Revert "drm/bridge: Introduce pre_enable_upstream_first to alter bridge init order"

This reverts commit 52fa9a4.

Author: popcornmix

drivers/gpu/drm/drm_bridge.c

@@ -547,15 +547,20 @@ EXPORT_SYMBOL(drm_bridge_chain_disable);
  * encoder chain, starting from the first bridge to the last. These are called
  * after completing the encoder's prepare op.
  *
- * If a bridge sets @pre_enable_upstream_first, then the @post_disable for that
- * bridge will be called before the previous one to reverse the @pre_enable
- * calling direction.
- *
  * Note: the bridge passed should be the one closest to the encoder
  */
 void drm_bridge_chain_post_disable(struct drm_bridge *bridge)
 {
-	drm_atomic_bridge_chain_post_disable(bridge, NULL);
+	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);
+	}
 }
 EXPORT_SYMBOL(drm_bridge_chain_post_disable);
 
@@ -597,14 +602,24 @@ EXPORT_SYMBOL(drm_bridge_chain_mode_set);
  * chain, starting from the last bridge to the first. These are called
  * before calling the encoder's commit op.
  *
- * If a bridge sets @pre_enable_upstream_first, then the @pre_enable for the
- * previous bridge will be called before @pre_enable of this bridge.
- *
  * Note: the bridge passed should be the one closest to the encoder
  */
 void drm_bridge_chain_pre_enable(struct drm_bridge *bridge)
 {
-	drm_atomic_bridge_chain_pre_enable(bridge, NULL);
+	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;
+	}
 }
 EXPORT_SYMBOL(drm_bridge_chain_pre_enable);
 
@@ -676,25 +691,6 @@ void drm_atomic_bridge_chain_disable(struct drm_bridge *bridge,
 }
 EXPORT_SYMBOL(drm_atomic_bridge_chain_disable);
 
-static void drm_atomic_bridge_call_post_disable(struct drm_bridge *bridge,
-						struct drm_atomic_state *old_state)
-{
-	if (old_state && bridge->funcs->atomic_post_disable) {
-		struct drm_bridge_state *old_bridge_state;
-
-		old_bridge_state =
-			drm_atomic_get_old_bridge_state(old_state,
-							bridge);
-		if (WARN_ON(!old_bridge_state))
-			return;
-
-		bridge->funcs->atomic_post_disable(bridge,
-						   old_bridge_state);
-	} else if (bridge->funcs->post_disable) {
-		bridge->funcs->post_disable(bridge);
-	}
-}
-
 /**
  * drm_atomic_bridge_chain_post_disable - cleans up after disabling all bridges
  *					  in the encoder chain
@@ -705,85 +701,37 @@ static void drm_atomic_bridge_call_post_disable(struct drm_bridge *bridge,
  * &drm_bridge_funcs.post_disable) op for all the bridges in the encoder chain,
  * starting from the first bridge to the last. These are called after completing
  * &drm_encoder_helper_funcs.atomic_disable
- * If a bridge sets @pre_enable_upstream_first, then the @post_disable for that
- * bridge will be called before the previous one to reverse the @pre_enable
- * calling direction.
  *
  * Note: the bridge passed should be the one closest to the encoder
  */
 void drm_atomic_bridge_chain_post_disable(struct drm_bridge *bridge,
 					  struct drm_atomic_state *old_state)
 {
 	struct drm_encoder *encoder;
-	struct drm_bridge *next, *limit;
 
 	if (!bridge)
 		return;
 
 	encoder = bridge->encoder;
-
 	list_for_each_entry_from(bridge, &encoder->bridge_chain, chain_node) {
-		limit = NULL;
-
-		if (!list_is_last(&bridge->chain_node, &encoder->bridge_chain)) {
-			next = list_next_entry(bridge, chain_node);
-
-			if (next->pre_enable_upstream_first) {
-				/* Downstream bridge had requested that upstream
-				 * was enabled first, so disabled last
-				 */
-				limit = next;
-
-				/* Find the next bridge that has NOT requested
-				 * upstream to be enabled first / disabled last
-				 */
-				list_for_each_entry_from(next, &encoder->bridge_chain,
-							 chain_node) {
-					if (next->pre_enable_upstream_first) {
-						next = list_prev_entry(next, chain_node);
-						limit = next;
-						break;
-					}
-				}
-
-				/* Call these bridges in reverse order */
-				list_for_each_entry_from_reverse(next, &encoder->bridge_chain,
-								 chain_node) {
-					if (next == bridge)
-						break;
-
-					drm_atomic_bridge_call_post_disable(next,
-									    old_state);
-				}
-			}
-		}
+		if (bridge->funcs->atomic_post_disable) {
+			struct drm_bridge_state *old_bridge_state;
 
