drivers/media/radio/radio-miropcm20.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Miro PCM20 radio driver for Linux radio support
   4  * (c) 1998 Ruurd Reitsma <R.A.Reitsma@wbmt.tudelft.nl>
   5  * Thanks to Norberto Pellici for the ACI device interface specification
   6  * The API part is based on the radiotrack driver by M. Kirkwood
   7  * This driver relies on the aci mixer provided by the snd-miro
   8  * ALSA driver.
   9  * Look there for further info...
  10  *
  11  * From the original miro RDS sources:
  12  *
  13  *  (c) 2001 Robert Siemer <Robert.Siemer@gmx.de>
  14  *
  15  *  Many thanks to Fred Seidel <seidel@metabox.de>, the
  16  *  designer of the RDS decoder hardware. With his help
  17  *  I was able to code this driver.
  18  *  Thanks also to Norberto Pellicci, Dominic Mounteney
  19  *  <DMounteney@pinnaclesys.com> and www.teleauskunft.de
  20  *  for good hints on finding Fred. It was somewhat hard
  21  *  to locate him here in Germany... [:
  22  *
  23  * This code has been reintroduced and converted to use
  24  * the new V4L2 RDS API by:
  25  *
  26  * Hans Verkuil <hans.verkuil@cisco.com>
  27  */
  28
  29 #include <linux/module.h>
  30 #include <linux/init.h>
  31 #include <linux/io.h>
  32 #include <linux/delay.h>
  33 #include <linux/videodev2.h>
  34 #include <linux/kthread.h>
  35 #include <media/v4l2-device.h>
  36 #include <media/v4l2-ioctl.h>
  37 #include <media/v4l2-ctrls.h>
  38 #include <media/v4l2-fh.h>
  39 #include <media/v4l2-event.h>
  40 #include <sound/aci.h>
  41
  42 #define RDS_DATASHIFT          2   /* Bit 2 */
  43 #define RDS_DATAMASK        (1 << RDS_DATASHIFT)
  44 #define RDS_BUSYMASK        0x10   /* Bit 4 */
  45 #define RDS_CLOCKMASK       0x08   /* Bit 3 */
  46 #define RDS_DATA(x)         (((x) >> RDS_DATASHIFT) & 1)
  47
  48 #define RDS_STATUS      0x01
  49 #define RDS_STATIONNAME 0x02
  50 #define RDS_TEXT        0x03
  51 #define RDS_ALTFREQ     0x04
  52 #define RDS_TIMEDATE    0x05
  53 #define RDS_PI_CODE     0x06
  54 #define RDS_PTYTATP     0x07
  55 #define RDS_RESET       0x08
  56 #define RDS_RXVALUE     0x09
  57
  58 static int radio_nr = -1;
  59 module_param(radio_nr, int, 0);
  60 MODULE_PARM_DESC(radio_nr, "Set radio device number (/dev/radioX).  Default: -1 (autodetect)");
  61
  62 struct pcm20 {
  63         struct v4l2_device v4l2_dev;
  64         struct video_device vdev;
  65         struct v4l2_ctrl_handler ctrl_handler;
  66         struct v4l2_ctrl *rds_pty;
  67         struct v4l2_ctrl *rds_ps_name;
  68         struct v4l2_ctrl *rds_radio_test;
  69         struct v4l2_ctrl *rds_ta;
  70         struct v4l2_ctrl *rds_tp;
  71         struct v4l2_ctrl *rds_ms;
  72         /* thread for periodic RDS status checking */
  73         struct task_struct *kthread;
  74         unsigned long freq;
  75         u32 audmode;
  76         struct snd_miro_aci *aci;
  77         struct mutex lock;
  78 };
  79
  80 static struct pcm20 pcm20_card = {
  81         .freq = 87 * 16000,
  82         .audmode = V4L2_TUNER_MODE_STEREO,
  83 };
  84
  85
  86 static int rds_waitread(struct snd_miro_aci *aci)
  87 {
  88         u8 byte;
  89         int i = 2000;
  90
  91         do {
  92                 byte = inb(aci->aci_port + ACI_REG_RDS);
  93                 i--;
  94         } while ((byte & RDS_BUSYMASK) && i);
  95
  96         /*
  97          * It's magic, but without this the data that you read later on
  98          * is unreliable and full of bit errors. With this 1 usec delay
  99          * everything is fine.
