drivers/media/radio/radio-gemtek.c

   1 /* GemTek radio card driver for Linux (C) 1998 Jonas Munsin <jmunsin@iki.fi>
   2  *
   3  * GemTek hasn't released any specs on the card, so the protocol had to
   4  * be reverse engineered with dosemu.
   5  *
   6  * Besides the protocol changes, this is mostly a copy of:
   7  *
   8  *    RadioTrack II driver for Linux radio support (C) 1998 Ben Pfaff
   9  *
  10  *    Based on RadioTrack I/RadioReveal (C) 1997 M. Kirkwood
  11  *    Converted to new API by Alan Cox <Alan.Cox@linux.org>
  12  *    Various bugfixes and enhancements by Russell Kroll <rkroll@exploits.org>
  13  *
  14  * TODO: Allow for more than one of these foolish entities :-)
  15  *
  16  */
  17
  18 #include <linux/module.h>       /* Modules                      */
  19 #include <linux/init.h>         /* Initdata                     */
  20 #include <linux/ioport.h>       /* request_region               */
  21 #include <linux/delay.h>        /* udelay                       */
  22 #include <asm/io.h>             /* outb, outb_p                 */
  23 #include <asm/uaccess.h>        /* copy to/from user            */
  24 #include <linux/videodev.h>     /* kernel radio structs         */
  25 #include <media/v4l2-common.h>
  26 #include <linux/config.h>       /* CONFIG_RADIO_GEMTEK_PORT     */
  27 #include <linux/spinlock.h>
  28
  29 #ifndef CONFIG_RADIO_GEMTEK_PORT
  30 #define CONFIG_RADIO_GEMTEK_PORT -1
  31 #endif
  32
  33 static int io = CONFIG_RADIO_GEMTEK_PORT;
  34 static int radio_nr = -1;
  35 static spinlock_t lock;
  36
  37 struct gemtek_device
  38 {
  39         int port;
  40         unsigned long curfreq;
  41         int muted;
  42 };
  43
  44
  45 /* local things */
  46
  47 /* the correct way to mute the gemtek may be to write the last written
  48  * frequency || 0x10, but just writing 0x10 once seems to do it as well
  49  */
  50 static void gemtek_mute(struct gemtek_device *dev)
  51 {
  52         if(dev->muted)
  53                 return;
  54         spin_lock(&lock);
  55         outb(0x10, io);
  56         spin_unlock(&lock);
  57         dev->muted = 1;
  58 }
  59
  60 static void gemtek_unmute(struct gemtek_device *dev)
  61 {
  62         if(dev->muted == 0)
  63                 return;
  64         spin_lock(&lock);
  65         outb(0x20, io);
  66         spin_unlock(&lock);
  67         dev->muted = 0;
  68 }
  69
  70 static void zero(void)
  71 {
  72         outb_p(0x04, io);
  73         udelay(5);
  74         outb_p(0x05, io);
  75         udelay(5);
  76 }
  77
  78 static void one(void)
  79 {
  80         outb_p(0x06, io);
  81         udelay(5);
  82         outb_p(0x07, io);
  83         udelay(5);
  84 }
  85
  86 static int gemtek_setfreq(struct gemtek_device *dev, unsigned long freq)
  87 {
  88         int i;
  89
  90 /*        freq = 78.25*((float)freq/16000.0 + 10.52); */
  91
  92         freq /= 16;
  93         freq += 10520;
  94         freq *= 7825;
  95         freq /= 100000;
  96
  97         spin_lock(&lock);
  98
  99         /* 2 start bits */
 100         outb_p(0x03, io);
 101         udelay(5);
 102         outb_p(0x07, io);
 103         udelay(5);
 104
 105         /* 28 frequency bits (lsb first) */
 106         for (i = 0; i < 14; i++)
 107                 if (freq & (1 << i))
 108                         one();
 109                 else
 110                         zero();
 111         /* 36 unknown bits */
 112         for (i = 0; i < 11; i++)
 113                 zero();
 114         one();
 115         for (i = 0; i < 4; i++)
 116                 zero();
 117         one();
 118         zero();
 119
 120         /* 2 end bits */
 121         outb_p(0x03, io);
 122         udelay(5);
 123         outb_p(0x07, io);
 124         udelay(5);
 125
 126         spin_unlock(&lock);
 127
 128         return 0;
 129 }
 130
 131 static int gemtek_getsigstr(struct gemtek_device *dev)
 132 {
 133         spin_lock(&lock);
 134         inb(io);
 135         udelay(5);
 136         spin_unlock(&lock);
 137         if (inb(io) & 8)                /* bit set = no signal present */
 138                 return 0;
 139         return 1;               /* signal present */
 140 }
 141
 142 static int gemtek_do_ioctl(struct inode *inode, struct file *file,
 143                            unsigned int cmd, void *arg)
 144 {
 145         struct video_device *dev = video_devdata(file);
 146         struct gemtek_device *rt=dev->priv;
 147
 148         switch(cmd)
 149         {
 150                 case VIDIOCGCAP:
 151                 {
 152                         struct video_capability *v = arg;
 153                         memset(v,0,sizeof(*v));
 154                         v->type=VID_TYPE_TUNER;
 155                         v->channels=1;
 156                         v->audios=1;
 157                         strcpy(v->name, "GemTek");
 158                         return 0;
 159                 }
 160                 case VIDIOCGTUNER:
 161                 {
 162                         struct video_tuner *v = arg;
 163                         if(v->tuner)    /* Only 1 tuner */
 164                                 return -EINVAL;
 165                         v->rangelow=87*16000;
