Re: [PATCH] dt-bindings: input: touchscreen: edt-ft5x06: change reg property

[Heiko Stübner]

Am Freitag, 29. Mai 2020, 00:01:36 CEST schrieb Rob Herring:
> On Wed, May 20, 2020 at 08:41:59PM +0200, Heiko Stübner wrote:
> > Hi Dmitry,
> > 
> > Am Mittwoch, 20. Mai 2020, 19:13:24 CEST schrieb Dmitry Torokhov:
> > > Hi Johan,
> > > 
> > > On Wed, May 20, 2020 at 09:33:27AM +0200, Johan Jonker wrote:
> > > > A test with the command below gives this error:
> > > > 
> > > > arch/arm/boot/dts/rk3188-bqedison2qc.dt.yaml:
> > > > touchscreen@3e: reg:0:0: 56 was expected
> > > > 
> > > > The touchscreen chip on 'rk3188-bqedison2qc' and other BQ models
> > > > was shipped with different addresses then the binding currently allows.
> > > > Change the reg property that any address will pass.
> > > > 
> > > > make ARCH=arm dtbs_check
> > > > DT_SCHEMA_FILES=Documentation/devicetree/bindings/input/touchscreen/
> > > > edt-ft5x06.yaml
> > > > 
> > > > Signed-off-by: Johan Jonker <jbx6244@xxxxxxxxx>
> > > > ---
> > > >  Documentation/devicetree/bindings/input/touchscreen/edt-ft5x06.yaml | 2 +-
> > > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > > > 
> > > > diff --git a/Documentation/devicetree/bindings/input/touchscreen/edt-ft5x06.yaml b/Documentation/devicetree/bindings/input/touchscreen/edt-ft5x06.yaml
> > > > index 383d64a91..baa8e8f7e 100644
> > > > --- a/Documentation/devicetree/bindings/input/touchscreen/edt-ft5x06.yaml
> > > > +++ b/Documentation/devicetree/bindings/input/touchscreen/edt-ft5x06.yaml
> > > > @@ -42,7 +42,7 @@ properties:
> > > >        - focaltech,ft6236
> > > >  
> > > >    reg:
> > > > -    const: 0x38
> > > > +    maxItems: 1
> > > 
> > > Should we have a list of valid addresses instead of allowing any
> > > address? Controllers usually have only a couple of addresses that they
> > > support.
> > 
> > from what I've read, the fdt touchscreen controllers are just a generic
> > cpu with device-specific (or better panel-specific) firmware, which seems
> > to include the address as well - so it looks to be variable.
> > 
> > But of course that is only 2nd hand knowledge for me ;-)
> > 
> > 
> > But also, the i2c address is something you cannot really mess up,
> > either it is correct and your touchscreen works, or it isn't and and
> > adding entries to this list every time a new address variant pops up
> > feels clumsy.
> 
> Is that an Ack?

for the patch itself:
Acked-by: Heiko Stuebner <heiko@xxxxxxxxx>


> I'm fine either way. It's really only useful if there's a single 
> address because with a list it could still be wrong just as any other 
> data like an interrupt number could be wrong.
> 
> Rob
>