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Kernel driver max6639
=====================

Supported chips:
  * Maxim MAX6639
    Prefix: 'max6639'
    Addresses scanned: I2C 0x2c, 0x2e, 0x2f
    Datasheet: http://pdfserv.maxim-ic.com/en/ds/MAX6639.pdf

Authors:
    He Changqing <hechangqing@semptian.com>
    Roland Stigge <stigge@antcom.de>

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

This driver implements support for the Maxim MAX6639. This chip is a 2-channel
temperature monitor with dual PWM fan speed controller. It can monitor its own
temperature and one external diode-connected transistor or two external
diode-connected transistors.

The following device attributes are implemented via sysfs:

Attribute              R/W  Contents
----------------------------------------------------------------------------
temp1_input            R    Temperature channel 1 input (0..150 C)
temp2_input            R    Temperature channel 2 input (0..150 C)
temp1_fault            R    Temperature channel 1 diode fault
temp2_fault            R    Temperature channel 2 diode fault
temp1_max              RW   Set THERM temperature for input 1
                            (in C, see datasheet)
temp2_max              RW   Set THERM temperature for input 2
temp1_crit             RW   Set ALERT temperature for input 1
temp2_crit             RW   Set ALERT temperature for input 2
temp1_emergency        RW   Set OT temperature for input 1
                            (in C, see datasheet)
temp2_emergency        RW   Set OT temperature for input 2
pwm1                   RW   Fan 1 target duty cycle (0..255)
pwm2                   RW   Fan 2 target duty cycle (0..255)
fan1_input             R    TACH1 fan tachometer input (in RPM)
fan2_input             R    TACH2 fan tachometer input (in RPM)
fan1_fault             R    Fan 1 fault
fan2_fault             R    Fan 2 fault
temp1_max_alarm        R    Alarm on THERM temperature on channel 1
temp2_max_alarm        R    Alarm on THERM temperature on channel 2
temp1_crit_alarm       R    Alarm on ALERT temperature on channel 1
temp2_crit_alarm       R    Alarm on ALERT temperature on channel 2
temp1_emergency_alarm  R    Alarm on OT temperature on channel 1
temp2_emergency_alarm  R    Alarm on OT temperature on channel 2