ASoC: codecs: lpass-wsa-macro: handle unexpected input

Static analysis reports this problem

lpass-wsa-macro.c:1732:6: warning: Array subscript is undefined
        if (wsa->ec_hq[ec_tx]) {
            ^~~~~~~~~~~~~~~~~

The happens because 'ec_tx' is never initialized and there is
no default in switch statement that sets ec_tx.  Add a default
case that returns an error before the array is accessed.

Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20210430142117.3272772-1-trix@redhat.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/codecs/lpass-wsa-macro.c b/sound/soc/codecs/lpass-wsa-macro.c
index 1a7fa54..d3ac318 100644 (file)
--- a/sound/soc/codecs/lpass-wsa-macro.c
+++ b/sound/soc/codecs/lpass-wsa-macro.c
@@ -1727,6 +1727,10 @@ static int wsa_macro_enable_echo(struct snd_soc_dapm_widget *w,
                val = val & CDC_WSA_RX_MIX_TX1_SEL_MASK;
                ec_tx = (val >> CDC_WSA_RX_MIX_TX1_SEL_SHFT) - 1;
                break;
+       default:
+               dev_err(component->dev, "%s: Invalid shift %u\n",
+                       __func__, w->shift);
+               return -EINVAL;
        }
 
        if (wsa->ec_hq[ec_tx]) {