[PATCH v4 3/6] clk: introduce the common clock framework

[Richard Zhao]

Hi Mike,
> + *
> + * @recalc_rate	Recalculate the rate of this clock, by quering hardware
> + * 		and/or the clock's parent. It is up to the caller to insure
> + * 		that the prepare_mutex is held across this call.  Returns the
> + * 		calculated rate.  Optional, but recommended - if this op is not
> + * 		set then clock rate will be initialized to 0.
I'm still concerned, if it's NULL, why don't just retrun parent's rate if it has? 
 
Thanks
Richard