Today I tested U-Boot 2016.09 on a Cubietruck running Debian Jessie. The GPIO interface is working fine now. For example, the command
gpio set PH20 switches on the orange LED, which solves my problem. Thank you for the help. Gundolf Kiefer On Sun, 1 May 2016 12:54:49 -0600 Simon Glass <s...@chromium.org> wrote: > 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 > > --------------------------------------------------------------- --------------------------------------------------------------- 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 ---------------------------------------------------------------
