diff options
| -rw-r--r-- | Documentation/gpu/drm-kms.rst | 6 | ||||
| -rw-r--r-- | drivers/gpu/drm/drm_crtc.c | 27 |
2 files changed, 33 insertions, 0 deletions
diff --git a/Documentation/gpu/drm-kms.rst b/Documentation/gpu/drm-kms.rst index 397314d08f77..975cfeb8a353 100644 --- a/Documentation/gpu/drm-kms.rst +++ b/Documentation/gpu/drm-kms.rst @@ -460,6 +460,12 @@ HDMI Specific Connector Properties .. kernel-doc:: drivers/gpu/drm/drm_connector.c :doc: HDMI connector properties +Standard CRTC Properties +------------------------ + +.. kernel-doc:: drivers/gpu/drm/drm_crtc.c + :doc: standard CRTC properties + Plane Composition Properties ---------------------------- diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c index 4936e1080e41..f1216088f65f 100644 --- a/drivers/gpu/drm/drm_crtc.c +++ b/drivers/gpu/drm/drm_crtc.c @@ -205,6 +205,33 @@ struct dma_fence *drm_crtc_create_fence(struct drm_crtc *crtc) } /** + * DOC: standard CRTC properties + * + * DRM CRTCs have a few standardized properties: + * + * ACTIVE: + * Atomic property for setting the power state of the CRTC. When set to 1 + * the CRTC will actively display content. When set to 0 the CRTC will be + * powered off. There is no expectation that user-space will reset CRTC + * resources like the mode and planes when setting ACTIVE to 0. + * + * User-space can rely on an ACTIVE change to 1 to never fail an atomic + * test as long as no other property has changed. If a change to ACTIVE + * fails an atomic test, this is a driver bug. For this reason setting + * ACTIVE to 0 must not release internal resources (like reserved memory + * bandwidth or clock generators). + * + * Note that the legacy DPMS property on connectors is internally routed + * to control this property for atomic drivers. + * MODE_ID: + * Atomic property for setting the CRTC display timings. The value is the + * ID of a blob containing the DRM mode info. To disable the CRTC, + * user-space must set this property to 0. + * + * Setting MODE_ID to 0 will release reserved resources for the CRTC. + */ + +/** * drm_crtc_init_with_planes - Initialise a new CRTC object with * specified primary and cursor planes. * @dev: DRM device |