drivers/media/radio/si470x/radio-si470x-common.c

   1 /*
   2  *  drivers/media/radio/si470x/radio-si470x-common.c
   3  *
   4  *  Driver for radios with Silicon Labs Si470x FM Radio Receivers
   5  *
   6  *  Copyright (c) 2009 Tobias Lorenz <tobias.lorenz@gmx.net>
   7  *  Copyright (c) 2012 Hans de Goede <hdegoede@redhat.com>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  22  */
  23
  24
  25 /*
  26  * History:
  27  * 2008-01-12   Tobias Lorenz <tobias.lorenz@gmx.net>
  28  *              Version 1.0.0
  29  *              - First working version
  30  * 2008-01-13   Tobias Lorenz <tobias.lorenz@gmx.net>
  31  *              Version 1.0.1
  32  *              - Improved error handling, every function now returns errno
  33  *              - Improved multi user access (start/mute/stop)
  34  *              - Channel doesn't get lost anymore after start/mute/stop
  35  *              - RDS support added (polling mode via interrupt EP 1)
  36  *              - marked default module parameters with *value*
  37  *              - switched from bit structs to bit masks
  38  *              - header file cleaned and integrated
  39  * 2008-01-14   Tobias Lorenz <tobias.lorenz@gmx.net>
  40  *              Version 1.0.2
  41  *              - hex values are now lower case
  42  *              - commented USB ID for ADS/Tech moved on todo list
  43  *              - blacklisted si470x in hid-quirks.c
  44  *              - rds buffer handling functions integrated into *_work, *_read
  45  *              - rds_command in si470x_poll exchanged against simple retval
  46  *              - check for firmware version 15
  47  *              - code order and prototypes still remain the same
  48  *              - spacing and bottom of band codes remain the same
  49  * 2008-01-16   Tobias Lorenz <tobias.lorenz@gmx.net>
  50  *              Version 1.0.3
  51  *              - code reordered to avoid function prototypes
  52  *              - switch/case defaults are now more user-friendly
  53  *              - unified comment style
  54  *              - applied all checkpatch.pl v1.12 suggestions
  55  *                except the warning about the too long lines with bit comments
  56  *              - renamed FMRADIO to RADIO to cut line length (checkpatch.pl)
  57  * 2008-01-22   Tobias Lorenz <tobias.lorenz@gmx.net>
  58  *              Version 1.0.4
  59  *              - avoid poss. locking when doing copy_to_user which may sleep
  60  *              - RDS is automatically activated on read now
  61  *              - code cleaned of unnecessary rds_commands
  62  *              - USB Vendor/Product ID for ADS/Tech FM Radio Receiver verified
  63  *                (thanks to Guillaume RAMOUSSE)
  64  * 2008-01-27   Tobias Lorenz <tobias.lorenz@gmx.net>
  65  *              Version 1.0.5
  66  *              - number of seek_retries changed to tune_timeout
  67  *              - fixed problem with incomplete tune operations by own buffers
  68  *              - optimization of variables and printf types
  69  *              - improved error logging
  70  * 2008-01-31   Tobias Lorenz <tobias.lorenz@gmx.net>
  71  *              Oliver Neukum <oliver@neukum.org>
  72  *              Version 1.0.6
  73  *              - fixed coverity checker warnings in *_usb_driver_disconnect
  74  *              - probe()/open() race by correct ordering in probe()
  75  *              - DMA coherency rules by separate allocation of all buffers
  76  *              - use of endianness macros
  77  *              - abuse of spinlock, replaced by mutex
  78  *              - racy handling of timer in disconnect,
  79  *                replaced by delayed_work
  80  *              - racy interruptible_sleep_on(),
  81  *                replaced with wait_event_interruptible()
  82  *              - handle signals in read()
  83  * 2008-02-08   Tobias Lorenz <tobias.lorenz@gmx.net>
  84  *              Oliver Neukum <oliver@neukum.org>
  85  *              Version 1.0.7
  86  *              - usb autosuspend support
  87  *              - unplugging fixed
  88  * 2008-05-07   Tobias Lorenz <tobias.lorenz@gmx.net>
  89  *              Version 1.0.8
  90  *              - hardware frequency seek support
  91  *              - afc indication
  92  *              - more safety checks, let si470x_get_freq return errno
  93  *              - vidioc behavior corrected according to v4l2 spec
  94  * 2008-10-20   Alexey Klimov <klimov.linux@gmail.com>
  95  *              - add support for KWorld USB FM Radio FM700
  96  *              - blacklisted KWorld radio in hid-core.c and hid-ids.h
  97  * 2008-12-03   Mark Lord <mlord@pobox.com>
  98  *              - add support for DealExtreme USB Radio
  99  * 2009-01-31   Bob Ross <pigiron@gmx.com>
 100  *              - correction of stereo detection/setting
 101  *              - correction of signal strength indicator scaling
 102  * 2009-01-31   Rick Bronson <rick@efn.org>
 103  *              Tobias Lorenz <tobias.lorenz@gmx.net>
 104  *              - add LED status output
 105  *              - get HW/SW version from scratchpad
 106  * 2009-06-16   Edouard Lafargue <edouard@lafargue.name>
 107  *              Version 1.0.10
 108  *              - add support for interrupt mode for RDS endpoint,
 109  *                instead of polling.
