new file mode 100644
@@ -0,0 +1,69 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/i2c/tsd,mule-i2c-mux.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Theobroma Systems Mule I2C multiplexer
+
+maintainers:
+ - Farouk Bouabid <farouk.bouabid@cherry.de>
+ - Quentin Schulz <quentin.schulz@cherry.de>
+
+description: |
+ Theobroma Systems Mule is an MCU that emulates a set of I2C devices, among
+ which devices that are reachable through an I2C-mux. The devices on the mux
+ can be selected by writing the appropriate device number to an I2C config
+ register.
+
+
+ +--------------------------------------------------+
+ | Mule |
+ 0x18| +---------------+ |
+ -------->|Config register|----+ |
+ | +---------------+ | |
+ | V_ |
+ | | \ +--------+ |
+ | | \-------->| dev #0 | |
+ | | | +--------+ |
+ 0x6f| | M |-------->| dev #1 | |
+ ---------------------------->| U | +--------+ |
+ | | X |-------->| dev #2 | |
+ | | | +--------+ |
+ | | /-------->| dev #3 | |
+ | |__/ +--------+ |
+ +--------------------------------------------------+
+
+
+allOf:
+ - $ref: /schemas/i2c/i2c-mux.yaml#
+
+properties:
+ compatible:
+ const: tsd,mule-i2c-mux
+
+required:
+ - compatible
+
+unevaluatedProperties: false
+
+examples:
+ - |
+ i2c-mux {
+ compatible = "tsd,mule-i2c-mux";
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ i2c@0 {
+ reg = <0x0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ rtc@6f {
+ compatible = "isil,isl1208";
+ reg = <0x6f>;
+ };
+ };
+ };
+...
+