arch/arm/lib/changebit.S


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/*
 * linux/arch/arm/lib/changebit.S
 *
 * Copyright (C) 1995-1996 Russell King
 */

#include <linux/linkage.h>
#include <asm/assembler.h>
                .text

/* Purpose  : Function to change a bit
 * Prototype: int change_bit(int bit, void *addr)
 */
ENTRY(change_bit)
		and	r2, r0, #7
		mov	r3, #1
		mov	r3, r3, lsl r2
		save_and_disable_irqs ip, r2
		ldrb	r2, [r1, r0, lsr #3]
		eor	r2, r2, r3
		strb	r2, [r1, r0, lsr #3]
		restore_irqs ip
		RETINSTR(mov,pc,lr)