[RPi4, LE12.0.1] Autostart.sh with python script for fan control won't work

Nathan.OTN · September 22, 2024 at 11:04 AM

Hey everyone ! Hope you are well !

I am trying to have a fan control script working at startup. I have a Pi 4 with Libreelec 12.0.1 freshly installed with RPi tools addon. Fan is controlled by PWM on PIN 18.

The control script runs well when I use the command: python /storage/fan_control.py

Python

#! /usr/bin/env python3
import time
import signal
import sys
sys.path.append('/storage/.kodi/addons/virtual.rpi-tools/lib')
from gpiozero import PWMOutputDevice
import os

# Configuration
FAN_PIN = 18            # BCM pin used to drive PWM fan
WAIT_TIME = 2           # [s] Time to wait between each refresh
PWM_FREQ = 25           # [kHz] 25kHz for Noctua PWM control

# Configurable temperature and fan speed
MIN_TEMP = 42           # under this temp value fan is switched to the FAN_OFF speed
MAX_TEMP = 68           # over this temp value fan is switched to the FAN_MAX speed
FAN_LOW = 30            # lower side of the fan speed range during cooling
FAN_HIGH = 99           # higher side of the fan speed range during cooling
FAN_OFF = 20            # fan speed to set if the detected temp is below MIN_TEMP
FAN_MAX = 100           # fan speed to set if the detected temp is above MAX_TEMP

# Get CPU's temperature
def getCpuTemperature():
        with open('/sys/class/thermal/thermal_zone0/temp') as f:
                return float(f.read()) / 1000

def setFanSpeed(speed):
                pwm_fan.value = speed/100  # divide by 100 to get values from 0 to 1
                return()

# Handle fan speed
def handleFanSpeed():
        temp = float(getCpuTemperature())
        #print("cpu temp: {}".format(temp))
        # Turn off the fan if temperature is below MIN_TEMP
        if temp < MIN_TEMP:
                setFanSpeed(FAN_OFF)
                #print("Fan OFF") # Uncomment for testing
        # Set fan speed to MAXIMUM if the temperature is above MAX_TEMP
        elif temp > MAX_TEMP:
                setFanSpeed(FAN_MAX)
                print("Fan MAX") # Uncomment for testing
        # Caculate dynamic fan speed
        else:
                step = (FAN_HIGH - FAN_LOW)/(MAX_TEMP - MIN_TEMP)
                temp -= MIN_TEMP
                setFanSpeed(FAN_LOW + ( round(temp) * step ))
                #print(FAN_LOW + ( round(temp) * step )) # Uncomment for testing
        return ()


try:
                pwm_fan = PWMOutputDevice(FAN_PIN, initial_value=0,frequency=PWM_FREQ) # initialize FAN_PIN as a pwm out>
                setFanSpeed(FAN_OFF) # initially set fan speed to the FAN_OFF value
                while True:
                                handleFanSpeed() # call the function that calculates the target fan speed
                                time.sleep(WAIT_TIME) # wait for WAIT_TIME seconds before recalculate

except KeyboardInterrupt: # trap a CTRL+C keyboard interrupt
                setFanSpeed(FAN_HIGH)

#finally:
#    pwm_fan.close() # in case of unexpected exit, resets pin status (fan will go full speed after exiting)

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I have created an autostart.sh file and it also works (fan is controlled) when I execute sh /storage/.config/autostart.sh

When I boot the Raspberry, the fan is always running at full speed which means the python script isn't launched.

Here is the result of systemctl status kodi-autostart.service:

Code

● kodi-autostart.service - Kodi user autostart script
● kodi-autostart.service - Kodi user autostart script
     Loaded: loaded (/usr/lib/systemd/system/kodi-autostart.service; disabled; p
     Active: active (exited) since Tue 2024-02-27 17:26:17 UTC; 6 months 25 days
    Process: 865 ExecStart=/bin/sh -c . /etc/profile; test -f /storage/.config/a
   Main PID: 865 (code=exited, status=0/SUCCESS)
      Tasks: 0 (limit: 1590)
        CPU: 572ms
     CGroup: /system.slice/kodi-autostart.service

