My main suggestion might be to figure out which light sensor the device is using, and then start googling from there.
Edit: here’s a KDE-related bash script that might give you some ideas for what you need, if it still works: Ambient Light Fix - KDE Store
(Unfortunately I don’t have KDE on any of my systems, I’m mostly a tiling VM kind of person, and have never bothered with ambient sensors so best I can do is offer these hints on starting points. But given this, that last bash-based solution seems like something up my alley for when I throw some BSD and BSPWM onto the Framework I’m waiting for. )
I don’t think that one is KDE specific, it is Intel specific. It does seem to mostly work.
It assigns a brightness variable from 1,000 to 100,000 to the brightness file.
*9,600 to 96,000
The ambient light sensor on the Framework seems to match 1:1 with the raw illuminance values, though the raw illuminance can detect values over 100% brightness.
A glitch in the script causes it to go full brightness in dark rooms, and when fixing the glitch it looks like the code was attempting to compensate for the monitor as a light source.
Edit:
This will need to be run as ‘sudo’. It works on Kubuntu 21.10.
#!/bin/bash
max=$(cat /sys/class/backlight/intel_backlight/max_brightness)
sensitivity=$((max/10))
min=$((max/10))
delay=6
while [ 1 ]
do
updated=1
while [ $updated -gt 0 ]
do
updated=0
backlight=$(cat /sys/class/backlight/intel_backlight/brightness)
sensor=$(cat /sys/bus/iio/devices/iio:device0/in_illuminance_raw)
target=$sensor
if [ $backlight -gt $sensor ]
then
if [ $(($backlight - $sensor)) -gt $sensitivity ]
then
updated=1
fi
fi
if [ $backlight -lt $sensor ]
then
if [ $(($backlight - $sensor)) -lt $sensitivity ]
then
updated=1
fi
fi
if [ $target -gt $max ]
then
target=$max
fi
if [ $target -lt 1 ]
then
target=$min
fi
if [ $updated -gt 0 ]
then
echo “Starting brightness: $backlight”
echo “Ambient light: $sensor”
echo “Adjusted brightness: $target”
echo “-------------------------------”
echo “Sensitivity: $sensitivity”
echo “Min: $min Max: $max”
echo
echo $target > /sys/class/backlight/intel_backlight/brightness
fi
done
sleep $delay
done
Hi. The ambient light sensor works by default on Fedora, but on Arch does not. Has anyone had a success with making the auto brightness regulation work in Arch? What type/model of ambient light sensor is used in Framework laptop by the way? I found nothing on ArchWiki about that, tried Autolight from AUR which also doesn’t work. Please advise.
Update. Fonund the solution that worked for me by running the bash script from that guy:
Upd2: The script launches but works kind of weird, seems not regulating the brightness in dependence with the ambient light.
Ok, finally made it work. Replaced the original AmbientLightFix_intel code with the provided by Monster_user above using vim. Thanks for that! Then ran sudo AmbientLightFix_RunME.sh and the screen brightness auto regulation has started working as a service even after reboot.
@Monster_user, do you know if there is a way to slow down the backlight transition rate?
Is there a command in the library to have a rate of change that is less abrupt?
Cheers
The ambient light sensor in that thinkpad and also the framework does work out of the box indeed on Gnome at least. Even back in 2017. I disabled it as quickly as I could because it’s annoying. Shadow of your head moves across the sensor? Brightness does down and up again. And not as smoothly as you might like.
peter@raamwerk ~> monitor-sensor
Waiting for iio-sensor-proxy to appear
+++ iio-sensor-proxy appeared
=== No accelerometer
=== Has ambient light sensor (value: 80,069000, unit: lux)
=== No proximity sensor
Light changed: 80,016000 (lux)
Light changed: 76,273000 (lux)
Light changed: 80,123000 (lux)
Light changed: 80,069000 (lux)
Light changed: 79,807000 (lux)
Light changed: 77,801000 (lux)
Light changed: 80,278000 (lux)
Light changed: 79,910000 (lux)
I assume monitor-sensor is a part of iio-sensor-proxy (which is not a gnome package and doesn’t have any gnome dependencies).
Which implies Gnome might be the only DE that supports ambient light sensors trough iio maybe? That line of text might also be outdated. If other desktops support it, then I expect that to just work if iio-sensor-proxy is installed. And even if your desktop doesn’t support it you could install it anyway so you can at least verify the sensor works with monitor-sensor.
Installing this package and rebooting has worked for me. Arch Linux, Gnome. I can put my hand over the sensor and the screen dims in steps. It would be great if it was smoother, but anything is better than nothing.
If you - like me - are working with a ddc-enabled external monitor most of the time you will find that brightnessctl does not detect these. If you want to have the brightness of such an external monitor automatically adjusted along with the internal one, you can use another shell script daemon that I uploaded for you just now. Enjoy!
Thanks for this script, works brilliantly. I had been looking for a way to get this working on my Arch install. Even been able to tweak the numbers to give me the brightness curve I want!
@Steel99xl Sorry for pinging you here, but I have a question about the auto brightness script you made via brightnessctl. Is there a way I can make it less sensitive? Your scripts seems like the ideal solution, but it just always results in setting the brightness to a much dimmer level than my environment. Maybe iio-proxy in interfering?
