Accessing device pins from board overlay

[sir_hugo]

Hi, I'm trying to write an app to capture images from a camera and was wondering how to monitor changes on specifc defined pins in the board overlay file. For example if(!pclk-gpios){ do something}

 &i2c0 {
	compatible = "nordic,nrf-twim";
	status = "okay";
	mycamera:ov7670@21 {
		compatible = "ovti,ov7670";
		label = "ov7670";
		reg = <0x21>;
		data-gpios = <&gpio0 0 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>,
			  <&gpio0 1 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>,
			  <&gpio0 5 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>,
			  <&gpio0 6 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>,
			  <&gpio0 7 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>,
			  <&gpio0 8 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>,
			  <&gpio0 9 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>,
			  <&gpio0 10 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>;       

		reset-gpios = < &gpio0 31 (GPIO_PULL_UP | GPIO_ACTIVE_HIGH) >;

		vsync-gpios = < &gpio0 15 (GPIO_PULL_UP | GPIO_ACTIVE_LOW) >;

   		hsync-gpios = < &gpio0 14 (GPIO_PULL_UP | GPIO_ACTIVE_LOW) >;

   		pclk-gpios = < &gpio0 13 (GPIO_PULL_UP | GPIO_ACTIVE_LOW) >;

   		xclk-gpios = < &gpio0 12 (GPIO_PULL_UP | GPIO_ACTIVE_LOW) >;
	};
};

[Øivind]

Hi,

That is not possible, the devicetree is a data structure used for hardware description, you can't execute code in it. You can read about how the devicetree functions here: https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/zephyr/guides/dts/intro.html

But what are you trying to achieve? I will try to help you accomplish it another way.

[sir_hugo]

Should I be using the GPIO API to achieve this?

docs.zephyrproject.org/.../gpio.html