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 1.27 2007/07/02 06:43:31 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/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 #include <sys/select.h>
  82 #include <sys/proc.h>
  83 #include <sys/vnode.h>
  84 #include <sys/poll.h>
  85 #include <sys/sysctl.h>
  86 #include <sys/thread2.h>
  87
  88 #include <bus/usb/usb.h>
  89 #include <bus/usb/usbcdc.h>
  90
  91 #include <bus/usb/usbdi.h>
  92 #include <bus/usb/usbdi_util.h>
  93 #include <bus/usb/usbdevs.h>
  94 #include <bus/usb/usb_quirks.h>
  95
  96 #include "ucomvar.h"
  97
  98 #ifdef USB_DEBUG
  99 static int      ucomdebug = 0;
 100 SYSCTL_NODE(_hw_usb, OID_AUTO, ucom, CTLFLAG_RW, 0, "USB ucom");
 101 SYSCTL_INT(_hw_usb_ucom, OID_AUTO, debug, CTLFLAG_RW,
 102            &ucomdebug, 0, "ucom debug level");
 103 #define DPRINTF(x)      do { \
 104                                 if (ucomdebug) \
 105                                         kprintf x; \
 106                         } while (0)
 107
 108 #define DPRINTFN(n, x)  do { \
 109                                 if (ucomdebug > (n)) \
 110                                         kprintf x; \
 111                         } while (0)
 112 #else
 113 #define DPRINTF(x)
 114 #define DPRINTFN(n, x)
 115 #endif
 116
 117 static d_open_t  ucomopen;
 118 static d_close_t ucomclose;
 119 static d_read_t  ucomread;
 120 static d_write_t ucomwrite;
 121 static d_ioctl_t ucomioctl;
 122
 123 #define UCOM_CDEV_MAJOR  138
 124
 125 static struct dev_ops ucom_ops = {
 126         { "ucom", UCOM_CDEV_MAJOR, D_TTY | D_KQFILTER },
 127         .d_open =       ucomopen,
 128         .d_close =      ucomclose,
 129         .d_read =       ucomread,
 130         .d_write =      ucomwrite,
 131         .d_ioctl =      ucomioctl,
 132         .d_poll =       ttypoll,
 133         .d_kqfilter =   ttykqfilter
 134 };
 135
 136 static void ucom_cleanup(struct ucom_softc *);
 137 static int ucomctl(struct ucom_softc *, int, int);
 138 static int ucomparam(struct tty *, struct termios *);
 139 static void ucomstart(struct tty *);
 140 static void ucomstop(struct tty *, int);
 141 static void ucom_shutdown(struct ucom_softc *);
 142 static void ucom_dtr(struct ucom_softc *, int);
 143 static void ucom_rts(struct ucom_softc *, int);
 144 static void ucom_break(struct ucom_softc *, int);
 145 static usbd_status ucomstartread(struct ucom_softc *);
 146 static void ucomreadcb(usbd_xfer_handle, usbd_private_handle, usbd_status);
 147 static void ucomwritecb(usbd_xfer_handle, usbd_private_handle, usbd_status);
 148 static void ucomstopread(struct ucom_softc *);
 149 static void disc_optim(struct tty *, struct termios *, struct ucom_softc *);
 150
 151 devclass_t ucom_devclass;
 152
 153 static moduledata_t ucom_mod = {
 154         "ucom",
 155         NULL,
 156         NULL
 157 };
 158
 159 DECLARE_MODULE(ucom, ucom_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE);
 160 MODULE_DEPEND(ucom, usb, 1, 1, 1);
 161 MODULE_VERSION(ucom, UCOM_MODVER);
 162
 163 int
 164 ucom_attach(struct ucom_softc *sc)
 165 {
 166         struct tty *tp;
 167         int unit;
 168         cdev_t dev;
 169
 170         unit = device_get_unit(sc->sc_dev);
 171
 172         sc->sc_tty = tp = ttymalloc(sc->sc_tty);
 173         tp->t_oproc = ucomstart;
 174         tp->t_param = ucomparam;
 175         tp->t_stop = ucomstop;
 176
 177         DPRINTF(("ucom_attach: tty_attach tp = %p\n", tp));
 178
 179         DPRINTF(("ucom_attach: make_dev: ucom%d\n", unit));
 180
 181         dev_ops_add(&ucom_ops, UCOMUNIT_MASK, unit);
 182         dev = make_dev(&ucom_ops, unit | UCOM_CALLOUT_MASK,
 183                         UID_UUCP, GID_DIALER, 0660,
 184                         "ucom%d", unit);
 185         dev->si_tty = tp;
 186
 187         return (0);
 188 }
 189
 190 int
 191 ucom_detach(struct ucom_softc *sc)
 192 {
 193         struct tty *tp = sc->sc_tty;
 194         int unit;
 195
 196         DPRINTF(("ucom_detach: sc = %p, tp = %p\n", sc, sc->sc_tty));
 197
 198         sc->sc_dying = 1;
 199
 200         if (sc->sc_bulkin_pipe != NULL)
 201                 usbd_abort_pipe(sc->sc_bulkin_pipe);
 202         if (sc->sc_bulkout_pipe != NULL)
 203                 usbd_abort_pipe(sc->sc_bulkout_pipe);
 204
 205         if (tp != NULL) {
 206                 if (tp->t_state & TS_ISOPEN) {
 207                         device_printf(sc->sc_dev,
 208                                       "still open, forcing close\n");
 209                         (*linesw[tp->t_line].l_close)(tp, 0);
 210                         tp->t_gen++;
 211                         ttyclose(tp);
 212                         ttwakeup(tp);
 213                         ttwwakeup(tp);
 214                 }
 215         } else {
 216                 DPRINTF(("ucom_detach: no tty\n"));
 217                 return (0);
 218         }
 219
 220         crit_enter();
 221         if (--sc->sc_refcnt >= 0) {
 222                 /* Wait for processes to go away. */
 223                 usb_detach_wait(sc->sc_dev);
 224         }
 225         crit_exit();
 226
 227         unit = device_get_unit(sc->sc_dev);
 228         dev_ops_remove(&ucom_ops, UCOMUNIT_MASK, unit);
 229
 230         return (0);
 231 }
 232
 233 static void
 234 ucom_shutdown(struct ucom_softc *sc)
 235 {
 236         struct tty *tp = sc->sc_tty;
 237
 238         DPRINTF(("ucom_shutdown\n"));
 239         /*
 240          * Hang up if necessary.  Wait a bit, so the other side has time to
 241          * notice even if we immediately open the port again.
