drivers/char/radio-aimslab.c

   1 /* radiotrack (radioreveal) driver for Linux radio support
   2  * (c) 1997 M. Kirkwood
   3  * Coverted to new API by Alan Cox <Alan.Cox@linux.org>
   4  * Various bugfixes and enhancements by Russell Kroll <rkroll@exploits.org>
   5  *
   6  * History:
   7  * 1999-02-24   Russell Kroll <rkroll@exploits.org>
   8  *              Fine tuning/VIDEO_TUNER_LOW
   9  *              Frequency range expanded to start at 87 MHz
  10  *
  11  * TODO: Allow for more than one of these foolish entities :-)
  12  *
  13  * Notes on the hardware (reverse engineered from other peoples'
  14  * reverse engineering of AIMS' code :-)
  15  *
  16  *  Frequency control is done digitally -- ie out(port,encodefreq(95.8));
  17  *
  18  *  The signal strength query is unsurprisingly inaccurate.  And it seems
  19  *  to indicate that (on my card, at least) the frequency setting isn't
  20  *  too great.  (I have to tune up .025MHz from what the freq should be
  21  *  to get a report that the thing is tuned.)
  22  *
  23  *  Volume control is (ugh) analogue:
  24  *   out(port, start_increasing_volume);
  25  *   wait(a_wee_while);
  26  *   out(port, stop_changing_the_volume);
  27  *
  28  */
  29
  30 #include <linux/module.h>       /* Modules                      */
  31 #include <linux/init.h>         /* Initdata                     */
  32 #include <linux/ioport.h>       /* check_region, request_region */
  33 #include <linux/delay.h>        /* udelay                       */
  34 #include <asm/io.h>             /* outb, outb_p                 */
  35 #include <asm/uaccess.h>        /* copy to/from user            */
  36 #include <linux/videodev.h>     /* kernel radio structs         */
  37 #include <linux/config.h>       /* CONFIG_RADIO_RTRACK_PORT     */
  38
  39 #ifndef CONFIG_RADIO_RTRACK_PORT
  40 #define CONFIG_RADIO_RTRACK_PORT -1
  41 #endif
  42
  43 static int io = CONFIG_RADIO_RTRACK_PORT;
  44 static int users = 0;
  45
  46 struct rt_device
  47 {
  48         int port;
  49         int curvol;
  50         unsigned long curfreq;
  51         int muted;
  52 };
  53
  54
  55 /* local things */
  56
  57 static void sleep_delay(long n)
  58 {
  59         /* Sleep nicely for 'n' uS */
  60         int d=n/(1000000/HZ);
  61         if(!d)
  62                 udelay(n);
  63         else
  64         {
  65                 /* Yield CPU time */
  66                 unsigned long x=jiffies;
  67                 while((jiffies-x)<=d)
  68                         schedule();
  69         }
  70 }
  71
  72 static void rt_decvol(void)
  73 {
  74         outb(0x58, io);         /* volume down + sigstr + on    */
  75         sleep_delay(100000);
  76         outb(0xd8, io);         /* volume steady + sigstr + on  */
  77 }
  78
  79 static void rt_incvol(void)
  80 {
  81         outb(0x98, io);         /* volume up + sigstr + on      */
  82         sleep_delay(100000);
  83         outb(0xd8, io);         /* volume steady + sigstr + on  */
  84 }
  85
  86 static void rt_mute(struct rt_device *dev)
  87 {
  88         dev->muted = 1;
  89         outb(0xd0, io);                 /* volume steady, off           */
  90 }
  91
  92 static int rt_setvol(struct rt_device *dev, int vol)
  93 {
  94         int i;
  95
  96         if(vol == dev->curvol) {        /* requested volume = current */
  97                 if (dev->muted) {       /* user is unmuting the card  */
  98                         dev->muted = 0;
  99                         outb (0xd8, io);        /* enable card */
 100                 }
 101
 102                 return 0;
 103         }
 104
 105         if(vol == 0) {                  /* volume = 0 means mute the card */
 106                 outb(0x48, io);         /* volume down but still "on"   */
 107                 sleep_delay(2000000);   /* make sure it's totally down  */
 108                 outb(0xd0, io);         /* volume steady, off           */
 109                 dev->curvol = 0;        /* track the volume state!      */
 110                 return 0;
 111         }
 112
 113         dev->muted = 0;
 114         if(vol > dev->curvol)
 115                 for(i = dev->curvol; i < vol; i++)
 116                         rt_incvol();
 117         else
 118                 for(i = dev->curvol; i > vol; i--)
 119                         rt_decvol();
 120
 121         dev->curvol = vol;
 122
 123         return 0;
 124 }
 125
 126 /* the 128+64 on these outb's is to keep the volume stable while tuning
 127  * without them, the volume _will_ creep up with each frequency change
 128  * and bit 4 (+16) is to keep the signal strength meter enabled
 129  */
 130
 131 void send_0_byte(int port, struct rt_device *dev)
