drm/i915: Extract intel_atomic_swap_state()

Pull all the state swap stuff into its own function to declutter
intel_atomic_commit() a bit.

Note that currently the state swap is spread across both
sides of the unprepare branch in intel_atomic_commit(), but
we can pull all of it ahead a bit since we bail on the first
error, and thus there is no change in behaviour from the
reordering.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231219130756.25986-4-ville.syrjala@linux.intel.comReviewed-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>

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

@@ -7320,6 +7320,23 @@ static int intel_atomic_setup_commit(struct intel_atomic_state *state, bool nonb
 	return 0;
 }
 
+static int intel_atomic_swap_state(struct intel_atomic_state *state)
+{
+	int ret;
+
+	ret = drm_atomic_helper_swap_state(&state->base, true);
+	if (ret)
+		return ret;
+
+	intel_atomic_swap_global_state(state);
+
+	intel_shared_dpll_swap_state(state);
+
+	intel_atomic_track_fbs(state);
+
+	return 0;
+}
+
 int intel_atomic_commit(struct drm_device *dev, struct drm_atomic_state *_state,
 			bool nonblock)
 {
@@ -7367,9 +7384,7 @@ int intel_atomic_commit(struct drm_device *dev, struct drm_atomic_state *_state,
 
 	ret = intel_atomic_setup_commit(state, nonblock);
 	if (!ret)
-		ret = drm_atomic_helper_swap_state(&state->base, true);
-	if (!ret)
-		intel_atomic_swap_global_state(state);
+		ret = intel_atomic_swap_state(state);
 
 	if (ret) {
 		struct intel_crtc_state *new_crtc_state;
@@ -7383,8 +7398,6 @@ int intel_atomic_commit(struct drm_device *dev, struct drm_atomic_state *_state,
 		intel_runtime_pm_put(&dev_priv->runtime_pm, state->wakeref);
 		return ret;
 	}
-	intel_shared_dpll_swap_state(state);
-	intel_atomic_track_fbs(state);
 
 	drm_atomic_state_get(&state->base);
 	INIT_WORK(&state->base.commit_work, intel_atomic_commit_work);