Re: [PATCH] serial: max310x: Properly set flags in AutoCTS mode

From: Greg Kroah-Hartman
Date: Wed Sep 04 2019 - 03:30:15 EST


On Fri, Aug 30, 2019 at 09:58:34AM +0000, Christoph Vogtländer wrote:
> Commit 391f93f2ec9f ("serial: core: Rework hw-assisted flow control
> support") has changed the way the AutoCTS mode is handled.
>
> According to that change, serial drivers which enable H/W AutoCTS mode must
> set UPSTAT_AUTORTS, UPSTAT_AUTOCTS and UPSTAT_AUTOXOFF to prevent the
> serial core from inadvertently disabling RX or TX. This patch adds proper
> handling of UPSTAT_AUTORTS, UPSTAT_AUTOCTS and UPSTAT_AUTOXOFF flags.
>
> Signed-off-by: Christoph Vogtländer <c.vogtlaender@xxxxxxxxxxxxxxxxxxxxxxxxx>
> ---
> drivers/tty/serial/max310x.c | 12 ++++++++++--
> 1 file changed, 10 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/tty/serial/max310x.c b/drivers/tty/serial/max310x.c
> index 0e24235..fb5a7e0 100644
> --- a/drivers/tty/serial/max310x.c
> +++ b/drivers/tty/serial/max310x.c
> @@ -859,15 +859,23 @@ static void max310x_set_termios(struct uart_port *port,
> /* Configure flow control */
> max310x_port_write(port, MAX310X_XON1_REG, termios->c_cc[VSTART]);
> max310x_port_write(port, MAX310X_XOFF1_REG, termios->c_cc[VSTOP]);
> -if (termios->c_cflag & CRTSCTS)
> +
> +port->status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS | UPSTAT_AUTOXOFF);
> +
> +if (termios->c_cflag & CRTSCTS) {
> +/* Enable AUTORTS and AUTOCTS */
> +port->status |= UPSTAT_AUTOCTS | UPSTAT_AUTORTS;
> flow |= MAX310X_FLOWCTRL_AUTOCTS_BIT |
> MAX310X_FLOWCTRL_AUTORTS_BIT;
> +}
> if (termios->c_iflag & IXON)
> flow |= MAX310X_FLOWCTRL_SWFLOW3_BIT |
> MAX310X_FLOWCTRL_SWFLOWEN_BIT;
> -if (termios->c_iflag & IXOFF)
> +if (termios->c_iflag & IXOFF) {
> +port->status |= UPSTAT_AUTOXOFF;
> flow |= MAX310X_FLOWCTRL_SWFLOW1_BIT |
> MAX310X_FLOWCTRL_SWFLOWEN_BIT;
> +}
> max310x_port_write(port, MAX310X_FLOWCTRL_REG, flow);
>
> /* Get baud rate generator configuration */
> --
> 2.7.4

Your email client ate all of the leading spaces and tabs and spit out a
patch that is impossible to apply :(

Please fix that up and resend.

thanks,

greg k-h