Re: [PATCH] dt-bindings: leds: Mark label property as deprecated

[Marek Vasut]

On 11/30/22 20:26, Pavel Machek wrote:
> On Wed 2022-11-30 13:19:05, Rob Herring wrote:
> > On Fri, Nov 25, 2022 at 10:26:30PM +0100, Marek Vasut wrote:
> > > On 11/22/22 13:23, Pavel Machek wrote:
> > > > Hi!
> > >
> > > Hi,
> > >
> > > > > Mark the label property as deprecated as it is mentioned
> > > > > in the description.
> > > >
> > > > Lets do it the other way around. Functions (etc) don't really provide
> > > > good enough description of LED, and label is still needed.
> > >
> > > Can you please provide a clear explanation which property or approach is the
> > > correct one for new DTs ?
> > >
> > > So far, the documentation states that "label" is deprecated, and users
> > > should replace it with "function" and "color".
> >
> > 'function' is what activity/operation the LED is associated with. It is
> > a fixed set of strings which s/w may use. It is a replacement for
> > 'linux,default-trigger'.
> >
> > 'label' is what is printed next to the LED for a human to read. 'label'
> > can be anything and the OS shouldn't care what it is.
>
> Unfortunately, no.
>
> We use label as a path in /sys/class/leds. And it looks like integer
> "function" is not really adequate for describing what LED does. There
> are too many LEDs and not enough integers, and it is common to have
> same function ("activity") on multiple devices ("wifi", "mmc", "eth").

The Documentation/devicetree/bindings/leds/common.yaml schema indicates 
that function is a string, not an integer:

"
 32   function:
 33     description:
 34       LED function. Use one of the LED_FUNCTION_* prefixed definitions
 35       from the header include/dt-bindings/leds/common.h. If there is no
 36       matching LED_FUNCTION available, add a new one.
 37     $ref: /schemas/types.yaml#/definitions/string
"