[PATCH 2/2] avr32: add hardware handshake support to atmel_serial

From: Haavard Skinnemoen
Date: Wed Apr 01 2009 - 04:54:35 EST


From: Peter Ma <pma@xxxxxxxxxxxxxxx>

Adds Hardware Handshake (aka RTS/CTS flow-control) support to
atmel_serial driver, as a termios flag.

For this to actually work, the platform code needs to configure the RTS
and CTS pins for use by the USART. This has been done for AVR32 as a
separate patch.

Signed-off-by: Peter Ma <pma@xxxxxxxxxxxxxxx>
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@xxxxxxxxx>
---
drivers/serial/atmel_serial.c | 9 ++++++++-
1 files changed, 8 insertions(+), 1 deletions(-)

diff --git a/drivers/serial/atmel_serial.c b/drivers/serial/atmel_serial.c
index 8f58f7f..b3497d7 100644
--- a/drivers/serial/atmel_serial.c
+++ b/drivers/serial/atmel_serial.c
@@ -1020,7 +1020,8 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios,

/* Get current mode register */
mode = UART_GET_MR(port) & ~(ATMEL_US_USCLKS | ATMEL_US_CHRL
- | ATMEL_US_NBSTOP | ATMEL_US_PAR);
+ | ATMEL_US_NBSTOP | ATMEL_US_PAR
+ | ATMEL_US_USMODE);

baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
quot = uart_get_divisor(port, baud);
@@ -1065,6 +1066,12 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios,
} else
mode |= ATMEL_US_PAR_NONE;

+ /* hardware handshake (RTS/CTS) */
+ if (termios->c_cflag & CRTSCTS)
+ mode |= ATMEL_US_USMODE_HWHS;
+ else
+ mode |= ATMEL_US_USMODE_NORMAL;
+
spin_lock_irqsave(&port->lock, flags);

port->read_status_mask = ATMEL_US_OVRE;
--
1.6.0.4

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