diff options
| author | Nicolas Ferre <nicolas.ferre@atmel.com> | 2015-05-11 11:00:31 (GMT) |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-05-24 19:49:16 (GMT) |
| commit | 8687634b7908c42eb700e0469e110e02833611d1 (patch) | |
| tree | 1ec37190c252b116b636f2aee31f2843c2979279 /drivers/tty | |
| parent | fa8cd0f61fe17a8b202a23b68b2d0393c872372b (diff) | |
| download | linux-8687634b7908c42eb700e0469e110e02833611d1.tar.xz | |
tty/serial: at91: RS485 mode: 0 is valid for delay_rts_after_send
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@wapice.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: stable@vger.kernel.org # 3.2+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/serial/atmel_serial.c | 9 |
1 files changed, 3 insertions, 6 deletions
diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c index b1fcddd..2a8f5281 100644 --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -316,8 +316,7 @@ static int atmel_config_rs485(struct uart_port *port, 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"); @@ -355,8 +354,7 @@ static void atmel_set_mctrl(struct uart_port *port, u_int mctrl) /* override mode to RS485 if needed, otherwise keep the current mode */ if (port->rs485.flags & SER_RS485_ENABLED) { - if ((port->rs485.delay_rts_after_send) > 0) - UART_PUT_TTGR(port, port->rs485.delay_rts_after_send); + UART_PUT_TTGR(port, port->rs485.delay_rts_after_send); mode &= ~ATMEL_US_USMODE; mode |= ATMEL_US_USMODE_RS485; } @@ -2062,8 +2060,7 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios, /* mode */ if (port->rs485.flags & SER_RS485_ENABLED) { - if ((port->rs485.delay_rts_after_send) > 0) - UART_PUT_TTGR(port, port->rs485.delay_rts_after_send); + UART_PUT_TTGR(port, port->rs485.delay_rts_after_send); mode |= ATMEL_US_USMODE_RS485; } else if (termios->c_cflag & CRTSCTS) { /* RS232 with hardware handshake (RTS/CTS) */ |