mixer.h

   1 /*
   2  * Copyright 2004 Timo Hirvonen
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License as
   6  * published by the Free Software Foundation; either version 2 of the
   7  * License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  17  * 02111-1307, USA.
  18  */
  19
  20 #ifndef _MIXER_H
  21 #define _MIXER_H
  22
  23 #define NR_MIXER_FDS 4
  24
  25 struct mixer_plugin_ops {
  26         int (*init)(void);
  27         int (*exit)(void);
  28         int (*open)(int *volume_max);
  29         int (*close)(void);
  30         int (*get_fds)(int *fds);
  31         int (*set_volume)(int l, int r);
  32         int (*get_volume)(int *l, int *r);
  33         int (*set_option)(int key, const char *val);
  34         int (*get_option)(int key, char **val);
  35 };
  36
  37 /* symbols exported by plugin */
  38 extern const struct mixer_plugin_ops op_mixer_ops;
  39 extern const char * const op_mixer_options[];
  40
  41 #endif