drm/mst: Fix NULL pointer dereference at drm_dp_add_payload_part2

[Why]
Commit:
- commit 5aa1dfc ("drm/mst: Refactor the flow for payload allocation/removement")
accidently overwrite the commit
- commit 54d2174 ("drm: use mgr->dev in drm_dbg_kms in drm_dp_add_payload_part2")
which cause regression.

[How]
Recover the original NULL fix and remove the unnecessary input parameter 'state' for
drm_dp_add_payload_part2().

Fixes: 5aa1dfc ("drm/mst: Refactor the flow for payload allocation/removement")
Reported-by: Leon Weiß <leon.weiss@ruhr-uni-bochum.de>
Link: https://lore.kernel.org/r/38c253ea42072cc825dc969ac4e6b9b600371cc8.camel@ruhr-uni-bochum.de/
Cc: lyude@redhat.com
Cc: imre.deak@intel.com
Cc: stable@vger.kernel.org
Cc: regressions@lists.linux.dev
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Wayne Lin <Wayne.Lin@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240307062957.2323620-1-Wayne.Lin@amd.com
(cherry picked from commit 4545614c1d8da603e57b60dd66224d81b6ffc305)

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c

@@ -363,7 +363,7 @@ void dm_helpers_dp_mst_send_payload_allocation(
 	mst_state = to_drm_dp_mst_topology_state(mst_mgr->base.state);
 	new_payload = drm_atomic_get_mst_payload_state(mst_state, aconnector->mst_output_port);
 
-	ret = drm_dp_add_payload_part2(mst_mgr, mst_state->base.state, new_payload);
+	ret = drm_dp_add_payload_part2(mst_mgr, new_payload);
 
 	if (ret) {
 		amdgpu_dm_set_mst_status(&aconnector->mst_status,

drivers/gpu/drm/display/drm_dp_mst_topology.c

@@ -3421,7 +3421,6 @@ EXPORT_SYMBOL(drm_dp_remove_payload_part2);
 /**
  * drm_dp_add_payload_part2() - Execute payload update part 2
  * @mgr: Manager to use.
- * @state: The global atomic state
  * @payload: The payload to update
  *
  * If @payload was successfully assigned a starting time slot by drm_dp_add_payload_part1(), this
@@ -3430,14 +3429,13 @@ EXPORT_SYMBOL(drm_dp_remove_payload_part2);
  * Returns: 0 on success, negative error code on failure.
  */
 int drm_dp_add_payload_part2(struct drm_dp_mst_topology_mgr *mgr,
-			     struct drm_atomic_state *state,
 			     struct drm_dp_mst_atomic_payload *payload)
 {
 	int ret = 0;
 
 	/* Skip failed payloads */
 	if (payload->payload_allocation_status != DRM_DP_MST_PAYLOAD_ALLOCATION_DFP) {
-		drm_dbg_kms(state->dev, "Part 1 of payload creation for %s failed, skipping part 2\n",
+		drm_dbg_kms(mgr->dev, "Part 1 of payload creation for %s failed, skipping part 2\n",
 			    payload->port->connector->name);
 		return -EIO;
 	}

drivers/gpu/drm/i915/display/intel_dp_mst.c

@@ -1241,7 +1241,7 @@ static void intel_mst_enable_dp(struct intel_atomic_state *state,
 	if (first_mst_stream)
 		intel_ddi_wait_for_fec_status(encoder, pipe_config, true);
 
-	drm_dp_add_payload_part2(&intel_dp->mst_mgr, &state->base,
+	drm_dp_add_payload_part2(&intel_dp->mst_mgr,
 				 drm_atomic_get_mst_payload_state(mst_state, connector->port));
 
 	if (DISPLAY_VER(dev_priv) >= 12)

drivers/gpu/drm/nouveau/dispnv50/disp.c

@@ -915,7 +915,7 @@ nv50_msto_cleanup(struct drm_atomic_state *state,
 		msto->disabled = false;
 		drm_dp_remove_payload_part2(mgr, new_mst_state, old_payload, new_payload);
 	} else if (msto->enabled) {
-		drm_dp_add_payload_part2(mgr, state, new_payload);
+		drm_dp_add_payload_part2(mgr, new_payload);
 		msto->enabled = false;
 	}
 }

include/drm/display/drm_dp_mst_helper.h

@@ -871,7 +871,6 @@ int drm_dp_add_payload_part1(struct drm_dp_mst_topology_mgr *mgr,
 			     struct drm_dp_mst_topology_state *mst_state,
 			     struct drm_dp_mst_atomic_payload *payload);
 int drm_dp_add_payload_part2(struct drm_dp_mst_topology_mgr *mgr,
-			     struct drm_atomic_state *state,
 			     struct drm_dp_mst_atomic_payload *payload);
 void drm_dp_remove_payload_part1(struct drm_dp_mst_topology_mgr *mgr,
 				 struct drm_dp_mst_topology_state *mst_state,