1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * ALSA sequencer Client Manager
9 #include <linux/init.h>
10 #include <linux/export.h>
11 #include <linux/slab.h>
12 #include <sound/core.h>
13 #include <sound/minors.h>
14 #include <linux/kmod.h>
16 #include <sound/seq_kernel.h>
17 #include "seq_clientmgr.h"
18 #include "seq_memory.h"
19 #include "seq_queue.h"
20 #include "seq_timer.h"
22 #include "seq_system.h"
23 #include <sound/seq_device.h>
25 #include <linux/compat.h>
30 * this module handles the connections of userland and kernel clients
35 * There are four ranges of client numbers (last two shared):
36 * 0..15: global clients
37 * 16..127: statically allocated client numbers for cards 0..27
38 * 128..191: dynamically allocated client numbers for cards 28..31
39 * 128..191: dynamically allocated client numbers for applications
42 /* number of kernel non-card clients */
43 #define SNDRV_SEQ_GLOBAL_CLIENTS 16
44 /* clients per cards, for static clients */
45 #define SNDRV_SEQ_CLIENTS_PER_CARD 4
46 /* dynamically allocated client numbers (both kernel drivers and user space) */
47 #define SNDRV_SEQ_DYNAMIC_CLIENTS_BEGIN 128
49 #define SNDRV_SEQ_LFLG_INPUT 0x0001
50 #define SNDRV_SEQ_LFLG_OUTPUT 0x0002
51 #define SNDRV_SEQ_LFLG_OPEN (SNDRV_SEQ_LFLG_INPUT|SNDRV_SEQ_LFLG_OUTPUT)
53 static DEFINE_SPINLOCK(clients_lock);
54 static DEFINE_MUTEX(register_mutex);
59 static char clienttablock[SNDRV_SEQ_MAX_CLIENTS];
60 static struct snd_seq_client *clienttab[SNDRV_SEQ_MAX_CLIENTS];
61 static struct snd_seq_usage client_usage;
66 static int bounce_error_event(struct snd_seq_client *client,
67 struct snd_seq_event *event,
68 int err, int atomic, int hop);
69 static int snd_seq_deliver_single_event(struct snd_seq_client *client,
70 struct snd_seq_event *event,
71 int filter, int atomic, int hop);
75 static inline unsigned short snd_seq_file_flags(struct file *file)
77 switch (file->f_mode & (FMODE_READ | FMODE_WRITE)) {
79 return SNDRV_SEQ_LFLG_OUTPUT;
81 return SNDRV_SEQ_LFLG_INPUT;
83 return SNDRV_SEQ_LFLG_OPEN;
87 static inline int snd_seq_write_pool_allocated(struct snd_seq_client *client)
89 return snd_seq_total_cells(client->pool) > 0;
92 /* return pointer to client structure for specified id */
93 static struct snd_seq_client *clientptr(int clientid)
95 if (clientid < 0 || clientid >= SNDRV_SEQ_MAX_CLIENTS) {
96 pr_debug("ALSA: seq: oops. Trying to get pointer to client %d\n",
100 return clienttab[clientid];
103 struct snd_seq_client *snd_seq_client_use_ptr(int clientid)
106 struct snd_seq_client *client;
108 if (clientid < 0 || clientid >= SNDRV_SEQ_MAX_CLIENTS) {
109 pr_debug("ALSA: seq: oops. Trying to get pointer to client %d\n",
113 spin_lock_irqsave(&clients_lock, flags);
114 client = clientptr(clientid);
117 if (clienttablock[clientid]) {
118 spin_unlock_irqrestore(&clients_lock, flags);
121 spin_unlock_irqrestore(&clients_lock, flags);
122 #ifdef CONFIG_MODULES
123 if (!in_interrupt()) {
124 static DECLARE_BITMAP(client_requested, SNDRV_SEQ_GLOBAL_CLIENTS);
125 static DECLARE_BITMAP(card_requested, SNDRV_CARDS);
127 if (clientid < SNDRV_SEQ_GLOBAL_CLIENTS) {
130 if (!test_and_set_bit(clientid, client_requested)) {
131 for (idx = 0; idx < 15; idx++) {
132 if (seq_client_load[idx] < 0)
134 if (seq_client_load[idx] == clientid) {
135 request_module("snd-seq-client-%i",
141 } else if (clientid < SNDRV_SEQ_DYNAMIC_CLIENTS_BEGIN) {
142 int card = (clientid - SNDRV_SEQ_GLOBAL_CLIENTS) /
143 SNDRV_SEQ_CLIENTS_PER_CARD;
144 if (card < snd_ecards_limit) {
145 if (!test_and_set_bit(card, card_requested))
146 snd_request_card(card);
147 snd_seq_device_load_drivers();
150 spin_lock_irqsave(&clients_lock, flags);
151 client = clientptr(clientid);
154 spin_unlock_irqrestore(&clients_lock, flags);
160 snd_use_lock_use(&client->use_lock);
161 spin_unlock_irqrestore(&clients_lock, flags);
165 /* Take refcount and perform ioctl_mutex lock on the given client;
166 * used only for OSS sequencer
167 * Unlock via snd_seq_client_ioctl_unlock() below
169 bool snd_seq_client_ioctl_lock(int clientid)
171 struct snd_seq_client *client;
173 client = snd_seq_client_use_ptr(clientid);
176 mutex_lock(&client->ioctl_mutex);
177 /* The client isn't unrefed here; see snd_seq_client_ioctl_unlock() */
180 EXPORT_SYMBOL_GPL(snd_seq_client_ioctl_lock);
182 /* Unlock and unref the given client; for OSS sequencer use only */
183 void snd_seq_client_ioctl_unlock(int clientid)
185 struct snd_seq_client *client;
187 client = snd_seq_client_use_ptr(clientid);
188 if (WARN_ON(!client))
190 mutex_unlock(&client->ioctl_mutex);
191 /* The doubly unrefs below are intentional; the first one releases the
192 * leftover from snd_seq_client_ioctl_lock() above, and the second one
193 * is for releasing snd_seq_client_use_ptr() in this function
195 snd_seq_client_unlock(client);
196 snd_seq_client_unlock(client);
198 EXPORT_SYMBOL_GPL(snd_seq_client_ioctl_unlock);
200 static void usage_alloc(struct snd_seq_usage *res, int num)
203 if (res->cur > res->peak)
204 res->peak = res->cur;
207 static void usage_free(struct snd_seq_usage *res, int num)
212 /* initialise data structures */
213 int __init client_init_data(void)
215 /* zap out the client table */
216 memset(&clienttablock, 0, sizeof(clienttablock));
217 memset(&clienttab, 0, sizeof(clienttab));
222 static struct snd_seq_client *seq_create_client1(int client_index, int poolsize)
225 struct snd_seq_client *client;
227 /* init client data */
228 client = kzalloc(sizeof(*client), GFP_KERNEL);
231 client->pool = snd_seq_pool_new(poolsize);
232 if (client->pool == NULL) {
236 client->type = NO_CLIENT;
237 snd_use_lock_init(&client->use_lock);
238 rwlock_init(&client->ports_lock);
239 mutex_init(&client->ports_mutex);
240 INIT_LIST_HEAD(&client->ports_list_head);
241 mutex_init(&client->ioctl_mutex);
243 /* find free slot in the client table */
244 spin_lock_irq(&clients_lock);
245 if (client_index < 0) {
246 for (c = SNDRV_SEQ_DYNAMIC_CLIENTS_BEGIN;
247 c < SNDRV_SEQ_MAX_CLIENTS;
249 if (clienttab[c] || clienttablock[c])
251 clienttab[client->number = c] = client;
252 spin_unlock_irq(&clients_lock);
256 if (clienttab[client_index] == NULL && !clienttablock[client_index]) {
257 clienttab[client->number = client_index] = client;
258 spin_unlock_irq(&clients_lock);
262 spin_unlock_irq(&clients_lock);
263 snd_seq_pool_delete(&client->pool);
265 return NULL; /* no free slot found or busy, return failure code */
269 static int seq_free_client1(struct snd_seq_client *client)
273 spin_lock_irq(&clients_lock);
274 clienttablock[client->number] = 1;
275 clienttab[client->number] = NULL;
276 spin_unlock_irq(&clients_lock);
277 snd_seq_delete_all_ports(client);
278 snd_seq_queue_client_leave(client->number);
279 snd_use_lock_sync(&client->use_lock);
281 snd_seq_pool_delete(&client->pool);
282 spin_lock_irq(&clients_lock);
283 clienttablock[client->number] = 0;
284 spin_unlock_irq(&clients_lock);
289 static void seq_free_client(struct snd_seq_client * client)
291 mutex_lock(®ister_mutex);
292 switch (client->type) {
294 pr_warn("ALSA: seq: Trying to free unused client %d\n",
299 seq_free_client1(client);
300 usage_free(&client_usage, 1);
304 pr_err("ALSA: seq: Trying to free client %d with undefined type = %d\n",
305 client->number, client->type);
307 mutex_unlock(®ister_mutex);
309 snd_seq_system_client_ev_client_exit(client->number);
314 /* -------------------------------------------------------- */
316 /* create a user client */
317 static int snd_seq_open(struct inode *inode, struct file *file)
319 int c, mode; /* client id */
320 struct snd_seq_client *client;
321 struct snd_seq_user_client *user;
324 err = stream_open(inode, file);
328 mutex_lock(®ister_mutex);
329 client = seq_create_client1(-1, SNDRV_SEQ_DEFAULT_EVENTS);
331 mutex_unlock(®ister_mutex);
332 return -ENOMEM; /* failure code */
335 mode = snd_seq_file_flags(file);
336 if (mode & SNDRV_SEQ_LFLG_INPUT)
337 client->accept_input = 1;
338 if (mode & SNDRV_SEQ_LFLG_OUTPUT)
339 client->accept_output = 1;
341 user = &client->data.user;
343 user->fifo_pool_size = 0;
345 if (mode & SNDRV_SEQ_LFLG_INPUT) {
346 user->fifo_pool_size = SNDRV_SEQ_DEFAULT_CLIENT_EVENTS;
347 user->fifo = snd_seq_fifo_new(user->fifo_pool_size);
348 if (user->fifo == NULL) {
349 seq_free_client1(client);
351 mutex_unlock(®ister_mutex);
356 usage_alloc(&client_usage, 1);
357 client->type = USER_CLIENT;
358 mutex_unlock(®ister_mutex);
361 file->private_data = client;
363 /* fill client data */
365 sprintf(client->name, "Client-%d", c);
366 client->data.user.owner = get_pid(task_pid(current));
368 /* make others aware this new client */
369 snd_seq_system_client_ev_client_start(c);
