux/init.h>
26 #include <linux/slab.h>
27 #include <sound/core.h>
29 #include "seq_memory.h"
30 #include "seq_queue.h"
31 #include "seq_clientmgr.h"
33 #include "seq_timer.h"
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;
42 int snd_seq_queue_get_cur_queues(void)
47 /*----------------------------------------------------------------*/
49 /* assign queue id and insert to list */
50 static int queue_list_add(struct snd_seq_queue *q)
55 spin_lock_irqsave(&queue_list_lock, flags);
56 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
57 if (! queue_list[i]) {
61 spin_unlock_irqrestore(&queue_list_lock, flags);
65 spin_unlock_irqrestore(&queue_list_lock, flags);
69 static struct snd_seq_queue *queue_list_remove(int id, int client)
71 struct snd_seq_queue *q;
74 spin_lock_irqsave(&queue_list_lock, flags);
77 spin_lock(&q->owner_lock);
78 if (q->owner == client) {
81 spin_unlock(&q->owner_lock);
82 queue_list[id] = NULL;
84 spin_unlock_irqrestore(&queue_list_lock, flags);
87 spin_unlock(&q->owner_lock);
89 spin_unlock_irqrestore(&queue_list_lock, flags);
93 /*----------------------------------------------------------------*/
95 /* create new queue (constructor) */
96 static struct snd_seq_queue *queue_new(int owner, int locked)
98 struct snd_seq_queue *q;
100 q = kzalloc(sizeof(*q), GFP_KERNEL);
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);
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);
128 /* delete queue (destructor) */
129 static void queue_delete(struct snd_seq_queue *q)
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);
147 /*----------------------------------------------------------------*/
149 /* delete all existing queues */
150 void snd_seq_queues_delete(void)
155 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
157 queue_delete(queue_list[i]);
161 static void queue_use(struct snd_seq_queue *queue, int client, int use);
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).
168 struct snd_seq_queue *snd_seq_queue_alloc(int client, int locked, unsigned int info_flags)
170 struct snd_seq_queue *q;
172 q = queue_new(client, locked);
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);
181 return ERR_PTR(-ENOMEM);
186 /* delete a queue - queue must be owned by the client */
187 int snd_seq_queue_delete(int client, int queueid)
189 struct snd_seq_queue *q;
191 if (queueid < 0 || queueid >= SNDRV_SEQ_MAX_QUEUES)
193 q = queue_list_remove(queueid, client);
202 /* return pointer to queue structure for specified id */
203 struct snd_seq_queue *queueptr(int queueid)
205 struct snd_seq_queue *q;
208 if (queueid < 0 || queueid >= SNDRV_SEQ_MAX_QUEUES)
210 spin_lock_irqsave(&queue_list_lock, flags);
211 q = queue_list[queueid];
213 snd_use_lock_use(&q->use_lock);
214 spin_unlock_irqrestore(&queue_list_lock, flags);
218 /* return the (first) queue matching with the specified name */
219 struct snd_seq_queue *snd_seq_queue_find_name(char *name)
222 struct snd_seq_queue *q;
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)
235 /* -------------------------------------------------------- */
237 void snd_seq_check_queue(struct snd_seq_queue *q, int atomic, int hop)
240 struct snd_seq_event_cell *cell;
241 snd_seq_tick_time_t cur_tick;
242 snd_seq_real_time_t cur_time;
247 /* make this function non-reentrant */
248 spin_lock_irqsave(&q->check_lock, flags);
249 if (q->check_blocked) {
251 spin_unlock_irqrestore(&q->check_lock, flags);
252 return; /* other thread is already checking queues */
254 q->check_blocked = 1;
255 spin_unlock_irqrestore(&q->check_lock, flags);
258 /* Process tick queue... */
259 cur_tick = snd_seq_timer_get_cur_tick(q->timer);
261 cell = snd_seq_prioq_cell_out(q->tickq, &cur_tick);
264 snd_seq_dispatch_event(cell, atomic, hop);
267 /* Process time queue... */
268 cur_time = snd_seq_timer_get_cur_time(q->timer, false);
270 cell = snd_seq_prioq_cell_out(q->timeq, &cur_time);
273 snd_seq_dispatch_event(cell, atomic, hop);
277 spin_lock_irqsave(&q->check_lock, flags);
278 if (q->check_again) {
280 spin_unlock_irqrestore(&q->check_lock, flags);
283 q->check_blocked = 0;
284 spin_unlock_irqrestore(&q->check_lock, flags);
288 /* enqueue a event to singe queue */
