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 1.32 2007/11/05 19:09:43 hasso 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/fcntl.h>
  76 #include <sys/conf.h>
  77 #include <sys/tty.h>
  78 #include <sys/clist.h>
  79 #include <sys/file.h>
  80 #include <sys/select.h>
  81 #include <sys/proc.h>
  82 #include <sys/priv.h>
  83 #include <sys/poll.h>
  84 #include <sys/sysctl.h>
  85 #include <sys/thread2.h>
  86
  87 #include <bus/usb/usb.h>
  88 #include <bus/usb/usbcdc.h>
  89
  90 #include <bus/usb/usbdi.h>
  91 #include <bus/usb/usbdi_util.h>
  92 #include <bus/usb/usb_quirks.h>
  93
  94 #include "ucomvar.h"
  95
  96 #ifdef USB_DEBUG
  97 static int      ucomdebug = 0;
  98 SYSCTL_NODE(_hw_usb, OID_AUTO, ucom, CTLFLAG_RW, 0, "USB ucom");
  99 SYSCTL_INT(_hw_usb_ucom, OID_AUTO, debug, CTLFLAG_RW,
 100            &ucomdebug, 0, "ucom debug level");
 101 #define DPRINTF(x)      do { \
 102                                 if (ucomdebug) \
 103                                         kprintf x; \
 104                         } while (0)
 105
 106 #define DPRINTFN(n, x)  do { \
 107                                 if (ucomdebug > (n)) \
 108                                         kprintf x; \
 109                         } while (0)
 110 #else
 111 #define DPRINTF(x)
 112 #define DPRINTFN(n, x)
 113 #endif
 114
 115 static d_open_t  ucomopen;
 116 static d_close_t ucomclose;
 117 static d_read_t  ucomread;
 118 static d_write_t ucomwrite;
 119 static d_ioctl_t ucomioctl;
 120
 121 #define UCOM_CDEV_MAJOR  138
 122
 123 static struct dev_ops ucom_ops = {
 124         { "ucom", UCOM_CDEV_MAJOR, D_TTY | D_KQFILTER },
 125         .d_open =       ucomopen,
 126         .d_close =      ucomclose,
 127         .d_read =       ucomread,
 128         .d_write =      ucomwrite,
 129         .d_ioctl =      ucomioctl,
 130         .d_poll =       ttypoll,
 131         .d_kqfilter =   ttykqfilter,
 132         .d_revoke =     ttyrevoke
 133 };
 134
 135 static void ucom_cleanup(struct ucom_softc *);
 136 static int ucomctl(struct ucom_softc *, int, int);
 137 static int ucomparam(struct tty *, struct termios *);
 138 static void ucomstart(struct tty *);
 139 static void ucomstop(struct tty *, int);
 140 static void ucom_shutdown(struct ucom_softc *);
 141 static void ucom_dtr(struct ucom_softc *, int);
 142 static void ucom_rts(struct ucom_softc *, int);
 143 static void ucom_break(struct ucom_softc *, int);
 144 static usbd_status ucomstartread(struct ucom_softc *);
 145 static void ucomreadcb(usbd_xfer_handle, usbd_private_handle, usbd_status);
 146 static void ucomwritecb(usbd_xfer_handle, usbd_private_handle, usbd_status);
 147 static void ucomstopread(struct ucom_softc *);
 148 static void disc_optim(struct tty *, struct termios *, struct ucom_softc *);
 149
 150 devclass_t ucom_devclass;
 151
 152 static moduledata_t ucom_mod = {
 153         "ucom",
 154         NULL,
 155         NULL
 156 };
 157
 158 DECLARE_MODULE(ucom, ucom_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE);
 159 MODULE_DEPEND(ucom, usb, 1, 1, 1);
 160 MODULE_VERSION(ucom, UCOM_MODVER);
 161
 162 int
 163 ucom_attach(struct ucom_softc *sc)
 164 {
 165         struct tty *tp;
 166         int unit;
 167         cdev_t dev;
 168
 169         unit = device_get_unit(sc->sc_dev);
 170
 171         sc->sc_tty = tp = ttymalloc(sc->sc_tty);
 172         tp->t_oproc = ucomstart;
 173         tp->t_param = ucomparam;
 174         tp->t_stop = ucomstop;
 175
 176         DPRINTF(("ucom_attach: tty_attach tp = %p\n", tp));
 177
 178         DPRINTF(("ucom_attach: make_dev: ucom%d\n", unit));
 179
 180         dev_ops_add(&ucom_ops, UCOMUNIT_MASK, unit);
 181         dev = make_dev(&ucom_ops, unit | UCOM_CALLOUT_MASK,
 182                         UID_UUCP, GID_DIALER, 0660,
 183                         "ucom%d", unit);
 184         dev->si_tty = tp;
 185
 186         return (0);
 187 }
 188
 189 int
 190 ucom_detach(struct ucom_softc *sc)
 191 {
 192         struct tty *tp = sc->sc_tty;
 193         int unit;
 194
 195         DPRINTF(("ucom_detach: sc = %p, tp = %p\n", sc, sc->sc_tty));
 196
 197         sc->sc_dying = 1;
 198
 199         if (sc->sc_bulkin_pipe != NULL)
 200                 usbd_abort_pipe(sc->sc_bulkin_pipe);
 201         if (sc->sc_bulkout_pipe != NULL)
 202                 usbd_abort_pipe(sc->sc_bulkout_pipe);
 203
 204         if (tp != NULL) {
 205                 if (tp->t_state & TS_ISOPEN) {
 206                         device_printf(sc->sc_dev,
 207                                       "still open, forcing close\n");
 208                         (*linesw[tp->t_line].l_close)(tp, 0);
 209                         ttyclose(tp);
 210                 }
 211         } else {
 212                 DPRINTF(("ucom_detach: no tty\n"));
 213                 return (0);
 214         }
 215
 216         crit_enter();
 217         if (--sc->sc_refcnt >= 0) {
 218                 /* Wait for processes to go away. */
 219                 usb_detach_wait(sc->sc_dev);
 220         }
 221         crit_exit();
 222
 223         unit = device_get_unit(sc->sc_dev);
 224         kprintf("devfs: Please check that only the right ucom devices were removed!!!\n");
 225         dev_ops_remove_minor(&ucom_ops, /*UCOMUNIT_MASK, */unit);
 226
 227         return (0);
 228 }
 229
 230 static void
 231 ucom_shutdown(struct ucom_softc *sc)
 232 {
 233         struct tty *tp = sc->sc_tty;
 234
 235         DPRINTF(("ucom_shutdown\n"));
 236         /*
 237          * Hang up if necessary.  Wait a bit, so the other side has time to
 238          * notice even if we immediately open the port again.