374 /* delete a user client */
375 static int snd_seq_release(struct inode *inode, struct file *file)
377 struct snd_seq_client *client = file->private_data;
380 seq_free_client(client);
381 if (client->data.user.fifo)
382 snd_seq_fifo_delete(&client->data.user.fifo);
383 put_pid(client->data.user.owner);
391 /* handle client read() */
392 /* possible error values:
393 * -ENXIO invalid client or file open mode
394 * -ENOSPC FIFO overflow (the flag is cleared after this error report)
395 * -EINVAL no enough user-space buffer to write the whole event
396 * -EFAULT seg. fault during copy to user space
398 static ssize_t snd_seq_read(struct file *file, char __user *buf, size_t count,
401 struct snd_seq_client *client = file->private_data;
402 struct snd_seq_fifo *fifo;
405 struct snd_seq_event_cell *cell;
407 if (!(snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_INPUT))
410 if (!access_ok(buf, count))
413 /* check client structures are in place */
414 if (snd_BUG_ON(!client))
417 if (!client->accept_input)
419 fifo = client->data.user.fifo;
423 if (atomic_read(&fifo->overflow) > 0) {
424 /* buffer overflow is detected */
425 snd_seq_fifo_clear(fifo);
426 /* return error code */
432 snd_seq_fifo_lock(fifo);
434 /* while data available in queue */
435 while (count >= sizeof(struct snd_seq_event)) {
438 nonblock = (file->f_flags & O_NONBLOCK) || result > 0;
439 err = snd_seq_fifo_cell_out(fifo, &cell, nonblock);
442 if (snd_seq_ev_is_variable(&cell->event)) {
443 struct snd_seq_event tmpev;
445 tmpev.data.ext.len &= ~SNDRV_SEQ_EXT_MASK;
446 if (copy_to_user(buf, &tmpev, sizeof(struct snd_seq_event))) {
450 count -= sizeof(struct snd_seq_event);
451 buf += sizeof(struct snd_seq_event);
452 err = snd_seq_expand_var_event(&cell->event, count,
453 (char __force *)buf, 0,
454 sizeof(struct snd_seq_event));
461 if (copy_to_user(buf, &cell->event, sizeof(struct snd_seq_event))) {
465 count -= sizeof(struct snd_seq_event);
466 buf += sizeof(struct snd_seq_event);
468 snd_seq_cell_free(cell);
469 cell = NULL; /* to be sure */
470 result += sizeof(struct snd_seq_event);
475 snd_seq_fifo_cell_putback(fifo, cell);
476 if (err == -EAGAIN && result > 0)
479 snd_seq_fifo_unlock(fifo);
481 return (err < 0) ? err : result;
486 * check access permission to the port
488 static int check_port_perm(struct snd_seq_client_port *port, unsigned int flags)
490 if ((port->capability & flags) != flags)
496 * check if the destination client is available, and return the pointer
497 * if filter is non-zero, client filter bitmap is tested.
499 static struct snd_seq_client *get_event_dest_client(struct snd_seq_event *event,
502 struct snd_seq_client *dest;
504 dest = snd_seq_client_use_ptr(event->dest.client);
507 if (! dest->accept_input)
509 if ((dest->filter & SNDRV_SEQ_FILTER_USE_EVENT) &&
510 ! test_bit(event->type, dest->event_filter))
512 if (filter && !(dest->filter & filter))
515 return dest; /* ok - accessible */
517 snd_seq_client_unlock(dest);
523 * Return the error event.
525 * If the receiver client is a user client, the original event is
526 * encapsulated in SNDRV_SEQ_EVENT_BOUNCE as variable length event. If
527 * the original event is also variable length, the external data is
528 * copied after the event record.
529 * If the receiver client is a kernel client, the original event is
530 * quoted in SNDRV_SEQ_EVENT_KERNEL_ERROR, since this requires no extra
533 static int bounce_error_event(struct snd_seq_client *client,
534 struct snd_seq_event *event,
535 int err, int atomic, int hop)
537 struct snd_seq_event bounce_ev;
540 if (client == NULL ||
541 ! (client->filter & SNDRV_SEQ_FILTER_BOUNCE) ||
542 ! client->accept_input)
543 return 0; /* ignored */
545 /* set up quoted error */
546 memset(&bounce_ev, 0, sizeof(bounce_ev));
547 bounce_ev.type = SNDRV_SEQ_EVENT_KERNEL_ERROR;
548 bounce_ev.flags = SNDRV_SEQ_EVENT_LENGTH_FIXED;
549 bounce_ev.queue = SNDRV_SEQ_QUEUE_DIRECT;
550 bounce_ev.source.client = SNDRV_SEQ_CLIENT_SYSTEM;
551 bounce_ev.source.port = SNDRV_SEQ_PORT_SYSTEM_ANNOUNCE;
552 bounce_ev.dest.client = client->number;
553 bounce_ev.dest.port = event->source.port;
554 bounce_ev.data.quote.origin = event->dest;
555 bounce_ev.data.quote.event = event;
556 bounce_ev.data.quote.value = -err; /* use positive value */
557 result = snd_seq_deliver_single_event(NULL, &bounce_ev, 0, atomic, hop + 1);
559 client->event_lost++;
568 * rewrite the time-stamp of the event record with the curren time
569 * of the given queue.
570 * return non-zero if updated.
572 static int update_timestamp_of_queue(struct snd_seq_event *event,
573 int queue, int real_time)
575 struct snd_seq_queue *q;
580 event->queue = queue;
581 event->flags &= ~SNDRV_SEQ_TIME_STAMP_MASK;
583 event->time.time = snd_seq_timer_get_cur_time(q->timer, true);
584 event->flags |= SNDRV_SEQ_TIME_STAMP_REAL;
586 event->time.tick = snd_seq_timer_get_cur_tick(q->timer);
587 event->flags |= SNDRV_SEQ_TIME_STAMP_TICK;
595 * deliver an event to the specified destination.
596 * if filter is non-zero, client filter bitmap is tested.
598 * RETURN VALUE: 0 : if succeeded
601 static int snd_seq_deliver_single_event(struct snd_seq_client *client,
602 struct snd_seq_event *event,
603 int filter, int atomic, int hop)
605 struct snd_seq_client *dest = NULL;
606 struct snd_seq_client_port *dest_port = NULL;
607 int result = -ENOENT;
610 direct = snd_seq_ev_is_direct(event);
612 dest = get_event_dest_client(event, filter);
615 dest_port = snd_seq_port_use_ptr(dest, event->dest.port);
616 if (dest_port == NULL)
619 /* check permission */
620 if (! check_port_perm(dest_port, SNDRV_SEQ_PORT_CAP_WRITE)) {
625 if (dest_port->timestamping)
626 update_timestamp_of_queue(event, dest_port->time_queue,
627 dest_port->time_real);
629 switch (dest->type) {
631 if (dest->data.user.fifo)
632 result = snd_seq_fifo_event_in(dest->data.user.fifo, event);
636 if (dest_port->event_input == NULL)
638 result = dest_port->event_input(event, direct,
639 dest_port->private_data,
648 snd_seq_port_unlock(dest_port);
650 snd_seq_client_unlock(dest);
652 if (result < 0 && !direct) {
653 result = bounce_error_event(client, event, result, atomic, hop);
660 * send the event to all subscribers:
662 static int deliver_to_subscribers(struct snd_seq_client *client,
663 struct snd_seq_event *event,
666 struct snd_seq_subscribers *subs;
667 int err, result = 0, num_ev = 0;
668 struct snd_seq_event event_saved;
669 struct snd_seq_client_port *src_port;
670 struct snd_seq_port_subs_info *grp;
672 src_port = snd_seq_port_use_ptr(client, event->source.port);
673 if (src_port == NULL)
674 return -EINVAL; /* invalid source port */
675 /* save original event record */
676 event_saved = *event;
677 grp = &src_port->c_src;
681 read_lock(&grp->list_lock);
683 down_read_nested(&grp->list_mutex, hop);
684 list_for_each_entry(subs, &grp->list_head, src_list) {
685 /* both ports ready? */
686 if (atomic_read(&subs->ref_count) != 2)
688 event->dest = subs->info.dest;
689 if (subs->info.flags & SNDRV_SEQ_PORT_SUBS_TIMESTAMP)
690 /* convert time according to flag with subscription */
691 update_timestamp_of_queue(event, subs->info.queue,
692 subs->info.flags & SNDRV_SEQ_PORT_SUBS_TIME_REAL);
693 err = snd_seq_deliver_single_event(client, event,
696 /* save first error that occurs and continue */
702 /* restore original event record */
703 *event = event_saved;
706 read_unlock(&grp->list_lock);
708 up_read(&grp->list_mutex);
709 *event = event_saved; /* restore */
710 snd_seq_port_unlock(src_port);
711 return (result < 0) ? result : num_ev;
715 #ifdef SUPPORT_BROADCAST
717 * broadcast to all ports:
719 static int port_broadcast_event(struct snd_seq_client *client,
720 struct snd_seq_event *event,
723 int num_ev = 0, err, result = 0;
724 struct snd_seq_client *dest_client;
725 struct snd_seq_client_port *port;
727 dest_client = get_event_dest_client(event, SNDRV_SEQ_FILTER_BROADCAST);
728 if (dest_client == NULL)
729 return 0; /* no matching destination */
731 read_lock(&dest_client->ports_lock);
732 list_for_each_entry(port, &dest_client->ports_list_head, list) {
733 event->dest.port = port->addr.port;
734 /* pass NULL as source client to avoid error bounce */
735 err = snd_seq_deliver_single_event(NULL, event,
736 SNDRV_SEQ_FILTER_BROADCAST,
739 /* save first error that occurs and continue */
746 read_unlock(&dest_client->ports_lock);
747 snd_seq_client_unlock(dest_client);
748 event->dest.port = SNDRV_SEQ_ADDRESS_BROADCAST; /* restore */
749 return (result < 0) ? result : num_ev;
753 * send the event to all clients:
754 * if destination port is also ADDRESS_BROADCAST, deliver to all ports.
