These two Dell machines have been reported working well with
the ideapad model.

BugLink: http://bugs.launchpad.net/bugs/723676
Cc: stable@kernel.org
Tested-by: NDavid Chen <david.chen@canonical.com>
Signed-off-by: NDavid Henningsson <david.henningsson@canonical.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>