drivers/media/radio/radio-zoltrix.c

   1 /* zoltrix radio plus driver for Linux radio support
   2  * (c) 1998 C. van Schaik <carl@leg.uct.ac.za>
   3  *
   4  * BUGS
   5  *  Due to the inconsistency in reading from the signal flags
   6  *  it is difficult to get an accurate tuned signal.
   7  *
   8  *  It seems that the card is not linear to 0 volume. It cuts off
   9  *  at a low volume, and it is not possible (at least I have not found)
  10  *  to get fine volume control over the low volume range.
  11  *
  12  *  Some code derived from code by Romolo Manfredini
  13  *                                 romolo@bicnet.it
  14  *
  15  * 1999-05-06 - (C. van Schaik)
  16  *            - Make signal strength and stereo scans
  17  *              kinder to cpu while in delay
  18  * 1999-01-05 - (C. van Schaik)
  19  *            - Changed tuning to 1/160Mhz accuracy
  20  *            - Added stereo support
  21  *              (card defaults to stereo)
  22  *              (can explicitly force mono on the card)
  23  *              (can detect if station is in stereo)
  24  *            - Added unmute function
  25  *            - Reworked ioctl functions
  26  * 2002-07-15 - Fix Stereo typo
  27  */
  28
  29 #include <linux/module.h>       /* Modules                        */
  30 #include <linux/init.h>         /* Initdata                       */
  31 #include <linux/ioport.h>       /* request_region                 */
  32 #include <linux/delay.h>        /* udelay, msleep                 */
  33 #include <asm/io.h>             /* outb, outb_p                   */
  34 #include <asm/uaccess.h>        /* copy to/from user              */
  35 #include <linux/videodev.h>     /* kernel radio structs           */
  36 #include <linux/config.h>       /* CONFIG_RADIO_ZOLTRIX_PORT      */
  37
  38 #ifndef CONFIG_RADIO_ZOLTRIX_PORT
  39 #define CONFIG_RADIO_ZOLTRIX_PORT -1
  40 #endif
  41
  42 static int io = CONFIG_RADIO_ZOLTRIX_PORT;
  43 static int radio_nr = -1;
  44
  45 struct zol_device {
  46         int port;
  47         int curvol;
  48         unsigned long curfreq;
  49         int muted;
  50         unsigned int stereo;
  51         struct semaphore lock;
  52 };
  53
  54 static int zol_setvol(struct zol_device *dev, int vol)
  55 {
  56         dev->curvol = vol;
  57         if (dev->muted)
  58                 return 0;
  59
  60         down(&dev->lock);
  61         if (vol == 0) {
  62                 outb(0, io);
  63                 outb(0, io);
  64                 inb(io + 3);    /* Zoltrix needs to be read to confirm */
  65                 up(&dev->lock);
  66                 return 0;
  67         }
  68
  69         outb(dev->curvol-1, io);
  70         msleep(10);
  71         inb(io + 2);
  72         up(&dev->lock);
  73         return 0;
  74 }
  75
  76 static void zol_mute(struct zol_device *dev)
  77 {
  78         dev->muted = 1;
  79         down(&dev->lock);
  80         outb(0, io);
  81         outb(0, io);
  82         inb(io + 3);            /* Zoltrix needs to be read to confirm */
  83         up(&dev->lock);
  84 }
  85
  86 static void zol_unmute(struct zol_device *dev)
  87 {
  88         dev->muted = 0;
  89         zol_setvol(dev, dev->curvol);
  90 }
  91
  92 static int zol_setfreq(struct zol_device *dev, unsigned long freq)
  93 {
  94         /* tunes the radio to the desired frequency */
  95         unsigned long long bitmask, f, m;
  96         unsigned int stereo = dev->stereo;
  97         int i;
  98
  99         if (freq == 0)
 100                 return 1;
 101         m = (freq / 160 - 8800) * 2;
 102         f = (unsigned long long) m + 0x4d1c;
 103
 104         bitmask = 0xc480402c10080000ull;
 105         i = 45;
 106
 107         down(&dev->lock);
 108
 109         outb(0, io);
 110         outb(0, io);
 111         inb(io + 3);            /* Zoltrix needs to be read to confirm */
 112
 113         outb(0x40, io);
 114         outb(0xc0, io);
 115
 116         bitmask = (bitmask ^ ((f & 0xff) << 47) ^ ((f & 0xff00) << 30) ^ ( stereo << 31));
 117         while (i--) {
 118                 if ((bitmask & 0x8000000000000000ull) != 0) {
 119                         outb(0x80, io);
 120                         udelay(50);
 121                         outb(0x00, io);
 122                         udelay(50);
 123                         outb(0x80, io);
 124                         udelay(50);
