[U-Boot] Patch to enable LEDs on sunxi/Cubietruck

[U-Boot] Patch to enable LEDs on sunxi/Cubietruck

[Prof. Dr. Gundolf Kiefer]

Dear developers,

the attached patch adds LED support for the Cubietruck board.

I found that the support for the onboard leds is missing for
sunxi-based boards in the latest Debian unstable and perhaps
upstream version of U-Boot. IMHO LEDs are very helpful for headless
systems. Perhaps the patch can be helpful somehow.

The code has basically been ported from the U-Boot version maintained at
linux-sunxi.org. As in the sunxi version, the blue led is switched on
by default.

Kind regards,

Gundolf Kiefer



Begin forwarded message:

Date: Tue, 05 May 2015 09:46:39 -0700
From: Vagrant Cascadian <vagrant@aikidev.net>
To: "Prof. Dr. Gundolf Kiefer" <gundolf.kiefer@hs-augsburg.de>,
783846 at bugs.debian.org Subject: Re: Bug#783846: Patch to enable LEDs on
sunix/Cubietruck


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.


live well,
  vagrant



---------------------------------------------------------------
Prof. Dr. Gundolf Kiefer
Effiziente Eingebettete Systeme  -  Efficient Embedded Systems
Fakult?t f?r Informatik          -  Faculty of Computer Science
Hochschule Augsburg - University of Applied Sciences
http://www.hs-augsburg.de/~kiefer
---------------------------------------------------------------
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[U-Boot] Patch to enable LEDs on sunxi/Cubietruck

[Hans de Goede]

Hi,

On 05/12/2015 03:39 PM, Prof. Dr. Gundolf Kiefer wrote:
> Dear developers,
>
> the attached patch adds LED support for the Cubietruck board.
>
> I found that the support for the onboard leds is missing for
> sunxi-based boards in the latest Debian unstable and perhaps
> upstream version of U-Boot. IMHO LEDs are very helpful for headless
> systems. Perhaps the patch can be helpful somehow.
>
> The code has basically been ported from the U-Boot version maintained at
> linux-sunxi.org. As in the sunxi version, the blue led is switched on
> by default.
>
> Kind regards,
>
> Gundolf Kiefer

Thanks for the patch, but we really do not want to add new options to
CONFIG_SYS_EXTRA_OPTIONS, at a minimum you need to add new Kconfig
options for the leds, using gpio names for them, and sunxi_name_to_gpio
in some place to translate to gpio numbers.

But we really do not want that either for upstream u-boot master we've
switched to using devicetree for all sunxi boards, and we really want
to use devicetree for this, which already has the led info, rather then
duplicating the led info in sunxi defconfig files.

Simon, do we already have support for gpio-leds through devicetree
in the device-model code somewhere?

Regards,

Hans



>
>
> Begin forwarded message:
>
> Date: Tue, 05 May 2015 09:46:39 -0700
> From: Vagrant Cascadian <vagrant@aikidev.net>
> To: "Prof. Dr. Gundolf Kiefer" <gundolf.kiefer@hs-augsburg.de>,
> 783846 at bugs.debian.org Subject: Re: Bug#783846: Patch to enable LEDs on
> sunix/Cubietruck
>
>
> 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.
>
>
> live well,
>    vagrant
>
>
>
> ---------------------------------------------------------------
> Prof. Dr. Gundolf Kiefer
> Effiziente Eingebettete Systeme  -  Efficient Embedded Systems
> Fakult?t f?r Informatik          -  Faculty of Computer Science
> Hochschule Augsburg - University of Applied Sciences
> http://www.hs-augsburg.de/~kiefer
> ---------------------------------------------------------------
>

[U-Boot] Patch to enable LEDs on sunxi/Cubietruck

[Prof. Dr. Gundolf Kiefer]

Dear Hans,
dear developers,

thank you for the quick reply. Actually, this was the first time I ever
looked into the U-Boot code and I was (and am) not aware of the DT
support status in U-Boot. So, please apologize that using
CONFIG_SYS_EXTRA_OPTIONS is probably not the best solution.

Maybe, the following information is helpful to anybody working on it:

I am using Debian 8.0 (Jessie) with the stock kernel and U-Boot. The
stock kernel includes a devicetree blob supporting the LEDs on the
Cubietruck perfectly.

# dpkg -l |grep u-boot
ii  u-boot:armhf                      2014.10+dfsg1-5                   armhf        A boot loader for embedded systems
[...]
ii  u-boot-sunxi:armhf                2014.10+dfsg1-5gk1                armhf        A boot loader for sunxi systems
ii  u-boot-tools                      2014.10+dfsg1-5                   armhf        companion tools for Das U-Boot bootloader

# dpkg -l |grep linux-image
ii  linux-image-3.16.0-4-armmp-lpae   3.16.7-ckt9-3~deb8u1              armhf        Linux 3.16 for ARMv7 multiplatform compatible SoCs supporting LPAE
ii  linux-image-armmp-lpae            3.16+63                           armhf        Linux for ARMv7 multiplatform compatible SoCs supporting LPAE (meta-package)

# dpkg -L linux-image-3.16.0-4-armmp-lpae | grep truck
/usr/lib/linux-image-3.16.0-4-armmp-lpae/sun7i-a20-cubietruck.dtb

# ls -l /sys/devices/leds/leds/
total 0
drwxr-xr-x 3 root root 0 May 13 09:07 cubietruck:blue:usr/
drwxr-xr-x 3 root root 0 May 13 09:07 cubietruck:green:usr/
drwxr-xr-x 3 root root 0 May 13 10:01 cubietruck:orange:usr/
drwxr-xr-x 3 root root 0 May 13 09:06 cubietruck:white:usr/

Download link:
https://packages.debian.org/stable/kernel/linux-image-3.16.0-4-armmp-lpae

Regards,

Gundolf Kiefer


On Tue, 12 May 2015 17:15:26 +0200
Hans de Goede <hdegoede@redhat.com> wrote:

> Hi,
> 
> On 05/12/2015 03:39 PM, Prof. Dr. Gundolf Kiefer wrote:
> > Dear developers,
> >
> > the attached patch adds LED support for the Cubietruck board.
> >
> > I found that the support for the onboard leds is missing for
> > sunxi-based boards in the latest Debian unstable and perhaps
> > upstream version of U-Boot. IMHO LEDs are very helpful for headless
> > systems. Perhaps the patch can be helpful somehow.
> >
> > The code has basically been ported from the U-Boot version maintained at
> > linux-sunxi.org. As in the sunxi version, the blue led is switched on
> > by default.
> >
> > Kind regards,
> >
> > Gundolf Kiefer
> 
> Thanks for the patch, but we really do not want to add new options to
> CONFIG_SYS_EXTRA_OPTIONS, at a minimum you need to add new Kconfig
> options for the leds, using gpio names for them, and sunxi_name_to_gpio
> in some place to translate to gpio numbers.
> 
> But we really do not want that either for upstream u-boot master we've
> switched to using devicetree for all sunxi boards, and we really want
> to use devicetree for this, which already has the led info, rather then
> duplicating the led info in sunxi defconfig files.
> 
> Simon, do we already have support for gpio-leds through devicetree
> in the device-model code somewhere?
> 
> Regards,
> 
> Hans
> 
> 
> 
> >
> >
> > Begin forwarded message:
> >
> > Date: Tue, 05 May 2015 09:46:39 -0700
> > From: Vagrant Cascadian <vagrant@aikidev.net>
> > To: "Prof. Dr. Gundolf Kiefer" <gundolf.kiefer@hs-augsburg.de>,
> > 783846 at bugs.debian.org Subject: Re: Bug#783846: Patch to enable LEDs on
> > sunix/Cubietruck
> >
> >
> > 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.
> >
> >
> > live well,
> >    vagrant
> >
> >
> >
> > ---------------------------------------------------------------
> > Prof. Dr. Gundolf Kiefer
> > Effiziente Eingebettete Systeme  -  Efficient Embedded Systems
> > Fakult?t f?r Informatik          -  Faculty of Computer Science
> > Hochschule Augsburg - University of Applied Sciences
> > http://www.hs-augsburg.de/~kiefer
> > ---------------------------------------------------------------
> >




---------------------------------------------------------------
Prof. Dr. Gundolf Kiefer
Effiziente Eingebettete Systeme  -  Efficient Embedded Systems
Fakult?t f?r Informatik          -  Faculty of Computer Science
Hochschule Augsburg - University of Applied Sciences
http://www.hs-augsburg.de/~kiefer
---------------------------------------------------------------

[U-Boot] Patch to enable LEDs on sunxi/Cubietruck

[Simon Glass]

Hi Hans,

On 12 May 2015 at 09:15, Hans de Goede <hdegoede@redhat.com> wrote:
> Hi,
>
> On 05/12/2015 03:39 PM, Prof. Dr. Gundolf Kiefer wrote:
>>
>> Dear developers,
>>
>> the attached patch adds LED support for the Cubietruck board.
>>
>> I found that the support for the onboard leds is missing for
>> sunxi-based boards in the latest Debian unstable and perhaps
>> upstream version of U-Boot. IMHO LEDs are very helpful for headless
>> systems. Perhaps the patch can be helpful somehow.
>>
>> The code has basically been ported from the U-Boot version maintained at
>> linux-sunxi.org. As in the sunxi version, the blue led is switched on
>> by default.
>>
>> Kind regards,
>>
>> Gundolf Kiefer
>
>
> Thanks for the patch, but we really do not want to add new options to
> CONFIG_SYS_EXTRA_OPTIONS, at a minimum you need to add new Kconfig
> options for the leds, using gpio names for them, and sunxi_name_to_gpio
> in some place to translate to gpio numbers.
>
> But we really do not want that either for upstream u-boot master we've
> switched to using devicetree for all sunxi boards, and we really want
> to use devicetree for this, which already has the led info, rather then
> duplicating the led info in sunxi defconfig files.
>
> Simon, do we already have support for gpio-leds through devicetree
> in the device-model code somewhere?

No there is no driver at present. But given that we have
gpio_request_by_name() this should be pretty simple to implement (i.e.
the GPIO binding is already supported). I'm happy to help with
pointers/advice if you like.

Regards,
Simon

>
> Regards,
>
> Hans
>
>
>
>
>>
>>
>> Begin forwarded message:
>>
>> Date: Tue, 05 May 2015 09:46:39 -0700
>> From: Vagrant Cascadian <vagrant@aikidev.net>
>> To: "Prof. Dr. Gundolf Kiefer" <gundolf.kiefer@hs-augsburg.de>,
>> 783846 at bugs.debian.org Subject: Re: Bug#783846: Patch to enable LEDs on
>> sunix/Cubietruck
>>
>>
>> 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.
>>
>>
>> live well,
>>    vagrant
>>
>>
>>
>> ---------------------------------------------------------------
>> Prof. Dr. Gundolf Kiefer
>> Effiziente Eingebettete Systeme  -  Efficient Embedded Systems
>> Fakult?t f?r Informatik          -  Faculty of Computer Science
>> Hochschule Augsburg - University of Applied Sciences
>> http://www.hs-augsburg.de/~kiefer
>> ---------------------------------------------------------------
>>
>