Comment 75 for bug 925760

For a permanent workaround, create the file /etc/modprobe.d/ums-realtek.conf with the following content:

options ums_realtek ss_en=0

or execute this command:

sudo sh -c 'echo "options ums_realtek ss_en=0" > /etc/modprobe.d/ums-realtek.conf'

I think this bug could be declared fixed once the ss_en option is disabled by default. This can be done either by shipping a modprobe conffile or by changing the default value of the option in the kernel source.

The 'ss_en' switch controls 'selective suspend', e.g. suspending parts of the card reader which are not used. Typically only one card slot is in use at any time, so disabling would slightly decrease power consumption when a card is inserted. When there is no card, the reader would power down through the normal USB suspend mechanism.