The mapping from the 16-bit EEPROM value to the decimal 0-1 range is
approximate. A special case ensures 0xFFFF shows as 1.0 instead of
0.999998565.
Writing to EEPROM requires an explicit erase by writing zero. In
addition, it takes 20ms for the erase/write to complete. During this
time no EEPROM register should be accessed. Therefore, two msleep()s
are added to the write function and a mutex protects against concurrent
access.
Signed-off-by: Vianney le Clément de Saint-Marcq <vianney.leclement@essensium.com>
Cc: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
fad65a8fe5