[PATCH 2/6] net: arc_emac: add phy-reset-* are optional for device tree

[Caesar Wang <wxt@rock-chips.com>]

This patch adds the following property for arc_emac.

1) phy-reset-gpios:
The phy-reset-gpios is an optional property for arc emac device tree boot.
Change the binding document to match the driver code.

2) phy-reset-duration:
Different boards may require different phy reset duration. Add property
phy-reset-duration for device tree probe, so that the boards that need
a longer reset duration can specify it in their device tree.

3) phy-reset-active-high:
We need that for a custom hardware that needs the reverse reset
sequence.

Anyway, we can add the above property for arc emac.

Signed-off-by: Caesar Wang <wxt@rock-chips.com>
---

 Documentation/devicetree/bindings/net/arc_emac.txt | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/Documentation/devicetree/bindings/net/arc_emac.txt b/Documentation/devicetree/bindings/net/arc_emac.txt
index a1d71eb..6389b00 100644
--- a/Documentation/devicetree/bindings/net/arc_emac.txt
+++ b/Documentation/devicetree/bindings/net/arc_emac.txt
@@ -7,6 +7,16 @@ Required properties:
 - max-speed: see ethernet.txt file in the same directory.
 - phy: see ethernet.txt file in the same directory.
 
+Optional properties:
+- phy-reset-gpios : Should specify the gpio for phy reset
+- phy-reset-duration : Reset duration in milliseconds.  Should present
+  only if property "phy-reset-gpios" is available.  Missing the property
+  will have the duration be 1 millisecond.  Numbers greater than 1000 are
+  invalid and 1 millisecond will be used instead.
+- phy-reset-active-high : If present then the reset sequence using the GPIO
+  specified in the "phy-reset-gpios" property is reversed (H=reset state,
+  L=operation state).
+
 Clock handling:
 The clock frequency is needed to calculate and set polling period of EMAC.
 It must be provided by one of:
-- 
1.9.1