From 03f32d7cb51b62f6cc7fd884d6978fe1a6ad3f8d Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Mon, 18 Jan 2021 12:13:28 +0100 Subject: [PATCH] USB: serial: cp210x: update control-characters on every change Update the XON/XOFF control characters also when no other flow-control flag has changed and software flow control is enabled. Reviewed-by: Greg Kroah-Hartman Signed-off-by: Johan Hovold --- drivers/usb/serial/cp210x.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c index ee0139eb6636..4f90573c0d2b 100644 --- a/drivers/usb/serial/cp210x.c +++ b/drivers/usb/serial/cp210x.c @@ -1113,11 +1113,13 @@ static int cp210x_set_chars(struct usb_serial_port *port, static bool cp210x_termios_change(const struct ktermios *a, const struct ktermios *b) { - bool iflag_change; + bool iflag_change, cc_change; iflag_change = ((a->c_iflag ^ b->c_iflag) & (INPCK | IXON | IXOFF)); + cc_change = a->c_cc[VSTART] != b->c_cc[VSTART] || + a->c_cc[VSTOP] != b->c_cc[VSTOP]; - return tty_termios_hw_change(a, b) || iflag_change; + return tty_termios_hw_change(a, b) || iflag_change || cc_change; } static void cp210x_set_flow_control(struct tty_struct *tty, @@ -1132,7 +1134,9 @@ static void cp210x_set_flow_control(struct tty_struct *tty, if (old_termios && C_CRTSCTS(tty) == (old_termios->c_cflag & CRTSCTS) && I_IXON(tty) == (old_termios->c_iflag & IXON) && - I_IXOFF(tty) == (old_termios->c_iflag & IXOFF)) { + I_IXOFF(tty) == (old_termios->c_iflag & IXOFF) && + START_CHAR(tty) == old_termios->c_cc[VSTART] && + STOP_CHAR(tty) == old_termios->c_cc[VSTOP]) { return; } -- 2.25.1