| /* 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; |
| } |