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/* MN10300 Non-trivial bit operations
*
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public Licence
* as published by the Free Software Foundation; either version
* 2 of the Licence, or (at your option) any later version.
*/
#include <linux/module.h>
#include <asm/bitops.h>
#include <asm/system.h>
/*
* try flipping a bit using BSET and BCLR
*/
void change_bit(int nr, volatile void *addr)
{
if (test_bit(nr, addr))
goto try_clear_bit;
try_set_bit:
if (!test_and_set_bit(nr, addr))
return;
try_clear_bit:
if (test_and_clear_bit(nr, addr))
return;
goto try_set_bit;
}
/*
* try flipping a bit using BSET and BCLR and returning the old value
*/
int test_and_change_bit(int nr, volatile void *addr)
{
if (test_bit(nr, addr))
goto try_clear_bit;
try_set_bit:
if (!test_and_set_bit(nr, addr))
return 0;
try_clear_bit:
if (test_and_clear_bit(nr, addr))
return 1;
goto try_set_bit;
}
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