[PATCH v3 3/5] tty: Implement default fallback serial8250_rs485_config

Matwey V. Kornilov
2015-11-12T14:35:37Z

When 8250 driver doesn't have its own hardware RS485 support and doesn't
want to override rs485_config callback, then default
serial8250_rs485_config is used. It just stores supplied by user-space
config and sets SER_RS485_SOFTWARE

Signed-off-by: Matwey V. Kornilov <matwey@sai.msu.ru>
---
drivers/tty/serial/8250/8250_core.c | 3 ++-
drivers/tty/serial/8250/8250_port.c | 10 ++++++++++
2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
index 3912646..71fabb0 100644
--- a/drivers/tty/serial/8250/8250_core.c
+++ b/drivers/tty/serial/8250/8250_core.c
@@ -986,7 +986,6 @@ int serial8250_register_8250_port(struct uart_8250_port *up)
uart->capabilities = up->capabilities;
uart->port.throttle = up->port.throttle;
uart->port.unthrottle = up->port.unthrottle;
- uart->port.rs485_config = up->port.rs485_config;
uart->port.rs485 = up->port.rs485;
uart->dma = up->dma;

@@ -1025,6 +1024,8 @@ int serial8250_register_8250_port(struct uart_8250_port *up)
uart->port.pm = up->port.pm;
if (up->port.handle_break)
uart->port.handle_break = up->port.handle_break;
+ if (up->port.rs485_config)
+ uart->port.rs485_config = up->port.rs485_config;
if (up->dl_read)
uart->dl_read = up->dl_read;
if (up->dl_write)
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 52d82d2..067ef55 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -2735,6 +2735,14 @@ serial8250_type(struct uart_port *port)
return uart_config[type].name;
}

+static int serial8250_rs485_config(struct uart_port *port,
+ struct serial_rs485 *rs485)
+{
+ port->rs485 = *rs485;
+ port->rs485.flags |= SER_RS485_SOFTWARE;
+ return 0;
+}
+
static const struct uart_ops serial8250_pops = {
.tx_empty = serial8250_tx_empty,
.set_mctrl = serial8250_set_mctrl,
@@ -2797,6 +2805,8 @@ void serial8250_set_defaults(struct uart_8250_port *up)
if (!up->dma->rx_dma)
up->dma->rx_dma = serial8250_rx_dma;
}
+
+ up->port.rs485_config = serial8250_rs485_config;
}
EXPORT_SYMBOL_GPL(serial8250_set_defaults);

--
2.6.2