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To:     Srinath Mannam <srinath.mannam@broadcom.com>,
        Sudeep Holla <sudeep.holla@arm.com>
From:   Stephen Boyd <sboyd@kernel.org>
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        Sudeep Holla <sudeep.holla@arm.com>,
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Subject: Re: ACPI support in common clock framework
Date:   Mon, 25 Jun 2018 16:37:16 -0700
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Quoting Sudeep Holla (2018-06-25 10:15:45)
> =

> =

> On 25/06/18 17:37, Stephen Boyd wrote:
> > Quoting Rafael J. Wysocki (2018-06-16 08:50:18)
> >> On Fri, Jun 15, 2018 at 7:43 PM, Stephen Boyd <sboyd@kernel.org> wrote:
> >>>
> >>> Is this for clk_enable/disable? What about clk_set_rate() or
> >>> clk_set_phase()? Is ACPI's AML taking care of that?
> >>
> >> That's for clk_enable/disable AFAICS.
> >>
> >> AML doesn't manage device performance states at all.
> > =

> > Alright. We may need to add a better way for device drivers to get
> > handles to clk pointers on ACPI firmware so they can change frequencies
> > or phase, etc. =

> =

> Is there any specific usecase/device needing this in the kernel ? SPI
> slaves ?

Mark Brown has been pushing x86 folks to use clk framework for audio
drivers in ASoC. I haven't seen other uses besides that really.