Re: [PATCH 2/5] dt-bindings: firmware: svc: add hwmon property

["NG, TZE YEE" <tze.yee.ng@altera.com>]

On 22/6/2026 10:05 pm, Krzysztof Kozlowski wrote:
> On Fri, Jun 19, 2026 at 02:38:53AM -0700, tze.yee.ng@altera.com wrote:
>> From: Tze Yee Ng <tze.yee.ng@altera.com>
>>
>> Altera Stratix 10 SoCFPGA supports hardware monitor access through the
>> service layer mailbox. Add an optional hwmon child node to the service
>> layer binding so device trees can describe the hardware monitor.
>>
>> Signed-off-by: Nazim Amirul <muhammad.nazim.amirul.nazle.asmade@altera.com>
>> Signed-off-by: Tze Yee Ng <tze.yee.ng@altera.com>
>> ---
>>   .../devicetree/bindings/firmware/intel,stratix10-svc.yaml     | 4 ++++
>>   1 file changed, 4 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/firmware/intel,stratix10-svc.yaml b/Documentation/devicetree/bindings/firmware/intel,stratix10-svc.yaml
>> index b42cfa78b28b..86ffdb10132f 100644
>> --- a/Documentation/devicetree/bindings/firmware/intel,stratix10-svc.yaml
>> +++ b/Documentation/devicetree/bindings/firmware/intel,stratix10-svc.yaml
>> @@ -62,6 +62,10 @@ properties:
>>       $ref: /schemas/fpga/intel,stratix10-soc-fpga-mgr.yaml
>>       description: Optional child node for fpga manager to perform fabric configuration.
>>   
>> +  hwmon:
>> +    $ref: /schemas/hwmon/altr,stratix10-hwmon.yaml
> 
> So hwmon is completely fake wrapper over two other wrappers... If in
> doubts, please read slides from DTS101 presentations from OSS, including
> the chapter about Linux driver design.
> 
> Best regards,
> Krzysztof
> 

Hi Krzystof,

Thanks for review.
You pointed out that the hwmon DT binding was not appropriate because 
this is not a discrete hardware block with its own MMIO/IRQ resources. I 
agree with that assessment.

In v2, we will remove the hwmon device tree binding entirely:
- There is no compatible string for the hwmon driver.
- There is no hwmon child node under the service layer in DTS.
- stratix10-svc registers a socfpga-hwmon platform device when 
CONFIG_SENSORS_ALTERA_SOCFPGA_HWMON is enabled, similar to how it 
already registers stratix10-rsu.
- The hwmon driver binds by platform device name only.
- Sensor channels are selected from hardcoded tables based on the parent 
service layer of_node compatible (intel,stratix10-svc or intel,agilex-svc).

Thanks,
Tze Yee