 110  *                Improves RDS reception significantly
 111  */
 112
 113
 114 /* kernel includes */
 115 #include "radio-si470x.h"
 116
 117
 118
 119 /**************************************************************************
 120  * Module Parameters
 121  **************************************************************************/
 122
 123 /* Spacing (kHz) */
 124 /* 0: 200 kHz (USA, Australia) */
 125 /* 1: 100 kHz (Europe, Japan) */
 126 /* 2:  50 kHz */
 127 static unsigned short space = 2;
 128 module_param(space, ushort, 0444);
 129 MODULE_PARM_DESC(space, "Spacing: 0=200kHz 1=100kHz *2=50kHz*");
 130
 131 /* De-emphasis */
 132 /* 0: 75 us (USA) */
 133 /* 1: 50 us (Europe, Australia, Japan) */
 134 static unsigned short de = 1;
 135 module_param(de, ushort, 0444);
 136 MODULE_PARM_DESC(de, "De-emphasis: 0=75us *1=50us*");
 137
 138 /* Tune timeout */
 139 static unsigned int tune_timeout = 3000;
 140 module_param(tune_timeout, uint, 0644);
 141 MODULE_PARM_DESC(tune_timeout, "Tune timeout: *3000*");
 142
 143 /* Seek timeout */
 144 static unsigned int seek_timeout = 5000;
 145 module_param(seek_timeout, uint, 0644);
 146 MODULE_PARM_DESC(seek_timeout, "Seek timeout: *5000*");
 147
 148 static const struct v4l2_frequency_band bands[] = {
 149         {
 150                 .type = V4L2_TUNER_RADIO,
 151                 .index = 0,
 152                 .capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO |
 153                             V4L2_TUNER_CAP_RDS | V4L2_TUNER_CAP_RDS_BLOCK_IO |
 154                             V4L2_TUNER_CAP_FREQ_BANDS |
 155                             V4L2_TUNER_CAP_HWSEEK_BOUNDED |
 156                             V4L2_TUNER_CAP_HWSEEK_WRAP,
 157                 .rangelow   =  87500 * 16,
 158                 .rangehigh  = 108000 * 16,
 159                 .modulation = V4L2_BAND_MODULATION_FM,
 160         },
 161         {
 162                 .type = V4L2_TUNER_RADIO,
 163                 .index = 1,
 164                 .capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO |
 165                             V4L2_TUNER_CAP_RDS | V4L2_TUNER_CAP_RDS_BLOCK_IO |
 166                             V4L2_TUNER_CAP_FREQ_BANDS |
 167                             V4L2_TUNER_CAP_HWSEEK_BOUNDED |
 168                             V4L2_TUNER_CAP_HWSEEK_WRAP,
 169                 .rangelow   =  76000 * 16,
 170                 .rangehigh  = 108000 * 16,
 171                 .modulation = V4L2_BAND_MODULATION_FM,
 172         },
 173         {
 174                 .type = V4L2_TUNER_RADIO,
 175                 .index = 2,
 176                 .capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO |
 177                             V4L2_TUNER_CAP_RDS | V4L2_TUNER_CAP_RDS_BLOCK_IO |
 178                             V4L2_TUNER_CAP_FREQ_BANDS |
 179                             V4L2_TUNER_CAP_HWSEEK_BOUNDED |
 180                             V4L2_TUNER_CAP_HWSEEK_WRAP,
 181                 .rangelow   =  76000 * 16,
 182                 .rangehigh  =  90000 * 16,
 183                 .modulation = V4L2_BAND_MODULATION_FM,
 184         },
 185 };
 186
 187 /**************************************************************************
 188  * Generic Functions
 189  **************************************************************************/
 190
 191 /*
 192  * si470x_set_band - set the band
 193  */
 194 static int si470x_set_band(struct si470x_device *radio, int band)
 195 {
 196         if (radio->band == band)
 197                 return 0;
 198
 199         radio->band = band;
 200         radio->registers[SYSCONFIG2] &= ~SYSCONFIG2_BAND;
 201         radio->registers[SYSCONFIG2] |= radio->band << 6;
 202         return si470x_set_register(radio, SYSCONFIG2);
 203 }
 204
 205 /*
 206  * si470x_set_chan - set the channel
 207  */
 208 static int si470x_set_chan(struct si470x_device *radio, unsigned short chan)
 209 {
 210         int retval;
 211         bool timed_out = 0;
 212
