[PATCH v3 7/8] serial: 8250_dwlib: remove redundant sanity check for RS485 flags

Lino Sanfilippo LinoSanfilippo at gmx.de
Sun Jul 10 08:03:21 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>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen at linux.intel.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 2c3b1468bd88..dbe4d44f60d4 100644
--- a/drivers/tty/serial/8250/8250_dwlib.c
+++ b/drivers/tty/serial/8250/8250_dwlib.c
@@ -187,16 +187,10 @@ static int dw8250_rs485_config(struct uart_port *p, struct ktermios *termios,
 	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 {
-- 
2.25.1



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