Panels usually call drm_connector_set_panel_orientation(), which is later than drm/kms driver calling drm_dev_register(). This leads to a WARN()[1].
The orientation property is known earlier. For example, some panels parse the property through device tree during probe.
The series add a panel API drm_connector_set_orientation_from_panel() for drm/kms drivers. The drivers can call the API to set panel's orientation before drm_dev_register().
Panel needs to implement .get_orientation callback to return the property.
[1] https://patchwork.kernel.org/project/linux-mediatek/patch/20220530081910.394...
v4 of this series is "Add a panel API to return panel orientation": https://lore.kernel.org/lkml/20220606152431.1889185-1-hsinyi@chromium.org/
Hsin-Yi Wang (8): drm/panel: Add an API to allow drm to set orientation from panel drm/panel: boe-tv101wum-nl6: Implement .get_orientation callback drm/panel: panel-edp: Implement .get_orientation callback drm/panel: lvds: Implement .get_orientation callback drm/panel: panel-simple: Implement .get_orientation callback drm/panel: ili9881c: Implement .get_orientation callback drm/panel: elida-kd35t133: Implement .get_orientation callback drm/mediatek: Config orientation property if panel provides it
drivers/gpu/drm/drm_connector.c | 32 +++++++++++++++++++ drivers/gpu/drm/mediatek/mtk_dsi.c | 15 +++++++++ .../gpu/drm/panel/panel-boe-tv101wum-nl6.c | 12 +++++++ drivers/gpu/drm/panel/panel-edp.c | 13 +++++++- drivers/gpu/drm/panel/panel-elida-kd35t133.c | 12 +++++++ drivers/gpu/drm/panel/panel-ilitek-ili9881c.c | 12 +++++++ drivers/gpu/drm/panel/panel-lvds.c | 13 ++++++++ drivers/gpu/drm/panel/panel-simple.c | 14 +++++++- include/drm/drm_connector.h | 4 +++ include/drm/drm_panel.h | 9 ++++++ 10 files changed, 134 insertions(+), 2 deletions(-)