[PATCH v2 03/28] drm/atomic_state_helper: Remove memset in __drm_atomic_helper_bridge_reset()

[Maxime Ripard]

The general consensus is that reset helpers shouldn't call memset
directly because the object it initializes is supposed to have been
zeroed out.

Remove the memset call from
__drm_atomic_helper_bridge_reset() and document the expectation.

It should not have any impact on the current code base since there's
only two callers: drm_atomic_helper_bridge_reset() and
cdns-mhdp8546-core's cdns_mhdp_bridge_atomic_reset(), both allocating
the object using kzalloc_obj().

Suggested-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
Signed-off-by: Maxime Ripard <mripard@xxxxxxxxxx>
---
 drivers/gpu/drm/drm_atomic_state_helper.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_atomic_state_helper.c b/drivers/gpu/drm/drm_atomic_state_helper.c
index c7eb3ce8c282..1a6f55329fee 100644
--- a/drivers/gpu/drm/drm_atomic_state_helper.c
+++ b/drivers/gpu/drm/drm_atomic_state_helper.c
@@ -952,15 +952,16 @@ EXPORT_SYMBOL(drm_atomic_helper_bridge_destroy_state);
  * @state: bridge state to initialize
  *
  * Initializes the bridge state to default values. This is meant to be called
  * by the bridge &drm_bridge_funcs.atomic_reset hook for bridges that subclass
  * the bridge state.
+ *
+ * The object @state points to is assumed to have been initialized to zero.
  */
 void __drm_atomic_helper_bridge_reset(struct drm_bridge *bridge,
 				      struct drm_bridge_state *state)
 {
-	memset(state, 0, sizeof(*state));
 	__drm_atomic_helper_private_obj_create_state(&bridge->base, &state->base);
 	state->bridge = bridge;
 }
 EXPORT_SYMBOL(__drm_atomic_helper_bridge_reset);
 

-- 
2.53.0