On Fri, Apr 15, 2016 at 11:14:11PM +0200, Grigori Goronzy wrote: No commit message? > v2: use correct flag variable. > v3: fix compilation > > Signed-off-by: Grigori Goronzy <greg@xxxxxxxxxxxx> > --- > drivers/usb/serial/ch341.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/drivers/usb/serial/ch341.c b/drivers/usb/serial/ch341.c > index e475677..7ca21a1 100644 > --- a/drivers/usb/serial/ch341.c > +++ b/drivers/usb/serial/ch341.c > @@ -68,6 +68,7 @@ > #define CH341_REQ_READ_REG 0x95 > #define CH341_REG_BREAK1 0x05 > #define CH341_REG_LCR 0x18 > +#define CH341_REG_RTSCTS 0x27 > #define CH341_NBREAK_BITS_REG1 0x01 > > #define CH341_LCR_ENABLE_RX 0x80 > @@ -399,6 +400,16 @@ static void ch341_set_termios(struct tty_struct *tty, > > ch341_set_handshake(port->serial->dev, priv->line_control); > > + if (C_CRTSCTS(tty)) { > + r = ch341_control_out(port->serial->dev, CH341_REQ_WRITE_REG, > + CH341_REG_RTSCTS | ((uint16_t)CH341_REG_RTSCTS << 8), (u16) > + 0x0101); You should also coordinate this with B0 handling (e.g. disable hard-flow control and make sure that RTS is deasserted on ->B0 transitions). > + if (r < 0) { > + dev_err(&port->dev, "%s - USB control write error (%d)\n", > + __func__, r); Please spell out what went wrong "failed to enable flow control: %d\n" > + tty->termios.c_cflag &= ~CRTSCTS; > + } > + } What about disabling flow control? > } > > static void ch341_break_ctl(struct tty_struct *tty, int break_state) Thanks, Johan -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html