This patch adds topology sof-apl-eq-dmic to help testing acoustical
audio capture via DMIC or work as example for other machine drivers. The
capture format is set as four channels, S32_LE, 48 kHz. The IIR EQ is
a 2nd order Butterworth high-pass with cut-off frequency at 50 Hz to
suppress non-audible lowest frequencies. The EQ provides additional
+20 dB gain to avoid the recording to sound too silent.
The IIR EQ or additional FIR EQ instance can when needed provide other
form factor specific equalization.
Signed-off-by: Seppo Ingalsuo <seppo.ingalsuo@linux.intel.com>
Curtis Malainey