dt-bindings: mdio: Clarify binding document

[karo-tx-linux.git] / Documentation / devicetree / bindings / net / mdio.txt

diff --git a/Documentation/devicetree/bindings/net/mdio.txt b/Documentation/devicetree/bindings/net/mdio.txt
index 4ffbbacebda1b9029fb229af3ae5ac23873a6124..96a53f89aa6e2fa7f9a0d4c6c3b18d03a3b75994 100644 (file)
--- a/Documentation/devicetree/bindings/net/mdio.txt
+++ b/Documentation/devicetree/bindings/net/mdio.txt
@@ -3,13 +3,17 @@ Common MDIO bus properties.
 These are generic properties that can apply to any MDIO bus.
 
 Optional properties:
-- reset-gpios: List of one or more GPIOs that control the RESET lines
-  of the PHYs on that MDIO bus.
-- reset-delay-us: RESET pulse width in microseconds as per PHY datasheet.
+- reset-gpios: One GPIO that control the RESET lines of all PHYs on that MDIO
+  bus.
+- reset-delay-us: RESET pulse width in microseconds.
 
 A list of child nodes, one per device on the bus is expected. These
 should follow the generic phy.txt, or a device specific binding document.
 
+The 'reset-delay-us' indicates the RESET signal pulse width in microseconds and
+applies to all PHY devices. It must therefore be appropriately determined based
+on all PHY requirements (maximum value of all per-PHY RESET pulse widths).
+
 Example :
 This example shows these optional properties, plus other properties
 required for the TI Davinci MDIO driver.
@@ -21,7 +25,7 @@ required for the TI Davinci MDIO driver.
                #size-cells = <0>;
 
                reset-gpios = <&gpio2 5 GPIO_ACTIVE_LOW>;
-               reset-delay-us = <2>;   /* PHY datasheet states 1us min */
+               reset-delay-us = <2>;
 
                ethphy0: ethernet-phy@1 {
                        reg = <1>;