 242          */
 243         if (ISSET(tp->t_cflag, HUPCL)) {
 244                 (void)ucomctl(sc, TIOCM_DTR, DMBIC);
 245                 (void)tsleep(sc, 0, "ucomsd", hz);
 246         }
 247 }
 248
 249 static int
 250 ucomopen(struct dev_open_args *ap)
 251 {
 252         cdev_t dev = ap->a_head.a_dev;
 253         int unit = UCOMUNIT(dev);
 254         struct ucom_softc *sc;
 255         usbd_status err;
 256         struct tty *tp;
 257         int error;
 258
 259         sc = devclass_get_softc(ucom_devclass, unit);
 260         if (sc == NULL)
 261                 return (ENXIO);
 262
 263         if (sc->sc_dying)
 264                 return (ENXIO);
 265
 266         tp = sc->sc_tty;
 267
 268         DPRINTF(("%s: ucomopen: tp = %p\n", device_get_nameunit(sc->sc_dev), tp));
 269
 270         if (ISSET(tp->t_state, TS_ISOPEN) &&
 271             ISSET(tp->t_state, TS_XCLUDE) &&
 272             suser_cred(ap->a_cred, 0)
 273         ) {
 274                 return (EBUSY);
 275         }
 276
 277         /*
 278          * Do the following iff this is a first open.
 279          */
 280         crit_enter();
 281         while (sc->sc_opening)
 282                 tsleep(&sc->sc_opening, 0, "ucomop", 0);
 283         sc->sc_opening = 1;
 284
 285         if (!ISSET(tp->t_state, TS_ISOPEN)) {
 286                 struct termios t;
 287
 288                 sc->sc_poll = 0;
 289                 sc->sc_lsr = sc->sc_msr = sc->sc_mcr = 0;
 290
 291                 tp->t_dev = reference_dev(dev);
 292
 293                 /*
 294                  * Initialize the termios status to the defaults.  Add in the
 295                  * sticky bits from TIOCSFLAGS.
 296                  */
 297                 t.c_ispeed = 0;
 298                 t.c_ospeed = TTYDEF_SPEED;
 299                 t.c_cflag = TTYDEF_CFLAG;
 300                 /* Make sure ucomparam() will do something. */
 301                 tp->t_ospeed = 0;
 302                 (void)ucomparam(tp, &t);
 303                 tp->t_iflag = TTYDEF_IFLAG;
 304                 tp->t_oflag = TTYDEF_OFLAG;
 305                 tp->t_lflag = TTYDEF_LFLAG;
 306                 ttychars(tp);
 307                 ttsetwater(tp);
 308
 309                 /*
 310                  * Turn on DTR.  We must always do this, even if carrier is not
 311                  * present, because otherwise we'd have to use TIOCSDTR
 312                  * immediately after setting CLOCAL, which applications do not
 313                  * expect.  We always assert DTR while the device is open
 314                  * unless explicitly requested to deassert it.
 315                  */
 316                 (void)ucomctl(sc, TIOCM_DTR | TIOCM_RTS, DMBIS);
 317
 318                 /* Device specific open */
 319                 if (sc->sc_callback->ucom_open != NULL) {
 320                         error = sc->sc_callback->ucom_open(sc->sc_parent,
 321                                                            sc->sc_portno);
 322                         if (error) {
 323                                 ucom_cleanup(sc);
 324                                 sc->sc_opening = 0;
 325                                 wakeup(&sc->sc_opening);
 326                                 crit_exit();
 327                                 return (error);
 328                         }
 329                 }
 330
 331                 DPRINTF(("ucomopen: open pipes in = %d out = %d\n",
 332                          sc->sc_bulkin_no, sc->sc_bulkout_no));
 333
 334                 /* Open the bulk pipes */
 335                 /* Bulk-in pipe */
 336                 err = usbd_open_pipe(sc->sc_iface, sc->sc_bulkin_no, 0,
 337                                      &sc->sc_bulkin_pipe);
 338                 if (err) {
 339                         kprintf("%s: open bulk in error (addr %d): %s\n",
 340                                device_get_nameunit(sc->sc_dev), sc->sc_bulkin_no,
 341                                usbd_errstr(err));
 342                         error = EIO;
 343                         goto fail_0;
 344                 }
 345                 /* Bulk-out pipe */
 346                 err = usbd_open_pipe(sc->sc_iface, sc->sc_bulkout_no,
 347                                      USBD_EXCLUSIVE_USE, &sc->sc_bulkout_pipe);
 348                 if (err) {
 349                         kprintf("%s: open bulk out error (addr %d): %s\n",
 350                                device_get_nameunit(sc->sc_dev), sc->sc_bulkout_no,
 351                                usbd_errstr(err));
 352                         error = EIO;
 353                         goto fail_1;
 354                 }
 355
 356                 /* Allocate a request and an input buffer and start reading. */
 357                 sc->sc_ixfer = usbd_alloc_xfer(sc->sc_udev);
 358                 if (sc->sc_ixfer == NULL) {
 359                         error = ENOMEM;
 360                         goto fail_2;
 361                 }
 362
 363                 sc->sc_ibuf = usbd_alloc_buffer(sc->sc_ixfer,
 364                                                 sc->sc_ibufsizepad);
 365                 if (sc->sc_ibuf == NULL) {
 366                         error = ENOMEM;
 367                         goto fail_3;
 368                 }
 369
 370                 sc->sc_oxfer = usbd_alloc_xfer(sc->sc_udev);
 371                 if (sc->sc_oxfer == NULL) {
 372                         error = ENOMEM;
 373                         goto fail_3;
 374                 }
 375
 376                 sc->sc_obuf = usbd_alloc_buffer(sc->sc_oxfer,
 377                                                 sc->sc_obufsize +
 378                                                 sc->sc_opkthdrlen);
 379                 if (sc->sc_obuf == NULL) {
 380                         error = ENOMEM;
 381                         goto fail_4;
 382                 }
 383
 384                 /*
 385                  * Handle initial DCD.
