Re: [PATCH v9 4/4] rtc: ds1307: add frequency_test_enable sysfs attribute to check tick on m41txx

[Giulio Benetti]

Hi Andy,

Il 18/07/2018 18:26, Andy Shevchenko ha scritto:
> On Wed, Jul 18, 2018 at 5:06 PM, Giulio Benetti
> <giulio.benetti@xxxxxxxxxxxxxxxx> wrote:
>
> > > > +       int ret;
> > > > +
> > > > +       ret = kstrtobool(buf, &freq_test_en);
> > > > +       if (ret == -EINVAL) {
>
> > > What kind of other error code you may expect and why they are not
> > > considered as no error?
>
> > According to documentation, kstrtobool can only fail with -EINVAL.
> > See:
> > https://elixir.bootlin.com/linux/v4.18-rc5/source/lib/kstrtox.c#L332
>
> That's correct. So, what do you want to show by explicitly mentioned
> an error code in the condition?

So you mean I should check for negative values instead of specific 
error, right?

Thanks

Giulio