Re: [PATCH 5/5] iio: adc: ad7606: add gain calibration support

[Angelo Dureghello]

On 30.04.2025 01:34, Andy Shevchenko wrote:
> On Tue, Apr 29, 2025 at 4:08 PM Angelo Dureghello
> <adureghello@xxxxxxxxxxxx> wrote:
> >
> > From: Angelo Dureghello <adureghello@xxxxxxxxxxxx>
> >
> > Add gain calibration support, using resistor values set on devicetree,
> > values to be set accordingly with ADC external RFilter, as explained in
> > the ad7606c-16 datasheet, rev0, page 37.
> >
> > Usage example in the fdt yaml documentation.
> 
> ...
> 
> > +#define AD7606_CALIB_GAIN_MIN  0
> > +#define AD7606_CALIB_GAIN_STEP 1024
> > +#define AD7606_CALIB_GAIN_MAX  65536
>
Hi Andy,
 
> Are those values in decimal in the datasheet?
> It looks to me something like
> 
> _MAX = (64 * _STEP)
> 
> but is it for real? Usually values are limited by the amount of bits
> in the HW, here it spans over 65 steps, i.e. 7 bits would be needed...
> Confusing.
>

true, thanks,
there must be a typo in the datasheet that says 0 to 65536 with a
step of 1024 with 6 bits. Only 0 to 63 are possbile here.

step 0 = 0
step 63 = 64512
 
Will fix that.

Regards,
angelo

> -- 
> With Best Regards,
> Andy Shevchenko