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IABSD.fr/src/sys/dev/usb/ucom.c

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  • Author : jsg
    Date : 2024-05-23 03:21:08
    Hash : 81508fe3
    Message : remove unneeded includes; ok mpi@

  • sys/dev/usb/ucom.c
  • /*	$OpenBSD: ucom.c,v 1.79 2024/05/23 03:21:09 jsg Exp $ */
    /*	$NetBSD: ucom.c,v 1.49 2003/01/01 00:10:25 thorpej Exp $	*/
    
    /*
     * Copyright (c) 1998, 2000 The NetBSD Foundation, Inc.
     * All rights reserved.
     *
     * This code is derived from software contributed to The NetBSD Foundation
     * by Lennart Augustsson (lennart@augustsson.net) at
     * Carlstedt Research & Technology.
     *
     * Redistribution and use in source and binary forms, with or without
     * modification, are permitted provided that the following conditions
     * are met:
     * 1. Redistributions of source code must retain the above copyright
     *    notice, this list of conditions and the following disclaimer.
     * 2. Redistributions in binary form must reproduce the above copyright
     *    notice, this list of conditions and the following disclaimer in the
     *    documentation and/or other materials provided with the distribution.
     *
     * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     * POSSIBILITY OF SUCH DAMAGE.
     */
    /*
     * This code is very heavily based on the 16550 driver, com.c.
     */
    
    #include <sys/param.h>
    #include <sys/systm.h>
    #include <sys/rwlock.h>
    #include <sys/ioctl.h>
    #include <sys/conf.h>
    #include <sys/tty.h>
    #include <sys/fcntl.h>
    #include <sys/vnode.h>
    #include <sys/device.h>
    #include <sys/malloc.h>
    
    #include <dev/usb/usb.h>
    
    #include <dev/usb/usbdi.h>
    #include <dev/usb/usbdi_util.h>
    #include <dev/usb/uhidev.h>
    
    #include <dev/usb/ucomvar.h>
    
    #include "ucom.h"
    
    #if NUCOM > 0
    
    #ifdef UCOM_DEBUG
    #define DPRINTFN(n, x)	do { if (ucomdebug > (n)) printf x; } while (0)
    int ucomdebug = 0;
    #else
    #define DPRINTFN(n, x)
    #endif
    #define DPRINTF(x) DPRINTFN(0, x)
    
    #define	UCOMUNIT_MASK		0x7f
    #define	UCOMCUA_MASK		0x80
    
    #define LINESW(tp, func)	(linesw[(tp)->t_line].func)
    
    #define	UCOMUNIT(x)		(minor(x) & UCOMUNIT_MASK)
    #define	UCOMCUA(x)		(minor(x) & UCOMCUA_MASK)
    
    #define ROUTEROOTPORT(_x)	((_x) & 0xff)
    #define ROUTESTRING(_x)		(((_x) >> 8) & 0xfffff)
    
    struct ucom_softc {
    	struct device		sc_dev;		/* base device */
    
    	struct usbd_device	*sc_uparent;	/* USB device */
    	struct uhidev_softc	*sc_uhidev;	/* hid device (if deeper) */
    
    	struct usbd_interface	*sc_iface;	/* data interface */
    
    	int			sc_bulkin_no;	/* bulk in endpoint address */
    	struct usbd_pipe	*sc_bulkin_pipe;/* bulk in pipe */
    	struct usbd_xfer	*sc_ixfer;	/* read request */
    	u_char			*sc_ibuf;	/* read buffer */
    	u_int			sc_ibufsize;	/* read buffer size */
    	u_int			sc_ibufsizepad;	/* read buffer size padded */
    
    	int			sc_bulkout_no;	/* bulk out endpoint address */
    	struct usbd_pipe	*sc_bulkout_pipe;/* bulk out pipe */
    	struct usbd_xfer	*sc_oxfer;	/* write request */
    	u_char			*sc_obuf;	/* write buffer */
    	u_int			sc_obufsize;	/* write buffer size */
    	u_int			sc_opkthdrlen;	/* header length of
    						 * output packet */
    
    	struct usbd_pipe	*sc_ipipe;	/* hid interrupt input pipe */
    	struct usbd_pipe	*sc_opipe;	/* hid interrupt pipe */
    
    	const struct ucom_methods *sc_methods;
    	void                    *sc_parent;
    	int			sc_portno;
    
    	struct tty		*sc_tty;	/* our tty */
    	u_char			sc_lsr;
    	u_char			sc_msr;
    	u_char			sc_mcr;
    	u_char			sc_tx_stopped;
    	int			sc_swflags;
    
    	u_char			sc_cua;
    	int			sc_error;
    
    	struct rwlock		sc_lock;	/* lock during open */
    	int			sc_open;
    	int			sc_refcnt;
    };
    
    void	ucom_cleanup(struct ucom_softc *);
    void	ucom_hwiflow(struct ucom_softc *);
    int	ucomparam(struct tty *, struct termios *);
    void	ucomstart(struct tty *);
    void	ucom_shutdown(struct ucom_softc *);
    int	ucom_do_open(dev_t, int, int, struct proc *);
    int	ucom_do_ioctl(struct ucom_softc *, u_long, caddr_t, int, struct proc *);
    int	ucom_do_close(struct ucom_softc *, int, int , struct proc *);
    void	ucom_dtr(struct ucom_softc *, int);
    void	ucom_rts(struct ucom_softc *, int);
    void	ucom_break(struct ucom_softc *, int);
    usbd_status ucomstartread(struct ucom_softc *);
    void	ucomreadcb(struct usbd_xfer *, void *, usbd_status);
    void	ucomwritecb(struct usbd_xfer *, void *, usbd_status);
    void	tiocm_to_ucom(struct ucom_softc *, u_long, int);
    int	ucom_to_tiocm(struct ucom_softc *);
    void	ucom_lock(struct ucom_softc *);
    void	ucom_unlock(struct ucom_softc *);
    
