Re: [PATCH v4 2/4] OPP: change parameter to device pointer in dev_pm_opp_of_register_em()

[Lukasz Luba]

On 3/13/20 10:15 AM, Quentin Perret wrote:
> On Monday 09 Mar 2020 at 13:41:15 (+0000), Lukasz Luba wrote:
> > diff --git a/drivers/cpufreq/cpufreq-dt.c b/drivers/cpufreq/cpufreq-dt.c
> > index d2b5f062a07b..676b56424886 100644
> > --- a/drivers/cpufreq/cpufreq-dt.c
> > +++ b/drivers/cpufreq/cpufreq-dt.c
> > @@ -275,7 +275,9 @@ static int cpufreq_init(struct cpufreq_policy *policy)
> >   	policy->cpuinfo.transition_latency = transition_latency;
> >   	policy->dvfs_possible_from_any_cpu = true;
> >   
> > -	dev_pm_opp_of_register_em(policy->cpus);
> > +	ret = dev_pm_opp_of_register_em(cpu_dev, policy->cpus);
> > +	if (ret)
> > +		dev_dbg(cpu_dev, "Couldn't register Energy Model %d\n", ret);
> >   
> >   	return 0;
>
> Ah, that answers my comment on patch 01. You're adding the error
> messages here.
>
> Isn't this more boilerplate for the drivers ? All they do is print the
> same debug message. Maybe just move it inside dev_pm_opp_of_register_em
> directly ?

Agree. I could add a 'fail' label in dev_pm_opp_of_register_em
something like:

--------------------------------->8----------------
dev_pm_opp_of_register_em
...
	nr_opp = dev_pm_opp_get_opp_count(dev);
	if (nr_opp <= 0) {
		ret = -EINVAL;
		goto fail;
	}

...
	ret = em_register_perf_domain()
	if (ret)
		goto fail;

	return 0;

fail:
	dev_dbg(cpu_dev, "Couldn't register Energy Model %d\n", ret);
	return ret
------------------------8<-----------------

Makes more sense, agree, thank you for your suggestion.

I will remove this
  if (ret)
	dev_dbg(cpu_dev, "Couldn't register Energy Model %d\n", ret);
from the cpufreq drivers.


Regards,
Lukasz