RE: [PATCH v2] regulator: ad5398: Fix min/max current limitboundary checking

[Axel Lin]

> >The equation to calculate the selector does not depend on max_uA.
> >So I think we don't need to set the requested max_uA.
> >
> 
> But, ad5398_set_current_limit() behaves different for min_uA and max_uA with you patch. Is this expected?
> 

What we want is to set the smallest current supported by this hardware
within the range you requested.

Current code uses below equation to choose selector:
selector = DIV_ROUND_UP((min_uA - chip->min_uA) * chip->current_level,
                        range_uA);

With this equation, we need to ensure min_uA >= chip->min_uA,
otherwise it returns a negative selector.

That is why we need to add:
if (min_uA < chip->min_uA)
        min_uA = chip->min_uA;


Axel

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