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author | fishsoupisgood <github@madingley.org> | 2020-06-13 21:05:45 +0100 |
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committer | fishsoupisgood <github@madingley.org> | 2020-06-13 21:05:45 +0100 |
commit | d85f3aeeeefd6926fe71ec8e066adb74f62dc1cc (patch) | |
tree | fc4e43a80dc50717d41a869dddce20c94a0f25c4 /app/i2c.c | |
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fish
Diffstat (limited to 'app/i2c.c')
-rw-r--r-- | app/i2c.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/app/i2c.c b/app/i2c.c new file mode 100644 index 0000000..bf25256 --- /dev/null +++ b/app/i2c.c @@ -0,0 +1,20 @@ +static int mutex = 0; + +int +i2c_lock (void) +{ + if (__sync_add_and_fetch (&mutex, 1) != 1) + { + __sync_sub_and_fetch (&mutex, 1); + return -1; + } + + return 0; +} + + +void +i2c_unlock (void) +{ + __sync_sub_and_fetch (&mutex, 1); +} |