ep
desc
when configurations are set, or when interface settings change, the driver will enable or disable the relevant endpoints. while it is enabled, an endpoint may be used for i/o until the driver receives a disconnect from the host or until the endpoint is disabled.
the ep0 implementation (which calls this routine) must ensure that the hardware capabilities of each endpoint match the descriptor provided for it. for example, an endpoint named lqep2in-bulkrq would be usable for interrupt transfers as well as bulk, but it likely couldn't be used for iso transfers or for endpoint 14. some endpoints are fully configurable, with more generic names like lqep-arq. (remember that for USB, lqinrq means lqtowards the USB masterrq.)
returns zero, or a negative error code.
David Brownell <dbrownell@users.sourceforge.net>