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Date:   Fri, 7 Jul 2023 16:06:24 +0100
From:   Mark Brown <broonie@kernel.org>
To:     Takashi Iwai <tiwai@suse.de>
Cc:     Srinivas Kandagatla <srinivas.kandagatla@linaro.org>,
        Johan Hovold <johan@kernel.org>, perex@perex.cz,
        tiwai@suse.com, lgirdwood@gmail.com, ckeepax@opensource.cirrus.com,
        kuninori.morimoto.gx@renesas.com, linux-kernel@vger.kernel.org,
        pierre-louis.bossart@linux.intel.com, alsa-devel@alsa-project.org
Subject: Re: [PATCH] ASoC: codecs: wcd938x: fix dB range for HPHL and HPHR
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On Fri, Jul 07, 2023 at 03:47:47PM +0200, Takashi Iwai wrote:
> Mark Brown wrote:

> > The ASoC generic control stuff supports inverting the value prior to
> > presentation to userspace so it's masked there (instead of writing the
> > number userspace sees to the register we subtract the number from the
> > maximum value and write that to the register), pulling that up further
> > to the ALSA core might be nice I guess?

> I believe yes.  Though, I'm still not sure how we can improve the
> mismatch of dB min/max.  The dB values of those inverted controls
> reflect the result of subtraction, no?

Yes, the dB scale presented to userspace is reversed relative to the
ordering in the registers.

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