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+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/serial/ni,ni16550.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: NI 16550 asynchronous serial interface (UART)
+
+maintainers:
+ - Brenda Streiff <brenda.streiff@ni.com>
+
+allOf:
+ - $ref: serial.yaml#
+
+properties:
+ compatible:
+ const: ni,ni16550
+
+ reg:
+ maxItems: 1
+
+ interrupts:
+ maxItems: 1
+
+ clocks:
+ maxItems: 1
+
+ ni,serial-port-mode:
+ description: Indicates whether this is an RS-232 or RS-485 serial port.
+ $ref: /schemas/types.yaml#/definitions/string
+ enum: [ RS-232, RS-485 ]
+ default: RS-485
+
+required:
+ - compatible
+ - reg
+ - interrupts
+
+unevaluatedProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/interrupt-controller/irq.h>
+ serial@80000000 {
+ compatible = "ni,ni16550";
+ reg = <0x80000000 0x8>;
+ interrupts = <0 30 IRQ_TYPE_LEVEL_HIGH>;
+ clocks = <&clk_uart>;
+ ni,serial-port-mode = "RS-232";
+ };
+...