Revert "drm/bridge: Add a drm_bridge_state object"

This reverts commit 6ed7e962 ("drm/bridge: Add a drm_bridge_state
object") which introduced a circular dependency between drm.ko and
drm_kms_helper.ko. Looks like the helper/core split is not appropriate
and fixing that is not simple.
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200107185807.606999-6-boris.brezillon@collabora.com

drivers/gpu/drm/drm_atomic.c

@@ -30,7 +30,6 @@
 
 #include <drm/drm_atomic.h>
 #include <drm/drm_atomic_uapi.h>
-#include <drm/drm_bridge.h>
 #include <drm/drm_debugfs.h>
 #include <drm/drm_device.h>
 #include <drm/drm_drv.h>
@@ -1018,44 +1017,6 @@ static void drm_atomic_connector_print_state(struct drm_printer *p,
 		connector->funcs->atomic_print_state(p, state);
 }
 
-/**
- * drm_atomic_add_encoder_bridges - add bridges attached to an encoder
- * @state: atomic state
- * @encoder: DRM encoder
- *
- * This function adds all bridges attached to @encoder. This is needed to add
- * bridge states to @state and make them available when
- * &bridge_funcs.atomic_{check,pre_enable,enable,disable_post_disable}() are
- * called
- *
- * Returns:
- * 0 on success or can fail with -EDEADLK or -ENOMEM. When the error is EDEADLK
- * then the w/w mutex code has detected a deadlock and the entire atomic
- * sequence must be restarted. All other errors are fatal.
- */
-int
-drm_atomic_add_encoder_bridges(struct drm_atomic_state *state,
-			       struct drm_encoder *encoder)
-{
-	struct drm_bridge_state *bridge_state;
-	struct drm_bridge *bridge;
-
-	if (!encoder)
-		return 0;
-
-	DRM_DEBUG_ATOMIC("Adding all bridges for [encoder:%d:%s] to %p\n",
-			 encoder->base.id, encoder->name, state);
-
-	drm_for_each_bridge_in_chain(encoder, bridge) {
-		bridge_state = drm_atomic_get_bridge_state(state, bridge);
-		if (IS_ERR(bridge_state))
-			return PTR_ERR(bridge_state);
-	}
-
-	return 0;
-}
-EXPORT_SYMBOL(drm_atomic_add_encoder_bridges);
-
 /**
  * drm_atomic_add_affected_connectors - add connectors for CRTC
  * @state: atomic state

drivers/gpu/drm/drm_atomic_helper.c

@@ -730,26 +730,6 @@ drm_atomic_helper_check_modeset(struct drm_device *dev,
 			return ret;
 	}
 
-	/*
-	 * Iterate over all connectors again, and add all affected bridges to
-	 * the state.
-	 */
-	for_each_oldnew_connector_in_state(state, connector,
-					   old_connector_state,
-					   new_connector_state, i) {
-		struct drm_encoder *encoder;
-
-		encoder = old_connector_state->best_encoder;
-		ret = drm_atomic_add_encoder_bridges(state, encoder);
-		if (ret)
-			return ret;
-
-		encoder = new_connector_state->best_encoder;
-		ret = drm_atomic_add_encoder_bridges(state, encoder);
-		if (ret)
-			return ret;
-	}
-
 	ret = mode_valid(state);
 	if (ret)
 		return ret;

drivers/gpu/drm/drm_bridge.c

@@ -25,7 +25,6 @@
 #include <linux/module.h>
 #include <linux/mutex.h>
 
-#include <drm/drm_atomic_state_helper.h>
 #include <drm/drm_bridge.h>
 #include <drm/drm_encoder.h>
 
@@ -90,74 +89,6 @@ void drm_bridge_remove(struct drm_bridge *bridge)
 }
 EXPORT_SYMBOL(drm_bridge_remove);
 
