On Tue, Dec 08, 2015 at 09:24:03PM -0600, Rob Herring wrote: > On Tue, Dec 08, 2015 at 10:58:48AM +0100, Arnd Bergmann wrote: > > On Tuesday 08 December 2015 10:50:49 Philipp Zabel wrote: > > > 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) */ > > > > Good point, I had not thought of that when I looked at the patches. > > > > Yes, let's do this way. I don't know if we ever implemented the simple > > patch to associate a USB device with a device_node, but if not, then > > let's do it now for this driver. A lot of people have asked for it in > > the past. > > Agreed. Also, some hubs have I2C buses as well, but I still think under > the USB bus is the right place. > > However, one complication here is often (probably this case) these > addtional signals need to be controlled before the device enumerates. > Yes, I did not find a way to let the USB bus code handle it, so I had to write a platform driver to do it -- Best Regards, Peter Chen -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html