drivers/media/radio/radio-typhoon.c

   1 /* Typhoon Radio Card driver for radio support
   2  * (c) 1999 Dr. Henrik Seidel <Henrik.Seidel@gmx.de>
   3  *
   4  * Card manufacturer:
   5  * http://194.18.155.92/idc/prod2.idc?nr=50753&lang=e
   6  *
   7  * Notes on the hardware
   8  *
   9  * This card has two output sockets, one for speakers and one for line.
  10  * The speaker output has volume control, but only in four discrete
  11  * steps. The line output has neither volume control nor mute.
  12  *
  13  * The card has auto-stereo according to its manual, although it all
  14  * sounds mono to me (even with the Win/DOS drivers). Maybe it's my
  15  * antenna - I really don't know for sure.
  16  *
  17  * Frequency control is done digitally.
  18  *
  19  * Volume control is done digitally, but there are only four different
  20  * possible values. So you should better always turn the volume up and
  21  * use line control. I got the best results by connecting line output
  22  * to the sound card microphone input. For such a configuration the
  23  * volume control has no effect, since volume control only influences
  24  * the speaker output.
  25  *
  26  * There is no explicit mute/unmute. So I set the radio frequency to a
  27  * value where I do expect just noise and turn the speaker volume down.
  28  * The frequency change is necessary since the card never seems to be
  29  * completely silent.
  30  */
  31
  32 #include <linux/module.h>       /* Modules                        */
  33 #include <linux/init.h>         /* Initdata                       */
  34 #include <linux/ioport.h>       /* request_region                 */
  35 #include <linux/proc_fs.h>      /* radio card status report       */
  36 #include <asm/io.h>             /* outb, outb_p                   */
  37 #include <asm/uaccess.h>        /* copy to/from user              */
  38 #include <linux/videodev.h>     /* kernel radio structs           */
  39 #include <linux/config.h>       /* CONFIG_RADIO_TYPHOON_*         */
  40
  41 #define BANNER "Typhoon Radio Card driver v0.1\n"
  42
  43 #ifndef CONFIG_RADIO_TYPHOON_PORT
  44 #define CONFIG_RADIO_TYPHOON_PORT -1
  45 #endif
  46
  47 #ifndef CONFIG_RADIO_TYPHOON_MUTEFREQ
  48 #define CONFIG_RADIO_TYPHOON_MUTEFREQ 0
  49 #endif
  50
  51 #ifndef CONFIG_PROC_FS
  52 #undef CONFIG_RADIO_TYPHOON_PROC_FS
  53 #endif
  54
  55 struct typhoon_device {
  56         int users;
  57         int iobase;
  58         int curvol;
  59         int muted;
  60         unsigned long curfreq;
  61         unsigned long mutefreq;
  62         struct mutex lock;
  63 };
  64
  65 static void typhoon_setvol_generic(struct typhoon_device *dev, int vol);
  66 static int typhoon_setfreq_generic(struct typhoon_device *dev,
  67                                    unsigned long frequency);
  68 static int typhoon_setfreq(struct typhoon_device *dev, unsigned long frequency);
  69 static void typhoon_mute(struct typhoon_device *dev);
  70 static void typhoon_unmute(struct typhoon_device *dev);
  71 static int typhoon_setvol(struct typhoon_device *dev, int vol);
  72 static int typhoon_ioctl(struct inode *inode, struct file *file,
  73                          unsigned int cmd, unsigned long arg);
  74 #ifdef CONFIG_RADIO_TYPHOON_PROC_FS
  75 static int typhoon_get_info(char *buf, char **start, off_t offset, int len);
  76 #endif
  77
  78 static void typhoon_setvol_generic(struct typhoon_device *dev, int vol)
  79 {
  80         mutex_lock(&dev->lock);
  81         vol >>= 14;                             /* Map 16 bit to 2 bit */
  82         vol &= 3;
  83         outb_p(vol / 2, dev->iobase);           /* Set the volume, high bit. */
  84         outb_p(vol % 2, dev->iobase + 2);       /* Set the volume, low bit. */
  85         mutex_unlock(&dev->lock);
  86 }
  87
  88 static int typhoon_setfreq_generic(struct typhoon_device *dev,
  89                                    unsigned long frequency)
  90 {
  91         unsigned long outval;
  92         unsigned long x;
  93
  94         /*
  95          * The frequency transfer curve is not linear. The best fit I could
  96          * get is
  97          *
  98          * outval = -155 + exp((f + 15.55) * 0.057))
  99          *
 100          * where frequency f is in MHz. Since we don't have exp in the kernel,
 101          * I approximate this function by a third order polynomial.
