tty: serial: fsl_lpuart: specify transmit FIFO size

commit 4e8f245937091b2c9eebf3d4909c9ceda4f0a78e upstream.

Specify transmit FIFO size which might be different depending on
LPUART instance. This makes sure uart_wait_until_sent in serial
core getting called, which in turn waits and checks if the FIFO
is really empty on shutdown by using the tx_empty callback.
Without the call of this callback, the last several characters
might not yet be transmitted when closing the serial port. This
can be reproduced by simply using echo and redirect the output to
a ttyLP device.

Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index e95c4971327bff183f5ea191adf18b92f7de72b8..1657514f56d260fac207fb628a025fd19db67e39 100644 (file)
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -1095,6 +1095,8 @@ static int lpuart_startup(struct uart_port *port)
        sport->txfifo_size = 0x1 << (((temp >> UARTPFIFO_TXSIZE_OFF) &
                UARTPFIFO_FIFOSIZE_MASK) + 1);
 
+       sport->port.fifosize = sport->txfifo_size;
+
        sport->rxfifo_size = 0x1 << (((temp >> UARTPFIFO_RXSIZE_OFF) &
                UARTPFIFO_FIFOSIZE_MASK) + 1);