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
|
/* lowlevel.c
* Contains functions for manipulating the radio card through
* the kernel interface
*/
/* (c) 1998 by Keith Wesolowski (wesolows@cs.unr.edu)
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <unistd.h>
#include <math.h>
#include <fcntl.h>
#include <linux/videodev.h>
#include <sys/ioctl.h>
#include "gradio.h"
extern radio_status gr_stat;
/* Determine and return the appropriate frequency multiplier for
the first tuner on the open video device with handle FD. */
double gradio_get_freq_fact (void)
{
struct video_tuner tuner;
tuner.tuner = 0;
if (ioctl (gr_stat.fd, VIDIOCGTUNER, &tuner) < 0)
return .016;
if ((tuner.flags & VIDEO_TUNER_LOW) == 0)
return .016;
return 16;
}
int gradio_setfreq (int fr)
{
struct video_tuner v;
struct video_audio va;
unsigned long xl_freq;
if (fr > GR_FREQ_MAX)
fr = GR_FREQ_MAX;
if (fr < GR_FREQ_MIN)
fr = GR_FREQ_MIN;
xl_freq = (unsigned long)(fr*gradio_get_freq_fact ()
+ 0.5);
va.volume = gr_stat.vol * (65535/(GR_VOL_MAX-GR_VOL_MIN));
va.audio = 0;
va.flags = VIDEO_AUDIO_VOLUME|(gr_stat.muted ? VIDEO_AUDIO_MUTE : 0);
v.tuner = 0;
ioctl (gr_stat.fd, VIDIOCSFREQ, &xl_freq);
ioctl (gr_stat.fd, VIDIOCGTUNER, &v);
ioctl (gr_stat.fd, VIDIOCSAUDIO, &va);
gr_stat.tuned = (v.signal != 0);
return (gr_stat.freq = fr);
}
int gradio_setvol (int lvl)
{
struct video_audio va;
if (lvl > GR_VOL_MAX)
lvl = GR_VOL_MAX;
if (lvl < GR_VOL_MIN)
lvl = GR_VOL_MIN;
va.flags = VIDEO_AUDIO_VOLUME|(gr_stat.muted ? VIDEO_AUDIO_MUTE : 0);
va.audio = 0;
va.volume = rint (lvl * (65535./(GR_VOL_MAX-GR_VOL_MIN)));
ioctl (gr_stat.fd, VIDIOCSAUDIO, &va);
return (gr_stat.vol = lvl);
}
void gradio_mute (int state)
{
struct video_audio va;
if (state)
va.flags = VIDEO_AUDIO_MUTE;
else {
va.volume = rint (gr_stat.vol * (65535./(GR_VOL_MAX-GR_VOL_MIN)));
va.flags = VIDEO_AUDIO_VOLUME;
}
va.audio = 0;
ioctl (gr_stat.fd, VIDIOCSAUDIO, &va);
gr_stat.muted = state;
}
|
