2 files changed, 30 insertions, 3 deletions

diff --git a/drivers/clk/mediatek/clk-mux.c b/drivers/clk/mediatek/clk-mux.c
index 9370bebca7f8..b0c61709bacc 100644
--- a/drivers/clk/mediatek/clk-mux.c
+++ b/drivers/clk/mediatek/clk-mux.c
@@ -20,9 +20,33 @@ static inline struct mtk_clk_mux *to_mtk_clk_mux(struct clk_hw *hw)
 static int mtk_clk_mux_enable_setclr(struct clk_hw *hw)
 {
 	struct mtk_clk_mux *mux = to_mtk_clk_mux(hw);
+	unsigned long flags = 0;
 
-	return regmap_write(mux->regmap, mux->data->clr_ofs,
-			BIT(mux->data->gate_shift));
+	if (mux->lock)
+		spin_lock_irqsave(mux->lock, flags);
+	else
+		__acquire(mux->lock);
+
+	regmap_write(mux->regmap, mux->data->clr_ofs,
+		     BIT(mux->data->gate_shift));
+
+	/*
+	 * If the parent has been changed when the clock was disabled, it will
+	 * not be effective yet. Set the update bit to ensure the mux gets
+	 * updated.
+	 */
+	if (mux->reparent && mux->data->upd_shift >= 0) {
+		regmap_write(mux->regmap, mux->data->upd_ofs,
+			     BIT(mux->data->upd_shift));
+		mux->reparent = false;
+	}
+
+	if (mux->lock)
+		spin_unlock_irqrestore(mux->lock, flags);
+	else
+		__release(mux->lock);
+
+	return 0;
 }
 
 static void mtk_clk_mux_disable_setclr(struct clk_hw *hw)
@@ -77,9 +101,11 @@ static int mtk_clk_mux_set_parent_setclr_lock(struct clk_hw *hw, u8 index)
 		regmap_write(mux->regmap, mux->data->set_ofs,
 				index << mux->data->mux_shift);
 
-		if (mux->data->upd_shift >= 0)
+		if (mux->data->upd_shift >= 0) {
 			regmap_write(mux->regmap, mux->data->upd_ofs,
 					BIT(mux->data->upd_shift));
+			mux->reparent = true;
+		}
 	}
 
 	if (mux->lock)
diff --git a/drivers/clk/mediatek/clk-mux.h b/drivers/clk/mediatek/clk-mux.h
index 15c62366ba9a..f1946161ade1 100644
--- a/drivers/clk/mediatek/clk-mux.h
+++ b/drivers/clk/mediatek/clk-mux.h
@@ -14,6 +14,7 @@ struct mtk_clk_mux {
 	struct regmap *regmap;
 	const struct mtk_mux *data;
 	spinlock_t *lock;
+	bool reparent;
 };
 
 struct mtk_mux {