1 /* $OpenBSD: pt2254a.h,v 1.1 2002/04/25 04:56:59 mickey Exp $ */
2 /*
3 * Copyright (c) 2002 Vladimir Popov <jumbo@narod.ru>.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
18 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
20 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
21 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
22 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
23 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25 /*
26 * Princeton Technology Corp.'s Electronic Volume Controller IC PT2254A
27 * http://www.princeton.com.tw
28 *
29 * PT2254A is an electronic volume controller IC utilizing CMOS Technology
30 * specially designed for use in audio equipment. It has two built-in
31 * channels making it highly suitable for mono and stereo sound applications.
32 * Through the specially designated signals that are applied externally to
33 * the data, clock and strobe input pins, PT2254A can control attenuation
34 * and channel balance.
35 */
36
37 #ifndef _PT2254A_H_
38 #define _PT2254A_H_
39
40 #define PT2254A_MAX_ATTENUATION 68
41 #define PT2254A_ATTENUATION_STEPS 35
42
43 #define PT2254A_REGISTER_LENGTH 18
44
45 #define PT2254A_ATTENUATION_MAJOR_0dB (1 << 0)
46 #define PT2254A_ATTENUATION_MAJOR_10dB (1 << 1)
47 #define PT2254A_ATTENUATION_MAJOR_20dB (1 << 2)
48 #define PT2254A_ATTENUATION_MAJOR_30dB (1 << 3)
49 #define PT2254A_ATTENUATION_MAJOR_40dB (1 << 4)
50 #define PT2254A_ATTENUATION_MAJOR_50dB (1 << 5)
51 #define PT2254A_ATTENUATION_MAJOR_60dB (1 << 6)
52 #define PT2254A_ATTENUATION_MAJOR(x) (1 << x)
53
54 #define PT2254A_ATTENUATION_MINOR_0dB (1 << 7)
55 #define PT2254A_ATTENUATION_MINOR_2dB (1 << 8
56 #define PT2254A_ATTENUATION_MINOR_4dB (1 << 9)
57 #define PT2254A_ATTENUATION_MINOR_6dB (1 << 10)
58 #define PT2254A_ATTENUATION_MINOR_8dB (1 << 11)
59 #define PT2254A_ATTENUATION_MINOR(x) (1 << (7 + x / 2))
60
61 #define PT2254A_EMPTY_BIT (0 << 12)
62
63 #define PT2254A_BOTH_CHANNELS (3 << 13)
64 #define PT2254A_LEFT_CHANNEL (1 << 13)
65 #define PT2254A_RIGHT_CHANNEL (1 << 14)
66
67 #define PT2254A_ZERO_PADDING (0 << 15)
68
69 #define USE_CHANNEL 1
70
71 u_int32_t pt2254a_encode_volume(u_int8_t *, u_int8_t);
72 u_int32_t pt2254a_compose_register(u_int32_t, u_int32_t, int, int);
73
74 #endif /* _PT2254A_H_ */