 386                  */
 387                 if (ISSET(sc->sc_msr, UMSR_DCD) ||
 388                     (minor(dev) & UCOM_CALLOUT_MASK))
 389                         (*linesw[tp->t_line].l_modem)(tp, 1);
 390
 391                 ucomstartread(sc);
 392         }
 393
 394         sc->sc_opening = 0;
 395         wakeup(&sc->sc_opening);
 396         crit_exit();
 397
 398         error = ttyopen(dev, tp);
 399         if (error)
 400                 goto bad;
 401
 402         error = (*linesw[tp->t_line].l_open)(dev, tp);
 403         if (error)
 404                 goto bad;
 405
 406         disc_optim(tp, &tp->t_termios, sc);
 407
 408         DPRINTF(("%s: ucomopen: success\n", device_get_nameunit(sc->sc_dev)));
 409
 410         sc->sc_poll = 1;
 411         sc->sc_refcnt++;
 412
 413         return (0);
 414
 415 fail_4:
 416         usbd_free_xfer(sc->sc_oxfer);
 417         sc->sc_oxfer = NULL;
 418 fail_3:
 419         usbd_free_xfer(sc->sc_ixfer);
 420         sc->sc_ixfer = NULL;
 421 fail_2:
 422         usbd_close_pipe(sc->sc_bulkout_pipe);
 423         sc->sc_bulkout_pipe = NULL;
 424 fail_1:
 425         usbd_close_pipe(sc->sc_bulkin_pipe);
 426         sc->sc_bulkin_pipe = NULL;
 427 fail_0:
 428         sc->sc_opening = 0;
 429         wakeup(&sc->sc_opening);
 430         crit_exit();
 431         return (error);
 432
 433 bad:
 434         if (!ISSET(tp->t_state, TS_ISOPEN)) {
 435                 /*
 436                  * We failed to open the device, and nobody else had it opened.
 437                  * Clean up the state as appropriate.
 438                  */
 439                 ucom_cleanup(sc);
 440         }
 441
 442         DPRINTF(("%s: ucomopen: failed\n", device_get_nameunit(sc->sc_dev)));
 443
 444         return (error);
 445 }
 446
 447 static int
 448 ucomclose(struct dev_close_args *ap)
 449 {
 450         cdev_t dev = ap->a_head.a_dev;
 451         struct ucom_softc *sc;
 452         struct tty *tp;
 453
 454         sc = devclass_get_softc(ucom_devclass, UCOMUNIT(dev));
 455
 456         tp = sc->sc_tty;
 457
 458         DPRINTF(("%s: ucomclose: unit = %d\n",
 459                 device_get_nameunit(sc->sc_dev), UCOMUNIT(dev)));
 460
 461         if (!ISSET(tp->t_state, TS_ISOPEN))
 462                 goto quit;
 463
 464         crit_enter();
 465         (*linesw[tp->t_line].l_close)(tp, ap->a_fflag);
 466         disc_optim(tp, &tp->t_termios, sc);
 467         ttyclose(tp);
 468         crit_exit();
 469
 470         if (sc->sc_dying)
 471                 goto quit;
 472
 473         if (!ISSET(tp->t_state, TS_ISOPEN)) {
 474                 /*
 475                  * Although we got a last close, the device may still be in
 476                  * use; e.g. if this was the dialout node, and there are still
 477                  * processes waiting for carrier on the non-dialout node.