Sep 22 09:56:43 KodiPi sh[899]:            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Sep 22 09:56:43 KodiPi sh[899]:   File "/storage/.kodi/addons/virtual.rpi-tools/
Sep 22 09:56:43 KodiPi sh[899]:     self.pin.frequency = frequency
Sep 22 09:56:43 KodiPi sh[899]:     ^^^^^^^^^^^^^^^^^^
Sep 22 09:56:43 KodiPi sh[899]:   File "/storage/.kodi/addons/virtual.rpi-tools/
Sep 22 09:56:43 KodiPi sh[899]:     lambda self, value: self._set_frequency(valu
Sep 22 09:56:43 KodiPi sh[899]:                         ^^^^^^^^^^^^^^^^^^^^^^^^
Sep 22 09:56:43 KodiPi sh[899]:   File "/storage/.kodi/addons/virtual.rpi-tools/
Sep 22 09:56:43 KodiPi sh[899]:     raise PinPWMUnsupported(  # pragma: no cover
Sep 22 09:56:43 KodiPi sh[899]: gpiozero.exc.PinPWMUnsupported: PWM is not suppo

~
~
~
standard input lines 1-19/19 (END)
KodiPi:~ # clear
● kodi-autostart.service - Kodi user autostart script
● kodi-autostart.service - Kodi user autostart script
     Loaded: loaded (/usr/lib/systemd/system/kodi-autostart.service; disabled; preset: disabled)
     Active: active (exited) since Tue 2024-02-27 17:26:17 UTC; 6 months 25 days ago
    Process: 865 ExecStart=/bin/sh -c . /etc/profile; test -f /storage/.config/autostart.sh && exec /bin/sh /storage/.config/autostart
   Main PID: 865 (code=exited, status=0/SUCCESS)
      Tasks: 0 (limit: 1590)
        CPU: 572ms
     CGroup: /system.slice/kodi-autostart.service

Sep 22 09:56:43 KodiPi sh[899]:            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Sep 22 09:56:43 KodiPi sh[899]:   File "/storage/.kodi/addons/virtual.rpi-tools/lib/gpiozero/output_devices.py", line 396, in __init__
Sep 22 09:56:43 KodiPi sh[899]:     self.pin.frequency = frequency
Sep 22 09:56:43 KodiPi sh[899]:     ^^^^^^^^^^^^^^^^^^
Sep 22 09:56:43 KodiPi sh[899]:   File "/storage/.kodi/addons/virtual.rpi-tools/lib/gpiozero/pins/__init__.py", line 379, in <lambda>
Sep 22 09:56:43 KodiPi sh[899]:     lambda self, value: self._set_frequency(value),
Sep 22 09:56:43 KodiPi sh[899]:                         ^^^^^^^^^^^^^^^^^^^^^^^^^^
Sep 22 09:56:43 KodiPi sh[899]:   File "/storage/.kodi/addons/virtual.rpi-tools/lib/gpiozero/pins/__init__.py", line 374, in _set_freq
Sep 22 09:56:43 KodiPi sh[899]:     raise PinPWMUnsupported(  # pragma: no cover
Sep 22 09:56:43 KodiPi sh[899]: gpiozero.exc.PinPWMUnsupported: PWM is not supported on pin GPIO18

~
~
~
~
KodiPi:~ #

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I have tried to increase the sleep delay in autostart.sh to 60 and 120 but it does not make any difference.

Any idea ?

HarryH · September 22, 2024 at 6:46 PM

Please try this: Move the import line for os module upwards before you import from gpiozero and insert that line.

Python

import os
os.environ['LG_WD'] = '/tmp'
from gpiozero import PWMOutputDevice

LibreELEC 12 has been hardened. The lgpio module (used by gpiozero) needs a working directory path which isn't write protected: https://github.com/gpiozero/gpiozero/issues/1106

Nathan.OTN · September 22, 2024 at 8:25 PM

It works !!!! Thank you so much HarryH

For those who wants details, here is the content of fan_control.py:

Python

#! /usr/bin/env python3
import os
import time
import signal
import sys
sys.path.append('/storage/.kodi/addons/virtual.rpi-tools/lib')
os.environ['LG_WD'] = '/tmp'
from gpiozero import PWMOutputDevice


# Configuration
FAN_PIN = 18            # BCM pin used to drive PWM fan
WAIT_TIME = 2           # [s] Time to wait between each refresh
PWM_FREQ = 25           # [kHz] 25kHz for Noctua PWM control