    int ucom_match(struct device *, void *, void *);
    void ucom_attach(struct device *, struct device *, void *);
    int ucom_detach(struct device *, int);
    
    struct cfdriver ucom_cd = {
    	NULL, "ucom", DV_TTY
    };
    
    const struct cfattach ucom_ca = {
    	sizeof(struct ucom_softc),
    	ucom_match,
    	ucom_attach,
    	ucom_detach,
    };
    
    static int ucom_change;
    struct rwlock sysctl_ucomlock = RWLOCK_INITIALIZER("sysctlulk");
    
    void
    ucom_lock(struct ucom_softc *sc)
    {
    	rw_enter_write(&sc->sc_lock);
    }
    
    void
    ucom_unlock(struct ucom_softc *sc)
    {
    	rw_exit_write(&sc->sc_lock);
    }
    
    int
    ucom_match(struct device *parent, void *match, void *aux)
    {
    	return (1);
    }
    
    void
    ucom_attach(struct device *parent, struct device *self, void *aux)
    {
    	char path[32];	/* "usb000.000.00000.000" */
    	struct ucom_softc *sc = (struct ucom_softc *)self;
    	struct ucom_attach_args *uca = aux;
    	struct tty *tp;
    	uint32_t route;
    	uint8_t bus, ifaceno;
    
    	if (uca->info != NULL)
    		printf(", %s", uca->info);
    
    	sc->sc_uparent = uca->device;
    	sc->sc_iface = uca->iface;
    	sc->sc_bulkout_no = uca->bulkout;
    	sc->sc_bulkin_no = uca->bulkin;
    	sc->sc_uhidev = uca->uhidev;
    	sc->sc_ibufsize = uca->ibufsize;
    	sc->sc_ibufsizepad = uca->ibufsizepad;
    	sc->sc_obufsize = uca->obufsize;
    	sc->sc_opkthdrlen = uca->opkthdrlen;
    	sc->sc_methods = uca->methods;
    	sc->sc_parent = uca->arg;
    	sc->sc_portno = uca->portno;
    
    	if (usbd_get_location(sc->sc_uparent, sc->sc_iface, &bus, &route,
    	    &ifaceno) == 0) {
    		if (snprintf(path, sizeof(path), "usb%u.%u.%05x.%u", bus,
    		    ROUTEROOTPORT(route), ROUTESTRING(route), ifaceno) <
    		    sizeof(path))
    			printf(": %s", path);
    	}
    	printf("\n");
    
    	tp = ttymalloc(1000000);
    	tp->t_oproc = ucomstart;
    	tp->t_param = ucomparam;
    	sc->sc_tty = tp;
    	sc->sc_cua = 0;
    
    	ucom_change = 1;
    	rw_init(&sc->sc_lock, "ucomlk");
    }
    
    int
    ucom_detach(struct device *self, int flags)
    {
    	struct ucom_softc *sc = (struct ucom_softc *)self;
    	struct tty *tp = sc->sc_tty;
    	int maj, mn;
    	int s;
    
    	DPRINTF(("ucom_detach: sc=%p flags=%d tp=%p, pipe=%d,%d\n",
    		 sc, flags, tp, sc->sc_bulkin_no, sc->sc_bulkout_no));
    
    	if (sc->sc_bulkin_pipe != NULL) {
    		usbd_close_pipe(sc->sc_bulkin_pipe);
    		sc->sc_bulkin_pipe = NULL;
    	}
    	if (sc->sc_bulkout_pipe != NULL) {
    		usbd_close_pipe(sc->sc_bulkout_pipe);
    		sc->sc_bulkout_pipe = NULL;
    	}
    	if (sc->sc_ixfer != NULL) {
    		if (sc->sc_bulkin_no != -1) {
    			usbd_free_buffer(sc->sc_ixfer);
    			sc->sc_ibuf = NULL;
    			usbd_free_xfer(sc->sc_ixfer);
    		}
    		sc->sc_ixfer = NULL;
    	}
    	if (sc->sc_oxfer != NULL) {
    		usbd_free_buffer(sc->sc_oxfer);
    		sc->sc_obuf = NULL;
    		if (sc->sc_bulkin_no != -1)
    			usbd_free_xfer(sc->sc_oxfer);
    		sc->sc_oxfer = NULL;
    	}
    
    	s = splusb();
    	if (--sc->sc_refcnt >= 0) {
    		/* Wake up anyone waiting */
    		if (tp != NULL) {
    			CLR(tp->t_state, TS_CARR_ON);
    			CLR(tp->t_cflag, CLOCAL | MDMBUF);
    			ttyflush(tp, FREAD|FWRITE);
    		}
    		usb_detach_wait(&sc->sc_dev);
    	}
    	splx(s);
    
    	/* locate the major number */
    	for (maj = 0; maj < nchrdev; maj++)
    		if (cdevsw[maj].d_open == ucomopen)
    			break;
    
    	/* Nuke the vnodes for any open instances. */
    	mn = self->dv_unit;
    	DPRINTF(("ucom_detach: maj=%d mn=%d\n", maj, mn));
    	vdevgone(maj, mn, mn, VCHR);
    	vdevgone(maj, mn | UCOMCUA_MASK, mn | UCOMCUA_MASK, VCHR);
    
    	/* Detach and free the tty. */
    	if (tp != NULL) {
    		(*LINESW(tp, l_close))(tp, FNONBLOCK, curproc);
    		s = spltty();
    		CLR(tp->t_state, TS_BUSY | TS_FLUSH);
    		ttyclose(tp);
    		splx(s);
    		ttyfree(tp);
    		sc->sc_tty = NULL;
    	}
    
    	ucom_change = 1;
    	return (0);
    }
    
    void
    ucom_shutdown(struct ucom_softc *sc)
    {
    	struct tty *tp = sc->sc_tty;
    
