Hi,

On 25 April 2016 at 03:18, Prof. Dr. Gundolf Kiefer
<gundolf.kie...@hs-augsburg.de> wrote:
> 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.

There is the LED_GPIO Kconfig option if you are using the normal
device tree binding for GPIOs. You can use led_get_by_label() to get
an LED by label. The fully API is in led.h.

Regards,
Simon

>
> 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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