ASoC: rt274: Variable "buf" in function rt274_jack_detect() could be uninitialized

In function rt274_jack_detect(), local variable "buf" could
be uninitialized if function regmap_read() returns -EINVAL.
However, it will be used to calculate "hp" and "mic" and
make their value unpredictable while those value are used
in the caller. This is potentially unsafe.
Signed-off-by: Yizhuo <yzhai003@ucr.edu>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/rt274.c

@@ -353,6 +353,7 @@ static void rt274_index_sync(struct snd_soc_component *component)
 static int rt274_jack_detect(struct rt274_priv *rt274, bool *hp, bool *mic)
 {
 	unsigned int buf;
+	int ret;
 
 	*hp = false;
 	*mic = false;
@@ -360,9 +361,15 @@ static int rt274_jack_detect(struct rt274_priv *rt274, bool *hp, bool *mic)
 	if (!rt274->component)
 		return -EINVAL;
 
-	regmap_read(rt274->regmap, RT274_GET_HP_SENSE, &buf);
+	ret = regmap_read(rt274->regmap, RT274_GET_HP_SENSE, &buf);
+	if (ret)
+		return ret;
+
 	*hp = buf & 0x80000000;
-	regmap_read(rt274->regmap, RT274_GET_MIC_SENSE, &buf);
+	ret = regmap_read(rt274->regmap, RT274_GET_MIC_SENSE, &buf);
+	if (ret)
+		return ret;
+
 	*mic = buf & 0x80000000;
 
 	pr_debug("*hp = %d *mic = %d\n", *hp, *mic);