 125                 } else {
 126                         outb(0xc0, io);
 127                         udelay(50);
 128                         outb(0x40, io);
 129                         udelay(50);
 130                         outb(0xc0, io);
 131                         udelay(50);
 132                 }
 133                 bitmask *= 2;
 134         }
 135         /* termination sequence */
 136         outb(0x80, io);
 137         outb(0xc0, io);
 138         outb(0x40, io);
 139         udelay(1000);
 140         inb(io+2);
 141
 142         udelay(1000);
 143
 144         if (dev->muted)
 145         {
 146                 outb(0, io);
 147                 outb(0, io);
 148                 inb(io + 3);
 149                 udelay(1000);
 150         }
 151
 152         up(&dev->lock);
 153
 154         if(!dev->muted)
 155         {
 156                 zol_setvol(dev, dev->curvol);
 157         }
 158         return 0;
 159 }
 160
 161 /* Get signal strength */
 162
 163 static int zol_getsigstr(struct zol_device *dev)
 164 {
 165         int a, b;
 166
 167         down(&dev->lock);
 168         outb(0x00, io);         /* This stuff I found to do nothing */
 169         outb(dev->curvol, io);
 170         msleep(20);
 171
 172         a = inb(io);
 173         msleep(10);
 174         b = inb(io);
 175
 176         up(&dev->lock);
 177
 178         if (a != b)
 179                 return (0);
 180
 181         if ((a == 0xcf) || (a == 0xdf)  /* I found this out by playing */
 182                 || (a == 0xef))       /* with a binary scanner on the card io */
 183                 return (1);
 184         return (0);
 185 }
 186
 187 static int zol_is_stereo (struct zol_device *dev)
 188 {
 189         int x1, x2;
 190
 191         down(&dev->lock);
 192
 193         outb(0x00, io);
 194         outb(dev->curvol, io);
 195         msleep(20);
 196
 197         x1 = inb(io);
 198         msleep(10);
 199         x2 = inb(io);
 200
 201         up(&dev->lock);
 202
 203         if ((x1 == x2) && (x1 == 0xcf))
 204                 return 1;
 205         return 0;
 206 }
 207
 208 static int zol_do_ioctl(struct inode *inode, struct file *file,
 209                         unsigned int cmd, void *arg)
 210 {
 211         struct video_device *dev = video_devdata(file);
 212         struct zol_device *zol = dev->priv;
 213
 214         switch (cmd) {
 215         case VIDIOCGCAP:
 216                 {
 217                         struct video_capability *v = arg;
 218
 219                         memset(v,0,sizeof(*v));
 220                         v->type = VID_TYPE_TUNER;
 221                         v->channels = 1 + zol->stereo;
 222                         v->audios = 1;
 223                         strcpy(v->name, "Zoltrix Radio");
 224                         return 0;
 225                 }
 226         case VIDIOCGTUNER:
 227                 {
 228                         struct video_tuner *v = arg;
 229                         if (v->tuner)
 230                                 return -EINVAL;
 231                         strcpy(v->name, "FM");
 232                         v->rangelow = (int) (88.0 * 16000);
 233                         v->rangehigh = (int) (108.0 * 16000);
 234                         v->flags = zol_is_stereo(zol)
 235                                         ? VIDEO_TUNER_STEREO_ON : 0;
 236                         v->flags |= VIDEO_TUNER_LOW;
 237                         v->mode = VIDEO_MODE_AUTO;
 238                         v->signal = 0xFFFF * zol_getsigstr(zol);
 239                         return 0;
 240                 }
 241         case VIDIOCSTUNER:
 242                 {
 243                         struct video_tuner *v = arg;
 244                         if (v->tuner != 0)
 245                                 return -EINVAL;
 246                         /* Only 1 tuner so no setting needed ! */
 247                         return 0;
 248                 }
 249         case VIDIOCGFREQ:
 250         {
 251                 unsigned long *freq = arg;
 252                 *freq = zol->curfreq;
 253                 return 0;
 254         }
 255         case VIDIOCSFREQ:
 256         {
 257                 unsigned long *freq = arg;
 258                 zol->curfreq = *freq;
 259                 zol_setfreq(zol, zol->curfreq);
 260                 return 0;
 261         }
 262         case VIDIOCGAUDIO:
