Brightness slider delay/lag

Distribution

Mint 21.3

Package version

6.0.4

Graphics hardware in use

Advanced Micro Devices, Inc. [AMD/ATI] Renoir

Frequency

Always

Bug description

Holding the brightness button on my laptop will cause the slider to get stuck at 100% or 0%. The longer I hold down either button, the longer it will be stuck. Holding the buttons also introduces a delay, making it so that the slider is moving without me touching the button. the only way for me right now to change the brightness is quick single presses to get to the brightness i want.

Steps to reproduce

1. hold the button to increase brightness, keep holding the button even when the brightness is at 100%
2. after holding it for a while, hold the decrease brightness button
3. the brightness is stuck at 100% for some time. letting go of the decrease brightness button before the slider starts going down, it will eventually go down without any button presses and then be stuck at 0%.
4. not touching any buttons after this fixes it being stuck but it will happen again when holding any brightness button

Expected behavior

1. hold the button to increase brightness, keep holding the button even when the brightness is at 100%
2. after holding it for a while, hold the decrease brightness button
3. the brightness immediately decreases
   the behavior of the brightness buttons should match the behavior of the volume buttons

Additional information

I checked different linux distributions with different desktop environments and the problem only arises when the cinnamon desktop is active.

Start by reproducing the hold-and-reverse brightness-button sequence on Cinnamon using the steps in the report, then compare it with the volume-button behavior. Trace the Cinnamon brightness-button handling and verify that holding at either limit does not queue delayed changes and that reversing direction responds immediately.