1 files changed, 29 insertions, 17 deletions

diff --git a/drivers/video/tegra/dc/ext/dev.c b/drivers/video/tegra/dc/ext/dev.c
index 92e42ce32ac2..8ec015cbde9b 100644
--- a/drivers/video/tegra/dc/ext/dev.c
+++ b/drivers/video/tegra/dc/ext/dev.c
@@ -274,31 +274,40 @@ static int tegra_dc_ext_set_windowattr(struct tegra_dc_ext *ext,
 	return 0;
 }
 
-static struct srcu_notifier_head tegra_dc_flip_notifier_list;
-static bool init_tegra_dc_flip_notifier_list_called;
-static int __init init_tegra_dc_flip_notifier_list(void)
+static void (*flip_callback)(void);
+static spinlock_t flip_callback_lock;
+static bool init_tegra_dc_flip_callback_called;
+
+static int __init init_tegra_dc_flip_callback(void)
 {
-	srcu_init_notifier_head(&tegra_dc_flip_notifier_list);
-	init_tegra_dc_flip_notifier_list_called = true;
+	spin_lock_init(&flip_callback_lock);
+	init_tegra_dc_flip_callback_called = true;
 	return 0;
 }
 
-pure_initcall(init_tegra_dc_flip_notifier_list);
+pure_initcall(init_tegra_dc_flip_callback);
 
-int tegra_dc_register_flip_notifier(struct notifier_block *nb)
+int tegra_dc_set_flip_callback(void (*callback)(void))
 {
-	WARN_ON(!init_tegra_dc_flip_notifier_list_called);
+	WARN_ON(!init_tegra_dc_flip_callback_called);
+
+	spin_lock(&flip_callback_lock);
+	flip_callback = callback;
+	spin_unlock(&flip_callback_lock);
 
-	return srcu_notifier_chain_register(
-			&tegra_dc_flip_notifier_list, nb);
+	return 0;
 }
-EXPORT_SYMBOL(tegra_dc_register_flip_notifier);
+EXPORT_SYMBOL(tegra_dc_set_flip_callback);
 
-int tegra_dc_unregister_flip_notifier(struct notifier_block *nb)
+int tegra_dc_unset_flip_callback()
 {
-	return srcu_notifier_chain_unregister(&tegra_dc_flip_notifier_list, nb);
+	spin_lock(&flip_callback_lock);
+	flip_callback = NULL;
+	spin_unlock(&flip_callback_lock);
+
+	return 0;
 }
-EXPORT_SYMBOL(tegra_dc_unregister_flip_notifier);
+EXPORT_SYMBOL(tegra_dc_unset_flip_callback);
 
 static void tegra_dc_ext_flip_worker(struct work_struct *work)
 {
@@ -353,9 +362,12 @@ static void tegra_dc_ext_flip_worker(struct work_struct *work)
 		tegra_dc_update_windows(wins, nr_win);
 		/* TODO: implement swapinterval here */
 		tegra_dc_sync_windows(wins, nr_win);
-		if (!tegra_dc_has_multiple_dc())
-			srcu_notifier_call_chain(&tegra_dc_flip_notifier_list,
-						 1UL, NULL);
+		if (!tegra_dc_has_multiple_dc()) {
+			spin_lock(&flip_callback_lock);
+			if (flip_callback)
+				flip_callback();
+			spin_unlock(&flip_callback_lock);
+		}
 	}
 
 	for (i = 0; i < DC_N_WINDOWS; i++) {