drm/atomic: Add connector atomic_check function, v2.
The atomic_check function is useful for implementing properties, but
it can be used for other connector modeset related checks as well.
Similar to plane check functions, on a modeset atomic_check() is always
called.
Changes since v1:
- Make sure atomic_check() is called on any modeset.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: http://patchwork.freedesktop.org/patch/msgid/1491477543-31257-5-git-send-email-maarten.lankhorst@linux.intel.com
diff --git a/include/drm/drm_modeset_helper_vtables.h b/include/drm/drm_modeset_helper_vtables.h
index 7847bab..c01c328 100644
--- a/include/drm/drm_modeset_helper_vtables.h
+++ b/include/drm/drm_modeset_helper_vtables.h
@@ -872,6 +872,40 @@ struct drm_connector_helper_funcs {
*/
struct drm_encoder *(*atomic_best_encoder)(struct drm_connector *connector,
struct drm_connector_state *connector_state);
+
+ /**
+ * @atomic_check:
+ *
+ * This hook is used to validate connector state. This function is
+ * called from &drm_atomic_helper_check_modeset, and is called when
+ * a connector property is set, or a modeset on the crtc is forced.
+ *
+ * Because &drm_atomic_helper_check_modeset may be called multiple times,
+ * this function should handle being called multiple times as well.
+ *
+ * This function is also allowed to inspect any other object's state and
+ * can add more state objects to the atomic commit if needed. Care must
+ * be taken though to ensure that state check and compute functions for
+ * these added states are all called, and derived state in other objects
+ * all updated. Again the recommendation is to just call check helpers
+ * until a maximal configuration is reached.
+ *
+ * NOTE:
+ *
+ * This function is called in the check phase of an atomic update. The
+ * driver is not allowed to change anything outside of the free-standing
+ * state objects passed-in or assembled in the overall &drm_atomic_state
+ * update tracking structure.
+ *
+ * RETURNS:
+ *
+ * 0 on success, -EINVAL if the state or the transition can't be
+ * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
+ * attempt to obtain another state object ran into a &drm_modeset_lock
+ * deadlock.
+ */
+ int (*atomic_check)(struct drm_connector *connector,
+ struct drm_connector_state *state);
};
/**
