serial: 8250_dwlib: remove redundant sanity check for RS485 flags

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.

Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Link: https://lore.kernel.org/r/20220710164442.2958979-8-LinoSanfilippo@gmx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/8250/8250_dwlib.c b/drivers/tty/serial/8250/8250_dwlib.c
index 2c3b1468bd8878503d2a7f2d7a1f9a259b60f676..dbe4d44f60d4ce6d72e23d26dbd419b526dd947e 100644 (file)
--- 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 {