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From:   Frank Lee <tiny.windzz@gmail.com>
Date:   Fri, 6 Nov 2020 21:41:05 +0800
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Subject: Re: [PATCH v1 17/30] mmc: sdhci-tegra: Support OPP and core voltage scaling
To:     Dmitry Osipenko <digetx@gmail.com>
Cc:     Viresh Kumar <viresh.kumar@linaro.org>,
        Thierry Reding <thierry.reding@gmail.com>,
        Jonathan Hunter <jonathanh@nvidia.com>,
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On Fri, Nov 6, 2020 at 9:18 PM Dmitry Osipenko <digetx@gmail.com> wrote:
>
> 06.11.2020 09:15, Viresh Kumar =D0=BF=D0=B8=D1=88=D0=B5=D1=82:
> > Setting regulators for count as 0 doesn't sound good to me.
> >
> > But, I understand that you don't want to have that if (have_regulator)
> > check, and it is a fair request. What I will instead do is, allow all
> > dev_pm_opp_put*() API to start accepting a NULL pointer for the OPP
> > table and fail silently. And so you won't be required to have this
> > unwanted check. But you will be required to save the pointer returned
> > back by dev_pm_opp_set_regulators(), which is the right thing to do
> > anyways.
>
> Perhaps even a better variant could be to add a devm versions of the OPP
> API functions, then drivers won't need to care about storing the
> opp_table pointer if it's unused by drivers.

I think so. The consumer may not be so concerned about the status of
these OPP tables.
If the driver needs to manage the release, it needs to add a pointer
to their driver global structure.

Maybe it's worth having these devm interfaces for opp.

Yangtao