drm: Describe the Rotation property bits.

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@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Robert Fekete 2015-11-02 16:14:08 +01:00 committed by Daniel Vetter
parent cb1197173f
commit d9c3824217

View file

@ -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