+ struct tg3 *tp = container_of(ptp, struct tg3, ptp_info);
+ u32 clock_ctl;
+ int rval = 0;
+
+ switch (rq->type) {
+ case PTP_CLK_REQ_PEROUT:
+ if (rq->perout.index != 0)
+ return -EINVAL;
+
+ tg3_full_lock(tp, 0);
+ clock_ctl = tr32(TG3_EAV_REF_CLCK_CTL);
+ clock_ctl &= ~TG3_EAV_CTL_TSYNC_GPIO_MASK;
+
+ if (on) {
+ u64 nsec;
+
+ nsec = rq->perout.start.sec * 1000000000ULL +
+ rq->perout.start.nsec;
+
+ if (rq->perout.period.sec || rq->perout.period.nsec) {
+ netdev_warn(tp->dev,
+ "Device supports only a one-shot timesync output, period must be 0\n");
+ rval = -EINVAL;
+ goto err_out;
+ }
+
+ if (nsec & (1ULL << 63)) {
+ netdev_warn(tp->dev,
+ "Start value (nsec) is over limit. Maximum size of start is only 63 bits\n");
+ rval = -EINVAL;
+ goto err_out;
+ }
+
+ tw32(TG3_EAV_WATCHDOG0_LSB, (nsec & 0xffffffff));
+ tw32(TG3_EAV_WATCHDOG0_MSB,
+ TG3_EAV_WATCHDOG0_EN |
+ ((nsec >> 32) & TG3_EAV_WATCHDOG_MSB_MASK));
+
+ tw32(TG3_EAV_REF_CLCK_CTL,
+ clock_ctl | TG3_EAV_CTL_TSYNC_WDOG0);
+ } else {
+ tw32(TG3_EAV_WATCHDOG0_MSB, 0);
+ tw32(TG3_EAV_REF_CLCK_CTL, clock_ctl);
+ }
+
+err_out:
+ tg3_full_unlock(tp);
+ return rval;
+
+ default:
+ break;
+ }
+