On Fri 090515, Alan Stern wrote: > On Fri, 15 May 2009, Karl Hiramoto wrote: > > > Dave Higton wrote: > > > On Thursday May 14, Ethan wrote: [..........] > > > > I think windows has the same issue: > > http://www.techtalkz.com/microsoft-device-drivers/243707-usb-problem-when-using-philips-isp1521-based-hub.html > > The problem described in that thread appears to be a genuine bug. In > short, ehci-hcd doesn't do a clear-TT-buffer when a low/full-speed > async URB is unlinked. When that happens the buffer remains busy > indefinitely, and when all the buffers are busy the hub won't work > right. this mail seems to answer my just posted question (emails have crossed :) it is also interesting to read that Microsoft wont fix this for XP and Win2k3 since "it only affects devices connected to external hubs"..... part of my question is still very intersting to me: are some hub chips known to be "better" in this respect or is it simply a matter of playing around long enough to get all TT buffers locked? Karl -- D.I. Karl Kiniger mailto:karl.kiniger@xxxxxxxxxx Tel: (++43) 7682-3800-710 Voip(GE): 1662 710 Fax: (++43) 7682-3800-47 C: +43 6991 3800 710 - GE Medical Systems Kretztechnik GmbH & Co OHG - Tiefenbach 15 – A-4871 Zipf Landesgericht Wels FN 222387s – UID (VAT-ID): ATU54086108 - DVR: 2111103 – ARA: 12816 Persönlich haftende Gesellschafterin: GE Medical Systems Kretztechnik GmbH Tiefenbach 15 – A-4871 Zipf - Landesgericht Wels FN 218689b -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html