 100          */
 101         udelay(1);
 102         return i ? byte : -1;
 103 }
 104
 105 static int rds_rawwrite(struct snd_miro_aci *aci, u8 byte)
 106 {
 107         if (rds_waitread(aci) >= 0) {
 108                 outb(byte, aci->aci_port + ACI_REG_RDS);
 109                 return 0;
 110         }
 111         return -1;
 112 }
 113
 114 static int rds_write(struct snd_miro_aci *aci, u8 byte)
 115 {
 116         u8 sendbuffer[8];
 117         int i;
 118
 119         for (i = 7; i >= 0; i--)
 120                 sendbuffer[7 - i] = (byte & (1 << i)) ? RDS_DATAMASK : 0;
 121         sendbuffer[0] |= RDS_CLOCKMASK;
 122
 123         for (i = 0; i < 8; i++)
 124                 rds_rawwrite(aci, sendbuffer[i]);
 125         return 0;
 126 }
 127
 128 static int rds_readcycle_nowait(struct snd_miro_aci *aci)
 129 {
 130         outb(0, aci->aci_port + ACI_REG_RDS);
 131         return rds_waitread(aci);
 132 }
 133
 134 static int rds_readcycle(struct snd_miro_aci *aci)
 135 {
 136         if (rds_rawwrite(aci, 0) < 0)
 137                 return -1;
 138         return rds_waitread(aci);
 139 }
 140
 141 static int rds_ack(struct snd_miro_aci *aci)
 142 {
 143         int i = rds_readcycle(aci);
 144
 145         if (i < 0)
 146                 return -1;
 147         if (i & RDS_DATAMASK)
 148                 return 0;  /* ACK  */
 149         return 1;  /* NACK */
 150 }
 151
 152 static int rds_cmd(struct snd_miro_aci *aci, u8 cmd, u8 databuffer[], u8 datasize)
 153 {
 154         int i, j;
 155
 156         rds_write(aci, cmd);
 157
 158         /* RDS_RESET doesn't need further processing */
 159         if (cmd == RDS_RESET)
 160                 return 0;
 161         if (rds_ack(aci))
 162                 return -EIO;
 163         if (datasize == 0)
 164                 return 0;
 165
 166         /* to be able to use rds_readcycle_nowait()
 167            I have to waitread() here */
 168         if (rds_waitread(aci) < 0)
 169                 return -1;
 170
 171         memset(databuffer, 0, datasize);
 172
 173         for (i = 0; i < 8 * datasize; i++) {
 174                 j = rds_readcycle_nowait(aci);
 175                 if (j < 0)
 176                         return -EIO;
 177                 databuffer[i / 8] |= RDS_DATA(j) << (7 - (i % 8));
 178         }
 179         return 0;
 180 }
 181
 182 static int pcm20_setfreq(struct pcm20 *dev, unsigned long freq)
 183 {
 184         unsigned char freql;
 185         unsigned char freqh;
 186         struct snd_miro_aci *aci = dev->aci;
 187
 188         freq /= 160;
 189         if (!(aci->aci_version == 0x07 || aci->aci_version >= 0xb0))
 190                 freq /= 10;  /* I don't know exactly which version
 191                               * needs this hack */
 192         freql = freq & 0xff;
 193         freqh = freq >> 8;
 194
 195         rds_cmd(aci, RDS_RESET, NULL, 0);
 196         return snd_aci_cmd(aci, ACI_WRITE_TUNE, freql, freqh);
 197 }
 198
 199 static int vidioc_querycap(struct file *file, void *priv,
 200                                 struct v4l2_capability *v)
 201 {
 202         strscpy(v->driver, "Miro PCM20", sizeof(v->driver));
 203         strscpy(v->card, "Miro PCM20", sizeof(v->card));
 204         strscpy(v->bus_info, "ISA:radio-miropcm20", sizeof(v->bus_info));
 205         return 0;
 206 }
 207
 208 static bool sanitize(char *p, int size)
 209 {
 210         int i;
 211         bool ret = true;
 212
 213         for (i = 0; i < size; i++) {
 214                 if (p[i] < 32) {
 215                         p[i] = ' ';
 216                         ret = false;
 217                 }
 218         }
 219         return ret;
 220 }
 221
 222 static int vidioc_g_tuner(struct file *file, void *priv,
 223                                 struct v4l2_tuner *v)
 224 {
 225         struct pcm20 *dev = video_drvdata(file);
 226         int res;
 227         u8 buf;
 228
 229         if (v->index)
 230                 return -EINVAL;
 231         strscpy(v->name, "FM", sizeof(v->name));
