ASoC: fsl_easrc: Fix event generation in fsl_easrc_iec958_put_bits()

ALSA controls should return 1 if the value in the control changed but the
control put operation fsl_easrc_iec958_put_bits() unconditionally returns
0, causing ALSA to not generate any change events. This is detected by
mixer-test with large numbers of messages in the form:

    No event generated for Context 3 IEC958 CS5
    Context 3 IEC958 CS5.0 orig 5224 read 5225, is_volatile 0

Add a suitable check.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://patch.msgid.link/20260205-asoc-fsl-easrc-fix-events-v1-1-39d4c766918b@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/fsl/fsl_easrc.c b/sound/soc/fsl/fsl_easrc.c
index e64a0d97afd0cb5caaff33fb101e4bf28f34ae4f..5b6204923e8ab9cf6dd7fbc93e8b6773e80bc015 100644 (file)
--- a/sound/soc/fsl/fsl_easrc.c
+++ b/sound/soc/fsl/fsl_easrc.c
@@ -52,10 +52,13 @@ static int fsl_easrc_iec958_put_bits(struct snd_kcontrol *kcontrol,
        struct soc_mreg_control *mc =
                (struct soc_mreg_control *)kcontrol->private_value;
        unsigned int regval = ucontrol->value.integer.value[0];
+       int ret;
+
+       ret = (easrc_priv->bps_iec958[mc->regbase] != regval);
 
        easrc_priv->bps_iec958[mc->regbase] = regval;
 
-       return 0;
+       return ret;
 }
 
 static int fsl_easrc_iec958_get_bits(struct snd_kcontrol *kcontrol,