Add functions that detecting signal frequency through spectrum
analyzing.
Signed-off-by: Lu, Han <han.lu@intel.com>
Signed-off-by: Liam Girdwood <liam.r.girdwood@intel.com>
Signed-off-by: Bernard Gautier <bernard.gautier@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>