mirror of
https://github.com/torvalds/linux.git
synced 2026-04-18 14:53:58 -04:00
103dcf2ea2
Add polarity property for receiver enable. Some UARTs have separate enable pins for tx (RTS or DE) and rx (RE). As most RS485 transceivers have !RE pin, the default is active low in contrast to rs485-rts-active-low that defaults to active high. Cc: devicetree@vger.kernel.org Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20220426122448.38997-4-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
57 lines
1.8 KiB
YAML
57 lines
1.8 KiB
YAML
# 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 Bindings
|
|
|
|
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: 1000
|
|
- 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: 1000
|
|
|
|
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
|
|
|
|
additionalProperties: true
|
|
|
|
...
|