When the user initializes the uart port, and waits for the transmit engine to complete in lpuart32_set_termios(), if the UART TX fifo has dirty data and the UARTMODIR enable the flow control, the TX fifo may never be empty. So here we should disable the flow control first to make sure the transmit engin can complete. Fixes: 380c966c093e ("tty: serial: fsl_lpuart: add 32-bit register interface support") Signed-off-by: Sherry Sun <sherry.sun@xxxxxxx> --- Changes in V3: 1. Add the Fixes tag. Changes in V2: 1. Rephrase the commit log as suggested by Jiri. --- drivers/tty/serial/fsl_lpuart.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c index f6c33cd228c8..fb2ad5d0d368 100644 --- a/drivers/tty/serial/fsl_lpuart.c +++ b/drivers/tty/serial/fsl_lpuart.c @@ -2191,6 +2191,7 @@ lpuart32_set_termios(struct uart_port *port, struct ktermios *termios, uart_update_timeout(port, termios->c_cflag, baud); /* wait transmit engin complete */ + lpuart32_write(&sport->port, 0, UARTMODIR); lpuart32_wait_bit_set(&sport->port, UARTSTAT, UARTSTAT_TC); /* disable transmit and receive */ -- 2.17.1