#!/bin/sh
# /usr/sbin/temper - Thecus F75375 fan control script
#
# v1: From community n2100 fan control script (who is the author?)
# v2: Moved to a separate n1200 version
# v3: Hacked to work on both n1200 and n2100

# Fan controller
F75375=`find /sys -name 0-002e | grep i2c-0`
PWM1=$F75375/pwm1

# Chip temperature values, maximum allowed temp. and temp. log threshold
CHIPS=$F75375/temp?_input
TC_CRIT=70
TC_MAX=60
TC_THRESH=55

# Disk devices and maximum allowed temp. and temp. log threshold
DISKS=/dev/sd?
TD_CRIT=70
TD_MAX=60
TD_THRESH=55

# Fan device, lowest PWM value and control range
FAN=$F75375/pwm1
FAN_MIN=0
FAN_RNG=140

# Minimum temp
TMP_MIN=32

# Logging interval, in minutes. Keep this above the hard disk spin
# down time this will only log when above log thresholds(s)
LOG=1

# Enable the fan
echo 1 > $F75375/pwm1_enable

echo $$ > /var/run/temper.pid

while true ; do
i=0
while [ $i -lt $LOG ] ; do
   i=$(($i+1))
   # read the disk temperatures every minute
   TD=0
   for D in $DISKS ; do
      t=$(hddtemp -q -n $D)
      if [ $t -gt $TD ] ; then
         TD=$t
      fi
   done

   j=0
   while [ $j -lt 6 ] ; do
      j=$(($j+1))
      # read the chip temperatures every 10 seconds
      TC=0
      for C in $CHIPS ; do
         t=$(($(cat $C)/1000))
         if [ $t -gt $TC ] && [ $t -lt 255 ]; then
            TC=$t
         fi
      done

      FC=$(((($TC-$TMP_MIN)*$FAN_RNG)/($TC_MAX-$TMP_MIN)+$FAN_MIN))

      if [ $TC -gt $TC_MAX ] ; then
         FC=255
      elif [ $FC -gt $(($FAN_MIN+$FAN_RNG)) ] ; then
         FC=$FAN_MAX
      elif [ $FC -lt $FAN_MIN ] ; then
         FC=$FAN_MIN
      fi

      FD=$(((($TD-$TMP_MIN)*$FAN_RNG)/($TD_MAX-$TMP_MIN)+$FAN_MIN))

      if [ $TD -gt $TD_MAX ] ; then
         FD=255
      elif [ $FD -gt $(($FAN_MIN+$FAN_RNG)) ] ; then
         FD=$FAN_MAX
      elif [ $FD -lt $FAN_MIN ] ; then
         FD=$FAN_MIN
      fi

      if [ $FC -gt $FD ] ; then
         F=$FC
      else
         F=$FD
      fi

      if [ "$1" = "-m" ] ; then
         echo "chips $TC disks $TD -> fan $F"
         exit 0
      fi
      echo $F >$FAN
      # echo 0  >$PWM1

      sleep 10
   done

done

# If we are over our mid range tempterature thresholds log to syslog
if [ $TC -gt $TC_THRESH ] || [ $TD -gt $TD_THRESH ] ; then
   logger -p daemon.notice temper "- chips $TC, disks $TD -> fan $F"
fi

done

# EOF