fm.c

   1 /* fm.c - simple v4l compatible tuner for radio cards
   2
   3    Copyright (C) 1998  Russell Kroll <rkroll@exploits.org>
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 2 of the License, or
   8    (at your option) any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program; if not, write to the Free Software
  17    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18  */
  19
  20 #include <math.h>
  21 #include <errno.h>
  22 #include <stdio.h>
  23 #include <fcntl.h>
  24 #include <stdlib.h>
  25 #include <unistd.h>
  26 #include <getopt.h>
  27 #include <string.h>
  28 #include <asm/types.h>
  29 #include <sys/ioctl.h>
  30 #include <linux/videodev.h>
  31
  32 void help(char *prog)
  33 {
  34         printf("usage: %s [-h] [-o] [-q] [-d <dev>] [-t <tuner>] <freq>|on|off [<volume>]\n", prog);
  35         printf("\n");
  36         printf("  -h         display this help\n");
  37         printf("  -o         override frequency range limits of card\n");
  38         printf("  -q         quiet mode\n");
  39         printf("  -d <dev>   select device (default: /dev/radio0)\n");
  40         printf("  -t <tuner> select tuner (default: 0)\n");
  41         printf("  <freq>     frequency in MHz (i.e. 94.3)\n");
  42         printf("  on         turn radio on\n");
  43         printf("  off        turn radio off (mute)\n");
  44         printf("  +          increase volume\n");
  45         printf("  -          decrease volume\n");
  46         printf("  <volume>   intensity (0-65535)\n");
  47         exit(0);
  48 }
  49
  50 void getconfig(int *defaultvol, int *increment)
  51 {
  52         FILE    *conf;
  53         char    buf[256], fn[256];
  54
  55         sprintf(fn, "%s/.fmrc", getenv("HOME"));
  56         conf = fopen(fn, "r");
  57
  58         if (!conf)
  59                 return;
  60
  61         while(fgets(buf, sizeof(buf), conf)) {
  62                 buf[strlen(buf)-1] = 0;
  63                 if (!strncmp(buf, "VOL", 3))
  64                         sscanf(buf, "%*s %i", defaultvol);
  65                 if (!strncmp(buf, "INCR", 3))
  66                         sscanf(buf, "%*s %i", increment);
  67         }
  68
  69         fclose(conf);
  70 }
  71
  72 int main(int argc, char **argv)
  73 {
  74         int             fd, ret, tunevol, quiet=0, i, override = 0;
  75         int             defaultvol = 8192;      /* default volume = 12.5% */
  76         int             increment = 6554;       /* default change = 10% */
  77         double          fact;
  78         unsigned long   freq;
  79         struct          video_audio va;
  80         struct          video_tuner vt;
  81         char            *progname;
  82         int             tuner = 0;
  83         char    *dev = NULL;
  84
  85         /* need at least a frequency */
  86         if (argc < 2) {
  87                 printf ("usage: %s [-h] [-o] [-q] [-d <dev>] [-t <tuner>] <freq>|on|off [<volume>]\n", argv[0]);
  88                 exit (1);
  89         }
  90
  91         progname = argv[0];     /* used after getopt munges argv[] */
  92
  93         getconfig(&defaultvol, &increment);
  94
  95         while ((i = getopt(argc, argv, "+qhot:d:")) != EOF) {
  96                 switch (i) {
  97                         case 'q':
  98                                 quiet = 1;
  99                                 break;
 100                         case 'o':
 101                                 override = 1;
 102                                 break;
 103                         case 't':
 104                                 tuner = atoi(optarg);
 105                                 break;
 106                         case 'd':
 107                                 dev = strdup(optarg);
 108                                 break;
 109                         case 'h':
 110                         default:
 111                                 help(argv[0]);
 112                                 break;
 113                 }
 114         }
 115
 116         argc -= optind;
 117         argv += optind;
 118
 119         if (argc == 0)          /* no frequency, on|off, or +|- given */
 120                 help(progname);
 121
 122         if (argc == 2)
 123                 tunevol = atoi(argv[1]);
 124         else
 125                 tunevol = defaultvol;
 126
 127         if (!dev)
 128                 dev = strdup("/dev/radio0");    /* use default */
 129
 130         fd = open(dev, O_RDONLY);
 131         if (fd < 0) {
 132                 fprintf(stderr, "Unable to open %s: %s\n", dev, strerror(errno));
 133                 exit(1);
 134         }
 135
