diff options
| author |   Stefan Wahren <stefan.wahren@i2se.com> | 2015-12-01 22:55:40 +0000 |
|---|---|---|
| committer |   Thierry Reding <thierry.reding@gmail.com> | 2015-12-16 16:45:10 +0100 |
| commit | fd13c14426299e75983a0cd3edf53dfa4083a70a (patch) | |
| tree | 1698122b905b9bfbaa364b11dc38ad9ac435674b /drivers/pwm | |
| parent | pwm: bcm2835: Calculate scaler in ->config() (diff) | |
| download | linux-dev-fd13c14426299e75983a0cd3edf53dfa4083a70a.tar.xz linux-dev-fd13c14426299e75983a0cd3edf53dfa4083a70a.zip | |
pwm: bcm2835: Prevent division by zero
It's possible that the PWM clock becomes an orphan. So better check the
result of clk_get_rate() in order to prevent a division by zero.
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Diffstat (limited to 'drivers/pwm')
| -rw-r--r-- | drivers/pwm/pwm-bcm2835.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/drivers/pwm/pwm-bcm2835.c b/drivers/pwm/pwm-bcm2835.c index 174cca92f690..31a6992a445c 100644 --- a/drivers/pwm/pwm-bcm2835.c +++ b/drivers/pwm/pwm-bcm2835.c @@ -65,7 +65,15 @@ static int bcm2835_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, int duty_ns, int period_ns) { struct bcm2835_pwm *pc = to_bcm2835_pwm(chip); - unsigned long scaler = NSEC_PER_SEC / clk_get_rate(pc->clk); + unsigned long rate = clk_get_rate(pc->clk); + unsigned long scaler; + + if (!rate) { + dev_err(pc->dev, "failed to get clock rate\n"); + return -EINVAL; + } + + scaler = NSEC_PER_SEC / rate; if (period_ns <= MIN_PERIOD) { dev_err(pc->dev, "period %d not supported, minimum %d\n", |