This fixes an overflow condition that can happen with high max
brightness and period values in compute_duty_cycle. This fixes it by
using a 64 bit variable for computing the duty cycle.
Signed-off-by: NDerek Basehore <dbasehore@chromium.org>
Acked-by: NThierry Reding <thierry.reding@gmail.com>
Reviewed-by: NBrian Norris <briannorris@chromium.org>
Signed-off-by: NLee Jones <lee.jones@linaro.org>