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Kernel Driver IBMPOWERNV
========================

Supported systems:
  * Any recent IBM P servers based on POWERNV platform

Author: Neelesh Gupta

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

This driver implements reading the platform sensors data like temperature/fan/
voltage/power for 'POWERNV' platform.

The driver uses the platform device infrastructure. It probes the device tree
for sensor devices during the __init phase and registers them with the 'hwmon'.
'hwmon' populates the 'sysfs' tree having attribute files, each for a given
sensor type and its attribute data.

All the nodes in the DT appear under "/ibm,opal/sensors" and each valid node in
the DT maps to an attribute file in 'sysfs'. The node exports unique 'sensor-id'
which the driver uses to make an OPAL call to the firmware.

Usage notes
-----------
The driver is built statically with the kernel by enabling the config
CONFIG_SENSORS_IBMPOWERNV. It can also be built as module 'ibmpowernv'.

Sysfs attributes
----------------

fanX_input		Measured RPM value.
fanX_min		Threshold RPM for alert generation.
fanX_fault		0: No fail condition
			1: Failing fan
tempX_input		Measured ambient temperature.
tempX_max		Threshold ambient temperature for alert generation.
inX_input		Measured power supply voltage
inX_fault		0: No fail condition.
			1: Failing power supply.
power1_input		System power consumption (microWatt)