http://www.shouselaw.com/open-carry.html
If you'd like to know more, check http://www.calguns.net
While most will poo poo the State of California, we should all realize the US Supreme Court now "has the ball" and Justice Samuel Alito is no more. What starts in California, usually comes to all of America, much faster than anyone expects.
If the court believes the 2nd does not allow CCW, it clearly does not forbid it either. From their view it seems to state the 2nd is silent on CCW. However, I believe a little research will show past courts have upheld the right for CCW which is the proper interpretation
an interesting aside: before and early in WWII, the Japanese were considering an invasion of the US mainland, California probably being the target area. The one thing which held them back was their understanding that every American home was protected by firearms.