756 static int broadcast_event(struct snd_seq_client *client,
757 struct snd_seq_event *event, int atomic, int hop)
759 int err, result = 0, num_ev = 0;
761 struct snd_seq_addr addr;
763 addr = event->dest; /* save */
765 for (dest = 0; dest < SNDRV_SEQ_MAX_CLIENTS; dest++) {
766 /* don't send to itself */
767 if (dest == client->number)
769 event->dest.client = dest;
770 event->dest.port = addr.port;
771 if (addr.port == SNDRV_SEQ_ADDRESS_BROADCAST)
772 err = port_broadcast_event(client, event, atomic, hop);
774 /* pass NULL as source client to avoid error bounce */
775 err = snd_seq_deliver_single_event(NULL, event,
776 SNDRV_SEQ_FILTER_BROADCAST,
779 /* save first error that occurs and continue */
786 event->dest = addr; /* restore */
787 return (result < 0) ? result : num_ev;
791 /* multicast - not supported yet */
792 static int multicast_event(struct snd_seq_client *client, struct snd_seq_event *event,
795 pr_debug("ALSA: seq: multicast not supported yet.\n");
796 return 0; /* ignored */
798 #endif /* SUPPORT_BROADCAST */
801 /* deliver an event to the destination port(s).
802 * if the event is to subscribers or broadcast, the event is dispatched
803 * to multiple targets.
805 * RETURN VALUE: n > 0 : the number of delivered events.
806 * n == 0 : the event was not passed to any client.
807 * n < 0 : error - event was not processed.
809 static int snd_seq_deliver_event(struct snd_seq_client *client, struct snd_seq_event *event,
815 if (hop >= SNDRV_SEQ_MAX_HOPS) {
816 pr_debug("ALSA: seq: too long delivery path (%d:%d->%d:%d)\n",
817 event->source.client, event->source.port,
818 event->dest.client, event->dest.port);
822 if (snd_seq_ev_is_variable(event) &&
823 snd_BUG_ON(atomic && (event->data.ext.len & SNDRV_SEQ_EXT_USRPTR)))
826 if (event->queue == SNDRV_SEQ_ADDRESS_SUBSCRIBERS ||
827 event->dest.client == SNDRV_SEQ_ADDRESS_SUBSCRIBERS)
828 result = deliver_to_subscribers(client, event, atomic, hop);
829 #ifdef SUPPORT_BROADCAST
830 else if (event->queue == SNDRV_SEQ_ADDRESS_BROADCAST ||
831 event->dest.client == SNDRV_SEQ_ADDRESS_BROADCAST)
832 result = broadcast_event(client, event, atomic, hop);
833 else if (event->dest.client >= SNDRV_SEQ_MAX_CLIENTS)
834 result = multicast_event(client, event, atomic, hop);
835 else if (event->dest.port == SNDRV_SEQ_ADDRESS_BROADCAST)
836 result = port_broadcast_event(client, event, atomic, hop);
839 result = snd_seq_deliver_single_event(client, event, 0, atomic, hop);
845 * dispatch an event cell:
846 * This function is called only from queue check routines in timer
847 * interrupts or after enqueued.
848 * The event cell shall be released or re-queued in this function.
850 * RETURN VALUE: n > 0 : the number of delivered events.
851 * n == 0 : the event was not passed to any client.
852 * n < 0 : error - event was not processed.
854 int snd_seq_dispatch_event(struct snd_seq_event_cell *cell, int atomic, int hop)
856 struct snd_seq_client *client;
859 if (snd_BUG_ON(!cell))
862 client = snd_seq_client_use_ptr(cell->event.source.client);
863 if (client == NULL) {
864 snd_seq_cell_free(cell); /* release this cell */
868 if (cell->event.type == SNDRV_SEQ_EVENT_NOTE) {
870 * the event cell is re-used as a NOTE-OFF event and
873 struct snd_seq_event tmpev, *ev;
875 /* reserve this event to enqueue note-off later */
877 tmpev.type = SNDRV_SEQ_EVENT_NOTEON;
878 result = snd_seq_deliver_event(client, &tmpev, atomic, hop);
881 * This was originally a note event. We now re-use the
882 * cell for the note-off event.
886 ev->type = SNDRV_SEQ_EVENT_NOTEOFF;
887 ev->flags |= SNDRV_SEQ_PRIORITY_HIGH;
889 /* add the duration time */
890 switch (ev->flags & SNDRV_SEQ_TIME_STAMP_MASK) {
891 case SNDRV_SEQ_TIME_STAMP_TICK:
892 ev->time.tick += ev->data.note.duration;
894 case SNDRV_SEQ_TIME_STAMP_REAL:
895 /* unit for duration is ms */
896 ev->time.time.tv_nsec += 1000000 * (ev->data.note.duration % 1000);
897 ev->time.time.tv_sec += ev->data.note.duration / 1000 +
898 ev->time.time.tv_nsec / 1000000000;
899 ev->time.time.tv_nsec %= 1000000000;
902 ev->data.note.velocity = ev->data.note.off_velocity;
904 /* Now queue this cell as the note off event */
905 if (snd_seq_enqueue_event(cell, atomic, hop) < 0)
906 snd_seq_cell_free(cell); /* release this cell */
910 * event cell is freed after processing the event
913 result = snd_seq_deliver_event(client, &cell->event, atomic, hop);
914 snd_seq_cell_free(cell);
917 snd_seq_client_unlock(client);
922 /* Allocate a cell from client pool and enqueue it to queue:
923 * if pool is empty and blocking is TRUE, sleep until a new cell is
926 static int snd_seq_client_enqueue_event(struct snd_seq_client *client,
927 struct snd_seq_event *event,
928 struct file *file, int blocking,
930 struct mutex *mutexp)
932 struct snd_seq_event_cell *cell;
935 /* special queue values - force direct passing */
936 if (event->queue == SNDRV_SEQ_ADDRESS_SUBSCRIBERS) {
937 event->dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS;
938 event->queue = SNDRV_SEQ_QUEUE_DIRECT;
940 #ifdef SUPPORT_BROADCAST
941 if (event->queue == SNDRV_SEQ_ADDRESS_BROADCAST) {
942 event->dest.client = SNDRV_SEQ_ADDRESS_BROADCAST;
943 event->queue = SNDRV_SEQ_QUEUE_DIRECT;
946 if (event->dest.client == SNDRV_SEQ_ADDRESS_SUBSCRIBERS) {
947 /* check presence of source port */
948 struct snd_seq_client_port *src_port = snd_seq_port_use_ptr(client, event->source.port);
949 if (src_port == NULL)
951 snd_seq_port_unlock(src_port);
954 /* direct event processing without enqueued */
955 if (snd_seq_ev_is_direct(event)) {
956 if (event->type == SNDRV_SEQ_EVENT_NOTE)
957 return -EINVAL; /* this event must be enqueued! */
958 return snd_seq_deliver_event(client, event, atomic, hop);
961 /* Not direct, normal queuing */
962 if (snd_seq_queue_is_used(event->queue, client->number) <= 0)
963 return -EINVAL; /* invalid queue */
964 if (! snd_seq_write_pool_allocated(client))
965 return -ENXIO; /* queue is not allocated */
967 /* allocate an event cell */
968 err = snd_seq_event_dup(client->pool, event, &cell, !blocking || atomic,
973 /* we got a cell. enqueue it. */
974 err = snd_seq_enqueue_event(cell, atomic, hop);
976 snd_seq_cell_free(cell);
985 * check validity of event type and data length.
986 * return non-zero if invalid.
