struct_clk_notifier_data(9) centos man page | unix.com

STRUCT 
CLK_NOTIFIER_(9) 					  Clock Framework					   STRUCT CLK_NOTIFIER_(9)

NAME
       struct_clk_notifier_data - rate data to pass to the notifier callback

SYNOPSIS
       struct clk_notifier_data {
	 struct clk * clk;
	 unsigned long old_rate;
	 unsigned long new_rate;
       };

MEMBERS
       clk
	   struct clk * being changed

       old_rate
	   previous rate of this clk

       new_rate
	   new rate of this clk

DESCRIPTION
       For a pre-notifier, old_rate is the clk's rate before this rate change, and new_rate is what the rate will be in the future. For a
       post-notifier, old_rate and new_rate are both set to the clk's current rate (this was done to optimize the implementation).

COPYRIGHT
Kernel Hackers Manual 3.10					     June 2014						   STRUCT CLK_NOTIFIER_(9)