[Intel-gfx] [PATCH v2] drm: Describe the Rotation property bits.

[Robert Fekete]

    Adds clarification of the rotation property bits. I.e. rotation is
    counter clockwise and that reflects are applied before any rotation.

    v2: Refer to the define names instead of the property values.

Signed-off-by: Robert Fekete <robert.fekete at linux.intel.com>
---
 include/drm/drm_crtc.h | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 3f0c6909dda1..f47cefa37ef3 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -85,7 +85,11 @@ static inline uint64_t I642U64(int64_t val)
 	return (uint64_t)*((uint64_t *)&val);
 }
 
-/* rotation property bits */
+/*
+ * Rotation property bits. DRM_ROTATE_<degrees> rotates the image by the
+ * specified amount in degrees in counter clockwise direction. DRM_REFLECT_X and
+ * DRM_REFLECT_Y reflects the image along the specified axis prior to rotation
+ */
 #define DRM_ROTATE_MASK 0x0f
 #define DRM_ROTATE_0	0
 #define DRM_ROTATE_90	1
-- 
1.9.1