sound/core/seq/seq_ports.h

   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 struct snd_seq_subscribers *snd_seq_port_get_subscription(struct snd_seq_port_subs_info *src_grp,
 139                                                           struct snd_seq_addr *dest_addr);
 140
 141 #endif