Dealing with "provided value did not match any possible option"

Start by reproducing the behavior with uefisettings hii show-ifr, hii get, and hii set for Restore On AC Power Loss on the reported motherboard. Trace how the HII question options are exposed and validated, then determine whether the command can set the firmware value or should report it as unsupported; done means the behavior is clarified or a reproducible fix is covered by tests.

Thanks for this tool. I'm trying to change my BIOS setting to restore power after external power is lost (it's a remote server, so it is difficult to go hook up a KB and monitor to do this).

The server is running an Asrock AB350 motherboard, and I can see a few relevant parameters in the output of uefisettings hii show-ifr:

        OpCode: Form
            OpCode: Subtitle - S: 
                OpCode: EqIdVal
                OpCode: OneOf - Q: Restore On AC Power Loss - Help: Restore Status On AC Power Loss
                -Range8(Range8 { min_value: 1, max_value: 2, step: 0 })
                -Answer: Unknown
                    OpCode: OneOfOption - S: Power On
                    -ValueType:0
                    -Value:NumSize8(1)
                    OpCode: OneOfOption - S: Power Off
                    -ValueType:0
                    -Value:NumSize8(2)
                OpCode: OneOf - Q: GPIO Devices Support - Help: Enable/Disable GPIO ACPI Devices Support, disable it will disable i2C and uart interface device.
                -Range8(Range8 { min_value: 1, max_value: 255, step: 0 })
                -Answer: Unknown
                    OpCode: OneOfOption - S: Enabled
                    -ValueType:0
                    -Value:NumSize8(1)
                    OpCode: OneOfOption - S: Auto
                    -ValueType:0
                    -Value:NumSize8(255)

Likewise, in the list-strings output, I see that "Restore On AC Power Loss" as well:

            469: "Restore On AC Power Loss",
            470: "Restore Status On AC Power Loss",

If I get that value, it gives the following output:

$ sudo uefisettings hii get "Restore On AC Power Loss"
GetResponseList {
    responses: [
        GetResponse {
            selector: "899407D7-99FE-43D8-9A21-79EC328CAC21",
            backend: Backend::Hii,
            question: Question {
                name: "Restore On AC Power Loss",
                answer: "Unknown",
                options: [],
                help: "Restore Status On AC Power Loss",
            },
            is_translated: false,
        },
    ],
}

But if I try to set the value to one of the options indicated by show-ifr, I get an error:

$ sudo uefisettings hii set "Restore On AC Power Loss" "Power On"
{"error_message":"provided value did not match any possible option"}

I assume this is because there are no options allowed in the Question output above. Is there any way to set this value on my motherboard, or is this just likely unsupported?

Thanks for your help.

This is on a Linux (TrueNAS scale) system:

$ uname -a
Linux truenas 6.1.55-production+truenas #2 SMP PREEMPT_DYNAMIC Tue Oct 31 16:07:08 UTC 2023 x86_64 GNU/Linux