Subject: Re: External temperature sensor
To: Luke Mewburn <>
From: Michael <>
List: current-users
Date: 10/06/2005 21:06:14
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>   | There's some support for Analog Devices ADT7467 and ADM1030 in the
>   | tree. ( 'some support' as in sensors can be read via envsys,
>   | thresholds can be set via sysctl but there's no way to change
>   | things like hysteresis, temperature/rpm slope or the more complex
>   | innards of the ADT 7467 )
> Arguably the envsys(4) API could be used instead of sysctl(3) for
> setting stuff like thresholds on a sensor, if the envsys API was
> slightly extended.

Agreed, this belongs into envsys. Sysctl was just the easiest way to do
it and so far nobody protested.

> I have a proposal for an ENVSYS_STREDATA which would support this.
> E.g, set the min & max members of envsys_tre_data and use the
> proposed ENVSYS_STREDATA to frob it to define the threshold. =20
> We use a similar technique abusing the rpms field of envsys_basic_info
> and ENVSYS_STREINFO to reset a sensor's alarm.

This should be generic enough to control the inner workings of more
complex fan controllers too ( the ADT 7467 for instance ), like which
fan responds to which sensors, slope, hysteresis and so on. Not that
most people would ever (need to) touch this but since the controller is
programmable in this way the driver should export it somehow.

have fun

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