sys/dev/usbmisc/ucom/ucom.c

   1 /*
   2  * $NetBSD: ucom.c,v 1.39 2001/08/16 22:31:24 augustss Exp $
   3  * $NetBSD: ucom.c,v 1.40 2001/11/13 06:24:54 lukem Exp $
   4  * $FreeBSD: src/sys/dev/usb/ucom.c,v 1.35 2003/11/16 11:58:21 akiyama Exp $
   5  * $DragonFly: src/sys/dev/usbmisc/ucom/ucom.c,v 1.17 2004/10/16 03:20:52 dillon Exp $
   6  */
   7 /*-
   8  * Copyright (c) 2001-2002, Shunsuke Akiyama <akiyama@jp.FreeBSD.org>.
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  */
  32
  33 /*
  34  * Copyright (c) 1998, 2000 The NetBSD Foundation, Inc.
  35  * All rights reserved.
  36  *
  37  * This code is derived from software contributed to The NetBSD Foundation
  38  * by Lennart Augustsson (lennart@augustsson.net) at
  39  * Carlstedt Research & Technology.
  40  *
  41  * Redistribution and use in source and binary forms, with or without
  42  * modification, are permitted provided that the following conditions
  43  * are met:
  44  * 1. Redistributions of source code must retain the above copyright
  45  *    notice, this list of conditions and the following disclaimer.
  46  * 2. Redistributions in binary form must reproduce the above copyright
  47  *    notice, this list of conditions and the following disclaimer in the
  48  *    documentation and/or other materials provided with the distribution.
  49  * 3. All advertising materials mentioning features or use of this software
  50  *    must display the following acknowledgement:
  51  *        This product includes software developed by the NetBSD
  52  *        Foundation, Inc. and its contributors.
  53  * 4. Neither the name of The NetBSD Foundation nor the names of its
  54  *    contributors may be used to endorse or promote products derived
  55  *    from this software without specific prior written permission.
  56  *
  57  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  58  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  59  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  60  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  61  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  62  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  63  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  64  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  65  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  66  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  67  * POSSIBILITY OF SUCH DAMAGE.
  68  */
  69
  70 #include <sys/param.h>
  71 #include <sys/systm.h>
  72 #include <sys/kernel.h>
  73 #include <sys/malloc.h>
  74 #include <sys/bus.h>
  75 #include <sys/ioccom.h>
  76 #include <sys/fcntl.h>
  77 #include <sys/conf.h>
  78 #include <sys/tty.h>
  79 #include <sys/clist.h>
  80 #include <sys/file.h>
  81 #if defined(__FreeBSD__) && __FreeBSD_version >= 500014
  82 #include <sys/selinfo.h>
  83 #else
  84 #include <sys/select.h>
  85 #endif
  86 #include <sys/proc.h>
  87 #include <sys/vnode.h>
  88 #include <sys/poll.h>
  89 #include <sys/sysctl.h>
  90
  91 #include <bus/usb/usb.h>
  92 #include <bus/usb/usbcdc.h>
  93
  94 #include <bus/usb/usbdi.h>
  95 #include <bus/usb/usbdi_util.h>
  96 #include <bus/usb/usbdevs.h>
  97 #include <bus/usb/usb_quirks.h>
  98
  99 #include "ucomvar.h"
 100
 101 #ifdef USB_DEBUG
 102 static int      ucomdebug = 0;
 103 SYSCTL_NODE(_hw_usb, OID_AUTO, ucom, CTLFLAG_RW, 0, "USB ucom");
 104 SYSCTL_INT(_hw_usb_ucom, OID_AUTO, debug, CTLFLAG_RW,
 105            &ucomdebug, 0, "ucom debug level");
 106 #define DPRINTF(x)      do { \
 107                                 if (ucomdebug) \
 108                                         logprintf x; \
 109                         } while (0)
 110
 111 #define DPRINTFN(n, x)  do { \
 112                                 if (ucomdebug > (n)) \
 113                                         logprintf x; \
 114                         } while (0)
 115 #else
 116 #define DPRINTF(x)
 117 #define DPRINTFN(n, x)
 118 #endif
 119
 120 Static d_open_t  ucomopen;
 121 Static d_close_t ucomclose;
 122 Static d_read_t  ucomread;
 123 Static d_write_t ucomwrite;
 124 Static d_ioctl_t ucomioctl;
 125
 126 #define UCOM_CDEV_MAJOR  138
 127
 128 static struct cdevsw ucom_cdevsw = {
 129         /* name */      "ucom",
 130         /* maj */       UCOM_CDEV_MAJOR,
 131         /* flags */     D_TTY | D_KQFILTER,
 132         /* port */      NULL,
 133         /* clone */     NULL,
 134
 135         /* open */      ucomopen,
 136         /* close */     ucomclose,
 137         /* read */      ucomread,
 138         /* write */     ucomwrite,
 139         /* ioctl */     ucomioctl,
 140         /* poll */      ttypoll,
 141         /* mmap */      nommap,
 142         /* strategy */  nostrategy,
 143         /* dump */      nodump,
 144         /* psize */     nopsize,
 145         /* kqfilter */  ttykqfilter
 146 };
 147
 148 Static void ucom_cleanup(struct ucom_softc *);
 149 Static int ucomctl(struct ucom_softc *, int, int);
 150 Static int ucomparam(struct tty *, struct termios *);
 151 Static void ucomstart(struct tty *);
 152 Static void ucomstop(struct tty *, int);
 153 Static void ucom_shutdown(struct ucom_softc *);
 154 Static void ucom_dtr(struct ucom_softc *, int);
 155 Static void ucom_rts(struct ucom_softc *, int);
 156 Static void ucom_break(struct ucom_softc *, int);
 157 Static usbd_status ucomstartread(struct ucom_softc *);
 158 Static void ucomreadcb(usbd_xfer_handle, usbd_private_handle, usbd_status);
 159 Static void ucomwritecb(usbd_xfer_handle, usbd_private_handle, usbd_status);
