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Diffstat (limited to 'drivers/gpu/drm/drm_plane.c')
| -rw-r--r-- | drivers/gpu/drm/drm_plane.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_plane.c b/drivers/gpu/drm/drm_plane.c index 4a66374dc355..b15b65e48555 100644 --- a/drivers/gpu/drm/drm_plane.c +++ b/drivers/gpu/drm/drm_plane.c @@ -54,6 +54,12 @@ * enum drm_plane_type). A plane can be compatible with multiple CRTCs, see * &drm_plane.possible_crtcs. * + * Each CRTC must have a unique primary plane userspace can attach to enable + * the CRTC. In other words, userspace must be able to attach a different + * primary plane to each CRTC at the same time. Primary planes can still be + * compatible with multiple CRTCs. There must be exactly as many primary planes + * as there are CRTCs. + * * Legacy uAPI doesn't expose the primary and cursor planes directly. DRM core * relies on the driver to set the primary and optionally the cursor plane used * for legacy IOCTLs. This is done by calling drm_crtc_init_with_planes(). All |