[PATCH 1/1] PWM-atmel: Fixed a bug which set the pwm clock prescaler incorrectly. In the defect code the prescaler was always one more than expected value, which resulted in the pwm output with wrong frequency and duty cycle.

From: hachyang
Date: Wed Sep 10 2014 - 17:36:42 EST


From: ryang <ryang@xxxxxxxx>

Signed-off-by: ryang <ryang@xxxxxxxx>
---
drivers/pwm/pwm-atmel.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/pwm/pwm-atmel.c b/drivers/pwm/pwm-atmel.c
index 6e700a5..2dca0bf 100644
--- a/drivers/pwm/pwm-atmel.c
+++ b/drivers/pwm/pwm-atmel.c
@@ -128,7 +128,8 @@ static int atmel_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
return -EINVAL;
}
}
-
+ /* Need to reduce the prescaler by 1 */
+ pres--;
/* Calculate the duty cycles */
prd = div;
div *= duty_ns;
--
1.9.1

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