support for "power saving policy" property
Feature summary
Allow for the compositor to hint to thr driver that it should disable/enable some power saving strategies - like AMD's ABM - that can interfere for example with color accuracy and expose user facing settings in Gnome Settings.
How would you like it to work
With the implementation of ABM since Kernel 6.9, it will enter mode 3 when ppd is set to power saving. This will give content a "deep fried" look as it severely messes with contrast and brightness, sometimes effectively making text with already a non-ideal contrast to the background very difficult to read. In balanced mode, this seems to be only set to 1. As can be taken from this thread as an example, the common user isn't necessarily aware of this feature. And due to the severity of the effect, changes are being proposed to the Kernel to not default to such a high level when it's not needed. And while this is quite a polarizing feature, there should be an option for a user to enable it when they want, though it needs to make it clear what the effects are.
By default, it's questionable if ABM should be set to any level in any mode, but given clear communication, there should be an option to enable ABM depending on the power mode and also to set the level. Level 1 has only very little effect on content's visual accuracy, yet can save about 0.5 W, which is quite a nice deal on a mobile device given that it only has very little drawback. But if a user wishes to save even more battery. they may chose to, but need to be able to tell what causes the consequences.