пн, 19 черв. 2023 р. о 17:45 Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> пише: > > On 19/06/2023 16:36, Svyatoslav Ryhel wrote: > > Document device tree schema which describes hot-pluggable via GPIO > > i2c bus. > > > > Signed-off-by: Svyatoslav Ryhel <clamor95@xxxxxxxxx> > > --- > > .../bindings/i2c/i2c-hotplug-gpio.yaml | 68 +++++++++++++++++++ > > 1 file changed, 68 insertions(+) > > create mode 100644 Documentation/devicetree/bindings/i2c/i2c-hotplug-gpio.yaml > > > > diff --git a/Documentation/devicetree/bindings/i2c/i2c-hotplug-gpio.yaml b/Documentation/devicetree/bindings/i2c/i2c-hotplug-gpio.yaml > > new file mode 100644 > > index 000000000000..74544687a2b8 > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/i2c/i2c-hotplug-gpio.yaml > > @@ -0,0 +1,68 @@ > > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) > > +%YAML 1.2 > > +--- > > +$id: http://devicetree.org/schemas/i2c/i2c-hotplug-gpio.yaml# > > +$schema: http://devicetree.org/meta-schemas/core.yaml# > > + > > +title: GPIO detected hot-plugged I2C bus > > + > > +maintainers: > > + - Michał Mirosław <mirq-linux@xxxxxxxxxxxx> > > + > > +description: | > > Do not need '|' unless you need to preserve formatting. > > > + Driver for hot-plugged I2C buses, where some devices on a bus > > + are hot-pluggable and their presence is indicated by GPIO line. > > + > > +properties: > > + $nodename: > > + pattern: "^i2c-(.*)?" > > Drop > > > + > > + compatible: > > + items: > > + - const: i2c-hotplug-gpio > > + > > + '#address-cells': > > + const: 1 > > + > > + '#size-cells': > > + const: 0 > > + > > + interrupts-extended: > > + minItems: 1 > > + > > + detect-gpios: > > + maxItems: 1 > > + > > + i2c-parent: > > + maxItems: 1 > > I don't understand this part. You built it as a complimentary device to > the I2C controller, but there is no such device as "hotplug I2C", right? > The GPIO is part of the controller and this is imaginary (virtual) device? > > Otherwise, where does the "detect-gpios" go? To the SoC? Then it is not > a real device... > This is basically GPIO controlled i2c bus duplication. Transformer has 2 ECs, one for pad and one for dock. They both are present on the i2c bus, but the dock is not always present. Its presence is determined by a GPIO. Once a dock is present, GPIO triggers bus duplication and all devices described on that bus are probed, same when detaching the dock. Detecting GPIO and interrupt GPIO is the same GPIO. > > + > > +required: > > + - compatible > > + - "#address-cells" > > + - "#size-cells" > > Use consistent quotes (' or "). > > > + - interrupts-extended > > + - detect-gpios > > + - i2c-parent > > + > > +unevaluatedProperties: false > > + > > +examples: > > + - | > > + /* > > + * Asus Transformers use I2C hotplug for attachable dock keyboard > > + */ > > + #include <dt-bindings/gpio/gpio.h> > > + #include <dt-bindings/interrupt-controller/irq.h> > > + > > + i2c-dock { > > + compatible = "i2c-hotplug-gpio"; > > + > > + #address-cells = <1>; > > + #size-cells = <0>; > > + > > + interrupts-extended = <&gpio 164 IRQ_TYPE_EDGE_BOTH>; > > + detect-gpios = <&gpio 164 1>; > > You forgot define. > Define GPIO name or high/low? May you specify? Best regards, Svyatoslav R. > > + > > + i2c-parent = <&{/i2c@7000c400}>; > > Use normal phandles/labels like entire DTS, not full paths or node names. > > > + }; > > +... > > Best regards, > Krzysztof >
