设备树 如下
&uart4 {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_uart4>;
fsl,uart-has-rtscts;
status = "okay";
};
pinctrl_uart4: uart4grp {
fsl,pins = <
MX6UL_PAD_LCD_CLK__UART4_DCE_TX 0x1b0b1
MX6UL_PAD_LCD_ENABLE__UART4_DCE_RX 0x1b0b1
MX6UL_PAD_ENET1_RX_DATA0__UART4_DCE_RTS 0x79
MX6UL_PAD_ENET1_RX_DATA1__UART4_DCE_CTS 0x79
/*MX6UL_PAD_UART4_TX_DATA__UART4_DCE_TX 0x1b0b1
MX6UL_PAD_UART4_RX_DATA__UART4_DCE_RX 0x1b0b1*/
>;
};
串口状态如下
cat /proc/tty/driver/IMX-uart
serinfo:1.0 driver revision:
0: uart:IMX mmio:0x02020000 irq:58 tx:1648 rx:277 RTS|DTR|DSR|CD
1: uart:IMX mmio:0x021E8000 irq:59 tx:0 rx:0 CTS|DSR|CD
2: uart:IMX mmio:0x021EC000 irq:60 tx:0 rx:0 DSR|CD
3: uart:IMX mmio:0x021F0000 irq:61 tx:82 rx:152 DSR|CD
4: uart:IMX mmio:0x021F4000 irq:62 tx:0 rx:0 DSR|CD |