[PATCH 3/4] ASoC: cs47l92: Fix event generation for OUT1 demux

[Charles Keepax]

cs47l92_put_demux 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 at opensource.cirrus.com>
---
 sound/soc/codecs/cs47l92.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/sound/soc/codecs/cs47l92.c b/sound/soc/codecs/cs47l92.c
index a1b8dcdb9f7b7..444026b7d54b3 100644
--- a/sound/soc/codecs/cs47l92.c
+++ b/sound/soc/codecs/cs47l92.c
@@ -119,7 +119,13 @@ static int cs47l92_put_demux(struct snd_kcontrol *kcontrol,
 end:
 	snd_soc_dapm_mutex_unlock(dapm);
 
-	return snd_soc_dapm_mux_update_power(dapm, kcontrol, mux, e, NULL);
+	ret = snd_soc_dapm_mux_update_power(dapm, kcontrol, mux, e, NULL);
+	if (ret < 0) {
+		dev_err(madera->dev, "Failed to update demux power state: %d\n", ret);
+		return ret;
+	}
+
+	return change;
 }
 
 static SOC_ENUM_SINGLE_DECL(cs47l92_outdemux_enum,
-- 
2.30.2