From mboxrd@z Thu Jan  1 00:00:00 1970
From: Raymond Yau <superquad.vortex2@gmail.com>
Subject: Re: Mixer volume/decibel mapping
Date: Wed, 26 May 2010 07:00:22 +0800
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2010/5/25 Clemens Ladisch <clemens@ladisch.de>

> Raymond Yau wrote:
> > I have doubt about DECLARE_TLV_DB_LINEAR(ak4396_db_scale,
> TLV_DB_GAIN_MUTE, 0);
> >
> > since the datasheet mention that dB range is only -48dB to 0dB
> >
> > ATT = 20 log10 (ATT_DATA / 255) [dB]
> >
> > How can AK4396 has scale of -inf DB to 0dB in the driver code  ?
>
> When ATT_DATA = 0, there is no output, which is an attenuation of -inf.
> The next value, ATT_DATA = 1, results in ATT = -48 dB.
>

But snd_mixer_selem_get_playback_dB_range() does not return 48dB
**