st,stm32-usart

Vendor: STMicroelectronics

Description

These nodes are “uart” bus nodes.

STM32 USART

Properties

Properties not inherited from the base binding file.

Name

Type

Details

current-speed

int

Initial baud rate setting for UART

hw-flow-control

boolean

Set to enable RTS/CTS flow control at boot time

parity

string

Configures the parity of the adapter. Enumeration id 0 for none, 1 for odd
and 2 for even parity. Default to none if not specified.

Legal values: 'none', 'odd', 'even'

stop-bits

string

Sets the number of stop bits.

Legal values: '0_5', '1', '1_5', '2'

data-bits

int

Sets the number of data bits.

Legal values: 5, 6, 7, 8, 9

pinctrl-0

phandles

Pin configuration/s for the first state. Content is specific to the
selected pin controller driver implementation.

This property is required.

pinctrl-1

phandles

Pin configuration/s for the second state. See pinctrl-0.

pinctrl-2

phandles

Pin configuration/s for the third state. See pinctrl-0.

pinctrl-3

phandles

Pin configuration/s for the fourth state. See pinctrl-0.

pinctrl-4

phandles

Pin configuration/s for the fifth state. See pinctrl-0.

pinctrl-names

string-array

Names for the provided states. The number of names needs to match the
number of states.

This property is required.

resets

phandle-array

Reset information

This property is required.

reset-names

string-array

Name of each reset

single-wire

boolean

Enable the single wire half-duplex communication.
Using this mode, TX and RX lines are internally connected and
only TX pin is used afterwards and should be configured.
RX/TX conflicts must be handled on user side.

tx-rx-swap

boolean

Swap the TX and RX pins. Used in case of a cross wired connection.

tx-invert

boolean

Invert the binary logic of tx pin. When enabled, physical logic levels are inverted and
we use 1=Low, 0=High instead of 1=High, 0=Low.

rx-invert

boolean

Invert the binary logic of rx pin. When enabled, physical logic levels are inverted and
we use 1=Low, 0=High instead of 1=High, 0=Low.

wakeup-line

int

EXTI line number matching the device wakeup interrupt mask register.
This property is required on stm32 devices where the wakeup interrupt signal could be
configured masked at boot (sm32wl55 for instance), preventing the device to wakeup
the core from stop mode(s).
Valid range: 0 - 31

de-enable

boolean

Enable activating an external transeiver through the DE pin which must also be configured
using pinctrl.

de-assert-time

int

Defines the time between the activation of the DE signal and the beginning of the start bit.
It is expressed in 16th of a bit time.
Valid range: 0 - 31

de-deassert-time

int

Defines the time between the activation of the DE signal and the beginning of the start bit.
It is expressed in 16th of a bit time.
Valid range: 0 - 31

de-invert

boolean

Invert the binary logic of the de pin. When enabled, physical logic levels are inverted and
we use 1=Low, 0=High instead of 1=High, 0=Low.

fifo-enable

boolean

Enables transmit and receive FIFO using default FIFO configuration (typically threshold is
set to 1/8).
In TX, FIFO allows to work in burst mode, easing scheduling of loaded applications. It also
allows more reliable communication with UART devices sensitive to variation of inter-frames
delays.
In RX, FIFO reduces overrun occurrences.