    	DPRINTF(("ucom_shutdown\n"));
    	/*
    	 * Hang up if necessary.  Wait a bit, so the other side has time to
    	 * notice even if we immediately open the port again.
    	 */
    	if (ISSET(tp->t_cflag, HUPCL)) {
    		ucom_dtr(sc, 0);
    		ucom_rts(sc, 0);
    		tsleep_nsec(sc, TTIPRI, ttclos, SEC_TO_NSEC(1));
    	}
    }
    
    int
    ucomopen(dev_t dev, int flag, int mode, struct proc *p)
    {
    	int unit = UCOMUNIT(dev);
    	struct ucom_softc *sc;
    	int error;
    
    	if (unit >= ucom_cd.cd_ndevs)
    		return (ENXIO);
    	sc = ucom_cd.cd_devs[unit];
    	if (sc == NULL)
    		return (ENXIO);
    
    	sc->sc_error = 0;
    
    	if (usbd_is_dying(sc->sc_uparent))
    		return (EIO);
    
    	if (ISSET(sc->sc_dev.dv_flags, DVF_ACTIVE) == 0)
    		return (ENXIO);
    
    	sc->sc_refcnt++;
    	error = ucom_do_open(dev, flag, mode, p);
    	if (--sc->sc_refcnt < 0)
    		usb_detach_wakeup(&sc->sc_dev);
    
    	return (error);
    }
    
    int
    ucom_do_open(dev_t dev, int flag, int mode, struct proc *p)
    {
    	struct ucom_softc *sc = ucom_cd.cd_devs[UCOMUNIT(dev)];
    	usbd_status err;
    	struct tty *tp;
    	struct termios t;
    	int error, s;
    
    	/* open the pipes if this is the first open */
    	ucom_lock(sc);
    	s = splusb();
    	if (sc->sc_open == 0) {
    		DPRINTF(("ucomopen: open pipes in=%d out=%d\n",
    		    sc->sc_bulkin_no, sc->sc_bulkout_no));
    		DPRINTF(("ucomopen: hid %p pipes in=%p out=%p\n",
    		    sc->sc_uhidev, sc->sc_ipipe, sc->sc_opipe));
    
    		if (sc->sc_bulkin_no != -1) {
    
    			/* Open the bulk pipes */
    			err = usbd_open_pipe(sc->sc_iface, sc->sc_bulkin_no, 0,
    			    &sc->sc_bulkin_pipe);
    			if (err) {
    				DPRINTF(("%s: open bulk out error (addr %d), err=%s\n",
    				    sc->sc_dev.dv_xname, sc->sc_bulkin_no,
    				    usbd_errstr(err)));
    				error = EIO;
    				goto fail_0;
    			}
    			err = usbd_open_pipe(sc->sc_iface, sc->sc_bulkout_no,
    			    USBD_EXCLUSIVE_USE, &sc->sc_bulkout_pipe);
    			if (err) {
    				DPRINTF(("%s: open bulk in error (addr %d), err=%s\n",
    				    sc->sc_dev.dv_xname, sc->sc_bulkout_no,
    				    usbd_errstr(err)));
    				error = EIO;
    				goto fail_1;
    			}
    
    			/* Allocate a request and an input buffer and start reading. */
    			sc->sc_ixfer = usbd_alloc_xfer(sc->sc_uparent);
    			if (sc->sc_ixfer == NULL) {
    				error = ENOMEM;
    				goto fail_2;
    			}
    
    			sc->sc_ibuf = usbd_alloc_buffer(sc->sc_ixfer,
    			    sc->sc_ibufsizepad);
    			if (sc->sc_ibuf == NULL) {
    				error = ENOMEM;
    				goto fail_2;
    			}
    
    			sc->sc_oxfer = usbd_alloc_xfer(sc->sc_uparent);
    			if (sc->sc_oxfer == NULL) {
    				error = ENOMEM;
    				goto fail_3;
    			}
    		} else {
    			/*
    			 * input/output pipes and xfers already allocated
    			 * as is the input buffer.
    			 */
    			sc->sc_ipipe = sc->sc_uhidev->sc_ipipe;
    			sc->sc_ixfer = sc->sc_uhidev->sc_ixfer;
    			sc->sc_opipe = sc->sc_uhidev->sc_opipe;
    			sc->sc_oxfer = sc->sc_uhidev->sc_oxfer;
    		}
    
    		sc->sc_obuf = usbd_alloc_buffer(sc->sc_oxfer,
    		    sc->sc_obufsize + sc->sc_opkthdrlen);
    		if (sc->sc_obuf == NULL) {
    			error = ENOMEM;
    			goto fail_4;
    		}
    
    		if (sc->sc_methods->ucom_open != NULL) {
    			error = sc->sc_methods->ucom_open(sc->sc_parent,
    			    sc->sc_portno);
    			if (error) {
    				ucom_cleanup(sc);
    				splx(s);
    				ucom_unlock(sc);
    				return (error);
    			}
    		}
    
    		ucom_status_change(sc);
    
    		ucomstartread(sc);
    		sc->sc_open = 1;
    	}
    	splx(s);
    	s = spltty();
    	ucom_unlock(sc);
    	tp = sc->sc_tty;
    	splx(s);
    
    	DPRINTF(("ucomopen: unit=%d, tp=%p\n", UCOMUNIT(dev), tp));
    
    	tp->t_dev = dev;
    	if (!ISSET(tp->t_state, TS_ISOPEN)) {
    		SET(tp->t_state, TS_WOPEN);
    		ttychars(tp);
    
    		/*
    		 * Initialize the termios status to the defaults.  Add in the
    		 * sticky bits from TIOCSFLAGS.
    		 */
    		t.c_ispeed = 0;
    		t.c_ospeed = TTYDEF_SPEED;
    		t.c_cflag = TTYDEF_CFLAG;
    		if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL))
    			SET(t.c_cflag, CLOCAL);
    		if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS))
    			SET(t.c_cflag, CRTSCTS);
    		if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF))
    			SET(t.c_cflag, MDMBUF);
    
