drm: sti: add GDP layer

Generic Display Pipeline are one of the compositor input sub-devices.
GDP are dedicated to graphic input like RGB plans.
GDP is part of Compositor hardware block which will be introduce later.

A sti_layer structure is used to abstract GDP calls from Compositor.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Reviewed-by: Rob Clark <robdclark@gmail.com>

drivers/gpu/drm/sti/sti_gdp.h

@@ -0,0 +1,16 @@
+/*
+ * Copyright (C) STMicroelectronics SA 2014
+ * Authors: Benjamin Gaignard <benjamin.gaignard@st.com>
+ *          Fabien Dessenne <fabien.dessenne@st.com>
+ *          for STMicroelectronics.
+ * License terms:  GNU General Public License (GPL), version 2
+ */
+
+#ifndef _STI_GDP_H_
+#define _STI_GDP_H_
+
+#include <linux/types.h>
+
+struct sti_layer *sti_gdp_create(struct device *dev, int id);
+
+#endif