i have this scenario in a similar sabrelite custom board (without usb hub onboard chip), and kernel 3,14.
USB connector ---> USB external 2.0 HUB (non powered)
On the hub i have a small keyboard and filesystem stick.
Consumption on VBUS is, as above, 80mA. VBUS at connector is 4,98V.
I connect now 2 USB powered spekers on the hub (low volume).
VBUS moves to 4,96, current to 140mA abt. But i get a disconnect message about the
usb filesystem stick from the kernel.
localhost login: usb 2-1: USB disconnect, device number 2 usb 2-1.1: USB disconnect, device number 3
I don't have any evidence of VBUS issues, board can source 1050mA.
Seems a disconenct due to the data line signals.
There could be some driver issue afayk ? Or it could be some host register to set better ?
Every help is really appreciated.