Hi,
I don't see any DTS attached, you have to change it because they are UART3 flow control.
Which are used in EVK as UART flow control signals mapped to J1003.
josephlinares_3-1699379866422.png
In dtsi, they are used as UART 3 pins.
pinctrl_uart3: uart3grp {
fsl,pins = <
MX8MM_IOMUXC_ECSPI1_SCLK_UART3_DCE_RX 0x140
MX8MM_IOMUXC_ECSPI1_MOSI_UART3_DCE_TX 0x140
MX8MM_IOMUXC_ECSPI1_SS0_UART3_DCE_RTS_B 0x140
MX8MM_IOMUXC_ECSPI1_MISO_UART3_DCE_CTS_B 0x140
>;
};
&uart3 {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_uart3>;
assigned-clocks = <&clk IMX8MM_CLK_UART3>;
assigned-clock-parents = <&clk IMX8MM_SYS_PLL1_80M>;
fsl,uart-has-rtscts;
status = "okay";
};
If you made the changes properly, you should be able to set and clear the GPIO signals with these commands:
#command to turn off the led
root@imx8mnevk:~# echo 0 >> /sys/class/leds/yellow\:status/brightness
#command to turn on the led
root@imx8mnevk:~# echo 1 >> /sys/class/leds/yellow\:status/brightness
Regards,