serial: mvebu-uart: Fix reporting of effective CSIZE to userspace

Apparently, this driver (or the hardware) does not support character
length settings. It's apparently running in 8-bit mode, but it makes
userspace believe it's in 5-bit mode. That makes tcsetattr with CS8
incorrectly fail, breaking e.g. getty from busybox, thus the login shell
on ttyMVx.

Fix by hard-wiring CS8 into c_cflag.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Fixes: 30530791a7a0 ("serial: mvebu-uart: initial support for Armada-3700 serial port")
Cc: stable <stable@vger.kernel.org> # 4.6+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/mvebu-uart.c b/drivers/tty/serial/mvebu-uart.c
index d04b5ee..170e446 100644 (file)
--- a/drivers/tty/serial/mvebu-uart.c
+++ b/drivers/tty/serial/mvebu-uart.c
@@ -511,6 +511,7 @@ static void mvebu_uart_set_termios(struct uart_port *port,
                termios->c_iflag |= old->c_iflag & ~(INPCK | IGNPAR);
                termios->c_cflag &= CREAD | CBAUD;
                termios->c_cflag |= old->c_cflag & ~(CREAD | CBAUD);
+               termios->c_cflag |= CS8;
        }
 
        spin_unlock_irqrestore(&port->lock, flags);