    		/* Make sure ucomparam() will do something. */
    		tp->t_ospeed = 0;
    		(void) ucomparam(tp, &t);
    		tp->t_iflag = TTYDEF_IFLAG;
    		tp->t_oflag = TTYDEF_OFLAG;
    		tp->t_lflag = TTYDEF_LFLAG;
    
    		s = spltty();
    		ttsetwater(tp);
    
    		/*
    		 * Turn on DTR.  We must always do this, even if carrier is not
    		 * present, because otherwise we'd have to use TIOCSDTR
    		 * immediately after setting CLOCAL, which applications do not
    		 * expect.  We always assert DTR while the device is open
    		 * unless explicitly requested to deassert it.
    		 */
    		ucom_dtr(sc, 1);
    		/* When not using CRTSCTS, RTS follows DTR. */
    		if (!ISSET(t.c_cflag, CRTSCTS))
    			ucom_rts(sc, 1);
    
    		/* XXX CLR(sc->sc_rx_flags, RX_ANY_BLOCK);*/
    		ucom_hwiflow(sc);
    
    		if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR) || UCOMCUA(dev) ||
    		    ISSET(sc->sc_msr, UMSR_DCD) || ISSET(tp->t_cflag, MDMBUF))
    			SET(tp->t_state, TS_CARR_ON);
    		else
    			CLR(tp->t_state, TS_CARR_ON);
    	} else if (ISSET(tp->t_state, TS_XCLUDE) && suser(p) != 0)
    		return (EBUSY);
    	else
    		s = spltty();
    
    	if (UCOMCUA(dev)) {
    		if (ISSET(tp->t_state, TS_ISOPEN)) {
    			/* Someone is already dialed in */
    			splx(s);
    			return (EBUSY);
    		}
    		sc->sc_cua = 1;
    	} else {
    		/* tty (not cua) device, wait for carrier */
    		if (ISSET(flag, O_NONBLOCK)) {
    			if (sc->sc_cua) {
    				splx(s);
    				return (EBUSY);
    			}
    		} else {
    			while (sc->sc_cua || (!ISSET(tp->t_cflag, CLOCAL) &&
    			    !ISSET(tp->t_state, TS_CARR_ON))) {
    				SET(tp->t_state, TS_WOPEN);
    				error = ttysleep(tp, &tp->t_rawq,
    				    TTIPRI | PCATCH, ttopen);
    
    				if (usbd_is_dying(sc->sc_uparent)) {
    					splx(s);
    					return (EIO);
    				}
    
    				/*
    				 * If TS_WOPEN has been reset, that means the
    				 * cua device has been closed.  We don't want
    				 * to fail in that case, so just go around
    				 * again.
    				 */
    				if (error && ISSET(tp->t_state, TS_WOPEN)) {
    					CLR(tp->t_state, TS_WOPEN);
    					splx(s);
    					goto bad;
    				}
    			}
    		}
    	}
    	splx(s);
    
    	error = (*LINESW(tp, l_open))(dev, tp, p);
    	if (error)
    		goto bad;
    
    	return (0);
    
    fail_4:
    	if (sc->sc_bulkin_no != -1)
    		usbd_free_xfer(sc->sc_oxfer);
    	sc->sc_oxfer = NULL;
    fail_3:
    	usbd_free_xfer(sc->sc_ixfer);
    	sc->sc_ixfer = NULL;
    fail_2:
    	usbd_close_pipe(sc->sc_bulkout_pipe);
    	sc->sc_bulkout_pipe = NULL;
    fail_1:
    	usbd_close_pipe(sc->sc_bulkin_pipe);
    	sc->sc_bulkin_pipe = NULL;
    fail_0:
    	splx(s);
    	ucom_unlock(sc);
    	return (error);
    
    bad:
    	ucom_lock(sc);
    	ucom_cleanup(sc);
    	ucom_unlock(sc);
    
    	return (error);
    }
    
    int
    ucomclose(dev_t dev, int flag, int mode, struct proc *p)
    {
    	struct ucom_softc *sc = ucom_cd.cd_devs[UCOMUNIT(dev)];
    	int error;
    
    	if (sc == NULL || usbd_is_dying(sc->sc_uparent))
    		return (EIO);
    
    	DPRINTF(("ucomclose: unit=%d\n", UCOMUNIT(dev)));
    
    	sc->sc_refcnt++;
    	error = ucom_do_close(sc, flag, mode, p);
    	if (--sc->sc_refcnt < 0)
    		usb_detach_wakeup(&sc->sc_dev);
    
    	return (error);
    }
    
    int
    ucom_do_close(struct ucom_softc *sc, int flag, int mode, struct proc *p)
    {
    	struct tty *tp = sc->sc_tty;
    	int s;
    
    	if (!ISSET(tp->t_state, TS_ISOPEN))
    		return (0);
    
    	ucom_lock(sc);
    
    	(*LINESW(tp, l_close))(tp, flag, p);
    	s = spltty();
    	CLR(tp->t_state, TS_BUSY | TS_FLUSH);
    	sc->sc_cua = 0;
    	ttyclose(tp);
    	splx(s);
    	ucom_cleanup(sc);
    
    	if (sc->sc_methods->ucom_close != NULL)
    		sc->sc_methods->ucom_close(sc->sc_parent, sc->sc_portno);
    
    	ucom_unlock(sc);
    
    	return (0);
    }
    
    int
    ucomread(dev_t dev, struct uio *uio, int flag)
    {
    	struct ucom_softc *sc = ucom_cd.cd_devs[UCOMUNIT(dev)];
    	struct tty *tp;
    	int error;
    
    	if (sc == NULL || usbd_is_dying(sc->sc_uparent))
    		return (EIO);
    
    	if (sc->sc_error)
    		return (sc->sc_error);
    
    	sc->sc_refcnt++;
    	tp = sc->sc_tty;
    	error = (*LINESW(tp, l_read))(tp, uio, flag);
    	if (--sc->sc_refcnt < 0)
    		usb_detach_wakeup(&sc->sc_dev);
    	return (error);
    }
    
    int
    ucomwrite(dev_t dev, struct uio *uio, int flag)
    {
    	struct ucom_softc *sc = ucom_cd.cd_devs[UCOMUNIT(dev)];
    	struct tty *tp;
    	int error;
    
    	if (sc == NULL || usbd_is_dying(sc->sc_uparent))
    		return (EIO);
    
    	sc->sc_refcnt++;
    	tp = sc->sc_tty;
    	error = (*LINESW(tp, l_write))(tp, uio, flag);
    	if (--sc->sc_refcnt < 0)
    		usb_detach_wakeup(&sc->sc_dev);
    	return (error);
    }
    
    struct tty *
    ucomtty(dev_t dev)
    {
    	struct ucom_softc *sc = ucom_cd.cd_devs[UCOMUNIT(dev)];
    
