From 9d9398944488cd3a3e1e0912b26fbc4d5921e547 Mon Sep 17 00:00:00 2001 From: Daniel Golle Date: Mon, 4 Jun 2018 23:33:07 +0200 Subject: [PATCH] tty: serial: exar: generalize RS485 setup Move the non-board-specific part of the RS485 initialization from iot2040_rs485_config function to a new generic function used also for other boards. This allows using TIOCGRS485 and TIOCSRS485 on boards (such as mPCIe serial IO modules) which are hard-wired to RS485 or have jumpers for their configurations. Signed-off-by: Daniel Golle Reviewed-by: Jan Kiszka Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/8250_exar.c | 38 +++++++++++++++++++---------- 1 file changed, 25 insertions(+), 13 deletions(-) --- a/drivers/tty/serial/8250/8250_exar.c +++ b/drivers/tty/serial/8250/8250_exar.c @@ -283,8 +283,32 @@ static int xr17v35x_register_gpio(struct return 0; } +static int generic_rs485_config(struct uart_port *port, + struct serial_rs485 *rs485) +{ + bool is_rs485 = !!(rs485->flags & SER_RS485_ENABLED); + u8 __iomem *p = port->membase; + u8 value; + + value = readb(p + UART_EXAR_FCTR); + if (is_rs485) + value |= UART_FCTR_EXAR_485; + else + value &= ~UART_FCTR_EXAR_485; + + writeb(value, p + UART_EXAR_FCTR); + + if (is_rs485) + writeb(UART_EXAR_RS485_DLY(4), p + UART_MSR); + + port->rs485 = *rs485; + + return 0; +} + static const struct exar8250_platform exar8250_default_platform = { .register_gpio = xr17v35x_register_gpio, + .rs485_config = generic_rs485_config, }; static int iot2040_rs485_config(struct uart_port *port, @@ -317,19 +341,7 @@ static int iot2040_rs485_config(struct u value |= mode; writeb(value, p + UART_EXAR_MPIOLVL_7_0); - value = readb(p + UART_EXAR_FCTR); - if (is_rs485) - value |= UART_FCTR_EXAR_485; - else - value &= ~UART_FCTR_EXAR_485; - writeb(value, p + UART_EXAR_FCTR); - - if (is_rs485) - writeb(UART_EXAR_RS485_DLY(4), p + UART_MSR); - - port->rs485 = *rs485; - - return 0; + return generic_rs485_config(port, rs485); } static const struct property_entry iot2040_gpio_properties[] = {