 232         v->type = V4L2_TUNER_RADIO;
 233         v->rangelow = 87*16000;
 234         v->rangehigh = 108*16000;
 235         res = snd_aci_cmd(dev->aci, ACI_READ_TUNERSTATION, -1, -1);
 236         v->signal = (res & 0x80) ? 0 : 0xffff;
 237         /* Note: stereo detection does not work if the audio is muted,
 238            it will default to mono in that case. */
 239         res = snd_aci_cmd(dev->aci, ACI_READ_TUNERSTEREO, -1, -1);
 240         v->rxsubchans = (res & 0x40) ? V4L2_TUNER_SUB_MONO :
 241                                         V4L2_TUNER_SUB_STEREO;
 242         v->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO |
 243                         V4L2_TUNER_CAP_RDS | V4L2_TUNER_CAP_RDS_CONTROLS;
 244         v->audmode = dev->audmode;
 245         res = rds_cmd(dev->aci, RDS_RXVALUE, &buf, 1);
 246         if (res >= 0 && buf)
 247                 v->rxsubchans |= V4L2_TUNER_SUB_RDS;
 248         return 0;
 249 }
 250
 251 static int vidioc_s_tuner(struct file *file, void *priv,
 252                                 const struct v4l2_tuner *v)
 253 {
 254         struct pcm20 *dev = video_drvdata(file);
 255
 256         if (v->index)
 257                 return -EINVAL;
 258         if (v->audmode > V4L2_TUNER_MODE_STEREO)
 259                 dev->audmode = V4L2_TUNER_MODE_STEREO;
 260         else
 261                 dev->audmode = v->audmode;
 262         snd_aci_cmd(dev->aci, ACI_SET_TUNERMONO,
 263                         dev->audmode == V4L2_TUNER_MODE_MONO, -1);
 264         return 0;
 265 }
 266
 267 static int vidioc_g_frequency(struct file *file, void *priv,
 268                                 struct v4l2_frequency *f)
 269 {
 270         struct pcm20 *dev = video_drvdata(file);
 271
 272         if (f->tuner != 0)
 273                 return -EINVAL;
 274
 275         f->type = V4L2_TUNER_RADIO;
 276         f->frequency = dev->freq;
 277         return 0;
 278 }
 279
 280
 281 static int vidioc_s_frequency(struct file *file, void *priv,
 282                                 const struct v4l2_frequency *f)
 283 {
 284         struct pcm20 *dev = video_drvdata(file);
 285
 286         if (f->tuner != 0 || f->type != V4L2_TUNER_RADIO)
 287                 return -EINVAL;
 288
 289         dev->freq = clamp_t(u32, f->frequency, 87 * 16000U, 108 * 16000U);
 290         pcm20_setfreq(dev, dev->freq);
 291         return 0;
 292 }
 293
 294 static int pcm20_s_ctrl(struct v4l2_ctrl *ctrl)
 295 {
 296         struct pcm20 *dev = container_of(ctrl->handler, struct pcm20, ctrl_handler);
 297
 298         switch (ctrl->id) {
 299         case V4L2_CID_AUDIO_MUTE:
 300                 snd_aci_cmd(dev->aci, ACI_SET_TUNERMUTE, ctrl->val, -1);
 301                 return 0;
 302         }
 303         return -EINVAL;
 304 }
 305
 306 static int pcm20_thread(void *data)
 307 {
 308         struct pcm20 *dev = data;
 309         const unsigned no_rds_start_counter = 5;
 310         const unsigned sleep_msecs = 2000;
 311         unsigned no_rds_counter = no_rds_start_counter;
 312
 313         for (;;) {
 314                 char text_buffer[66];
 315                 u8 buf;
 316                 int res;
 317
 318                 msleep_interruptible(sleep_msecs);
 319
 320                 if (kthread_should_stop())
 321                         break;
 322
 323                 res = rds_cmd(dev->aci, RDS_RXVALUE, &buf, 1);
 324                 if (res)
 325                         continue;
 326                 if (buf == 0) {
 327                         if (no_rds_counter == 0)
 328                                 continue;
 329                         no_rds_counter--;
 330                         if (no_rds_counter)
 331                                 continue;
 332
 333                         /*
 334                          * No RDS seen for no_rds_start_counter * sleep_msecs
 335                          * milliseconds, clear all RDS controls to their
 336                          * default values.
