[PATCH 4.9 24/33] ASoC: ops: Fix stereo change notifications in snd_soc_put_volsw()

[Greg Kroah-Hartman]

From: Mark Brown <broonie@xxxxxxxxxx>

commit 564778d7b1ea465f9487eedeece7527a033549c5 upstream.

When writing out a stereo control we discard the change notification from
the first channel, meaning that events are only generated based on changes
to the second channel. Ensure that we report a change if either channel
has changed.

Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/20220201155629.120510-2-broonie@xxxxxxxxxx
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 sound/soc/soc-ops.c |   14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

--- a/sound/soc/soc-ops.c
+++ b/sound/soc/soc-ops.c
@@ -319,7 +319,7 @@ int snd_soc_put_volsw(struct snd_kcontro
 	unsigned int sign_bit = mc->sign_bit;
 	unsigned int mask = (1 << fls(max)) - 1;
 	unsigned int invert = mc->invert;
-	int err;
+	int err, ret;
 	bool type_2r = false;
 	unsigned int val2 = 0;
 	unsigned int val, val_mask;
@@ -361,12 +361,18 @@ int snd_soc_put_volsw(struct snd_kcontro
 	err = snd_soc_component_update_bits(component, reg, val_mask, val);
 	if (err < 0)
 		return err;
+	ret = err;
 
-	if (type_2r)
+	if (type_2r) {
 		err = snd_soc_component_update_bits(component, reg2, val_mask,
-			val2);
+						    val2);
+		/* Don't discard any error code or drop change flag */
+		if (ret == 0 || err < 0) {
+			ret = err;
+		}
+	}
 
-	return err;
+	return ret;
 }
 EXPORT_SYMBOL_GPL(snd_soc_put_volsw);