 102          *
 103          */
 104
 105         mutex_lock(&dev->lock);
 106         x = frequency / 160;
 107         outval = (x * x + 2500) / 5000;
 108         outval = (outval * x + 5000) / 10000;
 109         outval -= (10 * x * x + 10433) / 20866;
 110         outval += 4 * x - 11505;
 111
 112         outb_p((outval >> 8) & 0x01, dev->iobase + 4);
 113         outb_p(outval >> 9, dev->iobase + 6);
 114         outb_p(outval & 0xff, dev->iobase + 8);
 115         mutex_unlock(&dev->lock);
 116
 117         return 0;
 118 }
 119
 120 static int typhoon_setfreq(struct typhoon_device *dev, unsigned long frequency)
 121 {
 122         typhoon_setfreq_generic(dev, frequency);
 123         dev->curfreq = frequency;
 124         return 0;
 125 }
 126
 127 static void typhoon_mute(struct typhoon_device *dev)
 128 {
 129         if (dev->muted == 1)
 130                 return;
 131         typhoon_setvol_generic(dev, 0);
 132         typhoon_setfreq_generic(dev, dev->mutefreq);
 133         dev->muted = 1;
 134 }
 135
 136 static void typhoon_unmute(struct typhoon_device *dev)
 137 {
 138         if (dev->muted == 0)
 139                 return;
 140         typhoon_setfreq_generic(dev, dev->curfreq);
 141         typhoon_setvol_generic(dev, dev->curvol);
 142         dev->muted = 0;
 143 }
 144
 145 static int typhoon_setvol(struct typhoon_device *dev, int vol)
 146 {
 147         if (dev->muted && vol != 0) {   /* user is unmuting the card */
 148                 dev->curvol = vol;
 149                 typhoon_unmute(dev);
 150                 return 0;
 151         }
 152         if (vol == dev->curvol)         /* requested volume == current */
 153                 return 0;
 154
 155         if (vol == 0) {                 /* volume == 0 means mute the card */
 156                 typhoon_mute(dev);
 157                 dev->curvol = vol;
 158                 return 0;
 159         }
 160         typhoon_setvol_generic(dev, vol);
 161         dev->curvol = vol;
 162         return 0;
 163 }
 164
 165
 166 static int typhoon_do_ioctl(struct inode *inode, struct file *file,
 167                             unsigned int cmd, void *arg)
 168 {
 169         struct video_device *dev = video_devdata(file);
 170         struct typhoon_device *typhoon = dev->priv;
 171
 172         switch (cmd) {
 173         case VIDIOCGCAP:
 174                 {
 175                         struct video_capability *v = arg;
 176                         memset(v,0,sizeof(*v));
 177                         v->type = VID_TYPE_TUNER;
 178                         v->channels = 1;
 179                         v->audios = 1;
 180                         strcpy(v->name, "Typhoon Radio");
 181                         return 0;
 182                 }
 183         case VIDIOCGTUNER:
 184                 {
 185                         struct video_tuner *v = arg;
 186                         if (v->tuner)   /* Only 1 tuner */
 187                                 return -EINVAL;
 188                         v->rangelow = 875 * 1600;
 189                         v->rangehigh = 1080 * 1600;
 190                         v->flags = VIDEO_TUNER_LOW;
 191                         v->mode = VIDEO_MODE_AUTO;
 192                         v->signal = 0xFFFF;     /* We can't get the signal strength */
 193                         strcpy(v->name, "FM");
 194                         return 0;
 195                 }
 196         case VIDIOCSTUNER:
 197                 {
 198                         struct video_tuner *v = arg;
 199                         if (v->tuner != 0)
 200                                 return -EINVAL;
 201                         /* Only 1 tuner so no setting needed ! */
