Re: [PATCH v2] staging: iio: impedance-analyzer: ad5933: use div64_ul() instead of do_div()

[Jonathan Cameron]

On Mon, 23 Feb 2026 10:37:11 +0200
Andy Shevchenko <andriy.shevchenko@xxxxxxxxx> wrote:

> On Sun, Feb 22, 2026 at 01:43:26PM +0000, Jonathan Cameron wrote:
> > On Wed, 18 Feb 2026 15:51:14 +0200
> > Andy Shevchenko <andriy.shevchenko@xxxxxxxxx> wrote:  
> > > On Wed, Feb 18, 2026 at 06:23:27PM +0530, Archit Anant wrote:  
> > > > Replace do_div() with div64_ul() since the remainder is not used.
> > > > div64_ul() is the preferred API for 64-bit by 32-bit division when
> > > > only the quotient is needed.
> > > > 
> > > > Also replace explicit casting and shifting with the BIT_ULL(27) macro
> > > > for clarity.
> > > > 
> > > > Note: A mathematical simplification to `(freq * BIT_ULL(29)) / mclk` was
> > > > suggested during review to improve precision. However, as confirmed by
> > > > maintainers, the original driver's truncation via `(mclk / 4)` might
> > > > be intentional or relied upon by userspace. Since hardware is not
> > > > available for verification, this patch preserves the original logic
> > > > to avoid regression risk in the absence of testing.
> > > > 
> > > > Issue identified by coccicheck using do_div.cocci.    
> > >   
> > > > Changes in v2:
> > > > - Replaced explicit `(u64)(1 << 27)` with `BIT_ULL(27)` as suggested by Andy Shevchenko.
> > > > - Kept original arithmetic logic `(mclk / 4)` to preserve behavior.    
> > > 
> > > The place for changelog (and comments)...
> > >   
> > > > Signed-off-by: Archit Anant <architanant5@xxxxxxxxx>
> > > > ---    
> > > 
> > > ...is here.
> > > 
> > > But do not resend until maintainers explicitly ask for that.
> > >   
> > Tweaked commit message as Andy pointed out was needed.
> > 
> > Applied to the togreg branch of iio.git
> > 
> > Andy, if you want to give a tag I can role that in for now as need
> > to rebase anyway on rc1.  This mail felt like an 'almost tag' ;)  
> 
> I think you are talking about my Rb? Sure
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxx>
> 
Added. Thanks,