 213         /* start tuning */
 214         radio->registers[CHANNEL] &= ~CHANNEL_CHAN;
 215         radio->registers[CHANNEL] |= CHANNEL_TUNE | chan;
 216         retval = si470x_set_register(radio, CHANNEL);
 217         if (retval < 0)
 218                 goto done;
 219
 220         /* wait till tune operation has completed */
 221         reinit_completion(&radio->completion);
 222         retval = wait_for_completion_timeout(&radio->completion,
 223                         msecs_to_jiffies(tune_timeout));
 224         if (!retval)
 225                 timed_out = true;
 226
 227         if ((radio->registers[STATUSRSSI] & STATUSRSSI_STC) == 0)
 228                 dev_warn(&radio->videodev.dev, "tune does not complete\n");
 229         if (timed_out)
 230                 dev_warn(&radio->videodev.dev,
 231                         "tune timed out after %u ms\n", tune_timeout);
 232
 233         /* stop tuning */
 234         radio->registers[CHANNEL] &= ~CHANNEL_TUNE;
 235         retval = si470x_set_register(radio, CHANNEL);
 236
 237 done:
 238         return retval;
 239 }
 240
 241 /*
 242  * si470x_get_step - get channel spacing
 243  */
 244 static unsigned int si470x_get_step(struct si470x_device *radio)
 245 {
 246         /* Spacing (kHz) */
 247         switch ((radio->registers[SYSCONFIG2] & SYSCONFIG2_SPACE) >> 4) {
 248         /* 0: 200 kHz (USA, Australia) */
 249         case 0:
 250                 return 200 * 16;
 251         /* 1: 100 kHz (Europe, Japan) */
 252         case 1:
 253                 return 100 * 16;
 254         /* 2:  50 kHz */
 255         default:
 256                 return 50 * 16;
 257         }
 258 }
 259
 260
 261 /*
 262  * si470x_get_freq - get the frequency
 263  */
 264 static int si470x_get_freq(struct si470x_device *radio, unsigned int *freq)
 265 {
 266         int chan, retval;
 267
 268         /* read channel */
 269         retval = si470x_get_register(radio, READCHAN);
 270         chan = radio->registers[READCHAN] & READCHAN_READCHAN;
 271
 272         /* Frequency (MHz) = Spacing (kHz) x Channel + Bottom of Band (MHz) */
 273         *freq = chan * si470x_get_step(radio) + bands[radio->band].rangelow;
 274
 275         return retval;
 276 }
 277
 278
 279 /*
 280  * si470x_set_freq - set the frequency
 281  */
 282 int si470x_set_freq(struct si470x_device *radio, unsigned int freq)
 283 {
 284         unsigned short chan;
 285
 286         freq = clamp(freq, bands[radio->band].rangelow,
 287                            bands[radio->band].rangehigh);
 288         /* Chan = [ Freq (Mhz) - Bottom of Band (MHz) ] / Spacing (kHz) */
 289         chan = (freq - bands[radio->band].rangelow) / si470x_get_step(radio);
 290
 291         return si470x_set_chan(radio, chan);
 292 }
 293
 294
 295 /*
 296  * si470x_set_seek - set seek
 297  */
 298 static int si470x_set_seek(struct si470x_device *radio,
 299                            const struct v4l2_hw_freq_seek *seek)
 300 {
 301         int band, retval;
 302         unsigned int freq;
 303         bool timed_out = 0;
 304
 305         /* set band */
 306         if (seek->rangelow || seek->rangehigh) {
 307                 for (band = 0; band < ARRAY_SIZE(bands); band++) {
 308                         if (bands[band].rangelow  == seek->rangelow &&
 309                             bands[band].rangehigh == seek->rangehigh)
 310                                 break;
 311                 }
 312                 if (band == ARRAY_SIZE(bands))
 313                         return -EINVAL; /* No matching band found */
 314         } else
 315                 band = 1; /* If nothing is specified seek 76 - 108 Mhz */
 316
 317         if (radio->band != band) {
 318                 retval = si470x_get_freq(radio, &freq);
 319                 if (retval)
 320                         return retval;
 321                 retval = si470x_set_band(radio, band);
 322                 if (retval)
 323                         return retval;
