Comment 9 for bug 1298171

Checked, those stuff doesn't exist under the /sys/class directory:

root@arndale:/sys/class # ls
ata_device
ata_link
ata_port
bdi
block
dma
firmware
graphics
i2c-adapter
input
mdio_bus
mem
misc
mmc_host
net
regulator
scsi_device
scsi_disk
scsi_generic
scsi_host
thermal
timed_output
tty
udc
vc
video4linux
vtconsole