Current code is quite a mess unfortunately, so also add a todo.rst entry to maybe fix it up eventually.
Cc: Michel Dänzer michel@daenzer.net Signed-off-by: Daniel Vetter daniel.vetter@intel.com --- Documentation/gpu/todo.rst | 12 ++++++++++++ drivers/gpu/drm/drm_connector.c | 10 ++++++++-- drivers/gpu/drm/drm_dp_helper.c | 8 ++++++++ 3 files changed, 28 insertions(+), 2 deletions(-)
diff --git a/Documentation/gpu/todo.rst b/Documentation/gpu/todo.rst index 32787acff0a8..8dc147c93c9c 100644 --- a/Documentation/gpu/todo.rst +++ b/Documentation/gpu/todo.rst @@ -284,6 +284,18 @@ drm_fb_helper tasks removed: drm_fb_helper_single_add_all_connectors(), drm_fb_helper_add_one_connector() and drm_fb_helper_remove_one_connector().
+connector register/unregister fixes +----------------------------------- + +- For most connectors it's a no-op to call drm_connector_register/unregister + directly from driver code, drm_dev_register/unregister take care of this + already. We can remove all of them. + +- For dp drivers it's a bit more a mess, since we need the connector to be + registered when calling drm_dp_aux_register. Fix this by instead calling + drm_dp_aux_init, and moving the actual registering into a late_register + callback as recommended in the kerneldoc. + Core refactorings =================
diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c index 4c766624b20d..cd5048ceab1d 100644 --- a/drivers/gpu/drm/drm_connector.c +++ b/drivers/gpu/drm/drm_connector.c @@ -480,7 +480,10 @@ EXPORT_SYMBOL(drm_connector_cleanup); * drm_connector_register - register a connector * @connector: the connector to register * - * Register userspace interfaces for a connector + * Register userspace interfaces for a connector. Only call this for connectors + * which can be hotplugged after drm_dev_register() has been called already, + * e.g. DP MST connectors. All other connectors will be registered automatically + * when calling drm_dev_register(). * * Returns: * Zero on success, error code on failure. @@ -526,7 +529,10 @@ EXPORT_SYMBOL(drm_connector_register); * drm_connector_unregister - unregister a connector * @connector: the connector to unregister * - * Unregister userspace interfaces for a connector + * Unregister userspace interfaces for a connector. Only call this for + * connectors which have registered explicitly by calling drm_dev_register(), + * since connectors are unregistered automatically when drm_dev_unregister() is + * called. */ void drm_connector_unregister(struct drm_connector *connector) { diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index ffc68d305afe..f373798d82f6 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -1109,6 +1109,14 @@ EXPORT_SYMBOL(drm_dp_aux_init); * @aux: DisplayPort AUX channel * * Automatically calls drm_dp_aux_init() if this hasn't been done yet. + * This should only be called when the underlying &struct drm_connector is + * initialiazed already. Therefore the best place to call this is from + * &drm_connector_funcs.late_register. Not that drivers which don't follow this + * will Oops when CONFIG_DRM_DP_AUX_CHARDEV is enabled. + * + * Drivers which need to use the aux channel before that point (e.g. at driver + * load time, before drm_dev_register() has been called) need to call + * drm_dp_aux_init(). * * Returns 0 on success or a negative error code on failure. */