On Fri, 3 Jan 2014, Eric Decker wrote: > On Fri, Jan 3, 2014 at 7:46 AM, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>wrote: > > > On Thu, 2 Jan 2014, Sarah Sharp wrote: > > > > > On Sun, Dec 29, 2013 at 06:28:20AM -0800, Eric Decker wrote: > > > > > > When I boot using a live USB (the kernel in this case is > > > > vmlinuz-3.11.0.12-generic), I see a couple of messages and then the > > kernel > > > > finishes (that is it doesn't hang). *Although the number of reattaches > > > > seems suspect.* > > > > By "reattaches", do you mean that the ELAN touchscreen disconnects from > > the USB bus and then reconnects? > > > > I see messages saying that the device is disconnected. It doesn't say why > so I don't > know if the the ELAN h/w is doing it or not. That was a "what" question, not "why". _What_ do you mean by "reattaches"? _What_ device is mentioned in those messages? > > If you get different behavior at different times using the same > > software, then most likely it's an intermittent hardware problem. > > > > So I took my current installed kernel.... > > Linux zot 3.11.0-15-generic #23-Ubuntu SMP Mon Dec 9 18:17:04 UTC 2013 > x86_64 x86_64 x86_64 GNU/Linux > > And rebooted like 4 times in a row. The behaviour is the same. Okay. I thought you said before that it had trouble finishing the boot process and that later on it was behaving itself. > The infinite loop happened with different s/w. It was a grub environment > booting a casper image of some type. The boot environment should not matter. I don't know what casper is. > I've looked at the log from the reboots mentioned above and they all look > the same. > > I think something is tickling the ELAN h/w in someway. I've been keeping > an eye on the logs and haven't seen > any misbehaviour on the part of the touch screen. > > Its not acting like it is an intermittent. It is acting like a complex > bug of somekind. One that we don't have > enough visibility on. > > I'm happy to try and find out what is going on but I am not far enough up > the learning curve to know what to look at. > > I've done embedded and h/w/s/w kinds of things for a long time (4th s/w > engineer at cisco) so know my way around just > not on this stuff. So if you point me in the right direction, that would > be a big help. > > > I've enclosed both a summary that I've pulled out from the syslog of the > reboots as well as the syslog.... You can try running usbmon (see the instructions in Documentation/usb/usbmon.txt) to see what happens during one of those disconnect/reconnect cycles. Alan Stern -- 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