# Configurable temperature and fan speed
MIN_TEMP = 42           # under this temp value fan is switched to the FAN_OFF speed
MAX_TEMP = 68           # over this temp value fan is switched to the FAN_MAX speed
FAN_LOW = 30            # lower side of the fan speed range during cooling
FAN_HIGH = 99           # higher side of the fan speed range during cooling
FAN_OFF = 20            # fan speed to set if the detected temp is below MIN_TEMP
FAN_MAX = 100           # fan speed to set if the detected temp is above MAX_TEMP

# Get CPU's temperature
def getCpuTemperature():
        with open('/sys/class/thermal/thermal_zone0/temp') as f:
                return float(f.read()) / 1000

def setFanSpeed(speed):
                pwm_fan.value = speed/100  # divide by 100 to get values from 0 to 1
                return()

# Handle fan speed
def handleFanSpeed():
        temp = float(getCpuTemperature())
        #print("cpu temp: {}".format(temp))
        # Turn off the fan if temperature is below MIN_TEMP
        if temp < MIN_TEMP:
                setFanSpeed(FAN_OFF)
                #print("Fan OFF") # Uncomment for testing
        # Set fan speed to MAXIMUM if the temperature is above MAX_TEMP
        elif temp > MAX_TEMP:
                setFanSpeed(FAN_MAX)
                print("Fan MAX") # Uncomment for testing
        # Caculate dynamic fan speed
        else:
                step = (FAN_HIGH - FAN_LOW)/(MAX_TEMP - MIN_TEMP)
                temp -= MIN_TEMP
                setFanSpeed(FAN_LOW + ( round(temp) * step ))
                #print(FAN_LOW + ( round(temp) * step )) # Uncomment for testing
        return ()


try:
                pwm_fan = PWMOutputDevice(FAN_PIN, initial_value=0,frequency=PWM_FREQ) # initialize FAN_PIN as a pwm output
                setFanSpeed(FAN_OFF) # initially set fan speed to the FAN_OFF value
                while True:
                                handleFanSpeed() # call the function that calculates the target fan speed
                                time.sleep(WAIT_TIME) # wait for WAIT_TIME seconds before recalculate

except KeyboardInterrupt: # trap a CTRL+C keyboard interrupt
                setFanSpeed(FAN_HIGH)

#finally:
#    pwm_fan.close() # in case of unexpected exit, resets pin status (fan will go full speed after exiting)

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Here is the content of autostart.sh:

Bash

#!/bin/bash
(
sleep 180
sh /storage/.config/fan_control.sh start
)&

Here is the content of fan_control.sh:

Code

#! /bin/sh

### BEGIN INIT INFO
# Provides:          fancontrol.py
# Required-Start:    $remote_fs $syslog
# Required-Stop:     $remote_fs $syslog
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
### END INIT INFO

# Carry out specific functions when asked to by the system
case "$1" in
  start)
    echo "Starting fancontrol.py"
    /storage/fan_control.py &
    ;;
  stop)
    echo "Stopping fancontrol.py"
    pkill -f /storage/fan_control.py
    ;;
  *)
    echo "Usage: /storage/.config/fan_control.sh {start|stop}"
    exit 1
    ;;
esac

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_PvD · October 6, 2024 at 4:36 PM

Hello all,

I have written a service addon that covers partial code from here. The idea behind the development of a service addon is that it is easy to use, no further scripts are required and it runs ootB. The addon is now part of the Kodinerds repo, the source code you'll find on github: https://github.com/b-jesch/service.joy-it.fancontrol. The addon is primary written for the Joy-IT Multimedia case but runs with other cases and integrated fans connected to GPIO17 too.

Anyway: While this service addon runs perfect in normal circumstances, it throws an exception when the addon is disabled and enabled again by the user in addon settings.

Why it's throwing "GPIO busy"? Normally all GPIO should be unlocked (closed) by gpiozero when the service finished - and it does so.

