(switched to email. Please respond via emailed reply-to-all, not via the bugzilla web interface). On Fri, 19 Mar 2010 11:40:10 GMT bugzilla-daemon@xxxxxxxxxxxxxxxxxxx wrote: > http://bugzilla.kernel.org/show_bug.cgi?id=15580 > > Summary: ehci_hcd has to be reloaded after disconnect/connect > cycle of USB audio card > Product: Drivers > Version: 2.5 > Kernel Version: 2.6.31 to 2.6.33 > Platform: All > OS/Version: Linux > Tree: Mainline > Status: NEW > Severity: normal > Priority: P1 > Component: USB > AssignedTo: greg@xxxxxxxxx > ReportedBy: eusou15@xxxxxxxxx > Regression: No > > > Created an attachment (id=25609) > --> (http://bugzilla.kernel.org/attachment.cgi?id=25609) > lsusb -vvv > > Hi, > > I have a WinTV NOVA-T DVB-T USB2 adapter (dvb_usb_dib0700) and a Native > Instruments Audio4DJ USB sound card (snd-usb-caiaq). > > Both devices work wonderfully when I come from a fresh boot (I can > watch tv with the audio routed through the sound card). However, once > I disconnected the audio card and reconnect again, I get this regular > but not periodic interference on the audio card. > By "regular and not periodic" I mean that the time elapsed between > each interference is random, from 0.5 to 30 seconds, but it keeps > happening. The interference is a kind of crack and pop which affects > all output channels of the audio card. > > >From now on (until I fresh boot again), I can reconnect the audio card > as many times as I want, rmmod and modprobe its module again and I > always get the interference. Note that unplugging and plugging the DVB > adapter makes no difference, and if I fresh boot, connect both > devices, disconnect the DVB card and reconnect, I do not get > interference - only when I do the same with the audio card. > > After much research I found the culprit - apparently if I rmmod and > modprobe the ehci_usb device the interference is gone without having > to fresh boot (of course before this I unload the modules for the dvb > and audio devices). > > I was to able to reproduce this problem in kernels 2.6.31 to 2.6.33 (I > haven't tried any others). I WAS NOT able to reproduce on a ICH4 > laptop I have. > > In conclusion: > > Procedure 1: > - fresh boot > - connect both devices > - everything works OK > > Procedure 2: > - (same as Procedure 1) > - disconnect audio card and reconnect > - interference starts until I reload all relevant modules and ehci_hcd > > Procedure 3: > - (same as Procedure 1) > - disconnect DVB-T card and reconnect > - everything works OK > > My laptop is a Lenovo T400. > > Attached are the lsusb and lspci -vvv. Please let me know if you need > any more information. > -- 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