 166                         v->rangehigh=108*16000;
 167                         v->flags=VIDEO_TUNER_LOW;
 168                         v->mode=VIDEO_MODE_AUTO;
 169                         v->signal=0xFFFF*gemtek_getsigstr(rt);
 170                         strcpy(v->name, "FM");
 171                         return 0;
 172                 }
 173                 case VIDIOCSTUNER:
 174                 {
 175                         struct video_tuner *v = arg;
 176                         if(v->tuner!=0)
 177                                 return -EINVAL;
 178                         /* Only 1 tuner so no setting needed ! */
 179                         return 0;
 180                 }
 181                 case VIDIOCGFREQ:
 182                 {
 183                         unsigned long *freq = arg;
 184                         *freq = rt->curfreq;
 185                         return 0;
 186                 }
 187                 case VIDIOCSFREQ:
 188                 {
 189                         unsigned long *freq = arg;
 190                         rt->curfreq = *freq;
 191                         /* needs to be called twice in order for getsigstr to work */
 192                         gemtek_setfreq(rt, rt->curfreq);
 193                         gemtek_setfreq(rt, rt->curfreq);
 194                         return 0;
 195                 }
 196                 case VIDIOCGAUDIO:
 197                 {
 198                         struct video_audio *v = arg;
 199                         memset(v,0, sizeof(*v));
 200                         v->flags|=VIDEO_AUDIO_MUTABLE;
 201                         v->volume=1;
 202                         v->step=65535;
 203                         strcpy(v->name, "Radio");
 204                         return 0;
 205                 }
 206                 case VIDIOCSAUDIO:
 207                 {
 208                         struct video_audio *v = arg;
 209                         if(v->audio)
 210                                 return -EINVAL;
 211
 212                         if(v->flags&VIDEO_AUDIO_MUTE)
 213                                 gemtek_mute(rt);
 214                         else
 215                                 gemtek_unmute(rt);
 216
 217                         return 0;
 218                 }
 219                 default:
 220                         return -ENOIOCTLCMD;
 221         }
 222 }
 223
 224 static int gemtek_ioctl(struct inode *inode, struct file *file,
 225                         unsigned int cmd, unsigned long arg)
 226 {
 227         return video_usercopy(inode, file, cmd, arg, gemtek_do_ioctl);
 228 }
 229
 230 static struct gemtek_device gemtek_unit;
 231
 232 static struct file_operations gemtek_fops = {
 233         .owner          = THIS_MODULE,
 234         .open           = video_exclusive_open,
 235         .release        = video_exclusive_release,
 236         .ioctl          = gemtek_ioctl,
 237         .compat_ioctl   = v4l_compat_ioctl32,
 238         .llseek         = no_llseek,
 239 };
 240
 241 static struct video_device gemtek_radio=
 242 {
 243         .owner          = THIS_MODULE,
 244         .name           = "GemTek radio",
 245         .type           = VID_TYPE_TUNER,
 246         .hardware       = VID_HARDWARE_GEMTEK,
 247         .fops           = &gemtek_fops,
 248 };
 249
 250 static int __init gemtek_init(void)
 251 {
 252         if(io==-1)
 253         {
 254                 printk(KERN_ERR "You must set an I/O address with io=0x20c, io=0x30c, io=0x24c or io=0x34c (io=0x020c or io=0x248 for the combined sound/radiocard)\n");
 255                 return -EINVAL;
 256         }
 257
 258         if (!request_region(io, 4, "gemtek"))
 259         {
 260                 printk(KERN_ERR "gemtek: port 0x%x already in use\n", io);
 261                 return -EBUSY;
 262         }
 263
 264         gemtek_radio.priv=&gemtek_unit;
 265
 266         if(video_register_device(&gemtek_radio, VFL_TYPE_RADIO, radio_nr)==-1)
 267         {
 268                 release_region(io, 4);
 269                 return -EINVAL;
 270         }
 271         printk(KERN_INFO "GemTek Radio Card driver.\n");
 272
 273         spin_lock_init(&lock);
 274
 275         /* this is _maybe_ unnecessary */
 276         outb(0x01, io);
 277
 278         /* mute card - prevents noisy bootups */
 279         gemtek_unit.muted = 0;
 280         gemtek_mute(&gemtek_unit);
 281
 282         return 0;
 283 }
 284
 285 MODULE_AUTHOR("Jonas Munsin");
 286 MODULE_DESCRIPTION("A driver for the GemTek Radio Card");
 287 MODULE_LICENSE("GPL");
 288
 289 module_param(io, int, 0);
 290 MODULE_PARM_DESC(io, "I/O address of the GemTek card (0x20c, 0x30c, 0x24c or 0x34c (0x20c or 0x248 have been reported to work for the combined sound/radiocard)).");
 291 module_param(radio_nr, int, 0);
 292
 293 static void __exit gemtek_cleanup(void)
 294 {
 295         video_unregister_device(&gemtek_radio);
 296         release_region(io,4);
 297 }
 298
 299 module_init(gemtek_init);
 300 module_exit(gemtek_cleanup);
 301
 302 /*
 303   Local variables:
 304   compile-command: "gcc -c -DMODVERSIONS -D__KERNEL__ -DMODULE -O6 -Wall -Wstrict-prototypes -I /home/blp/tmp/linux-2.1.111-rtrack/include radio-rtrack2.c"
 305   End:
 306 */