Author: shurd Date: Wed Jun 12 18:07:04 2019 New Revision: 348999 URL: https://svnweb.freebsd.org/changeset/base/348999
Log: Some devices take undesired actions when RTS and DTR are asserted. Some development boards for example will reset on DTR, and some radio interfaces will transmit on RTS. This patch allows "stty -f /dev/ttyu9.init -rtsdtr" to prevent RTS and DTR from being asserted on open(), allowing these devices to be used without problems. Reviewed by: imp Differential Revision: https://reviews.freebsd.org/D20031 Modified: head/bin/stty/modes.c head/bin/stty/print.c head/bin/stty/stty.1 head/share/man/man4/termios.4 head/sys/dev/uart/uart_tty.c head/sys/dev/usb/serial/umcs.c head/sys/dev/usb/serial/usb_serial.c head/sys/kern/tty.c head/sys/sys/_termios.h Modified: head/bin/stty/modes.c ============================================================================== --- head/bin/stty/modes.c Wed Jun 12 16:49:01 2019 (r348998) +++ head/bin/stty/modes.c Wed Jun 12 18:07:04 2019 (r348999) @@ -91,6 +91,8 @@ static const struct modes cmodes[] = { { "-rtsflow", 0, CRTS_IFLOW }, { "mdmbuf", MDMBUF, 0 }, { "-mdmbuf", 0, MDMBUF }, + { "rtsdtr", 0, CNO_RTSDTR }, + { "-rtsdtr", CNO_RTSDTR, 0 }, { NULL, 0, 0 }, }; Modified: head/bin/stty/print.c ============================================================================== --- head/bin/stty/print.c Wed Jun 12 16:49:01 2019 (r348998) +++ head/bin/stty/print.c Wed Jun 12 18:07:04 2019 (r348999) @@ -184,6 +184,12 @@ print(struct termios *tp, struct winsize *wp, int ldis put("-dsrflow", CDSR_OFLOW, 0); put("-dtrflow", CDTR_IFLOW, 0); put("-mdmbuf", MDMBUF, 0); /* XXX mdmbuf == dtrflow */ + if (on(CNO_RTSDTR)) + bput("-rtsdtr"); + else { + if (fmt >= BSD) + bput("rtsdtr"); + } /* special control characters */ cc = tp->c_cc; Modified: head/bin/stty/stty.1 ============================================================================== --- head/bin/stty/stty.1 Wed Jun 12 16:49:01 2019 (r348998) +++ head/bin/stty/stty.1 Wed Jun 12 18:07:04 2019 (r348999) @@ -145,6 +145,8 @@ Assume a line without (with) modem control. .It Cm crtscts Pq Fl crtscts Enable (disable) RTS/CTS flow control. +.It Cm rtsdtr Pq Fl -rtsdtr +Enable (disable) asserting RTS/DTR on open. .El .Ss Input Modes: This corresponds to the c_iflag in the termios structure. Modified: head/share/man/man4/termios.4 ============================================================================== --- head/share/man/man4/termios.4 Wed Jun 12 16:49:01 2019 (r348998) +++ head/share/man/man4/termios.4 Wed Jun 12 18:07:04 2019 (r348999) @@ -1185,6 +1185,8 @@ flow control of output */ /* RTS flow control of input */ .It Dv MDMBUF /* flow control output via Carrier */ +.It Dv CNO_RTSDTR +/* Do not assert RTS or DTR automatically */ .El .Pp The @@ -1266,6 +1268,12 @@ If .Dv MDMBUF is set then output flow control is controlled by the state of Carrier Detect. +.Pp +If +.Dv CNO_RTSDTR +is set then the RTS and DTR lines will not be asserted when the device +is opened. +As a result, this flag is only useful on initial-state devices. .Pp If the object for which the control modes are set is not an asynchronous serial connection, some of the modes may be ignored; for example, if an Modified: head/sys/dev/uart/uart_tty.c ============================================================================== --- head/sys/dev/uart/uart_tty.c Wed Jun 12 16:49:01 2019 (r348998) +++ head/sys/dev/uart/uart_tty.c Wed Jun 12 18:07:04 2019 (r348999) @@ -285,13 +285,16 @@ uart_tty_param(struct tty *tp, struct termios *t) parity = UART_PARITY_NONE; if (UART_PARAM(sc, t->c_ospeed, databits, stopbits, parity) != 0) return (EINVAL); - UART_SETSIG(sc, SER_DDTR | SER_DTR); + if ((t->c_cflag & CNO_RTSDTR) == 0) + 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 { + if ((t->c_cflag & CNO_RTSDTR) == 0) + UART_SETSIG(sc, SER_DRTS | SER_RTS); + } } else UART_IOCTL(sc, UART_IOCTL_IFLOW, (t->c_cflag & CRTS_IFLOW)); /* Set output flow control state. */ Modified: head/sys/dev/usb/serial/umcs.c ============================================================================== --- head/sys/dev/usb/serial/umcs.c Wed Jun 12 16:49:01 2019 (r348998) +++ head/sys/dev/usb/serial/umcs.c Wed Jun 12 18:07:04 2019 (r348999) @@ -499,7 +499,9 @@ umcs7840_cfg_open(struct ucom_softc *ucom) * Enable DTR/RTS on modem control, enable modem interrupts -- * documented */ - sc->sc_ports[pn].sc_mcr = MCS7840_UART_MCR_DTR | MCS7840_UART_MCR_RTS | MCS7840_UART_MCR_IE; + sc->sc_ports[pn].sc_mcr = MCS7840_UART_MCR_IE; + if (ucom->sc_tty == NULL || (ucom->sc_tty->t_termios.c_cflag & CNO_RTSDTR) == 0) + sc->sc_ports[pn].sc_mcr |= MCS7840_UART_MCR_DTR | MCS7840_UART_MCR_RTS; if (umcs7840_set_UART_reg_sync(sc, pn, MCS7840_UART_REG_MCR, sc->sc_ports[pn].sc_mcr)) return; Modified: head/sys/dev/usb/serial/usb_serial.c ============================================================================== --- head/sys/dev/usb/serial/usb_serial.c Wed Jun 12 16:49:01 2019 (r348998) +++ head/sys/dev/usb/serial/usb_serial.c Wed Jun 12 18:07:04 2019 (r348999) @@ -796,7 +796,8 @@ ucom_open(struct tty *tp) &sc->sc_start_task[0].hdr, &sc->sc_start_task[1].hdr); - ucom_modem(tp, SER_DTR | SER_RTS, 0); + if (sc->sc_tty == NULL || (sc->sc_tty->t_termios.c_cflag & CNO_RTSDTR) == 0) + ucom_modem(tp, SER_DTR | SER_RTS, 0); ucom_ring(sc, 0); Modified: head/sys/kern/tty.c ============================================================================== --- head/sys/kern/tty.c Wed Jun 12 16:49:01 2019 (r348998) +++ head/sys/kern/tty.c Wed Jun 12 18:07:04 2019 (r348999) @@ -93,7 +93,7 @@ static const char *dev_console_filename; FLUSHO|NOKERNINFO|NOFLSH) #define TTYSUP_CFLAG (CIGNORE|CSIZE|CSTOPB|CREAD|PARENB|PARODD|\ HUPCL|CLOCAL|CCTS_OFLOW|CRTS_IFLOW|CDTR_IFLOW|\ - CDSR_OFLOW|CCAR_OFLOW) + CDSR_OFLOW|CCAR_OFLOW|CNO_RTSDTR) #define TTY_CALLOUT(tp,d) (dev2unit(d) & TTYUNIT_CALLOUT) @@ -332,7 +332,8 @@ ttydev_open(struct cdev *dev, int oflags, int devtype if (TTY_CALLOUT(tp, dev) || dev == dev_console) tp->t_termios.c_cflag |= CLOCAL; - ttydevsw_modem(tp, SER_DTR|SER_RTS, 0); + if ((tp->t_termios.c_cflag & CNO_RTSDTR) == 0) + ttydevsw_modem(tp, SER_DTR|SER_RTS, 0); error = ttydevsw_open(tp); if (error != 0) Modified: head/sys/sys/_termios.h ============================================================================== --- head/sys/sys/_termios.h Wed Jun 12 16:49:01 2019 (r348998) +++ head/sys/sys/_termios.h Wed Jun 12 18:07:04 2019 (r348999) @@ -143,6 +143,7 @@ #define CDTR_IFLOW 0x00040000 /* DTR flow control of input */ #define CDSR_OFLOW 0x00080000 /* DSR flow control of output */ #define CCAR_OFLOW 0x00100000 /* DCD flow control of output */ +#define CNO_RTSDTR 0x00200000 /* Do not assert RTS or DTR automatically */ #endif _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