 239          */
 240         if (ISSET(tp->t_cflag, HUPCL)) {
 241                 (void)ucomctl(sc, TIOCM_DTR, DMBIC);
 242                 (void)tsleep(sc, 0, "ucomsd", hz);
 243         }
 244 }
 245
 246 static int
 247 ucomopen(struct dev_open_args *ap)
 248 {
 249         cdev_t dev = ap->a_head.a_dev;
 250         int unit = UCOMUNIT(dev);
 251         struct ucom_softc *sc;
 252         usbd_status err;
 253         struct tty *tp;
 254         int error;
 255
 256         sc = devclass_get_softc(ucom_devclass, unit);
 257         if (sc == NULL)
 258                 return (ENXIO);
 259
 260         if (sc->sc_dying)
 261                 return (ENXIO);
 262
 263         tp = sc->sc_tty;
 264
 265         DPRINTF(("%s: ucomopen: tp = %p\n", device_get_nameunit(sc->sc_dev), tp));
 266
 267         if (ISSET(tp->t_state, TS_ISOPEN) &&
 268             ISSET(tp->t_state, TS_XCLUDE) &&
 269             priv_check_cred(ap->a_cred, PRIV_ROOT, 0)
 270         ) {
 271                 return (EBUSY);
 272         }
 273
 274         /*
 275          * Do the following iff this is a first open.
 276          */
 277         crit_enter();
 278         while (sc->sc_opening)
 279                 tsleep(&sc->sc_opening, 0, "ucomop", 0);
 280         sc->sc_opening = 1;
 281
 282         if (!ISSET(tp->t_state, TS_ISOPEN)) {
 283                 struct termios t;
 284
 285                 sc->sc_poll = 0;
 286                 sc->sc_lsr = sc->sc_msr = sc->sc_mcr = 0;
 287
 288                 tp->t_dev = reference_dev(dev);
 289
 290                 /*
 291                  * Initialize the termios status to the defaults.  Add in the
 292                  * sticky bits from TIOCSFLAGS.
 293                  */
 294                 t.c_ispeed = 0;
 295                 t.c_ospeed = TTYDEF_SPEED;
 296                 t.c_cflag = TTYDEF_CFLAG;
 297                 /* Make sure ucomparam() will do something. */
 298                 tp->t_ospeed = 0;
 299                 (void)ucomparam(tp, &t);
 300                 tp->t_iflag = TTYDEF_IFLAG;
 301                 tp->t_oflag = TTYDEF_OFLAG;
 302                 tp->t_lflag = TTYDEF_LFLAG;
 303                 ttychars(tp);
 304                 ttsetwater(tp);
 305
 306                 /*
 307                  * Turn on DTR.  We must always do this, even if carrier is not
 308                  * present, because otherwise we'd have to use TIOCSDTR
 309                  * immediately after setting CLOCAL, which applications do not
 310                  * expect.  We always assert DTR while the device is open
 311                  * unless explicitly requested to deassert it.
 312                  */
 313                 (void)ucomctl(sc, TIOCM_DTR | TIOCM_RTS, DMBIS);
 314
 315                 /* Device specific open */
 316                 if (sc->sc_callback->ucom_open != NULL) {
 317                         error = sc->sc_callback->ucom_open(sc->sc_parent,
 318                                                            sc->sc_portno);
 319                         if (error) {
 320                                 ucom_cleanup(sc);
 321                                 sc->sc_opening = 0;
 322                                 wakeup(&sc->sc_opening);
 323                                 crit_exit();
 324                                 return (error);
 325                         }
 326                 }
 327
 328                 DPRINTF(("ucomopen: open pipes in = %d out = %d\n",
 329                          sc->sc_bulkin_no, sc->sc_bulkout_no));
 330
 331                 /* Open the bulk pipes */
 332                 /* Bulk-in pipe */
 333                 err = usbd_open_pipe(sc->sc_iface, sc->sc_bulkin_no, 0,
 334                                      &sc->sc_bulkin_pipe);
 335                 if (err) {
 336                         kprintf("%s: open bulk in error (addr %d): %s\n",
 337                                device_get_nameunit(sc->sc_dev), sc->sc_bulkin_no,
 338                                usbd_errstr(err));
 339                         error = EIO;
 340                         goto fail_0;
 341                 }
 342                 /* Bulk-out pipe */
 343                 err = usbd_open_pipe(sc->sc_iface, sc->sc_bulkout_no,
 344                                      USBD_EXCLUSIVE_USE, &sc->sc_bulkout_pipe);
 345                 if (err) {
 346                         kprintf("%s: open bulk out error (addr %d): %s\n",
 347                                device_get_nameunit(sc->sc_dev), sc->sc_bulkout_no,
 348                                usbd_errstr(err));
 349                         error = EIO;
 350                         goto fail_1;
 351                 }
 352
 353                 /* Allocate a request and an input buffer and start reading. */
 354                 sc->sc_ixfer = usbd_alloc_xfer(sc->sc_udev);
 355                 if (sc->sc_ixfer == NULL) {
 356                         error = ENOMEM;
 357                         goto fail_2;
 358                 }
 359
 360                 sc->sc_ibuf = usbd_alloc_buffer(sc->sc_ixfer,
 361                                                 sc->sc_ibufsizepad);
 362                 if (sc->sc_ibuf == NULL) {
 363                         error = ENOMEM;
 364                         goto fail_3;
 365                 }
 366
 367                 sc->sc_oxfer = usbd_alloc_xfer(sc->sc_udev);
 368                 if (sc->sc_oxfer == NULL) {
 369                         error = ENOMEM;
 370                         goto fail_3;
 371                 }
 372
 373                 sc->sc_obuf = usbd_alloc_buffer(sc->sc_oxfer,
 374                                                 sc->sc_obufsize +
 375                                                 sc->sc_opkthdrlen);
 376                 if (sc->sc_obuf == NULL) {
 377                         error = ENOMEM;
 378                         goto fail_4;
 379                 }
 380
 381                 /*
 382                  * Handle initial DCD.
