dt-bindings: hwmon: Add TI TPS23861 bindings

Document bindings for the Texas Instruments TPS23861 driver.
Signed-off-by: Robert Marko <robert.marko@sartura.hr>
Cc: Luka Perkov <luka.perkov@sartura.hr>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20210121134434.2782405-1-robert.marko@sartura.hrSigned-off-by: Guenter Roeck <linux@roeck-us.net>

Documentation/devicetree/bindings/hwmon/ti,tps23861.yaml

+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+
+$id: http://devicetree.org/schemas/hwmon/ti,tps23861.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: TI TPS23861 PoE PSE
+
+maintainers:
+  - Robert Marko <robert.marko@sartura.hr>
+
+description: |
+  The TPS23861 is a IEEE 802.3at Quad Port Power-over-Ethernet PSE Controller.
+
+  Datasheets:
+  https://www.ti.com/lit/gpn/tps23861
+
+
+properties:
+  compatible:
+    enum:
+      - ti,tps23861
+
+  reg:
+    maxItems: 1
+
+  shunt-resistor-micro-ohms:
+    description: The value of curent sense resistor in microohms.
+    default: 255000
+    minimum: 250000
+    maximum: 255000
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    i2c {
+          #address-cells = <1>;
+          #size-cells = <0>;
+
+          tps23861@30 {
+              compatible = "ti,tps23861";
+              reg = <0x30>;
+              shunt-resistor-micro-ohms = <255000>;
+          };
+    };