[U-Boot] [PATCH v6 1/4] EXYNOS5: Add gpio pin numbering feature

Simon Glass
2014-04-17T04:21:06Z

Hi Lukasz,

On 14 April 2014 23:25, Lukasz Majewski <l.majewski@samsung.com> wrote:

> Hi Simon,
>
> > Hi Lukasz,
> >
> > On 14 April 2014 01:17, Lukasz Majewski <l.majewski@samsung.com>
> > wrote:
> >
> > [snip[
> >
> > I think your questions are mostly answered but I wanted to chime in
> > on a few.
> >
> > What is wrong with specifying the bank field?
> > > Why your gpio command cannot use the bank approach?
> > >
> >
> > U-Boot has a generic GPIO API and we should try to use it where
> > possible. This has been a long-standing TODO for exynos.
>
> I'm also fully aware that Exynos suffers from inconsistent gpio API.
> However, I'm very glad that with Akshay's and our effort this goal
> will be accomplished :-)
>
> >
> >
> > >
> > > And one more question: Is this work compliant with new driver model,
> > > which will be accepted at the merge window after the v2014.04
> > > release?
> > >
> > > If not, then there is no point to review this code, since GPIO would
> > > need to be adjusted to use this framework.
> > >
> >
> > The driver model framework is already in mainline.
>
> I was rather thinking about the "big switch" as we did with KBUILD
> after the v2014.01. Anyway, I'm looking forward to see the wide
> deployment of device model in u-boot.
>

I don't expect a big switch. Each subsystem needs to add support for it,
and then (as a separate step) each driver needs to be ported into the new
uclass. So it will likely be an incremental effort.

> > At present only
> > sandbox uses it for GPIO. I started looking at exynos since I thought
> > it might be quite easy to convert, but found that the generic GPIO
> > stuff was still not merged.
> >
> > This series will make it much easier to convert exynos GPIO to driver
> > model, since we can just change the driver.
>
> Thanks for clarification.
>

I'm probably going to take a look at Tegra while waiting for this series to
land. Let's see how it goes.

Regards,
Simon