From 68f22c0c99d9c3534b88d1cd1215753a7a3655aa Mon Sep 17 00:00:00 2001 From: Serge Semin Date: Tue, 14 May 2019 13:14:13 +0300 Subject: [PATCH] tty: max310x: Add rx-during-tx rs485 flag support The driver currently sets the echo suppression bit by default when rs485 is enabled. Naturally it disables any data retrieval in rs485 mode while RTSn is pushed up. The receiver gate (RX_) can be enabled just by clearing (or not setting) the EchoSuprs bit of mode2 register. So by setting or clearing the bit we implement the SER_RS485_RX_DURING_TX rs485 flag support. Signed-off-by: Serge Semin Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/max310x.c | 29 ++++++++++++++--------------- 1 file changed, 14 insertions(+), 15 deletions(-) diff --git a/drivers/tty/serial/max310x.c b/drivers/tty/serial/max310x.c index ca044f96c5cc..2255300404bd 100644 --- a/drivers/tty/serial/max310x.c +++ b/drivers/tty/serial/max310x.c @@ -975,25 +975,23 @@ static void max310x_set_termios(struct uart_port *port, static void max310x_rs_proc(struct work_struct *ws) { struct max310x_one *one = container_of(ws, struct max310x_one, rs_work); - unsigned int val; + unsigned int delay, mode1 = 0, mode2 = 0; - val = (one->port.rs485.delay_rts_before_send << 4) | + delay = (one->port.rs485.delay_rts_before_send << 4) | one->port.rs485.delay_rts_after_send; - max310x_port_write(&one->port, MAX310X_HDPIXDELAY_REG, val); + max310x_port_write(&one->port, MAX310X_HDPIXDELAY_REG, delay); if (one->port.rs485.flags & SER_RS485_ENABLED) { - max310x_port_update(&one->port, MAX310X_MODE1_REG, - MAX310X_MODE1_TRNSCVCTRL_BIT, - MAX310X_MODE1_TRNSCVCTRL_BIT); - max310x_port_update(&one->port, MAX310X_MODE2_REG, - MAX310X_MODE2_ECHOSUPR_BIT, - MAX310X_MODE2_ECHOSUPR_BIT); - } else { - max310x_port_update(&one->port, MAX310X_MODE1_REG, - MAX310X_MODE1_TRNSCVCTRL_BIT, 0); - max310x_port_update(&one->port, MAX310X_MODE2_REG, - MAX310X_MODE2_ECHOSUPR_BIT, 0); + mode1 = MAX310X_MODE1_TRNSCVCTRL_BIT; + + if (!(one->port.rs485.flags & SER_RS485_RX_DURING_TX)) + mode2 = MAX310X_MODE2_ECHOSUPR_BIT; } + + max310x_port_update(&one->port, MAX310X_MODE1_REG, + MAX310X_MODE1_TRNSCVCTRL_BIT, mode1); + max310x_port_update(&one->port, MAX310X_MODE2_REG, + MAX310X_MODE2_ECHOSUPR_BIT, mode2); } static int max310x_rs485_config(struct uart_port *port, @@ -1005,7 +1003,8 @@ static int max310x_rs485_config(struct uart_port *port, (rs485->delay_rts_after_send > 0x0f)) return -ERANGE; - rs485->flags &= SER_RS485_RTS_ON_SEND | SER_RS485_ENABLED; + rs485->flags &= SER_RS485_RTS_ON_SEND | SER_RS485_RX_DURING_TX | + SER_RS485_ENABLED; memset(rs485->padding, 0, sizeof(rs485->padding)); port->rs485 = *rs485; -- 2.11.0