diff options
| author | Lukas Wunner <lukas@wunner.de> | 2020-02-28 14:31:02 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-03-07 09:52:01 +0100 |
| commit | fe7f0fa43cef191a6d17bedf90bacce806c58eba (patch) | |
| tree | 2be63355f6c96c566f7031080c76c419c741df05 /drivers | |
| parent | f45709df7731ad36306a28a3e1af7309d55c35f5 (diff) | |
serial: 8250: Support rs485 devicetree properties
Retrieve rs485 devicetree properties on registration of 8250 ports in
case they are attached to an rs485 transceiver.
If the property "linux,rs485-enabled-at-boot-time" is present, invoke
the ->rs485_config() callback to immediately deassert RTS, thereby
ceasing control of the bus.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Giulio Benetti <giulio.benetti@micronovasrl.com>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/5908ea89b7f9da54872d6634b606d83db032297a.1582895077.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/tty/serial/8250/8250_core.c | 4 | ||||
| -rw-r--r-- | drivers/tty/serial/8250/8250_port.c | 3 |
2 files changed, 6 insertions, 1 deletions
diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c index f2a33c9082a6..9a1d09fbb836 100644 --- a/drivers/tty/serial/8250/8250_core.c +++ b/drivers/tty/serial/8250/8250_core.c @@ -1013,8 +1013,10 @@ int serial8250_register_8250_port(struct uart_8250_port *up) if (uart->port.fifosize && !uart->tx_loadsz) uart->tx_loadsz = uart->port.fifosize; - if (up->port.dev) + if (up->port.dev) { uart->port.dev = up->port.dev; + uart_get_rs485_mode(uart->port.dev, &uart->port.rs485); + } if (up->port.flags & UPF_FIXED_TYPE) uart->port.type = up->port.type; diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c index a8f4cedde4dc..40efcea8c6e7 100644 --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -2989,6 +2989,9 @@ static void serial8250_config_port(struct uart_port *port, int flags) if (flags & UART_CONFIG_TYPE) autoconfig(up); + if (port->rs485.flags & SER_RS485_ENABLED) + port->rs485_config(port, &port->rs485); + /* if access method is AU, it is a 16550 with a quirk */ if (port->type == PORT_16550A && port->iotype == UPIO_AU) up->bugs |= UART_BUG_NOMSR; |