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Kernel driver wm831x-hwmon
==========================

Supported chips:
  * Wolfson Microelectronics WM831x PMICs

    Prefix: 'wm831x'

    Datasheet:

	- http://www.wolfsonmicro.com/products/WM8310
	- http://www.wolfsonmicro.com/products/WM8311
	- http://www.wolfsonmicro.com/products/WM8312

Authors: Mark Brown <broonie@opensource.wolfsonmicro.com>

Description
-----------

The WM831x series of PMICs include an AUXADC which can be used to
monitor a range of system operating parameters, including the voltages
of the major supplies within the system.  Currently the driver provides
reporting of all the input values but does not provide any alarms.

Voltage Monitoring
------------------

Voltages are sampled by a 12 bit ADC.  Voltages in millivolts are 1.465
times the ADC value.

Temperature Monitoring
----------------------

Temperatures are sampled by a 12 bit ADC.  Chip and battery temperatures
are available.  The chip temperature is calculated as:

	Degrees celsius = (512.18 - data) / 1.0983

while the battery temperature calculation will depend on the NTC
thermistor component.