I was watching a video on my Samsung 400B4B notebook running Ubuntu 14.04 when it went to sleep because of low battery level. I plugged the AC power, resumed from the sleep but now the keyboard and touchpad don't work. Restarting the system hasn't helped. I can't reboot to Windows to see if it's different there because Ubuntu is set by default in GRUB.
The built in keyboard doesn't work in BIOS or GRUB. It doesn't work in Windows, either.
However, while being in the GRUB screen, I press the arrow keys but nothing happens. Then, the timeout for default OS ends, Ubuntu loads and for a few seconds I can see on the scree somthing like
^[[A^[[B^[[A so it seems the signal from the keyboard somehow works but I can'u use it in BIOS/GRUB/OS - only USB keyboard/mouse works.
What could be the problem?