Having an DRM_MODE_CONNECTOR_Unknown connector type is considered bad, and drm_panel_bridge_add_typed() and derivatives are deprecated for this.
drm_panel_init() won't prevent initializing a panel with a DRM_MODE_CONNECTOR_Unknown connector type. Luckily there are no in-tree users doing it, so take this as an opportinuty to document a valid connector type must be passed. Returning an error if this rule is violated is not possible because drm_panel_init() is a void function. Add at least a warning to make any violations noticeable, especially to non-upstream drivers. Reviewed-by: Dmitry Baryshkov <dmitry.barysh...@linaro.org> Signed-off-by: Luca Ceresoli <luca.ceres...@bootlin.com> --- Changed in v7: - fix typo in commit message - rebased on v6 (applies to drm_panel, not bridge/panel.c) This patch was added in v6. --- drivers/gpu/drm/drm_panel.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c index 9940e96d35e302080c32b49154bbf19a51c0665e..c627e42a7ce70459f50eb5095fffc806ca45dabf 100644 --- a/drivers/gpu/drm/drm_panel.c +++ b/drivers/gpu/drm/drm_panel.c @@ -50,7 +50,7 @@ static LIST_HEAD(panel_list); * @dev: parent device of the panel * @funcs: panel operations * @connector_type: the connector type (DRM_MODE_CONNECTOR_*) corresponding to - * the panel interface + * the panel interface (must NOT be DRM_MODE_CONNECTOR_Unknown) * * Initialize the panel structure for subsequent registration with * drm_panel_add(). @@ -58,6 +58,9 @@ static LIST_HEAD(panel_list); void drm_panel_init(struct drm_panel *panel, struct device *dev, const struct drm_panel_funcs *funcs, int connector_type) { + if (connector_type == DRM_MODE_CONNECTOR_Unknown) + DRM_WARN("%s: %s: a valid connector type is required!\n", __func__, dev_name(dev)); + INIT_LIST_HEAD(&panel->list); INIT_LIST_HEAD(&panel->followers); mutex_init(&panel->follower_lock); -- 2.48.1