 202                         return 0;
 203                 }
 204         case VIDIOCGFREQ:
 205         {
 206                 unsigned long *freq = arg;
 207                 *freq = typhoon->curfreq;
 208                 return 0;
 209         }
 210         case VIDIOCSFREQ:
 211         {
 212                 unsigned long *freq = arg;
 213                 typhoon->curfreq = *freq;
 214                 typhoon_setfreq(typhoon, typhoon->curfreq);
 215                 return 0;
 216         }
 217         case VIDIOCGAUDIO:
 218                 {
 219                         struct video_audio *v = arg;
 220                         memset(v, 0, sizeof(*v));
 221                         v->flags |= VIDEO_AUDIO_MUTABLE | VIDEO_AUDIO_VOLUME;
 222                         v->mode |= VIDEO_SOUND_MONO;
 223                         v->volume = typhoon->curvol;
 224                         v->step = 1 << 14;
 225                         strcpy(v->name, "Typhoon Radio");
 226                         return 0;
 227                 }
 228         case VIDIOCSAUDIO:
 229                 {
 230                         struct video_audio *v = arg;
 231                         if (v->audio)
 232                                 return -EINVAL;
 233                         if (v->flags & VIDEO_AUDIO_MUTE)
 234                                 typhoon_mute(typhoon);
 235                         else
 236                                 typhoon_unmute(typhoon);
 237                         if (v->flags & VIDEO_AUDIO_VOLUME)
 238                                 typhoon_setvol(typhoon, v->volume);
 239                         return 0;
 240                 }
 241         default:
 242                 return -ENOIOCTLCMD;
 243         }
 244 }
 245
 246 static int typhoon_ioctl(struct inode *inode, struct file *file,
 247                          unsigned int cmd, unsigned long arg)
 248 {
 249         return video_usercopy(inode, file, cmd, arg, typhoon_do_ioctl);
 250 }
 251
 252 static struct typhoon_device typhoon_unit =
 253 {
 254         .iobase         = CONFIG_RADIO_TYPHOON_PORT,
 255         .curfreq        = CONFIG_RADIO_TYPHOON_MUTEFREQ,
 256         .mutefreq       = CONFIG_RADIO_TYPHOON_MUTEFREQ,
 257 };
 258
 259 static struct file_operations typhoon_fops = {
 260         .owner          = THIS_MODULE,
 261         .open           = video_exclusive_open,
 262         .release        = video_exclusive_release,
 263         .ioctl          = typhoon_ioctl,
 264         .compat_ioctl   = v4l_compat_ioctl32,
 265         .llseek         = no_llseek,
 266 };
 267
 268 static struct video_device typhoon_radio =
 269 {
 270         .owner          = THIS_MODULE,
 271         .name           = "Typhoon Radio",
 272         .type           = VID_TYPE_TUNER,
 273         .hardware       = VID_HARDWARE_TYPHOON,
 274         .fops           = &typhoon_fops,
 275 };
 276
 277 #ifdef CONFIG_RADIO_TYPHOON_PROC_FS
 278
 279 static int typhoon_get_info(char *buf, char **start, off_t offset, int len)
 280 {
 281         char *out = buf;
 282
 283         #ifdef MODULE
 284             #define MODULEPROCSTRING "Driver loaded as a module"
 285         #else
 286             #define MODULEPROCSTRING "Driver compiled into kernel"
 287         #endif
 288
 289         /* output must be kept under PAGE_SIZE */
 290         out += sprintf(out, BANNER);
 291         out += sprintf(out, "Load type: " MODULEPROCSTRING "\n\n");
 292         out += sprintf(out, "frequency = %lu kHz\n",
 293                 typhoon_unit.curfreq >> 4);
 294         out += sprintf(out, "volume = %d\n", typhoon_unit.curvol);
 295         out += sprintf(out, "mute = %s\n", typhoon_unit.muted ?