988 static int check_event_type_and_length(struct snd_seq_event *ev)
990 switch (snd_seq_ev_length_type(ev)) {
991 case SNDRV_SEQ_EVENT_LENGTH_FIXED:
992 if (snd_seq_ev_is_variable_type(ev))
995 case SNDRV_SEQ_EVENT_LENGTH_VARIABLE:
996 if (! snd_seq_ev_is_variable_type(ev) ||
997 (ev->data.ext.len & ~SNDRV_SEQ_EXT_MASK) >= SNDRV_SEQ_MAX_EVENT_LEN)
1000 case SNDRV_SEQ_EVENT_LENGTH_VARUSR:
1001 if (! snd_seq_ev_is_direct(ev))
1009 /* handle write() */
1010 /* possible error values:
1011 * -ENXIO invalid client or file open mode
1012 * -ENOMEM malloc failed
1013 * -EFAULT seg. fault during copy from user space
1014 * -EINVAL invalid event
1015 * -EAGAIN no space in output pool
1016 * -EINTR interrupts while sleep
1017 * -EMLINK too many hops
1018 * others depends on return value from driver callback
1020 static ssize_t snd_seq_write(struct file *file, const char __user *buf,
1021 size_t count, loff_t *offset)
1023 struct snd_seq_client *client = file->private_data;
1024 int written = 0, len;
1026 struct snd_seq_event event;
1028 if (!(snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_OUTPUT))
1031 /* check client structures are in place */
1032 if (snd_BUG_ON(!client))
1035 if (!client->accept_output || client->pool == NULL)
1040 /* allocate the pool now if the pool is not allocated yet */
1041 mutex_lock(&client->ioctl_mutex);
1042 if (client->pool->size > 0 && !snd_seq_write_pool_allocated(client)) {
1043 err = snd_seq_pool_init(client->pool);
1048 /* only process whole events */
1050 while (count >= sizeof(struct snd_seq_event)) {
1051 /* Read in the event header from the user */
1052 len = sizeof(event);
1053 if (copy_from_user(&event, buf, len)) {
1057 event.source.client = client->number; /* fill in client number */
1058 /* Check for extension data length */
1059 if (check_event_type_and_length(&event)) {
1064 /* check for special events */
1065 if (event.type == SNDRV_SEQ_EVENT_NONE)
1067 else if (snd_seq_ev_is_reserved(&event)) {
1072 if (snd_seq_ev_is_variable(&event)) {
1073 int extlen = event.data.ext.len & ~SNDRV_SEQ_EXT_MASK;
1074 if ((size_t)(extlen + len) > count) {
1075 /* back out, will get an error this time or next */
1079 /* set user space pointer */
1080 event.data.ext.len = extlen | SNDRV_SEQ_EXT_USRPTR;
1081 event.data.ext.ptr = (char __force *)buf
1082 + sizeof(struct snd_seq_event);
1083 len += extlen; /* increment data length */
1085 #ifdef CONFIG_COMPAT
1086 if (client->convert32 && snd_seq_ev_is_varusr(&event)) {
1087 void *ptr = (void __force *)compat_ptr(event.data.raw32.d[1]);
1088 event.data.ext.ptr = ptr;
1093 /* ok, enqueue it */
1094 err = snd_seq_client_enqueue_event(client, &event, file,
1095 !(file->f_flags & O_NONBLOCK),
1096 0, 0, &client->ioctl_mutex);
1102 /* Update pointers and counts */
1107 /* let's have a coffee break if too many events are queued */
1108 if (++handled >= 200) {
1109 mutex_unlock(&client->ioctl_mutex);
1115 mutex_unlock(&client->ioctl_mutex);
1116 return written ? written : err;
1123 static __poll_t snd_seq_poll(struct file *file, poll_table * wait)
1125 struct snd_seq_client *client = file->private_data;
1128 /* check client structures are in place */
1129 if (snd_BUG_ON(!client))
1132 if ((snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_INPUT) &&
1133 client->data.user.fifo) {
1135 /* check if data is available in the outqueue */
1136 if (snd_seq_fifo_poll_wait(client->data.user.fifo, file, wait))
1137 mask |= EPOLLIN | EPOLLRDNORM;
1140 if (snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_OUTPUT) {
1142 /* check if data is available in the pool */
1143 if (!snd_seq_write_pool_allocated(client) ||
1144 snd_seq_pool_poll_wait(client->pool, file, wait))
1145 mask |= EPOLLOUT | EPOLLWRNORM;
1152 /*-----------------------------------------------------*/
1154 static int snd_seq_ioctl_pversion(struct snd_seq_client *client, void *arg)
1156 int *pversion = arg;
1158 *pversion = SNDRV_SEQ_VERSION;
1162 static int snd_seq_ioctl_client_id(struct snd_seq_client *client, void *arg)
1164 int *client_id = arg;
1166 *client_id = client->number;
1170 /* SYSTEM_INFO ioctl() */
1171 static int snd_seq_ioctl_system_info(struct snd_seq_client *client, void *arg)
1173 struct snd_seq_system_info *info = arg;
1175 memset(info, 0, sizeof(*info));
1176 /* fill the info fields */
1177 info->queues = SNDRV_SEQ_MAX_QUEUES;
1178 info->clients = SNDRV_SEQ_MAX_CLIENTS;
1179 info->ports = SNDRV_SEQ_MAX_PORTS;
1180 info->channels = 256; /* fixed limit */
1181 info->cur_clients = client_usage.cur;
1182 info->cur_queues = snd_seq_queue_get_cur_queues();
1188 /* RUNNING_MODE ioctl() */
1189 static int snd_seq_ioctl_running_mode(struct snd_seq_client *client, void *arg)
1191 struct snd_seq_running_info *info = arg;
1192 struct snd_seq_client *cptr;
1195 /* requested client number */
1196 cptr = snd_seq_client_use_ptr(info->client);
1198 return -ENOENT; /* don't change !!! */
1200 #ifdef SNDRV_BIG_ENDIAN
1201 if (!info->big_endian) {
1206 if (info->big_endian) {
1212 if (info->cpu_mode > sizeof(long)) {
1216 cptr->convert32 = (info->cpu_mode < sizeof(long));
1218 snd_seq_client_unlock(cptr);
1222 /* CLIENT_INFO ioctl() */
1223 static void get_client_info(struct snd_seq_client *cptr,
1224 struct snd_seq_client_info *info)
1226 info->client = cptr->number;
1228 /* fill the info fields */
1229 info->type = cptr->type;
1230 strcpy(info->name, cptr->name);
1231 info->filter = cptr->filter;
1232 info->event_lost = cptr->event_lost;
1233 memcpy(info->event_filter, cptr->event_filter, 32);
1234 info->num_ports = cptr->num_ports;
1236 if (cptr->type == USER_CLIENT)
1237 info->pid = pid_vnr(cptr->data.user.owner);
1241 if (cptr->type == KERNEL_CLIENT)
1242 info->card = cptr->data.kernel.card ? cptr->data.kernel.card->number : -1;
1246 memset(info->reserved, 0, sizeof(info->reserved));
1249 static int snd_seq_ioctl_get_client_info(struct snd_seq_client *client,
1252 struct snd_seq_client_info *client_info = arg;
1253 struct snd_seq_client *cptr;
1255 /* requested client number */
1256 cptr = snd_seq_client_use_ptr(client_info->client);
1258 return -ENOENT; /* don't change !!! */
1260 get_client_info(cptr, client_info);
1261 snd_seq_client_unlock(cptr);
1267 /* CLIENT_INFO ioctl() */
1268 static int snd_seq_ioctl_set_client_info(struct snd_seq_client *client,
1271 struct snd_seq_client_info *client_info = arg;
1273 /* it is not allowed to set the info fields for an another client */
1274 if (client->number != client_info->client)
1276 /* also client type must be set now */
1277 if (client->type != client_info->type)
1280 /* fill the info fields */
1281 if (client_info->name[0])
1282 strscpy(client->name, client_info->name, sizeof(client->name));
1284 client->filter = client_info->filter;
1285 client->event_lost = client_info->event_lost;
1286 memcpy(client->event_filter, client_info->event_filter, 32);
1293 * CREATE PORT ioctl()
1295 static int snd_seq_ioctl_create_port(struct snd_seq_client *client, void *arg)
1297 struct snd_seq_port_info *info = arg;
1298 struct snd_seq_client_port *port;
1299 struct snd_seq_port_callback *callback;
1302 /* it is not allowed to create the port for an another client */
1303 if (info->addr.client != client->number)
1306 port = snd_seq_create_port(client, (info->flags & SNDRV_SEQ_PORT_FLG_GIVEN_PORT) ? info->addr.port : -1);
1310 if (client->type == USER_CLIENT && info->kernel) {
1311 port_idx = port->addr.port;
1312 snd_seq_port_unlock(port);
1313 snd_seq_delete_port(client, port_idx);
1316 if (client->type == KERNEL_CLIENT) {
1317 callback = info->kernel;
1319 if (callback->owner)
1320 port->owner = callback->owner;
1321 port->private_data = callback->private_data;
