Re: [PATCH 1/2] dt-bindings: iio: magnetometer: add QST QMC6308

["Siratul Islam" <siratul.islam@linux.dev>]

July 16, 2026 at 2:46 AM, "Jorijn van der Graaf" <jorijnvdgraaf@catcrafts.net mailto:jorijnvdgraaf@catcrafts.net?to=%22Jorijn%20van%20der%20Graaf%22%20%3Cjorijnvdgraaf%40catcrafts.net%3E > wrote:


> 
> Hi Siratul,
> 
> On Thu, 2026-07-16 at 00:32 +0600, Siratul Islam wrote:
> 
...
> 
> > 
> > I usually don't bother with bindings. But here I have some thoughts.
> >  You could reuse the QMC5883L binding. As for the device lacking both
> >  interrupt and vddio pins, you could exclude them like
> > 
> >  allOf:
> >  - if:
> >  properties:
> >  compatible:
> >  contains:
> >  const: qstcorp,qmc6308
> >  then:
> >  properties:
> >  interrupts: false
> >  vddio-supply: false
> > 
> >  But you would also need to remove the global required vddio-supply and
> >  make it required for qmc5883l.
> >  Or flip the logic of allOf. Considering a lot of the magnetometer
> >  bindings look very similar anyway, I'm not sure if it's worth
> >  combining them. Maybe Jonathan or DT maintainers would have a better
> >  opinion.
> > 
> I'd lean towards keeping the separate file.
Wait for more feedback before deciding, since you have a few days before 
you send v2. DT maintainers usually prefer reusing the same file where possible.
> The two schemas share only compatible/reg/vdd-supply: the QMC5883L has
> an interrupt pin and requires vddio-supply, while the QMC6308 (a 4-pin
> WLCSP) has neither. So a combined document would be mostly conditional
> machinery - the block you sketch plus a second one (or the flipped
> allOf you mention) for the required list. And as the two chips are not
> register-compatible, there is no fallback-compatible relationship to
> express either.
Register compatibility is driver specific. Bindings are only for describing hardware.
So if there are reasons to use separate bindings, this isn't one of them. A fallback-compatible 
relationship isn't needed, as we are already using an enum to list which different sensors
the binding supports.
> 
> Happy to fold it into qstcorp,qmc5883l.yaml in v2 if Jonathan or the
> DT maintainers prefer that shape.
> 
> Thanks,
> Jorijn
>
--
Best regards,
Sirat