Code

2024-10-06 15:32:15.286 T:919     debug <general>: CAddonMgr: service.joy-it.fancontrol disabled
2024-10-06 15:32:15.350 T:1041    debug <general>: CServiceAddonManager: stopping service.joy-it.fancontrol.
2024-10-06 15:32:15.351 T:1041    debug <general>: CPythonInvoker(1, /storage/.kodi/addons/service.joy-it.fancontrol/fan.py): trigger Monitor abort request
2024-10-06 15:32:15.352 T:939      info <general>: [Joy-IT Fan Controller 1.0.9] Joy-IT fan control service finished
2024-10-06 15:32:15.352 T:939     debug <general>: CPythonInvoker(1, /storage/.kodi/addons/service.joy-it.fancontrol/fan.py): script successfully run
2024-10-06 15:32:15.352 T:939      info <general>: CPythonInvoker(1, /storage/.kodi/addons/service.joy-it.fancontrol/fan.py): waiting on thread 1496097344
2024-10-06 15:32:20.359 T:1041    error <general>: CPythonInvoker(1, /storage/.kodi/addons/service.joy-it.fancontrol/fan.py): script didn't stop in 5 seconds - let's kill it
2024-10-06 15:32:20.412 T:919     debug <general>: CGUIMediaWindow::GetDirectory (addons://user/xbmc.service)
2024-10-06 15:32:20.413 T:919     debug <general>:   ParentPath = [addons://user/xbmc.service]
2024-10-06 15:32:20.414 T:1049    debug <general>: Thread waiting start, auto delete: false
2024-10-06 15:32:20.420 T:1049    debug <general>: CAddonDatabase: SELECT repo.id FROM repo .. took 1 ms
2024-10-06 15:32:20.484 T:1049    debug <general>: CAddonDatabase: query  SELECT addons.*, repo.addonID AS repoID FROM addons JOIN addonlinkrepo ON addons.id=addonlinkrepo.idAddon JOIN repo ON repo.id=addonlinkrepo.idRepo WHERE addonlinkrepo.idRepo IN (1,2,3) ORDER BY repo.addonID, addons.addonID returned 1199 rows in 63 ms
2024-10-06 15:32:20.514 T:919     debug <general>: ------ Window Init (DialogBusy.xml) ------
2024-10-06 15:32:20.771 T:1049    debug <general>: CAddonDatabase::GetAddons took 350 ms
2024-10-06 15:32:20.804 T:1049    debug <general>: CAddonMgr::GetAddonsWithAvailableUpdate took 388 ms
2024-10-06 15:32:20.845 T:1049    debug <general>: Thread waiting 1371533888 terminating
2024-10-06 15:32:20.854 T:919     debug <general>: ------ Window Deinit (DialogBusy.xml) ------
2024-10-06 15:32:20.860 T:1050    debug <general>: Thread BackgroundLoader start, auto delete: false
2024-10-06 15:32:20.861 T:919     debug <general>: [threads] name: 'BackgroundLoader' priority: '1'
2024-10-06 15:32:20.863 T:1050    debug <general>: Thread BackgroundLoader 1454133824 terminating
2024-10-06 15:32:22.692 T:924     debug <general>: CLibInputKeyboard::ProcessKey - using delay: 500ms repeat: 33ms
2024-10-06 15:32:22.693 T:1051    debug <general>: Thread Timer start, auto delete: false
2024-10-06 15:32:22.694 T:919     debug <general>: Keyboard: scancode: 0x1c, sym: 0x0d, unicode: 0x0d, modifier: 0x0
2024-10-06 15:32:22.765 T:1051    debug <general>: Thread Timer 1603232320 terminating
2024-10-06 15:32:22.771 T:919     debug <general>: Keyboard: scancode: 0x1c, sym: 0x0d, unicode: 0x0d, modifier: 0x0
2024-10-06 15:32:22.771 T:919     debug <general>: HandleKey: return (0xf00d) pressed, window 10146, action is Select
2024-10-06 15:32:22.812 T:919     debug <general>: CAddonMgr: enabled service.joy-it.fancontrol
2024-10-06 15:32:22.813 T:1041    debug <general>: CServiceAddonManager: starting service.joy-it.fancontrol
2024-10-06 15:32:22.813 T:1053    debug <general>: Thread LanguageInvoker start, auto delete: false
2024-10-06 15:32:22.813 T:1053    debug <general>: initializing python engine.
2024-10-06 15:32:22.813 T:1053    debug <general>: CPythonInvoker(11, /storage/.kodi/addons/service.joy-it.fancontrol/fan.py): start processing
2024-10-06 15:32:22.862 T:919     debug <general>: CGUIMediaWindow::GetDirectory (addons://user/xbmc.service)
2024-10-06 15:32:22.862 T:919     debug <general>:   ParentPath = [addons://user/xbmc.service]
2024-10-06 15:32:22.863 T:1054    debug <general>: Thread waiting start, auto delete: false
2024-10-06 15:32:22.869 T:1054    debug <general>: CAddonDatabase: SELECT repo.id FROM repo .. took 1 ms
2024-10-06 15:32:22.887 T:1053    debug <general>: -->Python Interpreter Initialized<--
2024-10-06 15:32:22.887 T:1053    debug <general>:

