[alsa-devel] [PATCH 1/2] ASoC: wm8960: correct the min gain value of some PGA

[Charles Keepax]

On Thu, Sep 10, 2015 at 11:58:21AM +0100, Mark Brown wrote:
> On Thu, Sep 10, 2015 at 09:24:20AM +0100, Charles Keepax wrote:
> > On Thu, Sep 10, 2015 at 09:15:32AM +0800, Zidan Wang wrote:
> 
> > > > > +static const DECLARE_TLV_DB_SCALE(adc_tlv, -9750, 50, 1);
> > > > > +static const DECLARE_TLV_DB_SCALE(dac_tlv, -12750, 50, 1);
> 
> > > I think the min register value will corresponding to the min gain.
> > > So value 0 will also have a gain value, although it's for digital mute.
> 
> > > Refer to wm8962 codec driver, beep gain range is -90db~-6db, step in 6db,
> > > but it define the beep gain like below:
> > > static const DECLARE_TLV_DB_SCALE(beep_tlv, -9600, 600, 1);
> 
> > I might have to defer to Mark on this one then, if it is normal
> > to just use an additional gain value for mute in this type of
> > situation then it is ok with me. But it doesn't seem like that
> > would be a sensible thing, as you are asking for -97.5dB but
> > that is not what you are getting which doesn't seem like the
> > nicest interface.
> 
> The last value in the scale macro is a flag saying if the minimum value
> is mute - if it's set to 1 userspace should know this is what's going
> on.

Ah sorry my bad, thanks.

In that case:

Acked-by: Charles Keepax <ckeepax at opensource.wolfsonmicro.com>

Thanks,
Charles