Given TW20241220 with kernel 6.12.6 and resuming after suspend, the display
brightness starts to increase until reaching its maximum value, and then
switches off (Thinkpad T14 with AMD Ryzen 7 PRO 4750U). Since kernel version
6.12.4 works fine, I suspect that this was introduced with 6.12.5 and is due to 

commit 99a02eab82515343d536796aa917dee50aec1551
Author: Alex Deucher <alexander.deucher@amd.com>
Date:   Mon Nov 25 13:59:09 2024 -0500

    drm/amdgpu: rework resume handling for display (v2)

    commit 73dae652dcac776296890da215ee7dec357a1032 upstream.

    Split resume into a 3rd step to handle displays when DCC is
    enabled on DCN 4.0.1.  Move display after the buffer funcs
    have been re-enabled so that the GPU will do the move and
    properly set the DCC metadata for DCN.

    v2: fix fence irq resume ordering