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> --- Changes v1->v2: - move to the end of PORT_ definition list - rename to PORT_GENERIC include/uapi/linux/serial_core.h | 3 +++ 1 file changed, 3 insertions(+) diff --git a/include/uapi/linux/serial_core.h b/include/uapi/linux/serial_core.h index add349889d0a..0a5090e08657 100644 --- a/include/uapi/linux/serial_core.h +++ b/include/uapi/linux/serial_core.h @@ -245,4 +245,7 @@ /* Sunplus UART */ #define PORT_SUNPLUS 123 +/* Generic type identifier for ports which type is not important to userspace. */ +#define PORT_GENERIC (-1) + #endif /* _UAPILINUX_SERIAL_CORE_H */ -- 2.30.2