ktime_ms_delta
*time_ms = ktime_ms_delta(etime, stime);
commit_time_ms = ktime_ms_delta(ktime_get(), start);
panel_power_off_duration = ktime_ms_delta(panel_power_on_time,
panel_power_off_duration = ktime_ms_delta(panel_power_on_time, intel_dp->pps.panel_power_off_time);
bool ret = ktime_ms_delta(ktime_get(), ct->stall_time) > timeout;
ktime_ms_delta(ktime_get(), ct->stall_time),