imx6q run kk4.4.2_1.0.0-ga on my custom board.
set /dev/ttymxc2 to rs485 mode from user space with the attached file, but the CTS_B pin still be high, what's the reason, please give a hand, thanks.
when i run set_rs485 in command line(cross-compiled from attached file set_rs485.c), use oscilloscope detect a fall edge on UART3_CTS_B, but at once the pin back to high again, what's others operates UCR2_CTS else?
static int imx_rs485_config(struct uart_port *port,
struct serial_rs485 *rs485conf)
{
struct imx_port *sport = (struct imx_port *)port;
/* unimplemented */
rs485conf->delay_rts_before_send = 0;
rs485conf->delay_rts_after_send = 0;
rs485conf->flags |= SER_RS485_RX_DURING_TX;
/* RTS is required to control the transmitter */
if (!sport->have_rtscts)
rs485conf->flags &= ~SER_RS485_ENABLED;
if (rs485conf->flags & SER_RS485_ENABLED) {
unsigned long temp;
/* disable transmitter */
temp = readl(sport->port.membase + UCR2);
temp &= ~UCR2_CTSC;
if (rs485conf->flags & SER_RS485_RTS_AFTER_SEND)
temp &= ~UCR2_CTS;
else
temp |= UCR2_CTS;
writel(temp, sport->port.membase + UCR2);
}
port->rs485 = *rs485conf;
return 0;
}