 160 Static void ucomstopread(struct ucom_softc *);
 161 static void disc_optim(struct tty *, struct termios *, struct ucom_softc *);
 162
 163 devclass_t ucom_devclass;
 164
 165 static moduledata_t ucom_mod = {
 166         "ucom",
 167         NULL,
 168         NULL
 169 };
 170
 171 DECLARE_MODULE(ucom, ucom_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE);
 172 MODULE_DEPEND(ucom, usb, 1, 1, 1);
 173 MODULE_VERSION(ucom, UCOM_MODVER);
 174
 175 int
 176 ucom_attach(struct ucom_softc *sc)
 177 {
 178         struct tty *tp;
 179         int unit;
 180         dev_t dev;
 181
 182         unit = device_get_unit(sc->sc_dev);
 183
 184         sc->sc_tty = tp = ttymalloc(sc->sc_tty);
 185         tp->t_oproc = ucomstart;
 186         tp->t_param = ucomparam;
 187         tp->t_stop = ucomstop;
 188
 189         DPRINTF(("ucom_attach: tty_attach tp = %p\n", tp));
 190
 191         DPRINTF(("ucom_attach: make_dev: ucom%d\n", unit));
 192
 193         cdevsw_add(&ucom_cdevsw, UCOMUNIT_MASK, unit);
 194         dev = make_dev(&ucom_cdevsw, unit | UCOM_CALLOUT_MASK,
 195                         UID_UUCP, GID_DIALER, 0660,
 196                         "ucom%d", unit);
 197         dev->si_tty = tp;
 198
 199         return (0);
 200 }
 201
 202 int
 203 ucom_detach(struct ucom_softc *sc)
 204 {
 205         struct tty *tp = sc->sc_tty;
 206         int s;
 207         int unit;
 208
 209         DPRINTF(("ucom_detach: sc = %p, tp = %p\n", sc, sc->sc_tty));
 210
 211         sc->sc_dying = 1;
 212
 213         if (sc->sc_bulkin_pipe != NULL)
 214                 usbd_abort_pipe(sc->sc_bulkin_pipe);
 215         if (sc->sc_bulkout_pipe != NULL)
 216                 usbd_abort_pipe(sc->sc_bulkout_pipe);
 217
 218         if (tp != NULL) {
 219                 if (tp->t_state & TS_ISOPEN) {
 220                         device_printf(sc->sc_dev,
 221                                       "still open, forcing close\n");
 222                         (*linesw[tp->t_line].l_close)(tp, 0);
 223                         tp->t_gen++;
 224                         ttyclose(tp);
 225                         ttwakeup(tp);
 226                         ttwwakeup(tp);
 227                 }
 228         } else {
 229                 DPRINTF(("ucom_detach: no tty\n"));
 230                 return (0);
 231         }
 232
 233         s = splusb();
 234         if (--sc->sc_refcnt >= 0) {
 235                 /* Wait for processes to go away. */
 236                 usb_detach_wait(USBDEV(sc->sc_dev));
 237         }
 238         splx(s);
 239
 240         unit = device_get_unit(sc->sc_dev);
 241         cdevsw_remove(&ucom_cdevsw, UCOMUNIT_MASK, unit);
 242
 243         return (0);
 244 }
 245
 246 Static void
 247 ucom_shutdown(struct ucom_softc *sc)
 248 {
 249         struct tty *tp = sc->sc_tty;
 250
 251         DPRINTF(("ucom_shutdown\n"));
 252         /*
 253          * Hang up if necessary.  Wait a bit, so the other side has time to
 254          * notice even if we immediately open the port again.
 255          */
 256         if (ISSET(tp->t_cflag, HUPCL)) {
 257                 (void)ucomctl(sc, TIOCM_DTR, DMBIC);
 258                 (void)tsleep(sc, 0, "ucomsd", hz);
 259         }
 260 }
 261
 262 Static int
 263 ucomopen(dev_t dev, int flag, int mode, usb_proc_ptr td)
 264 {
 265         int unit = UCOMUNIT(dev);
 266         struct ucom_softc *sc;
 267         usbd_status err;
 268         struct tty *tp;
 269         int s;
 270         int error;
 271
 272         KKASSERT(td != NULL);
 273
 274         USB_GET_SC_OPEN(ucom, unit, sc);
 275
 276         if (sc->sc_dying)
 277                 return (ENXIO);
 278
 279         tp = sc->sc_tty;
 280
 281         DPRINTF(("%s: ucomopen: tp = %p\n", USBDEVNAME(sc->sc_dev), tp));
 282
 283         if (ISSET(tp->t_state, TS_ISOPEN) &&
 284             ISSET(tp->t_state, TS_XCLUDE) &&
 285             suser(td)
 286         ) {
 287                 return (EBUSY);
 288         }
 289
 290         /*
 291          * Do the following iff this is a first open.
 292          */
 293         s = spltty();
 294         while (sc->sc_opening)
 295                 tsleep(&sc->sc_opening, 0, "ucomop", 0);
 296         sc->sc_opening = 1;
 297
 298         if (!ISSET(tp->t_state, TS_ISOPEN)) {
 299                 struct termios t;
 300
 301                 sc->sc_poll = 0;
 302                 sc->sc_lsr = sc->sc_msr = sc->sc_mcr = 0;
 303
 304                 tp->t_dev = reference_dev(dev);
 305
 306                 /*
 307                  * Initialize the termios status to the defaults.  Add in the
 308                  * sticky bits from TIOCSFLAGS.
 309                  */
 310                 t.c_ispeed = 0;
 311                 t.c_ospeed = TTYDEF_SPEED;
 312                 t.c_cflag = TTYDEF_CFLAG;
 313                 /* Make sure ucomparam() will do something. */
 314                 tp->t_ospeed = 0;
 315                 (void)ucomparam(tp, &t);
 316                 tp->t_iflag = TTYDEF_IFLAG;
 317                 tp->t_oflag = TTYDEF_OFLAG;
 318                 tp->t_lflag = TTYDEF_LFLAG;
 319                 ttychars(tp);
 320                 ttsetwater(tp);
 321
 322                 /*
 323                  * Turn on DTR.  We must always do this, even if carrier is not
 324                  * present, because otherwise we'd have to use TIOCSDTR
 325                  * immediately after setting CLOCAL, which applications do not
 326                  * expect.  We always assert DTR while the device is open
 327                  * unless explicitly requested to deassert it.
