if u remember correctly, i asked you to turn off your phone an take out the battery and wait for couple of mins before putting it back again.
( i may have not said it, rather shared a link)
the battery might be powering a cache that might be holding on to something that was preventing your camera driver from being started.
Thats what I think the problem might be,
I had the same issue and simply taking out the battery for 5 mins solved the issue.