Lenovo L14/L15/P14s Gen2 fails to resume from s0ix

S0ix resume is flaky on my Lenovo ThinkPad P14s Gen2.

Kernel: v5.14.10 + patches from #1721 (comment 1077338)

Problems:

1. It enters suspend just fine (breathing effect on lid/power button led). Neither pressing a key nor the power button wakes the machine from suspend. Opening the lid while suspended does trigger a very short spinup of the fan, but fails to wake. A USB keyboard does wake it from suspend.

I applied the patches from #1721 (comment 1077338) but they don't help.

2. When rebooting after a S0ix suspend/resume cycle, the machine throws a beep error code (Fan Error) and shuts down if not bypassed (I haven't tried to). It boots fine afterwards.

Note:

• It failed to enter suspend at all prior to v5.14.9 (SMU timeout; supposedly resolved by platform/x86: amd-pmc: Increase the response register timeout)

I've attached kernel logs of a suspend/resume cycle. Please let me know what else makes sense.

dmesg.log