Zephyr new device binding

Question

Hello,

My development requires new device binding and I want to share the steps followed and my issue.

My device is Renesas and commuicate via I2C protocol.

Based on vendors available,I have to proceed with the following step:

create a new file renesas,mydevice.yaml
Copy it in my root path "dts\bindings\sensor"
In .dts file:

&i2c1 {
	compatible = "nordic,nrf-twim";
	status = "okay";
	sda-pin = <34>;
	scl-pin = <35>;

	mydevice@53{
		compatible = "renesas,mydevice";
		label = "MYDEVICE";
		reg = <0x53>;
	};
};

where i2c1 is the node defined in .dtsi.

Well, I can build my project and I can use my custom library to communicate with it.

My issue regarding the device that provide also an interrupt when data is ready, then how can I proceed?

Must I define the interrupt properties in my binding file? If yes, what is the best way?
Or, Can I maintain the current implementation and manage interrupt in .dts as gpio?

Thank you in advance.

Øivind · Accepted Answer

Hi,

What does your .yaml file look like? I would expect it to have a compatible field with "renesas,mydevice" and an include field with i2c-device.yaml.

If that is the case, just add a property for the interrupt gpio:

compatible: "renesas,mydevice"

include: i2c-device.yaml

properties:
    int-gpios:
      type: phandle-array
      required: true

Then you can assign a gpio pin to your mydevice node in the dts file:

&i2c1 {
	compatible = "nordic,nrf-twim";
	status = "okay";
	sda-pin = <34>;
	scl-pin = <35>;

	mydevice@53{
		compatible = "renesas,mydevice";
		label = "MYDEVICE";
		reg = <0x53>;
		int-gpios = <&gpio1 4 0>;
	};
};

For implementation, you can try looking at the driver for the adt7420, which seems to make use of an interrupt pin.

https://github.com/nrfconnect/sdk-zephyr/blob/v2.7.99-ncs1-1/drivers/sensor/adt7420/adt7420.c#L223-L231

Zephyr new device binding

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