Add the missing unlock before return from function idtcm_probe()
in the error handling case.
Fixes: 3a6ba7dc7799 ("ptp: Add a ptp clock driver for IDT ClockMatrix.")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: Vincent Cheng <vincent.cheng.xh@renesas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
 
        err = set_tod_write_overhead(idtcm);
 
-       if (err)
+       if (err) {
+               mutex_unlock(&idtcm->reg_lock);
                return err;
+       }
 
        err = idtcm_load_firmware(idtcm, &client->dev);