Re: [PATCH v4 05/11] clk: Introduce clk-tps68470 driver

[Andy Shevchenko]

On Mon, Nov 1, 2021 at 12:27 PM Hans de Goede <hdegoede@xxxxxxxxxx> wrote:
> On 10/25/21 13:24, Andy Shevchenko wrote:
> > On Mon, Oct 25, 2021 at 12:42 PM Hans de Goede <hdegoede@xxxxxxxxxx> wrote:

...

> >> +       for (i = 0; i < ARRAY_SIZE(clk_freqs); i++) {
> >> +               diff = clk_freqs[i].freq - rate;
> >> +               if (diff == 0)
> >> +                       return i;
> >
> >> +               diff = abs(diff);
> >
> > This needs a comment why higher (lower) frequency is okay.
>
> This function is called in 2 places:
>
> 1. From tps68470_clk_round_rate(), where higher/lower clearly is ok,
> (see the function name) so no comment needed.
>
> 2. From tps68470_clk_set_rate() where it is NOT ok and this is
> enforced in the caller:
>
>         unsigned int idx = tps68470_clk_cfg_lookup(rate);
>
>         if (rate != clk_freqs[idx].freq)
>                 return -EINVAL;
>
> This is not easy to describe in a comment, while being obvious
> if someone looking at this actually looks at the callers.

Hmm... but try your best. :-)

While at it, recently I have learned about util_macros.h. Any use of it here?
Or amending it there and re-using it here?

> >> +               if (diff < best_diff) {
> >> +                       best_diff = diff;
> >> +                       best_idx = i;
> >> +               }
> >> +       }

-- 
With Best Regards,
Andy Shevchenko