-static struct drm_bridge_state *
-drm_atomic_default_bridge_duplicate_state(struct drm_bridge *bridge)
-{
-	struct drm_bridge_state *new;
-
-	if (WARN_ON(!bridge->base.state))
-		return NULL;
-
-	new = kzalloc(sizeof(*new), GFP_KERNEL);
-	if (new)
-		__drm_atomic_helper_bridge_duplicate_state(bridge, new);
-
-	return new;
-}
-
-static struct drm_private_state *
-drm_bridge_atomic_duplicate_priv_state(struct drm_private_obj *obj)
-{
-	struct drm_bridge *bridge = drm_priv_to_bridge(obj);
-	struct drm_bridge_state *state;
-
-	if (bridge->funcs->atomic_duplicate_state)
-		state = bridge->funcs->atomic_duplicate_state(bridge);
-	else
-		state = drm_atomic_default_bridge_duplicate_state(bridge);
-
-	return state ? &state->base : NULL;
-}
-
-static void
-drm_atomic_default_bridge_destroy_state(struct drm_bridge *bridge,
-					struct drm_bridge_state *state)
-{
-	/* Just a simple kfree() for now */
-	kfree(state);
-}
-
-static void
-drm_bridge_atomic_destroy_priv_state(struct drm_private_obj *obj,
-				     struct drm_private_state *s)
-{
-	struct drm_bridge_state *state = drm_priv_to_bridge_state(s);
-	struct drm_bridge *bridge = drm_priv_to_bridge(obj);
-
-	if (bridge->funcs->atomic_destroy_state)
-		bridge->funcs->atomic_destroy_state(bridge, state);
-	else
-		drm_atomic_default_bridge_destroy_state(bridge, state);
-}
-
-static const struct drm_private_state_funcs drm_bridge_priv_state_funcs = {
-	.atomic_duplicate_state = drm_bridge_atomic_duplicate_priv_state,
-	.atomic_destroy_state = drm_bridge_atomic_destroy_priv_state,
-};
-
-static struct drm_bridge_state *
-drm_atomic_default_bridge_reset(struct drm_bridge *bridge)
-{
-	struct drm_bridge_state *bridge_state;
-
-	bridge_state = kzalloc(sizeof(*bridge_state), GFP_KERNEL);
-	if (!bridge_state)
-		return ERR_PTR(-ENOMEM);
-
-	__drm_atomic_helper_bridge_reset(bridge, bridge_state);
-	return bridge_state;
-}
-
 /**
  * drm_bridge_attach - attach the bridge to an encoder's chain
  *
@@ -183,7 +114,6 @@ drm_atomic_default_bridge_reset(struct drm_bridge *bridge)
 int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge,
 		      struct drm_bridge *previous)
 {
-	struct drm_bridge_state *state;
 	int ret;
 
 	if (!encoder || !bridge)
@@ -205,35 +135,15 @@ int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge,
 
 	if (bridge->funcs->attach) {
 		ret = bridge->funcs->attach(bridge);
-		if (ret < 0)
-			goto err_reset_bridge;
+		if (ret < 0) {
+			list_del(&bridge->chain_node);
+			bridge->dev = NULL;
+			bridge->encoder = NULL;
+			return ret;
 		}
-
-	if (bridge->funcs->atomic_reset)
-		state = bridge->funcs->atomic_reset(bridge);
-	else
-		state = drm_atomic_default_bridge_reset(bridge);
-
-	if (IS_ERR(state)) {
-		ret = PTR_ERR(state);
-		goto err_detach_bridge;
 	}
 
-	drm_atomic_private_obj_init(bridge->dev, &bridge->base,
-				    &state->base,
-				    &drm_bridge_priv_state_funcs);
-
 	return 0;
-
-err_detach_bridge:
-	if (bridge->funcs->detach)
-		bridge->funcs->detach(bridge);
-
-err_reset_bridge:
-	bridge->dev = NULL;
-	bridge->encoder = NULL;
-	list_del(&bridge->chain_node);
-	return ret;
 }
 EXPORT_SYMBOL(drm_bridge_attach);
 
@@ -245,8 +155,6 @@ void drm_bridge_detach(struct drm_bridge *bridge)
 	if (WARN_ON(!bridge->dev))
 		return;
 
-	drm_atomic_private_obj_fini(&bridge->base);
-
 	if (bridge->funcs->detach)
 		bridge->funcs->detach(bridge);
 
