From 5fbb08eb7f945c7e8896ea39f03143ce66dfa4c7 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Thu, 18 Aug 2022 17:32:50 +0300 Subject: net: dsa: microchip: keep compatibility with device tree blobs with no phy-mode MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit DSA has multiple ways of specifying a MAC connection to an internal PHY. One requires a DT description like this: port@0 { reg = <0>; phy-handle = <&internal_phy>; phy-mode = "internal"; }; (which is IMO the recommended approach, as it is the clearest description) but it is also possible to leave the specification as just: port@0 { reg = <0>; } and if the driver implements ds->ops->phy_read and ds->ops->phy_write, the DSA framework "knows" it should create a ds->slave_mii_bus, and it should connect to a non-OF-based internal PHY on this MDIO bus, at an MDIO address equal to the port address. There is also an intermediary way of describing things: port@0 { reg = <0>; phy-handle = <&internal_phy>; }; In case 2, DSA calls phylink_connect_phy() and in case 3, it calls phylink_of_phy_connect(). In both cases, phylink_create() has been called with a phy_interface_t of PHY_INTERFACE_MODE_NA, and in both cases, PHY_INTERFACE_MODE_NA is translated into phy->interface. It is important to note that phy_device_create() initializes dev->interface = PHY_INTERFACE_MODE_GMII, and so, when we use phylink_create(PHY_INTERFACE_MODE_NA), no one will override this, and we will end up with a PHY_INTERFACE_MODE_GMII interface inherited from the PHY. All this means that in order to maintain compatibility with device tree blobs where the phy-mode property is missing, we need to allow the "gmii" phy-mode and treat it as "internal". Fixes: 2c709e0bdad4 ("net: dsa: microchip: ksz8795: add phylink support") Link: https://bugzilla.kernel.org/show_bug.cgi?id=216320 Reported-by: Craig McQueen Signed-off-by: Vladimir Oltean Reviewed-by: Alvin Šipraga Tested-by: Rasmus Villemoes Link: https://lore.kernel.org/r/20220818143250.2797111-1-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski --- drivers/net/dsa/microchip/ksz_common.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'drivers/net/dsa/microchip') diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c index ed7d137cba99..7461272a6d41 100644 --- a/drivers/net/dsa/microchip/ksz_common.c +++ b/drivers/net/dsa/microchip/ksz_common.c @@ -803,9 +803,15 @@ static void ksz_phylink_get_caps(struct dsa_switch *ds, int port, if (dev->info->supports_rgmii[port]) phy_interface_set_rgmii(config->supported_interfaces); - if (dev->info->internal_phy[port]) + if (dev->info->internal_phy[port]) { __set_bit(PHY_INTERFACE_MODE_INTERNAL, config->supported_interfaces); + /* Compatibility for phylib's default interface type when the + * phy-mode property is absent + */ + __set_bit(PHY_INTERFACE_MODE_GMII, + config->supported_interfaces); + } if (dev->dev_ops->get_caps) dev->dev_ops->get_caps(dev, port, config); -- cgit v1.2.3-59-g8ed1b