[PATCH] ASoC: fsl_esai: Add freq check in set_dai_sysclk()

[Nicolin Chen <nicoleotsuka@gmail.com>]

The freq parameter indicates the physical frequency of an actual
input clock or a desired frequency of an output clock for HCKT/R.
It should never be passed 0. This might cause Division-by-zero.

So this patch adds a check to fix it.

Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
---
 sound/soc/fsl/fsl_esai.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/sound/soc/fsl/fsl_esai.c b/sound/soc/fsl/fsl_esai.c
index da8fd98..d79e99e 100644
--- a/sound/soc/fsl/fsl_esai.c
+++ b/sound/soc/fsl/fsl_esai.c
@@ -226,6 +226,12 @@ static int fsl_esai_set_dai_sysclk(struct snd_soc_dai *dai, int clk_id,
 	unsigned long clk_rate;
 	int ret;
 
+	if (freq == 0) {
+		dev_err(dai->dev, "%sput freq of HCK%c should not be 0Hz\n",
+			in ? "in" : "out", tx ? 'T' : 'R');
+		return -EINVAL;
+	}
+
 	/* Bypass divider settings if the requirement doesn't change */
 	if (freq == esai_priv->hck_rate[tx] && dir == esai_priv->hck_dir[tx])
 		return 0;
-- 
2.7.4