On Thu, Sep 21, 2023 at 02:08:16PM +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. You are adding this feature to the driver, but requiring a new property to disable it. So what happens with an existing user (old DT) and a kernel with the new feature? Rob