    	/*
    	 * Return a pointer to our tty even if the device is dying
    	 * in order to properly close it in the detach routine.
    	 */
    	if (sc == NULL)
    		return (NULL);
    
    	return (sc->sc_tty);
    }
    
    int
    ucomioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
    {
    	struct ucom_softc *sc = ucom_cd.cd_devs[UCOMUNIT(dev)];
    	int error;
    
    	if (sc == NULL || usbd_is_dying(sc->sc_uparent))
    		return (EIO);
    
    	sc->sc_refcnt++;
    	error = ucom_do_ioctl(sc, cmd, data, flag, p);
    	if (--sc->sc_refcnt < 0)
    		usb_detach_wakeup(&sc->sc_dev);
    	return (error);
    }
    
    int
    ucom_do_ioctl(struct ucom_softc *sc, u_long cmd, caddr_t data,
    	      int flag, struct proc *p)
    {
    	struct tty *tp = sc->sc_tty;
    	int error;
    	int s;
    
    	DPRINTF(("ucomioctl: cmd=0x%08lx\n", cmd));
    
    	error = (*LINESW(tp, l_ioctl))(tp, cmd, data, flag, p);
    	if (error >= 0)
    		return (error);
    
    	error = ttioctl(tp, cmd, data, flag, p);
    	if (error >= 0)
    		return (error);
    
    	if (sc->sc_methods->ucom_ioctl != NULL) {
    		error = sc->sc_methods->ucom_ioctl(sc->sc_parent,
    			    sc->sc_portno, cmd, data, flag, p);
    		if (error != ENOTTY)
    			return (error);
    	}
    
    	error = 0;
    
    	DPRINTF(("ucomioctl: our cmd=0x%08lx\n", cmd));
    	s = spltty();
    
    	switch (cmd) {
    	case TIOCSBRK:
    		ucom_break(sc, 1);
    		break;
    
    	case TIOCCBRK:
    		ucom_break(sc, 0);
    		break;
    
    	case TIOCSDTR:
    		ucom_dtr(sc, 1);
    		break;
    
    	case TIOCCDTR:
    		ucom_dtr(sc, 0);
    		break;
    
    	case TIOCGFLAGS:
    		*(int *)data = sc->sc_swflags;
    		break;
    
    	case TIOCSFLAGS:
    		error = suser(p);
    		if (error)
    			break;
    		sc->sc_swflags = *(int *)data;
    		break;
    
    	case TIOCMSET:
    	case TIOCMBIS:
    	case TIOCMBIC:
    		tiocm_to_ucom(sc, cmd, *(int *)data);
    		break;
    
    	case TIOCMGET:
    		*(int *)data = ucom_to_tiocm(sc);
    		break;
    
    	default:
    		error = ENOTTY;
    		break;
    	}
    
    	splx(s);
    
    	return (error);
    }
    
    void
    tiocm_to_ucom(struct ucom_softc *sc, u_long how, int ttybits)
    {
    	u_char combits;
    
    	combits = 0;
    	if (ISSET(ttybits, TIOCM_DTR))
    		SET(combits, UMCR_DTR);
    	if (ISSET(ttybits, TIOCM_RTS))
    		SET(combits, UMCR_RTS);
    
    	switch (how) {
    	case TIOCMBIC:
    		CLR(sc->sc_mcr, combits);
    		break;
    
    	case TIOCMBIS:
    		SET(sc->sc_mcr, combits);
    		break;
    
    	case TIOCMSET:
    		CLR(sc->sc_mcr, UMCR_DTR | UMCR_RTS);
    		SET(sc->sc_mcr, combits);
    		break;
    	}
    
    	if (how == TIOCMSET || ISSET(combits, UMCR_DTR))
    		ucom_dtr(sc, (sc->sc_mcr & UMCR_DTR) != 0);
    	if (how == TIOCMSET || ISSET(combits, UMCR_RTS))
    		ucom_rts(sc, (sc->sc_mcr & UMCR_RTS) != 0);
    }
    
    int
    ucom_to_tiocm(struct ucom_softc *sc)
    {
    	u_char combits;
    	int ttybits = 0;
    
    	combits = sc->sc_mcr;
    	if (ISSET(combits, UMCR_DTR))
    		SET(ttybits, TIOCM_DTR);
    	if (ISSET(combits, UMCR_RTS))
    		SET(ttybits, TIOCM_RTS);
    
    	combits = sc->sc_msr;
    	if (ISSET(combits, UMSR_DCD))
    		SET(ttybits, TIOCM_CD);
    	if (ISSET(combits, UMSR_CTS))
    		SET(ttybits, TIOCM_CTS);
    	if (ISSET(combits, UMSR_DSR))
    		SET(ttybits, TIOCM_DSR);
    	if (ISSET(combits, UMSR_RI | UMSR_TERI))
    		SET(ttybits, TIOCM_RI);
    
