| Message ID | 20201217113220.102271-5-contact@emersion.fr (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/doc: misc documentation improvements | expand |
On Thu, Dec 17, 2020 at 12:32:15PM +0100, Simon Ser wrote: > The docs for enum drm_plane_type mention legacy IOCTLs, however the > plane type is not tied to legacy IOCTLs, the drm_cursor.primary and > cursor fields are. Add a small paragraph to reference these. > > Instead, document expectations for primary and cursor planes for > non-legacy userspace. Note that these docs are for driver developers, > not userspace developers, so internal kernel APIs are mentionned. > > Signed-off-by: Simon Ser <contact@emersion.fr> > Cc: Daniel Vetter <daniel@ffwll.ch> > Cc: Pekka Paalanen <ppaalanen@gmail.com> > --- > include/drm/drm_plane.h | 29 +++++++++++++++++++++-------- > 1 file changed, 21 insertions(+), 8 deletions(-) > > diff --git a/include/drm/drm_plane.h b/include/drm/drm_plane.h > index 1d82b264e5e4..5b180d07788e 100644 > --- a/include/drm/drm_plane.h > +++ b/include/drm/drm_plane.h > @@ -538,10 +538,14 @@ struct drm_plane_funcs { > * > * For compatibility with legacy userspace, only overlay planes are made > * available to userspace by default. Userspace clients may set the > - * DRM_CLIENT_CAP_UNIVERSAL_PLANES client capability bit to indicate that they > + * &DRM_CLIENT_CAP_UNIVERSAL_PLANES client capability bit to indicate that they > * wish to receive a universal plane list containing all plane types. See also > * drm_for_each_legacy_plane(). > * > + * In addition to setting each plane's type, drivers need to setup the > + * &drm_crtc.primary and optionally &drm_crtc.cursor pointers for legacy > + * IOCTLs. See drm_crtc_init_with_planes(). > + * > * WARNING: The values of this enum is UABI since they're exposed in the "type" > * property. > */ > @@ -557,19 +561,28 @@ enum drm_plane_type { > /** > * @DRM_PLANE_TYPE_PRIMARY: > * > - * Primary planes represent a "main" plane for a CRTC. Primary planes > - * are the planes operated upon by CRTC modesetting and flipping > - * operations described in the &drm_crtc_funcs.page_flip and > - * &drm_crtc_funcs.set_config hooks. > + * A primary plane attached to a CRTC is the most likely to be able to > + * light up the CRTC when no scaling/cropping is used and the plane > + * covers the whole CRTC. > + * > + * In addition to setting a plane type to primary, drivers need to > + * setup the &drm_crtc.primary pointer for legacy IOCTLs. See > + * drm_crtc_init_with_planes(). After you brought it up I'm actually fine with not duplicating this. Either way: Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> > */ > DRM_PLANE_TYPE_PRIMARY, > > /** > * @DRM_PLANE_TYPE_CURSOR: > * > - * Cursor planes represent a "cursor" plane for a CRTC. Cursor planes > - * are the planes operated upon by the DRM_IOCTL_MODE_CURSOR and > - * DRM_IOCTL_MODE_CURSOR2 IOCTLs. > + * A cursor plane attached to a CRTC is more likely to be able to be > + * enabled when no scaling/cropping is used and the framebuffer has the > + * size indicated by &drm_mode_config.cursor_width and > + * &drm_mode_config.cursor_height. Additionally, if the driver doesn't > + * support modifiers, the framebuffer should have a linear layout. > + * > + * In addition to setting a plane type to cursor, drivers need to setup > + * the &drm_crtc.cursor pointer for legacy IOCTLs. See > + * drm_crtc_init_with_planes(). > */ > DRM_PLANE_TYPE_CURSOR, > }; > -- > 2.29.2 >
diff --git a/include/drm/drm_plane.h b/include/drm/drm_plane.h index 1d82b264e5e4..5b180d07788e 100644 --- a/include/drm/drm_plane.h +++ b/include/drm/drm_plane.h @@ -538,10 +538,14 @@ struct drm_plane_funcs { * * For compatibility with legacy userspace, only overlay planes are made * available to userspace by default. Userspace clients may set the - * DRM_CLIENT_CAP_UNIVERSAL_PLANES client capability bit to indicate that they + * &DRM_CLIENT_CAP_UNIVERSAL_PLANES client capability bit to indicate that they * wish to receive a universal plane list containing all plane types. See also * drm_for_each_legacy_plane(). * + * In addition to setting each plane's type, drivers need to setup the + * &drm_crtc.primary and optionally &drm_crtc.cursor pointers for legacy + * IOCTLs. See drm_crtc_init_with_planes(). + * * WARNING: The values of this enum is UABI since they're exposed in the "type" * property. */ @@ -557,19 +561,28 @@ enum drm_plane_type { /** * @DRM_PLANE_TYPE_PRIMARY: * - * Primary planes represent a "main" plane for a CRTC. Primary planes - * are the planes operated upon by CRTC modesetting and flipping - * operations described in the &drm_crtc_funcs.page_flip and - * &drm_crtc_funcs.set_config hooks. + * A primary plane attached to a CRTC is the most likely to be able to + * light up the CRTC when no scaling/cropping is used and the plane + * covers the whole CRTC. + * + * In addition to setting a plane type to primary, drivers need to + * setup the &drm_crtc.primary pointer for legacy IOCTLs. See + * drm_crtc_init_with_planes(). */ DRM_PLANE_TYPE_PRIMARY, /** * @DRM_PLANE_TYPE_CURSOR: * - * Cursor planes represent a "cursor" plane for a CRTC. Cursor planes - * are the planes operated upon by the DRM_IOCTL_MODE_CURSOR and - * DRM_IOCTL_MODE_CURSOR2 IOCTLs. + * A cursor plane attached to a CRTC is more likely to be able to be + * enabled when no scaling/cropping is used and the framebuffer has the + * size indicated by &drm_mode_config.cursor_width and + * &drm_mode_config.cursor_height. Additionally, if the driver doesn't + * support modifiers, the framebuffer should have a linear layout. + * + * In addition to setting a plane type to cursor, drivers need to setup + * the &drm_crtc.cursor pointer for legacy IOCTLs. See + * drm_crtc_init_with_planes(). */ DRM_PLANE_TYPE_CURSOR, };
The docs for enum drm_plane_type mention legacy IOCTLs, however the plane type is not tied to legacy IOCTLs, the drm_cursor.primary and cursor fields are. Add a small paragraph to reference these. Instead, document expectations for primary and cursor planes for non-legacy userspace. Note that these docs are for driver developers, not userspace developers, so internal kernel APIs are mentionned. Signed-off-by: Simon Ser <contact@emersion.fr> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Pekka Paalanen <ppaalanen@gmail.com> --- include/drm/drm_plane.h | 29 +++++++++++++++++++++-------- 1 file changed, 21 insertions(+), 8 deletions(-)