[PATCH 2/4] ASoC: wm8998: Fix event generation for input mux

[Charles Keepax <ckeepax@opensource.cirrus.com>]

wm8998_inmux_put returns the value of snd_soc_dapm_mux_update_power,
which returns a 1 if a path was found for the kcontrol. This is
obviously different to the expected return a 1 if the control
was updated value. This results in spurious notifications to
user-space. Update the handling to only return a 1 when the value is
changed.

Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
---
 sound/soc/codecs/wm8998.c | 21 ++++++++++++++-------
 1 file changed, 14 insertions(+), 7 deletions(-)

diff --git a/sound/soc/codecs/wm8998.c b/sound/soc/codecs/wm8998.c
index 00b59fc9b1fe0..ab5481187c710 100644
--- a/sound/soc/codecs/wm8998.c
+++ b/sound/soc/codecs/wm8998.c
@@ -108,6 +108,7 @@ static int wm8998_inmux_put(struct snd_kcontrol *kcontrol,
 	struct soc_enum *e = (struct soc_enum *)kcontrol->private_value;
 	unsigned int mode_reg, mode_index;
 	unsigned int mux, inmode, src_val, mode_val;
+	int change, ret;
 
 	mux = ucontrol->value.enumerated.item[0];
 	if (mux > 1)
@@ -137,14 +138,20 @@ static int wm8998_inmux_put(struct snd_kcontrol *kcontrol,
 	snd_soc_component_update_bits(component, mode_reg,
 				      ARIZONA_IN1_MODE_MASK, mode_val);
 
-	snd_soc_component_update_bits(component, e->reg,
-				      ARIZONA_IN1L_SRC_MASK |
-				      ARIZONA_IN1L_SRC_SE_MASK,
-				      src_val);
+	change = snd_soc_component_update_bits(component, e->reg,
+					       ARIZONA_IN1L_SRC_MASK |
+					       ARIZONA_IN1L_SRC_SE_MASK,
+					       src_val);
 
-	return snd_soc_dapm_mux_update_power(dapm, kcontrol,
-					     ucontrol->value.enumerated.item[0],
-					     e, NULL);
+	ret = snd_soc_dapm_mux_update_power(dapm, kcontrol,
+					    ucontrol->value.enumerated.item[0],
+					    e, NULL);
+	if (ret < 0) {
+		dev_err(arizona->dev, "Failed to update demux power state: %d\n", ret);
+		return ret;
+	}
+
+	return change;
 }
 
 static const char * const wm8998_inmux_texts[] = {
-- 
2.30.2