[PATCH net-next 1/2] dt-bindings: net: dsa: microchip: Add strap description

Bastien Curutchet posted 2 patches 8 hours ago
[PATCH net-next 1/2] dt-bindings: net: dsa: microchip: Add strap description
Posted by Bastien Curutchet 8 hours ago
At reset, some KSZ switches use strap-based configuration. If the
required pull-ups/pull-downs are missing (by mistake or by design to
save power) the pins may float and the configuration can go wrong.

Add a strap description that can be used by the driver to drive the
strap pins during reset. It consists of a 'reset' pinmux configuration
and a set of strap GPIOs.
Since the pins used and the nature of the configuration differ from one
KSZ switch to another, GPIO names aren't used.

Signed-off-by: Bastien Curutchet (Schneider Electric) <bastien.curutchet@bootlin.com>
---
 Documentation/devicetree/bindings/net/dsa/microchip,ksz.yaml | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/Documentation/devicetree/bindings/net/dsa/microchip,ksz.yaml b/Documentation/devicetree/bindings/net/dsa/microchip,ksz.yaml
index eb4607460db7f32a4dffd416e44b61c2674f731e..f40a5e3cd0e4d39c809a1fb6697bc3bc64f35fec 100644
--- a/Documentation/devicetree/bindings/net/dsa/microchip,ksz.yaml
+++ b/Documentation/devicetree/bindings/net/dsa/microchip,ksz.yaml
@@ -37,6 +37,13 @@ properties:
       - microchip,ksz8567
       - microchip,lan9646
 
+  pinctrl-names:
+    items:
+      - const: default
+      - const: reset
+        description:
+          Used during reset for strap configuration.
+
   reset-gpios:
     description:
       Should be a gpio specifier for a reset line.
@@ -80,6 +87,11 @@ properties:
     enum: [2000, 4000, 8000, 12000, 16000, 20000, 24000, 28000]
     default: 8000
 
+  strap-gpios:
+    description:
+      Strap pins to drive during reset. For KSZ8463, the first GPIO drives the
+      RXDO line, the second one drives the RXD1 line.
+
   interrupts:
     maxItems: 1
 

-- 
2.51.0