[ Upstream commit8f28980561] Fix fixed_phy not checking GPIO if no link_update callback is registered. In the original version all users registered a link_update callback so the issue was masked. Fixes:a5597008db("phy: fixed_phy: Add gpio to determine link up/down.") Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Moritz Fischer <mdf@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>