[PATCH 1/9] drm: Introduce the blend-func property

Vandita Kulkarni
2016-01-18T07:32:14Z

From: Damien Lespiau <damien.lespiau@intel.com>

We'd like to be able to program the blending modes of display planes.
Ville suggested to use something similar to the GL blend states, which
does seem like a good idea.

For now, we only consider blend factors, but room is left for
extensions: blend equation, separate rgb/alpha blend factors, blend
color.

V2: Added the belnd func property support in get property.

Suggested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Vandita Kulkarni <vandita.kulkarni@intel.com>
---
Documentation/DocBook/gpu.tmpl | 11 +++++++++--
drivers/gpu/drm/drm_atomic.c | 14 ++++++++++++++
drivers/gpu/drm/drm_crtc.c | 5 +++++
include/drm/drm_crtc.h | 20 ++++++++++++++++++++
4 files changed, 48 insertions(+), 2 deletions(-)

diff --git a/Documentation/DocBook/gpu.tmpl b/Documentation/DocBook/gpu.tmpl
index 351e801..2017162 100644
--- a/Documentation/DocBook/gpu.tmpl
+++ b/Documentation/DocBook/gpu.tmpl
@@ -1816,7 +1816,7 @@ void intel_crt_init(struct drm_device *dev)
Description/Restrictions


- DRM
+ DRM
Generic
“rotation”
BITMASK
@@ -1868,7 +1868,7 @@ void intel_crt_init(struct drm_device *dev)
CRTC that connector is attached to (atomic)


- Plane
+ Plane
“type”
ENUM | IMMUTABLE
{ "Overlay", "Primary", "Cursor" }
@@ -1946,6 +1946,13 @@ void intel_crt_init(struct drm_device *dev)
CRTC that plane is attached to (atomic)


+ “blend_func”
+ None
+ DRM_BLEND_FUNC()
+ Plane
+ Source and destination blending factors
+
+
DVI-I
“subconnector”
ENUM
diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index 3f74193..0c165c6 100644
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -630,6 +630,18 @@ int drm_atomic_plane_set_property(struct drm_plane *plane,
state->src_h = val;
} else if (property == config->rotation_property) {
state->rotation = val;
+ } else if (property == config->prop_blend_func) {
+ enum drm_blend_factor src_factor, dst_factor;
+
+ src_factor = DRM_BLEND_FUNC_SRC_FACTOR(val);
+ dst_factor = DRM_BLEND_FUNC_DST_FACTOR(val);
+
+ if (src_factor != dst_factor &&
+ (src_factor == DRM_BLEND_FACTOR_AUTO ||
+ dst_factor == DRM_BLEND_FACTOR_AUTO))
+ return -EINVAL;
+
+ state->blend_mode.func = val & GENMASK(31, 0);
} else if (plane->funcs->atomic_set_property) {
return plane->funcs->atomic_set_property(plane, state,
property, val);
@@ -686,6 +698,8 @@ drm_atomic_plane_get_property(struct drm_plane *plane,
*val = state->src_h;
} else if (property == config->rotation_property) {
*val = state->rotation;
+ } else if (property == config->prop_blend_func) {
+ *val = state->blend_mode.func;
} else if (plane->funcs->atomic_get_property) {
return plane->funcs->atomic_get_property(plane, state, property, val);
} else {
diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index 62fa95f..b8dde06 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -1542,6 +1542,11 @@ static int drm_mode_create_standard_properties(struct drm_device *dev)
return -ENOMEM;
dev->mode_config.prop_mode_id = prop;

+ prop = drm_property_create_range(dev, 0, "blend_func", 0, U32_MAX);
+ if (!prop)
+ return -ENOMEM;
+ dev->mode_config.prop_blend_func = prop;
+
return 0;
}

diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index c65a212..9cfe601 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -99,6 +99,23 @@ static inline uint64_t I642U64(int64_t val)
#define DRM_REFLECT_X 4
#define DRM_REFLECT_Y 5

+enum drm_blend_factor {
+ DRM_BLEND_FACTOR_AUTO,
+ DRM_BLEND_FACTOR_ZERO,
+ DRM_BLEND_FACTOR_ONE,
+ DRM_BLEND_FACTOR_SRC_ALPHA,
+ DRM_BLEND_FACTOR_ONE_MINUS_SRC_ALPHA,
+};
+
+#define DRM_BLEND_FUNC(src_factor, dst_factor) \
+ (DRM_BLEND_FACTOR_##src_factor << 16 | DRM_BLEND_FACTOR_##dst_factor)
+#define DRM_BLEND_FUNC_SRC_FACTOR(val) (((val) >> 16) & 0xffff)
+#define DRM_BLEND_FUNC_DST_FACTOR(val) ((val) & 0xffff)
+
+struct drm_blend_mode {
+ uint64_t func;
+};
+
enum drm_connector_force {
DRM_FORCE_UNSPECIFIED,
DRM_FORCE_OFF,
@@ -1267,6 +1284,8 @@ struct drm_plane_state {
/* Plane rotation */
unsigned int rotation;

+ struct drm_blend_mode blend_mode;
+
struct drm_atomic_state *state;
};

@@ -2099,6 +2118,7 @@ struct drm_mode_config {
struct drm_property *prop_crtc_id;
struct drm_property *prop_active;
struct drm_property *prop_mode_id;
+ struct drm_property *prop_blend_func;

/* DVI-I properties */
struct drm_property *dvi_i_subconnector_property;