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Subject: Re: [PATCH v3 5/5] powernv:cpufreq: Implement the driver->get() method
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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On Fri, 2014-03-21 at 16:34 +0530, Gautham R Shenoy wrote:

> > >
> > > +/*
> > > + * Computes the current frequency on this cpu
> > > + * and stores the result in *ret_freq.
> > > + */
> > > +static void powernv_read_cpu_freq(void *ret_freq)
> > > +{
> > > +       unsigned long pmspr_val;
> > > +       s8 local_pstate_id;
> > > +       int *cur_freq, freq, pstate_id;
> > > +
> > > +       cur_freq = (int *)ret_freq;
> > 
> > You don't need cur_freq variable at all..
> 
> I don't like it either. But the compiler complains without this hack
> :-(

Casting integers into void * is a recipe for disaster... what is that
supposed to be about ? We lose all type checking and get exposed
to endian issues etc... the day somebody uses a different type on both
sides.

Also is "freq" a frequency ? In this case an int isn't big enough.

Cheers,
Ben.