1322 port->private_free = callback->private_free;
1323 port->event_input = callback->event_input;
1324 port->c_src.open = callback->subscribe;
1325 port->c_src.close = callback->unsubscribe;
1326 port->c_dest.open = callback->use;
1327 port->c_dest.close = callback->unuse;
1331 info->addr = port->addr;
1333 snd_seq_set_port_info(port, info);
1334 snd_seq_system_client_ev_port_start(port->addr.client, port->addr.port);
1335 snd_seq_port_unlock(port);
1341 * DELETE PORT ioctl()
1343 static int snd_seq_ioctl_delete_port(struct snd_seq_client *client, void *arg)
1345 struct snd_seq_port_info *info = arg;
1348 /* it is not allowed to remove the port for an another client */
1349 if (info->addr.client != client->number)
1352 err = snd_seq_delete_port(client, info->addr.port);
1354 snd_seq_system_client_ev_port_exit(client->number, info->addr.port);
1360 * GET_PORT_INFO ioctl() (on any client)
1362 static int snd_seq_ioctl_get_port_info(struct snd_seq_client *client, void *arg)
1364 struct snd_seq_port_info *info = arg;
1365 struct snd_seq_client *cptr;
1366 struct snd_seq_client_port *port;
1368 cptr = snd_seq_client_use_ptr(info->addr.client);
1372 port = snd_seq_port_use_ptr(cptr, info->addr.port);
1374 snd_seq_client_unlock(cptr);
1375 return -ENOENT; /* don't change */
1379 snd_seq_get_port_info(port, info);
1380 snd_seq_port_unlock(port);
1381 snd_seq_client_unlock(cptr);
1388 * SET_PORT_INFO ioctl() (only ports on this/own client)
1390 static int snd_seq_ioctl_set_port_info(struct snd_seq_client *client, void *arg)
1392 struct snd_seq_port_info *info = arg;
1393 struct snd_seq_client_port *port;
1395 if (info->addr.client != client->number) /* only set our own ports ! */
1397 port = snd_seq_port_use_ptr(client, info->addr.port);
1399 snd_seq_set_port_info(port, info);
1400 snd_seq_port_unlock(port);
1407 * port subscription (connection)
1409 #define PERM_RD (SNDRV_SEQ_PORT_CAP_READ|SNDRV_SEQ_PORT_CAP_SUBS_READ)
1410 #define PERM_WR (SNDRV_SEQ_PORT_CAP_WRITE|SNDRV_SEQ_PORT_CAP_SUBS_WRITE)
1412 static int check_subscription_permission(struct snd_seq_client *client,
1413 struct snd_seq_client_port *sport,
1414 struct snd_seq_client_port *dport,
1415 struct snd_seq_port_subscribe *subs)
1417 if (client->number != subs->sender.client &&
1418 client->number != subs->dest.client) {
1419 /* connection by third client - check export permission */
1420 if (check_port_perm(sport, SNDRV_SEQ_PORT_CAP_NO_EXPORT))
1422 if (check_port_perm(dport, SNDRV_SEQ_PORT_CAP_NO_EXPORT))
1426 /* check read permission */
1427 /* if sender or receiver is the subscribing client itself,
1428 * no permission check is necessary
1430 if (client->number != subs->sender.client) {
1431 if (! check_port_perm(sport, PERM_RD))
1434 /* check write permission */
1435 if (client->number != subs->dest.client) {
1436 if (! check_port_perm(dport, PERM_WR))
1443 * send an subscription notify event to user client:
1444 * client must be user client.
1446 int snd_seq_client_notify_subscription(int client, int port,
1447 struct snd_seq_port_subscribe *info,
1450 struct snd_seq_event event;
1452 memset(&event, 0, sizeof(event));
1453 event.type = evtype;
1454 event.data.connect.dest = info->dest;
1455 event.data.connect.sender = info->sender;
1457 return snd_seq_system_notify(client, port, &event); /* non-atomic */
1462 * add to port's subscription list IOCTL interface
1464 static int snd_seq_ioctl_subscribe_port(struct snd_seq_client *client,
1467 struct snd_seq_port_subscribe *subs = arg;
1468 int result = -EINVAL;
1469 struct snd_seq_client *receiver = NULL, *sender = NULL;
1470 struct snd_seq_client_port *sport = NULL, *dport = NULL;
1472 receiver = snd_seq_client_use_ptr(subs->dest.client);
1475 sender = snd_seq_client_use_ptr(subs->sender.client);
1478 sport = snd_seq_port_use_ptr(sender, subs->sender.port);
1481 dport = snd_seq_port_use_ptr(receiver, subs->dest.port);
1485 result = check_subscription_permission(client, sport, dport, subs);
1490 result = snd_seq_port_connect(client, sender, sport, receiver, dport, subs);
1491 if (! result) /* broadcast announce */
1492 snd_seq_client_notify_subscription(SNDRV_SEQ_ADDRESS_SUBSCRIBERS, 0,
1493 subs, SNDRV_SEQ_EVENT_PORT_SUBSCRIBED);
1496 snd_seq_port_unlock(sport);
1498 snd_seq_port_unlock(dport);
1500 snd_seq_client_unlock(sender);
1502 snd_seq_client_unlock(receiver);
1508 * remove from port's subscription list
1510 static int snd_seq_ioctl_unsubscribe_port(struct snd_seq_client *client,
1513 struct snd_seq_port_subscribe *subs = arg;
1514 int result = -ENXIO;
1515 struct snd_seq_client *receiver = NULL, *sender = NULL;
1516 struct snd_seq_client_port *sport = NULL, *dport = NULL;
1518 receiver = snd_seq_client_use_ptr(subs->dest.client);
1521 sender = snd_seq_client_use_ptr(subs->sender.client);
1524 sport = snd_seq_port_use_ptr(sender, subs->sender.port);
1527 dport = snd_seq_port_use_ptr(receiver, subs->dest.port);
1531 result = check_subscription_permission(client, sport, dport, subs);
1535 result = snd_seq_port_disconnect(client, sender, sport, receiver, dport, subs);
1536 if (! result) /* broadcast announce */
1537 snd_seq_client_notify_subscription(SNDRV_SEQ_ADDRESS_SUBSCRIBERS, 0,
1538 subs, SNDRV_SEQ_EVENT_PORT_UNSUBSCRIBED);
1541 snd_seq_port_unlock(sport);
1543 snd_seq_port_unlock(dport);
1545 snd_seq_client_unlock(sender);
1547 snd_seq_client_unlock(receiver);
1552 /* CREATE_QUEUE ioctl() */
1553 static int snd_seq_ioctl_create_queue(struct snd_seq_client *client, void *arg)
1555 struct snd_seq_queue_info *info = arg;
1556 struct snd_seq_queue *q;
1558 q = snd_seq_queue_alloc(client->number, info->locked, info->flags);
1562 info->queue = q->queue;
1563 info->locked = q->locked;
1564 info->owner = q->owner;
1566 /* set queue name */
1568 snprintf(info->name, sizeof(info->name), "Queue-%d", q->queue);
1569 strscpy(q->name, info->name, sizeof(q->name));
1570 snd_use_lock_free(&q->use_lock);
1575 /* DELETE_QUEUE ioctl() */
1576 static int snd_seq_ioctl_delete_queue(struct snd_seq_client *client, void *arg)
1578 struct snd_seq_queue_info *info = arg;
1580 return snd_seq_queue_delete(client->number, info->queue);
1583 /* GET_QUEUE_INFO ioctl() */
1584 static int snd_seq_ioctl_get_queue_info(struct snd_seq_client *client,
1587 struct snd_seq_queue_info *info = arg;
1588 struct snd_seq_queue *q;
1590 q = queueptr(info->queue);
1594 memset(info, 0, sizeof(*info));
1595 info->queue = q->queue;
1596 info->owner = q->owner;
1597 info->locked = q->locked;
1598 strscpy(info->name, q->name, sizeof(info->name));
1604 /* SET_QUEUE_INFO ioctl() */
1605 static int snd_seq_ioctl_set_queue_info(struct snd_seq_client *client,
1608 struct snd_seq_queue_info *info = arg;
1609 struct snd_seq_queue *q;
1611 if (info->owner != client->number)
1614 /* change owner/locked permission */
1615 if (snd_seq_queue_check_access(info->queue, client->number)) {
1616 if (snd_seq_queue_set_owner(info->queue, client->number, info->locked) < 0)
1619 snd_seq_queue_use(info->queue, client->number, 1);
1624 q = queueptr(info->queue);
1627 if (q->owner != client->number) {
1631 strscpy(q->name, info->name, sizeof(q->name));
1637 /* GET_NAMED_QUEUE ioctl() */
1638 static int snd_seq_ioctl_get_named_queue(struct snd_seq_client *client,
1641 struct snd_seq_queue_info *info = arg;
1642 struct snd_seq_queue *q;
1644 q = snd_seq_queue_find_name(info->name);
1647 info->queue = q->queue;
1648 info->owner = q->owner;
1649 info->locked = q->locked;
1655 /* GET_QUEUE_STATUS ioctl() */
1656 static int snd_seq_ioctl_get_queue_status(struct snd_seq_client *client,
1659 struct snd_seq_queue_status *status = arg;
1660 struct snd_seq_queue *queue;
1661 struct snd_seq_timer *tmr;
1663 queue = queueptr(status->queue);
