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Subject: RE: Re: devfreq relation with pm qos
Reply-To: myungjoo.ham@samsung.com
From:   MyungJoo Ham <myungjoo.ham@samsung.com>
To:     noman pouigt <variksla@gmail.com>,
        "linux-pm@vger.kernel.org" <linux-pm@vger.kernel.org>,
        Kyungmin Park <kyungmin.park@samsung.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
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Message-ID: <20180710055847epcms1p2eed3f89ae0220a06051faa83cc8b21ed@epcms1p2>
Date:   Tue, 10 Jul 2018 14:58:47 +0900
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> + dev freq maintainters.
> 
> On Mon, Jul 9, 2018 at 3:37 AM, noman pouigt <variksla@gmail.com> wrote:
> > folks,
> >
> > I am trying to figure out the relationship between PM QOS
> > with devfreq framework. I see this thread[1] where MyungJoo
> > talks about QOS and devfreq but that control is through
> > sysfs but I don't see any relation of pm qos (kernel/power/qos.c)
> > with devfreq directly as devfreq is not calling any of the QOS
> > api's. Is this intended?
> >
> > Isn't QOS value update using pm_qos_update_request has a
> > direct relation with devfreq drivers i.e. setting the value to
> > high or low selects the corresponding voltage and frequency
> > setting in devfreq framework? I went through the devfreq
> > drivers and couldn't find that relationship. Is this by design or
> > I am missing something very obvious?
> >
> > [1] https://lwn.net/Articles/484161/

Hello,

Unfortunately, the suggested concept in the referred article was not ever
accepted in the mainline.

Cheers,
MyungJo