101  * rotation:
102  *	Rotation is set up with drm_plane_create_rotation_property(). It adds a
103  *	rotation and reflection step between the source and destination rectangles.
232  * drm_plane_create_rotation_property - create a new rotation property
234  * @rotation: initial value of the rotation property
239  * Since a rotation by 180° degress is the same as reflecting both along the x
240  * and the y axis the rotation property is somewhat redundant. Drivers can use
244  * drm_property_create_bitmask()) called "rotation" and has the following
260  * Rotation is the specified amount in degrees in counter clockwise direction,
262  * rotation. After reflection, the rotation is applied to the image sampled from
266 				       unsigned int rotation,  in drm_plane_create_rotation_property()  argument
280 	WARN_ON(!is_power_of_2(rotation & DRM_MODE_ROTATE_MASK));  in drm_plane_create_rotation_property()
281 	WARN_ON(rotation & ~supported_rotations);  in drm_plane_create_rotation_property()
283 	prop = drm_property_create_bitmask(plane->dev, 0, "rotation",  in drm_plane_create_rotation_property()
289 	drm_object_attach_property(&plane->base, prop, rotation);  in drm_plane_create_rotation_property()
292 		plane->state->rotation = rotation;  in drm_plane_create_rotation_property()
301  * drm_rotation_simplify() - Try to simplify the rotation
302  * @rotation: Rotation to be simplified
305  * Attempt to simplify the rotation to a form that is supported.
309  * drm_rotation_simplify(rotation, DRM_MODE_ROTATE_0 |
318 unsigned int drm_rotation_simplify(unsigned int rotation,  in drm_rotation_simplify()  argument
321 	if (rotation & ~supported_rotations) {  in drm_rotation_simplify()
322 		rotation ^= DRM_MODE_REFLECT_X | DRM_MODE_REFLECT_Y;  in drm_rotation_simplify()
323 		rotation = (rotation & DRM_MODE_REFLECT_MASK) |  in drm_rotation_simplify()
324 		           BIT((ffs(rotation & DRM_MODE_ROTATE_MASK) + 1)  in drm_rotation_simplify()
328 	return rotation;  in drm_rotation_simplify()