ASoC: Don't reconfigure WM8350 FLL if not needed

If the requested FLL configuration is the one we're currently running
in it's at best pointless to reconfigure the FLL.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/codecs/wm8350.c

@@ -63,6 +63,8 @@ struct wm8350_data {
 	struct wm8350_jack_data hpl;
 	struct wm8350_jack_data hpr;
 	struct regulator_bulk_data supplies[ARRAY_SIZE(supply_names)];
+	int fll_freq_out;
+	int fll_freq_in;
 };
 
 static unsigned int wm8350_codec_cache_read(struct snd_soc_codec *codec,
@@ -1104,10 +1106,14 @@ static int wm8350_set_fll(struct snd_soc_dai *codec_dai,
 {
 	struct snd_soc_codec *codec = codec_dai->codec;
 	struct wm8350 *wm8350 = codec->control_data;
+	struct wm8350_data *priv = codec->private_data;
 	struct _fll_div fll_div;
 	int ret = 0;
 	u16 fll_1, fll_4;
 
+	if (freq_in == priv->fll_freq_in && freq_out == priv->fll_freq_out)
+		return 0;
+
 	/* power down FLL - we need to do this for reconfiguration */
 	wm8350_clear_bits(wm8350, WM8350_POWER_MGMT_4,
 			  WM8350_FLL_ENA | WM8350_FLL_OSC_ENA);
@@ -1142,6 +1148,9 @@ static int wm8350_set_fll(struct snd_soc_dai *codec_dai,
 	wm8350_set_bits(wm8350, WM8350_POWER_MGMT_4, WM8350_FLL_OSC_ENA);
 	wm8350_set_bits(wm8350, WM8350_POWER_MGMT_4, WM8350_FLL_ENA);
 
+	priv->fll_freq_out = freq_out;
+	priv->fll_freq_in = freq_in;
+
 	return 0;
 }