 324                 retval = si470x_set_freq(radio, freq);
 325                 if (retval)
 326                         return retval;
 327         }
 328
 329         /* start seeking */
 330         radio->registers[POWERCFG] |= POWERCFG_SEEK;
 331         if (seek->wrap_around)
 332                 radio->registers[POWERCFG] &= ~POWERCFG_SKMODE;
 333         else
 334                 radio->registers[POWERCFG] |= POWERCFG_SKMODE;
 335         if (seek->seek_upward)
 336                 radio->registers[POWERCFG] |= POWERCFG_SEEKUP;
 337         else
 338                 radio->registers[POWERCFG] &= ~POWERCFG_SEEKUP;
 339         retval = si470x_set_register(radio, POWERCFG);
 340         if (retval < 0)
 341                 return retval;
 342
 343         /* wait till tune operation has completed */
 344         reinit_completion(&radio->completion);
 345         retval = wait_for_completion_timeout(&radio->completion,
 346                         msecs_to_jiffies(seek_timeout));
 347         if (!retval)
 348                 timed_out = true;
 349
 350         if ((radio->registers[STATUSRSSI] & STATUSRSSI_STC) == 0)
 351                 dev_warn(&radio->videodev.dev, "seek does not complete\n");
 352         if (radio->registers[STATUSRSSI] & STATUSRSSI_SF)
 353                 dev_warn(&radio->videodev.dev,
 354                         "seek failed / band limit reached\n");
 355
 356         /* stop seeking */
 357         radio->registers[POWERCFG] &= ~POWERCFG_SEEK;
 358         retval = si470x_set_register(radio, POWERCFG);
 359
 360         /* try again, if timed out */
 361         if (retval == 0 && timed_out)
 362                 return -ENODATA;
 363         return retval;
 364 }
 365
 366
 367 /*
 368  * si470x_start - switch on radio
 369  */
 370 int si470x_start(struct si470x_device *radio)
 371 {
 372         int retval;
 373
 374         /* powercfg */
 375         radio->registers[POWERCFG] =
 376                 POWERCFG_DMUTE | POWERCFG_ENABLE | POWERCFG_RDSM;
 377         retval = si470x_set_register(radio, POWERCFG);
 378         if (retval < 0)
 379                 goto done;
 380
 381         /* sysconfig 1 */
 382         radio->registers[SYSCONFIG1] =
 383                 (de << 11) & SYSCONFIG1_DE;             /* DE*/
 384         retval = si470x_set_register(radio, SYSCONFIG1);
 385         if (retval < 0)
 386                 goto done;
 387
 388         /* sysconfig 2 */
 389         radio->registers[SYSCONFIG2] =
 390                 (0x1f  << 8) |                          /* SEEKTH */
 391                 ((radio->band << 6) & SYSCONFIG2_BAND) |/* BAND */
 392                 ((space << 4) & SYSCONFIG2_SPACE) |     /* SPACE */
 393                 15;                                     /* VOLUME (max) */
 394         retval = si470x_set_register(radio, SYSCONFIG2);
 395         if (retval < 0)
 396                 goto done;
 397
 398         /* reset last channel */
 399         retval = si470x_set_chan(radio,
 400                 radio->registers[CHANNEL] & CHANNEL_CHAN);
 401
 402 done:
 403         return retval;
 404 }
 405
 406
 407 /*
 408  * si470x_stop - switch off radio
 409  */
 410 int si470x_stop(struct si470x_device *radio)
 411 {
 412         int retval;
 413
 414         /* sysconfig 1 */
 415         radio->registers[SYSCONFIG1] &= ~SYSCONFIG1_RDS;
 416         retval = si470x_set_register(radio, SYSCONFIG1);
 417         if (retval < 0)
 418                 goto done;
 419
 420         /* powercfg */
 421         radio->registers[POWERCFG] &= ~POWERCFG_DMUTE;
 422         /* POWERCFG_ENABLE has to automatically go low */
 423         radio->registers[POWERCFG] |= POWERCFG_ENABLE | POWERCFG_DISABLE;
 424         retval = si470x_set_register(radio, POWERCFG);
 425
 426 done:
 427         return retval;
 428 }
 429
 430
 431 /*
 432  * si470x_rds_on - switch on rds reception
 433  */
 434 static int si470x_rds_on(struct si470x_device *radio)
 435 {
 436         int retval;
 437
