drivers/char/dtlk.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*                                              -*- linux-c -*-
   3  * dtlk.c - DoubleTalk PC driver for Linux
   4  *
   5  * Original author: Chris Pallotta <chris@allmedia.com>
   6  * Current maintainer: Jim Van Zandt <jrv@vanzandt.mv.com>
   7  *
   8  * 2000-03-18 Jim Van Zandt: Fix polling.
   9  *  Eliminate dtlk_timer_active flag and separate dtlk_stop_timer
  10  *  function.  Don't restart timer in dtlk_timer_tick.  Restart timer
  11  *  in dtlk_poll after every poll.  dtlk_poll returns mask (duh).
  12  *  Eliminate unused function dtlk_write_byte.  Misc. code cleanups.
  13  */
  14
  15 /* This driver is for the DoubleTalk PC, a speech synthesizer
  16    manufactured by RC Systems (http://www.rcsys.com/).  It was written
  17    based on documentation in their User's Manual file and Developer's
  18    Tools disk.
  19
  20    The DoubleTalk PC contains four voice synthesizers: text-to-speech
  21    (TTS), linear predictive coding (LPC), PCM/ADPCM, and CVSD.  It
  22    also has a tone generator.  Output data for LPC are written to the
  23    LPC port, and output data for the other modes are written to the
  24    TTS port.
  25
  26    Two kinds of data can be read from the DoubleTalk: status
  27    information (in response to the "\001?" interrogation command) is
  28    read from the TTS port, and index markers (which mark the progress
  29    of the speech) are read from the LPC port.  Not all models of the
  30    DoubleTalk PC implement index markers.  Both the TTS and LPC ports
  31    can also display status flags.
  32
  33    The DoubleTalk PC generates no interrupts.
  34
  35    These characteristics are mapped into the Unix stream I/O model as
  36    follows:
  37
  38    "write" sends bytes to the TTS port.  It is the responsibility of
  39    the user program to switch modes among TTS, PCM/ADPCM, and CVSD.
  40    This driver was written for use with the text-to-speech
  41    synthesizer.  If LPC output is needed some day, other minor device
  42    numbers can be used to select among output modes.
  43
  44    "read" gets index markers from the LPC port.  If the device does
  45    not implement index markers, the read will fail with error EINVAL.
  46
  47    Status information is available using the DTLK_INTERROGATE ioctl.
  48
  49  */
  50
  51 #include <linux/module.h>
  52
  53 #define KERNEL
  54 #include <linux/types.h>
  55 #include <linux/fs.h>
  56 #include <linux/mm.h>
  57 #include <linux/errno.h>        /* for -EBUSY */
  58 #include <linux/ioport.h>       /* for request_region */
  59 #include <linux/delay.h>        /* for loops_per_jiffy */
  60 #include <linux/sched.h>
  61 #include <linux/mutex.h>
  62 #include <asm/io.h>             /* for inb_p, outb_p, inb, outb, etc. */
  63 #include <linux/uaccess.h>      /* for get_user, etc. */
  64 #include <linux/wait.h>         /* for wait_queue */
  65 #include <linux/init.h>         /* for __init, module_{init,exit} */
  66 #include <linux/poll.h>         /* for EPOLLIN, etc. */
  67 #include <linux/dtlk.h>         /* local header file for DoubleTalk values */
  68
  69 #ifdef TRACING
  70 #define TRACE_TEXT(str) printk(str);
  71 #define TRACE_RET printk(")")
  72 #else                           /* !TRACING */
  73 #define TRACE_TEXT(str) ((void) 0)
  74 #define TRACE_RET ((void) 0)
  75 #endif                          /* TRACING */
  76
  77 static DEFINE_MUTEX(dtlk_mutex);
  78 static void dtlk_timer_tick(struct timer_list *unused);
  79
  80 static int dtlk_major;
  81 static int dtlk_port_lpc;
  82 static int dtlk_port_tts;
  83 static int dtlk_busy;
  84 static int dtlk_has_indexing;
  85 static unsigned int dtlk_portlist[] =
  86 {0x25e, 0x29e, 0x2de, 0x31e, 0x35e, 0x39e, 0};
  87 static wait_queue_head_t dtlk_process_list;
  88 static DEFINE_TIMER(dtlk_timer, dtlk_timer_tick);
  89
  90 /* prototypes for file_operations struct */
  91 static ssize_t dtlk_read(struct file *, char __user *,
  92                          size_t nbytes, loff_t * ppos);
  93 static ssize_t dtlk_write(struct file *, const char __user *,
  94                           size_t nbytes, loff_t * ppos);
  95 static __poll_t dtlk_poll(struct file *, poll_table *);