@Steel99xl Thanks! I adjusted that value and now its perfect for me! Just a suggestion, could you add a suggestion to your github page for this script that suggests that people adjust that value if they want a different outcome from this script?
/sys/bus/iio doesn’t exists in Ubuntu 22.04. Can some one tell how to activate this in Ubuntu 22.04? I have module_blacklist=hid_sensor_hub in my grub config file, to enable brightness keyboard switches.
I just found out that you can use systemd to run python scripts (via the same instructions from @Stike on May 25). So I wrote an auto-brightness script in python. This is my first python script ever! So bear with me; I got a little carried away and it may not be best coding practices, but it works flawlessly on my Framework 12th gen running Kubuntu 22.10.
#!/usr/bin/env python3
import os
import time
from math import copysign as cpsign
# Main Parameters
sensor_delay = 0.400
sensor_count = 5
brightness_adjust = +1.0
# Other Parameters for extra tweaking
min_brightness = 1
max_brightness = 96000
fps = 30
half_life_doubling_time = 600
threshold_ratio = 1.10
threshold_delta = 1000
min_change = int(1000/fps)
######################################
# Parameter Hints for Main parameters
# sensor_delay:
# - positive float
# - how often to take readings from sensor (in seconds)
# - recommended range: 0.1 - 3.0
# sensor_count
# - positive integer
# - number of measurements to average together from ambient light sensor
# - recommended range: 3 - 5 (use lower value for lower sensor_delay)
# brightness_adjust:
# - float
# - skews the screen brightness brighter (positive values) or dimmer (negative values) without affecting the min or max brightness
# - recommended range: -2.5 - +2.5
######################################
# Parameter Hints for Other parameters
# min_brightness:
# - integer
# - screen brightness will not go below this value; values less than one will cause the screen to reach 0% brightness before light sensor bottoms out
# - recommended range: -10,000 - 10,000
# max_brightness:
# - positive integer
# - numbers above 96,000 will cause the screen to reach 100% brightness before light sensor maxes out
# - recommended range: 60,000 - 120,000
# fps:
# - positive float
# - the "smoothness" of brightness change; when a change is brightness is triggered, this is the number of steps of intermediate brightness per second
# - recommended range: 5 - 45
# half_life_doubling_time:
# - positive integer
# - time (in milliseconds) to double or halve the current brightness, ie, rate of change
# - recommended range: 200 - 5000
# step_ratio:
# - float > 1.0
# - rate at which the screen brightness changes (per step). 1.01 is slow, 2+ is nearly instant
# - recommended range: 1.01 - 1.50 (can be smaller if steps value is high)
# threshold_ratio
# - float >= 1.0
# - minimum ratio of `target `to `current` before brightness change is triggered
# - recommended range: 1.0 -1.2
# threshold_delta:
# - non-negative integer
# - minimum difference between `target `and `current` before brightness changes
# - recommended range: 100 - 5000
# min_change:
# - positive integer
# - the minimum possible brightness change (per step). (set very high for instant change)
# - recommended range: 5 - 1000
#################################
# Function Definitions
echo = lambda str : os.system(f"echo {str}")
def getAmbientLight():
f = open("/sys/bus/iio/devices/iio:device0/in_illuminance_raw")
light = int(f.read())
f.close()
return light
def getScreenBrightness():
f = open("/sys/class/backlight/intel_backlight/brightness")
raw_bright = int(f.read())
f.close()
# return math.log(raw_bright/960, 10) * 50
return raw_bright
def light2bright(light):
percent = light / 3984
adjusted_percent = percent ** brightness_power
return round(adjusted_percent * (max_brightness - min_brightness) + min_brightness)
# initialize
brightness_power = 1 / (2**brightness_adjust)
steps = max(1, int(fps * sensor_delay))
step_ratio = 2 ** (1000/half_life_doubling_time/fps)
lights = [ getAmbientLight() ] * sensor_count
n = 0
# loop
while True:
n = (n+1) % sensor_count
l = getAmbientLight()
lights[n] = l
light_avg = sum(lights) / sensor_count
echo(f"light={l} and light_avg={light_avg}")
target = light2bright(light_avg)
current_bright = getScreenBrightness()
delta = target - current_bright
ratio = (target / current_bright) ** cpsign(1, delta)
echo(f"current_bright={current_bright} and target={target} so delta={delta} and ratio={ratio}")
if abs(delta) > threshold_delta \
or ratio > threshold_ratio:
for i in range(1, steps+1):
echo(f"' i={i}'")
b = current_bright * step_ratio ** cpsign(i, delta)
if abs(b - current_bright) < (i * min_change):
b = current_bright + cpsign(i*min_change, delta)
if (delta > 0 and b > target) or (delta < 0 and b < target):
os.system(f"brightnessctl -q s {target}")
echo(f"' set brightness to {target}'")
time.sleep((steps+1-i) * sensor_delay/steps)
break;
else:
os.system(f"brightnessctl -q s {round(b)}")
echo(f"' set brightness to {round(b)}'")
time.sleep(sensor_delay/steps)
else:
time.sleep(sensor_delay)
I made it highly tweakable for those who want more control over the sample rate, brightness curve, the rate and smoothness of transition, etc. Hope someone enjoys this!
)