 328                  */
 329                 (void)ucomctl(sc, TIOCM_DTR | TIOCM_RTS, DMBIS);
 330
 331                 /* Device specific open */
 332                 if (sc->sc_callback->ucom_open != NULL) {
 333                         error = sc->sc_callback->ucom_open(sc->sc_parent,
 334                                                            sc->sc_portno);
 335                         if (error) {
 336                                 ucom_cleanup(sc);
 337                                 sc->sc_opening = 0;
 338                                 wakeup(&sc->sc_opening);
 339                                 splx(s);
 340                                 return (error);
 341                         }
 342                 }
 343
 344                 DPRINTF(("ucomopen: open pipes in = %d out = %d\n",
 345                          sc->sc_bulkin_no, sc->sc_bulkout_no));
 346
 347                 /* Open the bulk pipes */
 348                 /* Bulk-in pipe */
 349                 err = usbd_open_pipe(sc->sc_iface, sc->sc_bulkin_no, 0,
 350                                      &sc->sc_bulkin_pipe);
 351                 if (err) {
 352                         printf("%s: open bulk in error (addr %d): %s\n",
 353                                USBDEVNAME(sc->sc_dev), sc->sc_bulkin_no,
 354                                usbd_errstr(err));
 355                         error = EIO;
 356                         goto fail_0;
 357                 }
 358                 /* Bulk-out pipe */
 359                 err = usbd_open_pipe(sc->sc_iface, sc->sc_bulkout_no,
 360                                      USBD_EXCLUSIVE_USE, &sc->sc_bulkout_pipe);
 361                 if (err) {
 362                         printf("%s: open bulk out error (addr %d): %s\n",
 363                                USBDEVNAME(sc->sc_dev), sc->sc_bulkout_no,
 364                                usbd_errstr(err));
 365                         error = EIO;
 366                         goto fail_1;
 367                 }
 368
 369                 /* Allocate a request and an input buffer and start reading. */
 370                 sc->sc_ixfer = usbd_alloc_xfer(sc->sc_udev);
 371                 if (sc->sc_ixfer == NULL) {
 372                         error = ENOMEM;
 373                         goto fail_2;
 374                 }
 375
 376                 sc->sc_ibuf = usbd_alloc_buffer(sc->sc_ixfer,
 377                                                 sc->sc_ibufsizepad);
 378                 if (sc->sc_ibuf == NULL) {
 379                         error = ENOMEM;
 380                         goto fail_3;
 381                 }
 382
 383                 sc->sc_oxfer = usbd_alloc_xfer(sc->sc_udev);
 384                 if (sc->sc_oxfer == NULL) {
 385                         error = ENOMEM;
 386                         goto fail_3;
 387                 }
 388
 389                 sc->sc_obuf = usbd_alloc_buffer(sc->sc_oxfer,
 390                                                 sc->sc_obufsize +
 391                                                 sc->sc_opkthdrlen);
 392                 if (sc->sc_obuf == NULL) {
 393                         error = ENOMEM;
 394                         goto fail_4;
 395                 }
 396
 397                 /*
 398                  * Handle initial DCD.
 399                  */
 400                 if (ISSET(sc->sc_msr, UMSR_DCD) ||
 401                     (minor(dev) & UCOM_CALLOUT_MASK))
 402                         (*linesw[tp->t_line].l_modem)(tp, 1);
 403
 404                 ucomstartread(sc);
 405         }
 406
 407         sc->sc_opening = 0;
 408         wakeup(&sc->sc_opening);
 409         splx(s);
 410
 411         error = ttyopen(dev, tp);
 412         if (error)
 413                 goto bad;
 414
 415         error = (*linesw[tp->t_line].l_open)(dev, tp);
 416         if (error)
 417                 goto bad;
 418
 419         disc_optim(tp, &tp->t_termios, sc);
 420
 421         DPRINTF(("%s: ucomopen: success\n", USBDEVNAME(sc->sc_dev)));
 422
 423         sc->sc_poll = 1;
 424         sc->sc_refcnt++;
 425
 426         return (0);
 427
 428 fail_4:
 429         usbd_free_xfer(sc->sc_oxfer);
 430         sc->sc_oxfer = NULL;
 431 fail_3:
 432         usbd_free_xfer(sc->sc_ixfer);
 433         sc->sc_ixfer = NULL;
 434 fail_2:
 435         usbd_close_pipe(sc->sc_bulkout_pipe);
 436         sc->sc_bulkout_pipe = NULL;
 437 fail_1:
 438         usbd_close_pipe(sc->sc_bulkin_pipe);
 439         sc->sc_bulkin_pipe = NULL;
 440 fail_0:
 441         sc->sc_opening = 0;
 442         wakeup(&sc->sc_opening);
 443         splx(s);
 444         return (error);
 445
 446 bad:
 447         if (!ISSET(tp->t_state, TS_ISOPEN)) {
 448                 /*
 449                  * We failed to open the device, and nobody else had it opened.
 450                  * Clean up the state as appropriate.
