AXP813 ADC/Battery temperature sensor

[Jack Mitchell]

First off, thank you for getting the usb-power/ac-power/battery support
upstreamed recently.

I have a custom board with an AXP818 PMIC which is very similar to the
Cubietruck5 and has support for a managed battery. However the battery
does not require any temperature sensing. In the recently added ADC
support for the AXP813 the adc_en1_mask includes BIT(0) for register
0x82 which enables "TS pin input to ADC enable". As the TS pin in our
design is not connected this does not allow the battery to be charged as
the temperature is deemed out of spec. To enable the battery I must set
this bit to 0 in order to turn off the temperature sensing. My problem
is that I'm not sure where in the code I should be adding this, I
believe it is either in the ADC driver or in the battery driver, and
that a device-tree property should be added, possibly something along
the lines of "x-powers,ts-pin-enable" with it defaulting to enabled?

Any thoughts on the matter would be appreciated as I'd like to implement
this in an upstream acceptable manner.

Regards,
Jack.