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

[Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>]

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@canonical.com>
>>>> ---
>>>>  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@suse.com>
>>>>    - Guenter Roeck <linux@roeck-us.net>
>>>>  
>>>> +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.


Best regards,
Krzysztof