On Sat, 18 Aug 2012 23:44:29 -0700
Greg KH [off-list ref] wrote:

On Sun, Aug 19, 2012 at 02:27:12PM -0400, Huang Shijie wrote:

quoted

--- a/include/linux/tty.h
+++ b/include/linux/tty.h

@@ -43,6 +43,7 @@
 #include <linux/tty_driver.h>
 #include <linux/tty_ldisc.h>
 #include <linux/mutex.h>
+#include <linux/serial.h>
 
 
 

@@ -513,6 +514,12 @@ static inline struct tty_port *tty_port_get(struct tty_port *port)
 	return port;
 }
 
+/* If the cts flow control is enabled, return true. */
+static inline bool tty_port_cts_enabled(struct tty_port *port)
+{
+	return port->flags & ASYNC_CTS_FLOW;
+}
+

The fact that you have to add serial.h to this file kind of implies that
this function shouldn't be here, right?

How about serial.h instead?  Not all tty drivers are serial drivers :)

tty_port is tty generic so possibly if there is a generic helper the
flags and helper should likewise be this way.

As it stands at the moment ASYNC_CTS_FLOW is a convention a few drivers
use. So calling it tty_port_xxx is going to misleading.

Alan