2024-10-06 15:32:22.887 T:1053    debug <general>: CPythonInvoker(11, /storage/.kodi/addons/service.joy-it.fancontrol/fan.py): the source file to load is "/storage/.kodi/addons/service.joy-it.fancontrol/fan.py"
2024-10-06 15:32:22.919 T:1054    debug <general>: CAddonDatabase: query  SELECT addons.*, repo.addonID AS repoID FROM addons JOIN addonlinkrepo ON addons.id=addonlinkrepo.idAddon JOIN repo ON repo.id=addonlinkrepo.idRepo WHERE addonlinkrepo.idRepo IN (1,2,3) ORDER BY repo.addonID, addons.addonID returned 1199 rows in 49 ms
2024-10-06 15:32:22.963 T:919     debug <general>: ------ Window Init (DialogBusy.xml) ------
2024-10-06 15:32:23.203 T:1054    debug <general>: CAddonDatabase::GetAddons took 333 ms
2024-10-06 15:32:23.240 T:1054    debug <general>: CAddonMgr::GetAddonsWithAvailableUpdate took 374 ms
2024-10-06 15:32:23.280 T:1053    debug <general>: CPythonInvoker(11): full python path:
2024-10-06 15:32:23.280 T:1053    debug <general>: CPythonInvoker(11):   custom python path:
2024-10-06 15:32:23.280 T:1053    debug <general>: CPythonInvoker(11):     /storage/.kodi/addons/service.joy-it.fancontrol
2024-10-06 15:32:23.280 T:1053    debug <general>: CPythonInvoker(11):     /storage/.kodi/addons/virtual.rpi-tools/lib/
2024-10-06 15:32:23.280 T:1053    debug <general>: CPythonInvoker(11):   default python path:
2024-10-06 15:32:23.280 T:1053    debug <general>: CPythonInvoker(11):     /usr/lib/python311.zip
2024-10-06 15:32:23.280 T:1053    debug <general>: CPythonInvoker(11):     /usr/lib/python3.11
2024-10-06 15:32:23.280 T:1053    debug <general>: CPythonInvoker(11):     /usr/lib/python3.11/lib-dynload
2024-10-06 15:32:23.280 T:1053    debug <general>: CPythonInvoker(11):     /usr/lib/python3.11/site-packages
2024-10-06 15:32:23.280 T:1053    debug <general>: CPythonInvoker(11): adding args:
2024-10-06 15:32:23.280 T:1053    debug <general>: CPythonInvoker(11):
2024-10-06 15:32:23.281 T:1053    debug <general>: CPythonInvoker(11, /storage/.kodi/addons/service.joy-it.fancontrol/fan.py): entering source directory /storage/.kodi/addons/service.joy-it.fancontrol
2024-10-06 15:32:23.281 T:1054    debug <general>: Thread waiting 1371533888 terminating
2024-10-06 15:32:23.282 T:1053    debug <general>: CPythonInvoker(11, /storage/.kodi/addons/service.joy-it.fancontrol/fan.py): instantiating addon using automatically obtained id of "service.joy-it.fancontrol" dependent on version 3.0.0 of the xbmc.python api
2024-10-06 15:32:23.304 T:919     debug <general>: ------ Window Deinit (DialogBusy.xml) ------
2024-10-06 15:32:23.312 T:1055    debug <general>: Thread BackgroundLoader start, auto delete: false
2024-10-06 15:32:23.312 T:919     debug <general>: [threads] name: 'BackgroundLoader' priority: '1'
2024-10-06 15:32:23.316 T:1055    debug <general>: Thread BackgroundLoader 1454133824 terminating
2024-10-06 15:32:23.997 T:1053    debug <CAddonSettings[0@service.joy-it.fancontrol]>: trying to load setting definitions from old format...
2024-10-06 15:32:23.998 T:1053     info <general>: [Joy-IT Fan Controller 1.0.9] Joy-IT fan control service started
2024-10-06 15:32:24.043 T:1053    error <general>: EXCEPTION Thrown (PythonToCppException) : -->Python callback/script returned the following error<--
                                                    - NOTE: IGNORING THIS CAN LEAD TO MEMORY LEAKS!
                                                   Error Type: <class 'lgpio.error'>
                                                   Error Contents: 'GPIO busy'
                                                   Traceback (most recent call last):
                                                     File "/storage/.kodi/addons/virtual.rpi-tools/lib/gpiozero/pins/pi.py", line 411, in pin
                                                       pin = self.pins[info]
                                                             ~~~~~~~~~^^^^^^
                                                   KeyError: PinInfo(number=11, name='GPIO17', names=frozenset({'J8:11', 17, 'BOARD11', 'GPIO17', 'WPI0', '17', 'BCM17'}), pull='', row=6, col=1, interfaces=frozenset({'', 'gpio', 'spi', 'dpi', 'uart'}))

