[PATCH v2 09/10] ASoC: fsl_sai: Reject bclk ratio smaller than slot width

[phucduc.bui@gmail.com]

From: bui duc phuc <phucduc.bui@gmail.com>

In hw_params(), when a bclk ratio is set, the number of slots is
computed as bclk_ratio / slot_width. If the ratio is smaller than
the slot width, slots becomes zero and the following
DIV_ROUND_UP(channels, slots) divides by zero.

Return -EINVAL in this case.

Signed-off-by: bui duc phuc <phucduc.bui@gmail.com>
---
 sound/soc/fsl/fsl_sai.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/sound/soc/fsl/fsl_sai.c b/sound/soc/fsl/fsl_sai.c
index 5c50ed7c2258..c61703ddb6f8 100644
--- a/sound/soc/fsl/fsl_sai.c
+++ b/sound/soc/fsl/fsl_sai.c
@@ -632,8 +632,14 @@ static int fsl_sai_hw_params(struct snd_pcm_substream *substream,
 
 	if (sai->slots[tx])
 		slots = sai->slots[tx];
-	else if (sai->bclk_ratio)
+	else if (sai->bclk_ratio) {
+		if (sai->bclk_ratio < slot_width) {
+			dev_err(cpu_dai->dev, "bclk ratio %u < slot width %u\n",
+				sai->bclk_ratio, slot_width);
+			return -EINVAL;
+		}
 		slots = sai->bclk_ratio / slot_width;
+	}
 
 	pins = DIV_ROUND_UP(channels, slots);
 
-- 
2.43.0