mb/system76/meer9: Add power_on_after_fail

[crawfxrd]

Configure SuperIO for BIOS control of power loss behavior and add CMOS option to allow user control.

Enum 1 is used instead of 7 as the Keep option does not seem to work on meer9. The same setting via SIO control (CRE4) does work, though.

Test

With default value of Disable:

• Unit remains off after unplugging and plugging AC power while on or off

With value of Enable:

• Unit turns back on after unplugging and plugging AC power while on or off

[leviport]

Enabled and Disabled are both working nicely, but I'm seeing some weirdness with Keep.

After first flashing firmware with Keep set, an AC loss and restore powers the machine back on as expected. Then if I power the machine off manually, then lose and restore AC power, the machine stays off, as expected. But after this point, the machine acts like it's set to Disable. Whether or not the machine is running first, or shut down manually first, yanking power and plugging it back in results in the machine staying off.

As far as options we're displaying in the BIOS selector, I think just being able to switch between Enabled and Disabled seems like it should be sufficient. If that seems reasonable to everyone, I'll approve.

wrong button

[leviport]

I meant to comment, not request changes. I'll re-review once we've reached a consensus.

[crawfxrd]

CR E4h:

1 1: User defines the resuming state before power loss.(refer to Logical Device A, CRE6[4])

So it probably needs to write this bit as well.

---

Bit is inverted and set to ON by default.

SIO control (0b10) works correctly.

[crawfxrd]

enum changed to 1 to disallow broken Keep option until the issue is addressed.

[leviport]

Enable and Disable are both working as expected on meer9. I did not try Keep again.