1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
|
/* $NetBSD: audiovar.h,v 1.3 1995/05/08 22:01:44 brezak Exp $ */
/*
* Copyright (c) 1991-1993 Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the Computer Systems
* Engineering Group at Lawrence Berkeley Laboratory.
* 4. Neither the name of the University nor of the Laboratory may be used
* to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* From: Header: audiovar.h,v 1.3 93/07/18 14:07:25 mccanne Exp (LBL)
*/
/*
* Initial/default block duration is both configurable and patchable.
*/
#ifndef AUDIO_BLK_MS
#define AUDIO_BLK_MS 20 /* 20 ms */
#endif
#ifndef AUDIO_BACKLOG
#define AUDIO_BACKLOG 3 /* 60 ms */
#endif
/*
* Use a single page as the size of the audio ring buffers, so that
* the data won't cross a page boundary. This way the dma carried out
* in the hardware module will be efficient (i.e., at_dma() won't have
* to make a copy).
*/
#ifndef AU_RING_SIZE
#define AU_RING_SIZE NBPG
#endif
#define AU_RING_MOD(k) ((k) & (AU_RING_SIZE - 1))
#define AU_RING_EMPTY(rp) ((rp)->hp == (rp)->tp)
#define AU_RING_FULL(rp) (AU_RING_MOD((rp)->tp + 1) == (rp)->hp)
#define AU_RING_LEN(rp) (AU_RING_MOD((rp)->tp - (rp)->hp))
#define AU_RING_INIT(rp) { \
(rp)->nblk = (rp)->au_stamp = 0; \
(rp)->hp = (rp)->tp = (rp)->bp; \
}
struct audio_buffer {
u_char *hp; /* head */
u_char *tp; /* tail */
u_char *bp; /* start of buffer */
u_char *ep; /* end of buffer */
int nblk; /* number of active blocks in buffer */
int maxblk; /* max # of active blocks in buffer */
u_long au_stamp; /* number of audio samples read/written */
u_short cb_pause; /* io paused */
u_long cb_drops; /* missed samples from over/underrun */
u_long cb_pdrops; /* paused samples */
};
/*
* Software state, per audio device.
*/
struct audio_softc {
void *hw_hdl; /* Hardware driver handle */
struct audio_hw_if *hw_if; /* Hardware interface */
u_char sc_open; /* single use device */
#define AUOPEN_READ 0x01
#define AUOPEN_WRITE 0x02
u_char sc_mode; /* bitmask for RECORD/PLAY */
struct selinfo sc_wsel; /* write selector */
struct selinfo sc_rsel; /* read selector */
/* Sleep channels for reading and writing. */
int sc_rchan;
int sc_wchan;
/* Ring buffers, separate for record and play. */
struct audio_buffer rr; /* Record ring */
struct audio_buffer pr; /* Play ring */
u_char sc_rbus; /* input dma in progress */
u_char sc_pbus; /* output dma in progress */
u_long sc_wseek; /* timestamp of last frame written */
u_long sc_rseek; /* timestamp of last frame read */
int sc_blksize; /* recv block (chunk) size in bytes */
int sc_smpl_in_blk; /* # samples in a block */
int sc_50ms; /* # of samples for 50ms? */
int sc_backlog; /* # blks of xmit backlog to generate */
int sc_lowat; /* xmit low water mark (for wakeup) */
int sc_hiwat; /* xmit high water mark (for wakeup) */
int sc_rblks; /* number of phantom record blocks */
int sc_pencoding; /* current encoding; play */
int sc_rencoding; /* current encoding; record */
};
|
