freebsd-skq/sys/dev/uart/uart_tty.c
marcel c41873e078 In uart_tty_outwakeup(), check CTS/RTS flow control settings and
prevent sending data when CTS is de-asserted.
In uart_tty_intr(), call uart_tty_outwakeup() when the CTS signal
changed, knowing that uart_tty_outwakeup() will do the right
thing for flow control. This avoids redundant conditionals.

PR:		kern/148644
Submitted by:	John Wehle <john@feith.com>
MFC after:	3 days
2011-01-24 18:34:16 +00:00

397 lines
8.9 KiB
C

/*-
* Copyright (c) 2003 Marcel Moolenaar
* All rights reserved.
*
* 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 AUTHOR ``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 AUTHOR 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/conf.h>
#include <sys/cons.h>
#include <sys/fcntl.h>
#include <sys/interrupt.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/reboot.h>
#include <machine/bus.h>
#include <sys/rman.h>
#include <sys/tty.h>
#include <machine/resource.h>
#include <machine/stdarg.h>
#include <dev/uart/uart.h>
#include <dev/uart/uart_bus.h>
#include <dev/uart/uart_cpu.h>
#include "uart_if.h"
static cn_probe_t uart_cnprobe;
static cn_init_t uart_cninit;
static cn_term_t uart_cnterm;
static cn_getc_t uart_cngetc;
static cn_putc_t uart_cnputc;
CONSOLE_DRIVER(uart);
static struct uart_devinfo uart_console;
static void
uart_cnprobe(struct consdev *cp)
{
cp->cn_pri = CN_DEAD;
KASSERT(uart_console.cookie == NULL, ("foo"));
if (uart_cpu_getdev(UART_DEV_CONSOLE, &uart_console))
return;
if (uart_probe(&uart_console))
return;
strlcpy(cp->cn_name, uart_driver_name, sizeof(cp->cn_name));
cp->cn_pri = (boothowto & RB_SERIAL) ? CN_REMOTE : CN_NORMAL;
cp->cn_arg = &uart_console;
}
static void
uart_cninit(struct consdev *cp)
{
struct uart_devinfo *di;
/*
* Yedi trick: we need to be able to define cn_dev before we go
* single- or multi-user. The problem is that we don't know at
* this time what the device will be. Hence, we need to link from
* the uart_devinfo to the consdev that corresponds to it so that
* we can define cn_dev in uart_bus_attach() when we find the
* device during bus enumeration. That's when we'll know what the
* the unit number will be.
*/
di = cp->cn_arg;
KASSERT(di->cookie == NULL, ("foo"));
di->cookie = cp;
di->type = UART_DEV_CONSOLE;
uart_add_sysdev(di);
uart_init(di);
}
static void
uart_cnterm(struct consdev *cp)
{
uart_term(cp->cn_arg);
}
static void
uart_cnputc(struct consdev *cp, int c)
{
uart_putc(cp->cn_arg, c);
}
static int
uart_cngetc(struct consdev *cp)
{
return (uart_poll(cp->cn_arg));
}
static int
uart_tty_open(struct tty *tp)
{
struct uart_softc *sc;
sc = tty_softc(tp);
if (sc == NULL || sc->sc_leaving)
return (ENXIO);
sc->sc_opened = 1;
return (0);
}
static void
uart_tty_close(struct tty *tp)
{
struct uart_softc *sc;
sc = tty_softc(tp);
if (sc == NULL || sc->sc_leaving || !sc->sc_opened)
return;
if (sc->sc_hwiflow)
UART_IOCTL(sc, UART_IOCTL_IFLOW, 0);
if (sc->sc_hwoflow)
UART_IOCTL(sc, UART_IOCTL_OFLOW, 0);
if (sc->sc_sysdev == NULL)
UART_SETSIG(sc, SER_DDTR | SER_DRTS);
wakeup(sc);
sc->sc_opened = 0;
return;
}
static void
uart_tty_outwakeup(struct tty *tp)
{
struct uart_softc *sc;
sc = tty_softc(tp);
if (sc == NULL || sc->sc_leaving)
return;
if (sc->sc_txbusy)
return;
/*
* Respect RTS/CTS (output) flow control if enabled and not already
* handled by hardware.
*/
if ((tp->t_termios.c_cflag & CCTS_OFLOW) && !sc->sc_hwoflow &&
!(sc->sc_hwsig & SER_CTS))
return;
sc->sc_txdatasz = ttydisc_getc(tp, sc->sc_txbuf, sc->sc_txfifosz);
if (sc->sc_txdatasz != 0)
UART_TRANSMIT(sc);
}
static void
uart_tty_inwakeup(struct tty *tp)
{
struct uart_softc *sc;
sc = tty_softc(tp);
if (sc == NULL || sc->sc_leaving)
return;
if (sc->sc_isquelch) {
if ((tp->t_termios.c_cflag & CRTS_IFLOW) && !sc->sc_hwiflow)
UART_SETSIG(sc, SER_DRTS|SER_RTS);
sc->sc_isquelch = 0;
uart_sched_softih(sc, SER_INT_RXREADY);
}
}
static int
uart_tty_ioctl(struct tty *tp, u_long cmd, caddr_t data, struct thread *td)
{
struct uart_softc *sc;
sc = tty_softc(tp);
