From 2b9e6f0a400b6be1a408cd63ed09cfeb8f5dd627 Mon Sep 17 00:00:00 2001 From: Serge Semin Date: Tue, 14 May 2019 13:14:14 +0300 Subject: [PATCH] tty: max310x: Optionally enable rs485 on startup UART port might be pre-configured with rs485 enabled flag at the time of the port starting up process. In this case we need to have the hardware rs485-related registers initialized in accordance with the rs485 flags and settings provided by the configs descriptor. Signed-off-by: Serge Semin Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/max310x.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/drivers/tty/serial/max310x.c b/drivers/tty/serial/max310x.c index 2255300404bd..36943f6c198c 100644 --- a/drivers/tty/serial/max310x.c +++ b/drivers/tty/serial/max310x.c @@ -1030,6 +1030,22 @@ static int max310x_startup(struct uart_port *port) max310x_port_update(port, MAX310X_MODE2_REG, MAX310X_MODE2_FIFORST_BIT, 0); + /* Configure mode1/mode2 to have rs485/rs232 enabled at startup */ + val = (clamp(port->rs485.delay_rts_before_send, 0U, 15U) << 4) | + clamp(port->rs485.delay_rts_after_send, 0U, 15U); + max310x_port_write(port, MAX310X_HDPIXDELAY_REG, val); + + if (port->rs485.flags & SER_RS485_ENABLED) { + max310x_port_update(port, MAX310X_MODE1_REG, + MAX310X_MODE1_TRNSCVCTRL_BIT, + MAX310X_MODE1_TRNSCVCTRL_BIT); + + if (!(port->rs485.flags & SER_RS485_RX_DURING_TX)) + max310x_port_update(port, MAX310X_MODE2_REG, + MAX310X_MODE2_ECHOSUPR_BIT, + MAX310X_MODE2_ECHOSUPR_BIT); + } + /* Configure flow control levels */ /* Flow control halt level 96, resume level 48 */ max310x_port_write(port, MAX310X_FLOWLVL_REG, -- 2.45.2