i8kmon/i8kfan for Dell Precision desktop

i8kmon.py

#!/usr/bin/python3

import re, subprocess, time

# On my Dell Precision desktop, the `i8kmon` controls the fan level according to the ambient temperature, not the CPU temperature.
# Maybe the i8kutils only works for laptop? I don't know. Luckly, the `i8kfan` CAN control the motherboard fan and CPU fan.
# It's usage is `i8kfan - -`, the first number is for motherboard, the second for CPU. You should test the sequence first.

# What this scirpt do is simple: get temperatures from `sensors`, and change the fan levels with `i8kfan`.
# It's similar to the original TCL version i8kmon.

# I'd suggest to run it with `daemon`, in /etc/rc.local, add this:
# daemon --respawn --output=/tmp/i8kmon_py.log  -- python3 -u /usr/bin/i8kmon.py &


# CPU temperature threshold, level 1 and level 2
#  ------------ 50 -------------- 65 ----------
#  ---- 45 ------------ 55 ------------

# motherboard temperature threshold, level 1 and level 2
#  ------------ 43 -------------- 50 ----------
#  ---- 41 ------------ 45 ------------

# if temp is below L1_LOW, turn fan off.
# if temp is higher than L1_HIGH, turn fan on level 1, and last until temp drop to L1_LOW.
# same for L2.

CPU_L1_LOW  = 45
CPU_L1_HIGH = 50
CPU_L2_LOW  = 55
CPU_L2_HIGH = 65

BOARD_L1_LOW  = 41
BOARD_L1_HIGH = 43
BOARD_L2_LOW  = 45
BOARD_L2_HIGH = 50

CHECK_INTERVAL = 5
DEBUG = True

BOARD_L1_LAST = False
BOARD_L2_LAST = False
CPU_L1_LAST = False
CPU_L2_LAST = False


def log(Msg='none'):
    global DEBUG
    if DEBUG:
        print('-------->>>', time.strftime("%Y-%m-%d %H:%M:%S"), Msg, '<<<------------')


def get_temp():
    temp_cmd = 'sensors'
    try:
        temp_output = subprocess.check_output(temp_cmd, stderr=subprocess.STDOUT, shell=True, universal_newlines=True)
    except:
        log(temp_cmd + " error")
        return None
    
    temp_output = str(temp_output)
    log(temp_output)
    
    matchObj = re.match(r'.*Ambient:\s+\+(\d+).*CPU:\s+\+(\d+).*', temp_output, re.MULTILINE|re.DOTALL)
    
    if matchObj:
        AmbientTemp = matchObj.group(1)
        CPUTemp = matchObj.group(2)
        return (int(AmbientTemp), int(CPUTemp))
    else:
        return None
    

def set_fan(BoardLevel=2, CPULevel=2):
    i8kfan_cmd = ['i8kfan', str(BoardLevel), str(CPULevel)]
    log(i8kfan_cmd)
    try:
        subprocess.call(i8kfan_cmd)
    except Exception as e:
        log(e)
        return None
    else:
        return True
    

def get_level(AmbientTemp=50, CPUTemp=80):
    global BOARD_L1_LAST
    global BOARD_L2_LAST
    global CPU_L1_LAST
    global CPU_L2_LAST

    global CPU_L1_LOW 
    global CPU_L1_HIGH
    global CPU_L2_LOW 
    global CPU_L2_HIGH

    global BOARD_L1_LOW 
    global BOARD_L1_HIGH
    global BOARD_L2_LOW 
    global BOARD_L2_HIGH

    BoardLevel = 2
    CPULevel = 2

    # for motherboard, fan flag
    if AmbientTemp < BOARD_L1_LOW:
        BOARD_L1_LAST = False
    elif AmbientTemp > BOARD_L1_HIGH:
        BOARD_L1_LAST = True

    if AmbientTemp < BOARD_L2_LOW:
        BOARD_L2_LAST = False
    elif AmbientTemp > BOARD_L2_HIGH:
        BOARD_L2_LAST = True

    # for motherboard, fan level
    if AmbientTemp < BOARD_L1_LOW:
        BoardLevel = 0
    elif AmbientTemp < BOARD_L1_HIGH:
        if BOARD_L1_LAST == True:
            BoardLevel = 1
        else:
            BoardLevel = 0
    elif AmbientTemp < BOARD_L2_LOW:
        BoardLevel = 1
    elif AmbientTemp < BOARD_L2_HIGH:
        if BOARD_L2_LAST == True:
            BoardLevel = 2
        else:
            BoardLevel = 1
    else:
        BoardLevel = 2

    # for CPU, fan flag
    if CPUTemp < CPU_L1_LOW:
        CPU_L1_LAST = False
    elif CPUTemp > CPU_L1_HIGH:
        CPU_L1_LAST = True

    if CPUTemp < CPU_L2_LOW:
        CPU_L2_LAST = False
    elif CPUTemp > CPU_L2_HIGH:
        CPU_L2_LAST = True

    # for CPU, fan level
    if CPUTemp < CPU_L1_LOW:
        CPULevel = 0
    elif CPUTemp < CPU_L1_HIGH:
        if CPU_L1_LAST == True:
            CPULevel = 1
        else:
            CPULevel = 0
    elif CPUTemp < CPU_L2_LOW:
        CPULevel = 1
    elif CPUTemp < CPU_L2_HIGH:
        if CPU_L2_LAST == True:
            CPULevel = 2
        else:
            CPULevel = 1
    else:
        CPULevel = 2

    # if CPU is too hot, set two fans to level 2
    if CPULevel == 2:
        BoardLevel = 2

    return (BoardLevel, CPULevel)


LastLevel = (2, 2)
while True:
    time.sleep(CHECK_INTERVAL)

    AllTemp = get_temp()
    if AllTemp:
        (AmbientTemp, CPUTemp) = AllTemp
        AllLevel = get_level(AmbientTemp, CPUTemp)
        if AllLevel:
            (BoardLevel, CPULevel) = AllLevel
            if AllLevel != LastLevel:
                r1 = set_fan(BoardLevel, CPULevel)
                if not r1:
                    log('set fan error')
                    break
            else:
                log('fan level not change')
            LastLevel = AllLevel
        else:
            continue
    else:
        log('error get_temp()')
        continue