 383                  */
 384                 if (ISSET(sc->sc_msr, UMSR_DCD) ||
 385                     (minor(dev) & UCOM_CALLOUT_MASK))
 386                         (*linesw[tp->t_line].l_modem)(tp, 1);
 387
 388                 ucomstartread(sc);
 389         }
 390
 391         sc->sc_opening = 0;
 392         wakeup(&sc->sc_opening);
 393         crit_exit();
 394
 395         error = ttyopen(dev, tp);
 396         if (error)
 397                 goto bad;
 398
 399         error = (*linesw[tp->t_line].l_open)(dev, tp);
 400         if (error)
 401                 goto bad;
 402
 403         disc_optim(tp, &tp->t_termios, sc);
 404
 405         DPRINTF(("%s: ucomopen: success\n", device_get_nameunit(sc->sc_dev)));
 406
 407         sc->sc_poll = 1;
 408         sc->sc_refcnt++;
 409
 410         return (0);
 411
 412 fail_4:
 413         usbd_free_xfer(sc->sc_oxfer);
 414         sc->sc_oxfer = NULL;
 415 fail_3:
 416         usbd_free_xfer(sc->sc_ixfer);
 417         sc->sc_ixfer = NULL;
 418 fail_2:
 419         usbd_close_pipe(sc->sc_bulkout_pipe);
 420         sc->sc_bulkout_pipe = NULL;
 421 fail_1:
 422         usbd_close_pipe(sc->sc_bulkin_pipe);
 423         sc->sc_bulkin_pipe = NULL;
 424 fail_0:
 425         sc->sc_opening = 0;
 426         wakeup(&sc->sc_opening);
 427         crit_exit();
 428         return (error);
 429
 430 bad:
 431         if (!ISSET(tp->t_state, TS_ISOPEN)) {
 432                 /*
 433                  * We failed to open the device, and nobody else had it opened.
 434                  * Clean up the state as appropriate.
 435                  */
 436                 ucom_cleanup(sc);
 437         }
 438
 439         DPRINTF(("%s: ucomopen: failed\n", device_get_nameunit(sc->sc_dev)));
 440
 441         return (error);
 442 }
 443
 444 static int
 445 ucomclose(struct dev_close_args *ap)
 446 {
 447         cdev_t dev = ap->a_head.a_dev;
 448         struct ucom_softc *sc;
 449         struct tty *tp;
 450
 451         sc = devclass_get_softc(ucom_devclass, UCOMUNIT(dev));
 452
 453         tp = sc->sc_tty;
 454
 455         DPRINTF(("%s: ucomclose: unit = %d\n",
 456                 device_get_nameunit(sc->sc_dev), UCOMUNIT(dev)));
 457
 458         if (!ISSET(tp->t_state, TS_ISOPEN))
 459                 goto quit;
 460
 461         crit_enter();
 462         (*linesw[tp->t_line].l_close)(tp, ap->a_fflag);
 463         disc_optim(tp, &tp->t_termios, sc);
 464         ttyclose(tp);
 465         crit_exit();
 466
 467         if (sc->sc_dying)
 468                 goto quit;
 469
 470         if (!ISSET(tp->t_state, TS_ISOPEN)) {
 471                 /*
 472                  * Although we got a last close, the device may still be in
 473                  * use; e.g. if this was the dialout node, and there are still
 474                  * processes waiting for carrier on the non-dialout node.
