tty: Add termiox

We need a way to describe the various additional modes and flow control
features that random weird hardware shows up and software such as wine
wants to emulate as Windows supports them.

TCGETX/TCSETX and the termiox ioctl are a SYS5 extension that we might as
well adopt. This patches adds the structures and the basic ioctl interfaces
when the TCGETX etc defines are added for an architecture. Drivers wishing
to use this stuff need to add new methods.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/termios.h b/include/linux/termios.h
index 4786628..2acd0c1 100644
--- a/include/linux/termios.h
+++ b/include/linux/termios.h
@@ -4,4 +4,19 @@
 #include <linux/types.h>
 #include <asm/termios.h>
 
+#define NFF	5
+
+struct termiox
+{
+	__u16	x_hflag;
+	__u16	x_cflag;
+	__u16	x_rflag[NFF];
+	__u16	x_sflag;
+};
+
+#define	RTSXOFF		0x0001		/* RTS flow control on input */
+#define	CTSXON		0x0002		/* CTS flow control on output */
+#define	DTRXOFF		0x0004		/* DTR flow control on input */
+#define DSRXON		0x0008		/* DCD flow control on output */
+
 #endif