drm/bridge/panel: Fix runtime warning on panel bridge release

Device managed panel bridge wrappers are created by calling to
drm_panel_bridge_add_typed() and registering a release handler for
clean-up when the device gets unbound.

Since the memory for this bridge is also managed and linked to the panel
device, the release function should not try to free that memory.
Moreover, the call to devm_kfree() inside drm_panel_bridge_remove() will
fail in this case and emit a warning because the panel bridge resource
is no longer on the device resources list (it has been removed from
there before the call to release handlers).

Fixes: 67022227ffb1 ("drm/bridge: Add a devm_ allocator for panel bridge.")
Signed-off-by: Adam Miotk <adam.miotk@arm.com>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240610102739.139852-1-adam.miotk@arm.com

diff --git a/drivers/gpu/drm/bridge/panel.c b/drivers/gpu/drm/bridge/panel.c
index 3250652..fe5fb08 100644 (file)
--- a/drivers/gpu/drm/bridge/panel.c
+++ b/drivers/gpu/drm/bridge/panel.c
@@ -360,9 +360,12 @@ EXPORT_SYMBOL(drm_panel_bridge_set_orientation);
 
 static void devm_drm_panel_bridge_release(struct device *dev, void *res)
 {
-       struct drm_bridge **bridge = res;
+       struct drm_bridge *bridge = *(struct drm_bridge **)res;
 
-       drm_panel_bridge_remove(*bridge);
+       if (!bridge)
+               return;
+
+       drm_bridge_remove(bridge);
 }
 
 /**