diff options
| author | Martin Blumenstingl <martin.blumenstingl@googlemail.com> | 2017-01-22 17:41:32 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-01-24 13:31:02 -0500 |
| commit | 7630ea4bda18df2ee1c64dfdca1724a9cc32f920 (patch) | |
| tree | ebb096b59a04490bf57ee7af007cb41af8a5fbab /Documentation | |
| parent | f39aac7e839368e3895dff952f3bfa0a22e20060 (diff) | |
Documentation: net: phy: improve explanation when to specify the PHY ID
The old description basically read like "ethernet-phy-idAAAA.BBBB" can
be specified when you know the actual PHY ID. However, specifying this
has a side-effect: it forces Linux to bind to a certain PHY driver (the
one that matches the ID given in the compatible string), ignoring the ID
which is reported by the actual PHY.
Whenever a device is shipped with (multiple) different PHYs during it's
production lifetime then explicitly specifying
"ethernet-phy-idAAAA.BBBB" could break certain revisions of that device.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Rob Herring <robh@kernel.org>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/devicetree/bindings/net/phy.txt | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/Documentation/devicetree/bindings/net/phy.txt b/Documentation/devicetree/bindings/net/phy.txt index ff1bc4b1bb3b..fb5056b22685 100644 --- a/Documentation/devicetree/bindings/net/phy.txt +++ b/Documentation/devicetree/bindings/net/phy.txt @@ -19,8 +19,9 @@ Optional Properties: specifications. If neither of these are specified, the default is to assume clause 22. - If the phy's identifier is known then the list may contain an entry - of the form: "ethernet-phy-idAAAA.BBBB" where + If the PHY reports an incorrect ID (or none at all) then the + "compatible" list may contain an entry with the correct PHY ID in the + form: "ethernet-phy-idAAAA.BBBB" where AAAA - The value of the 16 bit Phy Identifier 1 register as 4 hex digits. This is the chip vendor OUI bits 3:18 BBBB - The value of the 16 bit Phy Identifier 2 register as |