@@ -608,41 +516,6 @@ void drm_atomic_bridge_chain_enable(struct drm_bridge *bridge,
 }
 EXPORT_SYMBOL(drm_atomic_bridge_chain_enable);
 
-/**
- * __drm_atomic_helper_bridge_reset() - Initialize a bridge state to its
- *					default
- * @bridge: the bridge this state is refers to
- * @state: bridge state to initialize
- *
- * Initialize the bridge state to default values. This is meant to be* called
- * by the bridge &drm_plane_funcs.reset hook for bridges that subclass the
- * bridge state.
- */
-void __drm_atomic_helper_bridge_reset(struct drm_bridge *bridge,
-				      struct drm_bridge_state *state)
-{
-	memset(state, 0, sizeof(*state));
-	state->bridge = bridge;
-}
-EXPORT_SYMBOL(__drm_atomic_helper_bridge_reset);
-
-/**
- * __drm_atomic_helper_bridge_duplicate_state() - Copy atomic bridge state
- * @bridge: bridge object
- * @state: atomic bridge state
- *
- * Copies atomic state from a bridge's current state and resets inferred values.
- * This is useful for drivers that subclass the bridge state.
- */
-void __drm_atomic_helper_bridge_duplicate_state(struct drm_bridge *bridge,
-						struct drm_bridge_state *state)
-{
-	__drm_atomic_helper_private_obj_duplicate_state(&bridge->base,
-							&state->base);
-	state->bridge = bridge;
-}
-EXPORT_SYMBOL(__drm_atomic_helper_bridge_duplicate_state);
-
 #ifdef CONFIG_OF
 /**
  * of_drm_find_bridge - find the bridge corresponding to the device node in

include/drm/drm_atomic.h

@@ -669,9 +669,6 @@ __drm_atomic_get_current_plane_state(struct drm_atomic_state *state,
 	return plane->state;
 }
 
-int __must_check
-drm_atomic_add_encoder_bridges(struct drm_atomic_state *state,
-			       struct drm_encoder *encoder);
 int __must_check
 drm_atomic_add_affected_connectors(struct drm_atomic_state *state,
 				   struct drm_crtc *crtc);

include/drm/drm_bridge.h

@@ -25,8 +25,6 @@
 
 #include <linux/list.h>
 #include <linux/ctype.h>
-
-#include <drm/drm_atomic.h>
 #include <drm/drm_encoder.h>
 #include <drm/drm_mode_object.h>
 #include <drm/drm_modes.h>
@@ -35,23 +33,6 @@ struct drm_bridge;
 struct drm_bridge_timings;
 struct drm_panel;
 
-/**
- * struct drm_bridge_state - Atomic bridge state object
- * @base: inherit from &drm_private_state
- * @bridge: the bridge this state refers to
- */
-struct drm_bridge_state {
-	struct drm_private_state base;
-
-	struct drm_bridge *bridge;
-};
-
-static inline struct drm_bridge_state *
-drm_priv_to_bridge_state(struct drm_private_state *priv)
-{
-	return container_of(priv, struct drm_bridge_state, base);
-}
-
 /**
  * struct drm_bridge_funcs - drm_bridge control functions
  */
@@ -357,49 +338,6 @@ struct drm_bridge_funcs {
 	 */
 	void (*atomic_post_disable)(struct drm_bridge *bridge,
 				    struct drm_atomic_state *old_state);
-
-	/**
-	 * @atomic_duplicate_state:
-	 *
-	 * Duplicate the current bridge state object (which is guaranteed to be
-	 * non-NULL).
-	 *
-	 * The atomic_duplicate_state() is optional. When not implemented the
-	 * core allocates a drm_bridge_state object and calls
-	 * &__drm_atomic_helper_bridge_duplicate_state() to initialize it.
-	 *
-	 * RETURNS:
-	 * A valid drm_bridge_state object or NULL if the allocation fails.
-	 */
-	struct drm_bridge_state *(*atomic_duplicate_state)(struct drm_bridge *bridge);
-
-	/**
-	 * @atomic_destroy_state:
-	 *
-	 * Destroy a bridge state object previously allocated by
-	 * &drm_bridge_funcs.atomic_duplicate_state().
-	 *
-	 * The atomic_destroy_state hook is optional. When not implemented the
-	 * core calls kfree() on the state.
-	 */
-	void (*atomic_destroy_state)(struct drm_bridge *bridge,
-				     struct drm_bridge_state *state);
-
-	/**
-	 * @atomic_reset:
-	 *
-	 * Reset the bridge to a predefined state (or retrieve its current
-	 * state) and return a &drm_bridge_state object matching this state.
-	 * This function is called at attach time.
-	 *
-	 * The atomic_reset hook is optional. When not implemented the core
-	 * allocates a new state and calls &__drm_atomic_helper_bridge_reset().
-	 *
-	 * RETURNS:
-	 * A valid drm_bridge_state object in case of success, an ERR_PTR()
-	 * giving the reason of the failure otherwise.
-	 */
-	struct drm_bridge_state *(*atomic_reset)(struct drm_bridge *bridge);
 };
 