 475                  */
 476                 ucom_cleanup(sc);
 477         }
 478
 479         if (sc->sc_callback->ucom_close != NULL)
 480                 sc->sc_callback->ucom_close(sc->sc_parent, sc->sc_portno);
 481
 482 quit:
 483         if (tp->t_dev) {
 484                 release_dev(tp->t_dev);
 485                 tp->t_dev = NULL;
 486         }
 487
 488         if (--sc->sc_refcnt < 0)
 489                 usb_detach_wakeup(sc->sc_dev);
 490
 491         return (0);
 492 }
 493
 494 static int
 495 ucomread(struct dev_read_args *ap)
 496 {
 497         cdev_t dev = ap->a_head.a_dev;
 498         struct ucom_softc *sc;
 499         struct tty *tp;
 500         int error;
 501
 502         sc = devclass_get_softc(ucom_devclass, UCOMUNIT(dev));
 503         tp = sc->sc_tty;
 504
 505         DPRINTF(("ucomread: tp = %p, flag = 0x%x\n", tp, ap->a_ioflag));
 506
 507         if (sc->sc_dying)
 508                 return (EIO);
 509
 510         error = (*linesw[tp->t_line].l_read)(tp, ap->a_uio, ap->a_ioflag);
 511
 512         DPRINTF(("ucomread: error = %d\n", error));
 513
 514         return (error);
 515 }
 516
 517 static int
 518 ucomwrite(struct dev_write_args *ap)
 519 {
 520         cdev_t dev = ap->a_head.a_dev;
 521         struct ucom_softc *sc;
 522         struct tty *tp;
 523         int error;
 524
 525         sc = devclass_get_softc(ucom_devclass, UCOMUNIT(dev));
 526         tp = sc->sc_tty;
 527
 528         DPRINTF(("ucomwrite: tp = %p, flag = 0x%x\n", tp, ap->a_ioflag));
 529
 530         if (sc->sc_dying)
 531                 return (EIO);
 532
 533         error = (*linesw[tp->t_line].l_write)(tp, ap->a_uio, ap->a_ioflag);
 534
 535         DPRINTF(("ucomwrite: error = %d\n", error));
 536
 537         return (error);
 538 }
 539
 540 static int
 541 ucomioctl(struct dev_ioctl_args *ap)
 542 {
 543         cdev_t dev = ap->a_head.a_dev;
 544         struct ucom_softc *sc;
 545         struct tty *tp;
 546         int error;
 547         int d;
 548
 549         sc = devclass_get_softc(ucom_devclass, UCOMUNIT(dev));
 550         tp = sc->sc_tty;
 551
 552         if (sc->sc_dying)
 553                 return (EIO);
 554
 555         DPRINTF(("ucomioctl: cmd = 0x%08lx\n", ap->a_cmd));
 556
 557         error = (*linesw[tp->t_line].l_ioctl)(tp, ap->a_cmd, ap->a_data,
 558                                               ap->a_fflag, ap->a_cred);
 559         if (error != ENOIOCTL) {
 560                 DPRINTF(("ucomioctl: l_ioctl: error = %d\n", error));
 561                 return (error);
 562         }
 563
 564         crit_enter();
 565
 566         error = ttioctl(tp, ap->a_cmd, ap->a_data, ap->a_fflag);
 567         disc_optim(tp, &tp->t_termios, sc);
 568         if (error != ENOIOCTL) {
 569                 crit_exit();
 570                 DPRINTF(("ucomioctl: ttioctl: error = %d\n", error));
 571                 return (error);
 572         }
 573
 574         if (sc->sc_callback->ucom_ioctl != NULL) {
 575                 error = sc->sc_callback->ucom_ioctl(sc->sc_parent,
 576                                                     sc->sc_portno,
 577                                                     ap->a_cmd, ap->a_data,
 578                                                     ap->a_fflag, curthread);
 579                 if (error >= 0) {
 580                         crit_exit();
 581                         return (error);
 582                 }
 583         }
 584
 585         error = 0;
 586
 587         DPRINTF(("ucomioctl: our cmd = 0x%08lx\n", ap->a_cmd));
 588
 589         switch (ap->a_cmd) {
 590         case TIOCSBRK:
 591                 DPRINTF(("ucomioctl: TIOCSBRK\n"));
 592                 ucom_break(sc, 1);
 593                 break;
 594         case TIOCCBRK:
 595                 DPRINTF(("ucomioctl: TIOCCBRK\n"));
 596                 ucom_break(sc, 0);
 597                 break;
 598
 599         case TIOCSDTR:
 600                 DPRINTF(("ucomioctl: TIOCSDTR\n"));
 601                 (void)ucomctl(sc, TIOCM_DTR, DMBIS);
 602                 break;
 603         case TIOCCDTR:
 604                 DPRINTF(("ucomioctl: TIOCCDTR\n"));
 605                 (void)ucomctl(sc, TIOCM_DTR, DMBIC);
 606                 break;
 607
 608         case TIOCMSET:
 609                 d = *(int *)ap->a_data;
 610                 DPRINTF(("ucomioctl: TIOCMSET, 0x%x\n", d));
 611                 (void)ucomctl(sc, d, DMSET);
 612                 break;
 613         case TIOCMBIS:
 614                 d = *(int *)ap->a_data;
 615                 DPRINTF(("ucomioctl: TIOCMBIS, 0x%x\n", d));
 616                 (void)ucomctl(sc, d, DMBIS);
 617                 break;
 618         case TIOCMBIC:
 619                 d = *(int *)ap->a_data;
 620                 DPRINTF(("ucomioctl: TIOCMBIC, 0x%x\n", d));
 621                 (void)ucomctl(sc, d, DMBIC);
 622                 break;
 623         case TIOCMGET:
 624                 d = ucomctl(sc, 0, DMGET);
 625                 DPRINTF(("ucomioctl: TIOCMGET, 0x%x\n", d));
 626                 *(int *)ap->a_data = d;
 627                 break;
 628
 629         default:
