[ARM] 3628/1: S3C24XX: add get_rate call to struct clk

Patch from Ben Dooks

Add a get_rate call to allow an given clock
to over-ride the clk_get_rate() call.

This provides support for clocks which rely on
division of their parent to correctly report
their frequency when the parent can also change.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/mach-s3c2410/clock.c

@@ -148,8 +148,11 @@ unsigned long clk_get_rate(struct clk *clk)
 	if (clk->rate != 0)
 		return clk->rate;
 
-	while (clk->parent != NULL && clk->rate == 0)
-		clk = clk->parent;
+	if (clk->get_rate != NULL)
+		return (clk->get_rate)(clk);
+
+	if (clk->parent != NULL)
+		return clk_get_rate(clk->parent);
 
 	return clk->rate;
 }

arch/arm/mach-s3c2410/clock.h

@@ -22,6 +22,7 @@ struct clk {
 
 	int		    (*enable)(struct clk *, int enable);
 	int		    (*set_rate)(struct clk *c, unsigned long rate);
+	unsigned long	    (*get_rate)(struct clk *c);
 	unsigned long	    (*round_rate)(struct clk *c, unsigned long rate);
 	int		    (*set_parent)(struct clk *c, struct clk *parent);
 };