[RFC PATCH net-next 1/2] dt-bindings: net: Add documentation for Half duplex support.

[MD Danish Anwar]

In order to support half-duplex operation at 10M and 100M link speeds, the
PHY collision detection signal (COL) should be routed to ICSSG
GPIO pin (PRGx_PRU0/1_GPI10) so that firmware can detect collision signal
and apply the CSMA/CD algorithm applicable for half duplex operation. A DT
property, "ti,half-duplex-capable" is introduced for this purpose. If
board has PHY COL pin conencted to PRGx_PRU1_GPIO10, this DT property can
be added to eth node of ICSSG, MII port to support half duplex operation at
that port.

Signed-off-by: MD Danish Anwar <danishanwar@xxxxxx>
---
 Documentation/devicetree/bindings/net/ti,icssg-prueth.yaml | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/Documentation/devicetree/bindings/net/ti,icssg-prueth.yaml b/Documentation/devicetree/bindings/net/ti,icssg-prueth.yaml
index 13371159515a..59da9aeaee7e 100644
--- a/Documentation/devicetree/bindings/net/ti,icssg-prueth.yaml
+++ b/Documentation/devicetree/bindings/net/ti,icssg-prueth.yaml
@@ -107,6 +107,13 @@ properties:
               phandle to system controller node and register offset
               to ICSSG control register for RGMII transmit delay
 
+          ti,half-duplex-capable:
+            type: boolean
+            description:
+              Enable half duplex operation on ICSSG MII port. This requires
+              PHY output pin (COL) to be routed to ICSSG GPIO pin
+              (PRGx_PRU0/1_GPIO10) as input.
+
         required:
           - reg
     anyOf:
-- 
2.34.1