 630                 DPRINTF(("ucomioctl: error: our cmd = 0x%08lx\n", ap->a_cmd));
 631                 error = ENOTTY;
 632                 break;
 633         }
 634
 635         crit_exit();
 636
 637         return (error);
 638 }
 639
 640 static int
 641 ucomctl(struct ucom_softc *sc, int bits, int how)
 642 {
 643         int     mcr;
 644         int     msr;
 645         int     onoff;
 646
 647         DPRINTF(("ucomctl: bits = 0x%x, how = %d\n", bits, how));
 648
 649         if (how == DMGET) {
 650                 SET(bits, TIOCM_LE);            /* always set TIOCM_LE bit */
 651                 DPRINTF(("ucomctl: DMGET: LE"));
 652
 653                 mcr = sc->sc_mcr;
 654                 if (ISSET(mcr, UMCR_DTR)) {
 655                         SET(bits, TIOCM_DTR);
 656                         DPRINTF((" DTR"));
 657                 }
 658                 if (ISSET(mcr, UMCR_RTS)) {
 659                         SET(bits, TIOCM_RTS);
 660                         DPRINTF((" RTS"));
 661                 }
 662
 663                 msr = sc->sc_msr;
 664                 if (ISSET(msr, UMSR_CTS)) {
 665                         SET(bits, TIOCM_CTS);
 666                         DPRINTF((" CTS"));
 667                 }
 668                 if (ISSET(msr, UMSR_DCD)) {
 669                         SET(bits, TIOCM_CD);
 670                         DPRINTF((" CD"));
 671                 }
 672                 if (ISSET(msr, UMSR_DSR)) {
 673                         SET(bits, TIOCM_DSR);
 674                         DPRINTF((" DSR"));
 675                 }
 676                 if (ISSET(msr, UMSR_RI)) {
 677                         SET(bits, TIOCM_RI);
 678                         DPRINTF((" RI"));
 679                 }
 680
 681                 DPRINTF(("\n"));
 682
 683                 return (bits);
 684         }
 685
 686         mcr = 0;
 687         if (ISSET(bits, TIOCM_DTR))
 688                 SET(mcr, UMCR_DTR);
 689         if (ISSET(bits, TIOCM_RTS))
 690                 SET(mcr, UMCR_RTS);
 691
 692         switch (how) {
 693         case DMSET:
 694                 sc->sc_mcr = mcr;
 695                 break;
 696         case DMBIS:
 697                 sc->sc_mcr |= mcr;
 698                 break;
 699         case DMBIC:
 700                 sc->sc_mcr &= ~mcr;
 701                 break;
 702         }
 703
 704         onoff = ISSET(sc->sc_mcr, UMCR_DTR) ? 1 : 0;
 705         ucom_dtr(sc, onoff);
 706
 707         onoff = ISSET(sc->sc_mcr, UMCR_RTS) ? 1 : 0;
 708         ucom_rts(sc, onoff);
 709
 710         return (0);
 711 }
 712
 713 static void
 714 ucom_break(struct ucom_softc *sc, int onoff)
 715 {
 716         DPRINTF(("ucom_break: onoff = %d\n", onoff));
 717
 718         if (sc->sc_callback->ucom_set == NULL)
 719                 return;
 720         sc->sc_callback->ucom_set(sc->sc_parent, sc->sc_portno,
 721                                   UCOM_SET_BREAK, onoff);
 722 }
 723
 724 static void
 725 ucom_dtr(struct ucom_softc *sc, int onoff)
 726 {
 727         DPRINTF(("ucom_dtr: 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_DTR, onoff);
 733 }
 734
 735 static void
 736 ucom_rts(struct ucom_softc *sc, int onoff)
 737 {
 738         DPRINTF(("ucom_rts: 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_RTS, onoff);
 744 }
 745
 746 void
 747 ucom_status_change(struct ucom_softc *sc)
 748 {
 749         struct tty *tp = sc->sc_tty;
 750         u_char old_msr;
 751         int onoff;
 752
 753         if (sc->sc_callback->ucom_get_status == NULL) {
 754                 sc->sc_lsr = 0;
 755                 sc->sc_msr = 0;
 756                 return;
 757         }
 758
 759         old_msr = sc->sc_msr;
 760         sc->sc_callback->ucom_get_status(sc->sc_parent, sc->sc_portno,
 761                                          &sc->sc_lsr, &sc->sc_msr);
 762         if (ISSET((sc->sc_msr ^ old_msr), UMSR_DCD)) {
 763                 if (sc->sc_poll == 0)
 764                         return;
 765                 onoff = ISSET(sc->sc_msr, UMSR_DCD) ? 1 : 0;
 766                 DPRINTF(("ucom_status_change: DCD changed to %d\n", onoff));
 767                 (*linesw[tp->t_line].l_modem)(tp, onoff);
 768         }
 769 }
 770
 771 static int
 772 ucomparam(struct tty *tp, struct termios *t)
 773 {
 774         struct ucom_softc *sc;
 775         int error;
 776         usbd_status uerr;
 777
 778         sc = devclass_get_softc(ucom_devclass, UCOMUNIT(tp->t_dev));
 779
 780         if (sc->sc_dying)
 781                 return (EIO);
 782
 783         DPRINTF(("ucomparam: sc = %p\n", sc));
 784
 785         /* Check requested parameters. */
 786         if (t->c_ospeed < 0) {
 787                 DPRINTF(("ucomparam: negative ospeed\n"));
 788                 return (EINVAL);
 789         }
 790         if (t->c_ispeed && t->c_ispeed != t->c_ospeed) {
 791                 DPRINTF(("ucomparam: mismatch ispeed and ospeed\n"));
 792                 return (EINVAL);
 793         }
 794
 795         /*
 796          * If there were no changes, don't do anything.  This avoids dropping
 797          * input and improves performance when all we did was frob things like
 798          * VMIN and VTIME.