289 int snd_seq_enqueue_event(struct snd_seq_event_cell *cell, int atomic, int hop)
292 struct snd_seq_queue *q;
294 if (snd_BUG_ON(!cell))
296 dest = cell->event.queue; /* destination queue */
300 /* handle relative time stamps, convert them into absolute */
301 if ((cell->event.flags & SNDRV_SEQ_TIME_MODE_MASK) == SNDRV_SEQ_TIME_MODE_REL) {
302 switch (cell->event.flags & SNDRV_SEQ_TIME_STAMP_MASK) {
303 case SNDRV_SEQ_TIME_STAMP_TICK:
304 cell->event.time.tick += q->timer->tick.cur_tick;
307 case SNDRV_SEQ_TIME_STAMP_REAL:
308 snd_seq_inc_real_time(&cell->event.time.time,
309 &q->timer->cur_time);
312 cell->event.flags &= ~SNDRV_SEQ_TIME_MODE_MASK;
313 cell->event.flags |= SNDRV_SEQ_TIME_MODE_ABS;
315 /* enqueue event in the real-time or midi queue */
316 switch (cell->event.flags & SNDRV_SEQ_TIME_STAMP_MASK) {
317 case SNDRV_SEQ_TIME_STAMP_TICK:
318 err = snd_seq_prioq_cell_in(q->tickq, cell);
321 case SNDRV_SEQ_TIME_STAMP_REAL:
323 err = snd_seq_prioq_cell_in(q->timeq, cell);
328 queuefree(q); /* unlock */
332 /* trigger dispatching */
333 snd_seq_check_queue(q, atomic, hop);
335 queuefree(q); /* unlock */
341 /*----------------------------------------------------------------*/
343 static inline int check_access(struct snd_seq_queue *q, int client)
345 return (q->owner == client) || (!q->locked && !q->klocked);
348 /* check if the client has permission to modify queue parameters.
349 * if it does, lock the queue
351 static int queue_access_lock(struct snd_seq_queue *q, int client)
356 spin_lock_irqsave(&q->owner_lock, flags);
357 access_ok = check_access(q, client);
360 spin_unlock_irqrestore(&q->owner_lock, flags);
364 /* unlock the queue */
365 static inline void queue_access_unlock(struct snd_seq_queue *q)
369 spin_lock_irqsave(&q->owner_lock, flags);
371 spin_unlock_irqrestore(&q->owner_lock, flags);
374 /* exported - only checking permission */
375 int snd_seq_queue_check_access(int queueid, int client)
377 struct snd_seq_queue *q = queueptr(queueid);
383 spin_lock_irqsave(&q->owner_lock, flags);
384 access_ok = check_access(q, client);
385 spin_unlock_irqrestore(&q->owner_lock, flags);
390 /*----------------------------------------------------------------*/
393 * change queue's owner and permission
395 int snd_seq_queue_set_owner(int queueid, int client, int locked)
397 struct snd_seq_queue *q = queueptr(queueid);
403 if (! queue_access_lock(q, client)) {
408 spin_lock_irqsave(&q->owner_lock, flags);
409 q->locked = locked ? 1 : 0;
411 spin_unlock_irqrestore(&q->owner_lock, flags);
412 queue_access_unlock(q);
419 /*----------------------------------------------------------------*/
422 * q->use mutex should be down before calling this function to avoid
423 * confliction with snd_seq_queue_use()
425 int snd_seq_queue_timer_open(int queueid)
428 struct snd_seq_queue *queue;
429 struct snd_seq_timer *tmr;
431 queue = queueptr(queueid);
435 if ((result = snd_seq_timer_open(queue)) < 0) {
436 snd_seq_timer_defaults(tmr);
437 result = snd_seq_timer_open(queue);
444 * q->use mutex should be down before calling this function
446 int snd_seq_queue_timer_close(int queueid)
448 struct snd_seq_queue *queue;
451 queue = queueptr(queueid);
454 snd_seq_timer_close(queue);
459 /* change queue tempo and ppq */
460 int snd_seq_queue_timer_set_tempo(int queueid, int client,
461 struct snd_seq_queue_tempo *info)
463 struct snd_seq_queue *q = queueptr(queueid);
468 if (! queue_access_lock(q, client)) {
473 result = snd_seq_timer_set_tempo_ppq(q->timer, info->tempo, info->ppq);
474 if (result >= 0 && info->skew_base > 0)
475 result = snd_seq_timer_set_skew(q->timer, info->skew_value,
477 queue_access_unlock(q);
482 /* use or unuse this queue */
483 static void queue_use(struct snd_seq_queue *queue, int client, int use)
486 if (!test_and_set_bit(client, queue->clients_bitmap))
489 if (test_and_clear_bit(client, queue->clients_bitmap))
492 if (queue->clients) {
493 if (use && queue->clients == 1)
494 snd_seq_timer_defaults(queue->timer);
495 snd_seq_timer_open(queue);
497 snd_seq_timer_close(queue);
501 /* use or unuse this queue -
502 * if it is the first client, starts the timer.
