Re: [PATCH 6/6] dt-bindings: hwmon: jedec,jc42: add nxp,se97b

[Guenter Roeck]

On 10/8/21 1:00 AM, Krzysztof Kozlowski wrote:
> On 24/09/2021 13:51, Guenter Roeck wrote:
> > On Fri, Sep 24, 2021 at 08:57:44AM +0200, Krzysztof Kozlowski wrote:
> > > On 23/09/2021 23:16, Rob Herring wrote:
> > > > On Mon, Sep 20, 2021 at 08:21:14PM +0200, Krzysztof Kozlowski wrote:
> > > > > Document bindings for NXP SE97B, a DDR memory module temperature sensor
> > > > > with integrated SPD and EEPROM via Atmel's AT24 interface.
> > > > >
> > > > > Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxx>
> > > > > ---
> > > > >   Documentation/devicetree/bindings/hwmon/jedec,jc42.yaml | 9 +++++++++
> > > > >   1 file changed, 9 insertions(+)
> > > > >
> > > > > diff --git a/Documentation/devicetree/bindings/hwmon/jedec,jc42.yaml b/Documentation/devicetree/bindings/hwmon/jedec,jc42.yaml
> > > > > index a7bb4e3a1c46..0e49b3901161 100644
> > > > > --- a/Documentation/devicetree/bindings/hwmon/jedec,jc42.yaml
> > > > > +++ b/Documentation/devicetree/bindings/hwmon/jedec,jc42.yaml
> > > > > @@ -10,6 +10,14 @@ maintainers:
> > > > >     - Jean Delvare <jdelvare@xxxxxxxx>
> > > > >     - Guenter Roeck <linux@xxxxxxxxxxxx>
> > > > >   
> > > > > +select:
> > > > > +  properties:
> > > > > +    compatible:
> > > > > +      const: jedec,jc-42.4-temp
> > > > > +
> > > > > +  required:
> > > > > +    - compatible
> > > > > +
> > > >
> > > > Is this supposed to be in the last patch? And why is it needed?
> > >
> > > Yes, this is here on purpose because of nxp,se97b which is sensor with
> > > at24-compatible EEPROM.
> > >
> > > arch/arm/boot/dts/at91-nattis-2-natte-2.dts:
> > > 169         temp@18 {
> > > 170                 compatible = "nxp,se97b", "jedec,jc-42.4-temp";
> > >
> > > 171                 reg = <0x18>;
> > > 172                 smbus-timeout-disable;
> > > 173         };
> > > 174
> > > 175         eeprom@50 {
> > > 176                 compatible = "nxp,se97b", "atmel,24c02";
> >
> > How would that be handled anyway ? Yes, the chip includes both a temperature
> > sensor and an eeprom, but this node should most definitely not instantiate as
> > temperature sensor.
>
> I am not sure if I understand the problem you are mentioning. You have
> two nods in DT, two different compatible sets and two difference
> devices. One eeprom and other one a temperature sensor.

I didn't realize that the driver is supposed to bind to "jedec,jc-42.4-temp"
and that "nxp,se97b" is really informational.

Sorry for the confusion.

Guenter