Macbook Pro deja vu part 2

Hi everyone,

Since november 2013 I think , I have a strange problem n haven't solved until now, the screen brightness control adn the auto graphics switch funtion are disappeared!!!!

I thought it will come back by themselves because sometime my cMBP have some function disappear by itself n come back on next start up again(example can't click in a doc in quick view to quick excess to preview app), now this two problem I have really no idea how they can be gone(I reset nvram and smc also didn't help!!!)

SO anyone have the same problem please do share yr experience here to help me out!!!

Thanks everyone have a nice day!!!! 😀