 478                  */
 479                 ucom_cleanup(sc);
 480         }
 481
 482         if (sc->sc_callback->ucom_close != NULL)
 483                 sc->sc_callback->ucom_close(sc->sc_parent, sc->sc_portno);
 484
 485 quit:
 486         if (tp->t_dev) {
 487                 release_dev(tp->t_dev);
 488                 tp->t_dev = NULL;
 489         }
 490
 491         if (--sc->sc_refcnt < 0)
 492                 usb_detach_wakeup(sc->sc_dev);
 493
 494         return (0);
 495 }
 496
 497 static int
 498 ucomread(struct dev_read_args *ap)
 499 {
 500         cdev_t dev = ap->a_head.a_dev;
 501         struct ucom_softc *sc;
 502         struct tty *tp;
 503         int error;
 504
 505         sc = devclass_get_softc(ucom_devclass, UCOMUNIT(dev));
 506         tp = sc->sc_tty;
 507
 508         DPRINTF(("ucomread: tp = %p, flag = 0x%x\n", tp, ap->a_ioflag));
 509
 510         if (sc->sc_dying)
 511                 return (EIO);
 512
 513         error = (*linesw[tp->t_line].l_read)(tp, ap->a_uio, ap->a_ioflag);
 514
 515         DPRINTF(("ucomread: error = %d\n", error));
 516
 517         return (error);
 518 }
 519
 520 static int
 521 ucomwrite(struct dev_write_args *ap)
 522 {
 523         cdev_t dev = ap->a_head.a_dev;
 524         struct ucom_softc *sc;
 525         struct tty *tp;
 526         int error;
 527
 528         sc = devclass_get_softc(ucom_devclass, UCOMUNIT(dev));
 529         tp = sc->sc_tty;
 530
 531         DPRINTF(("ucomwrite: tp = %p, flag = 0x%x\n", tp, ap->a_ioflag));
 532
 533         if (sc->sc_dying)
 534                 return (EIO);
 535
 536         error = (*linesw[tp->t_line].l_write)(tp, ap->a_uio, ap->a_ioflag);
 537
 538         DPRINTF(("ucomwrite: error = %d\n", error));
 539
 540         return (error);
 541 }
 542
 543 static int
 544 ucomioctl(struct dev_ioctl_args *ap)
 545 {
 546         cdev_t dev = ap->a_head.a_dev;
 547         struct ucom_softc *sc;
 548         struct tty *tp;
 549         int error;
 550         int d;
 551
 552         sc = devclass_get_softc(ucom_devclass, UCOMUNIT(dev));
 553         tp = sc->sc_tty;
 554
 555         if (sc->sc_dying)
 556                 return (EIO);
 557
 558         DPRINTF(("ucomioctl: cmd = 0x%08lx\n", ap->a_cmd));
 559
 560         error = (*linesw[tp->t_line].l_ioctl)(tp, ap->a_cmd, ap->a_data,
 561                                               ap->a_fflag, ap->a_cred);
 562         if (error != ENOIOCTL) {
 563                 DPRINTF(("ucomioctl: l_ioctl: error = %d\n", error));
 564                 return (error);
 565         }
 566
 567         crit_enter();
 568
 569         error = ttioctl(tp, ap->a_cmd, ap->a_data, ap->a_fflag);
 570         disc_optim(tp, &tp->t_termios, sc);
 571         if (error != ENOIOCTL) {
 572                 crit_exit();
 573                 DPRINTF(("ucomioctl: ttioctl: error = %d\n", error));
 574                 return (error);
 575         }
 576
 577         if (sc->sc_callback->ucom_ioctl != NULL) {
 578                 error = sc->sc_callback->ucom_ioctl(sc->sc_parent,
 579                                                     sc->sc_portno,
 580                                                     ap->a_cmd, ap->a_data,
 581                                                     ap->a_fflag, curthread);
 582                 if (error >= 0) {
 583                         crit_exit();
 584                         return (error);
 585                 }
 586         }
 587
 588         error = 0;
 589
 590         DPRINTF(("ucomioctl: our cmd = 0x%08lx\n", ap->a_cmd));
 591
 592         switch (ap->a_cmd) {
 593         case TIOCSBRK:
 594                 DPRINTF(("ucomioctl: TIOCSBRK\n"));
 595                 ucom_break(sc, 1);
 596                 break;
 597         case TIOCCBRK:
 598                 DPRINTF(("ucomioctl: TIOCCBRK\n"));
 599                 ucom_break(sc, 0);
 600                 break;
 601
 602         case TIOCSDTR:
 603                 DPRINTF(("ucomioctl: TIOCSDTR\n"));
 604                 (void)ucomctl(sc, TIOCM_DTR, DMBIS);
 605                 break;
 606         case TIOCCDTR:
 607                 DPRINTF(("ucomioctl: TIOCCDTR\n"));
 608                 (void)ucomctl(sc, TIOCM_DTR, DMBIC);
 609                 break;
 610
 611         case TIOCMSET:
 612                 d = *(int *)ap->a_data;
 613                 DPRINTF(("ucomioctl: TIOCMSET, 0x%x\n", d));
 614                 (void)ucomctl(sc, d, DMSET);
 615                 break;
 616         case TIOCMBIS:
 617                 d = *(int *)ap->a_data;
 618                 DPRINTF(("ucomioctl: TIOCMBIS, 0x%x\n", d));
 619                 (void)ucomctl(sc, d, DMBIS);
 620                 break;
 621         case TIOCMBIC:
 622                 d = *(int *)ap->a_data;
 623                 DPRINTF(("ucomioctl: TIOCMBIC, 0x%x\n", d));
 624                 (void)ucomctl(sc, d, DMBIC);
 625                 break;
 626         case TIOCMGET:
 627                 d = ucomctl(sc, 0, DMGET);
 628                 DPRINTF(("ucomioctl: TIOCMGET, 0x%x\n", d));
 629                 *(int *)ap->a_data = d;
 630                 break;
 631
 632         default:
 633                 DPRINTF(("ucomioctl: error: our cmd = 0x%08lx\n", ap->a_cmd));
 634                 error = ENOTTY;
 635                 break;
 636         }
 637
 638         crit_exit();
 639