 136         if (!strcmp("off", argv[0])) {          /* mute the radio */
 137                 va.audio = 0;
 138                 va.volume = 0;
 139                 va.flags = VIDEO_AUDIO_MUTE;
 140                 ret = ioctl(fd, VIDIOCSAUDIO, &va);
 141                 if (ret < 0) {
 142                         perror("ioctl VIDIOCSAUDIO");
 143                         exit(1);
 144                 }
 145
 146                 if (!quiet)
 147                         printf ("Radio muted\n");
 148                 exit(0);
 149         }
 150
 151         if (!strcmp("on", argv[0])) {           /* turn radio on */
 152                 va.audio = 0;
 153                 va.volume = tunevol;
 154                 va.flags = 0;
 155                 ret = ioctl(fd, VIDIOCSAUDIO, &va);
 156                 if (ret < 0) {
 157                         perror("ioctl VIDIOCSAUDIO");
 158                         exit(1);
 159                 }
 160
 161                 if (!quiet)
 162                         printf("Radio on at %2.2f%% volume\n",
 163                               (tunevol / 655.36));
 164                 exit(0);
 165         }
 166
 167         ret = ioctl(fd, VIDIOCGAUDIO, &va);
 168         if (ret < 0) {
 169                 perror("ioctl VIDIOCGAUDIO");
 170                 exit(1);
 171         }
 172
 173         if (argv[0][0] == '+') {                /* volume up */
 174                 if ((va.volume + increment) > 65535)
 175                         va.volume = 65535;      /* catch overflows in __u16 */
 176                 else
 177                         va.volume += increment;
 178
 179                 if (!quiet)
 180                         printf("Setting volume to %2.2f%%\n",
 181                               (va.volume / 655.35));
 182
 183                 ret = ioctl (fd, VIDIOCSAUDIO, &va);
 184                 if (ret < 0) {
 185                         perror("ioctl VIDIOCSAUDIO");
 186                         exit(1);
 187                 }
 188
 189                 exit (0);
 190         }
 191
 192         if (argv[0][0] == '-') {                /* volume down */
 193                 if ((va.volume - increment) < 0)
 194                         va.volume = 0;          /* catch negative numbers */
 195                 else
 196                         va.volume -= increment;
 197
 198                 if (!quiet)
 199                         printf("Setting volume to %2.2f%%\n",
 200                                 (va.volume / 655.35));
 201
 202                 ret = ioctl (fd, VIDIOCSAUDIO, &va);
 203                 if (ret < 0) {
 204                         perror("ioctl VIDIOCSAUDIO");
 205                         exit(1);
 206                 }
 207
 208                 exit (0);
 209         }
 210
 211         /* at this point, we are trying to tune to a frequency */
 212
 213         vt.tuner = tuner;
 214         ret = ioctl(fd, VIDIOCSTUNER, &vt);     /* set tuner # */
 215         if (ret < 0) {
 216                 perror("ioctl VIDIOCSTUNER");
 217                 exit(1);
 218         }
 219
 220         ret = ioctl(fd, VIDIOCGTUNER, &vt);     /* get frequency range */
 221         if (ret < 0) {
 222                 perror("ioctl VIDIOCGTUNER");
 223                 exit(1);
 224         }
 225
 226         if ((ret == -1) || ((vt.flags & VIDEO_TUNER_LOW) == 0))
 227                 fact = 16.;
 228         else
 229                 fact = 16000.;
 230
 231         freq = ceil(atof(argv[0]) * fact);      /* rounding up matters */
 232
 233         if ((freq < vt.rangelow) || (freq > vt.rangehigh)) {
 234                 if (override == 0) {
 235                         printf("Frequency %2.1f out of range (%2.1f - %2.1f MHz)\n",
 236                               (freq / fact), (vt.rangelow / fact),
 237                               (vt.rangehigh / fact));
 238                         exit(1);
 239                 }
 240         }
 241
 242         /* frequency sanity checked, proceed */
 243         ret = ioctl(fd, VIDIOCSFREQ, &freq);
 244         if (ret < 0) {
 245                 perror("ioctl VIDIOCSFREQ");
 246                 exit (1);
 247         }
 248
 249         va.audio = 0;
 250         va.volume = tunevol;
 251         va.flags = 0;
 252         va.mode = VIDEO_SOUND_STEREO;
 253
 254         ret = ioctl(fd, VIDIOCSAUDIO, &va);     /* set the volume */
 255         if (ret < 0) {
 256                 perror("ioctl VIDIOCSAUDIO");
 257                 exit(1);
 258         }
 259
 260         if (!quiet)
 261                 printf ("Radio tuned to %2.1f MHz at %2.2f%% volume\n",
 262                         (freq / fact), (tunevol / 655.35));
 263
 264         return 0;
 265 }