On Fri, 19 Jan 2007, Jon Smirl wrote: > On 1/19/07, David Brownell <[EMAIL PROTECTED]> wrote: > > On Friday 19 January 2007 1:30 pm, Alan Stern wrote: > > > On Fri, 19 Jan 2007, David Brownell wrote: > > > > > > > On Friday 19 January 2007 9:17 am, Jon Smirl wrote: > > > > > > > > > There is still the unexplained case of it working ok when plugged into > > > > > a hub, it only fails on a root controller. But it failed on both ICH4 > > > > > and ICH5. It works on both my USB 1.0 and USB 2.0 hubs. > > > > > > > > Sorry if this came out in earlier discussion ... but has it been > > > > established that this isn't a UHCI-specific issue? Assuming this > > > > is a full-speed device, did you test with OHCI root hubs? > > > > > > I think it unlikely that this is UHCI-specific, but it's always a good > > > idea to make certain... > > > > Exactly. > > I can sacrifice my device for testing purposes. I have motherboard > audio available and I might buy something new. Are either of you close > to Wellesley, MA or I can mail it.
I work in Cambridge, as perhaps you can guess from my email address. If you want to drive over we ought to be able to settle on a weekend. Or you might find that mailing is easier. And BTW, I don't anticipate any destructive testing. :-) You can have the device back at the end and it should continue to work as well (or as poorly) as before. Apart from this, I've had an idea which might help solve this and a lot of similar problems. The idea is to try doing a reset automatically during resume if the device fails to respond, or if it disconnects and then reconnects within (say) 100 ms. The locking issue shouldn't be serious -- in fact, it might be enough to say that you can call usb_reset_device without holding the device lock provided you do it as part of a device resume. I believe that will still provide all the mutual exclusion we need. Adding code to do this won't be too hard, since most of the infrastructure is already in place. It also dovetails nicely with the "persist across power loss during suspend" patch, which I plan to submit in the not-too-distant future. Any thoughts? Alan Stern ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys - and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
