diff options
Diffstat (limited to 'drivers/gpu/drm/drm_blend.c')
| -rw-r--r-- | drivers/gpu/drm/drm_blend.c | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_blend.c b/drivers/gpu/drm/drm_blend.c index 5a81e1b4c076..a16a74d7e15e 100644 --- a/drivers/gpu/drm/drm_blend.c +++ b/drivers/gpu/drm/drm_blend.c @@ -88,6 +88,13 @@ * On top of this basic transformation additional properties can be exposed by * the driver: * + * alpha: + * Alpha is setup with drm_plane_create_alpha_property(). It controls the + * plane-wide opacity, from transparent (0) to opaque (0xffff). It can be + * combined with pixel alpha. + * The pixel values in the framebuffers are expected to not be + * pre-multiplied by the global alpha associated to the plane. + * * rotation: * Rotation is set up with drm_plane_create_rotation_property(). It adds a * rotation and reflection step between the source and destination rectangles. @@ -106,6 +113,38 @@ */ /** + * drm_plane_create_alpha_property - create a new alpha property + * @plane: drm plane + * + * This function creates a generic, mutable, alpha property and enables support + * for it in the DRM core. It is attached to @plane. + * + * The alpha property will be allowed to be within the bounds of 0 + * (transparent) to 0xffff (opaque). + * + * Returns: + * 0 on success, negative error code on failure. + */ +int drm_plane_create_alpha_property(struct drm_plane *plane) +{ + struct drm_property *prop; + + prop = drm_property_create_range(plane->dev, 0, "alpha", + 0, DRM_BLEND_ALPHA_OPAQUE); + if (!prop) + return -ENOMEM; + + drm_object_attach_property(&plane->base, prop, DRM_BLEND_ALPHA_OPAQUE); + plane->alpha_property = prop; + + if (plane->state) + plane->state->alpha = DRM_BLEND_ALPHA_OPAQUE; + + return 0; +} +EXPORT_SYMBOL(drm_plane_create_alpha_property); + +/** * drm_plane_create_rotation_property - create a new rotation property * @plane: drm plane * @rotation: initial value of the rotation property |