  96 static int dtlk_open(struct inode *, struct file *);
  97 static int dtlk_release(struct inode *, struct file *);
  98 static long dtlk_ioctl(struct file *file,
  99                        unsigned int cmd, unsigned long arg);
 100
 101 static const struct file_operations dtlk_fops =
 102 {
 103         .owner          = THIS_MODULE,
 104         .read           = dtlk_read,
 105         .write          = dtlk_write,
 106         .poll           = dtlk_poll,
 107         .unlocked_ioctl = dtlk_ioctl,
 108         .open           = dtlk_open,
 109         .release        = dtlk_release,
 110 };
 111
 112 /* local prototypes */
 113 static int dtlk_dev_probe(void);
 114 static struct dtlk_settings *dtlk_interrogate(void);
 115 static int dtlk_readable(void);
 116 static char dtlk_read_lpc(void);
 117 static char dtlk_read_tts(void);
 118 static int dtlk_writeable(void);
 119 static char dtlk_write_bytes(const char *buf, int n);
 120 static char dtlk_write_tts(char);
 121 /*
 122    static void dtlk_handle_error(char, char, unsigned int);
 123  */
 124
 125 static ssize_t dtlk_read(struct file *file, char __user *buf,
 126                          size_t count, loff_t * ppos)
 127 {
 128         unsigned int minor = iminor(file_inode(file));
 129         char ch;
 130         int i = 0, retries;
 131
 132         TRACE_TEXT("(dtlk_read");
 133         /*  printk("DoubleTalk PC - dtlk_read()\n"); */
 134
 135         if (minor != DTLK_MINOR || !dtlk_has_indexing)
 136                 return -EINVAL;
 137
 138         for (retries = 0; retries < loops_per_jiffy; retries++) {
 139                 while (i < count && dtlk_readable()) {
 140                         ch = dtlk_read_lpc();
 141                         /*        printk("dtlk_read() reads 0x%02x\n", ch); */
 142                         if (put_user(ch, buf++))
 143                                 return -EFAULT;
 144                         i++;
 145                 }
 146                 if (i)
 147                         return i;
 148                 if (file->f_flags & O_NONBLOCK)
 149                         break;
 150                 msleep_interruptible(100);
 151         }
 152         if (retries == loops_per_jiffy)
 153                 printk(KERN_ERR "dtlk_read times out\n");
 154         TRACE_RET;
 155         return -EAGAIN;
 156 }
 157
 158 static ssize_t dtlk_write(struct file *file, const char __user *buf,
 159                           size_t count, loff_t * ppos)
 160 {
 161         int i = 0, retries = 0, ch;
 162
 163         TRACE_TEXT("(dtlk_write");
 164 #ifdef TRACING
 165         printk(" \"");
 166         {
 167                 int i, ch;
 168                 for (i = 0; i < count; i++) {
 169                         if (get_user(ch, buf + i))
 170                                 return -EFAULT;
 171                         if (' ' <= ch && ch <= '~')
 172                                 printk("%c", ch);
 173                         else
 174                                 printk("\\%03o", ch);
 175                 }
 176                 printk("\"");
 177         }
 178 #endif
 179
 180         if (iminor(file_inode(file)) != DTLK_MINOR)
 181                 return -EINVAL;
 182
 183         while (1) {
 184                 while (i < count && !get_user(ch, buf) &&
 185                        (ch == DTLK_CLEAR || dtlk_writeable())) {
 186                         dtlk_write_tts(ch);
 187                         buf++;
 188                         i++;
 189                         if (i % 5 == 0)
 190                                 /* We yield our time until scheduled
 191                                    again.  This reduces the transfer
 192                                    rate to 500 bytes/sec, but that's
 193                                    still enough to keep up with the
 194                                    speech synthesizer. */
 195                                 msleep_interruptible(1);
 196                         else {
 197                                 /* the RDY bit goes zero 2-3 usec
 198                                    after writing, and goes 1 again
 199                                    180-190 usec later.  Here, we wait
