Re: [PATCH v2] hwmon: Add thermal sensor driver for Surface Aggregator Module

[Maximilian Luz <luzmaximilian@gmail.com>]

On 8/7/24 9:50 PM, Guenter Roeck wrote:
> On 8/7/24 12:25, Maximilian Luz wrote:
>> On 8/7/24 2:32 AM, Guenter Roeck wrote:
>>> On 8/4/24 16:08, Maximilian Luz wrote:
>>
>> [...]
>>
>>>> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
>>>> index b60fe2e58ad6..70c6385f0ed6 100644
>>>> --- a/drivers/hwmon/Kconfig
>>>> +++ b/drivers/hwmon/Kconfig
>>>> @@ -2080,6 +2080,16 @@ config SENSORS_SURFACE_FAN
>>>>         Select M or Y here, if you want to be able to read the fan's speed.
>>>> +config SENSORS_SURFACE_TEMP
>>>> +    tristate "Microsoft Surface Thermal Sensor Driver"
>>>> +    depends on SURFACE_AGGREGATOR
>>>
>>> As the kernel test robot points out, this dependency is wrong.
>>> __ssam_device_driver_register() is only available
>>> if SURFACE_AGGREGATOR_BUS is enabled.
>>
>> Right, I should have spotted this before submission, sorry. This should
>> be
>>
>>    depends on SURFACE_AGGREGATOR
>>    depends on SURFACE_AGGREGATOR_BUS
>>
> 
> SURFACE_AGGREGATOR_BUS already depends on SURFACE_AGGREGATOR, so the extra
> dependency is not needed.

Unfortunately, SURFACE_AGGREGATOR_BUS is a bool and SURFACE_AGGREGATOR
tri-state, and the inference of whether SURFACE_AGGREGATOR needs to be
built in or not breaks because of that. Meaning we could have something
like

     SENSORS_SURFACE_TEMP=y      (tri-state, module)
     SURFACE_AGGREGATOR_BUS=y    (bool, optional-code-flag)
     SURFACE_AGGREGATOR=m        (tri-state, module)

because SURFACE_AGGREGATOR_BUS is fine with either m or y. But in
reality, SENSORS_SURFACE_TEMP=y would require SURFACE_AGGREGATOR=y.

Maybe there's a better way to solve this? I guess it should be possible
to convert SURFACE_AGGREGATOR_BUS into a tri-state (even though it's
really just a flag to build a certain part of code into
SURFACE_AGGREGATOR).

I think at this point we could also consider removing that flag entirely
and just build the bus support in unconditionally... but that discussion
is outside of the scope here.

>> I'll fix that for v3 and likely re-spin this weekend. Anything else I
>> should address for that?
>>
> 
> I didn't notice anything, but then I didn't try to build the code myself,
> or try to run checkpatch. My tools run checkpatch --strict, as necessary
> for hwmon submissions, so you might want to make sure that it passes.

Perfect, I already checked that. Thank you!

Best regards,
Max