 799          */
 800         if (tp->t_ospeed == t->c_ospeed &&
 801             tp->t_cflag == t->c_cflag)
 802                 return (0);
 803
 804         /* And copy to tty. */
 805         tp->t_ispeed = 0;
 806         tp->t_ospeed = t->c_ospeed;
 807         tp->t_cflag = t->c_cflag;
 808
 809         if (sc->sc_callback->ucom_param == NULL)
 810                 return (0);
 811
 812         ucomstopread(sc);
 813
 814         error = sc->sc_callback->ucom_param(sc->sc_parent, sc->sc_portno, t);
 815         if (error) {
 816                 DPRINTF(("ucomparam: callback: error = %d\n", error));
 817                 return (error);
 818         }
 819
 820         ttsetwater(tp);
 821
 822         if (t->c_cflag & CRTS_IFLOW) {
 823                 sc->sc_state |= UCS_RTS_IFLOW;
 824         } else if (sc->sc_state & UCS_RTS_IFLOW) {
 825                 sc->sc_state &= ~UCS_RTS_IFLOW;
 826                 (void)ucomctl(sc, UMCR_RTS, DMBIS);
 827         }
 828
 829         disc_optim(tp, t, sc);
 830
 831         uerr = ucomstartread(sc);
 832         if (uerr != USBD_NORMAL_COMPLETION)
 833                 return (EIO);
 834
 835         return (0);
 836 }
 837
 838 static void
 839 ucomstart(struct tty *tp)
 840 {
 841         struct ucom_softc *sc;
 842         struct cblock *cbp;
 843         usbd_status err;
 844         u_char *data;
 845         int cnt;
 846
 847         sc = devclass_get_softc(ucom_devclass, UCOMUNIT(tp->t_dev));
 848         DPRINTF(("ucomstart: sc = %p\n", sc));
 849
 850         if (sc->sc_dying)
 851                 return;
 852
 853         crit_enter();
 854
 855         if (tp->t_state & TS_TBLOCK) {
 856                 if (ISSET(sc->sc_mcr, UMCR_RTS) &&
 857                     ISSET(sc->sc_state, UCS_RTS_IFLOW)) {
 858                         DPRINTF(("ucomstart: clear RTS\n"));
 859                         (void)ucomctl(sc, UMCR_RTS, DMBIC);
 860                 }
 861         } else {
 862                 if (!ISSET(sc->sc_mcr, UMCR_RTS) &&
 863                     tp->t_rawq.c_cc <= tp->t_ilowat &&
 864                     ISSET(sc->sc_state, UCS_RTS_IFLOW)) {
 865                         DPRINTF(("ucomstart: set RTS\n"));
 866                         (void)ucomctl(sc, UMCR_RTS, DMBIS);
 867                 }
 868         }
 869
 870         if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP)) {
 871                 ttwwakeup(tp);
 872                 DPRINTF(("ucomstart: stopped\n"));
 873                 goto out;
 874         }
 875
 876         if (tp->t_outq.c_cc <= tp->t_olowat) {
 877                 if (ISSET(tp->t_state, TS_SO_OLOWAT)) {
 878                         CLR(tp->t_state, TS_SO_OLOWAT);
 879                         wakeup(TSA_OLOWAT(tp));
 880                 }
 881                 selwakeup(&tp->t_wsel);
 882                 if (tp->t_outq.c_cc == 0) {
 883                         if (ISSET(tp->t_state, TS_BUSY | TS_SO_OCOMPLETE) ==
 884                             TS_SO_OCOMPLETE && tp->t_outq.c_cc == 0) {
 885                                 CLR(tp->t_state, TS_SO_OCOMPLETE);
 886                                 wakeup(TSA_OCOMPLETE(tp));
 887                         }
 888                         goto out;
 889                 }
 890         }
 891
 892         /* Grab the first contiguous region of buffer space. */
 893         data = tp->t_outq.c_cf;
 894         cbp = (struct cblock *) ((intptr_t) tp->t_outq.c_cf & ~CROUND);
 895         cnt = min((char *) (cbp+1) - tp->t_outq.c_cf, tp->t_outq.c_cc);
 896
 897         if (cnt == 0) {
 898                 DPRINTF(("ucomstart: cnt == 0\n"));
 899                 goto out;
 900         }
 901
 902         SET(tp->t_state, TS_BUSY);
 903
 904         if (cnt > sc->sc_obufsize) {
 905                 DPRINTF(("ucomstart: big buffer %d chars\n", cnt));
 906                 cnt = sc->sc_obufsize;
 907         }
 908         if (sc->sc_callback->ucom_write != NULL)
 909                 sc->sc_callback->ucom_write(sc->sc_parent, sc->sc_portno,
 910                                             sc->sc_obuf, data, &cnt);
 911         else
 912                 memcpy(sc->sc_obuf, data, cnt);
 913
 914         DPRINTF(("ucomstart: %d chars\n", cnt));
 915         usbd_setup_xfer(sc->sc_oxfer, sc->sc_bulkout_pipe,
 916                         (usbd_private_handle)sc, sc->sc_obuf, cnt,
 917                         USBD_NO_COPY, USBD_NO_TIMEOUT, ucomwritecb);
 918         /* What can we do on error? */
 919         err = usbd_transfer(sc->sc_oxfer);
 920         if (err != USBD_IN_PROGRESS)
 921                 kprintf("ucomstart: err=%s\n", usbd_errstr(err));
 922
 923         ttwwakeup(tp);
 924
 925     out:
 926         crit_exit();
 927 }
 928
 929 static void
 930 ucomstop(struct tty *tp, int flag)
 931 {
 932         struct ucom_softc *sc;
 933
 934         sc = devclass_get_softc(ucom_devclass, UCOMUNIT(tp->t_dev));
 935
 936         DPRINTF(("ucomstop: %d\n", flag));
 937
 938         if (flag & FREAD) {
 939                 /*
 940                  * This is just supposed to flush pending receive data,
 941                  * not stop the reception of data entirely!