 200                                    up to 250 usec for the RDY bit to
 201                                    go nonzero. */
 202                                 for (retries = 0;
 203                                      retries < loops_per_jiffy / (4000/HZ);
 204                                      retries++)
 205                                         if (inb_p(dtlk_port_tts) &
 206                                             TTS_WRITABLE)
 207                                                 break;
 208                         }
 209                         retries = 0;
 210                 }
 211                 if (i == count)
 212                         return i;
 213                 if (file->f_flags & O_NONBLOCK)
 214                         break;
 215
 216                 msleep_interruptible(1);
 217
 218                 if (++retries > 10 * HZ) { /* wait no more than 10 sec
 219                                               from last write */
 220                         printk("dtlk: write timeout.  "
 221                                "inb_p(dtlk_port_tts) = 0x%02x\n",
 222                                inb_p(dtlk_port_tts));
 223                         TRACE_RET;
 224                         return -EBUSY;
 225                 }
 226         }
 227         TRACE_RET;
 228         return -EAGAIN;
 229 }
 230
 231 static __poll_t dtlk_poll(struct file *file, poll_table * wait)
 232 {
 233         __poll_t mask = 0;
 234         unsigned long expires;
 235
 236         TRACE_TEXT(" dtlk_poll");
 237         /*
 238            static long int j;
 239            printk(".");
 240            printk("<%ld>", jiffies-j);
 241            j=jiffies;
 242          */
 243         poll_wait(file, &dtlk_process_list, wait);
 244
 245         if (dtlk_has_indexing && dtlk_readable()) {
 246                 del_timer(&dtlk_timer);
 247                 mask = EPOLLIN | EPOLLRDNORM;
 248         }
 249         if (dtlk_writeable()) {
 250                 del_timer(&dtlk_timer);
 251                 mask |= EPOLLOUT | EPOLLWRNORM;
 252         }
 253         /* there are no exception conditions */
 254
 255         /* There won't be any interrupts, so we set a timer instead. */
 256         expires = jiffies + 3*HZ / 100;
 257         mod_timer(&dtlk_timer, expires);
 258
 259         return mask;
 260 }
 261
 262 static void dtlk_timer_tick(struct timer_list *unused)
 263 {
 264         TRACE_TEXT(" dtlk_timer_tick");
 265         wake_up_interruptible(&dtlk_process_list);
 266 }
 267
 268 static long dtlk_ioctl(struct file *file,
 269                        unsigned int cmd,
 270                        unsigned long arg)
 271 {
 272         char __user *argp = (char __user *)arg;
 273         struct dtlk_settings *sp;
 274         char portval;
 275         TRACE_TEXT(" dtlk_ioctl");
 276
 277         switch (cmd) {
 278
 279         case DTLK_INTERROGATE:
 280                 mutex_lock(&dtlk_mutex);
 281                 sp = dtlk_interrogate();
 282                 mutex_unlock(&dtlk_mutex);
 283                 if (copy_to_user(argp, sp, sizeof(struct dtlk_settings)))
 284                         return -EINVAL;
 285                 return 0;
 286
 287         case DTLK_STATUS:
 288                 portval = inb_p(dtlk_port_tts);
 289                 return put_user(portval, argp);
 290
 291         default:
 292                 return -EINVAL;
 293         }
 294 }
 295
 296 /* Note that nobody ever sets dtlk_busy... */
 297 static int dtlk_open(struct inode *inode, struct file *file)
 298 {
 299         TRACE_TEXT("(dtlk_open");
 300
 301         switch (iminor(inode)) {
 302         case DTLK_MINOR:
 303                 if (dtlk_busy)
 304                         return -EBUSY;
 305                 return stream_open(inode, file);
 306
 307         default:
 308                 return -ENXIO;
 309         }
 310 }
 311
 312 static int dtlk_release(struct inode *inode, struct file *file)
 313 {
 314         TRACE_TEXT("(dtlk_release");
 315
 316         switch (iminor(inode)) {
 317         case DTLK_MINOR:
 318                 break;
 319
 320         default:
 321                 break;
 322         }
 323         TRACE_RET;
 324
 325         del_timer_sync(&dtlk_timer);
 326
