linux-kernel - Re: [PATCH 2/4] hwmon: ina238: Add label support for voltage inputs

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <c7294130-5836-46c6-8d8b-e5d5a45f3d33@roeck-us.net>
Date: Thu, 17 Jul 2025 08:24:34 -0700
From: Guenter Roeck <linux@...ck-us.net>
To: Jonas Rebmann <jre@...gutronix.de>
Cc: Jean Delvare <jdelvare@...e.com>, Rob Herring <robh@...nel.org>,
	Krzysztof Kozlowski <krzk+dt@...nel.org>,
	Conor Dooley <conor+dt@...nel.org>, linux-hwmon@...r.kernel.org,
	linux-kernel@...r.kernel.org, Krzysztof Kozlowski <krzk@...nel.org>,
	devicetree@...r.kernel.org, kernel@...gutronix.de
Subject: Re: [PATCH 2/4] hwmon: ina238: Add label support for voltage inputs

On Thu, Jul 17, 2025 at 09:30:33AM +0200, Jonas Rebmann wrote:
> Hi Guenter,
> 
> Thanks for the review!
> 
> On 16/07/2025 17.04, Guenter Roeck wrote:
> > On 7/15/25 13:49, Jonas Rebmann wrote:
> > > The INA family of power monitors estimate power consumption based on
> > > two voltage measurements: across a shunt resistor and across the bus.
> > > 
> > > Conveniently label them "Shunt Voltage" and "Bus Voltage".
> > > 
> > 
> > Labels are supposed to show the sensor's association with the system, not
> > the chip labeling. So this is a no-go. And, yes, apparently I have been too
> > complacent with people (mis-)using the label attributes. That doesn't make
> > it better, so don't use it as argument to support this one.
> 
> As this chip measures power based on two voltage measurements, the
> measured voltage inputs must always be associated with the system in
> that way, that in1 measures the voltage on a bus and in0 over a shunt
> resistor on that bus.
> 
> Otherwise the Power/Energy/Charge-Measurements will be incorrect.
> 
> Do you have a suggestion on how to use the labels correctly or should I
> just drop the patch for v2?
> 
Please drop it.

Guenter

> Regards,
> Jonas
> 
> 
> -- 
> Pengutronix e.K.                          | Jonas Rebmann               |
> Steuerwalder Str. 21                      | http://www.pengutronix.de/  |
> 31137 Hildesheim, Germany                 | Phone: +49-5121-206917-0    |
> Amtsgericht Hildesheim, HRA 2686          | Fax:   +49-5121-206917-9    |
>