503 * if it is not longer used by any clients, stop the timer.
505 int snd_seq_queue_use(int queueid, int client, int use)
507 struct snd_seq_queue *queue;
509 queue = queueptr(queueid);
512 mutex_lock(&queue->timer_mutex);
513 queue_use(queue, client, use);
514 mutex_unlock(&queue->timer_mutex);
520 * check if queue is used by the client
521 * return negative value if the queue is invalid.
522 * return 0 if not used, 1 if used.
524 int snd_seq_queue_is_used(int queueid, int client)
526 struct snd_seq_queue *q;
529 q = queueptr(queueid);
531 return -EINVAL; /* invalid queue */
532 result = test_bit(client, q->clients_bitmap) ? 1 : 0;
538 /*----------------------------------------------------------------*/
540 /* notification that client has left the system -
541 * stop the timer on all queues owned by this client
543 void snd_seq_queue_client_termination(int client)
547 struct snd_seq_queue *q;
550 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
551 if ((q = queueptr(i)) == NULL)
553 spin_lock_irqsave(&q->owner_lock, flags);
554 matched = (q->owner == client);
557 spin_unlock_irqrestore(&q->owner_lock, flags);
559 if (q->timer->running)
560 snd_seq_timer_stop(q->timer);
561 snd_seq_timer_reset(q->timer);
567 /* final stage notification -
568 * remove cells for no longer exist client (for non-owned queue)
569 * or delete this queue (for owned queue)
571 void snd_seq_queue_client_leave(int client)
574 struct snd_seq_queue *q;
576 /* delete own queues from queue list */
577 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
578 if ((q = queue_list_remove(i, client)) != NULL)
582 /* remove cells from existing queues -
583 * they are not owned by this client
585 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
586 if ((q = queueptr(i)) == NULL)
588 if (test_bit(client, q->clients_bitmap)) {
589 snd_seq_prioq_leave(q->tickq, client, 0);
590 snd_seq_prioq_leave(q->timeq, client, 0);
591 snd_seq_queue_use(q->queue, client, 0);
599 /*----------------------------------------------------------------*/
601 /* remove cells from all queues */
602 void snd_seq_queue_client_leave_cells(int client)
605 struct snd_seq_queue *q;
607 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
608 if ((q = queueptr(i)) == NULL)
610 snd_seq_prioq_leave(q->tickq, client, 0);
611 snd_seq_prioq_leave(q->timeq, client, 0);
616 /* remove cells based on flush criteria */
617 void snd_seq_queue_remove_cells(int client, struct snd_seq_remove_events *info)
620 struct snd_seq_queue *q;
622 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
623 if ((q = queueptr(i)) == NULL)
625 if (test_bit(client, q->clients_bitmap) &&
626 (! (info->remove_mode & SNDRV_SEQ_REMOVE_DEST) ||
627 q->queue == info->queue)) {
628 snd_seq_prioq_remove_events(q->tickq, client, info);
629 snd_seq_prioq_remove_events(q->timeq, client, info);
635 /*----------------------------------------------------------------*/
638 * send events to all subscribed ports
640 static void queue_broadcast_event(struct snd_seq_queue *q, struct snd_seq_event *ev,
643 struct snd_seq_event sev;
647 sev.flags = SNDRV_SEQ_TIME_STAMP_TICK|SNDRV_SEQ_TIME_MODE_ABS;
648 sev.time.tick = q->timer->tick.cur_tick;
649 sev.queue = q->queue;
650 sev.data.queue.queue = q->queue;
652 /* broadcast events from Timer port */
653 sev.source.client = SNDRV_SEQ_CLIENT_SYSTEM;
654 sev.source.port = SNDRV_SEQ_PORT_SYSTEM_TIMER;
655 sev.dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS;
656 snd_seq_kernel_client_dispatch(SNDRV_SEQ_CLIENT_SYSTEM, &sev, atomic, hop);
660 * process a received queue-control event.
