drm: Add drm_crtc_init_with_planes() (v2)

Add a new drm_crtc_init_with_planes() to allow drivers to provide
specific primary and cursor planes at CRTC initialization.  The existing
drm_crtc_init() interface remains to avoid driver churn in existing
drivers; it will initialize the CRTC with a plane helper-created primary
plane and no cursor plane.

v2:
  - Move drm_crtc_init() to plane helper file so that nothing in the DRM
    core depends on helpers.  [suggested by Daniel Vetter]
  - Keep cursor parameter to drm_crtc_init_with_planes() a void* until
    we actually add cursor support.  [suggested by Daniel Vetter]

Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>

1 files changed, 21 insertions, 0 deletions

diff --git a/drivers/gpu/drm/drm_plane_helper.c b/drivers/gpu/drm/drm_plane_helper.c
index 2f2374aba42e..e768d35ff22e 100644
--- a/drivers/gpu/drm/drm_plane_helper.c
+++ b/drivers/gpu/drm/drm_plane_helper.c
@@ -310,3 +310,24 @@ struct drm_plane *drm_primary_helper_create_plane(struct drm_device *dev,
 }
 EXPORT_SYMBOL(drm_primary_helper_create_plane);
 
+/**
+ * drm_crtc_init - Legacy CRTC initialization function
+ * @dev: DRM device
+ * @crtc: CRTC object to init
+ * @funcs: callbacks for the new CRTC
+ *
+ * Initialize a CRTC object with a default helper-provided primary plane and no
+ * cursor plane.
+ *
+ * Returns:
+ * Zero on success, error code on failure.
+ */
+int drm_crtc_init(struct drm_device *dev, struct drm_crtc *crtc,
+		  const struct drm_crtc_funcs *funcs)
+{
+	struct drm_plane *primary;
+
+	primary = drm_primary_helper_create_plane(dev, NULL, 0);
+	return drm_crtc_init_with_planes(dev, crtc, primary, NULL, funcs);
+}
+EXPORT_SYMBOL(drm_crtc_init);