[ARM] S3C6XX: Add enable for clk_48

Add apropriate enable call for clk_48m.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
diff --git a/arch/arm/plat-s3c64xx/clock.c b/arch/arm/plat-s3c64xx/clock.c
index 2d2e83a..523da0c 100644
--- a/arch/arm/plat-s3c64xx/clock.c
+++ b/arch/arm/plat-s3c64xx/clock.c
@@ -22,6 +22,7 @@
 #include <mach/hardware.h>
 #include <mach/map.h>
 
+#include <plat/regs-sys.h>
 #include <plat/regs-clock.h>
 #include <plat/cpu.h>
 #include <plat/devs.h>
@@ -33,10 +34,31 @@
 	.rate		= 27000000,
 };
 
+static int clk_48m_ctrl(struct clk *clk, int enable)
+{
+	unsigned long flags;
+	u32 val;
+
+	/* can't rely on clock lock, this register has other usages */
+	local_irq_save(flags);
+
+	val = __raw_readl(S3C64XX_OTHERS);
+	if (enable)
+		val |= S3C64XX_OTHERS_USBMASK;
+	else
+		val &= ~S3C64XX_OTHERS_USBMASK;
+
+	__raw_writel(val, S3C64XX_OTHERS);
+	local_irq_restore(flags);
+
+	return 0;
+}
+
 struct clk clk_48m = {
 	.name		= "clk_48m",
 	.id		= -1,
 	.rate		= 48000000,
+	.enable		= clk_48m_ctrl,
 };
 
 static int inline s3c64xx_gate(void __iomem *reg,
diff --git a/arch/arm/plat-s3c64xx/include/plat/regs-sys.h b/arch/arm/plat-s3c64xx/include/plat/regs-sys.h
new file mode 100644
index 0000000..d8ed829
--- /dev/null
+++ b/arch/arm/plat-s3c64xx/include/plat/regs-sys.h
@@ -0,0 +1,24 @@
+/* arch/arm/plat-s3c64xx/include/plat/regs-sys.h
+ *
+ * Copyright 2008 Openmoko, Inc.
+ * Copyright 2008 Simtec Electronics
+ *	Ben Dooks <ben@simtec.co.uk>
+ *	http://armlinux.simtec.co.uk/
+ *
+ * S3C64XX system register definitions
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+*/
+
+#ifndef __PLAT_REGS_SYS_H
+#define __PLAT_REGS_SYS_H __FILE__
+
+#define S3C_SYSREG(x)		(S3C_VA_SYS + (x))
+
+#define S3C64XX_OTHERS		S3C_SYSREG(0x900)
+
+#define S3C64XX_OTHERS_USBMASK	(1 << 16)
+
+#endif /* _PLAT_REGS_SYS_H */