atmel_serial: fix RTS high after initialization in RS485 mode

Claudio Scordino claudio at evidence.eu.com
Sun Oct 24 06:48:29 EDT 2010


Hi Nicolas,

	when working in RS485 mode, the atmel_serial driver keeps RTS
high after the initialization of the serial port. It goes low only after
the first character has been sent. 

This patch fixes this behavior. It has been already tested by Arkadiusz (CC:-ed).

Best regards,

	Claudio


atmel_serial: RTS line low after initialization of the serial port

Signed-off-by: Claudio Scordino <claudio at evidence.eu.com>
Signed-off-by: Arkadiusz Bubala <arkadiusz.bubala at gmail.com>
---
 drivers/serial/atmel_serial.c |    9 +++++++++
 1 files changed, 9 insertions(+), 0 deletions(-)

diff --git a/drivers/serial/atmel_serial.c b/drivers/serial/atmel_serial.c
index 3892666..85aa66f 100644
--- a/drivers/serial/atmel_serial.c
+++ b/drivers/serial/atmel_serial.c
@@ -1732,6 +1732,15 @@ static int __devinit atmel_serial_probe(struct platform_device *pdev)
 	device_init_wakeup(&pdev->dev, 1);
 	platform_set_drvdata(pdev, port);
 
+	if (port->rs485.flags & SER_RS485_ENABLED) {
+		unsigned int control = 0;
+		unsigned int mode = 0;
+		control |= ATMEL_US_RTSEN;
+		mode |= ATMEL_US_USMODE_NORMAL;
+		UART_PUT_MR(&port->uart, mode);
+		UART_PUT_CR(&port->uart, control);
+	}
+
 	return 0;
 
 err_add_port:
-- 
1.6.0.4




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