diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index bba54ad0d434..94e0781e00e8 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -801,6 +801,21 @@ static irqreturn_t __imx_uart_rtsint(int irq, void *dev_id) imx_uart_writel(sport, USR1_RTSD, USR1); usr1 = imx_uart_readl(sport, USR1) & USR1_RTSS; + /* + * Update sport->old_status here, so any follow-up calls to + * imx_uart_mctrl_check() will be able to recognize that RTS + * state changed since last imx_uart_mctrl_check() call. + * + * In case RTS has been detected as asserted here and later on + * deasserted by the time imx_uart_mctrl_check() was called, + * imx_uart_mctrl_check() can detect the RTS state change and + * trigger uart_handle_cts_change() to unblock the port for + * further TX transfers. + */ + if (usr1 & USR1_RTSS) + sport->old_status |= TIOCM_CTS; + else + sport->old_status &= ~TIOCM_CTS; uart_handle_cts_change(&sport->port, usr1); wake_up_interruptible(&sport->port.state->port.delta_msr_wait);