Some drivers duplicate the logic to create a property to store a per-plane alpha.
This is especially useful if we ever want to support extra protocols for Wayland like: https://lists.freedesktop.org/archives/wayland-devel/2017-August/034741.html
Let's create a helper in order to move that to the core.
Reviewed-by: Boris Brezillon boris.brezillon@bootlin.com Reviewed-by: Eric Anholt eric@anholt.net Reviewed-by: Laurent Pinchart laurent.pinchart@ideasonboard.com Reviewed-by: Paul Kocialkowski paul.kocialkowski@bootlin.com Signed-off-by: Maxime Ripard maxime.ripard@bootlin.com --- drivers/gpu/drm/drm_atomic.c | 4 +++- drivers/gpu/drm/drm_atomic_helper.c | 4 +++- drivers/gpu/drm/drm_blend.c | 39 ++++++++++++++++++++++++++++++- include/drm/drm_blend.h | 3 ++- include/drm/drm_plane.h | 6 +++++- 5 files changed, 56 insertions(+)
diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c index 7d25c42f22db..3d9ae057a6cd 100644 --- a/drivers/gpu/drm/drm_atomic.c +++ b/drivers/gpu/drm/drm_atomic.c @@ -783,6 +783,8 @@ static int drm_atomic_plane_set_property(struct drm_plane *plane, state->src_w = val; } else if (property == config->prop_src_h) { state->src_h = val; + } else if (property == plane->alpha_property) { + state->alpha = val; } else if (property == plane->rotation_property) { if (!is_power_of_2(val & DRM_MODE_ROTATE_MASK)) return -EINVAL; @@ -848,6 +850,8 @@ drm_atomic_plane_get_property(struct drm_plane *plane, *val = state->src_w; } else if (property == config->prop_src_h) { *val = state->src_h; + } else if (property == plane->alpha_property) { + *val = state->alpha; } else if (property == plane->rotation_property) { *val = state->rotation; } else if (property == plane->zpos_property) { diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c index ee03c1ed2521..0587a0a2f3aa 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -3500,6 +3500,10 @@ void drm_atomic_helper_plane_reset(struct drm_plane *plane) if (plane->state) { plane->state->plane = plane; plane->state->rotation = DRM_MODE_ROTATE_0; + + /* Reset the alpha value to fully opaque if it matters */ + if (plane->alpha_property) + plane->state->alpha = plane->alpha_property->values[1]; } } EXPORT_SYMBOL(drm_atomic_helper_plane_reset); 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 diff --git a/include/drm/drm_blend.h b/include/drm/drm_blend.h index 17606026590b..330c561c4c11 100644 --- a/include/drm/drm_blend.h +++ b/include/drm/drm_blend.h @@ -36,6 +36,9 @@ static inline bool drm_rotation_90_or_270(unsigned int rotation) return rotation & (DRM_MODE_ROTATE_90 | DRM_MODE_ROTATE_270); }
+#define DRM_BLEND_ALPHA_OPAQUE 0xffff + +int drm_plane_create_alpha_property(struct drm_plane *plane); int drm_plane_create_rotation_property(struct drm_plane *plane, unsigned int rotation, unsigned int supported_rotations); diff --git a/include/drm/drm_plane.h b/include/drm/drm_plane.h index d6da26d66a4b..9563bd25f19b 100644 --- a/include/drm/drm_plane.h +++ b/include/drm/drm_plane.h @@ -43,6 +43,7 @@ struct drm_modeset_acquire_ctx; * plane (in 16.16) * @src_w: width of visible portion of plane (in 16.16) * @src_h: height of visible portion of plane (in 16.16) + * @alpha: opacity of the plane * @rotation: rotation of the plane * @zpos: priority of the given plane on crtc (optional) * Note that multiple active planes on the same crtc can have an identical @@ -106,6 +107,9 @@ struct drm_plane_state { uint32_t src_x, src_y; uint32_t src_h, src_w;
+ /* Plane opacity */ + u16 alpha; + /* Plane rotation */ unsigned int rotation;
@@ -496,6 +500,7 @@ enum drm_plane_type { * @funcs: helper functions * @properties: property tracking for this plane * @type: type of plane (overlay, primary, cursor) + * @alpha_property: alpha property for this plane * @zpos_property: zpos property for this plane * @rotation_property: rotation property for this plane * @helper_private: mid-layer private data @@ -571,6 +576,7 @@ struct drm_plane { */ struct drm_plane_state *state;
+ struct drm_property *alpha_property; struct drm_property *zpos_property; struct drm_property *rotation_property;