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External Buildroot tree for STMicroelectronics boards configurations
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Enable GPIO on STM32MP157F-DK2 #34

Closed AaronMill93 closed 1 year ago

AaronMill93 commented 1 year ago

Hi,

I'm following the STM32CubeMX devicetree doc in an attempt to enable SPI for the STM32MP157F-DK2. I was able to figure out the SPI pins and added the necessary code as per tutorial. I'm just wondering if there's anything extra needed to enable a GPIO pin for SS (e.g. PA8)? I did a diff of the generated code from CubeMX with and without activating PA8 but there seems to be no changes. Any help is appreciated. I also spent some time looking through other issues and attempting to figure it out but no luck so far.

Aaron

kmaincent commented 1 year ago

Hello, In the devicetree you will need to specify the gpio in the spi-bus node with the cs-gpio parameter: https://elixir.bootlin.com/linux/v5.15.111/source/Documentation/devicetree/bindings/spi/spi-controller.yaml#L28 And configure the GPIO pin for SS in the pinctrl with ANALOG function, here are few examples: https://elixir.bootlin.com/linux/v5.15.111/source/arch/arm/boot/dts/stm32mp15-pinctrl.dtsi

AaronMill93 commented 1 year ago

I figured this out myself, but thank you for the reply. From my experience, there is currently no way to use SPI functionality on the current branch. /dev/spi0.0 will only be populated after the instructions from ST are followed properly and buildroot from branch st/2021.02 is used.

I would like to make this visible to save other users some time.

kmaincent commented 1 year ago

Done dc13f5a