ARM: dts: Nokia N9: add support for up/down keys in the dts

This adds support for volume up/down keys in the dts.
Signed-off-by: NPavel Machek <pavel@ucw.cz>
Reviewed-by: NSebastian Reichel <sebastian.reichel@collabora.co.uk>
Signed-off-by: NTony Lindgren <tony@atomide.com>

arch/arm/boot/dts/omap3-n9.dts

@@ -11,6 +11,7 @@
 /dts-v1/;
 
 #include "omap3-n950-n9.dtsi"
+#include <dt-bindings/input/input.h>
 
 / {
 	model = "Nokia N9";
@@ -72,3 +73,9 @@
 	st,max-limit-y = <46>;
 	st,max-limit-z = <46>;
 };
+
+&twl_keypad {
+	linux,keymap = < MATRIX_KEY(6, 8, KEY_VOLUMEUP)
+			 MATRIX_KEY(7, 8, KEY_VOLUMEDOWN)
+			 >;
+};