Re: [PATCH v3 2/2] arm64: dts: meson-gxbb: add support for

[Martin Blumenstingl <martin.blumenstingl@googlemail.com>]

On Sat, Nov 30, 2019 at 8:07 PM Mohammad Rasim
<mohammad.rasim96@gmail.com> wrote:
[...]
> > > > > +       leds {
> > > > > +               compatible = "gpio-leds";
> > > > > +               red {
> > > > > +                       label = "status";
> > > > this property seems to be deprecated now, see
> > > > Documentation/devicetree/bindings/leds/common.txt
> > > > but I'm not sure whether Kevin has made a decision yet when to not
> > > > accept "label" properties here anymore
> > > OK, I will remove the deprecated property
> > > but I'm not sure what should I choose as a function, LED_FUNCTION_STATUS
> > > or LED_FUNCTION_ACTIVITY ?
> > I haven't used function and color myself but I believe it works like
> > this (untested):
> > - add an #include <dt-bindings/leds/common.h> next to the other
> > #includes (keep alphabetical ordering). this include file also
> > contains all the #defines for color and function
> > - add a color property, for example: color = <LED_COLOR_ID_RED>;
> > - add a function property, for example: function = <LED_FUNCTION_STATUS>;
> > - test, debug and fix potential issues ;)
> Yes, I've already tested it but I'm just not sure what should be in the
> function property, LED_FUNCTION_STATUS and LED_FUNCTION_ACTIVITY both
> seem like good choices,
I haven't considered "activity" before, but most of our boards with
some kind of status LED use status in the label
unless someone objects: choose the one you like most

[...]
> if this property only used to lable the led then LED_FUNCTION_STATUS is
> ok, but maybe this is used by userspace to trigger the led ?!
in general devicetree describes hardware
I don't know if userspace does something "automatically" based on the
function. however, my expectation is that the trigger from
"linux,default-trigger" is used (if set) and that you can change the
trigger from userspace manually (if you wish)


Martin