 263                 {
 264                         struct video_audio *v = arg;
 265                         memset(v, 0, sizeof(*v));
 266                         v->flags |= VIDEO_AUDIO_MUTABLE | VIDEO_AUDIO_VOLUME;
 267                         v->mode |= zol_is_stereo(zol)
 268                                 ? VIDEO_SOUND_STEREO : VIDEO_SOUND_MONO;
 269                         v->volume = zol->curvol * 4096;
 270                         v->step = 4096;
 271                         strcpy(v->name, "Zoltrix Radio");
 272                         return 0;
 273                 }
 274         case VIDIOCSAUDIO:
 275                 {
 276                         struct video_audio *v = arg;
 277                         if (v->audio)
 278                                 return -EINVAL;
 279
 280                         if (v->flags & VIDEO_AUDIO_MUTE)
 281                                 zol_mute(zol);
 282                         else {
 283                                 zol_unmute(zol);
 284                                 zol_setvol(zol, v->volume / 4096);
 285                         }
 286
 287                         if (v->mode & VIDEO_SOUND_STEREO) {
 288                                 zol->stereo = 1;
 289                                 zol_setfreq(zol, zol->curfreq);
 290                         }
 291                         if (v->mode & VIDEO_SOUND_MONO) {
 292                                 zol->stereo = 0;
 293                                 zol_setfreq(zol, zol->curfreq);
 294                         }
 295                         return 0;
 296                 }
 297         default:
 298                 return -ENOIOCTLCMD;
 299         }
 300 }
 301
 302 static int zol_ioctl(struct inode *inode, struct file *file,
 303                      unsigned int cmd, unsigned long arg)
 304 {
 305         return video_usercopy(inode, file, cmd, arg, zol_do_ioctl);
 306 }
 307
 308 static struct zol_device zoltrix_unit;
 309
 310 static struct file_operations zoltrix_fops =
 311 {
 312         .owner          = THIS_MODULE,
 313         .open           = video_exclusive_open,
 314         .release        = video_exclusive_release,
 315         .ioctl          = zol_ioctl,
 316         .llseek         = no_llseek,
 317 };
 318
 319 static struct video_device zoltrix_radio =
 320 {
 321         .owner          = THIS_MODULE,
 322         .name           = "Zoltrix Radio Plus",
 323         .type           = VID_TYPE_TUNER,
 324         .hardware       = VID_HARDWARE_ZOLTRIX,
 325         .fops           = &zoltrix_fops,
 326 };
 327
 328 static int __init zoltrix_init(void)
 329 {
 330         if (io == -1) {
 331                 printk(KERN_ERR "You must set an I/O address with io=0x???\n");
 332                 return -EINVAL;
 333         }
 334         if ((io != 0x20c) && (io != 0x30c)) {
 335                 printk(KERN_ERR "zoltrix: invalid port, try 0x20c or 0x30c\n");
 336                 return -ENXIO;
 337         }
 338
 339         zoltrix_radio.priv = &zoltrix_unit;
 340         if (!request_region(io, 2, "zoltrix")) {
 341                 printk(KERN_ERR "zoltrix: port 0x%x already in use\n", io);
 342                 return -EBUSY;
 343         }
 344
 345         if (video_register_device(&zoltrix_radio, VFL_TYPE_RADIO, radio_nr) == -1)
 346         {
 347                 release_region(io, 2);
 348                 return -EINVAL;
 349         }
 350         printk(KERN_INFO "Zoltrix Radio Plus card driver.\n");
 351
 352         init_MUTEX(&zoltrix_unit.lock);
 353
 354         /* mute card - prevents noisy bootups */
 355
 356         /* this ensures that the volume is all the way down  */
 357
 358         outb(0, io);
 359         outb(0, io);
 360         msleep(20);
 361         inb(io + 3);
 362
 363         zoltrix_unit.curvol = 0;
 364         zoltrix_unit.stereo = 1;
 365
 366         return 0;
 367 }
 368
 369 MODULE_AUTHOR("C.van Schaik");
 370 MODULE_DESCRIPTION("A driver for the Zoltrix Radio Plus.");
 371 MODULE_LICENSE("GPL");
 372
 373 module_param(io, int, 0);
 374 MODULE_PARM_DESC(io, "I/O address of the Zoltrix Radio Plus (0x20c or 0x30c)");
 375 module_param(radio_nr, int, 0);
 376
 377 static void __exit zoltrix_cleanup_module(void)
 378 {
 379         video_unregister_device(&zoltrix_radio);
 380         release_region(io, 2);
 381 }
 382
 383 module_init(zoltrix_init);
 384 module_exit(zoltrix_cleanup_module);
 385