[PATCH] serial: samsung: protect NULL dereference of clock name

[Kyoungil Kim]

Shubhrajyoti Datta wrote:
> Hi Kim,
> On Wed, May 30, 2012 at 1:59 PM, Kyoungil Kim <ki0351.kim at samsung.com> wrote:
> > From: KeyYoung Park <keyyoung.park at samsung.com>
> >
> > When priting the serial clock source, if clock source name is null,
> > kernel reference NULL point.
> >
> Could you help me understand why is that NULL ? Or the crash that you saw.

When you want to see the serial clock source name like using cat command before you open the tty, 
You can see the kernel crash.
I know this is not normal scenario.
This patch just prevents the kernel panic.