clk: qcom: regmap-mux: fix parent clock lookup

The function mux_get_parent() uses qcom_find_src_index() to find the
parent clock index, which is incorrect: qcom_find_src_index() uses src
enum for the lookup, while mux_get_parent() should use cfg field (which
corresponds to the register value). Add qcom_find_cfg_index() function
doing this kind of lookup and use it for mux parent lookup.

Fixes: df96401649 ("clk: qcom: add parent map for regmap mux")
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20211115233407.1046179-1-dmitry.baryshkov@linaro.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

drivers/clk/qcom/clk-regmap-mux.c

@@ -28,7 +28,7 @@ static u8 mux_get_parent(struct clk_hw *hw)
 	val &= mask;
 
 	if (mux->parent_map)
-		return qcom_find_src_index(hw, mux->parent_map, val);
+		return qcom_find_cfg_index(hw, mux->parent_map, val);
 
 	return val;
 }

drivers/clk/qcom/common.c

@@ -69,6 +69,18 @@ int qcom_find_src_index(struct clk_hw *hw, const struct parent_map *map, u8 src)
 }
 EXPORT_SYMBOL_GPL(qcom_find_src_index);
 
+int qcom_find_cfg_index(struct clk_hw *hw, const struct parent_map *map, u8 cfg)
+{
+	int i, num_parents = clk_hw_get_num_parents(hw);
+
+	for (i = 0; i < num_parents; i++)
+		if (cfg == map[i].cfg)
+			return i;
+
+	return -ENOENT;
+}
+EXPORT_SYMBOL_GPL(qcom_find_cfg_index);
+
 struct regmap *
 qcom_cc_map(struct platform_device *pdev, const struct qcom_cc_desc *desc)
 {

drivers/clk/qcom/common.h

@@ -49,6 +49,8 @@ extern void
 qcom_pll_set_fsm_mode(struct regmap *m, u32 reg, u8 bias_count, u8 lock_count);
 extern int qcom_find_src_index(struct clk_hw *hw, const struct parent_map *map,
 			       u8 src);
+extern int qcom_find_cfg_index(struct clk_hw *hw, const struct parent_map *map,
+			       u8 cfg);
 
 extern int qcom_cc_register_board_clk(struct device *dev, const char *path,
 				      const char *name, unsigned long rate);