Panels usually call drm_connector_set_panel_orientation(), which is later than drm/kms driver calling drm_dev_register(). This leads to a WARN(). The orientation property is known earlier. For example, some panels parse the property through device tree during probe. Add an API to return the property from panel to drm/kms driver, so the drivers are able to call drm_connector_set_panel_orientation() before drm_dev_register(). Signed-off-by: Hsin-Yi Wang <hsinyi@xxxxxxxxxxxx> --- Previous discussion: https://patchwork.kernel.org/project/linux-mediatek/cover/20220530081910.3947168-1-hsinyi@xxxxxxxxxxxx/#24877477 --- drivers/gpu/drm/drm_panel.c | 8 ++++++++ include/drm/drm_panel.h | 10 ++++++++++ 2 files changed, 18 insertions(+) diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c index f634371c717a..4a512ca80673 100644 --- a/drivers/gpu/drm/drm_panel.c +++ b/drivers/gpu/drm/drm_panel.c @@ -223,6 +223,14 @@ int drm_panel_get_modes(struct drm_panel *panel, } EXPORT_SYMBOL(drm_panel_get_modes); +enum drm_panel_orientation drm_panel_get_orientation(struct drm_panel *panel) +{ + if (panel && panel->funcs && panel->funcs->get_orientation) + return panel->funcs->get_orientation(panel); + + return DRM_MODE_PANEL_ORIENTATION_UNKNOWN; +} +EXPORT_SYMBOL(drm_panel_get_orientation); #ifdef CONFIG_OF /** * of_drm_find_panel - look up a panel using a device tree node diff --git a/include/drm/drm_panel.h b/include/drm/drm_panel.h index 1ba2d424a53f..d1bd3be4bbdf 100644 --- a/include/drm/drm_panel.h +++ b/include/drm/drm_panel.h @@ -133,6 +133,15 @@ struct drm_panel_funcs { * Allows panels to create panels-specific debugfs files. */ void (*debugfs_init)(struct drm_panel *panel, struct dentry *root); + + /** + * @get_orientation: + * + * Return the panel orientation set by device tree or EDID. + * + * This function is optional. + */ + enum drm_panel_orientation (*get_orientation)(struct drm_panel *panel); }; /** @@ -195,6 +204,7 @@ int drm_panel_enable(struct drm_panel *panel); int drm_panel_disable(struct drm_panel *panel); int drm_panel_get_modes(struct drm_panel *panel, struct drm_connector *connector); +enum drm_panel_orientation drm_panel_get_orientation(struct drm_panel *panel); #if defined(CONFIG_OF) && defined(CONFIG_DRM_PANEL) struct drm_panel *of_drm_find_panel(const struct device_node *np); -- 2.36.1.255.ge46751e96f-goog