 327         return 0;
 328 }
 329
 330 static int __init dtlk_init(void)
 331 {
 332         int err;
 333
 334         dtlk_port_lpc = 0;
 335         dtlk_port_tts = 0;
 336         dtlk_busy = 0;
 337         dtlk_major = register_chrdev(0, "dtlk", &dtlk_fops);
 338         if (dtlk_major < 0) {
 339                 printk(KERN_ERR "DoubleTalk PC - cannot register device\n");
 340                 return dtlk_major;
 341         }
 342         err = dtlk_dev_probe();
 343         if (err) {
 344                 unregister_chrdev(dtlk_major, "dtlk");
 345                 return err;
 346         }
 347         printk(", MAJOR %d\n", dtlk_major);
 348
 349         init_waitqueue_head(&dtlk_process_list);
 350
 351         return 0;
 352 }
 353
 354 static void __exit dtlk_cleanup (void)
 355 {
 356         dtlk_write_bytes("goodbye", 8);
 357         msleep_interruptible(500);              /* nap 0.50 sec but
 358                                                    could be awakened
 359                                                    earlier by
 360                                                    signals... */
 361
 362         dtlk_write_tts(DTLK_CLEAR);
 363         unregister_chrdev(dtlk_major, "dtlk");
 364         release_region(dtlk_port_lpc, DTLK_IO_EXTENT);
 365 }
 366
 367 module_init(dtlk_init);
 368 module_exit(dtlk_cleanup);
 369
 370 /* ------------------------------------------------------------------------ */
 371
 372 static int dtlk_readable(void)
 373 {
 374 #ifdef TRACING
 375         printk(" dtlk_readable=%u@%u", inb_p(dtlk_port_lpc) != 0x7f, jiffies);
 376 #endif
 377         return inb_p(dtlk_port_lpc) != 0x7f;
 378 }
 379
 380 static int dtlk_writeable(void)
 381 {
 382         /* TRACE_TEXT(" dtlk_writeable"); */
 383 #ifdef TRACINGMORE
 384         printk(" dtlk_writeable=%u", (inb_p(dtlk_port_tts) & TTS_WRITABLE)!=0);
 385 #endif
 386         return inb_p(dtlk_port_tts) & TTS_WRITABLE;
 387 }
 388
 389 static int __init dtlk_dev_probe(void)
 390 {
 391         unsigned int testval = 0;
 392         int i = 0;
 393         struct dtlk_settings *sp;
 394
 395         if (dtlk_port_lpc | dtlk_port_tts)
 396                 return -EBUSY;
 397
 398         for (i = 0; dtlk_portlist[i]; i++) {
 399 #if 0
 400                 printk("DoubleTalk PC - Port %03x = %04x\n",
 401                        dtlk_portlist[i], (testval = inw_p(dtlk_portlist[i])));
 402 #endif
 403
 404                 if (!request_region(dtlk_portlist[i], DTLK_IO_EXTENT,
 405                                "dtlk"))
 406                         continue;
 407                 testval = inw_p(dtlk_portlist[i]);
 408                 if ((testval &= 0xfbff) == 0x107f) {
 409                         dtlk_port_lpc = dtlk_portlist[i];
 410                         dtlk_port_tts = dtlk_port_lpc + 1;
 411
 412                         sp = dtlk_interrogate();
 413                         printk("DoubleTalk PC at %03x-%03x, "
 414                                "ROM version %s, serial number %u",
 415                                dtlk_portlist[i], dtlk_portlist[i] +
 416                                DTLK_IO_EXTENT - 1,
 417                                sp->rom_version, sp->serial_number);
 418
 419                         /* put LPC port into known state, so
 420                            dtlk_readable() gives valid result */
 421                         outb_p(0xff, dtlk_port_lpc);
 422
 423                         /* INIT string and index marker */
 424                         dtlk_write_bytes("\036\1@\0\0012I\r", 8);
 425                         /* posting an index takes 18 msec.  Here, we
 426                            wait up to 100 msec to see whether it
 427                            appears. */
 428                         msleep_interruptible(100);
 429                         dtlk_has_indexing = dtlk_readable();
 430 #ifdef TRACING
 431                         printk(", indexing %d\n", dtlk_has_indexing);
 432 #endif
 433 #ifdef INSCOPE
 434                         {
 435 /* This macro records ten samples read from the LPC port, for later display */
 436 #define LOOK                                    \
 437 for (i = 0; i < 10; i++)                        \