    #if 0
    XXX;
    	if (sc->sc_ier != 0)
    		SET(ttybits, TIOCM_LE);
    #endif
    
    	return (ttybits);
    }
    
    void
    ucom_break(struct ucom_softc *sc, int onoff)
    {
    	DPRINTF(("ucom_break: onoff=%d\n", onoff));
    
    	if (sc->sc_methods->ucom_set != NULL)
    		sc->sc_methods->ucom_set(sc->sc_parent, sc->sc_portno,
    		    UCOM_SET_BREAK, onoff);
    }
    
    void
    ucom_dtr(struct ucom_softc *sc, int onoff)
    {
    	DPRINTF(("ucom_dtr: onoff=%d\n", onoff));
    
    	if (sc->sc_methods->ucom_set != NULL)
    		sc->sc_methods->ucom_set(sc->sc_parent, sc->sc_portno,
    		    UCOM_SET_DTR, onoff);
    }
    
    void
    ucom_rts(struct ucom_softc *sc, int onoff)
    {
    	DPRINTF(("ucom_rts: onoff=%d\n", onoff));
    
    	if (sc->sc_methods->ucom_set != NULL)
    		sc->sc_methods->ucom_set(sc->sc_parent, sc->sc_portno,
    		    UCOM_SET_RTS, onoff);
    }
    
    void
    ucom_status_change(struct ucom_softc *sc)
    {
    	struct tty *tp = sc->sc_tty;
    	u_char old_msr;
    
    	if (sc->sc_methods->ucom_get_status != NULL) {
    		old_msr = sc->sc_msr;
    		sc->sc_methods->ucom_get_status(sc->sc_parent, sc->sc_portno,
    		    &sc->sc_lsr, &sc->sc_msr);
    
    		ttytstamp(tp, old_msr & UMSR_CTS, sc->sc_msr & UMSR_CTS,
    		    old_msr & UMSR_DCD, sc->sc_msr & UMSR_DCD);
    
    		if (ISSET((sc->sc_msr ^ old_msr), UMSR_DCD))
    			(*LINESW(tp, l_modem))(tp,
    			    ISSET(sc->sc_msr, UMSR_DCD));
    	} else {
    		sc->sc_lsr = 0;
    		sc->sc_msr = 0;
    	}
    }
    
    int
    ucomparam(struct tty *tp, struct termios *t)
    {
    	struct ucom_softc *sc = ucom_cd.cd_devs[UCOMUNIT(tp->t_dev)];
    	int error;
    
    	if (sc == NULL || usbd_is_dying(sc->sc_uparent))
    		return (EIO);
    
    	/* Check requested parameters. */
    	if (t->c_ispeed && t->c_ispeed != t->c_ospeed)
    		return (EINVAL);
    
    	/*
    	 * For the console, always force CLOCAL and !HUPCL, so that the port
    	 * is always active.
    	 */
    	if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR)) {
    		SET(t->c_cflag, CLOCAL);
    		CLR(t->c_cflag, HUPCL);
    	}
    
    	/*
    	 * If there were no changes, don't do anything.  This avoids dropping
    	 * input and improves performance when all we did was frob things like
    	 * VMIN and VTIME.
    	 */
    	if (tp->t_ospeed == t->c_ospeed &&
    	    tp->t_cflag == t->c_cflag)
    		return (0);
    
    	/* XXX lcr = ISSET(sc->sc_lcr, LCR_SBREAK) | cflag2lcr(t->c_cflag); */
    
    	/* And copy to tty. */
    	tp->t_ispeed = 0;
    	tp->t_ospeed = t->c_ospeed;
    	tp->t_cflag = t->c_cflag;
    
    	/*
    	 * When not using CRTSCTS, RTS follows DTR.
    	 * This assumes that the ucom_param() call will enable these signals
    	 * for real.
    	 */
    	if (!ISSET(t->c_cflag, CRTSCTS))
    		sc->sc_mcr = UMCR_DTR | UMCR_RTS;
    	else
    		sc->sc_mcr = UMCR_DTR;
    
    	if (sc->sc_methods->ucom_param != NULL) {
    		error = sc->sc_methods->ucom_param(sc->sc_parent, sc->sc_portno,
    			    t);
    		if (error)
    			return (error);
    	}
    
    	/* XXX worry about CHWFLOW */
    
    	/*
    	 * Update the tty layer's idea of the carrier bit, in case we changed
    	 * CLOCAL or MDMBUF.  We don't hang up here; we only do that by
    	 * explicit request.
    	 */
    	DPRINTF(("ucomparam: l_modem\n"));
    	(void) (*LINESW(tp, l_modem))(tp, 1 /* XXX carrier */ );
    
    #if 0
    XXX what if the hardware is not open
    	if (!ISSET(t->c_cflag, CHWFLOW)) {
    		if (sc->sc_tx_stopped) {
    			sc->sc_tx_stopped = 0;
    			ucomstart(tp);
    		}
    	}
    #endif
    
    	return (0);
    }
    
    /*
     * (un)block input via hw flowcontrol
     */
    void
    ucom_hwiflow(struct ucom_softc *sc)
    {
    	DPRINTF(("ucom_hwiflow:\n"));
    #if 0
    XXX
    	bus_space_tag_t iot = sc->sc_iot;
    	bus_space_handle_t ioh = sc->sc_ioh;
    
    	if (sc->sc_mcr_rts == 0)
    		return;
    
    	if (ISSET(sc->sc_rx_flags, RX_ANY_BLOCK)) {
    		CLR(sc->sc_mcr, sc->sc_mcr_rts);
    		CLR(sc->sc_mcr_active, sc->sc_mcr_rts);
    	} else {
    		SET(sc->sc_mcr, sc->sc_mcr_rts);
    		SET(sc->sc_mcr_active, sc->sc_mcr_rts);
    	}
    	bus_space_write_1(iot, ioh, com_mcr, sc->sc_mcr_active);
    #endif
    }
    
    void
    ucomstart(struct tty *tp)
    {
    	struct ucom_softc *sc = ucom_cd.cd_devs[UCOMUNIT(tp->t_dev)];
    	usbd_status err;
    	int s;
    	u_char *data;
    	int cnt;
    
    	if (sc == NULL || usbd_is_dying(sc->sc_uparent))
    		return;
    
    	s = spltty();
    	if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP)) {
    		DPRINTFN(4,("ucomstart: no go, state=0x%x\n", tp->t_state));
    		goto out;
    	}
    	if (sc->sc_tx_stopped)
    		goto out;
    
    	ttwakeupwr(tp);
    	if (tp->t_outq.c_cc == 0)
    		goto out;
    
