drivers tty: add okl4_vtty driver

Adds a driver which provides console and TTY using the OKL4
hypervisor pipe IPC facility.

Change-Id: Iccbb9eda626fd90d3cc6494c490e13d51edfe42a
Signed-off-by: Carl van Schaik <carl@cog.systems>
Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Signed-off-by: Ashok Kundurthi <askund@codeaurora.org>
diff --git a/drivers/tty/Kconfig b/drivers/tty/Kconfig
index 741e966..53e3186 100644
--- a/drivers/tty/Kconfig
+++ b/drivers/tty/Kconfig
@@ -458,4 +458,21 @@
 	help
 	  FDC channel number to use for KGDB.
 
+config OKL4_VTTY
+	bool "Virtual TTY on the OKL4 Microvisor"
+	depends on OKL4_GUEST
+	select TTY_FLUSH_LOCAL_ECHO
+	default y
+	---help---
+	  This device provides character-level read-write access
+	  to the virtual console, usually connected to a serial-server which
+	  multiplexes output on a physical UART.
+
+config OKL4_VTTY_CONSOLE
+	bool "Console on OKL4 VTTY"
+	depends on OKL4_VTTY
+	default y
+	help
+	  Console support for OKL4 Microvisor virtual ttys.
+
 endif # TTY