diff options
| author | Christoph Niedermaier <cniedermaier@dh-electronics.com> | 2022-12-02 13:41:25 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-01-19 18:01:35 +0300 |
| commit | 163f080eb717d237f02d9a8c179b07ed31fdd6ad (patch) | |
| tree | 89c8528fa505f8e9ad81efc982a57f6016c1976b /drivers/tty | |
| parent | 45c1d967a762ad8df7e1ccfa4a22dd77e2efa3b8 (diff) | |
| download | linux-163f080eb717d237f02d9a8c179b07ed31fdd6ad.tar.xz | |
serial: core: Add option to output RS485 RX_DURING_TX state via GPIO
This patch provides a generic GPIO variable for outputting the state
of RS485 RX_DURING_TX. The GPIO is defined by the devicetree property
"rs485-rx-during-tx-gpios". To use it in a low level serial driver,
the evaluation of this variable must be implemented there accordingly.
Signed-off-by: Christoph Niedermaier <cniedermaier@dh-electronics.com>
Link: https://lore.kernel.org/r/20221202104127.122761-2-cniedermaier@dh-electronics.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/serial/serial_core.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index b9fbbee598b8..867f2675caca 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -3410,6 +3410,7 @@ int uart_get_rs485_mode(struct uart_port *port) struct device *dev = port->dev; u32 rs485_delay[2]; int ret; + int rx_during_tx_gpio_flag; ret = device_property_read_u32_array(dev, "rs485-rts-delay", rs485_delay, 2); @@ -3458,6 +3459,17 @@ int uart_get_rs485_mode(struct uart_port *port) if (port->rs485_term_gpio) port->rs485_supported.flags |= SER_RS485_TERMINATE_BUS; + rx_during_tx_gpio_flag = (rs485conf->flags & SER_RS485_RX_DURING_TX) ? + GPIOD_OUT_HIGH : GPIOD_OUT_LOW; + port->rs485_rx_during_tx_gpio = devm_gpiod_get_optional(dev, + "rs485-rx-during-tx", + rx_during_tx_gpio_flag); + if (IS_ERR(port->rs485_rx_during_tx_gpio)) { + ret = PTR_ERR(port->rs485_rx_during_tx_gpio); + port->rs485_rx_during_tx_gpio = NULL; + return dev_err_probe(dev, ret, "Cannot get rs485-rx-during-tx-gpios\n"); + } + return 0; } EXPORT_SYMBOL_GPL(uart_get_rs485_mode); |