Manikanta Guntupalli schreef op 2023-10-24 16:48:
Add optional gpio property to uartps node and reference to rs485.yaml
On Xilinx/AMD Kria SOM KD240 board rs485 connects via TI ISOW1432
Transceiver device, where one GPIO is used for driving DE/RE signals.
With rs485 half duplex configuration, DE and RE are shorted to each
other,
and at a time, any node acts as either a driver or a receiver.
Here,
DE - Driver enable. If pin is floating, driver is disabled.
RE - Receiver enable. If pin is floating, receiver buffer is disabled.
For more deatils, please find below link which contains Transceiver
device(ISOW1432) datasheet
https://www.ti.com/lit/ds/symlink/isow1432.pdf?ts=1682607122706&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FISOW1432%252Fpart-details%252FISOW1432DFMR%253FkeyMatch%253DISOW1432DFMR%2526tisearch%253Dsearch-everything%2526usecase%253DOPN
rts-gpios is optional property, because it is not required
for uart console node.
Signed-off-by: Manikanta Guntupalli <manikanta.guntupalli@xxxxxxx>
---
Changes for V2:
Modify optional gpio name to xlnx,phy-ctrl-gpios.
Update commit description.
Changes for V3:
Modify optional gpio name to rts-gpios.
Update commit description.
---
Documentation/devicetree/bindings/serial/cdns,uart.yaml | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/Documentation/devicetree/bindings/serial/cdns,uart.yaml
b/Documentation/devicetree/bindings/serial/cdns,uart.yaml
index e35ad1109efc..7ee305f9a45f 100644
--- a/Documentation/devicetree/bindings/serial/cdns,uart.yaml
+++ b/Documentation/devicetree/bindings/serial/cdns,uart.yaml
@@ -46,6 +46,11 @@ properties:
power-domains:
maxItems: 1
+ rts-gpios:
+ description: Optional GPIO to control transmit/receive on RS485
phy
+ in halfduplex mode.
+ maxItems: 1
+
Why would this be related to RS485? A user could also have a need for a
gpio instead of the native pin to be used as normal rts.
All RS485 references can be removed.
required:
- compatible
- reg
@@ -55,6 +60,7 @@ required:
allOf:
- $ref: serial.yaml#
+ - $ref: rs485.yaml#
- if:
properties:
compatible:
Maarten
