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From:   noman pouigt <variksla@gmail.com>
Date:   Mon, 9 Jul 2018 14:34:53 -0700
Message-ID: <CAES_P+_GTRcFya=N20+b+U=HOpv9gcpYkfJW_gU_i_2pH2hmMA@mail.gmail.com>
Subject: Re: devfreq relation with pm qos
To:     linux-pm@vger.kernel.org, myungjoo.ham@samsung.com,
        kyungmin.park@samsung.com, linux-kernel@vger.kernel.org
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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/