Currently for fixed-link the link state is always set to UP. This patch introduces the new property 'link' that accepts the following string arguments: "up", "down" and "auto". "down" may be needed if the link is physically unconnected. "auto" is needed to enable the link paramaters auto-negotiation, that is built into some MII protocols, namely SGMII. The appropriate documentation is added and explicitly states that "auto" is very specific (protocol, HW and driver-specific), and is therefore should be used with care. 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 | 8 +++- drivers/of/of_mdio.c | 48 ++++++++++++++++++++-- include/linux/of_mdio.h | 5 +++ 3 files changed, 57 insertions(+), 4 deletions(-) diff --git a/Documentation/devicetree/bindings/net/fixed-link.txt b/Documentation/devicetree/bindings/net/fixed-link.txt index 82bf7e0..070f554 100644 --- a/Documentation/devicetree/bindings/net/fixed-link.txt +++ b/Documentation/devicetree/bindings/net/fixed-link.txt @@ -9,8 +9,14 @@ Such a fixed link situation is described by creating a 'fixed-link' sub-node of the Ethernet MAC device node, with the following properties: +* 'link' (string, optional), to indicate the link state. Accepted + values are "up", "down" and "auto". "auto" means auto-negotiation of + link parameters. 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 'link' property is set to 'auto', + '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..2152cf8 100644 --- a/drivers/of/of_mdio.c +++ b/drivers/of/of_mdio.c @@ -280,6 +280,26 @@ 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; + const char *link_str; + int rc; + bool ret = false; + + dn = of_get_child_by_name(np, "fixed-link"); + if (!dn) + return false; + + rc = of_property_read_string(dn, "link", &link_str); + if (rc == 0 && strcmp(link_str, "auto") == 0) + ret = true; + + 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 = {}; @@ -291,11 +311,33 @@ 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; + const char *link_str; + int ret; + bool link_auto = false; + + ret = of_property_read_string(fixed_link_node, "link", + &link_str); + if (ret == 0) { + if (strcmp(link_str, "up") == 0) + status.link = 1; + else + status.link = 0; + if (strcmp(link_str, "auto") == 0) + link_auto = true; + } else { + status.link = 1; + } status.duplex = of_property_read_bool(fixed_link_node, "full-duplex"); - if (of_property_read_u32(fixed_link_node, "speed", &status.speed)) - return -EINVAL; + if (of_property_read_u32(fixed_link_node, "speed", + &status.speed) != 0) { + /* in auto mode just set to some sane value: + * it will be changed by MAC later */ + if (link_auto) + status.speed = 1000; + else + return -EINVAL; + } status.pause = of_property_read_bool(fixed_link_node, "pause"); status.asym_pause = of_property_read_bool(fixed_link_node, "asym-pause"); 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