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Date:   Wed, 16 Feb 2022 01:00:33 +0300
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Subject: Re: [PATCH v6 00/21] Introduce power-off+restart call chain API
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From:   Dmitry Osipenko <digetx@gmail.com>
Cc:     linux-kernel@vger.kernel.org, linux-csky@vger.kernel.org,
        linux-ia64@vger.kernel.org, linux-m68k@lists.linux-m68k.org,
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        Thierry Reding <thierry.reding@gmail.com>,
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        Russell King <linux@armlinux.org.uk>,
        Catalin Marinas <catalin.marinas@arm.com>,
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        Mark Brown <broonie@kernel.org>, Pavel Machek <pavel@ucw.cz>,
        Lee Jones <lee.jones@linaro.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Guenter Roeck <linux@roeck-us.net>,
        Daniel Lezcano <daniel.lezcano@linaro.org>,
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References: <20220130233718.21544-1-digetx@gmail.com>
To:     "Rafael J. Wysocki" <rafael@kernel.org>
In-Reply-To: <20220130233718.21544-1-digetx@gmail.com>
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31.01.2022 02:36, Dmitry Osipenko пишет:
> Problem
> -------
> 
> SoC devices require power-off call chaining functionality from kernel.
> We have a widely used restart chaining provided by restart notifier API,
> but nothing for power-off.
> 
> Solution
> --------
> 
> Introduce new API that provides both restart and power-off call chains.
> 
> Why combine restart with power-off? Because drivers often do both.
> More practical to have API that provides both under the same roof.
> 
> The new API is designed with simplicity and extensibility in mind.
> It's built upon the existing restart and reboot APIs. The simplicity
> is in new helper functions that are convenient for drivers. The
> extensibility is in the design that doesn't hardcode callback
> arguments, making easy to add new parameters and remove old.
> 
> This is a third attempt to introduce the new API. First was made by
> Guenter Roeck back in 2014, second was made by Thierry Reding in 2017.
> In fact the work didn't stop and recently arm_pm_restart() was removed
> from v5.14 kernel, which was a part of preparatory work started by
> Guenter Roeck. I took into account experience and ideas from the
> previous attempts, extended and polished them.


Rafael and all, do you see anything critical that needs to be improved
in this v6?

Will be great if you could take this patchset via the power tree if it
looks okay, or give an ack.