xref: /openbmc/linux/sound/core/seq/seq_ports.h (revision ae213c44)
1 /*
2  *   ALSA sequencer Ports
3  *   Copyright (c) 1998 by Frank van de Pol <fvdpol@coil.demon.nl>
4  *
5  *
6  *   This program is free software; you can redistribute it and/or modify
7  *   it under the terms of the GNU General Public License as published by
8  *   the Free Software Foundation; either version 2 of the License, or
9  *   (at your option) any later version.
10  *
11  *   This program is distributed in the hope that it will be useful,
12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  *   GNU General Public License for more details.
15  *
16  *   You should have received a copy of the GNU General Public License
17  *   along with this program; if not, write to the Free Software
18  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
19  *
20  */
21 #ifndef __SND_SEQ_PORTS_H
22 #define __SND_SEQ_PORTS_H
23 
24 #include <sound/seq_kernel.h>
25 #include "seq_lock.h"
26 
27 /* list of 'exported' ports */
28 
29 /* Client ports that are not exported are still accessible, but are
30  anonymous ports.
31 
32  If a port supports SUBSCRIPTION, that port can send events to all
33  subscribersto a special address, with address
34  (queue==SNDRV_SEQ_ADDRESS_SUBSCRIBERS). The message is then send to all
35  recipients that are registered in the subscription list. A typical
36  application for these SUBSCRIPTION events is handling of incoming MIDI
37  data. The port doesn't 'know' what other clients are interested in this
38  message. If for instance a MIDI recording application would like to receive
39  the events from that port, it will first have to subscribe with that port.
40 
41 */
42 
43 struct snd_seq_subscribers {
44 	struct snd_seq_port_subscribe info;	/* additional info */
45 	struct list_head src_list;	/* link of sources */
46 	struct list_head dest_list;	/* link of destinations */
47 	atomic_t ref_count;
48 };
49 
50 struct snd_seq_port_subs_info {
51 	struct list_head list_head;	/* list of subscribed ports */
52 	unsigned int count;		/* count of subscribers */
53 	unsigned int exclusive: 1;	/* exclusive mode */
54 	struct rw_semaphore list_mutex;
55 	rwlock_t list_lock;
56 	int (*open)(void *private_data, struct snd_seq_port_subscribe *info);
57 	int (*close)(void *private_data, struct snd_seq_port_subscribe *info);
58 };
59 
60 struct snd_seq_client_port {
61 
62 	struct snd_seq_addr addr;	/* client/port number */
63 	struct module *owner;		/* owner of this port */
64 	char name[64];			/* port name */
65 	struct list_head list;		/* port list */
66 	snd_use_lock_t use_lock;
67 
68 	/* subscribers */
69 	struct snd_seq_port_subs_info c_src;	/* read (sender) list */
70 	struct snd_seq_port_subs_info c_dest;	/* write (dest) list */
71 
72 	int (*event_input)(struct snd_seq_event *ev, int direct, void *private_data,
73 			   int atomic, int hop);
74 	void (*private_free)(void *private_data);
75 	void *private_data;
76 	unsigned int closing : 1;
77 	unsigned int timestamping: 1;
78 	unsigned int time_real: 1;
79 	int time_queue;
80 
81 	/* capability, inport, output, sync */
82 	unsigned int capability;	/* port capability bits */
83 	unsigned int type;		/* port type bits */
84 
85 	/* supported channels */
86 	int midi_channels;
87 	int midi_voices;
88 	int synth_voices;
89 
90 };
91 
92 struct snd_seq_client;
93 
94 /* return pointer to port structure and lock port */
95 struct snd_seq_client_port *snd_seq_port_use_ptr(struct snd_seq_client *client, int num);
96 
97 /* search for next port - port is locked if found */
98 struct snd_seq_client_port *snd_seq_port_query_nearest(struct snd_seq_client *client,
99 						       struct snd_seq_port_info *pinfo);
100 
101 /* unlock the port */
102 #define snd_seq_port_unlock(port) snd_use_lock_free(&(port)->use_lock)
103 
104 /* create a port, port number is returned (-1 on failure) */
105 struct snd_seq_client_port *snd_seq_create_port(struct snd_seq_client *client, int port_index);
106 
107 /* delete a port */
108 int snd_seq_delete_port(struct snd_seq_client *client, int port);
109 
110 /* delete all ports */
111 int snd_seq_delete_all_ports(struct snd_seq_client *client);
112 
113 /* set port info fields */
114 int snd_seq_set_port_info(struct snd_seq_client_port *port,
115 			  struct snd_seq_port_info *info);
116 
117 /* get port info fields */
118 int snd_seq_get_port_info(struct snd_seq_client_port *port,
119 			  struct snd_seq_port_info *info);
120 
121 /* add subscriber to subscription list */
122 int snd_seq_port_connect(struct snd_seq_client *caller,
123 			 struct snd_seq_client *s, struct snd_seq_client_port *sp,
124 			 struct snd_seq_client *d, struct snd_seq_client_port *dp,
125 			 struct snd_seq_port_subscribe *info);
126 
127 /* remove subscriber from subscription list */
128 int snd_seq_port_disconnect(struct snd_seq_client *caller,
129 			    struct snd_seq_client *s, struct snd_seq_client_port *sp,
130 			    struct snd_seq_client *d, struct snd_seq_client_port *dp,
131 			    struct snd_seq_port_subscribe *info);
132 
133 /* subscribe port */
134 int snd_seq_port_subscribe(struct snd_seq_client_port *port,
135 			   struct snd_seq_port_subscribe *info);
136 
137 /* get matched subscriber */
138 int snd_seq_port_get_subscription(struct snd_seq_port_subs_info *src_grp,
139 				  struct snd_seq_addr *dest_addr,
140 				  struct snd_seq_port_subscribe *subs);
141 
142 #endif
143