1666 memset(status, 0, sizeof(*status));
1667 status->queue = queue->queue;
1670 status->events = queue->tickq->cells + queue->timeq->cells;
1672 status->time = snd_seq_timer_get_cur_time(tmr, true);
1673 status->tick = snd_seq_timer_get_cur_tick(tmr);
1675 status->running = tmr->running;
1677 status->flags = queue->flags;
1684 /* GET_QUEUE_TEMPO ioctl() */
1685 static int snd_seq_ioctl_get_queue_tempo(struct snd_seq_client *client,
1688 struct snd_seq_queue_tempo *tempo = arg;
1689 struct snd_seq_queue *queue;
1690 struct snd_seq_timer *tmr;
1692 queue = queueptr(tempo->queue);
1695 memset(tempo, 0, sizeof(*tempo));
1696 tempo->queue = queue->queue;
1700 tempo->tempo = tmr->tempo;
1701 tempo->ppq = tmr->ppq;
1702 tempo->skew_value = tmr->skew;
1703 tempo->skew_base = tmr->skew_base;
1710 /* SET_QUEUE_TEMPO ioctl() */
1711 int snd_seq_set_queue_tempo(int client, struct snd_seq_queue_tempo *tempo)
1713 if (!snd_seq_queue_check_access(tempo->queue, client))
1715 return snd_seq_queue_timer_set_tempo(tempo->queue, client, tempo);
1717 EXPORT_SYMBOL(snd_seq_set_queue_tempo);
1719 static int snd_seq_ioctl_set_queue_tempo(struct snd_seq_client *client,
1722 struct snd_seq_queue_tempo *tempo = arg;
1725 result = snd_seq_set_queue_tempo(client->number, tempo);
1726 return result < 0 ? result : 0;
1730 /* GET_QUEUE_TIMER ioctl() */
1731 static int snd_seq_ioctl_get_queue_timer(struct snd_seq_client *client,
1734 struct snd_seq_queue_timer *timer = arg;
1735 struct snd_seq_queue *queue;
1736 struct snd_seq_timer *tmr;
1738 queue = queueptr(timer->queue);
1742 mutex_lock(&queue->timer_mutex);
1744 memset(timer, 0, sizeof(*timer));
1745 timer->queue = queue->queue;
1747 timer->type = tmr->type;
1748 if (tmr->type == SNDRV_SEQ_TIMER_ALSA) {
1749 timer->u.alsa.id = tmr->alsa_id;
1750 timer->u.alsa.resolution = tmr->preferred_resolution;
1752 mutex_unlock(&queue->timer_mutex);
1759 /* SET_QUEUE_TIMER ioctl() */
1760 static int snd_seq_ioctl_set_queue_timer(struct snd_seq_client *client,
1763 struct snd_seq_queue_timer *timer = arg;
1766 if (timer->type != SNDRV_SEQ_TIMER_ALSA)
1769 if (snd_seq_queue_check_access(timer->queue, client->number)) {
1770 struct snd_seq_queue *q;
1771 struct snd_seq_timer *tmr;
1773 q = queueptr(timer->queue);
1776 mutex_lock(&q->timer_mutex);
1778 snd_seq_queue_timer_close(timer->queue);
1779 tmr->type = timer->type;
1780 if (tmr->type == SNDRV_SEQ_TIMER_ALSA) {
1781 tmr->alsa_id = timer->u.alsa.id;
1782 tmr->preferred_resolution = timer->u.alsa.resolution;
1784 result = snd_seq_queue_timer_open(timer->queue);
1785 mutex_unlock(&q->timer_mutex);
1795 /* GET_QUEUE_CLIENT ioctl() */
1796 static int snd_seq_ioctl_get_queue_client(struct snd_seq_client *client,
1799 struct snd_seq_queue_client *info = arg;
1802 used = snd_seq_queue_is_used(info->queue, client->number);
1806 info->client = client->number;
1812 /* SET_QUEUE_CLIENT ioctl() */
1813 static int snd_seq_ioctl_set_queue_client(struct snd_seq_client *client,
1816 struct snd_seq_queue_client *info = arg;
1819 if (info->used >= 0) {
1820 err = snd_seq_queue_use(info->queue, client->number, info->used);
1825 return snd_seq_ioctl_get_queue_client(client, arg);
1829 /* GET_CLIENT_POOL ioctl() */
1830 static int snd_seq_ioctl_get_client_pool(struct snd_seq_client *client,
1833 struct snd_seq_client_pool *info = arg;
1834 struct snd_seq_client *cptr;
1836 cptr = snd_seq_client_use_ptr(info->client);
1839 memset(info, 0, sizeof(*info));
1840 info->client = cptr->number;
1841 info->output_pool = cptr->pool->size;
1842 info->output_room = cptr->pool->room;
1843 info->output_free = info->output_pool;
1844 info->output_free = snd_seq_unused_cells(cptr->pool);
1845 if (cptr->type == USER_CLIENT) {
1846 info->input_pool = cptr->data.user.fifo_pool_size;
1847 info->input_free = info->input_pool;
1848 info->input_free = snd_seq_fifo_unused_cells(cptr->data.user.fifo);
1850 info->input_pool = 0;
1851 info->input_free = 0;
1853 snd_seq_client_unlock(cptr);
1858 /* SET_CLIENT_POOL ioctl() */
1859 static int snd_seq_ioctl_set_client_pool(struct snd_seq_client *client,
1862 struct snd_seq_client_pool *info = arg;
1865 if (client->number != info->client)
1866 return -EINVAL; /* can't change other clients */
1868 if (info->output_pool >= 1 && info->output_pool <= SNDRV_SEQ_MAX_EVENTS &&
1869 (! snd_seq_write_pool_allocated(client) ||
1870 info->output_pool != client->pool->size)) {
1871 if (snd_seq_write_pool_allocated(client)) {
1872 /* is the pool in use? */
1873 if (atomic_read(&client->pool->counter))
1875 /* remove all existing cells */
1876 snd_seq_pool_mark_closing(client->pool);
1877 snd_seq_pool_done(client->pool);
1879 client->pool->size = info->output_pool;
1880 rc = snd_seq_pool_init(client->pool);
1884 if (client->type == USER_CLIENT && client->data.user.fifo != NULL &&
1885 info->input_pool >= 1 &&
1886 info->input_pool <= SNDRV_SEQ_MAX_CLIENT_EVENTS &&
1887 info->input_pool != client->data.user.fifo_pool_size) {
1888 /* change pool size */
1889 rc = snd_seq_fifo_resize(client->data.user.fifo, info->input_pool);
1892 client->data.user.fifo_pool_size = info->input_pool;
1894 if (info->output_room >= 1 &&
1895 info->output_room <= client->pool->size) {
1896 client->pool->room = info->output_room;
1899 return snd_seq_ioctl_get_client_pool(client, arg);
1903 /* REMOVE_EVENTS ioctl() */
1904 static int snd_seq_ioctl_remove_events(struct snd_seq_client *client,
1907 struct snd_seq_remove_events *info = arg;
1910 * Input mostly not implemented XXX.
1912 if (info->remove_mode & SNDRV_SEQ_REMOVE_INPUT) {
1914 * No restrictions so for a user client we can clear
1917 if (client->type == USER_CLIENT && client->data.user.fifo)
1918 snd_seq_fifo_clear(client->data.user.fifo);
1921 if (info->remove_mode & SNDRV_SEQ_REMOVE_OUTPUT)
1922 snd_seq_queue_remove_cells(client->number, info);
1929 * get subscription info
1931 static int snd_seq_ioctl_get_subscription(struct snd_seq_client *client,
1934 struct snd_seq_port_subscribe *subs = arg;
1936 struct snd_seq_client *sender = NULL;
1937 struct snd_seq_client_port *sport = NULL;
1940 sender = snd_seq_client_use_ptr(subs->sender.client);
1943 sport = snd_seq_port_use_ptr(sender, subs->sender.port);
1946 result = snd_seq_port_get_subscription(&sport->c_src, &subs->dest,
1950 snd_seq_port_unlock(sport);
1952 snd_seq_client_unlock(sender);
1959 * get subscription info - check only its presence
1961 static int snd_seq_ioctl_query_subs(struct snd_seq_client *client, void *arg)
1963 struct snd_seq_query_subs *subs = arg;
1964 int result = -ENXIO;
1965 struct snd_seq_client *cptr = NULL;
1966 struct snd_seq_client_port *port = NULL;
1967 struct snd_seq_port_subs_info *group;
1968 struct list_head *p;
1971 cptr = snd_seq_client_use_ptr(subs->root.client);
1974 port = snd_seq_port_use_ptr(cptr, subs->root.port);
1978 switch (subs->type) {
1979 case SNDRV_SEQ_QUERY_SUBS_READ:
1980 group = &port->c_src;
1982 case SNDRV_SEQ_QUERY_SUBS_WRITE:
1983 group = &port->c_dest;
1989 down_read(&group->list_mutex);
1990 /* search for the subscriber */
1991 subs->num_subs = group->count;
1994 list_for_each(p, &group->list_head) {
1995 if (i++ == subs->index) {
1997 struct snd_seq_subscribers *s;
1998 if (subs->type == SNDRV_SEQ_QUERY_SUBS_READ) {
1999 s = list_entry(p, struct snd_seq_subscribers, src_list);
2000 subs->addr = s->info.dest;
2002 s = list_entry(p, struct snd_seq_subscribers, dest_list);
2003 subs->addr = s->info.sender;
2005 subs->flags = s->info.flags;
2006 subs->queue = s->info.queue;
2011 up_read(&group->list_mutex);
2015 snd_seq_port_unlock(port);
2017 snd_seq_client_unlock(cptr);
2026 static int snd_seq_ioctl_query_next_client(struct snd_seq_client *client,