 451                  */
 452                 ucom_cleanup(sc);
 453         }
 454
 455         DPRINTF(("%s: ucomopen: failed\n", USBDEVNAME(sc->sc_dev)));
 456
 457         return (error);
 458 }
 459
 460 static int
 461 ucomclose(dev_t dev, int flag, int mode, usb_proc_ptr p)
 462 {
 463         struct ucom_softc *sc;
 464         struct tty *tp;
 465         int s;
 466
 467         USB_GET_SC(ucom, UCOMUNIT(dev), sc);
 468
 469         tp = sc->sc_tty;
 470
 471         DPRINTF(("%s: ucomclose: unit = %d\n",
 472                 USBDEVNAME(sc->sc_dev), UCOMUNIT(dev)));
 473
 474         if (!ISSET(tp->t_state, TS_ISOPEN))
 475                 goto quit;
 476
 477         s = spltty();
 478         (*linesw[tp->t_line].l_close)(tp, flag);
 479         disc_optim(tp, &tp->t_termios, sc);
 480         ttyclose(tp);
 481         splx(s);
 482
 483         if (sc->sc_dying)
 484                 goto quit;
 485
 486         if (!ISSET(tp->t_state, TS_ISOPEN)) {
 487                 /*
 488                  * Although we got a last close, the device may still be in
 489                  * use; e.g. if this was the dialout node, and there are still
 490                  * processes waiting for carrier on the non-dialout node.
 491                  */
 492                 ucom_cleanup(sc);
 493         }
 494
 495         if (sc->sc_callback->ucom_close != NULL)
 496                 sc->sc_callback->ucom_close(sc->sc_parent, sc->sc_portno);
 497
 498 quit:
 499         if (tp->t_dev) {
 500                 release_dev(tp->t_dev);
 501                 tp->t_dev = NULL;
 502         }
 503
 504         if (--sc->sc_refcnt < 0)
 505                 usb_detach_wakeup(USBDEV(sc->sc_dev));
 506
 507         return (0);
 508 }
 509
 510 static int
 511 ucomread(dev_t dev, struct uio *uio, int flag)
 512 {
 513         struct ucom_softc *sc;
 514         struct tty *tp;
 515         int error;
 516
 517         USB_GET_SC(ucom, UCOMUNIT(dev), sc);
 518         tp = sc->sc_tty;
 519
 520         DPRINTF(("ucomread: tp = %p, flag = 0x%x\n", tp, flag));
 521
 522         if (sc->sc_dying)
 523                 return (EIO);
 524
 525         error = (*linesw[tp->t_line].l_read)(tp, uio, flag);
 526
 527         DPRINTF(("ucomread: error = %d\n", error));
 528
 529         return (error);
 530 }
 531
 532 static int
 533 ucomwrite(dev_t dev, struct uio *uio, int flag)
 534 {
 535         struct ucom_softc *sc;
 536         struct tty *tp;
 537         int error;
 538
 539         USB_GET_SC(ucom, UCOMUNIT(dev), sc);
 540         tp = sc->sc_tty;
 541
 542         DPRINTF(("ucomwrite: tp = %p, flag = 0x%x\n", tp, flag));
 543
 544         if (sc->sc_dying)
 545                 return (EIO);
 546
 547         error = (*linesw[tp->t_line].l_write)(tp, uio, flag);
 548
 549         DPRINTF(("ucomwrite: error = %d\n", error));
 550
 551         return (error);
 552 }
 553
 554 static int
 555 ucomioctl(dev_t dev, u_long cmd, caddr_t data, int flag, usb_proc_ptr p)
 556 {
 557         struct ucom_softc *sc;
 558         struct tty *tp;
 559         int error;
 560         int s;
 561         int d;
 562
 563         USB_GET_SC(ucom, UCOMUNIT(dev), sc);
 564         tp = sc->sc_tty;
 565
 566         if (sc->sc_dying)
 567                 return (EIO);
 568
 569         DPRINTF(("ucomioctl: cmd = 0x%08lx\n", cmd));
 570
 571         error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, p);
 572         if (error != ENOIOCTL) {
 573                 DPRINTF(("ucomioctl: l_ioctl: error = %d\n", error));
 574                 return (error);
 575         }
 576
 577         s = spltty();
 578
 579         error = ttioctl(tp, cmd, data, flag);
 580         disc_optim(tp, &tp->t_termios, sc);
 581         if (error != ENOIOCTL) {
 582                 splx(s);
 583                 DPRINTF(("ucomioctl: ttioctl: error = %d\n", error));
 584                 return (error);
 585         }
 586
 587         if (sc->sc_callback->ucom_ioctl != NULL) {
 588                 /* XXX splx(s) ? */
 589                 error = sc->sc_callback->ucom_ioctl(sc->sc_parent,
 590                                                     sc->sc_portno,
 591                                                     cmd, data, flag, p);
 592                 if (error >= 0)
 593                         return (error);
 594         }
 595
 596         error = 0;
 597
 598         DPRINTF(("ucomioctl: our cmd = 0x%08lx\n", cmd));
 599
 600         switch (cmd) {
 601         case TIOCSBRK:
 602                 DPRINTF(("ucomioctl: TIOCSBRK\n"));
 603                 ucom_break(sc, 1);
 604                 break;
 605         case TIOCCBRK:
 606                 DPRINTF(("ucomioctl: TIOCCBRK\n"));
 607                 ucom_break(sc, 0);
 608                 break;
 609
 610         case TIOCSDTR:
 611                 DPRINTF(("ucomioctl: TIOCSDTR\n"));
 612                 (void)ucomctl(sc, TIOCM_DTR, DMBIS);
 613                 break;
 614         case TIOCCDTR:
 615                 DPRINTF(("ucomioctl: TIOCCDTR\n"));
 616                 (void)ucomctl(sc, TIOCM_DTR, DMBIC);
 617                 break;
 618
 619         case TIOCMSET:
 620                 d = *(int *)data;
 621                 DPRINTF(("ucomioctl: TIOCMSET, 0x%x\n", d));
 622                 (void)ucomctl(sc, d, DMSET);
 623                 break;
 624         case TIOCMBIS:
 625                 d = *(int *)data;
 626                 DPRINTF(("ucomioctl: TIOCMBIS, 0x%x\n", d));
 627                 (void)ucomctl(sc, d, DMBIS);
 628                 break;
 629         case TIOCMBIC:
 630                 d = *(int *)data;
 631                 DPRINTF(("ucomioctl: TIOCMBIC, 0x%x\n", d));
 632                 (void)ucomctl(sc, d, DMBIC);
 633                 break;
