int_to_frac
tz->tzp->k_po = int_to_frac(sustainable_power) /
tz->tzp->k_pu = int_to_frac(2 * sustainable_power) /
max_power_frac = int_to_frac(max_allocatable_power);
err = int_to_frac(err);
if (err < int_to_frac(tz->tzp->integral_cutoff)) {