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>       /* check_region, 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 <linux/config.h>       /* CONFIG_RADIO_GEMTEK_PORT     */
  26 #include <linux/spinlock.h>
  27
  28 #ifndef CONFIG_RADIO_GEMTEK_PORT
  29 #define CONFIG_RADIO_GEMTEK_PORT -1
  30 #endif
  31
  32 static int io = CONFIG_RADIO_GEMTEK_PORT;
  33 static int radio_nr = -1;
  34 static spinlock_t lock;
  35
  36 struct gemtek_device
  37 {
  38         int port;
  39         unsigned long curfreq;
  40         int muted;
  41 };
  42
  43
  44 /* local things */
  45
  46 /* the correct way to mute the gemtek may be to write the last written
  47  * frequency || 0x10, but just writing 0x10 once seems to do it as well
  48  */
  49 static void gemtek_mute(struct gemtek_device *dev)
  50 {
  51         if(dev->muted)
  52                 return;
  53         spin_lock(&lock);
  54         outb(0x10, io);
  55         spin_unlock(&lock);
  56         dev->muted = 1;
  57 }
  58
  59 static void gemtek_unmute(struct gemtek_device *dev)
  60 {
  61         if(dev->muted == 0)
  62                 return;
  63         spin_lock(&lock);
  64         outb(0x20, io);
  65         spin_unlock(&lock);
  66         dev->muted = 0;
  67 }
  68
  69 static void zero(void)
  70 {
  71         outb_p(0x04, io);
  72         udelay(5);
  73         outb_p(0x05, io);
  74         udelay(5);
  75 }
  76
  77 static void one(void)
  78 {
  79         outb_p(0x06, io);
  80         udelay(5);
  81         outb_p(0x07, io);
  82         udelay(5);
  83 }
  84
  85 static int gemtek_setfreq(struct gemtek_device *dev, unsigned long freq)
  86 {
  87         int i;
  88
  89 /*        freq = 78.25*((float)freq/16000.0 + 10.52); */
  90
  91         freq /= 16;
  92         freq += 10520;
  93         freq *= 7825;
  94         freq /= 100000;
  95
  96         spin_lock(&lock);
  97
  98         /* 2 start bits */
  99         outb_p(0x03, io);
 100         udelay(5);
 101         outb_p(0x07, io);
 102         udelay(5);
 103
 104         /* 28 frequency bits (lsb first) */
 105         for (i = 0; i < 14; i++)
 106                 if (freq & (1 << i))
 107                         one();
 108                 else
 109                         zero();
 110         /* 36 unknown bits */
 111         for (i = 0; i < 11; i++)
 112                 zero();
 113         one();
 114         for (i = 0; i < 4; i++)
 115                 zero();
 116         one();
 117         zero();
 118
 119         /* 2 end bits */
 120         outb_p(0x03, io);
 121         udelay(5);
 122         outb_p(0x07, io);
 123         udelay(5);
 124
 125         spin_unlock(&lock);
 126
 127         return 0;
 128 }
 129
 130 static int gemtek_getsigstr(struct gemtek_device *dev)
 131 {
 132         spin_lock(&lock);
 133         inb(io);
 134         udelay(5);
 135         spin_unlock(&lock);
 136         if (inb(io) & 8)                /* bit set = no signal present */
 137                 return 0;
 138         return 1;               /* signal present */
 139 }
 140
 141 static int gemtek_do_ioctl(struct inode *inode, struct file *file,
 142                            unsigned int cmd, void *arg)
 143 {
 144         struct video_device *dev = video_devdata(file);
 145         struct gemtek_device *rt=dev->priv;
 146
 147         switch(cmd)
 148         {
 149                 case VIDIOCGCAP:
 150                 {
 151                         struct video_capability *v = arg;
 152                         memset(v,0,sizeof(*v));
 153                         v->type=VID_TYPE_TUNER;
 154                         v->channels=1;
 155                         v->audios=1;
 156                         strcpy(v->name, "GemTek");
 157                         return 0;
 158                 }
 159                 case VIDIOCGTUNER:
 160                 {
 161                         struct video_tuner *v = arg;
 162                         if(v->tuner)    /* Only 1 tuner */
 163                                 return -EINVAL;
 164                         v->rangelow=87*16000;
 165                         v->rangehigh=108*16000;
 166                         v->flags=VIDEO_TUNER_LOW;
 167                         v->mode=VIDEO_MODE_AUTO;
 168                         v->signal=0xFFFF*gemtek_getsigstr(rt);
 169                         strcpy(v->name, "FM");
 170                         return 0;
 171                 }
 172                 case VIDIOCSTUNER:
 173                 {
