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++) {
227 if (strncmp(q->name, name, sizeof(q->name)) == 0)
236 /* -------------------------------------------------------- */
238 void snd_seq_check_queue(struct snd_seq_queue *q, int atomic, int hop)
241 struct snd_seq_event_cell *cell;
242 snd_seq_tick_time_t cur_tick;
243 snd_seq_real_time_t cur_time;
248 /* make this function non-reentrant */
249 spin_lock_irqsave(&q->check_lock, flags);
250 if (q->check_blocked) {
252 spin_unlock_irqrestore(&q->check_lock, flags);
253 return; /* other thread is already checking queues */
255 q->check_blocked = 1;
256 spin_unlock_irqrestore(&q->check_lock, flags);
259 /* Process tick queue... */
260 cur_tick = snd_seq_timer_get_cur_tick(q->timer);
262 cell = snd_seq_prioq_cell_out(q->tickq, &cur_tick);
265 snd_seq_dispatch_event(cell, atomic, hop);
268 /* Process time queue... */
269 cur_time = snd_seq_timer_get_cur_time(q->timer, false);
271 cell = snd_seq_prioq_cell_out(q->timeq, &cur_time);
274 snd_seq_dispatch_event(cell, atomic, hop);
278 spin_lock_irqsave(&q->check_lock, flags);
279 if (q->check_again) {
281 spin_unlock_irqrestore(&q->check_lock, flags);
284 q->check_blocked = 0;
285 spin_unlock_irqrestore(&q->check_lock, flags);
289 /* enqueue a event to singe queue */
290 int snd_seq_enqueue_event(struct snd_seq_event_cell *cell, int atomic, int hop)
293 struct snd_seq_queue *q;
295 if (snd_BUG_ON(!cell))
297 dest = cell->event.queue; /* destination queue */
301 /* handle relative time stamps, convert them into absolute */
302 if ((cell->event.flags & SNDRV_SEQ_TIME_MODE_MASK) == SNDRV_SEQ_TIME_MODE_REL) {
303 switch (cell->event.flags & SNDRV_SEQ_TIME_STAMP_MASK) {
304 case SNDRV_SEQ_TIME_STAMP_TICK:
305 cell->event.time.tick += q->timer->tick.cur_tick;
308 case SNDRV_SEQ_TIME_STAMP_REAL:
309 snd_seq_inc_real_time(&cell->event.time.time,
310 &q->timer->cur_time);
313 cell->event.flags &= ~SNDRV_SEQ_TIME_MODE_MASK;
314 cell->event.flags |= SNDRV_SEQ_TIME_MODE_ABS;
316 /* enqueue event in the real-time or midi queue */
317 switch (cell->event.flags & SNDRV_SEQ_TIME_STAMP_MASK) {
318 case SNDRV_SEQ_TIME_STAMP_TICK:
319 err = snd_seq_prioq_cell_in(q->tickq, cell);
322 case SNDRV_SEQ_TIME_STAMP_REAL:
324 err = snd_seq_prioq_cell_in(q->timeq, cell);
329 queuefree(q); /* unlock */
333 /* trigger dispatching */
334 snd_seq_check_queue(q, atomic, hop);
336 queuefree(q); /* unlock */
342 /*----------------------------------------------------------------*/
344 static inline int check_access(struct snd_seq_queue *q, int client)
346 return (q->owner == client) || (!q->locked && !q->klocked);
349 /* check if the client has permission to modify queue parameters.
