[PATCH v13 1/3] dt-bindings: i2c: Add CP2112 HID USB to SMBus Bridge

From: Danny Kaehn

Date: Tue Jan 27 2026 - 10:05:39 EST


This is a USB HID device which includes an I2C controller and 8 GPIO pins.

The binding allows describing the chip's gpio and i2c controller in DT,
with the i2c controller being bound to a subnode named "i2c". This is
intended to be used in configurations where the CP2112 is permanently
connected in hardware.

Signed-off-by: Danny Kaehn <danny.kaehn@xxxxxxxxxx>
---
.../devicetree/bindings/i2c/silabs,cp2112.yaml | 100 +++++++++++++++++++++
1 file changed, 100 insertions(+)

diff --git a/Documentation/devicetree/bindings/i2c/silabs,cp2112.yaml b/Documentation/devicetree/bindings/i2c/silabs,cp2112.yaml
new file mode 100644
index 000000000000..a204adfe57b3
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/silabs,cp2112.yaml
@@ -0,0 +1,100 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/i2c/silabs,cp2112.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: CP2112 HID USB to SMBus/I2C Bridge
+
+maintainers:
+ - Danny Kaehn <danny.kaehn@xxxxxxxxxx>
+
+description:
+ The CP2112 is a USB HID device which includes an integrated I2C controller
+ and 8 GPIO pins. Its GPIO pins can each be configured as inputs, open-drain
+ outputs, or push-pull outputs.
+
+properties:
+ compatible:
+ const: usb10c4,ea90
+
+ reg:
+ maxItems: 1
+ description: The USB port number
+
+ interrupt-controller: true
+ "#interrupt-cells":
+ const: 2
+
+ gpio-controller: true
+ "#gpio-cells":
+ const: 2
+
+ gpio-line-names:
+ minItems: 1
+ maxItems: 8
+
+ i2c:
+ description: The SMBus/I2C controller node for the CP2112
+ $ref: /schemas/i2c/i2c-controller.yaml#
+ unevaluatedProperties: false
+
+ properties:
+ clock-frequency:
+ minimum: 10000
+ default: 100000
+ maximum: 400000
+
+patternProperties:
+ "-hog(-[0-9]+)?$":
+ type: object
+
+ required:
+ - gpio-hog
+
+required:
+ - compatible
+ - reg
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/interrupt-controller/irq.h>
+ #include <dt-bindings/gpio/gpio.h>
+
+ usb {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ cp2112: device@1 {
+ compatible = "usb10c4,ea90";
+ reg = <1>;
+
+ gpio-controller;
+ interrupt-controller;
+ #interrupt-cells = <2>;
+ #gpio-cells = <2>;
+ gpio-line-names = "CP2112_SDA", "CP2112_SCL", "TEST2",
+ "TEST3","TEST4", "TEST5", "TEST6";
+
+ fan-rst-hog {
+ gpio-hog;
+ gpios = <7 GPIO_ACTIVE_HIGH>;
+ output-high;
+ line-name = "FAN_RST";
+ };
+
+ i2c {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ sda-gpios = <&cp2112 0 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>;
+ scl-gpios = <&cp2112 1 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>;
+
+ temp@48 {
+ compatible = "national,lm75";
+ reg = <0x48>;
+ };
+ };
+ };
+ };

--
2.25.1