Borchers, Al (C)(STP) wrote:
Dave --


If you have a driver for a dual-speed device, the
driver needs to pay attention to high speed interrupt
transfers.


Can you elaborate? What do I need to pay attention to?

Mostly just making urb->interval work right:


 Full/low speed:       urb->interval = desc->bInterval;
 High speed:           urb->interval = (1 << desc->bInterval);

And of course:

ISO (full/high): urb->interval = (1 << desc->bInterval);

And if you're working in time values, adjust appropriately:
high speed talks in micro-frames (125 usec), otherwise it's
in frames (8 uframes == 1000 usec == 1 msec).

- Dave



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