 132 {
 133         if ((dev->curvol == 0) || (dev->muted)) {
 134                 outb_p(128+64+16+  1, port);   /* wr-enable + data low */
 135                 outb_p(128+64+16+2+1, port);   /* clock */
 136         }
 137         else {
 138                 outb_p(128+64+16+8+  1, port);  /* on + wr-enable + data low */
 139                 outb_p(128+64+16+8+2+1, port);  /* clock */
 140         }
 141         sleep_delay(1000);
 142 }
 143
 144 void send_1_byte(int port, struct rt_device *dev)
 145 {
 146         if ((dev->curvol == 0) || (dev->muted)) {
 147                 outb_p(128+64+16+4  +1, port);   /* wr-enable+data high */
 148                 outb_p(128+64+16+4+2+1, port);   /* clock */
 149         }
 150         else {
 151                 outb_p(128+64+16+8+4  +1, port); /* on+wr-enable+data high */
 152                 outb_p(128+64+16+8+4+2+1, port); /* clock */
 153         }
 154
 155         sleep_delay(1000);
 156 }
 157
 158 static int rt_setfreq(struct rt_device *dev, unsigned long freq)
 159 {
 160         int i;
 161
 162         /* adapted from radio-aztech.c */
 163
 164         /* now uses VIDEO_TUNER_LOW for fine tuning */
 165
 166         freq += 171200;                 /* Add 10.7 MHz IF              */
 167         freq /= 800;                    /* Convert to 50 kHz units      */
 168
 169         send_0_byte (io, dev);          /*  0: LSB of frequency         */
 170
 171         for (i = 0; i < 13; i++)        /*   : frequency bits (1-13)    */
 172                 if (freq & (1 << i))
 173                         send_1_byte (io, dev);
 174                 else
 175                         send_0_byte (io, dev);
 176
 177         send_0_byte (io, dev);          /* 14: test bit - always 0    */
 178         send_0_byte (io, dev);          /* 15: test bit - always 0    */
 179
 180         send_0_byte (io, dev);          /* 16: band data 0 - always 0 */
 181         send_0_byte (io, dev);          /* 17: band data 1 - always 0 */
 182         send_0_byte (io, dev);          /* 18: band data 2 - always 0 */
 183         send_0_byte (io, dev);          /* 19: time base - always 0   */
 184
 185         send_0_byte (io, dev);          /* 20: spacing (0 = 25 kHz)   */
 186         send_1_byte (io, dev);          /* 21: spacing (1 = 25 kHz)   */
 187         send_0_byte (io, dev);          /* 22: spacing (0 = 25 kHz)   */
 188         send_1_byte (io, dev);          /* 23: AM/FM (FM = 1, always) */
 189
 190         if ((dev->curvol == 0) || (dev->muted))
 191                 outb (0xd0, io);        /* volume steady + sigstr */
 192         else
 193                 outb (0xd8, io);        /* volume steady + sigstr + on */
 194
 195         return 0;
 196 }
 197
 198 int rt_getsigstr(struct rt_device *dev)
 199 {
 200         if (inb(io) & 2)        /* bit set = no signal present  */
 201                 return 0;
 202         return 1;               /* signal present               */
 203 }
 204
 205 static int rt_ioctl(struct video_device *dev, unsigned int cmd, void *arg)
 206 {
 207         struct rt_device *rt=dev->priv;
 208
 209         switch(cmd)
 210         {
 211                 case VIDIOCGCAP:
 212                 {
 213                         struct video_capability v;
 214                         v.type=VID_TYPE_TUNER;
 215                         v.channels=1;
 216                         v.audios=1;
 217                         /* No we don't do pictures */
 218                         v.maxwidth=0;
 219                         v.maxheight=0;
 220                         v.minwidth=0;
 221                         v.minheight=0;
 222                         strcpy(v.name, "RadioTrack");
 223                         if(copy_to_user(arg,&v,sizeof(v)))
 224                                 return -EFAULT;
 225                         return 0;
 226                 }
 227                 case VIDIOCGTUNER:
 228                 {
 229                         struct video_tuner v;
 230                         if(copy_from_user(&v, arg,sizeof(v))!=0)
 231                                 return -EFAULT;
 232                         if(v.tuner)     /* Only 1 tuner */
 233                                 return -EINVAL;
 234                         v.rangelow=(87*16000);
 235                         v.rangehigh=(108*16000);
 236                         v.flags=VIDEO_TUNER_LOW;
 237                         v.mode=VIDEO_MODE_AUTO;
 238                         strcpy(v.name, "FM");
 239                         v.signal=0xFFFF*rt_getsigstr(rt);
 240                         if(copy_to_user(arg,&v, sizeof(v)))
 241                                 return -EFAULT;
 242                         return 0;
