From 4cba5c2103657d43d0886e4cff8004d95a3d0def Mon Sep 17 00:00:00 2001 From: Stas Sergeev Date: Mon, 20 Jul 2015 17:49:57 -0700 Subject: of_mdio: add new DT property 'managed' to specify the PHY management type Currently the PHY management type is selected by the MAC driver arbitrary. The decision is based on the presence of the "fixed-link" node and on a will of the driver's authors. This caused a regression recently, when mvneta driver suddenly started to use the in-band status for auto-negotiation on fixed links. It appears 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 string property 'managed' that allows the user to set the management type explicitly. The supported values are: "auto" - default. Uses either MDIO or nothing, depending on the presence of the fixed-link node "in-band-status" - use in-band status Signed-off-by: Stas Sergeev CC: Rob Herring CC: Pawel Moll CC: Mark Rutland CC: Ian Campbell CC: Kumar Gala CC: Florian Fainelli CC: Grant Likely CC: devicetree@vger.kernel.org CC: linux-kernel@vger.kernel.org CC: netdev@vger.kernel.org Signed-off-by: David S. Miller --- drivers/of/of_mdio.c | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-) (limited to 'drivers/of/of_mdio.c') diff --git a/drivers/of/of_mdio.c b/drivers/of/of_mdio.c index fdc60db60829..7c8c23cc6896 100644 --- a/drivers/of/of_mdio.c +++ b/drivers/of/of_mdio.c @@ -266,7 +266,8 @@ EXPORT_SYMBOL(of_phy_attach); bool of_phy_is_fixed_link(struct device_node *np) { struct device_node *dn; - int len; + int len, err; + const char *managed; /* New binding */ dn = of_get_child_by_name(np, "fixed-link"); @@ -275,6 +276,10 @@ bool of_phy_is_fixed_link(struct device_node *np) return true; } + err = of_property_read_string(np, "managed", &managed); + if (err == 0 && strcmp(managed, "auto") != 0) + return true; + /* Old binding */ if (of_get_property(np, "fixed-link", &len) && len == (5 * sizeof(__be32))) @@ -289,8 +294,18 @@ int of_phy_register_fixed_link(struct device_node *np) struct fixed_phy_status status = {}; struct device_node *fixed_link_node; const __be32 *fixed_link_prop; - int len; + int len, err; struct phy_device *phy; + const char *managed; + + err = of_property_read_string(np, "managed", &managed); + if (err == 0) { + if (strcmp(managed, "in-band-status") == 0) { + /* status is zeroed, namely its .link member */ + phy = fixed_phy_register(PHY_POLL, &status, np); + return IS_ERR(phy) ? PTR_ERR(phy) : 0; + } + } /* New binding */ fixed_link_node = of_get_child_by_name(np, "fixed-link"); -- cgit v1.2.3