2029 struct snd_seq_client_info *info = arg;
2030 struct snd_seq_client *cptr = NULL;
2032 /* search for next client */
2033 if (info->client < INT_MAX)
2035 if (info->client < 0)
2037 for (; info->client < SNDRV_SEQ_MAX_CLIENTS; info->client++) {
2038 cptr = snd_seq_client_use_ptr(info->client);
2045 get_client_info(cptr, info);
2046 snd_seq_client_unlock(cptr);
2054 static int snd_seq_ioctl_query_next_port(struct snd_seq_client *client,
2057 struct snd_seq_port_info *info = arg;
2058 struct snd_seq_client *cptr;
2059 struct snd_seq_client_port *port = NULL;
2061 cptr = snd_seq_client_use_ptr(info->addr.client);
2065 /* search for next port */
2067 port = snd_seq_port_query_nearest(cptr, info);
2069 snd_seq_client_unlock(cptr);
2074 info->addr = port->addr;
2075 snd_seq_get_port_info(port, info);
2076 snd_seq_port_unlock(port);
2077 snd_seq_client_unlock(cptr);
2082 /* -------------------------------------------------------- */
2084 static const struct ioctl_handler {
2086 int (*func)(struct snd_seq_client *client, void *arg);
2087 } ioctl_handlers[] = {
2088 { SNDRV_SEQ_IOCTL_PVERSION, snd_seq_ioctl_pversion },
2089 { SNDRV_SEQ_IOCTL_CLIENT_ID, snd_seq_ioctl_client_id },
2090 { SNDRV_SEQ_IOCTL_SYSTEM_INFO, snd_seq_ioctl_system_info },
2091 { SNDRV_SEQ_IOCTL_RUNNING_MODE, snd_seq_ioctl_running_mode },
2092 { SNDRV_SEQ_IOCTL_GET_CLIENT_INFO, snd_seq_ioctl_get_client_info },
2093 { SNDRV_SEQ_IOCTL_SET_CLIENT_INFO, snd_seq_ioctl_set_client_info },
2094 { SNDRV_SEQ_IOCTL_CREATE_PORT, snd_seq_ioctl_create_port },
2095 { SNDRV_SEQ_IOCTL_DELETE_PORT, snd_seq_ioctl_delete_port },
2096 { SNDRV_SEQ_IOCTL_GET_PORT_INFO, snd_seq_ioctl_get_port_info },
2097 { SNDRV_SEQ_IOCTL_SET_PORT_INFO, snd_seq_ioctl_set_port_info },
2098 { SNDRV_SEQ_IOCTL_SUBSCRIBE_PORT, snd_seq_ioctl_subscribe_port },
2099 { SNDRV_SEQ_IOCTL_UNSUBSCRIBE_PORT, snd_seq_ioctl_unsubscribe_port },
2100 { SNDRV_SEQ_IOCTL_CREATE_QUEUE, snd_seq_ioctl_create_queue },
2101 { SNDRV_SEQ_IOCTL_DELETE_QUEUE, snd_seq_ioctl_delete_queue },
2102 { SNDRV_SEQ_IOCTL_GET_QUEUE_INFO, snd_seq_ioctl_get_queue_info },
2103 { SNDRV_SEQ_IOCTL_SET_QUEUE_INFO, snd_seq_ioctl_set_queue_info },
2104 { SNDRV_SEQ_IOCTL_GET_NAMED_QUEUE, snd_seq_ioctl_get_named_queue },
2105 { SNDRV_SEQ_IOCTL_GET_QUEUE_STATUS, snd_seq_ioctl_get_queue_status },
2106 { SNDRV_SEQ_IOCTL_GET_QUEUE_TEMPO, snd_seq_ioctl_get_queue_tempo },
2107 { SNDRV_SEQ_IOCTL_SET_QUEUE_TEMPO, snd_seq_ioctl_set_queue_tempo },
2108 { SNDRV_SEQ_IOCTL_GET_QUEUE_TIMER, snd_seq_ioctl_get_queue_timer },
2109 { SNDRV_SEQ_IOCTL_SET_QUEUE_TIMER, snd_seq_ioctl_set_queue_timer },
2110 { SNDRV_SEQ_IOCTL_GET_QUEUE_CLIENT, snd_seq_ioctl_get_queue_client },
2111 { SNDRV_SEQ_IOCTL_SET_QUEUE_CLIENT, snd_seq_ioctl_set_queue_client },
2112 { SNDRV_SEQ_IOCTL_GET_CLIENT_POOL, snd_seq_ioctl_get_client_pool },
2113 { SNDRV_SEQ_IOCTL_SET_CLIENT_POOL, snd_seq_ioctl_set_client_pool },
2114 { SNDRV_SEQ_IOCTL_GET_SUBSCRIPTION, snd_seq_ioctl_get_subscription },
2115 { SNDRV_SEQ_IOCTL_QUERY_NEXT_CLIENT, snd_seq_ioctl_query_next_client },
2116 { SNDRV_SEQ_IOCTL_QUERY_NEXT_PORT, snd_seq_ioctl_query_next_port },
2117 { SNDRV_SEQ_IOCTL_REMOVE_EVENTS, snd_seq_ioctl_remove_events },
2118 { SNDRV_SEQ_IOCTL_QUERY_SUBS, snd_seq_ioctl_query_subs },
2122 static long snd_seq_ioctl(struct file *file, unsigned int cmd,
2125 struct snd_seq_client *client = file->private_data;
2126 /* To use kernel stack for ioctl data. */
2130 struct snd_seq_system_info system_info;
2131 struct snd_seq_running_info running_info;
2132 struct snd_seq_client_info client_info;
2133 struct snd_seq_port_info port_info;
2134 struct snd_seq_port_subscribe port_subscribe;
2135 struct snd_seq_queue_info queue_info;
2136 struct snd_seq_queue_status queue_status;
2137 struct snd_seq_queue_tempo tempo;
2138 struct snd_seq_queue_timer queue_timer;
2139 struct snd_seq_queue_client queue_client;
2140 struct snd_seq_client_pool client_pool;
2141 struct snd_seq_remove_events remove_events;
2142 struct snd_seq_query_subs query_subs;
2144 const struct ioctl_handler *handler;
2148 if (snd_BUG_ON(!client))
2151 for (handler = ioctl_handlers; handler->cmd > 0; ++handler) {
2152 if (handler->cmd == cmd)
2155 if (handler->cmd == 0)
2158 memset(&buf, 0, sizeof(buf));
2161 * All of ioctl commands for ALSA sequencer get an argument of size
2162 * within 13 bits. We can safely pick up the size from the command.
2164 size = _IOC_SIZE(handler->cmd);
2165 if (handler->cmd & IOC_IN) {
2166 if (copy_from_user(&buf, (const void __user *)arg, size))
2170 mutex_lock(&client->ioctl_mutex);
2171 err = handler->func(client, &buf);
2172 mutex_unlock(&client->ioctl_mutex);
2174 /* Some commands includes a bug in 'dir' field. */
2175 if (handler->cmd == SNDRV_SEQ_IOCTL_SET_QUEUE_CLIENT ||
2176 handler->cmd == SNDRV_SEQ_IOCTL_SET_CLIENT_POOL ||
2177 (handler->cmd & IOC_OUT))
2178 if (copy_to_user((void __user *)arg, &buf, size))
2185 #ifdef CONFIG_COMPAT
2186 #include "seq_compat.c"
2188 #define snd_seq_ioctl_compat NULL
2191 /* -------------------------------------------------------- */
2194 /* exported to kernel modules */
2195 int snd_seq_create_kernel_client(struct snd_card *card, int client_index,
2196 const char *name_fmt, ...)
2198 struct snd_seq_client *client;
2201 if (snd_BUG_ON(in_interrupt()))
2204 if (card && client_index >= SNDRV_SEQ_CLIENTS_PER_CARD)
2206 if (card == NULL && client_index >= SNDRV_SEQ_GLOBAL_CLIENTS)
2209 mutex_lock(®ister_mutex);
2212 client_index += SNDRV_SEQ_GLOBAL_CLIENTS
2213 + card->number * SNDRV_SEQ_CLIENTS_PER_CARD;
2214 if (client_index >= SNDRV_SEQ_DYNAMIC_CLIENTS_BEGIN)
2218 /* empty write queue as default */
2219 client = seq_create_client1(client_index, 0);
2220 if (client == NULL) {
2221 mutex_unlock(®ister_mutex);
2222 return -EBUSY; /* failure code */
2224 usage_alloc(&client_usage, 1);
2226 client->accept_input = 1;
2227 client->accept_output = 1;
2228 client->data.kernel.card = card;
2230 va_start(args, name_fmt);
2231 vsnprintf(client->name, sizeof(client->name), name_fmt, args);
2234 client->type = KERNEL_CLIENT;
2235 mutex_unlock(®ister_mutex);
2237 /* make others aware this new client */
2238 snd_seq_system_client_ev_client_start(client->number);
2240 /* return client number to caller */
2241 return client->number;
2243 EXPORT_SYMBOL(snd_seq_create_kernel_client);
2245 /* exported to kernel modules */
2246 int snd_seq_delete_kernel_client(int client)
2248 struct snd_seq_client *ptr;
2250 if (snd_BUG_ON(in_interrupt()))
2253 ptr = clientptr(client);
2257 seq_free_client(ptr);
2261 EXPORT_SYMBOL(snd_seq_delete_kernel_client);
2264 * exported, called by kernel clients to enqueue events (w/o blocking)
2266 * RETURN VALUE: zero if succeed, negative if error
2268 int snd_seq_kernel_client_enqueue(int client, struct snd_seq_event *ev,
2269 struct file *file, bool blocking)
2271 struct snd_seq_client *cptr;
2274 if (snd_BUG_ON(!ev))
2277 if (ev->type == SNDRV_SEQ_EVENT_NONE)
2278 return 0; /* ignore this */
2279 if (ev->type == SNDRV_SEQ_EVENT_KERNEL_ERROR)
2280 return -EINVAL; /* quoted events can't be enqueued */
2282 /* fill in client number */
2283 ev->source.client = client;
2285 if (check_event_type_and_length(ev))
2288 cptr = snd_seq_client_use_ptr(client);
2292 if (!cptr->accept_output) {
2294 } else { /* send it */
2295 mutex_lock(&cptr->ioctl_mutex);
2296 result = snd_seq_client_enqueue_event(cptr, ev, file, blocking,
2298 &cptr->ioctl_mutex);
2299 mutex_unlock(&cptr->ioctl_mutex);
2302 snd_seq_client_unlock(cptr);
2305 EXPORT_SYMBOL(snd_seq_kernel_client_enqueue);
2308 * exported, called by kernel clients to dispatch events directly to other
2309 * clients, bypassing the queues. Event time-stamp will be updated.
