drm/drm_of: Move drm_of_panel_bridge_remove_function into header.

Core drm shouldn't depend on anything in drm-kms-helper, or the drm
module will fail to load.

insmod drm fails with
[ 6087.674390] drm: Unknown symbol drm_panel_bridge_remove (err 0)

which is defined in drm_kms_helper.ko

This call was added by commit c70087e8f16f ("drm/drm_of: add
drm_of_panel_bridge_remove function"), and the fix is defining it in the
drm_of.h header, to break the circular dependency.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/8f95e623-9480-97dc-2414-77086d8aa49d@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@intel.com> #irc
Fixes: c70087e8f16f ("drm/drm_of: add drm_of_panel_bridge_remove function")
Acked-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>

drivers/gpu/drm/drm_of.c

@@ -262,36 +262,3 @@ int drm_of_find_panel_or_bridge(const struct device_node *np,
 	return ret;
 }
 EXPORT_SYMBOL_GPL(drm_of_find_panel_or_bridge);
-
-#ifdef CONFIG_DRM_PANEL_BRIDGE
-/*
- * drm_of_panel_bridge_remove - remove panel bridge
- * @np: device tree node containing panel bridge output ports
- *
- * Remove the panel bridge of a given DT node's port and endpoint number
- *
- * Returns zero if successful, or one of the standard error codes if it fails.
- */
-int drm_of_panel_bridge_remove(const struct device_node *np,
-			       int port, int endpoint)
-{
-	struct drm_bridge *bridge;
-	struct device_node *remote;
-
-	remote = of_graph_get_remote_node(np, port, endpoint);
-	if (!remote)
-		return -ENODEV;
-
-	bridge = of_drm_find_bridge(remote);
-	drm_panel_bridge_remove(bridge);
-
-	return 0;
-}
-#else
-int drm_of_panel_bridge_remove(const struct device_node *np,
-			       int port, int endpoint)
-{
-	return -EINVAL;
-}
-#endif
-EXPORT_SYMBOL_GPL(drm_of_panel_bridge_remove);

include/drm/drm_of.h

@@ -2,6 +2,9 @@
 #define __DRM_OF_H__
 
 #include <linux/of_graph.h>
+#if IS_ENABLED(CONFIG_OF) && IS_ENABLED(CONFIG_DRM_PANEL_BRIDGE)
+#include <drm/drm_bridge.h>
+#endif
 
 struct component_master_ops;
 struct component_match;
@@ -29,8 +32,6 @@ int drm_of_find_panel_or_bridge(const struct device_node *np,
 				int port, int endpoint,
 				struct drm_panel **panel,
 				struct drm_bridge **bridge);
-int drm_of_panel_bridge_remove(const struct device_node *np,
-			       int port, int endpoint);
 #else
 static inline uint32_t drm_of_find_possible_crtcs(struct drm_device *dev,
 						  struct device_node *port)
@@ -67,13 +68,35 @@ static inline int drm_of_find_panel_or_bridge(const struct device_node *np,
 {
 	return -EINVAL;
 }
+#endif
 
+/*
+ * drm_of_panel_bridge_remove - remove panel bridge
+ * @np: device tree node containing panel bridge output ports
+ *
+ * Remove the panel bridge of a given DT node's port and endpoint number
+ *
+ * Returns zero if successful, or one of the standard error codes if it fails.
+ */
 static inline int drm_of_panel_bridge_remove(const struct device_node *np,
 					     int port, int endpoint)
 {
+#if IS_ENABLED(CONFIG_OF) && IS_ENABLED(CONFIG_DRM_PANEL_BRIDGE)
+	struct drm_bridge *bridge;
+	struct device_node *remote;
+
+	remote = of_graph_get_remote_node(np, port, endpoint);
+	if (!remote)
+		return -ENODEV;
+
+	bridge = of_drm_find_bridge(remote);
+	drm_panel_bridge_remove(bridge);
+
+	return 0;
+#else
 	return -EINVAL;
-}
 #endif
+}
 
 static inline int drm_of_encoder_active_endpoint_id(struct device_node *node,
 						    struct drm_encoder *encoder)