| Message ID | 20230929103650.86074-3-jonathanh@nvidia.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | hwmon: ina3221: Add selective summation support | expand |
On Fri, 29 Sep 2023 11:36:48 +0100, Jon Hunter wrote: > The INA3221 has a critical alert pin that can be controlled by the > summation control function. This function adds the single > shunt-voltage conversions for the desired channels in order to > compare the combined sum to the programmed limit. The Shunt-Voltage > Sum Limit register contains the programmed value that is compared > to the value in the Shunt-Voltage Sum register in order to > determine if the total summed limit is exceeded. If the > shunt-voltage sum limit value is exceeded, the critical alert pin > pulls low. > > For the summation limit to have a meaningful value, it is necessary > to use the same shunt-resistor value on all included channels. Add a new > vendor specific property, 'ti,summation-disable', to allow specific > channels to be excluded from the summation control function if the shunt > resistor is different to other channels or the channel should not be > considered for triggering the critical alert pin. > > Note that the ina3221 has always supported summing the various input > channels and summation is enabled by default if the shunt-resistor > values are the same. This change simply provides a way to exclude > inputs from the summation. If this property is not populated, then the > functionality of the driver does not change. > > Signed-off-by: Jon Hunter <jonathanh@nvidia.com> > Signed-off-by: Ninad Malwade <nmalwade@nvidia.com> > --- > .../devicetree/bindings/hwmon/ti,ina3221.yaml | 19 +++++++++++++++++++ > 1 file changed, 19 insertions(+) > Reviewed-by: Rob Herring <robh@kernel.org>
On Fri, Sep 29, 2023 at 11:36:48AM +0100, Jon Hunter wrote: > The INA3221 has a critical alert pin that can be controlled by the > summation control function. This function adds the single > shunt-voltage conversions for the desired channels in order to > compare the combined sum to the programmed limit. The Shunt-Voltage > Sum Limit register contains the programmed value that is compared > to the value in the Shunt-Voltage Sum register in order to > determine if the total summed limit is exceeded. If the > shunt-voltage sum limit value is exceeded, the critical alert pin > pulls low. > > For the summation limit to have a meaningful value, it is necessary > to use the same shunt-resistor value on all included channels. Add a new > vendor specific property, 'ti,summation-disable', to allow specific > channels to be excluded from the summation control function if the shunt > resistor is different to other channels or the channel should not be > considered for triggering the critical alert pin. > > Note that the ina3221 has always supported summing the various input > channels and summation is enabled by default if the shunt-resistor > values are the same. This change simply provides a way to exclude > inputs from the summation. If this property is not populated, then the > functionality of the driver does not change. > > Signed-off-by: Jon Hunter <jonathanh@nvidia.com> > Signed-off-by: Ninad Malwade <nmalwade@nvidia.com> > Reviewed-by: Rob Herring <robh@kernel.org> Applied. Thanks, Guenter
diff --git a/Documentation/devicetree/bindings/hwmon/ti,ina3221.yaml b/Documentation/devicetree/bindings/hwmon/ti,ina3221.yaml index 0fd8ae5f6a22..5f10f1207d69 100644 --- a/Documentation/devicetree/bindings/hwmon/ti,ina3221.yaml +++ b/Documentation/devicetree/bindings/hwmon/ti,ina3221.yaml @@ -58,6 +58,25 @@ patternProperties: shunt-resistor-micro-ohms: description: shunt resistor value in micro-Ohm + ti,summation-disable: + description: | + The INA3221 has a critical alert pin that can be controlled by the + summation control function. This function adds the single + shunt-voltage conversions for the desired channels in order to + compare the combined sum to the programmed limit. The Shunt-Voltage + Sum Limit register contains the programmed value that is compared + to the value in the Shunt-Voltage Sum register in order to + determine if the total summed limit is exceeded. If the + shunt-voltage sum limit value is exceeded, the critical alert pin + is asserted. + + For the summation limit to have a meaningful value, it is necessary + to use the same shunt-resistor value on all enabled channels. If + this is not the case or if a channel should not be used for + triggering the critical alert pin, then this property can be used + exclude specific channels from the summation control function. + type: boolean + required: - reg