serial:st-asc: Add ST ASC driver.

This patch adds support to ASC (asynchronous serial controller)
driver, which is basically a standard serial driver. This IP is common
across all the ST parts for settop box platforms.

ASC is embedded in ST COMMS IP block. It supports Rx & Tx functionality.
It support all industry standard baud rates.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@st.com>
CC: Stephen Gallimore <stephen.gallimore@st.com>
CC: Stuart Menefy <stuart.menefy@st.com>
CC: Arnd Bergmann <arnd@arndb.de>
CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 18 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/tty/serial/st-asc.txt b/Documentation/devicetree/bindings/tty/serial/st-asc.txt
new file mode 100644
index 000000000000..75d877f5968f
--- /dev/null
+++ b/Documentation/devicetree/bindings/tty/serial/st-asc.txt
@@ -0,0 +1,18 @@
+*st-asc(Serial Port)
+
+Required properties:
+- compatible : Should be "st,asc".
+- reg, reg-names, interrupts, interrupt-names   : Standard way to define device
+                        resources with names. look in
+                        Documentation/devicetree/bindings/resource-names.txt
+
+Optional properties:
+- st,hw-flow-ctrl       bool flag to enable hardware flow control.
+- st,force-m1           bool flat to force asc to be in Mode-1 recommeded
+                        for high bit rates (above 19.2K)
+Example:
+serial@fe440000{
+    compatible    = "st,asc";
+    reg         = <0xfe440000 0x2c>;
+    interrupts     =  <0 209 0>;
+};