[ARM] 5602/1: Add sub clock api for w90p910 platform

Add sub clock api for w90p910 platform.

Signed-off-by: Wan ZongShun <mcuos.com@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mach-w90x900/clock.c b/arch/arm/mach-w90x900/clock.c
index f420613..49cf1fb 100644
--- a/arch/arm/mach-w90x900/clock.c
+++ b/arch/arm/mach-w90x900/clock.c
@@ -25,6 +25,8 @@
 
 #include "clock.h"
 
+#define SUBCLK 0x24
+
 static DEFINE_SPINLOCK(clocks_lock);
 
 int clk_enable(struct clk *clk)
@@ -68,6 +70,22 @@
 	__raw_writel(clken, W90X900_VA_CLKPWR);
 }
 
+void w90x900_subclk_enable(struct clk *clk, int enable)
+{
+	unsigned int clocks = clk->cken;
+	unsigned long clken;
+
+	clken = __raw_readl(W90X900_VA_CLKPWR + SUBCLK);
+
+	if (enable)
+		clken |= clocks;
+	else
+		clken &= ~clocks;
+
+	__raw_writel(clken, W90X900_VA_CLKPWR + SUBCLK);
+}
+
+
 void clks_register(struct clk_lookup *clks, size_t num)
 {
 	int i;