On Thu, Dec 12, 2019 at 01:42:32AM +0000, John Stultz wrote: > From: Yu Chen <chenyu56@xxxxxxxxxx> > > This patch adds binding documentation to support usb hub and usb > data role switch of Hisilicon HiKey960 Board. > > Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > Cc: Rob Herring <robh+dt@xxxxxxxxxx> > Cc: Mark Rutland <mark.rutland@xxxxxxx> > CC: ShuFan Lee <shufan_lee@xxxxxxxxxxx> > Cc: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx> > Cc: Suzuki K Poulose <suzuki.poulose@xxxxxxx> > Cc: Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx> > Cc: Yu Chen <chenyu56@xxxxxxxxxx> > Cc: Felipe Balbi <balbi@xxxxxxxxxx> > Cc: Hans de Goede <hdegoede@xxxxxxxxxx> > Cc: Andy Shevchenko <andy.shevchenko@xxxxxxxxx> > Cc: Jun Li <lijun.kernel@xxxxxxxxx> > Cc: Valentin Schneider <valentin.schneider@xxxxxxx> > Cc: Guillaume Gardet <Guillaume.Gardet@xxxxxxx> > Cc: Jack Pham <jackp@xxxxxxxxxxxxxx> > Cc: linux-usb@xxxxxxxxxxxxxxx > Cc: devicetree@xxxxxxxxxxxxxxx > Signed-off-by: Yu Chen <chenyu56@xxxxxxxxxx> > Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx> > --- > v3: Reworked as usb-role-switch intermediary > > v7: Switched over to YAML dt binding description > --- > .../bindings/misc/hisilicon-hikey-usb.yaml | 85 +++++++++++++++++++ > 1 file changed, 85 insertions(+) > create mode 100644 Documentation/devicetree/bindings/misc/hisilicon-hikey-usb.yaml > > diff --git a/Documentation/devicetree/bindings/misc/hisilicon-hikey-usb.yaml b/Documentation/devicetree/bindings/misc/hisilicon-hikey-usb.yaml > new file mode 100644 > index 000000000000..1fc3b198ef73 > --- /dev/null > +++ b/Documentation/devicetree/bindings/misc/hisilicon-hikey-usb.yaml > @@ -0,0 +1,85 @@ > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) > +# Copyright 2019 Linaro Ltd. > +%YAML 1.2 > +--- > +$id: "http://devicetree.org/schemas/misc/hisilicon-hikey-usb.yaml#" > +$schema: "http://devicetree.org/meta-schemas/core.yaml#" > + > +title: HiKey960 onboard USB GPIO Hub > + > +maintainers: > + - John Stultz <john.stultz@xxxxxxxxxx> > + > +description: | > + Supports the onboard HiKey960 USB GPIO hub, which acts as a > + role-switch intermediary to detect the state of the USB-C > + port, to switch the hub into dual-role USB-C or host mode, > + which enables the onboard USB-A host ports. Honestly I'm torn between whatever works for you because this is pretty "special" dev board design and it should more accurately match the hardware design. I think we can do the later and it doesn't really need anything new. > + > + Schematics about the hub can be found here: > + https://github.com/96boards/documentation/raw/master/consumer/hikey/hikey960/hardware-docs/HiKey960_Schematics.pdf > + > +properties: > + compatible: > + items: > + - const: hisilicon,gpio_hubv1 As a whole this is HiSilicon specific, but really it is not. It's really just a hub, a mux, and connectors for which we have bindings for. I think you need to model the actual hub in DT. We have 2 ways already to describe hubs in DT: a I2C device or USB device. AIUI, the board looks something like this: ctrl -> mux --> hub -> type-a connector +-> type-c connector If the hub I2C is not used, then you could do something like this: ctrl { mux-controls = <&usb_gpio_mux>; connector@0 { // type C connector binding }; hub@1 { // USB device binding }; }; Or if I2C is used and the hub is under the I2C controller: ctrl { port@0 { mux-controls = <&usb_gpio_mux>; endpoint@0 { // mux state 0 remote-endpoint = <&usb_c_connector_port>; }; endpoint@1 { // mux state 1 remote-endpoint = <&usb_hub_port>; }; }; The only new bindings you really need are adding 'mux-controls' to the USB host controller and the hub binding (we already have a few). If the USB2 and USB3 signals come from 2 different host controller nodes, then I think it will need to look like the 2nd case regardless of I2C. (It's strange that USB3 was not routed to Type-C connector. Can you do USB2 on Type-C and USB3 on hub simultaneously? You need USB2 to enumerate, right?) > + > + typec-vbus-gpios: > + $ref: /schemas/types.yaml#/definitions/phandle > + description: phandle to the typec-vbus gpio This should be modeled as a GPIO regulator, and belongs as part of a connector node. See bindings/connector/usb-connector.txt. > + > + otg-switch-gpios: > + $ref: /schemas/types.yaml#/definitions/phandle > + description: phandle to the otg-switch gpio This would be the gpio-mux binding instead. > + > + hub-vdd33-en-gpios: > + $ref: /schemas/types.yaml#/definitions/phandle > + description: phandle to the hub 3.3v power enablement gpio This should be modeled as a GPIO regulator. What about the reset line on the hub? > + > + usb-role-switch: > + $ref: /schemas/types.yaml#/definitions/flag > + description: Support role switch. This normally is a controller property. Role switch is foreign to the hub, so doesn't really belong there for sure. > + > + port: > + description: | > + any connector to the data bus of this controller should be modelled > + using the OF graph bindings specified, if the "usb-role-switch" > + property is used. Note for this driver, two ports are supported, > + the first being the endpoint that will be notified by this driver, > + and the second being the endpoint that notifies this driver of a > + role switch. > + > + > +required: > + - compatible > + - typec-vbus-gpios > + - otg-switch-gpios > + - hub-vdd33-en-gpios > + - usb-role-switch > + - port > + > +additionalProperties: false > + > +examples: > + - | > + hisi_hikey_usb: hisi_hikey_usb { > + compatible = "hisilicon,gpio_hubv1"; > + typec-vbus-gpios = <&gpio25 2 GPIO_ACTIVE_HIGH>; > + otg-switch-gpios = <&gpio25 6 GPIO_ACTIVE_HIGH>; > + hub-vdd33-en-gpios = <&gpio5 6 GPIO_ACTIVE_HIGH>; > + usb-role-switch; > + > + port { > + #address-cells = <1>; > + #size-cells = <0>; > + > + hikey_usb_ep0: endpoint@0 { > + reg = <0>; > + remote-endpoint = <&dwc3_role_switch>; > + }; > + hikey_usb_ep1: endpoint@1 { > + reg = <1>; > + remote-endpoint = <&rt1711h_ep>; > + }; > + }; > + }; > -- > 2.17.1 >