On Thu, Aug 04, 2022 at 03:04:20PM +0800, Sherry Sun wrote: > 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. > > Signed-off-by: Sherry Sun <sherry.sun@xxxxxxx> > --- > 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 fc7d235a1e27..f0fccd2ff7ac 100644 > --- a/drivers/tty/serial/fsl_lpuart.c > +++ b/drivers/tty/serial/fsl_lpuart.c > @@ -2172,6 +2172,7 @@ 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 What commit id does this fix? Should it be backported to older stable kernels? thanks, greg k-h
