[PATCH -next] greybus/audio_helper: Add missing unlock to avoid mismatched lock

[Zheng Yongjun]

Fix a missing unlock in the error branch.

Signed-off-by: Zheng Yongjun <zhengyongjun3@xxxxxxxxxx>
---
 drivers/staging/greybus/audio_helper.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/staging/greybus/audio_helper.c b/drivers/staging/greybus/audio_helper.c
index 237531ba60f3..293675dbea10 100644
--- a/drivers/staging/greybus/audio_helper.c
+++ b/drivers/staging/greybus/audio_helper.c
@@ -135,6 +135,7 @@ int gbaudio_dapm_free_controls(struct snd_soc_dapm_context *dapm,
 		if (!w) {
 			dev_err(dapm->dev, "%s: widget not found\n",
 				widget->name);
+			mutex_unlock(&dapm->card->dapm_mutex);
 			return -EINVAL;
 		}
 		widget++;
-- 
2.22.0