static int idtcm_enable_extts()

in ptp_clockmatrix.c [279:311]

• 29 lines of code
• 8 McCabe index (conditional complexity)

static int idtcm_enable_extts(struct idtcm_channel *channel, u8 todn, u8 ref,
			      bool enable)
{
	struct idtcm *idtcm = channel->idtcm;
	u8 old_mask = idtcm->extts_mask;
	u8 mask = 1 << todn;
	int err = 0;

	if (todn >= MAX_TOD)
		return -EINVAL;

	if (enable) {
		if (ref > 0xF) /* E_REF_CLK15 */
			return -EINVAL;
		if (idtcm->extts_mask & mask)
			return 0;
		err = _idtcm_set_scsr_read_trig(&idtcm->channel[todn],
						SCSR_TOD_READ_TRIG_SEL_REFCLK,
						ref);
		if (err == 0) {
			idtcm->extts_mask |= mask;
			idtcm->event_channel[todn] = channel;
			idtcm->channel[todn].refn = ref;
		}
	} else
		idtcm->extts_mask &= ~mask;

	if (old_mask == 0 && idtcm->extts_mask)
		schedule_delayed_work(&idtcm->extts_work,
				      msecs_to_jiffies(EXTTS_PERIOD_MS));

	return err;
}