static int do_phase_pull_in_sw()

in ptp_clockmatrix.c [1573:1614]

• 27 lines of code
• 5 McCabe index (conditional complexity)

static int do_phase_pull_in_sw(struct idtcm_channel *channel,
			       s32 delta_ns,
			       u32 max_ffo_ppb)
{
	s32 current_ppm = channel->current_freq_scaled_ppm;
	u32 duration_ms = MSEC_PER_SEC;
	s32 delta_ppm;
	s32 ppb;
	int err;

	/* If the ToD correction is less than PHASE_PULL_IN_MIN_THRESHOLD_NS,
	 * skip. The error introduced by the ToD adjustment procedure would
	 * be bigger than the required ToD correction
	 */
	if (abs(delta_ns) < PHASE_PULL_IN_MIN_THRESHOLD_NS)
		return 0;

	if (max_ffo_ppb == 0)
		max_ffo_ppb = PHASE_PULL_IN_MAX_PPB;

	/* For most cases, keep phase pull-in duration 1 second */
	ppb = delta_ns;
	while (abs(ppb) > max_ffo_ppb) {
		duration_ms *= 2;
		ppb /= 2;
	}

	delta_ppm = phase_pull_in_scaled_ppm(current_ppm, ppb);

	err = _idtcm_adjfine(channel, delta_ppm);

	if (err)
		return err;

	/* schedule the worker to cancel phase pull-in */
	ptp_schedule_worker(channel->ptp_clock,
			    msecs_to_jiffies(duration_ms) - 1);

	channel->phase_pull_in = true;

	return 0;
}