[PATCH 6/8] serial: 8250_dwlib: remove redundant sanity check for RS485 flags

Lino Sanfilippo LinoSanfilippo at gmx.de
Wed Jun 22 08:46:57 PDT 2022


From: Lino Sanfilippo <l.sanfilippo at kunbus.com>

Before the drivers rs485_config() function is called the serial core
already ensures that only one of both options RTS on send or RTS after send
is set. So remove the concerning sanity check in the driver function to
avoid redundancy.

Signed-off-by: Lino Sanfilippo <l.sanfilippo at kunbus.com>
---
 drivers/tty/serial/8250/8250_dwlib.c | 10 ++--------
 1 file changed, 2 insertions(+), 8 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_dwlib.c b/drivers/tty/serial/8250/8250_dwlib.c
index c83e7eaf3877..bed2bd6b7a01 100644
--- a/drivers/tty/serial/8250/8250_dwlib.c
+++ b/drivers/tty/serial/8250/8250_dwlib.c
@@ -95,16 +95,10 @@ static int dw8250_rs485_config(struct uart_port *p, struct serial_rs485 *rs485)
 	if (rs485->flags & SER_RS485_ENABLED) {
 		tcr |= DW_UART_TCR_RS485_EN;
 
-		if (rs485->flags & SER_RS485_RX_DURING_TX) {
+		if (rs485->flags & SER_RS485_RX_DURING_TX)
 			tcr |= DW_UART_TCR_XFER_MODE_DE_DURING_RE;
-		} else {
-			/* HW does not support same DE level for tx and rx */
-			if (!(rs485->flags & SER_RS485_RTS_ON_SEND) ==
-			    !(rs485->flags & SER_RS485_RTS_AFTER_SEND))
-				return -EINVAL;
-
+		else
 			tcr |= DW_UART_TCR_XFER_MODE_DE_OR_RE;
-		}
 		dw8250_writel_ext(p, DW_UART_DE_EN, 1);
 		dw8250_writel_ext(p, DW_UART_RE_EN, 1);
 	} else {
-- 
2.36.1



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