 296                 "on" : "off");
 297         out += sprintf(out, "iobase = 0x%x\n", typhoon_unit.iobase);
 298         out += sprintf(out, "mute frequency = %lu kHz\n",
 299                 typhoon_unit.mutefreq >> 4);
 300         return out - buf;
 301 }
 302
 303 #endif /* CONFIG_RADIO_TYPHOON_PROC_FS */
 304
 305 MODULE_AUTHOR("Dr. Henrik Seidel");
 306 MODULE_DESCRIPTION("A driver for the Typhoon radio card (a.k.a. EcoRadio).");
 307 MODULE_LICENSE("GPL");
 308
 309 static int io = -1;
 310 static int radio_nr = -1;
 311
 312 module_param(io, int, 0);
 313 MODULE_PARM_DESC(io, "I/O address of the Typhoon card (0x316 or 0x336)");
 314 module_param(radio_nr, int, 0);
 315
 316 #ifdef MODULE
 317 static unsigned long mutefreq = 0;
 318 module_param(mutefreq, ulong, 0);
 319 MODULE_PARM_DESC(mutefreq, "Frequency used when muting the card (in kHz)");
 320 #endif
 321
 322 static int __init typhoon_init(void)
 323 {
 324 #ifdef MODULE
 325         if (io == -1) {
 326                 printk(KERN_ERR "radio-typhoon: You must set an I/O address with io=0x316 or io=0x336\n");
 327                 return -EINVAL;
 328         }
 329         typhoon_unit.iobase = io;
 330
 331         if (mutefreq < 87000 || mutefreq > 108500) {
 332                 printk(KERN_ERR "radio-typhoon: You must set a frequency (in kHz) used when muting the card,\n");
 333                 printk(KERN_ERR "radio-typhoon: e.g. with \"mutefreq=87500\" (87000 <= mutefreq <= 108500)\n");
 334                 return -EINVAL;
 335         }
 336         typhoon_unit.mutefreq = mutefreq;
 337 #endif /* MODULE */
 338
 339         printk(KERN_INFO BANNER);
 340         mutex_init(&typhoon_unit.lock);
 341         io = typhoon_unit.iobase;
 342         if (!request_region(io, 8, "typhoon")) {
 343                 printk(KERN_ERR "radio-typhoon: port 0x%x already in use\n",
 344                        typhoon_unit.iobase);
 345                 return -EBUSY;
 346         }
 347
 348         typhoon_radio.priv = &typhoon_unit;
 349         if (video_register_device(&typhoon_radio, VFL_TYPE_RADIO, radio_nr) == -1)
 350         {
 351                 release_region(io, 8);
 352                 return -EINVAL;
 353         }
 354         printk(KERN_INFO "radio-typhoon: port 0x%x.\n", typhoon_unit.iobase);
 355         printk(KERN_INFO "radio-typhoon: mute frequency is %lu kHz.\n",
 356                typhoon_unit.mutefreq);
 357         typhoon_unit.mutefreq <<= 4;
 358
 359         /* mute card - prevents noisy bootups */
 360         typhoon_mute(&typhoon_unit);
 361
 362 #ifdef CONFIG_RADIO_TYPHOON_PROC_FS
 363         if (!create_proc_info_entry("driver/radio-typhoon", 0, NULL,
 364                                     typhoon_get_info))
 365                 printk(KERN_ERR "radio-typhoon: registering /proc/driver/radio-typhoon failed\n");
 366 #endif
 367
 368         return 0;
 369 }
 370
 371 static void __exit typhoon_cleanup_module(void)
 372 {
 373
 374 #ifdef CONFIG_RADIO_TYPHOON_PROC_FS
 375         remove_proc_entry("driver/radio-typhoon", NULL);
 376 #endif
 377
 378         video_unregister_device(&typhoon_radio);
 379         release_region(io, 8);
 380 }
 381
 382 module_init(typhoon_init);
 383 module_exit(typhoon_cleanup_module);
 384