 634         case TIOCMGET:
 635                 d = ucomctl(sc, 0, DMGET);
 636                 DPRINTF(("ucomioctl: TIOCMGET, 0x%x\n", d));
 637                 *(int *)data = d;
 638                 break;
 639
 640         default:
 641                 DPRINTF(("ucomioctl: error: our cmd = 0x%08lx\n", cmd));
 642                 error = ENOTTY;
 643                 break;
 644         }
 645
 646         splx(s);
 647
 648         return (error);
 649 }
 650
 651 Static int
 652 ucomctl(struct ucom_softc *sc, int bits, int how)
 653 {
 654         int     mcr;
 655         int     msr;
 656         int     onoff;
 657
 658         DPRINTF(("ucomctl: bits = 0x%x, how = %d\n", bits, how));
 659
 660         if (how == DMGET) {
 661                 SET(bits, TIOCM_LE);            /* always set TIOCM_LE bit */
 662                 DPRINTF(("ucomctl: DMGET: LE"));
 663
 664                 mcr = sc->sc_mcr;
 665                 if (ISSET(mcr, UMCR_DTR)) {
 666                         SET(bits, TIOCM_DTR);
 667                         DPRINTF((" DTR"));
 668                 }
 669                 if (ISSET(mcr, UMCR_RTS)) {
 670                         SET(bits, TIOCM_RTS);
 671                         DPRINTF((" RTS"));
 672                 }
 673
 674                 msr = sc->sc_msr;
 675                 if (ISSET(msr, UMSR_CTS)) {
 676                         SET(bits, TIOCM_CTS);
 677                         DPRINTF((" CTS"));
 678                 }
 679                 if (ISSET(msr, UMSR_DCD)) {
 680                         SET(bits, TIOCM_CD);
 681                         DPRINTF((" CD"));
 682                 }
 683                 if (ISSET(msr, UMSR_DSR)) {
 684                         SET(bits, TIOCM_DSR);
 685                         DPRINTF((" DSR"));
 686                 }
 687                 if (ISSET(msr, UMSR_RI)) {
 688                         SET(bits, TIOCM_RI);
 689                         DPRINTF((" RI"));
 690                 }
 691
 692                 DPRINTF(("\n"));
 693
 694                 return (bits);
 695         }
 696
 697         mcr = 0;
 698         if (ISSET(bits, TIOCM_DTR))
 699                 SET(mcr, UMCR_DTR);
 700         if (ISSET(bits, TIOCM_RTS))
 701                 SET(mcr, UMCR_RTS);
 702
 703         switch (how) {
 704         case DMSET:
 705                 sc->sc_mcr = mcr;
 706                 break;
 707         case DMBIS:
 708                 sc->sc_mcr |= mcr;
 709                 break;
 710         case DMBIC:
 711                 sc->sc_mcr &= ~mcr;
 712                 break;
 713         }
 714
 715         onoff = ISSET(sc->sc_mcr, UMCR_DTR) ? 1 : 0;
 716         ucom_dtr(sc, onoff);
 717
 718         onoff = ISSET(sc->sc_mcr, UMCR_RTS) ? 1 : 0;
 719         ucom_rts(sc, onoff);
 720
 721         return (0);
 722 }
 723
 724 Static void
 725 ucom_break(struct ucom_softc *sc, int onoff)
 726 {
 727         DPRINTF(("ucom_break: onoff = %d\n", onoff));
 728
 729         if (sc->sc_callback->ucom_set == NULL)
 730                 return;
 731         sc->sc_callback->ucom_set(sc->sc_parent, sc->sc_portno,
 732                                   UCOM_SET_BREAK, onoff);
 733 }
 734
 735 Static void
 736 ucom_dtr(struct ucom_softc *sc, int onoff)
 737 {
 738         DPRINTF(("ucom_dtr: onoff = %d\n", onoff));
 739
 740         if (sc->sc_callback->ucom_set == NULL)
 741                 return;
 742         sc->sc_callback->ucom_set(sc->sc_parent, sc->sc_portno,
 743                                   UCOM_SET_DTR, onoff);
 744 }
 745
 746 Static void
 747 ucom_rts(struct ucom_softc *sc, int onoff)
 748 {
 749         DPRINTF(("ucom_rts: onoff = %d\n", onoff));
 750
 751         if (sc->sc_callback->ucom_set == NULL)
 752                 return;
 753         sc->sc_callback->ucom_set(sc->sc_parent, sc->sc_portno,
 754                                   UCOM_SET_RTS, onoff);
 755 }
 756
 757 void
 758 ucom_status_change(struct ucom_softc *sc)
 759 {
 760         struct tty *tp = sc->sc_tty;
 761         u_char old_msr;
 762         int onoff;
 763
 764         if (sc->sc_callback->ucom_get_status == NULL) {
 765                 sc->sc_lsr = 0;
 766                 sc->sc_msr = 0;
 767                 return;
 768         }
 769
 770         old_msr = sc->sc_msr;
 771         sc->sc_callback->ucom_get_status(sc->sc_parent, sc->sc_portno,
 772                                          &sc->sc_lsr, &sc->sc_msr);
 773         if (ISSET((sc->sc_msr ^ old_msr), UMSR_DCD)) {
 774                 if (sc->sc_poll == 0)
 775                         return;
 776                 onoff = ISSET(sc->sc_msr, UMSR_DCD) ? 1 : 0;
 777                 DPRINTF(("ucom_status_change: DCD changed to %d\n", onoff));
 778                 (*linesw[tp->t_line].l_modem)(tp, onoff);
 779         }
 780 }
 781
 782 Static int
 783 ucomparam(struct tty *tp, struct termios *t)
 784 {
 785         struct ucom_softc *sc;
 786         int error;
 787         usbd_status uerr;
 788
 789         USB_GET_SC(ucom, UCOMUNIT(tp->t_dev), sc);
 790
 791         if (sc->sc_dying)
 792                 return (EIO);
 793
 794         DPRINTF(("ucomparam: sc = %p\n", sc));
 795
 796         /* Check requested parameters. */
 797         if (t->c_ospeed < 0) {
 798                 DPRINTF(("ucomparam: negative ospeed\n"));
 799                 return (EINVAL);
 800         }
 801         if (t->c_ispeed && t->c_ispeed != t->c_ospeed) {
 802                 DPRINTF(("ucomparam: mismatch ispeed and ospeed\n"));
 803                 return (EINVAL);
 804         }
 805
 806         /*
 807          * If there were no changes, don't do anything.  This avoids dropping
 808          * input and improves performance when all we did was frob things like
 809          * VMIN and VTIME.
