How to get suspend working on A04?

When I try to wake the suspended A04 by pressing the power button the screen flashes to the last pre-suspend state for a moment and then goes dark and is unresponsive. I’m forced to hard reset by long-pressing the power button. Other common wake methods don’t wake the device (i.e. pushing keyboard buttons, clicking mouse, etc.). The power button seems to be the only one to produce a result (with this error).

I found a post indicating that suspend is a problem for A06. Is suspend also a problem for A04? Or is there something I’m doing wrong?

The chip used by A04 is Allwinner H6, which is not support suspend from hardware.

(A06 suspend to ram seems already usable, thanks to @yatli

Thanks. Are you sure though? Suspending to RAM on A04 behaves a lot like it’s working (it just doesn’t wake up properly).

I’ve continued fiddling and found an interesting workaround. If I suspend then wake with the power button I get the strange blank screen. But if I plug in the USB-C power before pressing power it seems to wake properly. And an even weirder observation: if I disconnect the power and suspend again, then press power to wake (without connecting USB-C), then it wakes OK!

So it seems that connecting USB-C power, even temporarily, helps resolve the wake up problem.