37 lines
1.3 KiB
Diff
37 lines
1.3 KiB
Diff
From: Stefan Wahren <stefan.wahren@i2se.com>
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Date: Tue, 1 Dec 2015 22:55:40 +0000
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Subject: [2/3] pwm: bcm2835: Prevent division by zero
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Origin: https://git.kernel.org/cgit/linux/kernel/git/thierry.reding/linux-pwm.git/commit?id=fd13c14426299e75983a0cd3edf53dfa4083a70a
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It's possible that the PWM clock becomes an orphan. So better check the
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result of clk_get_rate() in order to prevent a division by zero.
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Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
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Reviewed-by: Eric Anholt <eric@anholt.net>
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Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
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---
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drivers/pwm/pwm-bcm2835.c | 10 +++++++++-
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1 file changed, 9 insertions(+), 1 deletion(-)
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diff --git a/drivers/pwm/pwm-bcm2835.c b/drivers/pwm/pwm-bcm2835.c
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index 174cca9..31a6992 100644
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--- a/drivers/pwm/pwm-bcm2835.c
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+++ b/drivers/pwm/pwm-bcm2835.c
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@@ -65,7 +65,15 @@ static int bcm2835_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
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int duty_ns, int period_ns)
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{
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struct bcm2835_pwm *pc = to_bcm2835_pwm(chip);
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- unsigned long scaler = NSEC_PER_SEC / clk_get_rate(pc->clk);
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+ unsigned long rate = clk_get_rate(pc->clk);
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+ unsigned long scaler;
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+
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+ if (!rate) {
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+ dev_err(pc->dev, "failed to get clock rate\n");
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+ return -EINVAL;
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+ }
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+
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+ scaler = NSEC_PER_SEC / rate;
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if (period_ns <= MIN_PERIOD) {
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dev_err(pc->dev, "period %d not supported, minimum %d\n",
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