CHIP-linux-libre/Documentation/devicetree/bindings/net/nfc/st21nfca.txt

* STMicroelectronics SAS. ST21NFCA NFC Controller

Required properties:
- compatible: Should be "st,st21nfca-i2c".
- clock-frequency: I²C work frequency.
- reg: address on the bus
- interrupt-parent: phandle for the interrupt gpio controller
- interrupts: GPIO interrupt to which the chip is connected
- enable-gpios: Output GPIO pin used for enabling/disabling the ST21NFCA

Optional SoC Specific Properties:
- pinctrl-names: Contains only one value - "default".
- pintctrl-0: Specifies the pin control groups used for this controller.
- ese-present: Specifies that an ese is physically connected to the nfc
controller.
- uicc-present: Specifies that the uicc swp signal can be physically
connected to the nfc controller.

Example (for ARM-based BeagleBoard xM with ST21NFCA on I2C2):

&i2c2 {

	status = "okay";

	st21nfca: st21nfca@1 {

		compatible = "st,st21nfca-i2c";

		reg = <0x01>;
		clock-frequency = <400000>;

		interrupt-parent = <&gpio5>;
		interrupts = <2 IRQ_TYPE_LEVEL_LOW>;

		enable-gpios = <&gpio5 29 GPIO_ACTIVE_HIGH>;

		ese-present;
		uicc-present;
	};
};