void clockevents_register_device(struct clock_event_device *dev);

void clockevents_config_and_register(struct clock_event_device *dev,
         u32 freq, unsigned long min_delta,
         unsigned long max_delta);

相關的一個是配置函式

void clockevents_config(struct clock_event_device *dev, u32 freq);

/**  * clockevents_register_device - register a clock event device  * @dev: device to register  */ void clockevents_register_device(struct clock_event_device *dev) {  unsigned long flags;

 /* Initialize state to DETACHED */  clockevent_set_state(dev, CLOCK_EVT_STATE_DETACHED);

 if (!dev->cpumask) {   WARN_ON(num_possible_cpus() > 1);   dev->cpumask = cpumask_of(smp_processor_id());  }

 raw_spin_lock_irqsave(&clockevents_lock, flags);

 list_add(&dev->list, &clockevent_devices);  tick_check_new_device(dev);  clockevents_notify_released();

 raw_spin_unlock_irqrestore(&clockevents_lock, flags); } EXPORT_SYMBOL_GPL(clockevents_register_device);

/**
 * clockevents_config_and_register - Configure and register a clock event device
 * @dev: device to register
 * @freq: The clock frequency
 * @min_delta: The minimum clock ticks to program in oneshot mode
 * @max_delta: The maximum clock ticks to program in oneshot mode
 *
 * min/max_delta can be 0 for devices which do not support oneshot mode.
 */
void clockevents_config_and_register(struct clock_event_device *dev,
         u32 freq, unsigned long min_delta,
         unsigned long max_delta)
{
 dev->min_delta_ticks = min_delta;
 dev->max_delta_ticks = max_delta;
 clockevents_config(dev, freq);
 clockevents_register_device(dev);
}
EXPORT_SYMBOL_GPL(clockevents_config_and_register);

void clockevents_config(struct clock_event_device *dev, u32 freq) {  u64 sec;

 if (!(dev->features & CLOCK_EVT_FEAT_ONESHOT))   return;

 /*   * Calculate the maximum number of seconds we can sleep. Limit   * to 10 minutes for hardware which can program more than   * 32bit ticks so we still get reasonable conversion values.   */  sec = dev->max_delta_ticks;  do_div(sec, freq);  if (!sec)   sec = 1;  else if (sec > 600 && dev->max_delta_ticks > UINT_MAX)   sec = 600;

 clockevents_calc_mult_shift(dev, freq, sec);  dev->min_delta_ns = cev_delta2ns(dev->min_delta_ticks, dev, false);  dev->max_delta_ns = cev_delta2ns(dev->max_delta_ticks, dev, true); }