[PATCH v2] i2c: efm32: Prevent potential division by zero

[Axel Lin <axel.lin@ingics.com>]

Make sure we don't OOPS in case clock-frequency is set to 0 in a DT. The
variable set here is later used as a divisor.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
---
Hi Uwe,
If my understand is correct, you prefer to make it return error rather
than using default frequency setting if DT setting is wrong.

v2: Make probe return error instead of using default frequency.

 drivers/i2c/busses/i2c-efm32.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/i2c/busses/i2c-efm32.c b/drivers/i2c/busses/i2c-efm32.c
index 8eff627..7c0636e 100644
--- a/drivers/i2c/busses/i2c-efm32.c
+++ b/drivers/i2c/busses/i2c-efm32.c
@@ -395,6 +395,13 @@ static int efm32_i2c_probe(struct platform_device *pdev)
 		frequency = 100000;
 		dev_info(&pdev->dev, "defaulting to 100 kHz\n");
 	}
+
+	if (frequency == 0) {
+		dev_err(&pdev->dev, "Invalid clock-frequency\n");
+		ret = -EINVAL;
+		goto err_disable_clk;
+	}
+
 	ddata->frequency = frequency;
 
 	rate = clk_get_rate(ddata->clk);
-- 
2.5.0