xref: /linux/Documentation/devicetree/bindings/serial/rs485.yaml (revision 0c01b20fb50ba63c03841aa83070dc59c3b1b02f)
1d50f974cSBenjamin Gaignard# SPDX-License-Identifier: GPL-2.0
2d50f974cSBenjamin Gaignard%YAML 1.2
3d50f974cSBenjamin Gaignard---
4d50f974cSBenjamin Gaignard$id: http://devicetree.org/schemas/serial/rs485.yaml#
5d50f974cSBenjamin Gaignard$schema: http://devicetree.org/meta-schemas/core.yaml#
6d50f974cSBenjamin Gaignard
784e85359SKrzysztof Kozlowskititle: RS485 serial communications
8d50f974cSBenjamin Gaignard
99f60a65bSRob Herringdescription: The RTS signal is capable of automatically controlling line
109f60a65bSRob Herring  direction for the built-in half-duplex mode. The properties described
119f60a65bSRob Herring  hereafter shall be given to a half-duplex capable UART node.
12d50f974cSBenjamin Gaignard
13d50f974cSBenjamin Gaignardmaintainers:
14d50f974cSBenjamin Gaignard  - Rob Herring <robh@kernel.org>
15d50f974cSBenjamin Gaignard
16d50f974cSBenjamin Gaignardproperties:
17d50f974cSBenjamin Gaignard  rs485-rts-delay:
18d50f974cSBenjamin Gaignard    description: prop-encoded-array <a b>
193d21a460SRob Herring    $ref: /schemas/types.yaml#/definitions/uint32-array
20d50f974cSBenjamin Gaignard    items:
213d21a460SRob Herring      items:
223d21a460SRob Herring        - description: Delay between rts signal and beginning of data sent in
233d21a460SRob Herring            milliseconds. It corresponds to the delay before sending data.
24d50f974cSBenjamin Gaignard          default: 0
25885dcb08SLino Sanfilippo          maximum: 100
263d21a460SRob Herring        - description: Delay between end of data sent and rts signal in milliseconds.
273d21a460SRob Herring            It corresponds to the delay after sending data and actual release
283d21a460SRob Herring            of the line.
29d50f974cSBenjamin Gaignard          default: 0
30885dcb08SLino Sanfilippo          maximum: 100
31d50f974cSBenjamin Gaignard
32*0c01b20fSFrancesco Dolcini  rs485-rts-active-high:
33*0c01b20fSFrancesco Dolcini    description: drive RTS high when sending (this is the default).
34*0c01b20fSFrancesco Dolcini    $ref: /schemas/types.yaml#/definitions/flag
35*0c01b20fSFrancesco Dolcini
36d50f974cSBenjamin Gaignard  rs485-rts-active-low:
37d50f974cSBenjamin Gaignard    description: drive RTS low when sending (default is high).
38d50f974cSBenjamin Gaignard    $ref: /schemas/types.yaml#/definitions/flag
39d50f974cSBenjamin Gaignard
40103dcf2eSIlpo Järvinen  rs485-rx-active-high:
41103dcf2eSIlpo Järvinen    description: Polarity of receiver enable signal (when separate from RTS).
42103dcf2eSIlpo Järvinen      True indicates active high (default is low).
43103dcf2eSIlpo Järvinen    $ref: /schemas/types.yaml#/definitions/flag
44103dcf2eSIlpo Järvinen
45d50f974cSBenjamin Gaignard  linux,rs485-enabled-at-boot-time:
469f60a65bSRob Herring    description: enables the rs485 feature at boot time. It can be disabled
479f60a65bSRob Herring      later with proper ioctl.
48d50f974cSBenjamin Gaignard    $ref: /schemas/types.yaml#/definitions/flag
49d50f974cSBenjamin Gaignard
50d50f974cSBenjamin Gaignard  rs485-rx-during-tx:
51d50f974cSBenjamin Gaignard    description: enables the receiving of data even while sending data.
52d50f974cSBenjamin Gaignard    $ref: /schemas/types.yaml#/definitions/flag
5301c38ecfSLukas Wunner
5401c38ecfSLukas Wunner  rs485-term-gpios:
5501c38ecfSLukas Wunner    description: GPIO pin to enable RS485 bus termination.
5601c38ecfSLukas Wunner    maxItems: 1
576a0e321eSRob Herring
5845c1d967SChristoph Niedermaier  rs485-rx-during-tx-gpios:
5945c1d967SChristoph Niedermaier    description: Output GPIO pin that sets the state of rs485-rx-during-tx. This
6045c1d967SChristoph Niedermaier      signal can be used to control the RX part of an RS485 transceiver. Thereby
6145c1d967SChristoph Niedermaier      the active state enables RX during TX.
6245c1d967SChristoph Niedermaier    maxItems: 1
6345c1d967SChristoph Niedermaier
646a0e321eSRob HerringadditionalProperties: true
656a0e321eSRob Herring
669f60a65bSRob Herring...
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