1// SPDX-License-Identifier: (GPL-2.0+ OR MIT) 2/* 3 * Copyright 2022 Gateworks Corporation 4 * 5 * GW72xx RS232 with RTS/CTS hardware flow control: 6 * - GPIO4_0 rs485_en needs to be driven low (in-active) 7 * - UART4_TX becomes RTS 8 * - UART4_RX becomes CTS 9 */ 10 11#include <dt-bindings/gpio/gpio.h> 12 13#include "imx8mm-pinfunc.h" 14 15/dts-v1/; 16/plugin/; 17 18&{/} { 19 compatible = "gw,imx8mm-gw72xx-0x"; 20}; 21 22&gpio4 { 23 rs485_en { 24 gpio-hog; 25 gpios = <0 GPIO_ACTIVE_HIGH>; 26 output-low; 27 line-name = "rs485_en"; 28 }; 29}; 30 31&uart2 { 32 pinctrl-names = "default"; 33 pinctrl-0 = <&pinctrl_uart2>; 34 rts-gpios = <&gpio5 29 GPIO_ACTIVE_LOW>; 35 cts-gpios = <&gpio5 28 GPIO_ACTIVE_LOW>; 36 uart-has-rtscts; 37 status = "okay"; 38}; 39 40&uart4 { 41 status = "disabled"; 42}; 43 44&iomuxc { 45 pinctrl_uart2: uart2grp { 46 fsl,pins = < 47 MX8MM_IOMUXC_UART2_RXD_UART2_DCE_RX 0x140 48 MX8MM_IOMUXC_UART2_TXD_UART2_DCE_TX 0x140 49 MX8MM_IOMUXC_UART4_TXD_GPIO5_IO29 0x140 50 MX8MM_IOMUXC_UART4_RXD_GPIO5_IO28 0x140 51 >; 52 }; 53}; 54