 /**
@@ -442,8 +380,6 @@ struct drm_bridge_timings {
  * struct drm_bridge - central DRM bridge control structure
  */
 struct drm_bridge {
-	/** @base: inherit from &drm_private_object */
-	struct drm_private_obj base;
 	/** @dev: DRM device this bridge belongs to */
 	struct drm_device *dev;
 	/** @encoder: encoder to which this bridge is connected */
@@ -468,12 +404,6 @@ struct drm_bridge {
 	void *driver_private;
 };
 
-static inline struct drm_bridge *
-drm_priv_to_bridge(struct drm_private_obj *priv)
-{
-	return container_of(priv, struct drm_bridge, base);
-}
-
 void drm_bridge_add(struct drm_bridge *bridge);
 void drm_bridge_remove(struct drm_bridge *bridge);
 struct drm_bridge *of_drm_find_bridge(struct device_node *np);
@@ -561,50 +491,6 @@ void drm_atomic_bridge_chain_pre_enable(struct drm_bridge *bridge,
 void drm_atomic_bridge_chain_enable(struct drm_bridge *bridge,
 				    struct drm_atomic_state *state);
 
-void __drm_atomic_helper_bridge_reset(struct drm_bridge *bridge,
-				      struct drm_bridge_state *state);
-void __drm_atomic_helper_bridge_duplicate_state(struct drm_bridge *bridge,
-						struct drm_bridge_state *new);
-
-static inline struct drm_bridge_state *
-drm_atomic_get_bridge_state(struct drm_atomic_state *state,
-			    struct drm_bridge *bridge)
-{
-	struct drm_private_state *obj_state;
-
-	obj_state = drm_atomic_get_private_obj_state(state, &bridge->base);
-	if (IS_ERR(obj_state))
-		return ERR_CAST(obj_state);
-
-	return drm_priv_to_bridge_state(obj_state);
-}
-
-static inline struct drm_bridge_state *
-drm_atomic_get_old_bridge_state(struct drm_atomic_state *state,
-				struct drm_bridge *bridge)
-{
-	struct drm_private_state *obj_state;
-
-	obj_state = drm_atomic_get_old_private_obj_state(state, &bridge->base);
-	if (!obj_state)
-		return NULL;
-
-	return drm_priv_to_bridge_state(obj_state);
-}
-
-static inline struct drm_bridge_state *
-drm_atomic_get_new_bridge_state(struct drm_atomic_state *state,
-				struct drm_bridge *bridge)
-{
-	struct drm_private_state *obj_state;
-
-	obj_state = drm_atomic_get_new_private_obj_state(state, &bridge->base);
-	if (!obj_state)
-		return NULL;
-
-	return drm_priv_to_bridge_state(obj_state);
-}
-
 #ifdef CONFIG_DRM_PANEL_BRIDGE
 struct drm_bridge *drm_panel_bridge_add(struct drm_panel *panel);
 struct drm_bridge *drm_panel_bridge_add_typed(struct drm_panel *panel,