Default GPIO state

[Peter VW]

Hello,

I'm currently working on a reset pin for our hardware. Currently it's connected to GPIO 53 (on J3 pin 9)

I would like this pin to be zero (instead of default HIGH). Currently i did it with a init script. But this runs after the initial value of input pullup.

Is there an easy way to make this happen? At default we would like this pin to be OUTPUT and LOW.

Thank you in advance.

[modaltb]

Hi @Peter-VW ,

Yes correct, we have that defaulted HIGH for one of our modems, that's being set in the kernel here, which is the only way I know how to set a default value....

https://gitlab.com/voxl-public/system-image-build/meta-voxl2-bsp/-/blob/master/recipes-kernel/linux-msm/files/dts/common/m0xxx-kona-pinctrl.dtsi#L125

So, I don't know if this is 'easy' but a kernel rebuild to set default state is currently needed. We've not figured out a way to do DT changes 'run time' at this point.

[Peter VW]

Thank you, then we will take a look into this.
For now, a simple RC circuit works.