350 * if it does, lock the queue
352 static int queue_access_lock(struct snd_seq_queue *q, int client)
357 spin_lock_irqsave(&q->owner_lock, flags);
358 access_ok = check_access(q, client);
361 spin_unlock_irqrestore(&q->owner_lock, flags);
365 /* unlock the queue */
366 static inline void queue_access_unlock(struct snd_seq_queue *q)
370 spin_lock_irqsave(&q->owner_lock, flags);
372 spin_unlock_irqrestore(&q->owner_lock, flags);
375 /* exported - only checking permission */
376 int snd_seq_queue_check_access(int queueid, int client)
378 struct snd_seq_queue *q = queueptr(queueid);
384 spin_lock_irqsave(&q->owner_lock, flags);
385 access_ok = check_access(q, client);
386 spin_unlock_irqrestore(&q->owner_lock, flags);
391 /*----------------------------------------------------------------*/
394 * change queue's owner and permission
396 int snd_seq_queue_set_owner(int queueid, int client, int locked)
398 struct snd_seq_queue *q = queueptr(queueid);
404 if (! queue_access_lock(q, client)) {
409 spin_lock_irqsave(&q->owner_lock, flags);
410 q->locked = locked ? 1 : 0;
412 spin_unlock_irqrestore(&q->owner_lock, flags);
413 queue_access_unlock(q);
420 /*----------------------------------------------------------------*/
423 * q->use mutex should be down before calling this function to avoid
424 * confliction with snd_seq_queue_use()
426 int snd_seq_queue_timer_open(int queueid)
429 struct snd_seq_queue *queue;
430 struct snd_seq_timer *tmr;
432 queue = queueptr(queueid);
436 result = snd_seq_timer_open(queue);
438 snd_seq_timer_defaults(tmr);
439 result = snd_seq_timer_open(queue);
446 * q->use mutex should be down before calling this function
448 int snd_seq_queue_timer_close(int queueid)
450 struct snd_seq_queue *queue;
453 queue = queueptr(queueid);
456 snd_seq_timer_close(queue);
461 /* change queue tempo and ppq */
462 int snd_seq_queue_timer_set_tempo(int queueid, int client,
463 struct snd_seq_queue_tempo *info)
465 struct snd_seq_queue *q = queueptr(queueid);
470 if (! queue_access_lock(q, client)) {
475 result = snd_seq_timer_set_tempo_ppq(q->timer, info->tempo, info->ppq);
476 if (result >= 0 && info->skew_base > 0)
477 result = snd_seq_timer_set_skew(q->timer, info->skew_value,
479 queue_access_unlock(q);
484 /* use or unuse this queue */
485 static void queue_use(struct snd_seq_queue *queue, int client, int use)
488 if (!test_and_set_bit(client, queue->clients_bitmap))
491 if (test_and_clear_bit(client, queue->clients_bitmap))
494 if (queue->clients) {
495 if (use && queue->clients == 1)
496 snd_seq_timer_defaults(queue->timer);
497 snd_seq_timer_open(queue);
499 snd_seq_timer_close(queue);
503 /* use or unuse this queue -
504 * if it is the first client, starts the timer.
505 * if it is not longer used by any clients, stop the timer.
507 int snd_seq_queue_use(int queueid, int client, int use)
509 struct snd_seq_queue *queue;
511 queue = queueptr(queueid);
514 mutex_lock(&queue->timer_mutex);
515 queue_use(queue, client, use);
516 mutex_unlock(&queue->timer_mutex);
522 * check if queue is used by the client
523 * return negative value if the queue is invalid.
524 * return 0 if not used, 1 if used.
526 int snd_seq_queue_is_used(int queueid, int client)
528 struct snd_seq_queue *q;
531 q = queueptr(queueid);
533 return -EINVAL; /* invalid queue */
534 result = test_bit(client, q->clients_bitmap) ? 1 : 0;
540 /*----------------------------------------------------------------*/
542 /* final stage notification -
543 * remove cells for no longer exist client (for non-owned queue)
544 * or delete this queue (for owned queue)
546 void snd_seq_queue_client_leave(int client)
549 struct snd_seq_queue *q;
551 /* delete own queues from queue list */
552 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
553 q = queue_list_remove(i, client);
558 /* remove cells from existing queues -
559 * they are not owned by this client
561 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
565 if (test_bit(client, q->clients_bitmap)) {
566 snd_seq_prioq_leave(q->tickq, client, 0);
567 snd_seq_prioq_leave(q->timeq, client, 0);
568 snd_seq_queue_use(q->queue, client, 0);
576 /*----------------------------------------------------------------*/
578 /* remove cells from all queues */
579 void snd_seq_queue_client_leave_cells(int client)
582 struct snd_seq_queue *q;
584 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
588 snd_seq_prioq_leave(q->tickq, client, 0);
589 snd_seq_prioq_leave(q->timeq, client, 0);
594 /* remove cells based on flush criteria */
595 void snd_seq_queue_remove_cells(int client, struct snd_seq_remove_events *info)
598 struct snd_seq_queue *q;
600 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
604 if (test_bit(client, q->clients_bitmap) &&
605 (! (info->remove_mode & SNDRV_SEQ_REMOVE_DEST) ||
606 q->queue == info->queue)) {
607 snd_seq_prioq_remove_events(q->tickq, client, info);
608 snd_seq_prioq_remove_events(q->timeq, client, info);
614 /*----------------------------------------------------------------*/
617 * send events to all subscribed ports
619 static void queue_broadcast_event(struct snd_seq_queue *q, struct snd_seq_event *ev,
622 struct snd_seq_event sev;
626 sev.flags = SNDRV_SEQ_TIME_STAMP_TICK|SNDRV_SEQ_TIME_MODE_ABS;
627 sev.time.tick = q->timer->tick.cur_tick;
628 sev.queue = q->queue;
629 sev.data.queue.queue = q->queue;
631 /* broadcast events from Timer port */
632 sev.source.client = SNDRV_SEQ_CLIENT_SYSTEM;
633 sev.source.port = SNDRV_SEQ_PORT_SYSTEM_TIMER;
634 sev.dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS;
635 snd_seq_kernel_client_dispatch(SNDRV_SEQ_CLIENT_SYSTEM, &sev, atomic, hop);
639 * process a received queue-control event.