 438   {                                             \
 439     buffer[b++] = inb_p(dtlk_port_lpc);         \
 440     __delay(loops_per_jiffy/(1000000/HZ));             \
 441   }
 442                                 char buffer[1000];
 443                                 int b = 0, i, j;
 444
 445                                 LOOK
 446                                 outb_p(0xff, dtlk_port_lpc);
 447                                 buffer[b++] = 0;
 448                                 LOOK
 449                                 dtlk_write_bytes("\0012I\r", 4);
 450                                 buffer[b++] = 0;
 451                                 __delay(50 * loops_per_jiffy / (1000/HZ));
 452                                 outb_p(0xff, dtlk_port_lpc);
 453                                 buffer[b++] = 0;
 454                                 LOOK
 455
 456                                 printk("\n");
 457                                 for (j = 0; j < b; j++)
 458                                         printk(" %02x", buffer[j]);
 459                                 printk("\n");
 460                         }
 461 #endif                          /* INSCOPE */
 462
 463 #ifdef OUTSCOPE
 464                         {
 465 /* This macro records ten samples read from the TTS port, for later display */
 466 #define LOOK                                    \
 467 for (i = 0; i < 10; i++)                        \
 468   {                                             \
 469     buffer[b++] = inb_p(dtlk_port_tts);         \
 470     __delay(loops_per_jiffy/(1000000/HZ));  /* 1 us */ \
 471   }
 472                                 char buffer[1000];
 473                                 int b = 0, i, j;
 474
 475                                 mdelay(10);     /* 10 ms */
 476                                 LOOK
 477                                 outb_p(0x03, dtlk_port_tts);
 478                                 buffer[b++] = 0;
 479                                 LOOK
 480                                 LOOK
 481
 482                                 printk("\n");
 483                                 for (j = 0; j < b; j++)
 484                                         printk(" %02x", buffer[j]);
 485                                 printk("\n");
 486                         }
 487 #endif                          /* OUTSCOPE */
 488
 489                         dtlk_write_bytes("Double Talk found", 18);
 490
 491                         return 0;
 492                 }
 493                 release_region(dtlk_portlist[i], DTLK_IO_EXTENT);
 494         }
 495
 496         printk(KERN_INFO "DoubleTalk PC - not found\n");
 497         return -ENODEV;
 498 }
 499
 500 /*
 501    static void dtlk_handle_error(char op, char rc, unsigned int minor)
 502    {
 503    printk(KERN_INFO"\nDoubleTalk PC - MINOR: %d, OPCODE: %d, ERROR: %d\n",
 504    minor, op, rc);
 505    return;
 506    }
 507  */
 508
 509 /* interrogate the DoubleTalk PC and return its settings */
 510 static struct dtlk_settings *dtlk_interrogate(void)
 511 {
 512         unsigned char *t;
 513         static char buf[sizeof(struct dtlk_settings) + 1];
 514         int total, i;
 515         static struct dtlk_settings status;
 516         TRACE_TEXT("(dtlk_interrogate");
 517         dtlk_write_bytes("\030\001?", 3);
 518         for (total = 0, i = 0; i < 50; i++) {
 519                 buf[total] = dtlk_read_tts();
 520                 if (total > 2 && buf[total] == 0x7f)
 521                         break;
 522                 if (total < sizeof(struct dtlk_settings))
 523                         total++;
 524         }
 525         /*
 526            if (i==50) printk("interrogate() read overrun\n");
 527            for (i=0; i<sizeof(buf); i++)
 528            printk(" %02x", buf[i]);
 529            printk("\n");
 530          */
 531         t = buf;
 532         status.serial_number = t[0] + t[1] * 256; /* serial number is
 533                                                      little endian */
 534         t += 2;
 535
 536         i = 0;
 537         while (*t != '\r') {
 538                 status.rom_version[i] = *t;
 539                 if (i < sizeof(status.rom_version) - 1)
 540                         i++;
 541                 t++;