 810          */
 811         if (tp->t_ospeed == t->c_ospeed &&
 812             tp->t_cflag == t->c_cflag)
 813                 return (0);
 814
 815         /* And copy to tty. */
 816         tp->t_ispeed = 0;
 817         tp->t_ospeed = t->c_ospeed;
 818         tp->t_cflag = t->c_cflag;
 819
 820         if (sc->sc_callback->ucom_param == NULL)
 821                 return (0);
 822
 823         ucomstopread(sc);
 824
 825         error = sc->sc_callback->ucom_param(sc->sc_parent, sc->sc_portno, t);
 826         if (error) {
 827                 DPRINTF(("ucomparam: callback: error = %d\n", error));
 828                 return (error);
 829         }
 830
 831         ttsetwater(tp);
 832
 833         if (t->c_cflag & CRTS_IFLOW) {
 834                 sc->sc_state |= UCS_RTS_IFLOW;
 835         } else if (sc->sc_state & UCS_RTS_IFLOW) {
 836                 sc->sc_state &= ~UCS_RTS_IFLOW;
 837                 (void)ucomctl(sc, UMCR_RTS, DMBIS);
 838         }
 839
 840         disc_optim(tp, t, sc);
 841
 842         uerr = ucomstartread(sc);
 843         if (uerr != USBD_NORMAL_COMPLETION)
 844                 return (EIO);
 845
 846         return (0);
 847 }
 848
 849 Static void
 850 ucomstart(struct tty *tp)
 851 {
 852         struct ucom_softc *sc;
 853         struct cblock *cbp;
 854         usbd_status err;
 855         int s;
 856         u_char *data;
 857         int cnt;
 858
 859         USB_GET_SC(ucom, UCOMUNIT(tp->t_dev), sc);
 860         DPRINTF(("ucomstart: sc = %p\n", sc));
 861
 862         if (sc->sc_dying)
 863                 return;
 864
 865         s = spltty();
 866
 867         if (tp->t_state & TS_TBLOCK) {
 868                 if (ISSET(sc->sc_mcr, UMCR_RTS) &&
 869                     ISSET(sc->sc_state, UCS_RTS_IFLOW)) {
 870                         DPRINTF(("ucomstart: clear RTS\n"));
 871                         (void)ucomctl(sc, UMCR_RTS, DMBIC);
 872                 }
 873         } else {
 874                 if (!ISSET(sc->sc_mcr, UMCR_RTS) &&
 875                     tp->t_rawq.c_cc <= tp->t_ilowat &&
 876                     ISSET(sc->sc_state, UCS_RTS_IFLOW)) {
 877                         DPRINTF(("ucomstart: set RTS\n"));
 878                         (void)ucomctl(sc, UMCR_RTS, DMBIS);
 879                 }
 880         }
 881
 882         if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP)) {
 883                 ttwwakeup(tp);
 884                 DPRINTF(("ucomstart: stopped\n"));
 885                 goto out;
 886         }
 887
 888         if (tp->t_outq.c_cc <= tp->t_olowat) {
 889                 if (ISSET(tp->t_state, TS_SO_OLOWAT)) {
 890                         CLR(tp->t_state, TS_SO_OLOWAT);
 891                         wakeup(TSA_OLOWAT(tp));
 892                 }
 893                 selwakeuppri(&tp->t_wsel, TTIPRI);
 894                 if (tp->t_outq.c_cc == 0) {
 895                         if (ISSET(tp->t_state, TS_BUSY | TS_SO_OCOMPLETE) ==
 896                             TS_SO_OCOMPLETE && tp->t_outq.c_cc == 0) {
 897                                 CLR(tp->t_state, TS_SO_OCOMPLETE);
 898                                 wakeup(TSA_OCOMPLETE(tp));
 899                         }
 900                         goto out;
 901                 }
 902         }
 903
 904         /* Grab the first contiguous region of buffer space. */
 905         data = tp->t_outq.c_cf;
 906         cbp = (struct cblock *) ((intptr_t) tp->t_outq.c_cf & ~CROUND);
 907         cnt = min((char *) (cbp+1) - tp->t_outq.c_cf, tp->t_outq.c_cc);
 908
 909         if (cnt == 0) {
 910                 DPRINTF(("ucomstart: cnt == 0\n"));
 911                 goto out;
 912         }
 913
 914         SET(tp->t_state, TS_BUSY);
 915
 916         if (cnt > sc->sc_obufsize) {
 917                 DPRINTF(("ucomstart: big buffer %d chars\n", cnt));
 918                 cnt = sc->sc_obufsize;
 919         }
 920         if (sc->sc_callback->ucom_write != NULL)
 921                 sc->sc_callback->ucom_write(sc->sc_parent, sc->sc_portno,
 922                                             sc->sc_obuf, data, &cnt);
 923         else
 924                 memcpy(sc->sc_obuf, data, cnt);
 925
 926         DPRINTF(("ucomstart: %d chars\n", cnt));
 927         usbd_setup_xfer(sc->sc_oxfer, sc->sc_bulkout_pipe,
 928                         (usbd_private_handle)sc, sc->sc_obuf, cnt,
 929                         USBD_NO_COPY, USBD_NO_TIMEOUT, ucomwritecb);
 930         /* What can we do on error? */
 931         err = usbd_transfer(sc->sc_oxfer);
 932         if (err != USBD_IN_PROGRESS)
 933                 printf("ucomstart: err=%s\n", usbd_errstr(err));
 934
 935         ttwwakeup(tp);
 936
 937     out:
 938         splx(s);
 939 }
 940
 941 Static void
 942 ucomstop(struct tty *tp, int flag)
 943 {
 944         struct ucom_softc *sc;
 945         int s;
 946
 947         USB_GET_SC(ucom, UCOMUNIT(tp->t_dev), sc);
 948
 949         DPRINTF(("ucomstop: %d\n", flag));
 950
 951         if (flag & FREAD) {
 952                 /*
 953                  * This is just supposed to flush pending receive data,
 954                  * not stop the reception of data entirely!
