Comment 73 for bug 925760

The "ss_en" option of the ums_realtek driver seems to solve this for me as I described in post #3 at http://askubuntu.com/questions/132100/errors-in-dmesg-test-wp-failed-assume-write-enabled
modinfo ums_realtek shows as options:

parm: auto_delink_en:enable auto delink (int)
parm: ss_en:enable selective suspend (int)
parm: ss_delay:seconds to delay before entering selective suspend (int)

Empirical testing shows that ss_delay value is how often the error will appear in the console.
Disabling the suspend with ss_en=0 still allows the reader to work but not suspend/wake every ss_delay amount of seconds.

This fix is still working for me as of Raring Ringtail with 64bit kernel 3.8.0-1-generic #5-Ubuntu