661 * this function is exported for seq_sync.c.
663 static void snd_seq_queue_process_event(struct snd_seq_queue *q,
664 struct snd_seq_event *ev,
668 case SNDRV_SEQ_EVENT_START:
669 snd_seq_prioq_leave(q->tickq, ev->source.client, 1);
670 snd_seq_prioq_leave(q->timeq, ev->source.client, 1);
671 if (! snd_seq_timer_start(q->timer))
672 queue_broadcast_event(q, ev, atomic, hop);
675 case SNDRV_SEQ_EVENT_CONTINUE:
676 if (! snd_seq_timer_continue(q->timer))
677 queue_broadcast_event(q, ev, atomic, hop);
680 case SNDRV_SEQ_EVENT_STOP:
681 snd_seq_timer_stop(q->timer);
682 queue_broadcast_event(q, ev, atomic, hop);
685 case SNDRV_SEQ_EVENT_TEMPO:
686 snd_seq_timer_set_tempo(q->timer, ev->data.queue.param.value);
687 queue_broadcast_event(q, ev, atomic, hop);
690 case SNDRV_SEQ_EVENT_SETPOS_TICK:
691 if (snd_seq_timer_set_position_tick(q->timer, ev->data.queue.param.time.tick) == 0) {
692 queue_broadcast_event(q, ev, atomic, hop);
696 case SNDRV_SEQ_EVENT_SETPOS_TIME:
697 if (snd_seq_timer_set_position_time(q->timer, ev->data.queue.param.time.time) == 0) {
698 queue_broadcast_event(q, ev, atomic, hop);
701 case SNDRV_SEQ_EVENT_QUEUE_SKEW:
702 if (snd_seq_timer_set_skew(q->timer,
703 ev->data.queue.param.skew.value,
704 ev->data.queue.param.skew.base) == 0) {
705 queue_broadcast_event(q, ev, atomic, hop);
713 * Queue control via timer control port:
714 * this function is exported as a callback of timer port.
716 int snd_seq_control_queue(struct snd_seq_event *ev, int atomic, int hop)
718 struct snd_seq_queue *q;
722 q = queueptr(ev->data.queue.queue);
727 if (! queue_access_lock(q, ev->source.client)) {
732 snd_seq_queue_process_event(q, ev, atomic, hop);
734 queue_access_unlock(q);
740 /*----------------------------------------------------------------*/
742 #ifdef CONFIG_SND_PROC_FS
743 /* exported to seq_info.c */
744 void snd_seq_info_queues_read(struct snd_info_entry *entry,
745 struct snd_info_buffer *buffer)
748 struct snd_seq_queue *q;
749 struct snd_seq_timer *tmr;
753 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
754 if ((q = queueptr(i)) == NULL)
759 bpm = 60000000 / tmr->tempo;
763 spin_lock_irq(&q->owner_lock);
766 spin_unlock_irq(&q->owner_lock);
768 snd_iprintf(buffer, "queue %d: [%s]\n", q->queue, q->name);
769 snd_iprintf(buffer, "owned by client : %d\n", owner);
770 snd_iprintf(buffer, "lock status : %s\n", locked ? "Locked" : "Free");
771 snd_iprintf(buffer, "queued time events : %d\n", snd_seq_prioq_avail(q->timeq));
772 snd_iprintf(buffer, "queued tick events : %d\n", snd_seq_prioq_avail(q->tickq));
773 snd_iprintf(buffer, "timer state : %s\n", tmr->running ? "Running" : "Stopped");
774 snd_iprintf(buffer, "timer PPQ : %d\n", tmr->ppq);
775 snd_iprintf(buffer, "current tempo : %d\n", tmr->tempo);
776 snd_iprintf(buffer, "current BPM : %d\n", bpm);
777 snd_iprintf(buffer, "current time : %d.%09d s\n", tmr->cur_time.tv_sec, tmr->cur_time.tv_nsec);
778 snd_iprintf(buffer, "current tick : %d\n", tmr->tick.cur_tick);
779 snd_iprintf(buffer, "\n");
783 #endif /* CONFIG_SND_PROC_FS */