Current pattern in the linux kernel is that every new serial driver adds one or more new PORT_ definitions because uart_ops::config_port() callback documentation prescribes setting port->type according to the type of port found, or to PORT_UNKNOWN if no port was detected. When the specific type of the port is not important to the userspace there's no need for a unique PORT_ value, but so far there's no suitable identifier for that case. Provide generic port type identifier other than PORT_UNKNOWN for ports which type is not important to userspace. Suggested-by: Arnd Bergmann <arnd@xxxxxxxx> Suggested-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Max Filippov <jcmvbkbc@xxxxxxxxx> --- include/uapi/linux/serial.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/include/uapi/linux/serial.h b/include/uapi/linux/serial.h index 53bc1af67a41..070e50cf9e1e 100644 --- a/include/uapi/linux/serial.h +++ b/include/uapi/linux/serial.h @@ -47,6 +47,8 @@ struct serial_struct { /* * These are the supported serial types. */ +/* Generic type identifier for ports which type is not important to userspace. */ +#define PORT_ANY (-1) #define PORT_UNKNOWN 0 #define PORT_8250 1 #define PORT_16450 2 -- 2.30.2