 955                  */
 956                 DPRINTF(("ucomstop: read\n"));
 957                 ucomstopread(sc);
 958                 ucomstartread(sc);
 959         }
 960
 961         if (flag & FWRITE) {
 962                 DPRINTF(("ucomstop: write\n"));
 963                 s = spltty();
 964                 if (ISSET(tp->t_state, TS_BUSY)) {
 965                         /* XXX do what? */
 966                         if (!ISSET(tp->t_state, TS_TTSTOP))
 967                                 SET(tp->t_state, TS_FLUSH);
 968                 }
 969                 splx(s);
 970         }
 971
 972         DPRINTF(("ucomstop: done\n"));
 973 }
 974
 975 Static void
 976 ucomwritecb(usbd_xfer_handle xfer, usbd_private_handle p, usbd_status status)
 977 {
 978         struct ucom_softc *sc = (struct ucom_softc *)p;
 979         struct tty *tp = sc->sc_tty;
 980         u_int32_t cc;
 981         int s;
 982
 983         DPRINTF(("ucomwritecb: status = %d\n", status));
 984
 985         if (status == USBD_CANCELLED || sc->sc_dying)
 986                 goto error;
 987
 988         if (status != USBD_NORMAL_COMPLETION) {
 989                 printf("%s: ucomwritecb: %s\n",
 990                        USBDEVNAME(sc->sc_dev), usbd_errstr(status));
 991                 if (status == USBD_STALLED)
 992                         usbd_clear_endpoint_stall_async(sc->sc_bulkin_pipe);
 993                 /*
 994                  * XXX.  We may need a flag to sequence ucomstopread() and
 995                  * ucomstartread() to handle the case where ucomstartread()
 996                  * is called after ucomstopread() but before the request has
 997                  * been properly canceled?
 998                  */
 999                 goto error;
1000         }
1001
1002         usbd_get_xfer_status(xfer, NULL, NULL, &cc, NULL);
1003         DPRINTF(("ucomwritecb: cc = %d\n", cc));
1004         if (cc <= sc->sc_opkthdrlen) {
1005                 printf("%s: sent size too small, cc = %d\n",
1006                         USBDEVNAME(sc->sc_dev), cc);
1007                 goto error;
1008         }
1009
1010         /* convert from USB bytes to tty bytes */
1011         cc -= sc->sc_opkthdrlen;
1012
1013         s = spltty();
1014         CLR(tp->t_state, TS_BUSY);
1015         if (ISSET(tp->t_state, TS_FLUSH))
1016                 CLR(tp->t_state, TS_FLUSH);
1017         else
1018                 ndflush(&tp->t_outq, cc);
1019         (*linesw[tp->t_line].l_start)(tp);
1020         splx(s);
1021
1022         return;
1023
1024   error:
1025         s = spltty();
1026         CLR(tp->t_state, TS_BUSY);
1027         splx(s);
1028         return;
1029 }
1030
1031 Static usbd_status
1032 ucomstartread(struct ucom_softc *sc)
1033 {
1034         usbd_status err;
1035
1036         DPRINTF(("ucomstartread: start\n"));
1037
1038         sc->sc_state &= ~UCS_RXSTOP;
1039
1040         if (sc->sc_bulkin_pipe == NULL)
1041                 return (USBD_NORMAL_COMPLETION);
1042
1043         usbd_setup_xfer(sc->sc_ixfer, sc->sc_bulkin_pipe,
1044                         (usbd_private_handle)sc,
1045                         sc->sc_ibuf, sc->sc_ibufsize,
1046                         USBD_SHORT_XFER_OK | USBD_NO_COPY,
1047                         USBD_NO_TIMEOUT, ucomreadcb);
1048
1049         err = usbd_transfer(sc->sc_ixfer);
1050         if (err != USBD_IN_PROGRESS) {
1051                 DPRINTF(("ucomstartread: err = %s\n", usbd_errstr(err)));
1052                 return (err);
1053         }
1054
1055         return (USBD_NORMAL_COMPLETION);
1056 }
1057
1058 Static void
1059 ucomreadcb(usbd_xfer_handle xfer, usbd_private_handle p, usbd_status status)
1060 {
1061         struct ucom_softc *sc = (struct ucom_softc *)p;
1062         struct tty *tp = sc->sc_tty;
1063         int (*rint) (int c, struct tty *tp) = linesw[tp->t_line].l_rint;
1064         usbd_status err;
1065         u_int32_t cc;
1066         u_char *cp;
1067         int lostcc;
1068         int s;
1069
1070         DPRINTF(("ucomreadcb: status = %d\n", status));
1071
1072         if (status != USBD_NORMAL_COMPLETION) {
1073                 if (!(sc->sc_state & UCS_RXSTOP))
1074                         printf("%s: ucomreadcb: %s\n",
1075                                USBDEVNAME(sc->sc_dev), usbd_errstr(status));
1076                 if (status == USBD_STALLED)
1077                         usbd_clear_endpoint_stall_async(sc->sc_bulkin_pipe);
1078                 /* XXX we should restart after some delay. */
1079                 return;
1080         }
1081
1082         usbd_get_xfer_status(xfer, NULL, (void **)&cp, &cc, NULL);
1083         DPRINTF(("ucomreadcb: got %d chars, tp = %p\n", cc, tp));
1084         if (cc == 0)
1085                 goto resubmit;
1086
1087         if (sc->sc_callback->ucom_read != NULL) {
1088                 sc->sc_callback->ucom_read(sc->sc_parent, sc->sc_portno,
1089                                            &cp, &cc);
1090         }
1091
1092         if (cc > sc->sc_ibufsize) {
1093                 printf("%s: invalid receive data size, %d chars\n",
1094                         USBDEVNAME(sc->sc_dev), cc);