 640         return (error);
 641 }
 642
 643 static int
 644 ucomctl(struct ucom_softc *sc, int bits, int how)
 645 {
 646         int     mcr;
 647         int     msr;
 648         int     onoff;
 649
 650         DPRINTF(("ucomctl: bits = 0x%x, how = %d\n", bits, how));
 651
 652         if (how == DMGET) {
 653                 SET(bits, TIOCM_LE);            /* always set TIOCM_LE bit */
 654                 DPRINTF(("ucomctl: DMGET: LE"));
 655
 656                 mcr = sc->sc_mcr;
 657                 if (ISSET(mcr, UMCR_DTR)) {
 658                         SET(bits, TIOCM_DTR);
 659                         DPRINTF((" DTR"));
 660                 }
 661                 if (ISSET(mcr, UMCR_RTS)) {
 662                         SET(bits, TIOCM_RTS);
 663                         DPRINTF((" RTS"));
 664                 }
 665
 666                 msr = sc->sc_msr;
 667                 if (ISSET(msr, UMSR_CTS)) {
 668                         SET(bits, TIOCM_CTS);
 669                         DPRINTF((" CTS"));
 670                 }
 671                 if (ISSET(msr, UMSR_DCD)) {
 672                         SET(bits, TIOCM_CD);
 673                         DPRINTF((" CD"));
 674                 }
 675                 if (ISSET(msr, UMSR_DSR)) {
 676                         SET(bits, TIOCM_DSR);
 677                         DPRINTF((" DSR"));
 678                 }
 679                 if (ISSET(msr, UMSR_RI)) {
 680                         SET(bits, TIOCM_RI);
 681                         DPRINTF((" RI"));
 682                 }
 683
 684                 DPRINTF(("\n"));
 685
 686                 return (bits);
 687         }
 688
 689         mcr = 0;
 690         if (ISSET(bits, TIOCM_DTR))
 691                 SET(mcr, UMCR_DTR);
 692         if (ISSET(bits, TIOCM_RTS))
 693                 SET(mcr, UMCR_RTS);
 694
 695         switch (how) {
 696         case DMSET:
 697                 sc->sc_mcr = mcr;
 698                 break;
 699         case DMBIS:
 700                 sc->sc_mcr |= mcr;
 701                 break;
 702         case DMBIC:
 703                 sc->sc_mcr &= ~mcr;
 704                 break;
 705         }
 706
 707         onoff = ISSET(sc->sc_mcr, UMCR_DTR) ? 1 : 0;
 708         ucom_dtr(sc, onoff);
 709
 710         onoff = ISSET(sc->sc_mcr, UMCR_RTS) ? 1 : 0;
 711         ucom_rts(sc, onoff);
 712
 713         return (0);
 714 }
 715
 716 static void
 717 ucom_break(struct ucom_softc *sc, int onoff)
 718 {
 719         DPRINTF(("ucom_break: onoff = %d\n", onoff));
 720
 721         if (sc->sc_callback->ucom_set == NULL)
 722                 return;
 723         sc->sc_callback->ucom_set(sc->sc_parent, sc->sc_portno,
 724                                   UCOM_SET_BREAK, onoff);
 725 }
 726
 727 static void
 728 ucom_dtr(struct ucom_softc *sc, int onoff)
 729 {
 730         DPRINTF(("ucom_dtr: onoff = %d\n", onoff));
 731
 732         if (sc->sc_callback->ucom_set == NULL)
 733                 return;
 734         sc->sc_callback->ucom_set(sc->sc_parent, sc->sc_portno,
 735                                   UCOM_SET_DTR, onoff);
 736 }
 737
 738 static void
 739 ucom_rts(struct ucom_softc *sc, int onoff)
 740 {
 741         DPRINTF(("ucom_rts: onoff = %d\n", onoff));
 742
 743         if (sc->sc_callback->ucom_set == NULL)
 744                 return;
 745         sc->sc_callback->ucom_set(sc->sc_parent, sc->sc_portno,
 746                                   UCOM_SET_RTS, onoff);
 747 }
 748
 749 void
 750 ucom_status_change(struct ucom_softc *sc)
 751 {
 752         struct tty *tp = sc->sc_tty;
 753         u_char old_msr;
 754         int onoff;
 755
 756         if (sc->sc_callback->ucom_get_status == NULL) {
 757                 sc->sc_lsr = 0;
 758                 sc->sc_msr = 0;
 759                 return;
 760         }
 761
 762         old_msr = sc->sc_msr;
 763         sc->sc_callback->ucom_get_status(sc->sc_parent, sc->sc_portno,
 764                                          &sc->sc_lsr, &sc->sc_msr);
 765         if (ISSET((sc->sc_msr ^ old_msr), UMSR_DCD)) {
 766                 if (sc->sc_poll == 0)
 767                         return;
 768                 onoff = ISSET(sc->sc_msr, UMSR_DCD) ? 1 : 0;
 769                 DPRINTF(("ucom_status_change: DCD changed to %d\n", onoff));
 770                 (*linesw[tp->t_line].l_modem)(tp, onoff);
 771         }
 772 }
 773
 774 static int
 775 ucomparam(struct tty *tp, struct termios *t)
 776 {
 777         struct ucom_softc *sc;
 778         int error;
 779         usbd_status uerr;
 780
 781         sc = devclass_get_softc(ucom_devclass, UCOMUNIT(tp->t_dev));
 782
 783         if (sc->sc_dying)
 784                 return (EIO);
 785
 786         DPRINTF(("ucomparam: sc = %p\n", sc));
 787
 788         /* Check requested parameters. */
 789         if (t->c_ospeed < 0) {
 790                 DPRINTF(("ucomparam: negative ospeed\n"));
 791                 return (EINVAL);
 792         }
 793         if (t->c_ispeed && t->c_ispeed != t->c_ospeed) {
 794                 DPRINTF(("ucomparam: mismatch ispeed and ospeed\n"));
 795                 return (EINVAL);
 796         }
 797
 798         /*
 799          * If there were no changes, don't do anything.  This avoids dropping
 800          * input and improves performance when all we did was frob things like
 801          * VMIN and VTIME.
