Linux Kernel  3.7.1
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
seq_ports.h
Go to the documentation of this file.
1 /*
2  * ALSA sequencer Ports
3  * Copyright (c) 1998 by Frank van de Pol <[email protected]>
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 callback_all : 1;
77  unsigned int closing : 1;
78  unsigned int timestamping: 1;
79  unsigned int time_real: 1;
80  int time_queue;
81 
82  /* capability, inport, output, sync */
83  unsigned int capability; /* port capability bits */
84  unsigned int type; /* port type bits */
85 
86  /* supported channels */
87  int midi_channels;
88  int midi_voices;
89  int synth_voices;
90 
91 };
92 
93 struct snd_seq_client;
94 
95 /* return pointer to port structure and lock port */
96 struct snd_seq_client_port *snd_seq_port_use_ptr(struct snd_seq_client *client, int num);
97 
98 /* search for next port - port is locked if found */
99 struct snd_seq_client_port *snd_seq_port_query_nearest(struct snd_seq_client *client,
100  struct snd_seq_port_info *pinfo);
101 
102 /* unlock the port */
103 #define snd_seq_port_unlock(port) snd_use_lock_free(&(port)->use_lock)
104 
105 /* create a port, port number is returned (-1 on failure) */
106 struct snd_seq_client_port *snd_seq_create_port(struct snd_seq_client *client, int port_index);
107 
108 /* delete a port */
109 int snd_seq_delete_port(struct snd_seq_client *client, int port);
110 
111 /* delete all ports */
112 int snd_seq_delete_all_ports(struct snd_seq_client *client);
113 
114 /* set port info fields */
115 int snd_seq_set_port_info(struct snd_seq_client_port *port,
116  struct snd_seq_port_info *info);
117 
118 /* get port info fields */
119 int snd_seq_get_port_info(struct snd_seq_client_port *port,
120  struct snd_seq_port_info *info);
121 
122 /* add subscriber to subscription list */
123 int snd_seq_port_connect(struct snd_seq_client *caller,
124  struct snd_seq_client *s, struct snd_seq_client_port *sp,
125  struct snd_seq_client *d, struct snd_seq_client_port *dp,
126  struct snd_seq_port_subscribe *info);
127 
128 /* remove subscriber from subscription list */
129 int snd_seq_port_disconnect(struct snd_seq_client *caller,
130  struct snd_seq_client *s, struct snd_seq_client_port *sp,
131  struct snd_seq_client *d, struct snd_seq_client_port *dp,
132  struct snd_seq_port_subscribe *info);
133 
134 /* subscribe port */
135 int snd_seq_port_subscribe(struct snd_seq_client_port *port,
136  struct snd_seq_port_subscribe *info);
137 
138 /* get matched subscriber */
139 struct snd_seq_subscribers *snd_seq_port_get_subscription(struct snd_seq_port_subs_info *src_grp,
140  struct snd_seq_addr *dest_addr);
141 
142 #endif
Generated on Thu Jan 10 2013 15:04:06 for Linux Kernel by   doxygen 1.8.2