 337                          */
 338                         v4l2_ctrl_s_ctrl_string(dev->rds_ps_name, "");
 339                         v4l2_ctrl_s_ctrl(dev->rds_ms, 1);
 340                         v4l2_ctrl_s_ctrl(dev->rds_ta, 0);
 341                         v4l2_ctrl_s_ctrl(dev->rds_tp, 0);
 342                         v4l2_ctrl_s_ctrl(dev->rds_pty, 0);
 343                         v4l2_ctrl_s_ctrl_string(dev->rds_radio_test, "");
 344                         continue;
 345                 }
 346                 no_rds_counter = no_rds_start_counter;
 347
 348                 res = rds_cmd(dev->aci, RDS_STATUS, &buf, 1);
 349                 if (res)
 350                         continue;
 351                 if ((buf >> 3) & 1) {
 352                         res = rds_cmd(dev->aci, RDS_STATIONNAME, text_buffer, 8);
 353                         text_buffer[8] = 0;
 354                         if (!res && sanitize(text_buffer, 8))
 355                                 v4l2_ctrl_s_ctrl_string(dev->rds_ps_name, text_buffer);
 356                 }
 357                 if ((buf >> 6) & 1) {
 358                         u8 pty;
 359
 360                         res = rds_cmd(dev->aci, RDS_PTYTATP, &pty, 1);
 361                         if (!res) {
 362                                 v4l2_ctrl_s_ctrl(dev->rds_ms, !!(pty & 0x01));
 363                                 v4l2_ctrl_s_ctrl(dev->rds_ta, !!(pty & 0x02));
 364                                 v4l2_ctrl_s_ctrl(dev->rds_tp, !!(pty & 0x80));
 365                                 v4l2_ctrl_s_ctrl(dev->rds_pty, (pty >> 2) & 0x1f);
 366                         }
 367                 }
 368                 if ((buf >> 4) & 1) {
 369                         res = rds_cmd(dev->aci, RDS_TEXT, text_buffer, 65);
 370                         text_buffer[65] = 0;
 371                         if (!res && sanitize(text_buffer + 1, 64))
 372                                 v4l2_ctrl_s_ctrl_string(dev->rds_radio_test, text_buffer + 1);
 373                 }
 374         }
 375         return 0;
 376 }
 377
 378 static int pcm20_open(struct file *file)
 379 {
 380         struct pcm20 *dev = video_drvdata(file);
 381         int res = v4l2_fh_open(file);
 382
 383         if (!res && v4l2_fh_is_singular_file(file) &&
 384             IS_ERR_OR_NULL(dev->kthread)) {
 385                 dev->kthread = kthread_run(pcm20_thread, dev, "%s",
 386                                            dev->v4l2_dev.name);
 387                 if (IS_ERR(dev->kthread)) {
 388                         v4l2_err(&dev->v4l2_dev, "kernel_thread() failed\n");
 389                         v4l2_fh_release(file);
 390                         return PTR_ERR(dev->kthread);
 391                 }
 392         }
 393         return res;
 394 }
 395
 396 static int pcm20_release(struct file *file)
 397 {
 398         struct pcm20 *dev = video_drvdata(file);
 399
 400         if (v4l2_fh_is_singular_file(file) && !IS_ERR_OR_NULL(dev->kthread)) {
 401                 kthread_stop(dev->kthread);
 402                 dev->kthread = NULL;
 403         }
 404         return v4l2_fh_release(file);
 405 }
 406
 407 static const struct v4l2_file_operations pcm20_fops = {
 408         .owner          = THIS_MODULE,
 409         .open           = pcm20_open,
 410         .poll           = v4l2_ctrl_poll,
 411         .release        = pcm20_release,
 412         .unlocked_ioctl = video_ioctl2,
 413 };
 414
 415 static const struct v4l2_ioctl_ops pcm20_ioctl_ops = {
 416         .vidioc_querycap    = vidioc_querycap,
 417         .vidioc_g_tuner     = vidioc_g_tuner,
 418         .vidioc_s_tuner     = vidioc_s_tuner,
 419         .vidioc_g_frequency = vidioc_g_frequency,
 420         .vidioc_s_frequency = vidioc_s_frequency,
 421         .vidioc_log_status  = v4l2_ctrl_log_status,
