From mboxrd@z Thu Jan 1 00:00:00 1970 From: Laurent Pinchart Subject: Re: [PATCH 06/19] drm/blend: Add a generic alpha property Date: Tue, 09 Jan 2018 14:34:47 +0200 Message-ID: <2691997.qmgyvrLtFu@avalon> References: <5c765fc730d75cb362dc37bcdb3b3aeacc7bdb30.1515494838.git-series.maxime.ripard@free-electrons.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <5c765fc730d75cb362dc37bcdb3b3aeacc7bdb30.1515494838.git-series.maxime.ripard@free-electrons.com> Sender: linux-kernel-owner@vger.kernel.org To: dri-devel@lists.freedesktop.org Cc: Maxime Ripard , Chen-Yu Tsai , Daniel Vetter , Jani Nikula , Sean Paul , Thomas Petazzoni , Boris Brezillon , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, thomas@vitsch.nl List-Id: dri-devel@lists.freedesktop.org Hi Maxime, Thank you for the patch. On Tuesday, 9 January 2018 12:56:25 EET Maxime Ripard wrote: > Some drivers duplicate the logic to create a property to store a per-plane > alpha. >=20 > Let's create a helper in order to move that to the core. >=20 > Cc: Boris Brezillon > Cc: Laurent Pinchart > Signed-off-by: Maxime Ripard > --- > Documentation/gpu/kms-properties.csv | 2 +- > drivers/gpu/drm/drm_atomic.c | 4 ++++- > drivers/gpu/drm/drm_atomic_helper.c | 1 +- > drivers/gpu/drm/drm_blend.c | 32 +++++++++++++++++++++++++++++- > include/drm/drm_blend.h | 1 +- > include/drm/drm_plane.h | 6 +++++- > 6 files changed, 45 insertions(+), 1 deletion(-) >=20 > diff --git a/Documentation/gpu/kms-properties.csv > b/Documentation/gpu/kms-properties.csv index 927b65e14219..a3c3969c1992 > 100644 > --- a/Documentation/gpu/kms-properties.csv > +++ b/Documentation/gpu/kms-properties.csv > @@ -99,5 +99,5 @@ radeon,DVI-I,=E2=80=9Ccoherent=E2=80=9D,RANGE,"Min=3D0,= Max=3D1",Connector,TBD > ,,"""underscan vborder""",RANGE,"Min=3D0, Max=3D128",Connector,TBD > ,Audio,=E2=80=9Caudio=E2=80=9D,ENUM,"{ ""off"", ""on"", ""auto"" }",Conn= ector,TBD > ,FMT Dithering,=E2=80=9Cdither=E2=80=9D,ENUM,"{ ""off"", ""on"" }",Conne= ctor,TBD > -rcar-du,Generic,"""alpha""",RANGE,"Min=3D0, Max=3D255",Plane,TBD > +,,"""alpha""",RANGE,"Min=3D0, Max=3D255",Plane,Opacity of the plane from > transparent (0) to opaque (255) ,,"""colorkey""",RANGE,"Min=3D0, > Max=3D0x01ffffff",Plane,TBD I think more documentation is needed. You should explain how the property=20 operates and which formats it is applicable to. For instance you need to=20 clarify what happens for format that contain an alpha component. > diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c > index c2da5585e201..ade18cf62c89 100644 > --- a/drivers/gpu/drm/drm_atomic.c > +++ b/drivers/gpu/drm/drm_atomic.c > @@ -749,6 +749,8 @@ static int drm_atomic_plane_set_property(struct > drm_plane *plane, state->src_w =3D val; > } else if (property =3D=3D config->prop_src_h) { > state->src_h =3D val; > + } else if (property =3D=3D plane->alpha_property) { > + state->alpha =3D val; > } else if (property =3D=3D plane->rotation_property) { > if (!is_power_of_2(val & DRM_MODE_ROTATE_MASK)) > return -EINVAL; > @@ -810,6 +812,8 @@ drm_atomic_plane_get_property(struct drm_plane *plane, > *val =3D state->src_w; > } else if (property =3D=3D config->prop_src_h) { > *val =3D state->src_h; > + } else if (property =3D=3D plane->alpha_property) { > + *val =3D state->alpha; > } else if (property =3D=3D plane->rotation_property) { > *val =3D state->rotation; > } else if (property =3D=3D plane->zpos_property) { > diff --git a/drivers/gpu/drm/drm_atomic_helper.c > b/drivers/gpu/drm/drm_atomic_helper.c index 71d712f1b56a..018993df4c18 > 100644 > --- a/drivers/gpu/drm/drm_atomic_helper.c > +++ b/drivers/gpu/drm/drm_atomic_helper.c > @@ -3372,6 +3372,7 @@ void drm_atomic_helper_plane_reset(struct drm_plane > *plane) >=20 > if (plane->state) { > plane->state->plane =3D plane; > + plane->state->alpha =3D 255; If you keep the ability to select an initial value other than fully opaque= =20 (see my comment below about that) you should reset to that value instead of= =20 hardcoding 255. > plane->state->rotation =3D DRM_MODE_ROTATE_0; > } > } > diff --git a/drivers/gpu/drm/drm_blend.c b/drivers/gpu/drm/drm_blend.c > index 2e5e089dd912..8eea2a8af458 100644 > --- a/drivers/gpu/drm/drm_blend.c > +++ b/drivers/gpu/drm/drm_blend.c > @@ -104,6 +104,38 @@ > */ >=20 > /** > + * drm_plane_create_alpha_property - create a new alpha property > + * @plane: drm plane > + * @alpha: initial value of alpha, from 0 (transparent) to 255 (opaque) Do you have a use case for initializing the alpha value to something else t= han=20 fully opaque ? > + * This function initializes a generic, mutable, alpha property and > + * enables support for it in the DRM core. > + * > + * Drivers can then attach this property to their plane to enable > + * support for configurable plane alpha. The function attaches the property to the plane, is the documentation outda= ted=20 ? > + * Returns: > + * 0 on success, negative error code on failure. > + */ > +int drm_plane_create_alpha_property(struct drm_plane *plane, u8 alpha) > +{ > + struct drm_property *prop; > + > + prop =3D drm_property_create_range(plane->dev, 0, "alpha", 0, 255); Do you think the 0-255 range will fit all use cases ? > + if (!prop) > + return -ENOMEM; > + > + drm_object_attach_property(&plane->base, prop, alpha); > + plane->alpha_property =3D prop; > + > + if (plane->state) > + plane->state->alpha =3D alpha; > + > + 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..5979a8fce453 100644 > --- a/include/drm/drm_blend.h > +++ b/include/drm/drm_blend.h > @@ -36,6 +36,7 @@ static inline bool drm_rotation_90_or_270(unsigned int > rotation) return rotation & (DRM_MODE_ROTATE_90 | DRM_MODE_ROTATE_270); > } >=20 > +int drm_plane_create_alpha_property(struct drm_plane *plane, u8 alpha); > 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 571615079230..a5e26064b132 100644 > --- a/include/drm/drm_plane.h > +++ b/include/drm/drm_plane.h > @@ -42,6 +42,7 @@ 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 identic= al > @@ -105,6 +106,9 @@ struct drm_plane_state { > uint32_t src_x, src_y; > uint32_t src_h, src_w; >=20 > + /* Plane opacity */ > + u8 alpha; > + > /* Plane rotation */ > unsigned int rotation; >=20 > @@ -481,6 +485,7 @@ 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 > @@ -546,6 +551,7 @@ struct drm_plane { > */ > struct drm_plane_state *state; >=20 > + struct drm_property *alpha_property; > struct drm_property *zpos_property; > struct drm_property *rotation_property; > }; =2D-=20 Regards, Laurent Pinchart