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Date:   Fri, 8 Feb 2019 11:00:53 +0000
From:   Sudeep Holla <sudeep.holla@arm.com>
To:     Marek Szyprowski <m.szyprowski@samsung.com>
Cc:     linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org,
        linux-samsung-soc@vger.kernel.org,
        Viresh Kumar <viresh.kumar@linaro.org>,
        "Rafael J . Wysocki" <rjw@rjwysocki.net>,
        Nishanth Menon <nm@ti.com>, Stephen Boyd <sboyd@kernel.org>,
        Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>,
        Dave Gerlach <d-gerlach@ti.com>,
        Wolfram Sang <wsa@the-dreams.de>
Subject: Re: [PATCH 0/2] cpufreq/opp: rework regulator initialization
Message-ID: <20190208110053.GA7913@e107155-lin>
References: <CGME20190207122255eucas1p1cdebed838c799eca46cce6a654a26187@eucas1p1.samsung.com>
 <20190207122227.19873-1-m.szyprowski@samsung.com>
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On Thu, Feb 07, 2019 at 01:22:25PM +0100, Marek Szyprowski wrote:
> Dear All,
>
> This is a scenario that triggers the above issue:
>

[...]

> 1. system disables non-boot cpu's at the end of system suspend procedure,
> 2. this in turn deinitializes cpufreq drivers for the disabled cpus,
> 3. early in the system resume procedure all cpus are got back to online
>    state,
> 4. this in turn causes cpufreq to be initialized for the newly onlined
>    cpus,
> 5. cpufreq-dt acquires all its resources (clocks, regulators) during
>    ->init() callback,

This is strictly not just restricted to cpufreq-dt, but to any driver
supporting multiple policies. So we need a generic fix not just
cpufreq-dt specific.

--
Regards,
Sudeep