Explicit if SDA is input or output in static functions
Do not use logf() but return codes
Check for overflow when adding an interface
Indent on 4 spaces
Rewrite i2c_read_data() and i2c_write_data() using goto for error cases
Make subaddress optional (not sent if == -1)
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@19360 a1c6a512-1295-4272-9138-f99709370657
