[PATCH V2 1/4] drm/bridge: Remove duplication from drm_bridge and drm_atomic_bridge chains

[Dave Stevenson <dave.stevenson@xxxxxxxxxxxxxxx>]

drm_bridge_chain_pre_enable is a subset of
drm_atomic_bridge_chain_pre_enable, and drm_bridge_chain_post_disable
is a subset of drm_atomic_bridge_chain_post_disable.

Change drm_bridge_chain_pre_enable and drm_bridge_chain_post_disable to
call the atomic versions with a NULL state, and ensure that atomic
calls are not made if there is no state.

Signed-off-by: Dave Stevenson <dave.stevenson@xxxxxxxxxxxxxxx>
---
 drivers/gpu/drm/drm_bridge.c | 30 ++++--------------------------
 1 file changed, 4 insertions(+), 26 deletions(-)

diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c
index c96847fc0ebc..198fd471a488 100644
--- a/drivers/gpu/drm/drm_bridge.c
+++ b/drivers/gpu/drm/drm_bridge.c
@@ -527,16 +527,7 @@ EXPORT_SYMBOL(drm_bridge_chain_disable);
  */
 void drm_bridge_chain_post_disable(struct drm_bridge *bridge)
 {
-	struct drm_encoder *encoder;
-
-	if (!bridge)
-		return;
-
-	encoder = bridge->encoder;
-	list_for_each_entry_from(bridge, &encoder->bridge_chain, chain_node) {
-		if (bridge->funcs->post_disable)
-			bridge->funcs->post_disable(bridge);
-	}
+	drm_atomic_bridge_chain_post_disable(bridge, NULL);
 }
 EXPORT_SYMBOL(drm_bridge_chain_post_disable);
 
@@ -582,20 +573,7 @@ EXPORT_SYMBOL(drm_bridge_chain_mode_set);
  */
 void drm_bridge_chain_pre_enable(struct drm_bridge *bridge)
 {
-	struct drm_encoder *encoder;
-	struct drm_bridge *iter;
-
-	if (!bridge)
-		return;
-
-	encoder = bridge->encoder;
-	list_for_each_entry_reverse(iter, &encoder->bridge_chain, chain_node) {
-		if (iter->funcs->pre_enable)
-			iter->funcs->pre_enable(iter);
-
-		if (iter == bridge)
-			break;
-	}
+	drm_atomic_bridge_chain_pre_enable(bridge, NULL);
 }
 EXPORT_SYMBOL(drm_bridge_chain_pre_enable);
 
@@ -690,7 +668,7 @@ void drm_atomic_bridge_chain_post_disable(struct drm_bridge *bridge,
 
 	encoder = bridge->encoder;
 	list_for_each_entry_from(bridge, &encoder->bridge_chain, chain_node) {
-		if (bridge->funcs->atomic_post_disable) {
+		if (old_state && bridge->funcs->atomic_post_disable) {
 			struct drm_bridge_state *old_bridge_state;
 
 			old_bridge_state =
@@ -732,7 +710,7 @@ void drm_atomic_bridge_chain_pre_enable(struct drm_bridge *bridge,
 
 	encoder = bridge->encoder;
 	list_for_each_entry_reverse(iter, &encoder->bridge_chain, chain_node) {
-		if (iter->funcs->atomic_pre_enable) {
+		if (old_state && iter->funcs->atomic_pre_enable) {
 			struct drm_bridge_state *old_bridge_state;
 
 			old_bridge_state =
-- 
2.7.4