On Mon, Apr 1, 2013 at 3:32 PM, Axel Lin <[email protected]> wrote: > 2013/4/1 Eric Miao <[email protected]>: >> On Sun, Mar 31, 2013 at 11:04 PM, Axel Lin <[email protected]> wrote: >>> clk_enable/clk_disable maintain an enable_count, clk_prepare and >>> clk_unprepare >>> also maintain a prepare_count. These APIs will do prepare/enable when the >>> first >>> user calling these APIs, and do disable/unprepare when the corresponding >>> counter >>> reach 0. Thus We don't need to maintain a clk_enabled counter here. >> >> The original intention is to keep a paired clk enable counter no matter >> how the user calls pwm_enable()/pwm_disable() in pair or not, if that's >> no longer the case. > > We don't need to worry that case: > In pwm core, both pwm_enable() and pwm_disable() will always check > PWMF_ENABLED flag.
That's good then, this part of the code was dated before the pwm core, looks like this has been carefully handled. Have my ack on this one then: Acked-by: Eric Miao <[email protected]> > > > /** > * pwm_enable() - start a PWM output toggling > * @pwm: PWM device > */ > int pwm_enable(struct pwm_device *pwm) > { > if (pwm && !test_and_set_bit(PWMF_ENABLED, &pwm->flags)) > return pwm->chip->ops->enable(pwm->chip, pwm); > > return pwm ? 0 : -EINVAL; > } > EXPORT_SYMBOL_GPL(pwm_enable); > > /** > * pwm_disable() - stop a PWM output toggling > * @pwm: PWM device > */ > void pwm_disable(struct pwm_device *pwm) > { > if (pwm && test_and_clear_bit(PWMF_ENABLED, &pwm->flags)) > pwm->chip->ops->disable(pwm->chip, pwm); > } > EXPORT_SYMBOL_GPL(pwm_disable); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
