RE: Device Tree Configuration Generic GPIO Inputs & Outputs

CCL-KH — Mon, 21 Aug 2023 09:19:59 GMT

Thank you

I am using gpio_pin_configure() to set all the properties of the GPIO (e.g. direction, polarity, biasing) pragmatically during app code initialisation. I believe this means the GPIO will behave as default configuration during the kernel pre init (etc) stages. This approach is simpler and avoids DTS for non-module (SPI, I2C etc) related GPIOs

RE: Device Tree Configuration Generic GPIO Inputs & Outputs

Vidar Berg — Mon, 24 Jul 2023 14:56:05 GMT

Hello,

Yes, the Device Tree is supposed to describe the hardware configuration of your board, such as whether the LED/button is active low or not. This allows you to use the GPIO *_dt functions in your program without worrying about the polarity for different boards. However, the code is still responsible for configuring the direction of the GPIO, but I would have to ask the developers about the reasoning behind this. The GPIO flags, which can be defined in the gpio handle, can be found here:

https://github.com/nrfconnect/sdk-zephyr/blob/434be7b575ce338645801140fbd2e64738f8994e/include/zephyr/dt-bindings/gpio/gpio.h

Best regards,

Vidar