drm/i915: Polish intel_shared_dpll_swap_state()

Use swap() instead of hand rolling it in intel_shared_dpll_swap_state(),
and pass in the intel_atomic_state instead of drm_atomic_state. Makes
the code less convoluted.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190701160550.24205-3-ville.syrjala@linux.intel.comReviewed-by: Imre Deak <imre.deak@intel.com>

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

@@ -14187,7 +14187,7 @@ static int intel_atomic_commit(struct drm_device *dev,
 		return ret;
 	}
 	dev_priv->wm.distrust_bios_wm = false;
-	intel_shared_dpll_swap_state(state);
+	intel_shared_dpll_swap_state(intel_state);
 	intel_atomic_track_fbs(state);
 
 	if (intel_state->modeset) {

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

@@ -347,25 +347,20 @@ static void intel_put_dpll(struct intel_atomic_state *state,
  * i.e. it also puts the current state into @state, even though there is no
  * need for that at this moment.
  */
-void intel_shared_dpll_swap_state(struct drm_atomic_state *state)
+void intel_shared_dpll_swap_state(struct intel_atomic_state *state)
 {
-	struct drm_i915_private *dev_priv = to_i915(state->dev);
-	struct intel_shared_dpll_state *shared_dpll;
-	struct intel_shared_dpll *pll;
+	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
+	struct intel_shared_dpll_state *shared_dpll = state->shared_dpll;
 	enum intel_dpll_id i;
 
-	if (!to_intel_atomic_state(state)->dpll_set)
+	if (!state->dpll_set)
 		return;
 
-	shared_dpll = to_intel_atomic_state(state)->shared_dpll;
 	for (i = 0; i < dev_priv->num_shared_dpll; i++) {
-		struct intel_shared_dpll_state tmp;
-
-		pll = &dev_priv->shared_dplls[i];
+		struct intel_shared_dpll *pll =
+			&dev_priv->shared_dplls[i];
 
-		tmp = pll->state;
-		pll->state = shared_dpll[i];
-		shared_dpll[i] = tmp;
+		swap(pll->state, shared_dpll[i]);
 	}
 }
 

drivers/gpu/drm/i915/display/intel_dpll_mgr.h

@@ -37,7 +37,6 @@
 	(void) (&__a == &__b);			\
 	__a > __b ? (__a - __b) : (__b - __a); })
 
-struct drm_atomic_state;
 struct drm_device;
 struct drm_i915_private;
 struct intel_atomic_state;
@@ -358,7 +357,7 @@ void intel_update_active_dpll(struct intel_atomic_state *state,
 void intel_prepare_shared_dpll(const struct intel_crtc_state *crtc_state);
 void intel_enable_shared_dpll(const struct intel_crtc_state *crtc_state);
 void intel_disable_shared_dpll(const struct intel_crtc_state *crtc_state);
-void intel_shared_dpll_swap_state(struct drm_atomic_state *state);
+void intel_shared_dpll_swap_state(struct intel_atomic_state *state);
 void intel_shared_dpll_init(struct drm_device *dev);
 
 void intel_dpll_dump_hw_state(struct drm_i915_private *dev_priv,