drm/bridge: refcount last_bridge in drm_atomic_bridge_chain_select_bus_fmts()

Get a reference for the last_bridge when it is obtained and release it
using a cleanup action.

Reviewed-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20250924-b4-drm-bridge-alloc-getput-drm_atomic_bridge_chain_select_bus_fmts-v1-1-f8c2efdb783f@bootlin.com
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>

diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c
index 630b5e6594e0affad9ba48791207c7b403da5db8..53e7ece36dd940aabd1c0880f296fce7224a12ac 100644 (file)
--- a/drivers/gpu/drm/drm_bridge.c
+++ b/drivers/gpu/drm/drm_bridge.c
@@ -1086,12 +1086,12 @@ drm_atomic_bridge_chain_select_bus_fmts(struct drm_bridge *bridge,
        struct drm_encoder *encoder = bridge->encoder;
        struct drm_bridge_state *last_bridge_state;
        unsigned int i, num_out_bus_fmts = 0;
-       struct drm_bridge *last_bridge;
        u32 *out_bus_fmts;
        int ret = 0;
 
-       last_bridge = list_last_entry(&encoder->bridge_chain,
-                                     struct drm_bridge, chain_node);
+       struct drm_bridge *last_bridge __free(drm_bridge_put) =
+               drm_bridge_get(list_last_entry(&encoder->bridge_chain,
+                                              struct drm_bridge, chain_node));
        last_bridge_state = drm_atomic_get_new_bridge_state(crtc_state->state,
                                                            last_bridge);