 542         }
 543         status.rom_version[i] = 0;
 544         t++;
 545
 546         status.mode = *t++;
 547         status.punc_level = *t++;
 548         status.formant_freq = *t++;
 549         status.pitch = *t++;
 550         status.speed = *t++;
 551         status.volume = *t++;
 552         status.tone = *t++;
 553         status.expression = *t++;
 554         status.ext_dict_loaded = *t++;
 555         status.ext_dict_status = *t++;
 556         status.free_ram = *t++;
 557         status.articulation = *t++;
 558         status.reverb = *t++;
 559         status.eob = *t++;
 560         status.has_indexing = dtlk_has_indexing;
 561         TRACE_RET;
 562         return &status;
 563 }
 564
 565 static char dtlk_read_tts(void)
 566 {
 567         int portval, retries = 0;
 568         char ch;
 569         TRACE_TEXT("(dtlk_read_tts");
 570
 571         /* verify DT is ready, read char, wait for ACK */
 572         do {
 573                 portval = inb_p(dtlk_port_tts);
 574         } while ((portval & TTS_READABLE) == 0 &&
 575                  retries++ < DTLK_MAX_RETRIES);
 576         if (retries > DTLK_MAX_RETRIES)
 577                 printk(KERN_ERR "dtlk_read_tts() timeout\n");
 578
 579         ch = inb_p(dtlk_port_tts);      /* input from TTS port */
 580         ch &= 0x7f;
 581         outb_p(ch, dtlk_port_tts);
 582
 583         retries = 0;
 584         do {
 585                 portval = inb_p(dtlk_port_tts);
 586         } while ((portval & TTS_READABLE) != 0 &&
 587                  retries++ < DTLK_MAX_RETRIES);
 588         if (retries > DTLK_MAX_RETRIES)
 589                 printk(KERN_ERR "dtlk_read_tts() timeout\n");
 590
 591         TRACE_RET;
 592         return ch;
 593 }
 594
 595 static char dtlk_read_lpc(void)
 596 {
 597         int retries = 0;
 598         char ch;
 599         TRACE_TEXT("(dtlk_read_lpc");
 600
 601         /* no need to test -- this is only called when the port is readable */
 602
 603         ch = inb_p(dtlk_port_lpc);      /* input from LPC port */
 604
 605         outb_p(0xff, dtlk_port_lpc);
 606
 607         /* acknowledging a read takes 3-4
 608            usec.  Here, we wait up to 20 usec
 609            for the acknowledgement */
 610         retries = (loops_per_jiffy * 20) / (1000000/HZ);
 611         while (inb_p(dtlk_port_lpc) != 0x7f && --retries > 0);
 612         if (retries == 0)
 613                 printk(KERN_ERR "dtlk_read_lpc() timeout\n");
 614
 615         TRACE_RET;
 616         return ch;
 617 }
 618
 619 /* write n bytes to tts port */
 620 static char dtlk_write_bytes(const char *buf, int n)
 621 {
 622         char val = 0;
 623         /*  printk("dtlk_write_bytes(\"%-*s\", %d)\n", n, buf, n); */
 624         TRACE_TEXT("(dtlk_write_bytes");
 625         while (n-- > 0)
 626                 val = dtlk_write_tts(*buf++);
 627         TRACE_RET;
 628         return val;
 629 }
 630
 631 static char dtlk_write_tts(char ch)
 632 {
 633         int retries = 0;
 634 #ifdef TRACINGMORE
 635         printk("  dtlk_write_tts(");
 636         if (' ' <= ch && ch <= '~')
 637                 printk("'%c'", ch);
 638         else
 639                 printk("0x%02x", ch);
 640 #endif
 641         if (ch != DTLK_CLEAR)   /* no flow control for CLEAR command */
 642                 while ((inb_p(dtlk_port_tts) & TTS_WRITABLE) == 0 &&
 643                        retries++ < DTLK_MAX_RETRIES)    /* DT ready? */
 644                         ;
 645         if (retries > DTLK_MAX_RETRIES)
 646                 printk(KERN_ERR "dtlk_write_tts() timeout\n");
 647
 648         outb_p(ch, dtlk_port_tts);      /* output to TTS port */
 649         /* the RDY bit goes zero 2-3 usec after writing, and goes
 650            1 again 180-190 usec later.  Here, we wait up to 10
 651            usec for the RDY bit to go zero. */
 652         for (retries = 0; retries < loops_per_jiffy / (100000/HZ); retries++)
 653                 if ((inb_p(dtlk_port_tts) & TTS_WRITABLE) == 0)
 654                         break;
 655
 656 #ifdef TRACINGMORE
 657         printk(")\n");
 658 #endif
 659         return 0;
 660 }
 661
 662 MODULE_DESCRIPTION("RC Systems DoubleTalk PC speech card driver");
 663 MODULE_LICENSE("GPL");