avr32: add hardware handshake support to atmel_serial
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@mediamatech.com>
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
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 @@
/* 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 @@
} 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;