                                                   During handling of the above exception, another exception occurred:

                                                   Traceback (most recent call last):
                                                     File "/storage/.kodi/addons/service.joy-it.fancontrol/fan.py", line 36, in <module>
                                                       fan = PWMOutputDevice(int(addon.getSetting('gpio_pin')), initial_value=0, frequency=25) # PWM-Pin
                                                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
                                                     File "/storage/.kodi/addons/virtual.rpi-tools/lib/gpiozero/devices.py", line 108, in __call__
                                                       self = super().__call__(*args, **kwargs)
                                                              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
                                                     File "/storage/.kodi/addons/virtual.rpi-tools/lib/gpiozero/output_devices.py", line 392, in __init__
                                                       super().__init__(pin, active_high=active_high, initial_value=None,
                                                     File "/storage/.kodi/addons/virtual.rpi-tools/lib/gpiozero/output_devices.py", line 74, in __init__
                                                       super().__init__(pin, pin_factory=pin_factory)
                                                     File "/storage/.kodi/addons/virtual.rpi-tools/lib/gpiozero/mixins.py", line 75, in __init__
                                                       super().__init__(*args, **kwargs)
                                                     File "/storage/.kodi/addons/virtual.rpi-tools/lib/gpiozero/devices.py", line 553, in __init__
                                                       pin = self.pin_factory.pin(pin)
                                                             ^^^^^^^^^^^^^^^^^^^^^^^^^
                                                     File "/storage/.kodi/addons/virtual.rpi-tools/lib/gpiozero/pins/pi.py", line 413, in pin
                                                       pin = self.pin_class(self, info)
                                                             ^^^^^^^^^^^^^^^^^^^^^^^^^^
                                                     File "/storage/.kodi/addons/virtual.rpi-tools/lib/gpiozero/pins/lgpio.py", line 126, in __init__
                                                       lgpio.gpio_claim_input(
                                                     File "/storage/.kodi/addons/virtual.rpi-tools/lib/lgpio.py", line 755, in gpio_claim_input
                                                       return _u2i(_lgpio._gpio_claim_input(handle&0xffff, lFlags, gpio))
                                                              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
                                                     File "/storage/.kodi/addons/virtual.rpi-tools/lib/lgpio.py", line 458, in _u2i
                                                       raise error(error_text(v))
                                                   lgpio.error: 'GPIO busy'
                                                   -->End of Python script error report<--

2024-10-06 15:32:24.044 T:1053     info <general>: CPythonInvoker(11, /storage/.kodi/addons/service.joy-it.fancontrol/fan.py): waiting on thread 1371533888

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**mglae** · October 7, 2024 at 9:12 AM

Code

2024-10-06 15:32:15.351 T:1041    debug <general>: CPythonInvoker(1, /storage/.kodi/addons/service.joy-it.fancontrol/fan.py): trigger Monitor abort request
2024-10-06 15:32:15.352 T:939      info <general>: [Joy-IT Fan Controller 1.0.9] Joy-IT fan control service finished
2024-10-06 15:32:15.352 T:939     debug <general>: CPythonInvoker(1, /storage/.kodi/addons/service.joy-it.fancontrol/fan.py): script successfully run
2024-10-06 15:32:15.352 T:939      info <general>: CPythonInvoker(1, /storage/.kodi/addons/service.joy-it.fancontrol/fan.py): waiting on thread 1496097344
2024-10-06 15:32:20.359 T:1041    error <general>: CPythonInvoker(1, /storage/.kodi/addons/service.joy-it.fancontrol/fan.py): script didn't stop in 5 seconds - let's kill it

_PvD Guess without any knowledge about gpiozero: GPIO "resource" is not freed because thread is killed instead of terminated gracefully.

