nfc: st-nci: Add device tree documentation for spi phy

Add st-nci-spi phy devicetree documentation

Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

1 files changed, 33 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/net/nfc/st-nci-i2c.txt b/Documentation/devicetree/bindings/net/nfc/st-nci-i2c.txt
new file mode 100644
index 000000000000..d707588ed734
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/nfc/st-nci-i2c.txt
@@ -0,0 +1,33 @@
+* STMicroelectronics SAS. ST NCI NFC Controller
+
+Required properties:
+- compatible: Should be "st,st21nfcb-i2c" or "st,st21nfcc-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
+- reset-gpios: Output GPIO pin used to reset the ST21NFCB
+
+Optional SoC Specific Properties:
+- pinctrl-names: Contains only one value - "default".
+- pintctrl-0: Specifies the pin control groups used for this controller.
+
+Example (for ARM-based BeagleBoard xM with ST21NFCB on I2C2):
+
+&i2c2 {
+
+	status = "okay";
+
+	st21nfcb: st21nfcb@8 {
+
+		compatible = "st,st21nfcb-i2c";
+
+		reg = <0x08>;
+		clock-frequency = <400000>;
+
+		interrupt-parent = <&gpio5>;
+		interrupts = <2 IRQ_TYPE_LEVEL_HIGH>;
+
+		reset-gpios = <&gpio5 29 GPIO_ACTIVE_HIGH>;
+	};
+};