RE: Zephyr GPIO initialization before HW drivers

Håkon Alseth — Wed, 18 Aug 2021 06:49:53 GMT

Glad to hear that, Morten!

Let me know if you run into any issues.

Cheers,

Håkon

RE: Zephyr GPIO initialization before HW drivers

Morten Sabinsky — Wed, 18 Aug 2021 06:29:36 GMT

Thanks this is what i needed

Morten

RE: Zephyr GPIO initialization before HW drivers

Håkon Alseth — Tue, 17 Aug 2021 13:47:58 GMT

Hi,

GPIOs that needs to be set prior to initialization usually gets placed in a PRE_KERNEL system init, like done here for the nrf9160dk_nrf52840 board.c file:

https://github.com/nrfconnect/sdk-zephyr/blob/master/boards/arm/nrf9160dk_nrf52840/board.c#L217-L240

The problem with setting a gpio before the "zephyr gpio" driver is initialized is that you cannot use the zephyr driver instance to set it, so you need to use the nrf_gpio.h (or other bare metal implementations) to configure/set. It isn't clear if this is a restriction in your case, or if you want to set these before communicating with an external IC or similar.

If you require setting this with a higher priority than another module (ie. in a situation where zephyr's gpio is already inited), you can look at the sys_init() macro for the module in question, and setup one that happens before it: https://docs.zephyrproject.org/latest/reference/drivers/index.html#c.SYS_INIT

Kind regards,

Håkon