 438         /* sysconfig 1 */
 439         radio->registers[SYSCONFIG1] |= SYSCONFIG1_RDS;
 440         retval = si470x_set_register(radio, SYSCONFIG1);
 441         if (retval < 0)
 442                 radio->registers[SYSCONFIG1] &= ~SYSCONFIG1_RDS;
 443
 444         return retval;
 445 }
 446
 447
 448
 449 /**************************************************************************
 450  * File Operations Interface
 451  **************************************************************************/
 452
 453 /*
 454  * si470x_fops_read - read RDS data
 455  */
 456 static ssize_t si470x_fops_read(struct file *file, char __user *buf,
 457                 size_t count, loff_t *ppos)
 458 {
 459         struct si470x_device *radio = video_drvdata(file);
 460         int retval = 0;
 461         unsigned int block_count = 0;
 462
 463         /* switch on rds reception */
 464         if ((radio->registers[SYSCONFIG1] & SYSCONFIG1_RDS) == 0)
 465                 si470x_rds_on(radio);
 466
 467         /* block if no new data available */
 468         while (radio->wr_index == radio->rd_index) {
 469                 if (file->f_flags & O_NONBLOCK) {
 470                         retval = -EWOULDBLOCK;
 471                         goto done;
 472                 }
 473                 if (wait_event_interruptible(radio->read_queue,
 474                         radio->wr_index != radio->rd_index) < 0) {
 475                         retval = -EINTR;
 476                         goto done;
 477                 }
 478         }
 479
 480         /* calculate block count from byte count */
 481         count /= 3;
 482
 483         /* copy RDS block out of internal buffer and to user buffer */
 484         while (block_count < count) {
 485                 if (radio->rd_index == radio->wr_index)
 486                         break;
 487
 488                 /* always transfer rds complete blocks */
 489                 if (copy_to_user(buf, &radio->buffer[radio->rd_index], 3))
 490                         /* retval = -EFAULT; */
 491                         break;
 492
 493                 /* increment and wrap read pointer */
 494                 radio->rd_index += 3;
 495                 if (radio->rd_index >= radio->buf_size)
 496                         radio->rd_index = 0;
 497
 498                 /* increment counters */
 499                 block_count++;
 500                 buf += 3;
 501                 retval += 3;
 502         }
 503
 504 done:
 505         return retval;
 506 }
 507
 508
 509 /*
 510  * si470x_fops_poll - poll RDS data
 511  */
 512 static unsigned int si470x_fops_poll(struct file *file,
 513                 struct poll_table_struct *pts)
 514 {
 515         struct si470x_device *radio = video_drvdata(file);
 516         unsigned long req_events = poll_requested_events(pts);
 517         int retval = v4l2_ctrl_poll(file, pts);
 518
 519         if (req_events & (POLLIN | POLLRDNORM)) {
 520                 /* switch on rds reception */
 521                 if ((radio->registers[SYSCONFIG1] & SYSCONFIG1_RDS) == 0)
 522                         si470x_rds_on(radio);
 523
 524                 poll_wait(file, &radio->read_queue, pts);
 525
 526                 if (radio->rd_index != radio->wr_index)
 527                         retval |= POLLIN | POLLRDNORM;
 528         }
 529
 530         return retval;
 531 }
 532
 533
 534 /*
 535  * si470x_fops - file operations interface
 536  */
 537 static const struct v4l2_file_operations si470x_fops = {
 538         .owner                  = THIS_MODULE,
 539         .read                   = si470x_fops_read,
 540         .poll                   = si470x_fops_poll,
 541         .unlocked_ioctl         = video_ioctl2,
 542         .open                   = si470x_fops_open,
 543         .release                = si470x_fops_release,
 544 };
 545
 546
 547
 548 /**************************************************************************
 549  * Video4Linux Interface
