Commit ab072189 authored Aug 26, 2018 by Jan Kiszka Committed by Greg Kroah-Hartman Oct 10, 2018

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



commit e0bf2d4982fe7d9ddaf550dd023803ea286f47fc upstream.

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: 30530791 ("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>

parent cdd48f38

drivers/tty/serial/mvebu-uart.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -327,8 +327,10 @@ static void mvebu_uart_set_termios(struct uart_port *port,
		if ((termios->c_cflag & CREAD) == 0)
		port->ignore_status_mask \|= STAT_RX_RDY \| STAT_BRK_ERR;

		if (old)
		if (old) {
		tty_termios_copy_hw(termios, old);
		termios->c_cflag \|= CS8;
		}

		baud = uart_get_baud_rate(port, termios, old, 0, 460800);
		uart_update_timeout(port, termios->c_cflag, baud);