PTP Hardware Clock devices appear as class devices in sysfs. This patch changes the registration API to use the parent device, clarifying the clock's relationship to the underlying device. Signed-off-by: Richard Cochran <richardcochran@gmail.com> Acked-by: Ben Hutchings <bhutchings@solarflare.com> Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>