 942                  */
 943                 DPRINTF(("ucomstop: read\n"));
 944                 ucomstopread(sc);
 945                 ucomstartread(sc);
 946         }
 947
 948         if (flag & FWRITE) {
 949                 DPRINTF(("ucomstop: write\n"));
 950                 crit_enter();
 951                 if (ISSET(tp->t_state, TS_BUSY)) {
 952                         /* XXX do what? */
 953                         if (!ISSET(tp->t_state, TS_TTSTOP))
 954                                 SET(tp->t_state, TS_FLUSH);
 955                 }
 956                 crit_exit();
 957         }
 958
 959         DPRINTF(("ucomstop: done\n"));
 960 }
 961
 962 static void
 963 ucomwritecb(usbd_xfer_handle xfer, usbd_private_handle p, usbd_status status)
 964 {
 965         struct ucom_softc *sc = (struct ucom_softc *)p;
 966         struct tty *tp = sc->sc_tty;
 967         u_int32_t cc;
 968
 969         DPRINTF(("ucomwritecb: status = %d\n", status));
 970
 971         if (status == USBD_CANCELLED || sc->sc_dying)
 972                 goto error;
 973
 974         if (status != USBD_NORMAL_COMPLETION) {
 975                 kprintf("%s: ucomwritecb: %s\n",
 976                        device_get_nameunit(sc->sc_dev), usbd_errstr(status));
 977                 if (status == USBD_STALLED)
 978                         usbd_clear_endpoint_stall_async(sc->sc_bulkin_pipe);
 979                 /*
 980                  * XXX.  We may need a flag to sequence ucomstopread() and
 981                  * ucomstartread() to handle the case where ucomstartread()
 982                  * is called after ucomstopread() but before the request has
 983                  * been properly canceled?
 984                  */
 985                 goto error;
 986         }
 987
 988         usbd_get_xfer_status(xfer, NULL, NULL, &cc, NULL);
 989         DPRINTF(("ucomwritecb: cc = %d\n", cc));
 990         if (cc <= sc->sc_opkthdrlen) {
 991                 kprintf("%s: sent size too small, cc = %d\n",
 992                         device_get_nameunit(sc->sc_dev), cc);
 993                 goto error;
 994         }
 995
 996         /* convert from USB bytes to tty bytes */
 997         cc -= sc->sc_opkthdrlen;
 998
 999         crit_enter();
1000         CLR(tp->t_state, TS_BUSY);
1001         if (ISSET(tp->t_state, TS_FLUSH))
1002                 CLR(tp->t_state, TS_FLUSH);
1003         else
1004                 ndflush(&tp->t_outq, cc);
1005         (*linesw[tp->t_line].l_start)(tp);
1006         crit_exit();
1007
1008         return;
1009
1010   error:
1011         crit_enter();
1012         CLR(tp->t_state, TS_BUSY);
1013         crit_exit();
1014         return;
1015 }
1016
1017 static usbd_status
1018 ucomstartread(struct ucom_softc *sc)
1019 {
1020         usbd_status err;
1021
1022         DPRINTF(("ucomstartread: start\n"));
1023
1024         sc->sc_state &= ~UCS_RXSTOP;
1025
1026         if (sc->sc_bulkin_pipe == NULL)
1027                 return (USBD_NORMAL_COMPLETION);
1028
1029         usbd_setup_xfer(sc->sc_ixfer, sc->sc_bulkin_pipe,
1030                         (usbd_private_handle)sc,
1031                         sc->sc_ibuf, sc->sc_ibufsize,
1032                         USBD_SHORT_XFER_OK | USBD_NO_COPY,
1033                         USBD_NO_TIMEOUT, ucomreadcb);
1034
1035         err = usbd_transfer(sc->sc_ixfer);
1036         if (err != USBD_IN_PROGRESS) {
1037                 DPRINTF(("ucomstartread: err = %s\n", usbd_errstr(err)));
1038                 return (err);
1039         }
1040
1041         return (USBD_NORMAL_COMPLETION);
1042 }
1043
1044 static void
1045 ucomreadcb(usbd_xfer_handle xfer, usbd_private_handle p, usbd_status status)
1046 {
1047         struct ucom_softc *sc = (struct ucom_softc *)p;
1048         struct tty *tp = sc->sc_tty;
1049         int (*rint) (int c, struct tty *tp) = linesw[tp->t_line].l_rint;
1050         usbd_status err;
1051         u_int32_t cc;
1052         u_char *cp;
1053         int lostcc;
1054
1055         DPRINTF(("ucomreadcb: status = %d\n", status));
1056
1057         if (status != USBD_NORMAL_COMPLETION) {
1058                 if (!(sc->sc_state & UCS_RXSTOP))
1059                         kprintf("%s: ucomreadcb: %s\n",
1060                                device_get_nameunit(sc->sc_dev), usbd_errstr(status));
1061                 if (status == USBD_STALLED)
1062                         usbd_clear_endpoint_stall_async(sc->sc_bulkin_pipe);
1063                 /* XXX we should restart after some delay. */
1064                 return;
1065         }
1066
1067         usbd_get_xfer_status(xfer, NULL, (void **)&cp, &cc, NULL);
1068         DPRINTF(("ucomreadcb: got %d chars, tp = %p\n", cc, tp));
1069         if (cc == 0)
1070                 goto resubmit;
1071
1072         if (sc->sc_callback->ucom_read != NULL) {
1073                 sc->sc_callback->ucom_read(sc->sc_parent, sc->sc_portno,
1074                                            &cp, &cc);
1075         }
1076
1077         if (cc > sc->sc_ibufsize) {
1078                 kprintf("%s: invalid receive data size, %d chars\n",
1079                         device_get_nameunit(sc->sc_dev), cc);
1080                 goto resubmit;
