q: USB_SET_TIMEOUT in ugen.

Hans Petter Selasky hselasky at c2i.net
Thu Mar 19 00:58:55 PDT 2009

On Thursday 19 March 2009, Weongyo Jeong wrote:
> ugen_default_read_callback:384: actlen=0, aframes=0
> ugen_default_read_callback:384: actlen=0, aframes=0
> ugen_read_clear_stall_callback:477: f=0xc4d5b000: stall cleared

One difference from the old ugen implementation is that a stall error does not 
cause any error to be returned to userland!

You could try to return a ZLP on errors. Try this patch:


If you need to distinguish a ZLP from a STALL, then you have to use the new 
libusb! Ugen is not meant to be a replacement for libusb!


More information about the freebsd-usb mailing list