 550  **************************************************************************/
 551
 552
 553 static int si470x_s_ctrl(struct v4l2_ctrl *ctrl)
 554 {
 555         struct si470x_device *radio =
 556                 container_of(ctrl->handler, struct si470x_device, hdl);
 557
 558         switch (ctrl->id) {
 559         case V4L2_CID_AUDIO_VOLUME:
 560                 radio->registers[SYSCONFIG2] &= ~SYSCONFIG2_VOLUME;
 561                 radio->registers[SYSCONFIG2] |= ctrl->val;
 562                 return si470x_set_register(radio, SYSCONFIG2);
 563         case V4L2_CID_AUDIO_MUTE:
 564                 if (ctrl->val)
 565                         radio->registers[POWERCFG] &= ~POWERCFG_DMUTE;
 566                 else
 567                         radio->registers[POWERCFG] |= POWERCFG_DMUTE;
 568                 return si470x_set_register(radio, POWERCFG);
 569         default:
 570                 return -EINVAL;
 571         }
 572 }
 573
 574
 575 /*
 576  * si470x_vidioc_g_tuner - get tuner attributes
 577  */
 578 static int si470x_vidioc_g_tuner(struct file *file, void *priv,
 579                 struct v4l2_tuner *tuner)
 580 {
 581         struct si470x_device *radio = video_drvdata(file);
 582         int retval = 0;
 583
 584         if (tuner->index != 0)
 585                 return -EINVAL;
 586
 587         if (!radio->status_rssi_auto_update) {
 588                 retval = si470x_get_register(radio, STATUSRSSI);
 589                 if (retval < 0)
 590                         return retval;
 591         }
 592
 593         /* driver constants */
 594         strcpy(tuner->name, "FM");
 595         tuner->type = V4L2_TUNER_RADIO;
 596         tuner->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO |
 597                             V4L2_TUNER_CAP_RDS | V4L2_TUNER_CAP_RDS_BLOCK_IO |
 598                             V4L2_TUNER_CAP_HWSEEK_BOUNDED |
 599                             V4L2_TUNER_CAP_HWSEEK_WRAP;
 600         tuner->rangelow  =  76 * FREQ_MUL;
 601         tuner->rangehigh = 108 * FREQ_MUL;
 602
 603         /* stereo indicator == stereo (instead of mono) */
 604         if ((radio->registers[STATUSRSSI] & STATUSRSSI_ST) == 0)
 605                 tuner->rxsubchans = V4L2_TUNER_SUB_MONO;
 606         else
 607                 tuner->rxsubchans = V4L2_TUNER_SUB_STEREO;
 608         /* If there is a reliable method of detecting an RDS channel,
 609            then this code should check for that before setting this
 610            RDS subchannel. */
 611         tuner->rxsubchans |= V4L2_TUNER_SUB_RDS;
 612
 613         /* mono/stereo selector */
 614         if ((radio->registers[POWERCFG] & POWERCFG_MONO) == 0)
 615                 tuner->audmode = V4L2_TUNER_MODE_STEREO;
 616         else
 617                 tuner->audmode = V4L2_TUNER_MODE_MONO;
 618
 619         /* min is worst, max is best; signal:0..0xffff; rssi: 0..0xff */
 620         /* measured in units of dbµV in 1 db increments (max at ~75 dbµV) */
 621         tuner->signal = (radio->registers[STATUSRSSI] & STATUSRSSI_RSSI);
 622         /* the ideal factor is 0xffff/75 = 873,8 */
 623         tuner->signal = (tuner->signal * 873) + (8 * tuner->signal / 10);
 624         if (tuner->signal > 0xffff)
 625                 tuner->signal = 0xffff;
 626
 627         /* automatic frequency control: -1: freq to low, 1 freq to high */
 628         /* AFCRL does only indicate that freq. differs, not if too low/high */
 629         tuner->afc = (radio->registers[STATUSRSSI] & STATUSRSSI_AFCRL) ? 1 : 0;
 630
 631         return retval;
 632 }
 633
 634
 635 /*
 636  * si470x_vidioc_s_tuner - set tuner attributes
 637  */
 638 static int si470x_vidioc_s_tuner(struct file *file, void *priv,
 639                 const struct v4l2_tuner *tuner)
 640 {
 641         struct si470x_device *radio = video_drvdata(file);
 642
 643         if (tuner->index != 0)
 644                 return -EINVAL;
 645
 646         /* mono/stereo selector */
