Add bindings for the GE SUNH add-on connector. This is a physical, hot-pluggable connector that allows to attach and detach at runtime an add-on adding peripherals on non-discoverable busses. Signed-off-by: Luca Ceresoli <luca.ceresoli@xxxxxxxxxxx> --- Changed in v4: - rename 'nobus-devices' to 'devices' - use 'additionalProperties: true' for the 'devices' node (nodes are added by overlays) - document GPIO polarity - add '|' for descriptions to preserve line breaks - remove powergood-gpios (removed in hardware design) - Omit "/" node, not needed and cause of warnings - remove reference to v2 examples from example comment - remove unneeded "addon_connector" label from example Changed in v3: - change the layout to only add subnodes, not properties - add the 'nobus-devices' node description to hold devices not on any bus - add 'i2c-*' nodes for the I2C busses, using a i2c-parent phandle - and the 'dsi' node for the DSI bus - move the entire port@1 node to the overlay (not only the remote-endpoint property) - remove the overlay examples (Overlays in examples are not supported) - add more clarifying descriptions and comments for examples - some rewording This patch was added in v2. --- .../connector/ge,sunh-addon-connector.yaml | 177 +++++++++++++++++++++ MAINTAINERS | 5 + 2 files changed, 182 insertions(+) diff --git a/Documentation/devicetree/bindings/connector/ge,sunh-addon-connector.yaml b/Documentation/devicetree/bindings/connector/ge,sunh-addon-connector.yaml new file mode 100644 index 000000000000..68d7d7d7cf7e --- /dev/null +++ b/Documentation/devicetree/bindings/connector/ge,sunh-addon-connector.yaml @@ -0,0 +1,177 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/connector/ge,sunh-addon-connector.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: GE SUNH hotplug add-on connector + +maintainers: + - Luca Ceresoli <luca.ceresoli@xxxxxxxxxxx> + +description: | + Represent the physical connector present on GE SUNH devices that allows + to attach and detach at runtime an add-on adding peripherals on + non-discoverable busses. Peripherals on the add-on include I2C sensors + and a video bridge controlled via I2C. + + The connector has status GPIOs to notify the connection status to the CPU + and a reset GPIO to allow the CPU to reset all the peripherals on the + add-on. It also has I2C busses and a 4-lane MIPI DSI bus. + + Different add-on models can be connected, each having different + peripherals. For this reason each add-on has a model ID stored in a + non-volatile memory, which is accessed in the same way on all add-ons. + + Add-on removal can happen at any moment under user control and without + prior notice to the CPU, making all of its components not usable + anymore. Later on, the same or a different add-on model can be connected. + +properties: + compatible: + const: ge,sunh-addon-connector + + reset-gpios: + description: An output GPIO to reset the peripherals on the + add-on. Active low. + maxItems: 1 + + plugged-gpios: + description: An input GPIO that is asserted if and only if an add-on is + physically connected. Active low. + maxItems: 1 + + devices: + description: | + A container for devices not accessible via any data bus. Common use + cases include fixed and GPIO regulators, simple video panels and LED + or GPIO backlight devices. When not hot-pluggable, nodes such devices + are children of the root node. + + This node should not be present in the connector description in the + base device tree. It should be added by overlays along with a subnode + per device. + + type: object + additionalProperties: true + + dsi: + type: object + additionalProperties: false + + properties: + ports: + $ref: /schemas/graph.yaml#/properties/ports + + description: | + OF graph bindings modeling the MIPI DSI bus across the connector. The + connector splits the video pipeline in a fixed part and a removable + part. + + The fixed part of the video pipeline includes all components up to + the display controller and 0 or more bridges. The removable part + includes any bridges and any other components up to the panel. + + properties: + port@0: + $ref: /schemas/graph.yaml#/properties/port + description: + The last point of the non-removable part of the MIPI DSI bus + line. The remote-endpoint sub-node must point to the last + non-removable video component of the video pipeline. + + port@1: + $ref: /schemas/graph.yaml#/properties/port + description: + The first point of the removable part of the MIPI DSI bus + line. The remote-endpoint sub-node must point to the first + video pipeline component on the add-on. As it describes the + hot-pluggable hardware, the endpoint node cannot be filled + until an add-on is detected, so this node needs to be added + by a device tree overlay at runtime. + + required: + - port@0 + # port@1 is added by the overlay for any add-on using the DSI lines + + required: + - ports + +patternProperties: + '^i2c-(dbat|gp|btp)$': + description: + An I2C bus that goes through the connector. The adapter (and possibly + some clients) are on the fixed side. Add-ons that have any clients on + this bus have to be added by the add-on overlay, inside this node. + + $ref: /schemas/i2c/i2c-controller.yaml# + unevaluatedProperties: false + type: object + + properties: + i2c-parent: + $ref: /schemas/types.yaml#/definitions/phandle + description: + Phandle pointing to the I2C bus controller on the fixed side that + drives this bus + +required: + - compatible + - i2c-dbat + - i2c-gp + - i2c-btp + - dsi + +unevaluatedProperties: false + +examples: + # This is the description of the connector as it should appear in the + # main DTS describing the "main" board up to the connector. This is + # supposed to be used together with the overlays that describe the add-on + # components. + - | + #include <dt-bindings/gpio/gpio.h> + addon-connector { + compatible = "ge,sunh-addon-connector"; + reset-gpios = <&gpio1 1 GPIO_ACTIVE_LOW>; + plugged-gpios = <&gpio1 2 GPIO_ACTIVE_LOW>; + powergood-gpios = <&gpio1 3 GPIO_ACTIVE_HIGH>; + + i2c-dbat { + i2c-parent = <&i2c5_ch2>; + #address-cells = <1>; + #size-cells = <0>; + // device subnodes to be added by overlays + }; + + i2c-gp { + i2c-parent = <&i2c4>; + #address-cells = <1>; + #size-cells = <0>; + // device subnodes to be added by overlays + }; + + i2c-btp { + i2c-parent = <&i2c3>; + #address-cells = <1>; + #size-cells = <0>; + // device subnodes to be added by overlays + }; + + dsi { + ports { + #address-cells = <1>; + #size-cells = <0>; + + port@0 { + reg = <0>; + + endpoint { + remote-endpoint = <&previous_bridge_out>; + }; + }; + + // port@1 to be added by overlay + }; + }; + }; diff --git a/MAINTAINERS b/MAINTAINERS index cc40a9d9b8cd..b939284d1350 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -10270,6 +10270,11 @@ S: Maintained F: Documentation/devicetree/bindings/iio/pressure/honeywell,mprls0025pa.yaml F: drivers/iio/pressure/mprls0025pa* +HOTPLUG CONNECTOR FOR GE SUNH ADDONS +M: Luca Ceresoli <luca.ceresoli@xxxxxxxxxxx> +S: Maintained +F: Documentation/devicetree/bindings/connector/ge,sunh-addon-connector.yaml + HP BIOSCFG DRIVER M: Jorge Lopez <jorge.lopez2@xxxxxx> L: platform-driver-x86@xxxxxxxxxxxxxxx -- 2.34.1
