On Mon, Oct 19, 2026 at 09:24:50AM +0000, Jamin Lin wrote: > usb_claim_port() inserts a usb-hub when a device is plugged in and only > one port is still free, so that more devices can follow. That is what a > host controller with root ports wants.
Ah, well, not really. It's there mostly for historical reasons. The emulated usb hub supports only usb 1.1, so for newer host controllers (ehci / xhci) it does not make much sense and the better approach is to add more host controllers if needed. Which should rarely actually be the case though given that xhci supports up to 15 root ports. So if this gets into the way I'm wondering whenever the better approach here is to remove this altogether. You can still add an USB hub manually of needed, IIRC there is (or was?) some board with a single-port OHCI where you actually need a hub if you want plug in both usb keyboard and usb mouse. It just would not be automatic any more. Alternative idea would be to add the config option, but only enable the automatic hub logic for actual usb 1.1 controllers (ohci / uhci), where it does not matter much for devices whenever they are plugged into an root port or hub port. take care, Gerd
