1 # SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
4 $id: "http://devicetree.org/schemas/serial/serial.yaml#"
5 $schema: "http://devicetree.org/meta-schemas/core.yaml#"
7 title: Serial Interface Generic DT Bindings
10 - Rob Herring <robh@kernel.org>
11 - Greg Kroah-Hartman <gregkh@linuxfoundation.org>
14 This document lists a set of generic properties for describing UARTs in a
15 device tree. Whether these properties apply to a particular device depends
16 on the DT bindings for the actual device.
18 Each enabled UART may have an optional "serialN" alias in the "aliases" node,
19 where N is the port number (non-negative decimal integer) as printed on the
20 label next to the physical port.
24 pattern: "^serial(@.*)?$"
29 Must contain a GPIO specifier, referring to the GPIO pin to be used as
35 Must contain a GPIO specifier, referring to the GPIO pin to be used as
41 Must contain a GPIO specifier, referring to the GPIO pin to be used as
47 Must contain a GPIO specifier, referring to the GPIO pin to be used as
53 Must contain a GPIO specifier, referring to the GPIO pin to be used as
59 Must contain a GPIO specifier, referring to the GPIO pin to be used as
63 $ref: /schemas/types.yaml#/definitions/flag
65 The presence of this property indicates that the UART has dedicated lines
66 for RTS/CTS hardware flow control, and that they are available for use
67 (wired and enabled by pinmux configuration). This depends on both the
68 UART hardware and the board wiring.
72 description: RX and TX pins are swapped.
76 description: CTS and RTS pins are swapped.
79 $ref: /schemas/types.yaml#/definitions/uint32
81 RX FIFO threshold configuration (in bytes).
84 $ref: /schemas/types.yaml#/definitions/uint32
86 TX FIFO threshold configuration (in bytes).
102 Serial attached devices shall be a child node of the host UART device
103 the slave device is attached to. It is expected that the attached
104 device is the only child node of the UART device. The slave device node
105 name shall reflect the generic type of device for the node.
110 Compatible of the device connected to the serial port.
113 $ref: /schemas/types.yaml#/definitions/uint32
115 The maximum baud rate the device operates at.
116 This should only be present if the maximum is less than the slave
117 device can support. For example, a particular board has some
118 signal quality issue or the host processor can't support higher
122 $ref: /schemas/types.yaml#/definitions/uint32
124 The current baud rate the device operates at.
125 This should only be present in case a driver has no chance to know
126 the baud rate of the slave device.
128 * device supports auto-baud
129 * the rate is setup by a bootloader and there is no way to reset
131 * device baud rate is configured by its firmware but there is no
132 way to request the actual settings
137 additionalProperties: true
142 compatible = "ns16550a";
147 compatible = "brcm,bcm4330-bt";
148 interrupt-parent = <&gpio>;