Currently for fixed-link the MAC driver decides whether to use the link status auto-negotiation or not. Unfortunately the auto-negotiation may not work when expected by the MAC driver. Sebastien Rannou explains: << Yes, I confirm that my HW does not generate an in-band status. AFAIK, it's a PHY that aggregates 4xSGMIIs to 1xQSGMII ; the MAC side of the PHY (with inband status) is connected to the switch through QSGMII, and in this context we are on the media side of the PHY. >> https://lkml.org/lkml/2015/7/10/206 This patch introduces the new boolean property 'autoneg' that allows the user to request the auto-negotiation explicitly. Signed-off-by: Stas Sergeev <stsp@xxxxxxxxxxxxxxxxxxxxx> CC: Rob Herring <robh+dt@xxxxxxxxxx> CC: Pawel Moll <pawel.moll@xxxxxxx> CC: Mark Rutland <mark.rutland@xxxxxxx> CC: Ian Campbell <ijc+devicetree@xxxxxxxxxxxxxx> CC: Kumar Gala <galak@xxxxxxxxxxxxxx> CC: Florian Fainelli <f.fainelli@xxxxxxxxx> CC: Grant Likely <grant.likely@xxxxxxxxxx> CC: devicetree@xxxxxxxxxxxxxxx CC: linux-kernel@xxxxxxxxxxxxxxx CC: netdev@xxxxxxxxxxxxxxx --- .../devicetree/bindings/net/fixed-link.txt | 6 +++++- drivers/of/of_mdio.c | 23 ++++++++++++++++++++-- include/linux/of_mdio.h | 5 +++++ 3 files changed, 31 insertions(+), 3 deletions(-) diff --git a/Documentation/devicetree/bindings/net/fixed-link.txt b/Documentation/devicetree/bindings/net/fixed-link.txt index 82bf7e0..e2959a8 100644 --- a/Documentation/devicetree/bindings/net/fixed-link.txt +++ b/Documentation/devicetree/bindings/net/fixed-link.txt @@ -9,8 +9,12 @@ Such a fixed link situation is described by creating a 'fixed-link' sub-node of the Ethernet MAC device node, with the following properties: +* 'autoneg' (boolean, optional), to enable the auto-negotiation of link + state. Auto-negotiation is MII protocol, HW and driver-specific and is + not supported in many cases, so use it only when you know what you do. * 'speed' (integer, mandatory), to indicate the link speed. Accepted - values are 10, 100 and 1000 + values are 10, 100 and 1000. If the auto-negotiation is enabled, + 'speed' may not be set. It will then be auto-negotiated, if possible. * 'full-duplex' (boolean, optional), to indicate that full duplex is used. When absent, half duplex is assumed. * 'pause' (boolean, optional), to indicate that pause should be diff --git a/drivers/of/of_mdio.c b/drivers/of/of_mdio.c index 1bd4305..12b2ede 100644 --- a/drivers/of/of_mdio.c +++ b/drivers/of/of_mdio.c @@ -280,6 +280,22 @@ bool of_phy_is_fixed_link(struct device_node *np) } EXPORT_SYMBOL(of_phy_is_fixed_link); +bool of_phy_is_autoneg_link(struct device_node *np) +{ + struct device_node *dn; + bool ret; + + dn = of_get_child_by_name(np, "fixed-link"); + if (!dn) + return false; + + ret = of_property_read_bool(dn, "autoneg"); + + of_node_put(dn); + return ret; +} +EXPORT_SYMBOL(of_phy_is_autoneg_link); + int of_phy_register_fixed_link(struct device_node *np) { struct fixed_phy_status status = {}; @@ -291,10 +307,13 @@ int of_phy_register_fixed_link(struct device_node *np) /* New binding */ fixed_link_node = of_get_child_by_name(np, "fixed-link"); if (fixed_link_node) { - status.link = 1; + bool autoneg = of_property_read_bool(fixed_link_node, + "autoneg"); + status.link = !autoneg; status.duplex = of_property_read_bool(fixed_link_node, "full-duplex"); - if (of_property_read_u32(fixed_link_node, "speed", &status.speed)) + if (of_property_read_u32(fixed_link_node, "speed", + &status.speed) != 0 && !autoneg) return -EINVAL; status.pause = of_property_read_bool(fixed_link_node, "pause"); status.asym_pause = of_property_read_bool(fixed_link_node, diff --git a/include/linux/of_mdio.h b/include/linux/of_mdio.h index d449018..647f348 100644 --- a/include/linux/of_mdio.h +++ b/include/linux/of_mdio.h @@ -65,6 +65,7 @@ static inline struct mii_bus *of_mdio_find_bus(struct device_node *mdio_np) #if defined(CONFIG_OF) && defined(CONFIG_FIXED_PHY) extern int of_phy_register_fixed_link(struct device_node *np); extern bool of_phy_is_fixed_link(struct device_node *np); +extern bool of_phy_is_autoneg_link(struct device_node *np); #else static inline int of_phy_register_fixed_link(struct device_node *np) { @@ -74,6 +75,10 @@ static inline bool of_phy_is_fixed_link(struct device_node *np) { return false; } +static inline bool of_phy_is_autoneg_link(struct device_node *np) +{ + return false; +} #endif -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
