Hi All,
I am new to NXP IMX8 Processors. I am working on i.MX 8M Nano Evk, I have to enable GPIOs (any two) and simply set it to HIGH/LOW.
In the schematic if we check the header J1003 we can see the information related to pins that are physically available to use. Here I am not using UART, so the pins UART3_CTS and UART3_RTS are also named GPIO.7 & GPIO.0 respectively, I want them to use it as regular gpios.
So after searching in the internet I found out that we need to add information related to GPIOs in the device tree. Here are some of links for Ref :
https://www.emcraft.com/som/imx-8m/controlling-gpio-in-linux
https://www.digi.com/resources/documentation/digidocs/embedded/dey/2.6/cc8mnano/bsp_r_gpio_8m
https://www.variscite.com/blog/i-mx-device-tree-pinmux-settings/
https://variwiki.com/index.php?title=MX8M_GPIO#Pin_Func_files
And also if the gpios are enabled, the we can control them using the gpiochip utility.
Following are some of my doubts :
- Here https://variwiki.com/index.php?title=MX8M_GPIO#Pin_Func_files it says to set GPIO4_21
gpioset gpiochip3 21= 1
But as per schematic it is UART3_CTS (GPIO.7) & UART_3RTS(GPIO.0), How can I find which GPIOs are actually available on the header ? and what would be the correct gpiochip and its line number for the GPIOs, where can I find these details? - Is there a standard steps or procedure for enabling and using the GPIO in i.MX8 evk ?
