Hello Paul, On Sat, Jan 05, 2019 at 05:46:18PM -0300, Paul Cercueil wrote: > On Sat, Jan 5, 2019 at 4:42 PM, Uwe Kleine-König > <u.kleine-koenig@xxxxxxxxxxxxxx> wrote: > > On Thu, Dec 27, 2018 at 07:13:04PM +0100, Paul Cercueil wrote: > > > The ingenic-timer "TCU" driver provides us with a regmap, that we > > > can > > > use to safely access the TCU registers. > > > > > > While this driver is devicetree-compatible, it is never (as of now) > > > probed from devicetree, so this change does not introduce a ABI > > > problem > > > with current devicetree files. > > > > Does it change behaviour? If so, how? > > No, it does not change the behaviour. Then this paragraph in the commit log can better be dropped. > > > @@ -113,26 +117,37 @@ static int jz4740_pwm_apply(struct pwm_chip > > > *chip, struct pwm_device *pwm, > > > > > > jz4740_pwm_disable(chip, pwm); > > > > > > - jz4740_timer_set_count(pwm->hwpwm, 0); > > > - jz4740_timer_set_duty(pwm->hwpwm, duty); > > > - jz4740_timer_set_period(pwm->hwpwm, period); > > > + /* Set abrupt shutdown */ > > > + regmap_update_bits(jz4740->map, TCU_REG_TCSRc(pwm->hwpwm), > > > + TCU_TCSR_PWM_SD, TCU_TCSR_PWM_SD); > > > > I think I already pointed that out before: abrupt mode is wrong. If > > .apply is called with a new set of parameters the currently running > > period with the old values is expected to complete before the new values > > take effect. > > You pointed it, indeed; but I won't change it until I can verify that the > behaviour is correct (which does not seem to be the case even if I leave > this bit cleared). Besides, this is the TCU patchset, fixes and patches > unrelated to the TCU don't belong here. So abrupt mode was already used before? Then maybe note in a comment that this is wrong but kept for now as this change is only refactoring without changing behaviour. Best regards Uwe -- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | http://www.pengutronix.de/ |