Re: [PATCH 2/2] hwmon: ltc4296-1: add driver support

Re: [PATCH 2/2] hwmon: ltc4296-1: add driver support

[Guenter Roeck]

Hi,

On 10/25/24 04:56, Antoniu Miclaus wrote:
> Add support for LTC4296-1 is an IEEE 802.3cg-compliant,
> five port, single-pair power over Ethernet (SPoE), power
> sourcing equipment (PSE) controller.
> 
> Signed-off-by: Antoniu Miclaus <antoniu.miclaus@analog.com>
> ---

...

> +	hwmon_dev = devm_hwmon_device_register_with_groups(&spi->dev,
> +							   spi->modalias,
> +							   st, ltc4296_1_groups);

New drivers must use the the with_info() hardware monitoring API.

The API use is inappropriate: _enable attributes are supposed to enable
monitoring, not a power source. The hardware monitoring subsystem is
responsible for hardware _monitoring_, not control. It can be tied to
the regulator subsystem, but even that seems to be be inappropriate here.
I think the driver should probably reside in drivers/net/pse-pd/.
That doesn't mean it can not support hardware monitoring, but that
isn't really the chip's primary functionality.

Yes, I see that we already have ti,tps23861 in the hardware monitoring
subsystem, but that may be just as wrong.

I am copying the PSE subsystem maintainers and mailing list for advice.

Thanks,
Guenter

Re: [PATCH 2/2] hwmon: ltc4296-1: add driver support

[Oleksij Rempel]

Hi Guenter,

On Fri, Oct 25, 2024 at 07:22:08AM -0700, Guenter Roeck wrote:
> Hi,
> 
> On 10/25/24 04:56, Antoniu Miclaus wrote:
> > Add support for LTC4296-1 is an IEEE 802.3cg-compliant,
> > five port, single-pair power over Ethernet (SPoE), power
> > sourcing equipment (PSE) controller.
> > 
> > Signed-off-by: Antoniu Miclaus <antoniu.miclaus@analog.com>
> > ---
> 
> ...
> 
> > +	hwmon_dev = devm_hwmon_device_register_with_groups(&spi->dev,
> > +							   spi->modalias,
> > +							   st, ltc4296_1_groups);
> 
> New drivers must use the the with_info() hardware monitoring API.
> 
> The API use is inappropriate: _enable attributes are supposed to enable
> monitoring, not a power source. The hardware monitoring subsystem is
> responsible for hardware _monitoring_, not control. It can be tied to
> the regulator subsystem, but even that seems to be be inappropriate here.
> I think the driver should probably reside in drivers/net/pse-pd/.
> That doesn't mean it can not support hardware monitoring, but that
> isn't really the chip's primary functionality.
> 
> Yes, I see that we already have ti,tps23861 in the hardware monitoring
> subsystem, but that may be just as wrong.
> 
> I am copying the PSE subsystem maintainers and mailing list for advice.

Thank you! Yes, the PSE subsystem is the proper location for this chip.

Regards,
Oleksij
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