[bisected]Blank laptop console after inactivity timeout

Boot to console (not X), after laptop screen goes blank due to inactivity, touch a key to get display back. Laptop backlight comes on but nothing is displayed. HDMI display comes back as it should.

git bisect says "first bad commit: [9127daa0a8d88a6e6452eb8b7c9be4c3f42a867e] drm/amd/display: Guard ASSR with internal display flag".

Previous commit is 6c8e1f3b95a2. I can "fix" the bug at 5.13-rc5 by

git diff 9127daa0a8d8 6c8e1f3b95a2|patch -p1

I have 3 AMD systems but only the laptop has the blank screen bug. It is an HP model 15-bw040AU, Product Id 1ZH49PA#ABG.

Bug originally logged at https://bugzilla.kernel.org/show_bug.cgi?id=213351