From: Nicolas Ferre <nicolas.ferre@xxxxxxxxx> This patch has been added to the 3.18 stable tree. If you have any objections, please let us know. =============== [ Upstream commit 8687634b7908c42eb700e0469e110e02833611d1 ] In RS485 mode, we may want to set the delay_rts_after_send value to 0. In the datasheet, the 0 value is said to "disable" the Transmitter Timeguard but this is exactly the expected behavior if we want no delay... Moreover, if the value was set to non-zero value by device-tree or earlier ioctl command, it was impossible to change it back to zero. Reported-by: Sami Pietikäinen <Sami.Pietikainen@xxxxxxxxxx> Signed-off-by: Nicolas Ferre <nicolas.ferre@xxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx # 3.2+ Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sasha.levin@xxxxxxxxxx> --- drivers/tty/serial/atmel_serial.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c index 11300f7..daaed7c 100644 --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -311,8 +311,7 @@ void atmel_config_rs485(struct uart_port *port, struct serial_rs485 *rs485conf) if (rs485conf->flags & SER_RS485_ENABLED) { dev_dbg(port->dev, "Setting UART to RS485\n"); atmel_port->tx_done_mask = ATMEL_US_TXEMPTY; - if ((rs485conf->delay_rts_after_send) > 0) - UART_PUT_TTGR(port, rs485conf->delay_rts_after_send); + UART_PUT_TTGR(port, rs485conf->delay_rts_after_send); mode |= ATMEL_US_USMODE_RS485; } else { dev_dbg(port->dev, "Setting UART to RS232\n"); @@ -2016,9 +2015,7 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios, mode &= ~ATMEL_US_USMODE; if (atmel_port->rs485.flags & SER_RS485_ENABLED) { - if ((atmel_port->rs485.delay_rts_after_send) > 0) - UART_PUT_TTGR(port, - atmel_port->rs485.delay_rts_after_send); + UART_PUT_TTGR(port, atmel_port->rs485.delay_rts_after_send); mode |= ATMEL_US_USMODE_RS485; } -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html