 243                 }
 244                 case VIDIOCSTUNER:
 245                 {
 246                         struct video_tuner v;
 247                         if(copy_from_user(&v, arg, sizeof(v)))
 248                                 return -EFAULT;
 249                         if(v.tuner!=0)
 250                                 return -EINVAL;
 251                         /* Only 1 tuner so no setting needed ! */
 252                         return 0;
 253                 }
 254                 case VIDIOCGFREQ:
 255                         if(copy_to_user(arg, &rt->curfreq, sizeof(rt->curfreq)))
 256                                 return -EFAULT;
 257                         return 0;
 258                 case VIDIOCSFREQ:
 259                         if(copy_from_user(&rt->curfreq, arg,sizeof(rt->curfreq)))
 260                                 return -EFAULT;
 261                         rt_setfreq(rt, rt->curfreq);
 262                         return 0;
 263                 case VIDIOCGAUDIO:
 264                 {
 265                         struct video_audio v;
 266                         memset(&v,0, sizeof(v));
 267                         v.flags|=VIDEO_AUDIO_MUTABLE|VIDEO_AUDIO_VOLUME;
 268                         v.volume=rt->curvol * 6554;
 269                         v.step=6554;
 270                         strcpy(v.name, "Radio");
 271                         if(copy_to_user(arg,&v, sizeof(v)))
 272                                 return -EFAULT;
 273                         return 0;
 274                 }
 275                 case VIDIOCSAUDIO:
 276                 {
 277                         struct video_audio v;
 278                         if(copy_from_user(&v, arg, sizeof(v)))
 279                                 return -EFAULT;
 280                         if(v.audio)
 281                                 return -EINVAL;
 282
 283                         if(v.flags&VIDEO_AUDIO_MUTE)
 284                                 rt_mute(rt);
 285                         else
 286                                 rt_setvol(rt,v.volume/6554);
 287
 288                         return 0;
 289                 }
 290                 default:
 291                         return -ENOIOCTLCMD;
 292         }
 293 }
 294
 295 static int rt_open(struct video_device *dev, int flags)
 296 {
 297         if(users)
 298                 return -EBUSY;
 299         users++;
 300         MOD_INC_USE_COUNT;
 301         return 0;
 302 }
 303
 304 static void rt_close(struct video_device *dev)
 305 {
 306         users--;
 307         MOD_DEC_USE_COUNT;
 308 }
 309
 310 static struct rt_device rtrack_unit;
 311
 312 static struct video_device rtrack_radio=
 313 {
 314         "RadioTrack radio",
 315         VID_TYPE_TUNER,
 316         VID_HARDWARE_RTRACK,
 317         rt_open,
 318         rt_close,
 319         NULL,   /* Can't read  (no capture ability) */
 320         NULL,   /* Can't write */
 321         NULL,   /* No poll */
 322         rt_ioctl,
 323         NULL,
 324         NULL
 325 };
 326
 327 __initfunc(int rtrack_init(struct video_init *v))
 328 {
 329         if (check_region(io, 2))
 330         {
 331                 printk(KERN_ERR "rtrack: port 0x%x already in use\n", io);
 332                 return -EBUSY;
 333         }
 334
 335         rtrack_radio.priv=&rtrack_unit;
 336
 337         if(video_register_device(&rtrack_radio, VFL_TYPE_RADIO)==-1)
 338                 return -EINVAL;
 339
 340         request_region(io, 2, "rtrack");
 341         printk(KERN_INFO "AIMSlab Radiotrack/radioreveal card driver.\n");
 342
 343         /* mute card - prevents noisy bootups */
 344
 345         /* this ensures that the volume is all the way down  */
 346         outb(0x48, io);         /* volume down but still "on"   */
 347         sleep_delay(2000000);   /* make sure it's totally down  */
 348         outb(0xc0, io);         /* steady volume, mute card     */
 349         rtrack_unit.curvol = 0;
 350
 351         return 0;
 352 }
 353
 354 #ifdef MODULE
 355
 356 MODULE_AUTHOR("M.Kirkwood");
 357 MODULE_DESCRIPTION("A driver for the RadioTrack/RadioReveal radio card.");
 358 MODULE_PARM(io, "i");
 359 MODULE_PARM_DESC(io, "I/O address of the RadioTrack card (0x20f or 0x30f)");
 360
 361 EXPORT_NO_SYMBOLS;
 362
 363 int init_module(void)
 364 {
 365         if(io==-1)
 366         {
 367                 printk(KERN_ERR "You must set an I/O address with io=0x???\n");
 368                 return -EINVAL;
 369         }
 370         return rtrack_init(NULL);
 371 }
 372
 373 void cleanup_module(void)
 374 {
 375         video_unregister_device(&rtrack_radio);
 376         release_region(io,2);
 377 }
 378
 379 #endif