michaelh/zephyr
1
0
Fork 0
Code Releases Activity

drivers: uart: Add support for st single wire mode

Browse source 
An additional devicetree poperty `single-wire` is added
to uart and usart bindings of stm32. The driver checks this value
during initialization and enables the single wire mode when set.

Signed-off-by: Jonathan Hahn <Jonathan.Hahn@t-online.de>
This commit is contained in:
Jonathan Hahn 2022-01-01 23:41:19 +01:00 • committed by Carles Cufí
commit 32f9dcf328
4 changed files with 26 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

6
drivers/serial/uart_stm32.c
View file

@ -1585,6 +1585,11 @@ static int uart_stm32_init(const struct device *dev)
/* Set the default baudrate */ /* Set the default baudrate */
uart_stm32_set_baudrate(dev, data->baud_rate); uart_stm32_set_baudrate(dev, data->baud_rate);
/* Enable the single wire / half-duplex mode */
if (config->single_wire) {
LL_USART_EnableHalfDuplex(UartInstance);
}
LL_USART_Enable(UartInstance); LL_USART_Enable(UartInstance);
#ifdef USART_ISR_TEACK #ifdef USART_ISR_TEACK
@ -1701,6 +1706,7 @@ static const struct uart_stm32_config uart_stm32_cfg_##index = { \
.hw_flow_control = DT_INST_PROP(index, hw_flow_control), \ .hw_flow_control = DT_INST_PROP(index, hw_flow_control), \
.parity = DT_INST_ENUM_IDX_OR(index, parity, UART_CFG_PARITY_NONE), \ .parity = DT_INST_ENUM_IDX_OR(index, parity, UART_CFG_PARITY_NONE), \
.pcfg = PINCTRL_DT_INST_DEV_CONFIG_GET(index), \ .pcfg = PINCTRL_DT_INST_DEV_CONFIG_GET(index), \
.single_wire = DT_INST_PROP_OR(index, single_wire, false), \
STM32_UART_POLL_IRQ_HANDLER_FUNC(index) \ STM32_UART_POLL_IRQ_HANDLER_FUNC(index) \
}; \ }; \
\ \

2
drivers/serial/uart_stm32.h
View file

@ -23,6 +23,8 @@ struct uart_stm32_config {
bool hw_flow_control; bool hw_flow_control;
/* initial parity, 0 for none, 1 for odd, 2 for even */ /* initial parity, 0 for none, 1 for odd, 2 for even */
int parity; int parity;
/* switch to enable single wire / half duplex feature */
bool single_wire;
const struct pinctrl_dev_config *pcfg; const struct pinctrl_dev_config *pcfg;
#if defined(CONFIG_PM) \ #if defined(CONFIG_PM) \
&& !defined(CONFIG_UART_INTERRUPT_DRIVEN) \ && !defined(CONFIG_UART_INTERRUPT_DRIVEN) \

9
dts/bindings/serial/st,stm32-uart.yaml
View file

@ -11,6 +11,15 @@ properties:
interrupts: interrupts:
required: true required: true
single-wire:
type: boolean
required: false
description: |
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.
pinctrl-0: pinctrl-0:
required: true required: true

9
dts/bindings/serial/st,stm32-usart.yaml
View file

@ -11,6 +11,15 @@ properties:
interrupts: interrupts:
required: true required: true
single-wire:
type: boolean
required: false
description: |
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.
pinctrl-0: pinctrl-0:
required: true required: true