summaryrefslogtreecommitdiffstats
path: root/Documentation/devicetree/bindings/serial/rs485.yaml
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/devicetree/bindings/serial/rs485.yaml')
-rw-r--r--Documentation/devicetree/bindings/serial/rs485.yaml66
1 files changed, 66 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/serial/rs485.yaml b/Documentation/devicetree/bindings/serial/rs485.yaml
new file mode 100644
index 0000000000..9418fd66a8
--- /dev/null
+++ b/Documentation/devicetree/bindings/serial/rs485.yaml
@@ -0,0 +1,66 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/serial/rs485.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: RS485 serial communications
+
+description: The RTS signal is capable of automatically controlling line
+ direction for the built-in half-duplex mode. The properties described
+ hereafter shall be given to a half-duplex capable UART node.
+
+maintainers:
+ - Rob Herring <robh@kernel.org>
+
+properties:
+ rs485-rts-delay:
+ description: prop-encoded-array <a b>
+ $ref: /schemas/types.yaml#/definitions/uint32-array
+ items:
+ items:
+ - description: Delay between rts signal and beginning of data sent in
+ milliseconds. It corresponds to the delay before sending data.
+ default: 0
+ maximum: 100
+ - description: 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.
+ default: 0
+ maximum: 100
+
+ rs485-rts-active-high:
+ description: drive RTS high when sending (this is the default).
+ $ref: /schemas/types.yaml#/definitions/flag
+
+ rs485-rts-active-low:
+ description: drive RTS low when sending (default is high).
+ $ref: /schemas/types.yaml#/definitions/flag
+
+ rs485-rx-active-high:
+ description: Polarity of receiver enable signal (when separate from RTS).
+ True indicates active high (default is low).
+ $ref: /schemas/types.yaml#/definitions/flag
+
+ linux,rs485-enabled-at-boot-time:
+ description: enables the rs485 feature at boot time. It can be disabled
+ later with proper ioctl.
+ $ref: /schemas/types.yaml#/definitions/flag
+
+ rs485-rx-during-tx:
+ description: enables the receiving of data even while sending data.
+ $ref: /schemas/types.yaml#/definitions/flag
+
+ rs485-term-gpios:
+ description: GPIO pin to enable RS485 bus termination.
+ maxItems: 1
+
+ rs485-rx-during-tx-gpios:
+ description: Output GPIO pin that sets the state of rs485-rx-during-tx. This
+ signal can be used to control the RX part of an RS485 transceiver. Thereby
+ the active state enables RX during TX.
+ maxItems: 1
+
+additionalProperties: true
+
+...