Fancontrol

vi /storage/.config/system.d/fancontrol.service

systemctl enable fancontrol

#!/bin/sh

# Summary
#
# Adjust fan speed by percentage when CPU/GPU is between user set
# Min and Max temperatures.
#
# Notes
#
# Temp can be gleaned from the sysfs termal_zone files and are in
# units millidegrees meaning a reading of 30000 is equal to 30.000 C
#
# Fan speed is read and controlled by he pwm_fan module and can be
# read and set from a sysfs file as well. The value can be set from 0 (off)
# to 255 (max). It defaults to 255 at start


## Set Points

# CPU Temp set points
MIN_TEMP=40 # Min desired CPU temp
MAX_TEMP=60 # Max desired CPU temp


# Fan Speeds set points
FAN_OFF=0       # Fan is off
FAN_MIN=38      # Some fans need a minimum of 15% to start from a dead stop.
FAN_MAX=255     # Max cycle for fan

# Frequency
CYCLE_FREQ=6            # How often should we check, in seconds
SHORT_CYCLE_PERCENT=20  # If we are shutting on or of more than this percent of the
                        # time, just run at min rather than shutting off

## Sensor and Control files

# CPU and GPU sysfs locations
CPU=/sys/class/thermal/thermal_zone0/temp
GPU=/sys/class/thermal/thermal_zone1/temp

# Fan Control files
FAN2=/sys/devices/platform/pwm-fan/hwmon/hwmon2/pwm1
FAN3=/sys/devices/platform/pwm-fan/hwmon/hwmon3/pwm1



## Logic

# The fan control file isn't available until the module loads and
# is unpredictable in path. Wait until it comes up

FAN=""
while [[ -z $FAN ]];do
        [[ -f $FAN2 ]] && FAN=$FAN2
        [[ -f $FAN3 ]] && FAN=$FAN3
        [[ -z $FAN ]] && sleep 1
done

# The sensors are in millidegrees so adjust the user
# set points to the same units

MIN_TEMP=$(( $MIN_TEMP * 1000 ))
MAX_TEMP=$(( $MAX_TEMP * 1000 ))


# Short cycle detection requires us to track the number
# of on-off flips to cycles

CYCLES=0
FLIPS=0

while true; do

        # Set TEMP to the highest GPU/CPU Temp
        TEMP=""
        read TEMP_CPU < $CPU
        read TEMP_GPU < $GPU
        [[ $TEMP_CPU -gt $TEMP_GPU ]] && TEMP=$TEMP_CPU || TEMP=$TEMP_GPU

        # How many degress above or below our min threshold are we?
        DEGREES=$(( $TEMP-$MIN_TEMP ))

        # What percent of the range between min and max is that?
        RANGE=$(( $MAX_TEMP-$MIN_TEMP ))
        PERCENT=$(( (100*$DEGREES/$RANGE) ))

        # What number between 0 and 255 is that percent?
        FAN_SPEED=$(( (255*$PERCENT)/100 ))

        # Override the calculated speed for some special cases
        if [[ $FAN_SPEED -le $FAN_OFF ]]; then                  # Set anything 0 or less to 0
                FAN_SPEED=$FAN_OFF
        elif [[ $FAN_SPEED -lt $FAN_MIN ]]; then                # Set anything below the min to min
                FAN_SPEED=$FAN_MIN
        elif [[ $FAN_SPEED -ge $FAN_MAX ]]; then                # Set anything above the max to max
                FAN_SPEED=$FAN_MAX
        fi

        # Did we just flip on or off?
        read -r OLD_FAN_SPEED < $FAN
        if (    ( [[ $OLD_FAN_SPEED -eq 0 ]] && [[ $FAN_SPEED -ne 0 ]] ) || \
                ( [[ $OLD_FAN_SPEED -ne 0 ]] && [[ $FAN_SPEED -eq 0 ]] ) ); then
                FLIPS=$((FLIPS+1))
        fi

        # Every 10 cycles, check to see if we are short-cycling
        CYCLES=$((CYCLES+1))
        if [[ $CYCLES -ge 10 ]] && [[ ! $SHORT_CYCLING ]]; then
                FLIP_PERCENT=$(( 100*$FLIPS/$CYCLES ))
                if [[ $FLIP_PERCENT -gt $SHORT_CYCLE_PERCENT ]]; then
                        SHORT_CYCLING=1
                        echo "Short-cycling detected. Fan will run at min speed rather than shutting off."
                else
                        CYCLES=0;FLIPS=0
                fi
        fi

        # If we are short-cycling and would turn the fan off, just set to min
        if [[ $SHORT_CYCLING ]] && [[ $FAN_SPEED -le $FAN_MIN ]]; then
                FAN_SPEED=$FAN_MIN
        fi

        # Every so often, exit short cycle mode to see if conditions have changed
        if [[ $SHORT_CYCLING ]] && [[ $CYCLES -gt 10000 ]]; then  # Roughly half a day
                echo "Exiting short-cycling"
                SHORT_CYCLING=""
        fi

        # Write that to the fan speed control file
        echo $FAN_SPEED > $FAN

        # Log the stats everyone once in a while
#       if [[ $LOG_CYCLES ]] && [[ $LOG_CYCLES -ge 10 ]]; then
#               echo "Temp was $TEMP fan set to $FAN_SPEED"
#               LOG_CYCLES=""
#       else
#               LOG_CYCLES=$(($LOG_CYCLES+1))
#       fi

        sleep $CYCLE_FREQ

done

# Also look at drive temps. The sysfs filesystem isn't useful for
# all drives on RockPro64 so use smartctl instead

#ls -1 /dev/sd? | xargs -n1 smartctl -A | egrep ^194 | awk '{print $4}'