> Ok, I've just completed a thorough set of tests regarding my previously > described packet size problem with my USB ethernet (adsl) driver. It > appears to me that either a) UHCI just can't perform like OHCI, or b) > the UHCI driver has problems. My information is reported below. I'm > running on RedHat 7.2 with their stock kernel - 2.4.7-10.
Re (a), I think that's likely true, though that should not be affecting correctness. And for that kernel, I think (b) is true ... you should try this with a more recent kernel, with updated drivers for UHCI. Both of them have had updates since then. It's often good to compare _both_ UHCI drivers when you run into HCD dependent behaviors. We're trying to get away from having two, and that's one of the goals of the 2.5 conversion to use a new "hcd" framework and share code between all the HCDs. Interesting table of results ... :) > I would expect that from a USB driver's perspective, what he gets in > URBs should be the same regardless of what the HCD is. Is this > expectation wrong? That's the right expectation, certainly for control/bulk/interrupt transfers where the device data isn't timing-dependent. When you don't see the same results, it's some bug in the HCD. > I can accept the fact that for case #5 - we're simply running out of > time to receive all of the data. By the time we've queued up the URB > to get the last chunk of data, we've lost some data? Or, more likely, > we've lost some data somewhere from the first to the last chunk, but > since there is lots of data, the buffers are all full the urb until > the last one. I'm not clear what the failure mode is for #5. Those test parameters shouldn't matter, unless your device is (inappropriately) expecting bulk transfers to succeed with some particular timing. - Dave _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
