On Mon, 12 Dec 2016, John Stultz wrote: > From: Chen Yu <cheny...@huawei.com> > > The Hi6220's usb controller is limited in that it does not > support "Split Transactions", so it does not support communicating > with low-speed and full-speed devices behind a high-speed hub. > > Thus it requires a quirk so that we can manually drop the usb > speed when low/full-speed are attached, and bump back to high > speed when they are removed.
Just out of curiosity (I know nothing about this hardware), what happens if there is a high-speed hub plugged into the host controller and both a high-speed and a full-speed device plugged into the hub? Do you end up forcing the high-speed device to run at full speed? Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
