Kernel-4.18.0-80.el8_trf7970a

• Texas Instruments TRF7970A RFID/NFC/15693 Transceiver

Required properties:

• compatible: Should be “ti,trf7970a”.
• spi-max-frequency: Maximum SPI frequency (<= 2000000).
• interrupt-parent: phandle of parent interrupt handler.
• interrupts: A single interrupt specifier.
• ti,enable-gpios: One or two GPIO entries used for ‘EN’ and ‘EN2’ pins on the
  TRF7970A. EN2 is optional.
• vin-supply: Regulator for supply voltage to VIN pin

Optional SoC Specific Properties:

• pinctrl-names: Contains only one value - “default”.
• pintctrl-0: Specifies the pin control groups used for this controller.
• autosuspend-delay: Specify autosuspend delay in milliseconds.
• irq-status-read-quirk: Specify that the trf7970a being used has the
  “IRQ Status Read” erratum.
• en2-rf-quirk: Specify that the trf7970a being used has the “EN2 RF”
  erratum.
• vdd-io-supply: Regulator specifying voltage for vdd-io
• clock-frequency: Set to specify that the input frequency to the trf7970a is 13560000Hz or 27120000Hz

Example (for ARM-based BeagleBone with TRF7970A on SPI1):

&spi1 {

nfc@0 {
    compatible = "ti,trf7970a";
    reg = <0>;
    pinctrl-names = "default";
    pinctrl-0 = <&trf7970a_default>;
    spi-max-frequency = <2000000>;
    interrupt-parent = <&gpio2>;
    interrupts = <14 0>;
    ti,enable-gpios = <&gpio2 2 GPIO_ACTIVE_HIGH>,
              <&gpio2 5 GPIO_ACTIVE_HIGH>;
    vin-supply = <&ldo3_reg>;
    vdd-io-supply = <&ldo2_reg>;
    autosuspend-delay = <30000>;
    irq-status-read-quirk;
    en2-rf-quirk;
    clock-frequency = <27120000>;
};

};