Also I expect when nas is running the switch is in on position. When moving it to off what happens now? Can you test that.
The NAS is running with the switch in the ON position, and from my testing, if I switch it off during the countdown to auto boot, it will power off the NAS.
As the NAS is booting, there is no effect from the power switch at all.
After the NAS has been booted and the gpiokeys module has been loaded, there is also no effect on the NAS, and nothing shows on the serial output.
I would concur that there's really no specific reason to integrate the power switch into kernel if the tasks can be performed from the front button. I just wasn't sure if there was something there previously, or it was just something that had to be phased out from an older revision.