tty: serial: fsl_lpuart: specify transmit FIFO size

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>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index b1893f3f88f1..7ec911000ec2 100644
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -1076,6 +1076,8 @@ 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);