1 /* SPDX-License-Identifier: GPL-2.0-or-later */
4 * Copyright (c) 1998 by Frank van de Pol <fvdpol@coil.demon.nl>
6 #ifndef __SND_SEQ_PORTS_H
7 #define __SND_SEQ_PORTS_H
9 #include <sound/seq_kernel.h>
12 /* list of 'exported' ports */
14 /* Client ports that are not exported are still accessible, but are
17 If a port supports SUBSCRIPTION, that port can send events to all
18 subscribersto a special address, with address
19 (queue==SNDRV_SEQ_ADDRESS_SUBSCRIBERS). The message is then send to all
20 recipients that are registered in the subscription list. A typical
21 application for these SUBSCRIPTION events is handling of incoming MIDI
22 data. The port doesn't 'know' what other clients are interested in this
23 message. If for instance a MIDI recording application would like to receive
24 the events from that port, it will first have to subscribe with that port.
28 struct snd_seq_subscribers {
29 struct snd_seq_port_subscribe info; /* additional info */
30 struct list_head src_list; /* link of sources */
31 struct list_head dest_list; /* link of destinations */
35 struct snd_seq_port_subs_info {
36 struct list_head list_head; /* list of subscribed ports */
37 unsigned int count; /* count of subscribers */
38 unsigned int exclusive: 1; /* exclusive mode */
39 struct rw_semaphore list_mutex;
41 int (*open)(void *private_data, struct snd_seq_port_subscribe *info);
42 int (*close)(void *private_data, struct snd_seq_port_subscribe *info);
45 struct snd_seq_client_port {
47 struct snd_seq_addr addr; /* client/port number */
48 struct module *owner; /* owner of this port */
49 char name[64]; /* port name */
50 struct list_head list; /* port list */
51 snd_use_lock_t use_lock;
54 struct snd_seq_port_subs_info c_src; /* read (sender) list */
55 struct snd_seq_port_subs_info c_dest; /* write (dest) list */
57 int (*event_input)(struct snd_seq_event *ev, int direct, void *private_data,
59 void (*private_free)(void *private_data);
61 unsigned int closing : 1;
62 unsigned int timestamping: 1;
63 unsigned int time_real: 1;
66 /* capability, inport, output, sync */
67 unsigned int capability; /* port capability bits */
68 unsigned int type; /* port type bits */
70 /* supported channels */
77 struct snd_seq_client;
79 /* return pointer to port structure and lock port */
80 struct snd_seq_client_port *snd_seq_port_use_ptr(struct snd_seq_client *client, int num);
82 /* search for next port - port is locked if found */
83 struct snd_seq_client_port *snd_seq_port_query_nearest(struct snd_seq_client *client,
84 struct snd_seq_port_info *pinfo);
87 #define snd_seq_port_unlock(port) snd_use_lock_free(&(port)->use_lock)
89 /* create a port, port number is returned (-1 on failure) */
90 struct snd_seq_client_port *snd_seq_create_port(struct snd_seq_client *client, int port_index);
93 int snd_seq_delete_port(struct snd_seq_client *client, int port);
95 /* delete all ports */
96 int snd_seq_delete_all_ports(struct snd_seq_client *client);
98 /* set port info fields */
99 int snd_seq_set_port_info(struct snd_seq_client_port *port,
100 struct snd_seq_port_info *info);
102 /* get port info fields */
103 int snd_seq_get_port_info(struct snd_seq_client_port *port,
104 struct snd_seq_port_info *info);
106 /* add subscriber to subscription list */
107 int snd_seq_port_connect(struct snd_seq_client *caller,
108 struct snd_seq_client *s, struct snd_seq_client_port *sp,
109 struct snd_seq_client *d, struct snd_seq_client_port *dp,
110 struct snd_seq_port_subscribe *info);
112 /* remove subscriber from subscription list */
113 int snd_seq_port_disconnect(struct snd_seq_client *caller,
114 struct snd_seq_client *s, struct snd_seq_client_port *sp,
115 struct snd_seq_client *d, struct snd_seq_client_port *dp,
116 struct snd_seq_port_subscribe *info);
119 int snd_seq_port_subscribe(struct snd_seq_client_port *port,
120 struct snd_seq_port_subscribe *info);
122 /* get matched subscriber */
123 int snd_seq_port_get_subscription(struct snd_seq_port_subs_info *src_grp,
124 struct snd_seq_addr *dest_addr,
125 struct snd_seq_port_subscribe *subs);