Messages in this thread | | | Date | Thu, 8 Apr 2021 19:36:37 +0200 | From | Uwe Kleine-König <> | Subject | Re: [PATCH v7 5/8] pwm: core: Support new PWM_STAGGERING_ALLOWED flag |
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On Thu, Apr 08, 2021 at 05:51:36PM +0200, Clemens Gruber wrote: > On Thu, Apr 08, 2021 at 02:50:40PM +0200, Thierry Reding wrote: > > Yes, I think that's basically what this is saying. I think we're perhaps > > getting hung up on the terminology here. PWM_STAGGERING_ALLOWED gives > > the impression that we're dealing with some provider-specific feature, > > whereas what we really want to express is that the PWM doesn't care > > exactly when the active cycle starts and based on that a provider that > > can support it may optimize the EMI behavior. > > > > Maybe we can find a better name for this? Ultimately what this means is > > that the consumer is primarily interested in the power output of the PWM > > rather than the exact shape of the signal. So perhaps something like > > PWM_USAGE_POWER would be more appropriate. > > Yes, although it would then no longer be obvious that this feature leads > to improved EMI behavior, as long as we mention that in the docs, I > think it's a good idea > > Maybe document it as follows? > PWM_USAGE_POWER - Allow the driver to delay the start of the cycle > for EMI improvements, as long as the power output stays the same
I don't like both names, because for someone who is only halfway into PWM stuff it is not understandable. Maybe ALLOW_PHASE_SHIFT? When a consumer is only interested in the power output than
.period = 20 .duty_cycle = 5
would also be an allowed response for the request
.period = 200 .duty_cycle = 50
and this is not what is in the focus here.
Best regards Uwe
-- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | https://www.pengutronix.de/ | [unhandled content-type:application/pgp-signature] | |