On Mon, 25 Apr 2016 08:54:35 +0200
Hans de Goede <hdego...@redhat.com> wrote:

> Hi,
> 
> On 23-04-16 20:09, Prof. Dr. Gundolf Kiefer wrote:
> > I would like to pass this question upstream. As what I can see from the
> > code (arch/arm/dts/sun7i-a20-cubietruck.dts,
> > configs/Cubietruck_defconfig), something actually has happened towards
> > supporting GPIOs/LEDs for that board.
> >
> > Can somebody from the u-boot upstream team comment on this? Are LEDs
> > supported now on the Cubietruck? Is additional testing required?
> 
> The cubietruck leds are supported in the kernel. unxi u-boot does not
> have LED support for any boards.
> 
> And TBH I don't really see much use in LED support in u-boot.

The reason why I needed LED support in u-boot was to give the user a
sufficiently quick visible feedback when the device is switched on,
i.e. a software-controlled power-on indicator. If the LEDs can only be
controlled by the kernel, it may take seconds during which the user of
has no chance to see if the device actually has power or not. Perhaps
for the same reason, the legacy u-boot-sunxi fork
(http://linux-sunxi.org/) had LED support.

I personally feel that the possibility to switch on LEDs before the
kernel is booted is not just a useful, but an important feature. And I
would regret seeing it disappear when moving from the legacy sunxi fork
to mainline u-boot.

But, of course, it is up to the developers and package maintainers to
decide which features are intergrated and which are not. Feel free to
decide if the patch I provided can improve the package or not.

Regards,

Gundolf

> 
> Regards,
> 
> Hans
> 
> >
> > Regards,
> >
> > Gundolf Kiefer
> >
> >
> > On Sat, 16 Apr 2016 14:55:54 -0700
> > Vagrant Cascadian <vagr...@debian.org> wrote:
> >
> >> Control: tags 783846 moreinfo upstream
> >> Control: forwarded 783846 
> >> http://lists.denx.de/pipermail/u-boot/2015-May/214036.html
> >> Control: found 783846 2014.10+dfsg1-5
> >>
> >> On 2015-05-05, Vagrant Cascadian wrote:
> >>> On 2015-04-30, Prof. Dr. Gundolf Kiefer wrote:
> >>>> It seems that the support for the onboard leds is missing for
> >>>> sunxi-based boards even in the latest version (Debian unstable). IMHO
> >>>> LEDs are very helpful for headless systems.
> >>>
> >>> Thanks for the patches!
> >>>
> >>> If you could submit these patches to u-boot upstream, that would be
> >>> best; we're trying to minimize the patches that are not already included
> >>> upstream.
> >>
> >> It looks like you attempted to get these upstream, though it doesn't
> >> sound like they were accepted at the time. Is the bug still present in
> >> current versions of u-boot (2016.03+ in Debian)?
> >>
> >> Thanks!
> >>
> >> live well,
> >>    vagrant
> >




---------------------------------------------------------------
Prof. Dr. Gundolf Kiefer
Effiziente Eingebettete Systeme  -  Efficient Embedded Systems
Fakultät für Informatik          -  Faculty of Computer Science
Hochschule Augsburg - University of Applied Sciences
http://ees.hs-augsburg.de
---------------------------------------------------------------

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