Some transceivers need a configuration step (for example, pulling
a standby line low) for them to start sending messages. Instead of a
parent child relationship, the transceiver can be implemented as a
phy with the configuration done in the phy driver. The bitrate
limitations can then be obtained by the driver using said phy
node.
Document the above implementation.
Signed-off-by: Faiz Abbas <faiz_abbas@xxxxxx>
---
.../devicetree/bindings/net/can/m_can.txt | 24 ++++++++++++-------
1 file changed, 16 insertions(+), 8 deletions(-)
diff --git a/Documentation/devicetree/bindings/net/can/m_can.txt b/Documentation/devicetree/bindings/net/can/m_can.txt
index ed614383af9c..c11548e74278 100644
--- a/Documentation/devicetree/bindings/net/can/m_can.txt
+++ b/Documentation/devicetree/bindings/net/can/m_can.txt
@@ -42,12 +42,14 @@ Required properties:
Please refer to 2.4.1 Message RAM Configuration in
Bosch M_CAN user manual for details.
+Optional properties:
+- phy-names : must be "can_transceiver". The transceiver
+ typically limits the maximum bitrate of the
+ system. The phy node is used to discover this
+ limitation.
+- phys : phandle to the transceiver implemented as a phy
+ node.
-Optional Subnode:
-- can-transceiver : Can-transceiver subnode describing maximum speed
- that can be used for CAN/CAN-FD modes. See
- Documentation/devicetree/bindings/net/can/can-transceiver.txt
- for details.
Example:
SoC dtsi:
m_can1: can@20e8000 {
@@ -64,12 +66,18 @@ m_can1: can@20e8000 {
};
Board dts:
+
&m_can1 {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_m_can1>;
status = "enabled";
+ phy-names = "can_transceiver";
+ phys = <&transceiver1>;
+};
- can-transceiver {
- max-bitrate = <5000000>;
- };
+transceiver1: can-transceiver {
+ compatible = "simple-phy";
+ max-bitrate = <5000000>;
+ pwr-supply = <&transceiver1_fixed>;
+ #phy-cells = <0>;
};
--
2.18.0
