Re: [PATCH 11/13] devfreq: tegra30: Migrate to dev_pm_opp_set_opp()

From: Viresh Kumar
Date: Fri Jan 22 2021 - 01:29:17 EST


On 22-01-21, 00:36, Dmitry Osipenko wrote:
> 21.01.2021 14:17, Viresh Kumar пишет:
> > dev_pm_opp_set_bw() is getting removed and dev_pm_opp_set_opp() should
> > be used instead. Migrate to the new API.
> >
> > Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
> > ---
> > drivers/devfreq/tegra30-devfreq.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/devfreq/tegra30-devfreq.c b/drivers/devfreq/tegra30-devfreq.c
> > index 117cad7968ab..d2477d7d1f66 100644
> > --- a/drivers/devfreq/tegra30-devfreq.c
> > +++ b/drivers/devfreq/tegra30-devfreq.c
> > @@ -647,7 +647,7 @@ static int tegra_devfreq_target(struct device *dev, unsigned long *freq,
> > return PTR_ERR(opp);
> > }
> >
> > - ret = dev_pm_opp_set_bw(dev, opp);
> > + ret = dev_pm_opp_set_opp(dev, opp);
> > dev_pm_opp_put(opp);
> >
> > return ret;
> >
>
> This patch introduces a very serious change that needs to be fixed.
>
> Now dev_pm_opp_set_opp() changes both clock rate and bandwidth, this is
> unacceptable for this driver because it shall not touch the clock rate.
>
> I think dev_pm_opp_set_bw() can't be removed.

I am wondering here on what would be a better solution, do what you
said or introduce another helper like dev_pm_opp_clear_clk(), which
will make sure the OPP core doesn't play with device's clk.

--
viresh