On Fri, Aug 30, 2019 at 09:58:41AM +0000, Christoph Vogtländer wrote: > As documented in the data-sheet, the transmitter must be disabled before > activating AutoCTS or auto transmitter flow control. Accordingly, the > transmitter must be enabled after AutoCTS or auto transmitter flow > control gets deactivated. > > Signed-off-by: Christoph Vogtländer <c.vogtlaender@xxxxxxxxxxxxxxxxxxxxxxxxx> > --- > drivers/tty/serial/max310x.c | 18 ++++++++++++++++++ > 1 file changed, 18 insertions(+) > > diff --git a/drivers/tty/serial/max310x.c b/drivers/tty/serial/max310x.c > index fb5a7e0e58e9..adfef6dae4a7 100644 > --- a/drivers/tty/serial/max310x.c > +++ b/drivers/tty/serial/max310x.c > @@ -860,6 +860,15 @@ static void max310x_set_termios(struct uart_port *port, > max310x_port_write(port, MAX310X_XON1_REG, termios->c_cc[VSTART]); > max310x_port_write(port, MAX310X_XOFF1_REG, termios->c_cc[VSTOP]); > > +/* Disable transmitter before enabling AutoCTS or auto transmitter > + * flow control > + */ > +if (termios->c_cflag & CRTSCTS || termios->c_iflag & IXOFF) { > +max310x_port_update(port, MAX310X_MODE1_REG, > + MAX310X_MODE1_TXDIS_BIT, > + MAX310X_MODE1_TXDIS_BIT); > +} > + > port->status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS | UPSTAT_AUTOXOFF); > > if (termios->c_cflag & CRTSCTS) { > @@ -878,6 +887,15 @@ static void max310x_set_termios(struct uart_port *port, > } > max310x_port_write(port, MAX310X_FLOWCTRL_REG, flow); > > +/* Enable transmitter after disabling AutoCTS and auto transmitter > + * flow control > + */ > +if (!(termios->c_cflag & CRTSCTS) && !(termios->c_iflag & IXOFF)) { > +max310x_port_update(port, MAX310X_MODE1_REG, > + MAX310X_MODE1_TXDIS_BIT, > + 0); > +} > + > /* Get baud rate generator configuration */ > baud = uart_get_baud_rate(port, termios, old, > port->uartclk / 16 / 0xffff, > -- > 2.22.1 > Same problem here, this is impossible to apply. greg k-h