On Fri, Nov 21, 2025 at 02:20:48PM +0100, Ludovic Desroches wrote:
The switch from devm_kzalloc() + drm_panel_init() to devm_drm_panel_alloc() introduced a regression.
Several panel descriptors do not set connector_type. For those panels, panel_simple_probe() used to compute a connector type (currently DPI as a fallback) and pass that value to drm_panel_init(). After the conversion to devm_drm_panel_alloc(), the call unconditionally used desc->connector_type instead, ignoring the computed fallback and potentially passing DRM_MODE_CONNECTOR_Unknown, which drm_panel_bridge_add() does not allow.
Move the connector_type validation / fallback logic before the devm_drm_panel_alloc() call and pass the computed connector_type to devm_drm_panel_alloc(), so panels without an explicit connector_type once again get the DPI default.
Signed-off-by: Ludovic Desroches ludovic.desroches@microchip.com Fixes: de04bb0089a9 ("drm/panel/panel-simple: Use the new allocation in place of devm_kzalloc()")
Hi,
I am not sure whether this regression has already been reported or addressed. If it has, please feel free to drop this patch.
Would it be better to fix those panels instead? In the end, the panel usually has only one bus.
drivers/gpu/drm/panel/panel-simple.c | 86 ++++++++++++++++++------------------ 1 file changed, 43 insertions(+), 43 deletions(-)