ASoC: dmic: Fix clock parenting

In 4.16 the clock hierarchy got changed by
a5c82a09 ARM: dts: omap4: add clkctrl nodes

The fck of dmic is no longer a mux clock, it's parent is.
Signed-off-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org # 4.16+

sound/soc/omap/omap-dmic.c

@@ -281,7 +281,7 @@ static int omap_dmic_dai_trigger(struct snd_pcm_substream *substream,
 static int omap_dmic_select_fclk(struct omap_dmic *dmic, int clk_id,
 				 unsigned int freq)
 {
-	struct clk *parent_clk;
+	struct clk *parent_clk, *mux;
 	char *parent_clk_name;
 	int ret = 0;
 
@@ -329,14 +329,21 @@ static int omap_dmic_select_fclk(struct omap_dmic *dmic, int clk_id,
 		return -ENODEV;
 	}
 
+	mux = clk_get_parent(dmic->fclk);
+	if (IS_ERR(mux)) {
+		dev_err(dmic->dev, "can't get fck mux parent\n");
+		clk_put(parent_clk);
+		return -ENODEV;
+	}
+
 	mutex_lock(&dmic->mutex);
 	if (dmic->active) {
 		/* disable clock while reparenting */
 		pm_runtime_put_sync(dmic->dev);
-		ret = clk_set_parent(dmic->fclk, parent_clk);
+		ret = clk_set_parent(mux, parent_clk);
 		pm_runtime_get_sync(dmic->dev);
 	} else {
-		ret = clk_set_parent(dmic->fclk, parent_clk);
+		ret = clk_set_parent(mux, parent_clk);
 	}
 	mutex_unlock(&dmic->mutex);
 
@@ -349,6 +356,7 @@ static int omap_dmic_select_fclk(struct omap_dmic *dmic, int clk_id,
 	dmic->fclk_freq = freq;
 
 err_busy:
+	clk_put(mux);
 	clk_put(parent_clk);
 
 	return ret;