640 * this function is exported for seq_sync.c.
642 static void snd_seq_queue_process_event(struct snd_seq_queue *q,
643 struct snd_seq_event *ev,
647 case SNDRV_SEQ_EVENT_START:
648 snd_seq_prioq_leave(q->tickq, ev->source.client, 1);
649 snd_seq_prioq_leave(q->timeq, ev->source.client, 1);
650 if (! snd_seq_timer_start(q->timer))
651 queue_broadcast_event(q, ev, atomic, hop);
654 case SNDRV_SEQ_EVENT_CONTINUE:
655 if (! snd_seq_timer_continue(q->timer))
656 queue_broadcast_event(q, ev, atomic, hop);
659 case SNDRV_SEQ_EVENT_STOP:
660 snd_seq_timer_stop(q->timer);
661 queue_broadcast_event(q, ev, atomic, hop);
664 case SNDRV_SEQ_EVENT_TEMPO:
665 snd_seq_timer_set_tempo(q->timer, ev->data.queue.param.value);
666 queue_broadcast_event(q, ev, atomic, hop);
669 case SNDRV_SEQ_EVENT_SETPOS_TICK:
670 if (snd_seq_timer_set_position_tick(q->timer, ev->data.queue.param.time.tick) == 0) {
671 queue_broadcast_event(q, ev, atomic, hop);
675 case SNDRV_SEQ_EVENT_SETPOS_TIME:
676 if (snd_seq_timer_set_position_time(q->timer, ev->data.queue.param.time.time) == 0) {
677 queue_broadcast_event(q, ev, atomic, hop);
680 case SNDRV_SEQ_EVENT_QUEUE_SKEW:
681 if (snd_seq_timer_set_skew(q->timer,
682 ev->data.queue.param.skew.value,
683 ev->data.queue.param.skew.base) == 0) {
684 queue_broadcast_event(q, ev, atomic, hop);
692 * Queue control via timer control port:
693 * this function is exported as a callback of timer port.
695 int snd_seq_control_queue(struct snd_seq_event *ev, int atomic, int hop)
697 struct snd_seq_queue *q;
701 q = queueptr(ev->data.queue.queue);
706 if (! queue_access_lock(q, ev->source.client)) {
711 snd_seq_queue_process_event(q, ev, atomic, hop);
713 queue_access_unlock(q);
719 /*----------------------------------------------------------------*/
721 #ifdef CONFIG_SND_PROC_FS
722 /* exported to seq_info.c */
723 void snd_seq_info_queues_read(struct snd_info_entry *entry,
724 struct snd_info_buffer *buffer)
727 struct snd_seq_queue *q;
728 struct snd_seq_timer *tmr;
732 for (i = 0; i < SNDRV_SEQ_MAX_QUEUES; i++) {
739 bpm = 60000000 / tmr->tempo;
743 spin_lock_irq(&q->owner_lock);
746 spin_unlock_irq(&q->owner_lock);
748 snd_iprintf(buffer, "queue %d: [%s]\n", q->queue, q->name);
749 snd_iprintf(buffer, "owned by client : %d\n", owner);
750 snd_iprintf(buffer, "lock status : %s\n", locked ? "Locked" : "Free");
751 snd_iprintf(buffer, "queued time events : %d\n", snd_seq_prioq_avail(q->timeq));
752 snd_iprintf(buffer, "queued tick events : %d\n", snd_seq_prioq_avail(q->tickq));
753 snd_iprintf(buffer, "timer state : %s\n", tmr->running ? "Running" : "Stopped");
754 snd_iprintf(buffer, "timer PPQ : %d\n", tmr->ppq);
755 snd_iprintf(buffer, "current tempo : %d\n", tmr->tempo);
756 snd_iprintf(buffer, "current BPM : %d\n", bpm);
757 snd_iprintf(buffer, "current time : %d.%09d s\n", tmr->cur_time.tv_sec, tmr->cur_time.tv_nsec);
758 snd_iprintf(buffer, "current tick : %d\n", tmr->tick.cur_tick);
759 snd_iprintf(buffer, "\n");
763 #endif /* CONFIG_SND_PROC_FS */