*I plug in my Nexus 4*
[ 344.706593] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 344.915465] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 345.124305] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 345.333215] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 345.539090] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 345.744970] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 345.950840] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 346.159660] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 346.368581] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 346.577413] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 346.783342] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 346.992207] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 347.198090] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 347.406966] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 347.612835] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 347.821719] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 348.030584] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 348.239462] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 348.445305] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 348.654210] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 348.860092] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 349.068964] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 349.274835] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 349.483715] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 349.689585] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 349.898466] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 350.107340] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 350.313221] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 350.519095] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 350.727961] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 350.933808] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 351.142722] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 351.351590] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 351.560432] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 351.769342] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 351.978186] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 352.184092] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 352.389963] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 352.595846] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 352.801721] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 353.010591] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 353.216474] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 353.422341] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 353.631216] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 353.840096] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 354.048979] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 354.254846] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 354.460721] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 354.666612] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 354.875483] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 355.084353] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 355.290231] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 355.499102] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 355.707922] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 355.913852] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 356.122721] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 356.331594] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 356.537471] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 356.746350] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 356.955221] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 357.161096] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 357.366970] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 357.572853] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 357.781743] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 357.990598] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 358.199472] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 358.408349] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 358.617228] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 358.826097] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 359.031980] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 359.240847] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 359.449722] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 359.658596] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 359.864432] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 360.070348] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 360.276225] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 360.485099] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 360.693977] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 360.899857] hub 7-0:1.0: unable to enumerate USB device on port 1
[ 361.108730] hub 7-0:1.0: unable to enumerate USB device on port 1
===================== *unplug nexus 4* =====================