These controllers say "unknown" for their speed in sysfs, which
obviously isn't correct.
Reported-by: Kurt Garloff <garloff@novell.com>
Cc: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: David Vrabel <david.vrabel@csr.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>