OMAP: DSS2: OMAPFB: Add support for switching memory regions

Separate the memory region from the framebuffer device a little bit.
It's now possible to select the memory region used by the framebuffer
device using the new mem_idx parameter of omapfb_plane_info. If the
mem_idx is specified it will be interpreted as an index into the
memory regions array, if it's not specified the framebuffer's index is
used instead. So by default each framebuffer keeps using it's own
memory region which preserves backwards compatibility.

This allows cloning the same memory region to several overlays and yet
each overlay can be controlled independently since they can be
associated with separate framebuffer devices.

Signed-off-by: Ville Syrjälä <ville.syrjala@nokia.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@nokia.com>
diff --git a/include/linux/omapfb.h b/include/linux/omapfb.h
index 9bdd914..0ecf731 100644
--- a/include/linux/omapfb.h
+++ b/include/linux/omapfb.h
@@ -85,6 +85,9 @@
 #define OMAPFB_MEMTYPE_SRAM		1
 #define OMAPFB_MEMTYPE_MAX		1
 
+#define OMAPFB_MEM_IDX_ENABLED	0x80
+#define OMAPFB_MEM_IDX_MASK	0x7f
+
 enum omapfb_color_format {
 	OMAPFB_COLOR_RGB565 = 0,
 	OMAPFB_COLOR_YUV422,
@@ -136,7 +139,7 @@
 	__u8  enabled;
 	__u8  channel_out;
 	__u8  mirror;
-	__u8  reserved1;
+	__u8  mem_idx;
 	__u32 out_width;
 	__u32 out_height;
 	__u32 reserved2[12];