switch (cmd) {
case TIOCSBRK:
UART_IOCTL(sc, UART_IOCTL_BREAK, 1);
return (0);
case TIOCCBRK:
UART_IOCTL(sc, UART_IOCTL_BREAK, 0);
return (0);
default:
return pps_ioctl(cmd, data, &sc->sc_pps);
}
}
static int
uart_tty_param(struct tty *tp, struct termios *t)
{
struct uart_softc *sc;
int databits, parity, stopbits;
sc = tty_softc(tp);
if (sc == NULL || sc->sc_leaving)
return (ENODEV);
if (t->c_ispeed != t->c_ospeed && t->c_ospeed != 0)
return (EINVAL);
/* Fixate certain parameters for system devices. */
if (sc->sc_sysdev != NULL) {
t->c_ispeed = t->c_ospeed = sc->sc_sysdev->baudrate;
t->c_cflag |= CLOCAL;
t->c_cflag &= ~HUPCL;
}
if (t->c_ospeed == 0) {
UART_SETSIG(sc, SER_DDTR | SER_DRTS);
return (0);
}
switch (t->c_cflag & CSIZE) {
case CS5: databits = 5; break;
case CS6: databits = 6; break;
case CS7: databits = 7; break;
default: databits = 8; break;
}
stopbits = (t->c_cflag & CSTOPB) ? 2 : 1;
if (t->c_cflag & PARENB)
parity = (t->c_cflag & PARODD) ? UART_PARITY_ODD
: UART_PARITY_EVEN;
else
parity = UART_PARITY_NONE;
if (UART_PARAM(sc, t->c_ospeed, databits, stopbits, parity) != 0)
return (EINVAL);
UART_SETSIG(sc, SER_DDTR | SER_DTR);
/* Set input flow control state. */
if (!sc->sc_hwiflow) {
if ((t->c_cflag & CRTS_IFLOW) && sc->sc_isquelch)
UART_SETSIG(sc, SER_DRTS);
else
UART_SETSIG(sc, SER_DRTS | SER_RTS);
} else
UART_IOCTL(sc, UART_IOCTL_IFLOW, (t->c_cflag & CRTS_IFLOW));
/* Set output flow control state. */
if (sc->sc_hwoflow)
UART_IOCTL(sc, UART_IOCTL_OFLOW, (t->c_cflag & CCTS_OFLOW));
return (0);
}
static int
uart_tty_modem(struct tty *tp, int biton, int bitoff)
{
struct uart_softc *sc;
sc = tty_softc(tp);
if (biton != 0 || bitoff != 0)
UART_SETSIG(sc, SER_DELTA(bitoff|biton) | biton);
return (sc->sc_hwsig);
}
void
uart_tty_intr(void *arg)
{
struct uart_softc *sc = arg;
struct tty *tp;
int c, err = 0, pend, sig, xc;
if (sc->sc_leaving)
return;
pend = atomic_readandclear_32(&sc->sc_ttypend);
if (!(pend & SER_INT_MASK))
return;
tp = sc->sc_u.u_tty.tp;
tty_lock(tp);
if (pend & SER_INT_RXREADY) {
while (!uart_rx_empty(sc) && !sc->sc_isquelch) {
xc = uart_rx_peek(sc);
c = xc & 0xff;
if (xc & UART_STAT_FRAMERR)
err |= TRE_FRAMING;
if (xc & UART_STAT_OVERRUN)
err |= TRE_OVERRUN;
if (xc & UART_STAT_PARERR)
err |= TRE_PARITY;
if (ttydisc_rint(tp, c, err) != 0) {
sc->sc_isquelch = 1;
if ((tp->t_termios.c_cflag & CRTS_IFLOW) &&
!sc->sc_hwiflow)
UART_SETSIG(sc, SER_DRTS);
} else
uart_rx_next(sc);
}
}
if (pend & SER_INT_BREAK)
ttydisc_rint(tp, 0, TRE_BREAK);
if (pend & SER_INT_SIGCHG) {
sig = pend & SER_INT_SIGMASK;
if (sig & SER_DDCD)
ttydisc_modem(tp, sig & SER_DCD);
if (sig & SER_DCTS)
uart_tty_outwakeup(tp);
}
if (pend & SER_INT_TXIDLE)
uart_tty_outwakeup(tp);
ttydisc_rint_done(tp);
tty_unlock(tp);
}
static void
uart_tty_free(void *arg)
{
/*
* XXX: uart(4) could reuse the device unit number before it is
* being freed by the TTY layer. We should use this hook to free
* the device unit number, but unfortunately newbus does not
* seem to support such a construct.
*/
}
static struct ttydevsw uart_tty_class = {
.tsw_flags = TF_INITLOCK|TF_CALLOUT,
.tsw_open = uart_tty_open,
.tsw_close = uart_tty_close,
.tsw_outwakeup = uart_tty_outwakeup,
.tsw_inwakeup = uart_tty_inwakeup,
.tsw_ioctl = uart_tty_ioctl,
.tsw_param = uart_tty_param,
.tsw_modem = uart_tty_modem,
.tsw_free = uart_tty_free,
};
int
uart_tty_attach(struct uart_softc *sc)
{
struct tty *tp;
int unit;
sc->sc_u.u_tty.tp = tp = tty_alloc(&uart_tty_class, sc);
unit = device_get_unit(sc->sc_dev);
if (sc->sc_sysdev != NULL && sc->sc_sysdev->type == UART_DEV_CONSOLE) {
sprintf(((struct consdev *)sc->sc_sysdev->cookie)->cn_name,
"ttyu%r", unit);
tty_init_console(tp, 0);
}
swi_add(&tty_intr_event, uart_driver_name, uart_tty_intr, sc, SWI_TTY,
INTR_TYPE_TTY, &sc->sc_softih);
tty_makedev(tp, NULL, "u%r", unit);
return (0);
}
int
uart_tty_detach(struct uart_softc *sc)
{
struct tty *tp;
tp = sc->sc_u.u_tty.tp;
tty_lock(tp);
swi_remove(sc->sc_softih);
tty_rel_gone(tp);
return (0);
}