[PATCH v2 3/4] dt-bindings: uart-routing: Add binding for StarFive JHB100 UART routing

[Changhuang Liang <changhuang.liang@starfivetech.com>]

Add device tree binding for the StarFive JHB100 UART routing controller.
This controller allows dynamic routing of inputs between built-in UARTs
and physical serial I/O ports, enabling use cases such as Host <-> BMC
communication via UARTs.

The clocks property exists in the hardware, but the driver does not use
it.

Signed-off-by: Changhuang Liang <changhuang.liang@starfivetech.com>
---
 .../uart-routing/starfive,uart-routing.yaml   | 46 +++++++++++++++++++
 1 file changed, 46 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/uart-routing/starfive,uart-routing.yaml

diff --git a/Documentation/devicetree/bindings/uart-routing/starfive,uart-routing.yaml b/Documentation/devicetree/bindings/uart-routing/starfive,uart-routing.yaml
new file mode 100644
index 000000000000..1977f2ed20a6
--- /dev/null
+++ b/Documentation/devicetree/bindings/uart-routing/starfive,uart-routing.yaml
@@ -0,0 +1,46 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/uart-routing/starfive,uart-routing.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: StarFive JHB100 UART Routing Controller
+
+maintainers:
+  - Changhuang Liang <changhuang.liang@starfivetech.com>
+
+description: |
+  The StarFive JHB100 UART routing controller allows dynamic routing of the
+  inputs for the built-in UARTs and the physical serial I/O ports.
+
+  This allows, for example, connecting the output of one UART to another
+  UART, which can be used to enable Host <-> BMC communication over UARTs,
+  e.g. to give the BMC access to the Host's serial console.
+
+properties:
+  compatible:
+    const: starfive,jhb100-uart-routing
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+  resets:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - resets
+
+additionalProperties: false
+
+examples:
+  - |
+    uart-routing@11a42a00 {
+        compatible = "starfive,jhb100-uart-routing";
+        reg = <0x11a42a00 0x100>;
+        resets = <&per0crg 74>;
+    };
-- 
2.25.1