 422         .vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
 423         .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
 424 };
 425
 426 static const struct v4l2_ctrl_ops pcm20_ctrl_ops = {
 427         .s_ctrl = pcm20_s_ctrl,
 428 };
 429
 430 static int __init pcm20_init(void)
 431 {
 432         struct pcm20 *dev = &pcm20_card;
 433         struct v4l2_device *v4l2_dev = &dev->v4l2_dev;
 434         struct v4l2_ctrl_handler *hdl;
 435         int res;
 436
 437         dev->aci = snd_aci_get_aci();
 438         if (dev->aci == NULL) {
 439                 v4l2_err(v4l2_dev,
 440                          "you must load the snd-miro driver first!\n");
 441                 return -ENODEV;
 442         }
 443         strscpy(v4l2_dev->name, "radio-miropcm20", sizeof(v4l2_dev->name));
 444         mutex_init(&dev->lock);
 445
 446         res = v4l2_device_register(NULL, v4l2_dev);
 447         if (res < 0) {
 448                 v4l2_err(v4l2_dev, "could not register v4l2_device\n");
 449                 return -EINVAL;
 450         }
 451
 452         hdl = &dev->ctrl_handler;
 453         v4l2_ctrl_handler_init(hdl, 7);
 454         v4l2_ctrl_new_std(hdl, &pcm20_ctrl_ops,
 455                         V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
 456         dev->rds_pty = v4l2_ctrl_new_std(hdl, NULL,
 457                         V4L2_CID_RDS_RX_PTY, 0, 0x1f, 1, 0);
 458         dev->rds_ps_name = v4l2_ctrl_new_std(hdl, NULL,
 459                         V4L2_CID_RDS_RX_PS_NAME, 0, 8, 8, 0);
 460         dev->rds_radio_test = v4l2_ctrl_new_std(hdl, NULL,
 461                         V4L2_CID_RDS_RX_RADIO_TEXT, 0, 64, 64, 0);
 462         dev->rds_ta = v4l2_ctrl_new_std(hdl, NULL,
 463                         V4L2_CID_RDS_RX_TRAFFIC_ANNOUNCEMENT, 0, 1, 1, 0);
 464         dev->rds_tp = v4l2_ctrl_new_std(hdl, NULL,
 465                         V4L2_CID_RDS_RX_TRAFFIC_PROGRAM, 0, 1, 1, 0);
 466         dev->rds_ms = v4l2_ctrl_new_std(hdl, NULL,
 467                         V4L2_CID_RDS_RX_MUSIC_SPEECH, 0, 1, 1, 1);
 468         v4l2_dev->ctrl_handler = hdl;
 469         if (hdl->error) {
 470                 res = hdl->error;
 471                 v4l2_err(v4l2_dev, "Could not register control\n");
 472                 goto err_hdl;
 473         }
 474         strscpy(dev->vdev.name, v4l2_dev->name, sizeof(dev->vdev.name));
 475         dev->vdev.v4l2_dev = v4l2_dev;
 476         dev->vdev.fops = &pcm20_fops;
 477         dev->vdev.ioctl_ops = &pcm20_ioctl_ops;
 478         dev->vdev.release = video_device_release_empty;
 479         dev->vdev.lock = &dev->lock;
 480         dev->vdev.device_caps = V4L2_CAP_TUNER | V4L2_CAP_RADIO |
 481                                 V4L2_CAP_RDS_CAPTURE;
 482         video_set_drvdata(&dev->vdev, dev);
 483         snd_aci_cmd(dev->aci, ACI_SET_TUNERMONO,
 484                         dev->audmode == V4L2_TUNER_MODE_MONO, -1);
 485         pcm20_setfreq(dev, dev->freq);
 486
 487         if (video_register_device(&dev->vdev, VFL_TYPE_RADIO, radio_nr) < 0)
 488                 goto err_hdl;
 489
 490         v4l2_info(v4l2_dev, "Mirosound PCM20 Radio tuner\n");
 491         return 0;
 492 err_hdl:
 493         v4l2_ctrl_handler_free(hdl);
 494         v4l2_device_unregister(v4l2_dev);
 495         return -EINVAL;
 496 }
 497
 498 MODULE_AUTHOR("Ruurd Reitsma, Krzysztof Helt");
 499 MODULE_DESCRIPTION("A driver for the Miro PCM20 radio card.");
 500 MODULE_LICENSE("GPL");
 501
 502 static void __exit pcm20_cleanup(void)
 503 {
 504         struct pcm20 *dev = &pcm20_card;
 505
 506         video_unregister_device(&dev->vdev);
 507         snd_aci_cmd(dev->aci, ACI_SET_TUNERMUTE, 1, -1);
 508         v4l2_ctrl_handler_free(&dev->ctrl_handler);
 509         v4l2_device_unregister(&dev->v4l2_dev);
 510 }
 511
 512 module_init(pcm20_init);
 513 module_exit(pcm20_cleanup);