Re: [PATCH v4 1/2] dt-bindings: iio: light: add as7343

[Chang Yu <marcus.yu.56@gmail.com>]

Hi Jonathan,

A quick comment inline.

On Sun, Sep 13, 2026 at 01:56:52AM +0100, Jonathan Cameron wrote:
> On Fri, 11 Sep 2026 18:39:11 -0700
> Chang Yu <marcus.yu.56@gmail.com> wrote:
> 
> > +    description:
> > +      The driver current for the external LED connected to the LDR pin.
> > +    minimum: 4000
> > +    maximum: 258000
> > +    multipleOf: 2000
> > +    default: 12000
> > +
> > +  sync-gpios:
> > +    description: |
> > +      Optional GPIO pin that can be used either as a synchronization input to
> > +      start/stop measurement or as an external start/stop signal for
> > +      synchronizing with the connected LED.
> 
> So the datasheet starts referring to using this for some level of sync
> but then only actually treats it as as a gpio (maybe I'm missing something).
> Any idea what that stuff about start/stop is talking about?
> 
> The only thing I can find about this is the device diagram in figure 13 that has the GPIO
> wired to the led driver and the automatic measurement engine.
> 
That's what I got from the datasheet as well. They don't describe how to
use the GPIO pin to perform synchronizations at all.

The adafruit arduino driver
(https://github.com/adafruit/Adafruit_AS7343/blob/main/Adafruit_AS7343.cpp)
is slightly more helpful - the GPIO in output mode signals when the
spectral measurement starts. Unfortunately no information about input
mode.

> > +    maxItems: 1
> > +
> > +required:
> > +  - compatible
> > +  - reg
> > +  - vdd-supply
> > +
> > +additionalProperties: false
> 
>