[PATCH 8/9] serial: fsl_lpuart: remove redundant code in rs485_config functions

Lino Sanfilippo LinoSanfilippo at gmx.de
Sun Feb 13 14:27:36 PST 2022


When RS485 is configured by userspace the serial core already checks for
valid RTS settings and assigns the configuration to the uart port. So
remove both tasks from the code of the lpuart_config_rs485 and the
lpuart32_config_rs485 function to avoid redundancy.

Signed-off-by: Lino Sanfilippo <LinoSanfilippo at gmx.de>
---
 drivers/tty/serial/fsl_lpuart.c | 32 --------------------------------
 1 file changed, 32 deletions(-)

diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index 7d90c5a530ee..a201be44d68a 100644
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -1377,19 +1377,6 @@ static int lpuart_config_rs485(struct uart_port *port,
 		/* Enable auto RS-485 RTS mode */
 		modem |= UARTMODEM_TXRTSE;
 
-		/*
-		 * RTS needs to be logic HIGH either during transfer _or_ after
-		 * transfer, other variants are not supported by the hardware.
-		 */
-
-		if (!(rs485->flags & (SER_RS485_RTS_ON_SEND |
-				SER_RS485_RTS_AFTER_SEND)))
-			rs485->flags |= SER_RS485_RTS_ON_SEND;
-
-		if (rs485->flags & SER_RS485_RTS_ON_SEND &&
-				rs485->flags & SER_RS485_RTS_AFTER_SEND)
-			rs485->flags &= ~SER_RS485_RTS_AFTER_SEND;
-
 		/*
 		 * The hardware defaults to RTS logic HIGH while transfer.
 		 * Switch polarity in case RTS shall be logic HIGH
@@ -1402,9 +1389,6 @@ static int lpuart_config_rs485(struct uart_port *port,
 			modem |= UARTMODEM_TXRTSPOL;
 	}
 
-	/* Store the new configuration */
-	sport->port.rs485 = *rs485;
-
 	writeb(modem, sport->port.membase + UARTMODEM);
 	return 0;
 }
@@ -1428,19 +1412,6 @@ static int lpuart32_config_rs485(struct uart_port *port,
 		/* Enable auto RS-485 RTS mode */
 		modem |= UARTMODEM_TXRTSE;
 
-		/*
-		 * RTS needs to be logic HIGH either during transfer _or_ after
-		 * transfer, other variants are not supported by the hardware.
-		 */
-
-		if (!(rs485->flags & (SER_RS485_RTS_ON_SEND |
-				SER_RS485_RTS_AFTER_SEND)))
-			rs485->flags |= SER_RS485_RTS_ON_SEND;
-
-		if (rs485->flags & SER_RS485_RTS_ON_SEND &&
-				rs485->flags & SER_RS485_RTS_AFTER_SEND)
-			rs485->flags &= ~SER_RS485_RTS_AFTER_SEND;
-
 		/*
 		 * The hardware defaults to RTS logic HIGH while transfer.
 		 * Switch polarity in case RTS shall be logic HIGH
@@ -1453,9 +1424,6 @@ static int lpuart32_config_rs485(struct uart_port *port,
 			modem |= UARTMODEM_TXRTSPOL;
 	}
 
-	/* Store the new configuration */
-	sport->port.rs485 = *rs485;
-
 	lpuart32_write(&sport->port, modem, UARTMODIR);
 	return 0;
 }
-- 
2.34.1



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