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| author | Nicolas Ferre <nicolas.ferre@atmel.com> | 2015-05-11 13:00:31 +0200 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2015-08-12 16:33:12 +0200 |
| commit | f312564391d123f530d30ea4d1d9431dd7f5a6dc (patch) | |
| tree | 24ee7e726e40f86a6cf1ba5f70231b157f509908 /drivers/tty | |
| parent | 7acdcce017318585ddb3eacd1d04610b62f181a5 (diff) | |
| download | kernel_samsung_smdk4412-f312564391d123f530d30ea4d1d9431dd7f5a6dc.zip kernel_samsung_smdk4412-f312564391d123f530d30ea4d1d9431dd7f5a6dc.tar.gz kernel_samsung_smdk4412-f312564391d123f530d30ea4d1d9431dd7f5a6dc.tar.bz2 | |
tty/serial: at91: RS485 mode: 0 is valid for delay_rts_after_send
commit 8687634b7908c42eb700e0469e110e02833611d1 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/serial/atmel_serial.c | 11 |
1 files changed, 3 insertions, 8 deletions
diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c index 99fcb8c..9645186 100644 --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -229,8 +229,7 @@ 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"); @@ -305,9 +304,7 @@ static void atmel_set_mctrl(struct uart_port *port, u_int mctrl) if (atmel_port->rs485.flags & SER_RS485_ENABLED) { dev_dbg(port->dev, "Setting UART to RS485\n"); - 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; } else { dev_dbg(port->dev, "Setting UART to RS232\n"); @@ -1229,9 +1226,7 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios, if (atmel_port->rs485.flags & SER_RS485_ENABLED) { dev_dbg(port->dev, "Setting UART to RS485\n"); - 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; } else { dev_dbg(port->dev, "Setting UART to RS232\n"); |