    	/* Grab the first contiguous region of buffer space. */
    	data = tp->t_outq.c_cf;
    	cnt = ndqb(&tp->t_outq, 0);
    
    	if (cnt == 0) {
    		DPRINTF(("ucomstart: cnt==0\n"));
    		goto out;
    	}
    
    	SET(tp->t_state, TS_BUSY);
    
    	if (cnt > sc->sc_obufsize) {
    		DPRINTF(("ucomstart: big buffer %d chars\n", cnt));
    		cnt = sc->sc_obufsize;
    	}
    	if (sc->sc_methods->ucom_write != NULL)
    		sc->sc_methods->ucom_write(sc->sc_parent, sc->sc_portno,
    					   sc->sc_obuf, data, &cnt);
    	else
    		memcpy(sc->sc_obuf, data, cnt);
    
    	DPRINTFN(4,("ucomstart: %d chars\n", cnt));
    #ifdef DIAGNOSTIC
    	if (sc->sc_oxfer == NULL) {
    		printf("ucomstart: null oxfer\n");
    		goto out;
    	}
    #endif
    	if (sc->sc_bulkout_pipe != NULL) {
    		usbd_setup_xfer(sc->sc_oxfer, sc->sc_bulkout_pipe,
    		    (void *)sc, sc->sc_obuf, cnt,
    		    USBD_NO_COPY, USBD_NO_TIMEOUT, ucomwritecb);
    	} else {
    		usbd_setup_xfer(sc->sc_oxfer, sc->sc_opipe,
    		    (void *)sc, sc->sc_obuf, cnt,
    		    USBD_NO_COPY, USBD_NO_TIMEOUT, ucomwritecb);
    	}
    	/* What can we do on error? */
    	err = usbd_transfer(sc->sc_oxfer);
    #ifdef DIAGNOSTIC
    	if (err != USBD_IN_PROGRESS)
    		printf("ucomstart: err=%s\n", usbd_errstr(err));
    #endif
    
    out:
    	splx(s);
    }
    
    int
    ucomstop(struct tty *tp, int flag)
    {
    	DPRINTF(("ucomstop: flag=%d\n", flag));
    #if 0
    	/*struct ucom_softc *sc = ucom_cd.cd_devs[UCOMUNIT(tp->t_dev)];*/
    	int s;
    
    	s = spltty();
    	if (ISSET(tp->t_state, TS_BUSY)) {
    		DPRINTF(("ucomstop: XXX\n"));
    		/* sc->sc_tx_stopped = 1; */
    		if (!ISSET(tp->t_state, TS_TTSTOP))
    			SET(tp->t_state, TS_FLUSH);
    	}
    	splx(s);
    #endif
    	return (0);
    }
    
    void
    ucomwritecb(struct usbd_xfer *xfer, void *p, usbd_status status)
    {
    	struct ucom_softc *sc = (struct ucom_softc *)p;
    	struct tty *tp = sc->sc_tty;
    	u_int32_t cc;
    	int s;
    
    	DPRINTFN(5,("ucomwritecb: %p %p status=%d\n", xfer, p, status));
    
    	if (status == USBD_CANCELLED || usbd_is_dying(sc->sc_uparent))
    		goto error;
    
    	if (sc->sc_bulkin_pipe != NULL) {
    		if (status) {
    			usbd_clear_endpoint_stall_async(sc->sc_bulkin_pipe);
    			/* XXX we should restart after some delay. */
    			goto error;
    		}
    		usbd_get_xfer_status(xfer, NULL, NULL, &cc, NULL);
    	} else {
    		usbd_get_xfer_status(xfer, NULL, NULL, &cc, NULL);
    		// XXX above gives me wrong cc, no?
    	}
    
    	DPRINTFN(5,("ucomwritecb: cc=%d\n", cc));
    	/* convert from USB bytes to tty bytes */
    	cc -= sc->sc_opkthdrlen;
    
    	s = spltty();
    	CLR(tp->t_state, TS_BUSY);
    	if (ISSET(tp->t_state, TS_FLUSH))
    		CLR(tp->t_state, TS_FLUSH);
    	else
    		ndflush(&tp->t_outq, cc);
    	(*LINESW(tp, l_start))(tp);
    	splx(s);
    	return;
    
    error:
    	s = spltty();
    	CLR(tp->t_state, TS_BUSY);
    	splx(s);
    }
    
    usbd_status
    ucomstartread(struct ucom_softc *sc)
    {
    	usbd_status err;
    
    	DPRINTFN(5,("ucomstartread: start\n"));
    #ifdef DIAGNOSTIC
    	if (sc->sc_ixfer == NULL) {
    		DPRINTF(("ucomstartread: null ixfer\n"));
    		return (USBD_INVAL);
    	}
    #endif
    
    	if (sc->sc_bulkin_pipe != NULL) {
    		usbd_setup_xfer(sc->sc_ixfer, sc->sc_bulkin_pipe,
    			(void *)sc,
    			sc->sc_ibuf, sc->sc_ibufsize,
    			USBD_SHORT_XFER_OK | USBD_NO_COPY,
    			USBD_NO_TIMEOUT, ucomreadcb);
    		err = usbd_transfer(sc->sc_ixfer);
    		if (err != USBD_IN_PROGRESS) {
    			DPRINTF(("ucomstartread: err=%s\n", usbd_errstr(err)));
    			return (err);
    		}
    	}
    
    	return (USBD_NORMAL_COMPLETION);
    }
    
    void
    ucomreadcb(struct usbd_xfer *xfer, void *p, usbd_status status)
    {
    	struct ucom_softc *sc = (struct ucom_softc *)p;
    	struct tty *tp = sc->sc_tty;
    	int (*rint)(int c, struct tty *tp) = LINESW(tp, l_rint);
    	usbd_status err;
    	u_int32_t cc;
    	u_char *cp;
    	int s;
    
