net: enetc: fix incorrect fallback PHY address handling

The current netc_get_phy_addr() implementation falls back to PHY address
0 when the "mdio" node or the PHY child node is missing. On i.MX95, this
causes failures when a real PHY is actually assigned address 0 and is
managed through the EMDIO interface. Because the bit 0 of phy_mask will
be set, leading imx95_enetc_mdio_phyaddr_config() to return an error, and
the netc_blk_ctrl driver probe subsequently fails. Fix this by returning
-ENODEV when neither an "mdio" node nor any PHY node is present, it means
that ENETC port MDIO is not used to manage the PHY, so there is no need
to configure LaBCR[MDIO_PHYAD_PRTAD].

Reported-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Closes: https://lore.kernel.org/all/7825188.GXAFRqVoOG@steina-w
Fixes: 6633df05f3ad ("net: enetc: set the external PHY address in IERB for port MDIO usage")
Reviewed-by: Clark Wang <xiaoning.wang@nxp.com>
Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Wei Fang <wei.fang@nxp.com>
Link: https://patch.msgid.link/20260305031211.904812-2-wei.fang@nxp.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

0 files changed, 0 insertions, 0 deletions