1 // SPDX-License-Identifier: (GPL-2.0+ OR MIT) 1 // SPDX-License-Identifier: (GPL-2.0+ OR MIT)
2 /* 2 /*
3 * Copyright 2021 Gateworks Corporation 3 * Copyright 2021 Gateworks Corporation
4 * 4 *
5 * GW73xx RS422 (RS485 full duplex): 5 * GW73xx RS422 (RS485 full duplex):
6 * - GPIO1_0 rs485_term selects on-chip termi 6 * - GPIO1_0 rs485_term selects on-chip termination
7 * - GPIO4_0 rs485_en needs to be driven high 7 * - GPIO4_0 rs485_en needs to be driven high (active)
8 * - GPIO4_2 rs485_hd needs to be driven low 8 * - GPIO4_2 rs485_hd needs to be driven low (in-active)
9 * - UART4_TX is DE for RS485 transmitter 9 * - UART4_TX is DE for RS485 transmitter
10 * - RS485_EN needs to be pulled high 10 * - RS485_EN needs to be pulled high
11 * - RS485_HALF needs to be low 11 * - RS485_HALF needs to be low
12 */ 12 */
13 13
14 #include <dt-bindings/gpio/gpio.h> 14 #include <dt-bindings/gpio/gpio.h>
15 15
16 #include "imx8mm-pinfunc.h" 16 #include "imx8mm-pinfunc.h"
17 17
18 /dts-v1/; 18 /dts-v1/;
19 /plugin/; 19 /plugin/;
20 20
21 &{/} { 21 &{/} {
22 compatible = "gw,imx8mm-gw73xx-0x"; 22 compatible = "gw,imx8mm-gw73xx-0x";
23 }; 23 };
24 24
25 &gpio4 { 25 &gpio4 {
26 rs485-en-hog { 26 rs485-en-hog {
27 gpio-hog; 27 gpio-hog;
28 gpios = <0 GPIO_ACTIVE_HIGH>; 28 gpios = <0 GPIO_ACTIVE_HIGH>;
29 output-high; 29 output-high;
30 line-name = "rs485_en"; 30 line-name = "rs485_en";
31 }; 31 };
32 32
33 rs485-hd-hog { 33 rs485-hd-hog {
34 gpio-hog; 34 gpio-hog;
35 gpios = <2 GPIO_ACTIVE_HIGH>; 35 gpios = <2 GPIO_ACTIVE_HIGH>;
36 output-low; 36 output-low;
37 line-name = "rs485_hd"; 37 line-name = "rs485_hd";
38 }; 38 };
39 }; 39 };
40 40
41 &uart2 { 41 &uart2 {
42 pinctrl-names = "default"; 42 pinctrl-names = "default";
43 pinctrl-0 = <&pinctrl_uart2>; 43 pinctrl-0 = <&pinctrl_uart2>;
44 rts-gpios = <&gpio5 29 GPIO_ACTIVE_HIG 44 rts-gpios = <&gpio5 29 GPIO_ACTIVE_HIGH>;
45 linux,rs485-enabled-at-boot-time; 45 linux,rs485-enabled-at-boot-time;
46 status = "okay"; 46 status = "okay";
47 }; 47 };
48 48
49 &uart4 { 49 &uart4 {
50 status = "disabled"; 50 status = "disabled";
51 }; 51 };
52 52
53 &iomuxc { 53 &iomuxc {
54 pinctrl_uart2: uart2grp { 54 pinctrl_uart2: uart2grp {
55 fsl,pins = < 55 fsl,pins = <
56 MX8MM_IOMUXC_UART2_RXD 56 MX8MM_IOMUXC_UART2_RXD_UART2_DCE_RX 0x140
57 MX8MM_IOMUXC_UART2_TXD 57 MX8MM_IOMUXC_UART2_TXD_UART2_DCE_TX 0x140
58 MX8MM_IOMUXC_UART4_TXD 58 MX8MM_IOMUXC_UART4_TXD_GPIO5_IO29 0x140
59 >; 59 >;
60 }; 60 };
61 }; 61 };
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