    	DPRINTFN(5,("ucomreadcb: status=%d\n", status));
    
    	if (status == USBD_CANCELLED || status == USBD_IOERROR ||
    	    usbd_is_dying(sc->sc_uparent)) {
    		DPRINTF(("ucomreadcb: dying\n"));
    		/* Send something to wake upper layer */
    		sc->sc_error = EIO;
    		s = spltty();
    		(*rint)('\n', tp);
    		ttwakeup(tp);
    		splx(s);
    		return;
    	}
    
    	if (status) {
    		if (sc->sc_bulkin_pipe != NULL) {
    			usbd_clear_endpoint_stall_async(sc->sc_bulkin_pipe);
    			/* XXX we should restart after some delay. */
    			return;
    		}
    	}
    
    	usbd_get_xfer_status(xfer, NULL, (void *)&cp, &cc, NULL);
    	DPRINTFN(5,("ucomreadcb: got %d chars, tp=%p\n", cc, tp));
    	if (sc->sc_methods->ucom_read != NULL)
    		sc->sc_methods->ucom_read(sc->sc_parent, sc->sc_portno,
    					  &cp, &cc);
    
    	s = spltty();
    	/* Give characters to tty layer. */
    	while (cc-- > 0) {
    		DPRINTFN(7,("ucomreadcb: char=0x%02x\n", *cp));
    		if ((*rint)(*cp++, tp) == -1) {
    			/* XXX what should we do? */
    			printf("%s: lost %d chars\n", sc->sc_dev.dv_xname,
    			       cc);
    			break;
    		}
    	}
    	splx(s);
    
    	err = ucomstartread(sc);
    	if (err) {
    		printf("%s: read start failed\n", sc->sc_dev.dv_xname);
    		/* XXX what should we dow now? */
    	}
    }
    
    void
    ucom_cleanup(struct ucom_softc *sc)
    {
    	DPRINTF(("ucom_cleanup: closing pipes\n"));
    
    	sc->sc_open = 0;
    
    	ucom_shutdown(sc);
    	if (sc->sc_bulkin_pipe != NULL) {
    		usbd_close_pipe(sc->sc_bulkin_pipe);
    		sc->sc_bulkin_pipe = NULL;
    	}
    	if (sc->sc_bulkout_pipe != NULL) {
    		usbd_close_pipe(sc->sc_bulkout_pipe);
    		sc->sc_bulkout_pipe = NULL;
    	}
    	if (sc->sc_ixfer != NULL) {
    		if (sc->sc_bulkin_no != -1) {
    			usbd_free_buffer(sc->sc_ixfer);
    			sc->sc_ibuf = NULL;
    			usbd_free_xfer(sc->sc_ixfer);
    		}
    		sc->sc_ixfer = NULL;
    	}
    	if (sc->sc_oxfer != NULL) {
    		usbd_free_buffer(sc->sc_oxfer);
    		sc->sc_obuf = NULL;
    		if (sc->sc_bulkin_no != -1)
    			usbd_free_xfer(sc->sc_oxfer);
    		sc->sc_oxfer = NULL;
    	}
    }
    
    /*
     * Update ucom names for export by sysctl.
     */
    char *
    sysctl_ucominit(void)
    {
    	static char *ucoms = NULL;
    	static size_t ucomslen = 0;
    	char name[64];	/* dv_xname + ":usb000.000.00000.000," */
    	struct ucom_softc *sc;
    	int rslt;
    	unsigned int unit;
    	uint32_t route;
    	uint8_t bus, ifaceno;
    
    	KERNEL_ASSERT_LOCKED();
    
    	if (rw_enter(&sysctl_ucomlock, RW_WRITE|RW_INTR) != 0)
    		return NULL;
    
    	if (ucoms == NULL || ucom_change) {
    		free(ucoms, M_SYSCTL, ucomslen);
    		ucomslen = ucom_cd.cd_ndevs * sizeof(name);
    		ucoms = malloc(ucomslen, M_SYSCTL, M_WAITOK | M_ZERO);
    		for (unit = 0; unit < ucom_cd.cd_ndevs; unit++) {
    			sc = ucom_cd.cd_devs[unit];
    			if (sc == NULL || sc->sc_iface == NULL)
    				continue;
    			if (usbd_get_location(sc->sc_uparent, sc->sc_iface,
    			    &bus, &route, &ifaceno) == -1)
    				continue;
    			rslt = snprintf(name, sizeof(name),
    			    "%s:usb%u.%u.%05x.%u,", sc->sc_dev.dv_xname, bus,
    			    ROUTEROOTPORT(route), ROUTESTRING(route), ifaceno);
    			if (rslt < sizeof(name) && (strlen(ucoms) + rslt) <
    			    ucomslen)
    				strlcat(ucoms, name, ucomslen);
    		}
    	}
    
    	/* Remove trailing ','. */
    	if (strlen(ucoms))
    		ucoms[strlen(ucoms) - 1] = '\0';
    
    	rw_exit_write(&sysctl_ucomlock);
    
    	return ucoms;
    }
    #endif	/* NUCOM > 0 */
    
    int
    ucomprint(void *aux, const char *pnp)
    {
    	struct ucom_attach_args *uca = aux;
    
    	if (pnp)
    		printf("ucom at %s", pnp);
    	if (uca->portno != UCOM_UNK_PORTNO)
    		printf(" portno %d", uca->portno);
    	return (UNCONF);
    }
    
    int
    ucomsubmatch(struct device *parent, void *match, void *aux)
    {
            struct ucom_attach_args *uca = aux;
            struct cfdata *cf = match;
    
    	if (uca->portno != UCOM_UNK_PORTNO &&
    	    cf->ucomcf_portno != UCOM_UNK_PORTNO &&
    	    cf->ucomcf_portno != uca->portno)
    		return (0);
    	return ((*cf->cf_attach->ca_match)(parent, cf, aux));
    }