 802          */
 803         if (tp->t_ospeed == t->c_ospeed &&
 804             tp->t_cflag == t->c_cflag)
 805                 return (0);
 806
 807         /* And copy to tty. */
 808         tp->t_ispeed = 0;
 809         tp->t_ospeed = t->c_ospeed;
 810         tp->t_cflag = t->c_cflag;
 811
 812         if (sc->sc_callback->ucom_param == NULL)
 813                 return (0);
 814
 815         ucomstopread(sc);
 816
 817         error = sc->sc_callback->ucom_param(sc->sc_parent, sc->sc_portno, t);
 818         if (error) {
 819                 DPRINTF(("ucomparam: callback: error = %d\n", error));
 820                 return (error);
 821         }
 822
 823         ttsetwater(tp);
 824
 825         if (t->c_cflag & CRTS_IFLOW) {
 826                 sc->sc_state |= UCS_RTS_IFLOW;
 827         } else if (sc->sc_state & UCS_RTS_IFLOW) {
 828                 sc->sc_state &= ~UCS_RTS_IFLOW;
 829                 (void)ucomctl(sc, UMCR_RTS, DMBIS);
 830         }
 831
 832         disc_optim(tp, t, sc);
 833
 834         uerr = ucomstartread(sc);
 835         if (uerr != USBD_NORMAL_COMPLETION)
 836                 return (EIO);
 837
 838         return (0);
 839 }
 840
 841 static void
 842 ucomstart(struct tty *tp)
 843 {
 844         struct ucom_softc *sc;
 845         struct cblock *cbp;
 846         usbd_status err;
 847         u_char *data;
 848         int cnt;
 849
 850         sc = devclass_get_softc(ucom_devclass, UCOMUNIT(tp->t_dev));
 851         DPRINTF(("ucomstart: sc = %p\n", sc));
 852
 853         if (sc->sc_dying)
 854                 return;
 855
 856         crit_enter();
 857
 858         if (tp->t_state & TS_TBLOCK) {
 859                 if (ISSET(sc->sc_mcr, UMCR_RTS) &&
 860                     ISSET(sc->sc_state, UCS_RTS_IFLOW)) {
 861                         DPRINTF(("ucomstart: clear RTS\n"));
 862                         (void)ucomctl(sc, UMCR_RTS, DMBIC);
 863                 }
 864         } else {
 865                 if (!ISSET(sc->sc_mcr, UMCR_RTS) &&
 866                     tp->t_rawq.c_cc <= tp->t_ilowat &&
 867                     ISSET(sc->sc_state, UCS_RTS_IFLOW)) {
 868                         DPRINTF(("ucomstart: set RTS\n"));
 869                         (void)ucomctl(sc, UMCR_RTS, DMBIS);
 870                 }
 871         }
 872
 873         if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP)) {
 874                 ttwwakeup(tp);
 875                 DPRINTF(("ucomstart: stopped\n"));
 876                 goto out;
 877         }
 878
 879         if (tp->t_outq.c_cc <= tp->t_olowat) {
 880                 if (ISSET(tp->t_state, TS_SO_OLOWAT)) {
 881                         CLR(tp->t_state, TS_SO_OLOWAT);
 882                         wakeup(TSA_OLOWAT(tp));
 883                 }
 884                 selwakeuppri(&tp->t_wsel, TTIPRI);
 885                 if (tp->t_outq.c_cc == 0) {
 886                         if (ISSET(tp->t_state, TS_BUSY | TS_SO_OCOMPLETE) ==
 887                             TS_SO_OCOMPLETE && tp->t_outq.c_cc == 0) {
 888                                 CLR(tp->t_state, TS_SO_OCOMPLETE);
 889                                 wakeup(TSA_OCOMPLETE(tp));
 890                         }
 891                         goto out;
 892                 }
 893         }
 894
 895         /* Grab the first contiguous region of buffer space. */
 896         data = tp->t_outq.c_cf;
 897         cbp = (struct cblock *) ((intptr_t) tp->t_outq.c_cf & ~CROUND);
 898         cnt = min((char *) (cbp+1) - tp->t_outq.c_cf, tp->t_outq.c_cc);
 899
 900         if (cnt == 0) {
 901                 DPRINTF(("ucomstart: cnt == 0\n"));
 902                 goto out;
 903         }
 904
 905         SET(tp->t_state, TS_BUSY);
 906
 907         if (cnt > sc->sc_obufsize) {
 908                 DPRINTF(("ucomstart: big buffer %d chars\n", cnt));
 909                 cnt = sc->sc_obufsize;
 910         }
 911         if (sc->sc_callback->ucom_write != NULL)
 912                 sc->sc_callback->ucom_write(sc->sc_parent, sc->sc_portno,
 913                                             sc->sc_obuf, data, &cnt);
 914         else
 915                 memcpy(sc->sc_obuf, data, cnt);
 916
 917         DPRINTF(("ucomstart: %d chars\n", cnt));
 918         usbd_setup_xfer(sc->sc_oxfer, sc->sc_bulkout_pipe,
 919                         (usbd_private_handle)sc, sc->sc_obuf, cnt,
 920                         USBD_NO_COPY, USBD_NO_TIMEOUT, ucomwritecb);
 921         /* What can we do on error? */
 922         err = usbd_transfer(sc->sc_oxfer);
 923         if (err != USBD_IN_PROGRESS)
 924                 kprintf("ucomstart: err=%s\n", usbd_errstr(err));
 925
 926         ttwwakeup(tp);
 927
 928     out:
 929         crit_exit();
 930 }
 931
 932 static void
 933 ucomstop(struct tty *tp, int flag)
 934 {
 935         struct ucom_softc *sc;
 936
 937         sc = devclass_get_softc(ucom_devclass, UCOMUNIT(tp->t_dev));
 938
 939         DPRINTF(("ucomstop: %d\n", flag));
 940
 941         if (flag & FREAD) {
 942                 /*
 943                  * This is just supposed to flush pending receive data,
 944                  * not stop the reception of data entirely!