2311 * RETURN VALUE: negative = delivery failed,
2312 * zero, or positive: the number of delivered events
2314 int snd_seq_kernel_client_dispatch(int client, struct snd_seq_event * ev,
2315 int atomic, int hop)
2317 struct snd_seq_client *cptr;
2320 if (snd_BUG_ON(!ev))
2323 /* fill in client number */
2324 ev->queue = SNDRV_SEQ_QUEUE_DIRECT;
2325 ev->source.client = client;
2327 if (check_event_type_and_length(ev))
2330 cptr = snd_seq_client_use_ptr(client);
2334 if (!cptr->accept_output)
2337 result = snd_seq_deliver_event(cptr, ev, atomic, hop);
2339 snd_seq_client_unlock(cptr);
2342 EXPORT_SYMBOL(snd_seq_kernel_client_dispatch);
2345 * snd_seq_kernel_client_ctl - operate a command for a client with data in
2347 * @clientid: A numerical ID for a client.
2348 * @cmd: An ioctl(2) command for ALSA sequencer operation.
2349 * @arg: A pointer to data in kernel space.
2351 * Against its name, both kernel/application client can be handled by this
2352 * kernel API. A pointer of 'arg' argument should be in kernel space.
2354 * Return: 0 at success. Negative error code at failure.
2356 int snd_seq_kernel_client_ctl(int clientid, unsigned int cmd, void *arg)
2358 const struct ioctl_handler *handler;
2359 struct snd_seq_client *client;
2361 client = clientptr(clientid);
2365 for (handler = ioctl_handlers; handler->cmd > 0; ++handler) {
2366 if (handler->cmd == cmd)
2367 return handler->func(client, arg);
2370 pr_debug("ALSA: seq unknown ioctl() 0x%x (type='%c', number=0x%02x)\n",
2371 cmd, _IOC_TYPE(cmd), _IOC_NR(cmd));
2374 EXPORT_SYMBOL(snd_seq_kernel_client_ctl);
2376 /* exported (for OSS emulator) */
2377 int snd_seq_kernel_client_write_poll(int clientid, struct file *file, poll_table *wait)
2379 struct snd_seq_client *client;
2381 client = clientptr(clientid);
2385 if (! snd_seq_write_pool_allocated(client))
2387 if (snd_seq_pool_poll_wait(client->pool, file, wait))
2391 EXPORT_SYMBOL(snd_seq_kernel_client_write_poll);
2393 /*---------------------------------------------------------------------------*/
2395 #ifdef CONFIG_SND_PROC_FS
2399 static void snd_seq_info_dump_subscribers(struct snd_info_buffer *buffer,
2400 struct snd_seq_port_subs_info *group,
2401 int is_src, char *msg)
2403 struct list_head *p;
2404 struct snd_seq_subscribers *s;
2407 down_read(&group->list_mutex);
2408 if (list_empty(&group->list_head)) {
2409 up_read(&group->list_mutex);
2412 snd_iprintf(buffer, msg);
2413 list_for_each(p, &group->list_head) {
2415 s = list_entry(p, struct snd_seq_subscribers, src_list);
2417 s = list_entry(p, struct snd_seq_subscribers, dest_list);
2419 snd_iprintf(buffer, ", ");
2420 snd_iprintf(buffer, "%d:%d",
2421 is_src ? s->info.dest.client : s->info.sender.client,
2422 is_src ? s->info.dest.port : s->info.sender.port);
2423 if (s->info.flags & SNDRV_SEQ_PORT_SUBS_TIMESTAMP)
2424 snd_iprintf(buffer, "[%c:%d]", ((s->info.flags & SNDRV_SEQ_PORT_SUBS_TIME_REAL) ? 'r' : 't'), s->info.queue);
2425 if (group->exclusive)
2426 snd_iprintf(buffer, "[ex]");
2428 up_read(&group->list_mutex);
2429 snd_iprintf(buffer, "\n");
2432 #define FLAG_PERM_RD(perm) ((perm) & SNDRV_SEQ_PORT_CAP_READ ? ((perm) & SNDRV_SEQ_PORT_CAP_SUBS_READ ? 'R' : 'r') : '-')
2433 #define FLAG_PERM_WR(perm) ((perm) & SNDRV_SEQ_PORT_CAP_WRITE ? ((perm) & SNDRV_SEQ_PORT_CAP_SUBS_WRITE ? 'W' : 'w') : '-')
2434 #define FLAG_PERM_EX(perm) ((perm) & SNDRV_SEQ_PORT_CAP_NO_EXPORT ? '-' : 'e')
2436 #define FLAG_PERM_DUPLEX(perm) ((perm) & SNDRV_SEQ_PORT_CAP_DUPLEX ? 'X' : '-')
2438 static void snd_seq_info_dump_ports(struct snd_info_buffer *buffer,
2439 struct snd_seq_client *client)
2441 struct snd_seq_client_port *p;
2443 mutex_lock(&client->ports_mutex);
2444 list_for_each_entry(p, &client->ports_list_head, list) {
2445 snd_iprintf(buffer, " Port %3d : \"%s\" (%c%c%c%c)\n",
2446 p->addr.port, p->name,
2447 FLAG_PERM_RD(p->capability),
2448 FLAG_PERM_WR(p->capability),
2449 FLAG_PERM_EX(p->capability),
2450 FLAG_PERM_DUPLEX(p->capability));
2451 snd_seq_info_dump_subscribers(buffer, &p->c_src, 1, " Connecting To: ");
2452 snd_seq_info_dump_subscribers(buffer, &p->c_dest, 0, " Connected From: ");
2454 mutex_unlock(&client->ports_mutex);
2458 /* exported to seq_info.c */
2459 void snd_seq_info_clients_read(struct snd_info_entry *entry,
2460 struct snd_info_buffer *buffer)
2463 struct snd_seq_client *client;
2465 snd_iprintf(buffer, "Client info\n");
2466 snd_iprintf(buffer, " cur clients : %d\n", client_usage.cur);
2467 snd_iprintf(buffer, " peak clients : %d\n", client_usage.peak);
2468 snd_iprintf(buffer, " max clients : %d\n", SNDRV_SEQ_MAX_CLIENTS);
2469 snd_iprintf(buffer, "\n");
2471 /* list the client table */
2472 for (c = 0; c < SNDRV_SEQ_MAX_CLIENTS; c++) {
2473 client = snd_seq_client_use_ptr(c);
2476 if (client->type == NO_CLIENT) {
2477 snd_seq_client_unlock(client);
2481 snd_iprintf(buffer, "Client %3d : \"%s\" [%s]\n",
2483 client->type == USER_CLIENT ? "User" : "Kernel");
2484 snd_seq_info_dump_ports(buffer, client);
2485 if (snd_seq_write_pool_allocated(client)) {
2486 snd_iprintf(buffer, " Output pool :\n");
2487 snd_seq_info_pool(buffer, client->pool, " ");
2489 if (client->type == USER_CLIENT && client->data.user.fifo &&
2490 client->data.user.fifo->pool) {
2491 snd_iprintf(buffer, " Input pool :\n");
2492 snd_seq_info_pool(buffer, client->data.user.fifo->pool, " ");
2494 snd_seq_client_unlock(client);
2497 #endif /* CONFIG_SND_PROC_FS */
2499 /*---------------------------------------------------------------------------*/
2506 static const struct file_operations snd_seq_f_ops =
2508 .owner = THIS_MODULE,
2509 .read = snd_seq_read,
2510 .write = snd_seq_write,
2511 .open = snd_seq_open,
2512 .release = snd_seq_release,
2513 .llseek = no_llseek,
2514 .poll = snd_seq_poll,
2515 .unlocked_ioctl = snd_seq_ioctl,
2516 .compat_ioctl = snd_seq_ioctl_compat,
2519 static struct device seq_dev;
2522 * register sequencer device
2524 int __init snd_sequencer_device_init(void)
2528 snd_device_initialize(&seq_dev, NULL);
2529 dev_set_name(&seq_dev, "seq");
2531 mutex_lock(®ister_mutex);
2532 err = snd_register_device(SNDRV_DEVICE_TYPE_SEQUENCER, NULL, 0,
2533 &snd_seq_f_ops, NULL, &seq_dev);
2534 mutex_unlock(®ister_mutex);
2536 put_device(&seq_dev);
2546 * unregister sequencer device
2548 void snd_sequencer_device_done(void)
2550 snd_unregister_device(&seq_dev);
2551 put_device(&seq_dev);