[PATCH 06/35] mfd: ab8500-core: Sysfs chip id modification

Lee Jones lee.jones at linaro.org
Wed Feb 20 05:43:10 EST 2013


On Wed, 20 Feb 2013, Marcus Cooper wrote:

> On 20 February 2013 09:13, Lee Jones <lee.jones at linaro.org> wrote:
> > On Tue, 19 Feb 2013, Arnd Bergmann wrote:
> >
> >> On Friday 15 February 2013, Lee Jones wrote:
> >> >         struct ab8500 *ab8500;
> >> > +       int chip_id = -EINVAL;
> >> >
> >> >         ab8500 = dev_get_drvdata(dev);
> >> > -       return sprintf(buf, "%#x\n", ab8500 ? ab8500->chip_id : -EINVAL);
> >> > +       if(ab8500) {
> >> > +               chip_id = ab8500->chip_id;
> >> > +               if((is_ab8505(ab8500) || is_ab9540(ab8500)) && ab8500->version != 0xFF)
> >> > +                       chip_id = (ab8500->version << 8) | chip_id;
> >> > +       }
> >> > +       return sprintf(buf, "%#x\n", chip_id);
> >> >  }
> >>
> >> What's the use of printing "ffffffea" for unknown versions here?
> >
> > You mean instead of -EINVAL? No idea, Marcus?
> >
> Looks like I'm guilty of just making the minimal changes. Arnd is
> right though, getting ffffffea(-EINVAL) back is pretty useless.
> I'll have to check user land to see what is using this.

Yes, it would be useful to know how it's parsed.

Thanks Marcus.

> Maybe not
> printing and returning 0 should be the correct behaviour
> when an unknown version is found.

-- 
Lee Jones
Linaro ST-Ericsson Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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