 174                         struct video_tuner *v = arg;
 175                         if(v->tuner!=0)
 176                                 return -EINVAL;
 177                         /* Only 1 tuner so no setting needed ! */
 178                         return 0;
 179                 }
 180                 case VIDIOCGFREQ:
 181                 {
 182                         unsigned long *freq = arg;
 183                         *freq = rt->curfreq;
 184                         return 0;
 185                 }
 186                 case VIDIOCSFREQ:
 187                 {
 188                         unsigned long *freq = arg;
 189                         rt->curfreq = *freq;
 190                         /* needs to be called twice in order for getsigstr to work */
 191                         gemtek_setfreq(rt, rt->curfreq);
 192                         gemtek_setfreq(rt, rt->curfreq);
 193                         return 0;
 194                 }
 195                 case VIDIOCGAUDIO:
 196                 {
 197                         struct video_audio *v = arg;
 198                         memset(v,0, sizeof(*v));
 199                         v->flags|=VIDEO_AUDIO_MUTABLE;
 200                         v->volume=1;
 201                         v->step=65535;
 202                         strcpy(v->name, "Radio");
 203                         return 0;
 204                 }
 205                 case VIDIOCSAUDIO:
 206                 {
 207                         struct video_audio *v = arg;
 208                         if(v->audio)
 209                                 return -EINVAL;
 210
 211                         if(v->flags&VIDEO_AUDIO_MUTE)
 212                                 gemtek_mute(rt);
 213                         else
 214                                 gemtek_unmute(rt);
 215
 216                         return 0;
 217                 }
 218                 default:
 219                         return -ENOIOCTLCMD;
 220         }
 221 }
 222
 223 static int gemtek_ioctl(struct inode *inode, struct file *file,
 224                         unsigned int cmd, unsigned long arg)
 225 {
 226         return video_usercopy(inode, file, cmd, arg, gemtek_do_ioctl);
 227 }
 228
 229 static struct gemtek_device gemtek_unit;
 230
 231 static struct file_operations gemtek_fops = {
 232         .owner          = THIS_MODULE,
 233         .open           = video_exclusive_open,
 234         .release        = video_exclusive_release,
 235         .ioctl          = gemtek_ioctl,
 236         .llseek         = no_llseek,
 237 };
 238
 239 static struct video_device gemtek_radio=
 240 {
 241         .owner          = THIS_MODULE,
 242         .name           = "GemTek radio",
 243         .type           = VID_TYPE_TUNER,
 244         .hardware       = VID_HARDWARE_GEMTEK,
 245         .fops           = &gemtek_fops,
 246 };
 247
 248 static int __init gemtek_init(void)
 249 {
 250         if(io==-1)
 251         {
 252                 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");
 253                 return -EINVAL;
 254         }
 255
 256         if (!request_region(io, 4, "gemtek"))
 257         {
 258                 printk(KERN_ERR "gemtek: port 0x%x already in use\n", io);
 259                 return -EBUSY;
 260         }
 261
 262         gemtek_radio.priv=&gemtek_unit;
 263
 264         if(video_register_device(&gemtek_radio, VFL_TYPE_RADIO, radio_nr)==-1)
 265         {
 266                 release_region(io, 4);
 267                 return -EINVAL;
 268         }
 269         printk(KERN_INFO "GemTek Radio Card driver.\n");
 270
 271         spin_lock_init(&lock);
 272
 273         /* this is _maybe_ unnecessary */
 274         outb(0x01, io);
 275
 276         /* mute card - prevents noisy bootups */
 277         gemtek_unit.muted = 0;
 278         gemtek_mute(&gemtek_unit);
 279
 280         return 0;
 281 }
 282
 283 MODULE_AUTHOR("Jonas Munsin");
 284 MODULE_DESCRIPTION("A driver for the GemTek Radio Card");
 285 MODULE_LICENSE("GPL");
 286
 287 module_param(io, int, 0);
 288 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)).");
 289 module_param(radio_nr, int, 0);
 290
 291 static void __exit gemtek_cleanup(void)
 292 {
 293         video_unregister_device(&gemtek_radio);
 294         release_region(io,4);
 295 }
 296
 297 module_init(gemtek_init);
 298 module_exit(gemtek_cleanup);
 299
 300 /*
 301   Local variables:
 302   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"
 303   End:
 304 */