Hi Peter, Am Dienstag, den 08.12.2015, 09:37 +0800 schrieb Peter Chen: > Add dt-binding documentation for generic onboard USB HUB. > > Signed-off-by: Peter Chen <peter.chen@xxxxxxxxxxxxx> > --- > .../bindings/usb/generic-onboard-hub.txt | 28 ++++++++++++++++++++++ > 1 file changed, 28 insertions(+) > create mode 100644 Documentation/devicetree/bindings/usb/generic-onboard-hub.txt > > diff --git a/Documentation/devicetree/bindings/usb/generic-onboard-hub.txt b/Documentation/devicetree/bindings/usb/generic-onboard-hub.txt > new file mode 100644 > index 0000000..ea92205 > --- /dev/null > +++ b/Documentation/devicetree/bindings/usb/generic-onboard-hub.txt > @@ -0,0 +1,28 @@ > +Generic Onboard USB HUB >+ > +Required properties: > +- compatible: should be "generic-onboard-hub" This something we don't have to define ad-hoc. The hub hangs off an USB controller, right? The "Open Firmware recommended practice: USB" document already describes how to represent USB devices in a generic manner: http://www.firmware.org/1275/bindings/usb/usb-1_0.ps Is there a reason not to reuse this? The usb hub node would be a child of the usb controller node, and it could use compatible = "usb,class9"; /* bDeviceClass 9 (Hub) */ > +Optional properties: > +- clocks: the input clock for HUB. > + > +- clock-names: Should be "external_clk" Is clock-names necessary for a single clock? > +- hub-reset-gpios: Should specify the GPIO for reset. I'd prefer that to be just "reset-gpios", it is the only reset property in the hub node after all. And use the GPIO_ACTIVE_HIGH/LOW flags to indicate polarity. > +- hub-reset-active-high: the active reset signal is high, if this property is > + not set, the active reset signal is low. Then this could be dropped. > +- hub-reset-duration-us: the duration for assert reset signal, the time unit > + is microsecond. And consequently, this could just be called "reset-duration-us". It might make sense to define the same for other reset GPIOs, too. The Freescale FEC, for example, has "phy-reset-duration" (in ms) already. > + > +Example: > + > + usb_hub1 { > + compatible = "generic-onboard-hub"; > + clocks = <&clks IMX6QDL_CLK_CKO>; > + clock-names = "external_clk"; > + hub-reset-gpios = <&gpio7 12 0>; > + hub-reset-active-high; > + hub-reset-duration-us = <2>; > + }; best regards Philipp -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
