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 using the subnodes named "gpio" and "i2c", respectively. This is intended to be used in configurations where the CP2112 is permanently connected in hardware. Signed-off-by: Danny Kaehn <danny.kaehn@xxxxxxxxxx> --- Note -- Reviewed-By tags have been removed as suggested by Benjamin, since 1. It has been 6+ months since this binding was reviewed, and a lot can change upstream in that time 2. There has been some contention between using named child nodes to identify i2c and gpio nodes, and also making the driver implementing this binding compatible with ACPI, since names aren't significant for ACPI nodes, and ACPI names are always automatically uppercased. It has been suggested that perhaps the DT binding should use child nodes with addressable `reg` properties to identify the child nodes, instead of by name [1]. Of course, I acknowledge that other firmware languages and kernel details shouldn't impact DT bindings, but it also seems that there should be some consistent way to specify sub-functions like this accross DT and ACPI. Some additional commentary / requests for comment about the seemingly missing glue here can be found in [2]. Any comments from Rob/Krzysztof/other DT folks would be greatly appreciated [1] https://lore.kernel.org/all/ZBhoHzTr5l38u%2FkX@xxxxxxxxxxxxxxxxxx/ [2] https://lore.kernel.org/all/CAP+ZCCd0cD+q7=ngyEzScAte2VT9R00mqCQxB3K2TMbeg8UAfA@xxxxxxxxxxxxxx/ .../bindings/i2c/silabs,cp2112.yaml | 113 ++++++++++++++++++ 1 file changed, 113 insertions(+) create mode 100644 Documentation/devicetree/bindings/i2c/silabs,cp2112.yaml diff --git a/Documentation/devicetree/bindings/i2c/silabs,cp2112.yaml b/Documentation/devicetree/bindings/i2c/silabs,cp2112.yaml new file mode 100644 index 000000000000..a27509627804 --- /dev/null +++ b/Documentation/devicetree/bindings/i2c/silabs,cp2112.yaml @@ -0,0 +1,113 @@ +# 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 <kaehndan@xxxxxxxxx> + +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 on the host controller + + i2c: + description: The SMBus/I2C controller node for the CP2112 + $ref: /schemas/i2c/i2c-controller.yaml# + unevaluatedProperties: false + + properties: + sda-gpios: + maxItems: 1 + + scl-gpios: + maxItems: 1 + + clock-frequency: + minimum: 10000 + default: 100000 + maximum: 400000 + + gpio: + description: The GPIO controller node for the CP2112 + type: object + unevaluatedProperties: false + + properties: + interrupt-controller: true + "#interrupt-cells": + const: 2 + + gpio-controller: true + "#gpio-cells": + const: 2 + + gpio-line-names: + minItems: 1 + maxItems: 8 + + patternProperties: + "-hog(-[0-9]+)?$": + 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>; + + device@1 { + compatible = "usb10c4,ea90"; + reg = <1>; + + i2c { + #address-cells = <1>; + #size-cells = <0>; + sda-gpios = <&cp2112_gpio 0 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>; + scl-gpios = <&cp2112_gpio 1 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>; + + temp@48 { + compatible = "national,lm75"; + reg = <0x48>; + }; + }; + + cp2112_gpio: gpio { + gpio-controller; + interrupt-controller; + #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"; + }; + }; + }; + }; -- 2.25.1
