On Wed, 20 Jun 2007, Pete Zaitcev wrote: > On Wed, 20 Jun 2007 14:53:24 -0400 (EDT), Alan Stern <[EMAIL PROTECTED]> > wrote: > > > > https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=243798 > > > > This bug is easy to analyze because there's only one person > > reporting problems and he provided a detailed usbmon log. The > > fingerprint reader includes a builtin hub, and that hub crashes every > > time the system tries to resume port 1. > > He's not the only one. I coaxed the earlier reporter into getting me one > and started reading yesterday, but haven't completed it. Alan, I use your > cheat sheet a lot, thanks! Here's the bug where I looked: > https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=239507 > > This looks like a rare case where bugs are truly duplicate. I'm going > to dup Dawid's bug into Kevin's, just based on the bug number.
It does look exactly the same. > Anyway, what is the solution here? Blacklist the hub by VID:PID (0b97:7762)? 0b97:7761 actually. And bcdDevice = 0110 -- maybe they'll fix it in a later revision. > But where, in hub.c? Right now we don't have any mechanism for coping with a hub that is unable to resume a port (which implies that we better not ever suspend that port). In the end, I think we'll have to treat such hubs as though CONFIG_USB_SUSPEND were turned off. That means never suspending any of the hub's ports, but suspending the hub itself would probably be okay. It's not clear how to make this work with autosuspend. Right now the core will autosuspend a hub when all of its children are suspended. But in this case that will never happen, even though the children might very well be unused. Should we worry about this? Such devices (and there probably are a lot of them if Dell uses them in the Latitude line) will drain power from laptops unless the user does something drastic, like unbinding the buggy hub from the hub driver. I don't know what the best approach is. What do you think? Alan Stern ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
