Patent ID: 8180947
Filing Date: 2012-05-15
Classification: G06F

Abstract:
1. A USB (Universal Serial Bus) controller device having OTG (On-The-Go) functionality, the USB controller device comprising: a host control unit having an EHCI (Enhanced Host Controller Interface) compliant host controller adapted to implement host functionality to perform data transfer to and/or from at least one USB peripheral device; a device control unit adapted to implement device functionality to perform data transfer to and/or from a USB host device; a port multiplexer adapted to assign a physical port to either said host control unit or said device control unit, wherein said port multiplexer comprises a port multiplexer capability register adapted to store capability information indicating functional capabilities of said port multiplexer, said port multiplexer capability register being accessible by software; and an OTG control unit adapted to implement an OTG state machine to control operation of said host control unit, wherein said OTG control unit is adapted to implement said OTG state machine partly in hardware and partly in software; wherein said OTG control unit comprises an OTG control register adapted to hold control information to control operation of said OTG control unit, said OTG control register being accessible by software; wherein said OTG control register is writeable by software; wherein said OTG control unit further comprises an OTG status register adapted to hold status information of said OTG control unit, said OTG status register being readable by software; and wherein said OTG control unit is adapted to cause a software driver to read said OTG status register in response to a change of said status information.