dt-bindings: net: cpsw: Document cpsw-phy-sel usage but prefer phandle

The current cpsw usage for cpsw-phy-sel is undocumented but is used for
all the boards using cpsw. And cpsw-phy-sel is not really a child of
the cpsw device, it lives in the system control module instead.

Let's document the existing usage, and improve it a bit where we prefer
to use a phandle instead of a child device for it. That way we can
properly describe the hardware in dts files for things like genpd.

Cc: devicetree@vger.kernel.org
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Murali Karicheri <m-karicheri2@ti.com>
Cc: Rob Herring <robh+dt@kernel.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/Documentation/devicetree/bindings/net/cpsw.txt b/Documentation/devicetree/bindings/net/cpsw.txt
index 4108936..b3acebe 100644 (file)
--- a/Documentation/devicetree/bindings/net/cpsw.txt
+++ b/Documentation/devicetree/bindings/net/cpsw.txt
@@ -19,6 +19,10 @@ Required properties:
 - slaves               : Specifies number for slaves
 - active_slave         : Specifies the slave to use for time stamping,
                          ethtool and SIOCGMIIPHY
+- cpsw-phy-sel         : Specifies the phandle to the CPSW phy mode selection
+                         device. See also cpsw-phy-sel.txt for it's binding.
+                         Note that in legacy cases cpsw-phy-sel may be
+                         a child device instead of a phandle.
 
 Optional properties:
 - ti,hwmods            : Must be "cpgmac0"
@@ -75,6 +79,7 @@ Examples:
                cpts_clock_mult = <0x80000000>;
                cpts_clock_shift = <29>;
                syscon = <&cm>;
+               cpsw-phy-sel = <&phy_sel>;
                cpsw_emac0: slave@0 {
                        phy_id = <&davinci_mdio>, <0>;
                        phy-mode = "rgmii-txid";
@@ -103,6 +108,7 @@ Examples:
                cpts_clock_mult = <0x80000000>;
                cpts_clock_shift = <29>;
                syscon = <&cm>;
+               cpsw-phy-sel = <&phy_sel>;
                cpsw_emac0: slave@0 {
                        phy_id = <&davinci_mdio>, <0>;
                        phy-mode = "rgmii-txid";