[PATCH v1 v1 1/3] dt-bindings: i2c: add documentation for adding SiFive I2C driver

[Sagar Shrikant Kadam]

Add DT binding for OpenCore's based i2c device as found in
FU540 Chipset on HiFive Unleashed Platform (Rev A00).

The doc explains, how to add DT support for I2C devices.

Signed-off-by: Sagar Shrikant Kadam <sagar.kadam@xxxxxxxxxx>
---
 .../devicetree/bindings/i2c/i2c-sifive.txt         | 29 ++++++++++++++++++++++
 1 file changed, 29 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/i2c/i2c-sifive.txt

diff --git a/Documentation/devicetree/bindings/i2c/i2c-sifive.txt b/Documentation/devicetree/bindings/i2c/i2c-sifive.txt
new file mode 100644
index 0000000..2a0fc9b
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/i2c-sifive.txt
@@ -0,0 +1,29 @@
+SiFive I2C controller Device Tree Bindings
+-------------------------------------------------
+
+Required properties:
+
+- compatible		: Should be "sifive,<chipset>-i2c" for a particular chip or
+			  "sifive,i2c<ver>" for a general I2C block.
+			  For FU540 chipset the supported compatible string is "sifive,fu540-c000-i2c".
+- reg			: Physical base address and size of I2C registers map.
+- reg-names		: Should contain the resource reg names.
+- clocks		: Must reference the frequency given to the controller.
+- #address-cells	: Must be '1'.
+- #size-cells		: Must be '0'.
+- clock-frequency	: desired I2C bus clock frequency.
+
+Example:
+	i2c@10030000 {
+			compatible = "sifive,i2c0","sifive,fu540-c000-i2c";
+			reg = <0x0 0x10030000 0x0 0x1000>;
+			reg-names = "i2c-control";
+			clocks = <&tlclk>;
+			clock-frequency = <100000>;
+
+			reg-shift = <2>;
+			reg-io-width = <1>;
+
+			#address-cells = <1>;
+			#size-cells = <0>;
+	};
-- 
1.9.1