Gpio startup sequence for imx8qm apalis module

Hello everyone,

I am using an apalis imx8qm module mounted on an Ixora board version 1.2.

right now when starting the ixora board the gpio pins (1-8) goes high for ~1.3 seconds then set to “low” as set up in pinmux.c , also the pins are connected to ground with a pull down resistor, my question is, is there any way to prevent this behavior and keep the pins grounded during startup ?

thank you

Hello @AhmedMobarez ,
You can try setting the GPIO values at boot time, as described in this thread:

Best regards,
Josep

1 Like

Hello @AhmedMobarez ,
Do you have any updates on this topic?

Best regards,
Josep

Hello @josep.tx ,

Thank you for following up, unfortunately I didn’t have time to test this issue, but I will test it early next week and let you know to close the thread, sorry for the delay.

but just to make sure, setting the pin levels in the device tree won’t conflict with controlling the pins from the firmware later?

Best,
Ahmed

Hello @AhmedMobarez ,

The title of the topic is misleading, it’s not about setting the pin levels in the device tree but setting them at boot time, in the U-Boot configuration.

Please check the proposed solution, it might solve your issue.

Best regards,
Josep