 945                  */
 946                 DPRINTF(("ucomstop: read\n"));
 947                 ucomstopread(sc);
 948                 ucomstartread(sc);
 949         }
 950
 951         if (flag & FWRITE) {
 952                 DPRINTF(("ucomstop: write\n"));
 953                 crit_enter();
 954                 if (ISSET(tp->t_state, TS_BUSY)) {
 955                         /* XXX do what? */
 956                         if (!ISSET(tp->t_state, TS_TTSTOP))
 957                                 SET(tp->t_state, TS_FLUSH);
 958                 }
 959                 crit_exit();
 960         }
 961
 962         DPRINTF(("ucomstop: done\n"));
 963 }
 964
 965 static void
 966 ucomwritecb(usbd_xfer_handle xfer, usbd_private_handle p, usbd_status status)
 967 {
 968         struct ucom_softc *sc = (struct ucom_softc *)p;
 969         struct tty *tp = sc->sc_tty;
 970         u_int32_t cc;
 971
 972         DPRINTF(("ucomwritecb: status = %d\n", status));
 973
 974         if (status == USBD_CANCELLED || sc->sc_dying)
 975                 goto error;
 976
 977         if (status != USBD_NORMAL_COMPLETION) {
 978                 kprintf("%s: ucomwritecb: %s\n",
 979                        device_get_nameunit(sc->sc_dev), usbd_errstr(status));
 980                 if (status == USBD_STALLED)
 981                         usbd_clear_endpoint_stall_async(sc->sc_bulkin_pipe);
 982                 /*
 983                  * XXX.  We may need a flag to sequence ucomstopread() and
 984                  * ucomstartread() to handle the case where ucomstartread()
 985                  * is called after ucomstopread() but before the request has
 986                  * been properly canceled?
 987                  */
 988                 goto error;
 989         }
 990
 991         usbd_get_xfer_status(xfer, NULL, NULL, &cc, NULL);
 992         DPRINTF(("ucomwritecb: cc = %d\n", cc));
 993         if (cc <= sc->sc_opkthdrlen) {
 994                 kprintf("%s: sent size too small, cc = %d\n",
 995                         device_get_nameunit(sc->sc_dev), cc);
 996                 goto error;
 997         }
 998
 999         /* convert from USB bytes to tty bytes */
1000         cc -= sc->sc_opkthdrlen;
1001
1002         crit_enter();
1003         CLR(tp->t_state, TS_BUSY);
1004         if (ISSET(tp->t_state, TS_FLUSH))
1005                 CLR(tp->t_state, TS_FLUSH);
1006         else
1007                 ndflush(&tp->t_outq, cc);
1008         (*linesw[tp->t_line].l_start)(tp);
1009         crit_exit();
1010
1011         return;
1012
1013   error:
1014         crit_enter();
1015         CLR(tp->t_state, TS_BUSY);
1016         crit_exit();
1017         return;
1018 }
1019
1020 static usbd_status
1021 ucomstartread(struct ucom_softc *sc)
1022 {
1023         usbd_status err;
1024
1025         DPRINTF(("ucomstartread: start\n"));
1026
1027         sc->sc_state &= ~UCS_RXSTOP;
1028
1029         if (sc->sc_bulkin_pipe == NULL)
1030                 return (USBD_NORMAL_COMPLETION);
1031
1032         usbd_setup_xfer(sc->sc_ixfer, sc->sc_bulkin_pipe,
1033                         (usbd_private_handle)sc,
1034                         sc->sc_ibuf, sc->sc_ibufsize,
1035                         USBD_SHORT_XFER_OK | USBD_NO_COPY,
1036                         USBD_NO_TIMEOUT, ucomreadcb);
1037
1038         err = usbd_transfer(sc->sc_ixfer);
1039         if (err != USBD_IN_PROGRESS) {
1040                 DPRINTF(("ucomstartread: err = %s\n", usbd_errstr(err)));
1041                 return (err);
1042         }
1043
1044         return (USBD_NORMAL_COMPLETION);
1045 }
1046
1047 static void
1048 ucomreadcb(usbd_xfer_handle xfer, usbd_private_handle p, usbd_status status)
1049 {
1050         struct ucom_softc *sc = (struct ucom_softc *)p;
1051         struct tty *tp = sc->sc_tty;
1052         int (*rint) (int c, struct tty *tp) = linesw[tp->t_line].l_rint;
1053         usbd_status err;
1054         u_int32_t cc;
1055         u_char *cp;
1056         int lostcc;
1057
1058         DPRINTF(("ucomreadcb: status = %d\n", status));
1059
1060         if (status != USBD_NORMAL_COMPLETION) {
1061                 if (!(sc->sc_state & UCS_RXSTOP))
1062                         kprintf("%s: ucomreadcb: %s\n",
1063                                device_get_nameunit(sc->sc_dev), usbd_errstr(status));
1064                 if (status == USBD_STALLED)
1065                         usbd_clear_endpoint_stall_async(sc->sc_bulkin_pipe);
1066                 /* XXX we should restart after some delay. */
1067                 return;
1068         }
1069
1070         usbd_get_xfer_status(xfer, NULL, (void **)&cp, &cc, NULL);
1071         DPRINTF(("ucomreadcb: got %d chars, tp = %p\n", cc, tp));
1072         if (cc == 0)
1073                 goto resubmit;
1074
1075         if (sc->sc_callback->ucom_read != NULL) {
1076                 sc->sc_callback->ucom_read(sc->sc_parent, sc->sc_portno,
1077                                            &cp, &cc);
1078         }
1079
1080         if (cc > sc->sc_ibufsize) {
1081                 kprintf("%s: invalid receive data size, %d chars\n",
1082                         device_get_nameunit(sc->sc_dev), cc);
1083                 goto resubmit;
