Re: [PATCH] ASoC: codecs: wcd938x: fix dB range for HPHL and HPHR

[Srinivas Kandagatla]

On 07/07/2023 08:35, Johan Hovold wrote:
> On Wed, Jul 05, 2023 at 01:57:23PM +0100, Srinivas Kandagatla wrote:
> > dB range for HPHL and HPHR gains are from +6dB to -30dB in steps of
> > 1.5dB with register values range from 0 to 24.
> >
> > Current code maps these dB ranges incorrectly, fix them to allow proper
> > volume setting.
> >
> > Fixes: e8ba1e05bdc0("ASoC: codecs: wcd938x: add basic controls")
> > Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
> > ---
> >   sound/soc/codecs/wcd938x.c | 6 +++---
> >   1 file changed, 3 insertions(+), 3 deletions(-)
> >
> > diff --git a/sound/soc/codecs/wcd938x.c b/sound/soc/codecs/wcd938x.c
> > index faa15a5ed2c8..3a3360711f8f 100644
> > --- a/sound/soc/codecs/wcd938x.c
> > +++ b/sound/soc/codecs/wcd938x.c
> > @@ -210,7 +210,7 @@ struct wcd938x_priv {
> >   };
> >   
> >   static const SNDRV_CTL_TLVD_DECLARE_DB_MINMAX(ear_pa_gain, 600, -1800);
> > -static const SNDRV_CTL_TLVD_DECLARE_DB_MINMAX(line_gain, 600, -3000);
> > +static const DECLARE_TLV_DB_SCALE(line_gain, -3000, 150, -3000);
>
> This looks wrong, and indeed that forth argument appears to be a mute
> flag. I guess that one should have been 0 (false) here?

yes, this should be true instead of a mute dB value.

> Headphone output also appears to be way too loud by default with this
> patch (alone) applied. Perhaps it's just the default mixer settings need
> to be updated to match?
>
> It looks like you're inverting the scale above. Perhaps that's intended,

yes, the highest value corresponds to lowest dB which is why its inverted.

> but some more details in the commit message as to what was wrong and
> what you intended to do would have been good.

HPHR/HPHL Volume control is broken on this codec.
current UCM uses digital volume control for x13s which needs to be moved 
to Analog volume control.
I have this change https://termbin.com/mpp9 in UCM which I plan to send 
out once I test and fix other paths as well.

--srini
> Johan