[PATCH v4 2/9] dt-bindings: serial/rs485: make rs485-rts-delay optional
Uwe Kleine-König
u.kleine-koenig at pengutronix.de
Tue Jul 18 03:59:41 PDT 2017
There are a few device trees that specify one of the already optional
properties without also having the up to now required property
rs485-rts-delay. Additionally there is no technical reason to require
rs485-rts-delay and that's also what most drivers implement.
So give existing users and implementers a blessing and document
rs485-rts-delay as optional.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig at pengutronix.de>
Acked-by: Rob Herring <robh at kernel.org>
---
Documentation/devicetree/bindings/serial/rs485.txt | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/Documentation/devicetree/bindings/serial/rs485.txt b/Documentation/devicetree/bindings/serial/rs485.txt
index 32b1fa1f2a5b..b8415936dfdb 100644
--- a/Documentation/devicetree/bindings/serial/rs485.txt
+++ b/Documentation/devicetree/bindings/serial/rs485.txt
@@ -5,14 +5,13 @@ the built-in half-duplex mode.
The properties described hereafter shall be given to a half-duplex capable
UART node.
-Required properties:
+Optional properties:
- rs485-rts-delay: prop-encoded-array <a b> where:
* a is the delay between rts signal and beginning of data sent in milliseconds.
it corresponds to the delay before sending data.
* b is the delay between end of data sent and rts signal in milliseconds
it corresponds to the delay after sending data and actual release of the line.
-
-Optional properties:
+ If this property is not specified, <0 0> is assumed.
- linux,rs485-enabled-at-boot-time: empty property telling to enable the rs485
feature at boot time. It can be disabled later with proper ioctl.
- rs485-rx-during-tx: empty property that enables the receiving of data even
--
2.11.0
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