[ARM] Add lubbock_set_misc_wr()

This provides an atomic method to update the Lubbock board specific
register from various drivers.

arch/arm/mach-pxa/lubbock.c

@@ -11,6 +11,7 @@
  *  it under the terms of the GNU General Public License version 2 as
  *  published by the Free Software Foundation.
  */
+#include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/device.h>
@@ -34,6 +35,16 @@
 #include "generic.h"
 
 
+void lubbock_set_misc_wr(unsigned int mask, unsigned int set)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+	LUB_MISC_WR = (LUB_MISC_WR & ~mask) | (set & mask);
+	local_irq_restore(flags);
+}
+EXPORT_SYMBOL(lubbock_set_misc_wr);
+
 static unsigned long lubbock_irq_enabled;
 
 static void lubbock_mask_irq(unsigned int irq)

include/asm-arm/arch-pxa/lubbock.h

@@ -35,3 +35,6 @@
 #define LUB_IRQ_SET_CLR		__LUB_REG(LUBBOCK_FPGA_PHYS + 0x0d0)
 #define LUB_GP			__LUB_REG(LUBBOCK_FPGA_PHYS + 0x100)
 
+#ifndef __ASSEMBLY__
+extern void lubbock_set_misc_wr(unsigned int mask, unsigned int set);
+#endif