1084         }
1085         if (cc < 1)
1086                 goto resubmit;
1087
1088         crit_enter();
1089         if (tp->t_state & TS_CAN_BYPASS_L_RINT) {
1090                 if (tp->t_rawq.c_cc + cc > tp->t_ihiwat
1091                     && (sc->sc_state & UCS_RTS_IFLOW
1092                         || tp->t_iflag & IXOFF)
1093                     && !(tp->t_state & TS_TBLOCK))
1094                         ttyblock(tp);
1095                 lostcc = b_to_q((char *)cp, cc, &tp->t_rawq);
1096                 tp->t_rawcc += cc;
1097                 if (sc->hotchar) {
1098                         while (cc) {
1099                                 if (*cp == sc->hotchar)
1100                                         break;
1101                                 --cc;
1102                                 ++cp;
1103                         }
1104                         if (cc)
1105                                 setsofttty();
1106                 }
1107                 ttwakeup(tp);
1108                 if (tp->t_state & TS_TTSTOP
1109                     && (tp->t_iflag & IXANY
1110                         || tp->t_cc[VSTART] == tp->t_cc[VSTOP])) {
1111                         tp->t_state &= ~TS_TTSTOP;
1112                         tp->t_lflag &= ~FLUSHO;
1113                         ucomstart(tp);
1114                 }
1115                 if (lostcc > 0)
1116                         kprintf("%s: lost %d chars\n", device_get_nameunit(sc->sc_dev),
1117                                lostcc);
1118         } else {
1119                 /* Give characters to tty layer. */
1120                 while (cc > 0) {
1121                         DPRINTFN(7, ("ucomreadcb: char = 0x%02x\n", *cp));
1122                         if ((*rint)(*cp, tp) == -1) {
1123                                 /* XXX what should we do? */
1124                                 kprintf("%s: lost %d chars\n",
1125                                        device_get_nameunit(sc->sc_dev), cc);
1126                                 break;
1127                         }
1128                         cc--;
1129                         cp++;
1130                 }
1131         }
1132         crit_exit();
1133
1134 resubmit:
1135         err = ucomstartread(sc);
1136         if (err) {
1137                 kprintf("%s: read start failed\n", device_get_nameunit(sc->sc_dev));
1138                 /* XXX what should we dow now? */
1139         }
1140
1141         if ((sc->sc_state & UCS_RTS_IFLOW) && !ISSET(sc->sc_mcr, UMCR_RTS)
1142             && !(tp->t_state & TS_TBLOCK))
1143                 ucomctl(sc, UMCR_RTS, DMBIS);
1144 }
1145
1146 static void
1147 ucom_cleanup(struct ucom_softc *sc)
1148 {
1149         DPRINTF(("ucom_cleanup: closing pipes\n"));
1150
1151         ucom_shutdown(sc);
1152         if (sc->sc_bulkin_pipe != NULL) {
1153                 usbd_abort_pipe(sc->sc_bulkin_pipe);
1154                 usbd_close_pipe(sc->sc_bulkin_pipe);
1155                 sc->sc_bulkin_pipe = NULL;
1156         }
1157         if (sc->sc_bulkout_pipe != NULL) {
1158                 usbd_abort_pipe(sc->sc_bulkout_pipe);
1159                 usbd_close_pipe(sc->sc_bulkout_pipe);
1160                 sc->sc_bulkout_pipe = NULL;
1161         }
1162         if (sc->sc_ixfer != NULL) {
1163                 usbd_free_xfer(sc->sc_ixfer);
1164                 sc->sc_ixfer = NULL;
1165         }
1166         if (sc->sc_oxfer != NULL) {
1167                 usbd_free_xfer(sc->sc_oxfer);
1168                 sc->sc_oxfer = NULL;
1169         }
1170 }
1171
1172 static void
1173 ucomstopread(struct ucom_softc *sc)
1174 {
1175         usbd_status err;
1176
1177         DPRINTF(("ucomstopread: enter\n"));
1178
1179         if (!(sc->sc_state & UCS_RXSTOP)) {
1180                 sc->sc_state |= UCS_RXSTOP;
1181                 if (sc->sc_bulkin_pipe == NULL) {
1182                         DPRINTF(("ucomstopread: bulkin pipe NULL\n"));
1183                         return;
1184                 }
1185                 err = usbd_abort_pipe(sc->sc_bulkin_pipe);
1186                 if (err) {
1187                         DPRINTF(("ucomstopread: err = %s\n",
1188                                  usbd_errstr(err)));
1189                 }
1190         }
1191
1192         DPRINTF(("ucomstopread: leave\n"));
1193 }
1194
1195 static void
1196 disc_optim(struct tty *tp, struct termios *t, struct ucom_softc *sc)
1197 {
1198         if (!(t->c_iflag & (ICRNL | IGNCR | IMAXBEL | INLCR | ISTRIP | IXON))
1199             && (!(t->c_iflag & BRKINT) || (t->c_iflag & IGNBRK))
1200             && (!(t->c_iflag & PARMRK)
1201                 || (t->c_iflag & (IGNPAR | IGNBRK)) == (IGNPAR | IGNBRK))
1202             && !(t->c_lflag & (ECHO | ICANON | IEXTEN | ISIG | PENDIN))
1203             && linesw[tp->t_line].l_rint == ttyinput) {
1204                 DPRINTF(("disc_optim: bypass l_rint\n"));
1205                 tp->t_state |= TS_CAN_BYPASS_L_RINT;
1206         } else {
1207                 DPRINTF(("disc_optim: can't bypass l_rint\n"));
1208                 tp->t_state &= ~TS_CAN_BYPASS_L_RINT;
1209         }
1210         sc->hotchar = linesw[tp->t_line].l_hotchar;
1211 }