/* 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> /* * try flipping a bit using BSET and BCLR */ void change_bit(unsigned long 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(unsigned long 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; } |