 647         switch (tuner->audmode) {
 648         case V4L2_TUNER_MODE_MONO:
 649                 radio->registers[POWERCFG] |= POWERCFG_MONO;  /* force mono */
 650                 break;
 651         case V4L2_TUNER_MODE_STEREO:
 652         default:
 653                 radio->registers[POWERCFG] &= ~POWERCFG_MONO; /* try stereo */
 654                 break;
 655         }
 656
 657         return si470x_set_register(radio, POWERCFG);
 658 }
 659
 660
 661 /*
 662  * si470x_vidioc_g_frequency - get tuner or modulator radio frequency
 663  */
 664 static int si470x_vidioc_g_frequency(struct file *file, void *priv,
 665                 struct v4l2_frequency *freq)
 666 {
 667         struct si470x_device *radio = video_drvdata(file);
 668
 669         if (freq->tuner != 0)
 670                 return -EINVAL;
 671
 672         freq->type = V4L2_TUNER_RADIO;
 673         return si470x_get_freq(radio, &freq->frequency);
 674 }
 675
 676
 677 /*
 678  * si470x_vidioc_s_frequency - set tuner or modulator radio frequency
 679  */
 680 static int si470x_vidioc_s_frequency(struct file *file, void *priv,
 681                 const struct v4l2_frequency *freq)
 682 {
 683         struct si470x_device *radio = video_drvdata(file);
 684         int retval;
 685
 686         if (freq->tuner != 0)
 687                 return -EINVAL;
 688
 689         if (freq->frequency < bands[radio->band].rangelow ||
 690             freq->frequency > bands[radio->band].rangehigh) {
 691                 /* Switch to band 1 which covers everything we support */
 692                 retval = si470x_set_band(radio, 1);
 693                 if (retval)
 694                         return retval;
 695         }
 696         return si470x_set_freq(radio, freq->frequency);
 697 }
 698
 699
 700 /*
 701  * si470x_vidioc_s_hw_freq_seek - set hardware frequency seek
 702  */
 703 static int si470x_vidioc_s_hw_freq_seek(struct file *file, void *priv,
 704                 const struct v4l2_hw_freq_seek *seek)
 705 {
 706         struct si470x_device *radio = video_drvdata(file);
 707
 708         if (seek->tuner != 0)
 709                 return -EINVAL;
 710
 711         if (file->f_flags & O_NONBLOCK)
 712                 return -EWOULDBLOCK;
 713
 714         return si470x_set_seek(radio, seek);
 715 }
 716
 717 /*
 718  * si470x_vidioc_enum_freq_bands - enumerate supported bands
 719  */
 720 static int si470x_vidioc_enum_freq_bands(struct file *file, void *priv,
 721                                          struct v4l2_frequency_band *band)
 722 {
 723         if (band->tuner != 0)
 724                 return -EINVAL;
 725         if (band->index >= ARRAY_SIZE(bands))
 726                 return -EINVAL;
 727         *band = bands[band->index];
 728         return 0;
 729 }
 730
 731 const struct v4l2_ctrl_ops si470x_ctrl_ops = {
 732         .s_ctrl = si470x_s_ctrl,
 733 };
 734
 735 /*
 736  * si470x_ioctl_ops - video device ioctl operations
 737  */
 738 static const struct v4l2_ioctl_ops si470x_ioctl_ops = {
 739         .vidioc_querycap        = si470x_vidioc_querycap,
 740         .vidioc_g_tuner         = si470x_vidioc_g_tuner,
 741         .vidioc_s_tuner         = si470x_vidioc_s_tuner,
 742         .vidioc_g_frequency     = si470x_vidioc_g_frequency,
 743         .vidioc_s_frequency     = si470x_vidioc_s_frequency,
 744         .vidioc_s_hw_freq_seek  = si470x_vidioc_s_hw_freq_seek,
 745         .vidioc_enum_freq_bands = si470x_vidioc_enum_freq_bands,
 746         .vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
 747         .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
 748 };
 749
 750
 751 /*
 752  * si470x_viddev_template - video device interface
 753  */
 754 struct video_device si470x_viddev_template = {
 755         .fops                   = &si470x_fops,
 756         .name                   = DRIVER_NAME,
 757         .release                = video_device_release_empty,
 758         .ioctl_ops              = &si470x_ioctl_ops,
 759 };