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Re: Potential problem with reading data from usb devices with ugen(4)



On 12/09/15 07:47, Brian Buhrow wrote:
	hello.  Continuing this thread, I believe I've asked this question
before, but I don't think I've been as specific aboutit.

	How should I go about generating a zero length packet through our USB
stack?  It looks like you can just send a 0 length usb transfer down the
FreeBSD stack, and Darwin and Linux have ioctls to accomplish this task.


See USBD_FORCE_SHORT_XFER - ugen needs to be taught about it.

When I send a zero-length transfer down the NetBSD stak, I get panics in
the uhci(4) and ehci(4) drivers.  Specifically, the chain allocators get
confused about the fact that the lengths of the xfer are zero.

send-pr please.

Hopefully I've fixed these on my branch.

Nick


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