[PATCH v2] pwm: pwm-lpc18xx-sct: test clock rate to avoid division by 0

From: Wolfram Sang
Date: Wed Mar 02 2016 - 17:59:36 EST


From: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>

The clk API may return 0 on clk_get_rate, so we should check the result before
using it as a divisor.

Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
---
drivers/pwm/pwm-lpc18xx-sct.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/pwm/pwm-lpc18xx-sct.c b/drivers/pwm/pwm-lpc18xx-sct.c
index 9163085101bc94..9861fed4e67d04 100644
--- a/drivers/pwm/pwm-lpc18xx-sct.c
+++ b/drivers/pwm/pwm-lpc18xx-sct.c
@@ -360,6 +360,11 @@ static int lpc18xx_pwm_probe(struct platform_device *pdev)
}

lpc18xx_pwm->clk_rate = clk_get_rate(lpc18xx_pwm->pwm_clk);
+ if (!lpc18xx_pwm->clk_rate) {
+ dev_err(&pdev->dev, "pwm clock has no frequency\n");
+ ret = -EINVAL;
+ goto disable_pwmclk;
+ }

mutex_init(&lpc18xx_pwm->res_lock);
mutex_init(&lpc18xx_pwm->period_lock);
--
2.7.0