From mboxrd@z Thu Jan  1 00:00:00 1970
From: Patrick Lai <plai@codeaurora.org>
Subject: Mixer control for signed gain value
Date: Wed, 22 Jun 2011 23:32:19 -0700
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Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>, lrg@ti.com
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Hi,

The CODEC I am working with takes byte-long gain value in two's 
complement form.
In soc-core.c, the closest functions I see are
  snd_soc_info_volsw_s8
snd_soc_get_volsw_s8
snd_soc_set_volsw_s8

These functions are coded to work with two integer values. For my
purpose, I suppose that I can always set 2nd integer input as zero.
However, would I still be able to set volume like
amixer sset "Codec Gain" 100 as percentage. If yes, how will amixer
know to put upper 8 bits of 16 bit gain in 2nd integer value element?

Thanks
Patrick


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