path: root/Documentation
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authorStas Sergeev <stsp@list.ru>2015-07-20 17:49:57 -0700
committerSasha Levin <sasha.levin@oracle.com>2015-10-27 09:33:12 -0400
commit71a386c7a6a1cf88c712f39e9e60fead672846c5 (patch)
treee1dfd0ca93d43afd054286dd97af21b812dbfd86 /Documentation
parentc0fb099370bcd7dd1956a787efbec35584d00117 (diff)
of_mdio: add new DT property 'managed' to specify the PHY management type
[ Upstream commit 4cba5c2103657d43d0886e4cff8004d95a3d0def ] 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 <stsp@users.sourceforge.net> CC: Rob Herring <robh+dt@kernel.org> CC: Pawel Moll <pawel.moll@arm.com> CC: Mark Rutland <mark.rutland@arm.com> CC: Ian Campbell <ijc+devicetree@hellion.org.uk> CC: Kumar Gala <galak@codeaurora.org> CC: Florian Fainelli <f.fainelli@gmail.com> CC: Grant Likely <grant.likely@linaro.org> CC: devicetree@vger.kernel.org CC: linux-kernel@vger.kernel.org CC: netdev@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Diffstat (limited to 'Documentation')
1 files changed, 4 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/net/ethernet.txt b/Documentation/devicetree/bindings/net/ethernet.txt
index 3fc360523bc9..cb115a3b7e00 100644
--- a/Documentation/devicetree/bindings/net/ethernet.txt
+++ b/Documentation/devicetree/bindings/net/ethernet.txt
@@ -19,7 +19,11 @@ The following properties are common to the Ethernet controllers:
- phy: the same as "phy-handle" property, not recommended for new bindings.
- phy-device: the same as "phy-handle" property, not recommended for new
+- managed: string, specifies the PHY management type. Supported values are:
+ "auto", "in-band-status". "auto" is the default, it usess MDIO for
+ management if fixed-link is not specified.
Child nodes of the Ethernet controller are typically the individual PHY devices
connected via the MDIO bus (sometimes the MDIO bus controller is separate).
They are described in the phy.txt file in this same directory.
+For non-MDIO PHY management see fixed-link.txt.