sysutils/dec-hw: Power Supply 1 always shown as off

[nedic-eworks]

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Describe the bug
On the DEC3960 platform (DEC3900 series, Netboard A20 Gen2), the sysutils/dec-hw plugin reports incorrect power supply status.

The plugin reads PSU status via:

gpioctl -f /dev/gpioc0 4   # PSU1
gpioctl -f /dev/gpioc0 5   # PSU2

Observed behavior:

GPIO pin 4 (PSU1) is always false, even when PSU1 is powered and LED indicates normal operation.
GPIO pin 5 (PSU2) changes to false only after ~2 minutes when PSU2 is disconnected.
When PSU2 is reconnected, the pin immediately returns to true.

Hardware behavior:

PSU1 LED reacts immediately to power changes (expected).
PSU2 LED turns red with a delay (~2 minutes) when disconnected, but immediately returns to normal when reconnected.

Additional notes:

Issue reproduced on two separate DEC3960 devices.
This suggests incorrect GPIO mapping and/or changed signal behavior on this platform.
PSU2 signal appears to be delayed (possibly controller-mediated), not a direct presence signal.

Expected behavior:

Correct and immediate PSU status for both power supplies.
Proper GPIO mapping for DEC3960 platform.

Conclusion:
The current GPIO mapping used by the plugin (pins 4 and 5 on /dev/gpioc0) appears to be incompatible with the DEC3960 hardware.

Environment

• OPNsense business edition 26.4-amd64
• os-dec-hw plugin version 1.1_3
• Hardware DEC3960

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@nedic-eworks please contact our sales with the serial number, could be a hardware issue, which we like to rule out.