Re: [PATCH 05/11] dt-bindings: thermal: k3-j72xx: elaborate on binding descriptions

From: Bryan Brattlof
Date: Wed Oct 12 2022 - 14:21:09 EST


On October 12, 2022 thus sayeth Krzysztof Kozlowski:
> On 11/10/2022 19:17, Bryan Brattlof wrote:
> > Elaborate on the function of this device node as well as some of the
> > properties that this node uses.
> >
> > Signed-off-by: Bryan Brattlof <bb@xxxxxx>
> > ---
> > .../bindings/thermal/ti,j72xx-thermal.yaml | 27 ++++++++++++++++++-
> > 1 file changed, 26 insertions(+), 1 deletion(-)
> >
> > diff --git a/Documentation/devicetree/bindings/thermal/ti,j72xx-thermal.yaml b/Documentation/devicetree/bindings/thermal/ti,j72xx-thermal.yaml
> > index c74f124ebfc00..0b6a6fa07a532 100644
> > --- a/Documentation/devicetree/bindings/thermal/ti,j72xx-thermal.yaml
> > +++ b/Documentation/devicetree/bindings/thermal/ti,j72xx-thermal.yaml
> > @@ -9,6 +9,24 @@ title: Texas Instruments J72XX VTM (DTS) binding
> > maintainers:
> > - Keerthy <j-keerthy@xxxxxx>
> >
> > +description: |
> > + The TI K3 family of SoCs typically have a Voltage & Thermal
> > + Management (VTM) device to control up to 8 temperature diode
> > + sensors to measure silicon junction temperatures from different
> > + hotspots of the chip as well as provide temperature, interrupt
> > + and alerting information.
> > +
> > + The VTM device will periodically enable these temperature sensors
> > + to make a temperature measurement and store the reported data
> > + allowing the sensors to stay in a reset state when not in use
> > + to maximize the sensor's life.
> > +
> > + This VTM driver will then use the following polynomial equation to
>
> "VTM driver" is some physical/electronic element called driver? Or Linux
> driver? If the latter, drop it and just describe the equation.

Yeah I was trying to talk about the Linux driver. I'll edit it to only
the equation.

>
> > + calculate the temperature from the value stored in the VTM device.
> > +
> > + Temp = (-9.2627e-12) * x^4 + (6.0373e-08) * x^3 + \
> > + (-1.7058e-04) * x^2 + (3.2512e-01) * x + (-4.9003e+01)
> > +
> > properties:
> > compatible:
> > enum:
> > @@ -19,9 +37,16 @@ properties:
> > items:
> > - description: VTM cfg1 register space
> > - description: VTM cfg2 register space
> > - - description: VTM efuse register space
> > + - description: |
> > + A software trimming method must be applied to some Jacinto
> > + devices to function properly. This eFuse region provides
> > + the information needed for these SoCs to report
> > + temperatures accurately.
> >
> > power-domains:
> > + description: |
> > + Should contain the phandle to a power management (PM) domain
> > + node and the device-id of this device.
>
> This is quite generic - why adding it?

This was really a "while I'm here" addition. But there is no need, I can
drop this

Thanks again Krzysztof
~Bryan