problem when porting udc code!

[王永来]

hello
I have compiled the udc code successfully,but after the kernel booting,I
just see there are a lot of interrupts says "ep0 Busy",it's in handle_ep0
function,so I tracked the kernel,and found the interrupt is introduced by
ep0 FIFO ERROR,but even if I clear that,I would found the same
error.Iguessed that maybe caused by BP(I am not familiar with
BP),maybe BP send
siganl to UDC?
regards
dotmonkey