diff options
| author | Crescent CY Hsieh <crescentcy.hsieh@moxa.com> | 2023-12-01 10:15:54 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-01-04 18:20:36 +0300 |
| commit | 6056f20f27e99fb67582f299468328505f130e36 (patch) | |
| tree | b948b9d83163023c5e59a9948e54dcdb9d2fb492 /drivers/tty/serial | |
| parent | 76ac8e29855b06331d77a1d237a28ce97ac67a38 (diff) | |
| download | linux-6056f20f27e99fb67582f299468328505f130e36.tar.xz | |
tty: serial: Add RS422 flag to struct serial_rs485
Add "SER_RS485_MODE_RS422" flag to struct serial_rs485, so that serial
port can switch interface into RS422 if supported by using ioctl command
"TIOCSRS485".
By treating RS422 as a mode of RS485, which means while enabling RS422
there are two flags need to be set (SER_RS485_ENABLED and
SER_RS485_MODE_RS422), it would make things much easier. For example
some places that checks for "SER_RS485_ENABLED" won't need to be rewritten.
Signed-off-by: Crescent CY Hsieh <crescentcy.hsieh@moxa.com>
Link: https://lore.kernel.org/r/20231201071554.258607-3-crescentcy.hsieh@moxa.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial')
| -rw-r--r-- | drivers/tty/serial/serial_core.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index 1147fb1b39f2..d35371c076b2 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -1370,6 +1370,12 @@ static void uart_sanitize_serial_rs485(struct uart_port *port, struct serial_rs4 return; } + /* Clear other RS485 flags but SER_RS485_TERMINATE_BUS and return if enabling RS422 */ + if (rs485->flags & SER_RS485_MODE_RS422) { + rs485->flags &= (SER_RS485_ENABLED | SER_RS485_MODE_RS422 | SER_RS485_TERMINATE_BUS); + return; + } + /* Pick sane settings if the user hasn't */ if ((supported_flags & (SER_RS485_RTS_ON_SEND|SER_RS485_RTS_AFTER_SEND)) && !(rs485->flags & SER_RS485_RTS_ON_SEND) == |