1095                 goto resubmit;
1096         }
1097         if (cc < 1)
1098                 goto resubmit;
1099
1100         s = spltty();
1101         if (tp->t_state & TS_CAN_BYPASS_L_RINT) {
1102                 if (tp->t_rawq.c_cc + cc > tp->t_ihiwat
1103                     && (sc->sc_state & UCS_RTS_IFLOW
1104                         || tp->t_iflag & IXOFF)
1105                     && !(tp->t_state & TS_TBLOCK))
1106                         ttyblock(tp);
1107                 lostcc = b_to_q((char *)cp, cc, &tp->t_rawq);
1108                 tp->t_rawcc += cc;
1109                 if (sc->hotchar) {
1110                         while (cc) {
1111                                 if (*cp == sc->hotchar)
1112                                         break;
1113                                 --cc;
1114                                 ++cp;
1115                         }
1116                         if (cc)
1117                                 setsofttty();
1118                 }
1119                 ttwakeup(tp);
1120                 if (tp->t_state & TS_TTSTOP
1121                     && (tp->t_iflag & IXANY
1122                         || tp->t_cc[VSTART] == tp->t_cc[VSTOP])) {
1123                         tp->t_state &= ~TS_TTSTOP;
1124                         tp->t_lflag &= ~FLUSHO;
1125                         ucomstart(tp);
1126                 }
1127                 if (lostcc > 0)
1128                         printf("%s: lost %d chars\n", USBDEVNAME(sc->sc_dev),
1129                                lostcc);
1130         } else {
1131                 /* Give characters to tty layer. */
1132                 while (cc > 0) {
1133                         DPRINTFN(7, ("ucomreadcb: char = 0x%02x\n", *cp));
1134                         if ((*rint)(*cp, tp) == -1) {
1135                                 /* XXX what should we do? */
1136                                 printf("%s: lost %d chars\n",
1137                                        USBDEVNAME(sc->sc_dev), cc);
1138                                 break;
1139                         }
1140                         cc--;
1141                         cp++;
1142                 }
1143         }
1144         splx(s);
1145
1146 resubmit:
1147         err = ucomstartread(sc);
1148         if (err) {
1149                 printf("%s: read start failed\n", USBDEVNAME(sc->sc_dev));
1150                 /* XXX what should we dow now? */
1151         }
1152
1153         if ((sc->sc_state & UCS_RTS_IFLOW) && !ISSET(sc->sc_mcr, UMCR_RTS)
1154             && !(tp->t_state & TS_TBLOCK))
1155                 ucomctl(sc, UMCR_RTS, DMBIS);
1156 }
1157
1158 Static void
1159 ucom_cleanup(struct ucom_softc *sc)
1160 {
1161         DPRINTF(("ucom_cleanup: closing pipes\n"));
1162
1163         ucom_shutdown(sc);
1164         if (sc->sc_bulkin_pipe != NULL) {
1165                 usbd_abort_pipe(sc->sc_bulkin_pipe);
1166                 usbd_close_pipe(sc->sc_bulkin_pipe);
1167                 sc->sc_bulkin_pipe = NULL;
1168         }
1169         if (sc->sc_bulkout_pipe != NULL) {
1170                 usbd_abort_pipe(sc->sc_bulkout_pipe);
1171                 usbd_close_pipe(sc->sc_bulkout_pipe);
1172                 sc->sc_bulkout_pipe = NULL;
1173         }
1174         if (sc->sc_ixfer != NULL) {
1175                 usbd_free_xfer(sc->sc_ixfer);
1176                 sc->sc_ixfer = NULL;
1177         }
1178         if (sc->sc_oxfer != NULL) {
1179                 usbd_free_xfer(sc->sc_oxfer);
1180                 sc->sc_oxfer = NULL;
1181         }
1182 }
1183
1184 Static void
1185 ucomstopread(struct ucom_softc *sc)
1186 {
1187         usbd_status err;
1188
1189         DPRINTF(("ucomstopread: enter\n"));
1190
1191         if (!(sc->sc_state & UCS_RXSTOP)) {
1192                 sc->sc_state |= UCS_RXSTOP;
1193                 if (sc->sc_bulkin_pipe == NULL) {
1194                         DPRINTF(("ucomstopread: bulkin pipe NULL\n"));
1195                         return;
1196                 }
1197                 err = usbd_abort_pipe(sc->sc_bulkin_pipe);
1198                 if (err) {
1199                         DPRINTF(("ucomstopread: err = %s\n",
1200                                  usbd_errstr(err)));
1201                 }
1202         }
1203
1204         DPRINTF(("ucomstopread: leave\n"));
1205 }
1206
1207 static void
1208 disc_optim(struct tty *tp, struct termios *t, struct ucom_softc *sc)
1209 {
1210         if (!(t->c_iflag & (ICRNL | IGNCR | IMAXBEL | INLCR | ISTRIP | IXON))
1211             && (!(t->c_iflag & BRKINT) || (t->c_iflag & IGNBRK))
1212             && (!(t->c_iflag & PARMRK)
1213                 || (t->c_iflag & (IGNPAR | IGNBRK)) == (IGNPAR | IGNBRK))
1214             && !(t->c_lflag & (ECHO | ICANON | IEXTEN | ISIG | PENDIN))
1215             && linesw[tp->t_line].l_rint == ttyinput) {
1216                 DPRINTF(("disc_optim: bypass l_rint\n"));
1217                 tp->t_state |= TS_CAN_BYPASS_L_RINT;
1218         } else {
1219                 DPRINTF(("disc_optim: can't bypass l_rint\n"));
1220                 tp->t_state &= ~TS_CAN_BYPASS_L_RINT;
1221         }
1222         sc->hotchar = linesw[tp->t_line].l_hotchar;
1223 }