-		drm_atomic_bridge_call_post_disable(bridge, old_state);
+			old_bridge_state =
+				drm_atomic_get_old_bridge_state(old_state,
+								bridge);
+			if (WARN_ON(!old_bridge_state))
+				return;
 
-		if (limit)
-			bridge = limit;
+			bridge->funcs->atomic_post_disable(bridge,
+							   old_bridge_state);
+		} else if (bridge->funcs->post_disable) {
+			bridge->funcs->post_disable(bridge);
+		}
 	}
 }
 EXPORT_SYMBOL(drm_atomic_bridge_chain_post_disable);
 
-static void drm_atomic_bridge_call_pre_enable(struct drm_bridge *bridge,
-					      struct drm_atomic_state *old_state)
-{
-	if (old_state && bridge->funcs->atomic_pre_enable) {
-		struct drm_bridge_state *old_bridge_state;
-
-		old_bridge_state =
-			drm_atomic_get_old_bridge_state(old_state,
-							bridge);
-		if (WARN_ON(!old_bridge_state))
-			return;
-
-		bridge->funcs->atomic_pre_enable(bridge, old_bridge_state);
-	} else if (bridge->funcs->pre_enable) {
-		bridge->funcs->pre_enable(bridge);
-	}
-}
-
 /**
  * drm_atomic_bridge_chain_pre_enable - prepares for enabling all bridges in
  *					the encoder chain
@@ -795,61 +743,32 @@ static void drm_atomic_bridge_call_pre_enable(struct drm_bridge *bridge,
  * starting from the last bridge to the first. These are called before calling
  * &drm_encoder_helper_funcs.atomic_enable
  *
- * If a bridge sets @pre_enable_upstream_first, then the pre_enable for the
- * upstream bridge will be called before pre_enable of this bridge.
- *
  * Note: the bridge passed should be the one closest to the encoder
  */
 void drm_atomic_bridge_chain_pre_enable(struct drm_bridge *bridge,
 					struct drm_atomic_state *old_state)
 {
 	struct drm_encoder *encoder;
-	struct drm_bridge *iter, *next, *limit;
+	struct drm_bridge *iter;
 
 	if (!bridge)
 		return;
 
 	encoder = bridge->encoder;
-
 	list_for_each_entry_reverse(iter, &encoder->bridge_chain, chain_node) {
-		if (iter->pre_enable_upstream_first) {
-			next = iter;
-			limit = bridge;
-			list_for_each_entry_from_reverse(next,
-							 &encoder->bridge_chain,
-							 chain_node) {
-				if (next == bridge)
-					break;
-
-				if (!next->pre_enable_upstream_first) {
-					/* Found first bridge that does NOT
-					 * request upstream to be enabled first
-					 */
-					limit = list_prev_entry(next, chain_node);
-					break;
-				}
-			}
-
-			list_for_each_entry_from(next, &encoder->bridge_chain, chain_node) {
-				/* Call requested upstream bridge pre_enable
-				 * in order.
-				 */
-				if (next == iter)
-					/* At the first bridgge to request upstream
-					 * bridges called first.
-					 */
-					break;
-
-				drm_atomic_bridge_call_pre_enable(next, old_state);
-			}
-		}
+		if (iter->funcs->atomic_pre_enable) {
+			struct drm_bridge_state *old_bridge_state;
 
-		drm_atomic_bridge_call_pre_enable(iter, old_state);
+			old_bridge_state =
+				drm_atomic_get_old_bridge_state(old_state,
+								iter);
+			if (WARN_ON(!old_bridge_state))
+				return;
 
-		if (iter->pre_enable_upstream_first)
-			/* Jump all bridges that we have already pre_enabled
-			 */
-			iter = limit;
+			iter->funcs->atomic_pre_enable(iter, old_bridge_state);
+		} else if (iter->funcs->pre_enable) {
+			iter->funcs->pre_enable(iter);
+		}
 
 		if (iter == bridge)
 			break;

include/drm/drm_bridge.h

@@ -768,14 +768,6 @@ struct drm_bridge {
 	 * modes.
 	 */
 	bool interlace_allowed;
-	/**
-	 * @pre_enable_upstream_first: The bridge requires that the upstream
-	 * bridge @pre_enable function is called before its @pre_enable,
-	 * and conversely for post_disable. This is most frequently a
-	 * requirement for DSI devices which need the host to be initialised
-	 * before the peripheral.
-	 */
-	bool pre_enable_upstream_first;
 	/**
 	 * @ddc: Associated I2C adapter for DDC access, if any.
 	 */