1081         }
1082         if (cc < 1)
1083                 goto resubmit;
1084
1085         crit_enter();
1086         if (tp->t_state & TS_CAN_BYPASS_L_RINT) {
1087                 if (tp->t_rawq.c_cc + cc > tp->t_ihiwat
1088                     && (sc->sc_state & UCS_RTS_IFLOW
1089                         || tp->t_iflag & IXOFF)
1090                     && !(tp->t_state & TS_TBLOCK))
1091                         ttyblock(tp);
1092                 lostcc = b_to_q((char *)cp, cc, &tp->t_rawq);
1093                 tp->t_rawcc += cc;
1094                 if (sc->hotchar) {
1095                         while (cc) {
1096                                 if (*cp == sc->hotchar)
1097                                         break;
1098                                 --cc;
1099                                 ++cp;
1100                         }
1101                         if (cc)
1102                                 setsofttty();
1103                 }
1104                 ttwakeup(tp);
1105                 if (tp->t_state & TS_TTSTOP
1106                     && (tp->t_iflag & IXANY
1107                         || tp->t_cc[VSTART] == tp->t_cc[VSTOP])) {
1108                         tp->t_state &= ~TS_TTSTOP;
1109                         tp->t_lflag &= ~FLUSHO;
1110                         ucomstart(tp);
1111                 }
1112                 if (lostcc > 0)
1113                         kprintf("%s: lost %d chars\n", device_get_nameunit(sc->sc_dev),
1114                                lostcc);
1115         } else {
1116                 /* Give characters to tty layer. */
1117                 while (cc > 0) {
1118                         DPRINTFN(7, ("ucomreadcb: char = 0x%02x\n", *cp));
1119                         if ((*rint)(*cp, tp) == -1) {
1120                                 /* XXX what should we do? */
1121                                 kprintf("%s: lost %d chars\n",
1122                                        device_get_nameunit(sc->sc_dev), cc);
1123                                 break;
1124                         }
1125                         cc--;
1126                         cp++;
1127                 }
1128         }
1129         crit_exit();
1130
1131 resubmit:
1132         err = ucomstartread(sc);
1133         if (err) {
1134                 kprintf("%s: read start failed\n", device_get_nameunit(sc->sc_dev));
1135                 /* XXX what should we dow now? */
1136         }
1137
1138         if ((sc->sc_state & UCS_RTS_IFLOW) && !ISSET(sc->sc_mcr, UMCR_RTS)
1139             && !(tp->t_state & TS_TBLOCK))
1140                 ucomctl(sc, UMCR_RTS, DMBIS);
1141 }
1142
1143 static void
1144 ucom_cleanup(struct ucom_softc *sc)
1145 {
1146         DPRINTF(("ucom_cleanup: closing pipes\n"));
1147
1148         ucom_shutdown(sc);
1149         if (sc->sc_bulkin_pipe != NULL) {
1150                 usbd_abort_pipe(sc->sc_bulkin_pipe);
1151                 usbd_close_pipe(sc->sc_bulkin_pipe);
1152                 sc->sc_bulkin_pipe = NULL;
1153         }
1154         if (sc->sc_bulkout_pipe != NULL) {
1155                 usbd_abort_pipe(sc->sc_bulkout_pipe);
1156                 usbd_close_pipe(sc->sc_bulkout_pipe);
1157                 sc->sc_bulkout_pipe = NULL;
1158         }
1159         if (sc->sc_ixfer != NULL) {
1160                 usbd_free_xfer(sc->sc_ixfer);
1161                 sc->sc_ixfer = NULL;
1162         }
1163         if (sc->sc_oxfer != NULL) {
1164                 usbd_free_xfer(sc->sc_oxfer);
1165                 sc->sc_oxfer = NULL;
1166         }
1167 }
1168
1169 static void
1170 ucomstopread(struct ucom_softc *sc)
1171 {
1172         usbd_status err;
1173
1174         DPRINTF(("ucomstopread: enter\n"));
1175
1176         if (!(sc->sc_state & UCS_RXSTOP)) {
1177                 sc->sc_state |= UCS_RXSTOP;
1178                 if (sc->sc_bulkin_pipe == NULL) {
1179                         DPRINTF(("ucomstopread: bulkin pipe NULL\n"));
1180                         return;
1181                 }
1182                 err = usbd_abort_pipe(sc->sc_bulkin_pipe);
1183                 if (err) {
1184                         DPRINTF(("ucomstopread: err = %s\n",
1185                                  usbd_errstr(err)));
1186                 }
1187         }
1188
1189         DPRINTF(("ucomstopread: leave\n"));
1190 }
1191
1192 static void
1193 disc_optim(struct tty *tp, struct termios *t, struct ucom_softc *sc)
1194 {
1195         if (!(t->c_iflag & (ICRNL | IGNCR | IMAXBEL | INLCR | ISTRIP | IXON))
1196             && (!(t->c_iflag & BRKINT) || (t->c_iflag & IGNBRK))
1197             && (!(t->c_iflag & PARMRK)
1198                 || (t->c_iflag & (IGNPAR | IGNBRK)) == (IGNPAR | IGNBRK))
1199             && !(t->c_lflag & (ECHO | ICANON | IEXTEN | ISIG | PENDIN))
1200             && linesw[tp->t_line].l_rint == ttyinput) {
1201                 DPRINTF(("disc_optim: bypass l_rint\n"));
1202                 tp->t_state |= TS_CAN_BYPASS_L_RINT;
1203         } else {
1204                 DPRINTF(("disc_optim: can't bypass l_rint\n"));
1205                 tp->t_state &= ~TS_CAN_BYPASS_L_RINT;
1206         }
1207         sc->hotchar = linesw[tp->t_line].l_hotchar;
1208 }