Problem with s3c24xx pwm driver

Eric Miao eric.y.miao at
Wed Sep 23 15:03:17 EDT 2009

On Wed, Sep 23, 2009 at 11:24 PM, Vasily Khoruzhick <anarsoul at> wrote:
> Hi,
> I'm encountering very strange problem with s3c24xx pwm driver. I'm using it
> with pwm-bl driver. When backlight level is 0, pwm-bl calls pwm_config(0,
> period); pwm_disable(), otherwise it calls pwm_config(duty, period);
> pwm_enable().
> Problem is that after pwm was disabled, it can't be enabled with
> pwm_config(duty, period); pwm_enable() for some (but not all) _valid_
> duty/period combinations.
> pwm-bl works fine if pwm_disable() call is commented out.
> Does anybody know how to solve this problem? Any suggestions?

Sounds like there are cases where the pwm_enable() and pwm_disable()
are not paired? You may want to print out the reference count each time
to see if this is true.

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