drm: clarify scaling property names

Now that we're using the scaling property in the Intel driver I noticed
that the names were a bit confusing.  I've corrected them according to
our discussion on IRC and the mailing list, though I've left out
potential new additions for a new scaling property with an integer (or
two) for the scaling factor.  None of the drivers implement that today,
but if someone wants to do it, I think it could be done with the
addition of a single new type and a new property to describe the
scaling factor in the X and Y directions.

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Acked-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/include/drm/drm_mode.h b/include/drm/drm_mode.h
index 616aeb4..1f90841 100644
--- a/include/drm/drm_mode.h
+++ b/include/drm/drm_mode.h
@@ -68,10 +68,11 @@
 #define DRM_MODE_DPMS_OFF	3
 
 /* Scaling mode options */
-#define DRM_MODE_SCALE_NON_GPU		0
-#define DRM_MODE_SCALE_FULLSCREEN	1
-#define DRM_MODE_SCALE_NO_SCALE		2
-#define DRM_MODE_SCALE_ASPECT		3
+#define DRM_MODE_SCALE_NONE		0 /* Unmodified timing (display or
+					     software can still scale) */
+#define DRM_MODE_SCALE_FULLSCREEN	1 /* Full screen, ignore aspect */
+#define DRM_MODE_SCALE_CENTER		2 /* Centered, no scaling */
+#define DRM_MODE_SCALE_ASPECT		3 /* Full screen, preserve aspect */
 
 /* Dithering mode options */
 #define DRM_MODE_DITHERING_OFF	0