HarryH · October 7, 2024 at 8:43 PM

_PvD

this will not fix the cause, but you can prevent the problem by bypassing gpiozero and using lgpio directly.

lg library

PS: Your add-on project is currently not set to public.

_PvD · October 8, 2024 at 1:16 PM

Quote from HarryH

PS: Your add-on project is currently not set to public.

It's now public, thanks for the hint.

_PvD · October 8, 2024 at 7:08 PM

A new version of the service addon is using lgpio instead gpiozero. This avoids the 'GPIO busy' exception now. Thank you for pointing me in the right direction.

HopWorks · June 2, 2025 at 1:15 AM

Thank you Nathan for the code! Yes, this thread is old but considering what you did, and what I am trying to do, this is the freshest attempt I have seen after a whole day of researching.

Your code did not work for me. The fan just keeps running. But your nicely written code opened up a lot for me and I appreciate that! I am also using a Noctua Fan, a 5vdc PWM 40mm. To be honest, I am addicted to the Noctua line. I was able to control my fan just fine from the interactive python so I know I have everything hooked up correctly. But for some reason, using your code, the fan just stays on.

I have not gone after making the speed reporting line from the fan safe for RPI input yet. The specs say the interface works at 5vdc but is tolerant of 3.3vdc on the PWM line. But considering the speed reporting line will still throw 5vdc, I need to either place a level shifter on it, or at least a 3.3vdc zenier diode. Anyway, with that speed line, on maybe GPIO 23 or 24, or 4 maybe? I will be able to see the RPM's. Funny thing, this fan is REAL HARD to tell if it is at 1% or 100% speed without a completely quite room or putting my ear to it. lol

My only change is that I placed the fan_control.py in a subfolder of storage so it is at ~/scripts/fan_control.py and I updated any references I could find. I probably missed something.

When I boot, this is what my systemctl status kodi-autostart.service: shows...

Code

kodi-autostart.service - Kodi user autostart script
● kodi-autostart.service - Kodi user autostart script
     Loaded: loaded (/usr/lib/systemd/system/kodi-autostart.service; disabled; preset: disabled)
     Active: active (exited) since Sun 2025-06-01 19:17:24 EDT; 2min 54s ago
    Process: 778 ExecStart=/bin/sh -c . /etc/profile; test -f /storage/.config/autostart.sh && exec /bin/sh /storage/.config/autostart.sh (
   Main PID: 778 (code=exited, status=0/SUCCESS)
      Tasks: 2 (limit: 4915)
        CPU: 26ms
     CGroup: /system.slice/kodi-autostart.service
             ├─792 /bin/sh /storage/.config/autostart.sh
             └─794 sleep 180

Jun 01 19:17:24 HopMedia systemd[1]: Starting kodi-autostart.service...
Jun 01 19:17:24 HopMedia systemd[1]: Finished kodi-autostart.service.

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Thanks again for the great offering! I appreciate it!

HarryH · June 2, 2025 at 6:13 PM

Because it relies on gpiozero you could be affected by this (RPi gpiozero): https://libreelec.tv/2025/01/22/libreelec-nexus-12-0-2/

To find out where the problem comes from, what is the output of python3 /storage/scripts/fan_control.py ? Are there any exceptions/error messages? Or is this what you mean by?

Quote

I was able to control my fan just fine from the interactive python so I know I have everything hooked up correctly.

If this works, the next step should be to test the wrapper script:
sh /storage/scripts/fan_control.sh start and sh /storage/scripts/fan_control.sh stop

HopWorks · June 3, 2025 at 12:01 PM

Quote from HarryH

To find out where the problem comes from, what is the output of python3 /storage/scripts/fan_control.py ? Are there any exceptions/error messages? Or is this what you mean by?

The script works or at least it does not exit with any exceptions. I modified the temperature function slightly in order to output the current temp while running. When I said I was able to control my fan just fine, I meant at the most direct level. From the Python interactive environment, PWMOutputDevice(GPIO18, 25kHz), and changing the value of the resulting object by .01-1. I was actually surprised to see the fan spin at .01 but it IS a Noctua. My guess is the fan's controller has a floor limit for PWM duty cycle but without speed reporting, it's hard to test because the fan is so quite.

