u-boot-brain/doc/device-tree-bindings/tpm2/tis-tpm2-spi.txt

ST33TPHF20 SPI TPMv2.0 bindings
-------------------------------

Required properties:
- compatible		: Should be "tcg,tpm_tis-spi"
- reg			: SPI Chip select

Optional properties:
- gpio-reset		: Reset GPIO (if not connected to the SoC reset line)
- spi-max-frequency	: See spi-bus.txt

Example:

	tpm@1 {
		compatible = "tcg,tpm_tis-spi";
		reg = <1>;
		spi-max-frequency = <10000000>;
	};