activity-led usage
Yegor Yefremov
yegorslists at googlemail.com
Thu Oct 2 13:36:52 CEST 2025
Hi Heiko,
On Thu, Oct 2, 2025 at 1:30 PM Heiko Schocher <hs at nabladev.com> wrote:
>
> Hello Yegor,
>
> On 02.10.25 13:28, Yegor Yefremov wrote:
> > Hi Heiko,
> >
> > On Thu, Oct 2, 2025 at 10:26 AM Heiko Schocher <hs at nabladev.com> wrote:
> >>
> >> Hello Yegor,
> >>
> >> On 02.10.25 10:22, Yegor Yefremov wrote:
> >>> Hi Simon and Marek,
> >>>
> >>> On Wed, Oct 1, 2025 at 1:09 AM Simon Glass <sjg at chromium.org> wrote:
> >>>>
> >>>> Hi Yegor,
> >>>>
> >>>> On Tue, 30 Sept 2025 at 08:48, Yegor Yefremov
> >>>> <yegorslists at googlemail.com> wrote:
> >>>>>
> >>>>> Hi Simon,
> >>>>>
> >>>>> On Tue, Sep 30, 2025 at 4:13 PM Simon Glass <sjg at chromium.org> wrote:
> >>>>>>
> >>>>>> Hi Yegor,
> >>>>>>
> >>>>>> On Tue, 30 Sept 2025 at 06:35, Yegor Yefremov
> >>>>>> <yegorslists at googlemail.com> wrote:
> >>>>>>>
> >>>>>>> On Tue, Sep 30, 2025 at 12:29 PM Yegor Yefremov
> >>>>>>> <yegorslists at googlemail.com> wrote:
> >>>>>>>>
> >>>>>>>> Hi all,
> >>>>>>>>
> >>>>>>>> I added the following LED definition to the am335x-baltos.dts:
> >>>>>>>>
> >>>>>>>> leds {
> >>>>>>>> pinctrl-names = "default";
> >>>>>>>> pinctrl-0 = <&user_leds>;
> >>>>>>>>
> >>>>>>>> compatible = "gpio-leds";
> >>>>>>>>
> >>>>>>>> led-power {
> >>>>>>>> label = "led-red";
> >>>>>>>> gpios = <&gpio3 0 GPIO_ACTIVE_LOW>;
> >>>>>>>> default-state = "on";
> >>>>>>>> };
> >>>>>>>> };
> >>>>>>>> user_leds: user-leds-pins {
> >>>>>>>> pinctrl-single,pins = <
> >>>>>>>> AM33XX_PADCONF(AM335X_PIN_MII1_COL,
> >>>>>>>> PIN_OUTPUT_PULLDOWN, MUX_MODE7) /* mii1_col.gpio3_0 PWR LED */
> >>>>>>>> >;
> >>>>>>>> };
> >>>>>>>>
> >>>>>>>> The gpio-leds driver is working and I can toggle the led-red via the
> >>>>>>>> led command.
> >>>>>>>>
> >>>>>>>> Then, I created an am335x-baltos-u-boot.dtsi file with the following content:
> >>>>>>>>
> >>>>>>>> / {
> >>>>>>>> config {
> >>>>>>>> u-boot,activity-led = "led-red";
> >>>>>>>> };
> >>>>>>>> };
> >>>>>>>>
> >>>>>>>> I have also tried "led-power" instead of "led-red".
> >>>>>>>>
> >>>>>>>> In my final DTS files I have the following nodes:
> >>>>>>>>
> >>>>>>>> leds {
> >>>>>>>> pinctrl-names = "default";
> >>>>>>>> pinctrl-0 = <0x56>;
> >>>>>>>> compatible = "gpio-leds";
> >>>>>>>>
> >>>>>>>> led-power {
> >>>>>>>> label = "led-red";
> >>>>>>>> gpios = <0x57 0x00 0x01>;
> >>>>>>>> default-state = "on";
> >>>>>>>> };
> >>>>>>>> };
> >>>>>>>>
> >>>>>>>> config {
> >>>>>>>> u-boot,activity-led = "led-red";
> >>>>>>>> };
> >>>>>>>>
> >>>>>>>> U-Boot cannot find the activity-led node.
> >>>>>>>> ofnode_options_get_by_phandle("activity-led", &led_node); returns -22,
> >>>>>>>> because ofnode_path("/options/u-boot") fails.
> >>>>>>>>
> >>>>>>>> When driver debug is enabled, I also see the following messages:
> >>>>>>>>
> >>>>>>>> bind node config
> >>>>>>>> Device 'config' has no compatible string
> >>>>>>>>
> >>>>>>>> My am335x-baltos-u-boot.dtsi code is similar to what I could find in
> >>>>>>>> arch/arm/dts for the boot-led usage.
> >>>>>>>>
> >>>>>>>> Where should I debug further?
> >>>>>>
> >>>>>> It is a bit confusing as there is still 'legacy' LED stuff in the
> >>>>>> tree. For your problem I would suggest checking that the LED device is
> >>>>>> configured correctly.
> >>>>>>
> >>>>>> For sandbox in test.dts you can see:
> >>>>>>
> >>>>>> options {
> >>>>>> u-boot {
> >>>>>> compatible = "u-boot,config";
> >>>>>> boot-led = <&sandbox_led_green>;
> >>>>>> activity-led = <&sandbox_led_red>;
> >>>>>> ...
> >>>>>> };
> >>>>>> };
> >>>>>>
> >>>>>> Check that led_init() is being called in the LED uclass.
> >>>>>
> >>>>> It is working now using your suggestion. Thanks.
> >>>>>
> >>>>>>>
> >>>>>>> Should activity-led be also mentioned in doc/device-tree-bindings/config.txt?
> >>>>>>
> >>>>>> We should be using /options/u-boot for this[1]
> >>>>>
> >>>>> This means, everything that can be found via the following command
> >>>>> won't work and should be removed?
> >>>>>
> >>>>> grep -r --include='*.dts[i]' boot-led arch/arm/dts
> >>>>
> >>>> Yes. I did a series to remove the legacy LED stuff last year but it
> >>>> wasn't applied because people wanted me to do more, probably what you
> >>>> are looking at doing now :-)
> >>>
> >>> This would be great if this patch series could be merged. Marek has a
> >>> board (arch/arm/dts/stm32mp157a-dhcor-avenger96-u-boot.dtsi) that can
> >>> be reworked too.
> >>>
> >>> AFAIK, led_activity_blink() is used very seldom. For example, in
> >>> cmd/ubi.c it is only used for writing [1]. mmc is omitted completely.
> >>> Is this intentional or is this functionality just missing?
> >>>
> >>> [1] https://github.com/u-boot/u-boot/blob/master/cmd/ubi.c#L494
> >>
> >> The commit which introduced this says:
> >> """
> >> commit 990f726ce797c040adda6d1e1bc6a21bd2b28657
> >> Author: Christian Marangi <ansuelsmth at gmail.com>
> >> Date: Tue Oct 1 14:24:41 2024 +0200
> >>
> >> ubi: implement support for LED activity
> >>
> >> Implement support for LED activity. If the feature is enabled,
> >> make the defined ACTIVITY LED to signal ubi write operation.
> >>
> >> Signed-off-by: Christian Marangi <ansuelsmth at gmail.com>
> >> Reviewed-by: Simon Glass <sjg at chromium.org>
> >> """
> >>
> >> So, at that time it was intentional ... yes ... but I ask me, why
> >> we do not use this LED also on read operations...
> >
> > So, in other words, patches are welcome :-)
>
> From my side: Full Ack.
>
> May we should ask "Christian Marangi <ansuelsmth at gmail.com>"
> if there are some special reasons for only adding it to the write
> command.
I have just sent a patch and included Christian Marangi in CC.
Yegor
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