Code

def getCpuTemperature():
        with open('/sys/class/thermal/thermal_zone0/temp') as f:
                temp=float(f.read()) / 1000
                print(f"Current Temp - {temp}")
                return temp

#output
Current Temp - 36.998
Current Temp - 36.998
Current Temp - 37.485
Current Temp - 36.511
Current Temp - 36.998
Current Temp - 36.511
Current Temp - 36.511

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I will check the wrapper script next. Thank you for your help with this! I appreciate it.

HopWorks · June 3, 2025 at 12:58 PM

Quote from HarryH

If this works, the next step should be to test the wrapper script:
sh /storage/scripts/fan_control.sh start and sh /storage/scripts/fan_control.sh stop

I sorted it out. I had to set the execute flag on fan_control.py

Code

 # chmod +x fan_control.py

And the fan_control.sh is in /storage/.config/ by the way because that appears to be where the OP has it. I don't see that it matters so long as autostart.sh knows where it is. fan_control.sh works fine also and then I was greeted by my system temp every 2 seconds (ooops) so after careful timing of pasting sh /storage/.config/fan_control.sh stop and a quick press of ENTER and the temp reporting stopped. I went back in to fan_control.py and commented out my print statement, came back and did

sh /storage/.config/fan_control.sh start and it is working. At least the scripts are. Not sure about the fan speed yet. Now I just need to reboot and check for the process with htop.

Thanks HarryH!

HarryH · June 3, 2025 at 8:36 PM

You are welcome. It was just a guess on my part that you also moved the fan_control.sh shell script to the subfolder called ‘scripts’. You are right that it makes no difference where it is located as long as the path in the autostart.sh script matches.

If you set FAN_OFF = 0, the fan should be stopped until the CPU temp value cross the threshold of MIN_TEMP. So you could lower the value MIN_TEMP near to the idle temperature for testing purposes, to trigger ON/OFF earlier and check the functionality of the script.

HopWorks · June 4, 2025 at 12:56 AM

Quote from HarryH

You are welcome. It was just a guess on my part that you also moved the fan_control.sh shell script to the subfolder called ‘scripts’. You are right that it makes no difference where it is located as long as the path in the autostart.sh script matches.

If you set FAN_OFF = 0, the fan should be stopped until the CPU temp value cross the threshold of MIN_TEMP. So you could lower the value MIN_TEMP near to the idle temperature for testing purposes, to trigger ON/OFF earlier and check the functionality of the script.

Hey Harry, is there a document or guide out there that could take me through the intricacies of running background Python processes (autostart), how to include modules without PIP, how to write an addon (that accomplishes bringing in modules), how to bake in what I usually need, how to avoid using docker if possible, and the do's and don'ts of LibreElec?

It's VERY frustrating but I do not complain because I totally get why LibreElec is the way it is. I have had Kodi installed in an OS like Ubuntu, Raspbian, and have had amazing issues. Most of those were years ago, but that is because once I found LibreElec, I just haven't had reason to go back to my previous strategy for a few years.

But now I have progressed considerably with embedded systems, microcontrollers, hardware (and systems) design, and hungry to add interfaces with a core system. This adventure (this thread) about how to add an aftermarket PWM fan for cooling was just the surface. I want displays, IR, Radio control, power management, HEVC, etc. It's for me, not the public, but I learned today I need to know the inside-info about all of it in order to do it right.

I apologize if this info is already available and advertised. Just not sure where to look.

Thanks again!!!

HarryH · June 5, 2025 at 10:13 PM

Please keep in mind that LE is reduced to just the required components for KODI and hosted in a readonly root filesystem. All additional things (more than a simple script), which are not already available in the base image or as add-on, you want to install should be a package. This can be an add-on package or directly included in a self build image. Many things are documented in the Wiki, at GitHub and also in the code itself.

As for your example with the Python background process, you can set it up manually as you have already done, or create an KODI add-on (script or service) that does the same. Adding new additional Python libraries can be significantly more difficult and depends heavily on how experienced you already are with compiling and packaging Linux packages.
Maybe I'm just misunderstanding you. But your wishes/goals sound very ambitious and require a good understanding of hardware/specialised knowledge in some areas. There is no such thing as a simple all-in-one guide. You should also not ignore the fact that not everything can be realised or is necessary on every hardware platform.

Some starting points: