I appreciate you taking a look (even in spite of the dt_binding_check failure). On Thu, Jun 06, 2024 at 09:18:59AM -0600, Rob Herring wrote: > On Wed, Jun 05, 2024 at 06:12:44PM -0500, Danny Kaehn wrote: > > 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 > > There's no more gpio subnode. > Will fix. > > 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 | 105 +++++++++++++++++++++ > > 1 file changed, 105 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..0108f2e43c8c > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/i2c/silabs,cp2112.yaml > > @@ -0,0 +1,105 @@ > > +# 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 on the host controller > > Or hub ports. Just drop 'on the host controller'. > Will fix. > > + > > + i2c: > > + description: The SMBus/I2C controller node for the CP2112 > > + $ref: /schemas/i2c/i2c-controller.yaml# > > + unevaluatedProperties: false > > + > > + properties: > > + sda-gpios: > > + maxItems: 1 > > + > > + scl-gpios: > > + maxItems: 1 > > These are because I2C can be on any of the pins? It's a bit odd if they > aren't used as gpios. Probably should be pinmux, but that's overkill for > 2 pins. > I'm beginning to realize now that this may be a bit non-standard, but it did solve a stuck bus issue under some conditions. The CP2112's I2C controller is self-contained and can only be on the specific pins it is attached to (no pinmux, etc..). In this case, these properties are ment to specify additional gpio pins which are connected to the SCL and SDA lines (this then also assumes those are configured to be open drain / inputs to not interfere with the bus during normal operation). This was inspired by what is done ini2c-imx.yaml, but I realize this is a bit different due to using external pins rather than pinmuxing to the GPIOs. How I used this was to actually connect some of the CP2112's own GPIO pins to the SDA and SCL lines to be able to use those pins to recover the bus. This was able to solve a stuck bus under some real-world cases with the v2 of the CP2112 containing an errata which caused this semi-frequently. > > + > > + clock-frequency: > > + minimum: 10000 > > + default: 100000 > > + maximum: 400000 > > + > > + interrupt-controller: true > > + "#interrupt-cells": > > + const: 2 > > Where does the Unsure what you intended to ask here -- but the interrupt comes from the GPIO chip. It is unfortunately not a hardware interrupt, but is accomplished through polling. > > + > > + gpio-controller: true > > + "#gpio-cells": > > + const: 2 > > + > > + gpio-line-names: > > + minItems: 1 > > + maxItems: 8 > > + > > +patternProperties: > > + "-hog(-[0-9]+)?$": > > + 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>; > > + > > + cp2112: device@1 { > > + compatible = "usb10c4,ea90"; > > + reg = <1>; > > + > > + 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>; > > + }; > > + }; > > + > > + 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 > > Thanks, Danny Kaehn
