in ur case i think use HKNO
check it
into method label _Q13 replace_content
begin
Store(HKNO, Local0)\n
If (LEqual(Local0,7))\n
{\n
// Brightness Down\n
Notify(\_SB.PCI0.LPCB.PS2K, 0x0405)\n
}\n
If (LEqual(Local0,8))\n
{\n
// Brightness Up\n
Notify(\_SB.PCI0.LPCB.PS2K, 0x0406)\n
}\n
If (LEqual(Local0,4))\n
{\n
// Mirror toggle\n
Notify(\_SB.PCI0.LPCB.PS2K, 0x046e)\n
}\n
end